1/*
2 * Copyright (c) 2024 Huawei Device Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 *     http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16#ifndef ECMASCRIPT_THREAD_LOCAL_ALLOCATION_BUFFER_H
17#define ECMASCRIPT_THREAD_LOCAL_ALLOCATION_BUFFER_H
18
19#include "ecmascript/mem/allocator-inl.h"
20
21namespace panda::ecmascript {
22class ThreadLocalAllocationBuffer {
23public:
24    // perhaps need calculate tlab size dynamically.
25    static constexpr size_t TLAB_SIZE = 8_KB;
26    static constexpr size_t INIT_WASTE_LIMIT = 64;
27    static constexpr size_t INCREASE_WASTE_SIZE = 64;
28    ThreadLocalAllocationBuffer(Heap *heap) : heap_(heap) {}
29    ~ThreadLocalAllocationBuffer() = default;
30    NO_COPY_SEMANTIC(ThreadLocalAllocationBuffer);
31    NO_MOVE_SEMANTIC(ThreadLocalAllocationBuffer);
32
33    void Reset(uintptr_t begin = 0, uintptr_t end = 0, uintptr_t top = 0);
34
35    void FillBumpPointer();
36
37    uintptr_t Allocate(size_t size)
38    {
39        return bpAllocator_.Allocate(size);
40    }
41
42    size_t Available() const
43    {
44        return bpAllocator_.Available();
45    }
46
47    uintptr_t GetTop() const
48    {
49        return bpAllocator_.GetTop();
50    }
51
52    const uintptr_t *GetTopAddress()
53    {
54        return bpAllocator_.GetTopAddress();
55    }
56
57    const uintptr_t *GetEndAddress()
58    {
59        return bpAllocator_.GetEndAddress();
60    }
61
62    size_t GetTlabWasteLimit() const
63    {
64        return tlabWasteLimit_;
65    }
66
67    size_t ComputeSize() const
68    {
69        return TLAB_SIZE;
70    }
71
72    inline bool NeedNewTlab(size_t size)
73    {
74        if (size > TLAB_SIZE) {
75            return false;
76        }
77        if (bpAllocator_.Available() >= tlabWasteLimit_) {
78            tlabWasteLimit_ += INCREASE_WASTE_SIZE;
79            return false;
80        }
81        if (disabled_) {
82            return false;
83        }
84        return true;
85    }
86
87    void DisableNewTlab()
88    {
89        disabled_ = true;
90    }
91
92private:
93    bool disabled_ {false};
94    Heap *heap_ {nullptr};
95    BumpPointerAllocator bpAllocator_;
96    size_t tlabWasteLimit_ {INIT_WASTE_LIMIT};
97};
98}  //  namespace panda::ecmascript
99
100#endif  // ECMASCRIPT_THREAD_LOCAL_ALLOCATION_BUFFER_H
101