1 /*
2 * Copyright (c) 2009, 2018, 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.java;
26
27 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_8;
28 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_8;
29
30 import org.graalvm.compiler.core.common.calc.CanonicalCondition;
31 import org.graalvm.compiler.core.common.type.ObjectStamp;
32 import org.graalvm.compiler.core.common.type.Stamp;
33 import org.graalvm.compiler.core.common.type.StampFactory;
34 import org.graalvm.compiler.core.common.type.TypeReference;
35 import org.graalvm.compiler.graph.Node;
36 import org.graalvm.compiler.graph.NodeClass;
37 import org.graalvm.compiler.graph.spi.Canonicalizable;
38 import org.graalvm.compiler.graph.spi.CanonicalizerTool;
39 import org.graalvm.compiler.graph.spi.Simplifiable;
40 import org.graalvm.compiler.graph.spi.SimplifierTool;
41 import org.graalvm.compiler.nodeinfo.NodeInfo;
42 import org.graalvm.compiler.nodes.ConstantNode;
43 import org.graalvm.compiler.nodes.DeoptimizeNode;
44 import org.graalvm.compiler.nodes.FixedGuardNode;
45 import org.graalvm.compiler.nodes.FixedWithNextNode;
46 import org.graalvm.compiler.nodes.LogicNode;
47 import org.graalvm.compiler.nodes.NodeView;
48 import org.graalvm.compiler.nodes.ValueNode;
49 import org.graalvm.compiler.nodes.calc.CompareNode;
50 import org.graalvm.compiler.nodes.extended.GuardingNode;
51 import org.graalvm.compiler.nodes.spi.Virtualizable;
52 import org.graalvm.compiler.nodes.spi.VirtualizerTool;
53 import org.graalvm.compiler.nodes.type.StampTool;
54 import org.graalvm.compiler.nodes.virtual.VirtualArrayNode;
55 import org.graalvm.compiler.nodes.virtual.VirtualObjectNode;
56
57 import jdk.vm.ci.meta.Assumptions;
58 import jdk.vm.ci.meta.ConstantReflectionProvider;
59 import jdk.vm.ci.meta.DeoptimizationAction;
60 import jdk.vm.ci.meta.DeoptimizationReason;
61 import jdk.vm.ci.meta.JavaConstant;
62 import jdk.vm.ci.meta.JavaKind;
63 import jdk.vm.ci.meta.MetaAccessProvider;
64 import jdk.vm.ci.meta.ResolvedJavaType;
65
66 /**
67 * The {@code LoadIndexedNode} represents a read from an element of an array.
68 */
69 @NodeInfo(cycles = CYCLES_8, size = SIZE_8)
70 public class LoadIndexedNode extends AccessIndexedNode implements Virtualizable, Canonicalizable, Simplifiable {
71
72 public static final NodeClass<LoadIndexedNode> TYPE = NodeClass.create(LoadIndexedNode.class);
73
74 /**
75 * Creates a new LoadIndexedNode.
76 *
77 * @param array the instruction producing the array
78 * @param index the instruction producing the index
79 * @param elementKind the element type
80 */
81 public LoadIndexedNode(Assumptions assumptions, ValueNode array, ValueNode index, GuardingNode boundsCheck, JavaKind elementKind) {
82 this(TYPE, createStamp(assumptions, array, elementKind), array, index, boundsCheck, elementKind);
83 }
84
85 public static ValueNode create(Assumptions assumptions, ValueNode array, ValueNode index, GuardingNode boundsCheck, JavaKind elementKind, MetaAccessProvider metaAccess,
86 ConstantReflectionProvider constantReflection) {
87 ValueNode constant = tryConstantFold(array, index, metaAccess, constantReflection);
88 if (constant != null) {
89 return constant;
90 }
91 return new LoadIndexedNode(assumptions, array, index, boundsCheck, elementKind);
92 }
93
94 protected LoadIndexedNode(NodeClass<? extends LoadIndexedNode> c, Stamp stamp, ValueNode array, ValueNode index, GuardingNode boundsCheck, JavaKind elementKind) {
95 super(c, stamp, array, index, boundsCheck, elementKind);
96 }
97
98 private static Stamp createStamp(Assumptions assumptions, ValueNode array, JavaKind kind) {
99 ResolvedJavaType type = StampTool.typeOrNull(array);
100 if (kind == JavaKind.Object && type != null && type.isArray()) {
101 return StampFactory.object(TypeReference.createTrusted(assumptions, type.getComponentType()));
102 } else {
103 JavaKind preciseKind = determinePreciseArrayElementType(array, kind);
