001/*
002 * Copyright (c) 2012, 2014, 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.hotspot.nodes;
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.calc.*;
031import com.oracle.graal.nodes.spi.*;
032import com.oracle.graal.word.*;
033
034/**
035 * Converts a compile-time constant Java string into a C string installed with the generated code.
036 */
037@NodeInfo
038public final class CStringNode extends FloatingNode implements LIRLowerable {
039
040    public static final NodeClass<CStringNode> TYPE = NodeClass.create(CStringNode.class);
041    protected final String string;
042
043    public CStringNode(@InjectedNodeParameter WordTypes wordTypes, String string) {
044        super(TYPE, StampFactory.forKind(wordTypes.getWordKind()));
045        this.string = string;
046    }
047
048    public void generate(NodeLIRBuilderTool gen) {
049        gen.setResult(this, emitCString(gen, string));
050    }
051
052    public static AllocatableValue emitCString(NodeLIRBuilderTool gen, String value) {
053        AllocatableValue dst = gen.getLIRGeneratorTool().newVariable(LIRKind.value(gen.getLIRGeneratorTool().target().wordKind));
054        gen.getLIRGeneratorTool().emitData(dst, toCString(value));
055        return dst;
056    }
057
058    /**
059     * Converts a string to a null terminated byte array of ASCII characters.
060     *
061     * @param s a String that must only contain ASCII characters
062     */
063    public static byte[] toCString(String s) {
064        byte[] bytes = new byte[s.length() + 1];
065        for (int i = 0; i < s.length(); i++) {
066            assert s.charAt(i) < 128 : "non-ascii string: " + s;
067            bytes[i] = (byte) s.charAt(i);
068        }
069        bytes[s.length()] = 0;
070        return bytes;
071    }
072
073    @NodeIntrinsic
074    public static native Word cstring(@ConstantNodeParameter String string);
075}