xref: /freebsd/contrib/llvm-project/libcxx/include/deque (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
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_DEQUE
11#define _LIBCPP_DEQUE
12
13/*
14    deque synopsis
15
16namespace std
17{
18
19template <class T, class Allocator = allocator<T> >
20class deque
21{
22public:
23    // types:
24    typedef T value_type;
25    typedef Allocator allocator_type;
26
27    typedef typename allocator_type::reference       reference;
28    typedef typename allocator_type::const_reference const_reference;
29    typedef implementation-defined                   iterator;
30    typedef implementation-defined                   const_iterator;
31    typedef typename allocator_type::size_type       size_type;
32    typedef typename allocator_type::difference_type difference_type;
33
34    typedef typename allocator_type::pointer         pointer;
35    typedef typename allocator_type::const_pointer   const_pointer;
36    typedef std::reverse_iterator<iterator>          reverse_iterator;
37    typedef std::reverse_iterator<const_iterator>    const_reverse_iterator;
38
39    // construct/copy/destroy:
40    deque() noexcept(is_nothrow_default_constructible<allocator_type>::value);
41    explicit deque(const allocator_type& a);
42    explicit deque(size_type n);
43    explicit deque(size_type n, const allocator_type& a); // C++14
44    deque(size_type n, const value_type& v);
45    deque(size_type n, const value_type& v, const allocator_type& a);
46    template <class InputIterator>
47        deque(InputIterator f, InputIterator l);
48    template <class InputIterator>
49        deque(InputIterator f, InputIterator l, const allocator_type& a);
50    template<container-compatible-range<T> R>
51        deque(from_range_t, R&& rg, const Allocator& = Allocator()); // C++23
52    deque(const deque& c);
53    deque(deque&& c)
54        noexcept(is_nothrow_move_constructible<allocator_type>::value);
55    deque(initializer_list<value_type> il, const Allocator& a = allocator_type());
56    deque(const deque& c, const allocator_type& a);
57    deque(deque&& c, const allocator_type& a);
58    ~deque();
59
60    deque& operator=(const deque& c);
61    deque& operator=(deque&& c)
62        noexcept(
63             allocator_type::propagate_on_container_move_assignment::value &&
64             is_nothrow_move_assignable<allocator_type>::value);
65    deque& operator=(initializer_list<value_type> il);
66
67    template <class InputIterator>
68        void assign(InputIterator f, InputIterator l);
69    template<container-compatible-range<T> R>
70      void assign_range(R&& rg); // C++23
71    void assign(size_type n, const value_type& v);
72    void assign(initializer_list<value_type> il);
73
74    allocator_type get_allocator() const noexcept;
75
76    // iterators:
77
78    iterator       begin() noexcept;
79    const_iterator begin() const noexcept;
80    iterator       end() noexcept;
81    const_iterator end() const noexcept;
82
83    reverse_iterator       rbegin() noexcept;
84    const_reverse_iterator rbegin() const noexcept;
85    reverse_iterator       rend() noexcept;
86    const_reverse_iterator rend() const noexcept;
87
88    const_iterator         cbegin() const noexcept;
89    const_iterator         cend() const noexcept;
90    const_reverse_iterator crbegin() const noexcept;
91    const_reverse_iterator crend() const noexcept;
92
93    // capacity:
94    size_type size() const noexcept;
95    size_type max_size() const noexcept;
96    void resize(size_type n);
97    void resize(size_type n, const value_type& v);
98    void shrink_to_fit();
99    bool empty() const noexcept;
100
101    // element access:
102    reference operator[](size_type i);
103    const_reference operator[](size_type i) const;
104    reference at(size_type i);
105    const_reference at(size_type i) const;
106    reference front();
107    const_reference front() const;
108    reference back();
109    const_reference back() const;
110
111    // modifiers:
112    void push_front(const value_type& v);
113    void push_front(value_type&& v);
114    template<container-compatible-range<T> R>
115      void prepend_range(R&& rg); // C++23
116    void push_back(const value_type& v);
117    void push_back(value_type&& v);
118    template<container-compatible-range<T> R>
119      void append_range(R&& rg); // C++23
120    template <class... Args> reference emplace_front(Args&&... args);  // reference in C++17
121    template <class... Args> reference emplace_back(Args&&... args);   // reference in C++17
122    template <class... Args> iterator emplace(const_iterator p, Args&&... args);
123    iterator insert(const_iterator p, const value_type& v);
124    iterator insert(const_iterator p, value_type&& v);
125    iterator insert(const_iterator p, size_type n, const value_type& v);
126    template <class InputIterator>
127        iterator insert(const_iterator p, InputIterator f, InputIterator l);
128    template<container-compatible-range<T> R>
129      iterator insert_range(const_iterator position, R&& rg); // C++23
130    iterator insert(const_iterator p, initializer_list<value_type> il);
131    void pop_front();
132    void pop_back();
133    iterator erase(const_iterator p);
134    iterator erase(const_iterator f, const_iterator l);
135    void swap(deque& c)
136        noexcept(allocator_traits<allocator_type>::is_always_equal::value);  // C++17
137    void clear() noexcept;
138};
139
140template <class InputIterator, class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
141   deque(InputIterator, InputIterator, Allocator = Allocator())
142   -> deque<typename iterator_traits<InputIterator>::value_type, Allocator>; // C++17
143
144template<ranges::input_range R, class Allocator = allocator<ranges::range_value_t<R>>>
145  deque(from_range_t, R&&, Allocator = Allocator())
146    -> deque<ranges::range_value_t<R>, Allocator>; // C++23
147
148template <class T, class Allocator>
149    bool operator==(const deque<T,Allocator>& x, const deque<T,Allocator>& y);
150template <class T, class Allocator>
151    bool operator< (const deque<T,Allocator>& x, const deque<T,Allocator>& y); // removed in C++20
152template <class T, class Allocator>
153    bool operator!=(const deque<T,Allocator>& x, const deque<T,Allocator>& y); // removed in C++20
154template <class T, class Allocator>
155    bool operator> (const deque<T,Allocator>& x, const deque<T,Allocator>& y); // removed in C++20
156template <class T, class Allocator>
157    bool operator>=(const deque<T,Allocator>& x, const deque<T,Allocator>& y); // removed in C++20
158template <class T, class Allocator>
159    bool operator<=(const deque<T,Allocator>& x, const deque<T,Allocator>& y); // removed in C++20
160template<class T, class Allocator>
161    synth-three-way-result<T> operator<=>(const deque<T, Allocator>& x,
162                                          const deque<T, Allocator>& y);       // since C++20
163
164// specialized algorithms:
165template <class T, class Allocator>
166    void swap(deque<T,Allocator>& x, deque<T,Allocator>& y)
167         noexcept(noexcept(x.swap(y)));
168
169template <class T, class Allocator, class U>
170    typename deque<T, Allocator>::size_type
171    erase(deque<T, Allocator>& c, const U& value);       // C++20
172template <class T, class Allocator, class Predicate>
173    typename deque<T, Allocator>::size_type
174    erase_if(deque<T, Allocator>& c, Predicate pred);    // C++20
175
176}  // std
177
178*/
179
180#include <__algorithm/copy.h>
181#include <__algorithm/copy_backward.h>
182#include <__algorithm/copy_n.h>
183#include <__algorithm/equal.h>
184#include <__algorithm/fill_n.h>
185#include <__algorithm/lexicographical_compare.h>
186#include <__algorithm/lexicographical_compare_three_way.h>
187#include <__algorithm/min.h>
188#include <__algorithm/remove.h>
189#include <__algorithm/remove_if.h>
190#include <__algorithm/unwrap_iter.h>
191#include <__assert> // all public C++ headers provide the assertion handler
192#include <__availability>
193#include <__config>
194#include <__format/enable_insertable.h>
195#include <__iterator/distance.h>
196#include <__iterator/iterator_traits.h>
197#include <__iterator/next.h>
198#include <__iterator/prev.h>
199#include <__iterator/reverse_iterator.h>
200#include <__iterator/segmented_iterator.h>
201#include <__memory/addressof.h>
202#include <__memory/allocator_destructor.h>
203#include <__memory/pointer_traits.h>
204#include <__memory/temp_value.h>
205#include <__memory/unique_ptr.h>
206#include <__memory_resource/polymorphic_allocator.h>
207#include <__ranges/access.h>
208#include <__ranges/concepts.h>
209#include <__ranges/container_compatible_range.h>
210#include <__ranges/from_range.h>
211#include <__ranges/size.h>
212#include <__split_buffer>
213#include <__type_traits/is_allocator.h>
214#include <__type_traits/is_convertible.h>
215#include <__type_traits/is_same.h>
216#include <__type_traits/type_identity.h>
217#include <__utility/forward.h>
218#include <__utility/move.h>
219#include <__utility/pair.h>
220#include <__utility/swap.h>
221#include <limits>
222#include <stdexcept>
223#include <version>
224
225// standard-mandated includes
226
227// [iterator.range]
228#include <__iterator/access.h>
229#include <__iterator/data.h>
230#include <__iterator/empty.h>
231#include <__iterator/reverse_access.h>
232#include <__iterator/size.h>
233
234// [deque.syn]
235#include <compare>
236#include <initializer_list>
237
238#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
239#  pragma GCC system_header
240#endif
241
242_LIBCPP_PUSH_MACROS
243#include <__undef_macros>
244
245
246_LIBCPP_BEGIN_NAMESPACE_STD
247
248template <class _Tp, class _Allocator = allocator<_Tp> > class _LIBCPP_TEMPLATE_VIS deque;
249
250template <class _ValueType, class _DiffType>
251struct __deque_block_size {
252  static const _DiffType value = sizeof(_ValueType) < 256 ? 4096 / sizeof(_ValueType) : 16;
253};
254
255template <class _ValueType, class _Pointer, class _Reference, class _MapPointer,
256          class _DiffType, _DiffType _BS =
257#ifdef _LIBCPP_ABI_INCOMPLETE_TYPES_IN_DEQUE
258// Keep template parameter to avoid changing all template declarations thoughout
259// this file.
260                               0
261#else
262                               __deque_block_size<_ValueType, _DiffType>::value
263#endif
264          >
265class _LIBCPP_TEMPLATE_VIS __deque_iterator
266{
267    typedef _MapPointer __map_iterator;
268public:
269    typedef _Pointer  pointer;
270    typedef _DiffType difference_type;
271private:
272    __map_iterator __m_iter_;
273    pointer        __ptr_;
274
275    static const difference_type __block_size;
276public:
277    typedef _ValueType                  value_type;
278    typedef random_access_iterator_tag  iterator_category;
279    typedef _Reference                  reference;
280
281    _LIBCPP_HIDE_FROM_ABI __deque_iterator() _NOEXCEPT
282#if _LIBCPP_STD_VER >= 14
283     : __m_iter_(nullptr), __ptr_(nullptr)
284#endif
285     {}
286
287    template <class _Pp, class _Rp, class _MP>
288    _LIBCPP_HIDE_FROM_ABI
289    __deque_iterator(const __deque_iterator<value_type, _Pp, _Rp, _MP, difference_type, _BS>& __it,
290                typename enable_if<is_convertible<_Pp, pointer>::value>::type* = 0) _NOEXCEPT
291        : __m_iter_(__it.__m_iter_), __ptr_(__it.__ptr_) {}
292
293    _LIBCPP_HIDE_FROM_ABI reference operator*() const {return *__ptr_;}
294    _LIBCPP_HIDE_FROM_ABI pointer operator->() const {return __ptr_;}
295
296    _LIBCPP_HIDE_FROM_ABI __deque_iterator& operator++()
297    {
298        if (++__ptr_ - *__m_iter_ == __block_size)
299        {
300            ++__m_iter_;
301            __ptr_ = *__m_iter_;
302        }
303        return *this;
304    }
305
306    _LIBCPP_HIDE_FROM_ABI __deque_iterator operator++(int)
307    {
308        __deque_iterator __tmp = *this;
309        ++(*this);
310        return __tmp;
311    }
312
313    _LIBCPP_HIDE_FROM_ABI __deque_iterator& operator--()
314    {
315        if (__ptr_ == *__m_iter_)
316        {
317            --__m_iter_;
318            __ptr_ = *__m_iter_ + __block_size;
319        }
320        --__ptr_;
321        return *this;
322    }
323
324    _LIBCPP_HIDE_FROM_ABI __deque_iterator operator--(int)
325    {
326        __deque_iterator __tmp = *this;
327        --(*this);
328        return __tmp;
329    }
330
331    _LIBCPP_HIDE_FROM_ABI __deque_iterator& operator+=(difference_type __n)
332    {
333        if (__n != 0)
334        {
335            __n += __ptr_ - *__m_iter_;
336            if (__n > 0)
337            {
338                __m_iter_ += __n / __block_size;
339                __ptr_ = *__m_iter_ + __n % __block_size;
340            }
341            else // (__n < 0)
342            {
343                difference_type __z = __block_size - 1 - __n;
344                __m_iter_ -= __z / __block_size;
345                __ptr_ = *__m_iter_ + (__block_size - 1 - __z % __block_size);
346            }
347        }
348        return *this;
349    }
350
351    _LIBCPP_HIDE_FROM_ABI __deque_iterator& operator-=(difference_type __n)
352    {
353        return *this += -__n;
354    }
355
356    _LIBCPP_HIDE_FROM_ABI __deque_iterator operator+(difference_type __n) const
357    {
358        __deque_iterator __t(*this);
359        __t += __n;
360        return __t;
361    }
362
363    _LIBCPP_HIDE_FROM_ABI __deque_iterator operator-(difference_type __n) const
364    {
365        __deque_iterator __t(*this);
366        __t -= __n;
367        return __t;
368    }
369
370    _LIBCPP_HIDE_FROM_ABI
371    friend __deque_iterator operator+(difference_type __n, const __deque_iterator& __it)
372        {return __it + __n;}
373
374    _LIBCPP_HIDE_FROM_ABI
375    friend difference_type operator-(const __deque_iterator& __x, const __deque_iterator& __y)
376    {
377        if (__x != __y)
378            return (__x.__m_iter_ - __y.__m_iter_) * __block_size
379                 + (__x.__ptr_ - *__x.__m_iter_)
380                 - (__y.__ptr_ - *__y.__m_iter_);
