/*******************************************************************************
 * Copyright IBM Corp. and others 2000
 *
 * This program and the accompanying materials are made available under
 * the terms of the Eclipse Public License 2.0 which accompanies this
 * distribution and is available at https://www.eclipse.org/legal/epl-2.0/
 * or the Apache License, Version 2.0 which accompanies this distribution and
 * is available at https://www.apache.org/licenses/LICENSE-2.0.
 *
 * This Source Code may also be made available under the following
 * Secondary Licenses when the conditions for such availability set
 * forth in the Eclipse Public License, v. 2.0 are satisfied: GNU
 * General Public License, version 2 with the GNU Classpath
 * Exception [1] and GNU General Public License, version 2 with the
 * OpenJDK Assembly Exception [2].
 *
 * [1] https://www.gnu.org/software/classpath/license.html
 * [2] https://openjdk.org/legal/assembly-exception.html
 *
 * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0 OR GPL-2.0-only WITH OpenJDK-assembly-exception-1.0
 *******************************************************************************/

#include <assert.h>
#include <limits.h>
#include <math.h>
#include <stdint.h>
#include "j9.h"
#include "j9cfg.h"
#include "j9consts.h"
#include "j9port.h"
#include "locknursery.h"
#include "thrdsup.h"
#include "thrtypes.h"
#include "codegen/AheadOfTimeCompile.hpp"
#include "codegen/CodeGenerator.hpp"
#include "codegen/Instruction.hpp"
#include "codegen/Machine.hpp"
#include "codegen/Linkage.hpp"
#include "codegen/Linkage_inlines.hpp"
#include "codegen/LiveRegister.hpp"
#include "codegen/Relocation.hpp"
#include "codegen/Register.hpp"
#include "codegen/RegisterPair.hpp"
#include "codegen/ScratchRegisterManager.hpp"
#include "codegen/Snippet.hpp"
#include "codegen/TreeEvaluator.hpp"
#include "codegen/UnresolvedDataSnippet.hpp"
#include "compile/CompilationTypes.hpp"
#include "compile/ResolvedMethod.hpp"
#include "compile/VirtualGuard.hpp"
#include "control/Recompilation.hpp"
#include "control/RecompilationInfo.hpp"
#include "env/CompilerEnv.hpp"
#include "env/CHTable.hpp"
#include "env/IO.hpp"
#include "env/j9method.h"
#include "env/jittypes.h"
#include "env/PersistentCHTable.hpp"
#include "env/VMJ9.h"
#include "il/Block.hpp"
#include "il/DataTypes.hpp"
#include "il/Node.hpp"
#include "il/Node_inlines.hpp"
#include "il/TreeTop.hpp"
#include "il/TreeTop_inlines.hpp"
#include "infra/SimpleRegex.hpp"
#include "OMR/Bytes.hpp"
#include "x/codegen/AllocPrefetchSnippet.hpp"
#include "x/codegen/CheckFailureSnippet.hpp"
#include "x/codegen/CompareAnalyser.hpp"
#include "x/codegen/ForceRecompilationSnippet.hpp"
#include "x/codegen/FPTreeEvaluator.hpp"
#include "x/codegen/J9X86Instruction.hpp"
#include "x/codegen/MonitorSnippet.hpp"
#include "x/codegen/OutlinedInstructions.hpp"
#include "x/codegen/HelperCallSnippet.hpp"
#include "env/CompilerEnv.hpp"
#include "runtime/J9Runtime.hpp"
#include "codegen/J9WatchedStaticFieldSnippet.hpp"
#include "codegen/X86FPConversionSnippet.hpp"

#ifdef TR_TARGET_64BIT
#include "codegen/AMD64PrivateLinkage.hpp"
#endif
#ifdef TR_TARGET_32BIT
#include "codegen/IA32PrivateLinkage.hpp"
#include "codegen/IA32LinkageUtils.hpp"
#endif

#ifdef LINUX
#include <time.h>

#endif

#define NUM_PICS 3

// Minimum number of words for zero-initialization via REP TR::InstOpCode::STOSD
//
#define MIN_REPSTOSD_WORDS 64
static int32_t minRepstosdWords = 0;

// Maximum number of words per loop iteration for loop zero-initialization.
//
#define MAX_ZERO_INIT_WORDS_PER_ITERATION 4
static int32_t maxZeroInitWordsPerIteration = 0;

static bool getNodeIs64Bit(TR::Node *node, TR::CodeGenerator *cg);
static TR::Register *intOrLongClobberEvaluate(TR::Node *node, bool nodeIs64Bit, TR::CodeGenerator *cg);

static uint32_t logBase2(uintptr_t n)
   {
   // Could use leadingZeroes, except we can't call it from here
   //
   uint32_t result = 8*sizeof(n)-1;
   uintptr_t mask  = ((uintptr_t)1) << result;
   while (mask && !(mask & n))
      {
      mask >>= 1;
      result--;
      }
   return result;
   }

// ----------------------------------------------------------------------------
inline void generateLoadJ9Class(TR::Node* node, TR::Register* j9class, TR::Register* object, TR::CodeGenerator* cg)
   {
   bool needsNULLCHK = false;
   TR::ILOpCodes opValue = node->getOpCodeValue();

   if (node->getOpCode().isReadBar() || node->getOpCode().isWrtBar())
      needsNULLCHK = true;
   else
      {
      switch (opValue)
         {
         case TR::monent:
         case TR::monexit:
            TR_ASSERT_FATAL(TR::Compiler->om.areValueTypesEnabled() || TR::Compiler->om.areValueBasedMonitorChecksEnabled(),
                  "monent and monexit are expected for generateLoadJ9Class only when value type or when value based monitor check is enabled");
         case TR::checkcastAndNULLCHK:
            needsNULLCHK = true;
            break;
         case TR::icall: // TR_checkAssignable
            return; // j9class register already holds j9class
         case TR::checkcast:
         case TR::instanceof:
            break;
         default:
            TR_ASSERT_FATAL(false, "Unexpected opCode for generateLoadJ9Class %s.", node->getOpCode().getName());
            break;
         }
      }

   auto use64BitClasses = cg->comp()->target().is64Bit() && !TR::Compiler->om.generateCompressedObjectHeaders();
   auto instr = generateRegMemInstruction(TR::InstOpCode::LRegMem(use64BitClasses), node, j9class, generateX86MemoryReference(object, TR::Compiler->om.offsetOfObjectVftField(), cg), cg);
   if (needsNULLCHK)
      {
      cg->setImplicitExceptionPoint(instr);
      instr->setNeedsGCMap(0xFF00FFFF);
      if (opValue == TR::checkcastAndNULLCHK)
         instr->setNode(cg->comp()->findNullChkInfo(node));
      }


   auto mask = TR::Compiler->om.maskOfObjectVftField();
   if (~mask != 0)
      {
      generateRegImmInstruction(~mask <= 127 ? TR::InstOpCode::ANDRegImms(use64BitClasses) : TR::InstOpCode::ANDRegImm4(use64BitClasses), node, j9class, mask, cg);
      }
   }

static TR_OutlinedInstructions *generateArrayletReference(
   TR::Node           *node,
   TR::Node           *loadOrStoreOrArrayElementNode,
   TR::Instruction *checkInstruction,
   TR::LabelSymbol     *arrayletRefLabel,
   TR::LabelSymbol     *restartLabel,
   TR::Register       *baseArrayReg,
   TR::Register       *loadOrStoreReg,
   TR::Register       *indexReg,
   int32_t            indexValue,
   TR::Register       *valueReg,
   bool               needsBoundCheck,
   TR::CodeGenerator  *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());

   TR::Register *scratchReg = cg->allocateRegister();

   TR_OutlinedInstructions *arrayletRef = new (cg->trHeapMemory()) TR_OutlinedInstructions(arrayletRefLabel, cg);
   arrayletRef->setRestartLabel(restartLabel);

   if (needsBoundCheck)
      {
      // The current block is required for exception handling and anchoring
      // the GC map.
      //
      arrayletRef->setBlock(cg->getCurrentEvaluationBlock());
      arrayletRef->setCallNode(node);
      }

   cg->getOutlinedInstructionsList().push_front(arrayletRef);

   arrayletRef->swapInstructionListsWithCompilation();

   generateLabelInstruction(NULL, TR::InstOpCode::label, arrayletRefLabel, cg)->setNode(node);

   // TODO: REMOVE THIS!
   //
   // This merely indicates that this OOL sequence should be assigned with the non-linear
   // assigner, and should go away when the non-linear assigner handles all OOL sequences.
   //
   arrayletRefLabel->setNonLinear();

   static char *forceArrayletInt = feGetEnv("TR_forceArrayletInt");
   if (forceArrayletInt)
      {
      generateInstruction(TR::InstOpCode::INT3, node, cg);
      }

   // -----------------------------------------------------------------------------------
   // Track all virtual register use within the arraylet path.  This info will be used
   // to adjust the virtual register use counts within the mainline path for more precise
   // register assignment.
   // -----------------------------------------------------------------------------------

   cg->startRecordingRegisterUsage();

   if (needsBoundCheck)
      {
      // -------------------------------------------------------------------------
      // Check if the base array has a spine.  If not, this is a real AIOB.
      // -------------------------------------------------------------------------

      TR::MemoryReference *arraySizeMR =
         generateX86MemoryReference(baseArrayReg, fej9->getOffsetOfContiguousArraySizeField(), cg);

      generateMemImmInstruction(TR::InstOpCode::CMP4MemImms, node, arraySizeMR, 0, cg);

      TR::LabelSymbol *boundCheckFailureLabel = generateLabelSymbol(cg);

      checkInstruction = generateLabelInstruction(TR::InstOpCode::JNE4, node, boundCheckFailureLabel, cg);

      cg->addSnippet(
         new (cg->trHeapMemory()) TR::X86CheckFailureSnippet(
            cg, node->getSymbolReference(),
            boundCheckFailureLabel,
            checkInstruction,
            false
            ));

      // -------------------------------------------------------------------------
      // The array has a spine.  Do a bound check on its true length.
      // -------------------------------------------------------------------------

      arraySizeMR = generateX86MemoryReference(baseArrayReg, fej9->getOffsetOfDiscontiguousArraySizeField(), cg);

      if (!indexReg)
         {
         TR::InstOpCode::Mnemonic op = (indexValue >= -128 && indexValue <= 127) ? TR::InstOpCode::CMP4MemImms : TR::InstOpCode::CMP4MemImm4;
         generateMemImmInstruction(op, node, arraySizeMR, indexValue, cg);
         }
      else
         {
         generateMemRegInstruction(TR::InstOpCode::CMP4MemReg, node, arraySizeMR, indexReg, cg);
         }

      boundCheckFailureLabel = generateLabelSymbol(cg);
      checkInstruction = generateLabelInstruction(TR::InstOpCode::JBE4, node, boundCheckFailureLabel, cg);

      cg->addSnippet(
         new (cg->trHeapMemory()) TR::X86CheckFailureSnippet(
            cg, node->getSymbolReference(),
            boundCheckFailureLabel,
            checkInstruction,
            false
            ));
      }

   // -------------------------------------------------------------------------
   // Determine if a load needs to be decompressed.
   // -------------------------------------------------------------------------

   bool seenCompressionSequence = false;
   bool loadNeedsDecompression = false;

   if (loadOrStoreOrArrayElementNode->getOpCodeValue() == TR::l2a ||
       (((loadOrStoreOrArrayElementNode->getOpCodeValue() == TR::aload ||
         loadOrStoreOrArrayElementNode->getOpCodeValue() == TR::aRegLoad) &&
        node->isSpineCheckWithArrayElementChild()) &&
       comp->target().is64Bit() && comp->useCompressedPointers()))
      loadNeedsDecompression = true;

   TR::Node *actualLoadOrStoreOrArrayElementNode = loadOrStoreOrArrayElementNode;
   while ((loadNeedsDecompression && actualLoadOrStoreOrArrayElementNode->getOpCode().isConversion()) ||
          actualLoadOrStoreOrArrayElementNode->containsCompressionSequence())
      {
      if (actualLoadOrStoreOrArrayElementNode->containsCompressionSequence())
         seenCompressionSequence = true;

      actualLoadOrStoreOrArrayElementNode = actualLoadOrStoreOrArrayElementNode->getFirstChild();
      }

   // -------------------------------------------------------------------------
   // Do the load, store, or array address calculation
   // -------------------------------------------------------------------------

   TR::DataType dt = actualLoadOrStoreOrArrayElementNode->getDataType();
   int32_t elementSize;

   if (dt == TR::Address)
      {
      elementSize = TR::Compiler->om.sizeofReferenceField();
      }
   else
      {
      elementSize = TR::Symbol::convertTypeToSize(dt);
      }

   int32_t spinePointerSize = (comp->target().is64Bit() && !comp->useCompressedPointers()) ? 8 : 4;
   int32_t arrayHeaderSize = TR::Compiler->om.discontiguousArrayHeaderSizeInBytes();
   int32_t arrayletMask = fej9->getArrayletMask(elementSize);

   TR::MemoryReference *spineMR;

   // Load the arraylet from the spine.
   //
   if (indexReg)
      {
      TR::InstOpCode::Mnemonic op = comp->target().is64Bit() ? TR::InstOpCode::MOVSXReg8Reg4 : TR::InstOpCode::MOVRegReg();
      generateRegRegInstruction(op, node, scratchReg, indexReg, cg);

      int32_t spineShift = fej9->getArraySpineShift(elementSize);
      generateRegImmInstruction(TR::InstOpCode::SARRegImm1(), node, scratchReg, spineShift, cg);

      spineMR =
         generateX86MemoryReference(
            baseArrayReg,
            scratchReg,
            TR::MemoryReference::convertMultiplierToStride(spinePointerSize),
            arrayHeaderSize,
            cg);
      }
   else
      {
      int32_t spineIndex = fej9->getArrayletLeafIndex(indexValue, elementSize);
      int32_t spineDisp32 = (spineIndex * spinePointerSize) + arrayHeaderSize;

      spineMR = generateX86MemoryReference(baseArrayReg, spineDisp32, cg);
      }

   TR::InstOpCode::Mnemonic op = (spinePointerSize == 8) ? TR::InstOpCode::L8RegMem : TR::InstOpCode::L4RegMem;
   generateRegMemInstruction(op, node, scratchReg, spineMR, cg);

   // Decompress the arraylet pointer from the spine.
   int32_t shiftOffset = 0;

   if (comp->target().is64Bit() && comp->useCompressedPointers())
      {
      shiftOffset = TR::Compiler->om.compressedReferenceShiftOffset();
      if (shiftOffset > 0)
         {
         generateRegImmInstruction(TR::InstOpCode::SHL8RegImm1, node, scratchReg, shiftOffset, cg);
         }
      }

   TR::MemoryReference *arrayletMR;

   // Calculate the offset with the arraylet for the index.
   //
   if (indexReg)
      {
      TR::Register *scratchReg2 = cg->allocateRegister();

      generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, scratchReg2, indexReg, cg);
      generateRegImmInstruction(TR::InstOpCode::ANDRegImm4(), node, scratchReg2, arrayletMask, cg);
      arrayletMR = generateX86MemoryReference(
         scratchReg,
         scratchReg2,
         TR::MemoryReference::convertMultiplierToStride(elementSize),
         cg);

      cg->stopUsingRegister(scratchReg2);
      }
   else
      {
      int32_t arrayletIndex = ((TR_J9VMBase *)fej9)->getLeafElementIndex(indexValue, elementSize);
      arrayletMR = generateX86MemoryReference(scratchReg, arrayletIndex*elementSize, cg);
      }

   cg->stopUsingRegister(scratchReg);

   if (!actualLoadOrStoreOrArrayElementNode->getOpCode().isStore())
      {
      TR::InstOpCode::Mnemonic op;

      TR::MemoryReference *highArrayletMR = NULL;
      TR::Register *highRegister = NULL;

      // If we're not loading an array shadow then this must be an effective
      // address computation on the array element (for a write barrier).
      //
      if ((!actualLoadOrStoreOrArrayElementNode->getOpCode().hasSymbolReference() ||
           !actualLoadOrStoreOrArrayElementNode->getSymbolReference()->getSymbol()->isArrayShadowSymbol()) &&
          !node->isSpineCheckWithArrayElementChild())
         {
         op = TR::InstOpCode::LEARegMem();
         }
      else
         {
         switch (dt)
            {
            case TR::Int8:   op = TR::InstOpCode::L1RegMem; break;
            case TR::Int16:  op = TR::InstOpCode::L2RegMem; break;
            case TR::Int32:  op = TR::InstOpCode::L4RegMem; break;
            case TR::Int64:
               if (comp->target().is64Bit())
                  op = TR::InstOpCode::L8RegMem;
               else
                  {
                  TR_ASSERT(loadOrStoreReg->getRegisterPair(), "expecting a register pair");

                  op = TR::InstOpCode::L4RegMem;
                  highArrayletMR = generateX86MemoryReference(*arrayletMR, 4, cg);
                  highRegister = loadOrStoreReg->getHighOrder();
                  loadOrStoreReg = loadOrStoreReg->getLowOrder();
                  }
               break;

            case TR::Float:  op = TR::InstOpCode::MOVSSRegMem; break;
            case TR::Double: op = TR::InstOpCode::MOVSDRegMem; break;

            case TR::Address:
               if (comp->target().is32Bit() || comp->useCompressedPointers())
                  op = TR::InstOpCode::L4RegMem;
               else
                  op = TR::InstOpCode::L8RegMem;
               break;

            default:
               TR_ASSERT(0, "unsupported array element load type");
               op = TR::InstOpCode::bad;
            }
         }

      generateRegMemInstruction(op, node, loadOrStoreReg, arrayletMR, cg);

      if (highArrayletMR)
         {
         generateRegMemInstruction(op, node, highRegister, highArrayletMR, cg);
         }

      // Decompress the loaded address if necessary.
      //
      if (loadNeedsDecompression)
         {
         if (comp->target().is64Bit() && comp->useCompressedPointers())
            {
            if (shiftOffset > 0)
               {
               generateRegImmInstruction(TR::InstOpCode::SHL8RegImm1, node, loadOrStoreReg, shiftOffset, cg);
               }
            }
         }
      }
   else
      {
      if (dt != TR::Address)
         {
         // movE [S + S2], value
         //
         TR::InstOpCode::Mnemonic op;
         bool needStore = true;

         switch (dt)
            {
            case TR::Int8:   op = valueReg ? TR::InstOpCode::S1MemReg : TR::InstOpCode::S1MemImm1; break;
            case TR::Int16:  op = valueReg ? TR::InstOpCode::S2MemReg : TR::InstOpCode::S2MemImm2; break;
            case TR::Int32:  op = valueReg ? TR::InstOpCode::S4MemReg : TR::InstOpCode::S4MemImm4; break;
            case TR::Int64:
               if (comp->target().is64Bit())
                  {
                  // The range of the immediate must be verified before this function to
                  // fall within a signed 32-bit integer.
                  //
                  op = valueReg ? TR::InstOpCode::S8MemReg : TR::InstOpCode::S8MemImm4;
                  }
               else
                  {
                  if (valueReg)
                     {
                     TR_ASSERT(valueReg->getRegisterPair(), "value must be a register pair");
                     generateMemRegInstruction(TR::InstOpCode::S4MemReg, node, arrayletMR, valueReg->getLowOrder(), cg);
                     generateMemRegInstruction(TR::InstOpCode::S4MemReg, node,
                        generateX86MemoryReference(*arrayletMR, 4, cg),
                        valueReg->getHighOrder(), cg);
                     }
                  else
                     {
                     TR::Node *valueChild = actualLoadOrStoreOrArrayElementNode->getSecondChild();
                     TR_ASSERT(valueChild->getOpCode().isLoadConst(), "expecting a long constant child");

                     generateMemImmInstruction(TR::InstOpCode::S4MemImm4, node, arrayletMR, valueChild->getLongIntLow(), cg);
                     generateMemImmInstruction(TR::InstOpCode::S4MemImm4, node,
                        generateX86MemoryReference(*arrayletMR, 4, cg),
                        valueChild->getLongIntHigh(), cg);
                     }

                  needStore = false;
                  }
               break;

            case TR::Float:  op = TR::InstOpCode::MOVSSMemReg; break;
            case TR::Double: op = TR::InstOpCode::MOVSDMemReg; break;

            default:
               TR_ASSERT(0, "unsupported array element store type");
               op = TR::InstOpCode::bad;
            }

         if (needStore)
            {
            if (valueReg)
               generateMemRegInstruction(op, node, arrayletMR, valueReg, cg);
            else
               {
               int32_t value = actualLoadOrStoreOrArrayElementNode->getSecondChild()->getInt();
               generateMemImmInstruction(op, node, arrayletMR, value, cg);
               }
            }
         }
      else
         {
         // lea S, [S+S2]
         TR_ASSERT(0, "OOL reference stores not supported yet");
         }
      }

   generateLabelInstruction(TR::InstOpCode::JMP4, node, restartLabel, cg);

   // -----------------------------------------------------------------------------------
   // Stop tracking virtual register usage.
   // -----------------------------------------------------------------------------------

   arrayletRef->setOutlinedPathRegisterUsageList(cg->stopRecordingRegisterUsage());

   arrayletRef->swapInstructionListsWithCompilation();

   return arrayletRef;
   }


// 32-bit float/double convert to long
//
TR::Register *J9::X86::TreeEvaluator::fpConvertToLong(TR::Node *node, TR::SymbolReference *helperSymRef, TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR_ASSERT_FATAL(comp->target().is32Bit(), "AMD64 doesn't use this logic");

   TR::Node *child = node->getFirstChild();

   if (child->getOpCode().isDouble())
      {
      TR::RegisterDependencyConditions  *deps;

      TR::Register        *doubleReg = cg->evaluate(child);
      TR::Register        *lowReg    = cg->allocateRegister(TR_GPR);
      TR::Register        *highReg   = cg->allocateRegister(TR_GPR);
      TR::RealRegister    *espReal   = cg->machine()->getRealRegister(TR::RealRegister::esp);

      deps = generateRegisterDependencyConditions((uint8_t) 0, 3, cg);
      deps->addPostCondition(lowReg, TR::RealRegister::NoReg, cg);
      deps->addPostCondition(highReg, TR::RealRegister::NoReg, cg);
      deps->addPostCondition(doubleReg, TR::RealRegister::NoReg, cg);
      deps->stopAddingConditions();

      TR::LabelSymbol *reStartLabel = TR::LabelSymbol::create(cg->trHeapMemory(),cg);   // exit routine label
      TR::LabelSymbol *CallLabel    = TR::LabelSymbol::create(cg->trHeapMemory(),cg);   // label where long (64-bit) conversion will start
      TR::LabelSymbol *StartLabel   = TR::LabelSymbol::create(cg->trHeapMemory(),cg);

      StartLabel->setStartInternalControlFlow();
      reStartLabel->setEndInternalControlFlow();

      // Attempt to convert a double in an XMM register to an integer using CVTTSD2SI.
      // If the conversion succeeds, put the integer in lowReg and sign-extend it to highReg.
      // If the conversion fails (the double is too large), call the helper.
      generateRegRegInstruction(TR::InstOpCode::CVTTSD2SIReg4Reg, node, lowReg, doubleReg, cg);
      generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, lowReg, 0x80000000, cg);

      generateLabelInstruction(TR::InstOpCode::label, node, StartLabel, cg);
      generateLabelInstruction(TR::InstOpCode::JE4, node, CallLabel, cg);

      generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, highReg ,lowReg, cg);
      generateRegImmInstruction(TR::InstOpCode::SAR4RegImm1, node, highReg , 31, cg);

      generateLabelInstruction(TR::InstOpCode::label, node, reStartLabel, deps, cg);

      TR::Register *targetRegister = cg->allocateRegisterPair(lowReg, highReg);
      TR::SymbolReference *d2l = comp->getSymRefTab()->findOrCreateRuntimeHelper(TR_IA32double2LongSSE);
      d2l->getSymbol()->getMethodSymbol()->setLinkage(TR_Helper);
      TR::Node::recreate(node, TR::lcall);
      node->setSymbolReference(d2l);
      TR_OutlinedInstructions *outlinedHelperCall = new (cg->trHeapMemory()) TR_OutlinedInstructions(node, TR::lcall, targetRegister, CallLabel, reStartLabel, cg);
      cg->getOutlinedInstructionsList().push_front(outlinedHelperCall);

      cg->decReferenceCount(child);
      node->setRegister(targetRegister);

      return targetRegister;
      }
   else
      {
      TR::Register *accReg    = NULL;
      TR::Register *lowReg    = cg->allocateRegister(TR_GPR);
      TR::Register *highReg   = cg->allocateRegister(TR_GPR);
      TR::Register *floatReg = cg->evaluate(child);

      TR::LabelSymbol *snippetLabel = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
      TR::LabelSymbol *startLabel   = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
      TR::LabelSymbol *reStartLabel = TR::LabelSymbol::create(cg->trHeapMemory(),cg);

      startLabel->setStartInternalControlFlow();
      reStartLabel->setEndInternalControlFlow();

      generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

      // These instructions must be set appropriately prior to the creation
      // of the snippet near the end of this method. Also see warnings below.
      //
      TR::X86RegMemInstruction          *loadHighInstr;    // loads the high dword of the converted long
      TR::X86RegMemInstruction          *loadLowInstr;     // loads the low dword of the converted long

      TR::MemoryReference  *tempMR = cg->machine()->getDummyLocalMR(TR::Float);
      generateMemRegInstruction(TR::InstOpCode::MOVSSMemReg, node, tempMR, floatReg, cg);
      generateMemInstruction(TR::InstOpCode::FLDMem, node, generateX86MemoryReference(*tempMR, 0, cg), cg);

      generateInstruction(TR::InstOpCode::FLDDUP, node, cg);

      // For slow conversion only, change the rounding mode on the FPU via its control word register.
      //
      TR::MemoryReference  *convertedLongMR = (cg->machine())->getDummyLocalMR(TR::Int64);

      if (cg->comp()->target().cpu.supportsFeature(OMR_FEATURE_X86_SSE3))
         {
         generateMemInstruction(TR::InstOpCode::FLSTTPMem, node, convertedLongMR, cg);
         }
      else
         {
         int16_t fpcw = comp->getJittedMethodSymbol()->usesSinglePrecisionMode() ?
               SINGLE_PRECISION_ROUND_TO_ZERO : DOUBLE_PRECISION_ROUND_TO_ZERO;
         generateMemInstruction(TR::InstOpCode::LDCWMem, node, generateX86MemoryReference(cg->findOrCreate2ByteConstant(node, fpcw), cg), cg);
         generateMemInstruction(TR::InstOpCode::FLSTPMem, node, convertedLongMR, cg);

         fpcw = comp->getJittedMethodSymbol()->usesSinglePrecisionMode() ?
               SINGLE_PRECISION_ROUND_TO_NEAREST : DOUBLE_PRECISION_ROUND_TO_NEAREST;

         generateMemInstruction(TR::InstOpCode::LDCWMem, node, generateX86MemoryReference(cg->findOrCreate2ByteConstant(node, fpcw), cg), cg);
         }

      // WARNING:
      //
      // The following load instructions are dissected in the snippet to determine the target registers.
      // If they or their format is changed, you may need to change the snippet also.
      //
      loadHighInstr = generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, highReg,
                                                generateX86MemoryReference(*convertedLongMR, 4, cg), cg);

      loadLowInstr = generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, lowReg,
                                               generateX86MemoryReference(*convertedLongMR, 0, cg), cg);

      // Jump to the snippet if the converted value is an indefinite integer; otherwise continue.
      //
      generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, highReg, INT_MIN, cg);
      generateLabelInstruction(TR::InstOpCode::JNE4, node, reStartLabel, cg);
      generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, lowReg, lowReg, cg);
      generateLabelInstruction(TR::InstOpCode::JE4, node, snippetLabel, cg);

      // Create the conversion snippet.
      //
      cg->addSnippet( new (cg->trHeapMemory()) TR::X86FPConvertToLongSnippet(reStartLabel,
                                                                             snippetLabel,
                                                                             helperSymRef,
                                                                             node,
                                                                             loadHighInstr,
                                                                             loadLowInstr,
                                                                             cg) );

      TR::RegisterDependencyConditions  *deps = generateRegisterDependencyConditions((uint8_t)0, accReg ? 3 : 2, cg);

      // Make sure the high and low long registers are assigned to something.
      //
      if (accReg)
         {
         deps->addPostCondition(accReg, TR::RealRegister::eax, cg);
         }

      deps->addPostCondition(lowReg, TR::RealRegister::NoReg, cg);
      deps->addPostCondition(highReg, TR::RealRegister::NoReg, cg);

      generateLabelInstruction(TR::InstOpCode::label, node, reStartLabel, deps, cg);

      cg->decReferenceCount(child);
      generateInstruction(TR::InstOpCode::FSTPST0, node, cg);

      TR::Register *targetRegister = cg->allocateRegisterPair(lowReg, highReg);
      node->setRegister(targetRegister);
      return targetRegister;
      }
   }

// On AMD64, all four [fd]2[il] conversions are handled here
// On IA32, both [fd]2i conversions are handled here
TR::Register *J9::X86::TreeEvaluator::f2iEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   bool doubleSource;
   bool longTarget;
   TR::InstOpCode::Mnemonic cvttOpCode;

   switch (node->getOpCodeValue())
      {
      case TR::f2i:
         cvttOpCode   = TR::InstOpCode::CVTTSS2SIReg4Reg;
         doubleSource = false;
         longTarget   = false;
         break;
      case TR::f2l:
         cvttOpCode   = TR::InstOpCode::CVTTSS2SIReg8Reg;
         doubleSource = false;
         longTarget   = true;
         break;
      case TR::d2i:
         cvttOpCode   = TR::InstOpCode::CVTTSD2SIReg4Reg;
         doubleSource = true;
         longTarget   = false;
         break;
      case TR::d2l:
         cvttOpCode   = TR::InstOpCode::CVTTSD2SIReg8Reg;
         doubleSource = true;
         longTarget   = true;
         break;
      default:
         TR_ASSERT_FATAL(0, "Unknown opcode value in f2iEvaluator");
         break;
      }
   TR_ASSERT_FATAL(cg->comp()->target().is64Bit() || !longTarget, "Incorrect opcode value in f2iEvaluator");

   TR::Node        *child          = node->getFirstChild();
   TR::Register    *sourceRegister = NULL;
   TR::Register    *targetRegister = cg->allocateRegister(TR_GPR);
   TR::LabelSymbol *startLabel     = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   TR::LabelSymbol *endLabel       = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   TR::LabelSymbol *exceptionLabel = TR::LabelSymbol::create(cg->trHeapMemory(),cg);

   sourceRegister = cg->evaluate(child);
   generateRegRegInstruction(cvttOpCode, node, targetRegister, sourceRegister, cg);

   startLabel->setStartInternalControlFlow();
   endLabel->setEndInternalControlFlow();

   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

   if (longTarget)
      {
      TR_ASSERT_FATAL(cg->comp()->target().is64Bit(), "We should only get here on AMD64");
      // We can't compare with 0x8000000000000000.
      // Instead, rotate left 1 bit and compare with 0x0000000000000001.
      generateRegInstruction(TR::InstOpCode::ROL8Reg1, node, targetRegister, cg);
      generateRegImmInstruction(TR::InstOpCode::CMP8RegImms, node, targetRegister, 1, cg);
      generateLabelInstruction(TR::InstOpCode::JE4, node, exceptionLabel, cg);
      }
   else
      {
      generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, targetRegister, INT_MIN, cg);
      generateLabelInstruction(TR::InstOpCode::JE4, node, exceptionLabel, cg);
      }

   //TODO: (omr issue #4969): Remove once support for spills in OOL paths is added
   TR::RegisterDependencyConditions  *deps = generateRegisterDependencyConditions((uint8_t)0, (uint8_t)2, cg);
   deps->addPostCondition(targetRegister, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(sourceRegister, TR::RealRegister::NoReg, cg);

      {
      TR_OutlinedInstructionsGenerator og(exceptionLabel, node, cg);
      // at this point, target is set to -INF and there can only be THREE possible results: -INF, +INF, NaN
      // compare source with ZERO
      generateRegMemInstruction(doubleSource ? TR::InstOpCode::UCOMISDRegMem : TR::InstOpCode::UCOMISSRegMem,
                                node,
                                sourceRegister,
                                generateX86MemoryReference(doubleSource ? cg->findOrCreate8ByteConstant(node, 0) : cg->findOrCreate4ByteConstant(node, 0), cg),
                                cg);
      // load max int if source is positive, note that for long case, LLONG_MAX << 1 is loaded as it will be shifted right
      generateRegMemInstruction(TR::InstOpCode::CMOVARegMem(longTarget),
                                node,
                                targetRegister,
                                generateX86MemoryReference(longTarget ? cg->findOrCreate8ByteConstant(node, LLONG_MAX << 1) : cg->findOrCreate4ByteConstant(node, INT_MAX), cg),
                                cg);
      // load zero if source is NaN
      generateRegMemInstruction(TR::InstOpCode::CMOVPRegMem(longTarget),
                                node,
                                targetRegister,
                                generateX86MemoryReference(longTarget ? cg->findOrCreate8ByteConstant(node, 0) : cg->findOrCreate4ByteConstant(node, 0), cg),
                                cg);

      generateLabelInstruction(TR::InstOpCode::JMP4, node, endLabel, cg);
      og.endOutlinedInstructionSequence();
      }

   generateLabelInstruction(TR::InstOpCode::label, node, endLabel, deps, cg);
   if (longTarget)
      {
      generateRegInstruction(TR::InstOpCode::ROR8Reg1, node, targetRegister, cg);
      }

   node->setRegister(targetRegister);
   cg->decReferenceCount(child);
   return targetRegister;
   }

TR::Register *J9::X86::TreeEvaluator::f2lEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR_ASSERT_FATAL(cg->comp()->target().is32Bit(), "AMD64 uses f2iEvaluator for this");
   return TR::TreeEvaluator::fpConvertToLong(node, cg->symRefTab()->findOrCreateRuntimeHelper(TR_IA32floatToLong), cg);
   }

TR::Register *J9::X86::TreeEvaluator::d2lEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR_ASSERT_FATAL(cg->comp()->target().is32Bit(), "AMD64 uses f2iEvaluator for this");

   return TR::TreeEvaluator::fpConvertToLong(node, cg->symRefTab()->findOrCreateRuntimeHelper(TR_IA32doubleToLong), cg);
   }

/*
 * J9 X86 specific tree evaluator table overrides
 */
extern void TEMPORARY_initJ9X86TreeEvaluatorTable(TR::CodeGenerator *cg)
   {
   OMR::TreeEvaluatorFunctionPointerTable tet = cg->getTreeEvaluatorTable();

   tet[TR::f2i] =                   TR::TreeEvaluator::f2iEvaluator;
   tet[TR::f2iu] =                  TR::TreeEvaluator::f2iEvaluator;
   tet[TR::f2l] =                   TR::TreeEvaluator::f2iEvaluator;
   tet[TR::f2lu] =                  TR::TreeEvaluator::f2iEvaluator;
   tet[TR::d2i] =                   TR::TreeEvaluator::f2iEvaluator;
   tet[TR::d2iu] =                  TR::TreeEvaluator::f2iEvaluator;
   tet[TR::d2l] =                   TR::TreeEvaluator::f2iEvaluator;
   tet[TR::d2lu] =                  TR::TreeEvaluator::f2iEvaluator;
   tet[TR::monent] =                TR::TreeEvaluator::monentEvaluator;
   tet[TR::monexit] =               TR::TreeEvaluator::monexitEvaluator;
   tet[TR::monexitfence] =          TR::TreeEvaluator::monexitfenceEvaluator;
   tet[TR::asynccheck] =            TR::TreeEvaluator::asynccheckEvaluator;
   tet[TR::instanceof] =            TR::TreeEvaluator::checkcastinstanceofEvaluator;
   tet[TR::checkcast] =             TR::TreeEvaluator::checkcastinstanceofEvaluator;
   tet[TR::checkcastAndNULLCHK] =   TR::TreeEvaluator::checkcastinstanceofEvaluator;
   tet[TR::New] =                   TR::TreeEvaluator::newEvaluator;
   tet[TR::newarray] =              TR::TreeEvaluator::newEvaluator;
   tet[TR::anewarray] =             TR::TreeEvaluator::newEvaluator;
   tet[TR::variableNew] =           TR::TreeEvaluator::newEvaluator;
   tet[TR::variableNewArray] =      TR::TreeEvaluator::newEvaluator;
   tet[TR::multianewarray] =        TR::TreeEvaluator::multianewArrayEvaluator;
   tet[TR::arraylength] =           TR::TreeEvaluator::arraylengthEvaluator;
   tet[TR::lookup] =                TR::TreeEvaluator::lookupEvaluator;
   tet[TR::exceptionRangeFence] =   TR::TreeEvaluator::exceptionRangeFenceEvaluator;
   tet[TR::NULLCHK] =               TR::TreeEvaluator::NULLCHKEvaluator;
   tet[TR::ZEROCHK] =               TR::TreeEvaluator::ZEROCHKEvaluator;
   tet[TR::ResolveCHK] =            TR::TreeEvaluator::resolveCHKEvaluator;
   tet[TR::ResolveAndNULLCHK] =     TR::TreeEvaluator::resolveAndNULLCHKEvaluator;
   tet[TR::DIVCHK] =                TR::TreeEvaluator::DIVCHKEvaluator;
   tet[TR::BNDCHK] =                TR::TreeEvaluator::BNDCHKEvaluator;
   tet[TR::ArrayCopyBNDCHK] =       TR::TreeEvaluator::ArrayCopyBNDCHKEvaluator;
   tet[TR::BNDCHKwithSpineCHK] =    TR::TreeEvaluator::BNDCHKwithSpineCHKEvaluator;
   tet[TR::SpineCHK] =              TR::TreeEvaluator::BNDCHKwithSpineCHKEvaluator;
   tet[TR::ArrayStoreCHK] =         TR::TreeEvaluator::ArrayStoreCHKEvaluator;
   tet[TR::ArrayCHK] =              TR::TreeEvaluator::ArrayCHKEvaluator;
   tet[TR::MethodEnterHook] =       TR::TreeEvaluator::conditionalHelperEvaluator;
   tet[TR::MethodExitHook] =        TR::TreeEvaluator::conditionalHelperEvaluator;
   tet[TR::allocationFence] =       TR::TreeEvaluator::NOPEvaluator;
   tet[TR::loadFence] =             TR::TreeEvaluator::barrierFenceEvaluator;
   tet[TR::storeFence] =            TR::TreeEvaluator::barrierFenceEvaluator;
   tet[TR::fullFence] =             TR::TreeEvaluator::barrierFenceEvaluator;
   tet[TR::ihbit] =                 TR::TreeEvaluator::integerHighestOneBit;
   tet[TR::ilbit] =                 TR::TreeEvaluator::integerLowestOneBit;
   tet[TR::inolz] =                 TR::TreeEvaluator::integerNumberOfLeadingZeros;
   tet[TR::inotz] =                 TR::TreeEvaluator::integerNumberOfTrailingZeros;
   tet[TR::lhbit] =                 TR::TreeEvaluator::longHighestOneBit;
   tet[TR::llbit] =                 TR::TreeEvaluator::longLowestOneBit;
   tet[TR::lnolz] =                 TR::TreeEvaluator::longNumberOfLeadingZeros;
   tet[TR::lnotz] =                 TR::TreeEvaluator::longNumberOfTrailingZeros;
   tet[TR::tstart] =                TR::TreeEvaluator::tstartEvaluator;
   tet[TR::tfinish] =               TR::TreeEvaluator::tfinishEvaluator;
   tet[TR::tabort] =                TR::TreeEvaluator::tabortEvaluator;

#if defined(TR_TARGET_32BIT)
   // 32-bit overrides
   tet[TR::f2l] =                   TR::TreeEvaluator::f2lEvaluator;
   tet[TR::f2lu] =                  TR::TreeEvaluator::f2lEvaluator;
   tet[TR::d2l] =                   TR::TreeEvaluator::d2lEvaluator;
   tet[TR::d2lu] =                  TR::TreeEvaluator::d2lEvaluator;
   tet[TR::ldiv] =                  TR::TreeEvaluator::integerPairDivEvaluator;
   tet[TR::lrem] =                  TR::TreeEvaluator::integerPairRemEvaluator;
#endif
   }


static void generateCommonLockNurseryCodes(TR::Node          *node,
                                     TR::CodeGenerator *cg,
                                     bool              monent, //true for VMmonentEvaluator, false for VMmonexitEvaluator
                                     TR::LabelSymbol    *monitorLookupCacheLabel,
                                     TR::LabelSymbol    *fallThruFromMonitorLookupCacheLabel,
                                     TR::LabelSymbol    *snippetLabel,
                                     uint32_t         &numDeps,
                                     int              &lwOffset,
                                     TR::Register      *objectClassReg,
                                     TR::Register      *&lookupOffsetReg,
                                     TR::Register      *vmThreadReg,
                                     TR::Register      *objectReg
                                     )
   {
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());
   if (comp->getOption(TR_EnableMonitorCacheLookup))
      {
      if (monent) lwOffset = 0;
      generateLabelInstruction(TR::InstOpCode::JLE4, node, monitorLookupCacheLabel, cg);
      generateLabelInstruction(TR::InstOpCode::JMP4, node, fallThruFromMonitorLookupCacheLabel, cg);

      generateLabelInstruction(TR::InstOpCode::label, node, monitorLookupCacheLabel, cg);

      lookupOffsetReg = cg->allocateRegister();
      numDeps++;

      int32_t offsetOfMonitorLookupCache = offsetof(J9VMThread, objectMonitorLookupCache);

      //generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, objectClassReg, generateX86MemoryReference(vmThreadReg, offsetOfMonitorLookupCache, cg), cg);
      generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, lookupOffsetReg, objectReg, cg);

      generateRegImmInstruction(TR::InstOpCode::SARRegImm1(comp->target().is64Bit()), node, lookupOffsetReg, trailingZeroes(TR::Compiler->om.getObjectAlignmentInBytes()), cg);

      J9JavaVM * jvm = fej9->getJ9JITConfig()->javaVM;
      generateRegImmInstruction(TR::InstOpCode::ANDRegImms(), node, lookupOffsetReg, J9VMTHREAD_OBJECT_MONITOR_CACHE_SIZE - 1, cg);
      generateRegImmInstruction(TR::InstOpCode::SHLRegImm1(), node, lookupOffsetReg, trailingZeroes(TR::Compiler->om.sizeofReferenceField()), cg);
      generateRegMemInstruction((comp->target().is64Bit() && fej9->generateCompressedLockWord()) ? TR::InstOpCode::L4RegMem : TR::InstOpCode::LRegMem(), node, objectClassReg, generateX86MemoryReference(vmThreadReg, lookupOffsetReg, 0, offsetOfMonitorLookupCache, cg), cg);

      generateRegRegInstruction(TR::InstOpCode::TESTRegReg(), node, objectClassReg, objectClassReg, cg);
      generateLabelInstruction(TR::InstOpCode::JE4, node, snippetLabel, cg);

      int32_t offsetOfMonitor = offsetof(J9ObjectMonitor, monitor);
      generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, lookupOffsetReg, generateX86MemoryReference(objectClassReg, offsetOfMonitor, cg), cg);

      int32_t offsetOfUserData = offsetof(J9ThreadAbstractMonitor, userData);
      generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, lookupOffsetReg, generateX86MemoryReference(lookupOffsetReg, offsetOfUserData, cg), cg);

      generateRegRegInstruction(TR::InstOpCode::CMPRegReg(), node, lookupOffsetReg, objectReg, cg);
      generateLabelInstruction(TR::InstOpCode::JNE4, node, snippetLabel, cg);

      int32_t offsetOfAlternateLockWord = offsetof(J9ObjectMonitor, alternateLockword);
      //generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, lookupOffsetReg, generateX86MemoryReference(objectClassReg, offsetOfAlternateLockWord, cg), cg);
      generateRegImmInstruction(TR::InstOpCode::ADDRegImms(), node, objectClassReg, offsetOfAlternateLockWord, cg);
      //generateRegRegInstruction(TR::InstOpCode::ADDRegReg(), node, objectClassReg, lookupOffsetReg, cg);
      generateRegRegInstruction(TR::InstOpCode::SUBRegReg(), node, objectClassReg, objectReg, cg);

      generateLabelInstruction(TR::InstOpCode::label, node, fallThruFromMonitorLookupCacheLabel, cg);
      }
   else
      generateLabelInstruction(TR::InstOpCode::JLE4, node, snippetLabel, cg);
   }

#ifdef TR_TARGET_32BIT
TR::Register *J9::X86::I386::TreeEvaluator::conditionalHelperEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // used by asynccheck, methodEnterhook, and methodExitHook

   // Decrement the reference count on the constant placeholder parameter to
   // the MethodEnterHook call.  An evaluation isn't necessary because the
   // constant value isn't used here.
   //
   if (node->getOpCodeValue() == TR::MethodEnterHook)
      {
      if (node->getSecondChild()->getOpCode().isCall() &&
          node->getSecondChild()->getNumChildren() > 1)
         {
         cg->decReferenceCount(node->getSecondChild()->getFirstChild());
         }
      }

   // The child contains an inline test.
   //
   TR::Node *testNode = node->getFirstChild();
   TR::Node *secondChild = testNode->getSecondChild();
   if (secondChild->getOpCode().isLoadConst() &&
       secondChild->getRegister() == NULL)
      {
      int32_t      value            = secondChild->getInt();
      TR::Node     *firstChild       = testNode->getFirstChild();
      TR::InstOpCode::Mnemonic opCode;
      if (value >= -128 && value <= 127)
         opCode = TR::InstOpCode::CMP4MemImms;
      else
         opCode = TR::InstOpCode::CMP4MemImm4;
      TR::MemoryReference * memRef =  generateX86MemoryReference(firstChild, cg);
      generateMemImmInstruction(opCode, node, memRef, value, cg);
      memRef->decNodeReferenceCounts(cg);
      cg->decReferenceCount(secondChild);
      }
   else
      {
      TR_X86CompareAnalyser  temp(cg);
      temp.integerCompareAnalyser(testNode, TR::InstOpCode::CMP4RegReg, TR::InstOpCode::CMP4RegMem, TR::InstOpCode::CMP4MemReg);
      }

   TR::LabelSymbol *startLabel   = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   TR::LabelSymbol *reStartLabel = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   TR::LabelSymbol *snippetLabel = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   startLabel->setStartInternalControlFlow();
   reStartLabel->setEndInternalControlFlow();
   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);
   generateLabelInstruction(testNode->getOpCodeValue() == TR::icmpeq ? TR::InstOpCode::JE4 : TR::InstOpCode::JNE4, node, snippetLabel, cg);

   TR::Snippet *snippet;
   if (node->getNumChildren() == 2)
      snippet = new (cg->trHeapMemory()) TR::X86HelperCallSnippet(cg, reStartLabel, snippetLabel, node->getSecondChild());
   else
      snippet = new (cg->trHeapMemory()) TR::X86HelperCallSnippet(cg, node, reStartLabel, snippetLabel, node->getSymbolReference());

   cg->addSnippet(snippet);

   generateLabelInstruction(TR::InstOpCode::label, node, reStartLabel, cg);
   cg->decReferenceCount(testNode);
   return NULL;
   }
#endif

#ifdef TR_TARGET_64BIT
TR::Register *J9::X86::AMD64::TreeEvaluator::conditionalHelperEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // TODO:AMD64: Try to common this with the IA32 version

   // used by asynccheck, methodEnterHook, and methodExitHook

   // The trees for TR::MethodEnterHook are expected to look like one of the following only:
   //
   // (1)   Static Method
   //
   //       TR::MethodEnterHook
   //          icmpne
   //             iload eventFlags (VM Thread)
   //             iconst 0
   //          vcall (jitReportMethodEnter)
   //             aconst (RAM method)
   //
   // (2)   Virtual Method
   //
   //       TR::MethodEnterHook
   //          icmpne
   //             iload eventFlags (VM Thread)
   //             iconst 0
   //          vcall (jitReportMethodEnter)
   //             aload (receiver parameter)
   //             aconst (RAM method)
   //
   //
   // The tree for TR::MethodExitHook is expected to look like the following:
   //
   //    TR::MethodExitHook
   //       icmpne
   //          iload (MethodExitHook table entry)
   //          iconst 0
   //       vcall (jitReportMethodExit)
   //          aconst (RAM method)
   //

   // The child contains an inline test.
   //
   TR::Node *testNode    = node->getFirstChild();
   TR::Node *secondChild = testNode->getSecondChild();
   bool testIs64Bit     = TR::TreeEvaluator::getNodeIs64Bit(secondChild, cg);
   bool testIsEQ        = testNode->getOpCodeValue() == TR::icmpeq || testNode->getOpCodeValue() == TR::lcmpeq;

   TR::Register *thisReg = NULL;
   TR::Register *ramMethodReg = NULL;

   // The receiver and RAM method parameters must be evaluated outside of the internal control flow region if it is commoned,
   // and their registers added to the post dependency condition on the merge label.
   //
   // The reference counts will be decremented when the call node is evaluated.
   //
   if (node->getOpCodeValue() == TR::MethodEnterHook || node->getOpCodeValue() == TR::MethodExitHook)
      {
      TR::Node *callNode = node->getSecondChild();

      if (callNode->getNumChildren() > 1)
         {
         if (callNode->getFirstChild()->getReferenceCount() > 1)
            thisReg = cg->evaluate(callNode->getFirstChild());

         if (callNode->getSecondChild()->getReferenceCount() > 1)
            ramMethodReg = cg->evaluate(callNode->getSecondChild());
         }
      else
         {
         if (callNode->getFirstChild()->getReferenceCount() > 1)
            ramMethodReg = cg->evaluate(callNode->getFirstChild());
         }
      }

   if (secondChild->getOpCode().isLoadConst() &&
       secondChild->getRegister() == NULL &&
       (!testIs64Bit || IS_32BIT_SIGNED(secondChild->getLongInt())))
      {
      // Try to compare memory directly with immediate
      //
      TR::MemoryReference * memRef = generateX86MemoryReference(testNode->getFirstChild(), cg);
      TR::InstOpCode::Mnemonic op;

      if (testIs64Bit)
         {
         int64_t value = secondChild->getLongInt();
         op = IS_8BIT_SIGNED(value) ? TR::InstOpCode::CMP8MemImms : TR::InstOpCode::CMP8MemImm4;
         generateMemImmInstruction(op, node, memRef, value, cg);
         }
      else
         {
         int32_t value = secondChild->getInt();
         op = IS_8BIT_SIGNED(value) ? TR::InstOpCode::CMP4MemImms : TR::InstOpCode::CMP4MemImm4;
         generateMemImmInstruction(op, node, memRef, value, cg);
         }

      memRef->decNodeReferenceCounts(cg);
      cg->decReferenceCount(secondChild);
      }
   else
      {
      TR_X86CompareAnalyser  temp(cg);
      temp.integerCompareAnalyser(testNode, TR::InstOpCode::CMPRegReg(testIs64Bit), TR::InstOpCode::CMPRegMem(testIs64Bit), TR::InstOpCode::CMPMemReg(testIs64Bit));
      }

   TR::LabelSymbol *startLabel   = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   TR::LabelSymbol *reStartLabel = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   TR::LabelSymbol *snippetLabel = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   startLabel->setStartInternalControlFlow();
   reStartLabel->setEndInternalControlFlow();

   TR::Instruction *startInstruction = generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

   if (node->getOpCodeValue() == TR::MethodEnterHook || node->getOpCodeValue() == TR::MethodExitHook)
      {
      TR::Node *callNode = node->getSecondChild();

      // Generate an inverted jump around the call.  This is necessary because we want to do the call inline rather
      // than through the snippet.
      //
      generateLabelInstruction(testIsEQ ? TR::InstOpCode::JNE4 : TR::InstOpCode::JE4, node, reStartLabel, cg);
      TR::TreeEvaluator::performCall(callNode, false, false, cg);

      // Collect postconditions from the internal control flow region and put
      // them on the restart label to prevent spills in the internal control
      // flow region.
      // TODO:AMD64: This would be a useful general facility to have.
      //
      TR::Machine *machine = cg->machine();
      TR::RegisterDependencyConditions  *postConditions = new (cg->trHeapMemory()) TR::RegisterDependencyConditions((uint8_t)0, TR::RealRegister::NumRegisters, cg->trMemory());
      if (thisReg)
         postConditions->addPostCondition(thisReg, TR::RealRegister::NoReg, cg);

      if (ramMethodReg)
         postConditions->addPostCondition(ramMethodReg, TR::RealRegister::NoReg, cg);

      for (TR::Instruction *cursor = cg->getAppendInstruction(); cursor != startInstruction; cursor = cursor->getPrev())
         {
         TR::RegisterDependencyConditions  *cursorDeps = cursor->getDependencyConditions();
         if (cursorDeps && cursor->getOpCodeValue() != TR::InstOpCode::assocreg)
            {
            if (debug("traceConditionalHelperEvaluator"))
               {
               diagnostic("conditionalHelperEvaluator: Adding deps from " POINTER_PRINTF_FORMAT "\n", cursor);
               }
            for (int32_t i = 0; i < cursorDeps->getNumPostConditions(); i++)
               {
               TR::RegisterDependency  *cursorPostCondition = cursorDeps->getPostConditions()->getRegisterDependency(i);
               postConditions->unionPostCondition(cursorPostCondition->getRegister(), cursorPostCondition->getRealRegister(), cg);
               if (debug("traceConditionalHelperEvaluator"))
                  {
                  TR_Debug *debug = cg->getDebug();
                  diagnostic("conditionalHelperEvaluator:    [%s : %s]\n", debug->getName(cursorPostCondition->getRegister()), debug->getName(machine->getRealRegister(cursorPostCondition->getRealRegister())));
                  }
               }
            }
         }
      postConditions->stopAddingPostConditions();

      generateLabelInstruction(TR::InstOpCode::label, node, reStartLabel, postConditions, cg);
      }
   else
      {
      generateLabelInstruction(testIsEQ? TR::InstOpCode::JE4 : TR::InstOpCode::JNE4, node, snippetLabel, cg);

      TR::Snippet *snippet;
      if (node->getNumChildren() == 2)
         snippet = new (cg->trHeapMemory()) TR::X86HelperCallSnippet(cg, reStartLabel, snippetLabel, node->getSecondChild());
      else
         snippet = new (cg->trHeapMemory()) TR::X86HelperCallSnippet(cg, node, reStartLabel, snippetLabel, node->getSymbolReference());

      cg->addSnippet(snippet);
      generateLabelInstruction(TR::InstOpCode::label, node, reStartLabel, cg);
      }

   cg->decReferenceCount(testNode);
   return NULL;
   }
#endif

TR::Register* J9::X86::TreeEvaluator::performHeapLoadWithReadBarrier(TR::Node* node, TR::CodeGenerator* cg)
   {
#ifndef OMR_GC_CONCURRENT_SCAVENGER
   TR_ASSERT_FATAL(0, "Concurrent Scavenger not supported.");
   return NULL;
#else
   TR::Compilation *comp = cg->comp();
   bool use64BitClasses = comp->target().is64Bit() && !comp->useCompressedPointers();

   TR::MemoryReference* sourceMR = generateX86MemoryReference(node, cg);
   TR::Register* address = TR::TreeEvaluator::loadMemory(node, sourceMR, TR_RematerializableLoadEffectiveAddress, false, cg);
   address->setMemRef(sourceMR);
   sourceMR->decNodeReferenceCounts(cg);

   TR::Register* object = cg->allocateRegister();
   TR::Instruction* load = generateRegMemInstruction(TR::InstOpCode::LRegMem(use64BitClasses), node, object, generateX86MemoryReference(address, 0, cg), cg);
   cg->setImplicitExceptionPoint(load);

   switch (TR::Compiler->om.readBarrierType())
      {
      case gc_modron_readbar_none:
         TR_ASSERT(false, "This path should only be reached when a read barrier is required.");
         break;
      case gc_modron_readbar_always:
         generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, floatTemp1), cg), address, cg);
         generateHelperCallInstruction(node, TR_softwareReadBarrier, NULL, cg);
         generateRegMemInstruction(TR::InstOpCode::LRegMem(use64BitClasses), node, object, generateX86MemoryReference(address, 0, cg), cg);
         break;
      case gc_modron_readbar_range_check:
         {
         TR::LabelSymbol* begLabel = generateLabelSymbol(cg);
         TR::LabelSymbol* endLabel = generateLabelSymbol(cg);
         TR::LabelSymbol* rdbarLabel = generateLabelSymbol(cg);
         begLabel->setStartInternalControlFlow();
         endLabel->setEndInternalControlFlow();

         TR::RegisterDependencyConditions* deps = generateRegisterDependencyConditions((uint8_t)2, 2, cg);
         deps->addPreCondition(object, TR::RealRegister::NoReg, cg);
         deps->addPreCondition(address, TR::RealRegister::NoReg, cg);
         deps->addPostCondition(object, TR::RealRegister::NoReg, cg);
         deps->addPostCondition(address, TR::RealRegister::NoReg, cg);

         generateLabelInstruction(TR::InstOpCode::label, node, begLabel, cg);
         generateRegMemInstruction(TR::InstOpCode::CMPRegMem(use64BitClasses), node, object, generateX86MemoryReference(cg->getVMThreadRegister(), comp->fej9()->thisThreadGetEvacuateBaseAddressOffset(), cg), cg);
         generateLabelInstruction(TR::InstOpCode::JAE4, node, rdbarLabel, cg);
         {
         TR_OutlinedInstructionsGenerator og(rdbarLabel, node, cg);
         generateRegMemInstruction(TR::InstOpCode::CMPRegMem(use64BitClasses), node, object, generateX86MemoryReference(cg->getVMThreadRegister(), comp->fej9()->thisThreadGetEvacuateTopAddressOffset(), cg), cg);
         generateLabelInstruction(TR::InstOpCode::JA4, node, endLabel, cg);
         generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, floatTemp1), cg), address, cg);
         generateHelperCallInstruction(node, TR_softwareReadBarrier, NULL, cg);
         generateRegMemInstruction(TR::InstOpCode::LRegMem(use64BitClasses), node, object, generateX86MemoryReference(address, 0, cg), cg);
         generateLabelInstruction(TR::InstOpCode::JMP4, node, endLabel, cg);
         og.endOutlinedInstructionSequence();
         }
         generateLabelInstruction(TR::InstOpCode::label, node, endLabel, deps, cg);
         }
         break;
      default:
         TR_ASSERT(false, "Unsupported Read Barrier Type.");
         break;
      }
   cg->stopUsingRegister(address);
   return object;
#endif
   }

// Should only be called for pure TR::awrtbar and TR::awrtbari nodes.
//
TR::Register *J9::X86::TreeEvaluator::writeBarrierEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR::MemoryReference *storeMR = generateX86MemoryReference(node, cg);
   TR::Node               *destOwningObject;
   TR::Node               *sourceObject;
   TR::Compilation *comp = cg->comp();
   bool                   usingCompressedPointers = false;
   bool                   useShiftedOffsets = (TR::Compiler->om.compressedReferenceShiftOffset() != 0);

   if (node->getOpCodeValue() == TR::awrtbari)
      {
      destOwningObject = node->getChild(2);
      sourceObject = node->getSecondChild();
      if (comp->useCompressedPointers() &&
          (node->getSymbolReference()->getSymbol()->getDataType() == TR::Address) &&
          (node->getSecondChild()->getDataType() != TR::Address))
         {
         usingCompressedPointers = true;

         if (useShiftedOffsets)
            {
            while ((sourceObject->getNumChildren() > 0) && (sourceObject->getOpCodeValue() != TR::a2l))
               sourceObject = sourceObject->getFirstChild();
            if (sourceObject->getOpCodeValue() == TR::a2l)
               sourceObject = sourceObject->getFirstChild();
            // this is required so that different registers are
            // allocated for the actual store and translated values
            sourceObject->incReferenceCount();
            }
         }
      }
   else
      {
      TR_ASSERT((node->getOpCodeValue() == TR::awrtbar), "expecting a TR::wrtbar");
      destOwningObject = node->getSecondChild();
      sourceObject = node->getFirstChild();
      }

   TR_X86ScratchRegisterManager *scratchRegisterManager =
      cg->generateScratchRegisterManager(comp->target().is64Bit() ? 15 : 7);

   TR::TreeEvaluator::VMwrtbarWithStoreEvaluator(
      node,
      storeMR,
      scratchRegisterManager,
      destOwningObject,
      sourceObject,
      (node->getOpCodeValue() == TR::awrtbari) ? true : false,
      cg,
      false);

   if (comp->useAnchors() && (node->getOpCodeValue() == TR::awrtbari))
      node->setStoreAlreadyEvaluated(true);

   if (usingCompressedPointers)
      cg->decReferenceCount(node->getSecondChild());

   return NULL;
   }


TR::Register *J9::X86::TreeEvaluator::monentEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   if (cg->enableRematerialisation() &&
       cg->supportsStaticMemoryRematerialization())
      TR::TreeEvaluator::removeLiveDiscardableStatics(cg);

   return TR::TreeEvaluator::VMmonentEvaluator(node, cg);
   }

TR::Register *J9::X86::TreeEvaluator::monexitEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   if (cg->enableRematerialisation() &&
       cg->supportsStaticMemoryRematerialization())
      TR::TreeEvaluator::removeLiveDiscardableStatics(cg);

   return TR::TreeEvaluator::VMmonexitEvaluator(node, cg);
   }

TR::Register *J9::X86::TreeEvaluator::asynccheckEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // Generate the test and branch for async message processing.
   //
   TR::Node *compareNode = node->getFirstChild();
   TR::Node *secondChild = compareNode->getSecondChild();
   TR::LabelSymbol *snippetLabel = generateLabelSymbol(cg);
   TR::Compilation *comp = cg->comp();

   if (comp->getOption(TR_RTGCMapCheck))
      {
      TR::TreeEvaluator::asyncGCMapCheckPatching(node, cg, snippetLabel);
      }
   else
      {
      TR_ASSERT_FATAL(secondChild->getOpCode().isLoadConst(), "unrecognized asynccheck test: special async check value is not a constant");

      TR::MemoryReference *mr = generateX86MemoryReference(compareNode->getFirstChild(), cg);
      if ((secondChild->getRegister() != NULL) ||
          (comp->target().is64Bit() && !IS_32BIT_SIGNED(secondChild->getLongInt())))
         {
         TR::Register *valueReg = cg->evaluate(secondChild);
         TR::X86CheckAsyncMessagesMemRegInstruction *ins =
            generateCheckAsyncMessagesInstruction(node, TR::InstOpCode::CMPMemReg(), mr, valueReg, cg);
         }
      else
         {
         int32_t value = secondChild->getInt();
         TR::InstOpCode::Mnemonic op = (value < 127 && value >= -128) ? TR::InstOpCode::CMPMemImms() : TR::InstOpCode::CMPMemImm4();
         TR::X86CheckAsyncMessagesMemImmInstruction *ins =
            generateCheckAsyncMessagesInstruction(node, op, mr, value, cg);
         }

      mr->decNodeReferenceCounts(cg);
      cg->decReferenceCount(secondChild);
      }

   TR::LabelSymbol *startControlFlowLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *endControlFlowLabel = generateLabelSymbol(cg);

   bool testIsEqual = compareNode->getOpCodeValue() == TR::icmpeq || compareNode->getOpCodeValue() == TR::lcmpeq;

   TR_ASSERT(testIsEqual, "unrecognized asynccheck test: test is not equal");

   startControlFlowLabel->setStartInternalControlFlow();
   generateLabelInstruction(TR::InstOpCode::label, node, startControlFlowLabel, cg);

   generateLabelInstruction(testIsEqual ? TR::InstOpCode::JE4 : TR::InstOpCode::JNE4, node, snippetLabel, cg);

   {
   TR_OutlinedInstructionsGenerator og(snippetLabel, node, cg);
   generateImmSymInstruction(TR::InstOpCode::CALLImm4, node, (uintptr_t)node->getSymbolReference()->getMethodAddress(), node->getSymbolReference(), cg)->setNeedsGCMap(0xFF00FFFF);
   generateLabelInstruction(TR::InstOpCode::JMP4, node, endControlFlowLabel, cg);
   og.endOutlinedInstructionSequence();
   }

   endControlFlowLabel->setEndInternalControlFlow();
   generateLabelInstruction(TR::InstOpCode::label, node, endControlFlowLabel, cg);

   cg->decReferenceCount(compareNode);

   return NULL;
   }

// Handles newObject, newArray, anewArray
//
TR::Register *J9::X86::TreeEvaluator::newEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR::Register *targetRegister = NULL;

   if (TR::TreeEvaluator::requireHelperCallValueTypeAllocation(node, cg))
      {
      TR_OpaqueClassBlock *classInfo;
      bool spillFPRegs = comp->canAllocateInlineOnStack(node, classInfo) <= 0;
      return TR::TreeEvaluator::performHelperCall(node, NULL, TR::acall, spillFPRegs, cg);
      }

   targetRegister = TR::TreeEvaluator::VMnewEvaluator(node, cg);
   if (!targetRegister)
      {
      // Inline object allocation wasn't generated, just generate a call to the helper.
      // If we know that the class is fully initialized, we don't have to spill
      // the FP registers.
      //
      TR_OpaqueClassBlock *classInfo;
      bool spillFPRegs = (comp->canAllocateInlineOnStack(node, classInfo) <= 0);
      targetRegister = TR::TreeEvaluator::performHelperCall(node, NULL, TR::acall, spillFPRegs, cg);
      }
   else if (cg->canEmitBreakOnDFSet())
      {
      // Check DF flag after inline new
      generateBreakOnDFSet(cg);
      }

   return targetRegister;
   }

/**
 * Generate code for multianewarray
 *
 * Includes inline allocation for arrays where the size of the first or second dimension is 0.
 *
 * NB Must only be used for arrays of at least two dimensions
*/
static TR::Register * generateMultianewArrayWithInlineAllocators(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();

   TR::Node *firstChild = node->getFirstChild();      // ptr to array of sizes, one for each dimension. Array construction stops at the outermost zero size
   TR::Node *secondChild = node->getSecondChild();    // Number of dimensions - this is fixed in the bytecode, so compile time constant
   TR::Node *thirdChild = node->getThirdChild();      // class of the outermost dimension

   // 2-dimensional MultiANewArray
   TR_J9VMBase *fej9 = comp->fej9();

   TR::Register *dimsPtrReg = NULL;
   TR::Register *dimReg = NULL;
   TR::Register *classReg = NULL;
   TR::Register *firstDimLenReg = NULL;
   TR::Register *secondDimLenReg = NULL;
   TR::Register *targetReg = NULL;
   TR::Register *temp1Reg = NULL;
   TR::Register *temp2Reg = NULL;
   TR::Register *temp3Reg = NULL;
   TR::Register *componentClassReg = NULL;
   TR::Register *vmThreadReg = cg->getVMThreadRegister();

   targetReg = cg->allocateRegister();
   firstDimLenReg = cg->allocateRegister();
   secondDimLenReg = cg->allocateRegister();
   temp1Reg = cg->allocateRegister();
   temp2Reg = cg->allocateRegister();
   temp3Reg = cg->allocateRegister();
   componentClassReg = cg->allocateRegister();

   TR::LabelSymbol *startLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *doneLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *loopLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *nonZeroFirstDimLabel = generateLabelSymbol(cg);
#if defined(J9VM_GC_SPARSE_HEAP_ALLOCATION)
   bool isOffHeapAllocationEnabled = TR::Compiler->om.isOffHeapAllocationEnabled();
#endif /* defined(J9VM_GC_SPARSE_HEAP_ALLOCATION) */

   startLabel->setStartInternalControlFlow();
   doneLabel->setEndInternalControlFlow();

   TR::LabelSymbol *oolFailLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *oolJumpPoint = generateLabelSymbol(cg);

   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

   // Generate the heap allocation, and the snippet that will handle heap overflow.
   TR_OutlinedInstructions *outlinedHelperCall = new (cg->trHeapMemory()) TR_OutlinedInstructions(node, TR::acall, targetReg, oolFailLabel, doneLabel, cg);
   cg->getOutlinedInstructionsList().push_front(outlinedHelperCall);

   dimReg = cg->evaluate(secondChild);
   dimsPtrReg = cg->evaluate(firstChild);
   classReg = cg->evaluate(thirdChild);

   // inlined code for allocating zero length arrays where the zero len is in either the first or second dimension

   generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, secondDimLenReg,
                             generateX86MemoryReference(dimsPtrReg, 0, cg), cg);
   // Load the 32-bit length value as a 64-bit value so that the top half of the register
   // can be zeroed out. This will allow us to treat the value as 64-bit when performing
   // calculations later on.
   generateRegMemInstruction(TR::InstOpCode::MOVSXReg8Mem4, node, firstDimLenReg,
                             generateX86MemoryReference(dimsPtrReg, 4, cg), cg);

   generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, secondDimLenReg, 0, cg);

   generateLabelInstruction(TR::InstOpCode::JNE4, node, oolJumpPoint, cg);
   // Second Dim length is 0

   generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, firstDimLenReg, 0, cg);
   generateLabelInstruction(TR::InstOpCode::JNE4, node, nonZeroFirstDimLabel, cg);

   // First Dim zero, only allocate 1 zero-length object array
   generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, targetReg, generateX86MemoryReference(vmThreadReg, offsetof(J9VMThread, heapAlloc), cg), cg);

   // Take into account alignment requirements for the size of the zero-length array header
   int32_t zeroArraySizeAligned = OMR::align(TR::Compiler->om.discontiguousArrayHeaderSizeInBytes(), TR::Compiler->om.getObjectAlignmentInBytes());
   generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, temp1Reg, generateX86MemoryReference(targetReg, zeroArraySizeAligned, cg), cg);

   generateRegMemInstruction(TR::InstOpCode::CMPRegMem(), node, temp1Reg, generateX86MemoryReference(vmThreadReg, offsetof(J9VMThread, heapTop), cg), cg);
   generateLabelInstruction(TR::InstOpCode::JA4, node, oolJumpPoint, cg);
   generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, generateX86MemoryReference(vmThreadReg, offsetof(J9VMThread, heapAlloc), cg), temp1Reg, cg);

   // Init class
   bool use64BitClasses = comp->target().is64Bit() && !TR::Compiler->om.generateCompressedObjectHeaders();
   generateMemRegInstruction(TR::InstOpCode::SMemReg(use64BitClasses), node, generateX86MemoryReference(targetReg, TR::Compiler->om.offsetOfObjectVftField(), cg), classReg, cg);

   // Init size and mustBeZero ('0') fields to 0
   generateMemImmInstruction(TR::InstOpCode::S4MemImm4, node, generateX86MemoryReference(targetReg, fej9->getOffsetOfContiguousArraySizeField(), cg), 0, cg);
   generateMemImmInstruction(TR::InstOpCode::S4MemImm4, node, generateX86MemoryReference(targetReg, fej9->getOffsetOfDiscontiguousArraySizeField(), cg), 0, cg);

#if defined(J9VM_GC_SPARSE_HEAP_ALLOCATION)
   if (isOffHeapAllocationEnabled)
      {
      // Init 1st dim dataAddr slot to 0
      generateMemImmInstruction(TR::InstOpCode::S8MemImm4, node, generateX86MemoryReference(targetReg, fej9->getOffsetOfDiscontiguousDataAddrField(), cg), 0, cg);
      }
#endif /* J9VM_GC_SPARSE_HEAP_ALLOCATION */
   generateLabelInstruction(TR::InstOpCode::JMP4, node, doneLabel, cg);

   //First dim length not 0
   generateLabelInstruction(TR::InstOpCode::label, node, nonZeroFirstDimLabel, cg);

   generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, componentClassReg,
            generateX86MemoryReference(classReg, offsetof(J9ArrayClass, componentType), cg), cg);

   int32_t elementSize = TR::Compiler->om.sizeofReferenceField();

   uintptr_t maxObjectSize = cg->getMaxObjectSizeGuaranteedNotToOverflow();
   uintptr_t maxObjectSizeInElements = maxObjectSize / elementSize;
   generateRegImmInstruction(TR::InstOpCode::CMPRegImm4(), node, firstDimLenReg, static_cast<int32_t>(maxObjectSizeInElements), cg);

   // Must be an unsigned comparison on sizes.
   generateLabelInstruction(TR::InstOpCode::JAE4, node, oolJumpPoint, cg);

   generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, temp1Reg, firstDimLenReg, cg);

   int32_t elementSizeAligned = OMR::align(elementSize, TR::Compiler->om.getObjectAlignmentInBytes());
   int32_t alignmentCompensation = (elementSize == elementSizeAligned) ? 0 : elementSizeAligned - 1;

   TR_ASSERT_FATAL(elementSize <= 8, "multianewArrayEvaluator - elementSize cannot be greater than 8!");
   generateRegImmInstruction(TR::InstOpCode::SHLRegImm1(), node, temp1Reg, TR::MemoryReference::convertMultiplierToStride(elementSize), cg);
   generateRegImmInstruction(TR::InstOpCode::ADDRegImm4(), node, temp1Reg, TR::Compiler->om.contiguousArrayHeaderSizeInBytes()+alignmentCompensation, cg);

   if (alignmentCompensation != 0)
      {
      generateRegImmInstruction(TR::InstOpCode::ANDRegImm4(), node, temp1Reg, -elementSizeAligned, cg);
      }

   TR_ASSERT_FATAL(zeroArraySizeAligned >= 0 && zeroArraySizeAligned <= 127, "discontiguousArrayHeaderSizeInBytes cannot be > 127 for IMulRegRegImms instruction");
   generateRegRegImmInstruction(TR::InstOpCode::IMULRegRegImm4(), node, temp2Reg, firstDimLenReg, zeroArraySizeAligned, cg);

   // temp2Reg = temp2Reg + temp1Reg
   generateRegRegInstruction(TR::InstOpCode::ADDRegReg(), node, temp2Reg, temp1Reg, cg);

   generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, targetReg, generateX86MemoryReference(vmThreadReg, offsetof(J9VMThread, heapAlloc), cg), cg);
   // temp2Reg = temp2Reg + J9VMThread->heapAlloc
   generateRegRegInstruction(TR::InstOpCode::ADDRegReg(), node, temp2Reg, targetReg, cg);

   generateRegMemInstruction(TR::InstOpCode::CMPRegMem(), node, temp2Reg, generateX86MemoryReference(vmThreadReg, offsetof(J9VMThread, heapTop), cg), cg);
   generateLabelInstruction(TR::InstOpCode::JA4, node, oolJumpPoint, cg);
   generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, generateX86MemoryReference(vmThreadReg, offsetof(J9VMThread, heapAlloc), cg), temp2Reg, cg);

   //init 1st dim array class field
   generateMemRegInstruction(TR::InstOpCode::SMemReg(use64BitClasses), node, generateX86MemoryReference(targetReg, TR::Compiler->om.offsetOfObjectVftField(), cg), classReg, cg);
   // Init 1st dim array size field
   generateMemRegInstruction(TR::InstOpCode::S4MemReg, node, generateX86MemoryReference(targetReg, fej9->getOffsetOfContiguousArraySizeField(), cg), firstDimLenReg, cg);
#if defined(J9VM_GC_SPARSE_HEAP_ALLOCATION)
   if (isOffHeapAllocationEnabled)
      {
      /* Populate dataAddr slot of 1st dimension array. Arrays of non-zero size
       * use contiguous header layout while zero size arrays use discontiguous header layout.
       */
      generateRegMemInstruction(TR::InstOpCode::LEARegMem(),
         node,
         temp3Reg,
         generateX86MemoryReference(targetReg, TR::Compiler->om.contiguousArrayHeaderSizeInBytes(), cg),
         cg);
      generateMemRegInstruction(TR::InstOpCode::SMemReg(),
         node,
         generateX86MemoryReference(targetReg, fej9->getOffsetOfContiguousDataAddrField(), cg),
         temp3Reg,
         cg);
      }
#endif /* J9VM_GC_SPARSE_HEAP_ALLOCATION */

   // temp2 point to end of 1st dim array i.e. start of 2nd dim
   generateRegRegInstruction(TR::InstOpCode::MOVRegReg(),  node, temp2Reg, targetReg, cg);
   generateRegRegInstruction(TR::InstOpCode::ADDRegReg(), node, temp2Reg, temp1Reg, cg);
   // temp1 points to 1st dim array past header
   generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, temp1Reg, generateX86MemoryReference(targetReg, TR::Compiler->om.contiguousArrayHeaderSizeInBytes(), cg), cg);

   //loop start
   generateLabelInstruction(TR::InstOpCode::label, node, loopLabel, cg);
   // Init 2nd dim element's class
   generateMemRegInstruction(TR::InstOpCode::SMemReg(use64BitClasses), node, generateX86MemoryReference(temp2Reg, TR::Compiler->om.offsetOfObjectVftField(), cg), componentClassReg, cg);
   // Init 2nd dim element's size and mustBeZero ('0') fields to 0
   generateMemImmInstruction(TR::InstOpCode::S4MemImm4, node, generateX86MemoryReference(temp2Reg, fej9->getOffsetOfContiguousArraySizeField(), cg), 0, cg);
   generateMemImmInstruction(TR::InstOpCode::S4MemImm4, node, generateX86MemoryReference(temp2Reg, fej9->getOffsetOfDiscontiguousArraySizeField(), cg), 0, cg);

#if defined(J9VM_GC_SPARSE_HEAP_ALLOCATION)
   if (isOffHeapAllocationEnabled)
      {
      // Populate dataAddr slot for 2nd dimension zero size array.
      generateMemImmInstruction(TR::InstOpCode::S8MemImm4, node, generateX86MemoryReference(temp2Reg, fej9->getOffsetOfDiscontiguousDataAddrField(), cg), 0, cg);
      }
#endif /* J9VM_GC_SPARSE_HEAP_ALLOCATION */

   // Store 2nd dim element into 1st dim array slot, compress temp2 if needed
   if (comp->target().is64Bit() && comp->useCompressedPointers())
      {
      int32_t shiftAmount = TR::Compiler->om.compressedReferenceShift();
      generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, temp3Reg, temp2Reg, cg);
      if (shiftAmount != 0)
         {
         generateRegImmInstruction(TR::InstOpCode::SHRRegImm1(), node, temp3Reg, shiftAmount, cg);
         }
      generateMemRegInstruction(TR::InstOpCode::S4MemReg, node, generateX86MemoryReference(temp1Reg, 0, cg), temp3Reg, cg);
      }
   else
      {
      generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, generateX86MemoryReference(temp1Reg, 0, cg), temp2Reg, cg);
      }

   // Advance cursors temp1 and temp2
   generateRegImmInstruction(TR::InstOpCode::ADDRegImms(), node, temp2Reg, zeroArraySizeAligned, cg);
   generateRegImmInstruction(TR::InstOpCode::ADDRegImms(), node, temp1Reg, elementSize, cg);

   generateRegInstruction(TR::InstOpCode::DEC4Reg, node, firstDimLenReg, cg);
   generateLabelInstruction(TR::InstOpCode::JA4, node, loopLabel, cg);

   generateLabelInstruction(TR::InstOpCode::JMP4, node, doneLabel, cg);

   TR::RegisterDependencyConditions  *deps = generateRegisterDependencyConditions((uint8_t)0, 13, cg);

   deps->addPostCondition(dimsPtrReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(dimReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(classReg, TR::RealRegister::NoReg, cg);

   deps->addPostCondition(firstDimLenReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(secondDimLenReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(temp1Reg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(temp2Reg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(temp3Reg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(componentClassReg, TR::RealRegister::NoReg, cg);

   deps->addPostCondition(targetReg, TR::RealRegister::eax, cg);
   deps->addPostCondition(cg->getVMThreadRegister(), TR::RealRegister::ebp, cg);

   TR::Node *callNode = outlinedHelperCall->getCallNode();
   TR::Register *reg;

   if (callNode->getFirstChild() == node->getFirstChild())
      {
      reg = callNode->getFirstChild()->getRegister();
      if (reg)
         deps->unionPostCondition(reg, TR::RealRegister::NoReg, cg);
      }

   if (callNode->getSecondChild() == node->getSecondChild())
      {
      reg = callNode->getSecondChild()->getRegister();
      if (reg)
         deps->unionPostCondition(reg, TR::RealRegister::NoReg, cg);
      }

   if (callNode->getThirdChild() == node->getThirdChild())
      {
      reg = callNode->getThirdChild()->getRegister();
      if (reg)
         deps->unionPostCondition(reg, TR::RealRegister::NoReg, cg);
      }

   deps->stopAddingConditions();

   generateLabelInstruction(TR::InstOpCode::label, node, oolJumpPoint, cg);
   generateLabelInstruction(TR::InstOpCode::JMP4, node, oolFailLabel, cg);

   generateLabelInstruction(TR::InstOpCode::label, node, doneLabel, deps, cg);

   // Copy the newly allocated object into a collected reference register now that it is a valid object.
   //
   TR::Register *targetReg2 = cg->allocateCollectedReferenceRegister();
   TR::RegisterDependencyConditions  *deps2 = generateRegisterDependencyConditions(0, 1, cg);
   deps2->addPostCondition(targetReg2, TR::RealRegister::eax, cg);
   generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, targetReg2, targetReg, deps2, cg);
   cg->stopUsingRegister(targetReg);
   targetReg = targetReg2;

   cg->stopUsingRegister(firstDimLenReg);
   cg->stopUsingRegister(secondDimLenReg);
   cg->stopUsingRegister(temp1Reg);
   cg->stopUsingRegister(temp2Reg);
   cg->stopUsingRegister(temp3Reg);
   cg->stopUsingRegister(componentClassReg);

   // Decrement use counts on the children
   //
   cg->decReferenceCount(node->getFirstChild());
   cg->decReferenceCount(node->getSecondChild());
   cg->decReferenceCount(node->getThirdChild());

   node->setRegister(targetReg);
   return targetReg;
}

/**
 * Generate code for multianewarray
 *
 * Checks the number of dimensions. For 1 dimensional arrays call the helper, for >1 call
 * generateMultianewArrayWithInlineAllocators.
*/
TR::Register *J9::X86::TreeEvaluator::multianewArrayEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {

   TR::Compilation *comp = cg->comp();
   TR_ASSERT_FATAL(comp->target().is64Bit(), "multianewArrayEvaluator is only supported on 64-bit JVMs!");

   TR::Node *secondChild = node->getSecondChild();    // Number of dimensions - this is fixed in the bytecode, so compile time constant

