1 /* 2 * Copyright (c) 2009, 2016, 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 package org.graalvm.compiler.nodes.java; 24 25 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_50; 26 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_100; 27 28 import org.graalvm.compiler.core.common.LocationIdentity; 29 import org.graalvm.compiler.graph.IterableNodeType; 30 import org.graalvm.compiler.graph.NodeClass; 31 import org.graalvm.compiler.nodeinfo.NodeInfo; 32 import org.graalvm.compiler.nodes.ValueNode; 33 import org.graalvm.compiler.nodes.extended.MonitorExit; 34 import org.graalvm.compiler.nodes.memory.MemoryCheckpoint; 35 import org.graalvm.compiler.nodes.spi.Lowerable; 36 import org.graalvm.compiler.nodes.spi.LoweringTool; 37 import org.graalvm.compiler.nodes.spi.Virtualizable; 38 import org.graalvm.compiler.nodes.spi.VirtualizerTool; 39 import org.graalvm.compiler.nodes.virtual.VirtualObjectNode; 40 41 /** 42 * The {@code MonitorExitNode} represents a monitor release. If it is the release of the monitor of 43 * a synchronized method, then the return value of the method will be referenced via the edge 44 * {@link #escapedReturnValue}, so that it will be materialized before releasing the monitor. 45 */ 46 @NodeInfo(cycles = CYCLES_50, size = SIZE_100) 47 public final class MonitorExitNode extends AccessMonitorNode implements Virtualizable, Lowerable, IterableNodeType, MonitorExit, MemoryCheckpoint.Single { 48 49 public static final NodeClass<MonitorExitNode> TYPE = NodeClass.create(MonitorExitNode.class); 50 51 /** 52 * Non-null for the monitor exit introduced due to a synchronized root method and null in all 53 * other cases. 54 */ 55 @OptionalInput ValueNode escapedReturnValue; 56 57 public MonitorExitNode(ValueNode object, MonitorIdNode monitorId, ValueNode escapedReturnValue) { 58 super(TYPE, object, monitorId); 59 this.escapedReturnValue = escapedReturnValue; 60 } 61 62 /** 63 * Return value is cleared when a synchronized method graph is inlined. 64 */ 65 public void clearEscapedReturnValue() { 66 updateUsages(escapedReturnValue, null); 67 this.escapedReturnValue = null; 68 } 69 70 @Override 71 public LocationIdentity getLocationIdentity() { 72 return LocationIdentity.any(); 73 } 74 75 @Override 76 public void lower(LoweringTool tool) { 77 tool.getLowerer().lower(this, tool); 78 } 79 80 @Override 81 public void virtualize(VirtualizerTool tool) { 82 ValueNode alias = tool.getAlias(object()); 83 if (alias instanceof VirtualObjectNode) { 84 VirtualObjectNode virtual = (VirtualObjectNode) alias; 85 if (virtual.hasIdentity()) { 86 MonitorIdNode removedLock = tool.removeLock(virtual); 87 assert removedLock == getMonitorId() : "mismatch at " + this + ": " + removedLock + " vs. " + getMonitorId(); 88 tool.delete(); 89 } 90 } 91 } 92 }