1 /*
2 * Copyright (c) 2011, 2017, 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 */
23
24
25 package org.graalvm.compiler.nodes.calc;
26
27 import org.graalvm.compiler.core.common.NumUtil;
28 import org.graalvm.compiler.core.common.calc.CanonicalCondition;
29 import org.graalvm.compiler.core.common.type.IntegerStamp;
30 import org.graalvm.compiler.core.common.type.StampFactory;
31 import org.graalvm.compiler.graph.Node;
32 import org.graalvm.compiler.graph.NodeClass;
33 import org.graalvm.compiler.graph.spi.CanonicalizerTool;
34 import org.graalvm.compiler.nodeinfo.NodeInfo;
35 import org.graalvm.compiler.nodes.LogicNegationNode;
36 import org.graalvm.compiler.nodes.LogicNode;
37 import org.graalvm.compiler.nodes.NodeView;
38 import org.graalvm.compiler.nodes.ValueNode;
39 import org.graalvm.compiler.options.OptionValues;
40
41 import jdk.vm.ci.code.CodeUtil;
42 import jdk.vm.ci.meta.ConstantReflectionProvider;
43 import jdk.vm.ci.meta.MetaAccessProvider;
44 import jdk.vm.ci.meta.TriState;
45
46 @NodeInfo(shortName = "|<|")
47 public final class IntegerBelowNode extends IntegerLowerThanNode {
48 public static final NodeClass<IntegerBelowNode> TYPE = NodeClass.create(IntegerBelowNode.class);
49 private static final BelowOp OP = new BelowOp();
50
51 public IntegerBelowNode(ValueNode x, ValueNode y) {
52 super(TYPE, x, y, OP);
53 assert x.stamp(NodeView.DEFAULT) instanceof IntegerStamp;
54 assert y.stamp(NodeView.DEFAULT) instanceof IntegerStamp;
55 }
56
57 public static LogicNode create(ValueNode x, ValueNode y, NodeView view) {
58 return OP.create(x, y, view);
59 }
60
61 public static LogicNode create(ConstantReflectionProvider constantReflection, MetaAccessProvider metaAccess, OptionValues options, Integer smallestCompareWidth, ValueNode x, ValueNode y,
62 NodeView view) {
63 LogicNode value = OP.canonical(constantReflection, metaAccess, options, smallestCompareWidth, OP.getCondition(), false, x, y, view);
64 if (value != null) {
65 return value;
66 }
67 return create(x, y, view);
68 }
69
70 @Override
71 public Node canonical(CanonicalizerTool tool, ValueNode forX, ValueNode forY) {
72 NodeView view = NodeView.from(tool);
73 ValueNode value = OP.canonical(tool.getConstantReflection(), tool.getMetaAccess(), tool.getOptions(), tool.smallestCompareWidth(), OP.getCondition(), false, forX, forY, view);
74 if (value != null) {
75 return value;
76 }
77 return this;
78 }
79
80 public static class BelowOp extends LowerOp {
81 @Override
82 protected CompareNode duplicateModified(ValueNode newX, ValueNode newY, boolean unorderedIsTrue, NodeView view) {
83 assert newX.stamp(NodeView.DEFAULT) instanceof IntegerStamp && newY.stamp(NodeView.DEFAULT) instanceof IntegerStamp;
84 return new IntegerBelowNode(newX, newY);
85 }
86
87 @Override
88 protected long upperBound(IntegerStamp stamp) {
89 return stamp.unsignedUpperBound();
90 }
91
92 @Override
93 protected long lowerBound(IntegerStamp stamp) {
94 return stamp.unsignedLowerBound();
95 }
96
97 @Override
98 protected int compare(long a, long b) {
99 return Long.compareUnsigned(a, b);
100 }
101
102 @Override
103 protected long min(long a, long b) {
104 return NumUtil.minUnsigned(a, b);
105 }
106
107 @Override
108 protected long max(long a, long b) {
109 return NumUtil.maxUnsigned(a, b);
110 }
111
112 @Override
113 protected long cast(long a, int bits) {
114 return CodeUtil.zeroExtend(a, bits);
115 }
116
117 @Override
118 protected long minValue(int bits) {
119 return 0;
120 }
121
122 @Override
123 protected long maxValue(int bits) {
124 return NumUtil.maxValueUnsigned(bits);
125 }
126
127 @Override
128 protected IntegerStamp forInteger(int bits, long min, long max) {
129 return StampFactory.forUnsignedInteger(bits, min, max);
130 }
131
132 @Override
133 protected CanonicalCondition getCondition() {
134 return CanonicalCondition.BT;
135 }
136
137 @Override
138 protected IntegerLowerThanNode createNode(ValueNode x, ValueNode y) {
139 return new IntegerBelowNode(x, y);
140 }
141 }
142
143 @Override
144 public TriState implies(boolean thisNegated, LogicNode other) {
145 if (other instanceof LogicNegationNode) {
146 // Unwrap negations.
147 TriState result = implies(thisNegated, ((LogicNegationNode) other).getValue());
148 if (result.isKnown()) {
149 return TriState.get(!result.toBoolean());
150 }
151 }
152 if (!thisNegated) {
153 if (other instanceof IntegerLessThanNode) {
154 IntegerLessThanNode integerLessThanNode = (IntegerLessThanNode) other;
155 IntegerStamp stampL = (IntegerStamp) this.getY().stamp(NodeView.DEFAULT);
156 // if L >= 0:
157 if (stampL.isPositive()) { // L >= 0
158 if (this.getX() == integerLessThanNode.getX()) {
159 // x |<| L implies x < L
160 if (this.getY() == integerLessThanNode.getY()) {
161 return TriState.TRUE;
162 }
163 // x |<| L implies !(x < 0)
164 if (integerLessThanNode.getY().isConstant() &&
165 IntegerStamp.OPS.getAdd().isNeutral(integerLessThanNode.getY().asConstant())) {
166 return TriState.FALSE;
167 }
168 }
169 }
170 }
171 }
172 return super.implies(thisNegated, other);
173 }
174 }