   // The number of dimensions should always be an iconst
   TR_ASSERT_FATAL(secondChild->getOpCodeValue() == TR::iconst, "dims of multianewarray must be iconst");

   // Only generate inline code if nDims > 1
   uint32_t nDims = secondChild->get32bitIntegralValue();
   if (nDims > 1)
      {
      return generateMultianewArrayWithInlineAllocators(node, cg);
      }
   else
      {
      // trace a message to indicate that inline allocation is disabled for nDims < 2
      if (comp->getOption(TR_TraceCG))
         {
         traceMsg(comp, "Disabling inline allocations for multianewarray of dim %d\n", nDims);
         }
      TR::ILOpCodes opCode = node->getOpCodeValue();
      TR::Node::recreate(node, TR::acall);
      TR::Register *targetRegister = directCallEvaluator(node, cg);
      TR::Node::recreate(node, opCode);
      return targetRegister;
      }

   }

TR::Register *J9::X86::TreeEvaluator::arraycopyEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   if (cg->canEmitBreakOnDFSet())
      generateBreakOnDFSet(cg);

   TR::Compilation *comp = cg->comp();

   if (!node->isReferenceArrayCopy())
      {
      return OMR::TreeEvaluatorConnector::arraycopyEvaluator(node, cg);
      }

   auto srcObjReg = cg->evaluate(node->getChild(0));
   auto dstObjReg = cg->evaluate(node->getChild(1));
   auto srcReg    = cg->evaluate(node->getChild(2));
   auto dstReg    = cg->evaluate(node->getChild(3));
   auto sizeReg   = cg->evaluate(node->getChild(4));

#if defined(J9VM_GC_SPARSE_HEAP_ALLOCATION)
   if (TR::Compiler->om.isOffHeapAllocationEnabled())
      // For correct card-marking calculation, the dstObjNode should be the baseObj not the dataAddrPointer
      TR_ASSERT_FATAL(!node->getChild(1)->isDataAddrPointer(), "The byteDstObjNode child of arraycopy cannot be a dataAddrPointer");
#endif /* defined(J9VM_GC_SPARSE_HEAP_ALLOCATION) */

   if (comp->target().is64Bit() && !TR::TreeEvaluator::getNodeIs64Bit(node->getChild(4), cg))
      {
      generateRegRegInstruction(TR::InstOpCode::MOVZXReg8Reg4, node, sizeReg, sizeReg, cg);
      }

   if (!node->isNoArrayStoreCheckArrayCopy())
      {
      // Nothing to optimize, simply call jitReferenceArrayCopy helper
      auto deps = generateRegisterDependencyConditions((uint8_t)3, 3, cg);
      deps->addPreCondition(srcReg, TR::RealRegister::esi, cg);
      deps->addPreCondition(dstReg, TR::RealRegister::edi, cg);
      deps->addPreCondition(sizeReg, TR::RealRegister::ecx, cg);
      deps->addPostCondition(srcReg, TR::RealRegister::esi, cg);
      deps->addPostCondition(dstReg, TR::RealRegister::edi, cg);
      deps->addPostCondition(sizeReg, TR::RealRegister::ecx, cg);

      generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, floatTemp1), cg), srcObjReg, cg);
      generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, floatTemp2), cg), dstObjReg, cg);
      generateHelperCallInstruction(node, TR_referenceArrayCopy, deps, cg)->setNeedsGCMap(0xFF00FFFF);

      auto snippetLabel = generateLabelSymbol(cg);
      auto instr = generateLabelInstruction(TR::InstOpCode::JNE4, node, snippetLabel, cg); // ReferenceArrayCopy set ZF when succeed.
      auto snippet = new (cg->trHeapMemory()) TR::X86CheckFailureSnippet(cg, cg->symRefTab()->findOrCreateRuntimeHelper(TR_arrayStoreException),
                                                                         snippetLabel, instr, false);
      cg->addSnippet(snippet);
      }
   else
      {
      bool use64BitClasses = comp->target().is64Bit() && !TR::Compiler->om.generateCompressedObjectHeaders();

      auto RSI = cg->allocateRegister();
      auto RDI = cg->allocateRegister();
      auto RCX = cg->allocateRegister();

      TR::Register* tmpReg1 = NULL;
      TR::Register* tmpReg2 = NULL;
      TR::Register* tmpXmmYmmReg1 = NULL;
      TR::Register* tmpXmmYmmReg2 = NULL;

      static bool disableReferenceArrayCopyInlineSmallSizeWithoutREPMOVS  = feGetEnv("TR_DisableReferenceArrayCopyInlineSmallSizeWithoutREPMOVS") != NULL;

      bool enableInlineForSmallSize = !disableReferenceArrayCopyInlineSmallSizeWithoutREPMOVS &&
                                      !comp->getOption(TR_DisableReferenceArrayCopyInlineSmallSizeWithoutREPMOVS) &&
                                      comp->target().cpu.supportsAVX() &&
                                      comp->target().is64Bit();

      int32_t repMovsThresholdBytes = 32;
      int32_t newThreshold = comp->getOptions()->getArraycopyRepMovsReferenceArrayThreshold();

      if ((repMovsThresholdBytes < newThreshold) && ((newThreshold == 64) || (newThreshold == 128)))
         {
         // If the CPU doesn't support AVX512, reduce the threshold to 64 bytes
         repMovsThresholdBytes = ((newThreshold == 128) && cg->getMaxPreferredVectorLength() != TR::VectorLength512) ? 64 : newThreshold;
         }

      if (enableInlineForSmallSize)
         {
         tmpReg1 = cg->allocateRegister(TR_GPR);
         tmpReg2 = cg->allocateRegister(TR_GPR);
         tmpXmmYmmReg1 = cg->allocateRegister(TR_VRF);
         tmpXmmYmmReg2 = cg->allocateRegister(TR_VRF);
         }

      generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, RSI, srcReg, cg);
      generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, RDI, dstReg, cg);
      generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, RCX, sizeReg, cg);

      int8_t numDeps = enableInlineForSmallSize ? 9 : 5;
      TR::RegisterDependencyConditions* deps = generateRegisterDependencyConditions(numDeps, numDeps, cg);

      deps->addPreCondition(RSI, TR::RealRegister::esi, cg);
      deps->addPreCondition(RDI, TR::RealRegister::edi, cg);
      deps->addPreCondition(RCX, TR::RealRegister::ecx, cg);
      deps->addPreCondition(srcObjReg, TR::RealRegister::NoReg, cg);
      deps->addPreCondition(dstObjReg, TR::RealRegister::NoReg, cg);
      deps->addPostCondition(RSI, TR::RealRegister::esi, cg);
      deps->addPostCondition(RDI, TR::RealRegister::edi, cg);
      deps->addPostCondition(RCX, TR::RealRegister::ecx, cg);
      deps->addPostCondition(srcObjReg, TR::RealRegister::NoReg, cg);
      deps->addPostCondition(dstObjReg, TR::RealRegister::NoReg, cg);

      if (enableInlineForSmallSize)
         {
         deps->addPreCondition(tmpReg1, TR::RealRegister::NoReg, cg);
         deps->addPreCondition(tmpReg2, TR::RealRegister::NoReg, cg);
         deps->addPreCondition(tmpXmmYmmReg1, TR::RealRegister::NoReg, cg);
         deps->addPreCondition(tmpXmmYmmReg2, TR::RealRegister::NoReg, cg);

         deps->addPostCondition(tmpReg1, TR::RealRegister::NoReg, cg);
         deps->addPostCondition(tmpReg2, TR::RealRegister::NoReg, cg);
         deps->addPostCondition(tmpXmmYmmReg1, TR::RealRegister::NoReg, cg);
         deps->addPostCondition(tmpXmmYmmReg2, TR::RealRegister::NoReg, cg);
         }

      auto begLabel = generateLabelSymbol(cg);
      auto endLabel = generateLabelSymbol(cg);
      begLabel->setStartInternalControlFlow();
      endLabel->setEndInternalControlFlow();

      generateLabelInstruction(TR::InstOpCode::label, node, begLabel, cg);

      if (TR::Compiler->om.readBarrierType() != gc_modron_readbar_none)
         {
         bool use64BitClasses = comp->target().is64Bit() && !comp->useCompressedPointers();

         TR::LabelSymbol* rdbarLabel = generateLabelSymbol(cg);
         // EvacuateTopAddress == 0 means Concurrent Scavenge is inactive
         generateMemImmInstruction(TR::InstOpCode::CMPMemImms(use64BitClasses), node, generateX86MemoryReference(cg->getVMThreadRegister(), comp->fej9()->thisThreadGetEvacuateTopAddressOffset(), cg), 0, cg);
         generateLabelInstruction(TR::InstOpCode::JNE4, node, rdbarLabel, cg);

         TR_OutlinedInstructionsGenerator og(rdbarLabel, node, cg);
         generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, floatTemp1), cg), srcObjReg, cg);
         generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, floatTemp2), cg), dstObjReg, cg);
         generateHelperCallInstruction(node, TR_referenceArrayCopy, NULL, cg)->setNeedsGCMap(0xFF00FFFF);
         generateLabelInstruction(TR::InstOpCode::JMP4, node, endLabel, cg);
         og.endOutlinedInstructionSequence();
         }

      if (enableInlineForSmallSize)
         {
         TR::LabelSymbol* repMovsLabel = generateLabelSymbol(cg);

         if (use64BitClasses)
            {
            OMR::TreeEvaluatorConnector::arrayCopy64BitPrimitiveInlineSmallSizeWithoutREPMOVSImplRoot16(node, RDI /* dstReg */, RSI /* srcReg */, RCX /* sizeReg */, tmpReg1, tmpReg2,
                                                                                                        tmpXmmYmmReg1, tmpXmmYmmReg2, cg, repMovsThresholdBytes, repMovsLabel, endLabel);
            }
         else
            {
            OMR::TreeEvaluatorConnector::arrayCopy32BitPrimitiveInlineSmallSizeWithoutREPMOVSImplRoot16(node, RDI /* dstReg */, RSI /* srcReg */, RCX /* sizeReg */, tmpReg1, tmpReg2,
                                                                                                        tmpXmmYmmReg1, tmpXmmYmmReg2, cg, repMovsThresholdBytes, repMovsLabel, endLabel);
            }

         generateLabelInstruction(TR::InstOpCode::label, node, repMovsLabel, cg);
         }

      if (!node->isForwardArrayCopy())
         {
         TR::LabelSymbol* backwardLabel = generateLabelSymbol(cg);

         generateRegRegInstruction(TR::InstOpCode::SUBRegReg(), node, RDI, RSI, cg); // dst = dst - src
         generateRegRegInstruction(TR::InstOpCode::CMPRegReg(), node, RDI, RCX, cg); // cmp dst, size
         generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, RDI, generateX86MemoryReference(RDI, RSI, 0, cg), cg); // dst = dst + src
         generateLabelInstruction(TR::InstOpCode::JB4, node, backwardLabel, cg);     // jb, skip backward copy setup

         TR_OutlinedInstructionsGenerator og(backwardLabel, node, cg);
         generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, RSI, generateX86MemoryReference(RSI, RCX, 0, -TR::Compiler->om.sizeofReferenceField(), cg), cg);
         generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, RDI, generateX86MemoryReference(RDI, RCX, 0, -TR::Compiler->om.sizeofReferenceField(), cg), cg);
         generateRegImmInstruction(TR::InstOpCode::SHRRegImm1(), node, RCX, use64BitClasses ? 3 : 2, cg);
         generateInstruction(TR::InstOpCode::STD, node, cg);
         generateInstruction(use64BitClasses ? TR::InstOpCode::REPMOVSQ : TR::InstOpCode::REPMOVSD, node, cg);
         generateInstruction(TR::InstOpCode::CLD, node, cg);
         generateLabelInstruction(TR::InstOpCode::JMP4, node, endLabel, cg);
         og.endOutlinedInstructionSequence();
         }

      generateRegImmInstruction(TR::InstOpCode::SHRRegImm1(), node, RCX, use64BitClasses ? 3 : 2, cg);
      generateInstruction(use64BitClasses ? TR::InstOpCode::REPMOVSQ : TR::InstOpCode::REPMOVSD, node, cg);

      generateLabelInstruction(TR::InstOpCode::label, node, endLabel, deps, cg);

      cg->stopUsingRegister(RSI);
      cg->stopUsingRegister(RDI);
      cg->stopUsingRegister(RCX);

      if (enableInlineForSmallSize)
         {
         cg->stopUsingRegister(tmpReg1);
         cg->stopUsingRegister(tmpReg2);
         cg->stopUsingRegister(tmpXmmYmmReg1);
         cg->stopUsingRegister(tmpXmmYmmReg2);
         }

      TR::TreeEvaluator::VMwrtbarWithoutStoreEvaluator(node, node->getChild(1), NULL, NULL, cg->generateScratchRegisterManager(), cg);
      }

   for (int32_t i = 0; i < node->getNumChildren(); i++)
      {
      cg->decReferenceCount(node->getChild(i));
      }
   return NULL;
   }

TR::Register *J9::X86::TreeEvaluator::arraylengthEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());
   // MOV R, [B + contiguousSize]
   // TEST R, R
   // CMOVE R, [B + discontiguousSize]
   //
   TR::Register *objectReg = cg->evaluate(node->getFirstChild());
   TR::Register *lengthReg = cg->allocateRegister();

   TR::MemoryReference *contiguousArraySizeMR =
      generateX86MemoryReference(objectReg, fej9->getOffsetOfContiguousArraySizeField(), cg);

   TR::MemoryReference *discontiguousArraySizeMR =
      generateX86MemoryReference(objectReg, fej9->getOffsetOfDiscontiguousArraySizeField(), cg);

   generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, lengthReg, contiguousArraySizeMR, cg);
   generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, lengthReg, lengthReg, cg);
   generateRegMemInstruction(TR::InstOpCode::CMOVE4RegMem, node, lengthReg, discontiguousArraySizeMR, cg);

   cg->decReferenceCount(node->getFirstChild());
   node->setRegister(lengthReg);
   return lengthReg;
   }

TR::Register *J9::X86::TreeEvaluator::exceptionRangeFenceEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   generateFenceInstruction(TR::InstOpCode::fence, node, node, cg);
   return NULL;
   }


TR::Register *J9::X86::TreeEvaluator::evaluateNULLCHKWithPossibleResolve(
   TR::Node          *node,
   bool              needResolution,
   TR::CodeGenerator *cg)
   {
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());
   static bool disableBranchlessPassThroughNULLCHK = feGetEnv("TR_disableBranchlessPassThroughNULLCHK") != NULL;
   // NOTE:
   //
   // If no code is generated for the null check, just evaluate the
   // child and decrement its use count UNLESS the child is a pass-through node
   // in which case some kind of explicit test or indirect load must be generated
   // to force the null check at this point.
   //
   TR::Node *firstChild = node->getFirstChild();
   TR::Node *reference  = NULL;
   TR::Compilation *comp = cg->comp();

   bool usingCompressedPointers = false;

   if (comp->useCompressedPointers() &&
       firstChild->getOpCodeValue() == TR::l2a)
      {
      // pattern match the sequence under the l2a
      // NULLCHK        NULLCHK                     <- node
      //    aloadi f      l2a
      //       aload O       ladd
      //                       lshl
      //                          i2l
      //                            iloadi/irdbari f <- firstChild
      //                               aload O        <- reference
      //                          iconst shftKonst
      //                       lconst HB
      //
      usingCompressedPointers = true;

      TR::ILOpCodes loadOp = comp->il.opCodeForIndirectLoad(TR::Int32);
      TR::ILOpCodes rdbarOp = comp->il.opCodeForIndirectReadBarrier(TR::Int32);
      while (firstChild->getOpCodeValue() != loadOp && firstChild->getOpCodeValue() != rdbarOp)
         firstChild = firstChild->getFirstChild();
      reference = firstChild->getFirstChild();
      }
   else
      reference = node->getNullCheckReference();

   TR::ILOpCode &opCode = firstChild->getOpCode();

   // Skip the NULLCHK for TR::loadaddr nodes.
   //
   if (reference->getOpCodeValue() == TR::loadaddr)
      {
      if (usingCompressedPointers)
         firstChild = node->getFirstChild();
      cg->evaluate(firstChild);
      cg->decReferenceCount(firstChild);
      return NULL;
      }

   bool needExplicitCheck  = true;
   bool needLateEvaluation = true;

   // Add the explicit check after this instruction
   //
   TR::Instruction *appendTo = 0;

   if (opCode.isLoadVar() || (comp->target().is64Bit() && opCode.getOpCodeValue()==TR::l2i))
      {
      TR::SymbolReference *symRef = NULL;

      if (opCode.getOpCodeValue()==TR::l2i)
         {
         symRef = firstChild->getFirstChild()->getSymbolReference();
         }
      else
         symRef = firstChild->getSymbolReference();

      if (symRef &&
          (symRef->getSymbol()->getOffset() + symRef->getOffset() < cg->getNumberBytesReadInaccessible()))
         {
         needExplicitCheck = false;

         // If the child is an arraylength which has been reduced to an iloadi,
         // and is only going to be used immediately in a bound check then combine the checks.
         //
         TR::TreeTop *nextTreeTop = cg->getCurrentEvaluationTreeTop()->getNextTreeTop();
         if (firstChild->getReferenceCount() == 2 && nextTreeTop)
            {
            TR::Node *nextTopNode = nextTreeTop->getNode();

            if (nextTopNode)
               {
               if (nextTopNode->getOpCode().isBndCheck() || nextTopNode->getOpCode().isSpineCheck())
                  {
                  bool doIt = false;

                  if (nextTopNode->getOpCodeValue() == TR::SpineCHK)
                     {
                     // Implicit NULLCHKs and SpineCHKs can be merged if the base array
                     // is the same.
                     //
                     if (firstChild->getOpCode().isIndirect() && firstChild->getOpCode().isLoadVar())
                        {
                        if (nextTopNode->getChild(1) == firstChild->getFirstChild())
                           doIt = true;
                        }
                     }
                  else
                     {
                     int32_t arrayLengthChildNum = (nextTopNode->getOpCodeValue() == TR::BNDCHKwithSpineCHK) ? 2 : 0;

                     if (nextTopNode->getChild(arrayLengthChildNum) == firstChild)
                        doIt = true;
                     }

                  if (doIt &&
                     performTransformation(comp,
                     "\nMerging NULLCHK [" POINTER_PRINTF_FORMAT "] and BNDCHK/SpineCHK [" POINTER_PRINTF_FORMAT "] of load child [" POINTER_PRINTF_FORMAT "]\n",
                      node, nextTopNode, firstChild))
                     {
                     needLateEvaluation = false;
                     nextTopNode->setHasFoldedImplicitNULLCHK(true);
                     }
                  }
               else if (nextTopNode->getOpCode().isIf() &&
                        nextTopNode->isNonoverriddenGuard() &&
                        nextTopNode->getFirstChild() == firstChild)
                  {
                  needLateEvaluation = false;
                  needExplicitCheck = true;
                  reference->incReferenceCount(); // will be decremented again later
                  }
               }
            }
         }
      else if (firstChild->getReferenceCount() == 1 && !firstChild->getSymbolReference()->isUnresolved())
         {
         // If the child is only used here, we don't need to evaluate it
         // since all we need is the grandchild which will be evaluated by
         // the generation of the explicit check below.
         //
         needLateEvaluation = false;

         // at this point, firstChild is the raw iloadi (created by lowerTrees) and
         // reference is the aload of the object. node->getFirstChild is the
         // l2a sequence; as a result, firstChild's refCount will always be 1
         // and node->getFirstChild's refCount will be at least 2 (one under the nullchk
         // and the other under the translate treetop)
         //
         if (usingCompressedPointers && node->getFirstChild()->getReferenceCount() >= 2)
            needLateEvaluation = true;
         }
      }
   else if (opCode.isStore())
      {
      TR::SymbolReference *symRef = firstChild->getSymbolReference();
      if (symRef &&
          symRef->getSymbol()->getOffset() + symRef->getOffset() < cg->getNumberBytesWriteInaccessible())
         {
         needExplicitCheck = false;
         }
      }
   else if (opCode.isCall()     &&
            opCode.isIndirect() &&
            cg->getNumberBytesReadInaccessible() > TR::Compiler->om.offsetOfObjectVftField())
      {
      needExplicitCheck = false;
      }
   else if (opCode.getOpCodeValue() == TR::monent ||
            opCode.getOpCodeValue() == TR::monexit)
      {
      // The child may generate inline code that provides an implicit null check
      // but we won't know until the child is evaluated.
      //
      reference->incReferenceCount(); // will be decremented again later
      needLateEvaluation = false;
      cg->evaluate(reference);
      appendTo = cg->getAppendInstruction();
      cg->evaluate(firstChild);

      // TODO: this shouldn't be getOffsetOfContiguousArraySizeField
      //
      if (cg->getImplicitExceptionPoint() &&
          cg->getNumberBytesReadInaccessible() > fej9->getOffsetOfContiguousArraySizeField())
         {
         needExplicitCheck = false;
         cg->decReferenceCount(reference);
         }
      }
   else if (!disableBranchlessPassThroughNULLCHK && opCode.getOpCodeValue () == TR::PassThrough
            && !needResolution && cg->getHasResumableTrapHandler())
      {
      TR::Register *refRegister = cg->evaluate(firstChild);
      needLateEvaluation = false;

      if (refRegister)
         {
         if (!appendTo)
            appendTo = cg->getAppendInstruction();
         if (cg->getNumberBytesReadInaccessible() > 0)
            {
            needExplicitCheck = false;
            TR::MemoryReference *memRef = NULL;
            if (TR::Compiler->om.compressedReferenceShift() > 0
                && firstChild->getType() == TR::Address
                && firstChild->getOpCode().hasSymbolReference()
                && firstChild->getSymbol()->isCollectedReference())
               {
               memRef = generateX86MemoryReference(NULL, refRegister, TR::Compiler->om.compressedReferenceShift(), 0, cg);
               }
            else
               {
               memRef = generateX86MemoryReference(refRegister, 0, cg);
               }
            appendTo = generateMemImmInstruction(appendTo, TR::InstOpCode::TEST1MemImm1, memRef, 0, cg);
            cg->setImplicitExceptionPoint(appendTo);
            }
         }
      }

   // Generate the code for the null check.
   //
   if (needExplicitCheck)
      {
      // TODO - If a resolve check is needed as well, the resolve must be done
      // before the null check, so that exceptions are handled in the correct
      // order.
      //
      ///// if (needResolution)
      /////    {
      /////    ...
      /////    }

      // Avoid loading the grandchild into a register if it is not going to be used again.
      //
      if (opCode.getOpCodeValue() == TR::PassThrough &&
          reference->getOpCode().isLoadVar() &&
          reference->getRegister() == NULL &&
          reference->getReferenceCount() == 1)
         {
         TR::MemoryReference *tempMR = generateX86MemoryReference(reference, cg);

         if (!appendTo)
             appendTo = cg->getAppendInstruction();

         TR::InstOpCode::Mnemonic op = TR::InstOpCode::CMPMemImms();
         appendTo = generateMemImmInstruction(appendTo, op, tempMR, NULLVALUE, cg);
         tempMR->decNodeReferenceCounts(cg);
         needLateEvaluation = false;
         }
      else
         {
         TR::Register *targetRegister = cg->evaluate(reference);

         if (!appendTo)
            appendTo = cg->getAppendInstruction();

         appendTo = generateRegRegInstruction(appendTo, TR::InstOpCode::TESTRegReg(), targetRegister, targetRegister, cg);
         }

      TR::LabelSymbol *snippetLabel = generateLabelSymbol(cg);
      appendTo = generateLabelInstruction(appendTo, TR::InstOpCode::JE4, snippetLabel, cg);
      //the _node field should point to the current node
      appendTo->setNode(node);
      appendTo->setLiveLocals(cg->getLiveLocals());

      TR::Snippet *snippet;
      if (opCode.isCall() || !needResolution || comp->target().is64Bit()) //TODO:AMD64: Implement the "withresolve" version
         {
         snippet = new (cg->trHeapMemory()) TR::X86CheckFailureSnippet(cg, node->getSymbolReference(),
                                                                 snippetLabel, appendTo);
         }
      else
         {
         TR_RuntimeHelper resolverCall;
         TR::Machine *machine = cg->machine();
         TR::Symbol * firstChildSym = firstChild->getSymbolReference()->getSymbol();

         if (firstChildSym->isShadow())
            {
            resolverCall = opCode.isStore() ?
               TR_X86interpreterUnresolvedFieldSetterGlue : TR_X86interpreterUnresolvedFieldGlue;
            }
         else if (firstChildSym->isClassObject())
            {
            resolverCall = firstChildSym->addressIsCPIndexOfStatic() ?
               TR_X86interpreterUnresolvedClassFromStaticFieldGlue : TR_X86interpreterUnresolvedClassGlue;
            }
         else if (firstChildSym->isConstString())
            {
            resolverCall = TR_X86interpreterUnresolvedStringGlue;
            }
         else if (firstChildSym->isConstMethodType())
            {
            resolverCall = TR_interpreterUnresolvedMethodTypeGlue;
            }
         else if (firstChildSym->isConstMethodHandle())
            {
            resolverCall = TR_interpreterUnresolvedMethodHandleGlue;
            }
         else if (firstChildSym->isCallSiteTableEntry())
            {
            resolverCall = TR_interpreterUnresolvedCallSiteTableEntryGlue;
            }
         else if (firstChildSym->isMethodTypeTableEntry())
            {
            resolverCall = TR_interpreterUnresolvedMethodTypeTableEntryGlue;
            }
         else
            {
            resolverCall = opCode.isStore() ?
               TR_X86interpreterUnresolvedStaticFieldSetterGlue : TR_X86interpreterUnresolvedStaticFieldGlue;
            }

         snippet = new (cg->trHeapMemory()) TR::X86CheckFailureSnippetWithResolve(cg, node->getSymbolReference(),
                                                                      firstChild->getSymbolReference(),
                                                                      resolverCall,
                                                                      snippetLabel,
                                                                      appendTo);

         ((TR::X86CheckFailureSnippetWithResolve *)(snippet))->setNumLiveX87Registers(machine->fpGetNumberOfLiveFPRs());
         ((TR::X86CheckFailureSnippetWithResolve *)(snippet))->setHasLiveXMMRs();
         }

      cg->addSnippet(snippet);
      }

   // If we need to evaluate the child, do so. Otherwise, if we have
   // evaluated the reference node, then decrement its use count.
   // The use count of the child is decremented when we are done
   // evaluating the NULLCHK.
   //
   if (needLateEvaluation)
      {
      cg->evaluate(node->getFirstChild());
      }
   else if (needExplicitCheck)
      {
      cg->decReferenceCount(reference);
      }

   if (comp->useCompressedPointers())
      cg->decReferenceCount(node->getFirstChild());
   else
      cg->decReferenceCount(firstChild);

   // If an explicit check has not been generated for the null check, there is
   // an instruction that will cause a hardware trap if the exception is to be
   // taken. If this method may catch the exception, a GC stack map must be
   // created for this instruction. All registers are valid at this GC point
   // TODO - if the method may not catch the exception we still need to note
   // that the GC point exists, since maps before this point and after it cannot
   // be merged.
   //
   if (!needExplicitCheck)
      {
      TR::Instruction *faultingInstruction = cg->getImplicitExceptionPoint();
      if (faultingInstruction)
         {
         faultingInstruction->setNeedsGCMap(0xFF00FFFF);
         faultingInstruction->setNode(node);
         }
      }

   TR::Node *n = NULL;
   if (comp->useCompressedPointers() &&
         reference->getOpCodeValue() == TR::l2a)
      {
      reference->setIsNonNull(true);
      n = reference->getFirstChild();
      TR::ILOpCodes loadOp = comp->il.opCodeForIndirectLoad(TR::Int32);
      TR::ILOpCodes rdbarOp = comp->il.opCodeForIndirectReadBarrier(TR::Int32);
      while (n->getOpCodeValue() != loadOp && n->getOpCodeValue() != rdbarOp)
         {
         n->setIsNonZero(true);
         n = n->getFirstChild();
         }
      n->setIsNonZero(true);
      }

   reference->setIsNonNull(true);

   return NULL;
   }

TR::Register *J9::X86::TreeEvaluator::NULLCHKEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   return TR::TreeEvaluator::evaluateNULLCHKWithPossibleResolve(node, false, cg);
   }

TR::Register *J9::X86::TreeEvaluator::resolveAndNULLCHKEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   return TR::TreeEvaluator::evaluateNULLCHKWithPossibleResolve(node, true, cg);
   }


// Generate explicit checks for division by zero and division
// overflow (i.e. 0x80000000 / 0xFFFFFFFF), if necessary.
//
TR::Register *J9::X86::TreeEvaluator::DIVCHKEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   bool     hasConversion;
   TR::Node *divisionNode = node->getFirstChild();
   TR::Compilation *comp = cg->comp();

   TR::ILOpCodes op = divisionNode->getOpCodeValue();

   if (op == TR::iu2l ||
       op == TR::bu2i ||
       op == TR::bu2l ||
       op == TR::bu2s ||
       op == TR::su2i ||
       op == TR::su2l)
      {
      divisionNode = divisionNode->getFirstChild();
      hasConversion = true;
      }
   else
      hasConversion = false;

   bool use64BitRegisters =  comp->target().is64Bit() && divisionNode->getOpCode().isLong();
   bool useRegisterPairs  = comp->target().is32Bit() && divisionNode->getOpCode().isLong();

   // Not all targets support implicit division checks, so we generate explicit
   // tests and snippets to jump to.
   //
   bool platformNeedsExplicitCheck = !cg->enableImplicitDivideCheck();

   // Only do this for TR::ldiv/TR::lrem and TR::idiv/TR::irem by non-constant
   // divisors, or by a constant of zero.
   // Other constant divisors are optimized in signedIntegerDivOrRemAnalyser,
   // and do not cause hardware exceptions.
   //
   bool operationNeedsCheck = (divisionNode->getOpCode().isInt() &&
      (!divisionNode->getSecondChild()->getOpCode().isLoadConst() || divisionNode->getSecondChild()->getInt() == 0));
   if (use64BitRegisters)
      {
      operationNeedsCheck = operationNeedsCheck |
         ((!divisionNode->getSecondChild()->getOpCode().isLoadConst() || divisionNode->getSecondChild()->getLongInt() == 0));
      }
   else
      {
      operationNeedsCheck = operationNeedsCheck | useRegisterPairs;
      }

   if (platformNeedsExplicitCheck && operationNeedsCheck)
      {
      TR::Register *dividendReg = cg->evaluate(divisionNode->getFirstChild());
      TR::Register *divisorReg  = cg->evaluate(divisionNode->getSecondChild());

      TR::LabelSymbol *startLabel               = generateLabelSymbol(cg);
      TR::LabelSymbol *divisionLabel            = generateLabelSymbol(cg);
      TR::LabelSymbol *divideByZeroSnippetLabel = generateLabelSymbol(cg);
      TR::LabelSymbol *restartLabel             = generateLabelSymbol(cg);

      // These instructions are dissected in the divide check snippet to determine
      // the source registers. If they or their format are changed, you may need to
      // change the snippet(s) also.
      //
      TR::X86RegRegInstruction *lowDivisorTestInstr;
      TR::X86RegRegInstruction *highDivisorTestInstr;

      startLabel->setStartInternalControlFlow();
      restartLabel->setEndInternalControlFlow();

      generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

      if (useRegisterPairs)
         {
         TR::Register *tempReg = cg->allocateRegister(TR_GPR);
         lowDivisorTestInstr =  generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, tempReg, divisorReg->getLowOrder(),  cg);
         highDivisorTestInstr = generateRegRegInstruction(TR::InstOpCode::OR4RegReg,  node, tempReg, divisorReg->getHighOrder(), cg);
         generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, tempReg, tempReg, cg);
         cg->stopUsingRegister(tempReg);
         }
      else
         lowDivisorTestInstr = generateRegRegInstruction(TR::InstOpCode::TESTRegReg(use64BitRegisters), node, divisorReg, divisorReg, cg);

      generateLabelInstruction(TR::InstOpCode::JE4, node, divideByZeroSnippetLabel, cg);

      cg->addSnippet(new (cg->trHeapMemory()) TR::X86CheckFailureSnippet(cg, node->getSymbolReference(),
                                                         divideByZeroSnippetLabel,
                                                         cg->getAppendInstruction()));

      generateLabelInstruction(TR::InstOpCode::label, node, divisionLabel, cg);

      TR::Register *resultRegister = cg->evaluate(divisionNode);

      if (!hasConversion)
         cg->decReferenceCount(divisionNode);

      // We need to make sure that any spilling occurs only after restartLabel,
      // otherwise the divide check snippet may store into the wrong register.
      //
      TR::RegisterDependencyConditions  *deps = generateRegisterDependencyConditions((uint8_t) 0, 2, cg);
      TR::Register *scratchRegister;

      if (useRegisterPairs)
         {
         deps->addPostCondition(resultRegister->getLowOrder(), TR::RealRegister::eax, cg);
         deps->addPostCondition(resultRegister->getHighOrder(), TR::RealRegister::edx, cg);
         }
      else switch(divisionNode->getOpCodeValue())
         {
         case TR::idiv:
         case TR::ldiv:
            deps->addPostCondition(resultRegister, TR::RealRegister::eax, cg);
            scratchRegister = cg->allocateRegister(TR_GPR);
            deps->addPostCondition(scratchRegister, TR::RealRegister::edx, cg);
            cg->stopUsingRegister(scratchRegister);
            break;

         case TR::irem:
         case TR::lrem:
            deps->addPostCondition(resultRegister, TR::RealRegister::edx, cg);
            scratchRegister = cg->allocateRegister(TR_GPR);
            deps->addPostCondition(scratchRegister, TR::RealRegister::eax, cg);
            cg->stopUsingRegister(scratchRegister);
            break;

         default:
            TR_ASSERT(0, "bad division opcode for DIVCHK\n");
         }

      generateLabelInstruction(TR::InstOpCode::label, node, restartLabel, deps, cg);

      if (hasConversion)
         {
         cg->evaluate(node->getFirstChild());
         cg->decReferenceCount(node->getFirstChild());
         }
      }
   else
      {
      cg->evaluate(node->getFirstChild());
      cg->decReferenceCount(node->getFirstChild());

      // There may be an instruction that will cause a hardware trap if an exception
      // is to be taken.
      // If this method may catch the exception, a GC stack map must be created for
      // this instruction. All registers are valid at this GC point
      //
      // TODO: if the method may not catch the exception we still need to note
      // that the GC point exists, since maps before this point and after it cannot
      // be merged.
      //
      TR::Instruction *faultingInstruction = cg->getImplicitExceptionPoint();
      if (faultingInstruction)
         faultingInstruction->setNeedsGCMap(0xFF00FFFF);
      }

   return NULL;
   }


static bool isInteger(TR::ILOpCode &op, TR::CodeGenerator *cg)
   {
   if (cg->comp()->target().is64Bit())
      return op.isIntegerOrAddress();
   else
      return op.isIntegerOrAddress() && (op.getSize() <= 4);
   }


static TR::InstOpCode::Mnemonic branchOpCodeForCompare(TR::ILOpCode &op, bool opposite=false)
   {
   int32_t index = 0;
   if (op.isCompareTrueIfLess())
      index += 1;
   if (op.isCompareTrueIfGreater())
      index += 2;
   if (op.isCompareTrueIfEqual())
      index += 4;
   if (op.isUnsignedCompare())
      index += 8;

   if (opposite)
      index ^= 7;

   static const TR::InstOpCode::Mnemonic opTable[] =
      {
      TR::InstOpCode::bad,  TR::InstOpCode::JL4,  TR::InstOpCode::JG4,  TR::InstOpCode::JNE4,
      TR::InstOpCode::JE4,        TR::InstOpCode::JLE4, TR::InstOpCode::JGE4, TR::InstOpCode::bad,
      TR::InstOpCode::bad,  TR::InstOpCode::JB4,  TR::InstOpCode::JA4,  TR::InstOpCode::JNE4,
      TR::InstOpCode::JE4,        TR::InstOpCode::JBE4, TR::InstOpCode::JAE4, TR::InstOpCode::bad,
      };
   return opTable[index];
   }


TR::Register *J9::X86::TreeEvaluator::ZEROCHKEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // NOTE: ZEROCHK is intended to be general and straightforward.  If you're
   // thinking of adding special code for specific situations in here, consider
   // whether you want to add your own CHK opcode instead.  If you feel the
   // need for special handling here, you may also want special handling in the
   // optimizer, in which case a separate opcode may be more suitable.
   //
   // On the other hand, if the improvements you're adding could benefit other
   // users of ZEROCHK, please go ahead and add them!
   //
   // If in doubt, discuss your design with your team lead.

   TR::LabelSymbol *slowPathLabel = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   TR::LabelSymbol *restartLabel  = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   slowPathLabel->setStartInternalControlFlow();
   restartLabel->setEndInternalControlFlow();
   TR::Compilation *comp = cg->comp();

   // Temporarily hide the first child so it doesn't appear in the outlined call
   //
   node->rotateChildren(node->getNumChildren()-1, 0);
   node->setNumChildren(node->getNumChildren()-1);

   // Outlined instructions for check failure
   // Note: we don't pass the restartLabel in here because we don't want a
   // restart branch.
   //
   TR_OutlinedInstructions *outlinedHelperCall = new (cg->trHeapMemory()) TR_OutlinedInstructions(node, TR::call, NULL, slowPathLabel, NULL, cg);
   cg->getOutlinedInstructionsList().push_front(outlinedHelperCall);
   cg->generateDebugCounter(
         outlinedHelperCall->getFirstInstruction(),
         TR::DebugCounter::debugCounterName(comp, "helperCalls/%s/(%s)/%d/%d", node->getOpCode().getName(), comp->signature(), node->getByteCodeInfo().getCallerIndex(), node->getByteCodeInfo().getByteCodeIndex()),
         1, TR::DebugCounter::Cheap);

   // Restore the first child
   //
   node->setNumChildren(node->getNumChildren()+1);
   node->rotateChildren(0, node->getNumChildren()-1);

   // Children other than the first are only for the outlined path; we don't need them here
   //
   for (int32_t i = 1; i < node->getNumChildren(); i++)
      cg->recursivelyDecReferenceCount(node->getChild(i));

   // In-line instructions for the check
   //
   TR::Node *valueToCheck = node->getFirstChild();
   if ( valueToCheck->getOpCode().isBooleanCompare()
     && isInteger(valueToCheck->getChild(0)->getOpCode(), cg)
     && isInteger(valueToCheck->getChild(1)->getOpCode(), cg)
     && performTransformation(comp, "O^O CODEGEN Optimizing ZEROCHK+%s %s\n", valueToCheck->getOpCode().getName(), valueToCheck->getName(cg->getDebug())))
      {
      if (valueToCheck->getOpCode().isCompareForOrder())
         {
         TR::TreeEvaluator::compareIntegersForOrder(valueToCheck, cg);
         }
      else
         {
         TR_ASSERT(valueToCheck->getOpCode().isCompareForEquality(), "Compare opcode must either be compare for order or for equality");
         TR::TreeEvaluator::compareIntegersForEquality(valueToCheck, cg);
         }
      generateLabelInstruction(branchOpCodeForCompare(valueToCheck->getOpCode(), true), node, slowPathLabel, cg);
      }
   else
      {
      TR::Register *value = cg->evaluate(node->getFirstChild());
      generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, value, value, cg);
      cg->decReferenceCount(node->getFirstChild());
      generateLabelInstruction(TR::InstOpCode::JE4, node, slowPathLabel, cg);
      }
   generateLabelInstruction(TR::InstOpCode::label, node, restartLabel,  cg);

   return NULL;
   }


bool isConditionCodeSetForCompare(TR::Node *node, bool *jumpOnOppositeCondition, TR::Compilation *comp)
   {
   // Disable.  Need to re-think how we handle overflow cases.
   //
   static char *disableNoCompareEFlags = feGetEnv("TR_disableNoCompareEFlags");
   if (disableNoCompareEFlags)
      return false;

   // See if there is a previous instruction that has set the condition flags
   // properly for this node's register
   //
   TR::Register *firstChildReg = node->getFirstChild()->getRegister();
   TR::Register *secondChildReg = node->getSecondChild()->getRegister();

   if (!firstChildReg || !secondChildReg)
      return false;

   // Find the last instruction that either
   //    1) sets the appropriate condition flags, or
   //    2) modifies the register to be tested
   // (and that hopefully does both)
   //
   TR::Instruction     *prevInstr;
   for (prevInstr = comp->cg()->getAppendInstruction();
        prevInstr;
        prevInstr = prevInstr->getPrev())
      {
      if (prevInstr->getOpCodeValue() == TR::InstOpCode::CMP4RegReg)
         {
         TR::Register *prevInstrTargetRegister = prevInstr->getTargetRegister();
         TR::Register *prevInstrSourceRegister = prevInstr->getSourceRegister();

         if (prevInstrTargetRegister && prevInstrSourceRegister &&
             (((prevInstrSourceRegister == firstChildReg) && (prevInstrTargetRegister == secondChildReg)) ||
              ((prevInstrSourceRegister == secondChildReg) && (prevInstrTargetRegister == firstChildReg))))
            {
            if (performTransformation(comp, "O^O SKIP BOUND CHECK COMPARISON at node %p\n", node))
               {
               if (prevInstrTargetRegister == secondChildReg)
                  *jumpOnOppositeCondition = true;
               return true;
               }
            else
               return false;
            }
         }

      if (prevInstr->getOpCodeValue() == TR::InstOpCode::label)
         {
         // This instruction is a possible branch target.
         return false;
         }

      if (prevInstr->getOpCode().modifiesSomeArithmeticFlags())
         {
         // This instruction overwrites the condition flags.
         return false;
         }
      }

   return false;
   }

void setImplicitNULLCHKExceptionInfo(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR_ASSERT_FATAL(node->hasFoldedImplicitNULLCHK(), "Attempt to set exception info on BNDCHK without implicit NULLCHK");

   TR::Compilation *comp = cg->comp();
   bool isTraceCG = comp->getOption(TR_TraceCG);

   TR::Instruction *faultingInstruction = cg->getImplicitExceptionPoint();
   if (faultingInstruction)
      {
      // Check and correctly set the implicit exception point
      //
      // The compare analyzer may have generated a secondary load to
      // resolved a compressed pointer and incorrectly set the exception point.
      // If that is the case, correctly set the exception point on
      // the comparison that actually throws the null pointer exception.
      //
      // The last instruction is a branch, the comparison is before.
      TR::Instruction *cmpInstruction = cg->getAppendInstruction()->getPrev();
      TR::InstOpCode::Mnemonic mnemonic = cmpInstruction->getOpCodeValue();
      bool isComparisonMemForm = mnemonic == TR::InstOpCode::CMP4MemReg ||
                                 mnemonic == TR::InstOpCode::CMP4RegMem;
      if (comp->useCompressedPointers() &&
          faultingInstruction != cmpInstruction &&
          isComparisonMemForm)
         {
         if (isTraceCG)
            traceMsg(comp,"Faulting instruction (previously %p) updated to %p\n",faultingInstruction,cmpInstruction);

         faultingInstruction = cmpInstruction;
         cg->setImplicitExceptionPoint(faultingInstruction);
         }

      faultingInstruction->setNeedsGCMap(0xFF00FFFF);
      faultingInstruction->setNode(node);
      }

   if (isTraceCG)
      traceMsg(comp,"Node %p has foldedimplicitNULLCHK, and a faulting instruction of %p\n",node,faultingInstruction);
   }

TR::Register *J9::X86::TreeEvaluator::BNDCHKEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR::Node *firstChild    = node->getFirstChild();
   TR::Node *secondChild   = node->getSecondChild();

   // Perform a bound check.
   //
   // Value propagation or profile-directed optimization may have determined
   // that the array bound is a constant, and lowered TR::arraylength into an
   // iconst. In this case, make sure that the constant is the second child.
   //
   TR::LabelSymbol *boundCheckFailureLabel = generateLabelSymbol(cg);
   TR::Instruction *instr;
   TR::Compilation *comp = cg->comp();

   bool skippedComparison = false;
   bool jumpOnOppositeCondition = false;
   if (firstChild->getOpCode().isLoadConst())
      {
      if (secondChild->getOpCode().isLoadConst() && firstChild->getInt() <= secondChild->getInt())
         {
         instr = generateLabelInstruction(TR::InstOpCode::JMP4, node, boundCheckFailureLabel, cg);
         cg->decReferenceCount(firstChild);
         cg->decReferenceCount(secondChild);
         }
      else
         {
         if (!isConditionCodeSetForCompare(node, &jumpOnOppositeCondition, cg->comp()))
            {
            node->swapChildren();
            TR::TreeEvaluator::compareIntegersForOrder(node, cg);
            node->swapChildren();
            instr = generateLabelInstruction(TR::InstOpCode::JAE4, node, boundCheckFailureLabel, cg);
            }
         else
            skippedComparison = true;
         }
      }
   else
      {
      if (!isConditionCodeSetForCompare(node, &jumpOnOppositeCondition, cg->comp()))
         {
         TR::TreeEvaluator::compareIntegersForOrder(node, cg);
         instr = generateLabelInstruction(TR::InstOpCode::JBE4, node, boundCheckFailureLabel, cg);
         }
      else
         skippedComparison = true;
      }

   if (skippedComparison)
      {
      if (jumpOnOppositeCondition)
         instr = generateLabelInstruction(TR::InstOpCode::JAE4, node, boundCheckFailureLabel, cg);
      else
         instr = generateLabelInstruction(TR::InstOpCode::JBE4, node, boundCheckFailureLabel, cg);

      cg->decReferenceCount(firstChild);
      cg->decReferenceCount(secondChild);
      }

   cg->addSnippet(new (cg->trHeapMemory()) TR::X86CheckFailureSnippet(cg, node->getSymbolReference(),
                                                     boundCheckFailureLabel,
                                                     instr,
                                                     false
                                                     ));
   if (node->hasFoldedImplicitNULLCHK())
      setImplicitNULLCHKExceptionInfo(node, cg);

   firstChild->setIsNonNegative(true);
   secondChild->setIsNonNegative(true);

   return NULL;
   }


TR::Register *J9::X86::TreeEvaluator::ArrayCopyBNDCHKEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // Check that first child >= second child
   //
   // If the first child is a constant and the second isn't, swap the children.
   //
   TR::Node        *firstChild             = node->getFirstChild();
   TR::Node        *secondChild            = node->getSecondChild();
   TR::LabelSymbol *boundCheckFailureLabel = generateLabelSymbol(cg);
   TR::Instruction *instr;

   if (firstChild->getOpCode().isLoadConst())
      {
      if (secondChild->getOpCode().isLoadConst())
         {
         if (firstChild->getInt() < secondChild->getInt())
            {
            // Check will always fail, just jump to failure snippet
            //
            instr = generateLabelInstruction(TR::InstOpCode::JMP4, node, boundCheckFailureLabel, cg);
            }
         else
            {
            // Check will always succeed, no need for an instruction
            //
            instr = NULL;
            }
         cg->decReferenceCount(firstChild);
         cg->decReferenceCount(secondChild);
         }
      else
         {
         node->swapChildren();
         TR::TreeEvaluator::compareIntegersForOrder(node, cg);
         node->swapChildren();
         instr = generateLabelInstruction(TR::InstOpCode::JG4, node, boundCheckFailureLabel, cg);
         }
      }
   else
      {
      TR::TreeEvaluator::compareIntegersForOrder(node, cg);
      instr = generateLabelInstruction(TR::InstOpCode::JL4, node, boundCheckFailureLabel, cg);
      }

   if (instr)
      cg->addSnippet(new (cg->trHeapMemory()) TR::X86CheckFailureSnippet(cg, node->getSymbolReference(),
                                                             boundCheckFailureLabel,
                                                             instr,
                                                             false
                                                             ));

   return NULL;
   }


TR::Register *J9::X86::TreeEvaluator::ArrayStoreCHKEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(comp->fe());
   TR::Instruction *prevInstr = cg->getAppendInstruction();
   TR::LabelSymbol *startLabel,
                  *startOfWrtbarLabel,
                  *doNullStoreLabel,
                  *doneLabel;

   // skipStoreNullCheck
   // skipJLOCheck
   // skipSuperClassCheck
   // cannotSkipWriteBarrier

   flags16_t actions;

   TR::Node *firstChild = node->getFirstChild();
   TR::Node *sourceChild = firstChild->getSecondChild();

   static bool isRealTimeGC = comp->getOptions()->realTimeGC();
   auto gcMode = TR::Compiler->om.writeBarrierType();

   bool isNonRTWriteBarrierRequired = (gcMode != gc_modron_wrtbar_none && !firstChild->skipWrtBar()) ? true : false;
   bool generateWriteBarrier = isRealTimeGC || isNonRTWriteBarrierRequired;
   bool nopASC = (node->getArrayStoreClassInNode() &&
                  comp->performVirtualGuardNOPing() &&
                  !fej9->classHasBeenExtended(node->getArrayStoreClassInNode())
                 ) ?  true : false;

   // OffHeap runs defer destination evaluation after GC point.
   static char *disableDeferDestinationEvaluation = feGetEnv("TR_DisableDeferDestinationEvaluation");
   bool deferDestinationEvaluation = TR::Compiler->om.isOffHeapAllocationEnabled() && !disableDeferDestinationEvaluation;

   doneLabel = generateLabelSymbol(cg);
   doneLabel->setEndInternalControlFlow();

   if(generateWriteBarrier)
      {
      startOfWrtbarLabel = generateLabelSymbol(cg);
      // For OffHeap we use mainline store for null stores to consolidate store paths and defer
      // destination evaluation. OffHeap will perform redundant wrtbar on null stores.
      doNullStoreLabel = deferDestinationEvaluation ? startOfWrtbarLabel : generateLabelSymbol(cg);
      }
   else
      {
      startOfWrtbarLabel = doneLabel;
      doNullStoreLabel = doneLabel;
      }

   bool usingCompressedPointers = false;
   bool usingLowMemHeap  = false;
   bool useShiftedOffsets = (TR::Compiler->om.compressedReferenceShiftOffset() != 0);

   if (comp->useCompressedPointers() && firstChild->getOpCode().isIndirect())
      {
      usingLowMemHeap = true;
      usingCompressedPointers = true;

      if (useShiftedOffsets)
         {
         while ((sourceChild->getNumChildren() > 0) && (sourceChild->getOpCodeValue() != TR::a2l))
            sourceChild = sourceChild->getFirstChild();
         if (sourceChild->getOpCodeValue() == TR::a2l)
            sourceChild = sourceChild->getFirstChild();
         // this is required so that different registers are
         // allocated for the actual store and translated values
         sourceChild->incReferenceCount();
         }
      }

   // -------------------------------------------------------------------------
   //
   // Evaluate all of the children here to avoid issues with internal control
   // flow and outlined instructions.
   //
   // -------------------------------------------------------------------------

   TR::MemoryReference *tempMR = NULL;
   TR::Node *dstArrayNode, *offsetNode = NULL;

   if (generateWriteBarrier)
      {
      if (!deferDestinationEvaluation)
         {
         tempMR = generateX86MemoryReference(firstChild, cg);
         }
      else
         {
         /* Evaluate destination subtrees
         * ArrayStoreCHK
         *    awrtbari  // firstChild
         *      aloadi  <contiguousArrayDataAddrField>
         *        aload     // dstArrayNode
         *      ...
         * OR
         * ArrayStoreCHK
         *    awrtbari  // firstChild
         *      aladd (internalPtr )
         *        aloadi  <contiguousArrayDataAddrField>
         *          aload     // dstArrayNode
         *        <offset>  // offsetNode
         *      ...
         */
         if (firstChild->getFirstChild()->isDataAddrPointer())
            dstArrayNode = firstChild->getFirstChild()->getFirstChild();
         else if (firstChild->getFirstChild()->getOpCodeValue() == TR::aladd && firstChild->getFirstChild()->getFirstChild()->isDataAddrPointer())
            {
            dstArrayNode = firstChild->getFirstChild()->getFirstChild()->getFirstChild();
            offsetNode = firstChild->getFirstChild()->getSecondChild();
            }
         else
            {
            TR_ASSERT_FATAL(false, "Unexpected array access tree shape for OffHeap in ArrayStoreCHKEvaluator");
            }

         cg->evaluate(dstArrayNode);
         if (offsetNode &&
               !(offsetNode->getOpCode().isLoadConst() &&
               offsetNode->getLongInt() >= TR::getMinSigned<TR::Int32>() &&
               offsetNode->getLongInt() <= TR::getMaxSigned<TR::Int32>()))
            cg->evaluate(offsetNode);
         }
      }

   TR::Node *destinationChild = firstChild->getChild(2);
   TR::Register *destinationRegister = cg->evaluate(destinationChild);
   TR::Register *sourceRegister = cg->evaluate(sourceChild);

   TR_X86ScratchRegisterManager *scratchRegisterManager =
      cg->generateScratchRegisterManager(comp->target().is64Bit() ? 15 : 7);

   TR::Register *compressedRegister = NULL;
   if (usingCompressedPointers)
      {
      if (usingLowMemHeap && !useShiftedOffsets)
         compressedRegister = sourceRegister;
      else
         {
         // valid for useShiftedOffsets
         compressedRegister = cg->evaluate(firstChild->getSecondChild());
         if (!usingLowMemHeap)
            {
            generateRegRegInstruction(TR::InstOpCode::TESTRegReg(), firstChild, sourceRegister, sourceRegister, cg);
            generateRegRegInstruction(TR::InstOpCode::CMOVERegReg(), firstChild, compressedRegister, sourceRegister, cg);
            }
         }
      }

   // -------------------------------------------------------------------------
   //
   // If the source reference is NULL, the array store checks and the write
   // barrier can be bypassed.  Generate the NULL store in an outlined sequence.
   // For realtime GC we must still do the barrier.  If we are not generating
   // a write barrier then the store will happen inline.
   //
   // -------------------------------------------------------------------------

   startLabel = generateLabelSymbol(cg);
   startLabel->setStartInternalControlFlow();
   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

   generateRegRegInstruction(TR::InstOpCode::TESTRegReg(), node, sourceRegister, sourceRegister, cg);

   TR::LabelSymbol *nullTargetLabel =
      isRealTimeGC ? startOfWrtbarLabel : doNullStoreLabel;

   generateLabelInstruction(TR::InstOpCode::JE4, node, nullTargetLabel, cg);

   // -------------------------------------------------------------------------
   //
   // Generate up-front array store checks to avoid calling out to the helper.
   //
   // -------------------------------------------------------------------------

   TR::LabelSymbol *postASCLabel = NULL;
   if (nopASC)
      {
      // Speculatively NOP the array store check if VP is able to prove that the ASC
      // would always succeed given the current state of the class hierarchy.
      //
      TR::Node *helperCallNode = TR::Node::createWithSymRef(TR::call, 2, 2, sourceChild, destinationChild, node->getSymbolReference());
      helperCallNode->copyByteCodeInfo(node);

      TR::LabelSymbol *oolASCLabel = generateLabelSymbol(cg);
      TR::LabelSymbol *restartLabel;

      if (generateWriteBarrier)
         {
         restartLabel = startOfWrtbarLabel;
         }
      else
         {
         restartLabel = postASCLabel = generateLabelSymbol(cg);
         }

      TR_OutlinedInstructions *outlinedASCHelperCall =
         new (cg->trHeapMemory()) TR_OutlinedInstructions(helperCallNode, TR::call, NULL, oolASCLabel, restartLabel, cg);
      cg->getOutlinedInstructionsList().push_front(outlinedASCHelperCall);

      static char *alwaysDoOOLASCc = feGetEnv("TR_doOOLASC");
      static bool alwaysDoOOLASC = alwaysDoOOLASCc ? true : false;

      if (!alwaysDoOOLASC)
         {
         TR_VirtualGuard *virtualGuard = TR_VirtualGuard::createArrayStoreCheckGuard(comp, node, node->getArrayStoreClassInNode());
         TR::Instruction *pachable = generateVirtualGuardNOPInstruction(node, virtualGuard->addNOPSite(), NULL, oolASCLabel, cg);
         }
      else
         {
         generateLabelInstruction(TR::InstOpCode::JMP4, node, oolASCLabel, cg);
         }

      // Restore the reference counts of the children created for the temporary vacll node above.
      //
      sourceChild->decReferenceCount();
      destinationChild->decReferenceCount();
      }
   else
      {
      TR::TreeEvaluator::VMarrayStoreCHKEvaluator(
         node,
         sourceChild,
         destinationChild,
         scratchRegisterManager,
         startOfWrtbarLabel,
         prevInstr,
         cg);
      }

   // -------------------------------------------------------------------------
   //
   // Generate write barrier.
   //
   // -------------------------------------------------------------------------

   bool isSourceNonNull = sourceChild->isNonNull();

   if (generateWriteBarrier)
      {
      generateLabelInstruction(TR::InstOpCode::label, node, startOfWrtbarLabel, cg);

      if (!isRealTimeGC)
         {
         // HACK: set the nullness property on the source so that the write barrier
         //       doesn't do the same test.
         //
         sourceChild->setIsNonNull(true);
         }

      if (deferDestinationEvaluation)
         {
         // Perform deferred destination evaluation
         tempMR = generateX86MemoryReference(firstChild, cg);
         }

      TR::TreeEvaluator::VMwrtbarWithStoreEvaluator(
         node,
         tempMR,
         scratchRegisterManager,
         destinationChild,
         sourceChild,
         true,
         cg,
         true);
      }
   else if (postASCLabel)
      {
      // Lay down a arestart label for OOL ASC if the write barrier was skipped
      //
      generateLabelInstruction(TR::InstOpCode::label, node, postASCLabel, cg);
      }

   // -------------------------------------------------------------------------
   //
   // Either do the bypassed NULL store out of line or the reference store
   // inline if the write barrier was omitted.
   //
   // -------------------------------------------------------------------------

   TR::MemoryReference *tempMR2 = NULL;

   TR::Instruction *dependencyAnchorInstruction = NULL;

   if (!isRealTimeGC)
      {
      // OffHeap uses the already generated mainline VMwrtbarWithStoreEvaluator for null stores
      if (generateWriteBarrier && !deferDestinationEvaluation)
         {
         assert(isNonRTWriteBarrierRequired);
         assert(tempMR);

         // HACK: reset the nullness property on the source.
         //
         sourceChild->setIsNonNull(isSourceNonNull);

         // Perform the NULL store that was bypassed earlier by the write barrier.
         //
         TR_OutlinedInstructionsGenerator og(nullTargetLabel, node, cg);

         tempMR2 = generateX86MemoryReference(*tempMR, 0, cg);

         if (usingCompressedPointers)
            generateMemRegInstruction(TR::InstOpCode::S4MemReg, node, tempMR2, compressedRegister, cg);
         else
            generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, tempMR2, sourceRegister, cg);

         generateLabelInstruction(TR::InstOpCode::JMP4, node, doneLabel, cg);
         og.endOutlinedInstructionSequence();
         }
      else if (!generateWriteBarrier)
         {
         // No write barrier emitted.  Evaluate the store here.
         //
         assert(!isNonRTWriteBarrierRequired);
         assert(doneLabel == nullTargetLabel);

         // This is where the dependency condition will eventually go.
         //
         dependencyAnchorInstruction = cg->getAppendInstruction();

         tempMR = generateX86MemoryReference(firstChild, cg);

         TR::X86MemRegInstruction *storeInstr;

         if (usingCompressedPointers)
            storeInstr = generateMemRegInstruction(TR::InstOpCode::S4MemReg, node, tempMR, compressedRegister, cg);
         else
            storeInstr = generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, tempMR, sourceRegister, cg);

         cg->setImplicitExceptionPoint(storeInstr);

         if (!usingLowMemHeap || useShiftedOffsets)
            cg->decReferenceCount(sourceChild);
         cg->decReferenceCount(destinationChild);
         tempMR->decNodeReferenceCounts(cg);
         }
      }

   // -------------------------------------------------------------------------
   //
   // Generate outermost register dependencies
   //
   // -------------------------------------------------------------------------

   TR::RegisterDependencyConditions *deps = generateRegisterDependencyConditions(13, 13, cg);
   deps->unionPostCondition(destinationRegister, TR::RealRegister::NoReg, cg);
   deps->unionPostCondition(sourceRegister, TR::RealRegister::NoReg, cg);

   scratchRegisterManager->addScratchRegistersToDependencyList(deps);

   if (usingCompressedPointers && (!usingLowMemHeap || useShiftedOffsets))
      {
      deps->unionPostCondition(compressedRegister, TR::RealRegister::NoReg, cg);
      }

   if (generateWriteBarrier)
      {
      // Memory reference is not live in an internal control flow region.
      //
      if (tempMR->getBaseRegister() && tempMR->getBaseRegister() != destinationRegister)
         {
         deps->unionPostCondition(tempMR->getBaseRegister(), TR::RealRegister::NoReg, cg);
         }

      if (tempMR->getIndexRegister() && tempMR->getIndexRegister() != destinationRegister)
         {
         deps->unionPostCondition(tempMR->getIndexRegister(), TR::RealRegister::NoReg, cg);
         }

      if (deferDestinationEvaluation && dstArrayNode->getRegister() != destinationRegister)
         {
         // For OffHeap tempMR->getBaseRegister() would be the dataAddrPtr not the baseArray.
         deps->unionPostCondition(dstArrayNode->getRegister(), TR::RealRegister::NoReg, cg);
         }

      if (comp->target().is64Bit())
         {
         TR::Register *addressRegister =tempMR->getAddressRegister();
         if (addressRegister && addressRegister != destinationRegister)
            {
            deps->unionPostCondition(addressRegister, TR::RealRegister::NoReg, cg);
            }
         }
      }

   if (tempMR2 && comp->target().is64Bit())
      {
      TR::Register *addressRegister = tempMR2->getAddressRegister();
      if (addressRegister && addressRegister != destinationRegister)
         deps->unionPostCondition(addressRegister, TR::RealRegister::NoReg, cg);
      }

   deps->unionPostCondition(
      cg->getVMThreadRegister(),
      (TR::RealRegister::RegNum)cg->getVMThreadRegister()->getAssociation(), cg);

   deps->stopAddingConditions();

   scratchRegisterManager->stopUsingRegisters();

   if (dependencyAnchorInstruction)
      {
      generateLabelInstruction(dependencyAnchorInstruction, TR::InstOpCode::label, doneLabel, deps, cg);
      }
   else
      {
      generateLabelInstruction(TR::InstOpCode::label, node, doneLabel, deps, cg);
      }

   if (usingCompressedPointers)
      {
      cg->decReferenceCount(firstChild->getSecondChild());
      cg->decReferenceCount(firstChild);
      }

   if (comp->useAnchors() && firstChild->getOpCode().isIndirect())
      firstChild->setStoreAlreadyEvaluated(true);

   return NULL;
   }

TR::Register *J9::X86::TreeEvaluator::ArrayCHKEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   return TR::TreeEvaluator::VMarrayCheckEvaluator(node, cg);
   }


// Handles both BNDCHKwithSpineCHK and SpineCHK nodes.
//
TR::Register *J9::X86::TreeEvaluator::BNDCHKwithSpineCHKEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());
   bool needsBoundCheck = (node->getOpCodeValue() == TR::BNDCHKwithSpineCHK) ? true : false;

   TR::Node *loadOrStoreChild = node->getFirstChild();
   TR::Node *baseArrayChild = node->getSecondChild();
   TR::Node *arrayLengthChild;
   TR::Node *indexChild;

   if (needsBoundCheck)
      {
      arrayLengthChild = node->getChild(2);
      indexChild = node->getChild(3);
      }
   else
      {
      arrayLengthChild = NULL;
      indexChild = node->getChild(2);
      }

   // Perform a bound check.
   //
   // Value propagation or profile-directed optimization may have determined
   // that the array bound is a constant, and lowered TR::arraylength into an
   // iconst.  In this case, make sure that the constant is the second child.
   //
   TR::InstOpCode::Mnemonic branchOpCode;

   // For primitive stores anchored under the check node, we must evaluate the source node
   // before the bound check branch so that its available to the snippet.  We can make
   // an exception for constant values that could be folded directly into a immediate
   // store instruction.
   //
   if (loadOrStoreChild->getOpCode().isStore() && loadOrStoreChild->getReferenceCount() <= 1)
      {
      TR::Node *valueChild = loadOrStoreChild->getSecondChild();

      if (!valueChild->getOpCode().isLoadConst() ||
          (valueChild->getOpCode().isLoadConst() &&
          ((valueChild->getDataType() == TR::Float) || (valueChild->getDataType() == TR::Double) ||
           (comp->target().is64Bit() && !IS_32BIT_SIGNED(valueChild->getLongInt())))))
         {
         cg->evaluate(valueChild);
         }
      }

   TR::Register *baseArrayReg = cg->evaluate(baseArrayChild);

   TR::TreeEvaluator::preEvaluateEscapingNodesForSpineCheck(node, cg);

   TR::Instruction *faultingInstruction = NULL;

   TR::LabelSymbol *boundCheckFailureLabel = generateLabelSymbol(cg);
   TR::X86LabelInstruction *checkInstr = NULL;

   if (needsBoundCheck)
      {
      if (arrayLengthChild->getOpCode().isLoadConst())
         {
         if (indexChild->getOpCode().isLoadConst() && arrayLengthChild->getInt() <= indexChild->getInt())
            {
            // Create real check failure snippet if we can prove the
            // bound check will always fail.
            //
            branchOpCode = TR::InstOpCode::JMP4;
            cg->decReferenceCount(arrayLengthChild);
            cg->decReferenceCount(indexChild);
            }
         else
            {
            TR::DataType dt = loadOrStoreChild->getDataType();
            int32_t elementSize = (dt == TR::Address) ?  TR::Compiler->om.sizeofReferenceField()
                                                      : TR::Symbol::convertTypeToSize(dt);

            if (TR::Compiler->om.isDiscontiguousArray(arrayLengthChild->getInt(), elementSize))
               {
               // Create real check failure snippet if we can prove the spine check
               // will always fail
               //
               branchOpCode = TR::InstOpCode::JMP4;
               cg->decReferenceCount(arrayLengthChild);
               if (!indexChild->getOpCode().isLoadConst())
                  {
                  cg->evaluate(indexChild);
                  }

               cg->decReferenceCount(indexChild);

               faultingInstruction = cg->getImplicitExceptionPoint();
               }
            else
               {
               // Check the bounds.
               //
               TR::TreeEvaluator::compareIntegersForOrder(node, indexChild, arrayLengthChild, cg);
               branchOpCode = TR::InstOpCode::JAE4;
               faultingInstruction = cg->getImplicitExceptionPoint();
               }
            }
         }
      else
         {
         // Check the bounds.
         //
         TR::TreeEvaluator::compareIntegersForOrder(node, arrayLengthChild, indexChild, cg);
         branchOpCode = TR::InstOpCode::JBE4;
         faultingInstruction = cg->getImplicitExceptionPoint();
         }

      static char *forceArraylet = feGetEnv("TR_forceArraylet");
      if (forceArraylet)
         {
         branchOpCode = TR::InstOpCode::JMP4;
         }

      checkInstr = generateLabelInstruction(branchOpCode, node, boundCheckFailureLabel, cg);
      }
   else
      {
      // -------------------------------------------------------------------------
      // Check if the base array has a spine.  If so, process out of line.
      // -------------------------------------------------------------------------

      if (!indexChild->getOpCode().isLoadConst())
         {
         cg->evaluate(indexChild);
         }

      TR::MemoryReference *arraySizeMR =
         generateX86MemoryReference(baseArrayReg, fej9->getOffsetOfContiguousArraySizeField(), cg);

      generateMemImmInstruction(TR::InstOpCode::CMP4MemImms, node, arraySizeMR, 0, cg);
      generateLabelInstruction(TR::InstOpCode::JE4, node, boundCheckFailureLabel, cg);
      }

   // -----------------------------------------------------------------------------------
   // Track all virtual register use within the mainline path.  This info will be used
   // to adjust the virtual register use counts within the outlined path for more precise
   // register assignment.
   // -----------------------------------------------------------------------------------

   cg->startRecordingRegisterUsage();

   TR::Register *loadOrStoreReg = NULL;
   TR::Register *valueReg = NULL;

   int32_t indexValue;

   // For reference stores, only evaluate the array element address because the store cannot
   // happen here (it must be done via the array store check).
   //
   // For primitive stores, evaluate them now.
   //
   // For loads, evaluate them now.
   //
   if (loadOrStoreChild->getOpCode().isStore())
      {
      if (loadOrStoreChild->getReferenceCount() > 1)
         {
         TR_ASSERT(loadOrStoreChild->getOpCode().isWrtBar(), "Opcode must be wrtbar");
         loadOrStoreReg = cg->evaluate(loadOrStoreChild->getFirstChild());
         cg->decReferenceCount(loadOrStoreChild->getFirstChild());
         }
      else
         {
         // If the store is not commoned then it must be a primitive store.
         //
         loadOrStoreReg = cg->evaluate(loadOrStoreChild);
         valueReg = loadOrStoreChild->getSecondChild()->getRegister();

         if (!valueReg)
            {
            // If the immediate value was not evaluated then it must have been folded
            // into the instruction.
            //
            TR_ASSERT(loadOrStoreChild->getSecondChild()->getOpCode().isLoadConst(), "unevaluated, non-constant value child");
            TR_ASSERT(IS_32BIT_SIGNED(loadOrStoreChild->getSecondChild()->getInt()), "immediate value too wide for instruction");
            }
         }
      }
   else
      {
      loadOrStoreReg = cg->evaluate(loadOrStoreChild);
      }

   // -----------------------------------------------------------------------------------
   // Stop tracking virtual register usage.
   // -----------------------------------------------------------------------------------

   TR::list<OMR::RegisterUsage*> *mainlineRUL = cg->stopRecordingRegisterUsage();

   TR::Register *indexReg = indexChild->getRegister();

   // Index register must be in a register or a constant.
   //
   TR_ASSERT((indexReg || indexChild->getOpCode().isLoadConst()),
      "index child is not evaluated or constant: indexReg=%p, indexChild=%p", indexReg, indexChild);

   if (indexReg)
      {
      indexValue = -1;
      }
   else
      {
      indexValue = indexChild->getInt();
      }

   // TODO: don't always require the VM thread
   //
   TR::RegisterDependencyConditions *deps =
      generateRegisterDependencyConditions((uint8_t) 0, 1, cg);

   deps->addPostCondition(
      cg->getVMThreadRegister(),
      (TR::RealRegister::RegNum)cg->getVMThreadRegister()->getAssociation(), cg);

   deps->stopAddingConditions();

   TR::LabelSymbol *mergeLabel = generateLabelSymbol(cg);
   mergeLabel->setInternalControlFlowMerge();
   TR::X86LabelInstruction *restartInstr = generateLabelInstruction(TR::InstOpCode::label, node, mergeLabel, deps, cg);

   TR_OutlinedInstructions *arrayletOI =
      generateArrayletReference(
         node,
         loadOrStoreChild,
         checkInstr,
         boundCheckFailureLabel,
         mergeLabel,
         baseArrayReg,
         loadOrStoreReg,
         indexReg,
         indexValue,
         valueReg,
         needsBoundCheck,
         cg);

   arrayletOI->setMainlinePathRegisterUsageList(mainlineRUL);

   if (node->hasFoldedImplicitNULLCHK())
      {
      if (faultingInstruction)
         {
         faultingInstruction->setNeedsGCMap(0xFF00FFFF);
         faultingInstruction->setNode(node);
         }
      }

   if (arrayLengthChild)
      arrayLengthChild->setIsNonNegative(true);

   indexChild->setIsNonNegative(true);

   cg->decReferenceCount(loadOrStoreChild);
   cg->decReferenceCount(baseArrayChild);

   if (!needsBoundCheck)
      {
      // Spine checks must decrement the reference count on the index explicitly.
      //
      cg->decReferenceCount(indexChild);
      }

   return NULL;

   }

/*
 * this evaluator is used specifically for evaluate the following three nodes
 *
 *  storFence
 *  loadFence
 *  storeFence
 *
 * Since Java specification for loadfence and storefenc is stronger
 * than the intel specification, a full mfence instruction have to
 * be used for all three of them
 *
 * Due to performance penalty of mfence, a faster lockor on RSP is used
 * it achieve the same functionality but runs faster.
 */
TR::Register *J9::X86::TreeEvaluator::barrierFenceEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR::ILOpCodes opCode = node->getOpCodeValue();
   if (opCode == TR::fullFence && node->canOmitSync())
      {
      generateLabelInstruction(TR::InstOpCode::label, node, generateLabelSymbol(cg), cg);
      }
   else if(cg->comp()->getOption(TR_X86UseMFENCE))
      {
      generateInstruction(TR::InstOpCode::MFENCE, node, cg);
      }
   else
      {
      TR::RealRegister *stackReg = cg->machine()->getRealRegister(TR::RealRegister::esp);
      TR::MemoryReference *mr = generateX86MemoryReference(stackReg, intptr_t(0), cg);

      mr->setRequiresLockPrefix();
      generateMemImmInstruction(TR::InstOpCode::OR4MemImms, node, mr, 0, cg);
      cg->stopUsingRegister(stackReg);
      }
   return NULL;
   }


TR::Register *J9::X86::TreeEvaluator::readbarEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR_ASSERT(node->getNumChildren() == 1, "readbar node should have one child");
   TR::Node *handleNode = node->getChild(0);

   TR::Compilation *comp = cg->comp();

   bool needBranchAroundForNULL = !node->hasFoldedImplicitNULLCHK() && !node->isNonNull();
   traceMsg(comp, "\nnode %p has folded implicit nullchk: %d\n", node, node->hasFoldedImplicitNULLCHK());
   traceMsg(comp, "node %p is nonnull: %d\n", node, node->isNonNull());
   traceMsg(comp, "node %p needs branchAround: %d\n", node, needBranchAroundForNULL);

   TR::LabelSymbol *startLabel=NULL;
   TR::LabelSymbol *doneLabel=NULL;
   if (needBranchAroundForNULL)
      {
      startLabel = generateLabelSymbol(cg);
      doneLabel  = generateLabelSymbol(cg);

      generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);
      startLabel->setStartInternalControlFlow();
      }

   TR::Register *handleRegister = cg->intClobberEvaluate(handleNode);

   if (needBranchAroundForNULL)
      {
      // if handle is NULL, then just branch around the redirection
      generateRegRegInstruction(TR::InstOpCode::TESTRegReg(), node, handleRegister, handleRegister, cg);
      generateLabelInstruction(TR::InstOpCode::JE4, handleNode, doneLabel, cg);
      }

   // handle is not NULL or we're an implicit nullcheck, so go through forwarding pointer to get object
   TR::MemoryReference *handleMR = generateX86MemoryReference(handleRegister, node->getSymbolReference()->getOffset(), cg);
   TR::Instruction *forwardingInstr=generateRegMemInstruction(TR::InstOpCode::L4RegMem, handleNode, handleRegister, handleMR, cg);
   cg->setImplicitExceptionPoint(forwardingInstr);

   if (needBranchAroundForNULL)
      {
      TR::RegisterDependencyConditions *deps = generateRegisterDependencyConditions((uint8_t) 0, 1, cg);
      deps->addPostCondition(handleRegister, TR::RealRegister::NoReg, cg);

      // and we're done
      generateLabelInstruction(TR::InstOpCode::label, node, doneLabel, deps, cg);

      doneLabel->setEndInternalControlFlow();
      }

   node->setRegister(handleRegister);
   cg->decReferenceCount(handleNode);

   return handleRegister;
   }

static
TR::Register * highestOneBit(TR::Node *node, TR::CodeGenerator *cg, TR::Register *reg, bool is64Bit)
   {
   // xor r1, r1
   // bsr r2, reg
   // setne r1
   // shl r1, r2
   TR::Register *scratchReg = cg->allocateRegister();
   TR::Register *bsrReg = cg->allocateRegister();
   generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, scratchReg, scratchReg, cg);
   generateRegRegInstruction(TR::InstOpCode::BSRRegReg(is64Bit), node, bsrReg, reg, cg);
   generateRegInstruction(TR::InstOpCode::SETNE1Reg, node, scratchReg, cg);
   TR::RegisterDependencyConditions  *shiftDependencies = generateRegisterDependencyConditions((uint8_t)1, 1, cg);
   shiftDependencies->addPreCondition(bsrReg, TR::RealRegister::ecx, cg);
   shiftDependencies->addPostCondition(bsrReg, TR::RealRegister::ecx, cg);
   shiftDependencies->stopAddingConditions();
   generateRegRegInstruction(TR::InstOpCode::SHLRegCL(is64Bit), node, scratchReg, bsrReg, shiftDependencies, cg);
   cg->stopUsingRegister(bsrReg);
   return scratchReg;
   }

TR::Register *J9::X86::TreeEvaluator::integerHighestOneBit(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR_ASSERT(node->getNumChildren() == 1, "Node has a wrong number of children (i.e. !=1 )! ");
   TR::Node *child = node->getFirstChild();
   TR::Register *inputReg = cg->evaluate(child);
   TR::Register *resultReg = highestOneBit(node, cg, inputReg, cg->comp()->target().is64Bit());
   cg->decReferenceCount(child);
   node->setRegister(resultReg);
   return resultReg;
   }

TR::Register *J9::X86::TreeEvaluator::longHighestOneBit(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR_ASSERT(node->getNumChildren() == 1, "Node has a wrong number of children (i.e. !=1 )! ");
   TR::Node *child = node->getFirstChild();
   TR::Register *inputReg = cg->evaluate(child);
   TR::Register *resultReg = NULL;
   if (cg->comp()->target().is64Bit())
      {
      resultReg = highestOneBit(node, cg, inputReg, true);
      }
   else
      {
      //mask out low part result if high part is not 0
      //xor r1 r1
      //cmp inputHigh, 0
      //setne r1
      //dec r1
      //and resultLow, r1
      //ret resultHigh:resultLow
      TR::Register *inputLow = inputReg->getLowOrder();
      TR::Register *inputHigh = inputReg->getHighOrder();
      TR::Register *maskReg = cg->allocateRegister();
      TR::Register *resultHigh = highestOneBit(node, cg, inputHigh, false);
      TR::Register *resultLow = highestOneBit(node, cg, inputLow, false);
      generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, maskReg, maskReg, cg);
      generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, inputHigh, 0, cg);
      generateRegInstruction(TR::InstOpCode::SETNE1Reg, node, maskReg, cg);
      generateRegInstruction(TR::InstOpCode::DEC4Reg, node, maskReg, cg);
      generateRegRegInstruction(TR::InstOpCode::AND4RegReg, node, resultLow, maskReg, cg);
      resultReg = cg->allocateRegisterPair(resultLow, resultHigh);
      cg->stopUsingRegister(maskReg);
      }
   cg->decReferenceCount(child);
   node->setRegister(resultReg);
   return resultReg;
   }

static
TR::Register *lowestOneBit(TR::Node *node, TR::CodeGenerator *cg, TR::Register *reg, bool is64Bit)
   {
   TR::Register *resultReg = cg->allocateRegister();
   generateRegRegInstruction(TR::InstOpCode::MOVRegReg(is64Bit), node, resultReg, reg, cg);
   generateRegInstruction(TR::InstOpCode::NEGReg(is64Bit), node, resultReg, cg);
   generateRegRegInstruction(TR::InstOpCode::ANDRegReg(is64Bit), node, resultReg, reg, cg);
   return resultReg;
   }

TR::Register *J9::X86::TreeEvaluator::integerLowestOneBit(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR_ASSERT(node->getNumChildren() == 1, "Node has a wrong number of children (i.e. !=1 )! ");
   TR::Node *child = node->getFirstChild();
   TR::Register *inputReg = cg->evaluate(child);
   TR::Register *reg = lowestOneBit(node, cg, inputReg, cg->comp()->target().is64Bit());
   node->setRegister(reg);
   cg->decReferenceCount(child);
   return reg;
   }

TR::Register *J9::X86::TreeEvaluator::longLowestOneBit(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR_ASSERT(node->getNumChildren() == 1, "Node has a wrong number of children (i.e. !=1 )! ");
   TR::Node *child = node->getFirstChild();
   TR::Register *inputReg = cg->evaluate(child);
   TR::Register *resultReg = NULL;
   if (cg->comp()->target().is64Bit())
      {
      resultReg = lowestOneBit(node, cg, inputReg, true);
      }
   else
      {
      // mask out high part if low part is not 0
      // xor r1, r1
      // get low result
      // setne r1
      // dec   r1
      // and   r1, inputHigh
      // get high result
      // return resultHigh:resultLow
      TR::Register *inputHigh = inputReg->getHighOrder();
      TR::Register *inputLow = inputReg->getLowOrder();
      TR::Register *scratchReg = cg->allocateRegister();
      generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, scratchReg, scratchReg, cg);
      TR::Register *resultLow = lowestOneBit(node, cg, inputLow, false);
      generateRegInstruction(TR::InstOpCode::SETNE1Reg, node, scratchReg, cg);
      generateRegInstruction(TR::InstOpCode::DEC4Reg, node, scratchReg, cg);
      generateRegRegInstruction(TR::InstOpCode::AND4RegReg, node, scratchReg, inputHigh, cg);
      TR::Register *resultHigh = lowestOneBit(node, cg, scratchReg, false);
      cg->stopUsingRegister(scratchReg);
      resultReg = cg->allocateRegisterPair(resultLow, resultHigh);
      }
   node->setRegister(resultReg);
   cg->decReferenceCount(child);
   return resultReg;
   }


static
TR::Register *numberOfLeadingZeros(TR::Node *node, TR::CodeGenerator *cg, TR::Register *reg, bool is64Bit, bool isLong)
   {
   // xor r1, r1
   // bsr r2, reg
   // sete r1
   // dec r1
   // inc r2
   // and r2, r1
   // mov r1, is64Bit? 64: 32
   // sub r1, r2
   // ret r1
   TR::Register *maskReg = cg->allocateRegister();
   TR::Register *bsrReg = cg->allocateRegister();
   generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, maskReg, maskReg, cg);
   generateRegRegInstruction(TR::InstOpCode::BSRRegReg(is64Bit), node, bsrReg, reg, cg);
   generateRegInstruction(TR::InstOpCode::SETE1Reg, node, maskReg, cg);
   generateRegInstruction(TR::InstOpCode::DECReg(is64Bit), node, maskReg, cg);
   generateRegInstruction(TR::InstOpCode::INCReg(is64Bit), node, bsrReg, cg);
   generateRegRegInstruction(TR::InstOpCode::ANDRegReg(is64Bit), node, bsrReg, maskReg, cg);
   generateRegImmInstruction(TR::InstOpCode::MOVRegImm4(is64Bit), node, maskReg, isLong ? 64 : 32, cg);
   generateRegRegInstruction(TR::InstOpCode::SUBRegReg(is64Bit), node, maskReg, bsrReg, cg);
   cg->stopUsingRegister(bsrReg);
   return maskReg;
   }