381        return 0;
382    }
383
384    _LIBCPP_HIDE_FROM_ABI reference operator[](difference_type __n) const
385        {return *(*this + __n);}
386
387    _LIBCPP_HIDE_FROM_ABI friend
388        bool operator==(const __deque_iterator& __x, const __deque_iterator& __y)
389        {return __x.__ptr_ == __y.__ptr_;}
390
391    _LIBCPP_HIDE_FROM_ABI friend
392        bool operator!=(const __deque_iterator& __x, const __deque_iterator& __y)
393        {return !(__x == __y);}
394
395    _LIBCPP_HIDE_FROM_ABI friend
396        bool operator<(const __deque_iterator& __x, const __deque_iterator& __y)
397        {return __x.__m_iter_ < __y.__m_iter_ ||
398               (__x.__m_iter_ == __y.__m_iter_ && __x.__ptr_ < __y.__ptr_);}
399
400    _LIBCPP_HIDE_FROM_ABI friend
401        bool operator>(const __deque_iterator& __x, const __deque_iterator& __y)
402        {return __y < __x;}
403
404    _LIBCPP_HIDE_FROM_ABI friend
405        bool operator<=(const __deque_iterator& __x, const __deque_iterator& __y)
406        {return !(__y < __x);}
407
408    _LIBCPP_HIDE_FROM_ABI friend
409        bool operator>=(const __deque_iterator& __x, const __deque_iterator& __y)
410        {return !(__x < __y);}
411
412private:
413    _LIBCPP_HIDE_FROM_ABI explicit __deque_iterator(__map_iterator __m, pointer __p) _NOEXCEPT
414        : __m_iter_(__m), __ptr_(__p) {}
415
416    template <class _Tp, class _Ap> friend class _LIBCPP_TEMPLATE_VIS deque;
417    template <class _Vp, class _Pp, class _Rp, class _MP, class _Dp, _Dp>
418        friend class _LIBCPP_TEMPLATE_VIS __deque_iterator;
419
420    template <class>
421    friend struct __segmented_iterator_traits;
422};
423
424template <class _ValueType, class _Pointer, class _Reference, class _MapPointer, class _DiffType, _DiffType _BlockSize>
425struct __segmented_iterator_traits<
426    __deque_iterator<_ValueType, _Pointer, _Reference, _MapPointer, _DiffType, _BlockSize> > {
427private:
428  using _Iterator = __deque_iterator<_ValueType, _Pointer, _Reference, _MapPointer, _DiffType, _BlockSize>;
429
430public:
431  using __is_segmented_iterator = true_type;
432  using __segment_iterator = _MapPointer;
433  using __local_iterator = _Pointer;
434
435  static _LIBCPP_HIDE_FROM_ABI __segment_iterator __segment(_Iterator __iter) { return __iter.__m_iter_; }
436  static _LIBCPP_HIDE_FROM_ABI __local_iterator __local(_Iterator __iter) { return __iter.__ptr_; }
437  static _LIBCPP_HIDE_FROM_ABI __local_iterator __begin(__segment_iterator __iter) { return *__iter; }
438
439  static _LIBCPP_HIDE_FROM_ABI __local_iterator __end(__segment_iterator __iter) {
440        return *__iter + _Iterator::__block_size;
441  }
442
443  static _LIBCPP_HIDE_FROM_ABI _Iterator __compose(__segment_iterator __segment, __local_iterator __local) {
444        if (__local == __end(__segment)) {
445            ++__segment;
446            return _Iterator(__segment, *__segment);
447        }
448        return _Iterator(__segment, __local);
449  }
450};
451
452template <class _ValueType, class _Pointer, class _Reference, class _MapPointer,
453          class _DiffType, _DiffType _BlockSize>
454const _DiffType __deque_iterator<_ValueType, _Pointer, _Reference, _MapPointer,
455                                 _DiffType, _BlockSize>::__block_size =
456    __deque_block_size<_ValueType, _DiffType>::value;
457
458template <class _Tp, class _Allocator /*= allocator<_Tp>*/>
459class _LIBCPP_TEMPLATE_VIS deque
460{
461public:
462    // types:
463
464  using value_type = _Tp;
465
466  static_assert((is_same<typename _Allocator::value_type, value_type>::value),
467                "Allocator::value_type must be same type as value_type");
468
469  using allocator_type = _Allocator;
470  using __alloc_traits = allocator_traits<allocator_type>;
471
472  using size_type       = typename __alloc_traits::size_type;
473  using difference_type = typename __alloc_traits::difference_type;
474
475  using pointer       = typename __alloc_traits::pointer;
476  using const_pointer = typename __alloc_traits::const_pointer;
477
478  using __pointer_allocator       = __rebind_alloc<__alloc_traits, pointer>;
479  using __const_pointer_allocator = __rebind_alloc<__alloc_traits, const_pointer>;
480  using __map                     = __split_buffer<pointer, __pointer_allocator>;
481  using __map_alloc_traits        = allocator_traits<__pointer_allocator>;
482  using __map_pointer             = typename __map_alloc_traits::pointer;
483  using __map_const_pointer       = typename allocator_traits<__const_pointer_allocator>::const_pointer;
484  using __map_const_iterator      = typename __map::const_iterator;
485
486  using reference       = value_type&;
487  using const_reference = const value_type&;
488
489  using iterator = __deque_iterator<value_type, pointer, reference, __map_pointer, difference_type>;
490  using const_iterator =
491      __deque_iterator<value_type, const_pointer, const_reference, __map_const_pointer, difference_type>;
492  using reverse_iterator       = std::reverse_iterator<iterator>;
493  using const_reverse_iterator = std::reverse_iterator<const_iterator>;
494
495  static_assert(is_same<allocator_type, __rebind_alloc<__alloc_traits, value_type> >::value,
496                "[allocator.requirements] states that rebinding an allocator to the same type should result in the "
497                "original allocator");
498  static_assert(is_nothrow_default_constructible<allocator_type>::value ==
499                    is_nothrow_default_constructible<__pointer_allocator>::value,
500                "rebinding an allocator should not change excpetion guarantees");
501  static_assert(is_nothrow_move_constructible<allocator_type>::value ==
502                    is_nothrow_move_constructible<typename __map::allocator_type>::value,
503                "rebinding an allocator should not change excpetion guarantees");
504
505private:
506  struct __deque_block_range {
507    explicit _LIBCPP_HIDE_FROM_ABI
508    __deque_block_range(pointer __b, pointer __e) _NOEXCEPT : __begin_(__b), __end_(__e) {}
509    const pointer __begin_;
510    const pointer __end_;
511  };
512
513  struct __deque_range {
514    iterator __pos_;
515    const iterator __end_;
516
517    _LIBCPP_HIDE_FROM_ABI __deque_range(iterator __pos, iterator __e) _NOEXCEPT
518      : __pos_(__pos), __end_(__e) {}
519
520    explicit _LIBCPP_HIDE_FROM_ABI operator bool() const _NOEXCEPT {
521      return __pos_ != __end_;
522    }
523
524    _LIBCPP_HIDE_FROM_ABI __deque_range begin() const {
525      return *this;
526    }
527
528    _LIBCPP_HIDE_FROM_ABI __deque_range end() const {
529      return __deque_range(__end_, __end_);
530    }
531    _LIBCPP_HIDE_FROM_ABI __deque_block_range operator*() const _NOEXCEPT {
532        if (__pos_.__m_iter_ == __end_.__m_iter_) {
533        return __deque_block_range(__pos_.__ptr_, __end_.__ptr_);
534      }
535      return __deque_block_range(__pos_.__ptr_, *__pos_.__m_iter_ + __block_size);
536    }
537
538    _LIBCPP_HIDE_FROM_ABI __deque_range& operator++() _NOEXCEPT {
539      if (__pos_.__m_iter_ == __end_.__m_iter_) {
540        __pos_ = __end_;
541      } else {
542        ++__pos_.__m_iter_;
543        __pos_.__ptr_ = *__pos_.__m_iter_;
544      }
545      return *this;
546    }
547
548
549    _LIBCPP_HIDE_FROM_ABI friend bool operator==(__deque_range const& __lhs, __deque_range const& __rhs) {
550      return __lhs.__pos_ == __rhs.__pos_;
551    }
552    _LIBCPP_HIDE_FROM_ABI friend bool operator!=(__deque_range const& __lhs, __deque_range const& __rhs) {
553      return !(__lhs == __rhs);
554    }
555  };
556
557  struct _ConstructTransaction {
558    _LIBCPP_HIDE_FROM_ABI _ConstructTransaction(deque* __db, __deque_block_range& __r)
559      : __pos_(__r.__begin_), __end_(__r.__end_), __begin_(__r.__begin_), __base_(__db) {}
560
561
562    _LIBCPP_HIDE_FROM_ABI ~_ConstructTransaction() {
563      __base_->__size() += (__pos_ - __begin_);
564    }
565
566    pointer __pos_;
567    const pointer __end_;
568  private:
569    const pointer __begin_;
570    deque* const __base_;
571  };
572
573  static const difference_type __block_size;
574
575  __map __map_;
576  size_type __start_;
577  __compressed_pair<size_type, allocator_type> __size_;
578
579public:
580
581    // construct/copy/destroy:
582    _LIBCPP_HIDE_FROM_ABI
583    deque() _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
584        : __start_(0), __size_(0, __default_init_tag()) {
585      __annotate_new(0);
586    }
587
588    _LIBCPP_HIDE_FROM_ABI ~deque() {
589      clear();
590      __annotate_delete();
591      typename __map::iterator __i = __map_.begin();
592      typename __map::iterator __e = __map_.end();
593      for (; __i != __e; ++__i)
594          __alloc_traits::deallocate(__alloc(), *__i, __block_size);
595    }
596
597    _LIBCPP_HIDE_FROM_ABI explicit deque(const allocator_type& __a)
598        : __map_(__pointer_allocator(__a)), __start_(0), __size_(0, __a) {
599      __annotate_new(0);
600    }
601
602    explicit _LIBCPP_HIDE_FROM_ABI deque(size_type __n);
603#if _LIBCPP_STD_VER >= 14
604    explicit _LIBCPP_HIDE_FROM_ABI deque(size_type __n, const _Allocator& __a);
605#endif
606    _LIBCPP_HIDE_FROM_ABI deque(size_type __n, const value_type& __v);
607
608    template <class = __enable_if_t<__is_allocator<_Allocator>::value> >
609    _LIBCPP_HIDE_FROM_ABI deque(size_type __n, const value_type& __v, const allocator_type& __a)
610        : __map_(__pointer_allocator(__a)), __start_(0), __size_(0, __a)
611    {
612        __annotate_new(0);
613        if (__n > 0)
614            __append(__n, __v);
615    }
616
617    template <class _InputIter>
618    _LIBCPP_HIDE_FROM_ABI deque(_InputIter __f, _InputIter __l,
619              typename enable_if<__has_input_iterator_category<_InputIter>::value>::type* = 0);
620    template <class _InputIter>
621    _LIBCPP_HIDE_FROM_ABI deque(_InputIter __f, _InputIter __l, const allocator_type& __a,
622              typename enable_if<__has_input_iterator_category<_InputIter>::value>::type* = 0);
623
624#if _LIBCPP_STD_VER >= 23
625  template <_ContainerCompatibleRange<_Tp> _Range>
626  _LIBCPP_HIDE_FROM_ABI deque(from_range_t, _Range&& __range,
627      const allocator_type& __a = allocator_type())
628    : __map_(__pointer_allocator(__a)), __start_(0), __size_(0, __a) {
629    if constexpr (ranges::forward_range<_Range> || ranges::sized_range<_Range>) {
630      __append_with_size(ranges::begin(__range), ranges::distance(__range));
631
632    } else {
633      for (auto&& __e : __range) {
634        emplace_back(std::forward<decltype(__e)>(__e));
635      }
636    }
637  }
638#endif
639
640    _LIBCPP_HIDE_FROM_ABI deque(const deque& __c);
641    _LIBCPP_HIDE_FROM_ABI deque(const deque& __c, const __type_identity_t<allocator_type>& __a);
642
643    _LIBCPP_HIDE_FROM_ABI deque& operator=(const deque& __c);
644
645#ifndef _LIBCPP_CXX03_LANG
646    _LIBCPP_HIDE_FROM_ABI deque(initializer_list<value_type> __il);
647    _LIBCPP_HIDE_FROM_ABI deque(initializer_list<value_type> __il, const allocator_type& __a);
648
649    _LIBCPP_HIDE_FROM_ABI
650    deque& operator=(initializer_list<value_type> __il) {assign(__il); return *this;}
651
652    _LIBCPP_HIDE_FROM_ABI
653    deque(deque&& __c) _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value);
654    _LIBCPP_HIDE_FROM_ABI
655    deque(deque&& __c, const __type_identity_t<allocator_type>& __a);
656    _LIBCPP_HIDE_FROM_ABI
657    deque& operator=(deque&& __c)
658        _NOEXCEPT_(__alloc_traits::propagate_on_container_move_assignment::value &&
659                   is_nothrow_move_assignable<allocator_type>::value);
660
661    _LIBCPP_HIDE_FROM_ABI
662    void assign(initializer_list<value_type> __il) {assign(__il.begin(), __il.end());}
663#endif // _LIBCPP_CXX03_LANG
664
665    template <class _InputIter>
666    _LIBCPP_HIDE_FROM_ABI void assign(_InputIter __f, _InputIter __l,
667                    typename enable_if<__has_input_iterator_category<_InputIter>::value &&
668                                      !__has_random_access_iterator_category<_InputIter>::value>::type* = 0);
669    template <class _RAIter>
670    _LIBCPP_HIDE_FROM_ABI void assign(_RAIter __f, _RAIter __l,
671                    typename enable_if<__has_random_access_iterator_category<_RAIter>::value>::type* = 0);
672
673#if _LIBCPP_STD_VER >= 23
674    template <_ContainerCompatibleRange<_Tp> _Range>
675    _LIBCPP_HIDE_FROM_ABI
676    void assign_range(_Range&& __range) {
677      if constexpr (ranges::random_access_range<_Range>) {
678        auto __n = static_cast<size_type>(ranges::distance(__range));
679        __assign_with_size_random_access(ranges::begin(__range), __n);
680
681      } else if constexpr (ranges::forward_range<_Range> || ranges::sized_range<_Range>) {
682        auto __n = static_cast<size_type>(ranges::distance(__range));
683        __assign_with_size(ranges::begin(__range), __n);
684
685      } else {
686        __assign_with_sentinel(ranges::begin(__range), ranges::end(__range));
687      }
688    }
689#endif
690
691    _LIBCPP_HIDE_FROM_ABI void assign(size_type __n, const value_type& __v);
692
693    _LIBCPP_HIDE_FROM_ABI
694    allocator_type get_allocator() const _NOEXCEPT;
695  _LIBCPP_HIDE_FROM_ABI allocator_type& __alloc() _NOEXCEPT { return __size_.second(); }
696  _LIBCPP_HIDE_FROM_ABI const allocator_type& __alloc() const _NOEXCEPT { return __size_.second(); }
697
698  // iterators:
699
700  _LIBCPP_HIDE_FROM_ABI iterator begin() _NOEXCEPT {
701      __map_pointer __mp = __map_.begin() + __start_ / __block_size;
702      return iterator(__mp, __map_.empty() ? 0 : *__mp + __start_ % __block_size);
703  }
704
705  _LIBCPP_HIDE_FROM_ABI const_iterator begin() const _NOEXCEPT {
706      __map_const_pointer __mp =
707          static_cast<__map_const_pointer>(__map_.begin() + __start_ / __block_size);
708      return const_iterator(__mp, __map_.empty() ? 0 : *__mp + __start_ % __block_size);
709  }
710
711  _LIBCPP_HIDE_FROM_ABI iterator end() _NOEXCEPT {
