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