TR::Register *J9::X86::TreeEvaluator::integerNumberOfLeadingZeros(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR_ASSERT(node->getNumChildren() == 1, "Node has a wrong number of children (i.e. !=1 )! ");
   TR::Node* child = node->getFirstChild();
   TR::Register* inputReg = cg->evaluate(child);
   TR::Register* resultReg = numberOfLeadingZeros(node, cg, inputReg, false, false);
   node->setRegister(resultReg);
   cg->decReferenceCount(child);
   return resultReg;
   }

TR::Register *J9::X86::TreeEvaluator::longNumberOfLeadingZeros(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR_ASSERT(node->getNumChildren() == 1, "Node has a wrong number of children (i.e. !=1 )! ");
   TR::Node* child = node->getFirstChild();
   TR::Register* inputReg = cg->evaluate(child);
   TR::Register *resultReg = NULL;
   if (cg->comp()->target().is64Bit())
      {
      resultReg = numberOfLeadingZeros(node, cg, inputReg, true, true);
      }
   else
      {
      // keep low part if high part is 0
      // xor r1, r1
      // cmp inputHigh, 0
      // setne r1
      // dec r1
      // and resultLow, r1
      // add resultHigh, resultLow
      // return resultHigh
      TR::Register *inputHigh = inputReg->getHighOrder();
      TR::Register *inputLow = inputReg->getLowOrder();
      TR::Register *resultHigh = numberOfLeadingZeros(node, cg, inputHigh, false, false);
      TR::Register *resultLow = numberOfLeadingZeros(node, cg, inputLow, false, false);
      TR::Register *maskReg = cg->allocateRegister();
      generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, maskReg, maskReg, cg);
      generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, inputHigh, 0, cg);
      generateRegInstruction(TR::InstOpCode::SETNE1Reg, node, maskReg, cg);
      generateRegInstruction(TR::InstOpCode::DEC4Reg, node, maskReg, cg);
      generateRegRegInstruction(TR::InstOpCode::AND4RegReg, node, resultLow, maskReg, cg);
      generateRegRegInstruction(TR::InstOpCode::ADD4RegReg, node, resultHigh, resultLow, cg);
      cg->stopUsingRegister(resultLow);
      cg->stopUsingRegister(maskReg);
      resultReg = resultHigh;
      }
   node->setRegister(resultReg);
   cg->decReferenceCount(child);
   return resultReg;
   }

static
TR::Register * numberOfTrailingZeros(TR::Node *node, TR::CodeGenerator *cg, TR::Register *reg, bool is64Bit, bool isLong)
   {
   // r1 is shift amount, r3 is the mask
   // xor r1, r1
   // bsf r2, reg
   // sete r1
   // mov r3, r1
   // dec r3
   // shl r1, is64Bit ? 6 : 5
   // and r2, r3
   // add r2, r1
   // return r2
   TR::Register *bsfReg = cg->allocateRegister();
   TR::Register *tempReg = cg->allocateRegister();
   TR::Register *maskReg = cg->allocateRegister();
   generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, tempReg, tempReg, cg);
   generateRegRegInstruction(TR::InstOpCode::BSFRegReg(is64Bit), node, bsfReg, reg, cg);
   generateRegInstruction(TR::InstOpCode::SETE1Reg, node, tempReg, cg);
   generateRegRegInstruction(TR::InstOpCode::MOVRegReg(is64Bit), node, maskReg, tempReg, cg);
   generateRegInstruction(TR::InstOpCode::DECReg(is64Bit), node, maskReg, cg);
   generateRegImmInstruction(TR::InstOpCode::SHLRegImm1(is64Bit), node, tempReg, isLong ? 6 : 5, cg);
   generateRegRegInstruction(TR::InstOpCode::ANDRegReg(is64Bit), node, bsfReg, maskReg, cg);
   generateRegRegInstruction(TR::InstOpCode::ADDRegReg(is64Bit), node, bsfReg, tempReg, cg);
   cg->stopUsingRegister(tempReg);
   cg->stopUsingRegister(maskReg);
   return bsfReg;
   }

TR::Register *J9::X86::TreeEvaluator::integerNumberOfTrailingZeros(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR_ASSERT(node->getNumChildren() == 1, "Node has a wrong number of children (i.e. !=1 )! ");
   TR::Node* child = node->getFirstChild();
   TR::Register* inputReg = cg->evaluate(child);
   TR::Register *resultReg = numberOfTrailingZeros(node, cg, inputReg, cg->comp()->target().is64Bit(), false);
   node->setRegister(resultReg);
   cg->decReferenceCount(child);
   return resultReg;
   }

TR::Register *J9::X86::TreeEvaluator::longNumberOfTrailingZeros(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR_ASSERT(node->getNumChildren() == 1, "Node has a wrong number of children (i.e. !=1 )! ");
   TR::Node * child = node->getFirstChild();
   TR::Register * inputReg = cg->evaluate(child);
   TR::Register * resultReg = NULL;
   if (cg->comp()->target().is64Bit())
      {
      resultReg = numberOfTrailingZeros(node, cg, inputReg, true, true);
      }
   else
      {
      // mask out result of high part if low part is not 32
      // xor r1, r1
      // cmp resultLow, 32
      // setne r1
      // dec r1
      // and r1, resultHigh
      // and resultLow, r1
      // return resultLow
      TR::Register *inputLow = inputReg->getLowOrder();
      TR::Register *inputHigh = inputReg->getHighOrder();
      TR::Register *maskReg = cg->allocateRegister();
      TR::Register *resultLow = numberOfTrailingZeros(node, cg, inputLow, false, false);
      TR::Register *resultHigh = numberOfTrailingZeros(node, cg, inputHigh, false, false);
      generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, maskReg, maskReg, cg);
      generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, resultLow, 32, cg);
      generateRegInstruction(TR::InstOpCode::SETNE1Reg, node, maskReg, cg);
      generateRegInstruction(TR::InstOpCode::DEC4Reg, node, maskReg, cg);
      generateRegRegInstruction(TR::InstOpCode::AND4RegReg, node, maskReg, resultHigh, cg);
      generateRegRegInstruction(TR::InstOpCode::ADD4RegReg, node, resultLow, maskReg, cg);
      cg->stopUsingRegister(resultHigh);
      cg->stopUsingRegister(maskReg);
      resultReg = resultLow;
      }
   node->setRegister(resultReg);
   cg->decReferenceCount(child);
   return resultReg;
   }

inline void generateInlinedCheckCastForDynamicCastClass(TR::Node* node, TR::CodeGenerator* cg)
   {
   TR::Compilation *comp = cg->comp();
   auto use64BitClasses = comp->target().is64Bit() &&
               (!TR::Compiler->om.generateCompressedObjectHeaders() ||
               (comp->compileRelocatableCode() && comp->getOption(TR_UseSymbolValidationManager)));
   TR::Register *ObjReg = cg->evaluate(node->getFirstChild());
   TR::Register *castClassReg = cg->evaluate(node->getSecondChild());
   TR::Register *temp1Reg = cg->allocateRegister();
   TR::Register *temp2Reg = cg->allocateRegister();
   TR::Register *objClassReg = cg->allocateRegister();

   bool isCheckCastAndNullCheck = (node->getOpCodeValue() == TR::checkcastAndNULLCHK);

   TR::LabelSymbol *startLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *fallThruLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *outlinedCallLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *throwLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *isClassLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *iTableLoopLabel = generateLabelSymbol(cg);
   startLabel->setStartInternalControlFlow();
   fallThruLabel->setEndInternalControlFlow();

   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

   TR_OutlinedInstructions *outlinedHelperCall = new (cg->trHeapMemory()) TR_OutlinedInstructions(node, TR::call, NULL, outlinedCallLabel, fallThruLabel, cg);
   cg->getOutlinedInstructionsList().push_front(outlinedHelperCall);

   // objClassReg holds object class also serves as null check
   if (isCheckCastAndNullCheck)
      generateLoadJ9Class(node, objClassReg, ObjReg, cg);

   // temp2Reg holds romClass of cast class, for testing array, interface class type
   generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, temp2Reg, generateX86MemoryReference(castClassReg, offsetof(J9Class, romClass), cg), cg);

   // If cast class is array, call out of line helper
   generateMemImmInstruction(TR::InstOpCode::TEST4MemImm4, node,
       generateX86MemoryReference(temp2Reg, offsetof(J9ROMClass, modifiers), cg), J9AccClassArray, cg);
   generateLabelInstruction(TR::InstOpCode::JNE4, node, outlinedCallLabel, cg);

   // objClassReg holds object class
   if (!isCheckCastAndNullCheck)
      {
      generateRegRegInstruction(TR::InstOpCode::TESTRegReg(), node, ObjReg, ObjReg, cg);
      generateLabelInstruction(TR::InstOpCode::JE4, node, fallThruLabel, cg);
      generateLoadJ9Class(node, objClassReg, ObjReg, cg);
      }

   // Object not array, inline checks
   // Check cast class is interface
   generateMemImmInstruction(TR::InstOpCode::TEST4MemImm4, node,
       generateX86MemoryReference(temp2Reg, offsetof(J9ROMClass, modifiers), cg), J9AccInterface, cg);
   generateLabelInstruction(TR::InstOpCode::JE4, node, isClassLabel, cg);

   // Obtain I-Table
   // temp1Reg holds head of J9Class->iTable of obj class
   generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, temp1Reg, generateX86MemoryReference(objClassReg, offsetof(J9Class, iTable), cg), cg);
   // Loop through I-Table
   // temp1Reg holds iTable list element through the loop
   generateLabelInstruction(TR::InstOpCode::label, node, iTableLoopLabel, cg);
   generateRegRegInstruction(TR::InstOpCode::TESTRegReg(), node, temp1Reg, temp1Reg, cg);
   generateLabelInstruction(TR::InstOpCode::JE4, node, throwLabel, cg);
   auto interfaceMR = generateX86MemoryReference(temp1Reg, offsetof(J9ITable, interfaceClass), cg);
   generateMemRegInstruction(TR::InstOpCode::CMPMemReg(), node, interfaceMR, castClassReg, cg);
   generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, temp1Reg, generateX86MemoryReference(temp1Reg, offsetof(J9ITable, next), cg), cg);
   generateLabelInstruction(TR::InstOpCode::JNE4, node, iTableLoopLabel, cg);

   // Found from I-Table
   generateLabelInstruction(TR::InstOpCode::JMP4, node, fallThruLabel, cg);

   // cast class is non-interface class
   generateLabelInstruction(TR::InstOpCode::label, node, isClassLabel, cg);
   // equality test
   generateRegRegInstruction(TR::InstOpCode::CMPRegReg(use64BitClasses), node, objClassReg, castClassReg, cg);
   generateLabelInstruction(TR::InstOpCode::JE4, node, fallThruLabel, cg);

   // class not equal
   // temp2 holds cast class depth
   // class depth mask must be low 16 bits to safely load without the mask.
   static_assert(J9AccClassDepthMask == 0xffff, "J9_JAVA_CLASS_DEPTH_MASK must be 0xffff");
   generateRegMemInstruction(comp->target().is64Bit()? TR::InstOpCode::MOVZXReg8Mem2 : TR::InstOpCode::MOVZXReg4Mem2, node,
            temp2Reg, generateX86MemoryReference(castClassReg, offsetof(J9Class, classDepthAndFlags), cg), cg);

   // cast class depth >= obj class depth, throw
   generateRegMemInstruction(TR::InstOpCode::CMP2RegMem, node, temp2Reg, generateX86MemoryReference(objClassReg, offsetof(J9Class, classDepthAndFlags), cg), cg);
   generateLabelInstruction(TR::InstOpCode::JAE4, node, throwLabel, cg);

   // check obj class's super class array entry
   // temp1Reg holds superClasses array of obj class
   // An alternative sequences requiring one less register may be:
   // SHL temp2Reg, 3 for 64-bit or 2 for 32-bit
   // ADD temp2Reg, [temp3Reg, superclasses offset]
   // CMP classClassReg, [temp2Reg]
   // On 64 bit, the extra reg isn't likely to cause significant register pressure.
   // On 32 bit, it could put more register pressure due to limited number of regs.
   // Since 64-bit is more prevalent, we opt to optimize for 64bit in this case
   generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, temp1Reg, generateX86MemoryReference(objClassReg, offsetof(J9Class, superclasses), cg), cg);
   generateRegMemInstruction(TR::InstOpCode::CMPRegMem(use64BitClasses), node, castClassReg,
       generateX86MemoryReference(temp1Reg, temp2Reg, comp->target().is64Bit()?3:2, cg), cg);
   generateLabelInstruction(TR::InstOpCode::JNE4, node, throwLabel, cg);

   // throw classCastException
   {
      TR_OutlinedInstructionsGenerator og(throwLabel, node, cg);
      generateRegInstruction(TR::InstOpCode::PUSHReg, node, objClassReg, cg);
      generateRegInstruction(TR::InstOpCode::PUSHReg, node, castClassReg, cg);
      auto call = generateHelperCallInstruction(node, TR_throwClassCastException, NULL, cg);
      call->setNeedsGCMap(0xFF00FFFF);
      call->setAdjustsFramePointerBy(-2*(int32_t)sizeof(J9Class*));
      og.endOutlinedInstructionSequence();
   }

   TR::RegisterDependencyConditions  *deps = generateRegisterDependencyConditions((uint8_t)0, 8, cg);

   deps->addPostCondition(ObjReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(castClassReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(temp1Reg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(temp2Reg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(objClassReg, TR::RealRegister::NoReg, cg);

   TR::Node *callNode = outlinedHelperCall->getCallNode();
   TR::Register *reg;

   if (callNode->getFirstChild() == node->getFirstChild())
      {
      reg = callNode->getFirstChild()->getRegister();
      if (reg)
         deps->unionPostCondition(reg, TR::RealRegister::NoReg, cg);
      }

   if (callNode->getSecondChild() == node->getSecondChild())
      {
      reg = callNode->getSecondChild()->getRegister();
      if (reg)
         deps->unionPostCondition(reg, TR::RealRegister::NoReg, cg);
      }

   deps->stopAddingConditions();

   generateLabelInstruction(TR::InstOpCode::label, node, fallThruLabel, deps, cg);

   cg->stopUsingRegister(temp1Reg);
   cg->stopUsingRegister(temp2Reg);
   cg->stopUsingRegister(objClassReg);

   // Decrement use counts on the children
   //
   cg->decReferenceCount(node->getFirstChild());
   cg->decReferenceCount(node->getSecondChild());
   }

static void
generateInlinedCheckCastOrInstanceOfForArrayClass(TR::Node *node, TR_OpaqueClassBlock *clazz, bool isCheckCast, TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());

   static char *disableInlineObjectArrayCheckCast = feGetEnv("TR_DisableInlineObjectArrayCheckCast");

   if (!disableInlineObjectArrayCheckCast && isCheckCast && clazz && TR::Compiler->cls.isClassArray(comp, clazz))
      {
      TR_OpaqueClassBlock *componentClass = fej9->getComponentClassFromArrayClass(clazz);
      if (fej9->isJavaLangObject(componentClass))
         {
         if (comp->getOption(TR_TraceCG))
            traceMsg(comp, "Inline checkcast for [jlO : node=%p", node);

         TR::LabelSymbol *outlinedCallLabel = generateLabelSymbol(cg);
         TR::LabelSymbol *fallThruLabel = generateLabelSymbol(cg);

         TR::Node *objectNode = node->getFirstChild();
         TR::Node *castClassNode = node->getSecondChild();
         TR::Register *objectReg = cg->evaluate(objectNode);
         TR::Register *objectClassReg = cg->allocateRegister();
         TR::Register *scratchReg = cg->allocateRegister();

         TR_OutlinedInstructions *outlinedHelperCall = new (cg->trHeapMemory()) TR_OutlinedInstructions(node, TR::call, NULL, outlinedCallLabel, fallThruLabel, cg);
         cg->getOutlinedInstructionsList().push_front(outlinedHelperCall);

         static char *breakOnInlineObjectArrayCheckCast = feGetEnv("TR_BreakOnInlineObjectArrayCheckCast");
         if (breakOnInlineObjectArrayCheckCast)
            generateInstruction(TR::InstOpCode::INT3, node, cg);

         // If the objectRef is NULL, the cast will succeed
         //
         if (!objectNode->isNonNull())
            {
            generateRegRegInstruction(TR::InstOpCode::TESTRegReg(), node, objectReg, objectReg, cg);
            generateLabelInstruction(TR::InstOpCode::JE4, node, fallThruLabel, cg);
            }

         // The cast class is an array of j/l/Objects. Check if the
         // object class is a non-primitive array
         //
         generateLoadJ9Class(node, objectClassReg, objectReg, cg);

         // Aliases for code readability only
         TR::Register *romClassReg = scratchReg,
                      *componentClassReg = scratchReg;

         // Check if romClass is an array
         //
         generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, romClassReg, generateX86MemoryReference(objectClassReg, offsetof(J9Class, romClass), cg), cg);
         generateMemImmInstruction(TR::InstOpCode::TEST4MemImm4, node,
            generateX86MemoryReference(romClassReg, offsetof(J9ROMClass, modifiers), cg), J9AccClassArray, cg);
         generateLabelInstruction(TR::InstOpCode::JE4, node, outlinedCallLabel, cg);

         // Check if object class is a primitive array
         generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, componentClassReg, generateX86MemoryReference(objectClassReg, offsetof(J9ArrayClass, componentType), cg), cg);
         generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, romClassReg, generateX86MemoryReference(componentClassReg, offsetof(J9Class, romClass), cg), cg);
         generateMemImmInstruction(TR::InstOpCode::TEST4MemImm4, node,
            generateX86MemoryReference(romClassReg, offsetof(J9ROMClass, modifiers), cg), J9AccClassInternalPrimitiveType, cg);
         generateLabelInstruction(TR::InstOpCode::JNE4, node, outlinedCallLabel, cg);

         TR::RegisterDependencyConditions  *deps = generateRegisterDependencyConditions((uint8_t)0, 5, cg);
         deps->addPostCondition(objectReg, TR::RealRegister::NoReg, cg);
         deps->addPostCondition(objectClassReg, TR::RealRegister::NoReg, cg);
         deps->addPostCondition(scratchReg, TR::RealRegister::NoReg, cg);

         TR::Node *callNode = outlinedHelperCall->getCallNode();
         TR::Register *reg;

         if (callNode->getFirstChild() == node->getFirstChild())
            {
            reg = callNode->getFirstChild()->getRegister();
            if (reg)
               deps->unionPostCondition(reg, TR::RealRegister::NoReg, cg);
            }

         if (callNode->getSecondChild() == node->getSecondChild())
            {
            reg = callNode->getSecondChild()->getRegister();
            if (reg)
               deps->unionPostCondition(reg, TR::RealRegister::NoReg, cg);
            }

         deps->stopAddingConditions();
         generateLabelInstruction(TR::InstOpCode::label, node, fallThruLabel, deps, cg);

         cg->stopUsingRegister(scratchReg);
         cg->stopUsingRegister(objectClassReg);

         cg->decReferenceCount(objectNode);
         cg->decReferenceCount(castClassNode);

         return;
         }
      }

   if (node->getOpCodeValue() == TR::checkcastAndNULLCHK)
      {
      auto object = cg->evaluate(node->getChild(0));
      // Just touch the memory in case this is a NULL pointer and we need to throw
      // the exception after the checkcast. If the checkcast was combined with nullpointer
      // there's nobody after the checkcast to throw the exception.
      auto instr = generateMemImmInstruction(TR::InstOpCode::TEST1MemImm1, node, generateX86MemoryReference(object, TR::Compiler->om.offsetOfObjectVftField(), cg), 0, cg);
      cg->setImplicitExceptionPoint(instr);
      instr->setNeedsGCMap(0xFF00FFFF);
      instr->setNode(comp->findNullChkInfo(node));
      }

   TR::TreeEvaluator::performHelperCall(node, NULL, isCheckCast ? TR::call : TR::icall, false, cg);
   }

/**
 * @brief Generate instructions to perform an interface table walk to search
 *        for a given cast class.  Handles both checkcast and instanceof.
 *
 * @param[in] node : \c TR::Node of the current check node
 * @param[in] cg : \c TR::CodeGenerator object
 * @param[in] iTableLookUpFailLabel : \c TR::LabelSymbol to handle the case where the cast class
 *               is not found during the itable walk
 * @param[in] castClass : \c J9::Class cast class address
 * @param[in] castClassReg : \c TR::Register scratch register to hold large cast class address,
 *               if necessary.  NULL means a scratch register is not required for the cast class.
 * @param[in] itableReg : \c TR::Register to use during itable walk
 */
static void inlineInterfaceLookup(
      TR::Node *node,
      TR::CodeGenerator *cg,
      TR::LabelSymbol *iTableLookUpFailLabel,
      TR_OpaqueClassBlock *castClass,
      TR::Register *castClassReg,
      TR::Register *itableReg)
   {
   TR::LabelSymbol *iTableLoopLabel = generateLabelSymbol(cg);

   if (castClassReg)
      {
      generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, castClassReg, reinterpret_cast<uintptr_t>(castClass), cg, TR_ClassAddress);
      }

   // Loop through I-Table
   generateLabelInstruction(TR::InstOpCode::label, node, iTableLoopLabel, cg);
   generateRegRegInstruction(TR::InstOpCode::TESTRegReg(), node, itableReg, itableReg, cg);
   generateLabelInstruction(TR::InstOpCode::JE4, node, iTableLookUpFailLabel, cg);
   auto interfaceMR = generateX86MemoryReference(itableReg, offsetof(J9ITable, interfaceClass), cg);
   if (castClassReg)
      {
      generateMemRegInstruction(TR::InstOpCode::CMP8MemReg, node, interfaceMR, castClassReg, cg);
      }
   else
      {
      generateMemImmSymInstruction(TR::InstOpCode::CMP4MemImm4, node, interfaceMR, reinterpret_cast<uintptr_t>(castClass), node->getChild(1)->getSymbolReference(), cg);
      }
   generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, itableReg, generateX86MemoryReference(itableReg, offsetof(J9ITable, next), cg), cg);
   generateLabelInstruction(TR::InstOpCode::JNE4, node, iTableLoopLabel, cg);

   // If the loop does not iterate then a match was found
   }


inline void generateInlinedCheckCastOrInstanceOfForInterface(
      TR::Node *node,
      TR_OpaqueClassBlock *castClass,
      TR::CodeGenerator *cg,
      bool isCheckCast)
   {
   TR::Compilation *comp = cg->comp();
   TR_ASSERT(castClass && TR::Compiler->cls.isInterfaceClass(comp, castClass), "Not a compile-time known Interface.");

   bool use64BitClasses = comp->target().is64Bit() &&
                             (!TR::Compiler->om.generateCompressedObjectHeaders() ||
                              (comp->compileRelocatableCode() && comp->getOption(TR_UseSymbolValidationManager)));

   // When running 64 bit compressed refs, if castClass is an address above the 2G boundary then we can't use
   // a push 32bit immediate instruction to pass it on the stack to the jitThrowClassCastException helper
   // as the address gets sign extended. It needs to be stored in a temp register and then push the
   // register to the stack.
   bool highClass = (comp->target().is64Bit() && ((uintptr_t)castClass) > INT_MAX);

   TR::Register *instanceClassReg = cg->allocateRegister();
   TR::Register *castClassReg = (use64BitClasses || highClass) ? cg->allocateRegister() : NULL;

   // Profiled call site cache
   uint8_t numSuccessfulClassChecks = 0;
   uintptr_t guessClass = 0;
   if (!comp->compileRelocatableCode())
      {
      TR_OpaqueClassBlock* guessClassArray[NUM_PICS];
      auto num_PICs = TR::TreeEvaluator::interpreterProfilingInstanceOfOrCheckCastInfo(cg, node, guessClassArray);
      auto fej9 = static_cast<TR_J9VMBase *>(comp->fe());
      for (uint8_t i = 0; i < num_PICs; i++)
         {
         if (fej9->instanceOfOrCheckCastNoCacheUpdate((J9Class*)guessClassArray[i], (J9Class*)castClass))
            {
            guessClass = reinterpret_cast<uintptr_t>(guessClassArray[i]);
            numSuccessfulClassChecks++;
            }
         }
      }

   /**
    * Only cache the last successful check if profiling strongly suggests this check
    * is monomorphic.  If profiling has seen more than one successful class check then
    * using a cache could cause performance problems as multiple threads compete to
    * update the single cached class.  If no successful class checks have been seen
    * before then do not speculate that a cache would be helpful.
    */
   bool doClassCache = (numSuccessfulClassChecks == 1) ? true : false;

   static bool disableInterfaceCastCache = feGetEnv("TR_forceDisableInterfaceCastCache") != NULL;
   static bool enableInterfaceCastCache = feGetEnv("TR_forceEnableInterfaceCastCache") != NULL;

   TR_ASSERT_FATAL(!(disableInterfaceCastCache && enableInterfaceCastCache),
      "checkcast interface cast cache cannot be both explicitly enabled and disabled");

   doClassCache = !disableInterfaceCastCache && (enableInterfaceCastCache || doClassCache);

   /**
    * A scratch register is required for ClassCastException throws when
    * a cache is not being used for checkcasts.
    */
   TR::Register *scratchReg = (!doClassCache && isCheckCast) ? cg->allocateRegister() : NULL;

   uint8_t numDeps = 1 + (castClassReg != NULL) + (scratchReg != NULL);
   auto deps = generateRegisterDependencyConditions(numDeps, numDeps, cg);
   deps->addPreCondition(instanceClassReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(instanceClassReg, TR::RealRegister::NoReg, cg);
   if (castClassReg)
      {
      deps->addPreCondition(castClassReg, TR::RealRegister::NoReg, cg);
      deps->addPostCondition(castClassReg, TR::RealRegister::NoReg, cg);
      }
   if (scratchReg)
      {
      deps->addPreCondition(scratchReg, TR::RealRegister::NoReg, cg);
      deps->addPostCondition(scratchReg, TR::RealRegister::NoReg, cg);
      }
   deps->stopAddingConditions();

   TR::LabelSymbol *begLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *endLabel = generateLabelSymbol(cg);
   begLabel->setStartInternalControlFlow();
   endLabel->setEndInternalControlFlow();

   TR::LabelSymbol *iTableLookUpPathLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *iTableLookUpFailLabel = generateLabelSymbol(cg);

   generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, instanceClassReg, node->getChild(0)->getRegister(), cg);
   generateLabelInstruction(TR::InstOpCode::label, node, begLabel, cg);

   // Null test
   if (!node->getChild(0)->isNonNull() && node->getOpCodeValue() != TR::checkcastAndNULLCHK)
      {
      // instanceClassReg contains the object at this point, reusing the register as object is no longer used after this point.
      generateRegRegInstruction(TR::InstOpCode::TESTRegReg(), node, instanceClassReg, instanceClassReg, cg);
      generateLabelInstruction(TR::InstOpCode::JE4, node, endLabel, cg);
      }

   // Load J9Class
   generateLoadJ9Class(node, instanceClassReg, instanceClassReg, cg);

   if (doClassCache)
      {
      // Call site cache
      auto cache = sizeof(J9Class*) == 4 ? cg->create4ByteData(node, (uint32_t)guessClass) : cg->create8ByteData(node, (uint64_t)guessClass);
      cache->setClassAddress(true);
      generateRegMemInstruction(TR::InstOpCode::CMPRegMem(use64BitClasses), node, instanceClassReg, generateX86MemoryReference(cache, cg), cg);
      generateLabelInstruction(TR::InstOpCode::JNE4, node, iTableLookUpPathLabel, cg);

      // I-Table lookup out-of-line
         {
         TR_OutlinedInstructionsGenerator og(iTableLookUpPathLabel, node, cg);

         // Preserve the instance class before the register is reused
         generateRegInstruction(TR::InstOpCode::PUSHReg, node, instanceClassReg, cg);

         // Save VFP
         auto vfp = generateVFPSaveInstruction(node, cg);

         // Obtain I-Table
         // Re-use the instanceClassReg register to perform itable lookup
         generateRegMemInstruction(
            TR::InstOpCode::LRegMem(),
            node,
            instanceClassReg,
            generateX86MemoryReference(instanceClassReg, offsetof(J9Class, iTable), cg),
            cg);

         inlineInterfaceLookup(
            node,
            cg,
            iTableLookUpFailLabel,
            castClass,
            castClassReg,
            instanceClassReg);

         // Found from I-Table

         /**
          * The original implementation of this interface cast cache operated as
          * an LRU cache.  This is suboptimal in the presence of multiple threads
          * executing this code with unique instance classes as it will lead to
          * significant thrashing on the processor caches to maintain coherency.
          * Disable behaving as an LRU cache by default, but leave an environment
          * variable to enable the original behaviour.
          */
         static bool updateCacheSlot = feGetEnv("TR_updateInterfaceCheckCastCacheSlot") != NULL;
         if (updateCacheSlot)
            {
            generateMemInstruction(TR::InstOpCode::POPMem, node, generateX86MemoryReference(cache, cg), cg); // j9class
            }
         else
            {
            generateRegInstruction(TR::InstOpCode::POPReg, node, instanceClassReg, cg); // j9class
            }

         if (!isCheckCast)
            {
            generateInstruction(TR::InstOpCode::STC, node, cg);
            }
         generateLabelInstruction(TR::InstOpCode::JMP4, node, endLabel, cg);

         // Not found
         generateVFPRestoreInstruction(vfp, node, cg);

         generateLabelInstruction(TR::InstOpCode::label, node, iTableLookUpFailLabel, cg);

         if (isCheckCast)
            {
            if (castClassReg)
               {
               generateRegInstruction(TR::InstOpCode::PUSHReg, node, castClassReg, cg);
               }
            else
               {
               generateImmInstruction(TR::InstOpCode::PUSHImm4, node, static_cast<int32_t>(reinterpret_cast<uintptr_t>(castClass)), cg);
               }
            auto call = generateHelperCallInstruction(node, TR_throwClassCastException, NULL, cg);
            call->setNeedsGCMap(0xFF00FFFF);
            call->setAdjustsFramePointerBy(-2*(int32_t)sizeof(J9Class*));
            }
         else
            {
            generateRegInstruction(TR::InstOpCode::POPReg, node, instanceClassReg, cg);
            generateLabelInstruction(TR::InstOpCode::JMP4, node, endLabel, cg);
            }

         og.endOutlinedInstructionSequence();
         }

      // Succeed
      if (!isCheckCast)
         {
         generateInstruction(TR::InstOpCode::STC, node, cg);
         }
      }
   else
      {
      /**
       * Do not use a cache.  Generate the interface lookup inline and the fail
       * path out-of-line.
       */

      /**
       * Use the scratch register if it is available.  Otherwise, re-use the
       * instanceClassReg register to perform itable lookup
       */
      TR::Register *itableReg = scratchReg ? scratchReg : instanceClassReg;

      // Obtain I-Table
      generateRegMemInstruction(
         TR::InstOpCode::LRegMem(),
         node,
         itableReg,
         generateX86MemoryReference(instanceClassReg, offsetof(J9Class, iTable), cg),
         cg);

      inlineInterfaceLookup(
         node,
         cg,
         isCheckCast ? iTableLookUpFailLabel : endLabel,
         castClass,
         castClassReg,
         itableReg);

      if (!isCheckCast)
         {
         // Class found in itable
         generateInstruction(TR::InstOpCode::STC, node, cg);

         // Fall through to endLabel
         }
      else
         {
         // CheckCast iTable fail lookup out-of-line
         TR_OutlinedInstructionsGenerator og(iTableLookUpFailLabel, node, cg);

         generateRegInstruction(TR::InstOpCode::PUSHReg, node, instanceClassReg, cg);

         if (castClassReg)
            {
            generateRegInstruction(TR::InstOpCode::PUSHReg, node, castClassReg, cg);
            }
         else
            {
            generateImmInstruction(TR::InstOpCode::PUSHImm4, node, static_cast<int32_t>(reinterpret_cast<uintptr_t>(castClass)), cg);
            }
         auto call = generateHelperCallInstruction(node, TR_throwClassCastException, NULL, cg);
         call->setNeedsGCMap(0xFF00FFFF);
         call->setAdjustsFramePointerBy(-2*(int32_t)sizeof(J9Class*));

         og.endOutlinedInstructionSequence();
         }
      }

   generateLabelInstruction(TR::InstOpCode::label, node, endLabel, deps, cg);

   cg->stopUsingRegister(instanceClassReg);

   if (castClassReg)
      {
      cg->stopUsingRegister(castClassReg);
      }

   if (scratchReg)
      {
      cg->stopUsingRegister(scratchReg);
      }
   }


inline void generateInlinedCheckCastOrInstanceOfForClass(TR::Node* node, TR_OpaqueClassBlock* clazz, TR::CodeGenerator* cg, bool isCheckCast)
   {
   TR::Compilation *comp = cg->comp();
   auto fej9 = (TR_J9VMBase*)(cg->fe());

   bool use64BitClasses = false;
   if (comp->target().is64Bit())
      {
      // When running 64 bit compressed refs, if clazz is an address above the 2G
      // boundary then we can't use a push 32bit immediate instruction to pass it
      // to the helper as the address gets sign extended. So we need to test for
      // this case and switch to the 64bit memory to memory encoding
      // that is used when running 64 bit non-compressed.
      auto highClass = ((uintptr_t)clazz) > INT_MAX;

      use64BitClasses = !TR::Compiler->om.generateCompressedObjectHeaders() ||
                        highClass ||
                        (comp->compileRelocatableCode() && comp->getOption(TR_UseSymbolValidationManager));
      }

   auto clazzData = use64BitClasses ? cg->create8ByteData(node, (uint64_t)(uintptr_t)clazz) : NULL;
   if (clazzData)
      {
      clazzData->setClassAddress(true);
      }

   auto j9class = cg->allocateRegister();
   auto tmp = cg->allocateRegister();

   auto deps = generateRegisterDependencyConditions((uint8_t)2, (uint8_t)2, cg);
   deps->addPreCondition(tmp, TR::RealRegister::NoReg, cg);
   deps->addPreCondition(j9class, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(tmp, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(j9class, TR::RealRegister::NoReg, cg);

   auto begLabel = generateLabelSymbol(cg);
   auto endLabel = generateLabelSymbol(cg);
   begLabel->setStartInternalControlFlow();
   endLabel->setEndInternalControlFlow();

   auto successLabel = isCheckCast ? endLabel : generateLabelSymbol(cg);
   auto failLabel    = isCheckCast ? generateLabelSymbol(cg) : endLabel;

   generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, j9class, node->getChild(0)->getRegister(), cg);
   generateLabelInstruction(TR::InstOpCode::label, node, begLabel, cg);

   // Null test
   if (!node->getChild(0)->isNonNull() && node->getOpCodeValue() != TR::checkcastAndNULLCHK)
      {
      // j9class contains the object at this point, reusing the register as object is no longer used after this point.
      generateRegRegInstruction(TR::InstOpCode::TESTRegReg(), node, j9class, j9class, cg);
      generateLabelInstruction(TR::InstOpCode::JE4, node, endLabel, cg);
      }

   // Load J9Class
   generateLoadJ9Class(node, j9class, j9class, cg);

   // Equality test
   if (!fej9->isAbstractClass(clazz) || node->getOpCodeValue() == TR::icall/*TR_checkAssignable*/)
      {
      // For instanceof and checkcast, LHS is obtained from an instance, which cannot be abstract or interface;
      // therefore, equality test can be safely skipped for instanceof and checkcast when RHS is abstract.
      // However, LHS for TR_checkAssignable may be abstract or interface as it may be an arbitrary class, and
      // hence equality test is always needed.
      if (use64BitClasses)
         {
         generateRegMemInstruction(TR::InstOpCode::CMP8RegMem, node, j9class, generateX86MemoryReference(clazzData, cg), cg);
         }
      else
         {
         generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, j9class, (uintptr_t)clazz, cg);
         }
      if (!fej9->isClassFinal(clazz))
         {
         generateLabelInstruction(TR::InstOpCode::JE4, node, successLabel, cg);
         }
      }
   // at this point, ZF == 1 indicates success

   // Superclass test
   if (!fej9->isClassFinal(clazz))
      {
      auto depth = TR::Compiler->cls.classDepthOf(clazz);
      if (depth >= comp->getOptions()->_minimumSuperclassArraySize)
         {
         static_assert(J9AccClassDepthMask == 0xffff, "J9AccClassDepthMask must be 0xffff");
         auto depthMR = generateX86MemoryReference(j9class, offsetof(J9Class, classDepthAndFlags), cg);
         generateMemImmInstruction(TR::InstOpCode::CMP2MemImm2, node, depthMR, depth, cg);
         if (!isCheckCast)
            {
            // Need ensure CF is cleared before reaching to fail label
            auto outlineLabel = generateLabelSymbol(cg);
            generateLabelInstruction(TR::InstOpCode::JBE4, node, outlineLabel, cg);

            TR_OutlinedInstructionsGenerator og(outlineLabel, node, cg);
            generateInstruction(TR::InstOpCode::CLC, node, cg);
            generateLabelInstruction(TR::InstOpCode::JMP4, node, failLabel, cg);
            og.endOutlinedInstructionSequence();
            }
         else
            {
            generateLabelInstruction(TR::InstOpCode::JBE4, node, failLabel, cg);
            }
         }

      generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, tmp, generateX86MemoryReference(j9class, offsetof(J9Class, superclasses), cg), cg);
      auto offset = depth * sizeof(J9Class*);
      TR_ASSERT(IS_32BIT_SIGNED(offset), "The offset to superclass is unreasonably large.");
      auto superclass = generateX86MemoryReference(tmp, offset, cg);
      if (use64BitClasses)
         {
         generateRegMemInstruction(TR::InstOpCode::L8RegMem, node, tmp, superclass, cg);
         generateRegMemInstruction(TR::InstOpCode::CMP8RegMem, node, tmp, generateX86MemoryReference(clazzData, cg), cg);
         }
      else
         {
         generateMemImmInstruction(TR::InstOpCode::CMP4MemImm4, node, superclass, (int32_t)(uintptr_t)clazz, cg);
         }
      }
   // at this point, ZF == 1 indicates success

   // Branch to success/fail path
   if (!isCheckCast)
      {
      generateInstruction(TR::InstOpCode::CLC, node, cg);
      }
   generateLabelInstruction(TR::InstOpCode::JNE4, node, failLabel, cg);

   // Set CF to report success
   if (!isCheckCast)
      {
      generateLabelInstruction(TR::InstOpCode::label, node, successLabel, cg);
      generateInstruction(TR::InstOpCode::STC, node, cg);
      }

   // Throw exception for CheckCast
   if (isCheckCast)
      {
      TR_OutlinedInstructionsGenerator og(failLabel, node, cg);

      generateRegInstruction(TR::InstOpCode::PUSHReg, node, j9class, cg);
      if (use64BitClasses)
         {
         generateMemInstruction(TR::InstOpCode::PUSHMem, node, generateX86MemoryReference(clazzData, cg), cg);
         }
      else
         {
         generateImmInstruction(TR::InstOpCode::PUSHImm4, node, (int32_t)(uintptr_t)clazz, cg);
         }
      auto call = generateHelperCallInstruction(node, TR_throwClassCastException, NULL, cg);
      call->setNeedsGCMap(0xFF00FFFF);
      call->setAdjustsFramePointerBy(-2*(int32_t)sizeof(J9Class*));

      og.endOutlinedInstructionSequence();
      }

   // Succeed
   generateLabelInstruction(TR::InstOpCode::label, node, endLabel, deps, cg);

   cg->stopUsingRegister(j9class);
   cg->stopUsingRegister(tmp);
   }

TR::Register *J9::X86::TreeEvaluator::checkcastinstanceofEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();

   bool isCheckCast = false;
   switch (node->getOpCodeValue())
      {
      case TR::checkcast:
      case TR::checkcastAndNULLCHK:
         isCheckCast = true;
         break;
      case TR::instanceof:
      case TR::icall: // TR_checkAssignable
         break;
      default:
         TR_ASSERT(false, "Incorrect Op Code %d.", node->getOpCodeValue());
         break;
      }
   TR_OpaqueClassBlock *clazz = TR::TreeEvaluator::getCastClassAddress(node->getChild(1));
   if (isCheckCast && !clazz && !comp->getOption(TR_DisableInlineCheckCast) && (!comp->compileRelocatableCode() || comp->getOption(TR_UseSymbolValidationManager)))
      {
      generateInlinedCheckCastForDynamicCastClass(node, cg);
      }
   else if (clazz &&
       !TR::Compiler->cls.isClassArray(comp, clazz) && // not yet optimized
       (!comp->compileRelocatableCode() || comp->getOption(TR_UseSymbolValidationManager)) &&
       !comp->getOption(TR_DisableInlineCheckCast)  &&
       !comp->getOption(TR_DisableInlineInstanceOf))
      {
      cg->evaluate(node->getChild(0));
      if (TR::Compiler->cls.isInterfaceClass(comp, clazz))
         {
         generateInlinedCheckCastOrInstanceOfForInterface(node, clazz, cg, isCheckCast);
         }
      else
         {
         generateInlinedCheckCastOrInstanceOfForClass(node, clazz, cg, isCheckCast);
         }
      if (!isCheckCast)
         {
         auto result = cg->allocateRegister();
         generateRegInstruction(TR::InstOpCode::SETB1Reg, node, result, cg);
         generateRegRegInstruction(TR::InstOpCode::MOVZXReg4Reg1, node, result, result, cg);
         node->setRegister(result);
         }
      cg->decReferenceCount(node->getChild(0));
      cg->recursivelyDecReferenceCount(node->getChild(1));
      }
   else
      {
      generateInlinedCheckCastOrInstanceOfForArrayClass(node, clazz, isCheckCast, cg);
      }
   return node->getRegister();
   }

static TR::MemoryReference *getMemoryReference(TR::Register *objectClassReg, TR::Register *objectReg, int32_t lwOffset, TR::CodeGenerator *cg)
   {
   if (objectClassReg)
      return generateX86MemoryReference(objectReg, objectClassReg, 0, cg);
   else
      return generateX86MemoryReference(objectReg, lwOffset, cg);
   }

void J9::X86::TreeEvaluator::asyncGCMapCheckPatching(TR::Node *node, TR::CodeGenerator *cg, TR::LabelSymbol *snippetLabel)
   {
   TR::MemoryReference *SOMmr = generateX86MemoryReference(node->getFirstChild()->getFirstChild(), cg);
   TR::Compilation *comp = cg->comp();

   if (cg->comp()->target().is64Bit())
      {
      //64 bit sequence
      //
      //Generate a call to the out-of-line patching sequence.
      //This sequence will convert the call back into an asynch message check cmp
      //
      TR::LabelSymbol *gcMapPatchingLabel = generateLabelSymbol(cg);
      TR::LabelSymbol *outlinedStartLabel = generateLabelSymbol(cg);
      TR::LabelSymbol *outlinedEndLabel = generateLabelSymbol(cg);
      TR::LabelSymbol *asyncWithoutPatch = generateLabelSymbol(cg);

      //Start inline patching sequence
      //
      TR::Register *patchableAddrReg = cg->allocateRegister();
      TR::Register *patchValReg = cg->allocateRegister();
      TR::Register *tempReg = cg->allocateRegister();


      outlinedStartLabel->setStartInternalControlFlow();
      outlinedEndLabel->setEndInternalControlFlow();

      //generateLabelInstruction(TR::InstOpCode::CALLImm4, node, gcMapPatchingLabel, cg);
      generatePatchableCodeAlignmentInstruction(TR::X86PatchableCodeAlignmentInstruction::CALLImm4AtomicRegions, generateLabelInstruction(TR::InstOpCode::CALLImm4, node, gcMapPatchingLabel, cg), cg);

      TR_OutlinedInstructionsGenerator og(gcMapPatchingLabel, node, cg);

      generateLabelInstruction(TR::InstOpCode::label, node, outlinedStartLabel, cg);
      //Load the address that we are going to patch and clean up the stack
      //
      generateRegInstruction(TR::InstOpCode::POPReg, node, patchableAddrReg, cg);

      //check if there is already an async even pending
      //
      generateMemImmInstruction(TR::InstOpCode::CMP8MemImm4, node, SOMmr, -1, cg);
      generateLabelInstruction(TR::InstOpCode::JE4, node, asyncWithoutPatch, cg);

      //Signal the async event
      //
      static char *d = feGetEnv("TR_GCOnAsyncBREAK");
      if (d)
         generateInstruction(TR::InstOpCode::INT3, node, cg);

      generateMemImmInstruction(TR::InstOpCode::S8MemImm4, node, generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, stackOverflowMark), cg), -1, cg);
      generateRegImmInstruction(TR::InstOpCode::MOV8RegImm4, node, tempReg, 1 << comp->getPersistentInfo()->getGCMapCheckEventHandle(), cg);
      generateMemRegInstruction(TR::InstOpCode::LOR8MemReg, node, generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, asyncEventFlags),cg), tempReg, cg);

      //Populate the code we are going to patch in
      //
      //existing
      //000007ff`7d340578 e8f4170000      call    000007ff`7d341d71  <------
      //000007ff`7d34057d 0f84ee1e0000    je      000007ff`7d342471
      //*********
      //patching in
      //000007ff'7d34056f 48837d50ff      cmp qword ptr [rbp+0x50], 0xffffffffffffffff   <-----
      //000007ff`7d34057d 0f84ee1e0000    je      000007ff`7d342471

      //Load the original value
      //

      generateRegMemInstruction(TR::InstOpCode::L8RegMem, node, patchValReg, generateX86MemoryReference(patchableAddrReg, -5, cg), cg);
      generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, tempReg, (uint64_t) 0x0, cg);
      generateRegRegInstruction(TR::InstOpCode::OR8RegReg, node, patchValReg, tempReg, cg);
      generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, tempReg, (uint64_t) 0x0, cg);
      generateRegRegInstruction(TR::InstOpCode::AND8RegReg, node, patchValReg, tempReg , cg);

      TR::RegisterDependencyConditions *deps = generateRegisterDependencyConditions((uint8_t)0, 4, cg);
      deps->addPostCondition(patchableAddrReg, TR::RealRegister::NoReg, cg);
      deps->addPostCondition(patchValReg, TR::RealRegister::NoReg, cg);
      deps->addPostCondition(tempReg, TR::RealRegister::NoReg, cg);
      deps->addPostCondition(cg->getVMThreadRegister(), TR::RealRegister::ebp, cg);
      deps->stopAddingConditions();

      generateMemRegInstruction(TR::InstOpCode::S8MemReg, node, generateX86MemoryReference(patchableAddrReg, -5, cg), patchValReg, deps, cg);
      generateLabelInstruction(TR::InstOpCode::label, node, asyncWithoutPatch, cg);
      generateLabelInstruction(TR::InstOpCode::JMP4, node, snippetLabel, cg);

      cg->stopUsingRegister(patchableAddrReg);
      cg->stopUsingRegister(patchValReg);
      cg->stopUsingRegister(tempReg);
      generateLabelInstruction(TR::InstOpCode::label, node, outlinedEndLabel, cg);

      og.endOutlinedInstructionSequence();
      }
  else
      {
      //32 bit sequence
      //

      //Generate a call to the out-of-line patching sequence.
      //This sequence will convert the call back into an asynch message check cmp
      //
      TR::LabelSymbol *gcMapPatchingLabel = generateLabelSymbol(cg);
      TR::LabelSymbol *outlinedStartLabel = generateLabelSymbol(cg);
      TR::LabelSymbol *outlinedEndLabel = generateLabelSymbol(cg);
      TR::LabelSymbol *asyncWithoutPatch = generateLabelSymbol(cg);

      //Start inline patching sequence
      //
      TR::Register *patchableAddrReg = cg->allocateRegister();
      TR::Register *lowPatchValReg = cg->allocateRegister();
      TR::Register *highPatchValReg = cg->allocateRegister();
      TR::Register *lowExistingValReg = cg->allocateRegister();
      TR::Register *highExistingValReg = cg->allocateRegister();

      outlinedStartLabel->setStartInternalControlFlow();
      outlinedEndLabel->setEndInternalControlFlow();

      //generateBoundaryAvoidanceInstruction(TR::X86BoundaryAvoidanceInstruction::CALLImm4AtomicRegions, 8, 8,generateLabelInstruction(TR::InstOpCode::CALLImm4, node, gcMapPatchingLabel, cg), cg);
      TR::Instruction *callInst =  generatePatchableCodeAlignmentInstruction(TR::X86PatchableCodeAlignmentInstruction::CALLImm4AtomicRegions, generateLabelInstruction(TR::InstOpCode::CALLImm4, node, gcMapPatchingLabel, cg), cg);
      TR::X86VFPSaveInstruction *vfpSaveInst = generateVFPSaveInstruction(callInst->getPrev(), cg);

      TR_OutlinedInstructionsGenerator og(gcMapPatchingLabel, node, cg);

      generateLabelInstruction(TR::InstOpCode::label, node, outlinedStartLabel, cg);
      //Load the address that we are going to patch and clean up the stack
      //
      generateRegInstruction(TR::InstOpCode::POPReg, node, patchableAddrReg, cg);


      //check if there is already an async even pending
      //
      generateMemImmInstruction(TR::InstOpCode::CMP4MemImm4, node, SOMmr, -1, cg);
      generateLabelInstruction(TR::InstOpCode::JE4, node, asyncWithoutPatch, cg);

      //Signal the async event
      //
      generateMemImmInstruction(TR::InstOpCode::S4MemImm4, node, generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, stackOverflowMark), cg), -1, cg);
      generateRegImmInstruction(TR::InstOpCode::MOV4RegImm4, node, lowPatchValReg, 1 << comp->getPersistentInfo()->getGCMapCheckEventHandle(), cg);
      generateMemRegInstruction(TR::InstOpCode::LOR4MemReg, node, generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, asyncEventFlags),cg), lowPatchValReg, cg);

      //Populate the registers we are going to use in the lock cmp xchg
      //

      static char *d = feGetEnv("TR_GCOnAsyncBREAK");
      if (d)
         generateInstruction(TR::InstOpCode::INT3, node, cg);

      //Populate the existing inline code
      //
      generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, lowExistingValReg, generateX86MemoryReference(patchableAddrReg, -5, cg), cg);
      generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, highExistingValReg, generateX86MemoryReference(patchableAddrReg, -1, cg), cg);

      //Populate the code we are going to patch in
      //837d28ff        cmp     dword ptr [ebp+28h],0FFFFFFFFh <--- patching in
      //90              nop
      //*******************
      //                call imm4                              <---- patching over
      //
      generateRegImmInstruction(TR::InstOpCode::MOV4RegImm4, node, lowPatchValReg, (uint32_t) 0x287d8390, cg);
      generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, highPatchValReg, highExistingValReg, cg);
      generateRegImmInstruction(TR::InstOpCode::OR4RegImm4, node, highPatchValReg, (uint32_t) 0x000000ff, cg);

      TR::RegisterDependencyConditions *deps = generateRegisterDependencyConditions((uint8_t)0, 6, cg);

      deps->addPostCondition(patchableAddrReg, TR::RealRegister::edi, cg);
      deps->addPostCondition(lowPatchValReg, TR::RealRegister::ebx, cg);
      deps->addPostCondition(highPatchValReg, TR::RealRegister::ecx, cg);
      deps->addPostCondition(lowExistingValReg, TR::RealRegister::eax, cg);
      deps->addPostCondition(highExistingValReg, TR::RealRegister::edx, cg);
      deps->addPostCondition(cg->getVMThreadRegister(), TR::RealRegister::ebp, cg);
      deps->stopAddingConditions();
      generateMemInstruction(TR::InstOpCode::LCMPXCHG8BMem, node, generateX86MemoryReference(patchableAddrReg, -5, cg), deps, cg);
      generateLabelInstruction(TR::InstOpCode::label, node, asyncWithoutPatch, cg);
      generateVFPRestoreInstruction(generateLabelInstruction(TR::InstOpCode::JMP4, node, snippetLabel, cg),vfpSaveInst,cg);

      cg->stopUsingRegister(patchableAddrReg);
      cg->stopUsingRegister(lowPatchValReg);
      cg->stopUsingRegister(highPatchValReg);
      cg->stopUsingRegister(lowExistingValReg);
      cg->stopUsingRegister(highExistingValReg);
      generateLabelInstruction(TR::InstOpCode::label, node, outlinedEndLabel, cg);

      og.endOutlinedInstructionSequence();
     }
  }

void J9::X86::TreeEvaluator::inlineRecursiveMonitor(
      TR::Node *node,
      TR::CodeGenerator *cg,
      TR::LabelSymbol *fallThruLabel,
      TR::LabelSymbol *jitMonitorEnterOrExitSnippetLabel,
      TR::LabelSymbol *inlineRecursiveSnippetLabel,
      TR::Register *objectReg,
      int lwOffset,
      TR::LabelSymbol *snippetRestartLabel,
      bool reservingLock)
   {
   // Code generated:
   //
   // outlinedStartLabel:
   //    mov lockWordReg, [obj+lwOffset]
   //    add lockWordReg, INC_DEC_VALUE/-INC_DEC_VALUE  ---> lock word with increased recursive count
   //    mov lockWordMaskedReg, NON_INC_DEC_MASK
   //    and lockWordMaskedReg, lockWordReg  ---> lock word masked out counter bits
   //    cmp lockWordMaskedReg, vmThreadReg
   //    jne jitMonitorEnterOrExitSnippetLabel
   //    mov [obj+lwOffset], lockWordReg
   //
   // #if defined(TR_TARGET_64BIT) && (JAVA_SPEC_VERSION >= 19)
   //    inc|dec [vmThreadReg + ownedMonitorCountOffset]
   // #endif
   //
   // snippetRestartLabel:
   //    jmp fallThruLabel
   // outlinedEndLabel:
   //
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());
   TR::LabelSymbol *outlinedStartLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *outlinedEndLabel = generateLabelSymbol(cg);

   outlinedStartLabel->setStartInternalControlFlow();
   outlinedEndLabel->setEndInternalControlFlow();

   TR_OutlinedInstructionsGenerator og(inlineRecursiveSnippetLabel, node, cg);

   generateLabelInstruction(TR::InstOpCode::label, node, outlinedStartLabel, cg);
   TR::Register *lockWordReg = cg->allocateRegister();
   TR::Register *lockWordMaskedReg = cg->allocateRegister();
   TR::Register *vmThreadReg = cg->getVMThreadRegister();
   bool use64bitOp = cg->comp()->target().is64Bit() && !fej9->generateCompressedLockWord();
   bool isMonitorEnter = node->getSymbolReference() == cg->comp()->getSymRefTab()->findOrCreateMethodMonitorEntrySymbolRef(NULL)
                       ||  node->getSymbolReference() == cg->comp()->getSymRefTab()->findOrCreateMonitorEntrySymbolRef(NULL);

   generateRegMemInstruction(TR::InstOpCode::LRegMem(use64bitOp), node, lockWordReg, generateX86MemoryReference(objectReg, lwOffset, cg), cg);
   generateRegImmInstruction(TR::InstOpCode::ADDRegImm4(use64bitOp), node, lockWordReg, isMonitorEnter? INC_DEC_VALUE: -INC_DEC_VALUE, cg);
   generateRegImmInstruction(TR::InstOpCode::MOVRegImm4(use64bitOp), node, lockWordMaskedReg, NON_INC_DEC_MASK - RES_BIT, cg);
   generateRegRegInstruction(TR::InstOpCode::ANDRegReg(use64bitOp), node, lockWordMaskedReg, lockWordReg, cg);
   generateRegRegInstruction(TR::InstOpCode::CMPRegReg(use64bitOp), node, lockWordMaskedReg, vmThreadReg, cg);

   generateLabelInstruction(TR::InstOpCode::JNE4, node, jitMonitorEnterOrExitSnippetLabel, cg);
   generateMemRegInstruction(TR::InstOpCode::SMemReg(use64bitOp), node, generateX86MemoryReference(objectReg, lwOffset, cg), lockWordReg, cg);

#if defined(TR_TARGET_64BIT) && (JAVA_SPEC_VERSION >= 19)
   // Adjust J9VMThread ownedMonitorCount for execution paths that do not
   // go out of line to acquire the lock.  It is safe and efficient to do
   // this unconditionally.  There is no need to check for overflow or
   // underflow.
   //
   generateMemInstruction(
      isMonitorEnter ? TR::InstOpCode::INC8Mem : TR::InstOpCode::DEC8Mem,
      node,
      generateX86MemoryReference(vmThreadReg, fej9->thisThreadGetOwnedMonitorCountOffset(), cg),
      cg);
#endif

   TR::RegisterDependencyConditions *restartDeps = generateRegisterDependencyConditions((uint8_t)0, 4, cg);
   restartDeps->addPostCondition(objectReg, TR::RealRegister::NoReg, cg);
   restartDeps->addPostCondition(vmThreadReg, TR::RealRegister::ebp, cg);
   restartDeps->addPostCondition(lockWordMaskedReg, TR::RealRegister::NoReg, cg);
   restartDeps->addPostCondition(lockWordReg, TR::RealRegister::NoReg, cg);
   restartDeps->stopAddingConditions();
   generateLabelInstruction(TR::InstOpCode::label, node, snippetRestartLabel, restartDeps, cg);

   generateLabelInstruction(TR::InstOpCode::JMP4, node, fallThruLabel, cg);

   cg->stopUsingRegister(lockWordReg);
   cg->stopUsingRegister(lockWordMaskedReg);

   TR::RegisterDependencyConditions *deps = generateRegisterDependencyConditions((uint8_t)0, 1, cg);
   deps->addPostCondition(vmThreadReg, TR::RealRegister::ebp, cg);
   deps->stopAddingConditions();
   generateLabelInstruction(TR::InstOpCode::label, node, outlinedEndLabel, deps, cg);

   og.endOutlinedInstructionSequence();
   }

void
J9::X86::TreeEvaluator::generateCheckForValueMonitorEnterOrExit(
      TR::Node *node,
      int32_t classFlag,
      TR::LabelSymbol *snippetLabel,
      TR::CodeGenerator *cg)
   {
   TR::Register *objectReg = cg->evaluate(node->getFirstChild());
   TR::Register *j9classReg = cg->allocateRegister();
   generateLoadJ9Class(node, j9classReg, objectReg, cg);
   auto fej9 = (TR_J9VMBase *)(cg->fe());
   TR::MemoryReference *classFlagsMR = generateX86MemoryReference(j9classReg, (uintptr_t)(fej9->getOffsetOfClassFlags()), cg);

   TR::InstOpCode::Mnemonic testOpCode;
   if ((uint32_t)classFlag <= USHRT_MAX)
      testOpCode = TR::InstOpCode::TEST2MemImm2;
   else
      testOpCode = TR::InstOpCode::TEST4MemImm4;

   generateMemImmInstruction(testOpCode, node, classFlagsMR, classFlag, cg);
   generateLabelInstruction(TR::InstOpCode::JNE4, node, snippetLabel, cg);
   }

TR::Register *
J9::X86::TreeEvaluator::VMmonentEvaluator(
      TR::Node *node,
      TR::CodeGenerator *cg)
   {
   // If there is a NULLCHK above this node it will be expecting us to set
   // up the excepting instruction. If we are not going to inline an
   // appropriate excepting instruction we must make sure to reset the
   // excepting instruction since our children may have set it.
   //
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());
   bool is64Bit = comp->target().is64Bit();

   static const char *noInline = feGetEnv("TR_NoInlineMonitor");
   bool reservingLock = false;
   bool normalLockPreservingReservation = false;
   bool dummyMethodMonitor = false;
   TR_YesNoMaybe isMonitorValueBasedOrValueType = cg->isMonitorValueBasedOrValueType(node);

   int lwOffset = fej9->getByteOffsetToLockword((TR_OpaqueClassBlock *) cg->getMonClass(node));
   if (comp->getOption(TR_MimicInterpreterFrameShape) ||
       (comp->getOption(TR_FullSpeedDebug) && node->isSyncMethodMonitor()) ||
       noInline ||
       (isMonitorValueBasedOrValueType == TR_yes) ||
       comp->getOption(TR_DisableInlineMonEnt))
      {
      // Don't inline
      //
      TR::ILOpCodes opCode = node->getOpCodeValue();
      TR::Node::recreate(node, TR::call);
      TR::TreeEvaluator::directCallEvaluator(node, cg);
      TR::Node::recreate(node, opCode);
      cg->setImplicitExceptionPoint(NULL);
      return NULL;
      }

   if (lwOffset > 0 && comp->getOption(TR_ReservingLocks))
      {
      bool dummy=false;
      TR::TreeEvaluator::evaluateLockForReservation (node, &reservingLock, &normalLockPreservingReservation, cg);
      TR::TreeEvaluator::isPrimitiveMonitor (node, cg);

      if (node->isPrimitiveLockedRegion() && reservingLock)
         dummyMethodMonitor = TR::TreeEvaluator::isDummyMonitorEnter(node, cg);

      if (reservingLock && !node->isPrimitiveLockedRegion())
         dummyMethodMonitor = false;
      }

   TR::Node *objectRef = node->getFirstChild();

   static const char *disableInlineRecursiveEnv = feGetEnv("TR_DisableInlineRecursiveMonitor");
   bool inlineRecursive = disableInlineRecursiveEnv ? false : true;
   if (lwOffset <= 0)
     inlineRecursive = false;

   // Evaluate the object reference
   //
   TR::Register *objectReg = cg->evaluate(objectRef);
   TR::Register *eaxReal   = cg->allocateRegister();
   TR::Register *scratchReg = NULL;
   uint32_t numDeps = 3; // objectReg, eax, ebp

   cg->setImplicitExceptionPoint(NULL);

   TR::LabelSymbol *startLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *fallThruLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *inlinedMonEnterFallThruLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *snippetFallThruLabel = inlineRecursive ? generateLabelSymbol(cg) : fallThruLabel;

   startLabel->setStartInternalControlFlow();
   fallThruLabel->setEndInternalControlFlow();
   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

   TR::Register *vmThreadReg = cg->getVMThreadRegister();

   TR::LabelSymbol *snippetLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *monitorLookupCacheLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *fallThruFromMonitorLookupCacheLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *exitLabel = NULL;

   TR_OutlinedInstructions *outlinedHelperCall;
   // In the reserving lock case below, we change the symref on the node... Here, we are going to store the original symref, so that we can restore our change.
   TR::SymbolReference *originalNodeSymRef = NULL;

   TR::Node *helperCallNode = node;

   if (isMonitorValueBasedOrValueType == TR_maybe)
      TR::TreeEvaluator::generateCheckForValueMonitorEnterOrExit(node, J9_CLASS_DISALLOWS_LOCKING_FLAGS, snippetLabel, cg);

   if (comp->getOption(TR_ReservingLocks))
      {
      // About to change the node's symref... store the original.
      originalNodeSymRef = node->getSymbolReference();

      if (reservingLock && node->isPrimitiveLockedRegion() && dummyMethodMonitor)
         {
         TR_RuntimeHelper monExitHelper = (node->getSymbolReference() == cg->getSymRef(TR_methodMonitorEntry)) ?
            TR_AMD64JitMethodMonitorExitReservedPrimitive : TR_AMD64JitMonitorExitReservedPrimitive;

         node->setSymbolReference(comp->getSymRefTab()->findOrCreateRuntimeHelper(monExitHelper, true, true, true));

         exitLabel = generateLabelSymbol(cg);
         TR_OutlinedInstructions *outlinedExitHelperCall = new (cg->trHeapMemory()) TR_OutlinedInstructions(node, TR::call, NULL, exitLabel, fallThruLabel, cg);
         cg->getOutlinedInstructionsList().push_front(outlinedExitHelperCall);
         }

      TR_RuntimeHelper helper;
      bool success = TR::TreeEvaluator::monEntryExitHelper(true, node, reservingLock, normalLockPreservingReservation, helper, cg);
      if (success)
         node->setSymbolReference(comp->getSymRefTab()->findOrCreateRuntimeHelper(helper, true, true, true));

      if (reservingLock)
         {
         uint32_t reservableLwValue = RES_BIT;
         if (TR::Options::_aggressiveLockReservation)
            reservableLwValue = 0;

         // Make this integer the same size as the lock word. If we always
         // passed a 32-bit value, then on 64-bit with an uncompressed lock
         // word, the helper would have to either zero-extend the value, or
         // rely on the caller having done so even though the calling
         // convention doesn't appear to require it.
         TR::Node *reservableLwNode = NULL;
         if (comp->target().is32Bit() || fej9->generateCompressedLockWord())
            reservableLwNode = TR::Node::iconst(node, reservableLwValue);
         else
            reservableLwNode = TR::Node::lconst(node, reservableLwValue);

         helperCallNode = TR::Node::create(
            node,
            TR::call,
            2,
            objectRef,
            reservableLwNode);

         helperCallNode->setSymbolReference(node->getSymbolReference());
         helperCallNode->incReferenceCount();
         }
      }

   outlinedHelperCall = new (cg->trHeapMemory()) TR_OutlinedInstructions(helperCallNode, TR::call, NULL,
                                                      snippetLabel, (exitLabel) ? exitLabel : snippetFallThruLabel, cg);

   if (helperCallNode != node)
      helperCallNode->recursivelyDecReferenceCount();

   cg->getOutlinedInstructionsList().push_front(outlinedHelperCall);
   cg->generateDebugCounter(
          outlinedHelperCall->getFirstInstruction(),
          TR::DebugCounter::debugCounterName(comp, "helperCalls/%s/(%s)/%d/%d", node->getOpCode().getName(), comp->signature(), node->getByteCodeInfo().getCallerIndex(), node->getByteCodeInfo().getByteCodeIndex()),
          1, TR::DebugCounter::Cheap);

   // Okay, and we've made it down here and we've successfully generated all outlined snippets, let's restore the node's symref.
   if (comp->getOption(TR_ReservingLocks))
      {
      node->setSymbolReference(originalNodeSymRef);
      }

   if (inlineRecursive)
      {
      TR::LabelSymbol *inlineRecursiveSnippetLabel = generateLabelSymbol(cg);
      TR::LabelSymbol *jitMonitorEnterSnippetLabel = snippetLabel;
      snippetLabel = inlineRecursiveSnippetLabel;
      TR::TreeEvaluator::inlineRecursiveMonitor(node, cg, fallThruLabel, jitMonitorEnterSnippetLabel, inlineRecursiveSnippetLabel, objectReg, lwOffset, snippetFallThruLabel, reservingLock);
      }

   // Compare the monitor slot in the object against zero.  If it succeeds
   // we are done.  Else call the helper.
   // Code generated:
   //    xor     eax, eax
   //    cmpxchg monitor(objectReg), ebp
   //    jne     snippet
   //    label   restartLabel
   //
   // Code generated for read monitor enter:
   //    xor     eax, eax
   //    mov     lockedReg, INC_DEC_VALUE (0x04)
   //    cmpxchg monitor(objectReg), lockedReg
   //    jne     snippet
   //    label   restartLabel
   //
   TR::Register *lockedReg = NULL;
   TR::InstOpCode::Mnemonic op = TR::InstOpCode::bad;

   bool isSMP = comp->target().isSMP();
   if (is64Bit && !fej9->generateCompressedLockWord())
      {
      op = isSMP ? TR::InstOpCode::LCMPXCHG8MemReg : TR::InstOpCode::CMPXCHG8MemReg;
      }
   else
      {
      op = isSMP ? TR::InstOpCode::LCMPXCHG4MemReg : TR::InstOpCode::CMPXCHG4MemReg;
      }

   TR::Register *objectClassReg = NULL;
   TR::Register *lookupOffsetReg = NULL;

   if (lwOffset <= 0)
      {
      TR::MemoryReference *objectClassMR = generateX86MemoryReference(objectReg, TMP_OFFSETOF_J9OBJECT_CLAZZ, cg);
      objectClassReg = cg->allocateRegister();
      numDeps++;

      TR::InstOpCode::Mnemonic loadOp = (TR::Compiler->om.compressObjectReferences()) ? TR::InstOpCode::L4RegMem : TR::InstOpCode::LRegMem();
      TR::X86RegMemInstruction *instr = generateRegMemInstruction(loadOp, node, objectClassReg, objectClassMR, cg);

      // This instruction may try to dereference a null memory address
      // add an implicit exception point for it.
      //
      cg->setImplicitExceptionPoint(instr);
      instr->setNeedsGCMap(0xFF00FFFF);

      TR::TreeEvaluator::generateVFTMaskInstruction(node, objectClassReg, cg);
      int32_t offsetOfLockOffset = offsetof(J9Class, lockOffset);
      generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, objectClassReg, generateX86MemoryReference(objectClassReg, offsetOfLockOffset, cg), cg);
      generateRegImmInstruction(TR::InstOpCode::CMPRegImms(), node, objectClassReg, 0, cg);

      generateCommonLockNurseryCodes(
         node,
         cg,
         true, //true for VMmonentEvaluator, false for VMmonexitEvaluator
         monitorLookupCacheLabel,
         fallThruFromMonitorLookupCacheLabel,
         snippetLabel,
         numDeps,
         lwOffset,
         objectClassReg,
         lookupOffsetReg,
         vmThreadReg,
         objectReg);
      }

   if (comp->getOption(TR_ReservingLocks) && reservingLock)
      {
      TR::LabelSymbol *mismatchLabel = TR::Options::_aggressiveLockReservation ? snippetLabel : generateLabelSymbol(cg);

      generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, eaxReal, generateX86MemoryReference(vmThreadReg, RES_BIT, cg), cg);

      TR::InstOpCode::Mnemonic cmpMemRegOp = (is64Bit && fej9->generateCompressedLockWord()) ?
         TR::InstOpCode::CMP4MemReg : TR::InstOpCode::CMPMemReg(is64Bit);
      TR::X86MemRegInstruction *instr = generateMemRegInstruction(cmpMemRegOp, node, getMemoryReference(objectClassReg, objectReg, lwOffset, cg), eaxReal, cg);

      cg->setImplicitExceptionPoint(instr);
      instr->setNeedsGCMap(0xFF00FFFF);

      generateLabelInstruction(TR::InstOpCode::JNE4, node, mismatchLabel, cg);

      if (!node->isPrimitiveLockedRegion())
         {
         TR::InstOpCode::Mnemonic addMemImmOp = (is64Bit && fej9->generateCompressedLockWord()) ?
            TR::InstOpCode::ADD4MemImms : TR::InstOpCode::ADDMemImms();
         generateMemImmInstruction(addMemImmOp, node, getMemoryReference(objectClassReg, objectReg, lwOffset, cg), REC_BIT, cg);
         }

      if (!TR::Options::_aggressiveLockReservation)
         {
         // Jump over the non-reservable path
         generateLabelInstruction(TR::InstOpCode::JMP4, node, inlinedMonEnterFallThruLabel, cg);

         // It's possible that the lock may be available, but not reservable. In
         // that case we should try the usual cmpxchg for non-reserving enter.
         // Otherwise we'll necessarily call the helper.
         generateLabelInstruction(TR::InstOpCode::label, node, mismatchLabel, cg);

         TR::InstOpCode::Mnemonic cmpMemImmOp = (is64Bit && fej9->generateCompressedLockWord()) ?
            TR::InstOpCode::CMP4MemImms : TR::InstOpCode::CMPMemImms();

         auto lwMR = getMemoryReference(objectClassReg, objectReg, lwOffset, cg);
         generateMemImmInstruction(cmpMemImmOp, node, lwMR, 0, cg);
         generateLabelInstruction(TR::InstOpCode::JNE4, node, snippetLabel, cg);
         generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, eaxReal, eaxReal, cg);
         lwMR = getMemoryReference(objectClassReg, objectReg, lwOffset, cg);
         generateMemRegInstruction(op, node, lwMR, vmThreadReg, cg);
         generateLabelInstruction(TR::InstOpCode::JNE4, node, snippetLabel, cg);
         }
      }
   else
      {
      if (TR::Options::_aggressiveLockReservation)
         {
         if (comp->getOption(TR_ReservingLocks) && normalLockPreservingReservation)
            {
            TR::InstOpCode::Mnemonic cmpMemImmOp = (is64Bit && fej9->generateCompressedLockWord()) ?
               TR::InstOpCode::CMP4MemImms : TR::InstOpCode::CMPMemImms();

            TR::X86MemImmInstruction *instr =
               generateMemImmInstruction(cmpMemImmOp, node, getMemoryReference(objectClassReg, objectReg, lwOffset, cg), 0, cg);

            cg->setImplicitExceptionPoint(instr);
            instr->setNeedsGCMap(0xFF00FFFF);

            generateLabelInstruction(TR::InstOpCode::JNE4, node, snippetLabel, cg);
            }

         generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, eaxReal, eaxReal, cg);
         }
      else if (!comp->getOption(TR_ReservingLocks))
         {
         generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, eaxReal, eaxReal, cg);
         }
      else
         {
         TR::InstOpCode::Mnemonic loadOp = TR::InstOpCode::LRegMem();
         TR::InstOpCode::Mnemonic testOp = TR::InstOpCode::TESTRegImm4();
         if (is64Bit && fej9->generateCompressedLockWord())
            {
            loadOp = TR::InstOpCode::L4RegMem;
            testOp = TR::InstOpCode::TEST4RegImm4;
            }

         auto lwMR = getMemoryReference(objectClassReg, objectReg, lwOffset, cg);
         auto instr = generateRegMemInstruction(loadOp, node, eaxReal, lwMR, cg);
         cg->setImplicitExceptionPoint(instr);
         instr->setNeedsGCMap(0xFF00FFFF);

         generateRegImmInstruction(testOp, node, eaxReal, (int32_t)~RES_BIT, cg);
         generateLabelInstruction(TR::InstOpCode::JNE4, node, snippetLabel, cg);
         }

      if (node->isReadMonitor())
         {
         lockedReg = cg->allocateRegister();
         if (is64Bit && fej9->generateCompressedLockWord())
            generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, lockedReg, lockedReg, cg);  //After lockedReg is allocated zero it out.
         generateRegImmInstruction(TR::InstOpCode::MOVRegImm4(), node, lockedReg, INC_DEC_VALUE, cg);
         ++numDeps;
         }
      else
         {
         bool conditionallyReserve = false;
         bool shouldConditionallyReserveForReservableClasses =
            comp->getOption(TR_ReservingLocks)
            && !TR::Options::_aggressiveLockReservation
            && lwOffset > 0
            && cg->getMonClass(node) != NULL;

         if (shouldConditionallyReserveForReservableClasses)
            {
            TR_PersistentClassInfo *monClassInfo = comp
               ->getPersistentInfo()
               ->getPersistentCHTable()
               ->findClassInfoAfterLocking(cg->getMonClass(node), comp);

            if (monClassInfo != NULL && monClassInfo->isReservable())
               conditionallyReserve = true;
            }

         if (!conditionallyReserve)
            {
            // we want to write thread reg into lock word
            lockedReg = vmThreadReg;
            }
         else
            {
            lockedReg = cg->allocateRegister();
            numDeps++;

            // Compute the value to put into the lock word based on the
            // current value, which is either 0 or RES_BIT ("reservable").
            //
            //    0       ==> vmThreadReg
            //    RES_BIT ==> vmThreadReg | RES_BIT | INC_DEC_VALUE
            //
            // For reservable locks, failure to reserve at this point would
            // prevent any future reservation of the same lock.

            bool b64 = is64Bit && !fej9->generateCompressedLockWord();
            generateRegRegInstruction(TR::InstOpCode::MOVRegReg(b64), node, lockedReg, eaxReal, cg);
            generateRegImmInstruction(TR::InstOpCode::SHRRegImm1(b64), node, lockedReg, RES_BIT_POSITION, cg);
            generateRegInstruction(TR::InstOpCode::NEGReg(b64), node, lockedReg, cg);
            generateRegImmInstruction(TR::InstOpCode::ANDRegImms(b64), node, lockedReg, RES_BIT | INC_DEC_VALUE, cg);
            generateRegRegInstruction(TR::InstOpCode::ADDRegReg(b64), node, lockedReg, vmThreadReg, cg);
            }
         }

      // try to swap into lock word
      TR::X86MemRegInstruction  *instr = generateMemRegInstruction(op, node, getMemoryReference(objectClassReg, objectReg, lwOffset, cg), lockedReg, cg);
      cg->setImplicitExceptionPoint(instr);
      instr->setNeedsGCMap(0xFF00FFFF);

      generateLabelInstruction(TR::InstOpCode::JNE4, node, snippetLabel, cg);
      }

   generateLabelInstruction(TR::InstOpCode::label, node, inlinedMonEnterFallThruLabel, cg);

#if defined(TR_TARGET_64BIT) && (JAVA_SPEC_VERSION >= 19)
   // Adjust J9VMThread ownedMonitorCount for execution paths that do not
   // go out of line to acquire the lock.  It is safe and efficient to do
   // this unconditionally.  There is no need to check for overflow..
   //
   generateMemInstruction(
      TR::InstOpCode::INC8Mem,
      node,
      generateX86MemoryReference(vmThreadReg, fej9->thisThreadGetOwnedMonitorCountOffset(), cg),
      cg);
#endif

   // Create dependencies for the registers used.
   // The dependencies must be in the order:
   //      objectReg, eaxReal, vmThreadReg
   // since the snippet needs to find them to grab the real registers from them.
   //
   TR::RegisterDependencyConditions *deps = generateRegisterDependencyConditions((uint8_t)0, (uint8_t)numDeps, cg);
   deps->addPostCondition(objectReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(eaxReal, TR::RealRegister::eax, cg);
   deps->addPostCondition(vmThreadReg, TR::RealRegister::ebp, cg);

   if (scratchReg)
      deps->addPostCondition(scratchReg, TR::RealRegister::NoReg, cg);

   if (lockedReg != NULL && lockedReg != vmThreadReg)
      {
      deps->addPostCondition(lockedReg, TR::RealRegister::NoReg, cg);
      }

   if (objectClassReg)
      deps->addPostCondition(objectClassReg, TR::RealRegister::NoReg, cg);

   if (lookupOffsetReg)
      deps->addPostCondition(lookupOffsetReg, TR::RealRegister::NoReg, cg);

   deps->stopAddingConditions();

   generateLabelInstruction(TR::InstOpCode::label, node, fallThruLabel, deps, cg);

   cg->decReferenceCount(objectRef);
   cg->stopUsingRegister(eaxReal);
   if (scratchReg)
      cg->stopUsingRegister(scratchReg);
   if (objectClassReg)
      cg->stopUsingRegister(objectClassReg);
   if (lookupOffsetReg)
      cg->stopUsingRegister(lookupOffsetReg);

   if (lockedReg != NULL && lockedReg != vmThreadReg)
      {
      cg->stopUsingRegister(lockedReg);
      }

   return NULL;
   }

TR::Register *
J9::X86::TreeEvaluator::VMmonexitEvaluator(
      TR::Node          *node,
      TR::CodeGenerator *cg)
   {
   // If there is a NULLCHK above this node it will be expecting us to set
   // up the excepting instruction.  If we are not going to inline an
   // appropriate excepting instruction we must make sure to reset the
   // excepting instruction since our children may have set it.
   //
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());
   static const char *noInline = feGetEnv("TR_NoInlineMonitor");
   bool reservingLock = false;
   bool normalLockPreservingReservation = false;
   bool dummyMethodMonitor = false;
   bool gen64BitInstr = cg->comp()->target().is64Bit() && !fej9->generateCompressedLockWord();
   int lwOffset = fej9->getByteOffsetToLockword((TR_OpaqueClassBlock *) cg->getMonClass(node));
   TR_YesNoMaybe isMonitorValueBasedOrValueType = cg->isMonitorValueBasedOrValueType(node);

   if (comp->getOption(TR_MimicInterpreterFrameShape) ||
       noInline ||
       (isMonitorValueBasedOrValueType == TR_yes) ||
       comp->getOption(TR_DisableInlineMonExit))
      {
      // Don't inline
      //
      TR::ILOpCodes opCode = node->getOpCodeValue();
      TR::Node::recreate(node, TR::call);
      TR::TreeEvaluator::directCallEvaluator(node, cg);
      TR::Node::recreate(node, opCode);
      cg->setImplicitExceptionPoint(NULL);
      return NULL;
      }

   if (lwOffset > 0 && comp->getOption(TR_ReservingLocks))
      {
      TR::TreeEvaluator::evaluateLockForReservation (node, &reservingLock, &normalLockPreservingReservation, cg);
      if (node->isPrimitiveLockedRegion() && reservingLock)
         dummyMethodMonitor = TR::TreeEvaluator::isDummyMonitorExit(node, cg);

      if (!node->isPrimitiveLockedRegion() && reservingLock)
         dummyMethodMonitor = false;
      }

   if (dummyMethodMonitor)
      {
      cg->decReferenceCount(node->getFirstChild());
      return NULL;
      }

   static const char *disableInlineRecursiveEnv = feGetEnv("TR_DisableInlineRecursiveMonitor");
   bool inlineRecursive = disableInlineRecursiveEnv ? false : true;
   if (lwOffset <= 0)
     inlineRecursive = false;

   // Evaluate the object reference
   //
   TR::Node     *objectRef = node->getFirstChild();
   TR::Register *objectReg = cg->evaluate(objectRef);
   TR::Register *tempReg  = NULL;
   uint32_t     numDeps   = 2; // objectReg, ebp

   cg->setImplicitExceptionPoint(NULL);
   TR::Register *vmThreadReg = cg->getVMThreadRegister();

   TR::LabelSymbol *startLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *fallThruLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *inlinedMonExitFallThruLabel = generateLabelSymbol(cg);
   // Create the monitor exit snippet
   TR::LabelSymbol *snippetLabel = generateLabelSymbol(cg);

   if (isMonitorValueBasedOrValueType == TR_maybe)
      TR::TreeEvaluator::generateCheckForValueMonitorEnterOrExit(node, J9_CLASS_DISALLOWS_LOCKING_FLAGS, snippetLabel, cg);

   startLabel->setStartInternalControlFlow();
   TR::LabelSymbol *snippetFallThruLabel = inlineRecursive ? generateLabelSymbol(cg): fallThruLabel;
   fallThruLabel->setEndInternalControlFlow();
   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

   TR::Register *eaxReal = NULL;
   TR::Register *unlockedReg = NULL;
   TR::Register *scratchReg = NULL;

   TR::Register *objectClassReg = NULL;
   TR::Register *lookupOffsetReg = NULL;

