/*******************************************************************************
 * 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 <vector>
#include "compile/Compilation.hpp"
#include "cs2/sparsrbit.h"
#include "il/Node.hpp"
#include "il/SymbolReference.hpp"
#include "il/TreeTop.hpp"

#ifndef REMAT_SAFETY_TOOLS
#define REMAT_SAFETY_TOOLS

class RematSafetyInformation {
    std::vector<TR::SparseBitVector, TR::typed_allocator<TR::SparseBitVector, TR::Allocator> > dependentSymRefs;
    std::vector<TR::TreeTop *, TR::typed_allocator<TR::TreeTop *, TR::Allocator> > argumentTreeTops;
    std::vector<TR::TreeTop *, TR::typed_allocator<TR::TreeTop *, TR::Allocator> > rematTreeTops;
    TR::Compilation *comp;

public:
    RematSafetyInformation(TR::Compilation *comp)
        : dependentSymRefs(getTypedAllocator<TR::SparseBitVector>(comp->allocator()))
        , argumentTreeTops(getTypedAllocator<TR::TreeTop *>(comp->allocator()))
        , rematTreeTops(getTypedAllocator<TR::TreeTop *>(comp->allocator()))
        , comp(comp)
    {}

    void add(TR::TreeTop *argStore, TR::SparseBitVector &symRefDependencies);
    void add(TR::TreeTop *argStore, TR::TreeTop *rematStore);

    uint32_t size() { return static_cast<uint32_t>(dependentSymRefs.size()); }

    TR::SparseBitVector &symRefDependencies(uint32_t idx) { return dependentSymRefs[idx]; }

    TR::TreeTop *argStore(uint32_t idx) { return argumentTreeTops[idx]; }

    TR::TreeTop *rematTreeTop(uint32_t idx) { return rematTreeTops[idx]; }

    void dumpInfo(TR::Compilation *comp);
};

class RematTools {
    static TR_YesNoMaybe gatherNodesToCheck(TR::Compilation *comp, TR::Node *privArg, TR::Node *currentNode,
        TR::SparseBitVector &scanTargets, TR::SparseBitVector &symRefsToCheck, bool trace,
        TR::SparseBitVector &visitedNodes);
    static void walkNodesCalculatingRematSafety(TR::Compilation *comp, TR::Node *currentNode,
        TR::SparseBitVector &scanTargets, TR::SparseBitVector &enabledSymRefs, TR::SparseBitVector &unsafeSymRefs,
        bool trace, TR::SparseBitVector &visitedNodes);
    static bool getNextTreeTop(TR::TreeTop *&start, TR_BitVector *blocksToFollow, TR::Block *startBlock);

public:
    static TR_YesNoMaybe gatherNodesToCheck(TR::Compilation *comp, TR::Node *privArg, TR::Node *currentNode,
        TR::SparseBitVector &scanTargets, TR::SparseBitVector &symRefsToCheck, bool trace);

    static bool walkTreesCalculatingRematSafety(TR::Compilation *comp, TR::TreeTop *start, TR::TreeTop *end,
        TR::SparseBitVector &scanTargets, TR::SparseBitVector &unsafeSymRefs, TR_BitVector *blocksToVisit, bool trace);
    static void walkTreesCalculatingRematSafety(TR::Compilation *comp, TR::TreeTop *start, TR::TreeTop *end,
        TR::SparseBitVector &scanTargets, TR::SparseBitVector &unsafeSymRefs, bool trace);

    static bool walkTreeTopsCalculatingRematFailureAlternatives(TR::Compilation *comp, TR::TreeTop *start,
        TR::TreeTop *end, TR::list<TR::TreeTop *> &failedArgs, TR::SparseBitVector &scanTargets,
        RematSafetyInformation &rematInfo, TR_BitVector *blocksToVisit, bool trace);
    static void walkTreeTopsCalculatingRematFailureAlternatives(TR::Compilation *comp, TR::TreeTop *start,
        TR::TreeTop *end, TR::list<TR::TreeTop *> &failedArgs, TR::SparseBitVector &scanTargets,
        RematSafetyInformation &rematInfo, bool trace);
};
#endif
