001/*
002 * Copyright (c) 2011, 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.memory;
024
025import jdk.internal.jvmci.meta.*;
026
027import com.oracle.graal.compiler.common.type.*;
028import com.oracle.graal.graph.*;
029import com.oracle.graal.nodeinfo.*;
030import com.oracle.graal.nodes.*;
031import com.oracle.graal.nodes.extended.*;
032import com.oracle.graal.nodes.memory.address.*;
033
034@NodeInfo(allowedUsageTypes = {InputType.Memory})
035public abstract class AbstractWriteNode extends FixedAccessNode implements StateSplit, MemoryCheckpoint.Single, MemoryAccess, GuardingNode {
036
037    public static final NodeClass<AbstractWriteNode> TYPE = NodeClass.create(AbstractWriteNode.class);
038    @Input ValueNode value;
039    @OptionalInput(InputType.State) FrameState stateAfter;
040    @OptionalInput(InputType.Memory) Node lastLocationAccess;
041
042    protected final boolean initialization;
043
044    public FrameState stateAfter() {
045        return stateAfter;
046    }
047
048    public void setStateAfter(FrameState x) {
049        assert x == null || x.isAlive() : "frame state must be in a graph";
050        updateUsages(stateAfter, x);
051        stateAfter = x;
052    }
053
054    public boolean hasSideEffect() {
055        return true;
056    }
057
058    public ValueNode value() {
059        return value;
060    }
061
062    /**
063     * Returns whether this write is the initialization of the written location. If it is true, the
064     * old value of the memory location is either uninitialized or zero. If it is false, the memory
065     * location is guaranteed to contain a valid value or zero.
066     */
067    public boolean isInitialization() {
068        return initialization;
069    }
070
071    protected AbstractWriteNode(NodeClass<? extends AbstractWriteNode> c, AddressNode address, LocationIdentity location, ValueNode value, BarrierType barrierType) {
072        this(c, address, location, value, barrierType, false);
073    }
074
075    protected AbstractWriteNode(NodeClass<? extends AbstractWriteNode> c, AddressNode address, LocationIdentity location, ValueNode value, BarrierType barrierType, boolean initialization) {
076        super(c, address, location, StampFactory.forVoid(), barrierType);
077        this.value = value;
078        this.initialization = initialization;
079    }
080
081    protected AbstractWriteNode(NodeClass<? extends AbstractWriteNode> c, AddressNode address, LocationIdentity location, ValueNode value, BarrierType barrierType, GuardingNode guard,
082                    boolean initialization) {
083        super(c, address, location, StampFactory.forVoid(), guard, barrierType, false, null);
084        this.value = value;
085        this.initialization = initialization;
086    }
087
088    @Override
089    public boolean isAllowedUsageType(InputType type) {
090        return (type == InputType.Guard && getNullCheck()) ? true : super.isAllowedUsageType(type);
091    }
092
093    public MemoryNode getLastLocationAccess() {
094        return (MemoryNode) lastLocationAccess;
095    }
096
097    public void setLastLocationAccess(MemoryNode lla) {
098        Node newLla = ValueNodeUtil.asNode(lla);
099        updateUsages(lastLocationAccess, newLla);
100        lastLocationAccess = newLla;
101    }
102}