   TR::LabelSymbol *monitorLookupCacheLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *fallThruFromMonitorLookupCacheLabel = generateLabelSymbol(cg);

   if (lwOffset <= 0)
      {
      TR::MemoryReference *objectClassMR = generateX86MemoryReference(objectReg, TMP_OFFSETOF_J9OBJECT_CLAZZ, cg);
      TR::InstOpCode::Mnemonic op = TR::Compiler->om.compressObjectReferences() ? TR::InstOpCode::L4RegMem : TR::InstOpCode::LRegMem();
      objectClassReg = cg->allocateRegister();

      TR::Instruction *instr = generateRegMemInstruction(op, node, objectClassReg, objectClassMR, cg);

      //this instruction may try to dereference a null memory address
      //add an implicit exception point for it.
      cg->setImplicitExceptionPoint(instr);
      instr->setNeedsGCMap(0xFF00FFFF);

      TR::TreeEvaluator::generateVFTMaskInstruction(node, objectClassReg, cg);
      int32_t offsetOfLockOffset = offsetof(J9Class, lockOffset);
      generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, objectClassReg, generateX86MemoryReference(objectClassReg, offsetOfLockOffset, cg), cg);

      numDeps++;

      generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, objectClassReg, 0, cg);

      generateCommonLockNurseryCodes(node,
                               cg,
                               false, //true for VMmonentEvaluator, false for VMmonexitEvaluator
                               monitorLookupCacheLabel,
                               fallThruFromMonitorLookupCacheLabel,
                               snippetLabel,
                               numDeps,
                               lwOffset,
                               objectClassReg,
                               lookupOffsetReg,
                               vmThreadReg,
                               objectReg);
      }

   // This is a normal inlined monitor exit
   //
   // Compare the monitor slot in the object against the thread register.
   // If it succeeds we are done. Else call the helper.
   //
   // Code generated:
   //    cmp   ebp, monitor(objectReg)
   //    jne   snippet
   //    test  flags(objectReg), FLC-bit     ; Only if FLC in separate word
   //    jne   snippet
   //    mov   monitor(objectReg), 0
   //    label restartLabel
   //
   // Code generated for read monitor:
   //    xor   unlockedReg, unlockedReg
   //    mov   eax, INC_DEC_VALUE
   //    (lock)cmpxchg   monitor(objectReg), unlockedReg
   //    jne   snippet
   //    label restartLabel
   //
   if (comp->getOption(TR_ReservingLocks))
      {
      if (reservingLock)
         {
         tempReg = cg->allocateRegister();
         numDeps++;
         }

      if (reservingLock || normalLockPreservingReservation)
         {
         TR_RuntimeHelper helper;
         bool success = TR::TreeEvaluator::monEntryExitHelper(false, node, reservingLock, normalLockPreservingReservation, helper, cg);

         TR_ASSERT(success == true, "monEntryExitHelper: could not find runtime helper");

         node->setSymbolReference(comp->getSymRefTab()->findOrCreateRuntimeHelper(helper, true, true, true));
         }
      }

   TR_OutlinedInstructions *outlinedHelperCall = new (cg->trHeapMemory()) TR_OutlinedInstructions(node, TR::call, NULL, snippetLabel, snippetFallThruLabel, cg);
   cg->getOutlinedInstructionsList().push_front(outlinedHelperCall);
   cg->generateDebugCounter(
      outlinedHelperCall->getFirstInstruction(),
      TR::DebugCounter::debugCounterName(comp, "helperCalls/%s/(%s)/%d/%d", node->getOpCode().getName(), comp->signature(), node->getByteCodeInfo().getCallerIndex(), node->getByteCodeInfo().getByteCodeIndex()),
      1, TR::DebugCounter::Cheap);

   if (inlineRecursive)
      {
      TR::LabelSymbol *inlineRecursiveSnippetLabel = generateLabelSymbol(cg);
      TR::LabelSymbol *jitMonitorExitSnippetLabel = snippetLabel;
      snippetLabel = inlineRecursiveSnippetLabel;
      TR::TreeEvaluator::inlineRecursiveMonitor(node, cg, fallThruLabel, jitMonitorExitSnippetLabel, inlineRecursiveSnippetLabel, objectReg, lwOffset, snippetFallThruLabel, reservingLock);
      }

   bool reservingDecrementNeeded = false;

   if (node->isReadMonitor())
      {
      unlockedReg = cg->allocateRegister();
      eaxReal     = cg->allocateRegister();
      generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, unlockedReg, unlockedReg, cg);
      generateRegImmInstruction(TR::InstOpCode::MOVRegImm4(), node, eaxReal, INC_DEC_VALUE, cg);

      TR::InstOpCode::Mnemonic op = cg->comp()->target().isSMP() ? TR::InstOpCode::LCMPXCHGMemReg(gen64BitInstr) : TR::InstOpCode::CMPXCHGMemReg(gen64BitInstr);
      cg->setImplicitExceptionPoint(generateMemRegInstruction(op, node, getMemoryReference(objectClassReg, objectReg, lwOffset, cg), unlockedReg, cg));
      numDeps += 2;
      }
   else
      {
      if (reservingLock)
         {
         if (node->isPrimitiveLockedRegion())
            {
            cg->setImplicitExceptionPoint(
               generateRegMemInstruction(
                  TR::InstOpCode::LRegMem(gen64BitInstr), node,
                  tempReg,
                  getMemoryReference(objectClassReg, objectReg, lwOffset, cg),
                  cg));

            // Mask out the thread ID and reservation count
            generateRegImmInstruction(TR::InstOpCode::ANDRegImms(), node, tempReg, FLAGS_MASK, cg);
            // If only the RES flag is set and no other we can continue
            generateRegImmInstruction(TR::InstOpCode::XORRegImms(), node, tempReg, RES_BIT, cg);
            }
         else
            {
            reservingDecrementNeeded = true;
            generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, tempReg, generateX86MemoryReference(vmThreadReg, (REC_BIT | RES_BIT), cg), cg);
            cg->setImplicitExceptionPoint(
               generateMemRegInstruction(
                  TR::InstOpCode::CMPMemReg(gen64BitInstr), node,
                  getMemoryReference(objectClassReg, objectReg, lwOffset, cg),
                  tempReg,
                  cg));
            }
         }
      else
         {
         cg->setImplicitExceptionPoint(
            generateRegMemInstruction(
               TR::InstOpCode::CMPRegMem(gen64BitInstr), node,
               vmThreadReg,
               getMemoryReference(objectClassReg, objectReg, lwOffset, cg),
               cg));
         }
      }

   TR::LabelSymbol *mismatchLabel = (reservingLock && !TR::Options::_aggressiveLockReservation) ? generateLabelSymbol(cg) : snippetLabel;

   generateLabelInstruction(TR::InstOpCode::JNE4, node, mismatchLabel, cg);

   if (reservingDecrementNeeded)
      {
      // Subtract the reservation count
      generateMemImmInstruction(TR::InstOpCode::SUBMemImms(gen64BitInstr), node,
         getMemoryReference(objectClassReg, objectReg, lwOffset, cg), REC_BIT, cg);  // I'm not sure TR::InstOpCode::SUB4MemImms will work.
      }

   if (!node->isReadMonitor() && !reservingLock)
      {
      generateMemImmInstruction(TR::InstOpCode::SMemImm4(gen64BitInstr), node,
         getMemoryReference(objectClassReg, objectReg, lwOffset, cg), 0, cg);
      }

   if (reservingLock && !TR::Options::_aggressiveLockReservation)
      {
      generateLabelInstruction(TR::InstOpCode::JMP4, node, inlinedMonExitFallThruLabel, cg);

      // Avoid the helper for non-recursive exit in case it isn't reserved
      generateLabelInstruction(TR::InstOpCode::label, node, mismatchLabel, cg);
      auto lwMR = getMemoryReference(objectClassReg, objectReg, lwOffset, cg);
      generateMemRegInstruction(TR::InstOpCode::CMPMemReg(gen64BitInstr), node, lwMR, vmThreadReg, cg);
      generateLabelInstruction(TR::InstOpCode::JNE4, node, snippetLabel, cg);
      lwMR = getMemoryReference(objectClassReg, objectReg, lwOffset, cg);
      generateMemImmInstruction(TR::InstOpCode::SMemImm4(gen64BitInstr), node, lwMR, 0, cg);
      }

   generateLabelInstruction(TR::InstOpCode::label, node, inlinedMonExitFallThruLabel, cg);

#if defined(TR_TARGET_64BIT) && (JAVA_SPEC_VERSION >= 19)
   // Adjust J9VMThread ownedMonitorCount for execution paths that do not
   // go out of line to release the lock.  It is safe and efficient to do
   // this unconditionally.  There is no need to check for underflow.
   //
   generateMemInstruction(
      TR::InstOpCode::DEC8Mem,
      node,
      generateX86MemoryReference(vmThreadReg, fej9->thisThreadGetOwnedMonitorCountOffset(), cg),
      cg);
#endif

   // Create dependencies for the registers used.
   // The first dependencies must be objectReg, vmThreadReg, tempReg
   // Or, for readmonitors they must be objectReg, vmThreadReg, unlockedReg, eaxReal
   // snippet needs to find them to grab the real registers from them.
   //
   TR::RegisterDependencyConditions *deps = generateRegisterDependencyConditions((uint8_t)0, (uint8_t)numDeps, cg);
   deps->addPostCondition(objectReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(vmThreadReg, TR::RealRegister::ebp, cg);

   if (node->isReadMonitor())
      {
      deps->addPostCondition(unlockedReg, TR::RealRegister::NoReg, cg);
      deps->addPostCondition(eaxReal, TR::RealRegister::eax, cg);
      }

   if (lookupOffsetReg)
      deps->addPostCondition(lookupOffsetReg, TR::RealRegister::NoReg, cg);

   if (tempReg && !node->isReadMonitor())
      deps->addPostCondition(tempReg, TR::RealRegister::NoReg, cg);
   if (scratchReg)
      deps->addPostCondition(scratchReg, TR::RealRegister::NoReg, cg);
   if (objectClassReg)
      deps->addPostCondition(objectClassReg, TR::RealRegister::NoReg, cg);

   deps->stopAddingConditions();
   generateLabelInstruction(TR::InstOpCode::label, node, fallThruLabel, deps, cg);

   if (eaxReal)
      cg->stopUsingRegister(eaxReal);
   if (unlockedReg)
      cg->stopUsingRegister(unlockedReg);

   cg->decReferenceCount(objectRef);
   if (tempReg)
      cg->stopUsingRegister(tempReg);

   if (scratchReg)
      cg->stopUsingRegister(scratchReg);

   if (objectClassReg)
      cg->stopUsingRegister(objectClassReg);

   if (lookupOffsetReg)
      cg->stopUsingRegister(lookupOffsetReg);

   return NULL;
   }


bool J9::X86::TreeEvaluator::monEntryExitHelper(
      bool entry,
      TR::Node* node,
      bool reservingLock,
      bool normalLockPreservingReservation,
      TR_RuntimeHelper &helper,
      TR::CodeGenerator* cg)
   {
   bool methodMonitor = entry
      ? (node->getSymbolReference() == cg->getSymRef(TR_methodMonitorEntry))
      : (node->getSymbolReference() == cg->getSymRef(TR_methodMonitorExit));

   if (reservingLock)
      {
      if (node->isPrimitiveLockedRegion())
         {
         static TR_RuntimeHelper helpersCase1[2][2][2] =
            {
               {
                  {TR_IA32JitMonitorExitReservedPrimitive, TR_IA32JitMethodMonitorExitReservedPrimitive},
                  {TR_AMD64JitMonitorExitReservedPrimitive, TR_AMD64JitMethodMonitorExitReservedPrimitive}
               },
               {
                  {TR_IA32JitMonitorEnterReservedPrimitive, TR_IA32JitMethodMonitorEnterReservedPrimitive},
                  {TR_AMD64JitMonitorEnterReservedPrimitive, TR_AMD64JitMethodMonitorEnterReservedPrimitive}
               }
            };

         helper = helpersCase1[entry?1:0][cg->comp()->target().is64Bit()?1:0][methodMonitor?1:0];
         return true;
         }
      else
         {
         static TR_RuntimeHelper helpersCase2[2][2][2] =
            {
               {
                  {TR_IA32JitMonitorExitReserved, TR_IA32JitMethodMonitorExitReserved},
                  {TR_AMD64JitMonitorExitReserved, TR_AMD64JitMethodMonitorExitReserved}
               },
               {
                  {TR_IA32JitMonitorEnterReserved, TR_IA32JitMethodMonitorEnterReserved},
                  {TR_AMD64JitMonitorEnterReserved, TR_AMD64JitMethodMonitorEnterReserved}
               }
            };

         helper = helpersCase2[entry?1:0][cg->comp()->target().is64Bit()?1:0][methodMonitor?1:0];
         return true;
         }
      }
   else if (normalLockPreservingReservation)
      {
      static TR_RuntimeHelper helpersCase2[2][2][2] =
         {
            {
               {TR_IA32JitMonitorExitPreservingReservation, TR_IA32JitMethodMonitorExitPreservingReservation},
               {TR_AMD64JitMonitorExitPreservingReservation, TR_AMD64JitMethodMonitorExitPreservingReservation}
            },
            {
               {TR_IA32JitMonitorEnterPreservingReservation, TR_IA32JitMethodMonitorEnterPreservingReservation},
               {TR_AMD64JitMonitorEnterPreservingReservation, TR_AMD64JitMethodMonitorEnterPreservingReservation}
            }
         };

      helper = helpersCase2[entry?1:0][cg->comp()->target().is64Bit()?1:0][methodMonitor?1:0];
      return true;
      }

   return false;
   }


/**
 * @brief Inserts a prefetch instruction at the given offset from a base register.
 *    Each successive prefetch instruction offsets its prefetch by one cache line
 *    (64 bytes) from the previous.
 *
 * @param[in] node : \c TR::Node associated with this prefetch
 * @param[in] numPrefetches : number of consecutive prefetch instructions to insert
 * @param[in] allocationReg : register containing the base address from which
 *               prefetches start
 * @param[in] offset : offset from \c allocationReg to begin prefetch
 * @param[in] cg : \c TR::CodeGenerator object
 */
static void insertAllocationPrefetch(
      TR::Node *node,
      int32_t numPrefetches,
      TR::Register *allocationReg,
      int32_t offset,
      TR::CodeGenerator *cg)
   {
   for (int32_t i=0; i<numPrefetches; i++)
      {
      generateMemInstruction(TR::InstOpCode::PREFETCHNTA, node,
         generateX86MemoryReference(allocationReg, offset, cg), cg);
      offset += 64;
      }
   }

// Generate code to allocate discontiguous arrays or objects and arrays when
// using a realtime GC policy from the object heap.  Returns the register
// containing the address of the allocation.
//
// If the sizeReg is non-null, the allocation is variable length.  In this case
// the elementSize is meaningful and "size" is the extra size to be added.
// Otherwise "size" contains the total size of the allocation.
//
// Also, on return the "segmentReg" register is set to the address of the
// memory segment.
//
static void genHeapAllocForDiscontiguousArraysOrRealtime(
      TR::Node *node,
      TR_OpaqueClassBlock *clazz,
      int32_t allocationSizeOrDataOffset,
      int32_t elementSize,
      TR::Register *sizeReg,
      TR::Register *eaxReal,
      TR::Register *segmentReg,
      TR::Register *tempReg,
      TR::LabelSymbol *failLabel,
      TR::CodeGenerator *cg)
   {

   // Load the current heap segment and see if there is room in it. Loop if
   // we can't get the lock on the segment.
   //
   TR::Compilation *comp = cg->comp();
   TR::Register *vmThreadReg = cg->getVMThreadRegister();
   bool generateArraylets = comp->generateArraylets();

   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());

   if (comp->getOptions()->realTimeGC())
      {
#if defined(J9VM_GC_REALTIME)
      // this will be bogus for variable length allocations because it only includes the header size (+ arraylet ptr for arrays)
      UDATA sizeClass = fej9->getObjectSizeClass(allocationSizeOrDataOffset);

      if (comp->getOption(TR_BreakOnNew))
         generateInstruction(TR::InstOpCode::INT3, node, cg);

      // heap allocation, so proceed
      if (sizeReg)
         {
         generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, eaxReal, eaxReal, cg);

         // make sure size isn't too big
         // convert max object size to num elements because computing an object size from num elements may overflow
         TR_ASSERT(fej9->getMaxObjectSizeForSizeClass() <= UINT_MAX, "assertion failure");
         generateRegImmInstruction(TR::InstOpCode::CMPRegImm4(), node, sizeReg, (fej9->getMaxObjectSizeForSizeClass()-allocationSizeOrDataOffset)/elementSize, cg);
         generateLabelInstruction(TR::InstOpCode::JA4, node, failLabel, cg);

         // Hybrid arraylets need a zero length test if the size is unknown.
         //
         if (!generateArraylets)
            {
            generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, sizeReg, sizeReg, cg);
            generateLabelInstruction(TR::InstOpCode::JE4, node, failLabel, cg);
            }

         // need to round up to sizeof(UDATA) so we can use it to index into size class index array
         // conservatively just add sizeof(UDATA) bytes and round
         int32_t round = 0;
         if (elementSize < sizeof(UDATA))
            round = sizeof(UDATA) - 1;

         // now compute size of object in bytes
         generateRegMemInstruction(TR::InstOpCode::LEARegMem(),
                                   node,
                                   segmentReg,
                                   generateX86MemoryReference(eaxReal,
                                                              sizeReg,
                                                              TR::MemoryReference::convertMultiplierToStride(elementSize),
                                                              allocationSizeOrDataOffset + round, cg), cg);


         if (elementSize < sizeof(UDATA))
            generateRegImmInstruction(TR::InstOpCode::ANDRegImms(), node, segmentReg, -(int32_t)sizeof(UDATA), cg);

#ifdef J9VM_INTERP_FLAGS_IN_CLASS_SLOT
         generateRegImmInstruction(TR::InstOpCode::CMPRegImm4(), node, segmentReg, J9_GC_MINIMUM_OBJECT_SIZE, cg);
         TR::LabelSymbol *doneLabel = generateLabelSymbol(cg);
         generateLabelInstruction(TR::InstOpCode::JAE4, node, doneLabel, cg);
         generateRegImmInstruction(TR::InstOpCode::MOVRegImm4(), node, segmentReg, J9_GC_MINIMUM_OBJECT_SIZE, cg);
         generateLabelInstruction(TR::InstOpCode::label, node, doneLabel, cg);
#endif

         // get size class
         generateRegMemInstruction(TR::InstOpCode::LRegMem(),
                                   node,
                                   tempReg,
                                   generateX86MemoryReference(vmThreadReg, fej9->thisThreadJavaVMOffset(), cg), cg);
         generateRegMemInstruction(TR::InstOpCode::LRegMem(),
                                   node,
                                   tempReg,
                                   generateX86MemoryReference(tempReg, fej9->getRealtimeSizeClassesOffset(), cg), cg);
         generateRegMemInstruction(TR::InstOpCode::LRegMem(),
                                   node,
                                   tempReg,
                                   generateX86MemoryReference(tempReg,
                                                              segmentReg, TR::MemoryReference::convertMultiplierToStride(1),
                                                              fej9->getSizeClassesIndexOffset(),
                                                              cg),
                                   cg);

         // tempReg now holds size class
         TR::MemoryReference *currentMemRef, *topMemRef, *currentMemRefBump;
         if (cg->comp()->target().is64Bit())
            {
            TR_ASSERT(sizeof(J9VMGCSegregatedAllocationCacheEntry) == 16, "unexpected J9VMGCSegregatedAllocationCacheEntry size");
            // going to play some games here
            //   need to use tempReg to index into two arrays:
            //        1) allocation caches
            //        2) cell size array
            //   The first one has stride 16, second one stride sizeof(UDATA)
            //   We need a shift instruction to be able to do stride 16
            //   To avoid two shifts, only do one for stride sizeof(UDATA) and use a multiplier in memory ref for 16
            //   64-bit, so shift 3 times for sizeof(UDATA) and use multiplier stride 2 in memory references
            generateRegImmInstruction(TR::InstOpCode::SHLRegImm1(), node, tempReg, 3, cg);
            currentMemRef =     generateX86MemoryReference(vmThreadReg, tempReg, TR::MemoryReference::convertMultiplierToStride(2), fej9->thisThreadAllocationCacheCurrentOffset(0), cg);
            topMemRef =         generateX86MemoryReference(vmThreadReg, tempReg, TR::MemoryReference::convertMultiplierToStride(2), fej9->thisThreadAllocationCacheTopOffset(0), cg);
            currentMemRefBump = generateX86MemoryReference(vmThreadReg, tempReg, TR::MemoryReference::convertMultiplierToStride(2), fej9->thisThreadAllocationCacheCurrentOffset(0), cg);
            }
         else
            {
            // size needs to be 8 or less or it there's no multiplier stride available (would need to use other branch of else)
            TR_ASSERT(sizeof(J9VMGCSegregatedAllocationCacheEntry) <= 8, "unexpected J9VMGCSegregatedAllocationCacheEntry size");

            currentMemRef =     generateX86MemoryReference(vmThreadReg, tempReg,
                                TR::MemoryReference::convertMultiplierToStride(sizeof(J9VMGCSegregatedAllocationCacheEntry)),
                                fej9->thisThreadAllocationCacheCurrentOffset(0), cg);
            topMemRef =         generateX86MemoryReference(vmThreadReg, tempReg,
                                TR::MemoryReference::convertMultiplierToStride(sizeof(J9VMGCSegregatedAllocationCacheEntry)),
                                fej9->thisThreadAllocationCacheTopOffset(0), cg);
            currentMemRefBump = generateX86MemoryReference(vmThreadReg, tempReg,
                                TR::MemoryReference::convertMultiplierToStride(sizeof(J9VMGCSegregatedAllocationCacheEntry)),
                                fej9->thisThreadAllocationCacheCurrentOffset(0), cg);
            }
         // tempReg now contains size class (32-bit) or size class * sizeof(J9VMGCSegregatedAllocationCacheEntry) (64-bit)

         // get next cell for this size class
         generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, eaxReal, currentMemRef, cg);

         // if null, then no cell available, use slow path
         generateRegMemInstruction(TR::InstOpCode::CMPRegMem(), node, eaxReal, topMemRef, cg);
         generateLabelInstruction(TR::InstOpCode::JAE4, node, failLabel, cg);

         // have a valid cell, need to update current cell pointer
         generateRegMemInstruction(TR::InstOpCode::LRegMem(),
                                   node,
                                   segmentReg,
                                   generateX86MemoryReference(vmThreadReg, fej9->thisThreadJavaVMOffset(), cg), cg);
         generateRegMemInstruction(TR::InstOpCode::LRegMem(),
                                   node,
                                   segmentReg,
                                   generateX86MemoryReference(segmentReg, fej9->getRealtimeSizeClassesOffset(), cg), cg);
         if (cg->comp()->target().is64Bit())
            {
            // tempReg already has already been shifted for sizeof(UDATA)
            generateRegMemInstruction(TR::InstOpCode::LRegMem(),
                                      node,
                                      segmentReg,
                                      generateX86MemoryReference(segmentReg,
                                                                 tempReg,
                                                                 TR::MemoryReference::convertMultiplierToStride(1),
                                                                 fej9->getSmallCellSizesOffset(),
                                                                 cg),
                                      cg);
            }
         else
            {
            // tempReg needs to be shifted for sizeof(UDATA)
            generateRegMemInstruction(TR::InstOpCode::LRegMem(),
                                   node,
                                   segmentReg,
                                   generateX86MemoryReference(segmentReg,
                                                              tempReg,
                                                              TR::MemoryReference::convertMultiplierToStride(sizeof(UDATA)),
                                                              fej9->getSmallCellSizesOffset(),
                                                              cg),
                                   cg);
            }
         // segmentReg now holds cell size

         // update current cell by cell size
         generateMemRegInstruction(TR::InstOpCode::ADDMemReg(), node, currentMemRefBump, segmentReg, cg);
         }
      else
         {
         generateRegMemInstruction(TR::InstOpCode::LRegMem(),
                                node,
                                eaxReal,
                                generateX86MemoryReference(vmThreadReg,
                                                           fej9->thisThreadAllocationCacheCurrentOffset(sizeClass),
                                                           cg),
                                cg);

         generateRegMemInstruction(TR::InstOpCode::CMPRegMem(),
                                node,
                                eaxReal,
                                generateX86MemoryReference(vmThreadReg,
                                                           fej9->thisThreadAllocationCacheTopOffset(sizeClass),
                                                           cg),
                                cg);

         generateLabelInstruction(TR::InstOpCode::JAE4, node, failLabel, cg);

         // we have an object in eaxReal, now bump the current updatepointer
         TR::InstOpCode::Mnemonic opcode;
         uint32_t cellSize = fej9->getCellSizeForSizeClass(sizeClass);
         if (cellSize <= 127)
            opcode = TR::InstOpCode::ADDMemImms();
         else if (cellSize == 128)
            {
            opcode = TR::InstOpCode::SUBMemImms();
            cellSize = (uint32_t)-128;
            }
         else
            opcode = TR::InstOpCode::ADDMemImm4();

         generateMemImmInstruction(opcode, node,
                                generateX86MemoryReference(vmThreadReg,
                                                           fej9->thisThreadAllocationCacheCurrentOffset(sizeClass),
                                                           cg),
                                cellSize, cg);
         }

      // we're done
      return;
#endif
      }
   else
      {
      bool isSmallAllocation = false;

      size_t heapAlloc_offset = offsetof(J9VMThread, heapAlloc);
      size_t heapTop_offset = offsetof(J9VMThread, heapTop);
      size_t tlhPrefetchFTA_offset = offsetof(J9VMThread, tlhPrefetchFTA);
#ifdef J9VM_GC_NON_ZERO_TLH
      if (!comp->getOption(TR_DisableDualTLH) && node->canSkipZeroInitialization())
         {
         heapAlloc_offset = offsetof(J9VMThread, nonZeroHeapAlloc);
         heapTop_offset = offsetof(J9VMThread, nonZeroHeapTop);
         tlhPrefetchFTA_offset = offsetof(J9VMThread, nonZeroTlhPrefetchFTA);
         }
#endif
      // Load the base of the next available heap storage.  This load is done speculatively on the assumption that the
      // allocation will be inlined.  If the assumption turns out to be false then the performance impact should be minimal
      // because the helper will be called in that case.  It is necessary to insert this load here so that it dominates all
      // control paths through this internal control flow region.
      //
      generateRegMemInstruction(TR::InstOpCode::LRegMem(),
                                node,
                                eaxReal,
                                generateX86MemoryReference(vmThreadReg,heapAlloc_offset, cg), cg);

      bool canSkipOverflowCheck = false;

      // If the array length is constant, check to see if the size of the array will fit in a single arraylet leaf.
      // If the allocation size is too large, call the snippet.
      //
      if (generateArraylets && (node->getOpCodeValue() == TR::anewarray || node->getOpCodeValue() == TR::newarray))
         {
         if (comp->getOption(TR_DisableTarokInlineArrayletAllocation))
            generateLabelInstruction(TR::InstOpCode::JMP4, node, failLabel, cg);

         if (sizeReg)
            {
            uint32_t maxContiguousArrayletLeafSizeInBytes =
               (uint32_t)(TR::Compiler->om.arrayletLeafSize() - TR::Compiler->om.sizeofReferenceAddress());

            int32_t maxArrayletSizeInElements = maxContiguousArrayletLeafSizeInBytes/elementSize;

            // Hybrid arraylets need a zero length test if the size is unknown.
            //
            generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, sizeReg, sizeReg, cg);
            generateLabelInstruction(TR::InstOpCode::JE4, node, failLabel, cg);

            generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, sizeReg, maxArrayletSizeInElements, cg);
            generateLabelInstruction(TR::InstOpCode::JAE4, node, failLabel, cg);

            // If the max arraylet leaf size is less than the amount of free space available on
            // the stack, there is no need to check for an overflow scenario.
            //
            if (maxContiguousArrayletLeafSizeInBytes <= cg->getMaxObjectSizeGuaranteedNotToOverflow() )
               canSkipOverflowCheck = true;
            }
         else if (TR::Compiler->om.isDiscontiguousArray(allocationSizeOrDataOffset))
            {
            // TODO: just call the helper directly and don't generate any
            //       further instructions.
            //
            // Actually, we should never get here because we've already checked
            // constant lengths for discontiguity...
            //
            generateLabelInstruction(TR::InstOpCode::JMP4, node, failLabel, cg);
            }
         }

      if (sizeReg && !canSkipOverflowCheck)
         {
         // Hybrid arraylets need a zero length test if the size is unknown.
         // The length could be zero.
         //
         if (!generateArraylets)
            {
            generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, sizeReg, sizeReg, cg);
            generateLabelInstruction(TR::InstOpCode::JE4, node, failLabel, cg);
            }

         // The GC will guarantee that at least 'maxObjectSizeGuaranteedNotToOverflow' bytes
         // of slush will exist between the top of the heap and the end of the address space.
         //
         uintptr_t maxObjectSize = cg->getMaxObjectSizeGuaranteedNotToOverflow();
         uintptr_t maxObjectSizeInElements = maxObjectSize / elementSize;

         if (cg->comp()->target().is64Bit() && !(maxObjectSizeInElements > 0 && maxObjectSizeInElements <= (uintptr_t)INT_MAX))
            {
            generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, tempReg, maxObjectSizeInElements, cg);
            generateRegRegInstruction(TR::InstOpCode::CMP8RegReg, node, sizeReg, tempReg, cg);
            }
         else
            {
            generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, sizeReg, (int32_t)maxObjectSizeInElements, cg);
            }

         // Must be an unsigned comparison on sizes.
         //
         generateLabelInstruction(TR::InstOpCode::JAE4, node, failLabel, cg);
         }

#if !defined(J9VM_GC_THREAD_LOCAL_HEAP)
      // Establish a loop label in case the new heap pointer cannot be committed.
      //
      TR::LabelSymbol *loopLabel = generateLabelSymbol(cg);
      generateLabelInstruction(TR::InstOpCode::label, node, loopLabel, cg);
#endif

      if (sizeReg)
         {
         // calculate variable size, rounding up if necessary to a intptr_t multiple boundary
         //
         int32_t round; // zero indicates no rounding is necessary

         if (!generateArraylets)
            {
//            TR_ASSERT(allocationSizeOrDataOffset % fej9->getObjectAlignmentInBytes() == 0, "Array header size of %d is not a multiple of %d", allocationSizeOrDataOffset, fej9->getObjectAlignmentInBytes());
            }


         round = (elementSize < TR::Compiler->om.getObjectAlignmentInBytes()) ? TR::Compiler->om.getObjectAlignmentInBytes() : 0;

         int32_t disp32 = round ? (round-1) : 0;
#ifdef J9VM_INTERP_FLAGS_IN_CLASS_SLOT
         if ( (node->getOpCodeValue() == TR::anewarray || node->getOpCodeValue() == TR::newarray))
            {
            // All arrays in combo builds will always be at least 12 bytes in size in all specs if
            // dual header shape is enabled and 20 bytes otherwise:
            //
            // Dual header shape is enabled:
            // 1)  class pointer + contig length + one or more elements
            // 2)  class pointer + 0 + 0 (for zero length arrays)
            //
            // Dual header shape is disabled:
            // 1)  class pointer + contig length + dataAddr + one or more elements
            // 2)  class pointer + 0 + 0 (for zero length arrays) + dataAddr
            //
            // Since objects are aligned to 8 bytes then the minimum size for an array must be 16 and 24 after rounding
            TR_ASSERT(J9_GC_MINIMUM_OBJECT_SIZE >= 8, "Expecting a minimum indexable object size >= 8 (actual minimum is %d)\n", J9_GC_MINIMUM_OBJECT_SIZE);

            generateRegMemInstruction(
               TR::InstOpCode::LEARegMem(),
               node,
               tempReg,
               generateX86MemoryReference(
                  eaxReal,
                  sizeReg,
                  TR::MemoryReference::convertMultiplierToStride(elementSize),
                  allocationSizeOrDataOffset+disp32, cg), cg);

            if (round)
               {
               generateRegImmInstruction(TR::InstOpCode::ANDRegImm4(), node, tempReg, -round, cg);
               }
            }
         else
#endif
            {
#ifdef J9VM_INTERP_FLAGS_IN_CLASS_SLOT
         generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, tempReg, tempReg, cg);
#endif


         generateRegMemInstruction(
                                   TR::InstOpCode::LEARegMem(),
                                   node,
                                   tempReg,
                                   generateX86MemoryReference(
#ifdef J9VM_INTERP_FLAGS_IN_CLASS_SLOT
                                                              tempReg,
#else
                                                              eaxReal,
#endif
                                                              sizeReg,
                                                              TR::MemoryReference::convertMultiplierToStride(elementSize),
                                                              allocationSizeOrDataOffset+disp32, cg), cg);

         if (round)
            {
            generateRegImmInstruction(TR::InstOpCode::ANDRegImm4(), node, tempReg, -round, cg);
            }

#ifdef J9VM_INTERP_FLAGS_IN_CLASS_SLOT
         generateRegImmInstruction(TR::InstOpCode::CMPRegImm4(), node, tempReg, J9_GC_MINIMUM_OBJECT_SIZE, cg);
         TR::LabelSymbol *doneLabel = generateLabelSymbol(cg);
         generateLabelInstruction(TR::InstOpCode::JAE4, node, doneLabel, cg);
         generateRegImmInstruction(TR::InstOpCode::MOVRegImm4(), node, tempReg, J9_GC_MINIMUM_OBJECT_SIZE, cg);
         generateLabelInstruction(TR::InstOpCode::label, node, doneLabel, cg);
         generateRegRegInstruction(TR::InstOpCode::ADDRegReg(), node, tempReg, eaxReal, cg);
#endif
            }
         }
      else
         {
         isSmallAllocation = allocationSizeOrDataOffset <= 0x40 ? true : false;
         allocationSizeOrDataOffset = (allocationSizeOrDataOffset+TR::Compiler->om.getObjectAlignmentInBytes()-1) & (-TR::Compiler->om.getObjectAlignmentInBytes());

         if ((uint32_t)allocationSizeOrDataOffset > cg->getMaxObjectSizeGuaranteedNotToOverflow())
            {
            generateRegRegInstruction(TR::InstOpCode::MOVRegReg(),  node, tempReg, eaxReal, cg);
            if (allocationSizeOrDataOffset <= 127)
               generateRegImmInstruction(TR::InstOpCode::ADDRegImms(), node, tempReg, allocationSizeOrDataOffset, cg);
            else if (allocationSizeOrDataOffset == 128)
               generateRegImmInstruction(TR::InstOpCode::SUBRegImms(), node, tempReg, (unsigned)-128, cg);
            else
               generateRegImmInstruction(TR::InstOpCode::ADDRegImm4(), node, tempReg, allocationSizeOrDataOffset, cg);

            // Check for overflow
            generateLabelInstruction(TR::InstOpCode::JB4, node, failLabel, cg);
            }
         else
            {
            generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, tempReg,
                                      generateX86MemoryReference(eaxReal, allocationSizeOrDataOffset, cg), cg);
            }
         }

      generateRegMemInstruction(TR::InstOpCode::CMPRegMem(),
                                node,
                                tempReg,
                                generateX86MemoryReference(vmThreadReg, heapTop_offset, cg), cg);

      generateLabelInstruction(TR::InstOpCode::JA4, node, failLabel, cg);

#if defined(J9VM_GC_THREAD_LOCAL_HEAP)

      // Make sure that the arraylet is aligned properly.
      //
      if (generateArraylets && (node->getOpCodeValue() == TR::anewarray || node->getOpCodeValue() == TR::newarray) )
         {
         generateRegMemInstruction(TR::InstOpCode::LEARegMem(),node,tempReg, generateX86MemoryReference(tempReg,TR::Compiler->om.getObjectAlignmentInBytes()-1,cg),cg);
         if (cg->comp()->target().is64Bit())
            generateRegImmInstruction(TR::InstOpCode::AND8RegImm4,node,tempReg,-TR::Compiler->om.getObjectAlignmentInBytes(),cg);
         else
            generateRegImmInstruction(TR::InstOpCode::AND4RegImm4,node,tempReg,-TR::Compiler->om.getObjectAlignmentInBytes(),cg);
         }

      generateMemRegInstruction(TR::InstOpCode::SMemReg(),
                                node,
                                generateX86MemoryReference(vmThreadReg, heapAlloc_offset, cg),
                                tempReg, cg);

      if (!isSmallAllocation && cg->enableTLHPrefetching())
         {
         TR::LabelSymbol *prefetchSnippetLabel = generateLabelSymbol(cg);
         TR::LabelSymbol *restartLabel = generateLabelSymbol(cg);
         cg->addSnippet(new (cg->trHeapMemory()) TR::X86AllocPrefetchSnippet(cg, node, TR::Options::_TLHPrefetchSize,
                                                                              restartLabel, prefetchSnippetLabel,
                                    (!comp->getOption(TR_DisableDualTLH) && node->canSkipZeroInitialization())));


         bool useDirectPrefetchCall = false;
         bool useSharedCodeCacheSnippet = fej9->supportsCodeCacheSnippets();

         // Generate the prefetch thunk in code cache.  Only generate this once.
         //
         bool prefetchThunkGenerated = (fej9->getAllocationPrefetchCodeSnippetAddress(comp) != 0);
#ifdef J9VM_GC_NON_ZERO_TLH
         if (!comp->getOption(TR_DisableDualTLH) && node->canSkipZeroInitialization())
            {
            prefetchThunkGenerated = (fej9->getAllocationNoZeroPrefetchCodeSnippetAddress(comp) !=0);
            }
#endif
         if (useSharedCodeCacheSnippet && prefetchThunkGenerated)
            {
            useDirectPrefetchCall = true;
            }

         generateRegRegInstruction(TR::InstOpCode::SUB4RegReg, node, tempReg, eaxReal, cg);

         generateMemRegInstruction(TR::InstOpCode::SUB4MemReg,
                                   node,
                                   generateX86MemoryReference(vmThreadReg, tlhPrefetchFTA_offset, cg),
                                   tempReg, cg);
         if (!useDirectPrefetchCall)
            generateLabelInstruction(TR::InstOpCode::JLE4, node, prefetchSnippetLabel, cg);
         else
            {
            generateLabelInstruction(TR::InstOpCode::JG4, node, restartLabel, cg);
            TR::SymbolReference * helperSymRef = cg->getSymRefTab()->findOrCreateRuntimeHelper(TR_X86CodeCachePrefetchHelper);
            TR::MethodSymbol *helperSymbol = helperSymRef->getSymbol()->castToMethodSymbol();
#ifdef J9VM_GC_NON_ZERO_TLH
            if (!comp->getOption(TR_DisableDualTLH) && node->canSkipZeroInitialization())
               {
               helperSymbol->setMethodAddress(fej9->getAllocationNoZeroPrefetchCodeSnippetAddress(comp));
               }
            else
               {
               helperSymbol->setMethodAddress(fej9->getAllocationPrefetchCodeSnippetAddress(comp));
               }
#else
            helperSymbol->setMethodAddress(fej9->getAllocationPrefetchCodeSnippetAddress(comp));
#endif
            generateImmSymInstruction(TR::InstOpCode::CALLImm4, node, (uintptr_t)helperSymbol->getMethodAddress(), helperSymRef, cg);
            }

         generateLabelInstruction(TR::InstOpCode::label, node, restartLabel, cg);
         }

#else // J9VM_GC_THREAD_LOCAL_HEAP
      generateMemRegInstruction(TR::InstOpCode::CMPXCHGMemReg(), node, generateX86MemoryReference(vmThreadReg, heapAlloc_offset, cg), tempReg, cg);
      generateLabelInstruction(TR::InstOpCode::JNE4, node, loopLabel, cg);
#endif // !J9VM_GC_THREAD_LOCAL_HEAP
      }
   }

// ------------------------------------------------------------------------------
// genHeapAllocForObjectOrHybridArraylet
//
// Needs 2TLH support.
// ------------------------------------------------------------------------------

/**
 * @param[in] eaxReal : address of the newly allocated object
 * @param[in] nextTLHAllocReg : the new TLH alloc pointer after the object is allocated
 */

static void genHeapAllocForObjectOrHybridArraylet(
      TR::Node *node,
      TR_OpaqueClassBlock *clazz,
      int32_t allocationSizeOrDataOffset,
      int32_t elementSize,
      TR::Register *sizeReg,
      TR::Register *eaxReal,
      TR::Register *nextTLHAllocReg,
      TR::Register *tempReg,
      TR::LabelSymbol *failLabel,
      TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR::Register *vmThreadReg = cg->getVMThreadRegister();

   TR_ASSERT_FATAL(!comp->generateArraylets(), "This function can only handle hybrid arraylets");

   bool isTooSmallToPrefetch = false;

   if (sizeReg)
      {
      // -------------
      // VARIABLE SIZE
      // -------------

      // The GC will guarantee that at least 'maxObjectSizeGuaranteedNotToOverflow' bytes
      // of slush will exist between the top of the heap and the end of the address space.
      //
      uintptr_t maxObjectSize = cg->getMaxObjectSizeGuaranteedNotToOverflow();
      uintptr_t maxObjectSizeInElements = maxObjectSize / elementSize;

      if (comp->target().is64Bit() && !(maxObjectSizeInElements > 0 && maxObjectSizeInElements <= (uintptr_t)INT_MAX))
         {
         // nextTLHAllocReg can be used as a scratch register until it is defined below
         //
         generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, nextTLHAllocReg, maxObjectSizeInElements, cg);
         generateRegRegInstruction(TR::InstOpCode::CMP8RegReg, node, sizeReg, nextTLHAllocReg, cg);
         }
      else
         {
         generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, sizeReg, (int32_t)maxObjectSizeInElements, cg);
         }

      // Must be an unsigned comparison on sizes.
      //
      generateLabelInstruction(TR::InstOpCode::JAE4, node, failLabel, cg);

      generateRegMemInstruction(TR::InstOpCode::LRegMem(),
                                node,
                                eaxReal,
                                generateX86MemoryReference(vmThreadReg,
                                                           offsetof(J9VMThread, heapAlloc), cg), cg);

      generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, nextTLHAllocReg, sizeReg, cg);

      // Artificially adjust the number of elements by 1 if the array is zero length.  This works
      // because either the array is zero length and needs a discontiguous array length field
      // (occupying a slot) or it has at least 1 element which will take up a slot anyway.
      //
      // Native 64-bit array headers do not need this adjustment because the
      // contiguous and discontiguous array headers are the same size.
      //
      if (comp->target().is32Bit() || (comp->target().is64Bit() && comp->useCompressedPointers()))
         {
         generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, nextTLHAllocReg, 1, cg);
         generateRegImmInstruction(TR::InstOpCode::ADC4RegImm4, node, nextTLHAllocReg, 0, cg);
         }

      uint8_t shiftVal = TR::MemoryReference::convertMultiplierToStride(elementSize);
      if (shiftVal > 0)
         {
         generateRegImmInstruction(TR::InstOpCode::SHLRegImm1(), node, nextTLHAllocReg, shiftVal, cg);
         }

      // calculate variable size, rounding up if necessary to a intptr_t multiple boundary
      //
      // zero round indicates no rounding is necessary
      //
      int32_t round =
         (elementSize >= TR::Compiler->om.getObjectAlignmentInBytes()) ?
            0 :
            TR::Compiler->om.getObjectAlignmentInBytes();
      int32_t disp32 = round ? (round-1) : 0;

      generateRegImmInstruction(TR::InstOpCode::ADDRegImm4(), node, nextTLHAllocReg, allocationSizeOrDataOffset+disp32, cg);

      if (round)
         {
         generateRegImmInstruction(TR::InstOpCode::ANDRegImm4(), node, nextTLHAllocReg, -round, cg);
         }

      // Copy full object size in bytes to RCX for zero init via REP TR::InstOpCode::STOSQ
      //
      generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, tempReg, nextTLHAllocReg, cg);

      generateRegRegInstruction(TR::InstOpCode::ADDRegReg(), node, nextTLHAllocReg, eaxReal, cg);
      }
   else
      {
      // ----------
      // FIXED SIZE
      // ----------

      generateRegMemInstruction(TR::InstOpCode::LRegMem(),
                                node,
                                eaxReal,
                                generateX86MemoryReference(vmThreadReg,
                                                           offsetof(J9VMThread, heapAlloc), cg), cg);

      if (comp->getOptLevel() < hot)
         isTooSmallToPrefetch = allocationSizeOrDataOffset <= 0x40 ? true : false;

      allocationSizeOrDataOffset = (allocationSizeOrDataOffset+TR::Compiler->om.getObjectAlignmentInBytes()-1) & (-TR::Compiler->om.getObjectAlignmentInBytes());

      if ((uint32_t)allocationSizeOrDataOffset > cg->getMaxObjectSizeGuaranteedNotToOverflow())
         {
         generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, nextTLHAllocReg, eaxReal, cg);
         if (allocationSizeOrDataOffset <= 127)
            generateRegImmInstruction(TR::InstOpCode::ADDRegImms(), node, nextTLHAllocReg, allocationSizeOrDataOffset, cg);
         else if (allocationSizeOrDataOffset == 128)
            generateRegImmInstruction(TR::InstOpCode::SUBRegImms(), node, nextTLHAllocReg, (unsigned)-128, cg);
         else
            generateRegImmInstruction(TR::InstOpCode::ADDRegImm4(), node, nextTLHAllocReg, allocationSizeOrDataOffset, cg);

         // Check for overflow
         generateLabelInstruction(TR::InstOpCode::JB4, node, failLabel, cg);
         }
      else
         {
         generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, nextTLHAllocReg,
                                   generateX86MemoryReference(eaxReal, allocationSizeOrDataOffset, cg), cg);
         }
      }

   // -----------
   // MERGED PATH
   // -----------

   generateRegMemInstruction(TR::InstOpCode::CMPRegMem(),
                             node,
                             nextTLHAllocReg,
                             generateX86MemoryReference(vmThreadReg, offsetof(J9VMThread, heapTop), cg), cg);

   generateLabelInstruction(TR::InstOpCode::JA4, node, failLabel, cg);

   if (!isTooSmallToPrefetch && cg->enableTLHPrefetching())
      {
      insertAllocationPrefetch(node, 1, nextTLHAllocReg, 0xc0, cg);
      }

   generateMemRegInstruction(TR::InstOpCode::SMemReg(),
                             node,
                             generateX86MemoryReference(vmThreadReg, offsetof(J9VMThread, heapAlloc), cg),
                             nextTLHAllocReg, cg);

   if (!isTooSmallToPrefetch && node->getOpCodeValue() != TR::New && cg->enableTLHPrefetching())
      {
      insertAllocationPrefetch(node, 3, nextTLHAllocReg, 0x100, cg);
      }
   }

// Generate the code to initialize an object header - used for both new and
// array new
//
static void genInitObjectHeader(TR::Node             *node,
                                TR_OpaqueClassBlock *clazz,
                                TR::Register         *classReg,
                                TR::Register         *objectReg,
                                TR::Register         *tempReg,
                                bool                 isZeroInitialized,
                                bool                 isDynamicAllocation,
                                TR::CodeGenerator    *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());

   bool use64BitClasses = comp->target().is64Bit() &&
                           (!TR::Compiler->om.generateCompressedObjectHeaders() ||
                            (comp->compileRelocatableCode() && comp->getOption(TR_UseSymbolValidationManager)));

   TR_ASSERT((isDynamicAllocation || clazz), "Cannot have a null clazz while not doing dynamic array allocation\n");

   // --------------------------------------------------------------------------------
   //
   // Initialize CLASS field
   //
   // --------------------------------------------------------------------------------
   //
   TR::InstOpCode::Mnemonic opSMemReg = TR::InstOpCode::SMemReg(use64BitClasses);

   TR::Register * clzReg = classReg;

   // For dynamic array allocation, load the array class from the component class and store into clzReg
   if (isDynamicAllocation)
      {
      TR_ASSERT((node->getOpCodeValue() == TR::anewarray), "Dynamic allocation currently only supports reference arrays");
      TR_ASSERT(classReg, "must have a classReg for dynamic allocation");
      clzReg = tempReg;
      generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, clzReg, generateX86MemoryReference(classReg, offsetof(J9Class, arrayClass), cg), cg);
      }
   // TODO: should be able to use a TR_ClassPointer relocation without this stuff (along with class validation)
   else if (cg->needClassAndMethodPointerRelocations() && !comp->getOption(TR_UseSymbolValidationManager))
      {
      TR::Register *vmThreadReg = cg->getVMThreadRegister();
      if (node->getOpCodeValue() == TR::newarray)
         {
         generateRegMemInstruction(TR::InstOpCode::LRegMem(), node,tempReg,
             generateX86MemoryReference(vmThreadReg,offsetof(J9VMThread, javaVM), cg), cg);
         generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, tempReg,
             generateX86MemoryReference(tempReg,
             offsetof(J9JavaVM, booleanArrayClass)+(node->getSecondChild()->getInt()-4)*sizeof(J9Class*), cg), cg);
         // tempReg should contain a 32 bit pointer.
         generateMemRegInstruction(opSMemReg, node,
             generateX86MemoryReference(objectReg, TR::Compiler->om.offsetOfObjectVftField(), cg),
             tempReg, cg);
         clzReg = tempReg;
         }
      else
         {
         TR_ASSERT_FATAL((node->getOpCodeValue() == TR::New)
                   && classReg, "Must have a classReg for TR::New in non-SVM AOT mode");
         clzReg = classReg;
         }
      }


   // For RealTime Code Only.
   int32_t orFlags = 0;
   int32_t orFlagsClass = 0;

   if (!clzReg)
      {
      TR::Instruction *instr = NULL;
      if (use64BitClasses)
         {
         if (cg->needClassAndMethodPointerRelocations() && comp->getOption(TR_UseSymbolValidationManager))
            instr = generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, tempReg, ((intptr_t)clazz|orFlagsClass), cg, TR_ClassPointer);
         else
            instr = generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, tempReg, ((intptr_t)clazz|orFlagsClass), cg);
         generateMemRegInstruction(TR::InstOpCode::S8MemReg, node, generateX86MemoryReference(objectReg, TR::Compiler->om.offsetOfObjectVftField(), cg), tempReg, cg);
         }
      else
         {
         instr = generateMemImmInstruction(TR::InstOpCode::S4MemImm4, node, generateX86MemoryReference(objectReg, TR::Compiler->om.offsetOfObjectVftField(), cg), (int32_t)((uintptr_t)clazz|orFlagsClass), cg);
         }
      }
   else
      {
      if (orFlagsClass != 0)
         generateRegImmInstruction(use64BitClasses ? TR::InstOpCode::OR8RegImm4 : TR::InstOpCode::OR4RegImm4,  node, clzReg, orFlagsClass, cg);
      generateMemRegInstruction(opSMemReg, node,
          generateX86MemoryReference(objectReg, TR::Compiler->om.offsetOfObjectVftField(), cg), clzReg, cg);
      }

   // --------------------------------------------------------------------------------
   //
   // Initialize FLAGS field
   //
   // --------------------------------------------------------------------------------
   //

   // Collect the flags to be OR'd in that are known at compile time.
   //

#ifndef J9VM_INTERP_FLAGS_IN_CLASS_SLOT
   // Enable macro once GC-Helper is fixed
   J9ROMClass *romClass = TR::Compiler->cls.romClassOf(clazz);
   if (romClass)
      {
      orFlags |= romClass->instanceShape;
      orFlags |= fej9->getStaticObjectFlags();

#if defined(J9VM_OPT_NEW_OBJECT_HASH)
      // put orFlags or 0 into header if needed
      generateMemImmInstruction(TR::InstOpCode::S4MemImm4, node,
                                generateX86MemoryReference(objectReg, TMP_OFFSETOF_J9OBJECT_FLAGS, cg),
                                orFlags, cg);

#endif /* !J9VM_OPT_NEW_OBJECT_HASH */
      }
#endif /* FLAGS_IN_CLASS_SLOT */

   // --------------------------------------------------------------------------------
   //
   // Initialize MONITOR field
   //
   // --------------------------------------------------------------------------------
   //
   // For dynamic array allocation, in case (very unlikely) the object array has a lock word, we just initialized it to 0 conservatively.
   // In this case, if the original array is reserved, initializing the cloned object's lock word to 0 will force the
   // locking to go to the slow locking path.
   if (isDynamicAllocation)
      {
      TR::LabelSymbol *doneLabel = generateLabelSymbol(cg);
      generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, tempReg, generateX86MemoryReference(clzReg, offsetof(J9ArrayClass, lockOffset), cg), cg);
      generateRegImmInstruction(TR::InstOpCode::CMPRegImm4(), node, tempReg, (int32_t)-1, cg);
      generateLabelInstruction (TR::InstOpCode::JE4, node, doneLabel, cg);
      generateMemImmInstruction(TR::InstOpCode::SMemImm4(comp->target().is64Bit() && !fej9->generateCompressedLockWord()),
            node, generateX86MemoryReference(objectReg, tempReg, 0, cg), 0, cg);
      generateLabelInstruction(TR::InstOpCode::label, node, doneLabel, cg);
      }
   else
      {
      bool initReservable = TR::Compiler->cls.classFlagReservableWordInitValue(clazz);
      if (!isZeroInitialized || initReservable)
         {
         bool initLw = (node->getOpCodeValue() != TR::New) || initReservable;
         int lwOffset = fej9->getByteOffsetToLockword(clazz);
         if (lwOffset == -1)
            initLw = false;

         if (initLw)
            {
            int32_t initialLwValue = 0;
            if (initReservable)
               initialLwValue = OBJECT_HEADER_LOCK_RESERVED;

            generateMemImmInstruction(TR::InstOpCode::SMemImm4(comp->target().is64Bit() && !fej9->generateCompressedLockWord()),
                  node, generateX86MemoryReference(objectReg, lwOffset, cg), initialLwValue, cg);
            }
         }
      }
   }


// Generate the code to initialize an array object header
//
static void genInitArrayHeader(
      TR::Node *node,
      TR_OpaqueClassBlock *clazz,
      TR::Register *classReg,
      TR::Register *objectReg,
      TR::Register *sizeReg,
      int32_t elementSize,
      int32_t arrayletDataOffset,
      TR::Register *tempReg,
      bool isZeroInitialized,
      bool isDynamicAllocation,
      bool shouldInitZeroSizedArrayHeader,
      TR::CodeGenerator *cg)
   {
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());

   // Initialize the object header
   //
   genInitObjectHeader(node, clazz, classReg, objectReg, tempReg, isZeroInitialized, isDynamicAllocation, cg);

   int32_t arraySizeOffset = fej9->getOffsetOfContiguousArraySizeField();

   TR::MemoryReference *arraySizeMR = generateX86MemoryReference(objectReg, arraySizeOffset, cg);
   // Special handling of zero sized arrays.
   // Zero length arrays are discontiguous (i.e. they also need the discontiguous length field to be 0) because
   // they are indistinguishable from non-zero length discontiguous arrays. But instead of explicitly checking
   // for zero sized arrays we unconditionally store 0 in the third dword of the array object header. That is
   // safe because the 3rd dword is either array size of a zero sized array or will contain the first elements
   // of an array:
   // - When dual header shape is enabled zero sized arrays have the following layout:
   // - The smallest array possible is a byte array with 1 element which would have a layout:
   //   #bits per section (compressed refs): | 32 bits |  32 bits   | 32 bits | 32 bits |   32 bits   |   32 bits    |
   //   zero sized arrays:                   |  class  | mustBeZero |  size   | padding |            other           |
   //   smallest contiguous array:           |  class  |    size    | padding |           other                      |
   //
   // - When dual header shape is disabled zero sized arrays have the following layout:
   //   #bits per section (compressed refs): | 32 bits |  32 bits   | 32 bits | 32 bits |   32 bits   |   32 bits    |
   //   zero sized arrays:                   |  class  | mustBeZero |  size   | padding |          dataAddr          |
   //   smallest contiguous array:           |  class  |    size    |      dataAddr     | 1 byte + padding |  other  |
   //
   // Refer to J9IndexableObject(Dis)contiguousCompressed structs runtime/oti/j9nonbuilder.h for more detail
   int32_t arrayDiscontiguousSizeOffset = fej9->getOffsetOfDiscontiguousArraySizeField();
   TR::MemoryReference *arrayDiscontiguousSizeMR = generateX86MemoryReference(objectReg, arrayDiscontiguousSizeOffset, cg);

   TR::Compilation *comp = cg->comp();

   bool canUseFastInlineAllocation =
      (!comp->getOptions()->realTimeGC() &&
       !comp->generateArraylets()) ? true : false;

   // Initialize the array size
   //
   if (sizeReg)
      {
      // Variable size
      //
      if (canUseFastInlineAllocation)
         {
         // Native 64-bit needs to cover the discontiguous size field
         //
         TR::InstOpCode::Mnemonic storeOp = (comp->target().is64Bit() && !comp->useCompressedPointers()) ? TR::InstOpCode::S8MemReg : TR::InstOpCode::S4MemReg;
         generateMemRegInstruction(storeOp, node, arraySizeMR, sizeReg, cg);
         }
      else
         {
         generateMemRegInstruction(TR::InstOpCode::S4MemReg, node, arraySizeMR, sizeReg, cg);
         }
      // Take care of zero sized arrays as they are discontiguous and not contiguous
      if (shouldInitZeroSizedArrayHeader)
         {
         generateMemImmInstruction(TR::InstOpCode::S4MemImm4, node, arrayDiscontiguousSizeMR, 0, cg);
         }
      }
   else
      {
      // Fixed size
      //
      int32_t instanceSize = 0;
      if (canUseFastInlineAllocation)
         {
         // Native 64-bit needs to cover the discontiguous size field
         //
         TR::InstOpCode::Mnemonic storeOp = (comp->target().is64Bit() && !comp->useCompressedPointers()) ? TR::InstOpCode::S8MemImm4 : TR::InstOpCode::S4MemImm4;
         instanceSize = node->getFirstChild()->getInt();
         generateMemImmInstruction(storeOp, node, arraySizeMR, instanceSize, cg);
         }
      else
         {
         instanceSize = node->getFirstChild()->getInt();
         generateMemImmInstruction(TR::InstOpCode::S4MemImm4, node, arraySizeMR, instanceSize, cg);
         }
      // Take care of zero sized arrays as they are discontiguous and not contiguous
      if (shouldInitZeroSizedArrayHeader && (instanceSize == 0))
         {
         generateMemImmInstruction(TR::InstOpCode::S4MemImm4, node, arrayDiscontiguousSizeMR, 0, cg);
         }
      }

   bool generateArraylets = comp->generateArraylets();

   if (generateArraylets)
      {
      // write arraylet pointer
      TR::InstOpCode::Mnemonic storeOp;

      generateRegMemInstruction(
         TR::InstOpCode::LEARegMem(), node,
         tempReg,
         generateX86MemoryReference(objectReg, arrayletDataOffset, cg), cg);

      if (comp->useCompressedPointers())
         {
         storeOp = TR::InstOpCode::S4MemReg;

         // Compress the arraylet pointer.
         //
         if (TR::Compiler->om.compressedReferenceShiftOffset() > 0)
            generateRegImmInstruction(TR::InstOpCode::SHR8RegImm1, node, tempReg, TR::Compiler->om.compressedReferenceShiftOffset(), cg);
         }
      else
         {
         storeOp = TR::InstOpCode::SMemReg();
         }

      TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());
      generateMemRegInstruction(storeOp, node, generateX86MemoryReference(objectReg, fej9->getFirstArrayletPointerOffset(comp), cg), tempReg, cg);
      }

   }


// ------------------------------------------------------------------------------
// genZeroInitForEntireObjectOrHybridArraylet
// ------------------------------------------------------------------------------

static bool genZeroInitForEntireObjectOrHybridArraylet(
      TR::Node *node,
      int32_t objectSizeInBytes,
      int32_t elementSize,
      TR::Register *sizeReg,
      TR::Register *newObjectAddressReg,
      TR::Register *numBytesToZeroInitReg,
      TR::Register *segmentReg,
      TR_X86ScratchRegisterManager *srm,
      TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();

   bool isArrayNew = (node->getOpCodeValue() != TR::New);
   auto headerSizeInBytes = isArrayNew ?
      TR::Compiler->om.contiguousArrayHeaderSizeInBytes() :
      TR::Compiler->om.objectHeaderSizeInBytes();

   // In order for us to successfully initialize the size field of a zero sized array
   // we must set headerSizeInBytes to 8 bytes for compressed refs and 12 bytes for full refs.
   // This can be accomplished by using offset of discontiguous array size field.
   // However, when dealing with compressed refs with dual header shape enabled we don't
   // need to change the headerSizeInBytes because contiguous header size is equal to the offset
   // of discontiguous array size field.
   // This allows rep stosb to initialize the size field of zero sized arrays appropriately.
   //
   // Refer to J9IndexableObject(Dis)contiguousCompressed structs in runtime/oti/j9nonbuilder.h for more detail
   //
   if (!comp->target().is32Bit() && isArrayNew
         && (TR::Compiler->om.isIndexableDataAddrPresent() || !TR::Compiler->om.compressObjectReferences()))
      {
      TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());

      TR_ASSERT_FATAL_WITH_NODE(node,
         (fej9->getOffsetOfDiscontiguousArraySizeField() - fej9->getOffsetOfContiguousArraySizeField()) == 4,
         "Offset of size field in discontiguous array header is expected to be 4 bytes more than contiguous array header. "
         "But size field offset for contiguous array header was %d bytes and %d bytes for discontiguous array header.\n",
         fej9->getOffsetOfContiguousArraySizeField(), fej9->getOffsetOfDiscontiguousArraySizeField());

      headerSizeInBytes = static_cast<uint32_t>(fej9->getOffsetOfDiscontiguousArraySizeField());
      }

   TR_ASSERT(headerSizeInBytes >= 4, "Object/Array header must be >= 4.");
   objectSizeInBytes -= headerSizeInBytes;

   if (!minRepstosdWords)
      {
      static char *p= feGetEnv("TR_MinRepstosdWords");
      minRepstosdWords = p ? atoi(p) : MIN_REPSTOSD_WORDS;
      }

   if (sizeReg || objectSizeInBytes >= minRepstosdWords)
      {
      // Zero-initialize by using REP TR::InstOpCode::STOSB.
      //
      if (sizeReg)
         {
         // -------------
         // VARIABLE SIZE
         // -------------

         // Subtract off the header size and initialize the remaining slots.
         //
         // When the size is in a register, the numBytesToZeroInitReg contains the
         // rounded object size including the header
         //
         generateRegImmInstruction(TR::InstOpCode::SUBRegImms(), node, numBytesToZeroInitReg, headerSizeInBytes, cg);
         }
      else
         {
         // ----------
         // FIXED SIZE
         // ----------

         if (comp->target().is64Bit() && !IS_32BIT_SIGNED(objectSizeInBytes))
            {
            generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, numBytesToZeroInitReg, objectSizeInBytes, cg);
            }
         else
            {
            generateRegImmInstruction(TR::InstOpCode::MOVRegImm4(), node, numBytesToZeroInitReg, objectSizeInBytes, cg);
            }
         }

      // If the compile-time size is unknown, generate a runtime length check to
      // determine if REP STOS initialization is more appropriate.
      //
      // On 32-bit, always do REP STOS initialization inline.
      //
      static const char *p = feGetEnv("TR_repStosZeroInitThresholdBytes");
      static int32_t repStosZeroInitThresholdBytes = p ? atoi(p) : 64;
      static bool doInlineRepStosZeroInit = feGetEnv("TR_dontInlineRepStosZeroInit") ? false : true;

      TR::Register *zeroInitScratchReg = NULL;
      if (comp->target().is64Bit())
         {
         zeroInitScratchReg = srm->findOrCreateScratchRegister();
         }

#ifdef TR_TARGET_64BIT
      if (sizeReg && doInlineRepStosZeroInit)
         {
         int32_t repSTOSThresholdAdjustment = 0;
         int32_t startingAddressAdjustment = 0;

         /**
          * When initialization will be done inline with 8-byte stores, if the object
          * header is not a multiple of 8 then adjust the starting address back by
          * four bytes to ensure the stores are aligned on their natural boundary
          * and so that initialization does not run past the end of the newly allocated
          * object.  The REP STOS threshold will also need to be adjusted to account
          * for these four bytes.
          */
         if (headerSizeInBytes % 16 == 12)
            {
            repSTOSThresholdAdjustment = -4;
            startingAddressAdjustment = -4;
            }

         TR::LabelSymbol *repStosInitLabelSym = generateLabelSymbol(cg);
         TR::LabelSymbol *mergeInitLabelSym = generateLabelSymbol(cg);

         generateRegImmInstruction(
            TR::InstOpCode::CMPRegImms(),
            node,
            numBytesToZeroInitReg,
            repStosZeroInitThresholdBytes + repSTOSThresholdAdjustment,
            cg);
         generateLabelInstruction(TR::InstOpCode::JG4, node, repStosInitLabelSym, cg);

         // Begin zero initialization after the header, adjusting for header size
         // if necessary
         //
         generateRegMemInstruction(
            TR::InstOpCode::LEARegMem(),
            node,
            segmentReg,
            generateX86MemoryReference(newObjectAddressReg, headerSizeInBytes + startingAddressAdjustment, cg),
            cg);

         generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, zeroInitScratchReg, zeroInitScratchReg, cg);

         // Generate mainline zero initialization with stores
         //
         TR::LabelSymbol *zeroInitLoopLabelSym = generateLabelSymbol(cg);
         generateLabelInstruction(TR::InstOpCode::label, node, zeroInitLoopLabelSym, cg);
         generateMemRegInstruction(TR::InstOpCode::S8MemReg, node,
            generateX86MemoryReference(segmentReg, 0, cg),
            zeroInitScratchReg, cg);
         generateRegImmInstruction(TR::InstOpCode::ADD8RegImms, node, segmentReg, 8, cg);
         generateRegImmInstruction(TR::InstOpCode::SUB8RegImms, node, numBytesToZeroInitReg, 8, cg);
         generateLabelInstruction(TR::InstOpCode::JG4, node, zeroInitLoopLabelSym, cg);

         {
         // Generate out-of-line REP STOS initialization
         //
         TR_OutlinedInstructionsGenerator og(repStosInitLabelSym, node, cg);

         // newObjectAddressReg must be in rax
         // segmentReg must be in rdi
         // numBytesToZeroInitReg must be in rcx

         // Begin zero initialization after the header
         //
         generateRegMemInstruction(
            TR::InstOpCode::LEARegMem(),
            node,
            segmentReg,
            generateX86MemoryReference(newObjectAddressReg, headerSizeInBytes, cg),
            cg);

         generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, zeroInitScratchReg, newObjectAddressReg, cg);
         generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, newObjectAddressReg, newObjectAddressReg, cg);
         generateInstruction(TR::InstOpCode::REPSTOSB, node, cg);
         generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, newObjectAddressReg, zeroInitScratchReg, cg);
         generateLabelInstruction(TR::InstOpCode::JMP4, node, mergeInitLabelSym, cg);
         og.endOutlinedInstructionSequence();
         }

         srm->reclaimScratchRegister(zeroInitScratchReg);

         // Merge
         //
         generateLabelInstruction(TR::InstOpCode::label, node, mergeInitLabelSym, cg);
         }
      else
         {
#endif
         // Begin zero initialization after the header
         //
         generateRegMemInstruction(
            TR::InstOpCode::LEARegMem(),
            node,
            segmentReg,
            generateX86MemoryReference(newObjectAddressReg, headerSizeInBytes, cg),
            cg);

         if (comp->target().is64Bit())
            {
            generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, zeroInitScratchReg, newObjectAddressReg, cg);
            }
         else
            {
            generateRegInstruction(TR::InstOpCode::PUSHReg, node, newObjectAddressReg, cg);
            }
         generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, newObjectAddressReg, newObjectAddressReg, cg);
         generateInstruction(TR::InstOpCode::REPSTOSB, node, cg);
         if (comp->target().is64Bit())
            {
            generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, newObjectAddressReg, zeroInitScratchReg, cg);
            srm->reclaimScratchRegister(zeroInitScratchReg);
            }
         else
            {
            generateRegInstruction(TR::InstOpCode::POPReg, node, newObjectAddressReg, cg);
            }
#ifdef TR_TARGET_64BIT
         }
#endif

      return true;
      }
   else if (objectSizeInBytes > 0)
      {
      if (objectSizeInBytes % 16 == 12)
         {
         // Zero-out header to avoid a 12-byte residue
         objectSizeInBytes += 4;
         headerSizeInBytes -= 4;
         }

      TR::Register *scratchReg = srm->findOrCreateScratchRegister(TR_FPR);
      generateRegRegInstruction(TR::InstOpCode::PXORRegReg, node, scratchReg, scratchReg, cg);
      int32_t offset = 0;
      while (objectSizeInBytes >= 16)
         {
         generateMemRegInstruction(TR::InstOpCode::MOVDQUMemReg, node, generateX86MemoryReference(newObjectAddressReg, headerSizeInBytes + offset, cg), scratchReg, cg);
         objectSizeInBytes -= 16;
         offset += 16;
         }

      switch (objectSizeInBytes)
         {
         case 8:
            generateMemRegInstruction(TR::InstOpCode::MOVQMemReg, node, generateX86MemoryReference(newObjectAddressReg, headerSizeInBytes + offset, cg), scratchReg, cg);
            break;
         case 4:
            generateMemRegInstruction(TR::InstOpCode::MOVDMemReg, node, generateX86MemoryReference(newObjectAddressReg, headerSizeInBytes + offset, cg), scratchReg, cg);
            break;
         case 0:
            break;
         default:
            TR_ASSERT(false, "residue size should only be 0, 4 or 8.");
         }

      srm->reclaimScratchRegister(scratchReg);
      return false;
      }
   else
      {
      return false;
      }
   }


// Generate the code to initialize the data portion of an allocated object.
// Zero-initialize the monitor slot in the header at the same time.
// If "sizeReg"  is non-null it contains the number of array elements and
// "elementSize" contains the size of each element.
// Otherwise the object size is in "objectSize".
//
static bool genZeroInitEntireObject(
      TR::Node *node,
      int32_t objectSize,
      int32_t elementSize,
      TR::Register *sizeReg,
      TR::Register *targetReg,
      TR::Register *tempReg,
      TR::Register *segmentReg,
      TR_X86ScratchRegisterManager *srm,
      TR::CodeGenerator *cg)
   {
   // object header flags now occupy 4bytes on 64-bit
   TR::ILOpCodes opcode = node->getOpCodeValue();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());
   TR::Compilation *comp = cg->comp();

   bool isArrayNew = (opcode != TR::New) ;
   TR_OpaqueClassBlock *clazz = NULL;

   // set up clazz value here
   comp->canAllocateInline(node, clazz);

   int32_t numSlots = 0;
   int32_t startOfZeroInits = isArrayNew ? TR::Compiler->om.contiguousArrayHeaderSizeInBytes() : TR::Compiler->om.objectHeaderSizeInBytes();

   if (comp->target().is64Bit())
      {
      // round down to the nearest word size
      TR_ASSERT(startOfZeroInits < 0xF8, "expecting start of zero inits to be the size of the header");
      startOfZeroInits &= 0xF8;
      }

   numSlots = (int32_t)((objectSize - startOfZeroInits)/TR::Compiler->om.sizeofReferenceAddress());

   bool generateArraylets = comp->generateArraylets();

   int32_t i;


   // *** old object header ***
   // since i'm always confused,
   // here is the layout of an object
   //
   // #if defined(J9VM_THR_LOCK_NURSERY)
   //
   // on 32-bit
   //     for an indexable object [header = 4 or 3 slots]
   //     #if defined(J9VM_THR_LOCK_NURSERY_FAT_ARRAYS)
   //     --clazz-- --flags-- --monitor-- --size-- <--data-->
   //     #else
   //     --clazz-- --flags-- --size-- <--data-->
   //     #endif
   //
   //     for a non-indexable object (if the object has sync methods, monitor
   //     slot is part of the data slots) [header = 2 slots]
   //     --clazz-- --flags-- <--data-->
   //
   // on 64-bit
   //     for an indexable object [header = 3 or 2 slots]
   //     #if defined(J9VM_THR_LOCK_NURSERY_FAT_ARRAYS)
   //     --clazz-- --flags+size-- --monitor-- <--data-->
   //     #else
   //     --clazz-- --flags+size-- <--data-->
   //     #endif
   //
   //     for a non-indexable object [header = 2 slots]
   //     --clazz-- --flags-- <--data-->
   //
   // #else
   //
   // on 32-bit
   //     for an indexable object [header = 4 slots]
   //     --clazz-- --flags-- --monitor-- --size-- <--data-->
   //
   //     for a non-indexable object [header = 3 slots]
   //     --clazz-- --flags-- --monitor-- <--data-->
   //
   // on 64-bit
   //     for an indexable object [header = 3 slots]
   //     --clazz-- --flags+size-- --monitor-- <--data-->
   //
   //     for a non-indexable object [header = 3 slots]
   //     --clazz-- --flags-- --monitor-- <--data-->
   //
   // #endif
   //
   // Packed Objects adds two more fields,
   //

   if (!minRepstosdWords)
      {
      static char *p= feGetEnv("TR_MinRepstosdWords");
      if (p)
         minRepstosdWords = atoi(p);
      else
         minRepstosdWords = MIN_REPSTOSD_WORDS; // Use default value
      }

   int32_t alignmentDelta = 0; // for aligning properly to get best performance from REP TR::InstOpCode::STOSD/TR::InstOpCode::STOSQ

   if (sizeReg || (numSlots + alignmentDelta) >= minRepstosdWords)
      {
      // Zero-initialize by using REP TR::InstOpCode::STOSD/TR::InstOpCode::STOSQ.
      //
      // startOffset will be monitorSlot only for arrays

      generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, segmentReg, generateX86MemoryReference(targetReg, startOfZeroInits, cg), cg);

      if (sizeReg)
         {
         int32_t additionalSlots = 0;

         if (generateArraylets)
            {
            additionalSlots++;
            if (elementSize > sizeof(UDATA))
               additionalSlots++;
            }

         switch (elementSize)
            {
            // Calculate the number of slots by rounding up to number of words,
            // adding in partialHeaderSize.adding in partialHeaderSize.
            //
            case 1:
               if (comp->target().is64Bit())
                  {
                  generateRegMemInstruction(TR::InstOpCode::LEA8RegMem, node, tempReg, generateX86MemoryReference(sizeReg, (additionalSlots*8)+7, cg), cg);
                  generateRegImmInstruction(TR::InstOpCode::SHR8RegImm1, node, tempReg, 3, cg);
                  }
               else
                  {
                  generateRegMemInstruction(TR::InstOpCode::LEA4RegMem, node, tempReg, generateX86MemoryReference(sizeReg, (additionalSlots*4)+3, cg), cg);
                  generateRegImmInstruction(TR::InstOpCode::SHR4RegImm1, node, tempReg, 2, cg);
                  }
               break;
            case 2:
               if (comp->target().is64Bit())
                  {
                  generateRegMemInstruction(TR::InstOpCode::LEA8RegMem, node, tempReg, generateX86MemoryReference(sizeReg, (additionalSlots*4)+3, cg), cg);
                  generateRegImmInstruction(TR::InstOpCode::SHR8RegImm1, node, tempReg, 2, cg);
                  }
               else
                  {
                  generateRegMemInstruction(TR::InstOpCode::LEA4RegMem, node, tempReg, generateX86MemoryReference(sizeReg, (additionalSlots*2)+1, cg), cg);
                  generateRegImmInstruction(TR::InstOpCode::SHR4RegImm1, node, tempReg, 1, cg);
                  }
               break;
            case 4:
               if (comp->target().is64Bit())
                  {
                  generateRegMemInstruction(TR::InstOpCode::LEA8RegMem, node, tempReg, generateX86MemoryReference(sizeReg, (additionalSlots*2)+1, cg), cg);
                  generateRegImmInstruction(TR::InstOpCode::SHR8RegImm1, node, tempReg, 1, cg);
                  }
               else
                  {
                  generateRegMemInstruction(TR::InstOpCode::LEA4RegMem, node, tempReg,
                                            generateX86MemoryReference(sizeReg, additionalSlots, cg), cg);
                  }
               break;
            case 8:
               if (comp->target().is64Bit())
                  {
                  generateRegMemInstruction(TR::InstOpCode::LEA8RegMem, node, tempReg,
                                            generateX86MemoryReference(sizeReg, additionalSlots, cg), cg);
                  }
               else
                  {
                  generateRegMemInstruction(TR::InstOpCode::LEA4RegMem, node, tempReg,
                                            generateX86MemoryReference(NULL, sizeReg,
                                                                    TR::MemoryReference::convertMultiplierToStride(2),
                                                                    additionalSlots, cg), cg);
                  }
               break;
            }
         }
      else
         {
         // Fixed size
         //
         generateRegImmInstruction(TR::InstOpCode::MOVRegImm4(), node, tempReg, numSlots + alignmentDelta, cg);
         if (comp->target().is64Bit())
            {
            // TODO AMD64: replace both instructions with a LEA tempReg, [disp32]
            //
            generateRegRegInstruction(TR::InstOpCode::MOVSXReg8Reg4, node, tempReg, tempReg, cg);
            }
         }

      TR::Register *scratchReg = NULL;
      if (comp->target().is64Bit())
         {
         scratchReg = srm->findOrCreateScratchRegister();
         generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, scratchReg, targetReg, cg);
         }
      else
         {
         generateRegInstruction(TR::InstOpCode::PUSHReg, node, targetReg, cg);
         }

      generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, targetReg, targetReg, cg);

      // We just pushed targetReg on the stack and zeroed it out. targetReg contained the address of the
      // beginning of the header. We want to use the 0-reg to initialize the monitor slot, so we use
      // segmentReg, which points to targetReg+startOfZeroInits and subtract the extra offset.

      bool initLw = (node->getOpCodeValue() != TR::New);
      int lwOffset = fej9->getByteOffsetToLockword(clazz);
      initLw = false;

      if (initLw)
         {
         TR::InstOpCode::Mnemonic op = (comp->target().is64Bit() && fej9->generateCompressedLockWord()) ? TR::InstOpCode::S4MemReg : TR::InstOpCode::SMemReg();
         generateMemRegInstruction(op, node, generateX86MemoryReference(segmentReg, lwOffset-startOfZeroInits, cg), targetReg, cg);
         }

      TR::InstOpCode::Mnemonic op = comp->target().is64Bit() ? TR::InstOpCode::REPSTOSQ : TR::InstOpCode::REPSTOSD;
      generateInstruction(op, node, cg);

      if (comp->target().is64Bit())
         {
         generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, targetReg, scratchReg, cg);
         srm->reclaimScratchRegister(scratchReg);
         }
      else
         {
         generateRegInstruction(TR::InstOpCode::POPReg, node, targetReg, cg);
         }

      return true;
      }

   if (numSlots > 0)
      {
      generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, tempReg, tempReg, cg);

      bool initLw = (node->getOpCodeValue() != TR::New);
      int lwOffset = fej9->getByteOffsetToLockword(clazz);
      initLw = false;

      if (initLw)
         {
         TR::InstOpCode::Mnemonic op = (comp->target().is64Bit() && fej9->generateCompressedLockWord()) ? TR::InstOpCode::S4MemReg : TR::InstOpCode::SMemReg();
         generateMemRegInstruction(op, node, generateX86MemoryReference(targetReg, lwOffset, cg), tempReg, cg);
         }
      }
   else
      {
      bool initLw = (node->getOpCodeValue() != TR::New);
      int lwOffset = fej9->getByteOffsetToLockword(clazz);
      initLw = false;

      if (initLw)
         {
         TR::InstOpCode::Mnemonic op = (comp->target().is64Bit() && fej9->generateCompressedLockWord()) ? TR::InstOpCode::S4MemImm4 : TR::InstOpCode::SMemImm4();
         generateMemImmInstruction(op, node, generateX86MemoryReference(targetReg, lwOffset, cg), 0, cg);
         }
      return false;
      }

   int32_t numIterations = numSlots/maxZeroInitWordsPerIteration;
   if (numIterations > 1)
      {
      // Generate the initializations in a loop
      //
      int32_t numLoopSlots = numIterations*maxZeroInitWordsPerIteration;
      int32_t endOffset;

      endOffset = (int32_t)(numLoopSlots*TR::Compiler->om.sizeofReferenceAddress() + startOfZeroInits);

      generateRegImmInstruction(TR::InstOpCode::MOVRegImm4(), node, segmentReg, -((numIterations-1)*maxZeroInitWordsPerIteration), cg);

      if (comp->target().is64Bit())
         generateRegRegInstruction(TR::InstOpCode::MOVSXReg8Reg4, node, segmentReg, segmentReg, cg);

      TR::LabelSymbol *loopLabel = generateLabelSymbol(cg);
      generateLabelInstruction(TR::InstOpCode::label, node, loopLabel, cg);
      for (i = maxZeroInitWordsPerIteration; i > 0; i--)
         {
         generateMemRegInstruction(TR::InstOpCode::SMemReg(), node,
                                   generateX86MemoryReference(targetReg,
                                                           segmentReg,
                                                           TR::MemoryReference::convertMultiplierToStride((int32_t)TR::Compiler->om.sizeofReferenceAddress()),
                                                           endOffset - TR::Compiler->om.sizeofReferenceAddress()*i, cg),
                                   tempReg, cg);
         }
      generateRegImmInstruction(TR::InstOpCode::ADDRegImms(), node, segmentReg, maxZeroInitWordsPerIteration, cg);
      generateLabelInstruction(TR::InstOpCode::JLE4, node, loopLabel, cg);

      // Generate the left-over initializations
      //
      for (i = 0; i < numSlots % maxZeroInitWordsPerIteration; i++)
         {
         generateMemRegInstruction(TR::InstOpCode::SMemReg(), node,
                                   generateX86MemoryReference(targetReg,
                                                           endOffset+TR::Compiler->om.sizeofReferenceAddress()*i, cg),
                                   tempReg, cg);
         }
      }
   else
      {
      // Generate the initializations inline
      //
      for (i = 0; i < numSlots; i++)
         {
         // Don't bother initializing the array-size slot
         //
         generateMemRegInstruction(TR::InstOpCode::SMemReg(), node,
                                   generateX86MemoryReference(targetReg,
                                   i*TR::Compiler->om.sizeofReferenceAddress() + startOfZeroInits, cg),
                                   tempReg, cg);
         }
      }

   return false;
   }

TR::Register *
objectCloneEvaluator(
      TR::Node *node,
      TR::CodeGenerator *cg)
   {
   /*
    * Commented out Object.clone() code has been removed for code cleanliness.
    * If it needs to be resurrected it can be found in RTC or CMVC.
    */
   return NULL;
   }

