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 { 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 }