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  1//===----------------------------------------------------------------------===//
  2//
  3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
  4// See https://llvm.org/LICENSE.txt for license information.
  5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  6//
  7//===----------------------------------------------------------------------===//
  8
  9#ifndef _LIBCPP___MEMORY_RESOURCE_UNSYNCHRONIZED_POOL_RESOURCE_H
 10#define _LIBCPP___MEMORY_RESOURCE_UNSYNCHRONIZED_POOL_RESOURCE_H
 11
 12#include <__config>
 13#include <__cstddef/size_t.h>
 14#include <__memory_resource/memory_resource.h>
 15#include <__memory_resource/pool_options.h>
 16#include <cstdint>
 17
 18#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 19#  pragma GCC system_header
 20#endif
 21
 22#if _LIBCPP_STD_VER >= 17
 23
 24_LIBCPP_BEGIN_NAMESPACE_STD
 25
 26namespace pmr {
 27
 28// [mem.res.pool.overview]
 29
 30class _LIBCPP_AVAILABILITY_PMR _LIBCPP_EXPORTED_FROM_ABI unsynchronized_pool_resource : public memory_resource {
 31  class __fixed_pool;
 32
 33  class __adhoc_pool {
 34    struct __chunk_footer;
 35    __chunk_footer* __first_;
 36
 37  public:
 38    _LIBCPP_HIDE_FROM_ABI explicit __adhoc_pool() : __first_(nullptr) {}
 39
 40    void __release_ptr(memory_resource* __upstream);
 41    void* __do_allocate(memory_resource* __upstream, size_t __bytes, size_t __align);
 42    void __do_deallocate(memory_resource* __upstream, void* __p, size_t __bytes, size_t __align);
 43  };
 44
 45  static const size_t __min_blocks_per_chunk = 16;
 46  static const size_t __min_bytes_per_chunk  = 1024;
 47  static const size_t __max_blocks_per_chunk = (size_t(1) << 20);
 48  static const size_t __max_bytes_per_chunk  = (size_t(1) << 30);
 49
 50  static const int __log2_smallest_block_size      = 3;
 51  static const size_t __smallest_block_size        = 8;
 52  static const size_t __default_largest_block_size = (size_t(1) << 20);
 53  static const size_t __max_largest_block_size     = (size_t(1) << 30);
 54
 55  size_t __pool_block_size(int __i) const;
 56  int __log2_pool_block_size(int __i) const;
 57  int __pool_index(size_t __bytes, size_t __align) const;
 58
 59public:
 60  unsynchronized_pool_resource(const pool_options& __opts, memory_resource* __upstream);
 61
 62  _LIBCPP_HIDE_FROM_ABI unsynchronized_pool_resource()
 63      : unsynchronized_pool_resource(pool_options(), get_default_resource()) {}
 64
 65  _LIBCPP_HIDE_FROM_ABI explicit unsynchronized_pool_resource(memory_resource* __upstream)
 66      : unsynchronized_pool_resource(pool_options(), __upstream) {}
 67
 68  _LIBCPP_HIDE_FROM_ABI explicit unsynchronized_pool_resource(const pool_options& __opts)
 69      : unsynchronized_pool_resource(__opts, get_default_resource()) {}
 70
 71  unsynchronized_pool_resource(const unsynchronized_pool_resource&) = delete;
 72
 73  _LIBCPP_HIDE_FROM_ABI_VIRTUAL ~unsynchronized_pool_resource() override { release(); }
 74
 75  unsynchronized_pool_resource& operator=(const unsynchronized_pool_resource&) = delete;
 76
 77  void release();
 78
 79  _LIBCPP_HIDE_FROM_ABI memory_resource* upstream_resource() const { return __res_; }
 80
 81  [[__gnu__::__pure__]] pool_options options() const;
 82
 83protected:
 84  void* do_allocate(size_t __bytes, size_t __align) override; // key function
 85
 86  void do_deallocate(void* __p, size_t __bytes, size_t __align) override;
 87
 88  _LIBCPP_HIDE_FROM_ABI_VIRTUAL bool do_is_equal(const memory_resource& __other) const _NOEXCEPT override {
 89    return &__other == this;
 90  }
 91
 92private:
 93  memory_resource* __res_;
 94  __adhoc_pool __adhoc_pool_;
 95  __fixed_pool* __fixed_pools_;
 96  int __num_fixed_pools_;
 97  uint32_t __options_max_blocks_per_chunk_;
 98};
 99
100} // namespace pmr
101
102_LIBCPP_END_NAMESPACE_STD
103
104#endif // _LIBCPP_STD_VER >= 17
105
106#endif // _LIBCPP___MEMORY_RESOURCE_UNSYNCHRONIZED_POOL_RESOURCE_H