712      size_type __p      = size() + __start_;
713      __map_pointer __mp = __map_.begin() + __p / __block_size;
714      return iterator(__mp, __map_.empty() ? 0 : *__mp + __p % __block_size);
715  }
716
717  _LIBCPP_HIDE_FROM_ABI const_iterator end() const _NOEXCEPT {
718      size_type __p            = size() + __start_;
719      __map_const_pointer __mp = static_cast<__map_const_pointer>(__map_.begin() + __p / __block_size);
720      return const_iterator(__mp, __map_.empty() ? 0 : *__mp + __p % __block_size);
721  }
722
723    _LIBCPP_HIDE_FROM_ABI
724    reverse_iterator       rbegin() _NOEXCEPT
725        {return       reverse_iterator(end());}
726    _LIBCPP_HIDE_FROM_ABI
727    const_reverse_iterator rbegin() const _NOEXCEPT
728        {return const_reverse_iterator(end());}
729    _LIBCPP_HIDE_FROM_ABI
730    reverse_iterator       rend() _NOEXCEPT
731        {return       reverse_iterator(begin());}
732    _LIBCPP_HIDE_FROM_ABI
733    const_reverse_iterator rend()   const _NOEXCEPT
734        {return const_reverse_iterator(begin());}
735
736    _LIBCPP_HIDE_FROM_ABI
737    const_iterator         cbegin()  const _NOEXCEPT
738        {return begin();}
739    _LIBCPP_HIDE_FROM_ABI
740    const_iterator         cend()    const _NOEXCEPT
741        {return end();}
742    _LIBCPP_HIDE_FROM_ABI
743    const_reverse_iterator crbegin() const _NOEXCEPT
744        {return const_reverse_iterator(end());}
745    _LIBCPP_HIDE_FROM_ABI
746    const_reverse_iterator crend()   const _NOEXCEPT
747        {return const_reverse_iterator(begin());}
748
749    // capacity:
750    _LIBCPP_HIDE_FROM_ABI
751    size_type size() const _NOEXCEPT {return __size();}
752
753  _LIBCPP_HIDE_FROM_ABI size_type& __size() _NOEXCEPT { return __size_.first(); }
754  _LIBCPP_HIDE_FROM_ABI const size_type& __size() const _NOEXCEPT { return __size_.first(); }
755
756    _LIBCPP_HIDE_FROM_ABI
757    size_type max_size() const _NOEXCEPT
758        {return _VSTD::min<size_type>(
759            __alloc_traits::max_size(__alloc()),
760            numeric_limits<difference_type>::max());}
761    _LIBCPP_HIDE_FROM_ABI void resize(size_type __n);
762    _LIBCPP_HIDE_FROM_ABI void resize(size_type __n, const value_type& __v);
763    _LIBCPP_HIDE_FROM_ABI void shrink_to_fit() _NOEXCEPT;
764    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_HIDE_FROM_ABI
765    bool empty() const _NOEXCEPT {return size() == 0;}
766
767    // element access:
768    _LIBCPP_HIDE_FROM_ABI
769    reference operator[](size_type __i) _NOEXCEPT;
770    _LIBCPP_HIDE_FROM_ABI
771    const_reference operator[](size_type __i) const _NOEXCEPT;
772    _LIBCPP_HIDE_FROM_ABI
773    reference at(size_type __i);
774    _LIBCPP_HIDE_FROM_ABI
775    const_reference at(size_type __i) const;
776    _LIBCPP_HIDE_FROM_ABI
777    reference front() _NOEXCEPT;
778    _LIBCPP_HIDE_FROM_ABI
779    const_reference front() const _NOEXCEPT;
780    _LIBCPP_HIDE_FROM_ABI
781    reference back() _NOEXCEPT;
782    _LIBCPP_HIDE_FROM_ABI
783    const_reference back() const _NOEXCEPT;
784
785    // 23.2.2.3 modifiers:
786    _LIBCPP_HIDE_FROM_ABI void push_front(const value_type& __v);
787    _LIBCPP_HIDE_FROM_ABI void push_back(const value_type& __v);
788#ifndef _LIBCPP_CXX03_LANG
789#if _LIBCPP_STD_VER >= 17
790    template <class... _Args> _LIBCPP_HIDE_FROM_ABI reference emplace_front(_Args&&... __args);
791    template <class... _Args> _LIBCPP_HIDE_FROM_ABI reference emplace_back (_Args&&... __args);
792#else
793    template <class... _Args> _LIBCPP_HIDE_FROM_ABI void      emplace_front(_Args&&... __args);
794    template <class... _Args> _LIBCPP_HIDE_FROM_ABI void      emplace_back (_Args&&... __args);
795#endif
796    template <class... _Args> _LIBCPP_HIDE_FROM_ABI iterator emplace(const_iterator __p, _Args&&... __args);
797
798    _LIBCPP_HIDE_FROM_ABI void push_front(value_type&& __v);
799    _LIBCPP_HIDE_FROM_ABI void push_back(value_type&& __v);
800
801#if _LIBCPP_STD_VER >= 23
802    template <_ContainerCompatibleRange<_Tp> _Range>
803    _LIBCPP_HIDE_FROM_ABI
804    void prepend_range(_Range&& __range) {
805      insert_range(begin(), std::forward<_Range>(__range));
806    }
807
808    template <_ContainerCompatibleRange<_Tp> _Range>
809    _LIBCPP_HIDE_FROM_ABI
810    void append_range(_Range&& __range) {
811      insert_range(end(), std::forward<_Range>(__range));
812    }
813#endif
814
815    _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, value_type&& __v);
816
817    _LIBCPP_HIDE_FROM_ABI
818    iterator insert(const_iterator __p, initializer_list<value_type> __il)
819        {return insert(__p, __il.begin(), __il.end());}
820#endif // _LIBCPP_CXX03_LANG
821    _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, const value_type& __v);
822    _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, size_type __n, const value_type& __v);
823    template <class _InputIter>
824    _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, _InputIter __f, _InputIter __l,
825                         typename enable_if<__has_exactly_input_iterator_category<_InputIter>::value>::type* = 0);
826    template <class _ForwardIterator>
827    _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, _ForwardIterator __f, _ForwardIterator __l,
828                        typename enable_if<__has_exactly_forward_iterator_category<_ForwardIterator>::value>::type* = 0);
829    template <class _BiIter>
830    _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, _BiIter __f, _BiIter __l,
831                         typename enable_if<__has_bidirectional_iterator_category<_BiIter>::value>::type* = 0);
832
833#if _LIBCPP_STD_VER >= 23
834    template <_ContainerCompatibleRange<_Tp> _Range>
835    _LIBCPP_HIDE_FROM_ABI
836    iterator insert_range(const_iterator __position, _Range&& __range) {
837      if constexpr (ranges::bidirectional_range<_Range>) {
838        auto __n = static_cast<size_type>(ranges::distance(__range));
839        return __insert_bidirectional(__position, ranges::begin(__range), ranges::end(__range), __n);
840
841      } else if constexpr (ranges::forward_range<_Range> || ranges::sized_range<_Range>) {
842        auto __n = static_cast<size_type>(ranges::distance(__range));
843        return __insert_with_size(__position, ranges::begin(__range), __n);
844
845      } else {
846        return __insert_with_sentinel(__position, ranges::begin(__range), ranges::end(__range));
847      }
848    }
849#endif
850
851    _LIBCPP_HIDE_FROM_ABI void pop_front();
852    _LIBCPP_HIDE_FROM_ABI void pop_back();
853    _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __p);
854    _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __f, const_iterator __l);
855
856    _LIBCPP_HIDE_FROM_ABI
857    void swap(deque& __c)
858#if _LIBCPP_STD_VER >= 14
859        _NOEXCEPT;
860#else
861        _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value ||
862                   __is_nothrow_swappable<allocator_type>::value);
863#endif
864    _LIBCPP_HIDE_FROM_ABI
865    void clear() _NOEXCEPT;
866
867    _LIBCPP_HIDE_FROM_ABI
868    bool __invariants() const {
869        if (!__map_.__invariants())
870            return false;
871        if (__map_.size() >= size_type(-1) / __block_size)
872            return false;
873        for (__map_const_iterator __i = __map_.begin(), __e = __map_.end();
874            __i != __e; ++__i)
875            if (*__i == nullptr)
876                return false;
877        if (__map_.size() != 0)
878        {
879            if (size() >= __map_.size() * __block_size)
880                return false;
881            if (__start_ >= __map_.size() * __block_size - size())
882                return false;
883        }
884        else
885        {
886            if (size() != 0)
887                return false;
888            if (__start_ != 0)
889                return false;
890        }
891        return true;
892    }
893
894    _LIBCPP_HIDE_FROM_ABI
895    void __move_assign_alloc(deque& __c)
896        _NOEXCEPT_(!__alloc_traits::propagate_on_container_move_assignment::value ||
897                   is_nothrow_move_assignable<allocator_type>::value)
898        {__move_assign_alloc(__c, integral_constant<bool,
899                      __alloc_traits::propagate_on_container_move_assignment::value>());}
900
901    _LIBCPP_HIDE_FROM_ABI
902    void __move_assign_alloc(deque& __c, true_type)
903        _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
904        {
905            __alloc() = _VSTD::move(__c.__alloc());
906        }
907
908    _LIBCPP_HIDE_FROM_ABI
909    void __move_assign_alloc(deque&, false_type) _NOEXCEPT
910        {}
911
912    _LIBCPP_HIDE_FROM_ABI
913    void __move_assign(deque& __c)
914        _NOEXCEPT_(__alloc_traits::propagate_on_container_move_assignment::value &&
915                   is_nothrow_move_assignable<allocator_type>::value)
916    {
917        __map_ = _VSTD::move(__c.__map_);
918        __start_ = __c.__start_;
919        __size() = __c.size();
920        __move_assign_alloc(__c);
921        __c.__start_ = __c.__size() = 0;
922    }
923
924    _LIBCPP_HIDE_FROM_ABI
925    static size_type __recommend_blocks(size_type __n)
926    {
927        return __n / __block_size + (__n % __block_size != 0);
928    }
929    _LIBCPP_HIDE_FROM_ABI
930    size_type __capacity() const
931    {
932        return __map_.size() == 0 ? 0 : __map_.size() * __block_size - 1;
933    }
934    _LIBCPP_HIDE_FROM_ABI
935    size_type __block_count() const
936    {
937        return __map_.size();
938    }
939
940    _LIBCPP_HIDE_FROM_ABI
941    size_type __front_spare() const
942    {
943        return __start_;
944    }
945    _LIBCPP_HIDE_FROM_ABI
946    size_type __front_spare_blocks() const {
947      return __front_spare() / __block_size;
948    }
949    _LIBCPP_HIDE_FROM_ABI
950    size_type __back_spare() const
951    {
952        return __capacity() - (__start_ + size());
953    }
954    _LIBCPP_HIDE_FROM_ABI
955    size_type __back_spare_blocks() const {
956      return __back_spare() / __block_size;
957    }
958
959 private:
960   enum __asan_annotation_type {
961     __asan_unposion,
962     __asan_poison
963   };
964
965   enum __asan_annotation_place {
966     __asan_front_moved,
967     __asan_back_moved,
968   };
969
970// The following functions are no-ops outside of AddressSanitizer mode.
971// We call annotations for every allocator, unless explicitly disabled.
972//
973// To disable annotations for a particular allocator, change value of
974// __asan_annotate_container_with_allocator to false.
975// For more details, see the "Using libc++" documentation page or
976// the documentation for __sanitizer_annotate_contiguous_container.
977#if !defined(_LIBCPP_HAS_NO_ASAN) && _LIBCPP_CLANG_VER >= 1600
978    // TODO LLVM18: Remove the special-casing
979    _LIBCPP_HIDE_FROM_ABI void __annotate_double_ended_contiguous_container(
980        const void* __beg,
981        const void* __end,
982        const void* __old_con_beg,
983        const void* __old_con_end,
984        const void* __new_con_beg,
985        const void* __new_con_end) const {
986        if (__beg != nullptr && __asan_annotate_container_with_allocator<_Allocator>::value)
987            __sanitizer_annotate_double_ended_contiguous_container(
988                __beg, __end, __old_con_beg, __old_con_end, __new_con_beg, __new_con_end);
989    }
990#else
991    _LIBCPP_HIDE_FROM_ABI void __annotate_double_ended_contiguous_container(
992        const void*, const void*, const void*, const void*, const void*, const void*) const _NOEXCEPT {}
993#endif // !defined(_LIBCPP_HAS_NO_ASAN) && _LIBCPP_CLANG_VER >= 1600
994
995    _LIBCPP_HIDE_FROM_ABI
996    void __annotate_from_to(size_type __beg, size_type __end, __asan_annotation_type __annotation_type, __asan_annotation_place __place) const _NOEXCEPT {
997        // __beg - index of the first item to annotate
998        // __end - index behind the last item to annotate (so last item + 1)
999        // __annotation_type - __asan_unposion or __asan_poison
1000        // __place - __asan_front_moved or __asan_back_moved
1001        // Note: All indexes in __map_
1002        if (__beg == __end)
1003            return;
1004        // __annotations_beg_map - first chunk which annotations we want to modify
1005        // __annotations_end_map - last chunk which annotations we want to modify
1006        // NOTE: if __end % __block_size == 0, __annotations_end_map points at the next block, which may not exist
1007        __map_const_iterator __annotations_beg_map = __map_.begin() + __beg / __block_size;
1008        __map_const_iterator __annotations_end_map = __map_.begin() + __end / __block_size;
1009
1010        bool const __poisoning = __annotation_type == __asan_poison;
1011        // __old_c_beg_index - index of the first element in old container
1012        // __old_c_end_index - index of the end of old container (last + 1)
1013        // Note: may be outside the area we are annotating
1014        size_t __old_c_beg_index = (__poisoning && __place == __asan_front_moved) ? __beg : __start_;
1015        size_t __old_c_end_index = (__poisoning && __place == __asan_back_moved)  ? __end : __start_ + size();
1016        bool const __front = __place == __asan_front_moved;
1017
1018        if (__poisoning && empty()) {
1019            // Special case: we shouldn't trust __start_
1020            __old_c_beg_index = __beg;
1021            __old_c_end_index = __end;
1022        }
1023        // __old_c_beg_map - memory block (chunk) with first element
1024        // __old_c_end_map - memory block (chunk) with end of old container
1025        // Note: if __old_c_end_index % __block_size == 0, __old_c_end_map points at the next block,
1026        // which may not exist
1027        __map_const_iterator __old_c_beg_map = __map_.begin() + __old_c_beg_index / __block_size;
1028        __map_const_iterator __old_c_end_map = __map_.begin() + __old_c_end_index / __block_size;
1029
1030        // One edge (front/end) of the container was moved and one was not modified.
