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/enable_if.h> 28#include <__type_traits/integral_constant.h> 29#include <__type_traits/is_nothrow_default_constructible.h> 30#include <__type_traits/is_nothrow_move_assignable.h> 31#include <__type_traits/is_nothrow_move_constructible.h> 32#include <__type_traits/is_swappable.h> 33#include <__type_traits/is_trivially_destructible.h> 34#include <__type_traits/remove_reference.h> 35#include <__utility/forward.h> 36#include <__utility/move.h> 37#include <cstddef> 38 39#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 40# pragma GCC system_header 41#endif 42 43_LIBCPP_PUSH_MACROS 44#include <__undef_macros> 45 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 55{ 56public: 57 using value_type = _Tp; 58 using allocator_type = _Allocator; 59 using __alloc_rr = __libcpp_remove_reference_t<allocator_type>; 60 using __alloc_traits = allocator_traits<__alloc_rr>; 61 using reference = value_type&; 62 using const_reference = const value_type&; 63 using size_type = typename __alloc_traits::size_type; 64 using difference_type = typename __alloc_traits::difference_type; 65 using pointer = typename __alloc_traits::pointer; 66 using const_pointer = typename __alloc_traits::const_pointer; 67 using iterator = pointer; 68 using const_iterator = const_pointer; 69 70 pointer __first_; 71 pointer __begin_; 72 pointer __end_; 73 __compressed_pair<pointer, allocator_type> __end_cap_; 74 75 using __alloc_ref = __add_lvalue_reference_t<allocator_type>; 76 using __alloc_const_ref = __add_lvalue_reference_t<allocator_type>; 77 78 __split_buffer(const __split_buffer&) = delete; 79 __split_buffer& operator=(const __split_buffer&) = delete; 80 81 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer() 82 _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value) 83 : __first_(nullptr), __begin_(nullptr), __end_(nullptr), __end_cap_(nullptr, __default_init_tag()) {} 84 85 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit __split_buffer(__alloc_rr& __a) 86 : __first_(nullptr), __begin_(nullptr), __end_(nullptr), __end_cap_(nullptr, __a) {} 87 88 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit __split_buffer(const __alloc_rr& __a) 89 : __first_(nullptr), __begin_(nullptr), __end_(nullptr), __end_cap_(nullptr, __a) {} 90 91 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI 92 __split_buffer(size_type __cap, size_type __start, __alloc_rr& __a); 93 94 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer(__split_buffer&& __c) 95 _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value); 96 97 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer(__split_buffer&& __c, const __alloc_rr& __a); 98 99 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer& operator=(__split_buffer&& __c) 100 _NOEXCEPT_((__alloc_traits::propagate_on_container_move_assignment::value && 101 is_nothrow_move_assignable<allocator_type>::value) || 102 !__alloc_traits::propagate_on_container_move_assignment::value); 103 104 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI ~__split_buffer(); 105 106 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __alloc_rr& __alloc() _NOEXCEPT { return __end_cap_.second(); } 107 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const __alloc_rr& __alloc() const _NOEXCEPT { 108 return __end_cap_.second(); 109 } 110 111 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI pointer& __end_cap() _NOEXCEPT { return __end_cap_.first(); } 112 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const pointer& __end_cap() const _NOEXCEPT { 113 return __end_cap_.first(); 114 } 115 116 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT { return __begin_; } 117 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT { return __begin_; } 118 119 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT { return __end_; } 120 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT { return __end_; } 121 122 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT { __destruct_at_end(__begin_); } 123 124 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type size() const { 125 return static_cast<size_type>(__end_ - __begin_); 126 } 127 128 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI bool empty() const { return __end_ == __begin_; } 129 130 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type capacity() const { 131 return static_cast<size_type>(__end_cap() - __first_); 132 } 133 134 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type __front_spare() const { 135 return static_cast<size_type>(__begin_ - __first_); 136 } 137 138 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type __back_spare() const { 139 return static_cast<size_type>(__end_cap() - __end_); 140 } 141 142 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI reference front() { return *__begin_; } 143 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reference front() const { return *__begin_; } 144 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI reference back() { return *(__end_ - 1); } 145 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reference back() const { return *(__end_ - 1); } 146 147 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void reserve(size_type __n); 148 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void shrink_to_fit() _NOEXCEPT; 149 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void push_front(const_reference __x); 150 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void push_back(const_reference __x); 151 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void push_front(value_type&& __x); 152 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void push_back(value_type&& __x); 153 154 template <class... _Args> 155 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void emplace_back(_Args&&... __args); 156 157 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void pop_front() { __destruct_at_begin(__begin_ + 1); } 158 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void pop_back() { __destruct_at_end(__end_ - 1); } 159 160 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __construct_at_end(size_type __n); 161 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __construct_at_end(size_type __n, const_reference __x); 162 163 template <class _InputIter, __enable_if_t<__has_exactly_input_iterator_category<_InputIter>::value, int> = 0> 164 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI 165 void __construct_at_end(_InputIter __first, _InputIter __last); 166 167 template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> = 0> 168 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI 169 void __construct_at_end(_ForwardIterator __first, _ForwardIterator __last); 170 171 template <class _Iterator, class _Sentinel> 172 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI 173 void __construct_at_end_with_sentinel(_Iterator __first, _Sentinel __last); 174 175 template <class _Iterator> 176 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI 177 void __construct_at_end_with_size(_Iterator __first, size_type __n); 178 179 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_begin(pointer __new_begin) { 180 __destruct_at_begin(__new_begin, is_trivially_destructible<value_type>()); 181 } 182 183 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_begin(pointer __new_begin, false_type); 184 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_begin(pointer __new_begin, true_type); 185 186 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_end(pointer __new_last) _NOEXCEPT { 187 __destruct_at_end(__new_last, false_type()); 188 } 189 190 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_end(pointer __new_last, false_type) _NOEXCEPT; 191 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_end(pointer __new_last, true_type) _NOEXCEPT; 192 193 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void swap(__split_buffer& __x) 194 _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable<__alloc_rr>::value); 195 196 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI bool __invariants() const; 197 198private: 199 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__split_buffer& __c, true_type) 200 _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value) { 201 __alloc() = std::move(__c.