1 /* 2 * Copyright (c) 2014, 2017, 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 28 import java.lang.invoke.MethodHandle; 29 import java.util.Objects; 30 31 import jdk.vm.ci.common.JVMCIError; 32 import jdk.vm.ci.meta.ConstantReflectionProvider; 33 import jdk.vm.ci.meta.JavaConstant; 34 import jdk.vm.ci.meta.MethodHandleAccessProvider; 35 import jdk.vm.ci.meta.ResolvedJavaField; 36 import jdk.vm.ci.meta.ResolvedJavaMethod; 37 import jdk.vm.ci.meta.ResolvedJavaType; 38 39 public class HotSpotMethodHandleAccessProvider implements MethodHandleAccessProvider { 40 41 private final ConstantReflectionProvider constantReflection; 42 43 public HotSpotMethodHandleAccessProvider(ConstantReflectionProvider constantReflection) { 44 this.constantReflection = constantReflection; 45 } 46 47 /** 48 * Lazy initialization to break class initialization cycle. Field and method lookup is only 49 * possible after the {@link HotSpotJVMCIRuntime} is fully initialized. 50 */ 51 static class LazyInitialization { 52 static final ResolvedJavaType lambdaFormType; 53 static final ResolvedJavaField methodHandleFormField; 54 static final ResolvedJavaField lambdaFormVmentryField; 55 static final ResolvedJavaField methodField; 56 static final HotSpotResolvedJavaField vmtargetField; 57 58 /** 59 * Search for an instance field with the given name in a class. 60 * 61 * @param declaringType the type declaring the field 62 * @param fieldName name of the field to be searched 63 * @param fieldType resolved Java type of the field 64 * @return resolved Java field 65 * @throws NoSuchFieldError 66 */ 67 private static ResolvedJavaField findFieldInClass(ResolvedJavaType declaringType, String fieldName, ResolvedJavaType fieldType) { 68 ResolvedJavaField[] fields = declaringType.getInstanceFields(false); 69 for (ResolvedJavaField field : fields) { 70 if (field.getName().equals(fieldName) && field.getType().equals(fieldType)) { 71 return field; 72 } 73 } 74 throw new NoSuchFieldError(fieldType.getName() + " " + declaringType + "." + fieldName); 75 } 76 77 private static ResolvedJavaType resolveType(Class<?> c) { 78 return runtime().fromClass(c); 79 } 80 81 private static ResolvedJavaType resolveType(String className) throws ClassNotFoundException { 82 return resolveType(Class.forName(className)); 83 } 84 85 static { 86 try { 87 ResolvedJavaType methodHandleType = resolveType(MethodHandle.class); 88 ResolvedJavaType memberNameType = resolveType("java.lang.invoke.MemberName"); 89 lambdaFormType = resolveType("java.lang.invoke.LambdaForm"); 90 methodHandleFormField = findFieldInClass(methodHandleType, "form", lambdaFormType); 91 lambdaFormVmentryField = findFieldInClass(lambdaFormType, "vmentry", memberNameType); 92 ResolvedJavaType methodType = resolveType("java.lang.invoke.ResolvedMethodName"); 93 methodField = findFieldInClass(memberNameType, "method", methodType); 94 vmtargetField = (HotSpotResolvedJavaField) findFieldInClass(methodType, "vmtarget", resolveType(HotSpotJVMCIRuntime.getHostWordKind().toJavaClass())); 95 96 } catch (Throwable ex) { 97 throw new JVMCIError(ex); 98 } 99 } 100 } 101 102 @Override 103 public IntrinsicMethod lookupMethodHandleIntrinsic(ResolvedJavaMethod method) { 104 int intrinsicId = ((HotSpotResolvedJavaMethodImpl) method).intrinsicId(); 105 if (intrinsicId != 0) { 106 return getMethodHandleIntrinsic(intrinsicId); 107 } 108 return null; 109 } 110 111 public static IntrinsicMethod getMethodHandleIntrinsic(int intrinsicId) { 112 HotSpotVMConfig config = runtime().getConfig(); 113 if (intrinsicId == config.vmIntrinsicInvokeBasic) { 114 return IntrinsicMethod.INVOKE_BASIC; 115 } else if (intrinsicId == config.vmIntrinsicLinkToInterface) { 116 return IntrinsicMethod.LINK_TO_INTERFACE; 117 } else if (intrinsicId == config.vmIntrinsicLinkToSpecial) { 118 return IntrinsicMethod.LINK_TO_SPECIAL; 119 } else if (intrinsicId == config.vmIntrinsicLinkToStatic) { 120 return IntrinsicMethod.LINK_TO_STATIC; 121 } else if (intrinsicId == config.vmIntrinsicLinkToVirtual) { 122 return IntrinsicMethod.LINK_TO_VIRTUAL; 123 } 124 return null; 125 } 126 127 @Override 128 public ResolvedJavaMethod resolveInvokeBasicTarget(JavaConstant methodHandle, boolean forceBytecodeGeneration) { 129 if (methodHandle.isNull()) { 130 return null; 131 } 132 133 /* Load non-public field: LambdaForm MethodHandle.form */ 134 JavaConstant lambdaForm = constantReflection.readFieldValue(LazyInitialization.methodHandleFormField, methodHandle); 135 if (lambdaForm == null || lambdaForm.isNull()) { 136 return null; 137 } 138 139 JavaConstant memberName = constantReflection.readFieldValue(LazyInitialization.lambdaFormVmentryField, lambdaForm); 140 if (memberName.isNull() && forceBytecodeGeneration) { 141 Object lf = ((HotSpotObjectConstant) lambdaForm).asObject(LazyInitialization.lambdaFormType); 142 compilerToVM().compileToBytecode(Objects.requireNonNull(lf)); 143 memberName = constantReflection.readFieldValue(LazyInitialization.lambdaFormVmentryField, lambdaForm); 144 assert memberName.isNonNull(); 145 } 146 JavaConstant method = constantReflection.readFieldValue(LazyInitialization.methodField, memberName); 147 return getTargetMethod(method); 148 } 149 150 @Override 151 public ResolvedJavaMethod resolveLinkToTarget(JavaConstant memberName) { 152 if (memberName.isNull()) { 153 return null; 154 } 155 JavaConstant method = constantReflection.readFieldValue(LazyInitialization.methodField, memberName); 156 return getTargetMethod(method); 157 } 158 159 /** 160 * Returns the {@link ResolvedJavaMethod} for the method of a java.lang.invoke.MemberName. 161 */ 162 private static ResolvedJavaMethod getTargetMethod(JavaConstant method) { 163 if (method == null) { 164 // If readFieldValue returns NULL the type was wrong 165 throw new IllegalArgumentException("unexpected type for memberName"); 166 } 167 168 Object object = ((HotSpotObjectConstantImpl) method).object(); 169 /* Read the ResolvedJavaMethod from the injected field MemberName.method.vmtarget */ 170 return compilerToVM().getResolvedJavaMethod(object, LazyInitialization.vmtargetField.getOffset()); 171 } 172 }