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