1 /*
2  * Copyright (C) 2014 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_LIBARTBASE_BASE_ARENA_OBJECT_H_
18 #define ART_LIBARTBASE_BASE_ARENA_OBJECT_H_
19 
20 #include <android-base/logging.h>
21 
22 #include "arena_allocator.h"
23 #include "macros.h"
24 #include "scoped_arena_allocator.h"
25 
26 namespace art {
27 
28 // Parent for arena allocated objects giving appropriate new and delete operators.
29 template<enum ArenaAllocKind kAllocKind>
30 class ArenaObject {
31  public:
32   // Allocate a new ArenaObject of 'size' bytes in the Arena.
33   void* operator new(size_t size, ArenaAllocator* allocator) {
34     return allocator->Alloc(size, kAllocKind);
35   }
36 
37   static void* operator new(size_t size, ScopedArenaAllocator* allocator) {
38     return allocator->Alloc(size, kAllocKind);
39   }
40 
41   void operator delete(void*, size_t) {
42     LOG(FATAL) << "UNREACHABLE";
43     UNREACHABLE();
44   }
45 
46   // NOTE: Providing placement new (and matching delete) for constructing container elements.
47   ALWAYS_INLINE void* operator new(size_t, void* ptr) noexcept { return ptr; }
48   ALWAYS_INLINE void operator delete(void*, void*) noexcept { }
49 };
50 
51 
52 // Parent for arena allocated objects that get deleted, gives appropriate new and delete operators.
53 template<enum ArenaAllocKind kAllocKind>
54 class DeletableArenaObject {
55  public:
56   // Allocate a new ArenaObject of 'size' bytes in the Arena.
57   void* operator new(size_t size, ArenaAllocator* allocator) {
58     return allocator->Alloc(size, kAllocKind);
59   }
60 
61   static void* operator new(size_t size, ScopedArenaAllocator* allocator) {
62     return allocator->Alloc(size, kAllocKind);
63   }
64 
65   void operator delete(void*, size_t) {
66     // Nop.
67   }
68 };
69 
70 }  // namespace art
71 
72 #endif  // ART_LIBARTBASE_BASE_ARENA_OBJECT_H_
73