1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP___SPLIT_BUFFER
11#define _LIBCPP___SPLIT_BUFFER
12
13#include <__algorithm/max.h>
14#include <__algorithm/move.h>
15#include <__algorithm/move_backward.h>
16#include <__config>
17#include <__iterator/distance.h>
18#include <__iterator/iterator_traits.h>
19#include <__iterator/move_iterator.h>
20#include <__memory/allocate_at_least.h>
21#include <__memory/allocator.h>
22#include <__memory/allocator_traits.h>
23#include <__memory/compressed_pair.h>
24#include <__memory/pointer_traits.h>
25#include <__memory/swap_allocator.h>
26#include <__type_traits/add_lvalue_reference.h>
27#include <__type_traits/conditional.h>
28#include <__type_traits/enable_if.h>
29#include <__type_traits/integral_constant.h>
30#include <__type_traits/is_nothrow_assignable.h>
31#include <__type_traits/is_nothrow_constructible.h>
32#include <__type_traits/is_swappable.h>
33#include <__type_traits/is_trivially_destructible.h>
34#include <__type_traits/is_trivially_relocatable.h>
35#include <__type_traits/remove_reference.h>
36#include <__utility/forward.h>
37#include <__utility/move.h>
38#include <cstddef>
39
40#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
41# pragma GCC system_header
42#endif
43
44_LIBCPP_PUSH_MACROS
45#include <__undef_macros>
46
47_LIBCPP_BEGIN_NAMESPACE_STD
48
49// __split_buffer allocates a contiguous chunk of memory and stores objects in the range [__begin_, __end_).
50// It has uninitialized memory in the ranges [__first_, __begin_) and [__end_, __end_cap_.first()). That allows
51// it to grow both in the front and back without having to move the data.
52
53template <class _Tp, class _Allocator = allocator<_Tp> >
54struct __split_buffer {
55public:
56 using value_type = _Tp;
57 using allocator_type = _Allocator;
58 using __alloc_rr = __libcpp_remove_reference_t<allocator_type>;
59 using __alloc_traits = allocator_traits<__alloc_rr>;
60 using reference = value_type&;
61 using const_reference = const value_type&;
62 using size_type = typename __alloc_traits::size_type;
63 using difference_type = typename __alloc_traits::difference_type;
64 using pointer = typename __alloc_traits::pointer;
65 using const_pointer = typename __alloc_traits::const_pointer;
66 using iterator = pointer;
67 using const_iterator = const_pointer;
68
69 // A __split_buffer contains the following members which may be trivially relocatable:
70 // - pointer: may be trivially relocatable, so it's checked
71 // - allocator_type: may be trivially relocatable, so it's checked
72 // __split_buffer doesn't have any self-references, so it's trivially relocatable if its members are.
73 using __trivially_relocatable = __conditional_t<
74 __libcpp_is_trivially_relocatable<pointer>::value && __libcpp_is_trivially_relocatable<allocator_type>::value,
75 __split_buffer,
76 void>;
77
78 pointer __first_;
79 pointer __begin_;
80 pointer __end_;
81 __compressed_pair<pointer, allocator_type> __end_cap_;
82
83 using __alloc_ref = __add_lvalue_reference_t<allocator_type>;
84 using __alloc_const_ref = __add_lvalue_reference_t<allocator_type>;
85
86 __split_buffer(const __split_buffer&) = delete;
87 __split_buffer& operator=(const __split_buffer&) = delete;
88
89 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer()
90 _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
91 : __first_(nullptr), __begin_(nullptr), __end_(nullptr), __end_cap_(nullptr, __default_init_tag()) {}
92
93 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit __split_buffer(__alloc_rr& __a)
94 : __first_(nullptr), __begin_(nullptr), __end_(nullptr), __end_cap_(nullptr, __a) {}
95
96 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit __split_buffer(const __alloc_rr& __a)
97 : __first_(nullptr), __begin_(nullptr), __end_(nullptr), __end_cap_(nullptr, __a) {}
98
99 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
100 __split_buffer(size_type __cap, size_type __start, __alloc_rr& __a);
101
102 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer(__split_buffer&& __c)
103 _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value);
