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 jdk.vm.ci.services.Services.IS_IN_NATIVE_IMAGE;
28 import static org.graalvm.compiler.nodes.graphbuilderconf.InvocationPlugins.resolveType;
29
30 import java.lang.reflect.Method;
31 import java.lang.reflect.Modifier;
32 import java.lang.reflect.Type;
33 import java.util.Arrays;
34 import java.util.stream.Collectors;
35
36 import org.graalvm.compiler.bytecode.BytecodeProvider;
37 import org.graalvm.compiler.debug.GraalError;
38 import org.graalvm.compiler.nodes.ValueNode;
39
40 import jdk.vm.ci.meta.MetaAccessProvider;
41 import jdk.vm.ci.meta.ResolvedJavaMethod;
42
43 /**
44 * An {@link InvocationPlugin} for a method where the implementation of the method is provided by a
45 * {@linkplain #getSubstitute(MetaAccessProvider) substitute} method. A substitute method must be
46 * static even if the substituted method is not.
47 *
48 * While performing intrinsification with method substitutions is simpler than writing an
49 * {@link InvocationPlugin} that does manual graph weaving, it has a higher compile time cost than
50 * the latter; parsing bytecodes to create nodes is slower than simply creating nodes. As such, the
51 * recommended practice is to use {@link MethodSubstitutionPlugin} only for complex
52 * intrinsifications which is typically those using non-straight-line control flow.
53 */
54 public final class MethodSubstitutionPlugin implements InvocationPlugin {
55
56 private ResolvedJavaMethod cachedSubstitute;
57
58 /**
59 * The class in which the substitute method is declared.
60 */
61 private final Class<?> declaringClass;
62
63 /**
64 * The name of the original and substitute method.
65 */
66 private final String name;
67
68 /**
69 * The parameter types of the substitute method.
70 */
71 private final Type[] parameters;
72
73 private final boolean originalIsStatic;
74
75 private final BytecodeProvider bytecodeProvider;
76
77 /**
78 * Creates a method substitution plugin.
79 *
80 * @param bytecodeProvider used to get the bytecodes to parse for the substitute method
81 * @param declaringClass the class in which the substitute method is declared
82 * @param name the name of the substitute method
83 * @param parameters the parameter types of the substitute method. If the original method is not
84 * static, then {@code parameters[0]} must be the {@link Class} value denoting
85 * {@link InvocationPlugin.Receiver}
86 */
87 public MethodSubstitutionPlugin(BytecodeProvider bytecodeProvider, Class<?> declaringClass, String name, Type... parameters) {
88 this.bytecodeProvider = bytecodeProvider;
89 this.declaringClass = declaringClass;
90 this.name = name;
91 this.parameters = parameters;
92 this.originalIsStatic = parameters.length == 0 || parameters[0] != InvocationPlugin.Receiver.class;
93 }
94
95 @Override
96 public boolean inlineOnly() {
97 // Conservatively assume MacroNodes may be used in a substitution
98 return true;
99 }
100
101 /**
102 * Gets the substitute method, resolving it first if necessary.
103 */
104 public ResolvedJavaMethod getSubstitute(MetaAccessProvider metaAccess) {
105 if (cachedSubstitute == null) {
106 cachedSubstitute = metaAccess.lookupJavaMethod(getJavaSubstitute());
107 }
108 return cachedSubstitute;
109 }
110
111 /**
112 * Gets the object used to access the bytecodes of the substitute method.
113 */
114 public BytecodeProvider getBytecodeProvider() {
115 return bytecodeProvider;
116 }
117
118 /**
119 * Gets the reflection API version of the substitution method.
120 */
121 Method getJavaSubstitute() throws GraalError {
122 Method substituteMethod = lookupSubstitute();
123 int modifiers = substituteMethod.getModifiers();
124 if (Modifier.isAbstract(modifiers) || Modifier.isNative(modifiers)) {
125 throw new GraalError("Substitution method must not be abstract or native: " + substituteMethod);
126 }
127 if (!Modifier.isStatic(modifiers)) {
128 throw new GraalError("Substitution method must be static: " + substituteMethod);
129 }
130 return substituteMethod;
131 }
132
133 /**
134 * Determines if a given method is the substitute method of this plugin.
135 */
136 private boolean isSubstitute(Method m) {
137 if (Modifier.isStatic(m.getModifiers()) && m.getName().equals(name)) {
138 if (parameters.length == m.getParameterCount()) {
139 Class<?>[] mparams = m.getParameterTypes();
140 int start = 0;
141 if (!originalIsStatic) {
142 start = 1;
143 if (!mparams[0].isAssignableFrom(resolveType(parameters[0], false))) {
144 return false;
145 }
146 }
147 for (int i = start; i < mparams.length; i++) {
148 if (mparams[i] != resolveType(parameters[i], false)) {
149 return false;
150 }
151 }
152 return true;
153 }
154 }
155 return false;
156 }
157
158 private Method lookupSubstitute(Method excluding) {
159 for (Method m : declaringClass.getDeclaredMethods()) {
160 if (!m.equals(excluding) && isSubstitute(m)) {
161 return m;
162 }
163 }
164 return null;
165 }
166
167 /**
168 * Gets the substitute method of this plugin.
169 */
170 private Method lookupSubstitute() {
171 Method m = lookupSubstitute(null);
172 if (m != null) {
173 assert lookupSubstitute(m) == null : String.format("multiple matches found for %s:%n%s%n%s", this, m, lookupSubstitute(m));
174 return m;
175 }
176 throw new GraalError("No method found specified by %s", this);
177 }
178
179 @Override
180 public boolean execute(GraphBuilderContext b, ResolvedJavaMethod targetMethod, InvocationPlugin.Receiver receiver, ValueNode[] argsIncludingReceiver) {
181 if (IS_IN_NATIVE_IMAGE) {
182 // these are currently unimplemented
183 return false;
184 }
185 ResolvedJavaMethod subst = getSubstitute(b.getMetaAccess());
186 return b.intrinsify(bytecodeProvider, targetMethod, subst, receiver, argsIncludingReceiver);
187 }
188
189 @Override
190 public StackTraceElement getApplySourceLocation(MetaAccessProvider metaAccess) {
191 Class<?> c = getClass();
192 for (Method m : c.getDeclaredMethods()) {
193 if (m.getName().equals("execute")) {
194 return metaAccess.lookupJavaMethod(m).asStackTraceElement(0);
195 }
196 }
197 throw new GraalError("could not find method named \"execute\" in " + c.getName());
198 }
199
200 @Override
201 public String toString() {
202 return String.format("%s[%s.%s(%s)]", getClass().getSimpleName(), declaringClass.getName(), name,
203 Arrays.asList(parameters).stream().map(c -> c.getTypeName()).collect(Collectors.joining(", ")));
204 }
205 }