1 /* 2 * Copyright (c) 2009, 2019, 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 static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_64; 28 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_64; 29 30 import org.graalvm.compiler.graph.IterableNodeType; 31 import org.graalvm.compiler.graph.NodeClass; 32 import org.graalvm.compiler.nodeinfo.NodeInfo; 33 import org.graalvm.compiler.nodes.ValueNode; 34 import org.graalvm.compiler.nodes.extended.MonitorExit; 35 import org.graalvm.compiler.nodes.memory.MemoryCheckpoint; 36 import org.graalvm.compiler.nodes.spi.Lowerable; 37 import org.graalvm.compiler.nodes.spi.LoweringTool; 38 import org.graalvm.compiler.nodes.spi.Virtualizable; 39 import org.graalvm.compiler.nodes.spi.VirtualizerTool; 40 import org.graalvm.compiler.nodes.virtual.VirtualObjectNode; 41 import jdk.internal.vm.compiler.word.LocationIdentity; 42 43 /** 44 * The {@code MonitorExitNode} represents a monitor release. If it is the release of the monitor of 45 * a synchronized method, then the return value of the method will be referenced via the edge 46 * {@link #escapedReturnValue}, so that it will be materialized before releasing the monitor. 47 */ 48 @NodeInfo(cycles = CYCLES_64, size = SIZE_64) 49 public final class MonitorExitNode extends AccessMonitorNode implements Virtualizable, Lowerable, IterableNodeType, MonitorExit, MemoryCheckpoint.Single { 50 51 public static final NodeClass<MonitorExitNode> TYPE = NodeClass.create(MonitorExitNode.class); 52 53 /** 54 * Non-null for the monitor exit introduced due to a synchronized root method and null in all 55 * other cases. 56 */ 57 @OptionalInput ValueNode escapedReturnValue; 58 MonitorExitNode(ValueNode object, MonitorIdNode monitorId, ValueNode escapedValue)59 public MonitorExitNode(ValueNode object, MonitorIdNode monitorId, ValueNode escapedValue) { 60 super(TYPE, object, monitorId); 61 this.escapedReturnValue = escapedValue; 62 } 63 64 /** 65 * Return value is cleared when a synchronized method graph is inlined. 66 */ clearEscapedValue()67 public void clearEscapedValue() { 68 updateUsages(escapedReturnValue, null); 69 this.escapedReturnValue = null; 70 } 71 72 @Override getKilledLocationIdentity()73 public LocationIdentity getKilledLocationIdentity() { 74 return LocationIdentity.any(); 75 } 76 77 @Override lower(LoweringTool tool)78 public void lower(LoweringTool tool) { 79 tool.getLowerer().lower(this, tool); 80 } 81 82 @Override virtualize(VirtualizerTool tool)83 public void virtualize(VirtualizerTool tool) { 84 ValueNode alias = tool.getAlias(object()); 85 if (alias instanceof VirtualObjectNode) { 86 VirtualObjectNode virtual = (VirtualObjectNode) alias; 87 if (virtual.hasIdentity()) { 88 MonitorIdNode removedLock = tool.removeLock(virtual); 89 assert removedLock == getMonitorId() : "mismatch at " + this + ": " + removedLock + " vs. " + getMonitorId(); 90 tool.delete(); 91 } 92 } 93 } 94 } 95