104
105 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer(__split_buffer&& __c, const __alloc_rr& __a);
106
107 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer& operator=(__split_buffer&& __c)
108 _NOEXCEPT_((__alloc_traits::propagate_on_container_move_assignment::value &&
109 is_nothrow_move_assignable<allocator_type>::value) ||
110 !__alloc_traits::propagate_on_container_move_assignment::value);
111
112 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI ~__split_buffer();
113
114 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __alloc_rr& __alloc() _NOEXCEPT { return __end_cap_.second(); }
115 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const __alloc_rr& __alloc() const _NOEXCEPT {
116 return __end_cap_.second();
117 }
118
119 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI pointer& __end_cap() _NOEXCEPT { return __end_cap_.first(); }
120 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const pointer& __end_cap() const _NOEXCEPT {
121 return __end_cap_.first();
122 }
123
124 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT { return __begin_; }
125 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT { return __begin_; }
126
127 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT { return __end_; }
128 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT { return __end_; }
129
130 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT { __destruct_at_end(__begin_); }
131
132 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type size() const {
133 return static_cast<size_type>(__end_ - __begin_);
134 }
135
136 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI bool empty() const { return __end_ == __begin_; }
137
138 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type capacity() const {
139 return static_cast<size_type>(__end_cap() - __first_);
140 }
141
142 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type __front_spare() const {
143 return static_cast<size_type>(__begin_ - __first_);
144 }
145
146 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type __back_spare() const {
147 return static_cast<size_type>(__end_cap() - __end_);
148 }
149
150 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI reference front() { return *__begin_; }
151 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reference front() const { return *__begin_; }
152 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI reference back() { return *(__end_ - 1); }
153 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reference back() const { return *(__end_ - 1); }
154
155 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void reserve(size_type __n);
156 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void shrink_to_fit() _NOEXCEPT;
157 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void push_front(const_reference __x);
158 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void push_back(const_reference __x);
159 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void push_front(value_type&& __x);
160 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void push_back(value_type&& __x);
161
162 template <class... _Args>
163 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void emplace_back(_Args&&... __args);
164
165 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void pop_front() { __destruct_at_begin(__begin_ + 1); }
166 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void pop_back() { __destruct_at_end(__end_ - 1); }
167
168 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __construct_at_end(size_type __n);
169 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __construct_at_end(size_type __n, const_reference __x);
170
171 template <class _InputIter, __enable_if_t<__has_exactly_input_iterator_category<_InputIter>::value, int> = 0>
172 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __construct_at_end(_InputIter __first, _InputIter __last);
173
174 template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> = 0>
175 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
