1 /*
2 * Copyright (c) 2011, 2019, 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.extended;
26
27 import static org.graalvm.compiler.core.common.GraalOptions.GeneratePIC;
28 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_2;
29 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_1;
30
31 import org.graalvm.compiler.core.common.type.AbstractPointerStamp;
32 import org.graalvm.compiler.core.common.type.ObjectStamp;
33 import org.graalvm.compiler.core.common.type.Stamp;
34 import org.graalvm.compiler.core.common.type.TypeReference;
35 import org.graalvm.compiler.graph.NodeClass;
36 import org.graalvm.compiler.graph.spi.Canonicalizable;
37 import org.graalvm.compiler.graph.spi.CanonicalizerTool;
38 import org.graalvm.compiler.nodeinfo.NodeInfo;
39 import org.graalvm.compiler.nodes.ConstantNode;
40 import org.graalvm.compiler.nodes.NodeView;
41 import org.graalvm.compiler.nodes.ValueNode;
42 import org.graalvm.compiler.nodes.calc.FloatingNode;
43 import org.graalvm.compiler.nodes.spi.Lowerable;
44 import org.graalvm.compiler.nodes.spi.LoweringTool;
45 import org.graalvm.compiler.nodes.spi.StampProvider;
46 import org.graalvm.compiler.nodes.spi.Virtualizable;
47 import org.graalvm.compiler.nodes.spi.VirtualizerTool;
48 import org.graalvm.compiler.nodes.type.StampTool;
49
50 import jdk.vm.ci.meta.ConstantReflectionProvider;
51 import jdk.vm.ci.meta.MetaAccessProvider;
52
53 /**
54 * Loads an object's hub, or null if the object is null.
55 */
56 @NodeInfo(cycles = CYCLES_2, size = SIZE_1)
57 public final class LoadHubOrNullNode extends FloatingNode implements Lowerable, Canonicalizable, Virtualizable {
58
59 public static final NodeClass<LoadHubOrNullNode> TYPE = NodeClass.create(LoadHubOrNullNode.class);
60 @Input ValueNode value;
61
62 public ValueNode getValue() {
63 return value;
64 }
65
66 private static AbstractPointerStamp hubStamp(StampProvider stampProvider, ValueNode value) {
67 assert value.stamp(NodeView.DEFAULT) instanceof ObjectStamp;
68 return stampProvider.createHubStamp(((ObjectStamp) value.stamp(NodeView.DEFAULT))).asMaybeNull();
69 }
70
71 public static ValueNode create(ValueNode value, StampProvider stampProvider, MetaAccessProvider metaAccess, ConstantReflectionProvider constantReflection) {
72 AbstractPointerStamp stamp = hubStamp(stampProvider, value);
73 return create(value, stamp, metaAccess, constantReflection);
74 }
75
76 public static ValueNode create(ValueNode value, AbstractPointerStamp stamp, MetaAccessProvider metaAccess, ConstantReflectionProvider constantReflection) {
77 ValueNode synonym = findSynonym(value, stamp, metaAccess, constantReflection);
78 if (synonym != null) {
79 return synonym;
80 }
81 return new LoadHubOrNullNode(stamp, value);
82 }
83
84 public LoadHubOrNullNode(@InjectedNodeParameter StampProvider stampProvider, ValueNode value) {
85 this(hubStamp(stampProvider, value), value);
86 }
87
88 public LoadHubOrNullNode(Stamp stamp, ValueNode value) {
89 super(TYPE, stamp);
90 this.value = value;
91 }
92
93 @Override
94 public void lower(LoweringTool tool) {
95 tool.getLowerer().lower(this, tool);
96 }
97
98 @Override
99 public ValueNode canonical(CanonicalizerTool tool) {
100 if (!GeneratePIC.getValue(tool.getOptions())) {
101 NodeView view = NodeView.from(tool);
102 MetaAccessProvider metaAccess = tool.getMetaAccess();
103 ValueNode curValue = getValue();
104 ValueNode newNode = findSynonym(curValue, (AbstractPointerStamp) stamp(view), metaAccess, tool.getConstantReflection());
105 if (newNode != null) {
106 return newNode;
107 }
108 }
109 return this;
110 }
111
112 public static ValueNode findSynonym(ValueNode curValue, AbstractPointerStamp stamp, MetaAccessProvider metaAccess, ConstantReflectionProvider constantReflection) {
113 if (StampTool.isPointerNonNull(stamp)) {
114 return LoadHubNode.create(curValue, stamp.asNonNull(), metaAccess, constantReflection);
115 }
116 return null;
117 }
118
119 @Override
120 public void virtualize(VirtualizerTool tool) {
121 if (!GeneratePIC.getValue(tool.getOptions())) {
122 ValueNode alias = tool.getAlias(getValue());
123 TypeReference type = StampTool.typeReferenceOrNull(alias);
124 if (type != null && type.isExact()) {
125 tool.replaceWithValue(ConstantNode.forConstant(stamp(NodeView.DEFAULT), tool.getConstantReflection().asObjectHub(type.getType()), tool.getMetaAccess(), graph()));
126 }
127 }
128 }
129 }