1 /*
2 * Copyright (c) 2013, 2015, 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.extended;
24
25 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_3;
26 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_1;
27
28 import org.graalvm.compiler.core.common.type.Stamp;
29 import org.graalvm.compiler.core.common.type.TypeReference;
30 import org.graalvm.compiler.debug.GraalError;
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.FixedWithNextNode;
38 import org.graalvm.compiler.nodes.ValueNode;
39 import org.graalvm.compiler.nodes.spi.Lowerable;
40 import org.graalvm.compiler.nodes.spi.LoweringTool;
41 import org.graalvm.compiler.nodes.type.StampTool;
42
43 import jdk.vm.ci.meta.Assumptions;
44 import jdk.vm.ci.meta.Assumptions.AssumptionResult;
45 import jdk.vm.ci.meta.JavaConstant;
46 import jdk.vm.ci.meta.ResolvedJavaMethod;
47 import jdk.vm.ci.meta.ResolvedJavaType;
48
49 /**
50 * Loads a method from the virtual method table of a given hub.
51 */
52 @NodeInfo(cycles = CYCLES_3, size = SIZE_1)
53 public final class LoadMethodNode extends FixedWithNextNode implements Lowerable, Canonicalizable {
54
55 public static final NodeClass<LoadMethodNode> TYPE = NodeClass.create(LoadMethodNode.class);
56 @Input ValueNode hub;
57 protected final ResolvedJavaMethod method;
58 protected final ResolvedJavaType receiverType;
59
60 /**
61 * The caller or context type used to perform access checks when resolving {@link #method}.
62 */
63 protected final ResolvedJavaType callerType;
64
65 public ValueNode getHub() {
66 return hub;
67 }
68
69 public LoadMethodNode(@InjectedNodeParameter Stamp stamp, ResolvedJavaMethod method, ResolvedJavaType receiverType, ResolvedJavaType callerType, ValueNode hub) {
70 super(TYPE, stamp);
71 this.receiverType = receiverType;
72 this.callerType = callerType;
73 this.hub = hub;
74 this.method = method;
75 assert method.isConcrete() : "Cannot load abstract method from a hub";
76 assert method.hasReceiver() : "Cannot load a static method from a hub";
77 if (!method.isInVirtualMethodTable(receiverType)) {
78 throw new GraalError("%s does not have a vtable entry in type %s", method, receiverType);
79 }
80 }
81
82 @Override
83 public void lower(LoweringTool tool) {
84 tool.getLowerer().lower(this, tool);
85 }
86
87 @Override
88 public Node canonical(CanonicalizerTool tool) {
89 if (hub instanceof LoadHubNode) {
90 ValueNode object = ((LoadHubNode) hub).getValue();
91 TypeReference type = StampTool.typeReferenceOrNull(object);
92 if (type != null) {
93 if (type.isExact()) {
94 return resolveExactMethod(tool, type.getType());
95 }
96 Assumptions assumptions = graph().getAssumptions();
97 AssumptionResult<ResolvedJavaMethod> resolvedMethod = type.getType().findUniqueConcreteMethod(method);
98 if (resolvedMethod != null && resolvedMethod.canRecordTo(assumptions) && !type.getType().isInterface() && method.getDeclaringClass().isAssignableFrom(type.getType())) {
99 resolvedMethod.recordTo(assumptions);
100 return ConstantNode.forConstant(stamp(), resolvedMethod.getResult().getEncoding(), tool.getMetaAccess());
101 }
102 }
103 }
104 if (hub.isConstant()) {
105 return resolveExactMethod(tool, tool.getConstantReflection().asJavaType(hub.asConstant()));
106 }
107
108 return this;
109 }
110
111 /**
112 * Find the method which would be loaded.
113 *
114 * @param tool
115 * @param type the exact type of object being loaded from
116 * @return the method which would be invoked for {@code type} or null if it doesn't implement
117 * the method
118 */
119 private Node resolveExactMethod(CanonicalizerTool tool, ResolvedJavaType type) {
120 ResolvedJavaMethod newMethod = type.resolveConcreteMethod(method, callerType);
121 if (newMethod == null) {
122 /*
123 * This really represent a misuse of LoadMethod since we're loading from a class which
124 * isn't known to implement the original method but for now at least fold it away.
125 */
126 return ConstantNode.forConstant(stamp(), JavaConstant.NULL_POINTER, null);
127 } else {
128 return ConstantNode.forConstant(stamp(), newMethod.getEncoding(), tool.getMetaAccess());
129 }
130 }
131
132 public ResolvedJavaMethod getMethod() {
133 return method;
134 }
135
136 public ResolvedJavaType getReceiverType() {
137 return receiverType;
138 }
139
140 public ResolvedJavaType getCallerType() {
141 return callerType;
142 }
143 }