176 __construct_at_end(_ForwardIterator __first, _ForwardIterator __last);
177
178 template <class _Iterator, class _Sentinel>
179 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
180 __construct_at_end_with_sentinel(_Iterator __first, _Sentinel __last);
181
182 template <class _Iterator>
183 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
184 __construct_at_end_with_size(_Iterator __first, size_type __n);
185
186 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_begin(pointer __new_begin) {
187 __destruct_at_begin(__new_begin, is_trivially_destructible<value_type>());
188 }
189
190 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_begin(pointer __new_begin, false_type);
191 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_begin(pointer __new_begin, true_type);
192
193 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_end(pointer __new_last) _NOEXCEPT {
194 __destruct_at_end(__new_last, false_type());
195 }
196
197 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_end(pointer __new_last, false_type) _NOEXCEPT;
198 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_end(pointer __new_last, true_type) _NOEXCEPT;
199
200 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void swap(__split_buffer& __x)
201 _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<__alloc_rr>);
202
203 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI bool __invariants() const;
204
205private:
206 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__split_buffer& __c, true_type)
207 _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value) {
208 __alloc() = std::move(__c.__alloc());
209 }
210
211 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__split_buffer&, false_type) _NOEXCEPT {}
212
213 struct _ConstructTransaction {
214 _LIBCPP_CONSTEXPR_SINCE_CXX20
215 _LIBCPP_HIDE_FROM_ABI explicit _ConstructTransaction(pointer* __p, size_type __n) _NOEXCEPT
216 : __pos_(*__p),
217 __end_(*__p + __n),
218 __dest_(__p) {}
219
220 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI ~_ConstructTransaction() { *__dest_ = __pos_; }
221
222 pointer __pos_;
223 const pointer __end_;
224
225 private:
226 pointer* __dest_;
227 };
228};
229
230template <class _Tp, class _Allocator>
231_LIBCPP_CONSTEXPR_SINCE_CXX20 bool __split_buffer<_Tp, _Allocator>::__invariants() const {
232 if (__first_ == nullptr) {
233 if (__begin_ != nullptr)
234 return false;
235 if (__end_ != nullptr)
236 return false;
237 if (__end_cap() != nullptr)
238 return false;
239 } else {
240 if (__begin_ < __first_)
241 return false;
242 if (__end_ < __begin_)
243 return false;
244 if (__end_cap() < __end_)
245 return false;
246 }
247 return true;
248}
249
250// Default constructs __n objects starting at __end_
251// throws if construction throws
252// Precondition: __n > 0
253// Precondition: size() + __n <= capacity()
254// Postcondition: size() == size() + __n
255template <class _Tp, class _Allocator>
256_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator>::__construct_at_end(size_type __n) {
257 _ConstructTransaction __tx(&this->__end_, __n);
258 for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_) {
259 __alloc_traits::construct(this->__alloc(), std::__to_address(__tx.__pos_));
260 }
261}
262
263// Copy constructs __n objects starting at __end_ from __x
264// throws if construction throws
265// Precondition: __n > 0
266// Precondition: size() + __n <= capacity()
267// Postcondition: size() == old size() + __n
268// Postcondition: [i] == __x for all i in [size() - __n, __n)
269template <class _Tp, class _Allocator>
270_LIBCPP_CONSTEXPR_SINCE_CXX20 void
271__split_buffer<_Tp, _Allocator>::__construct_at_end(size_type __n, const_reference __x) {
272 _ConstructTransaction __tx(&this->__end_, __n);
273 for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_) {
274 __alloc_traits::construct(this->__alloc(), std::__to_address(__tx.__pos_), __x);
275 }
276}
277
278template <class _Tp, class _Allocator>
279template <class _InputIter, __enable_if_t<__has_exactly_input_iterator_category<_InputIter>::value, int> >
280_LIBCPP_CONSTEXPR_SINCE_CXX20 void
