1 /* 2 * Copyright (c) 2011, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 25 package org.graalvm.compiler.nodes.java; 26 27 import org.graalvm.compiler.core.common.type.StampFactory; 28 import org.graalvm.compiler.graph.NodeClass; 29 import org.graalvm.compiler.nodeinfo.NodeInfo; 30 import org.graalvm.compiler.nodes.ConstantNode; 31 import org.graalvm.compiler.nodes.LogicNode; 32 import org.graalvm.compiler.nodes.NodeView; 33 import org.graalvm.compiler.nodes.ValueNode; 34 import org.graalvm.compiler.nodes.calc.ConditionalNode; 35 import org.graalvm.compiler.nodes.spi.VirtualizerTool; 36 import jdk.internal.vm.compiler.word.LocationIdentity; 37 38 import jdk.vm.ci.meta.JavaKind; 39 40 /** 41 * Represents an atomic compare-and-swap operation. The result is a boolean that contains whether 42 * the value matched the expected value. 43 */ 44 @NodeInfo 45 public final class UnsafeCompareAndSwapNode extends AbstractUnsafeCompareAndSwapNode { 46 47 public static final NodeClass<UnsafeCompareAndSwapNode> TYPE = NodeClass.create(UnsafeCompareAndSwapNode.class); 48 49 public UnsafeCompareAndSwapNode(ValueNode object, ValueNode offset, ValueNode expected, ValueNode newValue, JavaKind valueKind, LocationIdentity locationIdentity) { 50 super(TYPE, StampFactory.forKind(JavaKind.Boolean.getStackKind()), object, offset, expected, newValue, valueKind, locationIdentity); 51 assert expected.stamp(NodeView.DEFAULT).isCompatible(newValue.stamp(NodeView.DEFAULT)); 52 } 53 54 @Override 55 protected void finishVirtualize(VirtualizerTool tool, LogicNode equalsNode, ValueNode currentValue) { 56 ValueNode result = ConditionalNode.create(equalsNode, ConstantNode.forBoolean(true, graph()), ConstantNode.forBoolean(false, graph()), NodeView.DEFAULT); 57 if (!result.isAlive()) { 58 tool.addNode(result); 59 } 60 tool.replaceWith(result); 61 } 62 }