/*
* Copyright (c) 2009, 2018, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* 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).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package org.graalvm.compiler.nodes.java;
import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_64;
import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_64;
import org.graalvm.compiler.graph.IterableNodeType;
import org.graalvm.compiler.graph.NodeClass;
import org.graalvm.compiler.nodeinfo.NodeInfo;
import org.graalvm.compiler.nodes.ValueNode;
import org.graalvm.compiler.nodes.extended.MonitorExit;
import org.graalvm.compiler.nodes.memory.MemoryCheckpoint;
import org.graalvm.compiler.nodes.spi.Lowerable;
import org.graalvm.compiler.nodes.spi.LoweringTool;
import org.graalvm.compiler.nodes.spi.Virtualizable;
import org.graalvm.compiler.nodes.spi.VirtualizerTool;
import org.graalvm.compiler.nodes.virtual.VirtualObjectNode;
import jdk.internal.vm.compiler.word.LocationIdentity;
The MonitorExitNode
represents a monitor release. If it is the release of the monitor of a synchronized method, then the return value of the method will be referenced via the edge escapedReturnValue
, so that it will be materialized before releasing the monitor. /**
* The {@code MonitorExitNode} represents a monitor release. If it is the release of the monitor of
* a synchronized method, then the return value of the method will be referenced via the edge
* {@link #escapedReturnValue}, so that it will be materialized before releasing the monitor.
*/
@NodeInfo(cycles = CYCLES_64, size = SIZE_64)
public final class MonitorExitNode extends AccessMonitorNode implements Virtualizable, Lowerable, IterableNodeType, MonitorExit, MemoryCheckpoint.Single {
public static final NodeClass<MonitorExitNode> TYPE = NodeClass.create(MonitorExitNode.class);
Non-null for the monitor exit introduced due to a synchronized root method and null in all
other cases.
/**
* Non-null for the monitor exit introduced due to a synchronized root method and null in all
* other cases.
*/
@OptionalInput ValueNode escapedReturnValue;
public MonitorExitNode(ValueNode object, MonitorIdNode monitorId, ValueNode escapedReturnValue) {
super(TYPE, object, monitorId);
this.escapedReturnValue = escapedReturnValue;
}
Return value is cleared when a synchronized method graph is inlined.
/**
* Return value is cleared when a synchronized method graph is inlined.
*/
public void clearEscapedReturnValue() {
updateUsages(escapedReturnValue, null);
this.escapedReturnValue = null;
}
@Override
public LocationIdentity getLocationIdentity() {
return LocationIdentity.any();
}
@Override
public void lower(LoweringTool tool) {
tool.getLowerer().lower(this, tool);
}
@Override
public void virtualize(VirtualizerTool tool) {
ValueNode alias = tool.getAlias(object());
if (alias instanceof VirtualObjectNode) {
VirtualObjectNode virtual = (VirtualObjectNode) alias;
if (virtual.hasIdentity()) {
MonitorIdNode removedLock = tool.removeLock(virtual);
assert removedLock == getMonitorId() : "mismatch at " + this + ": " + removedLock + " vs. " + getMonitorId();
tool.delete();
}
}
}
}