001/*
002 * Copyright (c) 2010, 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.lir;
024
025import jdk.internal.jvmci.code.*;
026import jdk.internal.jvmci.meta.*;
027
028/**
029 * Represents a value that is yet to be bound to a machine location (such as a {@link RegisterValue}
030 * or {@link StackSlot}) by a register allocator.
031 */
032public final class Variable extends AllocatableValue {
033
034    /**
035     * The identifier of the variable. This is a non-zero index in a contiguous 0-based name space.
036     */
037    public final int index;
038
039    private String name;
040
041    /**
042     * Creates a new variable.
043     *
044     * @param kind
045     * @param index
046     */
047    public Variable(LIRKind kind, int index) {
048        super(kind);
049        assert index >= 0;
050        this.index = index;
051    }
052
053    public void setName(String name) {
054        this.name = name;
055    }
056
057    public String getName() {
058        return name;
059    }
060
061    @Override
062    public String toString() {
063        if (name != null) {
064            return name;
065        } else {
066            return "v" + index + getKindSuffix();
067        }
068    }
069
070    @Override
071    public int hashCode() {
072        return 71 * super.hashCode() + index;
073    }
074
075    @Override
076    public boolean equals(Object obj) {
077        if (obj instanceof Variable) {
078            Variable other = (Variable) obj;
079            return super.equals(other) && index == other.index;
080        }
081        return false;
082    }
083}