#ifdef J9VM_GC_SPARSE_HEAP_ALLOCATION
static void handleOffHeapDataForArrays(
      TR::Node *node,
      TR::Register *sizeReg,
      TR::Register *targetReg,
      TR::Register *tempReg,
      TR_X86ScratchRegisterManager *srm,
      TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());

   /* Here we'll update dataAddr slot for both fixed and variable length arrays. Fixed length arrays are
    * simple as we just need to check first child of the node for array size. For variable length arrays,
    * runtime size checks are needed to determine whether to use contiguous or discontiguous header layout.
    *
    * In both scenarios, arrays of non-zero size use contiguous header layout while zero size arrays use
    * discontiguous header layout. DataAddr field of zero size arrays is intialized to NULL because they
    * don't have any data elements.
    */
   TR::MemoryReference *dataAddrSlotMR = NULL;
   TR::MemoryReference *dataAddrMR = NULL;
   TR::Register *zeroReg = NULL;
   if (TR::Compiler->om.compressObjectReferences() && NULL != sizeReg)
      {
      /* We need to check sizeReg at runtime to determine correct offset of dataAddr field.
       * Here we deal only with compressed refs because dataAddr field offset for discontiguous
       * and contiguous arrays is the same in full refs.
       */
      if (comp->getOption(TR_TraceCG))
         traceMsg(comp, "Node (%p): Dealing with compressed refs variable length array.\n", node);

      TR_ASSERT_FATAL_WITH_NODE(node,
         (fej9->getOffsetOfDiscontiguousDataAddrField() - fej9->getOffsetOfContiguousDataAddrField()) == 8,
         "Offset of dataAddr field in discontiguous array is expected to be 8 bytes more than contiguous array. "
         "But was %d bytes for discontiguous and %d bytes for contiguous array.\n",
         fej9->getOffsetOfDiscontiguousDataAddrField(), fej9->getOffsetOfContiguousDataAddrField());

      TR::Register *discontiguousDataAddrOffsetReg = srm->findOrCreateScratchRegister();
      generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, discontiguousDataAddrOffsetReg, discontiguousDataAddrOffsetReg, cg);
      // Since array size is capped at 32 bits, we only need to check lower half (0-31 bits) of sizeReg.
      generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, sizeReg, 1, cg);
      generateRegImmInstruction(TR::InstOpCode::ADCRegImm4(), node, discontiguousDataAddrOffsetReg, 0, cg);

      dataAddrMR = generateX86MemoryReference(targetReg, discontiguousDataAddrOffsetReg, 3, TR::Compiler->om.contiguousArrayHeaderSizeInBytes(), cg);
      dataAddrSlotMR = generateX86MemoryReference(targetReg, discontiguousDataAddrOffsetReg, 3, fej9->getOffsetOfContiguousDataAddrField(), cg);
      // Load first data element address
      generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, tempReg, dataAddrMR, cg);

      // Clear out tempReg if dealing with 0 length array
      zeroReg = srm->findOrCreateScratchRegister();
      generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, zeroReg, zeroReg, cg);
      // Since array size is capped at 32 bits, we only need to check lower half (0-31 bits) of sizeReg.
      generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, sizeReg, sizeReg, cg);
      generateRegRegInstruction(TR::InstOpCode::CMOVERegReg(), node, tempReg, zeroReg, cg);
      srm->reclaimScratchRegister(zeroReg);

      // Write first data element address to dataAddr slot
      generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, dataAddrSlotMR, tempReg, cg);
      srm->reclaimScratchRegister(discontiguousDataAddrOffsetReg);
      }
   else if (NULL == sizeReg && node->getFirstChild()->getOpCode().isLoadConst() && node->getFirstChild()->getInt() == 0)
      {
      if (comp->getOption(TR_TraceCG))
         traceMsg(comp, "Node (%p): Dealing with full/compressed refs fixed length zero size array.\n", node);

      dataAddrSlotMR = generateX86MemoryReference(targetReg, fej9->getOffsetOfDiscontiguousDataAddrField(), cg);
      generateMemImmInstruction(TR::InstOpCode::SMemImm4(), node, dataAddrSlotMR, 0, cg);
      }
   else
      {
      if (comp->getOption(TR_TraceCG))
         {
         traceMsg(comp,
            "Node (%p): Dealing with either full/compressed refs fixed length non-zero size array or full refs variable length array.\n",
            node);
         }

      if (!TR::Compiler->om.compressObjectReferences())
         {
         TR_ASSERT_FATAL_WITH_NODE(node,
            fej9->getOffsetOfDiscontiguousDataAddrField() == fej9->getOffsetOfContiguousDataAddrField(),
            "dataAddr field offset is expected to be same for both contiguous and discontiguous arrays in full refs. "
            "But was %d bytes for discontiguous and %d bytes for contiguous array.\n",
            fej9->getOffsetOfDiscontiguousDataAddrField(), fej9->getOffsetOfContiguousDataAddrField());
         }

      dataAddrMR = generateX86MemoryReference(targetReg, TR::Compiler->om.contiguousArrayHeaderSizeInBytes(), cg);
      dataAddrSlotMR = generateX86MemoryReference(targetReg, fej9->getOffsetOfContiguousDataAddrField(), cg);
      // Load first data element address
      generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, tempReg, dataAddrMR, cg);

      if (!TR::Compiler->om.compressObjectReferences() && NULL != sizeReg)
         {
         // Clear out tempReg if dealing with 0 length array
         zeroReg = srm->findOrCreateScratchRegister();
         generateRegRegInstruction(TR::InstOpCode::XORRegReg(), node, zeroReg, zeroReg, cg);
         // Since array size is capped at 32 bits, we only need to check lower half (0-31 bits) of sizeReg.
         generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, sizeReg, sizeReg, cg);
         generateRegRegInstruction(TR::InstOpCode::CMOVERegReg(), node, tempReg, zeroReg, cg);
         srm->reclaimScratchRegister(zeroReg);
         }
      // Write first data element address to dataAddr slot
      generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, dataAddrSlotMR, tempReg, cg);
      }
   }
#endif /* J9VM_GC_SPARSE_HEAP_ALLOCATION */

static void verifyInlinedAllocation(
      TR::Node *node,
      TR_OpaqueClassBlock *clazz,
      int32_t allocationSize,
      TR::LabelSymbol *failLabel,
      TR::Instruction *startInstr,
      TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();

   startInstr = startInstr->getNext();
   TR_OpaqueClassBlock *classToValidate = clazz;

   TR_RelocationRecordInformation *recordInfo =
      (TR_RelocationRecordInformation *) comp->trMemory()->allocateMemory(sizeof(TR_RelocationRecordInformation), heapAlloc);
   recordInfo->data1 = allocationSize;
   recordInfo->data2 = node->getInlinedSiteIndex();
   recordInfo->data3 = (uintptr_t) failLabel;
   recordInfo->data4 = (uintptr_t) startInstr;

   TR::SymbolReference *classSymRef;
   TR_ExternalRelocationTargetKind reloKind;

   if (node->getOpCodeValue() == TR::New)
      {
      classSymRef = node->getFirstChild()->getSymbolReference();
      reloKind = TR_VerifyClassObjectForAlloc;
      }
   else
      {
      classSymRef = node->getSecondChild()->getSymbolReference();
      reloKind = TR_VerifyRefArrayForAlloc;

      if (comp->getOption(TR_UseSymbolValidationManager))
         {
         classToValidate = comp->fej9()->getComponentClassFromArrayClass(classToValidate);
         }
      }

   if (comp->getOption(TR_UseSymbolValidationManager))
      {
      TR_ASSERT(classToValidate, "classToValidate should not be NULL, clazz=%p\n", clazz);
      recordInfo->data5 = (uintptr_t)classToValidate;
      }

   cg->addExternalRelocation(new (cg->trHeapMemory())
      TR::BeforeBinaryEncodingExternalRelocation(
         startInstr,
         (uint8_t *) classSymRef,
         (uint8_t *) recordInfo,
         reloKind, cg),
      __FILE__, __LINE__, node);
   }

TR::Register *
J9::X86::TreeEvaluator::VMnewEvaluator(
      TR::Node *node,
      TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = comp->fej9();

   if (comp->suppressAllocationInlining())
      return NULL;

   if (comp->getOption(TR_DisableAllocationInlining))
      return NULL;

   // If the helper does not preserve all the registers there will not be
   // enough registers to do the inline allocation.
   // Also, don't do the inline allocation if optimizing for space
   //
   TR::MethodSymbol *helperSym = node->getSymbol()->castToMethodSymbol();
   if (!helperSym->preservesAllRegisters())
      return NULL;

   bool realTimeGC = comp->getOptions()->realTimeGC();
   bool generateArraylets = comp->generateArraylets();

   TR_OpaqueClassBlock *clazz = NULL;
   bool isArrayNew = false;
   int32_t allocationSize = 0;
   int32_t objectSize = 0;
   int32_t elementSize = 0;
   int32_t dataOffset = 0;

   TR_X86ScratchRegisterManager *srm = cg->generateScratchRegisterManager(comp->target().is64Bit() ? 8 : 7);

   TR::Register *classReg   = NULL;
   TR::Register *segmentReg = NULL;
   TR::Register *tempReg    = NULL;
   TR::Register *targetReg  = NULL;
   TR::Register *sizeReg    = NULL;

   /**
    * Study of registers used in inline allocation.
    *
    * Result goes to targetReg. Unless outlinedHelperCall is used, which requires an extra register move to targetReg2.
    *    targetReg2 is needed because the result needs to be CollectedReferenceRegister, but only after object is ready.
    *
    * classReg contains the J9Class for the object to be allocated. Not always used; instead, when loadaddr is not evaluated, it
    *    is rematerialized like a constant (in which case, clazz contains the known value). When it is rematerialized, there are
    *    'interesting' AOT/HCR patching routines.
    *
    * sizeReg is used for array allocations to hold the number of elements. However...
    *    for packed variable (objectSize==0) arrays, sizeReg behaves like segmentReg should (i.e. contains size in _bytes_): elementSize
    *    is set to 1 and sizeReg is result of multiplication of real elementSize vs element count.
    *
    * segmentReg contains the size, _in bytes!_, of the object/array to be allocated. When outlining is used, it will be bound to edi.
    *    This must contain the rounding (i.e. 8-aligned, so address will always end in 0x0 or 0x8). When size cannot be known (i.e.
    *    dynamic array size) explicit assembly is generated to do rounding (allocationSize is reused to contain the header offset).
    *    After tlh-top comparison, this register is reused as a temporary register (i.e. genHeapAlloc in non-outlined path, and
    *    inside the outlined codert asm sequences). This size is not available at non-outlined zero-initialization routine and needs
    *    to be re-materialized.
    *
    */

   // --------------------------------------------------------------------------------
   //
   // Find the class info and allocation size depending on the node type.
   //
   // Returns:
   //    size of object    includes the size of the array header
   //    -1                cannot allocate inline
   //    0                 variable sized allocation
   //
   // --------------------------------------------------------------------------------

   objectSize = comp->canAllocateInline(node, clazz);
   if (objectSize < 0)
      return NULL;

   // Currently dynamic allocation is only supported on reference array.
   // We are performing dynamic array allocation if both object size and
   // class block cannot be statically determined.
   //
   bool dynamicArrayAllocation =
      (node->getOpCodeValue() == TR::anewarray) &&
      (objectSize == 0) &&
      (clazz == NULL);

   allocationSize = objectSize;

   static long count = 0;
   if (!performTransformation(comp, "O^O <%3d> Inlining Allocation of %s [0x%p].\n", count++, node->getOpCode().getName(), node))
      return NULL;

   if (node->getOpCodeValue() == TR::New)
      {
      // realtimeGC: cannot inline if object size is too big to get a size class
      if (realTimeGC)
         {
         if ((uint32_t) objectSize > fej9->getMaxObjectSizeForSizeClass())
            return NULL;
         }

      dataOffset = TR::Compiler->om.objectHeaderSizeInBytes(); //Not used...
      classReg = node->getFirstChild()->getRegister();

      // For Non-SVM AOT, the class has to be in a register
      if (TR::Compiler->om.areValueTypesEnabled() &&
          !classReg &&
          cg->needClassAndMethodPointerRelocations() &&
          !comp->getOption(TR_UseSymbolValidationManager))
         {
         classReg = cg->evaluate(node->getFirstChild());

         if (comp->getOption(TR_TraceCG))
            {
            traceMsg(comp, "%s: evaluate loadaddr: clazz %p classReg %s\n", __FUNCTION__, clazz, classReg ? classReg->getRegisterName(comp) : "<none>");
            }
         }

      TR_ASSERT_FATAL_WITH_NODE(node, objectSize > 0, "Object size must be known");
      }
   else
      {
      if (node->getOpCodeValue() == TR::newarray)
         {
         elementSize = TR::Compiler->om.getSizeOfArrayElement(node);
         }
      else
         {
         // Must be TR::anewarray
         //
         elementSize = comp->useCompressedPointers() ?
            TR::Compiler->om.sizeofReferenceField() :
            (int32_t)TR::Compiler->om.sizeofReferenceAddress();

         classReg = node->getSecondChild()->getRegister();

         // For dynamic array allocation, need to evaluate second child
         if (!classReg && dynamicArrayAllocation)
            classReg = cg->evaluate(node->getSecondChild());
         }

      isArrayNew = true;

      dataOffset = generateArraylets ?
         fej9->getArrayletFirstElementOffset(elementSize, comp) :
         TR::Compiler->om.contiguousArrayHeaderSizeInBytes();
      }

   bool enableTLHBatchClearing = fej9->tlhHasBeenCleared();

#ifdef J9VM_GC_NON_ZERO_TLH
   if (node->canSkipZeroInitialization() &&
       (enableTLHBatchClearing || !comp->getOption(TR_DisableDualTLH)) &&
       !realTimeGC)
      {
      // Choose appropriate helper call if zero initialization can be skipped
      //
      TR::SymbolReference *noZeroInitSymRef = NULL;
      TR::SymbolReferenceTable *symRefTab = comp->getSymRefTab();

      switch (node->getOpCodeValue())
         {
         case TR::New:
            // For value types, it should use the jitNewValue helper call which
            // is set up before codegen
            //
            if (!TR::Compiler->om.areValueTypesEnabled() ||
               (node->getSymbolReference() != symRefTab->findOrCreateNewValueSymbolRef(comp->getMethodSymbol())))
               {
               noZeroInitSymRef = symRefTab->findOrCreateNewObjectNoZeroInitSymbolRef(comp->getMethodSymbol());
               }
            break;

         case TR::newarray:
            noZeroInitSymRef = symRefTab->findOrCreateNewArrayNoZeroInitSymbolRef(comp->getMethodSymbol());
            break;

         case TR::anewarray:
            noZeroInitSymRef = symRefTab->findOrCreateANewArrayNoZeroInitSymbolRef(comp->getMethodSymbol());
            break;

         default:
            break;
         }

      if (noZeroInitSymRef)
         {
         node->setSymbolReference(noZeroInitSymRef);
         }

      if (comp->getOption(TR_TraceCG))
         traceMsg(comp, "SKIPZEROINIT: for %p, change the symbol to %p ", node, node->getSymbolReference());
      }
   else
      {
      if (comp->getOption(TR_TraceCG))
         traceMsg(comp, "NOSKIPZEROINIT: for %p,  keep symbol as %p ", node, node->getSymbolReference());
      }
#endif

   segmentReg = srm->findOrCreateScratchRegister();
   tempReg = srm->findOrCreateScratchRegister();

   // If the size is variable, evaluate it into a register
   //
   if (objectSize == 0)
      {
      sizeReg = cg->evaluate(node->getFirstChild());
      allocationSize += dataOffset;
      if (comp->getOption(TR_TraceCG))
         traceMsg(comp, "allocationSize %d dataOffset %d\n", allocationSize, dataOffset);
      }
   else
      {
      sizeReg = NULL;
      }

   TR::LabelSymbol *startLabel = generateLabelSymbol(cg);
   startLabel->setStartInternalControlFlow();
   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

   // Generate the helper call for out-of-line allocation
   //
   targetReg = srm->findOrCreateScratchRegister();
   TR::LabelSymbol *fallThru = generateLabelSymbol(cg);
   fallThru->setEndInternalControlFlow();
   TR::LabelSymbol *failLabel = generateLabelSymbol(cg);

   TR_OutlinedInstructions *outlinedHelperCall =
      new (cg->trHeapMemory()) TR_OutlinedInstructions(node, TR::acall, targetReg, failLabel, fallThru, cg);
   cg->getOutlinedInstructionsList().push_front(outlinedHelperCall);

   TR::Instruction *startInstr = cg->getAppendInstruction();

   // --------------------------------------------------------------------------------
   // Do the allocation from the TLH and bump pointers.
   //
   // The address of the start of the allocated heap space will be in targetReg.
   // --------------------------------------------------------------------------------

   bool doInlineAllocationForObjectOrHybridArraylet = (!realTimeGC && !generateArraylets) ? true : false;

   if (doInlineAllocationForObjectOrHybridArraylet)
      {
      genHeapAllocForObjectOrHybridArraylet(node, clazz, allocationSize, elementSize, sizeReg, targetReg, segmentReg, tempReg, failLabel, cg);
      }
   else
      {
      genHeapAllocForDiscontiguousArraysOrRealtime(node, clazz, allocationSize, elementSize, sizeReg, targetReg, segmentReg, tempReg, failLabel, cg);
      }

   // --------------------------------------------------------------------------------
   // Perform zero-initialization on data slots.
   //
   // There may be information about which slots are to be zero-initialized.
   // If there is no information, all slots must be zero-initialized.
   // --------------------------------------------------------------------------------

   bool useRepInstruction;
   bool monitorSlotIsInitialized;

   TR::Register *scratchReg = NULL;
   bool shouldInitZeroSizedArrayHeader = true;

#ifdef J9VM_GC_NON_ZERO_TLH
   if (!enableTLHBatchClearing || realTimeGC)
      {
#endif
      if (!maxZeroInitWordsPerIteration)
         {
         static char *p = feGetEnv("TR_MaxZeroInitWordsPerIteration");
         maxZeroInitWordsPerIteration = p ? atoi(p) : MAX_ZERO_INIT_WORDS_PER_ITERATION;
         }

      TR_ExtraInfoForNew *initInfo = node->getSymbolReference()->getExtraInfo();

      if (initInfo && initInfo->zeroInitSlots)
         {
         // If there are too many words to be individually initialized, initialize
         // them all
         //
         if (initInfo->numZeroInitSlots >= maxZeroInitWordsPerIteration*2-1)
            initInfo->zeroInitSlots = NULL;
         }

      if (initInfo && initInfo->zeroInitSlots)
         {
         // Zero-initialize by explicit zero stores.
         // Use the supplied bit vector to identify which slots to initialize
         //
         // Zero-initialize the monitor slot in the header at the same time.
         //
         TR_BitVectorIterator bvi(*initInfo->zeroInitSlots);
         static bool UseOldBVI = feGetEnv("TR_UseOldBVI");
         if (UseOldBVI)
            {
            generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, tempReg, tempReg, cg);
            while (bvi.hasMoreElements())
               {
               generateMemRegInstruction(TR::InstOpCode::S4MemReg, node,
                                         generateX86MemoryReference(targetReg, bvi.getNextElement()*4 +dataOffset, cg),
                                         tempReg, cg);
               }
            }
         else
            {
            int32_t lastElementIndex = -1;
            int32_t nextE = -2;
            int32_t span = 0;
            int32_t lastSpan = -1;
            scratchReg = srm->findOrCreateScratchRegister(TR_FPR);
            generateRegRegInstruction(TR::InstOpCode::PXORRegReg, node, scratchReg, scratchReg, cg);
            while (bvi.hasMoreElements())
               {
               nextE = bvi.getNextElement();
               if (-1 == lastElementIndex) lastElementIndex = nextE;
               span = nextE - lastElementIndex;
               TR_ASSERT(span>=0, "SPAN < 0");
               if (span < 3)
                  {
                  lastSpan = span;
                  continue;
                  }
               else if (span == 3)
                  {
                  generateMemRegInstruction(TR::InstOpCode::MOVDQUMemReg, node, generateX86MemoryReference(targetReg, lastElementIndex*4 +dataOffset, cg), scratchReg, cg);
                  lastSpan = -1;
                  lastElementIndex = -1;
                  }
               else if (span > 3)
                  {
                  TR::InstOpCode::Mnemonic storeOpCode;
                  if (lastSpan == 0)
                     {
                     storeOpCode = TR::InstOpCode::MOVDMemReg;
                     }
                  else if (lastSpan == 1)
                     {
                     storeOpCode = TR::InstOpCode::MOVQMemReg;
                     }
                  else
                     {
                     storeOpCode = TR::InstOpCode::MOVDQUMemReg;
                     }

                  generateMemRegInstruction(storeOpCode, node, generateX86MemoryReference(targetReg, lastElementIndex*4 +dataOffset, cg), scratchReg, cg);

                  lastElementIndex = nextE;
                  lastSpan = 0;
                  }
               }

            int32_t adjustedDataOffset = dataOffset;
            TR::InstOpCode::Mnemonic storeOpCode = TR::InstOpCode::bad;

            switch (lastSpan)
               {
               case 0:
                  storeOpCode = TR::InstOpCode::MOVDMemReg;
                  break;
               case 1:
                  storeOpCode = TR::InstOpCode::MOVQMemReg;
                  break;
               case 2:
                  TR_ASSERT(dataOffset >= 4, "dataOffset must be >= 4.");
                  storeOpCode = TR::InstOpCode::MOVDQUMemReg;
                  adjustedDataOffset -= 4;
                  break;
               default:
                  break;
               }

            if (storeOpCode != TR::InstOpCode::bad)
               {
               generateMemRegInstruction(storeOpCode, node, generateX86MemoryReference(targetReg, lastElementIndex*4 + adjustedDataOffset, cg), scratchReg, cg);
               }

            srm->reclaimScratchRegister(scratchReg);
            }

         useRepInstruction = false;

         J9JavaVM * jvm = fej9->getJ9JITConfig()->javaVM;
         monitorSlotIsInitialized = (jvm->lockwordMode != LOCKNURSERY_ALGORITHM_ALL_INHERIT);
         }
      else if ((!initInfo || initInfo->numZeroInitSlots > 0) &&
               !node->canSkipZeroInitialization())
         {
         // Initialize all slots
         //
         if (doInlineAllocationForObjectOrHybridArraylet)
            {
            useRepInstruction = genZeroInitForEntireObjectOrHybridArraylet(node, objectSize, elementSize, sizeReg, targetReg, tempReg, segmentReg, srm, cg);
            shouldInitZeroSizedArrayHeader = false;
            }
         else
            {
            useRepInstruction = genZeroInitEntireObject(node, objectSize, elementSize, sizeReg, targetReg, tempReg, segmentReg, srm, cg);
            }

         J9JavaVM * jvm = fej9->getJ9JITConfig()->javaVM;
         monitorSlotIsInitialized = (jvm->lockwordMode != LOCKNURSERY_ALGORITHM_ALL_INHERIT);
         }
      else
         {
         // Skip data initialization
         //
         if (doInlineAllocationForObjectOrHybridArraylet)
            {
            // Even though we can skip the data initialization, for arrays of unknown size we still have
            // to initialize at least one slot to cover the discontiguous length field in case the array
            // is zero sized.  This is because the length is not checked at runtime and is only needed
            // for non-native 64-bit targets where the discontiguous length slot is already initialized
            // via the contiguous length slot.
            //
            if (node->getOpCodeValue() != TR::New &&
                (comp->target().is32Bit() || comp->useCompressedPointers()))
               {
               generateMemImmInstruction(TR::InstOpCode::SMemImm4(), node,
                  generateX86MemoryReference(targetReg, fej9->getOffsetOfDiscontiguousArraySizeField(), cg),
                  0, cg);
               shouldInitZeroSizedArrayHeader = false;
               }
            }

         monitorSlotIsInitialized = false;
         useRepInstruction = false;
         }
#ifdef J9VM_GC_NON_ZERO_TLH
      }
   else
      {
      monitorSlotIsInitialized = false;
      useRepInstruction = false;
      }
#endif

   // --------------------------------------------------------------------------------
   // Initialize the header
   // --------------------------------------------------------------------------------

   if (isArrayNew)
      {
      TR::Register *classArgReg;
      bool isDynamicAllocationArg;

      if ((fej9->inlinedAllocationsMustBeVerified() && !comp->getOption(TR_UseSymbolValidationManager) && node->getOpCodeValue() == TR::anewarray) ||
          dynamicArrayAllocation)
         {
         // If dynamic array allocation, must pass in classReg to initialize the array header
         //
         classArgReg = classReg;
         isDynamicAllocationArg = true;
         }
      else
         {
         classArgReg = NULL;
         isDynamicAllocationArg = false;
         }

      genInitArrayHeader(
         node,
         clazz,
         classArgReg,
         targetReg,
         sizeReg,
         elementSize,
         dataOffset,
         tempReg,
         monitorSlotIsInitialized,
         isDynamicAllocationArg,
         shouldInitZeroSizedArrayHeader,
         cg);
      }
   else
      {
      genInitObjectHeader(node, clazz, classReg, targetReg, tempReg, monitorSlotIsInitialized, false, cg);
      }

#ifdef J9VM_GC_SPARSE_HEAP_ALLOCATION
   if (isArrayNew && TR::Compiler->om.isOffHeapAllocationEnabled())
      {
      handleOffHeapDataForArrays(node, sizeReg, targetReg, tempReg, srm, cg);
      }
#endif /* J9VM_GC_SPARSE_HEAP_ALLOCATION */

   if (fej9->inlinedAllocationsMustBeVerified() &&
       (node->getOpCodeValue() == TR::New || node->getOpCodeValue() == TR::anewarray))
      {
      verifyInlinedAllocation(node, clazz, allocationSize, failLabel, startInstr, cg);
      }

   // 1 == vmThread
   int32_t numDeps = 2;

   if (useRepInstruction)
      numDeps += 2;

   if (sizeReg)
      numDeps++;
   if (classReg)
      numDeps++;

   // Outlined helper call
   //
   if (node->getOpCodeValue() == TR::New)
      numDeps++;
   else
      numDeps += 2;

   numDeps += srm->numAvailableRegisters();

   TR::RegisterDependencyConditions *deps =
      generateRegisterDependencyConditions((uint8_t)0, numDeps, cg);

   if (sizeReg)
      deps->addPostCondition(sizeReg, TR::RealRegister::NoReg, cg);
   if (classReg)
      deps->addPostCondition(classReg, TR::RealRegister::NoReg, cg);

   deps->addPostCondition(targetReg, TR::RealRegister::eax, cg);
   deps->addPostCondition(cg->getVMThreadRegister(), TR::RealRegister::ebp, cg);

   if (useRepInstruction)
      {
      // These real register dependencies must be added here because the same
      // virtuals may appear in the scratch register manager
      //
      deps->addPostCondition(tempReg, TR::RealRegister::ecx, cg);
      deps->addPostCondition(segmentReg, TR::RealRegister::edi, cg);
      }

   // Outlined helper call
   //
   TR::Node *callNode = outlinedHelperCall->getCallNode();
   TR::Register *reg;

   if (callNode->getFirstChild() == node->getFirstChild())
      {
      reg = callNode->getFirstChild()->getRegister();
      if (reg)
         deps->unionPostCondition(reg, TR::RealRegister::NoReg, cg);
      }

   if (node->getOpCodeValue() != TR::New)
      {
      if (callNode->getSecondChild() == node->getSecondChild())
         {
         reg = callNode->getSecondChild()->getRegister();
         if (reg)
            deps->unionPostCondition(reg, TR::RealRegister::NoReg, cg);
         }
      }

   srm->addScratchRegistersToDependencyList(deps);

   deps->stopAddingConditions();

   generateLabelInstruction(TR::InstOpCode::label, node, fallThru, deps, cg);

   // Copy the newly allocated object into a collected reference register
   // now that it is a valid object.
   //
   TR::Register *targetReg2 = cg->allocateCollectedReferenceRegister();
   TR::RegisterDependencyConditions  *deps2 = generateRegisterDependencyConditions(0, 1, cg);
   deps2->addPostCondition(targetReg2, TR::RealRegister::eax, cg);
   generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, targetReg2, targetReg, deps2, cg);
   cg->stopUsingRegister(targetReg);
   targetReg = targetReg2;

   srm->stopUsingRegisters();

   cg->decReferenceCount(node->getFirstChild());
   if (isArrayNew)
      cg->decReferenceCount(node->getSecondChild());

   node->setRegister(targetReg);
   return targetReg;
   }


// Generate instructions to type-check a store into a reference-type array.
// The code sequence determines if the destination is an array of "java/lang/Object" instances,
// or if the source object has the correct type (i.e. equal to the component type of the array).
//
void
J9::X86::TreeEvaluator::VMarrayStoreCHKEvaluator(
      TR::Node *node,
      TR::Node *sourceChild,
      TR::Node *destinationChild,
      TR_X86ScratchRegisterManager *scratchRegisterManager,
      TR::LabelSymbol *wrtbarLabel,
      TR::Instruction *prevInstr,
      TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(comp->fe());
   TR::Register *sourceReg  = sourceChild->getRegister();
   TR::Register *destReg = destinationChild->getRegister();
   TR::LabelSymbol *helperCallLabel = generateLabelSymbol(cg);

   static char *disableArrayStoreCheckOpts = feGetEnv("TR_disableArrayStoreCheckOpts");
   if (!disableArrayStoreCheckOpts || !debug("noInlinedArrayStoreCHKs"))
      {
      // If the component type of the array is equal to the type of the source reference,
      // then the store always succeeds. The component type of the array is stored in a
      // field of the J9ArrayClass that represents the type of the array.
      //

      TR::Register *sourceClassReg = scratchRegisterManager->findOrCreateScratchRegister();
      TR::Register *destComponentClassReg = scratchRegisterManager->findOrCreateScratchRegister();

      TR::Instruction* instr;

      if (TR::Compiler->om.compressObjectReferences())
         {

         // FIXME: Add check for hint when doing the arraystore check as below when class pointer compression
         // is enabled.

         TR::MemoryReference *destTypeMR = generateX86MemoryReference(destReg, TR::Compiler->om.offsetOfObjectVftField(), cg);

         generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, destComponentClassReg, destTypeMR, cg); // class pointer is 32 bits
         TR::TreeEvaluator::generateVFTMaskInstruction(node, destComponentClassReg, cg);

         // -------------------------------------------------------------------------
         //
         // If the component type is java.lang.Object then the store always succeeds.
         //
         // -------------------------------------------------------------------------

         TR_OpaqueClassBlock *objectClass = fej9->getSystemClassFromClassName("java/lang/Object", 16);

         TR_ASSERT((((uintptr_t)objectClass) >> 32) == 0, "TR_OpaqueClassBlock must fit on 32 bits when using class pointer compression");
         instr = generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, destComponentClassReg, (uint32_t) ((uint64_t) objectClass), cg);

         generateLabelInstruction(TR::InstOpCode::JE4, node, wrtbarLabel, cg);

         // here we may have to convert the TR_OpaqueClassBlock into a J9Class pointer
         // and store it in destComponentClassReg
         // ..

         TR::MemoryReference *destCompTypeMR =
            generateX86MemoryReference(destComponentClassReg, offsetof(J9ArrayClass, componentType), cg);
         generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, destComponentClassReg, destCompTypeMR, cg);

         // here we may have to convert the J9Class pointer from destComponentClassReg into
         // a TR_OpaqueClassBlock and store it back into destComponentClassReg
         // ..

         TR::MemoryReference *sourceRegClassMR = generateX86MemoryReference(sourceReg, TR::Compiler->om.offsetOfObjectVftField(), cg);
         generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, sourceClassReg, sourceRegClassMR, cg);
         TR::TreeEvaluator::generateVFTMaskInstruction(node, sourceClassReg, cg);

         generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, destComponentClassReg, sourceClassReg, cg); // compare only 32 bits
         generateLabelInstruction(TR::InstOpCode::JE4, node, wrtbarLabel, cg);

         // -------------------------------------------------------------------------
         //          // Check the source class cast cache
         //
         // -------------------------------------------------------------------------

         generateMemRegInstruction(
            TR::InstOpCode::CMP4MemReg,
            node,
            generateX86MemoryReference(sourceClassReg, offsetof(J9Class, castClassCache), cg), destComponentClassReg, cg);
         }
      else // no class pointer compression
         {
         TR::MemoryReference *sourceClassMR = generateX86MemoryReference(sourceReg, TR::Compiler->om.offsetOfObjectVftField(), cg);
         generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, sourceClassReg, sourceClassMR, cg);
         TR::TreeEvaluator::generateVFTMaskInstruction(node, sourceClassReg, cg);

         TR::MemoryReference *destClassMR = generateX86MemoryReference(destReg, TR::Compiler->om.offsetOfObjectVftField(), cg);
         generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, destComponentClassReg, destClassMR, cg);
         TR::TreeEvaluator::generateVFTMaskInstruction(node, destComponentClassReg, cg);
         TR::MemoryReference *destCompTypeMR =
            generateX86MemoryReference(destComponentClassReg, offsetof(J9ArrayClass, componentType), cg);
         generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, destComponentClassReg, destCompTypeMR, cg);

         generateRegRegInstruction(TR::InstOpCode::CMPRegReg(), node, destComponentClassReg, sourceClassReg, cg);
         generateLabelInstruction(TR::InstOpCode::JE4, node, wrtbarLabel, cg);

         // -------------------------------------------------------------------------
         //
         // Check the source class cast cache
         //
         // -------------------------------------------------------------------------

         generateMemRegInstruction(
            TR::InstOpCode::CMPMemReg(),
            node,
            generateX86MemoryReference(sourceClassReg, offsetof(J9Class, castClassCache), cg), destComponentClassReg, cg);
         }
      generateLabelInstruction(TR::InstOpCode::JE4, node, wrtbarLabel, cg);

      instr = NULL;
      /*
      TR::Instruction *instr;


      // -------------------------------------------------------------------------
      //
      // If the component type is java.lang.Object then the store always succeeds.
      //
      // -------------------------------------------------------------------------

      TR_OpaqueClassBlock *objectClass = fej9->getSystemClassFromClassName("java/lang/Object", 16);

      if (comp->target().is64Bit())
         {
            if (TR::Compiler->om.compressObjectReferences())
               {
               TR_ASSERT((((uintptr_t)objectClass) >> 32) == 0, "TR_OpaqueClassBlock must fit on 32 bits when using class pointer compression");
               instr = generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, destComponentClassReg, (uint32_t) ((uint64_t) objectClass), cg);
               }
            else // 64 bit but no class pointer compression
               {
               if ((uintptr_t)objectClass <= (uintptr_t)0x7fffffff)
                  {
                  instr = generateRegImmInstruction(TR::InstOpCode::CMP8RegImm4, node, destComponentClassReg, (uintptr_t) objectClass, cg);
                  }
               else
                  {
                  TR::Register *objectClassReg = scratchRegisterManager->findOrCreateScratchRegister();
                  instr = generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, objectClassReg, (uintptr_t) objectClass, cg);
                  generateRegRegInstruction(TR::InstOpCode::CMP8RegReg, node, destComponentClassReg, objectClassReg, cg);
                  scratchRegisterManager->reclaimScratchRegister(objectClassReg);
                  }
               }
         }
      else
         {
         instr = generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, destComponentClassReg, (int32_t)(uintptr_t) objectClass, cg);
         }

      generateLabelInstruction(TR::InstOpCode::JE4, node, wrtbarLabel, cg);
      */


      // ---------------------------------------------
      //
      // If isInstanceOf (objectClass,ArrayComponentClass,true,true) was successful and stored during VP, we need to test again the real arrayComponentClass
      // Need to relocate address of arrayComponentClass under aot sharedcache
      // Need to possibility of class unloading.
      // --------------------------------------------


      if (!(comp->getOption(TR_DisableArrayStoreCheckOpts)) && node->getArrayComponentClassInNode() )
         {
         TR_OpaqueClassBlock *arrayComponentClass = (TR_OpaqueClassBlock *) node->getArrayComponentClassInNode();
         if (comp->target().is64Bit())
            {
            if (TR::Compiler->om.compressObjectReferences())
               {
               TR_ASSERT((((uintptr_t)arrayComponentClass) >> 32) == 0, "TR_OpaqueClassBlock must fit on 32 bits when using class pointer compression");
               instr = generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, destComponentClassReg, (uint32_t) ((uint64_t) arrayComponentClass), cg);

               if (fej9->isUnloadAssumptionRequired(arrayComponentClass, comp->getCurrentMethod()))
                            comp->getStaticPICSites()->push_front(instr);

               }
            else // 64 bit but no class pointer compression
               {
               if ((uintptr_t)arrayComponentClass <= (uintptr_t)0x7fffffff)
                  {
                  instr = generateRegImmInstruction(TR::InstOpCode::CMP8RegImm4, node, destComponentClassReg, (uintptr_t) arrayComponentClass, cg);
                  if (fej9->isUnloadAssumptionRequired(arrayComponentClass, comp->getCurrentMethod()))
                     comp->getStaticPICSites()->push_front(instr);

                  }
               else
                  {
                  TR::Register *arrayComponentClassReg = scratchRegisterManager->findOrCreateScratchRegister();
                  instr = generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, arrayComponentClassReg, (uintptr_t) arrayComponentClass, cg);
                  generateRegRegInstruction(TR::InstOpCode::CMP8RegReg, node, destComponentClassReg, arrayComponentClassReg, cg);
                  scratchRegisterManager->reclaimScratchRegister(arrayComponentClassReg);
                  }
               }
            }
         else
            {
            instr = generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, destComponentClassReg, (int32_t)(uintptr_t) arrayComponentClass, cg);
            if (fej9->isUnloadAssumptionRequired(arrayComponentClass, comp->getCurrentMethod()))
               comp->getStaticPICSites()->push_front(instr);

            }

         generateLabelInstruction(TR::InstOpCode::JE4, node, wrtbarLabel, cg);
         }




   // For compressed references:
   // destComponentClassReg contains the class offset so we may need to generate code
   // to convert from class offset to real J9Class pointer

      // -------------------------------------------------------------------------
      //
      // Compare source and dest class depths
      //
      // -------------------------------------------------------------------------

      // Get the depth of array component type in testerReg
      //
      bool eliminateDepthMask = (J9AccClassDepthMask == 0xffff);
      TR::MemoryReference *destComponentClassDepthMR =
         generateX86MemoryReference(destComponentClassReg, offsetof(J9Class,classDepthAndFlags), cg);

      // DMDM  32-bit only???
      if (comp->target().is32Bit())
         {
         scratchRegisterManager->reclaimScratchRegister(destComponentClassReg);
         }

      TR::Register *destComponentClassDepthReg = scratchRegisterManager->findOrCreateScratchRegister();

      if (eliminateDepthMask)
         {
         if (comp->target().is64Bit())
            generateRegMemInstruction(TR::InstOpCode::MOVZXReg8Mem2, node, destComponentClassDepthReg, destComponentClassDepthMR, cg);
         else
            generateRegMemInstruction(TR::InstOpCode::MOVZXReg4Mem2, node, destComponentClassDepthReg, destComponentClassDepthMR, cg);
         }
      else
         {
         generateRegMemInstruction(
            TR::InstOpCode::LRegMem(),
            node,
            destComponentClassDepthReg,
            destComponentClassDepthMR, cg);
         }

      if (!eliminateDepthMask)
         {
         if (comp->target().is64Bit())
            {
            TR_ASSERT(!(J9AccClassDepthMask & 0x80000000), "AMD64: need to use a second register for AND mask");
            if (!(J9AccClassDepthMask & 0x80000000))
               generateRegImmInstruction(TR::InstOpCode::AND8RegImm4, node, destComponentClassDepthReg, J9AccClassDepthMask, cg);
            }
         else
            {
            generateRegImmInstruction(TR::InstOpCode::AND4RegImm4, node, destComponentClassDepthReg, J9AccClassDepthMask, cg);
            }
         }

   // For compressed references:
   // temp2 contains the class offset so we may need to generate code
   // to convert from class offset to real J9Class pointer

      // Get the depth of type of object being stored into the array in testerReg2
      //

      TR::MemoryReference *mr = generateX86MemoryReference(sourceClassReg, offsetof(J9Class,classDepthAndFlags), cg);

      // There aren't enough registers available on 32-bit across this internal
      // control flow region.  Give one back and manually and force the source
      // class to be rematerialized later.
      //
      if (comp->target().is32Bit())
         {
         scratchRegisterManager->reclaimScratchRegister(sourceClassReg);
         }

       TR::Register *sourceClassDepthReg = NULL;
       if (eliminateDepthMask)
         {
         generateMemRegInstruction(TR::InstOpCode::CMP2MemReg, node, mr, destComponentClassDepthReg, cg);
         }
       else
         {
         sourceClassDepthReg = scratchRegisterManager->findOrCreateScratchRegister();
         generateRegMemInstruction(
            TR::InstOpCode::LRegMem(),
            node,
            sourceClassDepthReg,
            mr, cg);

         if (comp->target().is64Bit())
            {
            TR_ASSERT(!(J9AccClassDepthMask & 0x80000000), "AMD64: need to use a second register for AND mask");
            if (!(J9AccClassDepthMask & 0x80000000))
               generateRegImmInstruction(TR::InstOpCode::AND8RegImm4, node, sourceClassDepthReg, J9AccClassDepthMask, cg);
            }
         else
            {
            generateRegImmInstruction(TR::InstOpCode::AND4RegImm4, node, sourceClassDepthReg, J9AccClassDepthMask, cg);
            }
         generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, sourceClassDepthReg, destComponentClassDepthReg, cg);
         }

      /*TR::Register *sourceClassDepthReg = scratchRegisterManager->findOrCreateScratchRegister();
      generateRegMemInstruction(
         TR::InstOpCode::LRegMem(),
         node,
         sourceClassDepthReg,
         mr, cg);

      if (comp->target().is64Bit())
         {
         TR_ASSERT(!(J9AccClassDepthMask & 0x80000000), "AMD64: need to use a second register for AND mask");
         if (!(J9AccClassDepthMask & 0x80000000))
            generateRegImmInstruction(TR::InstOpCode::AND8RegImm4, node, sourceClassDepthReg, J9AccClassDepthMask, cg);
         }
      else
         {
         generateRegImmInstruction(TR::InstOpCode::AND4RegImm4, node, sourceClassDepthReg, J9AccClassDepthMask, cg);
         }

      generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, sourceClassDepthReg, destComponentClassDepthReg, cg);*/

      generateLabelInstruction(TR::InstOpCode::JBE4, node, helperCallLabel, cg);
      if (sourceClassDepthReg != NULL)
         scratchRegisterManager->reclaimScratchRegister(sourceClassDepthReg);


   // For compressed references:
   // destComponentClassReg contains the class offset so we may need to generate code
   // to convert from class offset to real J9Class pointer

      if (comp->target().is32Bit())
         {
         // Rematerialize the source class.
         //
         sourceClassReg = scratchRegisterManager->findOrCreateScratchRegister();
         TR::MemoryReference *sourceClassMR = generateX86MemoryReference(sourceReg, TR::Compiler->om.offsetOfObjectVftField(), cg);
         generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, sourceClassReg, sourceClassMR, cg);
         TR::TreeEvaluator::generateVFTMaskInstruction(node, sourceClassReg, cg);
         }

      TR::MemoryReference *tempMR = generateX86MemoryReference(sourceClassReg, offsetof(J9Class,superclasses), cg);

      if (comp->target().is32Bit())
         {
         scratchRegisterManager->reclaimScratchRegister(sourceClassReg);
         }

      TR::Register *sourceSuperClassReg = scratchRegisterManager->findOrCreateScratchRegister();

      generateRegMemInstruction(
         TR::InstOpCode::LRegMem(),
         node,
         sourceSuperClassReg,
         tempMR,
         cg);

      TR::MemoryReference *leaMR =
         generateX86MemoryReference(sourceSuperClassReg, destComponentClassDepthReg, logBase2(sizeof(uintptr_t)), 0, cg);

      // For compressed references:
      // leaMR is a memory reference to a J9Class
      // destComponentClassReg contains a TR_OpaqueClassBlock
      // We may need to convert superClass to a class offset before doing the comparison

      if (comp->target().is32Bit())
         {

         generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, sourceSuperClassReg, leaMR, cg);

         // Rematerialize destination component class
         //
         TR::MemoryReference *destClassMR = generateX86MemoryReference(destReg, TR::Compiler->om.offsetOfObjectVftField(), cg);

         generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, destComponentClassReg, destClassMR, cg);
         TR::TreeEvaluator::generateVFTMaskInstruction(node, destComponentClassReg, cg);
         TR::MemoryReference *destCompTypeMR =
            generateX86MemoryReference(destComponentClassReg, offsetof(J9ArrayClass, componentType), cg);

         generateMemRegInstruction(TR::InstOpCode::CMPMemReg(), node, destCompTypeMR, sourceSuperClassReg, cg);
         }
      else
         {
         generateRegMemInstruction(TR::InstOpCode::CMP4RegMem, node, destComponentClassReg, leaMR, cg);
         }

      scratchRegisterManager->reclaimScratchRegister(destComponentClassReg);
      scratchRegisterManager->reclaimScratchRegister(destComponentClassDepthReg);
      scratchRegisterManager->reclaimScratchRegister(sourceClassReg);
      scratchRegisterManager->reclaimScratchRegister(sourceSuperClassReg);

      generateLabelInstruction(TR::InstOpCode::JE4, node, wrtbarLabel, cg);
      }

   // The fast paths failed; execute the type-check helper call.
   //
   TR::LabelSymbol* helperReturnLabel = generateLabelSymbol(cg);
   TR::Node *helperCallNode = TR::Node::createWithSymRef(TR::call, 2, 2, sourceChild, destinationChild, node->getSymbolReference());
   helperCallNode->copyByteCodeInfo(node);
   generateLabelInstruction(TR::InstOpCode::JMP4, helperCallNode, helperCallLabel, cg);
   TR_OutlinedInstructions* outlinedHelperCall = new (cg->trHeapMemory()) TR_OutlinedInstructions(helperCallNode, TR::call, NULL, helperCallLabel, helperReturnLabel, cg);
   cg->getOutlinedInstructionsList().push_front(outlinedHelperCall);
   generateLabelInstruction(TR::InstOpCode::label, helperCallNode, helperReturnLabel, cg);
   cg->decReferenceCount(sourceChild);
   cg->decReferenceCount(destinationChild);
   }


// Check that two objects are compatible for use in an arraycopy operation.
// If not, an ArrayStoreException is thrown.
//
TR::Register *J9::X86::TreeEvaluator::VMarrayCheckEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());
   bool use64BitClasses = cg->comp()->target().is64Bit() && !TR::Compiler->om.generateCompressedObjectHeaders();

   TR::Node     *object1    = node->getFirstChild();
   TR::Node     *object2    = node->getSecondChild();
   TR::Register *object1Reg = cg->evaluate(object1);
   TR::Register *object2Reg = cg->evaluate(object2);

   TR::LabelSymbol *startLabel   = generateLabelSymbol(cg);
   TR::LabelSymbol *fallThrough  = generateLabelSymbol(cg);
   TR::Instruction *instr;
   TR::LabelSymbol *snippetLabel = NULL;
   TR::Snippet     *snippet      = NULL;
   TR::Register    *tempReg      = cg->allocateRegister();

   startLabel->setStartInternalControlFlow();
   fallThrough->setEndInternalControlFlow();
   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

   // If the objects are the same and one of them is known to be an array, they
   // are compatible.
   //
   if (node->isArrayChkPrimitiveArray1() ||
       node->isArrayChkReferenceArray1() ||
       node->isArrayChkPrimitiveArray2() ||
       node->isArrayChkReferenceArray2())
      {
      generateRegRegInstruction(TR::InstOpCode::CMPRegReg(), node, object1Reg, object2Reg, cg);
      generateLabelInstruction(TR::InstOpCode::JE4, node, fallThrough, cg);
      }

   else
      {
      // Neither object is known to be an array
      // Check that object 1 is an array. If not, throw exception.
      //
      TR::InstOpCode::Mnemonic testOpCode;
      if ((J9AccClassRAMArray >= CHAR_MIN) && (J9AccClassRAMArray <= CHAR_MAX))
         testOpCode = TR::InstOpCode::TEST1MemImm1;
      else
         testOpCode = TR::InstOpCode::TEST4MemImm4;

      if (TR::Compiler->om.compressObjectReferences())
         generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, tempReg, generateX86MemoryReference(object1Reg,  TR::Compiler->om.offsetOfObjectVftField(), cg), cg);
      else
         generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, tempReg, generateX86MemoryReference(object1Reg,  TR::Compiler->om.offsetOfObjectVftField(), cg), cg);

      TR::TreeEvaluator::generateVFTMaskInstruction(node, tempReg, cg);
      generateMemImmInstruction(testOpCode, node, generateX86MemoryReference(tempReg,  offsetof(J9Class, classDepthAndFlags), cg), J9AccClassRAMArray, cg);
      if (!snippetLabel)
         {
         snippetLabel = generateLabelSymbol(cg);
         instr        = generateLabelInstruction(TR::InstOpCode::JE4, node, snippetLabel, cg);
         snippet      = new (cg->trHeapMemory()) TR::X86CheckFailureSnippet(cg, node->getSymbolReference(), snippetLabel, instr);
         cg->addSnippet(snippet);
         }
      else
         generateLabelInstruction(TR::InstOpCode::JE4, node, snippetLabel, cg);
      }

   // Test equality of the object classes.
   //
   generateRegMemInstruction(TR::InstOpCode::LRegMem(use64BitClasses), node, tempReg, generateX86MemoryReference(object1Reg, TR::Compiler->om.offsetOfObjectVftField(), cg), cg);
   generateRegMemInstruction(TR::InstOpCode::XORRegMem(use64BitClasses), node, tempReg, generateX86MemoryReference(object2Reg, TR::Compiler->om.offsetOfObjectVftField(), cg), cg);
   TR::TreeEvaluator::generateVFTMaskInstruction(node, tempReg, cg);

   // If either object is known to be a primitive array, we are done. Either
   // the equality test fails and we throw the exception or it succeeds and
   // we finish.
   //
   if (node->isArrayChkPrimitiveArray1() || node->isArrayChkPrimitiveArray2())
      {
      if (!snippetLabel)
         {
         snippetLabel = generateLabelSymbol(cg);
         instr        = generateLabelInstruction(TR::InstOpCode::JNE4, node, snippetLabel, cg);
         snippet      = new (cg->trHeapMemory()) TR::X86CheckFailureSnippet(cg, node->getSymbolReference(), snippetLabel, instr);
         cg->addSnippet(snippet);
         }
      else
         generateLabelInstruction(TR::InstOpCode::JNE4, node, snippetLabel, cg);
      }

   // Otherwise, there is more testing to do. If the classes are equal we
   // are done, and branch to the fallThrough label.
   //
   else
      {
      generateLabelInstruction(TR::InstOpCode::JE4, node, fallThrough, cg);

      // If either object is not known to be a reference array type, check it
      // We already know that object1 is an array type but we may have to now
      // check object2.
      //
      if (!node->isArrayChkReferenceArray1())
         {

         if (TR::Compiler->om.compressObjectReferences())
            generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, tempReg, generateX86MemoryReference(object1Reg,  TR::Compiler->om.offsetOfObjectVftField(), cg), cg);
         else
            generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, tempReg, generateX86MemoryReference(object1Reg,  TR::Compiler->om.offsetOfObjectVftField(), cg), cg);

         TR::TreeEvaluator::generateVFTMaskInstruction(node, tempReg, cg);
         generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, tempReg, generateX86MemoryReference(tempReg, offsetof(J9Class, classDepthAndFlags), cg), cg);
         // X = (ramclass->ClassDepthAndFlags)>>J9AccClassRAMShapeShift

         // X & OBJECT_HEADER_SHAPE_MASK
         generateRegImmInstruction(TR::InstOpCode::ANDRegImm4(), node, tempReg, (OBJECT_HEADER_SHAPE_MASK << J9AccClassRAMShapeShift), cg);
         generateRegImmInstruction(TR::InstOpCode::CMPRegImm4(), node, tempReg, (OBJECT_HEADER_SHAPE_POINTERS << J9AccClassRAMShapeShift), cg);

         if (!snippetLabel)
            {
            snippetLabel = generateLabelSymbol(cg);
            instr        = generateLabelInstruction(TR::InstOpCode::JNE4, node, snippetLabel, cg);
            snippet      = new (cg->trHeapMemory()) TR::X86CheckFailureSnippet(cg, node->getSymbolReference(), snippetLabel, instr);
            cg->addSnippet(snippet);
            }
         else
            generateLabelInstruction(TR::InstOpCode::JNE4, node, snippetLabel, cg);
         }
      if (!node->isArrayChkReferenceArray2())
         {
         // Check that object 2 is an array. If not, throw exception.
         //
         TR::InstOpCode::Mnemonic testOpCode;
         if ((J9AccClassRAMArray >= CHAR_MIN) && (J9AccClassRAMArray <= CHAR_MAX))
            testOpCode = TR::InstOpCode::TEST1MemImm1;
         else
            testOpCode = TR::InstOpCode::TEST4MemImm4;

         // Check that object 2 is an array. If not, throw exception.
         //
         if (TR::Compiler->om.compressObjectReferences())
            generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, tempReg, generateX86MemoryReference(object2Reg,  TR::Compiler->om.offsetOfObjectVftField(), cg), cg);
         else
            generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, tempReg, generateX86MemoryReference(object2Reg,  TR::Compiler->om.offsetOfObjectVftField(), cg), cg);
         TR::TreeEvaluator::generateVFTMaskInstruction(node, tempReg, cg);
         generateMemImmInstruction(testOpCode, node, generateX86MemoryReference(tempReg,  offsetof(J9Class, classDepthAndFlags), cg), J9AccClassRAMArray, cg);
         if (!snippetLabel)
            {
            snippetLabel = generateLabelSymbol(cg);
            instr        = generateLabelInstruction(TR::InstOpCode::JE4, node, snippetLabel, cg);
            snippet      = new (cg->trHeapMemory()) TR::X86CheckFailureSnippet(cg, node->getSymbolReference(), snippetLabel, instr);
            cg->addSnippet(snippet);
            }
         else
            generateLabelInstruction(TR::InstOpCode::JE4, node, snippetLabel, cg);

         generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, tempReg, generateX86MemoryReference(tempReg, offsetof(J9Class, classDepthAndFlags), cg), cg);
         generateRegImmInstruction(TR::InstOpCode::ANDRegImm4(), node, tempReg, (OBJECT_HEADER_SHAPE_MASK << J9AccClassRAMShapeShift), cg);
         generateRegImmInstruction(TR::InstOpCode::CMPRegImm4(), node, tempReg, (OBJECT_HEADER_SHAPE_POINTERS << J9AccClassRAMShapeShift), cg);

         generateLabelInstruction(TR::InstOpCode::JNE4, node, snippetLabel, cg);
         }

      // Now both objects are known to be reference arrays, so they are
      // compatible for arraycopy.
      }

   // Now generate the fall-through label
   //
   TR::RegisterDependencyConditions  *deps = generateRegisterDependencyConditions((uint8_t)0, (uint8_t)4, cg);
   deps->addPostCondition(object1Reg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(object2Reg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(tempReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(cg->getVMThreadRegister(), TR::RealRegister::ebp, cg);

   generateLabelInstruction(TR::InstOpCode::label, node, fallThrough, deps, cg);

   cg->stopUsingRegister(tempReg);
   cg->decReferenceCount(object1);
   cg->decReferenceCount(object2);

   return NULL;
   }


#ifdef LINUX
#if defined(TR_TARGET_32BIT)
static void
addFPXMMDependencies(
      TR::CodeGenerator *cg,
      TR::RegisterDependencyConditions *dependencies)
   {
   TR_LiveRegisters *lr = cg->getLiveRegisters(TR_FPR);
   if (!lr || lr->getNumberOfLiveRegisters() > 0)
      {
      for (int regIndex = TR::RealRegister::FirstXMMR; regIndex <= TR::RealRegister::LastXMMR; regIndex++)
         {
         TR::Register *dummy = cg->allocateRegister(TR_FPR);
         dummy->setPlaceholderReg();
         dependencies->addPostCondition(dummy, (TR::RealRegister::RegNum)regIndex, cg);
         cg->stopUsingRegister(dummy);
         }
      }
   }
#endif

#define J9TIME_NANOSECONDS_PER_SECOND ((I_64) 1000000000)
#if defined(TR_TARGET_64BIT)
static bool
inlineNanoTime(
      TR::Node *node,
      TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(comp->fe());

   if (debug("traceInlInlining"))
      diagnostic("nanoTime called by %s\n", comp->signature());

   if (fej9->supportsFastNanoTime())
      {  // Fully Inlined Version

      // First, evaluate resultAddress if provided.  There's no telling how
      // many regs that address computation needs, so let's get it out of the
      // way before we start using registers for other things.
      //

      TR::Register *resultAddress;
      if (node->getNumChildren() == 1)
         {
         resultAddress = cg->evaluate(node->getFirstChild());
         }
      else
         {
         TR_ASSERT(node->getNumChildren() == 0, "nanoTime must have zero or one children");
         resultAddress = NULL;
         }

      TR::SymbolReference *gtod = comp->getSymRefTab()->findOrCreateRuntimeHelper(TR_AMD64clockGetTime);
      TR::Node *timevalNode = TR::Node::createWithSymRef(node, TR::loadaddr, 0, cg->getNanoTimeTemp());
      TR::Node *clockSourceNode = TR::Node::create(node, TR::iconst, 0, CLOCK_MONOTONIC);
      TR::Node *callNode    = TR::Node::createWithSymRef(TR::call, 2, 2, clockSourceNode, timevalNode, gtod);
      // TODO: Use performCall
      TR::Linkage *linkage = cg->getLinkage(gtod->getSymbol()->getMethodSymbol()->getLinkageConvention());
      linkage->buildDirectDispatch(callNode, false);

      TR::Register *result  = cg->allocateRegister();
      TR::Register *reg     = cg->allocateRegister();

      TR::MemoryReference *tv_sec;

      // result = tv_sec * 1,000,000,000 (converts seconds to nanoseconds)

      tv_sec = generateX86MemoryReference(timevalNode, cg, false);
      generateRegMemInstruction(TR::InstOpCode::L8RegMem, node, result, tv_sec, cg);
      generateRegRegImmInstruction(TR::InstOpCode::IMUL8RegRegImm4, node, result, result, J9TIME_NANOSECONDS_PER_SECOND, cg);

      // reg = tv_usec
      generateRegMemInstruction(TR::InstOpCode::L8RegMem, node, reg, generateX86MemoryReference(*tv_sec, offsetof(struct timespec, tv_nsec), cg), cg);

      // result = reg + result
      generateRegMemInstruction(TR::InstOpCode::LEA8RegMem, node, result, generateX86MemoryReference(reg, result, 0, cg), cg);

#if defined(J9VM_OPT_CRIU_SUPPORT)
      if (fej9->isSnapshotModeEnabled())
         {
         // result = result - nanoTimeMonotonicClockDelta
         TR::Register *vmThreadReg = cg->getVMThreadRegister();
         generateRegMemInstruction(TR::InstOpCode::L8RegMem, node, reg, generateX86MemoryReference(vmThreadReg, offsetof(J9VMThread, javaVM), cg), cg);
         generateRegMemInstruction(TR::InstOpCode::L8RegMem, node, reg, generateX86MemoryReference(reg, offsetof(J9JavaVM, portLibrary), cg), cg);
         generateRegMemInstruction(TR::InstOpCode::SUB8RegMem, node, result, generateX86MemoryReference(reg, offsetof(J9PortLibrary, nanoTimeMonotonicClockDelta), cg), cg);
         }
#endif /* defined(J9VM_OPT_CRIU_SUPPORT) */

      cg->stopUsingRegister(reg);

      // Store the result to memory if necessary
      if (resultAddress)
         {
         generateMemRegInstruction(TR::InstOpCode::S8MemReg, node, generateX86MemoryReference(resultAddress, 0, cg), result, cg);

         cg->decReferenceCount(node->getFirstChild());
         if (node->getReferenceCount() == 1 && cg->getCurrentEvaluationTreeTop()->getNode()->getOpCodeValue() == TR::treetop)
            {
            // Result is not needed in a register, so free it up
            //
            cg->stopUsingRegister(result);
            result = NULL;
            }
         }

      node->setRegister(result);

      return true;
      }
   else
      {  // Inlined call to Port Library
      return false;
      }
   }
#else // !64bit
static bool
inlineNanoTime(
      TR::Node *node,
      TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(comp->fe());

   if (debug("traceInlInlining"))
      diagnostic("nanoTime called by %s\n", comp->signature());

   TR::RealRegister  *espReal = cg->machine()->getRealRegister(TR::RealRegister::esp);
   TR::Register *vmThreadReg = cg->getVMThreadRegister();
   TR::Register *temp2 = 0;

   if (fej9->supportsFastNanoTime())
      {
      TR::Register *resultAddress;
      if (node->getNumChildren() == 1)
         {
         resultAddress = cg->evaluate(node->getFirstChild());
         generateRegInstruction(TR::InstOpCode::PUSHReg,  node, resultAddress, cg);
         generateImmInstruction(TR::InstOpCode::PUSHImm4, node, CLOCK_MONOTONIC, cg);
         }
      else
         {
         // Leave space on the stack for the 64-bit result
         //

         generateRegImmInstruction(TR::InstOpCode::SUB4RegImms, node, espReal, 8, cg);

         resultAddress = cg->allocateRegister();
         generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, resultAddress, espReal, cg); // save away esp before the push
         generateRegInstruction(TR::InstOpCode::PUSHReg,  node, resultAddress, cg);
         generateImmInstruction(TR::InstOpCode::PUSHImm4, node, CLOCK_MONOTONIC, cg);
         cg->stopUsingRegister(resultAddress);
         resultAddress = espReal;
         }

      // 64-bit issues on the call instructions below

      // Build register dependencies and call the method in the system library
      // directly. Since this is a "C"-style call, ebx, esi and edi are preserved
      //
      int32_t extraFPDeps = (uint8_t)(TR::RealRegister::LastXMMR - TR::RealRegister::FirstXMMR+1);
      TR::RegisterDependencyConditions  *deps = generateRegisterDependencyConditions((uint8_t)0, (uint8_t)4 + extraFPDeps, cg);
      TR::Register *temp1 = cg->allocateRegister();
      deps->addPostCondition(temp1, TR::RealRegister::eax, cg);
      cg->stopUsingRegister(temp1);
      temp1 = cg->allocateRegister();
      deps->addPostCondition(temp1, TR::RealRegister::ecx, cg);
      cg->stopUsingRegister(temp1);
      temp1 = cg->allocateRegister();
      deps->addPostCondition(temp1, TR::RealRegister::edx, cg);
      cg->stopUsingRegister(temp1);
      deps->addPostCondition(cg->getMethodMetaDataRegister(), TR::RealRegister::ebp, cg);

      // add the XMM dependencies
      addFPXMMDependencies(cg, deps);
      deps->stopAddingConditions();

      TR::X86ImmInstruction  *callInstr = generateImmInstruction(TR::InstOpCode::CALLImm4, node, (int32_t)&clock_gettime, deps, cg);

      generateRegImmInstruction(TR::InstOpCode::ADD4RegImms, node, espReal, 8, cg);

      TR::Register *eaxReal = cg->allocateRegister();
      TR::Register *edxReal = cg->allocateRegister();

      // load usec to a register
      TR::Register *reglow = cg->allocateRegister();
      generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, reglow, generateX86MemoryReference(resultAddress, 4, cg), cg);


      TR::RegisterDependencyConditions  *dep1 = generateRegisterDependencyConditions((uint8_t)2, 2, cg);
      dep1->addPreCondition(eaxReal, TR::RealRegister::eax, cg);
      dep1->addPreCondition(edxReal, TR::RealRegister::edx, cg);
      dep1->addPostCondition(eaxReal, TR::RealRegister::eax, cg);
      dep1->addPostCondition(edxReal, TR::RealRegister::edx, cg);


      // load second to eax then multiply by 1,000,000,000

      generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, edxReal, generateX86MemoryReference(resultAddress, 0, cg), cg);
      generateRegImmInstruction(TR::InstOpCode::MOV4RegImm4, node, eaxReal, J9TIME_NANOSECONDS_PER_SECOND, cg);
      generateRegRegInstruction(TR::InstOpCode::IMUL4AccReg, node, eaxReal, edxReal, dep1, cg);


      // add the two parts
      generateRegRegInstruction(TR::InstOpCode::ADD4RegReg, node, eaxReal, reglow, cg);
      generateRegImmInstruction(TR::InstOpCode::ADC4RegImm4, node, edxReal, 0x0, cg);

#if defined(J9VM_OPT_CRIU_SUPPORT)
      if (fej9->isSnapshotModeEnabled())
         {
         // subtract nanoTimeMonotonicClockDelta from the result
         TR::Register *vmThreadReg = cg->getVMThreadRegister();
         generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, regLow, generateX86MemoryReference(vmThreadReg, offsetof(J9VMThread, javaVM), cg), cg);
         generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, regLow, generateX86MemoryReference(regLow, offsetof(J9JavaVM, portLibrary), cg), cg);
         generateRegMemInstruction(TR::InstOpCode::SUB4RegMem, node, eaxReal, generateX86MemoryReference(regLow, offsetof(J9PortLibrary, nanoTimeMonotonicClockDelta), cg), cg);
         generateRegMemInstruction(TR::InstOpCode::SBB4RegMem, node, edxReal, generateX86MemoryReference(regLow, offsetof(J9PortLibrary, nanoTimeMonotonicClockDelta) + 4, cg), cg);
         }
#endif /* defined(J9VM_OPT_CRIU_SUPPORT) */

      // store it back
      generateMemRegInstruction(TR::InstOpCode::S4MemReg, node, generateX86MemoryReference(resultAddress, 0, cg), eaxReal, cg);
      generateMemRegInstruction(TR::InstOpCode::S4MemReg, node, generateX86MemoryReference(resultAddress, 4, cg), edxReal, cg);

      cg->stopUsingRegister(eaxReal);
      cg->stopUsingRegister(edxReal);
      cg->stopUsingRegister(reglow);

      TR::Register *lowReg = cg->allocateRegister();
      TR::Register *highReg = cg->allocateRegister();

      if (node->getNumChildren() == 1)
         {
         if (node->getReferenceCount() > 1 ||
             cg->getCurrentEvaluationTreeTop()->getNode()->getOpCodeValue() != TR::treetop)
            {
            generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, lowReg, generateX86MemoryReference(resultAddress, 0, cg), cg);
            generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, highReg, generateX86MemoryReference(resultAddress, 4, cg), cg);

            TR::RegisterPair *result  = cg->allocateRegisterPair(lowReg, highReg);
            node->setRegister(result);
            }
         cg->decReferenceCount(node->getFirstChild());
         }
      else
         {
         // The result of the call is now on the stack. Get it into registers.
         //
         generateRegInstruction(TR::InstOpCode::POPReg, node, lowReg, cg);
         generateRegInstruction(TR::InstOpCode::POPReg, node, highReg, cg);
         TR::RegisterPair *result = cg->allocateRegisterPair(lowReg, highReg);
         node->setRegister(result);
         }
      }
   else
      {
      // This code is busted. The hires clock is measured in microseconds, not
      // nanoseconds, and this code doesn't correct for that. The above code
      // will be faster anyway, and it should be upgraded to support AOT, so
      // then we'll never need the hires clock version again.
      static char *useHiResClock = feGetEnv("TR_useHiResClock");
      if (!useHiResClock)
         return false;
      // Leave space on the stack for the 64-bit result
      //
      temp2 = cg->allocateRegister();
      generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, temp2, generateX86MemoryReference(vmThreadReg, offsetof(J9VMThread, javaVM), cg), cg);
      generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, temp2, generateX86MemoryReference(temp2, offsetof(J9JavaVM, portLibrary), cg), cg);
      generateRegInstruction(TR::InstOpCode::PUSHReg, node, espReal, cg);
      generateRegInstruction(TR::InstOpCode::PUSHReg, node, temp2, cg);

      int32_t extraFPDeps = (uint8_t)(TR::RealRegister::LastXMMR - TR::RealRegister::FirstXMMR+1);

      // Build register dependencies and call the method in the port library
      // directly. Since this is a "C"-style call, ebx, esi and edi are preserved
      //
      TR::RegisterDependencyConditions  *deps = generateRegisterDependencyConditions((uint8_t)0, (uint8_t)4 + extraFPDeps, cg);
      TR::Register *temp1 = cg->allocateRegister();
      deps->addPostCondition(temp1, TR::RealRegister::ecx, cg);
      cg->stopUsingRegister(temp1);

      TR::Register *lowReg = cg->allocateRegister();
      deps->addPostCondition(lowReg, TR::RealRegister::eax, cg);

      TR::Register *highReg = cg->allocateRegister();
      deps->addPostCondition(highReg, TR::RealRegister::edx, cg);

      deps->addPostCondition(cg->getMethodMetaDataRegister(), TR::RealRegister::ebp, cg);

      // add the XMM dependencies
      addFPXMMDependencies(cg, deps);
      deps->stopAddingConditions();

      generateCallMemInstruction(TR::InstOpCode::CALLMem, node, generateX86MemoryReference(temp2, offsetof(OMRPortLibrary, time_hires_clock), cg), deps, cg);
      cg->stopUsingRegister(temp2);

      generateRegImmInstruction(TR::InstOpCode::ADD4RegImms, node, espReal, 8, cg);

      TR::RegisterPair *result = cg->allocateRegisterPair(lowReg, highReg);
      node->setRegister(result);
      }

   return true;
   }
#endif
#endif // LINUX

TR::Register* J9::X86::TreeEvaluator::inlineMathFma(TR::Node* node, TR::CodeGenerator* cg)
   {
   TR::Node *firstChild = node->getFirstChild();
   TR::Node *secondChild = node->getSecondChild();
   TR::Node *thirdChild = node->getThirdChild();

   TR::Register *lhsReg = NULL;
   TR::Register *midReg = NULL;
   TR::Register *rhsReg = NULL;
   TR::Register *result = cg->allocateRegister(TR_FPR);

   bool memLoadLhs = !firstChild->getRegister() && firstChild->getReferenceCount() == 1
                     && firstChild->getOpCode().isLoadVar();

   bool memLoadMiddle = !secondChild->getRegister() && secondChild->getReferenceCount() == 1
                        && secondChild->getOpCode().isLoadVar();

   bool memLoadRhs = !thirdChild->getRegister() && thirdChild->getReferenceCount() == 1
                     && thirdChild->getOpCode().isLoadVar();

   bool is64Bit = node->getDataType().isDouble();

   TR::InstOpCode::Mnemonic fpMovRegRegOpcode = is64Bit ? TR::InstOpCode::MOVSDRegReg : TR::InstOpCode::MOVSSRegReg;
   result->setIsSinglePrecision(!is64Bit);

   TR_ASSERT_FATAL(cg->comp()->target().cpu.supportsFeature(OMR_FEATURE_X86_FMA), "Cannot generate inline fma implementation without FMA extensions");

   // Choose fma instruction carefully, based on operand form, to reduce number of copies
   if (memLoadLhs)
      {
      TR::InstOpCode::Mnemonic opcode = is64Bit ? TR::InstOpCode::VFMADD231SDRegRegMem : TR::InstOpCode::VFMADD231SSRegRegMem;
      TR::MemoryReference *lhsMR = generateX86MemoryReference(firstChild, cg);

      if (memLoadRhs)
         {
         // a (2) * b (3) + c (1)
         TR::MemoryReference *rhsMR = generateX86MemoryReference(thirdChild, cg);
         generateRegMemInstruction(TR::InstOpCode::MOVSRegMem(is64Bit), node, result, rhsMR, cg);

         midReg = cg->evaluate(secondChild);
         memLoadMiddle = false; // No choice but to evaluate;
         generateRegRegMemInstruction(opcode, node, result, midReg, lhsMR, cg);
         }
      else if (memLoadMiddle)
         {
         // fma = a (1) * b (3) + c (2)
         opcode = is64Bit ? TR::InstOpCode::VFMADD132SDRegRegMem : TR::InstOpCode::VFMADD132SSRegRegMem;

         TR::MemoryReference *midMR = generateX86MemoryReference(secondChild, cg);
         rhsReg = cg->evaluate(thirdChild);

         generateRegMemInstruction(TR::InstOpCode::MOVSRegMem(is64Bit), node, result, lhsMR, cg);
         generateRegRegMemInstruction(opcode, node, result, rhsReg, midMR, cg);
         }
      else
         {
         // fma = a (2) * b (3) + c (1)
         midReg = cg->evaluate(secondChild);
         rhsReg = cg->evaluate(thirdChild);
         generateRegRegInstruction(fpMovRegRegOpcode, node, result, rhsReg, cg);
         generateRegRegMemInstruction(opcode, node, result, midReg, lhsMR, cg);
         }
      }
   else if (memLoadMiddle)
      {
      TR::MemoryReference *midMR = generateX86MemoryReference(secondChild, cg);
      lhsReg = cg->evaluate(firstChild);

      if (memLoadRhs)
         {
         // fma = a (2) * b (1) + c (3)
         TR::InstOpCode::Mnemonic opcode = is64Bit ? TR::InstOpCode::VFMADD213SDRegRegMem : TR::InstOpCode::VFMADD213SSRegRegMem;
         TR::MemoryReference *rhsMR = generateX86MemoryReference(thirdChild, cg);

         generateRegMemInstruction(TR::InstOpCode::MOVSRegMem(is64Bit), node, result, midMR, cg);
         generateRegRegMemInstruction(opcode, node, result, lhsReg, rhsMR, cg);
         }
      else
         {
         // fma = a (1) * b (3) + c (2)
         TR::InstOpCode::Mnemonic opcode = is64Bit ? TR::InstOpCode::VFMADD132SDRegRegMem : TR::InstOpCode::VFMADD132SSRegRegMem;
         rhsReg = cg->evaluate(thirdChild);

         generateRegRegInstruction(fpMovRegRegOpcode, node, result, lhsReg, cg);
         generateRegRegMemInstruction(opcode, node, result, rhsReg, midMR, cg);
         }
      }
   else if (memLoadRhs)
      {
      // fma = a (2) * b (1) + c (3)
      TR::InstOpCode::Mnemonic opcode = is64Bit ? TR::InstOpCode::VFMADD213SDRegRegMem : TR::InstOpCode::VFMADD213SSRegRegMem;

      TR::MemoryReference *rhsMR = generateX86MemoryReference(thirdChild, cg);
      lhsReg = cg->evaluate(firstChild);
      midReg = cg->evaluate(secondChild);

      generateRegRegInstruction(fpMovRegRegOpcode, node, result, lhsReg, cg);
      generateRegRegMemInstruction(opcode, node, result, midReg, rhsMR, cg);
      }
   else
      {
      // fma = a (2) * b (1) + c (3)
      TR::InstOpCode::Mnemonic opcode = is64Bit ? TR::InstOpCode::VFMADD213SDRegRegReg : TR::InstOpCode::VFMADD213SSRegRegReg;

      lhsReg = cg->evaluate(firstChild);
      midReg = cg->evaluate(secondChild);
      rhsReg = cg->evaluate(thirdChild);

      generateRegRegInstruction(fpMovRegRegOpcode, node, result, lhsReg, cg);
      generateRegRegRegInstruction(opcode, node, result, midReg, rhsReg, cg);
      }

   if (memLoadLhs)
      {
      cg->recursivelyDecReferenceCount(firstChild);
      }
   else
      {
      cg->decReferenceCount(firstChild);
      }

   if (memLoadMiddle)
      {
      cg->recursivelyDecReferenceCount(secondChild);
      }
   else
      {
      cg->decReferenceCount(secondChild);
      }

   if (memLoadRhs)
      {
      cg->recursivelyDecReferenceCount(thirdChild);
      }
   else
      {
      cg->decReferenceCount(thirdChild);
      }

   node->setRegister(result);

   return result;
   }

// Convert serial String.hashCode computation into vectorization copy and implement with SSE instruction
//
// Conversion process example:
//
//    str[8] = example string representing 8 characters (compressed or decompressed)
//
//    The serial method for creating the hash:
//          hash = 0, offset = 0, count = 8
//          for (int i = offset; i < offset+count; ++i) {
//                hash = (hash << 5) - hash + str[i];
//          }
//
//    Note that ((hash << 5) - hash) is equivalent to hash * 31
//
//    Expanding out the for loop:
//          hash = ((((((((0*31+str[0])*31+str[1])*31+str[2])*31+str[3])*31+str[4])*31+str[5])*31+str[6])*31+str[7])
//
//    Simplified:
//          hash =        (31^7)*str[0] + (31^6)*str[1] + (31^5)*str[2] + (31^4)*str[3]
//                      + (31^3)*str[4] + (31^2)*str[5] + (31^1)*str[6] + (31^0)*str[7]
//
//    Rearranged:
//          hash =        (31^7)*str[0] + (31^3)*str[4]
//                      + (31^6)*str[1] + (31^2)*str[5]
//                      + (31^5)*str[2] + (31^1)*str[6]
//                      + (31^4)*str[3] + (31^0)*str[7]
//
//    Factor out [31^3, 31^2, 31^1, 31^0]:
//          hash =        31^3*((31^4)*str[0] + str[4])           Vector[0]
//                      + 31^2*((31^4)*str[1] + str[5])           Vector[1]
//                      + 31^1*((31^4)*str[2] + str[6])           Vector[2]
//                      + 31^0*((31^4)*str[3] + str[7])           Vector[3]
//
//    Keep factoring out any 31^4 if possible (this example has no such case). If the string was 12 characters long then:
//          31^3*((31^8)*str[0] + (31^4)*str[4] + (31^0)*str[8]) would become 31^3*(31^4((31^4)*str[0] + str[4]) + (31^0)*str[8])
//
//    Vectorization is done by simultaneously calculating the four sums that hash is made of (each -> is a successive step):
//          Vector[0] = str[0] -> multiply 31^4 -> add str[4] -> multiply 31^3
//          Vector[1] = str[1] -> multiply 31^4 -> add str[5] -> multiply 31^2
//          Vector[2] = str[2] -> multiply 31^4 -> add str[6] -> multiply 31^1
//          Vector[3] = str[3] -> multiply 31^4 -> add str[7] -> multiply 1
//
//    Adding these four vectorized values together produces the required hash.
//    If the number of characters in the string is not a multiple of 4, then the remainder of the hash is calculated serially.
//
// Implementation overview:
//
// start_label
// if size < threshold, goto serial_label, current threshold is 4
//    xmm0 = load 16 bytes align constant [923521, 923521, 923521, 923521]
//    xmm1 = 0
// SSEloop
//    xmm2 = decompressed: load 8 byte value in lower 8 bytes.
//           compressed: load 4 byte value in lower 4 bytes
//    xmm1 = xmm1 * xmm0
//    if(isCompressed)
//          movzxbd xmm2, xmm2
//    else
//          movzxwd xmm2, xmm2
//    xmm1 = xmm1 + xmm2
//    i = i + 4;
//    cmp i, end -3
//    jge SSEloop
// xmm0 = load 16 bytes align [31^3, 31^2, 31, 1]
// xmm1 = xmm1 * xmm0      value contains [a0, a1, a2, a3]
// xmm0 = xmm1
// xmm0 = xmm0 >> 64 bits
// xmm1 = xmm1 + xmm0       reduce add [a0+a2, a1+a3, .., ...]
// xmm0 = xmm1
// xmm0 = xmm0 >> 32 bits
// xmm1 = xmm1 + xmm0       reduce add [a0+a2 + a1+a3, .., .., ..]
// movd xmm1, GPR1
//
// serial_label
//
// cmp i end
// jle end
// serial_loop
// GPR2 = GPR1
// GPR1 = GPR1 << 5
// GPR1 = GPR1 - GPR2
// GPR2 = load c[i]
// add GPR1, GPR2
// dec i
// cmp i, end
// jl serial_loop
//
// end_label
static TR::Register* inlineStringHashCode(TR::Node* node, bool isCompressed, TR::CodeGenerator* cg)
   {
   TR_ASSERT(node->getChild(1)->getOpCodeValue() == TR::iconst && node->getChild(1)->getInt() == 0, "String hashcode offset can only be const zero.");

   const int size = 4;
   auto shift = isCompressed ? 0 : 1;

   auto address = cg->evaluate(node->getChild(0));
   auto length = cg->evaluate(node->getChild(2));
   auto index = cg->allocateRegister();
   auto hash = cg->allocateRegister();
   auto tmp = cg->allocateRegister();
   auto hashXMM = cg->allocateRegister(TR_VRF);
   auto tmpXMM = cg->allocateRegister(TR_VRF);
   auto multiplierXMM = cg->allocateRegister(TR_VRF);

   auto begLabel = generateLabelSymbol(cg);
   auto endLabel = generateLabelSymbol(cg);
   auto loopLabel = generateLabelSymbol(cg);
   begLabel->setStartInternalControlFlow();
   endLabel->setEndInternalControlFlow();
   auto deps = generateRegisterDependencyConditions((uint8_t)6, (uint8_t)6, cg);
   deps->addPreCondition(address, TR::RealRegister::NoReg, cg);
   deps->addPreCondition(index, TR::RealRegister::NoReg, cg);
   deps->addPreCondition(length, TR::RealRegister::NoReg, cg);
   deps->addPreCondition(multiplierXMM, TR::RealRegister::NoReg, cg);
   deps->addPreCondition(tmpXMM, TR::RealRegister::NoReg, cg);
   deps->addPreCondition(hashXMM, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(address, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(index, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(length, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(multiplierXMM, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(tmpXMM, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(hashXMM, TR::RealRegister::NoReg, cg);

   generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, index, length, cg);
   generateRegImmInstruction(TR::InstOpCode::AND4RegImms, node, index, size-1, cg); // mod size
   generateRegMemInstruction(TR::InstOpCode::CMOVE4RegMem, node, index, generateX86MemoryReference(cg->findOrCreate4ByteConstant(node, size), cg), cg);

