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.extended;
024
025import jdk.internal.jvmci.meta.*;
026
027import com.oracle.graal.compiler.common.type.*;
028import com.oracle.graal.graph.*;
029import com.oracle.graal.graph.spi.*;
030import com.oracle.graal.nodeinfo.*;
031import com.oracle.graal.nodes.memory.*;
032import com.oracle.graal.nodes.memory.address.*;
033import com.oracle.graal.nodes.spi.*;
034
035/**
036 * Read a raw memory location according to Java field or array read semantics. It will perform read
037 * barriers, implicit conversions and optionally oop uncompression.
038 */
039@NodeInfo(nameTemplate = "JavaRead#{p#location/s}")
040public final class JavaReadNode extends FixedAccessNode implements Lowerable, GuardingNode, Canonicalizable {
041
042    public static final NodeClass<JavaReadNode> TYPE = NodeClass.create(JavaReadNode.class);
043    protected final Kind readKind;
044    protected final boolean compressible;
045
046    public JavaReadNode(Kind readKind, AddressNode address, LocationIdentity location, BarrierType barrierType, boolean compressible) {
047        super(TYPE, address, location, StampFactory.forKind(readKind), barrierType);
048        this.readKind = readKind;
049        this.compressible = compressible;
050    }
051
052    public void lower(LoweringTool tool) {
053        tool.getLowerer().lower(this, tool);
054    }
055
056    public boolean canNullCheck() {
057        return true;
058    }
059
060    public Kind getReadKind() {
061        return readKind;
062    }
063
064    public boolean isCompressible() {
065        return compressible;
066    }
067
068    @Override
069    public Node canonical(CanonicalizerTool tool) {
070        return ReadNode.canonicalizeRead(this, getAddress(), getLocationIdentity(), tool);
071    }
072}