281__split_buffer<_Tp, _Allocator>::__construct_at_end(_InputIter __first, _InputIter __last) {
282 __construct_at_end_with_sentinel(__first, __last);
283}
284
285template <class _Tp, class _Allocator>
286template <class _Iterator, class _Sentinel>
287_LIBCPP_CONSTEXPR_SINCE_CXX20 void
288__split_buffer<_Tp, _Allocator>::__construct_at_end_with_sentinel(_Iterator __first, _Sentinel __last) {
289 __alloc_rr& __a = this->__alloc();
290 for (; __first != __last; ++__first) {
291 if (__end_ == __end_cap()) {
292 size_type __old_cap = __end_cap() - __first_;
293 size_type __new_cap = std::max<size_type>(2 * __old_cap, 8);
294 __split_buffer __buf(__new_cap, 0, __a);
295 for (pointer __p = __begin_; __p != __end_; ++__p, (void)++__buf.__end_)
296 __alloc_traits::construct(__buf.__alloc(), std::__to_address(__buf.__end_), std::move(*__p));
297 swap(__buf);
298 }
299 __alloc_traits::construct(__a, std::__to_address(this->__end_), *__first);
300 ++this->__end_;
301 }
302}
303template <class _Tp, class _Allocator>
304template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> >
305_LIBCPP_CONSTEXPR_SINCE_CXX20 void
306__split_buffer<_Tp, _Allocator>::__construct_at_end(_ForwardIterator __first, _ForwardIterator __last) {
307 __construct_at_end_with_size(__first, std::distance(__first, __last));
308}
309
310template <class _Tp, class _Allocator>
311template <class _ForwardIterator>
312_LIBCPP_CONSTEXPR_SINCE_CXX20 void
313__split_buffer<_Tp, _Allocator>::__construct_at_end_with_size(_ForwardIterator __first, size_type __n) {
314 _ConstructTransaction __tx(&this->__end_, __n);
315 for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_, (void)++__first) {
316 __alloc_traits::construct(this->__alloc(), std::__to_address(__tx.__pos_), *__first);
317 }
318}
319
320template <class _Tp, class _Allocator>
321_LIBCPP_CONSTEXPR_SINCE_CXX20 inline void
322__split_buffer<_Tp, _Allocator>::__destruct_at_begin(pointer __new_begin, false_type) {
323 while (__begin_ != __new_begin)
324 __alloc_traits::destroy(__alloc(), std::__to_address(__begin_++));
325}
326
327template <class _Tp, class _Allocator>
328_LIBCPP_CONSTEXPR_SINCE_CXX20 inline void
329__split_buffer<_Tp, _Allocator>::__destruct_at_begin(pointer __new_begin, true_type) {
330 __begin_ = __new_begin;
331}
332
333template <class _Tp, class _Allocator>
334_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI void
335__split_buffer<_Tp, _Allocator>::__destruct_at_end(pointer __new_last, false_type) _NOEXCEPT {
336 while (__new_last != __end_)
337 __alloc_traits::destroy(__alloc(), std::__to_address(--__end_));
338}
339
340template <class _Tp, class _Allocator>
341_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI void
342__split_buffer<_Tp, _Allocator>::__destruct_at_end(pointer __new_last, true_type) _NOEXCEPT {
343 __end_ = __new_last;
344}
345
346template <class _Tp, class _Allocator>
347_LIBCPP_CONSTEXPR_SINCE_CXX20
348__split_buffer<_Tp, _Allocator>::__split_buffer(size_type __cap, size_type __start, __alloc_rr& __a)
349 : __end_cap_(nullptr, __a) {
350 if (__cap == 0) {
351 __first_ = nullptr;
352 } else {
353 auto __allocation = std::__allocate_at_least(__alloc(), __cap);
354 __first_ = __allocation.ptr;
355 __cap = __allocation.count;
356 }
357 __begin_ = __end_ = __first_ + __start;
358 __end_cap() = __first_ + __cap;
359}
360
361template <class _Tp, class _Allocator>
362_LIBCPP_CONSTEXPR_SINCE_CXX20 __split_buffer<_Tp, _Allocator>::~__split_buffer() {
363 clear();
364 if (__first_)
365 __alloc_traits::deallocate(__alloc(), __first_, capacity());
366}
367
368template <class _Tp, class _Allocator>
369_LIBCPP_CONSTEXPR_SINCE_CXX20 __split_buffer<_Tp, _Allocator>::__split_buffer(__split_buffer&& __c)
370 _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
371 : __first_(std::move(__c.__first_)),
372 __begin_(std::move(__c.__begin_)),
373 __end_(std::move(__c.__end_)),
374 __end_cap_(std::move(__c.__end_cap_)) {
375 __c.__first_ = nullptr;
376 __c.__begin_ = nullptr;
377 __c.__end_ = nullptr;
378 __c.__end_cap() = nullptr;
379}
380
381template <class _Tp, class _Allocator>