   // Prepend zeros
   {
   TR::Compilation *comp = cg->comp();

   static uint64_t MASKDECOMPRESSED[] = { 0x0000000000000000ULL, 0xffffffffffffffffULL };
   static uint64_t MASKCOMPRESSED[]   = { 0xffffffff00000000ULL, 0x0000000000000000ULL };
   generateRegMemInstruction(isCompressed ? TR::InstOpCode::MOVDRegMem : TR::InstOpCode::MOVQRegMem, node, hashXMM, generateX86MemoryReference(address, index, shift, -(size << shift) + TR::Compiler->om.contiguousArrayHeaderSizeInBytes(), cg), cg);
   generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, tmp, generateX86MemoryReference(cg->findOrCreate16ByteConstant(node, isCompressed ? MASKCOMPRESSED : MASKDECOMPRESSED), cg), cg);

   auto mr = generateX86MemoryReference(tmp, index, shift, 0, cg);
   if (comp->target().cpu.supportsAVX())
      {
      generateRegMemInstruction(TR::InstOpCode::PANDRegMem, node, hashXMM, mr, cg);
      }
   else
      {
      generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, tmpXMM, mr, cg);
      generateRegRegInstruction(TR::InstOpCode::PANDRegReg, node, hashXMM, tmpXMM, cg);
      }
   generateRegRegInstruction(isCompressed ? TR::InstOpCode::PMOVZXBDRegReg : TR::InstOpCode::PMOVZXWDRegReg, node, hashXMM, hashXMM, cg);
   }

   // Reduction Loop
   {
   static uint32_t multiplier[] = { 31*31*31*31, 31*31*31*31, 31*31*31*31, 31*31*31*31 };
   generateLabelInstruction(TR::InstOpCode::label, node, begLabel, cg);
   generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, index, length, cg);
   generateLabelInstruction(TR::InstOpCode::JGE4, node, endLabel, cg);
   generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, multiplierXMM, generateX86MemoryReference(cg->findOrCreate16ByteConstant(node, multiplier), cg), cg);
   generateLabelInstruction(TR::InstOpCode::label, node, loopLabel, cg);
   generateRegRegInstruction(TR::InstOpCode::PMULLDRegReg, node, hashXMM, multiplierXMM, cg);
   generateRegMemInstruction(isCompressed ? TR::InstOpCode::PMOVZXBDRegMem : TR::InstOpCode::PMOVZXWDRegMem, node, tmpXMM, generateX86MemoryReference(address, index, shift, TR::Compiler->om.contiguousArrayHeaderSizeInBytes(), cg), cg);
   generateRegImmInstruction(TR::InstOpCode::ADD4RegImms, node, index, 4, cg);
   generateRegRegInstruction(TR::InstOpCode::PADDDRegReg, node, hashXMM, tmpXMM, cg);
   generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, index, length, cg);
   generateLabelInstruction(TR::InstOpCode::JL4, node, loopLabel, cg);
   generateLabelInstruction(TR::InstOpCode::label, node, endLabel, deps, cg);
   }

   // Finalization
   {
   static uint32_t multiplier[] = { 31*31*31, 31*31, 31, 1 };
   generateRegMemInstruction(TR::InstOpCode::PMULLDRegMem, node, hashXMM, generateX86MemoryReference(cg->findOrCreate16ByteConstant(node, multiplier), cg), cg);
   generateRegRegImmInstruction(TR::InstOpCode::PSHUFDRegRegImm1, node, tmpXMM, hashXMM, 0x0e, cg);
   generateRegRegInstruction(TR::InstOpCode::PADDDRegReg, node, hashXMM, tmpXMM, cg);
   generateRegRegImmInstruction(TR::InstOpCode::PSHUFDRegRegImm1, node, tmpXMM, hashXMM, 0x01, cg);
   generateRegRegInstruction(TR::InstOpCode::PADDDRegReg, node, hashXMM, tmpXMM, cg);
   }

   generateRegRegInstruction(TR::InstOpCode::MOVDReg4Reg, node, hash, hashXMM, cg);

   cg->stopUsingRegister(index);
   cg->stopUsingRegister(tmp);
   cg->stopUsingRegister(hashXMM);
   cg->stopUsingRegister(tmpXMM);
   cg->stopUsingRegister(multiplierXMM);

   node->setRegister(hash);
   cg->decReferenceCount(node->getChild(0));
   cg->recursivelyDecReferenceCount(node->getChild(1));
   cg->decReferenceCount(node->getChild(2));
   return hash;
   }

TR::Register* J9::X86::TreeEvaluator::inlineVectorizedHashCode(TR::Node* node, TR::CodeGenerator* cg)
   {
   TR::Node *initialValueNode = node->getChild(3);
   TR::Node *elementTypeNode = node->getChild(4);
   TR::Register* registerHash = NULL;

   switch (elementTypeNode->getConstValue())
      {
      case 4:  // T_BOOLEAN
         registerHash = vectorizedHashCodeHelper(node, TR::Int8, initialValueNode, false, cg);
         break;
      case 8:  // T_BYTE
         registerHash = vectorizedHashCodeHelper(node, TR::Int8, initialValueNode, true, cg);
         break;
      case 5:  // T_CHAR
         registerHash = vectorizedHashCodeHelper(node, TR::Int16, initialValueNode, false, cg);
         break;
      case 9:  // T_SHORT
         registerHash = vectorizedHashCodeHelper(node, TR::Int16, initialValueNode, true, cg);
         break;
      case 10: // T_INT
         registerHash = vectorizedHashCodeHelper(node, TR::Int32, initialValueNode, true, cg);
         break;
      default:
         return NULL;
      }

   if (registerHash != NULL)
      cg->decReferenceCount(elementTypeNode);

   node->setRegister(registerHash);

   return registerHash;
   }

TR::Register *
J9::X86::TreeEvaluator::vectorizedHashCodeReductionHelper(TR::Node* node, TR::Register **vectorRegisters, int32_t numVectors, TR::Register *tmpVectorRegVRF, TR::Register *result, TR::VectorLength vl, TR::DataType dt, TR::CodeGenerator* cg)
   {
   TR::InstOpCode opcode = TR::InstOpCode::PADDDRegReg;
   TR::Register *vectorRegVRF = vectorRegisters[0];

   // If we unrolled the main loop, vertically add the vectors together first
   // then proceed to do horizontal reduction
   for (int32_t i = 1; i < numVectors; i++)
      {
      OMR::X86::Encoding opcodeEncoding = opcode.getSIMDEncoding(&cg->comp()->target().cpu, vl);
      generateRegRegInstruction(TR::InstOpCode::PADDDRegReg, node, vectorRegVRF, vectorRegisters[i], cg, opcodeEncoding);
      }

   // Reduce lanes -> horizontally add all vector elements together
   // Store the result in a GPR

   switch (vl)
      {
      case TR::VectorLength512:
         // extract 256-bits from zmm and store in ymm, then perform vertical operation
         generateRegRegImmInstruction(TR::InstOpCode::VEXTRACTF64X4YmmZmmImm1, node, tmpVectorRegVRF, vectorRegVRF, 0xFF, cg);
         generateRegRegInstruction(opcode.getMnemonic(), node, vectorRegVRF, tmpVectorRegVRF, cg, opcode.getSIMDEncoding(&cg->comp()->target().cpu, TR::VectorLength256));
         // Fallthrough to treat remaining result as 256-bit vector
      case TR::VectorLength256:
          // extract 128 bits from ymm and store in xmm, then perform vertical operation
         generateRegRegImmInstruction(TR::InstOpCode::VEXTRACTF128RegRegImm1, node, tmpVectorRegVRF, vectorRegVRF, 0xFF, cg);
         generateRegRegInstruction(opcode.getMnemonic(), node, vectorRegVRF, tmpVectorRegVRF, cg, opcode.getSIMDEncoding(&cg->comp()->target().cpu, TR::VectorLength128));
         // Fallthrough to treat remaining result as 128-bit vector
      case TR::VectorLength128:
         generateRegRegImmInstruction(TR::InstOpCode::PSHUFDRegRegImm1, node, tmpVectorRegVRF, vectorRegVRF, 0x0e, cg);
         generateRegRegInstruction(TR::InstOpCode::PADDDRegReg, node, vectorRegVRF, tmpVectorRegVRF, cg);
         generateRegRegImmInstruction(TR::InstOpCode::PSHUFDRegRegImm1, node, tmpVectorRegVRF, vectorRegVRF, 0x01, cg);
         generateRegRegInstruction(TR::InstOpCode::PADDDRegReg, node, vectorRegVRF, tmpVectorRegVRF, cg);
         break;
      default:
         TR_ASSERT_FATAL(false, "Unsupported vector length");
      }

   generateRegRegInstruction(TR::InstOpCode::MOVDReg4Reg, node, result, vectorRegVRF, cg);
   return result;
   }

// 31^64, 31^63, ..., 31^0
static const int32_t powersOf31[65] = {
      1304393729,
      2120287199, -208698303, -1807847521, -1166696319, 100911967, 280349889, -1930619105, 630458625,
      20337375, 693392705, 438009503, -1925533311, 769170015, 1133190593, -240540129, -7759359,
      969581023, 1970939457, -1183347297, -1700740479, -1024693921, -448696639, 124073247, -1935660287,
      1461579999, -922683583, 1632803999, 329765761, 1950300255, 1725480897, 1025491999, 2111290369,
      -2010103841, 350799937, 11316127, 693101697, -254736545, 961614017, 31019807, -2077209343,
      -67006753, 1244764481, -2038056289, 211350913, -408824225, -844471871, -997072353, 1353309697,
      -510534177, 1507551809, -505558625, -293403007, 129082719, -1796951359, -196513505, -1807454463,
      1742810335, 887503681, 28629151, 923521, 29791, 961, 31, 1
};

//
// This function generates the main vectorized loop in the vectorizedHashCode(...) implementation. It supports both
// signed and unsigned integer elements up to 32-bits in size, vector lengths from 128-bit up to 512-bit and up to 4x
// loop unrolling.
//
// This helper generates code in three sections,
//   1. Setup registers, load multiplier constants
//     a. Initialize vector constants used in step 2.
//     b. Zero out running hash vectors. The number of running hash vectors is equal to the unrolling factor.
//     c. If an initial hash is non-zero, move that value into the first element of the first running hash vector.
//   2. Generate main loop with x unrolling
//     a. Load batch of data using size appropriate vector load, with zero extension for unsigned types, sign extension
//        for signed types.
//     b. Multiply batch by (31^(n-1), 31^(n-2), ..., 31^0), where n is the number of elements being processed in the loop
//       i. In case of a loop unroll x times, the multiplier is split into x vectors. The first batch of elements is
//          multiplied by the higher powers of 31. The next batch of elements are multiplied by the next multiplier
//          vector, and so on.
//     c. Multiply the existing running hash the vector (31^n, 31^n, ..., 31^n)
//     d. Add product from 2 (b) to the running hash.
//   3. Combine and reduces vectors into a single result
//     a. If the main loop is unrolled, add the running hash vectors together.
//     b. Horizontally add the elements together and move the result to a generate-purpose register.
//
TR::Register *
J9::X86::TreeEvaluator::vectorizedHashCodeLoopHelper(TR::Node *node,
                                                     TR::DataType dt,
                                                     TR::VectorLength vl,
                                                     bool isSigned,
                                                     TR::Register *result,
                                                     TR::Register *initialHash,
                                                     TR::Register *index,
                                                     TR::Register *length,
                                                     TR::Register *arrayAddress,
                                                     int32_t unrollCount,
                                                     TR::CodeGenerator *cg)
   {
   static OMR::X86::Encoding vectorEncodingMethods[3] = { OMR::X86::Default, OMR::X86::VEX_L256, OMR::X86::EVEX_L512 };
   static int32_t vectorSizes[3] = { 4, 8, 16 };
   int32_t shift = dt - TR::Int8; /* i8 -> 0, i16 -> 1, i32 -> 2 */

   TR_ASSERT_FATAL(shift >= 0 && shift <= 2, "Unsupported datatype for vectorized hashcode");
   TR_ASSERT_FATAL(unrollCount == 1 || unrollCount == 2 || unrollCount == 4, "Unroll count must be 1/2/4");
   TR_ASSERT_FATAL(vl >= TR::VectorLength128 && vl <= TR::VectorLength512, "Unsupported vector length");

   OMR::X86::Encoding vectorEncoding = vectorEncodingMethods[vl - TR::VectorLength128];
   int32_t vectorSizeElements = vectorSizes[vl - TR::VectorLength128];
   int32_t numElements = vectorSizeElements * unrollCount;

   TR::RegisterDependencyConditions *deps = generateRegisterDependencyConditions((uint8_t)0, (uint8_t)11, cg);
   TR::Register *tmp = cg->allocateRegister(TR_GPR);
   TR::Register *tmpVRF = cg->allocateRegister(TR_VRF);
   TR::Register *multiplierVRF = cg->allocateRegister(TR_VRF);

   TR::Register *hashRegsVRF[4];
   TR::Register *multiplier31PowNRegsVRF[4];

   deps->addPostCondition(tmp, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(tmpVRF, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(multiplierVRF, TR::RealRegister::NoReg, cg);

   for (int32_t i = 0; i < unrollCount; i++)
      {
      hashRegsVRF[i] = cg->allocateRegister(TR_VRF);
      multiplier31PowNRegsVRF[i] = cg->allocateRegister(TR_VRF);

      deps->addPostCondition(hashRegsVRF[i], TR::RealRegister::NoReg, cg);
      deps->addPostCondition(multiplier31PowNRegsVRF[i], TR::RealRegister::NoReg, cg);
      }

   deps->stopAddingConditions();

   TR::LabelSymbol *begLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *endLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *loopLabel = generateLabelSymbol(cg);

   begLabel->setStartInternalControlFlow();
   endLabel->setEndInternalControlFlow();

   generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, result, initialHash, cg);
   generateLabelInstruction(TR::InstOpCode::label, node, begLabel, cg);
   generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, tmp, length, cg);
   generateRegImmInstruction(TR::InstOpCode::AND4RegImm4, node, tmp, ~(numElements - 1), cg);

   {
   generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, index, tmp, cg);
   generateLabelInstruction(TR::InstOpCode::JGE4, node, endLabel, cg);

   // Initialize Constants outside of loop body but after the first compare
   for (int32_t i = 0; i < unrollCount; i++)
      generateRegRegInstruction(TR::InstOpCode::PXORRegReg, node, hashRegsVRF[i], hashRegsVRF[i], cg, vectorEncoding);

   generateRegRegInstruction(TR::InstOpCode::MOVDRegReg4, node, hashRegsVRF[0], initialHash, cg);

   int32_t multiplier31PowNData[16];
   // Fill multiplier array with 31^numElements
   std::fill_n(multiplier31PowNData, 16, powersOf31[64 - numElements]);
   generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, multiplierVRF, generateX86MemoryReference(cg->findOrCreateConstantDataSnippet(node, multiplier31PowNData, vectorSizeElements * sizeof(int32_t)), cg), cg, vectorEncoding);

   for (int32_t i = 0; i < unrollCount; i++)
      {
      // Based on the unrolling factor (x), we need to split multiplier constant (powers of 31) into x vectors.
      //   The constant is as follows (31^(n-1), 31^(n-2), ..., 31^0)
      // Where n is the number of elements processed in the loop. n is directly proportional to the unrolling factor (x)
      //
      // For example, given an unrolling factor (x) of 4, and a vector length of 128-bits, we will process up to 16
      // elements per iteration of the main loop. This means the multiplication vectors are as follows:
      //
      //   multiplier31PowNRegsVRF[0] = (31^15, 31^14, 31^13, 31^12),
      //   multiplier31PowNRegsVRF[1] = (31^11, 31^10, 31^9, 31^8),
      //   multiplier31PowNRegsVRF[2] = (31^7, 31^6, 31^5, 31^4),
      //   multiplier31PowNRegsVRF[3] = (31^3, 31^2, 31^1, 31^0),
      //
      TR::Register *multiplier31PowN_i = multiplier31PowNRegsVRF[i];
      const int32_t vectorSize = vectorSizeElements * 4;
      int32_t offset = sizeof(powersOf31) / sizeof(int32_t) - (vectorSizeElements * (unrollCount - i));

      int32_t *multiplier = const_cast<int32_t *>(powersOf31 + offset);
      TR::MemoryReference *mr = generateX86MemoryReference(cg->findOrCreateConstantDataSnippet(node, multiplier, vectorSize), cg);

      generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, multiplier31PowN_i, mr, cg, vectorEncoding);
      }
   }

   generateLabelInstruction(TR::InstOpCode::label, node, loopLabel, cg);

   {
   // Main loop body;

   for (int32_t i = 0; i < unrollCount; i++)
      {
      // Load in the next batch of elements. (sign/zero) extend i8, i16 to i32
      TR::InstOpCode::Mnemonic loadOpcode = TR::InstOpCode::bad;
      int32_t elementSize;

      switch (dt)
         {
         case TR::Int8:
            loadOpcode = isSigned ? TR::InstOpCode::PMOVSXBDRegMem  : TR::InstOpCode::PMOVZXBDRegMem;
            elementSize = 1;
            break;
         case TR::Int16:
            loadOpcode = isSigned ? TR::InstOpCode::PMOVSXWDRegMem : TR::InstOpCode::PMOVZXWDRegMem;
            elementSize = 2;
            break;
         case TR::Int32:
            loadOpcode = TR::InstOpCode::MOVDQURegMem;
            elementSize = 4;
            break;
         default:
            TR_ASSERT_FATAL(false, "Unsupported element type");
            break;
         }

      int32_t displacement = TR::Compiler->om.contiguousArrayHeaderSizeInBytes() + i * (vectorSizeElements * elementSize);
      TR::MemoryReference *mr = generateX86MemoryReference(arrayAddress, index, shift, displacement, cg);
      // load next batch of data
      generateRegMemInstruction(loadOpcode, node, tmpVRF, mr, cg, vectorEncoding);

      // tmpVRF = tmpVRF * multiplierVRF
      generateRegRegInstruction(TR::InstOpCode::PMULLDRegReg, node, tmpVRF, multiplier31PowNRegsVRF[i], cg, vectorEncoding);
      // hashRegsVRF = ( hashRegsVRF * {31^vl, ..., 31^vl} ) + tmpVRF
      generateRegRegInstruction(TR::InstOpCode::PMULLDRegReg, node, hashRegsVRF[i], multiplierVRF, cg, vectorEncoding);
      generateRegRegInstruction(TR::InstOpCode::PADDDRegReg, node, hashRegsVRF[i], tmpVRF, cg, vectorEncoding);
      }
   }

   // Increase loop index by the number of processed elements
   generateRegImmInstruction(TR::InstOpCode::ADD4RegImms, node, index, numElements, cg);
   // Compare index with numElements and loop back if necessary
   generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, index, tmp, cg);
   generateLabelInstruction(TR::InstOpCode::JL4, node, loopLabel, cg);

   vectorizedHashCodeReductionHelper(node, hashRegsVRF, unrollCount, tmpVRF, result, vl, dt, cg);
   generateLabelInstruction(TR::InstOpCode::label, node, endLabel, deps, cg);

   cg->stopUsingRegister(tmp);
   cg->stopUsingRegister(tmpVRF);
   cg->stopUsingRegister(multiplierVRF);

   for (int32_t i = 0; i < unrollCount; i++) cg->stopUsingRegister(multiplier31PowNRegsVRF[i]);
   for (int32_t i = 0; i < unrollCount; i++) cg->stopUsingRegister(hashRegsVRF[i]);

   return result;
   }

/**
 * @brief Implements the vectorized `hashCode` computation using SIMD instructions.
 *
 * This implementation supports various processor microarchitectures (sse4.1+), enabling vectorization
 * with 128-bit, 256-bit, and 512-bit vectors. It handles both signed and unsigned integer element types
 * of 8-bit, 16-bit, and 32-bit sizes. Elements are processed iteratively as 32-bit integers, with
 * smaller types being sign- or zero-extended to 32-bit integers.
 *
 * The following steps are performed to generate the vectorized `hashCode` implementation:
 *
 * 1. Generate the main vectorized loop unrolled by a factor of x (default is 4) at the highest
 *    available vector length.
 * 2. Generate a secondary vectorized loop, not unrolled, using 128-bit vectors.
 *    - This secondary loop is necessary because small amounts of data or residual data
 *      may not fit into the unrolled main loop, which often requires large amounts of
 *      data to process efficiently. By using a simpler 128-bit vectorized loop, better
 *      performance can be achieved for these cases.
 * 3. Process any remaining elements sequentially:
 *    @code
 *    for (; index < length; index++) { hash = 31 * hash + arr[index]; }
 *    @endcode
 *
 * The implementation relies on two helper functions:
 * - `vectorizedHashCodeLoopHelper(...)`:
 *   Generates the vectorized loop code for the specified type and vector size.
 * - `vectorizedHashCodeReductionHelper(...)`:
 *   Generates code to reduce x vectors by summing all elements together into a scalar hashCode value.
 *
 * @note Future enhancements could investigate optimal unrolling factors based on:
 * - Block hotness
 * - Array length
 * - Cache implications of unrolling
 *
 * Given the large expected size of the generated code with unrolling, this intrinsic could
 * exert significant pressure on the code cache. This effect may be especially pronounced if
 * the vectorized hashCode algorithm is inlined multiple times in the same method.
 *
 * @param node      The input node to process.
 * @param dt        The data type of the elements.
 * @param nodeHash  The node representing the initial hash value.
 * @param isSigned  Indicates whether the elements are signed.
 * @param cg        The code generator instance.
 * @return The register containing the computed hashCode value.
 */
TR::Register *
J9::X86::TreeEvaluator::vectorizedHashCodeHelper(TR::Node *node, TR::DataType dt, TR::Node *nodeHash, bool isSigned,
                                                 TR::CodeGenerator *cg)
   {
   int32_t shift = dt - TR::Int8; /* i8 -> 0, i16 -> 1, i32 -> 2 */

   TR_ASSERT_FATAL(shift >= 0 && shift <= 2, "Unsupported datatype for vectorized hashcode");

   TR::Compilation *comp = cg->comp();
   TR::VectorLength vl = cg->getMaxPreferredVectorLength();
   TR::Node *addressNode = node->getChild(0);

   bool nonZeroOffset = node->getChild(1)->getOpCodeValue() != TR::iconst || node->getChild(1)->getInt() != 0;
   bool addressIs64bits = TR::TreeEvaluator::getNodeIs64Bit(addressNode, cg);

   TR::Register *address = nonZeroOffset ? TR::TreeEvaluator::intOrLongClobberEvaluate(addressNode, addressIs64bits, cg) : cg->evaluate(addressNode);
   TR::Register *length = cg->evaluate(node->getChild(2));
   TR::Register *initHash = nodeHash ? cg->intClobberEvaluate(nodeHash) : cg->allocateRegister(TR_GPR);
   TR::Register *index = cg->allocateRegister();
   TR::Register *result = cg->allocateRegister();
   TR::Register *tmp = cg->allocateRegister();

   TR::RegisterDependencyConditions *deps = generateRegisterDependencyConditions(0, 6, cg);

   deps->addPostCondition(result, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(address, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(index, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(tmp, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(initHash, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(length, TR::RealRegister::NoReg, cg);
   deps->stopAddingConditions();

   if (nonZeroOffset)
      {
      TR::Register *offset = cg->evaluate(node->getChild(1));
      TR::MemoryReference *memRef = generateX86MemoryReference(address, offset, shift, 0, cg);
      generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, address, memRef, cg);
      }

   if (!nodeHash)
      {
      // If nodeHash is not provided, assume initial hash value of 0.
      generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, initHash, initHash, cg);
      }

   // Set index ptr to 0
   generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, index, index, cg);

   // Generate Main Loop; 4x Unrolled seems to yield the best performance for large arrays
   static char *unrollVar = feGetEnv("TR_setInlineVectorHashCodeUnrollCount");

#ifdef TR_TARGET_64BIT
   int32_t unrollCount = unrollVar ? atoi(unrollVar) : 4;
#else
   int32_t unrollCount = 1;
#endif

   vectorizedHashCodeLoopHelper(node, dt, vl, isSigned, result, initHash, index, length, address, unrollCount, cg);

   static bool disableSecondLoop = feGetEnv("TR_disableVectorHashCodeSecondLoop") != NULL;

   // Generate a second vectorized loop if not disabled and Vl/unrollCount are not the same as the first loop
   if (!disableSecondLoop && (unrollCount != 1 || vl != TR::VectorLength128))
      {
      generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, initHash, result, cg);
      vectorizedHashCodeLoopHelper(node, dt, TR::VectorLength128, isSigned, result, initHash, index, length, address, 1, cg);
      }

   // handle residual elements sequentially
   // for (; index < length; index++) { hash = 31 * hash + arr[index]; }
   {
   TR::LabelSymbol *residueBeginLoopLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *residueEndLoopLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *residueLoopLabel = generateLabelSymbol(cg);

   residueBeginLoopLabel->setStartInternalControlFlow();
   residueEndLoopLabel->setEndInternalControlFlow();

   generateLabelInstruction(TR::InstOpCode::label, node, residueBeginLoopLabel, cg);
   generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, index, length, cg);
   generateLabelInstruction(TR::InstOpCode::JGE4, node, residueEndLoopLabel, cg);
   generateLabelInstruction(TR::InstOpCode::label, node, residueLoopLabel, cg);

   // hash = 31 * hash + arr[index] = tmp * hash + arr[index]
   generateRegRegImmInstruction(TR::InstOpCode::IMUL4RegRegImm4, node, result, result, 31, cg);

   static TR::InstOpCode::Mnemonic signedLoadOpcode[3]   = { TR::InstOpCode::MOVSXReg4Mem1, TR::InstOpCode::MOVSXReg4Mem2, TR::InstOpCode::L4RegMem };
   static TR::InstOpCode::Mnemonic unsignedLoadOpcode[3] = { TR::InstOpCode::MOVZXReg4Mem1, TR::InstOpCode::MOVZXReg4Mem2, TR::InstOpCode::L4RegMem };
   TR::InstOpCode::Mnemonic loadOpcode = isSigned ? signedLoadOpcode[dt - TR::Int8] : unsignedLoadOpcode[dt - TR::Int8];

   generateRegMemInstruction(loadOpcode, node, tmp, generateX86MemoryReference(address, index, shift, TR::Compiler->om.contiguousArrayHeaderSizeInBytes(), cg), cg);
   generateRegRegInstruction(TR::InstOpCode::ADDRegReg(), node, result, tmp, cg);

   // Increase loop index by the number of processed elements
   generateRegInstruction(TR::InstOpCode::INCReg(), node, index, cg);

   // Compare index with numElements and loop back if necessary
   generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, index, length, cg);
   generateLabelInstruction(TR::InstOpCode::JL4, node, residueLoopLabel, cg);
   generateLabelInstruction(TR::InstOpCode::label, node, residueEndLoopLabel, deps, cg);
   }

   if (nonZeroOffset)
      {
      cg->stopUsingRegister(address);
      }

   cg->stopUsingRegister(initHash);
   cg->stopUsingRegister(index);
   cg->stopUsingRegister(tmp);

   cg->decReferenceCount(node->getChild(0));
   cg->decReferenceCount(node->getChild(1));
   cg->decReferenceCount(node->getChild(2));

   if (nodeHash)
      cg->decReferenceCount(nodeHash);

   return result;
   }

static bool
getNodeIs64Bit(
      TR::Node *node,
      TR::CodeGenerator *cg)
   {
   /* This function is intended to allow existing 32-bit instruction selection code
    * to be reused, almost unchanged, to do the corresponding 64-bit logic on AMD64.
    * It compiles away to nothing on IA32, thus preserving performance and code size
    * on IA32, while allowing the logic to be generalized to suit AMD64.
    *
    * Don't use this function for 64-bit logic on IA32; instead, either (1) use
    * separate logic, or (2) use a different test for 64-bitness.  Usually this is
    * not a hindrance, because 64-bit code on IA32 uses register pairs and other
    * things that are totally different from their 32-bit counterparts.
    */

   TR_ASSERT(cg->comp()->target().is64Bit() || node->getSize() <= 4, "64-bit nodes on 32-bit platforms shouldn't use getNodeIs64Bit");
   return cg->comp()->target().is64Bit() && node->getSize() > 4;
   }

static
TR::Register *intOrLongClobberEvaluate(
      TR::Node *node,
      bool nodeIs64Bit,
      TR::CodeGenerator *cg)
   {
   if (nodeIs64Bit)
      {
      TR_ASSERT(getNodeIs64Bit(node, cg), "nodeIs64Bit must be consistent with node size");
      return cg->longClobberEvaluate(node);
      }
   else
      {
      TR_ASSERT(!getNodeIs64Bit(node, cg), "nodeIs64Bit must be consistent with node size");
      return cg->intClobberEvaluate(node);
      }
   }

/**
 * \brief
 *   Generate inlined instructions equivalent to com/ibm/jit/JITHelpers.intrinsicIndexOfLatin1 or com/ibm/jit/JITHelpers.intrinsicIndexOfUTF16
 *
 * \param node
 *   The tree node
 *
 * \param cg
 *   The Code Generator
 *
 * \param isLatin1
 *   True when the string is Latin1, False when the string is UTF16
 *
 * Note that this version does not support discontiguous arrays
 */
static TR::Register* inlineIntrinsicIndexOf(TR::Node* node, TR::CodeGenerator* cg, bool isLatin1)
   {
   static uint8_t MASKOFSIZEONE[] =
      {
      0x00, 0x00, 0x00, 0x00,
      0x00, 0x00, 0x00, 0x00,
      0x00, 0x00, 0x00, 0x00,
      0x00, 0x00, 0x00, 0x00,
      };
   static uint8_t MASKOFSIZETWO[] =
      {
      0x00, 0x01, 0x00, 0x01,
      0x00, 0x01, 0x00, 0x01,
      0x00, 0x01, 0x00, 0x01,
      0x00, 0x01, 0x00, 0x01,
      };

   uint8_t width = 16;
   uint8_t shift = 0;
   uint8_t* shuffleMask = NULL;
   auto compareOp = TR::InstOpCode::bad;
   if(isLatin1)
      {
      shuffleMask = MASKOFSIZEONE;
      compareOp = TR::InstOpCode::PCMPEQBRegReg;
      shift = 0;
      }
   else
      {
      shuffleMask = MASKOFSIZETWO;
      compareOp = TR::InstOpCode::PCMPEQWRegReg;
      shift = 1;
      }

   // This evaluator function handles different indexOf() intrinsics, some of which are static calls without a
   // receiver. Hence, the need for static call check.
   const bool isStaticCall = node->getSymbolReference()->getSymbol()->castToMethodSymbol()->isStatic();
   const uint8_t firstCallArgIdx = isStaticCall ? 0 : 1;
   auto array = cg->evaluate(node->getChild(firstCallArgIdx));
   auto ch = cg->evaluate(node->getChild(firstCallArgIdx+1));
   auto offset = cg->evaluate(node->getChild(firstCallArgIdx+2));
   auto length = cg->evaluate(node->getChild(firstCallArgIdx+3));

   auto ECX = cg->allocateRegister();
   auto result = cg->allocateRegister();
   auto scratch = cg->allocateRegister();
   auto scratchXMM = cg->allocateRegister(TR_VRF);
   auto valueXMM = cg->allocateRegister(TR_VRF);

   auto dependencies = generateRegisterDependencyConditions((uint8_t)7, (uint8_t)7, cg);
   dependencies->addPreCondition(ECX, TR::RealRegister::ecx, cg);
   dependencies->addPreCondition(array, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(length, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(result, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(scratch, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(scratchXMM, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(valueXMM, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(ECX, TR::RealRegister::ecx, cg);
   dependencies->addPostCondition(array, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(length, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(result, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(scratch, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(scratchXMM, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(valueXMM, TR::RealRegister::NoReg, cg);

   auto begLabel = generateLabelSymbol(cg);
   auto endLabel = generateLabelSymbol(cg);
   auto loopLabel = generateLabelSymbol(cg);
   begLabel->setStartInternalControlFlow();
   endLabel->setEndInternalControlFlow();

   generateRegRegInstruction(TR::InstOpCode::MOVDRegReg4, node, valueXMM, ch, cg);
   generateRegMemInstruction(TR::InstOpCode::PSHUFBRegMem, node, valueXMM, generateX86MemoryReference(cg->findOrCreate16ByteConstant(node, shuffleMask), cg), cg);

   generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, result, offset, cg);

   generateLabelInstruction(TR::InstOpCode::label, node, begLabel, cg);
   generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, scratch, generateX86MemoryReference(array, result, shift, TR::Compiler->om.contiguousArrayHeaderSizeInBytes(), cg), cg);
   generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, ECX, scratch, cg);
   generateRegImmInstruction(TR::InstOpCode::ANDRegImms(), node, scratch, ~(width - 1), cg);
   generateRegImmInstruction(TR::InstOpCode::ANDRegImms(), node, ECX, width - 1, cg);
   generateLabelInstruction(TR::InstOpCode::JE1, node, loopLabel, cg);

   generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, scratchXMM, generateX86MemoryReference(scratch, 0, cg), cg);
   generateRegRegInstruction(compareOp, node, scratchXMM, valueXMM, cg);
   generateRegRegInstruction(TR::InstOpCode::PMOVMSKB4RegReg, node, scratch, scratchXMM, cg);
   generateRegInstruction(TR::InstOpCode::SHR4RegCL, node, scratch, cg);
   generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, scratch, scratch, cg);
   generateLabelInstruction(TR::InstOpCode::JNE1, node, endLabel, cg);
   if (shift)
      {
      generateRegImmInstruction(TR::InstOpCode::SHR4RegImm1, node, ECX, shift, cg);
      }
   generateRegImmInstruction(TR::InstOpCode::ADD4RegImms, node, result, width >> shift, cg);
   generateRegRegInstruction(TR::InstOpCode::SUB4RegReg, node, result, ECX, cg);
   generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, result, length, cg);
   generateLabelInstruction(TR::InstOpCode::JGE1, node, endLabel, cg);

   generateLabelInstruction(TR::InstOpCode::label, node, loopLabel, cg);
   generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, scratchXMM, generateX86MemoryReference(array, result, shift, TR::Compiler->om.contiguousArrayHeaderSizeInBytes(), cg), cg);
   generateRegRegInstruction(compareOp, node, scratchXMM, valueXMM, cg);
   generateRegRegInstruction(TR::InstOpCode::PMOVMSKB4RegReg, node, scratch, scratchXMM, cg);
   generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, scratch, scratch, cg);
   generateLabelInstruction(TR::InstOpCode::JNE1, node, endLabel, cg);
   generateRegImmInstruction(TR::InstOpCode::ADD4RegImms, node, result, width >> shift, cg);
   generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, result, length, cg);
   generateLabelInstruction(TR::InstOpCode::JL1, node, loopLabel, cg);
   generateLabelInstruction(TR::InstOpCode::label, node, endLabel, dependencies, cg);

   generateRegRegInstruction(TR::InstOpCode::BSF4RegReg, node, scratch, scratch, cg);
   if (shift)
      {
      generateRegImmInstruction(TR::InstOpCode::SHR4RegImm1, node, scratch, shift, cg);
      }
   generateRegRegInstruction(TR::InstOpCode::ADDRegReg(), node, result, scratch, cg);
   generateRegRegInstruction(TR::InstOpCode::CMPRegReg(), node, result, length, cg);
   generateRegMemInstruction(TR::InstOpCode::CMOVGERegMem(), node, result, generateX86MemoryReference(cg->comp()->target().is32Bit() ? cg->findOrCreate4ByteConstant(node, -1) : cg->findOrCreate8ByteConstant(node, -1), cg), cg);

   cg->stopUsingRegister(ECX);
   cg->stopUsingRegister(scratch);
   cg->stopUsingRegister(scratchXMM);
   cg->stopUsingRegister(valueXMM);


   node->setRegister(result);
   if (!isStaticCall)
      {
      cg->recursivelyDecReferenceCount(node->getChild(0));
      }
   for (int32_t i = firstCallArgIdx; i < node->getNumChildren(); i++)
      {
      cg->decReferenceCount(node->getChild(i));
      }
   return result;
   }

/**
 * \brief
 *   Generate inlined instructions equivalent to java/lang/StringLatin1.indexOf([BI[BII)I or java/lang/StringUTF16.indexOf([BI[BII)I
 *
 * \param node
 *   The tree node
 *
 * \param cg
 *   The Code Generator
 *
 * \param isLatin1
 *   True when the string is Latin1, False when the string is UTF16
 *
 * Note that this version does not support discontiguous arrays
 */
static TR::Register* inlineIntrinsicStringIndexOfString(TR::Node* node, TR::CodeGenerator* cg, bool isLatin1)
   {
   static bool disableStrIdxOfStr = (feGetEnv("TR_disableStrIdxOfStr") != NULL);
   if (disableStrIdxOfStr) return NULL;

   static bool verboseStrIdxOfStr = (feGetEnv("TR_verboseStrIdxOfStr") != NULL);
   if (verboseStrIdxOfStr)
      {
      fprintf(stderr, "*%s.indexOfString: %s @%s\n", isLatin1 ? "Latin1" : "UTF16", cg->comp()->signature(), cg->comp()->getHotnessName());
      }

   TR_ASSERT_FATAL(cg->comp()->target().is64Bit(), "Not supported on 32-bit platform");

   // This evaluator function handles different indexOf() intrinsics, some of which are static calls without a
   // receiver. Hence, the need for static call check.
   const bool isStaticCall = node->getSymbolReference()->getSymbol()->castToMethodSymbol()->isStatic();
   const uint8_t firstCallArgIdx = isStaticCall ? 0 : 1;
   TR::Register *s1Reg = cg->evaluate(node->getChild(firstCallArgIdx));
   TR::Node *s1lenNode = node->getChild(firstCallArgIdx+1);
   TR::Register *s1lenReg = cg->evaluate(s1lenNode);
   TR::Register *s2Reg = cg->evaluate(node->getChild(firstCallArgIdx+2));
   TR::Register *s2lenReg = cg->evaluate(node->getChild(firstCallArgIdx+3));
   TR::Node *offsetNode = node->getChild(firstCallArgIdx+4);
   TR::Register *offsetReg = cg->evaluate(offsetNode);

   TR::Register *maxReg;
   if (s1lenNode->getReferenceCount() == 1)
      {
      maxReg = s1lenReg;
      }
   else
      {
      maxReg = cg->allocateRegister(TR_GPR);
      generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, maxReg, s1lenReg, cg);
      }

   TR::Register *resultReg;
   if (offsetNode->getReferenceCount() == 1)
      {
      resultReg = offsetReg;
      }
   else
      {
      resultReg = cg->allocateRegister(TR_GPR);
      generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, resultReg, offsetReg, cg);
      }

   static uint8_t MASKOFSIZEONE[] =
      {
      0x00, 0x00, 0x00, 0x00,
      0x00, 0x00, 0x00, 0x00,
      0x00, 0x00, 0x00, 0x00,
      0x00, 0x00, 0x00, 0x00,
      };
   static uint8_t MASKOFSIZETWO[] =
      {
      0x00, 0x01, 0x00, 0x01,
      0x00, 0x01, 0x00, 0x01,
      0x00, 0x01, 0x00, 0x01,
      0x00, 0x01, 0x00, 0x01,
      };

   const uint8_t width = 16;
   uint8_t shift = 0;
   uint8_t *shuffleMask = NULL;
   TR::InstOpCode::Mnemonic compareOp = TR::InstOpCode::bad;
   if (isLatin1)
      {
      shuffleMask = MASKOFSIZEONE;
      compareOp = TR::InstOpCode::PCMPEQBRegReg;
      shift = 0;
      }
   else
      {
      shuffleMask = MASKOFSIZETWO;
      compareOp = TR::InstOpCode::PCMPEQWRegReg;
      shift = 1;
      }

   TR::Register *ECX = cg->allocateRegister(TR_GPR);
   TR::Register *tmpReg = cg->allocateRegister(TR_GPR);
   TR::Register *xmmReg1 = cg->allocateRegister(TR_VRF);
   TR::Register *xmmReg2 = cg->allocateRegister(TR_VRF);
   TR::Register *xmmReg3 = cg->allocateRegister(TR_VRF);
   TR::Register *s1addrReg = cg->allocateRegister(TR_GPR);
   TR::Register *s2idxReg = cg->allocateRegister(TR_GPR);

   TR::RegisterDependencyConditions *dependencies = generateRegisterDependencyConditions((uint8_t)12, (uint8_t)12, cg);
   dependencies->addPreCondition(s1Reg, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(s2Reg, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(s2lenReg, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(maxReg, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(resultReg, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(ECX, TR::RealRegister::ecx, cg);
   dependencies->addPreCondition(tmpReg, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(xmmReg1, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(xmmReg2, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(xmmReg3, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(s1addrReg, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(s2idxReg, TR::RealRegister::NoReg, cg);

   dependencies->addPostCondition(s1Reg, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(s2Reg, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(s2lenReg, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(maxReg, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(resultReg, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(ECX, TR::RealRegister::ecx, cg);
   dependencies->addPostCondition(tmpReg, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(xmmReg1, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(xmmReg2, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(xmmReg3, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(s1addrReg, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(s2idxReg, TR::RealRegister::NoReg, cg);

   TR::LabelSymbol *startLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *outerLoopLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *firstCharLoopLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *firstCharMatchedLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *qwordLoopLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *byteLoopLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *unmatchedLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *notFoundLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *foundLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *doneLabel = generateLabelSymbol(cg);

   startLabel->setStartInternalControlFlow();
   doneLabel->setEndInternalControlFlow();

   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

   int32_t hdrSize = static_cast<int32_t>(TR::Compiler->om.contiguousArrayHeaderSizeInBytes());

   // load first char of s2
   generateRegMemInstruction(isLatin1 ? TR::InstOpCode::MOVZXReg4Mem1 : TR::InstOpCode::MOVZXReg4Mem2, node, tmpReg, generateX86MemoryReference(s2Reg, hdrSize, cg), cg);
   generateRegRegInstruction(TR::InstOpCode::MOVDRegReg4, node, xmmReg2, tmpReg, cg);
   generateRegMemInstruction(TR::InstOpCode::PSHUFBRegMem, node, xmmReg2, generateX86MemoryReference(cg->findOrCreate16ByteConstant(node, shuffleMask), cg), cg);

   // calculate max
   generateRegRegInstruction(TR::InstOpCode::SUB4RegReg, node, maxReg, s2lenReg, cg); // s1len - s2len

   // outer loop
   generateLabelInstruction(TR::InstOpCode::label, node, outerLoopLabel, cg);
   generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, resultReg, maxReg, cg);
   generateLabelInstruction(TR::InstOpCode::JG4, node, notFoundLabel, cg);

   generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, tmpReg, generateX86MemoryReference(s1Reg, resultReg, shift, hdrSize, cg), cg);
   generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, ECX, tmpReg, cg);
   generateRegImmInstruction(TR::InstOpCode::AND4RegImms, node, ECX, width - 1, cg);
   generateLabelInstruction(TR::InstOpCode::JE1, node, firstCharLoopLabel, cg);

   generateRegImmInstruction(TR::InstOpCode::ANDRegImms(), node, tmpReg, ~(width - 1), cg);
   generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, xmmReg1, generateX86MemoryReference(tmpReg, 0, cg), cg);
   generateRegRegInstruction(compareOp, node, xmmReg1, xmmReg2, cg);
   generateRegRegInstruction(TR::InstOpCode::PMOVMSKB4RegReg, node, tmpReg, xmmReg1, cg);
   generateRegInstruction(TR::InstOpCode::SHR4RegCL, node, tmpReg, cg);
   generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, tmpReg, tmpReg, cg);
   generateLabelInstruction(TR::InstOpCode::JNE1, node, firstCharMatchedLabel, cg);
   if (!isLatin1)
      {
      generateRegImmInstruction(TR::InstOpCode::SHR4RegImm1, node, ECX, 1, cg);
      }
   generateRegImmInstruction(TR::InstOpCode::ADD4RegImms, node, resultReg, width >> shift, cg);
   generateRegRegInstruction(TR::InstOpCode::SUB4RegReg, node, resultReg, ECX, cg);
   generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, resultReg, maxReg, cg);
   generateLabelInstruction(TR::InstOpCode::JG4, node, notFoundLabel, cg);

   // loop for finding the first char
   generateLabelInstruction(TR::InstOpCode::label, node, firstCharLoopLabel, cg);
   generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, xmmReg1, generateX86MemoryReference(s1Reg, resultReg, shift, hdrSize, cg), cg);
   generateRegRegInstruction(compareOp, node, xmmReg1, xmmReg2, cg);
   generateRegRegInstruction(TR::InstOpCode::PMOVMSKB4RegReg, node, tmpReg, xmmReg1, cg);
   generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, tmpReg, tmpReg, cg);
   generateLabelInstruction(TR::InstOpCode::JNE1, node, firstCharMatchedLabel, cg);
   generateRegImmInstruction(TR::InstOpCode::ADD4RegImms, node, resultReg, width >> shift, cg);
   generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, resultReg, maxReg, cg);
   generateLabelInstruction(TR::InstOpCode::JLE1, node, firstCharLoopLabel, cg);
   generateLabelInstruction(TR::InstOpCode::JMP4, node, notFoundLabel, cg);

   // first char matched
   generateLabelInstruction(TR::InstOpCode::label, node, firstCharMatchedLabel, cg);

   generateRegRegInstruction(TR::InstOpCode::BSF4RegReg, node, tmpReg, tmpReg, cg);
   if (!isLatin1)
      {
      generateRegImmInstruction(TR::InstOpCode::SHR4RegImm1, node, tmpReg, 1, cg);
      }
   generateRegRegInstruction(TR::InstOpCode::ADD4RegReg, node, resultReg, tmpReg, cg);

   generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, resultReg, maxReg, cg);
   generateLabelInstruction(TR::InstOpCode::JG4, node, notFoundLabel, cg);

   generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, s1addrReg, generateX86MemoryReference(s1Reg, resultReg, shift, hdrSize, cg), cg); // s1addr = &(s1[resultReg << shift])
   generateRegImmInstruction(TR::InstOpCode::MOV4RegImm4, node, s2idxReg, 1, cg); // s2idx = 1

   generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, ECX, generateX86MemoryReference(s2lenReg, -1, cg), cg); // ECX = s2len - 1: 1st char has already matched
   generateRegImmInstruction(TR::InstOpCode::SHR4RegImm1, node, ECX, 4 - shift, cg); // div by 16 or 8
   generateLabelInstruction(TR::InstOpCode::JE1, node, byteLoopLabel, cg);

   // Compare by 16 bytes
   generateLabelInstruction(TR::InstOpCode::label, node, qwordLoopLabel, cg);
   generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, xmmReg1, generateX86MemoryReference(s1addrReg, s2idxReg, shift, 0, cg), cg);
   generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, xmmReg3, generateX86MemoryReference(s2Reg, s2idxReg, shift, hdrSize, cg), cg);
   generateRegRegInstruction(TR::InstOpCode::PCMPEQBRegReg, node, xmmReg1, xmmReg3, cg);
   generateRegRegInstruction(TR::InstOpCode::PMOVMSKB4RegReg, node, tmpReg, xmmReg1, cg);
   generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, tmpReg, 0xffff, cg);
   generateLabelInstruction(TR::InstOpCode::JNE1, node, unmatchedLabel, cg);

   generateRegImmInstruction(TR::InstOpCode::ADD4RegImms, node, s2idxReg, width >> shift, cg);
   generateRegImmInstruction(TR::InstOpCode::SUB4RegImms, node, ECX, 1, cg);
   generateLabelInstruction(TR::InstOpCode::JG1, node, qwordLoopLabel, cg);

   // Compare each byte
   generateLabelInstruction(TR::InstOpCode::label, node, byteLoopLabel, cg);
   generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, s2lenReg, s2idxReg, cg);
   generateLabelInstruction(TR::InstOpCode::JLE1, node, doneLabel, cg); // resultReg has the result

   generateRegMemInstruction(isLatin1 ? TR::InstOpCode::L1RegMem : TR::InstOpCode::L2RegMem, node, tmpReg, generateX86MemoryReference(s2Reg, s2idxReg, shift, hdrSize, cg), cg);
   generateMemRegInstruction(isLatin1 ? TR::InstOpCode::CMP1MemReg : TR::InstOpCode::CMP2MemReg, node, generateX86MemoryReference(s1addrReg, s2idxReg, shift, 0, cg), tmpReg, cg);
   generateLabelInstruction(TR::InstOpCode::JNE1, node, unmatchedLabel, cg);

   generateRegImmInstruction(TR::InstOpCode::ADD4RegImms, node, s2idxReg, 1, cg);
   generateLabelInstruction(TR::InstOpCode::JMP1, node, byteLoopLabel, cg);

   // substring did not match
   generateLabelInstruction(TR::InstOpCode::label, node, unmatchedLabel, cg);
   generateRegImmInstruction(TR::InstOpCode::ADD4RegImms, node, resultReg, 1, cg);
   generateLabelInstruction(TR::InstOpCode::JMP4, node, outerLoopLabel, cg);

   // not found
   generateLabelInstruction(TR::InstOpCode::label, node, notFoundLabel, cg);
   generateRegImmInstruction(TR::InstOpCode::OR4RegImms, node, resultReg, -1, cg);
   // fall through to doneLabel

   generateLabelInstruction(TR::InstOpCode::label, node, doneLabel, dependencies, cg);

   cg->stopUsingRegister(ECX);
   cg->stopUsingRegister(tmpReg);
   cg->stopUsingRegister(xmmReg1);
   cg->stopUsingRegister(xmmReg2);
   cg->stopUsingRegister(xmmReg3);
   cg->stopUsingRegister(s1addrReg);
   cg->stopUsingRegister(s2idxReg);

   if (maxReg != s1lenReg)
      {
      cg->stopUsingRegister(maxReg);
      }

   node->setRegister(resultReg);

   if (!isStaticCall)
      {
      cg->recursivelyDecReferenceCount(node->getChild(0));
      }
   for (int32_t i = firstCallArgIdx; i < node->getNumChildren(); i++)
      {
      cg->decReferenceCount(node->getChild(i));
      }

   return resultReg;
   }

/**
 * \brief
 *   Generate inlined instructions equivalent to sun/misc/Unsafe.compareAndSwapObject or jdk/internal/misc/Unsafe.compareAndSwapObject
 *
 * \param node
 *   The tree node
 *
 * \param cg
 *   The Code Generator
 *
 */
static TR::Register* inlineCompareAndSwapObjectNative(TR::Node* node, TR::CodeGenerator* cg, bool isExchange)
   {
   TR::Compilation *comp = cg->comp();

   TR_ASSERT(!TR::Compiler->om.canGenerateArraylets() || node->isUnsafeGetPutCASCallOnNonArray(), "This evaluator does not support arraylets.");

   cg->recursivelyDecReferenceCount(node->getChild(0)); // The Unsafe
   TR::Node* objectNode   = node->getChild(1);
   TR::Node* offsetNode   = node->getChild(2);
   TR::Node* oldValueNode = node->getChild(3);
   TR::Node* newValueNode = node->getChild(4);

   TR::Register* object   = cg->evaluate(objectNode);
   TR::Register* offset   = cg->evaluate(offsetNode);
   TR::Register* oldValue = cg->evaluate(oldValueNode);
   TR::Register* newValue = cg->evaluate(newValueNode);
   TR::Register* result   = isExchange ? NULL : cg->allocateRegister();
   TR::Register* EAX      = cg->allocateRegister();
   TR::Register* tmp      = cg->allocateRegister();

   bool use64BitClasses = comp->target().is64Bit() && !comp->useCompressedPointers();

   if (comp->target().is32Bit())
      {
      // Assume that the offset is positive and not pathologically large (i.e., > 2^31).
      offset = offset->getLowOrder();
      }

#if defined(OMR_GC_CONCURRENT_SCAVENGER)
   switch (TR::Compiler->om.readBarrierType())
      {
      case gc_modron_readbar_none:
         break;
      case gc_modron_readbar_always:
         generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, tmp, generateX86MemoryReference(object, offset, 0, cg), cg);
         generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, floatTemp1), cg), tmp, cg);
         generateHelperCallInstruction(node, TR_softwareReadBarrier, NULL, cg);
         break;
      case gc_modron_readbar_range_check:
         {
         generateRegMemInstruction(TR::InstOpCode::LRegMem(use64BitClasses), node, tmp, generateX86MemoryReference(object, offset, 0, cg), cg);

         TR::LabelSymbol* begLabel = generateLabelSymbol(cg);
         TR::LabelSymbol* endLabel = generateLabelSymbol(cg);
         TR::LabelSymbol* rdbarLabel = generateLabelSymbol(cg);
         begLabel->setStartInternalControlFlow();
         endLabel->setEndInternalControlFlow();

         TR::RegisterDependencyConditions* deps = generateRegisterDependencyConditions((uint8_t)1, 1, cg);
         deps->addPreCondition(tmp, TR::RealRegister::NoReg, cg);
         deps->addPostCondition(tmp, TR::RealRegister::NoReg, cg);

         generateLabelInstruction(TR::InstOpCode::label, node, begLabel, cg);

         generateRegMemInstruction(TR::InstOpCode::CMPRegMem(use64BitClasses), node, tmp, generateX86MemoryReference(cg->getVMThreadRegister(), comp->fej9()->thisThreadGetEvacuateBaseAddressOffset(), cg), cg);
         generateLabelInstruction(TR::InstOpCode::JAE4, node, rdbarLabel, cg);

         {
         TR_OutlinedInstructionsGenerator og(rdbarLabel, node, cg);
         generateRegMemInstruction(TR::InstOpCode::CMPRegMem(use64BitClasses), node, tmp, generateX86MemoryReference(cg->getVMThreadRegister(), comp->fej9()->thisThreadGetEvacuateTopAddressOffset(), cg), cg);
         generateLabelInstruction(TR::InstOpCode::JA4, node, endLabel, cg);
         generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, tmp, generateX86MemoryReference(object, offset, 0, cg), cg);
         generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, floatTemp1), cg), tmp, cg);
         generateHelperCallInstruction(node, TR_softwareReadBarrier, NULL, cg);
         generateLabelInstruction(TR::InstOpCode::JMP4, node, endLabel, cg);

         og.endOutlinedInstructionSequence();
         }

         generateLabelInstruction(TR::InstOpCode::label, node, endLabel, deps, cg);
         }
         break;
      default:
         TR_ASSERT(false, "Unsupported Read Barrier Type.");
         break;
      }
#endif

   generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, EAX, oldValue, cg);
   generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, tmp, newValue, cg);
   if (TR::Compiler->om.compressedReferenceShiftOffset() != 0)
      {
      if (!oldValueNode->isNull())
         {
         generateRegImmInstruction(TR::InstOpCode::SHRRegImm1(), node, EAX, TR::Compiler->om.compressedReferenceShiftOffset(), cg);
         }
      if (!newValueNode->isNull())
         {
         generateRegImmInstruction(TR::InstOpCode::SHRRegImm1(), node, tmp, TR::Compiler->om.compressedReferenceShiftOffset(), cg);
         }
      }

   TR::RegisterDependencyConditions* deps = generateRegisterDependencyConditions((uint8_t)1, 1, cg);
   deps->addPreCondition(EAX, TR::RealRegister::eax, cg);
   deps->addPostCondition(EAX, TR::RealRegister::eax, cg);
   generateMemRegInstruction(use64BitClasses ? TR::InstOpCode::LCMPXCHG8MemReg : TR::InstOpCode::LCMPXCHG4MemReg, node, generateX86MemoryReference(object, offset, 0, cg), tmp, deps, cg);

   if (isExchange)
      {
      result = EAX;
      result->setContainsCollectedReference();
      if (TR::Compiler->om.compressedReferenceShiftOffset() != 0)
         {
         generateRegImmInstruction(TR::InstOpCode::SHLRegImm1(), node, EAX, TR::Compiler->om.compressedReferenceShiftOffset(), cg);
         }
      }
   else
      {
      generateRegInstruction(TR::InstOpCode::SETE1Reg, node, result, cg);
      generateRegRegInstruction(TR::InstOpCode::MOVZXReg4Reg1, node, result, result, cg);
      }

   // Non-realtime: Generate a write barrier for this kind of object.
   //
   if (!comp->getOptions()->realTimeGC())
      {
      // We could insert a runtime test for whether the write actually succeeded or not.
      // However, since in practice it will almost always succeed we do not want to
      // penalize general runtime performance especially if it is still correct to do
      // a write barrier even if the store never actually happened.
      TR_X86ScratchRegisterManager *scratchRegisterManager = cg->generateScratchRegisterManager();

      TR::TreeEvaluator::VMwrtbarWithoutStoreEvaluator(
         node,
         objectNode,
         newValueNode,
         NULL,
         scratchRegisterManager,
         cg);
      }

   cg->stopUsingRegister(tmp);
   if (!isExchange)
      {
      cg->stopUsingRegister(EAX);
      }
   node->setRegister(result);
   for (int32_t i = 1; i < node->getNumChildren(); i++)
      {
      cg->decReferenceCount(node->getChild(i));
      }
   return result;
   }

/** Replaces a call to an Unsafe CAS method with inline instructions.
   @return true if the call was replaced, false if it was not.

   Note that this function must have behaviour consistent with the function
   willNotInlineCompareAndSwapNative in openj9/runtime/compiler/x/codegen/J9CodeGenerator.cpp
*/
static bool
inlineCompareAndSwapNative(
      TR::Node *node,
      int8_t size,
      bool isObject,
      bool isExchange,
      TR::CodeGenerator *cg)
   {
   TR::Node *firstChild    = node->getFirstChild();
   TR::Node *objectChild   = node->getSecondChild();
   TR::Node *offsetChild   = node->getChild(2);
   TR::Node *oldValueChild = node->getChild(3);
   TR::Node *newValueChild = node->getChild(4);
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(comp->fe());

   TR::InstOpCode::Mnemonic op;

   if (TR::Compiler->om.canGenerateArraylets() && !node->isUnsafeGetPutCASCallOnNonArray())
      return false;

   // size = 4 --> CMPXCHG4
   // size = 8 --> if 64-bit -> CMPXCHG8
   //              else if proc supports CMPXCHG8B -> CMPXCHG8B
   //              else return false
   //
   // Do this early so we can return early without additional evaluations.
   //
   switch (size)
      {
      case 4:
         op = TR::InstOpCode::LCMPXCHG4MemReg;
         break;
      case 8:
         if (comp->target().is64Bit())
            {
            op = TR::InstOpCode::LCMPXCHG8MemReg;
            }
         else if (comp->target().cpu.supportsFeature(OMR_FEATURE_X86_CX8))
            {
            op = TR::InstOpCode::LCMPXCHG8BMem;
            }
         else
            {
            return false;
            }
         break;
      default:
         TR_ASSERT_FATAL_WITH_NODE(node, false, "Unknown dataSize: %d\n", size);
         return false;
      }

   // In Java9 the sun.misc.Unsafe JNI methods have been moved to jdk.internal,
   // with a set of wrappers remaining in sun.misc to delegate to the new package.
   // We can be called in this function for the wrappers (which we will
   // not be converting to assembly), the new jdk.internal JNI methods or the
   // Java8 sun.misc JNI methods (both of which we will convert). We can
   // differentiate between these cases by testing with isNative() on the method.
   {
      TR::MethodSymbol *methodSymbol = node->getSymbol()->getMethodSymbol();
      if (methodSymbol && !methodSymbol->isNative())
         return false;
   }

   cg->recursivelyDecReferenceCount(firstChild);

   TR::Register *objectReg = cg->evaluate(objectChild);

   TR::Register *offsetReg = NULL;
   int32_t      offset    = 0;

   if (offsetChild->getOpCode().isLoadConst() && !offsetChild->getRegister() && IS_32BIT_SIGNED(offsetChild->getLongInt()))
      {
      offset = (int32_t)(offsetChild->getLongInt());
      }
   else
      {
      offsetReg = cg->evaluate(offsetChild);

      // Assume that the offset is positive and not pathologically large (i.e., > 2^31).
      //
      if (comp->target().is32Bit())
         offsetReg = offsetReg->getLowOrder();
      }

   TR::MemoryReference *mr;

   if (offsetReg)
      mr = generateX86MemoryReference(objectReg, offsetReg, 0, cg);
   else
      mr = generateX86MemoryReference(objectReg, offset, cg);

   bool bumpedRefCount = false;
   TR::Node *translatedNode = newValueChild;
   if (comp->useCompressedPointers() &&
       isObject &&
       (newValueChild->getDataType() != TR::Address))
      {
      bool useShiftedOffsets = (TR::Compiler->om.compressedReferenceShiftOffset() != 0);

      translatedNode = newValueChild;
      if (translatedNode->getOpCode().isConversion())
         translatedNode = translatedNode->getFirstChild();
      if (translatedNode->getOpCode().isRightShift()) // optional
         translatedNode = translatedNode->getFirstChild();

      translatedNode = newValueChild;
      if (useShiftedOffsets)
         {
         while ((translatedNode->getNumChildren() > 0) &&
                 (translatedNode->getOpCodeValue() != TR::a2l))
            translatedNode = translatedNode->getFirstChild();

         if (translatedNode->getOpCodeValue() == TR::a2l)
            translatedNode = translatedNode->getFirstChild();

         // this is required so that different registers are
         // allocated for the actual store and translated values
         bumpedRefCount = true;
         translatedNode->incReferenceCount();
         }
      }

   TR::Register *newValueRegister = cg->evaluate(newValueChild);

   TR::Register *oldValueRegister;
   switch (size)
      {
      case 4:
         oldValueRegister = cg->intClobberEvaluate(oldValueChild);
         break;
      case 8:
         oldValueRegister = cg->longClobberEvaluate(oldValueChild);
         break;
      default:
         TR_ASSERT_FATAL_WITH_NODE(node, false, "Unknown dataSize: %d\n", size);
         break;
      }
   bool killOldValueRegister = (oldValueChild->getReferenceCount() > 1) ? true : false;

   TR::RegisterDependencyConditions  *deps;
   TR_X86ScratchRegisterManager *scratchRegisterManagerForRealTime = NULL;
   TR::Register *storeAddressRegForRealTime = NULL;

   if (comp->getOptions()->realTimeGC() && isObject)
      {
      scratchRegisterManagerForRealTime = cg->generateScratchRegisterManager();

      // If reference is unresolved, need to resolve it right here before the barrier starts
      // Otherwise, we could get stopped during the resolution and that could invalidate any tests we would have performend
      //   beforehand
      // For simplicity, just evaluate the store address into storeAddressRegForRealTime right now
      storeAddressRegForRealTime = scratchRegisterManagerForRealTime->findOrCreateScratchRegister();
      generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, storeAddressRegForRealTime, mr, cg);
      if (node->getSymbolReference()->isUnresolved())
         {
         TR::TreeEvaluator::padUnresolvedDataReferences(node, *node->getSymbolReference(), cg);

         // storeMR was created against a (i)wrtbar node which is a store.  The unresolved data snippet that
         //  was created set the checkVolatility bit based on that node being a store.  Since the resolution
         //  is now going to occur on a LEA instruction, which does not require any memory fence and hence
         //  no volatility check, we need to clear that "store" ness of the unresolved data snippet
         TR::UnresolvedDataSnippet *snippet = mr->getUnresolvedDataSnippet();
         if (snippet)
            snippet->resetUnresolvedStore();
         }

      TR::TreeEvaluator::VMwrtbarRealTimeWithoutStoreEvaluator(
         node,
         mr,
         storeAddressRegForRealTime,
         objectChild,
         translatedNode,
         NULL,
         scratchRegisterManagerForRealTime,
         cg);
      }

   TR::MemoryReference *cmpxchgMR = mr;

   TR::Register *resultReg;
   if (op == TR::InstOpCode::LCMPXCHG8BMem)
      {
      int numDeps = 4;
      if (storeAddressRegForRealTime != NULL)
         {
         numDeps++;
         cmpxchgMR = generateX86MemoryReference(storeAddressRegForRealTime, 0, cg);
         }

      if (scratchRegisterManagerForRealTime)
         numDeps += scratchRegisterManagerForRealTime->numAvailableRegisters();

      deps = generateRegisterDependencyConditions(numDeps, numDeps, cg);
      deps->addPreCondition(oldValueRegister->getLowOrder(), TR::RealRegister::eax, cg);
      deps->addPreCondition(oldValueRegister->getHighOrder(), TR::RealRegister::edx, cg);
      deps->addPreCondition(newValueRegister->getLowOrder(), TR::RealRegister::ebx, cg);
      deps->addPreCondition(newValueRegister->getHighOrder(), TR::RealRegister::ecx, cg);
      deps->addPostCondition(oldValueRegister->getLowOrder(), TR::RealRegister::eax, cg);
      deps->addPostCondition(oldValueRegister->getHighOrder(), TR::RealRegister::edx, cg);
      deps->addPostCondition(newValueRegister->getLowOrder(), TR::RealRegister::ebx, cg);
      deps->addPostCondition(newValueRegister->getHighOrder(), TR::RealRegister::ecx, cg);

      if (scratchRegisterManagerForRealTime)
         scratchRegisterManagerForRealTime->addScratchRegistersToDependencyList(deps);

      deps->stopAddingConditions();

      generateMemInstruction(op, node, cmpxchgMR, deps, cg);
      }
   else
      {
      int numDeps = 1;
      if (storeAddressRegForRealTime != NULL)
         {
         numDeps++;
         cmpxchgMR = generateX86MemoryReference(storeAddressRegForRealTime, 0, cg);
         }

      if (scratchRegisterManagerForRealTime)
         numDeps += scratchRegisterManagerForRealTime->numAvailableRegisters();

      deps = generateRegisterDependencyConditions(numDeps, numDeps, cg);
      deps->addPreCondition(oldValueRegister, TR::RealRegister::eax, cg);
      deps->addPostCondition(oldValueRegister, TR::RealRegister::eax, cg);

      if (scratchRegisterManagerForRealTime)
         scratchRegisterManagerForRealTime->addScratchRegistersToDependencyList(deps);

      deps->stopAddingConditions();

      generateMemRegInstruction(op, node, cmpxchgMR, newValueRegister, deps, cg);
      }

   if (isExchange)
      {
      killOldValueRegister = false;
      resultReg = oldValueRegister;
      if (isObject)
         {
         resultReg->setContainsCollectedReference();
         if (TR::Compiler->om.compressedReferenceShiftOffset() != 0)
            {
            generateRegImmInstruction(TR::InstOpCode::SHLRegImm1(), node, resultReg, TR::Compiler->om.compressedReferenceShiftOffset(), cg);
            }
         }
      }

   if (killOldValueRegister)
      cg->stopUsingRegister(oldValueRegister);

   if (storeAddressRegForRealTime)
      scratchRegisterManagerForRealTime->reclaimScratchRegister(storeAddressRegForRealTime);

   if (!isExchange)
      {
      resultReg = cg->allocateRegister();
      generateRegInstruction(TR::InstOpCode::SETE1Reg, node, resultReg, cg);
      generateRegRegInstruction(TR::InstOpCode::MOVZXReg4Reg1, node, resultReg, resultReg, cg);
      }

   // Non-realtime: Generate a write barrier for this kind of object.
   //
   if (!comp->getOptions()->realTimeGC() && isObject)
      {
      // We could insert a runtime test for whether the write actually succeeded or not.
      // However, since in practice it will almost always succeed we do not want to
      // penalize general runtime performance especially if it is still correct to do
      // a write barrier even if the store never actually happened.
      //
      // A branch
      //
      TR_X86ScratchRegisterManager *scratchRegisterManager = cg->generateScratchRegisterManager();

      TR::TreeEvaluator::VMwrtbarWithoutStoreEvaluator(
         node,
         objectChild,
         translatedNode,
         NULL,
         scratchRegisterManager,
         cg);
      }

   node->setRegister(resultReg);

   cg->decReferenceCount(objectChild);
   if (offsetReg)
      {
      cg->decReferenceCount(offsetChild);
      }
   else
      {
      cg->recursivelyDecReferenceCount(offsetChild);
      }
   cg->decReferenceCount(oldValueChild);
   cg->decReferenceCount(newValueChild);
   if (bumpedRefCount)
      cg->decReferenceCount(translatedNode);

   return true;
   }


/**
 * \brief
 *   Generate inlined instructions equivalent to java/lang/StringCoding.hasNegatives or java/lang/StringCoding.countPositives
 *
 * \param node
 *   The tree node
 *
 * \param recognizedMethod
 *   The method being inlined, should be either hasNegatives or countPositives
 *
 * \param cg
 *   The Code Generator
 */
static TR::Register* inlineHasNegativesOrCountPositives(TR::Node* node, TR::RecognizedMethod recognizedMethod, TR::CodeGenerator* cg)
   {
   // Arguments to hasNegatives or countPositives
   // Byte array
   TR::Register *bufReg = cg->longClobberEvaluate(node->getChild(0));
   // Offset (i.e. index to begin counting from)
   TR::Register *offsetReg = cg->evaluate(node->getChild(1));
   // Length of byte array
   TR::Register *lengthReg = cg->evaluate(node->getChild(2));

   // Store a boolean indicating whether we are generating code for hasNegatives or countPositives
   bool isHasNegatives = recognizedMethod == TR::java_lang_StringCoding_hasNegatives;

   // The offset of the start of array data
   int32_t offsetToDataElements = TR::Compiler->om.contiguousArrayHeaderSizeInBytes();

   // A key part of the main loop of this algorithm is the pmovmskb instruction,
   // which extracts the sign bits from a source register and collects them into a destination register
   // We need to specify the encoding of this instruction so that the code generator knows we want the 16 byte version
   TR::InstOpCode pmovmskb = TR::InstOpCode::PMOVMSKB4RegReg;
   OMR::X86::Encoding pmovmskbEncoding = pmovmskb.getSIMDEncoding(&cg->comp()->target().cpu, TR::VectorLength128);
   static bool disableSIMDHasNegativesCountPositives = feGetEnv("TR_disableSIMDHasNegativesCountPositives") != NULL;
   bool useVectorInstructions = (pmovmskbEncoding != OMR::X86::Encoding::Bad) && !disableSIMDHasNegativesCountPositives;

   TR::Register *loopLimitReg = cg->allocateRegister();
   TR::Register *limitReg = cg->allocateRegister();
   TR::Register *maskReg = cg->allocateRegister();
   TR::Register *indexReg = cg->allocateRegister();
   TR::Register *chunkReg = cg->allocateRegister();
   TR::Register *xmmChunkReg = NULL;
   if (useVectorInstructions)
      {
      xmmChunkReg = cg->allocateRegister(TR_VRF);
      }

   uint8_t numDependencies = useVectorInstructions ? 9 : 8;
   TR::RegisterDependencyConditions *dependencies = generateRegisterDependencyConditions(numDependencies, numDependencies, cg);
   dependencies->addPreCondition(bufReg, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(offsetReg, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(lengthReg, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(loopLimitReg, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(limitReg, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(maskReg, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(indexReg, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(chunkReg, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(bufReg, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(offsetReg, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(lengthReg, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(loopLimitReg, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(limitReg, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(maskReg, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(indexReg, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(chunkReg, TR::RealRegister::NoReg, cg);
   if (useVectorInstructions)
      {
      dependencies->addPreCondition(xmmChunkReg, TR::RealRegister::NoReg, cg);
      dependencies->addPostCondition(xmmChunkReg, TR::RealRegister::NoReg, cg);
      }
   dependencies->stopAddingConditions();

   // Labels
   TR::LabelSymbol *begLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *endLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *loopLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *residualLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *threeOrMoreBytesLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *fiveOrMoreBytesLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *nineOrMoreBytesLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *residualTestLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *returnNoNegativesLabel = NULL;
   TR::LabelSymbol *returnHasNegativesLabel = NULL;
   TR::LabelSymbol *returnBooleanLabel = NULL;
   if (isHasNegatives)
      {
      returnBooleanLabel = generateLabelSymbol(cg);
      }
   else
      {
      returnNoNegativesLabel = generateLabelSymbol(cg);
      returnHasNegativesLabel = generateLabelSymbol(cg);
      }
   begLabel->setStartInternalControlFlow();
   endLabel->setEndInternalControlFlow();


   generateLabelInstruction(TR::InstOpCode::label, node, begLabel, cg);

   // If offheap is enabled, we will update bufReg to point to the actual start of the array data
   // and set offsetToDataElements to zero
#ifdef J9VM_GC_SPARSE_HEAP_ALLOCATION
   if (TR::Compiler->om.isOffHeapAllocationEnabled())
      {
      generateRegMemInstruction(TR::InstOpCode::L8RegMem, node, bufReg, generateX86MemoryReference(bufReg, cg->comp()->fej9()->getOffsetOfContiguousDataAddrField(), cg), cg);

      // We'll be loading first data element address from array header so no need for offset
      offsetToDataElements = 0;
      }
#endif /* J9VM_GC_SPARSE_HEAP_ALLOCATION */

   // index = offset
   generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, indexReg, offsetReg, cg);

   // limit = offset + length
   generateRegMemInstruction(TR::InstOpCode::LEA4RegMem, node, limitReg, generateX86MemoryReference(offsetReg, lengthReg, 0, 0, cg), cg);

   // loopLimit = (length & -16) + offset
   generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, loopLimitReg, lengthReg, cg);
   generateRegImmInstruction(TR::InstOpCode::AND4RegImm4, node, loopLimitReg, -16, cg);
   generateRegRegInstruction(TR::InstOpCode::ADD4RegReg, node, loopLimitReg, offsetReg, cg);

   // If the 16 byte encoding of the pmovmskb instruction is not supported on this architecture,
   // Prepare an 8 byte sign bit mask so we can run an alternate version of the algorithm
   if (!useVectorInstructions)
      {
      generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, maskReg, 0x8080808080808080, cg);
      }


   generateLabelInstruction(TR::InstOpCode::label, node, loopLabel, cg);

   // if index >= loopLimit, jump to handling the residual bytes
   generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, indexReg, loopLimitReg, cg);
   generateLabelInstruction(TR::InstOpCode::JGE4, node, residualLabel, cg);


   // If the 16 byte version of pmovmskb is supported on this architecture,
   // we can proceed to generate code for the loop
   if (useVectorInstructions)
      {
      // Load 16 bytes from address [buf + index]
      generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, xmmChunkReg, generateX86MemoryReference(bufReg, indexReg, 0, offsetToDataElements, cg), cg);

      // Extract bitmask of sign bits
      generateRegRegInstruction(TR::InstOpCode::PMOVMSKB4RegReg, node, maskReg, xmmChunkReg, cg, pmovmskbEncoding);

      // Check if any negative values exist
      generateRegRegInstruction(TR::InstOpCode::TEST2RegReg, node, maskReg, maskReg, cg);
      }
   // If the 16 byte version of pmovmskb is not supported,
   // run an alternate version of the loop with an 8 byte chunk instead of a 16 byte chunk
   else
      {
      // Load 8 bytes from address [buf + index]
      generateRegMemInstruction(TR::InstOpCode::L8RegMem, node, chunkReg, generateX86MemoryReference(bufReg, indexReg, 0, offsetToDataElements, cg), cg);

      // Check if any negative values exist
      generateRegRegInstruction(TR::InstOpCode::TEST8RegReg, node, chunkReg, maskReg, cg);
      }

   // If the result is nonzero, we found at least one negative byte
   generateLabelInstruction(TR::InstOpCode::JNE4,
                            node,
                            isHasNegatives ? returnBooleanLabel : returnHasNegativesLabel,
                            cg);

   // increment index by the appropriate amount and jump back to the top of the loop
   generateRegImmInstruction(TR::InstOpCode::ADD4RegImm4, node, indexReg, useVectorInstructions ? 16 : 8, cg);
   generateLabelInstruction(TR::InstOpCode::JMP4, node, loopLabel, cg);


   // Deal with the residual (last 15 or fewer) bytes
   generateLabelInstruction(TR::InstOpCode::label, node, residualLabel, cg);

   // Calculate bytes remaining: loopLimit = -(loopLimit - limit)
   generateRegRegInstruction(TR::InstOpCode::SUB4RegReg, node, loopLimitReg, limitReg, cg);
   generateRegInstruction(TR::InstOpCode::NEG4Reg, node, loopLimitReg, cg);

   /*
    *    if loopLimit == 0
    *       return result
    *    if loopLimit > 8
    *       jmp nineOrMoreBytesLabel -------+
    *    if loopLimit > 2                   |
    *       jmp threeOrMoreBytesLabel ----+ |
    *                                     | |
    *    load 1-2 bytes                   | |
    *    jmp residualTestLabel            | |
    *                                     | |
    *    threeOrMoreBytesLabel: <---------+ |
    *       if loopLimit > 4                |
    *          jmp fiveOrMoreBytesLabel --+ |
    *                                     | |
    *       load 3-4 bytes                | |
    *       jmp residualTestLabel         | |
    *                                     | |
    *    fiveOrMoreBytesLabel: <----------+ |
    *       load 5-8 Bytes                  |
    *       jmp residualTestLabel           |
    *                                       |
    *    nineOrMoreBytesLabel: <------------+
    *       load 9-16 bytes
    *
    *    residualTestLabel:
    *       AND chunkReg with maskReg
    *
    *    return result
    */

   // if loopLimit = 0, we did not find any negative bytes
   generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, loopLimitReg, loopLimitReg, cg);
   generateLabelInstruction(TR::InstOpCode::JE4,
                            node,
                            isHasNegatives ? returnBooleanLabel : returnNoNegativesLabel,
                            cg);

   // Prepare an 8 byte sign bit mask
   // (if the 16 byte pmovmskb instruction above isn't supported, we already did this at the start)
   if (useVectorInstructions)
      {
      generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, maskReg, 0x8080808080808080, cg);
      }

   // if loopLimit > 8, jump to nineOrMoreBytesLabel
   generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, loopLimitReg, 8, cg);
   generateLabelInstruction(TR::InstOpCode::JG4, node, nineOrMoreBytesLabel, cg);

   // Zero out the chunk register
   generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, chunkReg, chunkReg, cg);

   // if loopLimit > 2, jump to threeOrMoreBytesLabel
   generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, loopLimitReg, 2, cg);
   generateLabelInstruction(TR::InstOpCode::JG4, node, threeOrMoreBytesLabel, cg);


   // Case in which there are one or two residual bytes
   // Load the byte at address [buf + index] into the chunk register
   generateRegMemInstruction(TR::InstOpCode::L1RegMem, node, chunkReg, generateX86MemoryReference(bufReg, indexReg, 0, offsetToDataElements, cg), cg);
   // OR the second byte (which is the same byte again in the 1 byte case)
   generateRegMemInstruction(TR::InstOpCode::OR1RegMem, node, chunkReg, generateX86MemoryReference(bufReg, limitReg, 0, offsetToDataElements - 1, cg), cg);

   generateLabelInstruction(TR::InstOpCode::JMP4, node, residualTestLabel, cg);


   // Case in which there are three or more residual bytes
   generateLabelInstruction(TR::InstOpCode::label, node, threeOrMoreBytesLabel, cg);

   // if loopLimit > 4, jump to fiveOrMoreBytesLabel
   generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, loopLimitReg, 4, cg);
   generateLabelInstruction(TR::InstOpCode::JG4, node, fiveOrMoreBytesLabel, cg);

   // Load the first two bytes at address [buf + index] into the chunk register
   generateRegMemInstruction(TR::InstOpCode::L2RegMem, node, chunkReg, generateX86MemoryReference(bufReg, indexReg, 0, offsetToDataElements, cg), cg);
   // OR the second two bytes at address [buf + (limit - 2)] into the chunk register
   generateRegMemInstruction(TR::InstOpCode::OR2RegMem, node, chunkReg, generateX86MemoryReference(bufReg, limitReg, 0, offsetToDataElements - 2, cg), cg);

   generateLabelInstruction(TR::InstOpCode::JMP4, node, residualTestLabel, cg);


   // Case in which there are five or more residual bytes
   generateLabelInstruction(TR::InstOpCode::label, node, fiveOrMoreBytesLabel, cg);

   // Load the first four bytes at address [buf + index] into the chunk register
   generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, chunkReg, generateX86MemoryReference(bufReg, indexReg, 0, offsetToDataElements, cg), cg);
   // OR the second four bytes at address [buf + (limit - 4)] into the chunk register
   generateRegMemInstruction(TR::InstOpCode::OR4RegMem, node, chunkReg, generateX86MemoryReference(bufReg, limitReg, 0, offsetToDataElements - 4, cg), cg);

   generateLabelInstruction(TR::InstOpCode::JMP4, node, residualTestLabel, cg);


   // Case in which there are nine or more residual bytes
   generateLabelInstruction(TR::InstOpCode::label, node, nineOrMoreBytesLabel, cg);

   // Load the first eight bytes at address [buf + index] into the chunk register
   generateRegMemInstruction(TR::InstOpCode::L8RegMem, node, chunkReg, generateX86MemoryReference(bufReg, indexReg, 0, offsetToDataElements, cg), cg);
   // OR the second eight bytes at address [buf + (limit - 8)] into the chunk register
   generateRegMemInstruction(TR::InstOpCode::OR8RegMem, node, chunkReg, generateX86MemoryReference(bufReg, limitReg, 0, offsetToDataElements - 8, cg), cg);


   // Examine the chunk register now that all of the residual bytes have been ORed into it
   generateLabelInstruction(TR::InstOpCode::label, node, residualTestLabel, cg);
   // AND the residual bytes with the new mask
   generateRegRegInstruction(TR::InstOpCode::TEST8RegReg, node, chunkReg, maskReg, cg);
   if (!isHasNegatives)
      {
      // If the result is nonzero (i.e. at least one of the sign bits is set), jump to returnHasNegativesLabel
      generateLabelInstruction(TR::InstOpCode::JNE4, node, returnHasNegativesLabel, cg);
      }


   // Return result
   if (isHasNegatives)
      {
      generateLabelInstruction(TR::InstOpCode::label, node, returnBooleanLabel, cg);
      // If the result of the previous comparison is nonzero, a negative byte has been found somewhere, so return true
      // Otherwise, return false
      generateRegInstruction(TR::InstOpCode::SETNE1Reg, node, indexReg, cg);
      generateRegRegInstruction(TR::InstOpCode::MOVZXReg4Reg1, node, indexReg, indexReg, cg);
      }
   else
      {
      // no negatives found case, result = length
      generateLabelInstruction(TR::InstOpCode::label, node, returnNoNegativesLabel, cg);
      generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, indexReg, lengthReg, cg);
      generateLabelInstruction(TR::InstOpCode::JMP4, node, endLabel, cg);

