1 /* 2 * Copyright (C) 2018 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef ART_RUNTIME_WRITE_BARRIER_H_ 18 #define ART_RUNTIME_WRITE_BARRIER_H_ 19 20 #include "base/macros.h" 21 22 namespace art { 23 24 namespace gc { 25 namespace accounting { 26 class CardTable; 27 } // namespace accounting 28 } // namespace gc 29 30 class WriteBarrier { 31 public: 32 enum NullCheck { 33 kWithoutNullCheck, 34 kWithNullCheck, 35 }; 36 37 // Must be called if a reference field of an Object in the heap changes, and before any GC 38 // safe-point. The call is not needed if null is stored in the field. 39 template <NullCheck kNullCheck = kWithNullCheck> 40 ALWAYS_INLINE static void ForFieldWrite(ObjPtr<mirror::Object> dst, 41 MemberOffset offset ATTRIBUTE_UNUSED, 42 ObjPtr<mirror::Object> new_value ATTRIBUTE_UNUSED) 43 REQUIRES_SHARED(Locks::mutator_lock_); 44 45 // Must be called if a reference field of an ObjectArray in the heap changes, and before any GC 46 // safe-point. The call is not needed if null is stored in the field. 47 ALWAYS_INLINE static void ForArrayWrite(ObjPtr<mirror::Object> dst, 48 int start_offset ATTRIBUTE_UNUSED, 49 size_t length ATTRIBUTE_UNUSED) 50 REQUIRES_SHARED(Locks::mutator_lock_); 51 52 // Write barrier for every reference field in an object. 53 ALWAYS_INLINE static void ForEveryFieldWrite(ObjPtr<mirror::Object> obj) 54 REQUIRES_SHARED(Locks::mutator_lock_); 55 56 private: 57 ALWAYS_INLINE static gc::accounting::CardTable* GetCardTable(); 58 }; 59 60 } // namespace art 61 62 #endif // ART_RUNTIME_WRITE_BARRIER_H_ 63