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package org.graalvm.compiler.nodes.java;

import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_8;
import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_8;

import org.graalvm.compiler.graph.NodeClass;
import org.graalvm.compiler.lir.gen.LIRGeneratorTool;
import org.graalvm.compiler.nodeinfo.NodeInfo;
import org.graalvm.compiler.nodes.NodeView;
import org.graalvm.compiler.nodes.ValueNode;
import org.graalvm.compiler.nodes.memory.address.AddressNode;
import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool;
import jdk.internal.vm.compiler.word.LocationIdentity;

A special purpose store node that differs from LogicCompareAndSwapNode in that it returns either the expected value or the compared against value instead of a boolean.
/** * A special purpose store node that differs from {@link LogicCompareAndSwapNode} in that it returns * either the expected value or the compared against value instead of a boolean. */
@NodeInfo(cycles = CYCLES_8, size = SIZE_8) public final class ValueCompareAndSwapNode extends AbstractCompareAndSwapNode { public static final NodeClass<ValueCompareAndSwapNode> TYPE = NodeClass.create(ValueCompareAndSwapNode.class); public ValueCompareAndSwapNode(ValueNode address, ValueNode expectedValue, ValueNode newValue, LocationIdentity location) { this((AddressNode) address, expectedValue, newValue, location, BarrierType.NONE); } public ValueCompareAndSwapNode(AddressNode address, ValueNode expectedValue, ValueNode newValue, LocationIdentity location, BarrierType barrierType) { super(TYPE, address, location, expectedValue, newValue, barrierType, expectedValue.stamp(NodeView.DEFAULT).meet(newValue.stamp(NodeView.DEFAULT)).unrestricted()); } @Override public void generate(NodeLIRBuilderTool gen) { assert getNewValue().stamp(NodeView.DEFAULT).isCompatible(getExpectedValue().stamp(NodeView.DEFAULT)); LIRGeneratorTool tool = gen.getLIRGeneratorTool(); assert !this.canDeoptimize(); gen.setResult(this, tool.emitValueCompareAndSwap(tool.getLIRKind(getAccessStamp()), gen.operand(getAddress()), gen.operand(getExpectedValue()), gen.operand(getNewValue()))); } }