ArrayEqualsNode.java revision 12651:6ef01bd40ce2 
1/*
2 * Copyright (c) 2013, 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.replacements.nodes;
24
25import static org.graalvm.compiler.nodeinfo.InputType.Memory;
26import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_100;
27import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_50;
28
29import org.graalvm.compiler.core.common.LocationIdentity;
30import org.graalvm.compiler.core.common.type.StampFactory;
31import org.graalvm.compiler.graph.Node;
32import org.graalvm.compiler.graph.NodeClass;
33import org.graalvm.compiler.graph.spi.Canonicalizable;
34import org.graalvm.compiler.graph.spi.CanonicalizerTool;
35import org.graalvm.compiler.nodeinfo.NodeInfo;
36import org.graalvm.compiler.nodes.ConstantNode;
37import org.graalvm.compiler.nodes.FixedWithNextNode;
38import org.graalvm.compiler.nodes.NamedLocationIdentity;
39import org.graalvm.compiler.nodes.ValueNode;
40import org.graalvm.compiler.nodes.ValueNodeUtil;
41import org.graalvm.compiler.nodes.memory.MemoryAccess;
42import org.graalvm.compiler.nodes.memory.MemoryNode;
43import org.graalvm.compiler.nodes.spi.LIRLowerable;
44import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool;
45import org.graalvm.compiler.nodes.spi.Virtualizable;
46import org.graalvm.compiler.nodes.spi.VirtualizerTool;
47import org.graalvm.compiler.nodes.util.GraphUtil;
48import org.graalvm.compiler.nodes.virtual.VirtualObjectNode;
49
50import jdk.vm.ci.meta.ConstantReflectionProvider;
51import jdk.vm.ci.meta.JavaConstant;
52import jdk.vm.ci.meta.JavaKind;
53import jdk.vm.ci.meta.Value;
54
55// JaCoCo Exclude
56
57/**
58 * Compares two arrays with the same length.
59 */
60@NodeInfo(cycles = CYCLES_100, size = SIZE_50)
61public final class ArrayEqualsNode extends FixedWithNextNode implements LIRLowerable, Canonicalizable, Virtualizable, MemoryAccess {
62
63    public static final NodeClass<ArrayEqualsNode> TYPE = NodeClass.create(ArrayEqualsNode.class);
64    /** {@link JavaKind} of the arrays to compare. */
65    protected final JavaKind kind;
66
67    /** One array to be tested for equality. */
68    @Input ValueNode array1;
69
70    /** The other array to be tested for equality. */
71    @Input ValueNode array2;
72
73    /** Length of both arrays. */
74    @Input ValueNode length;
75
76    @OptionalInput(Memory) MemoryNode lastLocationAccess;
77
78    public ArrayEqualsNode(ValueNode array1, ValueNode array2, ValueNode length, @ConstantNodeParameter JavaKind kind) {
79        super(TYPE, StampFactory.forKind(JavaKind.Boolean));
80        this.kind = kind;
81        this.array1 = array1;
82        this.array2 = array2;
83        this.length = length;
84    }
85
86    public ValueNode getArray1() {
87        return array1;
88    }
89
90    public ValueNode getArray2() {
91        return array2;
92    }
93
94    public ValueNode getLength() {
95        return length;
96    }
97
98    private static boolean arrayEquals(ConstantReflectionProvider constantReflection, JavaConstant a, JavaConstant b, int len) {
99        for (int i = 0; i < len; i++) {
100            JavaConstant aElem = constantReflection.readArrayElement(a, i);
101            JavaConstant bElem = constantReflection.readArrayElement(b, i);
102            if (!constantReflection.constantEquals(aElem, bElem)) {
103                return false;
104            }
105        }
106        return true;
107    }
108
109    @Override
110    public Node canonical(CanonicalizerTool tool) {
111        if (tool.allUsagesAvailable() && hasNoUsages()) {
112            return null;
113        }
114        ValueNode a1 = GraphUtil.unproxify(array1);
115        ValueNode a2 = GraphUtil.unproxify(array2);
116        if (a1 == a2) {
117            return ConstantNode.forBoolean(true);
118        }
119        if (a1.isConstant() && a2.isConstant() && length.isConstant()) {
120            ConstantNode c1 = (ConstantNode) a1;
121            ConstantNode c2 = (ConstantNode) a2;
122            if (c1.getStableDimension() >= 1 && c2.getStableDimension() >= 1) {