104 return StampFactory.forKind(preciseKind);
105 }
106 }
107
108 private static JavaKind determinePreciseArrayElementType(ValueNode array, JavaKind kind) {
109 if (kind == JavaKind.Byte) {
110 ResolvedJavaType javaType = ((ObjectStamp) array.stamp(NodeView.DEFAULT)).type();
111 if (javaType != null && javaType.isArray() && javaType.getComponentType() != null && javaType.getComponentType().getJavaKind() == JavaKind.Boolean) {
112 return JavaKind.Boolean;
113 }
114 }
115 return kind;
116 }
117
118 @Override
119 public boolean inferStamp() {
120 return updateStamp(stamp.improveWith(createStamp(graph().getAssumptions(), array(), elementKind())));
121 }
122
123 @Override
124 public void virtualize(VirtualizerTool tool) {
125 ValueNode alias = tool.getAlias(array());
126 if (alias instanceof VirtualObjectNode) {
127 VirtualArrayNode virtual = (VirtualArrayNode) alias;
128 ValueNode indexValue = tool.getAlias(index());
129 int idx = indexValue.isConstant() ? indexValue.asJavaConstant().asInt() : -1;
130 if (idx >= 0 && idx < virtual.entryCount()) {
131 ValueNode entry = tool.getEntry(virtual, idx);
132 if (stamp.isCompatible(entry.stamp(NodeView.DEFAULT))) {
133 tool.replaceWith(entry);
134 } else {
135 assert stamp(NodeView.DEFAULT).getStackKind() == JavaKind.Int && (entry.stamp(NodeView.DEFAULT).getStackKind() == JavaKind.Long || entry.getStackKind() == JavaKind.Double ||
136 entry.getStackKind() == JavaKind.Illegal) : "Can only allow different stack kind two slot marker writes on one stot fields.";
137 }
138 }
139 }
140 }
141
142 @Override
143 public Node canonical(CanonicalizerTool tool) {
144 if (array().isNullConstant()) {
145 return new DeoptimizeNode(DeoptimizationAction.InvalidateReprofile, DeoptimizationReason.NullCheckException);
146 }
147 ValueNode constant = tryConstantFold(array(), index(), tool.getMetaAccess(), tool.getConstantReflection());
148 if (constant != null) {
149 return constant;
150 }
151 return this;
152 }
153
154 @Override
155 public void simplify(SimplifierTool tool) {
156 if (tool.allUsagesAvailable() && hasNoUsages()) {
157 NodeView view = NodeView.from(tool);
158 ValueNode arrayLength = ArrayLengthNode.create(array, tool.getConstantReflection());
159 LogicNode boundsCheck = CompareNode.createCompareNode(CanonicalCondition.BT, index, arrayLength, tool.getConstantReflection(), view);
160 if (boundsCheck.isTautology()) {
161 return;
162 }
163 if (graph().getGuardsStage().allowsGuardInsertion()) {
164 if (!arrayLength.isAlive()) {
165 arrayLength = graph().addOrUniqueWithInputs(arrayLength);
166 if (arrayLength instanceof FixedWithNextNode) {
167 FixedWithNextNode fixedArrayLength = (FixedWithNextNode) arrayLength;
168 graph().addBeforeFixed(this, fixedArrayLength);
169 }
170 }
171 boundsCheck = graph().addOrUniqueWithInputs(boundsCheck);
172 FixedGuardNode fixedGuard = new FixedGuardNode(boundsCheck, DeoptimizationReason.BoundsCheckException, DeoptimizationAction.InvalidateReprofile, false, getNodeSourcePosition());
173 graph().replaceFixedWithFixed(this, graph().add(fixedGuard));
174 }
175 }
176 }
177
178 private static ValueNode tryConstantFold(ValueNode array, ValueNode index, MetaAccessProvider metaAccess, ConstantReflectionProvider constantReflection) {
179 if (array.isConstant() && !array.isNullConstant() && index.isConstant()) {
180 JavaConstant arrayConstant = array.asJavaConstant();
181 if (arrayConstant != null) {
182 int stableDimension = ((ConstantNode) array).getStableDimension();
183 if (stableDimension > 0) {
184 JavaConstant constant = constantReflection.readArrayElement(arrayConstant, index.asJavaConstant().asInt());
185 boolean isDefaultStable = ((ConstantNode) array).isDefaultStable();
186 if (constant != null && (isDefaultStable || !constant.isDefaultForKind())) {
187 return ConstantNode.forConstant(constant, stableDimension - 1, isDefaultStable, metaAccess);
188 }
189 }
190 }
191 }
192 return null;
193 }
194 }