__alloc()); 202 } 203 204 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__split_buffer&, false_type) _NOEXCEPT {} 205 206 struct _ConstructTransaction { 207 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit _ConstructTransaction( 208 pointer* __p, size_type __n) _NOEXCEPT 209 : __pos_(*__p), 210 __end_(*__p + __n), 211 __dest_(__p) {} 212 213 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI ~_ConstructTransaction() { *__dest_ = __pos_; } 214 215 pointer __pos_; 216 const pointer __end_; 217 218 private: 219 pointer* __dest_; 220 }; 221}; 222 223template <class _Tp, class _Allocator> 224_LIBCPP_CONSTEXPR_SINCE_CXX20 225bool 226__split_buffer<_Tp, _Allocator>::__invariants() const 227{ 228 if (__first_ == nullptr) 229 { 230 if (__begin_ != nullptr) 231 return false; 232 if (__end_ != nullptr) 233 return false; 234 if (__end_cap() != nullptr) 235 return false; 236 } 237 else 238 { 239 if (__begin_ < __first_) 240 return false; 241 if (__end_ < __begin_) 242 return false; 243 if (__end_cap() < __end_) 244 return false; 245 } 246 return true; 247} 248 249// Default constructs __n objects starting at __end_ 250// throws if construction throws 251// Precondition: __n > 0 252// Precondition: size() + __n <= capacity() 253// Postcondition: size() == size() + __n 254template <class _Tp, class _Allocator> 255_LIBCPP_CONSTEXPR_SINCE_CXX20 256void 257__split_buffer<_Tp, _Allocator>::__construct_at_end(size_type __n) 258{ 259 _ConstructTransaction __tx(&this->__end_, __n); 260 for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_) { 261 __alloc_traits::construct(this->__alloc(), std::__to_address(__tx.__pos_)); 262 } 263} 264 265// Copy constructs __n objects starting at __end_ from __x 266// throws if construction throws 267// Precondition: __n > 0 268// Precondition: size() + __n <= capacity() 269// Postcondition: size() == old size() + __n 270// Postcondition: [i] == __x for all i in [size() - __n, __n) 271template <class _Tp, class _Allocator> 272_LIBCPP_CONSTEXPR_SINCE_CXX20 273void 274__split_buffer<_Tp, _Allocator>::__construct_at_end(size_type __n, const_reference __x) 275{ 276 _ConstructTransaction __tx(&this->__end_, __n); 277 for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_) { 278 __alloc_traits::construct(this->__alloc(), 279 std::__to_address(__tx.__pos_), __x); 280 } 281} 282 283template <class _Tp, class _Allocator> 284template <class _InputIter, __enable_if_t<__has_exactly_input_iterator_category<_InputIter>::value, int> > 285_LIBCPP_CONSTEXPR_SINCE_CXX20 286void __split_buffer<_Tp, _Allocator>::__construct_at_end(_InputIter __first, _InputIter __last) 287{ 288 __construct_at_end_with_sentinel(__first, __last); 289} 290 291template <class _Tp, class _Allocator> 292template <class _Iterator, class _Sentinel> 293_LIBCPP_CONSTEXPR_SINCE_CXX20 294void __split_buffer<_Tp, _Allocator>::__construct_at_end_with_sentinel(_Iterator __first, _Sentinel __last) { 295 __alloc_rr& __a = this->__alloc(); 296 for (; __first != __last; ++__first) 297 { 298 if (__end_ == __end_cap()) 299 { 300 size_type __old_cap = __end_cap() - __first_; 301 size_type __new_cap = std::max<size_type>(2 * __old_cap, 8); 302 __split_buffer __buf(__new_cap, 0, __a); 303 for (pointer __p = __begin_; __p != __end_; ++__p, (void) ++__buf.__end_) 304 __alloc_traits::construct(__buf.__alloc(), 305 std::__to_address(__buf.