1/*
2 * Copyright (c) 2014, 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 */
23package org.graalvm.compiler.nodes.java;
24
25import static org.graalvm.compiler.nodeinfo.InputType.Memory;
26import static org.graalvm.compiler.nodeinfo.InputType.State;
27import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_8;
28import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_2;
29
30import org.graalvm.compiler.core.common.LocationIdentity;
31import org.graalvm.compiler.graph.NodeClass;
32import org.graalvm.compiler.nodeinfo.NodeInfo;
33import org.graalvm.compiler.nodes.FrameState;
34import org.graalvm.compiler.nodes.StateSplit;
35import org.graalvm.compiler.nodes.ValueNode;
36import org.graalvm.compiler.nodes.memory.FixedAccessNode;
37import org.graalvm.compiler.nodes.memory.MemoryCheckpoint;
38import org.graalvm.compiler.nodes.memory.address.AddressNode;
39import org.graalvm.compiler.nodes.spi.LIRLowerable;
40import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool;
41
42import jdk.vm.ci.meta.Value;
43import sun.misc.Unsafe;
44
45/**
46 * Represents the lowered version of an atomic read-and-write operation like
47 * {@link Unsafe#getAndSetInt(Object, long, int)} .
48 */
49@NodeInfo(allowedUsageTypes = {Memory}, cycles = CYCLES_8, size = SIZE_2)
50public final class LoweredAtomicReadAndWriteNode extends FixedAccessNode implements StateSplit, LIRLowerable, MemoryCheckpoint.Single {
51
52    public static final NodeClass<LoweredAtomicReadAndWriteNode> TYPE = NodeClass.create(LoweredAtomicReadAndWriteNode.class);
53    @Input ValueNode newValue;
54    @OptionalInput(State) FrameState stateAfter;
55
56    public LoweredAtomicReadAndWriteNode(AddressNode address, LocationIdentity location, ValueNode newValue, BarrierType barrierType) {
57        super(TYPE, address, location, newValue.stamp().unrestricted(), barrierType);
58        this.newValue = newValue;
59    }
60
61    @Override
62    public FrameState stateAfter() {
63        return stateAfter;
64    }
65
66    @Override
67    public void setStateAfter(FrameState x) {
68        assert x == null || x.isAlive() : "frame state must be in a graph";
69        updateUsages(stateAfter, x);
70        stateAfter = x;
71    }
72
73    @Override
74    public boolean hasSideEffect() {
75        return true;
76    }
77
78    @Override
79    public void generate(NodeLIRBuilderTool gen) {
80        Value result = gen.getLIRGeneratorTool().emitAtomicReadAndWrite(gen.operand(getAddress()), gen.operand(getNewValue()));
81        gen.setResult(this, result);
82    }
83
84    @Override
85    public boolean canNullCheck() {
86        return false;
87    }
88
89    public ValueNode getNewValue() {
90        return newValue;
91    }
92}
93