1 /*
2 * Copyright (c) 2015, 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.graphbuilderconf;
26
27 import static org.graalvm.compiler.nodes.graphbuilderconf.InvocationPlugins.resolveType;
28
29 import java.lang.reflect.Method;
30 import java.lang.reflect.Modifier;
31 import java.lang.reflect.Type;
32 import java.util.Arrays;
33 import java.util.stream.Collectors;
34
35 import org.graalvm.compiler.bytecode.BytecodeProvider;
36 import org.graalvm.compiler.debug.GraalError;
37 import org.graalvm.compiler.nodes.ValueNode;
38
39 import jdk.vm.ci.meta.MetaAccessProvider;
40 import jdk.vm.ci.meta.ResolvedJavaMethod;
41
42 /**
43 * An {@link InvocationPlugin} for a method where the implementation of the method is provided by a
44 * {@linkplain #getSubstitute(MetaAccessProvider) substitute} method. A substitute method must be
45 * static even if the substituted method is not.
46 *
47 * While performing intrinsification with method substitutions is simpler than writing an
48 * {@link InvocationPlugin} that does manual graph weaving, it has a higher compile time cost than
49 * the latter; parsing bytecodes to create nodes is slower than simply creating nodes. As such, the
50 * recommended practice is to use {@link MethodSubstitutionPlugin} only for complex
51 * intrinsifications which is typically those using non-straight-line control flow.
52 */
53 public final class MethodSubstitutionPlugin implements InvocationPlugin {
54
55 private ResolvedJavaMethod cachedSubstitute;
56
57 /**
58 * The class in which the substitute method is declared.
59 */
60 private final Class<?> declaringClass;
61
62 /**
63 * The name of the original and substitute method.
64 */
65 private final String name;
66
67 /**
68 * The parameter types of the substitute method.
69 */
70 private final Type[] parameters;
71
72 private final boolean originalIsStatic;
73
74 private final BytecodeProvider bytecodeProvider;
75
76 /**
77 * Creates a method substitution plugin.
78 *
79 * @param bytecodeProvider used to get the bytecodes to parse for the substitute method
80 * @param declaringClass the class in which the substitute method is declared
81 * @param name the name of the substitute method
82 * @param parameters the parameter types of the substitute method. If the original method is not
83 * static, then {@code parameters[0]} must be the {@link Class} value denoting
84 * {@link InvocationPlugin.Receiver}
85 */
86 public MethodSubstitutionPlugin(BytecodeProvider bytecodeProvider, Class<?> declaringClass, String name, Type... parameters) {
87 this.bytecodeProvider = bytecodeProvider;
88 this.declaringClass = declaringClass;
89 this.name = name;
90 this.parameters = parameters;
91 this.originalIsStatic = parameters.length == 0 || parameters[0] != InvocationPlugin.Receiver.class;
92 }
93
94 @Override
95 public boolean inlineOnly() {
96 // Conservatively assume MacroNodes may be used in a substitution
97 return true;
98 }
99
100 /**
101 * Gets the substitute method, resolving it first if necessary.
102 */
103 public ResolvedJavaMethod getSubstitute(MetaAccessProvider metaAccess) {
104 if (cachedSubstitute == null) {
105 cachedSubstitute = metaAccess.lookupJavaMethod(getJavaSubstitute());
106 }
107 return cachedSubstitute;
108 }
109
110 /**
111 * Gets the object used to access the bytecodes of the substitute method.
112 */
113 public BytecodeProvider getBytecodeProvider() {
114 return bytecodeProvider;
115 }
116
117 /**
118 * Gets the reflection API version of the substitution method.
119 */
120 Method getJavaSubstitute() throws GraalError {
121 Method substituteMethod = lookupSubstitute();
122 int modifiers = substituteMethod.getModifiers();
123 if (Modifier.isAbstract(modifiers) || Modifier.isNative(modifiers)) {
124 throw new GraalError("Substitution method must not be abstract or native: " + substituteMethod);
125 }
126 if (!Modifier.isStatic(modifiers)) {
127 throw new GraalError("Substitution method must be static: " + substituteMethod);
128 }
129 return substituteMethod;
130 }
131
132 /**
133 * Determines if a given method is the substitute method of this plugin.
134 */
135 private boolean isSubstitute(Method m) {
136 if (Modifier.isStatic(m.getModifiers()) && m.getName().equals(name)) {
137 if (parameters.length == m.getParameterCount()) {
138 Class<?>[] mparams = m.getParameterTypes();
139 int start = 0;
140 if (!originalIsStatic) {
141 start = 1;
142 if (!mparams[0].isAssignableFrom(resolveType(parameters[0], false))) {
143 return false;
144 }
145 }
146 for (int i = start; i < mparams.length; i++) {
147 if (mparams[i] != resolveType(parameters[i], false)) {
148 return false;
149 }
150 }
151 return true;
152 }
153 }
154 return false;
155 }
156
157 private Method lookupSubstitute(Method excluding) {
158 for (Method m : declaringClass.getDeclaredMethods()) {
159 if (!m.equals(excluding) && isSubstitute(m)) {
160 return m;
161 }
162 }
163 return null;
164 }
165
166 /**
167 * Gets the substitute method of this plugin.
168 */
169 private Method lookupSubstitute() {
170 Method m = lookupSubstitute(null);
171 if (m != null) {
172 assert lookupSubstitute(m) == null : String.format("multiple matches found for %s:%n%s%n%s", this, m, lookupSubstitute(m));
173 return m;
174 }
175 throw new GraalError("No method found specified by %s", this);
176 }
177
178 @Override
179 public boolean execute(GraphBuilderContext b, ResolvedJavaMethod targetMethod, InvocationPlugin.Receiver receiver, ValueNode[] argsIncludingReceiver) {
180 ResolvedJavaMethod subst = getSubstitute(b.getMetaAccess());
181 return b.intrinsify(bytecodeProvider, targetMethod, subst, receiver, argsIncludingReceiver);
182 }
183
184 @Override
185 public StackTraceElement getApplySourceLocation(MetaAccessProvider metaAccess) {
186 Class<?> c = getClass();
187 for (Method m : c.getDeclaredMethods()) {
188 if (m.getName().equals("execute")) {
189 return metaAccess.lookupJavaMethod(m).asStackTraceElement(0);
190 }
191 }
192 throw new GraalError("could not find method named \"execute\" in " + c.getName());
193 }
194
195 @Override
196 public String toString() {
197 return String.format("%s[%s.%s(%s)]", getClass().getSimpleName(), declaringClass.getName(), name,
198 Arrays.asList(parameters).stream().map(c -> c.getTypeName()).collect(Collectors.joining(", ")));
199 }
200 }