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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package org.graalvm.compiler.nodes.java;

import static org.graalvm.compiler.nodeinfo.InputType.Memory;
import static org.graalvm.compiler.nodeinfo.InputType.State;

import org.graalvm.compiler.core.common.type.Stamp;
import org.graalvm.compiler.graph.NodeClass;
import org.graalvm.compiler.nodeinfo.InputType;
import org.graalvm.compiler.nodeinfo.NodeInfo;
import org.graalvm.compiler.nodes.FrameState;
import org.graalvm.compiler.nodes.NodeView;
import org.graalvm.compiler.nodes.StateSplit;
import org.graalvm.compiler.nodes.ValueNode;
import org.graalvm.compiler.nodes.memory.FixedAccessNode;
import org.graalvm.compiler.nodes.memory.LIRLowerableAccess;
import org.graalvm.compiler.nodes.memory.MemoryCheckpoint;
import org.graalvm.compiler.nodes.memory.address.AddressNode;
import jdk.internal.vm.compiler.word.LocationIdentity;

Low-level atomic compare-and-swap operation.
/** * Low-level atomic compare-and-swap operation. */
@NodeInfo(allowedUsageTypes = {InputType.Value, Memory}) public abstract class AbstractCompareAndSwapNode extends FixedAccessNode implements StateSplit, LIRLowerableAccess, MemoryCheckpoint.Single { public static final NodeClass<AbstractCompareAndSwapNode> TYPE = NodeClass.create(AbstractCompareAndSwapNode.class); @Input ValueNode expectedValue; @Input ValueNode newValue; @OptionalInput(State) FrameState stateAfter; @Override public FrameState stateAfter() { return stateAfter; } @Override public void setStateAfter(FrameState x) { assert x == null || x.isAlive() : "frame state must be in a graph"; updateUsages(stateAfter, x); stateAfter = x; } @Override public boolean hasSideEffect() { return true; } public ValueNode getExpectedValue() { return expectedValue; } public ValueNode getNewValue() { return newValue; } public AbstractCompareAndSwapNode(NodeClass<? extends AbstractCompareAndSwapNode> c, AddressNode address, LocationIdentity location, ValueNode expectedValue, ValueNode newValue, BarrierType barrierType, Stamp stamp) { super(c, address, location, stamp, barrierType); assert expectedValue.getStackKind() == newValue.getStackKind(); this.expectedValue = expectedValue; this.newValue = newValue; } @Override public boolean canNullCheck() { return false; } @Override public Stamp getAccessStamp() { return expectedValue.stamp(NodeView.DEFAULT).meet(newValue.stamp(NodeView.DEFAULT)).unrestricted(); } }