__end_), std::move(*__p)); 306 swap(__buf); 307 } 308 __alloc_traits::construct(__a, std::__to_address(this->__end_), *__first); 309 ++this->__end_; 310 } 311} 312template <class _Tp, class _Allocator> 313template <class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> > 314_LIBCPP_CONSTEXPR_SINCE_CXX20 315void __split_buffer<_Tp, _Allocator>::__construct_at_end(_ForwardIterator __first, _ForwardIterator __last) 316{ 317 __construct_at_end_with_size(__first, std::distance(__first, __last)); 318} 319 320template <class _Tp, class _Allocator> 321template <class _ForwardIterator> 322_LIBCPP_CONSTEXPR_SINCE_CXX20 323void __split_buffer<_Tp, _Allocator>::__construct_at_end_with_size(_ForwardIterator __first, size_type __n) { 324 _ConstructTransaction __tx(&this->__end_, __n); 325 for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_, (void) ++__first) { 326 __alloc_traits::construct(this->__alloc(), 327 std::__to_address(__tx.__pos_), *__first); 328 } 329} 330 331template <class _Tp, class _Allocator> 332_LIBCPP_CONSTEXPR_SINCE_CXX20 333inline 334void 335__split_buffer<_Tp, _Allocator>::__destruct_at_begin(pointer __new_begin, false_type) 336{ 337 while (__begin_ != __new_begin) 338 __alloc_traits::destroy(__alloc(), std::__to_address(__begin_++)); 339} 340 341template <class _Tp, class _Allocator> 342_LIBCPP_CONSTEXPR_SINCE_CXX20 343inline 344void 345__split_buffer<_Tp, _Allocator>::__destruct_at_begin(pointer __new_begin, true_type) 346{ 347 __begin_ = __new_begin; 348} 349 350template <class _Tp, class _Allocator> 351_LIBCPP_CONSTEXPR_SINCE_CXX20 352inline _LIBCPP_HIDE_FROM_ABI 353void 354__split_buffer<_Tp, _Allocator>::__destruct_at_end(pointer __new_last, false_type) _NOEXCEPT 355{ 356 while (__new_last != __end_) 357 __alloc_traits::destroy(__alloc(), std::__to_address(--__end_)); 358} 359 360template <class _Tp, class _Allocator> 361_LIBCPP_CONSTEXPR_SINCE_CXX20 362inline _LIBCPP_HIDE_FROM_ABI 363void 364__split_buffer<_Tp, _Allocator>::__destruct_at_end(pointer __new_last, true_type) _NOEXCEPT 365{ 366 __end_ = __new_last; 367} 368 369template <class _Tp, class _Allocator> 370_LIBCPP_CONSTEXPR_SINCE_CXX20 371__split_buffer<_Tp, _Allocator>::__split_buffer(size_type __cap, size_type __start, __alloc_rr& __a) 372 : __end_cap_(nullptr, __a) 373{ 374 if (__cap == 0) { 375 __first_ = nullptr; 376 } else { 377 auto __allocation = std::__allocate_at_least(__alloc(), __cap); 378 __first_ = __allocation.ptr; 379 __cap = __allocation.count; 380 } 381 __begin_ = __end_ = __first_ + __start; 382 __end_cap() = __first_ + __cap; 383} 384 385template <class _Tp, class _Allocator> 386_LIBCPP_CONSTEXPR_SINCE_CXX20 387__split_buffer<_Tp, _Allocator>::~__split_buffer() 388{ 389 clear(); 390 if (__first_) 391 __alloc_traits::deallocate(__alloc(), __first_, capacity()); 392} 393 394template <class _Tp, class _Allocator> 395_LIBCPP_CONSTEXPR_SINCE_CXX20 396__split_buffer<_Tp, _Allocator>::__split_buffer(__split_buffer&& __c) 397 _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value) 398 : __first_(std::move(__c.__first_)), 399 __begin_(std::move(__c.__begin_)), 400 __end_(std::move(__c.__end_)), 401 __end_cap_(std::move(__c.__end_cap_)) 402{ 403 __c.__first_ = nullptr; 404 __c.__begin_ = nullptr; 405 __c.__end_ = nullptr; 406 __c.__end_cap() = nullptr; 407} 408 409template <class _Tp, class _Allocator> 410_LIBCPP_CONSTEXPR_SINCE_CXX20 411__split_buffer<_Tp, _Allocator>::__split_buffer(__split_buffer&& __c, const __alloc_rr& __a) 412 : __end_cap_(nullptr, __a) 413{ 414 if (__a == __c.__alloc()) 415 { 416 __first_ = __c.__first_; 417 __begin_ = __c.__begin_; 418 __end_ = __c.__end_; 419 __end_cap() = __c.__end_cap(); 420 __c.__first_ = nullptr; 421 __c.__begin_ = nullptr; 422 __c.__end_ = nullptr; 423 __c.