1031        // __new_edge_index - index of new edge
1032        // __new_edge_map    - memory block (chunk) with new edge, it always equals to
1033        //                    __annotations_beg_map or __annotations_end_map
1034        // __old_edge_map    - memory block (chunk) with old edge, it always equals to
1035        //                    __old_c_beg_map or __old_c_end_map
1036        size_t __new_edge_index                      = (__poisoning ^ __front) ? __beg : __end;
1037        __map_const_iterator __new_edge_map = __map_.begin() + __new_edge_index / __block_size;
1038        __map_const_iterator __old_edge_map = __front ? __old_c_end_map : __old_c_beg_map;
1039
1040        // We iterate over map pointers (chunks) and fully poison all memory blocks between the first and the last.
1041        // First and last chunk may be partially poisoned.
1042        // __annotate_end_map may point at not existing chunk, therefore we have to have a check for it.
1043        for (__map_const_iterator __map_it = __annotations_beg_map; __map_it <= __annotations_end_map; ++__map_it) {
1044            if (__map_it == __annotations_end_map && __end % __block_size == 0)
1045                // Chunk may not exist, but nothing to do here anyway
1046                break;
1047
1048            // The beginning and the end of the current memory block
1049            const void* __mem_beg = std::__to_address(*__map_it);
1050            const void* __mem_end = std::__to_address(*__map_it + __block_size);
1051
1052            // The beginning of memory-in-use in the memory block before container modification
1053            const void* __old_beg =
1054                (__map_it == __old_c_beg_map) ? std::__to_address(*__map_it + (__old_c_beg_index % __block_size)) : __mem_beg;
1055
1056            // The end of memory-in-use in the memory block before container modification
1057            const void* __old_end;
1058            if (__map_it < __old_c_beg_map || __map_it > __old_c_end_map || (!__poisoning && empty()))
1059                __old_end = __old_beg;
1060            else
1061                __old_end = (__map_it == __old_c_end_map) ? std::__to_address(*__map_it + (__old_c_end_index % __block_size))
1062                                                   : __mem_end;
1063
1064            // New edge of the container in current memory block
1065            // If the edge is in a different chunk it points on corresponding end of the memory block
1066            const void* __new_edge;
1067            if (__map_it == __new_edge_map)
1068                __new_edge = std::__to_address(*__map_it + (__new_edge_index % __block_size));
1069            else
1070                __new_edge = (__poisoning ^ __front) ? __mem_beg : __mem_end;
1071
1072            // Not modified edge of the container
1073            // If the edge is in a different chunk it points on corresponding end of the memory block
1074            const void* __old_edge;
1075            if (__map_it == __old_edge_map)
1076                __old_edge = __front ? __old_end : __old_beg;
1077            else
1078                __old_edge = __front ? __mem_end : __mem_beg;
1079
1080            // __new_beg - the beginning of memory-in-use in the memory block after container modification
1081            // __new_end - the end of memory-in-use in the memory block after container modification
1082            const void* __new_beg = __front ? __new_edge : __old_edge;
1083            const void* __new_end = __front ? __old_edge : __new_edge;
1084
1085            __annotate_double_ended_contiguous_container(__mem_beg, __mem_end, __old_beg, __old_end, __new_beg, __new_end);
1086        }
1087    }
1088
1089    _LIBCPP_HIDE_FROM_ABI
1090    void __annotate_new(size_type __current_size) const _NOEXCEPT {
1091        if (__current_size == 0)
1092            __annotate_from_to(0, __map_.size() * __block_size, __asan_poison, __asan_back_moved);
1093        else {
1094            __annotate_from_to(0, __start_, __asan_poison, __asan_front_moved);
1095            __annotate_from_to(__start_ + __current_size, __map_.size() * __block_size, __asan_poison, __asan_back_moved);
1096        }
1097    }
1098
1099    _LIBCPP_HIDE_FROM_ABI
1100    void __annotate_delete() const _NOEXCEPT {
1101        if (empty()) {
1102            for(size_t __i = 0; __i < __map_.size(); ++__i) {
1103                __annotate_whole_block(__i, __asan_unposion);
1104            }
1105        }
1106        else {
1107            __annotate_from_to(0, __start_, __asan_unposion, __asan_front_moved);
1108            __annotate_from_to(__start_ + size(), __map_.size() * __block_size, __asan_unposion, __asan_back_moved);
1109        }
1110    }
1111
1112    _LIBCPP_HIDE_FROM_ABI
1113    void __annotate_increase_front(size_type __n) const _NOEXCEPT {
1114        __annotate_from_to(__start_ - __n, __start_, __asan_unposion, __asan_front_moved);
1115    }
1116
1117    _LIBCPP_HIDE_FROM_ABI
1118    void __annotate_increase_back(size_type __n) const _NOEXCEPT {
1119        __annotate_from_to(__start_ + size(), __start_ + size() + __n, __asan_unposion, __asan_back_moved);
1120    }
1121
1122    _LIBCPP_HIDE_FROM_ABI
1123    void __annotate_shrink_front(size_type __old_size, size_type __old_start) const _NOEXCEPT {
1124        __annotate_from_to(__old_start, __old_start + (__old_size - size()), __asan_poison, __asan_front_moved);
1125    }
1126
1127    _LIBCPP_HIDE_FROM_ABI
1128    void __annotate_shrink_back(size_type __old_size, size_type __old_start) const _NOEXCEPT {
1129        __annotate_from_to(__old_start + size(), __old_start + __old_size, __asan_poison, __asan_back_moved);
1130    }
1131
1132    _LIBCPP_HIDE_FROM_ABI
1133    void __annotate_poison_block(const void *__beginning, const void *__end) const _NOEXCEPT {
1134        __annotate_double_ended_contiguous_container(__beginning, __end, __beginning, __end, __end, __end);
1135    }
1136
1137    _LIBCPP_HIDE_FROM_ABI
1138    void __annotate_whole_block(size_t __block_index, __asan_annotation_type __annotation_type) const _NOEXCEPT {
1139        __map_const_iterator __block_it = __map_.begin() + __block_index;
1140        const void* __block_start = std::__to_address(*__block_it);
1141        const void* __block_end = std::__to_address(*__block_it + __block_size);
1142
1143        if(__annotation_type == __asan_poison)
1144            __annotate_poison_block(__block_start, __block_end);
1145        else {
1146            __annotate_double_ended_contiguous_container(
1147                __block_start, __block_end, __block_start, __block_start, __block_start, __block_end);
1148        }
1149    }
1150#if !defined(_LIBCPP_HAS_NO_ASAN)
1151
1152  public:
1153    _LIBCPP_HIDE_FROM_ABI
1154    bool __verify_asan_annotations() const _NOEXCEPT {
1155        // This function tests deque object annotations.
1156        if (empty()) {
1157            for (__map_const_iterator __it = __map_.begin(); __it != __map_.end(); ++__it) {
1158                if (!__sanitizer_verify_double_ended_contiguous_container(
1159                        std::__to_address(*__it),
1160                        std::__to_address(*__it),
1161                        std::__to_address(*__it),
1162                        std::__to_address(*__it + __block_size)))
1163                  return false;
1164            }
1165
1166            return true;
1167        }
1168
1169        size_type __end                           = __start_ + size();
1170        __map_const_iterator __first_mp = __map_.begin() + __start_ / __block_size;
1171        __map_const_iterator __last_mp  = __map_.begin() + (__end - 1) / __block_size;
1172
1173        // Pointers to first and after last elements
1174        // Those can be in different deque blocks
1175        const void* __p_beg = std::__to_address(*__first_mp + (__start_ % __block_size));
1176        const void* __p_end =
1177            std::__to_address(*__last_mp + ((__end % __block_size == 0) ? __block_size : __end % __block_size));
1178
1179        for (__map_const_iterator __it = __map_.begin(); __it != __map_.end(); ++__it) {
1180            // Go over all blocks, find the place we are in and verify its annotations
1181            // Note that __p_end points *behind* the last item.
1182
1183            // - blocks before the first block with container elements
1184            // - first block with items
1185            // - last block with items
1186            // - blocks after last block with ciontainer elements
1187
1188            // Is the block before or after deque blocks that contain elements?
1189            if (__it < __first_mp || __it > __last_mp) {
1190                if (!__sanitizer_verify_double_ended_contiguous_container(
1191                        std::__to_address(*__it),
1192                        std::__to_address(*__it),
1193                        std::__to_address(*__it),
1194                        std::__to_address(*__it + __block_size)))
1195                  return false;
1196            } else {
1197                const void* __containers_buffer_beg = (__it == __first_mp) ? __p_beg : (const void*)std::__to_address(*__it);
1198                const void* __containers_buffer_end =
1199                    (__it == __last_mp) ? __p_end : (const void*)std::__to_address(*__it + __block_size);
1200                if (!__sanitizer_verify_double_ended_contiguous_container(
1201                        std::__to_address(*__it),
1202                        __containers_buffer_beg,
1203                        __containers_buffer_end,
1204                        std::__to_address(*__it + __block_size))) {
1205                  return false;
1206                }
1207            }
1208        }
1209        return true;
1210    }
1211
1212  private:
1213#endif // _LIBCPP_VERIFY_ASAN_DEQUE_ANNOTATIONS
1214    _LIBCPP_HIDE_FROM_ABI
1215    bool __maybe_remove_front_spare(bool __keep_one = true) {
1216      if (__front_spare_blocks() >= 2 || (!__keep_one && __front_spare_blocks())) {
1217        __annotate_whole_block(0, __asan_unposion);
1218        __alloc_traits::deallocate(__alloc(), __map_.front(),
1219                                   __block_size);
1220        __map_.pop_front();
1221        __start_ -= __block_size;
1222        return true;
1223      }
1224      return false;
1225    }
1226
1227    _LIBCPP_HIDE_FROM_ABI
1228    bool __maybe_remove_back_spare(bool __keep_one = true) {
1229      if (__back_spare_blocks() >= 2 || (!__keep_one && __back_spare_blocks())) {
1230        __annotate_whole_block(__map_.size() - 1, __asan_unposion);
1231        __alloc_traits::deallocate(__alloc(), __map_.back(),
1232                                   __block_size);
1233        __map_.pop_back();
1234        return true;
1235      }
1236      return false;
1237    }
1238
1239    template <class _Iterator, class _Sentinel>
1240    _LIBCPP_HIDE_FROM_ABI
1241    void __assign_with_sentinel(_Iterator __f, _Sentinel __l);
1242
1243    template <class _RandomAccessIterator>
1244    _LIBCPP_HIDE_FROM_ABI
1245    void __assign_with_size_random_access(_RandomAccessIterator __f, difference_type __n);
1246    template <class _Iterator>
1247    _LIBCPP_HIDE_FROM_ABI
1248    void __assign_with_size(_Iterator __f, difference_type __n);
1249
1250    template <class _Iterator, class _Sentinel>
1251    _LIBCPP_HIDE_FROM_ABI
1252    iterator __insert_with_sentinel(const_iterator __p, _Iterator __f, _Sentinel __l);
1253
1254    template <class _Iterator>
1255    _LIBCPP_HIDE_FROM_ABI
1256    iterator __insert_with_size(const_iterator __p, _Iterator __f, size_type __n);
1257
1258    template <class _BiIter, class _Sentinel>
1259    _LIBCPP_HIDE_FROM_ABI
1260    iterator __insert_bidirectional(const_iterator __p, _BiIter __f, _Sentinel __sent, size_type __n);
1261    template <class _BiIter>
1262    _LIBCPP_HIDE_FROM_ABI
1263    iterator __insert_bidirectional(const_iterator __p, _BiIter __f, _BiIter __l, size_type __n);
1264
1265    template <class _InpIter>
1266    _LIBCPP_HIDE_FROM_ABI void __append(_InpIter __f, _InpIter __l,
1267                 typename enable_if<__has_exactly_input_iterator_category<_InpIter>::value>::type* = 0);
1268    template <class _ForIter>
1269    _LIBCPP_HIDE_FROM_ABI void __append(_ForIter __f, _ForIter __l,
1270                      typename enable_if<__has_forward_iterator_category<_ForIter>::value>::type* = 0);
1271
1272    template <class _InputIterator>
1273    _LIBCPP_HIDE_FROM_ABI void __append_with_size(_InputIterator __from, size_type __n);
1274    template <class _InputIterator, class _Sentinel>
1275    _LIBCPP_HIDE_FROM_ABI void __append_with_sentinel(_InputIterator __f, _Sentinel __l);
1276
1277    _LIBCPP_HIDE_FROM_ABI void __append(size_type __n);
1278    _LIBCPP_HIDE_FROM_ABI void __append(size_type __n, const value_type& __v);
1279    _LIBCPP_HIDE_FROM_ABI void __erase_to_end(const_iterator __f);
1280    _LIBCPP_HIDE_FROM_ABI void __add_front_capacity();
1281    _LIBCPP_HIDE_FROM_ABI void __add_front_capacity(size_type __n);
1282    _LIBCPP_HIDE_FROM_ABI void __add_back_capacity();
1283    _LIBCPP_HIDE_FROM_ABI void __add_back_capacity(size_type __n);
1284    _LIBCPP_HIDE_FROM_ABI iterator __move_and_check(iterator __f, iterator __l, iterator __r,
1285                              const_pointer& __vt);
1286    _LIBCPP_HIDE_FROM_ABI iterator __move_backward_and_check(iterator __f, iterator __l, iterator __r,
1287                                       const_pointer& __vt);
1288    _LIBCPP_HIDE_FROM_ABI void __move_construct_and_check(iterator __f, iterator __l,
1289                                    iterator __r, const_pointer& __vt);
1290    _LIBCPP_HIDE_FROM_ABI void __move_construct_backward_and_check(iterator __f, iterator __l,
1291                                             iterator __r, const_pointer& __vt);
1292
1293    _LIBCPP_HIDE_FROM_ABI
1294    void __copy_assign_alloc(const deque& __c)
1295        {__copy_assign_alloc(__c, integral_constant<bool,
1296                      __alloc_traits::propagate_on_container_copy_assignment::value>());}
1297
1298    _LIBCPP_HIDE_FROM_ABI
1299    void __copy_assign_alloc(const deque& __c, true_type)
1300        {
1301            if (__alloc() != __c.__alloc())
1302            {
1303                clear();
1304                shrink_to_fit();
1305            }
1306            __alloc() = __c.__alloc();
