/*[INCLUDE-IF (JAVA_SPEC_VERSION >= 9) & !OPENJDK_METHODHANDLES]*/
/*
 * Copyright IBM Corp. and others 2016
 *
 * 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
 */
package java.lang.invoke;

import java.lang.invoke.VarHandle.AccessMode;

/**
 * Base class for VarHandleInvokers.
 *
 * Invokers are the MethodHandle-subclasses required to implement
 * the invokeExact and invoke MethodHandle combinators.
 */
@VMCONSTANTPOOL_CLASS
abstract class VarHandleInvokeHandle extends PrimitiveHandle {
	@VMCONSTANTPOOL_FIELD
	final int operation;
	@VMCONSTANTPOOL_FIELD
	final MethodType accessModeType;

	VarHandleInvokeHandle(AccessMode accessMode, MethodType accessModeType, byte kind) {
		/* Prepend a VarHandle receiver argument to match the how this MethodHandle will be invoked
		 * Note: the modifiers are specific to the access mode methods in VarHandle.
		 */
		super(accessModeType.insertParameterTypes(0, VarHandle.class), VarHandle.class, accessMode.methodName(), kind, PUBLIC_FINAL_NATIVE, null);
		this.operation = accessMode.ordinal();
		// Append a VarHandle argument to match the VarHandle's internal method signature
		this.accessModeType = accessModeType.appendParameterTypes(VarHandle.class);
	}

	VarHandleInvokeHandle(VarHandleInvokeHandle originalHandle, MethodType newType) {
		super(originalHandle, newType);
		operation = originalHandle.operation;
		accessModeType = originalHandle.accessModeType;
	}

	final void compareWithVarHandleInvoke(VarHandleInvokeHandle left, Comparator c) {
		c.compareStructuralParameter(left.operation, this.operation);
		c.compareStructuralParameter(left.accessModeType, this.accessModeType);
	}

	// {{{ JIT support
	@Override
	protected final ThunkTuple computeThunks(Object arg) {
		return thunkTable().get(new ThunkKey(ThunkKey.computeThunkableType(type(), 0, 1)));
	}
	// }}} JIT support
}