      // negative(s) found case, result = index - offset
      generateLabelInstruction(TR::InstOpCode::label, node, returnHasNegativesLabel, cg);
      generateRegRegInstruction(TR::InstOpCode::SUB4RegReg, node, indexReg, offsetReg, cg);
      }


   generateLabelInstruction(TR::InstOpCode::label, node, endLabel, dependencies, cg);

   cg->stopUsingRegister(bufReg);
   cg->stopUsingRegister(loopLimitReg);
   cg->stopUsingRegister(limitReg);
   cg->stopUsingRegister(maskReg);
   cg->stopUsingRegister(chunkReg);
   if (useVectorInstructions)
      {
      cg->stopUsingRegister(xmmChunkReg);
      }

   node->setRegister(indexReg);
   for (int32_t i = 0; i < node->getNumChildren(); i++)
      {
      cg->decReferenceCount(node->getChild(i));
      }
   return indexReg;
   }


// Generate inline code if possible for a call to an inline method. The call
// may be direct or indirect; if it is indirect a guard will be generated around
// the inline code and a fall-back to the indirect call.
// Returns true if the call was inlined, otherwise a regular call sequence must
// be issued by the caller of this method.
//
bool J9::X86::TreeEvaluator::VMinlineCallEvaluator(
      TR::Node *node,
      bool isIndirect,
      TR::CodeGenerator *cg)
   {
   TR::MethodSymbol *methodSymbol = node->getSymbol()->castToMethodSymbol();
   TR::ResolvedMethodSymbol *resolvedMethodSymbol = node->getSymbol()->getResolvedMethodSymbol();

   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());

   bool callWasInlined = false;
   TR::Compilation *comp = cg->comp();

   bool disableCASInlining = !cg->getSupportsInlineUnsafeCompareAndSet();
   bool disableCAEInlining = !cg->getSupportsInlineUnsafeCompareAndExchange();

   if (methodSymbol)
      {
      switch (methodSymbol->getRecognizedMethod())
         {
         case TR::sun_nio_ch_NativeThread_current:
            // The spec says that on systems that do not require signaling
            // that this method should return -1. I'm not sure what do realtime
            // systems do here
            if (!comp->getOptions()->realTimeGC() && node->getNumChildren()>0)
               {
               TR::Register *nativeThreadReg = cg->allocateRegister();
               TR::Register *nativeThreadRegHigh = NULL;
               TR::Register *vmThreadReg = cg->getVMThreadRegister();
               int32_t numDeps = 2;

               if (comp->target().is32Bit())
                  {
                  nativeThreadRegHigh = cg->allocateRegister();
                  numDeps ++;
                  }

               TR::RegisterDependencyConditions  *deps = generateRegisterDependencyConditions((uint8_t)0, (uint8_t)numDeps, cg);
               deps->addPostCondition(nativeThreadReg, TR::RealRegister::NoReg, cg);
               if (comp->target().is32Bit())
                  {
                  deps->addPostCondition(nativeThreadRegHigh, TR::RealRegister::NoReg, cg);
                  }
               deps->addPostCondition(vmThreadReg, TR::RealRegister::ebp, cg);

               if (comp->target().is64Bit())
                  {
                  TR::LabelSymbol *startLabel = generateLabelSymbol(cg);
                  TR::LabelSymbol *doneLabel = generateLabelSymbol(cg);
                  startLabel->setStartInternalControlFlow();
                  generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

                  generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, nativeThreadReg,
                                         generateX86MemoryReference(vmThreadReg, fej9->thisThreadOSThreadOffset(), cg), cg);
                  generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, nativeThreadReg,
                                                           generateX86MemoryReference(nativeThreadReg, offsetof(J9Thread, handle), cg), cg);
                  doneLabel->setEndInternalControlFlow();
                  generateLabelInstruction(TR::InstOpCode::label, node, doneLabel, deps, cg);
                  }
               else
                  {
                  TR::MemoryReference *lowMR = generateX86MemoryReference(vmThreadReg, fej9->thisThreadOSThreadOffset(), cg);
                  TR::MemoryReference *highMR = generateX86MemoryReference(*lowMR, 4, cg);

                  TR::LabelSymbol *startLabel = generateLabelSymbol(cg);
                  TR::LabelSymbol *doneLabel = generateLabelSymbol(cg);
                  startLabel->setStartInternalControlFlow();
                  generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

                  generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, nativeThreadReg, lowMR, cg);
                  generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, nativeThreadRegHigh, highMR, cg);

                  TR::MemoryReference *lowHandleMR = generateX86MemoryReference(nativeThreadReg, offsetof(J9Thread, handle), cg);
                  TR::MemoryReference *highHandleMR = generateX86MemoryReference(*lowMR, 4, cg);

                  generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, nativeThreadReg, lowHandleMR, cg);
                  generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, nativeThreadRegHigh, highHandleMR, cg);

                  doneLabel->setEndInternalControlFlow();
                  generateLabelInstruction(TR::InstOpCode::label, node, doneLabel, deps, cg);
                  }

               if (comp->target().is32Bit())
                  {
                  TR::RegisterPair *longRegister = cg->allocateRegisterPair(nativeThreadReg, nativeThreadRegHigh);
                  node->setRegister(longRegister);
                  }
               else
                  {
                  node->setRegister(nativeThreadReg);
                  }
               cg->recursivelyDecReferenceCount(node->getFirstChild());
               return true;
               }
            return false; // Call the native version of NativeThread.current()
         case TR::sun_misc_Unsafe_compareAndSwapInt_jlObjectJII_Z:
            {
            if (!disableCASInlining && node->isSafeForCGToFastPathUnsafeCall())
               return inlineCompareAndSwapNative(node, 4, false, false, cg);
            }
            break;
         case TR::sun_misc_Unsafe_compareAndSwapLong_jlObjectJJJ_Z:
            {
            if (!disableCASInlining && node->isSafeForCGToFastPathUnsafeCall())
               return inlineCompareAndSwapNative(node, 8, false, false, cg);
            }
            break;
         case TR::sun_misc_Unsafe_compareAndSwapObject_jlObjectJjlObjectjlObject_Z:
            {
            static bool useOldCompareAndSwapObject = (bool)feGetEnv("TR_UseOldCompareAndSwapObject");
            if (!disableCASInlining && node->isSafeForCGToFastPathUnsafeCall())
               {
               if (useOldCompareAndSwapObject)
                  return inlineCompareAndSwapNative(node, TR::Compiler->om.sizeofReferenceField(), true, false, cg);
               else
                  {
                  inlineCompareAndSwapObjectNative(node, cg, false);
                  return true;
                  }
               }
            }
            break;
         case TR::jdk_internal_misc_Unsafe_compareAndExchangeInt:
            {
            if (!disableCAEInlining && node->isSafeForCGToFastPathUnsafeCall())
               return inlineCompareAndSwapNative(node, 4, false, true, cg);
            }
            break;
         case TR::jdk_internal_misc_Unsafe_compareAndExchangeLong:
            {
            if (!disableCAEInlining && node->isSafeForCGToFastPathUnsafeCall())
               return inlineCompareAndSwapNative(node, 8, false, true, cg);
            }
            break;
         case TR::jdk_internal_misc_Unsafe_compareAndExchangeObject:
         case TR::jdk_internal_misc_Unsafe_compareAndExchangeReference:
            {
            static bool useOldCompareAndSwapObject = (bool)feGetEnv("TR_UseOldCompareAndSwapObject");
            if (!disableCAEInlining && node->isSafeForCGToFastPathUnsafeCall())
               {
               if (useOldCompareAndSwapObject)
                  return inlineCompareAndSwapNative(node, TR::Compiler->om.sizeofReferenceField(), true, true, cg);
               else
                  {
                  inlineCompareAndSwapObjectNative(node, cg, true);
                  return true;
                  }
               }
            }
            break;

        case TR::java_lang_Object_clone:
           {
           return (objectCloneEvaluator(node, cg) != NULL);
           break;
           }
        default:
           break;
         }
      }

   if (!resolvedMethodSymbol)
      return false;

   if (resolvedMethodSymbol)
      {
      switch (resolvedMethodSymbol->getRecognizedMethod())
         {
#ifdef LINUX
         case TR::java_lang_System_nanoTime:
            {
            TR_ASSERT(!isIndirect, "Indirect call to nanoTime");
            callWasInlined = inlineNanoTime(node, cg);
            break;
            }
#endif
         default:
            break;
         }
      }

   return callWasInlined;
   }


/**
 * \brief
 *   Generate instructions to conditionally branch to a write barrier helper call
 *
 * \oaram branchOp
 *   The branch instruction to jump to the write barrier helper call
 *
 * \param node
 *   The write barrier node
 *
 * \param gcMode
 *   The GC Mode
 *
 * \param owningObjectReg
 *   The register holding the owning object
 *
 * \param sourceReg
 *   The register holding the source object
 *
 * \param doneLabel
 *   The label to jump to when returning from the write barrier helper
 *
 * \param cg
 *   The Code Generator
 *
 * Note that RealTimeGC is handled separately in a different method.
 */
static void generateWriteBarrierCall(
   TR::InstOpCode::Mnemonic          branchOp,
   TR::Node*              node,
    MM_GCWriteBarrierType gcMode,
   TR::Register*          owningObjectReg,
   TR::Register*          sourceReg,
   TR::LabelSymbol*       doneLabel,
   TR::CodeGenerator*     cg)
   {
   TR::Compilation *comp = cg->comp();
   TR_ASSERT(gcMode != gc_modron_wrtbar_satb && !comp->getOptions()->realTimeGC(), "This helper is not for RealTimeGC.");

   uint8_t helperArgCount = 0;  // Number of arguments passed on the runtime helper.
   TR::SymbolReference *wrtBarSymRef = NULL;

   if (node->getOpCodeValue() == TR::arraycopy)
      {
      wrtBarSymRef = comp->getSymRefTab()->findOrCreateWriteBarrierBatchStoreSymbolRef();
      helperArgCount = 1;
      }
   else if (gcMode == gc_modron_wrtbar_cardmark_and_oldcheck)
      {
      wrtBarSymRef = comp->getSymRefTab()->findOrCreateWriteBarrierStoreGenerationalAndConcurrentMarkSymbolRef();
      helperArgCount = 2;
      }
   else if (gcMode == gc_modron_wrtbar_always)
      {
      wrtBarSymRef = comp->getSymRefTab()->findOrCreateWriteBarrierStoreSymbolRef();
      helperArgCount = 2;
      }
   else if (comp->generateArraylets())
      {
      wrtBarSymRef = comp->getSymRefTab()->findOrCreateWriteBarrierStoreSymbolRef();
      helperArgCount = 2;
      }
   else
      {
      // Default case is a generational barrier (non-concurrent).
      //
      wrtBarSymRef = comp->getSymRefTab()->findOrCreateWriteBarrierStoreGenerationalSymbolRef();
      helperArgCount = 2;
      }

   TR::LabelSymbol* wrtBarLabel = generateLabelSymbol(cg);

   generateLabelInstruction(branchOp, node, wrtBarLabel, cg);

   TR_OutlinedInstructionsGenerator og(wrtBarLabel, node, cg);

   generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, floatTemp1), cg), owningObjectReg, cg);
   if (helperArgCount > 1)
      {
      generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, floatTemp2), cg), sourceReg, cg);
      }
   generateImmSymInstruction(TR::InstOpCode::CALLImm4, node, (uintptr_t)wrtBarSymRef->getMethodAddress(), wrtBarSymRef, cg);
   generateLabelInstruction(TR::InstOpCode::JMP4, node, doneLabel, cg);

   og.endOutlinedInstructionSequence();
   }

static void reportFlag(bool value, char *name, TR::CodeGenerator *cg)
   {
   if (value)
      traceMsg(cg->comp(), " %s", name);
   }

static int32_t byteOffsetForMask(int32_t mask, TR::CodeGenerator *cg)
   {
   int32_t result;
   for (result = 3; result >= 0; --result)
      {
      int32_t shift = 8*result;
      if ( ((mask>>shift)<<shift) == mask )
         break;
      }

   if (result != -1
      && performTransformation(cg->comp(), "O^O TREE EVALUATION: Use 1-byte TEST with offset %d for mask %08x\n", result, mask))
      return result;

   return -1;
   }


#define REPORT_FLAG(name) reportFlag((name), #name, cg)

void J9::X86::TreeEvaluator::VMwrtbarRealTimeWithoutStoreEvaluator(
   TR::Node                   *node,
   TR::MemoryReference *storeMRForRealTime,          // RTJ only
   TR::Register               *storeAddressRegForRealTime,  // RTJ only
   TR::Node                   *destOwningObject, // only NULL for ME, always evaluated except for AC (evaluated below)
   TR::Node                   *sourceObject,     // NULL for ME and AC(Array Copy?)
   TR::Register               *srcReg,           // should only be provided when sourceObject == NULL  (ME Multimidlet)
   TR_X86ScratchRegisterManager *srm,
   TR::CodeGenerator          *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());
   TR_ASSERT(comp->getOptions()->realTimeGC(),"Call the non real-time barrier");
   auto gcMode = TR::Compiler->om.writeBarrierType();

   if (node->getOpCode().isWrtBar() && node->skipWrtBar())
      gcMode = gc_modron_wrtbar_none;
   else if ((node->getOpCodeValue() == TR::ArrayStoreCHK) &&
            node->getFirstChild()->getOpCode().isWrtBar() &&
            node->getFirstChild()->skipWrtBar())
      gcMode = gc_modron_wrtbar_none;

   // PR98283: it is not acceptable to emit a label symbol twice so always generate a new label here
   // we can clean up the API later in a less risky manner
   TR::LabelSymbol *doneLabel = generateLabelSymbol(cg);

   // srcReg could only be NULL at this point for arraycopy
   if (sourceObject)
      {
      TR_ASSERT(!srcReg, "assertion failure");
      srcReg = sourceObject->getRegister();
      TR_ASSERT(srcReg, "assertion failure");
      }   //

   TR::Node *wrtbarNode;
   switch (node->getOpCodeValue())
      {
      case TR::ArrayStoreCHK:
         wrtbarNode = node->getFirstChild();
         break;
      case TR::arraycopy:
         wrtbarNode = NULL;
         break;
      case TR::awrtbari:
      case TR::awrtbar:
         wrtbarNode = node;
         break;
      default:
         wrtbarNode = NULL;
         break;
      }

   bool doInternalControlFlow;

   if (node->getOpCodeValue() == TR::ArrayStoreCHK)
      {
      // TR::ArrayStoreCHK will create its own internal control flow.
      //
      doInternalControlFlow = false;
      }
   else
      {
      doInternalControlFlow = true;
      }

   if (comp->getOption(TR_TraceCG) /*&& comp->getOption(TR_TraceOptDetails)*/)
      {
      traceMsg(comp, " | Real Time Write barrier info:\n");
      traceMsg(comp, " |   GC mode = %d:%s\n", gcMode, cg->getDebug()->getWriteBarrierKindName(gcMode));
      traceMsg(comp, " |   Node = %s %s  sourceObject = %s\n",
         cg->getDebug()->getName(node->getOpCodeValue()),
         cg->getDebug()->getName(node),
         sourceObject? cg->getDebug()->getName(sourceObject) : "(none)");
      traceMsg(comp, " |   Action flags:");
         REPORT_FLAG(doInternalControlFlow);
      traceMsg(comp, "\n");
      }

   //
   // Phase 2: Generate the appropriate code.
   //
   TR::Register *owningObjectReg;
   TR::Register *tempReg = NULL;

   owningObjectReg = cg->evaluate(destOwningObject);

   if (doInternalControlFlow)
      {
      TR::LabelSymbol *startLabel = generateLabelSymbol(cg);
      startLabel->setStartInternalControlFlow();
      generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);
      doneLabel->setEndInternalControlFlow();
      }

   if (comp->getOption(TR_BreakOnWriteBarrier))
      {
      generateInstruction(TR::InstOpCode::INT3, node, cg);
      }

   TR::SymbolReference *wrtBarSymRef = NULL;
   if (wrtbarNode && (wrtbarNode->getOpCodeValue()==TR::awrtbar || wrtbarNode->isUnsafeStaticWrtBar()))
      wrtBarSymRef = comp->getSymRefTab()->findOrCreateWriteBarrierClassStoreRealTimeGCSymbolRef();
   else
      wrtBarSymRef = comp->getSymRefTab()->findOrCreateWriteBarrierStoreRealTimeGCSymbolRef();

   TR::LabelSymbol *snippetLabel = generateLabelSymbol(cg);

   // TR IL doesn't have a way to express the address of a field in an object, so we need some sneakiness here:
   //   1) create a dummy node for this argument to the call
   //   2) explicitly set that node's register to storeAddressRegForRealTime, preventing it from being evaluated
   //      (will just push storeAddressRegForRealTime for the call)
   //
   TR::Node *dummyDestAddressNode = TR::Node::create(node, TR::aconst, 0, 0);
   dummyDestAddressNode->setRegister(storeAddressRegForRealTime);
   TR::Node *callNode = TR::Node::createWithSymRef(TR::call, 3, 3, sourceObject, dummyDestAddressNode, destOwningObject, wrtBarSymRef);

   if (comp->getOption(TR_DisableInlineWriteBarriersRT))
      {
      cg->evaluate(callNode);
      }
   else
      {
      TR_OutlinedInstructions *outlinedHelperCall = new (cg->trHeapMemory()) TR_OutlinedInstructions(callNode, TR::call, NULL, snippetLabel, doneLabel, cg);

      // have to disassemble the call node we just created, first have to give it a ref count 1
      callNode->setReferenceCount(1);
      cg->recursivelyDecReferenceCount(callNode);

      cg->getOutlinedInstructionsList().push_front(outlinedHelperCall);
      cg->generateDebugCounter(
            outlinedHelperCall->getFirstInstruction(),
            TR::DebugCounter::debugCounterName(comp, "helperCalls/%s/(%s)/%d/%d", node->getOpCode().getName(), comp->signature(), node->getByteCodeInfo().getCallerIndex(), node->getByteCodeInfo().getByteCodeIndex()),
            1, TR::DebugCounter::Cheap);

      if (comp->getOption(TR_CountWriteBarriersRT))
         {
         TR::MemoryReference *barrierCountMR = generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, debugEventData6), cg);
         generateMemInstruction(TR::InstOpCode::INCMem(comp->target().is64Bit()), node, barrierCountMR, cg);
         }

      tempReg = srm->findOrCreateScratchRegister();

      // if barrier not enabled, nothing to do
      TR::MemoryReference *fragmentParentMR = generateX86MemoryReference(cg->getVMThreadRegister(), fej9->thisThreadRememberedSetFragmentOffset() + fej9->getFragmentParentOffset(), cg);
      generateRegMemInstruction(TR::InstOpCode::LRegMem(comp->target().is64Bit()), node, tempReg, fragmentParentMR, cg);
      TR::MemoryReference *globalFragmentIDMR = generateX86MemoryReference(tempReg, fej9->getRememberedSetGlobalFragmentOffset(), cg);
      generateMemImmInstruction(TR::InstOpCode::CMPMemImms(), node, globalFragmentIDMR, 0, cg);
      generateLabelInstruction(TR::InstOpCode::JE4, node, doneLabel, cg);

      // now check if double barrier is enabled and definitely execute the barrier if it is
      // if (vmThread->localFragmentIndex == 0) goto snippetLabel
      TR::MemoryReference *localFragmentIndexMR = generateX86MemoryReference(cg->getVMThreadRegister(), fej9->thisThreadRememberedSetFragmentOffset() + fej9->getLocalFragmentOffset(), cg);
      generateMemImmInstruction(TR::InstOpCode::CMPMemImms(), node, localFragmentIndexMR, 0, cg);
      generateLabelInstruction(TR::InstOpCode::JE4, node, snippetLabel, cg);

      // null test on the reference we're about to store over: if it is null goto doneLabel
      // if (destObject->field == null) goto doneLabel
      TR::MemoryReference *nullTestMR = generateX86MemoryReference(storeAddressRegForRealTime, 0, cg);
      if (comp->target().is64Bit() && comp->useCompressedPointers())
         generateMemImmInstruction(TR::InstOpCode::CMP4MemImms, node, nullTestMR, 0, cg);
      else
         generateMemImmInstruction(TR::InstOpCode::CMPMemImms(), node, nullTestMR, 0, cg);
      generateLabelInstruction(TR::InstOpCode::JNE4, node, snippetLabel, cg);

      // fall-through means write barrier not needed, just do the store
      }

   if (doInternalControlFlow)
      {
      int32_t numPostConditions = 2 + srm->numAvailableRegisters();

      numPostConditions += 4;

      if (srcReg)
         {
         numPostConditions++;
         }

      TR::RegisterDependencyConditions *conditions =
         generateRegisterDependencyConditions((uint8_t) 0, numPostConditions, cg);

      conditions->addPostCondition(owningObjectReg, TR::RealRegister::NoReg, cg);
      if (srcReg)
         {
         conditions->addPostCondition(srcReg, TR::RealRegister::NoReg, cg);
         }

      conditions->addPostCondition(cg->getVMThreadRegister(), TR::RealRegister::ebp, cg);

      if (!comp->getOption(TR_DisableInlineWriteBarriersRT))
         {
         TR_ASSERT(storeAddressRegForRealTime != NULL, "assertion failure");
         conditions->addPostCondition(storeAddressRegForRealTime, TR::RealRegister::NoReg, cg);

         TR_ASSERT(tempReg != NULL, "assertion failure");
         conditions->addPostCondition(tempReg, TR::RealRegister::NoReg, cg);
         }

      if (destOwningObject->getOpCode().hasSymbolReference()
       && destOwningObject->getSymbol()
       && !destOwningObject->getSymbol()->isLocalObject())
         {
         if (storeMRForRealTime->getBaseRegister())
            {
            conditions->unionPostCondition(storeMRForRealTime->getBaseRegister(), TR::RealRegister::NoReg, cg);
            }
         if (storeMRForRealTime->getIndexRegister())
            {
            conditions->unionPostCondition(storeMRForRealTime->getIndexRegister(), TR::RealRegister::NoReg, cg);
            }
         }

      srm->addScratchRegistersToDependencyList(conditions);
      conditions->stopAddingConditions();

      generateLabelInstruction(TR::InstOpCode::label, node, doneLabel, conditions, cg);

      srm->stopUsingRegisters();
      }
   else
      {
      TR_ASSERT(node->getOpCodeValue() == TR::ArrayStoreCHK, "assertion failure");
      generateLabelInstruction(TR::InstOpCode::label, node, doneLabel, cg);
      }
  }




void J9::X86::TreeEvaluator::VMwrtbarWithoutStoreEvaluator(
   TR::Node                   *node,
   TR::Node                   *destOwningObject, // only NULL for ME, always evaluated except for AC (evaluated below)
   TR::Node                   *sourceObject,     // NULL for ME and AC(Array Copy?)
   TR::Register               *srcReg,           // should only be provided when sourceObject == NULL  (ME Multimidlet)
   TR_X86ScratchRegisterManager *srm,
   TR::CodeGenerator          *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());
   TR_ASSERT(!(comp->getOptions()->realTimeGC()),"Call the real-time barrier");
   auto gcMode = TR::Compiler->om.writeBarrierType();

   if (node->getOpCode().isWrtBar() && node->skipWrtBar())
      gcMode = gc_modron_wrtbar_none;
   else if ((node->getOpCodeValue() == TR::ArrayStoreCHK) &&
            node->getFirstChild()->getOpCode().isWrtBar() &&
            node->getFirstChild()->skipWrtBar())
      gcMode = gc_modron_wrtbar_none;

   // PR98283: it is not acceptable to emit a label symbol twice so always generate a new label here
   // we can clean up the API later in a less risky manner
   TR::LabelSymbol *doneLabel = generateLabelSymbol(cg);

   TR::LabelSymbol *cardMarkDoneLabel = NULL;

   bool isSourceNonNull;

   // If a source node is provided, derive the source object register from it.
   // The source node must be evaluated before this function is called so it must
   // always be in a register.
   //
   if (sourceObject)
      {
      TR_ASSERT(!srcReg, "assertion failure");
      srcReg = sourceObject->getRegister();
      TR_ASSERT(srcReg, "assertion failure");
      isSourceNonNull = sourceObject->isNonNull();
      }
   else
      {
      isSourceNonNull = false;
      }


   // srcReg could only be NULL at this point for arraycopy

   //
   // Phase 1: Decide what parts of this logic we need to do
   //

   TR::Node *wrtbarNode;
   switch (node->getOpCodeValue())
      {
      case TR::ArrayStoreCHK:
         wrtbarNode = node->getFirstChild();
         break;
      case TR::arraycopy:
         wrtbarNode = NULL;
         break;
      case TR::awrtbari:
      case TR::awrtbar:
         wrtbarNode = node;
         break;
      default:
         wrtbarNode = NULL;
         break;
      }

   bool doInlineCardMarkingWithoutOldSpaceCheck, doIsDestAHeapObjectCheck;

   if (wrtbarNode)
      {
      TR_ASSERT(wrtbarNode->getOpCode().isWrtBar(), "Expected node " POINTER_PRINTF_FORMAT " to be a WrtBar", wrtbarNode);
      // Note: for gc_modron_wrtbar_cardmark_and_oldcheck we let the helper do the card mark (ie. we don't inline it)
      doInlineCardMarkingWithoutOldSpaceCheck =
         (gcMode == gc_modron_wrtbar_cardmark || gcMode == gc_modron_wrtbar_cardmark_incremental)
         && !wrtbarNode->getSymbol()->isLocalObject()
         && !wrtbarNode->isNonHeapObjectWrtBar();

      doIsDestAHeapObjectCheck = doInlineCardMarkingWithoutOldSpaceCheck && !wrtbarNode->isHeapObjectWrtBar();
      }
   else
      {
      // TR::arraycopy or TR::ArrayStoreCHK
      //
      // Old space checks will be done out-of-line, and if a card mark policy requires an old space check
      // as well then both will be done out-of-line.
      //
      doInlineCardMarkingWithoutOldSpaceCheck = doIsDestAHeapObjectCheck = (gcMode == gc_modron_wrtbar_cardmark || gcMode == gc_modron_wrtbar_cardmark_incremental);
      }


// for Tarok  gc_modron_wrtbar_cardmark
//
//   doIsDestAHeapObjectCheck = true (if req)   OK
//   doIsDestInOldSpaceCheck = false            OK
//   doInlineCardMarkingWithoutOldSpaceCheck = maybe  OK
//   doCheckConcurrentMarkActive = false        OK
//   dirtyCardTableOutOfLine = false            OK


   bool doIsDestInOldSpaceCheck =
         gcMode == gc_modron_wrtbar_oldcheck
      || gcMode == gc_modron_wrtbar_cardmark_and_oldcheck
      || gcMode == gc_modron_wrtbar_always
      ;

   bool unsafeCallBarrier = false;
   if (doIsDestInOldSpaceCheck &&
       (gcMode == gc_modron_wrtbar_cardmark
       || gcMode == gc_modron_wrtbar_cardmark_and_oldcheck
       || gcMode == gc_modron_wrtbar_cardmark_incremental) &&
       node->getOpCode().isCall())
      {
      TR::MethodSymbol *symbol = node->getSymbol()->castToMethodSymbol();
      if (symbol &&
          (symbol->getRecognizedMethod() == TR::sun_misc_Unsafe_compareAndSwapObject_jlObjectJjlObjectjlObject_Z ||
           symbol->getRecognizedMethod() == TR::jdk_internal_misc_Unsafe_compareAndExchangeObject ||
           symbol->getRecognizedMethod() == TR::jdk_internal_misc_Unsafe_compareAndExchangeReference))
         {
         unsafeCallBarrier = true;
         }
      }

   bool doCheckConcurrentMarkActive =
         (gcMode == gc_modron_wrtbar_cardmark
       || gcMode == gc_modron_wrtbar_cardmark_and_oldcheck
       || gcMode == gc_modron_wrtbar_cardmark_incremental
       ) && (doInlineCardMarkingWithoutOldSpaceCheck || (doIsDestInOldSpaceCheck && wrtbarNode) || unsafeCallBarrier);

   // Use out-of-line instructions to dirty the card table.
   //
   bool dirtyCardTableOutOfLine = true;

   if (gcMode == gc_modron_wrtbar_cardmark_incremental)
      {
      // Override these settings for policies that don't support concurrent mark.
      //
      doCheckConcurrentMarkActive = false;
      dirtyCardTableOutOfLine = false;
      }

   // For practical applications, adding an explicit test for NULL is not worth the pathlength cost
   // especially since storing null values is not the dominant case.
   //
   static char *doNullCheckOnWrtBar = feGetEnv("TR_doNullCheckOnWrtBar");
   bool doSrcIsNullCheck = (doNullCheckOnWrtBar && doIsDestInOldSpaceCheck && srcReg && !isSourceNonNull);

   bool doInternalControlFlow;

   if (node->getOpCodeValue() == TR::ArrayStoreCHK)
      {
      // TR::ArrayStoreCHK will create its own internal control flow.
      //
      doInternalControlFlow = false;
      }
   else
      {
      doInternalControlFlow =
            (doIsDestInOldSpaceCheck
         || doIsDestAHeapObjectCheck
         || doCheckConcurrentMarkActive
         || doSrcIsNullCheck);
      }

   if (comp->getOption(TR_TraceCG) /*&& comp->getOption(TR_TraceOptDetails)*/)
      {
      traceMsg(comp, " | Write barrier info:\n");
      traceMsg(comp, " |   GC mode = %d:%s\n", gcMode, cg->getDebug()->getWriteBarrierKindName(gcMode));
      traceMsg(comp, " |   Node = %s %s  sourceObject = %s\n",
         cg->getDebug()->getName(node->getOpCodeValue()),
         cg->getDebug()->getName(node),
         sourceObject? cg->getDebug()->getName(sourceObject) : "(none)");
      traceMsg(comp, " |   Action flags:");
         REPORT_FLAG(doInternalControlFlow);
         REPORT_FLAG(doCheckConcurrentMarkActive);
         REPORT_FLAG(doInlineCardMarkingWithoutOldSpaceCheck);
         REPORT_FLAG(dirtyCardTableOutOfLine);
         REPORT_FLAG(doIsDestAHeapObjectCheck);
         REPORT_FLAG(doIsDestInOldSpaceCheck);
         REPORT_FLAG(isSourceNonNull);
         REPORT_FLAG(doSrcIsNullCheck);
      traceMsg(comp, "\n");
      }

   //
   // Phase 2: Generate the appropriate code.
   //
   TR::Register *owningObjectReg;
   TR::Register *tempReg = NULL;

#if defined(J9VM_GC_SPARSE_HEAP_ALLOCATION)
   bool stopUsingCopyBaseReg;
   if (gcMode == gc_modron_wrtbar_cardmark_incremental && TR::Compiler->om.isOffHeapAllocationEnabled() && destOwningObject->isDataAddrPointer())
      owningObjectReg = cg->evaluate(destOwningObject->getFirstChild());
   else
#endif /* defined(J9VM_GC_SPARSE_HEAP_ALLOCATION) */
      owningObjectReg = cg->evaluate(destOwningObject);

   if (doInternalControlFlow)
      {
      TR::LabelSymbol *startLabel = generateLabelSymbol(cg);
      startLabel->setStartInternalControlFlow();
      generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);
      doneLabel->setEndInternalControlFlow();
      }

   if (comp->getOption(TR_BreakOnWriteBarrier))
      {
      generateInstruction(TR::InstOpCode::INT3, node, cg);
      }

   TR::MemoryReference *fragmentParentMR = generateX86MemoryReference(cg->getVMThreadRegister(), fej9->thisThreadRememberedSetFragmentOffset() + fej9->getFragmentParentOffset(), cg);
   TR::MemoryReference *localFragmentIndexMR = generateX86MemoryReference(cg->getVMThreadRegister(), fej9->thisThreadRememberedSetFragmentOffset() + fej9->getLocalFragmentOffset(), cg);
   TR_OutlinedInstructions *inlineCardMarkPath = NULL;
   if (doInlineCardMarkingWithoutOldSpaceCheck && doCheckConcurrentMarkActive)
      {
      TR::MemoryReference *vmThreadPrivateFlagsMR = generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, privateFlags), cg);
      generateMemImmInstruction(TR::InstOpCode::TEST4MemImm4, node, vmThreadPrivateFlagsMR, J9_PRIVATE_FLAGS_CONCURRENT_MARK_ACTIVE, cg);

      // Branch to outlined instructions to inline card dirtying.
      //
      TR::LabelSymbol *inlineCardMarkLabel = generateLabelSymbol(cg);

      generateLabelInstruction(TR::InstOpCode::JNE4, node, inlineCardMarkLabel, cg);

      // Dirty the card table.
      //
      TR_OutlinedInstructionsGenerator og(inlineCardMarkLabel, node, cg);
      TR::Register *tempReg = srm->findOrCreateScratchRegister();

      generateRegRegInstruction(TR::InstOpCode::MOVRegReg(),  node, tempReg, owningObjectReg, cg);

      if (comp->getOptions()->isVariableHeapBaseForBarrierRange0())
         {
         TR::MemoryReference *vhbMR =
         generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, heapBaseForBarrierRange0), cg);
         generateRegMemInstruction(TR::InstOpCode::SUBRegMem(), node, tempReg, vhbMR, cg);
         }
      else
         {
         uintptr_t chb = comp->getOptions()->getHeapBaseForBarrierRange0();

         if (comp->target().is64Bit() && (!IS_32BIT_SIGNED(chb) || TR::Compiler->om.nativeAddressesCanChangeSize()))
            {
            TR::Register *chbReg = srm->findOrCreateScratchRegister();
            generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, chbReg, chb, cg, TR_HEAP_BASE_FOR_BARRIER_RANGE);
            generateRegRegInstruction(TR::InstOpCode::SUBRegReg(), node, tempReg, chbReg, cg);
            srm->reclaimScratchRegister(chbReg);
            }
         else
            {
            generateRegImmInstruction(TR::InstOpCode::SUBRegImm4(), node, tempReg, (int32_t)chb, cg, TR_HEAP_BASE_FOR_BARRIER_RANGE);
            }
         }

      if (doIsDestAHeapObjectCheck)
         {
         cardMarkDoneLabel = doIsDestInOldSpaceCheck ? generateLabelSymbol(cg) : doneLabel;

         if (comp->getOptions()->isVariableHeapSizeForBarrierRange0())
            {
            TR::MemoryReference *vhsMR =
               generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, heapSizeForBarrierRange0), cg);
            generateRegMemInstruction(TR::InstOpCode::CMPRegMem(), node, tempReg, vhsMR, cg);
            }
         else
            {
            uintptr_t chs = comp->getOptions()->getHeapSizeForBarrierRange0();

            if (comp->target().is64Bit() && (!IS_32BIT_SIGNED(chs) || TR::Compiler->om.nativeAddressesCanChangeSize()))
               {
               TR::Register *chsReg = srm->findOrCreateScratchRegister();
               generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, chsReg, chs, cg, TR_HEAP_SIZE_FOR_BARRIER_RANGE);
               generateRegRegInstruction(TR::InstOpCode::CMPRegReg(), node, tempReg, chsReg, cg);
               srm->reclaimScratchRegister(chsReg);
               }
            else
               {
               generateRegImmInstruction(TR::InstOpCode::CMPRegImm4(), node, tempReg, (int32_t)chs, cg, TR_HEAP_SIZE_FOR_BARRIER_RANGE);
               }
            }

         generateLabelInstruction(TR::InstOpCode::JAE4, node, cardMarkDoneLabel, cg);
         }

      generateRegImmInstruction(TR::InstOpCode::SHRRegImm1(), node, tempReg, comp->getOptions()->getHeapAddressToCardAddressShift(), cg);

      // Mark the card
      //
      const uint8_t dirtyCard = 1;

      TR::MemoryReference *cardTableMR;

      if (comp->getOptions()->isVariableActiveCardTableBase())
         {
         TR::MemoryReference *actbMR =
            generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, activeCardTableBase), cg);
         generateRegMemInstruction(TR::InstOpCode::ADDRegMem(), node, tempReg, actbMR, cg);
         cardTableMR = generateX86MemoryReference(tempReg, 0, cg);
         }
      else
         {
         uintptr_t actb = comp->getOptions()->getActiveCardTableBase();

         if (comp->target().is64Bit() && (!IS_32BIT_SIGNED(actb) || TR::Compiler->om.nativeAddressesCanChangeSize()))
            {
            TR::Register *tempReg3 = srm->findOrCreateScratchRegister();
               generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, tempReg3, actb, cg, TR_ACTIVE_CARD_TABLE_BASE);
            cardTableMR = generateX86MemoryReference(tempReg3, tempReg, 0, cg);
            srm->reclaimScratchRegister(tempReg3);
            }
         else
            {
            cardTableMR = generateX86MemoryReference(NULL, tempReg, 0, (int32_t)actb, cg);
            cardTableMR->setReloKind(TR_ACTIVE_CARD_TABLE_BASE);
            }
         }

      generateMemImmInstruction(TR::InstOpCode::S1MemImm1, node, cardTableMR, dirtyCard, cg);
      srm->reclaimScratchRegister(tempReg);
      generateLabelInstruction(TR::InstOpCode::JMP4, node, doneLabel, cg);

      og.endOutlinedInstructionSequence();
      }
   else if (doInlineCardMarkingWithoutOldSpaceCheck && !dirtyCardTableOutOfLine)
      {
      // Dirty the card table.
      //
      TR::Register *tempReg = srm->findOrCreateScratchRegister();

      generateRegRegInstruction(TR::InstOpCode::MOVRegReg(),  node, tempReg, owningObjectReg, cg);

      if (comp->getOptions()->isVariableHeapBaseForBarrierRange0())
         {
         TR::MemoryReference *vhbMR =
         generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, heapBaseForBarrierRange0), cg);
         generateRegMemInstruction(TR::InstOpCode::SUBRegMem(), node, tempReg, vhbMR, cg);
         }
      else
         {
         uintptr_t chb = comp->getOptions()->getHeapBaseForBarrierRange0();

         if (comp->target().is64Bit() && (!IS_32BIT_SIGNED(chb) || TR::Compiler->om.nativeAddressesCanChangeSize()))
            {
            TR::Register *chbReg = srm->findOrCreateScratchRegister();
            generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, chbReg, chb, cg, TR_HEAP_BASE_FOR_BARRIER_RANGE);
            generateRegRegInstruction(TR::InstOpCode::SUBRegReg(), node, tempReg, chbReg, cg);
            srm->reclaimScratchRegister(chbReg);
            }
         else
            {
            generateRegImmInstruction(TR::InstOpCode::SUBRegImm4(), node, tempReg, (int32_t)chb, cg, TR_HEAP_BASE_FOR_BARRIER_RANGE);
            }
         }

      if (doIsDestAHeapObjectCheck)
         {
         cardMarkDoneLabel = doIsDestInOldSpaceCheck ? generateLabelSymbol(cg) : doneLabel;

         if (comp->getOptions()->isVariableHeapSizeForBarrierRange0())
            {
            TR::MemoryReference *vhsMR =
               generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, heapSizeForBarrierRange0), cg);
            generateRegMemInstruction(TR::InstOpCode::CMPRegMem(), node, tempReg, vhsMR, cg);
            }
         else
            {
            uintptr_t chs = comp->getOptions()->getHeapSizeForBarrierRange0();

            if (comp->target().is64Bit() && (!IS_32BIT_SIGNED(chs) || TR::Compiler->om.nativeAddressesCanChangeSize()))
               {
               TR::Register *chsReg = srm->findOrCreateScratchRegister();
               generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, chsReg, chs, cg, TR_HEAP_SIZE_FOR_BARRIER_RANGE);
               generateRegRegInstruction(TR::InstOpCode::CMPRegReg(), node, tempReg, chsReg, cg);
               srm->reclaimScratchRegister(chsReg);
               }
            else
               {
               generateRegImmInstruction(TR::InstOpCode::CMPRegImm4(), node, tempReg, (int32_t)chs, cg, TR_HEAP_SIZE_FOR_BARRIER_RANGE);
               }
            }

         generateLabelInstruction(TR::InstOpCode::JAE4, node, cardMarkDoneLabel, cg);
         }

      generateRegImmInstruction(TR::InstOpCode::SHRRegImm1(), node, tempReg, comp->getOptions()->getHeapAddressToCardAddressShift(), cg);

      // Mark the card
      //
      const uint8_t dirtyCard = 1;

      TR::MemoryReference *cardTableMR;

      if (comp->getOptions()->isVariableActiveCardTableBase())
         {
         TR::MemoryReference *actbMR =
            generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, activeCardTableBase), cg);
         generateRegMemInstruction(TR::InstOpCode::ADDRegMem(), node, tempReg, actbMR, cg);
         cardTableMR = generateX86MemoryReference(tempReg, 0, cg);
         }
      else
         {
         uintptr_t actb = comp->getOptions()->getActiveCardTableBase();

         if (comp->target().is64Bit() && (!IS_32BIT_SIGNED(actb) || TR::Compiler->om.nativeAddressesCanChangeSize()))
            {
            TR::Register *tempReg3 = srm->findOrCreateScratchRegister();
               generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, tempReg3, actb, cg, TR_ACTIVE_CARD_TABLE_BASE);
            cardTableMR = generateX86MemoryReference(tempReg3, tempReg, 0, cg);
            srm->reclaimScratchRegister(tempReg3);
            }
         else
            {
            cardTableMR = generateX86MemoryReference(NULL, tempReg, 0, (int32_t)actb, cg);
            cardTableMR->setReloKind(TR_ACTIVE_CARD_TABLE_BASE);
            }
         }

      generateMemImmInstruction(TR::InstOpCode::S1MemImm1, node, cardTableMR, dirtyCard, cg);

      srm->reclaimScratchRegister(tempReg);
      }

   if (doIsDestAHeapObjectCheck && doIsDestInOldSpaceCheck)
      {
      generateLabelInstruction(TR::InstOpCode::label, node, cardMarkDoneLabel, cg);
      }

   if (doSrcIsNullCheck)
      {
      generateRegRegInstruction(TR::InstOpCode::TESTRegReg(), node, srcReg, srcReg, cg);
      generateLabelInstruction(TR::InstOpCode::JE4, node, doneLabel, cg);
      }

   if (doIsDestInOldSpaceCheck)
      {
      static char *disableWrtbarOpt = feGetEnv("TR_DisableWrtbarOpt");

      TR::InstOpCode::Mnemonic branchOp;
      auto gcModeForSnippet = gcMode;

      bool skipSnippetIfSrcNotOld = false;
      bool skipSnippetIfDestOld = false;
      bool skipSnippetIfDestRemembered = false;

      TR::LabelSymbol *labelAfterBranchToSnippet = NULL;

      if (gcMode == gc_modron_wrtbar_always)
         {
         // Always call the write barrier helper.
         //
         // TODO: this should be an inline call.
         //
         branchOp = TR::InstOpCode::JMP4;
         }
      else if (doCheckConcurrentMarkActive)
         {
         //TR_ASSERT(wrtbarNode, "Must not be an arraycopy");

         // If the concurrent mark thread IS active then call the gencon write barrier in the helper
         // to perform card marking and any necessary remembered set updates.
         //
         // This is expected to be true for only a very small percentage of the time and hence
         // handling it out of line is justified.
         //
         if (!comp->getOption(TR_DisableWriteBarriersRangeCheck)
             && (node->getOpCodeValue() == TR::awrtbari)
             && doInternalControlFlow)
            {
            bool is64Bit = comp->target().is64Bit(); // On compressed refs, owningObjectReg is already uncompressed, and the vmthread fields are 64 bits
            labelAfterBranchToSnippet = generateLabelSymbol(cg);
            // AOT support to be implemented in another PR
            if (!comp->getOptions()->isVariableHeapSizeForBarrierRange0() && !comp->compileRelocatableCode() && !disableWrtbarOpt)
               {
               uintptr_t che = comp->getOptions()->getHeapBaseForBarrierRange0() + comp->getOptions()->getHeapSizeForBarrierRange0();
               if (comp->target().is64Bit() && !IS_32BIT_SIGNED(che))
                  {
                  generateRegMemInstruction(TR::InstOpCode::CMP8RegMem, node, owningObjectReg, generateX86MemoryReference(cg->findOrCreate8ByteConstant(node, che), cg), cg);
                  }
               else
                  {
                  generateRegImmInstruction(TR::InstOpCode::CMPRegImm4(), node, owningObjectReg, (int32_t)che, cg);
                  }
               }
            else
               {
               uintptr_t chb = comp->getOptions()->getHeapBaseForBarrierRange0();
               TR::Register *tempOwningObjReg = srm->findOrCreateScratchRegister();
               generateRegRegInstruction(TR::InstOpCode::MOVRegReg(),  node, tempOwningObjReg, owningObjectReg, cg);
               if (comp->target().is64Bit() && (!IS_32BIT_SIGNED(chb) || TR::Compiler->om.nativeAddressesCanChangeSize()))
                  {
                  TR::Register *chbReg = srm->findOrCreateScratchRegister();
                  generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, chbReg, chb, cg, TR_HEAP_BASE_FOR_BARRIER_RANGE);
                  generateRegRegInstruction(TR::InstOpCode::SUBRegReg(), node, tempOwningObjReg, chbReg, cg);
                  srm->reclaimScratchRegister(chbReg);
                  }
               else
                  {
                  generateRegImmInstruction(TR::InstOpCode::SUBRegImm4(), node, tempOwningObjReg, (int32_t)chb, cg, TR_HEAP_BASE_FOR_BARRIER_RANGE);
                  }
               TR::MemoryReference *vhsMR1 =
                     generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, heapSizeForBarrierRange0), cg);
               generateRegMemInstruction(TR::InstOpCode::CMPRegMem(), node, tempOwningObjReg, vhsMR1, cg);
               srm->reclaimScratchRegister(tempOwningObjReg);
               }

            generateLabelInstruction(TR::InstOpCode::JAE1, node, doneLabel, cg);

            skipSnippetIfSrcNotOld = true;
            }
         else
            {
            skipSnippetIfDestOld = true;
            }

         // See if we can do a TR::InstOpCode::TEST1MemImm1
         //
         int32_t byteOffset = byteOffsetForMask(J9_PRIVATE_FLAGS_CONCURRENT_MARK_ACTIVE, cg);
         if (byteOffset != -1)
            {
            TR::MemoryReference *vmThreadPrivateFlagsMR = generateX86MemoryReference(cg->getVMThreadRegister(), byteOffset + offsetof(J9VMThread, privateFlags), cg);
            generateMemImmInstruction(TR::InstOpCode::TEST1MemImm1, node, vmThreadPrivateFlagsMR, J9_PRIVATE_FLAGS_CONCURRENT_MARK_ACTIVE >> (8*byteOffset), cg);
            }
         else
            {
            TR::MemoryReference *vmThreadPrivateFlagsMR = generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, privateFlags), cg);
            generateMemImmInstruction(TR::InstOpCode::TEST4MemImm4, node, vmThreadPrivateFlagsMR, J9_PRIVATE_FLAGS_CONCURRENT_MARK_ACTIVE, cg);
            }

         generateWriteBarrierCall(TR::InstOpCode::JNE4, node, gc_modron_wrtbar_cardmark_and_oldcheck, owningObjectReg, srcReg, doneLabel, cg);

         // If the destination object is old and not remembered then process the remembered
         // set update out-of-line with the generational helper.
         //
         skipSnippetIfDestRemembered = true;
         gcModeForSnippet = gc_modron_wrtbar_oldcheck;
         }
      else if (gcMode == gc_modron_wrtbar_oldcheck)
         {
         // For pure generational barriers if the object is old and remembered then the helper
         // can be skipped.
         //
         skipSnippetIfDestOld = true;
         skipSnippetIfDestRemembered = true;
         }
      else
         {
         skipSnippetIfDestOld = true;
         skipSnippetIfDestRemembered = false;
         }

      if (skipSnippetIfSrcNotOld || skipSnippetIfDestOld)
         {
         TR_ASSERT((!skipSnippetIfSrcNotOld || !skipSnippetIfDestOld), "At most one of skipSnippetIfSrcNotOld and skipSnippetIfDestOld can be true");
         TR_ASSERT(skipSnippetIfDestOld || (srcReg != NULL), "Expected to have a source register for wrtbari");

         bool is64Bit = comp->target().is64Bit(); // On compressed refs, owningObjectReg is already uncompressed, and the vmthread fields are 64 bits
         bool checkDest = skipSnippetIfDestOld;   // Otherwise, check the src value
         bool skipSnippetIfOld = skipSnippetIfDestOld;   // Otherwise, skip if the checked value (source or destination) is not old
         labelAfterBranchToSnippet = generateLabelSymbol(cg);
         // AOT support to be implemented in another PR
         if (!comp->getOptions()->isVariableHeapSizeForBarrierRange0() && !comp->compileRelocatableCode() && !disableWrtbarOpt)
            {
            uintptr_t che = comp->getOptions()->getHeapBaseForBarrierRange0() + comp->getOptions()->getHeapSizeForBarrierRange0();
            if (comp->target().is64Bit() && !IS_32BIT_SIGNED(che))
               {
               generateRegMemInstruction(TR::InstOpCode::CMP8RegMem, node, checkDest ? owningObjectReg : srcReg, generateX86MemoryReference(cg->findOrCreate8ByteConstant(node, che), cg), cg);
               }
            else
               {
               generateRegImmInstruction(TR::InstOpCode::CMPRegImm4(), node, checkDest ? owningObjectReg : srcReg, (int32_t)che, cg);
               }
            }
         else
            {
            uintptr_t chb = comp->getOptions()->getHeapBaseForBarrierRange0();
            TR::Register *tempReg = srm->findOrCreateScratchRegister();
            generateRegRegInstruction(TR::InstOpCode::MOVRegReg(),  node, tempReg, checkDest ? owningObjectReg : srcReg, cg);
            if (comp->target().is64Bit() && (!IS_32BIT_SIGNED(chb) || TR::Compiler->om.nativeAddressesCanChangeSize()))
               {
               TR::Register *chbReg = srm->findOrCreateScratchRegister();
               generateRegImm64Instruction(TR::InstOpCode::MOV8RegImm64, node, chbReg, chb, cg, TR_HEAP_BASE_FOR_BARRIER_RANGE);
               generateRegRegInstruction(TR::InstOpCode::SUBRegReg(), node, tempReg, chbReg, cg);
               srm->reclaimScratchRegister(chbReg);
               }
            else
               {
               generateRegImmInstruction(TR::InstOpCode::SUBRegImm4(), node, tempReg, (int32_t)chb, cg, TR_HEAP_BASE_FOR_BARRIER_RANGE);
               }
            TR::MemoryReference *vhsMR1 =
                  generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, heapSizeForBarrierRange0), cg);
            generateRegMemInstruction(TR::InstOpCode::CMPRegMem(), node, tempReg, vhsMR1, cg);
            }

         branchOp = skipSnippetIfOld ? TR::InstOpCode::JB4 : TR::InstOpCode::JAE4;  // For branch to snippet
         TR::InstOpCode::Mnemonic reverseBranchOp = skipSnippetIfOld ? TR::InstOpCode::JAE4 : TR::InstOpCode::JB4;  // For branch past snippet

         // Now performing check for remembered
         if (skipSnippetIfDestRemembered)
            {
            // Set up for branch *past* snippet call for previous comparison
            generateLabelInstruction(reverseBranchOp, node, labelAfterBranchToSnippet, cg);

            int32_t byteOffset = byteOffsetForMask(J9_OBJECT_HEADER_REMEMBERED_MASK_FOR_TEST, cg);
            if (byteOffset != -1)
               {
               TR::MemoryReference *MR = generateX86MemoryReference(owningObjectReg, byteOffset + TR::Compiler->om.offsetOfHeaderFlags(), cg);
               generateMemImmInstruction(TR::InstOpCode::TEST1MemImm1, node, MR, J9_OBJECT_HEADER_REMEMBERED_MASK_FOR_TEST >> (8*byteOffset), cg);
               }
            else
               {
               TR::MemoryReference *MR = generateX86MemoryReference(owningObjectReg, TR::Compiler->om.offsetOfHeaderFlags(), cg);
               generateMemImmInstruction(TR::InstOpCode::TEST4MemImm4, node, MR, J9_OBJECT_HEADER_REMEMBERED_MASK_FOR_TEST, cg);
               }
            branchOp=TR::InstOpCode::JE4;
            }
         }

      generateWriteBarrierCall(branchOp, node, gcModeForSnippet, owningObjectReg, srcReg, doneLabel, cg);

      if (labelAfterBranchToSnippet)
         generateLabelInstruction(TR::InstOpCode::label, node, labelAfterBranchToSnippet, cg);
      }

   int32_t numPostConditions = 2 + srm->numAvailableRegisters();

   if (srcReg)
      {
      numPostConditions++;
      }

   TR::RegisterDependencyConditions *conditions =
      generateRegisterDependencyConditions((uint8_t) 0, numPostConditions, cg);

   conditions->addPostCondition(owningObjectReg, TR::RealRegister::NoReg, cg);
   if (srcReg)
      {
      conditions->addPostCondition(srcReg, TR::RealRegister::NoReg, cg);
      }

   conditions->addPostCondition(cg->getVMThreadRegister(), TR::RealRegister::ebp, cg);

   srm->addScratchRegistersToDependencyList(conditions);
   conditions->stopAddingConditions();

   generateLabelInstruction(TR::InstOpCode::label, node, doneLabel, conditions, cg);

   srm->stopUsingRegisters();
   }


static TR::Instruction *
doReferenceStore(
   TR::Node               *node,
   TR::MemoryReference *storeMR,
   TR::Register           *sourceReg,
   bool                   usingCompressedPointers,
   TR::CodeGenerator      *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR::InstOpCode::Mnemonic storeOp = usingCompressedPointers ? TR::InstOpCode::S4MemReg : TR::InstOpCode::SMemReg();
   TR::Instruction *instr = generateMemRegInstruction(storeOp, node, storeMR, sourceReg, cg);

   // for real-time GC, the data reference has already been resolved into an earlier LEA instruction so this padding isn't needed
   //   even if the node symbol is marked as unresolved (the store instruction above is storing through a register
   //   that contains the resolved address)
   if (!comp->getOptions()->realTimeGC() && node->getSymbolReference()->isUnresolved())
      {
      TR::TreeEvaluator::padUnresolvedDataReferences(node, *node->getSymbolReference(), cg);
      }

   return instr;
   }


void J9::X86::TreeEvaluator::VMwrtbarWithStoreEvaluator(
   TR::Node                   *node,
   TR::MemoryReference *storeMR,
   TR_X86ScratchRegisterManager *scratchRegisterManager,
   TR::Node                   *destOwningObject,
   TR::Node                   *sourceObject,
   bool                       isImplicitExceptionPoint,
   TR::CodeGenerator          *cg,
   bool                       nullAdjusted)
   {
   TR_ASSERT(storeMR, "assertion failure");

   TR::Compilation *comp = cg->comp();

   TR::Register *owningObjectRegister = cg->evaluate(destOwningObject);
   TR::Register *sourceRegister = cg->evaluate(sourceObject);

   auto gcMode = TR::Compiler->om.writeBarrierType();
   bool isRealTimeGC = (comp->getOptions()->realTimeGC())? true:false;

   bool usingCompressedPointers = false;
   bool usingLowMemHeap = false;
   bool useShiftedOffsets = (TR::Compiler->om.compressedReferenceShiftOffset() != 0);
   TR::Node *translatedStore = NULL;

   // NOTE:
   //
   // If you change this code you also need to change writeBarrierEvaluator() in TreeEvaluator.cpp
   //
   if (comp->useCompressedPointers() &&
       ((node->getOpCode().isCheck() && node->getFirstChild()->getOpCode().isIndirect() &&
        (node->getFirstChild()->getSecondChild()->getDataType() != TR::Address)) ||
        (node->getOpCode().isIndirect() && (node->getSecondChild()->getDataType() != TR::Address))))
      {
      if (node->getOpCode().isCheck())
         translatedStore = node->getFirstChild();
      else
         translatedStore = node;

      usingLowMemHeap = true;
      usingCompressedPointers = true;
      }

   TR::Register *translatedSourceReg = sourceRegister;
   if (usingCompressedPointers && (!usingLowMemHeap || useShiftedOffsets))
      {
      // handle stores of null values here

      if (nullAdjusted)
         translatedSourceReg = translatedStore->getSecondChild()->getRegister();
      else
         {
         translatedSourceReg = cg->evaluate(translatedStore->getSecondChild());
         if (!usingLowMemHeap)
            {
            generateRegRegInstruction(TR::InstOpCode::TESTRegReg(), translatedStore, sourceRegister, sourceRegister, cg);
            generateRegRegInstruction(TR::InstOpCode::CMOVERegReg(), translatedStore, translatedSourceReg, sourceRegister, cg);
            }
         }
      }

   TR::Instruction *storeInstr = NULL;
   TR::Register *storeAddressRegForRealTime = NULL;

   if (isRealTimeGC)
      {
      // Realtime GC evaluates storeMR into a register here and then uses it to do the store after the write barrier

      // If reference is unresolved, need to resolve it right here before the barrier starts
      // Otherwise, we could get stopped during the resolution and that could invalidate any tests we would have performend
      //   beforehand
      // For simplicity, just evaluate the store address into storeAddressRegForRealTime right now
      storeAddressRegForRealTime = scratchRegisterManager->findOrCreateScratchRegister();
      generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, storeAddressRegForRealTime, storeMR, cg);
      if (node->getSymbolReference()->isUnresolved())
         {
         TR::TreeEvaluator::padUnresolvedDataReferences(node, *node->getSymbolReference(), cg);

         // storeMR was created against a (i)wrtbar node which is a store.  The unresolved data snippet that
         //  was created set the checkVolatility bit based on that node being a store.  Since the resolution
         //  is now going to occur on a LEA instruction, which does not require any memory fence and hence
         //  no volatility check, we need to clear that "store" ness of the unresolved data snippet
         TR::UnresolvedDataSnippet *snippet = storeMR->getUnresolvedDataSnippet();
         if (snippet)
            snippet->resetUnresolvedStore();
         }
      }
   else
      {
      // Non-realtime does the store first, then the write barrier.
      //
      storeInstr = doReferenceStore(node, storeMR, translatedSourceReg, usingCompressedPointers, cg);
      }

   if (TR::Compiler->om.writeBarrierType() == gc_modron_wrtbar_always && !isRealTimeGC)
      {
      TR::RegisterDependencyConditions *deps = NULL;
      TR::LabelSymbol *doneWrtBarLabel = generateLabelSymbol(cg);

      if (comp->target().is32Bit() && sourceObject->isNonNull() == false)
         {
         TR::LabelSymbol *startLabel = generateLabelSymbol(cg);
         startLabel->setStartInternalControlFlow();
         doneWrtBarLabel->setEndInternalControlFlow();

         generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);
         generateRegRegInstruction(TR::InstOpCode::TESTRegReg(), node, sourceRegister, sourceRegister, cg);
         generateLabelInstruction(TR::InstOpCode::JE4, node, doneWrtBarLabel, cg);

         deps = generateRegisterDependencyConditions(0, 3, cg);
         deps->addPostCondition(sourceRegister, TR::RealRegister::NoReg, cg);
         deps->addPostCondition(owningObjectRegister, TR::RealRegister::NoReg, cg);
         deps->addPostCondition(cg->getVMThreadRegister(), TR::RealRegister::ebp, cg);
         deps->stopAddingConditions();
         }

      generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, floatTemp1), cg), owningObjectRegister, cg);
      generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, generateX86MemoryReference(cg->getVMThreadRegister(), offsetof(J9VMThread, floatTemp2), cg), sourceRegister, cg);

      TR::SymbolReference* wrtBarSymRef = comp->getSymRefTab()->findOrCreateWriteBarrierStoreSymbolRef();
      generateImmSymInstruction(TR::InstOpCode::CALLImm4, node, (uintptr_t)wrtBarSymRef->getMethodAddress(), wrtBarSymRef, cg);

      generateLabelInstruction(TR::InstOpCode::label, node, doneWrtBarLabel, deps, cg);
      }
   else
      {
      if (isRealTimeGC)
         {
         TR::TreeEvaluator::VMwrtbarRealTimeWithoutStoreEvaluator(
                  node,
                  storeMR,
                  storeAddressRegForRealTime,
                  destOwningObject,
                  sourceObject,
                  NULL,
                  scratchRegisterManager,
                  cg);
         }
      else
         {
         TR::TreeEvaluator::VMwrtbarWithoutStoreEvaluator(
            node,
            destOwningObject,
            sourceObject,
            NULL,
            scratchRegisterManager,
            cg);
         }
      }

   // Realtime GCs must do the write barrier first and then the store.
   //
   if (isRealTimeGC)
      {
      TR_ASSERT(storeAddressRegForRealTime, "assertion failure");
      TR::MemoryReference *myStoreMR = generateX86MemoryReference(storeAddressRegForRealTime, 0, cg);
      storeInstr = doReferenceStore(node, myStoreMR, translatedSourceReg, usingCompressedPointers, cg);
      scratchRegisterManager->reclaimScratchRegister(storeAddressRegForRealTime);
      }

   if (!usingLowMemHeap || useShiftedOffsets)
      cg->decReferenceCount(sourceObject);

   cg->decReferenceCount(destOwningObject);
   storeMR->decNodeReferenceCounts(cg);

   if (isImplicitExceptionPoint)
      cg->setImplicitExceptionPoint(storeInstr);
   }


void J9::X86::TreeEvaluator::generateVFTMaskInstruction(TR::Node *node, TR::Register *reg, TR::CodeGenerator *cg)
   {
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());
   uintptr_t mask = TR::Compiler->om.maskOfObjectVftField();
   bool is64Bit = cg->comp()->target().is64Bit(); // even with compressed object headers, a 64-bit mask operation is safe, though it may waste 1 byte because of the rex prefix
   if (~mask == 0)
      {
      // no mask instruction required
      }
   else if (~mask <= 127)
      {
      generateRegImmInstruction(TR::InstOpCode::ANDRegImms(is64Bit), node, reg, TR::Compiler->om.maskOfObjectVftField(), cg);
      }
   else
      {
      generateRegImmInstruction(TR::InstOpCode::ANDRegImm4(is64Bit), node, reg, TR::Compiler->om.maskOfObjectVftField(), cg);
      }
   }


void
VMgenerateCatchBlockBBStartPrologue(
      TR::Node *node,
      TR::Instruction *fenceInstruction,
      TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());

   if (comp->getJittedMethodSymbol()->usesSinglePrecisionMode() &&
       cg->enableSinglePrecisionMethods())
      {
      cg->setLastCatchAppendInstruction(fenceInstruction);
      }

   TR::Block *block = node->getBlock();
   if (fej9->shouldPerformEDO(block, comp))
      {
      TR_ASSERT_FATAL(cg->comp()->getRecompilationInfo(), "Recompilation info should be available");

      TR::LabelSymbol *snippetLabel = generateLabelSymbol(cg);
      TR::LabelSymbol *restartLabel = generateLabelSymbol(cg);

      generateMemInstruction(TR::InstOpCode::DEC4Mem, node, generateX86MemoryReference(comp->getRecompilationInfo()->getCounterSymRef(), cg), cg);
      generateLabelInstruction(TR::InstOpCode::JE4, node, snippetLabel, cg);
      generateLabelInstruction(TR::InstOpCode::label, node, restartLabel, cg);
      cg->addSnippet(new (cg->trHeapMemory()) TR::X86ForceRecompilationSnippet(cg, node, restartLabel, snippetLabel));
      cg->comp()->getRecompilationInfo()->getJittedBodyInfo()->setHasEdoSnippet();
      }

   }


TR::Register *
J9::X86::TreeEvaluator::tstartEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   /*
      xbegin fall_back_path
      mov monReg, [obj+Lw_offset]
      cmp monReg, 0;
      je fallThroughLabel
      cmp monReg, rbp
      je fallThroughLabel
      xabort
   fall_back_path:
      test eax, 0x2
      jne gotoTransientFailureNodeLabel
      test eax, 0x00000001
      je persistentFailureLabel
      test eax, 0x01000000
      jne gotoTransientFailureNodeLabel
      jmp persistentFailLabel
   gotoTransientFailureNodeLabel:
      mov counterReg,100
   spinLabel:
      dec counterReg
      jne spinLabel
      jmp TransientFailureNodeLabel
   */
   TR::Compilation *comp = cg->comp();
   TR::Node *persistentFailureNode = node->getFirstChild();
   TR::Node *transientFailureNode  = node->getSecondChild();
   TR::Node *fallThroughNode = node->getThirdChild();
   TR::Node *objNode = node->getChild(3);
   TR::Node *GRANode = NULL;

   TR::LabelSymbol *startLabel = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   startLabel->setStartInternalControlFlow();
   TR::LabelSymbol *endLabel = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   endLabel->setEndInternalControlFlow();

   TR::LabelSymbol *gotoTransientFailure = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   TR::LabelSymbol *gotoPersistentFailure = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   TR::LabelSymbol *gotoFallThrough = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   TR::LabelSymbol *transientFailureLabel  = transientFailureNode->getBranchDestination()->getNode()->getLabel();
   TR::LabelSymbol *persistentFailureLabel = persistentFailureNode->getBranchDestination()->getNode()->getLabel();
   TR::LabelSymbol *fallBackPathLabel = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   TR::LabelSymbol *fallThroughLabel = fallThroughNode->getBranchDestination()->getNode()->getLabel();

   TR::Register *objReg = cg->evaluate(objNode);
   TR::Register *accReg = cg->allocateRegister();
   TR::Register *monReg = cg->allocateRegister();
   TR::RegisterDependencyConditions *fallBackConditions = generateRegisterDependencyConditions((uint8_t)0, 2, cg);
   TR::RegisterDependencyConditions *endLabelConditions;
   TR::RegisterDependencyConditions *fallThroughConditions = NULL;
   TR::RegisterDependencyConditions *persistentConditions = NULL;
   TR::RegisterDependencyConditions *transientConditions = NULL;

   if (fallThroughNode->getNumChildren() != 0)
      {
      GRANode = fallThroughNode->getFirstChild();
      cg->evaluate(GRANode);
      List<TR::Register> popRegisters(cg->trMemory());
      fallThroughConditions = generateRegisterDependencyConditions(GRANode, cg, 0, &popRegisters);
      cg->decReferenceCount(GRANode);
      }

   if (persistentFailureNode->getNumChildren() != 0)
      {
      GRANode = persistentFailureNode->getFirstChild();
      cg->evaluate(GRANode);
      List<TR::Register> popRegisters(cg->trMemory());
      persistentConditions = generateRegisterDependencyConditions(GRANode, cg, 0, &popRegisters);
      cg->decReferenceCount(GRANode);
      }

   if (transientFailureNode->getNumChildren() != 0)
      {
      GRANode = transientFailureNode->getFirstChild();
      cg->evaluate(GRANode);
      List<TR::Register> popRegisters(cg->trMemory());
      transientConditions = generateRegisterDependencyConditions(GRANode, cg, 0, &popRegisters);
      cg->decReferenceCount(GRANode);
      }

   //startLabel
   //add place holder register so that eax would not contain any useful value before xbegin
   TR::Register *dummyReg = cg->allocateRegister();
   dummyReg->setPlaceholderReg();
   TR::RegisterDependencyConditions *startLabelConditions = generateRegisterDependencyConditions((uint8_t)0, 1, cg);
   startLabelConditions->addPostCondition(dummyReg, TR::RealRegister::eax, cg);
   startLabelConditions->stopAddingConditions();
   cg->stopUsingRegister(dummyReg);
   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, startLabelConditions, cg);

   //xbegin fall_back_path
   generateLongLabelInstruction(TR::InstOpCode::XBEGIN4, node, fallBackPathLabel, cg);
   //mov monReg, obj+offset
   int32_t lwOffset = cg->fej9()->getByteOffsetToLockword((TR_OpaqueClassBlock *) cg->getMonClass(node));
   TR::MemoryReference *objLockRef = generateX86MemoryReference(objReg, lwOffset, cg);
   if (comp->target().is64Bit() && cg->fej9()->generateCompressedLockWord())
      {
      generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, monReg, objLockRef, cg);
      }
   else
      {
      generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, monReg, objLockRef, cg);
      }

   if (comp->target().is64Bit() && cg->fej9()->generateCompressedLockWord())
      {
      generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, monReg, 0, cg);
      }
   else
      {
      generateRegImmInstruction(TR::InstOpCode::CMPRegImm4(), node, monReg, 0, cg);
      }

   if (fallThroughConditions)
      generateLabelInstruction(TR::InstOpCode::JE4, node, fallThroughLabel, fallThroughConditions, cg);
   else
      generateLabelInstruction(TR::InstOpCode::JE4, node, fallThroughLabel, cg);

   TR::Register *vmThreadReg = cg->getVMThreadRegister();
   if (comp->target().is64Bit() && cg->fej9()->generateCompressedLockWord())
      {
      generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, monReg, vmThreadReg, cg);
      }
   else
      {
      generateRegRegInstruction(TR::InstOpCode::CMPRegReg(), node, monReg, vmThreadReg, cg);
      }

   if (fallThroughConditions)
      generateLabelInstruction(TR::InstOpCode::JE4, node, fallThroughLabel, fallThroughConditions, cg);
   else
      generateLabelInstruction(TR::InstOpCode::JE4, node, fallThroughLabel, cg);

   //xabort
   generateImmInstruction(TR::InstOpCode::XABORT, node, 0x01, cg);

   cg->stopUsingRegister(monReg);
   //fall_back_path:
   generateLabelInstruction(TR::InstOpCode::label, node, fallBackPathLabel, cg);

   endLabelConditions = generateRegisterDependencyConditions((uint8_t)0, 1, cg);
   endLabelConditions->addPostCondition(accReg, TR::RealRegister::eax, cg);
   endLabelConditions->stopAddingConditions();

   // test eax, 0x2
   generateRegImmInstruction(TR::InstOpCode::TEST1AccImm1, node, accReg, 0x2, cg);
   generateLabelInstruction(TR::InstOpCode::JNE4, node, gotoTransientFailure, cg);

   // abort because of nonzero lockword is also transient failure
   generateRegImmInstruction(TR::InstOpCode::TEST4AccImm4, node, accReg, 0x00000001, cg);
   if (persistentConditions)
      generateLabelInstruction(TR::InstOpCode::JE4, node, persistentFailureLabel, persistentConditions, cg);
   else
      generateLabelInstruction(TR::InstOpCode::JE4, node, persistentFailureLabel, cg);

   generateRegImmInstruction(TR::InstOpCode::TEST4AccImm4, node, accReg, 0x01000000, cg);
   // je gotransientFailureNodeLabel
   generateLabelInstruction(TR::InstOpCode::JNE4, node, gotoTransientFailure, cg);

   if (persistentConditions)
      generateLabelInstruction(TR::InstOpCode::JMP4, node, persistentFailureLabel, persistentConditions, cg);
   else
      generateLabelInstruction(TR::InstOpCode::JMP4, node, persistentFailureLabel, cg);
   cg->stopUsingRegister(accReg);

   // gotoTransientFailureLabel:
   if (transientConditions)
      generateLabelInstruction(TR::InstOpCode::label, node, gotoTransientFailure, transientConditions, cg);
   else
      generateLabelInstruction(TR::InstOpCode::label, node, gotoTransientFailure, cg);

   //delay
   TR::Register *counterReg = cg->allocateRegister();
   generateRegImmInstruction(TR::InstOpCode::MOV4RegImm4, node, counterReg, 100, cg);
   TR::LabelSymbol *spinLabel = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   generateLabelInstruction(TR::InstOpCode::label, node, spinLabel, cg);
   generateInstruction(TR::InstOpCode::PAUSE, node, cg);
   generateInstruction(TR::InstOpCode::PAUSE, node, cg);
   generateInstruction(TR::InstOpCode::PAUSE, node, cg);
   generateInstruction(TR::InstOpCode::PAUSE, node, cg);
   generateInstruction(TR::InstOpCode::PAUSE, node, cg);
   generateRegInstruction(TR::InstOpCode::DEC4Reg, node, counterReg, cg);
   TR::RegisterDependencyConditions *loopConditions = generateRegisterDependencyConditions((uint8_t)0, 1, cg);
   loopConditions->addPostCondition(counterReg, TR::RealRegister::NoReg, cg);
   loopConditions->stopAddingConditions();
   generateLabelInstruction(TR::InstOpCode::JNE4, node, spinLabel, loopConditions, cg);
   cg->stopUsingRegister(counterReg);

   if(transientConditions)
      generateLabelInstruction(TR::InstOpCode::JMP4, node, transientFailureLabel, transientConditions, cg);
   else
      generateLabelInstruction(TR::InstOpCode::JMP4, node, transientFailureLabel, cg);

   generateLabelInstruction(TR::InstOpCode::label, node, endLabel, endLabelConditions, cg);
   cg->decReferenceCount(objNode);
   cg->decReferenceCount(persistentFailureNode);
   cg->decReferenceCount(transientFailureNode);
   return NULL;
   }

TR::Register *
J9::X86::TreeEvaluator::tfinishEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   generateInstruction(TR::InstOpCode::XEND, node, cg);
   return NULL;
   }

TR::Register *
J9::X86::TreeEvaluator::tabortEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   generateImmInstruction(TR::InstOpCode::XABORT, node, 0x04, cg);
   return NULL;
   }

TR::Register *
J9::X86::TreeEvaluator::directCallEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   static bool useJapaneseCompression = (feGetEnv("TR_JapaneseComp") != NULL);
   TR::Compilation *comp = cg->comp();
   TR::SymbolReference *symRef = node->getSymbolReference();

   bool callInlined = false;
   TR::Register *returnRegister = NULL;
   TR::MethodSymbol *symbol = node->getSymbol()->castToMethodSymbol();

#ifdef J9VM_OPT_JAVA_CRYPTO_ACCELERATION
   if (cg->inlineCryptoMethod(node, returnRegister))
      {
      return returnRegister;
      }
#endif

   if (symbol->isHelper())
      {
      switch (symRef->getReferenceNumber())
         {
         case TR_checkAssignable:
            return TR::TreeEvaluator::checkcastinstanceofEvaluator(node, cg);
         default:
            break;
         }
      }

   switch (symbol->getMandatoryRecognizedMethod())
      {
      case TR::java_lang_StringLatin1_indexOfChar:
      case TR::com_ibm_jit_JITHelpers_intrinsicIndexOfLatin1:
         if (cg->getSupportsInlineStringIndexOf())
            return inlineIntrinsicIndexOf(node, cg, true);
         break;

      case TR::java_lang_StringUTF16_indexOfCharUnsafe:
      case TR::com_ibm_jit_JITHelpers_intrinsicIndexOfUTF16:
         if (cg->getSupportsInlineStringIndexOf())
            return inlineIntrinsicIndexOf(node, cg, false);
         break;

      case TR::java_lang_StringLatin1_indexOf:
      case TR::com_ibm_jit_JITHelpers_intrinsicIndexOfStringLatin1:
         if (cg->getSupportsInlineStringIndexOfString())
            returnRegister = inlineIntrinsicStringIndexOfString(node, cg, true);

         callInlined = (returnRegister != NULL);
         break;

      case TR::java_lang_StringUTF16_indexOf:
      case TR::java_lang_StringUTF16_indexOfUnsafe:
      case TR::com_ibm_jit_JITHelpers_intrinsicIndexOfStringUTF16:
         if (cg->getSupportsInlineStringIndexOfString())
            returnRegister = inlineIntrinsicStringIndexOfString(node, cg, false);

         callInlined = (returnRegister != NULL);
         break;

      case TR::com_ibm_jit_JITHelpers_transformedEncodeUTF16Big:
      case TR::com_ibm_jit_JITHelpers_transformedEncodeUTF16Little:
         return TR::TreeEvaluator::encodeUTF16Evaluator(node, cg);

      case TR::java_lang_String_hashCodeImplDecompressed:
         if (cg->getSupportsInlineStringHashCode())
            returnRegister = inlineStringHashCode(node, false, cg);

         callInlined = (returnRegister != NULL);
         break;

      case TR::java_lang_String_hashCodeImplCompressed:
         if (cg->getSupportsInlineStringHashCode())
            returnRegister = inlineStringHashCode(node, true, cg);

         callInlined = (returnRegister != NULL);
         break;

      default:
         break;
      }

   if (cg->getSupportsInlineStringCaseConversion())
      {
      switch (symbol->getRecognizedMethod())
         {
         case TR::com_ibm_jit_JITHelpers_toUpperIntrinsicUTF16:
            return TR::TreeEvaluator::toUpperIntrinsicUTF16Evaluator(node, cg);
         case TR::com_ibm_jit_JITHelpers_toUpperIntrinsicLatin1:
            return TR::TreeEvaluator::toUpperIntrinsicLatin1Evaluator(node, cg);
         case TR::com_ibm_jit_JITHelpers_toLowerIntrinsicUTF16:
            return TR::TreeEvaluator::toLowerIntrinsicUTF16Evaluator(node, cg);
         case TR::com_ibm_jit_JITHelpers_toLowerIntrinsicLatin1:
            return TR::TreeEvaluator::toLowerIntrinsicLatin1Evaluator(node, cg);
         default:
            break;
         }
      }

   switch (symbol->getRecognizedMethod())
      {
      case TR::java_lang_Thread_onSpinWait:
         {
         static char *disableOSW = feGetEnv("TR_noPauseOnSpinWait");
         if (!disableOSW)
            {
            generateInstruction(TR::InstOpCode::PAUSE, node, cg);

            static char *printIt = feGetEnv("TR_showPauseOnSpinWait");
            if (printIt && comp->getOption(TR_TraceCG))
               {
               traceMsg(comp, "insert PAUSE for onSpinWait : node=%p, %s\n", node, comp->signature());
               }

            return NULL;
            }
         else
            break;
         }
#if JAVA_SPEC_VERSION < 19
      case TR::java_lang_StringCoding_hasNegatives:
#endif /* JAVA_SPEC_VERSION < 19 */
      case TR::java_lang_StringCoding_countPositives:
         {
         if (cg->comp()->target().is64Bit() && !TR::Compiler->om.canGenerateArraylets())
            {
            return inlineHasNegativesOrCountPositives(node, symbol->getRecognizedMethod(), cg);
            }
         }
         break;
      case TR::java_nio_Bits_keepAlive:
      case TR::java_lang_ref_Reference_reachabilityFence:
         {
         TR_ASSERT(node->getNumChildren() == 1, "keepAlive is assumed to have just one argument");

         // The only purpose of keepAlive is to prevent an otherwise
         // unreachable object from being garbage collected, because we don't
         // want its finalizer to be called too early.  There's no need to
         // generate a full-blown call site just for this purpose.