1307            __map_.__alloc() = __c.__map_.__alloc();
1308        }
1309
1310    _LIBCPP_HIDE_FROM_ABI
1311    void __copy_assign_alloc(const deque&, false_type)
1312        {}
1313
1314    _LIBCPP_HIDE_FROM_ABI void __move_assign(deque& __c, true_type)
1315        _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value);
1316    _LIBCPP_HIDE_FROM_ABI void __move_assign(deque& __c, false_type);
1317};
1318
1319template <class _Tp, class _Alloc>
1320_LIBCPP_CONSTEXPR const typename allocator_traits<_Alloc>::difference_type deque<_Tp, _Alloc>::__block_size =
1321    __deque_block_size<value_type, difference_type>::value;
1322
1323#if _LIBCPP_STD_VER >= 17
1324template<class _InputIterator,
1325         class _Alloc = allocator<__iter_value_type<_InputIterator>>,
1326         class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
1327         class = enable_if_t<__is_allocator<_Alloc>::value>
1328         >
1329deque(_InputIterator, _InputIterator)
1330  -> deque<__iter_value_type<_InputIterator>, _Alloc>;
1331
1332template<class _InputIterator,
1333         class _Alloc,
1334         class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
1335         class = enable_if_t<__is_allocator<_Alloc>::value>
1336         >
1337deque(_InputIterator, _InputIterator, _Alloc)
1338  -> deque<__iter_value_type<_InputIterator>, _Alloc>;
1339#endif
1340
1341#if _LIBCPP_STD_VER >= 23
1342template <ranges::input_range _Range,
1343          class _Alloc = allocator<ranges::range_value_t<_Range>>,
1344          class = enable_if_t<__is_allocator<_Alloc>::value>
1345          >
1346deque(from_range_t, _Range&&, _Alloc = _Alloc())
1347  -> deque<ranges::range_value_t<_Range>, _Alloc>;
1348#endif
1349
1350template <class _Tp, class _Allocator>
1351deque<_Tp, _Allocator>::deque(size_type __n)
1352    : __start_(0), __size_(0, __default_init_tag())
1353{
1354    __annotate_new(0);
1355    if (__n > 0)
1356        __append(__n);
1357}
1358
1359#if _LIBCPP_STD_VER >= 14
1360template <class _Tp, class _Allocator>
1361deque<_Tp, _Allocator>::deque(size_type __n, const _Allocator& __a)
1362    : __map_(__pointer_allocator(__a)), __start_(0), __size_(0, __a)
1363{
1364    __annotate_new(0);
1365    if (__n > 0)
1366        __append(__n);
1367}
1368#endif
1369
1370template <class _Tp, class _Allocator>
1371deque<_Tp, _Allocator>::deque(size_type __n, const value_type& __v)
1372    : __start_(0), __size_(0, __default_init_tag())
1373{
1374    __annotate_new(0);
1375    if (__n > 0)
1376        __append(__n, __v);
1377}
1378
1379template <class _Tp, class _Allocator>
1380template <class _InputIter>
1381deque<_Tp, _Allocator>::deque(_InputIter __f, _InputIter __l,
1382              typename enable_if<__has_input_iterator_category<_InputIter>::value>::type*)
1383    : __start_(0), __size_(0, __default_init_tag())
1384{
1385    __annotate_new(0);
1386    __append(__f, __l);
1387}
1388
1389template <class _Tp, class _Allocator>
1390template <class _InputIter>
1391deque<_Tp, _Allocator>::deque(_InputIter __f, _InputIter __l, const allocator_type& __a,
1392              typename enable_if<__has_input_iterator_category<_InputIter>::value>::type*)
1393    : __map_(__pointer_allocator(__a)), __start_(0), __size_(0, __a)
1394{
1395    __annotate_new(0);
1396    __append(__f, __l);
1397}
1398
1399template <class _Tp, class _Allocator>
1400deque<_Tp, _Allocator>::deque(const deque& __c)
1401    : __map_(__pointer_allocator(__alloc_traits::select_on_container_copy_construction(__c.__alloc()))),
1402      __start_(0),
1403      __size_(0, __map_.__alloc())
1404{
1405    __annotate_new(0);
1406    __append(__c.begin(), __c.end());
1407}
1408
1409template <class _Tp, class _Allocator>
1410deque<_Tp, _Allocator>::deque(const deque& __c, const __type_identity_t<allocator_type>& __a)
1411    : __map_(__pointer_allocator(__a)), __start_(0), __size_(0, __a)
1412{
1413    __annotate_new(0);
1414    __append(__c.begin(), __c.end());
1415}
1416
1417template <class _Tp, class _Allocator>
1418deque<_Tp, _Allocator>&
1419deque<_Tp, _Allocator>::operator=(const deque& __c)
1420{
1421    if (this != _VSTD::addressof(__c))
1422    {
1423        __copy_assign_alloc(__c);
1424        assign(__c.begin(), __c.end());
1425    }
1426    return *this;
1427}
1428
1429#ifndef _LIBCPP_CXX03_LANG
1430
1431template <class _Tp, class _Allocator>
1432deque<_Tp, _Allocator>::deque(initializer_list<value_type> __il)
1433    : __start_(0), __size_(0, __default_init_tag())
1434{
1435    __annotate_new(0);
1436    __append(__il.begin(), __il.end());
1437}
1438
1439template <class _Tp, class _Allocator>
1440deque<_Tp, _Allocator>::deque(initializer_list<value_type> __il, const allocator_type& __a)
1441    : __map_(__pointer_allocator(__a)), __start_(0), __size_(0, __a)
1442{
1443    __annotate_new(0);
1444    __append(__il.begin(), __il.end());
1445}
1446
1447template <class _Tp, class _Allocator>
1448inline
1449deque<_Tp, _Allocator>::deque(deque&& __c)
1450    _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
1451    : __map_(std::move(__c.__map_)), __start_(std::move(__c.__start_)), __size_(std::move(__c.__size_))
1452{
1453  __c.__start_ = 0;
1454  __c.__size() = 0;
1455}
1456
1457template <class _Tp, class _Allocator>
1458inline
1459deque<_Tp, _Allocator>::deque(deque&& __c, const __type_identity_t<allocator_type>& __a)
1460    : __map_(std::move(__c.__map_), __pointer_allocator(__a)),
1461      __start_(std::move(__c.__start_)),
1462      __size_(std::move(__c.__size()), __a)
1463{
1464    if (__a == __c.__alloc())
1465    {
1466        __c.__start_ = 0;
1467        __c.__size() = 0;
1468    }
1469    else
1470    {
1471        __map_.clear();
1472        __start_ = 0;
1473        __size() = 0;
1474        typedef move_iterator<iterator> _Ip;
1475        assign(_Ip(__c.begin()), _Ip(__c.end()));
1476    }
1477}
1478
1479template <class _Tp, class _Allocator>
1480inline
1481deque<_Tp, _Allocator>&
1482deque<_Tp, _Allocator>::operator=(deque&& __c)
1483        _NOEXCEPT_(__alloc_traits::propagate_on_container_move_assignment::value &&
1484                   is_nothrow_move_assignable<allocator_type>::value)
1485{
1486    __move_assign(__c, integral_constant<bool,
1487          __alloc_traits::propagate_on_container_move_assignment::value>());
1488    return *this;
1489}
1490
1491template <class _Tp, class _Allocator>
1492void
1493deque<_Tp, _Allocator>::__move_assign(deque& __c, false_type)
1494{
1495    if (__alloc() != __c.__alloc())
1496    {
1497        typedef move_iterator<iterator> _Ip;
1498        assign(_Ip(__c.begin()), _Ip(__c.end()));
1499    }
1500    else
1501        __move_assign(__c, true_type());
1502}
1503
1504template <class _Tp, class _Allocator>
1505void
1506deque<_Tp, _Allocator>::__move_assign(deque& __c, true_type)
1507    _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
1508{
1509    clear();
1510    shrink_to_fit();
1511    __move_assign(__c);
1512}
1513
1514#endif // _LIBCPP_CXX03_LANG
1515
1516template <class _Tp, class _Allocator>
1517template <class _InputIter>
1518void
1519deque<_Tp, _Allocator>::assign(_InputIter __f, _InputIter __l,
1520                               typename enable_if<__has_input_iterator_category<_InputIter>::value &&
1521                                                 !__has_random_access_iterator_category<_InputIter>::value>::type*)
1522{
1523  __assign_with_sentinel(__f, __l);
1524}
1525
1526template <class _Tp, class _Allocator>
1527template <class _Iterator, class _Sentinel>
1528_LIBCPP_HIDE_FROM_ABI
1529void deque<_Tp, _Allocator>::__assign_with_sentinel(_Iterator __f, _Sentinel __l) {
1530    iterator __i = begin();
1531    iterator __e = end();
1532    for (; __f != __l && __i != __e; ++__f, (void) ++__i)
1533        *__i = *__f;
1534    if (__f != __l)
1535        __append_with_sentinel(std::move(__f), std::move(__l));
1536    else
1537        __erase_to_end(__i);
1538}
1539
1540template <class _Tp, class _Allocator>
1541template <class _RAIter>
1542void
1543deque<_Tp, _Allocator>::assign(_RAIter __f, _RAIter __l,
1544                               typename enable_if<__has_random_access_iterator_category<_RAIter>::value>::type*)
1545{
1546  __assign_with_size_random_access(__f, __l - __f);
1547}
1548
1549template <class _Tp, class _Allocator>
1550template <class _RandomAccessIterator>
1551_LIBCPP_HIDE_FROM_ABI
1552void deque<_Tp, _Allocator>::__assign_with_size_random_access(_RandomAccessIterator __f, difference_type __n) {
1553    if (static_cast<size_type>(__n) > size())
1554    {
1555        auto __l = __f + size();
1556        std::copy(__f, __l, begin());
1557        __append_with_size(__l, __n - size());
1558    }
1559    else
1560        __erase_to_end(std::copy_n(__f, __n, begin()));
1561}
1562
1563template <class _Tp, class _Allocator>
1564template <class _Iterator>
1565_LIBCPP_HIDE_FROM_ABI
1566void deque<_Tp, _Allocator>::__assign_with_size(_Iterator __f, difference_type __n) {
1567  if (static_cast<size_type>(__n) > size()) {
1568    auto __added_size = __n - size();
1569
1570    auto __i = begin();
1571    for (auto __count = size(); __count != 0; --__count) {
1572      *__i++ = *__f++;
1573    }
1574
1575    __append_with_size(__f, __added_size);
1576
1577  } else {
1578    __erase_to_end(std::copy_n(__f, __n, begin()));
1579  }
1580}
1581
1582template <class _Tp, class _Allocator>
1583void
1584deque<_Tp, _Allocator>::assign(size_type __n, const value_type& __v)
1585{
1586    if (__n > size())
1587    {
1588        _VSTD::fill_n(begin(), size(), __v);
1589        __n -= size();
1590        __append(__n, __v);
1591    }
1592    else
1593        __erase_to_end(_VSTD::fill_n(begin(), __n, __v));
1594}
1595
1596template <class _Tp, class _Allocator>
1597inline
1598_Allocator
1599deque<_Tp, _Allocator>::get_allocator() const _NOEXCEPT
1600{
1601    return __alloc();
1602}
1603
1604template <class _Tp, class _Allocator>
1605void
1606deque<_Tp, _Allocator>::resize(size_type __n)
1607{
1608    if (__n > size())
1609        __append(__n - size());
1610    else if (__n < size())
1611        __erase_to_end(begin() + __n);
1612}
1613
1614template <class _Tp, class _Allocator>
1615void
1616deque<_Tp, _Allocator>::resize(size_type __n, const value_type& __v)
1617{
1618    if (__n > size())
1619        __append(__n - size(), __v);
1620    else if (__n < size())
1621        __erase_to_end(begin() + __n);
1622}
1623
1624template <class _Tp, class _Allocator>
1625void
1626deque<_Tp, _Allocator>::shrink_to_fit() _NOEXCEPT
1627{
1628    allocator_type& __a = __alloc();
1629    if (empty())
1630    {
1631        __annotate_delete();
1632        while (__map_.size() > 0)
1633        {
1634            __alloc_traits::deallocate(__a, __map_.back(), __block_size);
1635            __map_.pop_back();
1636        }
1637        __start_ = 0;
1638    }
1639    else
1640    {
1641      __maybe_remove_front_spare(/*__keep_one=*/false);
1642      __maybe_remove_back_spare(/*__keep_one=*/false);
1643    }
1644    __map_.shrink_to_fit();
1645}
1646
1647template <class _Tp, class _Allocator>
1648inline
1649typename deque<_Tp, _Allocator>::reference
1650deque<_Tp, _Allocator>::operator[](size_type __i) _NOEXCEPT
1651{
1652    size_type __p = __start_ + __i;
1653    return *(*(__map_.begin() + __p / __block_size) + __p % __block_size);
1654}
1655
1656template <class _Tp, class _Allocator>
1657inline
1658typename deque<_Tp, _Allocator>::const_reference
1659deque<_Tp, _Allocator>::operator[](size_type __i) const _NOEXCEPT
1660{
1661    size_type __p = __start_ + __i;
1662    return *(*(__map_.begin() + __p / __block_size) + __p % __block_size);
1663}
1664
1665template <class _Tp, class _Allocator>
1666inline
1667typename deque<_Tp, _Allocator>::reference
1668deque<_Tp, _Allocator>::at(size_type __i)
1669{
1670    if (__i >= size())
1671        _VSTD::__throw_out_of_range("deque");
1672    size_type __p = __start_ + __i;
1673    return *(*(__map_.begin() + __p / __block_size) + __p % __block_size);
1674}
1675
1676template <class _Tp, class _Allocator>
1677inline
1678typename deque<_Tp, _Allocator>::const_reference
1679deque<_Tp, _Allocator>::at(size_type __i) const
1680{
1681    if (__i >= size())
1682        _VSTD::__throw_out_of_range("deque");
1683    size_type __p = __start_ + __i;
1684    return *(*(__map_.begin() + __p / __block_size) + __p % __block_size);
1685}
1686
1687template <class _Tp, class _Allocator>
1688inline
1689typename deque<_Tp, _Allocator>::reference
1690deque<_Tp, _Allocator>::front() _NOEXCEPT
1691{
1692    return *(*(__map_.begin() + __start_ / __block_size)
1693                                    + __start_ % __block_size);
1694}
1695
1696template <class _Tp, class _Allocator>
1697inline
1698typename deque<_Tp, _Allocator>::const_reference
1699deque<_Tp, _Allocator>::front() const _NOEXCEPT
1700{
1701    return *(*(__map_.begin() + __start_ / __block_size)
1702                                      + __start_ % __block_size);
1703}
1704
1705template <class _Tp, class _Allocator>
1706inline
1707typename deque<_Tp, _Allocator>::reference
1708deque<_Tp, _Allocator>::back() _NOEXCEPT
1709{
1710    size_type __p = size() + __start_ - 1;
1711    return *(*(__map_.begin() + __p / __block_size) + __p % __block_size);
1712}
1713
1714template <class _Tp, class _Allocator>
1715inline
1716typename deque<_Tp, _Allocator>::const_reference
1717deque<_Tp, _Allocator>::back() const _NOEXCEPT
1718{
1719    size_type __p = size() + __start_ - 1;
1720    return *(*(__map_.begin() + __p / __block_size) + __p % __block_size);
1721}
1722
1723template <class _Tp, class _Allocator>
1724void
1725deque<_Tp, _Allocator>::push_back(const value_type& __v)
1726{
1727    allocator_type& __a = __alloc();
1728    if (__back_spare() == 0)
1729        __add_back_capacity();
1730    // __back_spare() >= 1
1731    __annotate_increase_back(1);
1732    __alloc_traits::construct(__a, _VSTD::addressof(*end()), __v);
1733    ++__size();
1734}
1735
1736template <class _Tp, class _Allocator>
1737void
1738deque<_Tp, _Allocator>::push_front(const value_type& __v)
1739{
1740    allocator_type& __a = __alloc();
1741    if (__front_spare() == 0)
1742        __add_front_capacity();
1743    // __front_spare() >= 1
1744    __annotate_increase_front(1);
1745    __alloc_traits::construct(__a, _VSTD::addressof(*--begin()), __v);
1746    --__start_;
1747    ++__size();
1748}
1749
1750#ifndef _LIBCPP_CXX03_LANG
1751template <class _Tp, class _Allocator>
