1 /*
2 * Copyright (c) 2014, 2014, 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 jdk.vm.ci.hotspot;
24
25 import static jdk.vm.ci.hotspot.CompilerToVM.compilerToVM;
26 import static jdk.vm.ci.hotspot.HotSpotJVMCIRuntime.runtime;
27 import static jdk.vm.ci.hotspot.HotSpotResolvedObjectTypeImpl.fromObjectClass;
28 import jdk.vm.ci.common.JVMCIError;
29 import jdk.vm.ci.meta.ConstantReflectionProvider;
30 import jdk.vm.ci.meta.JavaConstant;
31 import jdk.vm.ci.meta.MethodHandleAccessProvider;
32 import jdk.vm.ci.meta.ResolvedJavaField;
33 import jdk.vm.ci.meta.ResolvedJavaMethod;
34 import jdk.vm.ci.meta.ResolvedJavaType;
35
36 public class HotSpotMethodHandleAccessProvider implements MethodHandleAccessProvider, HotSpotProxified {
37
38 private final ConstantReflectionProvider constantReflection;
39
40 public HotSpotMethodHandleAccessProvider(ConstantReflectionProvider constantReflection) {
41 this.constantReflection = constantReflection;
42 }
43
44 /**
45 * Lazy initialization to break class initialization cycle. Field and method lookup is only
46 * possible after the {@link HotSpotJVMCIRuntime} is fully initialized.
47 */
48 static class LazyInitialization {
49 static final ResolvedJavaField methodHandleFormField;
50 static final ResolvedJavaField lambdaFormVmentryField;
51 static final ResolvedJavaMethod lambdaFormCompileToBytecodeMethod;
52 static final HotSpotResolvedJavaField memberNameVmtargetField;
53
54 /**
55 * Search for an instance field with the given name in a class.
56 *
57 * @param className name of the class to search in
58 * @param fieldName name of the field to be searched
59 * @return resolved java field
60 * @throws ClassNotFoundException
61 */
62 private static ResolvedJavaField findFieldInClass(String className, String fieldName) throws ClassNotFoundException {
63 Class<?> clazz = Class.forName(className);
64 ResolvedJavaType type = runtime().fromClass(clazz);
65 ResolvedJavaField[] fields = type.getInstanceFields(false);
66 for (ResolvedJavaField field : fields) {
67 if (field.getName().equals(fieldName)) {
68 return field;
69 }
70 }
71 return null;
72 }
73
74 private static ResolvedJavaMethod findMethodInClass(String className, String methodName) throws ClassNotFoundException {
75 Class<?> clazz = Class.forName(className);
76 HotSpotResolvedObjectTypeImpl type = fromObjectClass(clazz);
77 ResolvedJavaMethod result = null;
78 for (ResolvedJavaMethod method : type.getDeclaredMethods()) {
79 if (method.getName().equals(methodName)) {
80 assert result == null : "more than one method found: " + className + "." + methodName;
81 result = method;
82 }
83 }
84 assert result != null : "method not found: " + className + "." + methodName;
85 return result;
86 }
87
88 static {
89 try {
90 methodHandleFormField = findFieldInClass("java.lang.invoke.MethodHandle", "form");
91 lambdaFormVmentryField = findFieldInClass("java.lang.invoke.LambdaForm", "vmentry");
92 lambdaFormCompileToBytecodeMethod = findMethodInClass("java.lang.invoke.LambdaForm", "compileToBytecode");
93 memberNameVmtargetField = (HotSpotResolvedJavaField) findFieldInClass("java.lang.invoke.MemberName", "vmtarget");
94 } catch (Throwable ex) {
95 throw new JVMCIError(ex);
96 }
97 }
98 }
99
100 @Override
101 public IntrinsicMethod lookupMethodHandleIntrinsic(ResolvedJavaMethod method) {
102 int intrinsicId = ((HotSpotResolvedJavaMethodImpl) method).intrinsicId();
103 if (intrinsicId != 0) {
104 return getMethodHandleIntrinsic(intrinsicId);
105 }
106 return null;
107 }
108
109 public static IntrinsicMethod getMethodHandleIntrinsic(int intrinsicId) {
110 HotSpotVMConfig config = runtime().getConfig();
111 if (intrinsicId == config.vmIntrinsicInvokeBasic) {
112 return IntrinsicMethod.INVOKE_BASIC;
113 } else if (intrinsicId == config.vmIntrinsicLinkToInterface) {
114 return IntrinsicMethod.LINK_TO_INTERFACE;
115 } else if (intrinsicId == config.vmIntrinsicLinkToSpecial) {
116 return IntrinsicMethod.LINK_TO_SPECIAL;
117 } else if (intrinsicId == config.vmIntrinsicLinkToStatic) {
118 return IntrinsicMethod.LINK_TO_STATIC;
119 } else if (intrinsicId == config.vmIntrinsicLinkToVirtual) {
120 return IntrinsicMethod.LINK_TO_VIRTUAL;
121 }
122 return null;
123 }
124
125 @Override
126 public ResolvedJavaMethod resolveInvokeBasicTarget(JavaConstant methodHandle, boolean forceBytecodeGeneration) {
127 if (methodHandle.isNull()) {
128 return null;
129 }
130
131 /* Load non-public field: LambdaForm MethodHandle.form */
132 JavaConstant lambdaForm = constantReflection.readFieldValue(LazyInitialization.methodHandleFormField, methodHandle);
133 if (lambdaForm == null || lambdaForm.isNull()) {
134 return null;
135 }
136
137 JavaConstant memberName;
138 if (forceBytecodeGeneration) {
139 /* Invoke non-public method: MemberName LambdaForm.compileToBytecode() */
140 memberName = LazyInitialization.lambdaFormCompileToBytecodeMethod.invoke(lambdaForm, new JavaConstant[0]);
141 } else {
142 /* Load non-public field: MemberName LambdaForm.vmentry */
143 memberName = constantReflection.readFieldValue(LazyInitialization.lambdaFormVmentryField, lambdaForm);
144 }
145 return getTargetMethod(memberName);
146 }
147
148 @Override
149 public ResolvedJavaMethod resolveLinkToTarget(JavaConstant memberName) {
150 return getTargetMethod(memberName);
151 }
152
153 /**
154 * Returns the {@link ResolvedJavaMethod} for the vmtarget of a java.lang.invoke.MemberName.
155 */
156 private static ResolvedJavaMethod getTargetMethod(JavaConstant memberName) {
157 if (memberName.isNull()) {
158 return null;
159 }
160
161 Object object = ((HotSpotObjectConstantImpl) memberName).object();
162 /* Read the ResolvedJavaMethod from the injected field MemberName.vmtarget */
163 return compilerToVM().getResolvedJavaMethod(object, LazyInitialization.memberNameVmtargetField.offset());
164 }
165 }