123                boolean ret = arrayEquals(tool.getConstantReflection(), c1.asJavaConstant(), c2.asJavaConstant(), length.asJavaConstant().asInt());
124                return ConstantNode.forBoolean(ret);
125            }
126        }
127        return this;
128    }
129
130    @Override
131    public void virtualize(VirtualizerTool tool) {
132        ValueNode alias1 = tool.getAlias(array1);
133        ValueNode alias2 = tool.getAlias(array2);
134        if (alias1 == alias2) {
135            // the same virtual objects will always have the same contents
136            tool.replaceWithValue(ConstantNode.forBoolean(true, graph()));
137        } else if (alias1 instanceof VirtualObjectNode && alias2 instanceof VirtualObjectNode) {
138            VirtualObjectNode virtual1 = (VirtualObjectNode) alias1;
139            VirtualObjectNode virtual2 = (VirtualObjectNode) alias2;
140
141            if (virtual1.entryCount() == virtual2.entryCount()) {
142                int entryCount = virtual1.entryCount();
143                boolean allEqual = true;
144                for (int i = 0; i < entryCount; i++) {
145                    ValueNode entry1 = tool.getEntry(virtual1, i);
146                    ValueNode entry2 = tool.getEntry(virtual2, i);
147                    if (entry1 != entry2) {
148                        // the contents might be different
149                        allEqual = false;
150                    }
151                    if (entry1.stamp().alwaysDistinct(entry2.stamp())) {
152                        // the contents are different
153                        tool.replaceWithValue(ConstantNode.forBoolean(false, graph()));
154                        return;
155                    }
156                }
157                if (allEqual) {
158                    tool.replaceWithValue(ConstantNode.forBoolean(true, graph()));
159                }
160            }
161        }
162    }
163
164    @NodeIntrinsic
165    public static native boolean equals(Object array1, Object array2, int length, @ConstantNodeParameter JavaKind kind);
166
167    public static boolean equals(boolean[] array1, boolean[] array2, int length) {
168        return equals(array1, array2, length, JavaKind.Boolean);
169    }
170
171    public static boolean equals(byte[] array1, byte[] array2, int length) {
172        return equals(array1, array2, length, JavaKind.Byte);
173    }
174
175    public static boolean equals(char[] array1, char[] array2, int length) {
176        return equals(array1, array2, length, JavaKind.Char);
177    }
178
179    public static boolean equals(short[] array1, short[] array2, int length) {
180        return equals(array1, array2, length, JavaKind.Short);
181    }
182
183    public static boolean equals(int[] array1, int[] array2, int length) {
184        return equals(array1, array2, length, JavaKind.Int);
185    }
186
187    public static boolean equals(long[] array1, long[] array2, int length) {
188        return equals(array1, array2, length, JavaKind.Long);
189    }
190
191    public static boolean equals(float[] array1, float[] array2, int length) {
192        return equals(array1, array2, length, JavaKind.Float);
193    }
194
195    public static boolean equals(double[] array1, double[] array2, int length) {
196        return equals(array1, array2, length, JavaKind.Double);
197    }
198
199    @Override
200    public void generate(NodeLIRBuilderTool gen) {
201        Value result = gen.getLIRGeneratorTool().emitArrayEquals(kind, gen.operand(array1), gen.operand(array2), gen.operand(length));
202        gen.setResult(this, result);
203    }
204
205    @Override
206    public LocationIdentity getLocationIdentity() {
207        return NamedLocationIdentity.getArrayLocation(kind);
208    }
209
210    @Override
211    public MemoryNode getLastLocationAccess() {
212        return lastLocationAccess;
213    }
214
215    @Override
216    public void setLastLocationAccess(MemoryNode lla) {
217        updateUsages(ValueNodeUtil.asNode(lastLocationAccess), ValueNodeUtil.asNode(lla));
218        lastLocationAccess = lla;
219    }
220}
221