1752void
1753deque<_Tp, _Allocator>::push_back(value_type&& __v)
1754{
1755    allocator_type& __a = __alloc();
1756    if (__back_spare() == 0)
1757        __add_back_capacity();
1758    // __back_spare() >= 1
1759    __annotate_increase_back(1);
1760    __alloc_traits::construct(__a, _VSTD::addressof(*end()), _VSTD::move(__v));
1761    ++__size();
1762}
1763
1764template <class _Tp, class _Allocator>
1765template <class... _Args>
1766#if _LIBCPP_STD_VER >= 17
1767typename deque<_Tp, _Allocator>::reference
1768#else
1769void
1770#endif
1771deque<_Tp, _Allocator>::emplace_back(_Args&&... __args)
1772{
1773    allocator_type& __a = __alloc();
1774    if (__back_spare() == 0)
1775        __add_back_capacity();
1776    // __back_spare() >= 1
1777    __annotate_increase_back(1);
1778    __alloc_traits::construct(__a, _VSTD::addressof(*end()),
1779                              _VSTD::forward<_Args>(__args)...);
1780    ++__size();
1781#if _LIBCPP_STD_VER >= 17
1782    return *--end();
1783#endif
1784}
1785
1786template <class _Tp, class _Allocator>
1787void
1788deque<_Tp, _Allocator>::push_front(value_type&& __v)
1789{
1790    allocator_type& __a = __alloc();
1791    if (__front_spare() == 0)
1792        __add_front_capacity();
1793    // __front_spare() >= 1
1794    __annotate_increase_front(1);
1795    __alloc_traits::construct(__a, _VSTD::addressof(*--begin()), _VSTD::move(__v));
1796    --__start_;
1797    ++__size();
1798}
1799
1800
1801template <class _Tp, class _Allocator>
1802template <class... _Args>
1803#if _LIBCPP_STD_VER >= 17
1804typename deque<_Tp, _Allocator>::reference
1805#else
1806void
1807#endif
1808deque<_Tp, _Allocator>::emplace_front(_Args&&... __args)
1809{
1810    allocator_type& __a = __alloc();
1811    if (__front_spare() == 0)
1812        __add_front_capacity();
1813    // __front_spare() >= 1
1814    __annotate_increase_front(1);
1815    __alloc_traits::construct(__a, _VSTD::addressof(*--begin()), _VSTD::forward<_Args>(__args)...);
1816    --__start_;
1817    ++__size();
1818#if _LIBCPP_STD_VER >= 17
1819    return *begin();
1820#endif
1821}
1822
1823template <class _Tp, class _Allocator>
1824typename deque<_Tp, _Allocator>::iterator
1825deque<_Tp, _Allocator>::insert(const_iterator __p, value_type&& __v)
1826{
1827    size_type __pos = __p - begin();
1828    size_type __to_end = size() - __pos;
1829    allocator_type& __a = __alloc();
1830    if (__pos < __to_end)
1831    {   // insert by shifting things backward
1832        if (__front_spare() == 0)
1833            __add_front_capacity();
1834        // __front_spare() >= 1
1835        __annotate_increase_front(1);
1836        if (__pos == 0)
1837        {
1838            __alloc_traits::construct(__a, _VSTD::addressof(*--begin()), _VSTD::move(__v));
1839            --__start_;
1840            ++__size();
1841        }
1842        else
1843        {
1844            iterator __b = begin();
1845            iterator __bm1 = _VSTD::prev(__b);
1846            __alloc_traits::construct(__a, _VSTD::addressof(*__bm1), _VSTD::move(*__b));
1847            --__start_;
1848            ++__size();
1849            if (__pos > 1)
1850                __b = _VSTD::move(_VSTD::next(__b), __b + __pos, __b);
1851            *__b = _VSTD::move(__v);
1852        }
1853    }
1854    else
1855    {   // insert by shifting things forward
1856        if (__back_spare() == 0)
1857            __add_back_capacity();
1858        // __back_capacity >= 1
1859        __annotate_increase_back(1);
1860        size_type __de = size() - __pos;
1861        if (__de == 0)
1862        {
1863            __alloc_traits::construct(__a, _VSTD::addressof(*end()), _VSTD::move(__v));
1864            ++__size();
1865        }
1866        else
1867        {
1868            iterator __e = end();
1869            iterator __em1 = _VSTD::prev(__e);
1870            __alloc_traits::construct(__a, _VSTD::addressof(*__e), _VSTD::move(*__em1));
1871            ++__size();
1872            if (__de > 1)
1873                __e = _VSTD::move_backward(__e - __de, __em1, __e);
1874            *--__e = _VSTD::move(__v);
1875        }
1876    }
1877    return begin() + __pos;
1878}
1879
1880template <class _Tp, class _Allocator>
1881template <class... _Args>
1882typename deque<_Tp, _Allocator>::iterator
1883deque<_Tp, _Allocator>::emplace(const_iterator __p, _Args&&... __args)
1884{
1885    size_type __pos = __p - begin();
1886    size_type __to_end = size() - __pos;
1887    allocator_type& __a = __alloc();
1888    if (__pos < __to_end)
1889    {   // insert by shifting things backward
1890        if (__front_spare() == 0)
1891            __add_front_capacity();
1892        // __front_spare() >= 1
1893        __annotate_increase_front(1);
1894        if (__pos == 0)
1895        {
1896            __alloc_traits::construct(__a, _VSTD::addressof(*--begin()), _VSTD::forward<_Args>(__args)...);
1897            --__start_;
1898            ++__size();
1899        }
1900        else
1901        {
1902            __temp_value<value_type, _Allocator> __tmp(__alloc(), _VSTD::forward<_Args>(__args)...);
1903            iterator __b = begin();
1904            iterator __bm1 = _VSTD::prev(__b);
1905            __alloc_traits::construct(__a, _VSTD::addressof(*__bm1), _VSTD::move(*__b));
1906            --__start_;
1907            ++__size();
1908            if (__pos > 1)
1909                __b = _VSTD::move(_VSTD::next(__b), __b + __pos, __b);
1910            *__b = _VSTD::move(__tmp.get());
1911        }
1912    }
1913    else
1914    {   // insert by shifting things forward
1915        if (__back_spare() == 0)
1916            __add_back_capacity();
1917        // __back_capacity >= 1
1918        __annotate_increase_back(1);
1919        size_type __de = size() - __pos;
1920        if (__de == 0)
1921        {
1922            __alloc_traits::construct(__a, _VSTD::addressof(*end()), _VSTD::forward<_Args>(__args)...);
1923            ++__size();
1924        }
1925        else
1926        {
1927            __temp_value<value_type, _Allocator> __tmp(__alloc(), _VSTD::forward<_Args>(__args)...);
1928            iterator __e = end();
1929            iterator __em1 = _VSTD::prev(__e);
1930            __alloc_traits::construct(__a, _VSTD::addressof(*__e), _VSTD::move(*__em1));
1931            ++__size();
1932            if (__de > 1)
1933                __e = _VSTD::move_backward(__e - __de, __em1, __e);
1934            *--__e = _VSTD::move(__tmp.get());
1935        }
1936    }
1937    return begin() + __pos;
1938}
1939
1940#endif // _LIBCPP_CXX03_LANG
1941
1942
1943template <class _Tp, class _Allocator>
1944typename deque<_Tp, _Allocator>::iterator
1945deque<_Tp, _Allocator>::insert(const_iterator __p, const value_type& __v)
1946{
1947    size_type __pos = __p - begin();
1948    size_type __to_end = size() - __pos;
1949    allocator_type& __a = __alloc();
1950    if (__pos < __to_end)
1951    {   // insert by shifting things backward
1952        if (__front_spare() == 0)
1953            __add_front_capacity();
1954        // __front_spare() >= 1
1955        __annotate_increase_front(1);
1956        if (__pos == 0)
1957        {
1958            __alloc_traits::construct(__a, _VSTD::addressof(*--begin()), __v);
1959            --__start_;
1960            ++__size();
1961        }
1962        else
1963        {
1964            const_pointer __vt = pointer_traits<const_pointer>::pointer_to(__v);
1965            iterator __b = begin();
1966            iterator __bm1 = _VSTD::prev(__b);
1967            if (__vt == pointer_traits<const_pointer>::pointer_to(*__b))
1968                __vt = pointer_traits<const_pointer>::pointer_to(*__bm1);
1969            __alloc_traits::construct(__a, _VSTD::addressof(*__bm1), _VSTD::move(*__b));
1970            --__start_;
1971            ++__size();
1972            if (__pos > 1)
1973                __b = __move_and_check(_VSTD::next(__b), __b + __pos, __b, __vt);
1974            *__b = *__vt;
1975        }
1976    }
1977    else
1978    {   // insert by shifting things forward
1979        if (__back_spare() == 0)
1980            __add_back_capacity();
1981        // __back_capacity >= 1
1982        __annotate_increase_back(1);
1983        size_type __de = size() - __pos;
1984        if (__de == 0)
1985        {
1986            __alloc_traits::construct(__a, _VSTD::addressof(*end()), __v);
1987            ++__size();
1988        }
1989        else
1990        {
1991            const_pointer __vt = pointer_traits<const_pointer>::pointer_to(__v);
1992            iterator __e = end();
1993            iterator __em1 = _VSTD::prev(__e);
1994            if (__vt == pointer_traits<const_pointer>::pointer_to(*__em1))
1995                __vt = pointer_traits<const_pointer>::pointer_to(*__e);
1996            __alloc_traits::construct(__a, _VSTD::addressof(*__e), _VSTD::move(*__em1));
1997            ++__size();
1998            if (__de > 1)
1999                __e = __move_backward_and_check(__e - __de, __em1, __e, __vt);
2000            *--__e = *__vt;
2001        }
2002    }
2003    return begin() + __pos;
2004}
2005
2006template <class _Tp, class _Allocator>
2007typename deque<_Tp, _Allocator>::iterator
2008deque<_Tp, _Allocator>::insert(const_iterator __p, size_type __n, const value_type& __v)
2009{
2010    size_type __pos = __p - begin();
2011    size_type __to_end = __size() - __pos;
2012    allocator_type& __a = __alloc();
2013    if (__pos < __to_end)
2014    {   // insert by shifting things backward
2015        if (__n > __front_spare())
2016            __add_front_capacity(__n - __front_spare());
2017        // __n <= __front_spare()
2018        __annotate_increase_front(__n);
2019        iterator __old_begin = begin();
2020        iterator __i = __old_begin;
2021        if (__n > __pos)
2022        {
2023            for (size_type __m = __n - __pos; __m; --__m, --__start_, ++__size())
2024                __alloc_traits::construct(__a, _VSTD::addressof(*--__i), __v);
2025            __n = __pos;
2026        }
2027        if (__n > 0)
2028        {
2029            const_pointer __vt = pointer_traits<const_pointer>::pointer_to(__v);
2030            iterator __obn = __old_begin + __n;
2031            __move_construct_backward_and_check(__old_begin, __obn, __i, __vt);
2032            if (__n < __pos)
2033                __old_begin = __move_and_check(__obn, __old_begin + __pos, __old_begin, __vt);
2034            _VSTD::fill_n(__old_begin, __n, *__vt);
2035        }
2036    }
2037    else
2038    {   // insert by shifting things forward
2039        size_type __back_capacity = __back_spare();
2040        if (__n > __back_capacity)
2041            __add_back_capacity(__n - __back_capacity);
2042        // __n <= __back_capacity
2043        __annotate_increase_back(__n);
2044        iterator __old_end = end();
2045        iterator __i = __old_end;
2046        size_type __de = size() - __pos;
2047        if (__n > __de)
2048        {
2049            for (size_type __m = __n - __de; __m; --__m, (void) ++__i, ++__size())
2050                __alloc_traits::construct(__a, _VSTD::addressof(*__i), __v);
2051            __n = __de;
2052        }
2053        if (__n > 0)
2054        {
2055            const_pointer __vt = pointer_traits<const_pointer>::pointer_to(__v);
2056            iterator __oen = __old_end - __n;
2057            __move_construct_and_check(__oen, __old_end, __i, __vt);
2058            if (__n < __de)
2059                __old_end = __move_backward_and_check(__old_end - __de, __oen, __old_end, __vt);
2060            _VSTD::fill_n(__old_end - __n, __n, *__vt);
2061        }
2062    }
2063    return begin() + __pos;
2064}
2065
2066template <class _Tp, class _Allocator>
2067template <class _InputIter>
2068typename deque<_Tp, _Allocator>::iterator
2069deque<_Tp, _Allocator>::insert(const_iterator __p, _InputIter __f, _InputIter __l,
2070                               typename enable_if<__has_exactly_input_iterator_category<_InputIter>::value>::type*)
2071{
2072  return __insert_with_sentinel(__p, __f, __l);
2073}
2074
2075template <class _Tp, class _Allocator>
2076template <class _Iterator, class _Sentinel>
2077_LIBCPP_HIDE_FROM_ABI
2078typename deque<_Tp, _Allocator>::iterator
2079deque<_Tp, _Allocator>::__insert_with_sentinel(const_iterator __p, _Iterator __f, _Sentinel __l) {
2080    __split_buffer<value_type, allocator_type&> __buf(__alloc());
2081    __buf.__construct_at_end_with_sentinel(std::move(__f), std::move(__l));
2082    typedef typename __split_buffer<value_type, allocator_type&>::iterator __bi;
2083    return insert(__p, move_iterator<__bi>(__buf.begin()), move_iterator<__bi>(__buf.end()));
2084}
2085
2086template <class _Tp, class _Allocator>
2087template <class _ForwardIterator>
2088typename deque<_Tp, _Allocator>::iterator
2089deque<_Tp, _Allocator>::insert(const_iterator __p, _ForwardIterator __f, _ForwardIterator __l,
2090                               typename enable_if<__has_exactly_forward_iterator_category<_ForwardIterator>::value>::type*)
2091{
2092  return __insert_with_size(__p, __f, std::distance(__f, __l));
2093}
2094
2095template <class _Tp, class _Allocator>
2096template <class _Iterator>
2097_LIBCPP_HIDE_FROM_ABI
2098typename deque<_Tp, _Allocator>::iterator
2099deque<_Tp, _Allocator>::__insert_with_size(const_iterator __p, _Iterator __f, size_type __n) {
2100    __split_buffer<value_type, allocator_type&> __buf(__n, 0, __alloc());
2101    __buf.__construct_at_end_with_size(__f, __n);
2102    typedef typename __split_buffer<value_type, allocator_type&>::iterator __fwd;
2103    return insert(__p, move_iterator<__fwd>(__buf.begin()), move_iterator<__fwd>(__buf.end()));
2104}
2105
2106template <class _Tp, class _Allocator>
2107template <class _BiIter>
2108typename deque<_Tp, _Allocator>::iterator
2109deque<_Tp, _Allocator>::insert(const_iterator __p, _BiIter __f, _BiIter __l,
2110                               typename enable_if<__has_bidirectional_iterator_category<_BiIter>::value>::type*)
2111{
2112  return __insert_bidirectional(__p, __f, __l, std::distance(__f, __l));
2113}
2114
2115template <class _Tp, class _Allocator>
2116template <class _BiIter, class _Sentinel>
2117_LIBCPP_HIDE_FROM_ABI
2118typename deque<_Tp, _Allocator>::iterator
2119deque<_Tp, _Allocator>::__insert_bidirectional(const_iterator __p, _BiIter __f, _Sentinel, size_type __n) {
2120  return __insert_bidirectional(__p, __f, std::next(__f, __n), __n);