         TR::Register *valueToKeepAlive = cg->evaluate(node->getFirstChild());

         // In theory, a value could be kept alive on the stack, rather than in
         // a register.  It is unfortunate that the following deps will force
         // the value into a register for no reason.  However, in many common
         // cases, this label will have no effect on the generated code, and
         // will only affect GC maps.
         //
         TR::RegisterDependencyConditions *deps = generateRegisterDependencyConditions((uint8_t)1, (uint8_t)1, cg);
         deps->addPreCondition  (valueToKeepAlive, TR::RealRegister::NoReg, cg);
         deps->addPostCondition (valueToKeepAlive, TR::RealRegister::NoReg, cg);
         new (cg->trHeapMemory()) TR::X86LabelInstruction(TR::InstOpCode::label, node, generateLabelSymbol(cg), deps, cg);
         cg->decReferenceCount(node->getFirstChild());

         return NULL; // keepAlive has no return value
         }

      case TR::java_math_BigDecimal_noLLOverflowAdd:
      case TR::java_math_BigDecimal_noLLOverflowMul:
         if (cg->getSupportsBDLLHardwareOverflowCheck())
            {
            // Eat this call as its only here to anchor where a long lookaside overflow check
            // needs to be done.  There should be a TR::icmpeq node following
            // this one where the real overflow check will be inserted.
            //
            cg->recursivelyDecReferenceCount(node->getFirstChild());
            cg->recursivelyDecReferenceCount(node->getSecondChild());
            cg->evaluate(node->getChild(2));
            cg->decReferenceCount(node->getChild(2));
            returnRegister = cg->allocateRegister();
            node->setRegister(returnRegister);
            return returnRegister;
            }

         break;
      case TR::java_lang_StringLatin1_inflate_BICII:
         if (cg->getSupportsInlineStringLatin1Inflate())
            {
            return TR::TreeEvaluator::inlineStringLatin1Inflate(node, cg);
            }
         break;
      case TR::java_lang_Math_fma_F:
      case TR::java_lang_Math_fma_D:
      case TR::java_lang_StrictMath_fma_F:
      case TR::java_lang_StrictMath_fma_D:
         {
         static bool disableInlineFMA = feGetEnv("TR_DisableInlineFMA") != NULL;

         if (!disableInlineFMA && cg->comp()->target().cpu.supportsFeature(OMR_FEATURE_X86_FMA))
            return inlineMathFma(node, cg);

         break;
         }
      case TR::jdk_internal_util_ArraysSupport_vectorizedHashCode:
         {
         if (cg->getSupportsInlineVectorizedHashCode())
            {
            TR::Register *result = inlineVectorizedHashCode(node, cg);
            if (result)
               return result;
            }
         }
      case TR::java_lang_Math_sqrt:
      case TR::java_lang_StrictMath_sqrt:
      case TR::java_lang_System_nanoTime:
      case TR::sun_nio_ch_NativeThread_current:
         if (TR::TreeEvaluator::VMinlineCallEvaluator(node, false, cg))
            {
            returnRegister = node->getRegister();
            }
         else
            {
            returnRegister = TR::TreeEvaluator::performCall(node, false, true, cg);
            }

         callInlined = true;
         break;

      default:
         break;
      }


   // If the method to be called is marked as an inline method, see if it can
   // actually be generated inline.
   //
   if (!callInlined && (symbol->isVMInternalNative() || symbol->isJITInternalNative()))
      {
      if (TR::TreeEvaluator::VMinlineCallEvaluator(node, false, cg))
         return node->getRegister();
      else
         return TR::TreeEvaluator::performCall(node, false, true, cg);
      }
   else if (callInlined)
      {
      return returnRegister;
      }

   // Call was not inlined.  Delegate to the parent directCallEvaluator.
   //
   return J9::TreeEvaluator::directCallEvaluator(node, cg);
   }

TR::Register *
J9::X86::TreeEvaluator::inlineStringLatin1Inflate(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR_ASSERT_FATAL(cg->comp()->target().is64Bit(), "StringLatin1.inflate only supported on 64-bit targets");
   TR_ASSERT_FATAL(cg->getSupportsInlineStringLatin1Inflate(), "Inlining of StringLatin1.inflate not supported");
   TR_ASSERT_FATAL(!TR::Compiler->om.canGenerateArraylets(), "StringLatin1.inflate intrinsic is not supported with arraylets");
   TR_ASSERT_FATAL_WITH_NODE(node, node->getNumChildren() == 5, "Wrong number of children in inlineStringLatin1Inflate");

   intptr_t headerOffsetConst = TR::Compiler->om.contiguousArrayHeaderSizeInBytes();
   uint8_t vectorLengthConst = 16;

   TR::Register *srcBufferReg = cg->evaluate(node->getChild(0));
   TR::Register *srcOffsetReg = cg->gprClobberEvaluate(node->getChild(1), TR::InstOpCode::MOV4RegReg);
   TR::Register *destBufferReg = cg->evaluate(node->getChild(2));
   TR::Register *destOffsetReg = cg->gprClobberEvaluate(node->getChild(3), TR::InstOpCode::MOV4RegReg);
   TR::Register *lengthReg = cg->gprClobberEvaluate(node->getChild(4), TR::InstOpCode::MOV4RegReg);

   TR::Register *xmmHighReg = cg->allocateRegister(TR_VRF);
   TR::Register *xmmLowReg = cg->allocateRegister(TR_VRF);
   TR::Register *zeroReg = cg->allocateRegister(TR_VRF);
   TR::Register *scratchReg = cg->allocateRegister(TR_GPR);

   int maxDepCount = 10;
   TR::RegisterDependencyConditions *deps = generateRegisterDependencyConditions(0, maxDepCount, cg);
   deps->addPostCondition(xmmHighReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(xmmLowReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(zeroReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(lengthReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(srcBufferReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(destBufferReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(scratchReg, TR::RealRegister::eax, cg);
   deps->addPostCondition(srcOffsetReg, TR::RealRegister::ecx, cg);
   deps->addPostCondition(destOffsetReg, TR::RealRegister::edx, cg);

   TR::LabelSymbol *doneLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *copyResidueLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *afterCopy8Label = generateLabelSymbol(cg);

   TR::LabelSymbol *startLabel = generateLabelSymbol(cg);
   startLabel->setStartInternalControlFlow();
   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

   TR::Node *destOffsetNode = node->getChild(3);

   if (!destOffsetNode->isConstZeroValue())
      {
      // dest offset measured in characters, convert it to bytes
      generateRegRegInstruction(TR::InstOpCode::ADD4RegReg, node, destOffsetReg, destOffsetReg, cg);
      }

   generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, lengthReg, lengthReg, cg);
   generateLabelInstruction(TR::InstOpCode::JE4, node, doneLabel, cg);

   generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, lengthReg, 8, cg);
   generateLabelInstruction(TR::InstOpCode::JL4, node, afterCopy8Label, cg);

   // make sure the register is zero before interleaving
   generateRegRegInstruction(TR::InstOpCode::PXORRegReg, node, zeroReg, zeroReg, cg);

   TR::LabelSymbol *startLoop = generateLabelSymbol(cg);
   TR::LabelSymbol *endLoop = generateLabelSymbol(cg);

   // vectorized add in loop, 16 bytes per iteration
   // use srcOffsetReg for loop counter, add starting offset to lengthReg, subtract 16 (xmm register size)
   // to prevent reading/writing beyond the end of the array
   generateRegMemInstruction(TR::InstOpCode::LEA4RegMem, node, scratchReg, generateX86MemoryReference(lengthReg, srcOffsetReg, 0, -vectorLengthConst, cg), cg);

   generateLabelInstruction(TR::InstOpCode::label, node, startLoop, cg);
   generateRegRegInstruction(TR::InstOpCode::CMP4RegReg, node, srcOffsetReg, scratchReg, cg);
   generateLabelInstruction(TR::InstOpCode::JG4, node, endLoop, cg);

   generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, xmmHighReg, generateX86MemoryReference(srcBufferReg, srcOffsetReg, 0, headerOffsetConst, cg), cg);

   generateRegRegInstruction(TR::InstOpCode::MOVDQURegReg, node, xmmLowReg, xmmHighReg, cg);
   generateRegRegInstruction(TR::InstOpCode::PUNPCKHBWRegReg, node, xmmLowReg, zeroReg, cg);
   generateMemRegInstruction(TR::InstOpCode::MOVDQUMemReg, node, generateX86MemoryReference(destBufferReg, destOffsetReg, 0, headerOffsetConst + vectorLengthConst, cg), xmmLowReg, cg);

   generateRegRegInstruction(TR::InstOpCode::PUNPCKLBWRegReg, node, xmmHighReg, zeroReg, cg);
   generateMemRegInstruction(TR::InstOpCode::MOVDQUMemReg, node, generateX86MemoryReference(destBufferReg, destOffsetReg, 0, headerOffsetConst, cg), xmmHighReg, cg);

   // increase src offset by size of imm register
   // increase dest offset by double, to account for the byte->char inflation
   generateRegImmInstruction(TR::InstOpCode::ADD4RegImm4, node, srcOffsetReg, vectorLengthConst, cg);
   generateRegImmInstruction(TR::InstOpCode::ADD4RegImm4, node, destOffsetReg, 2 * vectorLengthConst, cg);

   // LOOP BACK
   generateLabelInstruction(TR::InstOpCode::JMP4, node, startLoop, cg);
   generateLabelInstruction(TR::InstOpCode::label, node, endLoop, cg);

   // AND length with 15 to compute residual remainder
   // then copy and interleave 8 bytes from src buffer with 0s into dest buffer if possible
   generateRegImmInstruction(TR::InstOpCode::AND4RegImm4, node, lengthReg, vectorLengthConst - 1, cg);

   generateRegImmInstruction(TR::InstOpCode::CMP4RegImm4, node, lengthReg, 8, cg);
   generateLabelInstruction(TR::InstOpCode::JL1, node, afterCopy8Label, cg);

   generateRegMemInstruction(TR::InstOpCode::MOVQRegMem, node, xmmLowReg, generateX86MemoryReference(srcBufferReg, srcOffsetReg, 0, headerOffsetConst, cg), cg);
   generateRegRegInstruction(TR::InstOpCode::PUNPCKLBWRegReg, node, xmmLowReg, zeroReg, cg);
   generateMemRegInstruction(TR::InstOpCode::MOVDQUMemReg, node, generateX86MemoryReference(destBufferReg, destOffsetReg, 0, headerOffsetConst, cg), xmmLowReg, cg);
   generateRegImmInstruction(TR::InstOpCode::SUB4RegImm4, node, lengthReg, 8, cg);

   generateRegImmInstruction(TR::InstOpCode::ADD4RegImm4, node, srcOffsetReg, 8, cg);
   generateRegImmInstruction(TR::InstOpCode::ADD4RegImm4, node, destOffsetReg, 16, cg);

   generateLabelInstruction(TR::InstOpCode::label, node, afterCopy8Label, cg);

   // handle residual (< 8 bytes left) & jump to copy instructions based on the number of bytes left
   // calculate how many bytes to skip based on length;

   const int copy_instruction_size = 5  // size of MOVZXReg2Mem1
                                    +4; // size of S2MemReg

   // since copy_instruction_size could change depending on which registers are allocated to scratchReg, srcOffsetReg and destOffsetReg
   // we reserve them to be eax, ecx, edx, respectively

   generateRegRegImmInstruction(TR::InstOpCode::IMUL4RegRegImm4, node, lengthReg, lengthReg, -copy_instruction_size, cg);
   generateRegImmInstruction(TR::InstOpCode::ADD4RegImm4, node, lengthReg, copy_instruction_size * 7, cg);

   bool is64bit = cg->comp()->target().is64Bit();
   // calculate address to jump too

   TR::MemoryReference *residueLabelMR = generateX86MemoryReference(copyResidueLabel, cg);

   if (cg->comp()->target().is64Bit() && residueLabelMR->getAddressRegister())
      {
      deps->addPostCondition(residueLabelMR->getAddressRegister(), TR::RealRegister::NoReg, cg);
      }

   generateRegMemInstruction(TR::InstOpCode::LEARegMem(is64bit), node, scratchReg, residueLabelMR, cg);
   generateRegRegInstruction(TR::InstOpCode::ADDRegReg(is64bit), node, lengthReg, scratchReg, cg);

   generateRegMemInstruction(TR::InstOpCode::LEARegMem(is64bit), node, srcOffsetReg, generateX86MemoryReference(srcBufferReg, srcOffsetReg, 0, 0, cg), cg);
   generateRegMemInstruction(TR::InstOpCode::LEARegMem(is64bit), node, destOffsetReg, generateX86MemoryReference(destBufferReg, destOffsetReg, 0, 0, cg), cg);

   generateRegInstruction(TR::InstOpCode::JMPReg, node, lengthReg, cg);

   generateLabelInstruction(TR::InstOpCode::label, node, copyResidueLabel, cg);

   for (int i = 0; i < 7; i++)
      {
      generateRegMemInstruction(TR::InstOpCode::MOVZXReg2Mem1, node, scratchReg, generateX86MemoryReference(srcOffsetReg, headerOffsetConst + 6 - i, cg), cg);
      generateMemRegInstruction(TR::InstOpCode::S2MemReg, node, generateX86MemoryReference(destOffsetReg, headerOffsetConst + 2 * (6 - i), cg), scratchReg, cg);
      }

   deps->stopAddingConditions();
   generateLabelInstruction(TR::InstOpCode::label, node, doneLabel, deps, cg);
   doneLabel->setEndInternalControlFlow();

   cg->stopUsingRegister(srcOffsetReg);
   cg->stopUsingRegister(destOffsetReg);
   cg->stopUsingRegister(lengthReg);

   cg->stopUsingRegister(xmmHighReg);
   cg->stopUsingRegister(xmmLowReg);
   cg->stopUsingRegister(zeroReg);
   cg->stopUsingRegister(scratchReg);

   for (int i = 0; i < 5; i++)
      {
      cg->decReferenceCount(node->getChild(i));
      }

   return NULL;
   }

TR::Register *
J9::X86::TreeEvaluator::encodeUTF16Evaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // tree looks like:
   // icall com.ibm.jit.JITHelpers.encodeUTF16{Big,Little}()
   //    input ptr
   //    output ptr
   //    input length (in elements)
   // Number of elements translated is returned

   TR::MethodSymbol *symbol = node->getSymbol()->castToMethodSymbol();
   bool bigEndian = symbol->getRecognizedMethod() == TR::com_ibm_jit_JITHelpers_transformedEncodeUTF16Big;

   // Set up register dependencies
   const int gprClobberCount = 2;
   const int maxFprClobberCount = 5;
   const int fprClobberCount = bigEndian ? 5 : 4; // xmm4 only needed for big-endian
   TR::Register *srcPtrReg, *dstPtrReg, *lengthReg, *resultReg;
   TR::Register *gprClobbers[gprClobberCount], *fprClobbers[maxFprClobberCount];
   bool killSrc = TR::TreeEvaluator::stopUsingCopyRegAddr(node->getChild(0), srcPtrReg, cg);
   bool killDst = TR::TreeEvaluator::stopUsingCopyRegAddr(node->getChild(1), dstPtrReg, cg);
   bool killLen = TR::TreeEvaluator::stopUsingCopyRegInteger(node->getChild(2), lengthReg, cg);
   resultReg = cg->allocateRegister();
   for (int i = 0; i < gprClobberCount; i++)
      gprClobbers[i] = cg->allocateRegister();
   for (int i = 0; i < fprClobberCount; i++)
      fprClobbers[i] = cg->allocateRegister(TR_FPR);

   int depCount = 11;
   TR::RegisterDependencyConditions *deps =
      generateRegisterDependencyConditions((uint8_t)0, depCount, cg);

   deps->addPostCondition(srcPtrReg, TR::RealRegister::esi, cg);
   deps->addPostCondition(dstPtrReg, TR::RealRegister::edi, cg);
   deps->addPostCondition(lengthReg, TR::RealRegister::edx, cg);
   deps->addPostCondition(resultReg, TR::RealRegister::eax, cg);

   deps->addPostCondition(gprClobbers[0], TR::RealRegister::ecx, cg);
   deps->addPostCondition(gprClobbers[1], TR::RealRegister::ebx, cg);

   deps->addPostCondition(fprClobbers[0], TR::RealRegister::xmm0, cg);
   deps->addPostCondition(fprClobbers[1], TR::RealRegister::xmm1, cg);
   deps->addPostCondition(fprClobbers[2], TR::RealRegister::xmm2, cg);
   deps->addPostCondition(fprClobbers[3], TR::RealRegister::xmm3, cg);
   if (bigEndian)
      deps->addPostCondition(fprClobbers[4], TR::RealRegister::xmm4, cg);

   deps->stopAddingConditions();

   // Generate helper call
   TR_RuntimeHelper helper;
   if (cg->comp()->target().is64Bit())
      helper = bigEndian ? TR_AMD64encodeUTF16Big : TR_AMD64encodeUTF16Little;
   else
      helper = bigEndian ? TR_IA32encodeUTF16Big : TR_IA32encodeUTF16Little;

   generateHelperCallInstruction(node, helper, deps, cg);

   // Free up registers
   for (int i = 0; i < gprClobberCount; i++)
      cg->stopUsingRegister(gprClobbers[i]);
   for (int i = 0; i < fprClobberCount; i++)
      cg->stopUsingRegister(fprClobbers[i]);

   for (uint16_t i = 0; i < node->getNumChildren(); i++)
      cg->decReferenceCount(node->getChild(i));

   TR_LiveRegisters *liveRegs = cg->getLiveRegisters(TR_GPR);
   if (killSrc)
      liveRegs->registerIsDead(srcPtrReg);
   if (killDst)
      liveRegs->registerIsDead(dstPtrReg);
   if (killLen)
      liveRegs->registerIsDead(lengthReg);

   node->setRegister(resultReg);
   return resultReg;
   }


/*
 * The CaseConversionManager is used to store info about the conversion. It defines the lower bound and upper bound value depending on
 * whether it's a toLower or toUpper case conversion. It also chooses byte or word data type depending on whether it's compressed string or not.
 * The stringCaseConversionHelper queries the manager for those info when generating the actual instructions.
 */
class J9::X86::TreeEvaluator::CaseConversionManager {
   public:
   CaseConversionManager(bool isCompressedString, bool toLowerCase):_isCompressedString(isCompressedString), _toLowerCase(toLowerCase)
      {
      if (isCompressedString)
         {
         static uint8_t UPPERCASE_A_ASCII_MINUS1_bytes[] =
            {
            'A'-1, 'A'-1, 'A'-1, 'A'-1,
            'A'-1, 'A'-1, 'A'-1, 'A'-1,
            'A'-1, 'A'-1, 'A'-1, 'A'-1,
            'A'-1, 'A'-1, 'A'-1, 'A'-1
            };

         static uint8_t UPPERCASE_Z_ASCII_bytes[] =
            {
            'Z', 'Z', 'Z', 'Z',
            'Z', 'Z', 'Z', 'Z',
            'Z', 'Z', 'Z', 'Z',
            'Z', 'Z', 'Z', 'Z'
            };

         static uint8_t LOWERCASE_A_ASCII_MINUS1_bytes[] =
            {
            'a'-1, 'a'-1, 'a'-1, 'a'-1,
            'a'-1, 'a'-1, 'a'-1, 'a'-1,
            'a'-1, 'a'-1, 'a'-1, 'a'-1,
            'a'-1, 'a'-1, 'a'-1, 'a'-1
            };

         static uint8_t LOWERCASE_Z_ASCII_bytes[] =
            {
            'z', 'z', 'z', 'z',
            'z', 'z', 'z', 'z',
            'z', 'z', 'z', 'z',
            'z', 'z', 'z', 'z',
            };

         static uint8_t CONVERSION_DIFF_bytes[] =
            {
            0x20, 0x20, 0x20, 0x20,
            0x20, 0x20, 0x20, 0x20,
            0x20, 0x20, 0x20, 0x20,
            0x20, 0x20, 0x20, 0x20,
            };

         static uint16_t ASCII_UPPERBND_bytes[] =
            {
            0x7f, 0x7f, 0x7f, 0x7f,
            0x7f, 0x7f, 0x7f, 0x7f,
            0x7f, 0x7f, 0x7f, 0x7f,
            0x7f, 0x7f, 0x7f, 0x7f,
            };

         if (toLowerCase)
            {
            _lowerBndMinus1 = UPPERCASE_A_ASCII_MINUS1_bytes;
            _upperBnd = UPPERCASE_Z_ASCII_bytes;
            }
         else
            {
            _lowerBndMinus1 = LOWERCASE_A_ASCII_MINUS1_bytes;
            _upperBnd = LOWERCASE_Z_ASCII_bytes;
            }
         _conversionDiff = CONVERSION_DIFF_bytes;
         _asciiMax = ASCII_UPPERBND_bytes;
         }
      else
         {
         static uint16_t UPPERCASE_A_ASCII_MINUS1_words[] =
            {
            'A'-1, 'A'-1, 'A'-1, 'A'-1,
            'A'-1, 'A'-1, 'A'-1, 'A'-1
            };

         static uint16_t LOWERCASE_A_ASCII_MINUS1_words[] =
            {
            'a'-1, 'a'-1, 'a'-1, 'a'-1,
            'a'-1, 'a'-1, 'a'-1, 'a'-1
            };

         static uint16_t UPPERCASE_Z_ASCII_words[] =
            {
            'Z', 'Z', 'Z', 'Z',
            'Z', 'Z', 'Z', 'Z'
            };

         static uint16_t LOWERCASE_Z_ASCII_words[] =
            {
            'z', 'z', 'z', 'z',
            'z', 'z', 'z', 'z'
            };

         static uint16_t CONVERSION_DIFF_words[] =
            {
            0x20, 0x20, 0x20, 0x20,
            0x20, 0x20, 0x20, 0x20
            };
         static uint16_t ASCII_UPPERBND_words[] =
            {
            0x7f, 0x7f, 0x7f, 0x7f,
            0x7f, 0x7f, 0x7f, 0x7f
            };

         if (toLowerCase)
            {
            _lowerBndMinus1 = UPPERCASE_A_ASCII_MINUS1_words;
            _upperBnd = UPPERCASE_Z_ASCII_words;
            }
         else
            {
            _lowerBndMinus1 = LOWERCASE_A_ASCII_MINUS1_words;
            _upperBnd = LOWERCASE_Z_ASCII_words;
            }
         _conversionDiff = CONVERSION_DIFF_words;
         _asciiMax = ASCII_UPPERBND_words;
         }
      };

   inline bool isCompressedString(){return _isCompressedString;};
   inline bool toLowerCase(){return _toLowerCase;};
   inline void * getLowerBndMinus1(){ return _lowerBndMinus1; };
   inline void * getUpperBnd(){ return _upperBnd; };
   inline void * getConversionDiff(){ return _conversionDiff; };
   inline void * getAsciiMax(){ return _asciiMax; };

   private:
   void * _lowerBndMinus1;
   void * _upperBnd;
   void * _asciiMax;
   void * _conversionDiff;
   bool _isCompressedString;
   bool _toLowerCase;
};

TR::Register *
J9::X86::TreeEvaluator::toUpperIntrinsicLatin1Evaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   CaseConversionManager manager(true /* isCompressedString */, false /* toLowerCase */);
   return TR::TreeEvaluator::stringCaseConversionHelper(node, cg, manager);
   }


TR::Register *
J9::X86::TreeEvaluator::toLowerIntrinsicLatin1Evaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   CaseConversionManager manager(true/* isCompressedString */, true /* toLowerCase */);
   return TR::TreeEvaluator::stringCaseConversionHelper(node, cg, manager);
   }

TR::Register *
J9::X86::TreeEvaluator::toUpperIntrinsicUTF16Evaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   CaseConversionManager manager(false /* isCompressedString */, false /* toLowerCase */);
   return TR::TreeEvaluator::stringCaseConversionHelper(node, cg, manager);
   }

TR::Register *
J9::X86::TreeEvaluator::toLowerIntrinsicUTF16Evaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   CaseConversionManager manager(false /* isCompressedString */, true /* toLowerCase */);
   return TR::TreeEvaluator::stringCaseConversionHelper(node, cg, manager);
   }

static TR::Register* allocateRegAndAddCondition(TR::CodeGenerator *cg, TR::RegisterDependencyConditions * deps, TR_RegisterKinds rk=TR_GPR)
   {
   TR::Register* reg = cg->allocateRegister(rk);
   deps->addPostCondition(reg, TR::RealRegister::NoReg, cg);
   deps->addPreCondition(reg, TR::RealRegister::NoReg, cg);
   return reg;
   }


/**
 * \brief This evaluator is used to perform string toUpper and toLower conversion.
 *
 * This JIT HW optimized conversion helper is designed to convert strings that contains only ascii characters.
 * If a string contains non ascii characters, HW optimized routine will return NULL and fall back to the software implementation, which is able to convert a broader range of characters.
 *
 * There are the following steps in the generated assembly code:
 *   1. preparation (load value into register, calculate length etc)
 *   2. vectorized case conversion loop
 *   3. handle residue with non vectorized case conversion loop
 *   4. handle invalid case
 *
 * \param node
 * \param cg
 * \param manager Contains info about the conversion: whether it's toUpper or toLower conversion, the valid range of characters, etc
 *
 * This version does not support discontiguous arrays
 */
TR::Register *
J9::X86::TreeEvaluator::stringCaseConversionHelper(TR::Node *node, TR::CodeGenerator *cg, CaseConversionManager &manager)
   {
   #define iComment(str) if (debug) debug->addInstructionComment(cursor, (const_cast<char*>(str)));
   TR::RegisterDependencyConditions *deps = generateRegisterDependencyConditions((uint8_t)14, (uint8_t)14, cg);
   TR::Register *srcArray = cg->evaluate(node->getChild(1));
   deps->addPostCondition(srcArray, TR::RealRegister::NoReg, cg);
   deps->addPreCondition(srcArray, TR::RealRegister::NoReg, cg);

   TR::Register *dstArray = cg->evaluate(node->getChild(2));
   deps->addPostCondition(dstArray, TR::RealRegister::NoReg, cg);
   deps->addPreCondition(dstArray, TR::RealRegister::NoReg, cg);

   TR::Register *length = cg->intClobberEvaluate(node->getChild(3));
   deps->addPostCondition(length, TR::RealRegister::NoReg, cg);
   deps->addPreCondition(length, TR::RealRegister::NoReg, cg);

   TR::Register* counter = allocateRegAndAddCondition(cg, deps);
   TR::Register* residueStartLength = allocateRegAndAddCondition(cg, deps);
   TR::Register *singleChar = residueStartLength; // residueStartLength and singleChar do not overlap and can share the same register
   TR::Register *result = allocateRegAndAddCondition(cg, deps);

   TR::Register* xmmRegLowerBndMinus1 = allocateRegAndAddCondition(cg, deps, TR_FPR); // 'A-1' for toLowerCase, 'a-1' for toUpperCase
   TR::Register* xmmRegUpperBnd = allocateRegAndAddCondition(cg, deps, TR_FPR);// 'Z-1' for toLowerCase, 'z-1' for toUpperCase
   TR::Register* xmmRegConversionDiff = allocateRegAndAddCondition(cg, deps, TR_FPR);
   TR::Register* xmmRegMinus1 = allocateRegAndAddCondition(cg, deps, TR_FPR);
   TR::Register* xmmRegAsciiUpperBnd = allocateRegAndAddCondition(cg, deps, TR_FPR);
   TR::Register* xmmRegArrayContentCopy0 = allocateRegAndAddCondition(cg, deps, TR_FPR);
   TR::Register* xmmRegArrayContentCopy1 = allocateRegAndAddCondition(cg, deps, TR_FPR);
   TR::Register* xmmRegArrayContentCopy2 = allocateRegAndAddCondition(cg, deps, TR_FPR);
   TR_Debug *debug = cg->getDebug();
   TR::Instruction * cursor = NULL;

   uint32_t strideSize = 16;
   uintptr_t headerSize = TR::Compiler->om.contiguousArrayHeaderSizeInBytes();

   static uint16_t MINUS1[] =
      {
      0xffff, 0xffff, 0xffff, 0xffff,
      0xffff, 0xffff, 0xffff, 0xffff,
      };

   TR::LabelSymbol *failLabel = generateLabelSymbol(cg);
   // Under decompressed string case for 32bits platforms, bail out if string is larger than INT_MAX32/2 since # character to # byte
   // conversion will cause overflow.
   if (!cg->comp()->target().is64Bit() && !manager.isCompressedString())
      {
      generateRegImmInstruction(TR::InstOpCode::CMPRegImm4(), node, length, (uint16_t) 0x8000, cg);
      generateLabelInstruction(TR::InstOpCode::JGE4, node, failLabel, cg);
      }

   // 1. preparation (load value into registers, calculate length etc)
   auto lowerBndMinus1 = generateX86MemoryReference(cg->findOrCreate16ByteConstant(node, manager.getLowerBndMinus1()), cg);
   cursor = generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, xmmRegLowerBndMinus1, lowerBndMinus1, cg); iComment("lower bound ascii value minus one");

   auto upperBnd = generateX86MemoryReference(cg->findOrCreate16ByteConstant(node, manager.getUpperBnd()), cg);
   cursor = generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, xmmRegUpperBnd, upperBnd, cg); iComment("upper bound ascii value");

   auto conversionDiff = generateX86MemoryReference(cg->findOrCreate16ByteConstant(node, manager.getConversionDiff()), cg);
   cursor = generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, xmmRegConversionDiff, conversionDiff, cg); iComment("case conversion diff value");

   auto minus1 = generateX86MemoryReference(cg->findOrCreate16ByteConstant(node, MINUS1), cg);
   cursor = generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, xmmRegMinus1, minus1, cg); iComment("-1");

   auto asciiUpperBnd = generateX86MemoryReference(cg->findOrCreate16ByteConstant(node, manager.getAsciiMax()), cg);
   cursor = generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, xmmRegAsciiUpperBnd, asciiUpperBnd, cg); iComment("maximum ascii value ");

   generateRegImmInstruction(TR::InstOpCode::MOV4RegImm4, node, result, 1, cg);

   // initialize the loop counter
   cursor = generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, counter, counter, cg); iComment("initialize loop counter");

   //calculate the residueStartLength. Later instructions compare the counter with this length and decide when to jump to the residue handling sequence
   generateRegRegInstruction(TR::InstOpCode::MOVRegReg(), node, residueStartLength, length, cg);
   generateRegImmInstruction(TR::InstOpCode::SUBRegImms(), node, residueStartLength, strideSize-1, cg);

   // 2. vectorized case conversion loop
   TR::LabelSymbol *startLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *endLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *residueStartLabel = generateLabelSymbol(cg);
   TR::LabelSymbol *storeToArrayLabel = generateLabelSymbol(cg);

   startLabel->setStartInternalControlFlow();
   endLabel->setEndInternalControlFlow();
   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

   TR::LabelSymbol *caseConversionMainLoopLabel = generateLabelSymbol(cg);
   generateLabelInstruction(TR::InstOpCode::label, node, caseConversionMainLoopLabel, cg);
   generateRegRegInstruction(TR::InstOpCode::CMPRegReg(), node, counter, residueStartLength, cg);
   generateLabelInstruction(TR::InstOpCode::JGE4, node, residueStartLabel, cg);

   auto srcArrayMemRef = generateX86MemoryReference(srcArray, counter, 0, headerSize, cg);
   generateRegMemInstruction(TR::InstOpCode::MOVDQURegMem, node, xmmRegArrayContentCopy0, srcArrayMemRef, cg);

   //detect invalid characters
   generateRegRegInstruction(TR::InstOpCode::MOVDQURegReg, node, xmmRegArrayContentCopy1, xmmRegArrayContentCopy0, cg);
   generateRegRegInstruction(TR::InstOpCode::MOVDQURegReg, node, xmmRegArrayContentCopy2, xmmRegArrayContentCopy0, cg);
   cursor = generateRegRegInstruction(manager.isCompressedString()? TR::InstOpCode::PCMPGTBRegReg: TR::InstOpCode::PCMPGTWRegReg, node,
                             xmmRegArrayContentCopy1, xmmRegMinus1, cg); iComment(" > -1");
   cursor = generateRegRegInstruction(manager.isCompressedString()? TR::InstOpCode::PCMPGTBRegReg: TR::InstOpCode::PCMPGTWRegReg, node,
                             xmmRegArrayContentCopy2, xmmRegAsciiUpperBnd, cg); iComment(" > maximum ascii value");
   cursor = generateRegRegInstruction(TR::InstOpCode::PANDNRegReg, node, xmmRegArrayContentCopy2, xmmRegArrayContentCopy1, cg); iComment(" >-1 && !(> maximum ascii value) valid when all bits are set");
   cursor = generateRegRegInstruction(TR::InstOpCode::PXORRegReg, node, xmmRegArrayContentCopy2, xmmRegMinus1, cg); iComment("reverse all bits");
   generateRegRegInstruction(TR::InstOpCode::PTESTRegReg, node, xmmRegArrayContentCopy2, xmmRegArrayContentCopy2, cg);
   generateLabelInstruction(TR::InstOpCode::JNE4, node, failLabel, cg); iComment("jump out if invalid chars are detected");

   //calculate case conversion with vector registers
   generateRegRegInstruction(TR::InstOpCode::MOVDQURegReg, node, xmmRegArrayContentCopy1, xmmRegArrayContentCopy0, cg);
   generateRegRegInstruction(TR::InstOpCode::MOVDQURegReg, node, xmmRegArrayContentCopy2, xmmRegArrayContentCopy0, cg);
   cursor = generateRegRegInstruction(manager.isCompressedString()? TR::InstOpCode::PCMPGTBRegReg: TR::InstOpCode::PCMPGTWRegReg, node,
                             xmmRegArrayContentCopy0, xmmRegLowerBndMinus1, cg);  iComment(manager.toLowerCase() ? " > 'A-1'" : "> 'a-1'");
   cursor = generateRegRegInstruction(manager.isCompressedString()? TR::InstOpCode::PCMPGTBRegReg: TR::InstOpCode::PCMPGTWRegReg, node,
                             xmmRegArrayContentCopy1, xmmRegUpperBnd, cg);  iComment(manager.toLowerCase()? " > 'Z'" : " > 'z'");
   cursor = generateRegRegInstruction(TR::InstOpCode::PANDNRegReg, node, xmmRegArrayContentCopy1, xmmRegArrayContentCopy0, cg);  iComment(const_cast<char*> (manager.toLowerCase()? " >='A' && !( >'Z')": " >='a' && !( >'z')"));
   generateRegRegInstruction(TR::InstOpCode::PANDRegReg, node, xmmRegArrayContentCopy1, xmmRegConversionDiff, cg);

   if (manager.toLowerCase())
      generateRegRegInstruction(manager.isCompressedString()? TR::InstOpCode::PADDBRegReg: TR::InstOpCode::PADDWRegReg, node,
                                xmmRegArrayContentCopy2, xmmRegArrayContentCopy1, cg);
   else
      generateRegRegInstruction(manager.isCompressedString()? TR::InstOpCode::PSUBBRegReg: TR::InstOpCode::PSUBWRegReg, node,
                                xmmRegArrayContentCopy2, xmmRegArrayContentCopy1, cg);

   auto dstArrayMemRef = generateX86MemoryReference(dstArray, counter, 0, headerSize, cg);
   generateMemRegInstruction(TR::InstOpCode::MOVDQUMemReg, node, dstArrayMemRef, xmmRegArrayContentCopy2, cg);
   generateRegImmInstruction(TR::InstOpCode::ADDRegImms(), node, counter, strideSize, cg);
   generateLabelInstruction(TR::InstOpCode::JMP4, node, caseConversionMainLoopLabel, cg);

   // 3. handle residue with non vectorized case conversion loop
   generateLabelInstruction(TR::InstOpCode::label, node, residueStartLabel, cg);
   generateRegRegInstruction(TR::InstOpCode::CMPRegReg(), node, counter, length, cg);
   generateLabelInstruction(TR::InstOpCode::JGE4, node, endLabel, cg);
   srcArrayMemRef = generateX86MemoryReference(srcArray, counter, 0, headerSize, cg);
   generateRegMemInstruction( manager.isCompressedString()? TR::InstOpCode::MOVZXReg4Mem1: TR::InstOpCode::MOVZXReg4Mem2, node, singleChar, srcArrayMemRef, cg);

   // use unsigned compare to detect invalid range
   generateRegImmInstruction(TR::InstOpCode::CMP4RegImms, node, singleChar, 0x7F, cg);
   generateLabelInstruction(TR::InstOpCode::JA4, node, failLabel, cg);

   generateRegImmInstruction(TR::InstOpCode::CMP4RegImms, node, singleChar, manager.toLowerCase()? 'A': 'a', cg);
   generateLabelInstruction(TR::InstOpCode::JB4, node, storeToArrayLabel, cg);

   generateRegImmInstruction(TR::InstOpCode::CMP4RegImms, node, singleChar, manager.toLowerCase()? 'Z': 'z', cg);
   generateLabelInstruction(TR::InstOpCode::JA4, node, storeToArrayLabel, cg);

   if (manager.toLowerCase())
      generateRegMemInstruction(TR::InstOpCode::LEARegMem(),
                                node,
                                singleChar,
                                generateX86MemoryReference(singleChar, 0x20, cg),
                                cg);

   else generateRegImmInstruction(TR::InstOpCode::SUB4RegImms, node, singleChar, 0x20, cg);

   generateLabelInstruction(TR::InstOpCode::label, node, storeToArrayLabel, cg);

   dstArrayMemRef = generateX86MemoryReference(dstArray, counter, 0, headerSize, cg);
   generateMemRegInstruction(manager.isCompressedString()? TR::InstOpCode::S1MemReg: TR::InstOpCode::S2MemReg, node, dstArrayMemRef, singleChar, cg);
   generateRegImmInstruction(TR::InstOpCode::ADDRegImms(), node, counter, manager.isCompressedString()? 1: 2, cg);
   generateLabelInstruction(TR::InstOpCode::JMP4, node, residueStartLabel, cg);

   // 4. handle invalid case
   generateLabelInstruction(TR::InstOpCode::label, node, failLabel, cg);
   generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, result, result, cg);

   generateLabelInstruction(TR::InstOpCode::label, node, endLabel, deps, cg);
   node->setRegister(result);

   cg->stopUsingRegister(length);
   cg->stopUsingRegister(counter);
   cg->stopUsingRegister(residueStartLength);

   cg->stopUsingRegister(xmmRegLowerBndMinus1);
   cg->stopUsingRegister(xmmRegUpperBnd);
   cg->stopUsingRegister(xmmRegConversionDiff);
   cg->stopUsingRegister(xmmRegMinus1);
   cg->stopUsingRegister(xmmRegAsciiUpperBnd);
   cg->stopUsingRegister(xmmRegArrayContentCopy0);
   cg->stopUsingRegister(xmmRegArrayContentCopy1);
   cg->stopUsingRegister(xmmRegArrayContentCopy2);


   cg->decReferenceCount(node->getChild(0));
   cg->decReferenceCount(node->getChild(1));
   cg->decReferenceCount(node->getChild(2));
   cg->decReferenceCount(node->getChild(3));
   return result;
   }


/*
 *
 * Generates instructions to fill in the J9JITWatchedStaticFieldData.fieldAddress, J9JITWatchedStaticFieldData.fieldClass for static fields,
 * and J9JITWatchedInstanceFieldData.offset for instance fields at runtime. Used for fieldwatch support.
 * Fill in the J9JITWatchedStaticFieldData.fieldAddress, J9JITWatchedStaticFieldData.fieldClass for static field
 * and J9JITWatchedInstanceFieldData.offset for instance field
 *
 * cmp J9JITWatchedStaticFieldData.fieldAddress / J9JITWatchedInstanceFieldData.offset,  -1
 * je unresolvedLabel
 * restart Label:
 * ....
 *
 * unresolvedLabel:
 * mov J9JITWatchedStaticFieldData.fieldClass J9Class (static field only)
 * call helper
 * mov J9JITWatchedStaticFieldData.fieldAddress / J9JITWatchedInstanceFieldData.offset  resultReg
 * jmp restartLabel
 */
void
J9::X86::TreeEvaluator::generateFillInDataBlockSequenceForUnresolvedField (TR::CodeGenerator *cg, TR::Node *node, TR::Snippet *dataSnippet, bool isWrite, TR::Register *sideEffectRegister, TR::Register *dataSnippetRegister)
   {
   TR::Compilation *comp = cg->comp();
   TR::SymbolReference *symRef = node->getSymbolReference();
   bool is64Bit = comp->target().is64Bit();
   bool isStatic = symRef->getSymbol()->getKind() == TR::Symbol::IsStatic;
   TR_RuntimeHelper helperIndex = isWrite? (isStatic ?  TR_jitResolveStaticFieldSetterDirect: TR_jitResolveFieldSetterDirect):
                                           (isStatic ?  TR_jitResolveStaticFieldDirect: TR_jitResolveFieldDirect);
   TR::Linkage *linkage = cg->getLinkage(runtimeHelperLinkage(helperIndex));
   auto linkageProperties = linkage->getProperties();
   intptr_t offsetInDataBlock = isStatic ? offsetof(J9JITWatchedStaticFieldData, fieldAddress): offsetof(J9JITWatchedInstanceFieldData, offset);

   TR::LabelSymbol* startLabel = generateLabelSymbol(cg);
   TR::LabelSymbol* endLabel = generateLabelSymbol(cg);
   TR::LabelSymbol* unresolveLabel = generateLabelSymbol(cg);
   startLabel->setStartInternalControlFlow();
   endLabel->setEndInternalControlFlow();

   // 64bit needs 2 argument registers (return register and first argument are the same),
   // 32bit only one return register
   // both 64/32bits need dataBlockReg
   uint8_t numOfConditions = is64Bit ? 3: 2;
   if (isStatic) // needs fieldClassReg
      {
      numOfConditions++;
      }
   TR::RegisterDependencyConditions  *deps =  generateRegisterDependencyConditions(numOfConditions, numOfConditions, cg);
   TR::Register *resultReg = NULL;
   TR::Register *dataBlockReg = cg->allocateRegister();
   deps->addPreCondition(dataBlockReg, TR::RealRegister::NoReg, cg);
   deps->addPostCondition(dataBlockReg, TR::RealRegister::NoReg, cg);

   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);
   generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, dataBlockReg, generateX86MemoryReference(dataSnippet->getSnippetLabel(), cg), cg);
   generateMemImmInstruction(TR::InstOpCode::CMPMemImms(), node, generateX86MemoryReference(dataBlockReg, offsetInDataBlock, cg), -1, cg);
   generateLabelInstruction(TR::InstOpCode::JE4, node, unresolveLabel, cg);

      {
      TR_OutlinedInstructionsGenerator og(unresolveLabel, node ,cg);
      if (isStatic)
         {
         // Fills in J9JITWatchedStaticFieldData.fieldClass
         TR::Register *fieldClassReg;
         if (isWrite)
            {
            fieldClassReg = cg->allocateRegister();
            generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, fieldClassReg, generateX86MemoryReference(sideEffectRegister, comp->fej9()->getOffsetOfClassFromJavaLangClassField(), cg), cg);
            }
         else
            {
            fieldClassReg = sideEffectRegister;
            }
         generateMemRegInstruction(TR::InstOpCode::SMemReg(is64Bit), node, generateX86MemoryReference(dataBlockReg, (intptr_t)(offsetof(J9JITWatchedStaticFieldData, fieldClass)), cg), fieldClassReg, cg);
         deps->addPreCondition(fieldClassReg, TR::RealRegister::NoReg, cg);
         deps->addPostCondition(fieldClassReg, TR::RealRegister::NoReg, cg);
         if (isWrite)
            {
            cg->stopUsingRegister(fieldClassReg);
            }
         }

      TR::ResolvedMethodSymbol *methodSymbol = node->getByteCodeInfo().getCallerIndex() == -1 ? comp->getMethodSymbol(): comp->getInlinedResolvedMethodSymbol(node->getByteCodeInfo().getCallerIndex());
      if (is64Bit)
         {
         TR::Register *cpAddressReg = cg->allocateRegister();
         TR::Register *cpIndexReg = cg->allocateRegister();
         generateRegImm64SymInstruction(TR::InstOpCode::MOV8RegImm64, node, cpAddressReg, (uintptr_t) methodSymbol->getResolvedMethod()->constantPool(), comp->getSymRefTab()->findOrCreateConstantPoolAddressSymbolRef(methodSymbol), cg);
         generateRegImmInstruction(TR::InstOpCode::MOV8RegImm4, node, cpIndexReg, symRef->getCPIndex(), cg);
         deps->addPreCondition(cpAddressReg, linkageProperties.getArgumentRegister(0, false /* isFloat */), cg);
         deps->addPostCondition(cpAddressReg, linkageProperties.getArgumentRegister(0, false /* isFloat */), cg);
         deps->addPreCondition(cpIndexReg, linkageProperties.getArgumentRegister(1, false /* isFloat */), cg);
         deps->addPostCondition(cpIndexReg, linkageProperties.getArgumentRegister(1, false /* isFloat */), cg);
         cg->stopUsingRegister(cpIndexReg);
         resultReg = cpAddressReg; // for 64bit private linkage both the first argument reg and the return reg are rax
         }
      else
         {
         generateImmInstruction(TR::InstOpCode::PUSHImm4, node, symRef->getCPIndex(), cg);
         generateImmSymInstruction(TR::InstOpCode::PUSHImm4, node, (uintptr_t) methodSymbol->getResolvedMethod()->constantPool(), comp->getSymRefTab()->findOrCreateConstantPoolAddressSymbolRef(methodSymbol), cg);
         resultReg = cg->allocateRegister();
         deps->addPreCondition(resultReg, linkageProperties.getIntegerReturnRegister(), cg);
         deps->addPostCondition(resultReg, linkageProperties.getIntegerReturnRegister(), cg);
         }
      TR::Instruction *call = generateHelperCallInstruction(node, helperIndex, NULL, cg);
      call->setNeedsGCMap(0xFF00FFFF);

      /*
      For instance field offset, the result returned by the vmhelper includes header size.
      subtract the header size to get the offset needed by field watch helpers
      */
      if (!isStatic)
         {
         generateRegImmInstruction(TR::InstOpCode::SubRegImm4(is64Bit, false /*isWithBorrow*/), node, resultReg, TR::Compiler->om.objectHeaderSizeInBytes(), cg);
         }

      //store result into J9JITWatchedStaticFieldData.fieldAddress / J9JITWatchedInstanceFieldData.offset
      generateMemRegInstruction(TR::InstOpCode::SMemReg(is64Bit), node, generateX86MemoryReference(dataBlockReg, offsetInDataBlock, cg), resultReg, cg);
      generateLabelInstruction(TR::InstOpCode::JMP4, node, endLabel, cg);

      og.endOutlinedInstructionSequence();
      }

   deps->stopAddingConditions();
   generateLabelInstruction(TR::InstOpCode::label, node, endLabel, deps, cg);
   cg->stopUsingRegister(dataBlockReg);
   cg->stopUsingRegister(resultReg);
   }

/*
 * Generate the reporting field access helper call with required arguments
 *
 * jitReportInstanceFieldRead
 * arg1 pointer to static data block
 * arg2 object being read
 *
 * jitReportInstanceFieldWrite
 * arg1 pointer to static data block
 * arg2 object being written to (represented by sideEffectRegister)
 * arg3 pointer to value being written
 *
 * jitReportStaticFieldRead
 * arg1 pointer to static data block
 *
 * jitReportStaticFieldWrite
 * arg1 pointer to static data block
 * arg2 pointer to value being written
 *
 */
void generateReportFieldAccessOutlinedInstructions(TR::Node *node, TR::LabelSymbol *endLabel, TR::Snippet *dataSnippet, bool isWrite, TR::RegisterDependencyConditions *deps, TR::CodeGenerator *cg, TR::Register *sideEffectRegister, TR::Register *valueReg)
   {
   bool is64Bit = cg->comp()->target().is64Bit();
   bool isInstanceField = node->getSymbolReference()->getSymbol()->getKind() != TR::Symbol::IsStatic;
   J9Method *owningMethod = (J9Method *)node->getOwningMethod();

   TR_RuntimeHelper helperIndex = isWrite ? (isInstanceField ? TR_jitReportInstanceFieldWrite: TR_jitReportStaticFieldWrite):
                                            (isInstanceField ? TR_jitReportInstanceFieldRead: TR_jitReportStaticFieldRead);

   TR::Linkage *linkage = cg->getLinkage(runtimeHelperLinkage(helperIndex));
   auto linkageProperties = linkage->getProperties();

   TR::Register *valueReferenceReg = NULL;
   TR::MemoryReference *valueMR = NULL;
   TR::Register *dataBlockReg = cg->allocateRegister();
   bool reuseValueReg = false;

   /*
    * For reporting field write, reference to the valueNode (valueNode is evaluated in valueReg) is needed so we need to store
    * the value on to a stack location first and pass the stack location address as an arguement
    * to the VM helper
    */
   if (isWrite)
      {
      valueMR = cg->machine()->getDummyLocalMR(node->getType());
      if (!valueReg->getRegisterPair())
         {
         if (valueReg->getKind() == TR_GPR)
            {
            TR::AutomaticSymbol *autoSymbol = valueMR->getSymbolReference().getSymbol()->getAutoSymbol();
            generateMemRegInstruction(TR::InstOpCode::SMemReg(autoSymbol->getRoundedSize() == 8), node, valueMR, valueReg, cg);
            }
         else if (valueReg->isSinglePrecision())
            generateMemRegInstruction(TR::InstOpCode::MOVSSMemReg, node, valueMR, valueReg, cg);
         else
            generateMemRegInstruction(TR::InstOpCode::MOVSDMemReg, node, valueMR, valueReg, cg);
         // valueReg and valueReferenceReg are different. Add conditions for valueReg here
         deps->addPreCondition(valueReg, TR::RealRegister::NoReg, cg);
         deps->addPostCondition(valueReg, TR::RealRegister::NoReg, cg);
         valueReferenceReg = cg->allocateRegister();
         }
      else
         { // 32bit long
         generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, valueMR, valueReg->getLowOrder(), cg);
         generateMemRegInstruction(TR::InstOpCode::SMemReg(), node, generateX86MemoryReference(*valueMR, 4, cg), valueReg->getHighOrder(), cg);

         // Add the dependency for higher half register here
         deps->addPostCondition(valueReg->getHighOrder(), TR::RealRegister::NoReg, cg);
         deps->addPreCondition(valueReg->getHighOrder(), TR::RealRegister::NoReg, cg);

         // on 32bit reuse lower half register to save one register
         // lower half register dependency will be added later when using as valueReferenceReg and a call argument
         // to keep consistency with the other call arguments
         valueReferenceReg = valueReg->getLowOrder();
         reuseValueReg = true;
         }

      //store the stack location into a register
      generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, valueReferenceReg, valueMR, cg);
      }

   generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, dataBlockReg, generateX86MemoryReference(dataSnippet->getSnippetLabel(), cg), cg);
   int numArgs = 0;
   if (is64Bit)
      {
      deps->addPreCondition(dataBlockReg, linkageProperties.getArgumentRegister(numArgs, false /* isFloat */), cg);
      deps->addPostCondition(dataBlockReg, linkageProperties.getArgumentRegister(numArgs, false /* isFloat */), cg);
      numArgs++;

      if (isInstanceField)
         {
         deps->addPreCondition(sideEffectRegister, linkageProperties.getArgumentRegister(numArgs, false /* isFloat */), cg);
         deps->addPostCondition(sideEffectRegister, linkageProperties.getArgumentRegister(numArgs, false /* isFloat */), cg);
         numArgs++;
         }

      if (isWrite)
         {
         deps->addPreCondition(valueReferenceReg, linkageProperties.getArgumentRegister(numArgs, false /* isFloat */), cg);
         deps->addPostCondition(valueReferenceReg, linkageProperties.getArgumentRegister(numArgs, false /* isFloat */), cg);
         }
      }
   else
      {
      if (isWrite)
         {
         generateRegInstruction(TR::InstOpCode::PUSHReg, node, valueReferenceReg, cg);
         deps->addPostCondition(valueReferenceReg, TR::RealRegister::NoReg, cg);
         deps->addPreCondition(valueReferenceReg, TR::RealRegister::NoReg, cg);
         }

      if (isInstanceField)
         {
         generateRegInstruction(TR::InstOpCode::PUSHReg, node, sideEffectRegister, cg);
         deps->addPreCondition(sideEffectRegister, TR::RealRegister::NoReg, cg);
         deps->addPostCondition(sideEffectRegister, TR::RealRegister::NoReg, cg);
         }
      generateRegInstruction(TR::InstOpCode::PUSHReg, node, dataBlockReg, cg);
      deps->addPreCondition(dataBlockReg, TR::RealRegister::NoReg, cg);
      deps->addPostCondition(dataBlockReg, TR::RealRegister::NoReg, cg);
      }

   TR::Instruction *call = generateHelperCallInstruction(node, helperIndex, NULL, cg);
   call->setNeedsGCMap(0xFF00FFFF);
   // Restore the value of lower part register
   if (isWrite && valueReg->getRegisterPair() && valueReg->getKind() == TR_GPR)
      generateRegMemInstruction(TR::InstOpCode::L4RegMem, node, valueReg->getLowOrder(), valueMR, cg);
   if (!reuseValueReg)
      cg->stopUsingRegister(valueReferenceReg);
   generateLabelInstruction(TR::InstOpCode::JMP4, node, endLabel, cg);
   cg->stopUsingRegister(dataBlockReg);
   }

/*
 * Get the number of register dependencies needed to generate the out-of-line sequence reporting field accesses
 */
static uint8_t getNumOfConditionsForReportFieldAccess(TR::Node *node, bool isResolved, bool isWrite, bool isInstanceField, TR::CodeGenerator *cg)
   {
   uint8_t numOfConditions = 1; // 1st arg is always the data block
   if (!isResolved || isInstanceField || cg->needClassAndMethodPointerRelocations())
      numOfConditions = numOfConditions+1; // classReg is needed in both cases.
   if (isWrite)
      {
      /* Field write report needs
       * a) value being written
       * b) the reference to the value being written
       *
       * The following cases are considered
       * 1. For 32bits using register pair(long), the valueReg is actually 2 registers,
       *    and valueReferenceReg reuses one reg in valueReg to avoid running out of registers on 32bits
       * 2. For 32bits and 64bits no register pair, valueReferenceReg and valueReg are 2 different registers
       */
      numOfConditions = numOfConditions + 2 ;
      }
   if (isInstanceField)
      numOfConditions = numOfConditions+1; // Instance field report needs the base object
   return numOfConditions;
   }

void
J9::X86::TreeEvaluator::generateTestAndReportFieldWatchInstructions(TR::CodeGenerator *cg, TR::Node *node, TR::Snippet *dataSnippet, bool isWrite, TR::Register *sideEffectRegister, TR::Register *valueReg, TR::Register *dataSnippetRegister)
   {
   bool isResolved = !node->getSymbolReference()->isUnresolved();
   TR::LabelSymbol* startLabel = generateLabelSymbol(cg);
   TR::LabelSymbol* endLabel = generateLabelSymbol(cg);
   TR::LabelSymbol* fieldReportLabel = generateLabelSymbol(cg);
   startLabel->setStartInternalControlFlow();
   endLabel->setEndInternalControlFlow();

   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

   TR::Register *fieldClassReg = NULL;
   TR::MemoryReference *classFlagsMemRef = NULL;
   TR_J9VMBase *fej9 = (TR_J9VMBase *)(cg->fe());
   bool isInstanceField = node->getOpCode().isIndirect();
   bool fieldClassNeedsRelocation = cg->needClassAndMethodPointerRelocations();

   if (isInstanceField)
      {
      TR::Register *objReg = sideEffectRegister;
      fieldClassReg = cg->allocateRegister();
      generateLoadJ9Class(node, fieldClassReg, objReg, cg);
      classFlagsMemRef = generateX86MemoryReference(fieldClassReg, (uintptr_t)(fej9->getOffsetOfClassFlags()), cg);
      }
   else
      {
      if (isResolved)
         {
         if (!fieldClassNeedsRelocation)
            {
            // For non-AOT (JIT and JITServer) compiles we don't need to use sideEffectRegister here as the class information is available to us at compile time.
            J9Class *fieldClass = static_cast<TR::J9WatchedStaticFieldSnippet *>(dataSnippet)->getFieldClass();
            classFlagsMemRef = generateX86MemoryReference((uintptr_t)fieldClass + fej9->getOffsetOfClassFlags(), cg);
            }
         else
            {
            // If this is an AOT compile, we generate instructions to load the fieldClass directly from the snippet because the fieldClass in an AOT body will be invalid
            // if we load using the dataSnippet's helper query at compile time.
            fieldClassReg = cg->allocateRegister();
            generateRegMemInstruction(TR::InstOpCode::LEARegMem(), node, fieldClassReg, generateX86MemoryReference(dataSnippet->getSnippetLabel(), cg), cg);
            generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, fieldClassReg, generateX86MemoryReference(fieldClassReg, offsetof(J9JITWatchedStaticFieldData, fieldClass), cg), cg);
            classFlagsMemRef = generateX86MemoryReference(fieldClassReg, fej9->getOffsetOfClassFlags(), cg);
            }
         }
      else
         {
         if (isWrite)
            {
            fieldClassReg = cg->allocateRegister();
            generateRegMemInstruction(TR::InstOpCode::LRegMem(), node, fieldClassReg, generateX86MemoryReference(sideEffectRegister, fej9->getOffsetOfClassFromJavaLangClassField(), cg), cg);
            }
         else
            {
            fieldClassReg = sideEffectRegister;
            }
         classFlagsMemRef = generateX86MemoryReference(fieldClassReg, fej9->getOffsetOfClassFlags(), cg);
         }
      }

   generateMemImmInstruction(TR::InstOpCode::TEST2MemImm2, node, classFlagsMemRef, J9ClassHasWatchedFields, cg);
   generateLabelInstruction(TR::InstOpCode::JNE4, node, fieldReportLabel, cg);

   uint8_t numOfConditions = getNumOfConditionsForReportFieldAccess(node, !node->getSymbolReference()->isUnresolved(), isWrite, isInstanceField, cg);
   TR::RegisterDependencyConditions  *deps =  generateRegisterDependencyConditions(numOfConditions, numOfConditions, cg);
   if (isInstanceField || !isResolved || fieldClassNeedsRelocation)
      {
      deps->addPreCondition(fieldClassReg, TR::RealRegister::NoReg, cg);
      deps->addPostCondition(fieldClassReg, TR::RealRegister::NoReg, cg);
      }

      {
      TR_OutlinedInstructionsGenerator og(fieldReportLabel, node ,cg);
      generateReportFieldAccessOutlinedInstructions(node, endLabel, dataSnippet, isWrite, deps, cg, sideEffectRegister, valueReg);
      og.endOutlinedInstructionSequence();
      }
   deps->stopAddingConditions();
   generateLabelInstruction(TR::InstOpCode::label, node, endLabel, deps, cg);

   if (isInstanceField || (!isResolved && isWrite) || fieldClassNeedsRelocation)
      {
      cg->stopUsingRegister(fieldClassReg);
      }
   }

TR::Register *
J9::X86::TreeEvaluator::generateConcurrentScavengeSequence(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR::Register* object = TR::TreeEvaluator::performHeapLoadWithReadBarrier(node, cg);

   if (!node->getSymbolReference()->isUnresolved() &&
       (node->getSymbolReference()->getSymbol()->getKind() == TR::Symbol::IsShadow) &&
       (node->getSymbolReference()->getCPIndex() >= 0) &&
       (cg->comp()->getMethodHotness()>=scorching))
      {
      int32_t len;
      const char *fieldName = node->getSymbolReference()->getOwningMethod(cg->comp())->fieldSignatureChars(
            node->getSymbolReference()->getCPIndex(), len);

      if (fieldName && strstr(fieldName, "Ljava/lang/String;"))
         {
         generateMemInstruction(TR::InstOpCode::PREFETCHT0, node, generateX86MemoryReference(object, 0, cg), cg);
         }
      }
   return object;
   }

TR::Register *
J9::X86::TreeEvaluator::irdbariEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // For rdbar and wrtbar nodes we first evaluate the children we need to
   // handle the side effects. Then we delegate the evaluation of the remaining
   // children and the load/store operation to the appropriate load/store evaluator.
   TR::Node *sideEffectNode = node->getFirstChild();
   TR::Register *sideEffectRegister = cg->evaluate(sideEffectNode);

   if (cg->comp()->getOption(TR_EnableFieldWatch))
      {
      TR::TreeEvaluator::rdWrtbarHelperForFieldWatch(node, cg, sideEffectRegister, NULL);
      }

   TR::Register *resultReg = NULL;
   // Perform regular load if no rdbar required.
   if (TR::Compiler->om.readBarrierType() == gc_modron_readbar_none)
      {
      resultReg = TR::TreeEvaluator::iloadEvaluator(node, cg);
      }
   else
      {
      if (cg->comp()->useCompressedPointers() &&
          (node->getOpCode().hasSymbolReference() &&
           node->getSymbolReference()->getSymbol()->getDataType() == TR::Address))
         {
         resultReg = TR::TreeEvaluator::generateConcurrentScavengeSequence(node, cg);
         node->setRegister(resultReg);
         }
      }

   // Note: For indirect rdbar nodes, the first child (sideEffectNode) is also used by the
   // load evaluator. The load evaluator will also evaluate+decrement it. In order to avoid double
   // decrementing the node we skip doing it here and let the load evaluator do it.
   return resultReg;
   }

TR::Register *
J9::X86::TreeEvaluator::irdbarEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // For rdbar and wrtbar nodes we first evaluate the children we need to
   // handle the side effects. Then we delegate the evaluation of the remaining
   // children and the load/store operation to the appropriate load/store evaluator.
   TR::Node *sideEffectNode = node->getFirstChild();
   TR::Register * sideEffectRegister = cg->evaluate(sideEffectNode);

   if (cg->comp()->getOption(TR_EnableFieldWatch))
      {
      TR::TreeEvaluator::rdWrtbarHelperForFieldWatch(node, cg, sideEffectRegister, NULL);
      }

   cg->decReferenceCount(sideEffectNode);
   return TR::TreeEvaluator::iloadEvaluator(node, cg);
   }

TR::Register *
J9::X86::TreeEvaluator::ardbarEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // For rdbar and wrtbar nodes we first evaluate the children we need to
   // handle the side effects. Then we delegate the evaluation of the remaining
   // children and the load/store operation to the appropriate load/store evaluator.
   TR::Node *sideEffectNode = node->getFirstChild();
   TR::Register *sideEffectRegister = cg->evaluate(sideEffectNode);

   if (cg->comp()->getOption(TR_EnableFieldWatch))
      {
      TR::TreeEvaluator::rdWrtbarHelperForFieldWatch(node, cg, sideEffectRegister, NULL);
      }

   cg->decReferenceCount(sideEffectNode);
   return TR::TreeEvaluator::aloadEvaluator(node, cg);
   }

TR::Register *
J9::X86::TreeEvaluator::ardbariEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // For rdbar and wrtbar nodes we first evaluate the children we need to
   // handle the side effects. Then we delegate the evaluation of the remaining
   // children and the load/store operation to the appropriate load/store evaluator.
   TR::Register *sideEffectRegister = cg->evaluate(node->getFirstChild());

   if (cg->comp()->getOption(TR_EnableFieldWatch))
      {
      TR::TreeEvaluator::rdWrtbarHelperForFieldWatch(node, cg, sideEffectRegister, NULL);
      }

   TR::Register *resultReg = NULL;
   // Perform regular load if no rdbar required.
   if (TR::Compiler->om.readBarrierType() == gc_modron_readbar_none)
      {
      resultReg = TR::TreeEvaluator::aloadEvaluator(node, cg);
      }
   else
      {
      resultReg = TR::TreeEvaluator::generateConcurrentScavengeSequence(node, cg);
      resultReg->setContainsCollectedReference();
      node->setRegister(resultReg);
      }

   // Note: For indirect rdbar nodes, the first child (sideEffectNode) is also used by the
   // load evaluator. The load evaluator will also evaluate+decrement it. In order to avoid double
   // decrementing the node we skip doing it here and let the load evaluator do it.
   return resultReg;
   }

TR::Register *J9::X86::TreeEvaluator::fwrtbarEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // For rdbar and wrtbar nodes we first evaluate the children we need to
   // handle the side effects. Then we delegate the evaluation of the remaining
   // children and the load/store operation to the appropriate load/store evaluator.
   TR::Register *valueReg = cg->evaluate(node->getFirstChild());
   TR::Node *sideEffectNode = node->getSecondChild();
   TR::Register *sideEffectRegister = cg->evaluate(sideEffectNode);

   if (cg->comp()->getOption(TR_EnableFieldWatch))
      {
      TR::TreeEvaluator::rdWrtbarHelperForFieldWatch(node, cg, sideEffectRegister, valueReg);
      }

   // Note: The reference count for valueReg's node is not decremented here because the
   // store evaluator also uses it and so it will evaluate+decrement it. Thus we must skip decrementing here
   // to avoid double decrementing.
   cg->decReferenceCount(sideEffectNode);
   return TR::TreeEvaluator::floatingPointStoreEvaluator(node, cg);
   }

TR::Register *J9::X86::TreeEvaluator::fwrtbariEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // For rdbar and wrtbar nodes we first evaluate the children we need to
   // handle the side effects. Then we delegate the evaluation of the remaining
   // children and the load/store operation to the appropriate load/store evaluator.
   TR::Register *valueReg = cg->evaluate(node->getSecondChild());
   TR::Node *sideEffectNode = node->getThirdChild();
   TR::Register *sideEffectRegister = cg->evaluate(sideEffectNode);

   if (cg->comp()->getOption(TR_EnableFieldWatch))
      {
      TR::TreeEvaluator::rdWrtbarHelperForFieldWatch(node, cg, sideEffectRegister, valueReg);
      }

   // Note: The reference count for valueReg's node is not decremented here because the
   // store evaluator also uses it and so it will evaluate+decrement it. Thus we must skip decrementing here
   // to avoid double decrementing.
   cg->decReferenceCount(sideEffectNode);
   return TR::TreeEvaluator::floatingPointStoreEvaluator(node, cg);
   }

#ifdef TR_TARGET_32BIT
TR::Register *J9::X86::I386::TreeEvaluator::dwrtbarEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // For rdbar and wrtbar nodes we first evaluate the children we need to
   // handle the side effects. Then we delegate the evaluation of the remaining
   // children and the load/store operation to the appropriate load/store evaluator.
   TR::Register *valueReg = cg->evaluate(node->getFirstChild());
   TR::Node *sideEffectNode = node->getSecondChild();
   TR::Register *sideEffectRegister = cg->evaluate(sideEffectNode);

   if (cg->comp()->getOption(TR_EnableFieldWatch))
      {
      TR::TreeEvaluator::rdWrtbarHelperForFieldWatch(node, cg, sideEffectRegister, valueReg);
      }

   // Note: The reference count for valueReg's node is not decremented here because the
   // store evaluator also uses it and so it will evaluate+decrement it. Thus we must skip decrementing here
   // to avoid double decrementing.
   cg->decReferenceCount(sideEffectNode);
   return TR::TreeEvaluator::dstoreEvaluator(node, cg);
   }

TR::Register *J9::X86::I386::TreeEvaluator::dwrtbariEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // For rdbar and wrtbar nodes we first evaluate the children we need to
   // handle the side effects. Then we delegate the evaluation of the remaining
   // children and the load/store operation to the appropriate load/store evaluator.
   TR::Register *valueReg = cg->evaluate(node->getSecondChild());
   TR::Node *sideEffectNode = node->getThirdChild();
   TR::Register *sideEffectRegister = cg->evaluate(sideEffectNode);

   if (cg->comp()->getOption(TR_EnableFieldWatch))
      {
      TR::TreeEvaluator::rdWrtbarHelperForFieldWatch(node, cg, sideEffectRegister, valueReg);
      }

   // Note: The reference count for valueReg's node is not decremented here because the
   // store evaluator also uses it and so it will evaluate+decrement it. Thus we must skip decrementing here
   // to avoid double decrementing.
   cg->decReferenceCount(sideEffectNode);
   return TR::TreeEvaluator::dstoreEvaluator(node, cg);
   }

TR::Register *J9::X86::I386::TreeEvaluator::integerPairDivEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR::Node     *firstChild   = node->getFirstChild();
   TR::Node     *secondChild  = node->getSecondChild();
   TR::Register *lowRegister  = cg->allocateRegister();
   TR::Register *highRegister = cg->allocateRegister();

   TR::Register *firstRegister = cg->evaluate(firstChild);
   TR::Register *secondRegister = cg->evaluate(secondChild);

   TR::Register *firstHigh = firstRegister->getHighOrder();
   TR::Register *secondHigh = secondRegister->getHighOrder();

   TR::Instruction  *divInstr = NULL;

   TR::RegisterDependencyConditions  *idivDependencies = generateRegisterDependencyConditions((uint8_t)6, 6, cg);
   idivDependencies->addPreCondition(lowRegister, TR::RealRegister::eax, cg);
   idivDependencies->addPreCondition(highRegister, TR::RealRegister::edx, cg);
   idivDependencies->addPostCondition(lowRegister, TR::RealRegister::eax, cg);
   idivDependencies->addPostCondition(highRegister, TR::RealRegister::edx, cg);
   idivDependencies->addPreCondition(firstHigh, TR::RealRegister::NoReg, cg);
   idivDependencies->addPreCondition(secondHigh, TR::RealRegister::NoReg, cg);
   idivDependencies->addPostCondition(firstHigh, TR::RealRegister::NoReg, cg);
   idivDependencies->addPostCondition(secondHigh, TR::RealRegister::NoReg, cg);
   idivDependencies->addPreCondition(firstRegister->getLowOrder(), TR::RealRegister::NoReg, cg);
   idivDependencies->addPreCondition(secondRegister->getLowOrder(), TR::RealRegister::NoReg, cg);
   idivDependencies->addPostCondition(firstRegister->getLowOrder(), TR::RealRegister::NoReg, cg);
   idivDependencies->addPostCondition(secondRegister->getLowOrder(), TR::RealRegister::NoReg, cg);

   TR::LabelSymbol *startLabel = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   TR::LabelSymbol *doneLabel  = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   TR::LabelSymbol *callLabel  = TR::LabelSymbol::create(cg->trHeapMemory(),cg);

   startLabel->setStartInternalControlFlow();
   doneLabel->setEndInternalControlFlow();

   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

   generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, highRegister, secondHigh, cg);
   generateRegRegInstruction(TR::InstOpCode::OR4RegReg, node, highRegister, firstHigh, cg);
   //generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, highRegister, highRegister, cg);
   generateLabelInstruction(TR::InstOpCode::JNE4, node, callLabel, cg);

   generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, lowRegister, firstRegister->getLowOrder(), cg);
   divInstr = generateRegRegInstruction(TR::InstOpCode::DIV4AccReg, node, lowRegister, secondRegister->getLowOrder(), idivDependencies, cg);

   cg->setImplicitExceptionPoint(divInstr);
   divInstr->setNeedsGCMap(0xFF00FFF6);

   TR::RegisterDependencyConditions  *xorDependencies1 = generateRegisterDependencyConditions((uint8_t)2, 2, cg);
   xorDependencies1->addPreCondition(lowRegister, TR::RealRegister::eax, cg);
   xorDependencies1->addPreCondition(highRegister, TR::RealRegister::edx, cg);
   xorDependencies1->addPostCondition(lowRegister, TR::RealRegister::eax, cg);
   xorDependencies1->addPostCondition(highRegister, TR::RealRegister::edx, cg);
   generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, highRegister, highRegister, xorDependencies1, cg);

   generateLabelInstruction(TR::InstOpCode::JMP4, node, doneLabel, cg);

   generateLabelInstruction(TR::InstOpCode::label, node, callLabel, cg);

   TR::RegisterDependencyConditions  *dependencies = generateRegisterDependencyConditions((uint8_t)0, 2, cg);
   dependencies->addPostCondition(lowRegister, TR::RealRegister::eax, cg);
   dependencies->addPostCondition(highRegister, TR::RealRegister::edx, cg);
   J9::IA32PrivateLinkage *linkage = static_cast<J9::IA32PrivateLinkage *>(cg->getLinkage(TR_Private));
   TR::IA32LinkageUtils::pushLongArg(secondChild, cg);
   TR::IA32LinkageUtils::pushLongArg(firstChild, cg);
   TR::X86ImmSymInstruction  *instr =
         generateHelperCallInstruction(node, TR_IA32longDivide, dependencies, cg);
   if (!linkage->getProperties().getCallerCleanup())
      {
      instr->setAdjustsFramePointerBy(-16);  // 2 long args
      }

   // Don't preserve eax and edx
   //
   instr->setNeedsGCMap(0xFF00FFF6);

   TR::RegisterDependencyConditions  *labelDependencies = generateRegisterDependencyConditions((uint8_t)6, 6, cg);
   labelDependencies->addPreCondition(lowRegister, TR::RealRegister::eax, cg);
   labelDependencies->addPreCondition(highRegister, TR::RealRegister::edx, cg);
   labelDependencies->addPostCondition(lowRegister, TR::RealRegister::eax, cg);
   labelDependencies->addPostCondition(highRegister, TR::RealRegister::edx, cg);
   labelDependencies->addPreCondition(firstHigh, TR::RealRegister::NoReg, cg);
   labelDependencies->addPreCondition(secondHigh, TR::RealRegister::NoReg, cg);
   labelDependencies->addPostCondition(firstHigh, TR::RealRegister::NoReg, cg);
   labelDependencies->addPostCondition(secondHigh, TR::RealRegister::NoReg, cg);
   labelDependencies->addPreCondition(firstRegister->getLowOrder(), TR::RealRegister::NoReg, cg);
   labelDependencies->addPreCondition(secondRegister->getLowOrder(), TR::RealRegister::NoReg, cg);
   labelDependencies->addPostCondition(firstRegister->getLowOrder(), TR::RealRegister::NoReg, cg);
   labelDependencies->addPostCondition(secondRegister->getLowOrder(), TR::RealRegister::NoReg, cg);

   generateLabelInstruction(TR::InstOpCode::label, node, doneLabel, labelDependencies, cg);

   TR::Register *targetRegister = cg->allocateRegisterPair(lowRegister, highRegister);
   node->setRegister(targetRegister);

   return targetRegister;
   }

TR::Register *J9::X86::I386::TreeEvaluator::integerPairRemEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // TODO: Consider combining with integerPairDivEvaluator
   TR::Node     *firstChild   = node->getFirstChild();
   TR::Node     *secondChild  = node->getSecondChild();
   TR::Register *lowRegister  = cg->allocateRegister();
   TR::Register *highRegister = cg->allocateRegister();

   TR::Register *firstRegister = cg->evaluate(firstChild);
   TR::Register *secondRegister = cg->evaluate(secondChild);

   TR::Register *firstHigh = firstRegister->getHighOrder();
   TR::Register *secondHigh = secondRegister->getHighOrder();

   TR::Instruction  *divInstr = NULL;

   TR::RegisterDependencyConditions  *idivDependencies = generateRegisterDependencyConditions((uint8_t)6, 6, cg);
   idivDependencies->addPreCondition(lowRegister, TR::RealRegister::eax, cg);
   idivDependencies->addPreCondition(highRegister, TR::RealRegister::edx, cg);
   idivDependencies->addPostCondition(lowRegister, TR::RealRegister::eax, cg);
   idivDependencies->addPostCondition(highRegister, TR::RealRegister::edx, cg);
   idivDependencies->addPreCondition(firstHigh, TR::RealRegister::NoReg, cg);
   idivDependencies->addPreCondition(secondHigh, TR::RealRegister::NoReg, cg);
   idivDependencies->addPostCondition(firstHigh, TR::RealRegister::NoReg, cg);
   idivDependencies->addPostCondition(secondHigh, TR::RealRegister::NoReg, cg);
   idivDependencies->addPreCondition(firstRegister->getLowOrder(), TR::RealRegister::NoReg, cg);
   idivDependencies->addPreCondition(secondRegister->getLowOrder(), TR::RealRegister::NoReg, cg);
   idivDependencies->addPostCondition(firstRegister->getLowOrder(), TR::RealRegister::NoReg, cg);
   idivDependencies->addPostCondition(secondRegister->getLowOrder(), TR::RealRegister::NoReg, cg);

   TR::LabelSymbol *startLabel = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   TR::LabelSymbol *doneLabel  = TR::LabelSymbol::create(cg->trHeapMemory(),cg);
   TR::LabelSymbol *callLabel  = TR::LabelSymbol::create(cg->trHeapMemory(),cg);

   startLabel->setStartInternalControlFlow();
   doneLabel->setEndInternalControlFlow();

   generateLabelInstruction(TR::InstOpCode::label, node, startLabel, cg);

   generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, highRegister, secondHigh, cg);
   generateRegRegInstruction(TR::InstOpCode::OR4RegReg, node, highRegister, firstHigh, cg);
   // it doesn't need the test instruction, OR will set the flags properly
   //generateRegRegInstruction(TR::InstOpCode::TEST4RegReg, node, highRegister, highRegister, cg);
   generateLabelInstruction(TR::InstOpCode::JNE4, node, callLabel, cg);

   generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, lowRegister, firstRegister->getLowOrder(), cg);
   divInstr = generateRegRegInstruction(TR::InstOpCode::DIV4AccReg, node, lowRegister, secondRegister->getLowOrder(), idivDependencies, cg);

   cg->setImplicitExceptionPoint(divInstr);
   divInstr->setNeedsGCMap(0xFF00FFF6);

   generateRegRegInstruction(TR::InstOpCode::MOV4RegReg, node, lowRegister, highRegister, cg);

   generateRegRegInstruction(TR::InstOpCode::XOR4RegReg, node, highRegister, highRegister, cg);
   generateLabelInstruction(TR::InstOpCode::JMP4, node, doneLabel, cg);

   generateLabelInstruction(TR::InstOpCode::label, node, callLabel, cg);

   TR::RegisterDependencyConditions  *dependencies = generateRegisterDependencyConditions((uint8_t)4, 6, cg);

   dependencies->addPostCondition(lowRegister, TR::RealRegister::eax, cg);
   dependencies->addPostCondition(highRegister, TR::RealRegister::edx, cg);
   dependencies->addPreCondition(firstHigh, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(secondHigh, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(firstHigh, TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(secondHigh, TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(firstRegister->getLowOrder(), TR::RealRegister::NoReg, cg);
   dependencies->addPreCondition(secondRegister->getLowOrder(), TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(firstRegister->getLowOrder(), TR::RealRegister::NoReg, cg);
   dependencies->addPostCondition(secondRegister->getLowOrder(), TR::RealRegister::NoReg, cg);

   J9::IA32PrivateLinkage *linkage = static_cast<J9::IA32PrivateLinkage *>(cg->getLinkage(TR_Private));
   TR::IA32LinkageUtils::pushLongArg(secondChild, cg);
   TR::IA32LinkageUtils::pushLongArg(firstChild, cg);
   TR::X86ImmSymInstruction *instr = generateHelperCallInstruction(node, TR_IA32longRemainder, dependencies, cg);
   if (!linkage->getProperties().getCallerCleanup())
      {
      instr->setAdjustsFramePointerBy(-16);  // 2 long args
      }

   // Don't preserve eax and edx
   //
   instr->setNeedsGCMap(0xFF00FFF6);

   TR::RegisterDependencyConditions *movDependencies = generateRegisterDependencyConditions((uint8_t)6, 6, cg);
   movDependencies->addPreCondition(lowRegister, TR::RealRegister::eax, cg);
   movDependencies->addPreCondition(highRegister, TR::RealRegister::edx, cg);
   movDependencies->addPostCondition(lowRegister, TR::RealRegister::eax, cg);
   movDependencies->addPostCondition(highRegister, TR::RealRegister::edx, cg);
   movDependencies->addPreCondition(firstHigh, TR::RealRegister::NoReg, cg);
   movDependencies->addPreCondition(secondHigh, TR::RealRegister::NoReg, cg);
   movDependencies->addPostCondition(firstHigh, TR::RealRegister::NoReg, cg);
   movDependencies->addPostCondition(secondHigh, TR::RealRegister::NoReg, cg);
   movDependencies->addPreCondition(firstRegister->getLowOrder(), TR::RealRegister::NoReg, cg);
   movDependencies->addPreCondition(secondRegister->getLowOrder(), TR::RealRegister::NoReg, cg);
   movDependencies->addPostCondition(firstRegister->getLowOrder(), TR::RealRegister::NoReg, cg);
   movDependencies->addPostCondition(secondRegister->getLowOrder(), TR::RealRegister::NoReg, cg);

   generateLabelInstruction(TR::InstOpCode::label, node, doneLabel, movDependencies, cg);

   TR::Register *targetRegister = cg->allocateRegisterPair(lowRegister, highRegister);
   node->setRegister(targetRegister);

   return targetRegister;
   }

bool J9::X86::I386::TreeEvaluator::lstoreEvaluatorIsNodeVolatile(TR::Node *node, TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR::SymbolReference *symRef = node->getSymbolReference();
   bool isVolatile = false;

   if (symRef && !symRef->isUnresolved())
      {
      TR::Symbol *symbol = symRef->getSymbol();
      isVolatile = symbol->isVolatile();
      TR_OpaqueMethodBlock *caller = node->getOwningMethod();
      if (isVolatile && caller)
         {
         TR_ResolvedMethod *m = comp->fe()->createResolvedMethod(cg->trMemory(), caller, node->getSymbolReference()->getOwningMethod(comp));
         if (m->getRecognizedMethod() == TR::java_util_concurrent_atomic_AtomicLong_lazySet)
            {
            isVolatile = false;
            }
         }
      }

   return isVolatile;
   }

void J9::X86::I386::TreeEvaluator::lStoreEvaluatorSetHighLowMRIfNeeded(TR::Node *node,
                                                                       TR::MemoryReference *lowMR,
                                                                       TR::MemoryReference *highMR,
                                                                       TR::CodeGenerator *cg)
   {
   if (node->getSymbolReference()->getSymbol()->isVolatile())
      {
      TR_OpaqueMethodBlock *caller = node->getOwningMethod();
      if ((lowMR || highMR) && caller)
         {
         TR_ResolvedMethod *m = cg->comp()->fe()->createResolvedMethod(cg->trMemory(), caller, node->getSymbolReference()->getOwningMethod(cg->comp()));
         if (m->getRecognizedMethod() == TR::java_util_concurrent_atomic_AtomicLong_lazySet)
            {
            if (lowMR)
               lowMR->setIgnoreVolatile();
            if (highMR)
               highMR->setIgnoreVolatile();
            }
         }
      }
   }
#endif

#ifdef TR_TARGET_64BIT
TR::Register *J9::X86::AMD64::TreeEvaluator::dwrtbarEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // For rdbar and wrtbar nodes we first evaluate the children we need to
   // handle the side effects. Then we delegate the evaluation of the remaining
   // children and the load/store operation to the appropriate load/store evaluator.
   TR::Register *valueReg = cg->evaluate(node->getFirstChild());
   TR::Node *sideEffectNode = node->getSecondChild();
   TR::Register *sideEffectRegister = cg->evaluate(sideEffectNode);

   if (cg->comp()->getOption(TR_EnableFieldWatch))
      {
      TR::TreeEvaluator::rdWrtbarHelperForFieldWatch(node, cg, sideEffectRegister, valueReg);
      }

   // Note: The reference count for valueReg's node is not decremented here because the
   // store evaluator also uses it and so it will evaluate+decrement it. Thus we must skip decrementing here
   // to avoid double decrementing.
   cg->decReferenceCount(sideEffectNode);
   return TR::TreeEvaluator::floatingPointStoreEvaluator(node, cg);
   }

TR::Register *J9::X86::AMD64::TreeEvaluator::dwrtbariEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // For rdbar and wrtbar nodes we first evaluate the children we need to
   // handle the side effects. Then we delegate the evaluation of the remaining
   // children and the load/store operation to the appropriate load/store evaluator.
   TR::Register *valueReg = cg->evaluate(node->getSecondChild());
   TR::Node *sideEffectNode = node->getThirdChild();
   TR::Register *sideEffectRegister = cg->evaluate(sideEffectNode);

   if (cg->comp()->getOption(TR_EnableFieldWatch))
      {
      TR::TreeEvaluator::rdWrtbarHelperForFieldWatch(node, cg, sideEffectRegister, valueReg);
      }

   // Note: The reference count for valueReg's node is not decremented here because the
   // store evaluator also uses it and so it will evaluate+decrement it. Thus we must skip decrementing here
   // to avoid double decrementing.
   cg->decReferenceCount(sideEffectNode);
   return TR::TreeEvaluator::floatingPointStoreEvaluator(node, cg);
   }
#endif

TR::Register *J9::X86::TreeEvaluator::awrtbariEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   return TR::TreeEvaluator::awrtbarEvaluator(node, cg);
   }

TR::Register *J9::X86::TreeEvaluator::awrtbarEvaluator(TR::Node *node, TR::CodeGenerator *cg)
   {
   // For rdbar and wrtbar nodes we first evaluate the children we need to
   // handle the side effects. Then we delegate the evaluation of the remaining
   // children and the load/store operation to the appropriate load/store evaluator.
   TR::Register *valueReg;
   TR::Register *sideEffectRegister;
   TR::Node *firstChildNode = node->getFirstChild();

   // Evaluate the children we need to handle the side effect, then go to writeBarrierEvaluator to handle the write barrier
   if (node->getOpCode().isIndirect())
      {
      TR::Node *valueNode = NULL;
      // Pass in valueNode so it can be set to the correct node.
      TR::TreeEvaluator::getIndirectWrtbarValueNode(cg, node, valueNode, false);
      valueReg = cg->evaluate(valueNode);
      sideEffectRegister = cg->evaluate(node->getThirdChild());
      }
   else
      {
      valueReg = cg->evaluate(firstChildNode);
      sideEffectRegister = cg->evaluate(node->getSecondChild());
      }

   if (cg->comp()->getOption(TR_EnableFieldWatch) && !node->getSymbolReference()->getSymbol()->isArrayShadowSymbol())
      {
      TR::TreeEvaluator::rdWrtbarHelperForFieldWatch(node, cg, sideEffectRegister, valueReg);
      }

   // This evaluator handles the actual awrtbar operation. We also avoid decrementing the reference
   // counts of the children evaluated here and let this helper handle it.
   return TR::TreeEvaluator::writeBarrierEvaluator(node, cg);
   }
