1 /*
2 * Copyright (c) 2009, 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 */
23 package org.graalvm.compiler.nodes.java;
24
25 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_8;
26 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_8;
27
28 import org.graalvm.compiler.core.common.type.Stamp;
29 import org.graalvm.compiler.core.common.type.StampFactory;
30 import org.graalvm.compiler.core.common.type.TypeReference;
31 import org.graalvm.compiler.graph.Node;
32 import org.graalvm.compiler.graph.NodeClass;
33 import org.graalvm.compiler.graph.spi.Canonicalizable;
34 import org.graalvm.compiler.graph.spi.CanonicalizerTool;
35 import org.graalvm.compiler.nodeinfo.NodeInfo;
36 import org.graalvm.compiler.nodes.ConstantNode;
37 import org.graalvm.compiler.nodes.ValueNode;
38 import org.graalvm.compiler.nodes.spi.Virtualizable;
39 import org.graalvm.compiler.nodes.spi.VirtualizerTool;
40 import org.graalvm.compiler.nodes.type.StampTool;
41 import org.graalvm.compiler.nodes.virtual.VirtualArrayNode;
42 import org.graalvm.compiler.nodes.virtual.VirtualObjectNode;
43
44 import jdk.vm.ci.meta.Assumptions;
45 import jdk.vm.ci.meta.ConstantReflectionProvider;
46 import jdk.vm.ci.meta.JavaConstant;
47 import jdk.vm.ci.meta.JavaKind;
48 import jdk.vm.ci.meta.MetaAccessProvider;
49 import jdk.vm.ci.meta.ResolvedJavaType;
50
51 /**
52 * The {@code LoadIndexedNode} represents a read from an element of an array.
53 */
54 @NodeInfo(cycles = CYCLES_8, size = SIZE_8)
55 public class LoadIndexedNode extends AccessIndexedNode implements Virtualizable, Canonicalizable {
56
57 public static final NodeClass<LoadIndexedNode> TYPE = NodeClass.create(LoadIndexedNode.class);
58
59 /**
60 * Creates a new LoadIndexedNode.
61 *
62 * @param array the instruction producing the array
63 * @param index the instruction producing the index
64 * @param elementKind the element type
65 */
66 public LoadIndexedNode(Assumptions assumptions, ValueNode array, ValueNode index, JavaKind elementKind) {
67 this(TYPE, createStamp(assumptions, array, elementKind), array, index, elementKind);
68 }
69
70 public static ValueNode create(Assumptions assumptions, ValueNode array, ValueNode index, JavaKind elementKind, MetaAccessProvider metaAccess, ConstantReflectionProvider constantReflection) {
71 ValueNode constant = tryConstantFold(array, index, metaAccess, constantReflection);
72 if (constant != null) {
73 return constant;
74 }
75 return new LoadIndexedNode(assumptions, array, index, elementKind);
76 }
77
78 protected LoadIndexedNode(NodeClass<? extends LoadIndexedNode> c, Stamp stamp, ValueNode array, ValueNode index, JavaKind elementKind) {
79 super(c, stamp, array, index, elementKind);
80 }
81
82 private static Stamp createStamp(Assumptions assumptions, ValueNode array, JavaKind kind) {
83 ResolvedJavaType type = StampTool.typeOrNull(array);
84 if (kind == JavaKind.Object && type != null && type.isArray()) {
85 return StampFactory.object(TypeReference.createTrusted(assumptions, type.getComponentType()));
86 } else {
87 return StampFactory.forKind(kind);
88 }
89 }
90
91 @Override
92 public boolean inferStamp() {
93 return updateStamp(stamp.improveWith(createStamp(graph().getAssumptions(), array(), elementKind())));
94 }
95
96 @Override
97 public void virtualize(VirtualizerTool tool) {
98 ValueNode alias = tool.getAlias(array());
99 if (alias instanceof VirtualObjectNode) {
100 VirtualArrayNode virtual = (VirtualArrayNode) alias;
101 ValueNode indexValue = tool.getAlias(index());
102 int idx = indexValue.isConstant() ? indexValue.asJavaConstant().asInt() : -1;
103 if (idx >= 0 && idx < virtual.entryCount()) {
104 ValueNode entry = tool.getEntry(virtual, idx);
105 if (stamp.isCompatible(entry.stamp())) {
106 tool.replaceWith(entry);
107 } else {
108 assert stamp().getStackKind() == JavaKind.Int && (entry.stamp().getStackKind() == JavaKind.Long || entry.getStackKind() == JavaKind.Double ||
109 entry.getStackKind() == JavaKind.Illegal) : "Can only allow different stack kind two slot marker writes on one stot fields.";
110 }
111 }
112 }
113 }
114
115 @Override
116 public Node canonical(CanonicalizerTool tool) {
117 ValueNode constant = tryConstantFold(array(), index(), tool.getMetaAccess(), tool.getConstantReflection());
118 if (constant != null) {
119 return constant;
120 }
121 return this;
122 }
123
124 private static ValueNode tryConstantFold(ValueNode array, ValueNode index, MetaAccessProvider metaAccess, ConstantReflectionProvider constantReflection) {
125 if (array.isConstant() && !array.isNullConstant() && index.isConstant()) {
126 JavaConstant arrayConstant = array.asJavaConstant();
127 if (arrayConstant != null) {
128 int stableDimension = ((ConstantNode) array).getStableDimension();
129 if (stableDimension > 0) {
130 JavaConstant constant = constantReflection.readArrayElement(arrayConstant, index.asJavaConstant().asInt());
131 boolean isDefaultStable = ((ConstantNode) array).isDefaultStable();
132 if (constant != null && (isDefaultStable || !constant.isDefaultForKind())) {
133 return ConstantNode.forConstant(constant, stableDimension - 1, isDefaultStable, metaAccess);
134 }
135 }
136 }
137 }
138 return null;
139 }
140 }