001/*
002 * Copyright (c) 2014, 2015, Oracle and/or its affiliates. All rights reserved.
003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004 *
005 * This code is free software; you can redistribute it and/or modify it
006 * under the terms of the GNU General Public License version 2 only, as
007 * published by the Free Software Foundation.
008 *
009 * This code is distributed in the hope that it will be useful, but WITHOUT
010 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
011 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
012 * version 2 for more details (a copy is included in the LICENSE file that
013 * accompanied this code).
014 *
015 * You should have received a copy of the GNU General Public License version
016 * 2 along with this work; if not, write to the Free Software Foundation,
017 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
018 *
019 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
020 * or visit www.oracle.com if you need additional information or have any
021 * questions.
022 */
023package com.oracle.graal.nodes.java;
024
025import jdk.internal.jvmci.meta.*;
026import sun.misc.*;
027
028import com.oracle.graal.graph.*;
029import com.oracle.graal.nodeinfo.*;
030import com.oracle.graal.nodes.*;
031import com.oracle.graal.nodes.memory.*;
032import com.oracle.graal.nodes.memory.address.*;
033import com.oracle.graal.nodes.spi.*;
034
035/**
036 * Represents the lowered version of an atomic read-and-write operation like
037 * {@link Unsafe#getAndSetInt(Object, long, int)} .
038 */
039@NodeInfo(allowedUsageTypes = {InputType.Memory})
040public final class LoweredAtomicReadAndWriteNode extends FixedAccessNode implements StateSplit, LIRLowerable, MemoryCheckpoint.Single {
041
042    public static final NodeClass<LoweredAtomicReadAndWriteNode> TYPE = NodeClass.create(LoweredAtomicReadAndWriteNode.class);
043    @Input ValueNode newValue;
044    @OptionalInput(InputType.State) FrameState stateAfter;
045
046    public LoweredAtomicReadAndWriteNode(AddressNode address, LocationIdentity location, ValueNode newValue, BarrierType barrierType) {
047        super(TYPE, address, location, newValue.stamp().unrestricted(), barrierType);
048        this.newValue = newValue;
049    }
050
051    public FrameState stateAfter() {
052        return stateAfter;
053    }
054
055    public void setStateAfter(FrameState x) {
056        assert x == null || x.isAlive() : "frame state must be in a graph";
057        updateUsages(stateAfter, x);
058        stateAfter = x;
059    }
060
061    public boolean hasSideEffect() {
062        return true;
063    }
064
065    public void generate(NodeLIRBuilderTool gen) {
066        Value result = gen.getLIRGeneratorTool().emitAtomicReadAndWrite(gen.operand(getAddress()), gen.operand(getNewValue()));
067        gen.setResult(this, result);
068    }
069
070    public boolean canNullCheck() {
071        return false;
072    }
073
074    public ValueNode getNewValue() {
075        return newValue;
076    }
077}