382_LIBCPP_CONSTEXPR_SINCE_CXX20
383__split_buffer<_Tp, _Allocator>::__split_buffer(__split_buffer&& __c, const __alloc_rr& __a)
384 : __end_cap_(nullptr, __a) {
385 if (__a == __c.__alloc()) {
386 __first_ = __c.__first_;
387 __begin_ = __c.__begin_;
388 __end_ = __c.__end_;
389 __end_cap() = __c.__end_cap();
390 __c.__first_ = nullptr;
391 __c.__begin_ = nullptr;
392 __c.__end_ = nullptr;
393 __c.__end_cap() = nullptr;
394 } else {
395 auto __allocation = std::__allocate_at_least(__alloc(), __c.size());
396 __first_ = __allocation.ptr;
397 __begin_ = __end_ = __first_;
398 __end_cap() = __first_ + __allocation.count;
399 typedef move_iterator<iterator> _Ip;
400 __construct_at_end(_Ip(__c.begin()), _Ip(__c.end()));
401 }
402}
403
404template <class _Tp, class _Allocator>
405_LIBCPP_CONSTEXPR_SINCE_CXX20 __split_buffer<_Tp, _Allocator>&
406__split_buffer<_Tp, _Allocator>::operator=(__split_buffer&& __c)
407 _NOEXCEPT_((__alloc_traits::propagate_on_container_move_assignment::value &&
408 is_nothrow_move_assignable<allocator_type>::value) ||
409 !__alloc_traits::propagate_on_container_move_assignment::value) {
410 clear();
411 shrink_to_fit();
412 __first_ = __c.__first_;
413 __begin_ = __c.__begin_;
414 __end_ = __c.__end_;
415 __end_cap() = __c.__end_cap();
416 __move_assign_alloc(__c, integral_constant<bool, __alloc_traits::propagate_on_container_move_assignment::value>());
417 __c.__first_ = __c.__begin_ = __c.__end_ = __c.__end_cap() = nullptr;
418 return *this;
419}
420
421template <class _Tp, class _Allocator>
422_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator>::swap(__split_buffer& __x)
423 _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<__alloc_rr>) {
424 std::swap(__first_, __x.__first_);
425 std::swap(__begin_, __x.__begin_);
426 std::swap(__end_, __x.__end_);
427 std::swap(__end_cap(), __x.__end_cap());
428 std::__swap_allocator(__alloc(), __x.__alloc());
429}
430
431template <class _Tp, class _Allocator>
432_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator>::reserve(size_type __n) {
433 if (__n < capacity()) {
434 __split_buffer<value_type, __alloc_rr&> __t(__n, 0, __alloc());
435 __t.__construct_at_end(move_iterator<pointer>(__begin_), move_iterator<pointer>(__end_));
436 std::swap(__first_, __t.__first_);
437 std::swap(__begin_, __t.__begin_);
438 std::swap(__end_, __t.__end_);
439 std::swap(__end_cap(), __t.__end_cap());
440 }
441}
442
443template <class _Tp, class _Allocator>
444_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator>::shrink_to_fit() _NOEXCEPT {
445 if (capacity() > size()) {
446#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
447 try {
448#endif // _LIBCPP_HAS_NO_EXCEPTIONS
449 __split_buffer<value_type, __alloc_rr&> __t(size(), 0, __alloc());
450 __t.__construct_at_end(move_iterator<pointer>(__begin_), move_iterator<pointer>(__end_));
451 __t.__end_ = __t.__begin_ + (__end_ - __begin_);
452 std::swap(__first_, __t.__first_);
453 std::swap(__begin_, __t.__begin_);
454 std::swap(__end_, __t.__end_);
455 std::swap(__end_cap(), __t.__end_cap());
456#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
457 } catch (...) {
458 }
459#endif // _LIBCPP_HAS_NO_EXCEPTIONS
460 }
461}
462
463template <class _Tp, class _Allocator>
464_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator>::push_front(const_reference __x) {
465 if (__begin_ == __first_) {
466 if (__end_ < __end_cap()) {
467 difference_type __d = __end_cap() - __end_;
468 __d = (__d + 1) / 2;
469 __begin_ = std::move_backward(__begin_, __end_, __end_ + __d);
470 __end_ += __d;
471 } else {
472 size_type __c = std::max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1);
473 __split_buffer<value_type, __alloc_rr&> __t(__c, (__c + 3) / 4, __alloc());
474 __t.__construct_at_end(move_iterator<pointer>(__begin_), move_iterator<pointer>(__end_));
475 std::swap(__first_, __t.__first_);
476 std::swap(__begin_, __t.__begin_);
477 std::swap(__end_, __t.__end_);
478 std::swap(__end_cap(), __t.__end_cap());
479 }
480 }
481 __alloc_traits::construct(__alloc(), std::__to_address(__begin_ - 1), __x);
