1*795d594fSAndroid Build Coastguard Worker /* 2*795d594fSAndroid Build Coastguard Worker * Copyright (C) 2014 The Android Open Source Project 3*795d594fSAndroid Build Coastguard Worker * 4*795d594fSAndroid Build Coastguard Worker * Licensed under the Apache License, Version 2.0 (the "License"); 5*795d594fSAndroid Build Coastguard Worker * you may not use this file except in compliance with the License. 6*795d594fSAndroid Build Coastguard Worker * You may obtain a copy of the License at 7*795d594fSAndroid Build Coastguard Worker * 8*795d594fSAndroid Build Coastguard Worker * http://www.apache.org/licenses/LICENSE-2.0 9*795d594fSAndroid Build Coastguard Worker * 10*795d594fSAndroid Build Coastguard Worker * Unless required by applicable law or agreed to in writing, software 11*795d594fSAndroid Build Coastguard Worker * distributed under the License is distributed on an "AS IS" BASIS, 12*795d594fSAndroid Build Coastguard Worker * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13*795d594fSAndroid Build Coastguard Worker * See the License for the specific language governing permissions and 14*795d594fSAndroid Build Coastguard Worker * limitations under the License. 15*795d594fSAndroid Build Coastguard Worker */ 16*795d594fSAndroid Build Coastguard Worker 17*795d594fSAndroid Build Coastguard Worker #ifndef ART_RUNTIME_REFLECTIVE_HANDLE_H_ 18*795d594fSAndroid Build Coastguard Worker #define ART_RUNTIME_REFLECTIVE_HANDLE_H_ 19*795d594fSAndroid Build Coastguard Worker 20*795d594fSAndroid Build Coastguard Worker #include "base/macros.h" 21*795d594fSAndroid Build Coastguard Worker #include "base/value_object.h" 22*795d594fSAndroid Build Coastguard Worker #include "reflective_reference.h" 23*795d594fSAndroid Build Coastguard Worker 24*795d594fSAndroid Build Coastguard Worker namespace art HIDDEN { 25*795d594fSAndroid Build Coastguard Worker 26*795d594fSAndroid Build Coastguard Worker // This is a holder similar to Handle<T> that is used to hold reflective references to ArtField and 27*795d594fSAndroid Build Coastguard Worker // ArtMethod structures. A reflective reference is one that must be updated if the underlying class 28*795d594fSAndroid Build Coastguard Worker // or instances are replaced due to structural redefinition or some other process. In general these 29*795d594fSAndroid Build Coastguard Worker // don't need to be used. It's only when it's important that a reference to a field not become 30*795d594fSAndroid Build Coastguard Worker // obsolete and it needs to be held over a suspend point that this should be used. 31*795d594fSAndroid Build Coastguard Worker template <typename T> 32*795d594fSAndroid Build Coastguard Worker class ReflectiveHandle : public ValueObject { 33*795d594fSAndroid Build Coastguard Worker public: 34*795d594fSAndroid Build Coastguard Worker static_assert(std::is_same_v<T, ArtField> || std::is_same_v<T, ArtMethod>, 35*795d594fSAndroid Build Coastguard Worker "Expected ArtField or ArtMethod"); 36*795d594fSAndroid Build Coastguard Worker ReflectiveHandle()37*795d594fSAndroid Build Coastguard Worker ReflectiveHandle() : reference_(nullptr) {} 38*795d594fSAndroid Build Coastguard Worker 39*795d594fSAndroid Build Coastguard Worker ALWAYS_INLINE ReflectiveHandle(const ReflectiveHandle<T>& handle) = default; 40*795d594fSAndroid Build Coastguard Worker ALWAYS_INLINE ReflectiveHandle<T>& operator=(const ReflectiveHandle<T>& handle) = default; 41*795d594fSAndroid Build Coastguard Worker ReflectiveHandle(ReflectiveReference<T> * reference)42*795d594fSAndroid Build Coastguard Worker ALWAYS_INLINE explicit ReflectiveHandle(ReflectiveReference<T>* reference) 43*795d594fSAndroid Build Coastguard Worker : reference_(reference) {} 44*795d594fSAndroid Build Coastguard Worker REQUIRES_SHARED(Locks::mutator_lock_)45*795d594fSAndroid Build Coastguard Worker ALWAYS_INLINE T& operator*() const REQUIRES_SHARED(Locks::mutator_lock_) { 46*795d594fSAndroid Build Coastguard Worker return *Get(); 47*795d594fSAndroid Build Coastguard Worker } 48*795d594fSAndroid Build Coastguard Worker 49*795d594fSAndroid Build Coastguard Worker ALWAYS_INLINE T* operator->() const REQUIRES_SHARED(Locks::mutator_lock_) { 50*795d594fSAndroid Build Coastguard Worker return Get(); 51*795d594fSAndroid Build Coastguard Worker } 52*795d594fSAndroid Build Coastguard Worker Get()53*795d594fSAndroid Build Coastguard Worker ALWAYS_INLINE T* Get() const REQUIRES_SHARED(Locks::mutator_lock_) { 54*795d594fSAndroid Build Coastguard Worker return reference_->Ptr(); 55*795d594fSAndroid Build Coastguard Worker } 56*795d594fSAndroid Build Coastguard Worker IsNull()57*795d594fSAndroid Build Coastguard Worker ALWAYS_INLINE bool IsNull() const { 58*795d594fSAndroid Build Coastguard Worker // It's safe to null-check it without a read barrier. 