__end_cap() = nullptr; 424 } 425 else 426 { 427 auto __allocation = std::__allocate_at_least(__alloc(), __c.size()); 428 __first_ = __allocation.ptr; 429 __begin_ = __end_ = __first_; 430 __end_cap() = __first_ + __allocation.count; 431 typedef move_iterator<iterator> _Ip; 432 __construct_at_end(_Ip(__c.begin()), _Ip(__c.end())); 433 } 434} 435 436template <class _Tp, class _Allocator> 437_LIBCPP_CONSTEXPR_SINCE_CXX20 438__split_buffer<_Tp, _Allocator>& 439__split_buffer<_Tp, _Allocator>::operator=(__split_buffer&& __c) 440 _NOEXCEPT_((__alloc_traits::propagate_on_container_move_assignment::value && 441 is_nothrow_move_assignable<allocator_type>::value) || 442 !__alloc_traits::propagate_on_container_move_assignment::value) 443{ 444 clear(); 445 shrink_to_fit(); 446 __first_ = __c.__first_; 447 __begin_ = __c.__begin_; 448 __end_ = __c.__end_; 449 __end_cap() = __c.__end_cap(); 450 __move_assign_alloc(__c, 451 integral_constant<bool, 452 __alloc_traits::propagate_on_container_move_assignment::value>()); 453 __c.__first_ = __c.__begin_ = __c.__end_ = __c.__end_cap() = nullptr; 454 return *this; 455} 456 457template <class _Tp, class _Allocator> 458_LIBCPP_CONSTEXPR_SINCE_CXX20 459void 460__split_buffer<_Tp, _Allocator>::swap(__split_buffer& __x) 461 _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value|| 462 __is_nothrow_swappable<__alloc_rr>::value) 463{ 464 std::swap(__first_, __x.__first_); 465 std::swap(__begin_, __x.__begin_); 466 std::swap(__end_, __x.__end_); 467 std::swap(__end_cap(), __x.__end_cap()); 468 std::__swap_allocator(__alloc(), __x.__alloc()); 469} 470 471template <class _Tp, class _Allocator> 472_LIBCPP_CONSTEXPR_SINCE_CXX20 473void 474__split_buffer<_Tp, _Allocator>::reserve(size_type __n) 475{ 476 if (__n < capacity()) 477 { 478 __split_buffer<value_type, __alloc_rr&> __t(__n, 0, __alloc()); 479 __t.__construct_at_end(move_iterator<pointer>(__begin_), 480 move_iterator<pointer>(__end_)); 481 std::swap(__first_, __t.__first_); 482 std::swap(__begin_, __t.__begin_); 483 std::swap(__end_, __t.__end_); 484 std::swap(__end_cap(), __t.__end_cap()); 485 } 486} 487 488template <class _Tp, class _Allocator> 489_LIBCPP_CONSTEXPR_SINCE_CXX20 490void 491__split_buffer<_Tp, _Allocator>::shrink_to_fit() _NOEXCEPT 492{ 493 if (capacity() > size()) 494 { 495#ifndef _LIBCPP_HAS_NO_EXCEPTIONS 496 try 497 { 498#endif // _LIBCPP_HAS_NO_EXCEPTIONS 499 __split_buffer<value_type, __alloc_rr&> __t(size(), 0, __alloc()); 500 __t.__construct_at_end(move_iterator<pointer>(__begin_), 501 move_iterator<pointer>(__end_)); 502 __t.__end_ = __t.__begin_ + (__end_ - __begin_); 503 std::swap(__first_, __t.__first_); 504 std::swap(__begin_, __t.__begin_); 505 std::swap(__end_, __t.__end_); 506 std::swap(__end_cap(), __t.__end_cap()); 507#ifndef _LIBCPP_HAS_NO_EXCEPTIONS 508 } 509 catch (...) 510 { 511 } 512#endif // _LIBCPP_HAS_NO_EXCEPTIONS 513 } 514} 515 516template <class _Tp, class _Allocator> 517_LIBCPP_CONSTEXPR_SINCE_CXX20 518void 519__split_buffer<_Tp, _Allocator>::push_front(const_reference __x) 520{ 521 if (__begin_ == __first_) 522 { 523 if (__end_ < __end_cap()) 524 { 525 difference_type __d = __end_cap() - __end_; 526 __d = (__d + 1) / 2; 527 __begin_ = std::move_backward(__begin_, __end_, __end_ + __d); 528 __end_ += __d; 529 } 530 else 531 { 532 size_type __c = std::max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1); 533 __split_buffer<value_type, __alloc_rr&> __t(__c, (__c + 3) / 4, __alloc()); 534 __t.__construct_at_end(move_iterator<pointer>(__begin_), 535 move_iterator<pointer>(__end_)); 536 std::swap(__first_, __t.__first_); 537 std::swap(__begin_, __t.__begin_); 538 std::swap(__end_, __t.__end_); 539 std::swap(__end_cap(), __t.__end_cap()); 540 } 541 } 542 __alloc_traits::construct(__alloc(), std::__to_address(__begin_-1), __x); 543 --__begin_; 544} 545 546template <class _Tp, class _Allocator> 547_LIBCPP_CONSTEXPR_SINCE_CXX20 548void 549__split_buffer<_Tp, _Allocator>::push_front(value_type&& __x) 550{ 551 if (__begin_ == __first_) 552 { 553 if (__end_ < __end_cap()) 554 { 555 difference_type __d = __end_cap() - __end_; 556 __d = (__d + 1) / 2; 557 __begin_ = std::move_backward(__begin_, __end_, __end_ + __d); 558 __end_ += __d; 559 } 560 else 561 { 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 + 3) / 4, __alloc()); 564 __t.