482 --__begin_;
483}
484
485template <class _Tp, class _Allocator>
486_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator>::push_front(value_type&& __x) {
487 if (__begin_ == __first_) {
488 if (__end_ < __end_cap()) {
489 difference_type __d = __end_cap() - __end_;
490 __d = (__d + 1) / 2;
491 __begin_ = std::move_backward(__begin_, __end_, __end_ + __d);
492 __end_ += __d;
493 } else {
494 size_type __c = std::max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1);
495 __split_buffer<value_type, __alloc_rr&> __t(__c, (__c + 3) / 4, __alloc());
496 __t.__construct_at_end(move_iterator<pointer>(__begin_), move_iterator<pointer>(__end_));
497 std::swap(__first_, __t.__first_);
498 std::swap(__begin_, __t.__begin_);
499 std::swap(__end_, __t.__end_);
500 std::swap(__end_cap(), __t.__end_cap());
501 }
502 }
503 __alloc_traits::construct(__alloc(), std::__to_address(__begin_ - 1), std::move(__x));
504 --__begin_;
505}
506
507template <class _Tp, class _Allocator>
508_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI void
509__split_buffer<_Tp, _Allocator>::push_back(const_reference __x) {
510 if (__end_ == __end_cap()) {
511 if (__begin_ > __first_) {
512 difference_type __d = __begin_ - __first_;
513 __d = (__d + 1) / 2;
514 __end_ = std::move(__begin_, __end_, __begin_ - __d);
515 __begin_ -= __d;
516 } else {
517 size_type __c = std::max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1);
518 __split_buffer<value_type, __alloc_rr&> __t(__c, __c / 4, __alloc());
519 __t.__construct_at_end(move_iterator<pointer>(__begin_), move_iterator<pointer>(__end_));
520 std::swap(__first_, __t.__first_);
521 std::swap(__begin_, __t.__begin_);
522 std::swap(__end_, __t.__end_);
523 std::swap(__end_cap(), __t.__end_cap());
524 }
525 }
526 __alloc_traits::construct(__alloc(), std::__to_address(__end_), __x);
527 ++__end_;
528}
529
530template <class _Tp, class _Allocator>
531_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator>::push_back(value_type&& __x) {
532 if (__end_ == __end_cap()) {
533 if (__begin_ > __first_) {
534 difference_type __d = __begin_ - __first_;
535 __d = (__d + 1) / 2;
536 __end_ = std::move(__begin_, __end_, __begin_ - __d);
537 __begin_ -= __d;
538 } else {
539 size_type __c = std::max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1);
540 __split_buffer<value_type, __alloc_rr&> __t(__c, __c / 4, __alloc());
541 __t.__construct_at_end(move_iterator<pointer>(__begin_), move_iterator<pointer>(__end_));
542 std::swap(__first_, __t.__first_);
543 std::swap(__begin_, __t.__begin_);
544 std::swap(__end_, __t.__end_);
545 std::swap(__end_cap(), __t.__end_cap());
546 }
547 }
548 __alloc_traits::construct(__alloc(), std::__to_address(__end_), std::move(__x));
549 ++__end_;
550}
551
552template <class _Tp, class _Allocator>
553template <class... _Args>
554_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator>::emplace_back(_Args&&... __args) {
555 if (__end_ == __end_cap()) {
556 if (__begin_ > __first_) {
557 difference_type __d = __begin_ - __first_;
558 __d = (__d + 1) / 2;
559 __end_ = std::move(__begin_, __end_, __begin_ - __d);
560 __begin_ -= __d;
561 } else {
562 size_type __c = std::max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1);
563 __split_buffer<value_type, __alloc_rr&> __t(__c, __c / 4, __alloc());
564 __t.__construct_at_end(move_iterator<pointer>(__begin_), move_iterator<pointer>(__end_));
565 std::swap(__first_, __t.__first_);
566 std::swap(__begin_, __t.__begin_);
567 std::swap(__end_, __t.__end_);
568 std::swap(__end_cap(), __t.__end_cap());
569 }
570 }
571 __alloc_traits::construct(__alloc(), std::__to_address(__end_), std::forward<_Args>(__args)...);
572 ++__end_;
573}
574
575template <class _Tp, class _Allocator>
576_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI void
577swap(__split_buffer<_Tp, _Allocator>& __x, __split_buffer<_Tp, _Allocator>& __y) _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
578 __x.swap(__y);
579}
580
581_LIBCPP_END_NAMESPACE_STD
582
583_LIBCPP_POP_MACROS
584
585#endif // _LIBCPP___SPLIT_BUFFER
586