59*795d594fSAndroid Build Coastguard Worker return reference_->IsNull(); 60*795d594fSAndroid Build Coastguard Worker } 61*795d594fSAndroid Build Coastguard Worker 62*795d594fSAndroid Build Coastguard Worker ALWAYS_INLINE bool operator!=(std::nullptr_t) const REQUIRES_SHARED(Locks::mutator_lock_) { 63*795d594fSAndroid Build Coastguard Worker return !IsNull(); 64*795d594fSAndroid Build Coastguard Worker } 65*795d594fSAndroid Build Coastguard Worker 66*795d594fSAndroid Build Coastguard Worker ALWAYS_INLINE bool operator==(std::nullptr_t) const REQUIRES_SHARED(Locks::mutator_lock_) { 67*795d594fSAndroid Build Coastguard Worker return IsNull(); 68*795d594fSAndroid Build Coastguard Worker } 69*795d594fSAndroid Build Coastguard Worker 70*795d594fSAndroid Build Coastguard Worker protected: 71*795d594fSAndroid Build Coastguard Worker ReflectiveReference<T>* reference_; 72*795d594fSAndroid Build Coastguard Worker 73*795d594fSAndroid Build Coastguard Worker private: 74*795d594fSAndroid Build Coastguard Worker friend class BaseReflectiveHandleScope; 75*795d594fSAndroid Build Coastguard Worker template <size_t kNumFieldReferences, size_t kNumMethodReferences> 76*795d594fSAndroid Build Coastguard Worker friend class StackReflectiveHandleScope; 77*795d594fSAndroid Build Coastguard Worker }; 78*795d594fSAndroid Build Coastguard Worker 79*795d594fSAndroid Build Coastguard Worker // Handles that support assignment. 80*795d594fSAndroid Build Coastguard Worker template <typename T> 81*795d594fSAndroid Build Coastguard Worker class MutableReflectiveHandle : public ReflectiveHandle<T> { 82*795d594fSAndroid Build Coastguard Worker public: MutableReflectiveHandle()83*795d594fSAndroid Build Coastguard Worker MutableReflectiveHandle() {} 84*795d594fSAndroid Build Coastguard Worker 85*795d594fSAndroid Build Coastguard Worker ALWAYS_INLINE MutableReflectiveHandle(const MutableReflectiveHandle<T>& handle) = default; 86*795d594fSAndroid Build Coastguard Worker 87*795d594fSAndroid Build Coastguard Worker ALWAYS_INLINE MutableReflectiveHandle<T>& operator=(const MutableReflectiveHandle<T>& handle) 88*795d594fSAndroid Build Coastguard Worker = default; 89*795d594fSAndroid Build Coastguard Worker MutableReflectiveHandle(ReflectiveReference<T> * reference)90*795d594fSAndroid Build Coastguard Worker ALWAYS_INLINE explicit MutableReflectiveHandle(ReflectiveReference<T>* reference) 91*795d594fSAndroid Build Coastguard Worker : ReflectiveHandle<T>(reference) {} 92*795d594fSAndroid Build Coastguard Worker Assign(T * reference)93*795d594fSAndroid Build Coastguard Worker ALWAYS_INLINE T* Assign(T* reference) REQUIRES_SHARED(Locks::mutator_lock_) { 94*795d594fSAndroid Build Coastguard Worker ReflectiveReference<T>* ref = ReflectiveHandle<T>::reference_; 95*795d594fSAndroid Build Coastguard Worker T* old = ref->Ptr(); 96*795d594fSAndroid Build Coastguard Worker ref->Assign(reference); 97*795d594fSAndroid Build Coastguard Worker return old; 98*795d594fSAndroid Build Coastguard Worker } 99*795d594fSAndroid Build Coastguard Worker 100*795d594fSAndroid Build Coastguard Worker private: 101*795d594fSAndroid Build Coastguard Worker friend class BaseReflectiveHandleScope; 102*795d594fSAndroid Build Coastguard Worker template <size_t kNumFieldReferences, size_t kNumMethodReferences> 103*795d594fSAndroid Build Coastguard Worker friend class StackReflectiveHandleScope; 104*795d594fSAndroid Build Coastguard Worker }; 105*795d594fSAndroid Build Coastguard Worker 106*795d594fSAndroid Build Coastguard Worker template<typename T> 107*795d594fSAndroid Build Coastguard Worker class ReflectiveHandleWrapper : public MutableReflectiveHandle<T> { 108*795d594fSAndroid Build Coastguard Worker public: ReflectiveHandleWrapper(T ** obj,const MutableReflectiveHandle<T> & handle)109*795d594fSAndroid Build Coastguard Worker ReflectiveHandleWrapper(T** obj, const MutableReflectiveHandle<T>& handle) 110*795d594fSAndroid Build Coastguard Worker : MutableReflectiveHandle<T>(handle), obj_(obj) { 111*795d594fSAndroid Build Coastguard Worker } 112*795d594fSAndroid Build Coastguard Worker 113*795d594fSAndroid Build Coastguard Worker ReflectiveHandleWrapper(const ReflectiveHandleWrapper&) = default; 114*795d594fSAndroid Build Coastguard Worker ~ReflectiveHandleWrapper()115*795d594fSAndroid Build Coastguard Worker ~ReflectiveHandleWrapper() { 116*795d594fSAndroid Build Coastguard Worker *obj_ = MutableReflectiveHandle<T>::Get(); 117*795d594fSAndroid Build Coastguard Worker } 118*795d594fSAndroid Build Coastguard Worker 119*795d594fSAndroid Build Coastguard Worker private: 120*795d594fSAndroid Build Coastguard Worker T** const obj_; 121*795d594fSAndroid Build Coastguard Worker }; 122*795d594fSAndroid Build Coastguard Worker 123*795d594fSAndroid Build Coastguard Worker } // namespace art 124*795d594fSAndroid Build Coastguard Worker 125*795d594fSAndroid Build Coastguard Worker #endif // ART_RUNTIME_REFLECTIVE_HANDLE_H_ 126