2121}
2122
2123template <class _Tp, class _Allocator>
2124template <class _BiIter>
2125_LIBCPP_HIDE_FROM_ABI
2126typename deque<_Tp, _Allocator>::iterator
2127deque<_Tp, _Allocator>::__insert_bidirectional(const_iterator __p, _BiIter __f, _BiIter __l, size_type __n) {
2128    size_type __pos = __p - begin();
2129    size_type __to_end = size() - __pos;
2130    allocator_type& __a = __alloc();
2131    if (__pos < __to_end)
2132    {   // insert by shifting things backward
2133        if (__n > __front_spare())
2134            __add_front_capacity(__n - __front_spare());
2135        // __n <= __front_spare()
2136        __annotate_increase_front(__n);
2137        iterator __old_begin = begin();
2138        iterator __i = __old_begin;
2139        _BiIter __m = __f;
2140        if (__n > __pos)
2141        {
2142            __m = __pos < __n / 2 ? _VSTD::prev(__l, __pos) : _VSTD::next(__f, __n - __pos);
2143            for (_BiIter __j = __m; __j != __f; --__start_, ++__size())
2144                __alloc_traits::construct(__a, _VSTD::addressof(*--__i), *--__j);
2145            __n = __pos;
2146        }
2147        if (__n > 0)
2148        {
2149            iterator __obn = __old_begin + __n;
2150            for (iterator __j = __obn; __j != __old_begin;)
2151            {
2152                __alloc_traits::construct(__a, _VSTD::addressof(*--__i), _VSTD::move(*--__j));
2153                --__start_;
2154                ++__size();
2155            }
2156            if (__n < __pos)
2157                __old_begin = _VSTD::move(__obn, __old_begin + __pos, __old_begin);
2158            _VSTD::copy(__m, __l, __old_begin);
2159        }
2160    }
2161    else
2162    {   // insert by shifting things forward
2163        size_type __back_capacity = __back_spare();
2164        if (__n > __back_capacity)
2165            __add_back_capacity(__n - __back_capacity);
2166        // __n <= __back_capacity
2167        __annotate_increase_back(__n);
2168        iterator __old_end = end();
2169        iterator __i = __old_end;
2170        _BiIter __m = __l;
2171        size_type __de = size() - __pos;
2172        if (__n > __de)
2173        {
2174            __m = __de < __n / 2 ? _VSTD::next(__f, __de) : _VSTD::prev(__l, __n - __de);
2175            for (_BiIter __j = __m; __j != __l; ++__i, (void) ++__j, ++__size())
2176                __alloc_traits::construct(__a, _VSTD::addressof(*__i), *__j);
2177            __n = __de;
2178        }
2179        if (__n > 0)
2180        {
2181            iterator __oen = __old_end - __n;
2182            for (iterator __j = __oen; __j != __old_end; ++__i, (void) ++__j, ++__size())
2183                __alloc_traits::construct(__a, _VSTD::addressof(*__i), _VSTD::move(*__j));
2184            if (__n < __de)
2185                __old_end = _VSTD::move_backward(__old_end - __de, __oen, __old_end);
2186            _VSTD::copy_backward(__f, __m, __old_end);
2187        }
2188    }
2189    return begin() + __pos;
2190}
2191
2192template <class _Tp, class _Allocator>
2193template <class _InpIter>
2194void
2195deque<_Tp, _Allocator>::__append(_InpIter __f, _InpIter __l,
2196                                 typename enable_if<__has_exactly_input_iterator_category<_InpIter>::value>::type*)
2197{
2198  __append_with_sentinel(__f, __l);
2199}
2200
2201template <class _Tp, class _Allocator>
2202template <class _InputIterator, class _Sentinel>
2203_LIBCPP_HIDE_FROM_ABI
2204void deque<_Tp, _Allocator>::__append_with_sentinel(_InputIterator __f, _Sentinel __l) {
2205    for (; __f != __l; ++__f)
2206#ifdef _LIBCPP_CXX03_LANG
2207        push_back(*__f);
2208#else
2209        emplace_back(*__f);
2210#endif
2211}
2212
2213template <class _Tp, class _Allocator>
2214template <class _ForIter>
2215void
2216deque<_Tp, _Allocator>::__append(_ForIter __f, _ForIter __l,
2217                                 typename enable_if<__has_forward_iterator_category<_ForIter>::value>::type*)
2218{
2219    __append_with_size(__f, std::distance(__f, __l));
2220}
2221
2222template <class _Tp, class _Allocator>
2223template <class _InputIterator>
2224_LIBCPP_HIDE_FROM_ABI
2225void deque<_Tp, _Allocator>::__append_with_size(_InputIterator __f, size_type __n) {
2226    allocator_type& __a = __alloc();
2227    size_type __back_capacity = __back_spare();
2228    if (__n > __back_capacity)
2229        __add_back_capacity(__n - __back_capacity);
2230
2231    // __n <= __back_capacity
2232    __annotate_increase_back(__n);
2233    for (__deque_block_range __br : __deque_range(end(), end() + __n)) {
2234      _ConstructTransaction __tx(this, __br);
2235      for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_, (void)++__f) {
2236        __alloc_traits::construct(__a, _VSTD::__to_address(__tx.__pos_), *__f);
2237      }
2238    }
2239}
2240
2241template <class _Tp, class _Allocator>
2242void
2243deque<_Tp, _Allocator>::__append(size_type __n)
2244{
2245    allocator_type& __a = __alloc();
2246    size_type __back_capacity = __back_spare();
2247    if (__n > __back_capacity)
2248        __add_back_capacity(__n - __back_capacity);
2249    // __n <= __back_capacity
2250    __annotate_increase_back(__n);
2251    for (__deque_block_range __br : __deque_range(end(), end() + __n)) {
2252      _ConstructTransaction __tx(this, __br);
2253      for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_) {
2254        __alloc_traits::construct(__a, _VSTD::__to_address(__tx.__pos_));
2255      }
2256    }
2257}
2258
2259template <class _Tp, class _Allocator>
2260void
2261deque<_Tp, _Allocator>::__append(size_type __n, const value_type& __v)
2262{
2263    allocator_type& __a = __alloc();
2264    size_type __back_capacity = __back_spare();
2265    if (__n > __back_capacity)
2266        __add_back_capacity(__n - __back_capacity);
2267    // __n <= __back_capacity
2268    __annotate_increase_back(__n);
2269    for (__deque_block_range __br : __deque_range(end(), end() + __n)) {
2270      _ConstructTransaction __tx(this, __br);
2271      for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_) {
2272        __alloc_traits::construct(__a, _VSTD::__to_address(__tx.__pos_), __v);
2273      }
2274    }
2275
2276}
2277
2278// Create front capacity for one block of elements.
2279// Strong guarantee.  Either do it or don't touch anything.
2280template <class _Tp, class _Allocator>
2281void
2282deque<_Tp, _Allocator>::__add_front_capacity()
2283{
2284    allocator_type& __a = __alloc();
2285    if (__back_spare() >= __block_size)
2286    {
2287        __start_ += __block_size;
2288        pointer __pt = __map_.back();
2289        __map_.pop_back();
2290        __map_.push_front(__pt);
2291    }
2292    // Else if __map_.size() < __map_.capacity() then we need to allocate 1 buffer
2293    else if (__map_.size() < __map_.capacity())
2294    {   // we can put the new buffer into the map, but don't shift things around
2295        // until all buffers are allocated.  If we throw, we don't need to fix
2296        // anything up (any added buffers are undetectible)
2297        if (__map_.__front_spare() > 0)
2298            __map_.push_front(__alloc_traits::allocate(__a, __block_size));
2299        else
2300        {
2301            __map_.push_back(__alloc_traits::allocate(__a, __block_size));
2302            // Done allocating, reorder capacity
2303            pointer __pt = __map_.back();
2304            __map_.pop_back();
2305            __map_.push_front(__pt);
2306        }
2307        __start_ = __map_.size() == 1 ?
2308                               __block_size / 2 :
2309                               __start_ + __block_size;
2310    }
2311    // Else need to allocate 1 buffer, *and* we need to reallocate __map_.
2312    else
2313    {
2314        __split_buffer<pointer, __pointer_allocator&>
2315            __buf(std::max<size_type>(2 * __map_.capacity(), 1),
2316                  0, __map_.__alloc());
2317
2318        typedef __allocator_destructor<_Allocator> _Dp;
2319        unique_ptr<pointer, _Dp> __hold(
2320            __alloc_traits::allocate(__a, __block_size),
2321                _Dp(__a, __block_size));
2322        __buf.push_back(__hold.get());
2323        __hold.release();
2324
2325        for (__map_pointer __i = __map_.begin();
2326                __i != __map_.end(); ++__i)
2327            __buf.push_back(*__i);
2328        _VSTD::swap(__map_.__first_, __buf.__first_);
2329        _VSTD::swap(__map_.__begin_, __buf.__begin_);
2330        _VSTD::swap(__map_.__end_, __buf.__end_);
2331        _VSTD::swap(__map_.__end_cap(), __buf.__end_cap());
2332        __start_ = __map_.size() == 1 ?
2333                               __block_size / 2 :
2334                               __start_ + __block_size;
2335    }
2336    __annotate_whole_block(0, __asan_poison);
2337}
2338
2339// Create front capacity for __n elements.
2340// Strong guarantee.  Either do it or don't touch anything.
2341template <class _Tp, class _Allocator>
2342void
2343deque<_Tp, _Allocator>::__add_front_capacity(size_type __n)
2344{
2345    allocator_type& __a = __alloc();
2346    size_type __nb = __recommend_blocks(__n + __map_.empty());
2347    // Number of unused blocks at back:
2348    size_type __back_capacity = __back_spare() / __block_size;
2349    __back_capacity = _VSTD::min(__back_capacity, __nb);  // don't take more than you need
2350    __nb -= __back_capacity;  // number of blocks need to allocate
2351    // If __nb == 0, then we have sufficient capacity.
2352    if (__nb == 0)
2353    {
2354        __start_ += __block_size * __back_capacity;
2355        for (; __back_capacity > 0; --__back_capacity)
2356        {
2357            pointer __pt = __map_.back();
2358            __map_.pop_back();
2359            __map_.push_front(__pt);
2360        }
2361    }
2362    // Else if __nb <= __map_.capacity() - __map_.size() then we need to allocate __nb buffers
2363    else if (__nb <= __map_.capacity() - __map_.size())
2364    {   // we can put the new buffers into the map, but don't shift things around
2365        // until all buffers are allocated.  If we throw, we don't need to fix
2366        // anything up (any added buffers are undetectible)
2367        for (; __nb > 0; --__nb, __start_ += __block_size - (__map_.size() == 1))
2368        {
2369            if (__map_.__front_spare() == 0)
2370                break;
2371            __map_.push_front(__alloc_traits::allocate(__a, __block_size));
2372            __annotate_whole_block(0, __asan_poison);
2373        }
2374        for (; __nb > 0; --__nb, ++__back_capacity)
2375            __map_.push_back(__alloc_traits::allocate(__a, __block_size));
2376        // Done allocating, reorder capacity
2377        __start_ += __back_capacity * __block_size;
2378        for (; __back_capacity > 0; --__back_capacity)
2379        {
2380            pointer __pt = __map_.back();
2381            __map_.pop_back();
2382            __map_.push_front(__pt);
2383            __annotate_whole_block(0, __asan_poison);
2384        }
2385    }
2386    // Else need to allocate __nb buffers, *and* we need to reallocate __map_.
2387    else
2388    {
2389        size_type __ds = (__nb + __back_capacity) * __block_size - __map_.empty();
2390        __split_buffer<pointer, __pointer_allocator&>
2391            __buf(std::max<size_type>(2* __map_.capacity(),
2392                                      __nb + __map_.size()),
2393                  0, __map_.__alloc());
2394#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
2395        try
2396        {
2397#endif // _LIBCPP_HAS_NO_EXCEPTIONS
2398            for (; __nb > 0; --__nb) {
2399                __buf.push_back(__alloc_traits::allocate(__a, __block_size));
2400                // ASan: this is empty container, we have to poison whole block
2401                __annotate_poison_block(
2402                    std::__to_address(__buf.back()),
2403                    std::__to_address(__buf.back() + __block_size));
2404            }
2405#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
2406        }
2407        catch (...)
2408        {
2409            __annotate_delete();
2410            for (__map_pointer __i = __buf.begin();
2411                    __i != __buf.end(); ++__i)
2412                __alloc_traits::deallocate(__a, *__i, __block_size);
2413            throw;
2414        }
2415#endif // _LIBCPP_HAS_NO_EXCEPTIONS
2416        for (; __back_capacity > 0; --__back_capacity)
2417        {
2418            __buf.push_back(__map_.back());
2419            __map_.pop_back();
2420        }
2421        for (__map_pointer __i = __map_.begin();
2422                __i != __map_.end(); ++__i)
2423            __buf.push_back(*__i);
2424        _VSTD::swap(__map_.__first_, __buf.__first_);
2425        _VSTD::swap(__map_.__begin_, __buf.__begin_);
2426        _VSTD::swap(__map_.__end_, __buf.__end_);
2427        _VSTD::swap(__map_.__end_cap(), __buf.__end_cap());
2428        __start_ += __ds;
2429    }
2430}
2431
2432// Create back capacity for one block of elements.
2433// Strong guarantee.  Either do it or don't touch anything.
2434template <class _Tp, class _Allocator>
2435void
2436deque<_Tp, _Allocator>::__add_back_capacity()
2437{
2438    allocator_type& __a = __alloc();
2439    if (__front_spare() >= __block_size)
2440    {
2441        __start_ -= __block_size;
2442        pointer __pt = __map_.front();
2443        __map_.pop_front();
2444        __map_.push_back(__pt);
2445    }
2446    // Else if __nb <= __map_.capacity() - __map_.size() then we need to allocate __nb buffers
2447    else if (__map_.size() < __map_.capacity())
2448    {   // we can put the new buffer into the map, but don't shift things around
2449        // until it is allocated.  If we throw, we don't need to fix
2450        // anything up (any added buffers are undetectible)
2451        if (__map_.__back_spare() != 0)
2452            __map_.push_back(__alloc_traits::allocate(__a, __block_size));
2453        else
2454        {
2455            __map_.push_front(__alloc_traits::allocate(__a, __block_size));
2456            // Done allocating, reorder capacity
2457            pointer __pt = __map_.front();
2458            __map_.pop_front();
2459            __map_.push_back(__pt);
2460        }
2461        __annotate_whole_block(__map_.size() - 1, __asan_poison);
2462    }
2463    // Else need to allocate 1 buffer, *and* we need to reallocate __map_.