__construct_at_end(move_iterator<pointer>(__begin_), 565 move_iterator<pointer>(__end_)); 566 std::swap(__first_, __t.__first_); 567 std::swap(__begin_, __t.__begin_); 568 std::swap(__end_, __t.__end_); 569 std::swap(__end_cap(), __t.__end_cap()); 570 } 571 } 572 __alloc_traits::construct(__alloc(), std::__to_address(__begin_-1), 573 std::move(__x)); 574 --__begin_; 575} 576 577template <class _Tp, class _Allocator> 578_LIBCPP_CONSTEXPR_SINCE_CXX20 579inline _LIBCPP_HIDE_FROM_ABI 580void 581__split_buffer<_Tp, _Allocator>::push_back(const_reference __x) 582{ 583 if (__end_ == __end_cap()) 584 { 585 if (__begin_ > __first_) 586 { 587 difference_type __d = __begin_ - __first_; 588 __d = (__d + 1) / 2; 589 __end_ = std::move(__begin_, __end_, __begin_ - __d); 590 __begin_ -= __d; 591 } 592 else 593 { 594 size_type __c = std::max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1); 595 __split_buffer<value_type, __alloc_rr&> __t(__c, __c / 4, __alloc()); 596 __t.__construct_at_end(move_iterator<pointer>(__begin_), 597 move_iterator<pointer>(__end_)); 598 std::swap(__first_, __t.__first_); 599 std::swap(__begin_, __t.__begin_); 600 std::swap(__end_, __t.__end_); 601 std::swap(__end_cap(), __t.__end_cap()); 602 } 603 } 604 __alloc_traits::construct(__alloc(), std::__to_address(__end_), __x); 605 ++__end_; 606} 607 608template <class _Tp, class _Allocator> 609_LIBCPP_CONSTEXPR_SINCE_CXX20 610void 611__split_buffer<_Tp, _Allocator>::push_back(value_type&& __x) 612{ 613 if (__end_ == __end_cap()) 614 { 615 if (__begin_ > __first_) 616 { 617 difference_type __d = __begin_ - __first_; 618 __d = (__d + 1) / 2; 619 __end_ = std::move(__begin_, __end_, __begin_ - __d); 620 __begin_ -= __d; 621 } 622 else 623 { 624 size_type __c = std::max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1); 625 __split_buffer<value_type, __alloc_rr&> __t(__c, __c / 4, __alloc()); 626 __t.__construct_at_end(move_iterator<pointer>(__begin_), 627 move_iterator<pointer>(__end_)); 628 std::swap(__first_, __t.__first_); 629 std::swap(__begin_, __t.__begin_); 630 std::swap(__end_, __t.__end_); 631 std::swap(__end_cap(), __t.__end_cap()); 632 } 633 } 634 __alloc_traits::construct(__alloc(), std::__to_address(__end_), 635 std::move(__x)); 636 ++__end_; 637} 638 639template <class _Tp, class _Allocator> 640template <class... _Args> 641_LIBCPP_CONSTEXPR_SINCE_CXX20 642void 643__split_buffer<_Tp, _Allocator>::emplace_back(_Args&&... __args) 644{ 645 if (__end_ == __end_cap()) 646 { 647 if (__begin_ > __first_) 648 { 649 difference_type __d = __begin_ - __first_; 650 __d = (__d + 1) / 2; 651 __end_ = std::move(__begin_, __end_, __begin_ - __d); 652 __begin_ -= __d; 653 } 654 else 655 { 656 size_type __c = std::max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1); 657 __split_buffer<value_type, __alloc_rr&> __t(__c, __c / 4, __alloc()); 658 __t.__construct_at_end(move_iterator<pointer>(__begin_), 659 move_iterator<pointer>(__end_)); 660 std::swap(__first_, __t.__first_); 661 std::swap(__begin_, __t.__begin_); 662 std::swap(__end_, __t.__end_); 663 std::swap(__end_cap(), __t.__end_cap()); 664 } 665 } 666 __alloc_traits::construct(__alloc(), std::__to_address(__end_), 667 std::forward<_Args>(__args)...); 668 ++__end_; 669} 670 671template <class _Tp, class _Allocator> 672_LIBCPP_CONSTEXPR_SINCE_CXX20 673inline _LIBCPP_HIDE_FROM_ABI 674void 675swap(__split_buffer<_Tp, _Allocator>& __x, __split_buffer<_Tp, _Allocator>& __y) 676 _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) 677{ 678 __x.swap(__y); 679} 680 681_LIBCPP_END_NAMESPACE_STD 682 683_LIBCPP_POP_MACROS 684 685#endif // _LIBCPP___SPLIT_BUFFER 686