2464    else
2465    {
2466        __split_buffer<pointer, __pointer_allocator&>
2467            __buf(std::max<size_type>(2* __map_.capacity(), 1),
2468                  __map_.size(),
2469                  __map_.__alloc());
2470
2471        typedef __allocator_destructor<_Allocator> _Dp;
2472        unique_ptr<pointer, _Dp> __hold(
2473            __alloc_traits::allocate(__a, __block_size),
2474                _Dp(__a, __block_size));
2475        __buf.push_back(__hold.get());
2476        __hold.release();
2477
2478        for (__map_pointer __i = __map_.end();
2479                __i != __map_.begin();)
2480            __buf.push_front(*--__i);
2481        _VSTD::swap(__map_.__first_, __buf.__first_);
2482        _VSTD::swap(__map_.__begin_, __buf.__begin_);
2483        _VSTD::swap(__map_.__end_, __buf.__end_);
2484        _VSTD::swap(__map_.__end_cap(), __buf.__end_cap());
2485        __annotate_whole_block(__map_.size() - 1, __asan_poison);
2486    }
2487}
2488
2489// Create back capacity for __n elements.
2490// Strong guarantee.  Either do it or don't touch anything.
2491template <class _Tp, class _Allocator>
2492void
2493deque<_Tp, _Allocator>::__add_back_capacity(size_type __n)
2494{
2495    allocator_type& __a = __alloc();
2496    size_type __nb = __recommend_blocks(__n + __map_.empty());
2497    // Number of unused blocks at front:
2498    size_type __front_capacity = __front_spare() / __block_size;
2499    __front_capacity = _VSTD::min(__front_capacity, __nb);  // don't take more than you need
2500    __nb -= __front_capacity;  // number of blocks need to allocate
2501    // If __nb == 0, then we have sufficient capacity.
2502    if (__nb == 0)
2503    {
2504        __start_ -= __block_size * __front_capacity;
2505        for (; __front_capacity > 0; --__front_capacity)
2506        {
2507            pointer __pt = __map_.front();
2508            __map_.pop_front();
2509            __map_.push_back(__pt);
2510        }
2511    }
2512    // Else if __nb <= __map_.capacity() - __map_.size() then we need to allocate __nb buffers
2513    else if (__nb <= __map_.capacity() - __map_.size())
2514    {   // we can put the new buffers into the map, but don't shift things around
2515        // until all buffers are allocated.  If we throw, we don't need to fix
2516        // anything up (any added buffers are undetectible)
2517        for (; __nb > 0; --__nb)
2518        {
2519            if (__map_.__back_spare() == 0)
2520                break;
2521            __map_.push_back(__alloc_traits::allocate(__a, __block_size));
2522            __annotate_whole_block(__map_.size() - 1, __asan_poison);
2523        }
2524        for (; __nb > 0; --__nb, ++__front_capacity, __start_ +=
2525                                 __block_size - (__map_.size() == 1)) {
2526            __map_.push_front(__alloc_traits::allocate(__a, __block_size));
2527            __annotate_whole_block(0, __asan_poison);
2528        }
2529        // Done allocating, reorder capacity
2530        __start_ -= __block_size * __front_capacity;
2531        for (; __front_capacity > 0; --__front_capacity)
2532        {
2533            pointer __pt = __map_.front();
2534            __map_.pop_front();
2535            __map_.push_back(__pt);
2536        }
2537    }
2538    // Else need to allocate __nb buffers, *and* we need to reallocate __map_.
2539    else
2540    {
2541        size_type __ds = __front_capacity * __block_size;
2542        __split_buffer<pointer, __pointer_allocator&>
2543            __buf(std::max<size_type>(2* __map_.capacity(),
2544                                      __nb + __map_.size()),
2545                  __map_.size() - __front_capacity,
2546                  __map_.__alloc());
2547#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
2548        try
2549        {
2550#endif // _LIBCPP_HAS_NO_EXCEPTIONS
2551            for (; __nb > 0; --__nb) {
2552                __buf.push_back(__alloc_traits::allocate(__a, __block_size));
2553                // ASan: this is an empty container, we have to poison the whole block
2554                __annotate_poison_block(
2555                    std::__to_address(__buf.back()),
2556                    std::__to_address(__buf.back() + __block_size));
2557            }
2558#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
2559        }
2560        catch (...)
2561        {
2562            __annotate_delete();
2563            for (__map_pointer __i = __buf.begin();
2564                    __i != __buf.end(); ++__i)
2565                __alloc_traits::deallocate(__a, *__i, __block_size);
2566            throw;
2567        }
2568#endif // _LIBCPP_HAS_NO_EXCEPTIONS
2569        for (; __front_capacity > 0; --__front_capacity)
2570        {
2571            __buf.push_back(__map_.front());
2572            __map_.pop_front();
2573        }
2574        for (__map_pointer __i = __map_.end();
2575                __i != __map_.begin();)
2576            __buf.push_front(*--__i);
2577        _VSTD::swap(__map_.__first_, __buf.__first_);
2578        _VSTD::swap(__map_.__begin_, __buf.__begin_);
2579        _VSTD::swap(__map_.__end_, __buf.__end_);
2580        _VSTD::swap(__map_.__end_cap(), __buf.__end_cap());
2581        __start_ -= __ds;
2582    }
2583}
2584
2585template <class _Tp, class _Allocator>
2586void
2587deque<_Tp, _Allocator>::pop_front()
2588{
2589    size_type __old_sz    = size();
2590    size_type __old_start = __start_;
2591    allocator_type& __a = __alloc();
2592    __alloc_traits::destroy(__a, _VSTD::__to_address(*(__map_.begin() +
2593                                                    __start_ / __block_size) +
2594                                                    __start_ % __block_size));
2595    --__size();
2596    ++__start_;
2597    __annotate_shrink_front(__old_sz, __old_start);
2598    __maybe_remove_front_spare();
2599}
2600
2601template <class _Tp, class _Allocator>
2602void
2603deque<_Tp, _Allocator>::pop_back()
2604{
2605    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "deque::pop_back called on an empty deque");
2606    size_type __old_sz    = size();
2607    size_type __old_start = __start_;
2608    allocator_type& __a = __alloc();
2609    size_type __p = size() + __start_ - 1;
2610    __alloc_traits::destroy(__a, _VSTD::__to_address(*(__map_.begin() +
2611                                                    __p / __block_size) +
2612                                                    __p % __block_size));
2613    --__size();
2614    __annotate_shrink_back(__old_sz, __old_start);
2615    __maybe_remove_back_spare();
2616}
2617
2618// move assign [__f, __l) to [__r, __r + (__l-__f)).
2619// If __vt points into [__f, __l), then subtract (__f - __r) from __vt.
2620template <class _Tp, class _Allocator>
2621typename deque<_Tp, _Allocator>::iterator
2622deque<_Tp, _Allocator>::__move_and_check(iterator __f, iterator __l, iterator __r,
2623                                         const_pointer& __vt)
2624{
2625    // as if
2626    //   for (; __f != __l; ++__f, ++__r)
2627    //       *__r = _VSTD::move(*__f);
2628    difference_type __n = __l - __f;
2629    while (__n > 0)
2630    {
2631        pointer __fb = __f.__ptr_;
2632        pointer __fe = *__f.__m_iter_ + __block_size;
2633        difference_type __bs = __fe - __fb;
2634        if (__bs > __n)
2635        {
2636            __bs = __n;
2637            __fe = __fb + __bs;
2638        }
2639        if (__fb <= __vt && __vt < __fe)
2640            __vt = (const_iterator(static_cast<__map_const_pointer>(__f.__m_iter_), __vt) -= __f - __r).__ptr_;
2641        __r = _VSTD::move(__fb, __fe, __r);
2642        __n -= __bs;
2643        __f += __bs;
2644    }
2645    return __r;
2646}
2647
2648// move assign [__f, __l) to [__r - (__l-__f), __r) backwards.
2649// If __vt points into [__f, __l), then add (__r - __l) to __vt.
2650template <class _Tp, class _Allocator>
2651typename deque<_Tp, _Allocator>::iterator
2652deque<_Tp, _Allocator>::__move_backward_and_check(iterator __f, iterator __l, iterator __r,
2653                                                  const_pointer& __vt)
2654{
2655    // as if
2656    //   while (__f != __l)
2657    //       *--__r = _VSTD::move(*--__l);
2658    difference_type __n = __l - __f;
2659    while (__n > 0)
2660    {
2661        --__l;
2662        pointer __lb = *__l.__m_iter_;
2663        pointer __le = __l.__ptr_ + 1;
2664        difference_type __bs = __le - __lb;
2665        if (__bs > __n)
2666        {
2667            __bs = __n;
2668            __lb = __le - __bs;
2669        }
2670        if (__lb <= __vt && __vt < __le)
2671            __vt = (const_iterator(static_cast<__map_const_pointer>(__l.__m_iter_), __vt) += __r - __l - 1).__ptr_;
2672        __r = _VSTD::move_backward(__lb, __le, __r);
2673        __n -= __bs;
2674        __l -= __bs - 1;
2675    }
2676    return __r;
2677}
2678
2679// move construct [__f, __l) to [__r, __r + (__l-__f)).
2680// If __vt points into [__f, __l), then add (__r - __f) to __vt.
2681template <class _Tp, class _Allocator>
2682void
2683deque<_Tp, _Allocator>::__move_construct_and_check(iterator __f, iterator __l,
2684                                                   iterator __r, const_pointer& __vt)
2685{
2686    allocator_type& __a = __alloc();
2687    // as if
2688    //   for (; __f != __l; ++__r, ++__f, ++__size())
2689    //       __alloc_traits::construct(__a, _VSTD::addressof(*__r), _VSTD::move(*__f));
2690    difference_type __n = __l - __f;
2691    while (__n > 0)
2692    {
2693        pointer __fb = __f.__ptr_;
2694        pointer __fe = *__f.__m_iter_ + __block_size;
2695        difference_type __bs = __fe - __fb;
2696        if (__bs > __n)
2697        {
2698            __bs = __n;
2699            __fe = __fb + __bs;
2700        }
2701        if (__fb <= __vt && __vt < __fe)
2702            __vt = (const_iterator(static_cast<__map_const_pointer>(__f.__m_iter_), __vt) += __r - __f).__ptr_;
2703        for (; __fb != __fe; ++__fb, ++__r, ++__size())
2704            __alloc_traits::construct(__a, _VSTD::addressof(*__r), _VSTD::move(*__fb));
2705        __n -= __bs;
2706        __f += __bs;
2707    }
2708}
2709
2710// move construct [__f, __l) to [__r - (__l-__f), __r) backwards.
2711// If __vt points into [__f, __l), then subtract (__l - __r) from __vt.
2712template <class _Tp, class _Allocator>
2713void
2714deque<_Tp, _Allocator>::__move_construct_backward_and_check(iterator __f, iterator __l,
2715                                                            iterator __r, const_pointer& __vt)
2716{
2717    allocator_type& __a = __alloc();
2718    // as if
2719    //   for (iterator __j = __l; __j != __f;)
2720    //   {
2721    //       __alloc_traitsconstruct(__a, _VSTD::addressof(*--__r), _VSTD::move(*--__j));
2722    //       --__start_;
2723    //       ++__size();
2724    //   }
2725    difference_type __n = __l - __f;
2726    while (__n > 0)
2727    {
2728        --__l;
2729        pointer __lb = *__l.__m_iter_;
2730        pointer __le = __l.__ptr_ + 1;
2731        difference_type __bs = __le - __lb;
2732        if (__bs > __n)
2733        {
2734            __bs = __n;
2735            __lb = __le - __bs;
2736        }
2737        if (__lb <= __vt && __vt < __le)
2738            __vt = (const_iterator(static_cast<__map_const_pointer>(__l.__m_iter_), __vt) -= __l - __r + 1).__ptr_;
2739        while (__le != __lb)
2740        {
2741            __alloc_traits::construct(__a, _VSTD::addressof(*--__r), _VSTD::move(*--__le));
2742            --__start_;
2743            ++__size();
2744        }
2745        __n -= __bs;
2746        __l -= __bs - 1;
2747    }
2748}
2749
2750template <class _Tp, class _Allocator>
2751typename deque<_Tp, _Allocator>::iterator
2752deque<_Tp, _Allocator>::erase(const_iterator __f)
2753{
2754    size_type __old_sz    = size();
2755    size_type __old_start = __start_;
2756    iterator __b = begin();
2757    difference_type __pos = __f - __b;
2758    iterator __p = __b + __pos;
2759    allocator_type& __a = __alloc();
2760    if (static_cast<size_t>(__pos) <= (size() - 1) / 2)
2761    {   // erase from front
2762        _VSTD::move_backward(__b, __p, _VSTD::next(__p));
2763        __alloc_traits::destroy(__a, _VSTD::addressof(*__b));
2764        --__size();
2765        ++__start_;
2766        __annotate_shrink_front(__old_sz, __old_start);
2767        __maybe_remove_front_spare();
2768    }
2769    else
2770    {   // erase from back
2771        iterator __i = _VSTD::move(_VSTD::next(__p), end(), __p);
2772        __alloc_traits::destroy(__a, _VSTD::addressof(*__i));
2773        --__size();
2774        __annotate_shrink_back(__old_sz, __old_start);
2775        __maybe_remove_back_spare();
2776    }
2777    return begin() + __pos;
2778}
2779
2780template <class _Tp, class _Allocator>
2781typename deque<_Tp, _Allocator>::iterator
2782deque<_Tp, _Allocator>::erase(const_iterator __f, const_iterator __l)
2783{
2784    size_type __old_sz    = size();
2785    size_type __old_start = __start_;
2786    difference_type __n = __l - __f;
2787    iterator __b = begin();
2788    difference_type __pos = __f - __b;
2789    iterator __p = __b + __pos;
2790    if (__n > 0)
2791    {
2792        allocator_type& __a = __alloc();
2793        if (static_cast<size_t>(__pos) <= (size() - __n) / 2)
2794        {   // erase from front
2795            iterator __i = _VSTD::move_backward(__b, __p, __p + __n);
2796            for (; __b != __i; ++__b)
2797                __alloc_traits::destroy(__a, _VSTD::addressof(*__b));
2798            __size() -= __n;
2799            __start_ += __n;
2800            __annotate_shrink_front(__old_sz, __old_start);
2801            while (__maybe_remove_front_spare()) {
2802            }
2803        }
2804        else
2805        {   // erase from back
2806            iterator __i = _VSTD::move(__p + __n, end(), __p);
2807            for (iterator __e = end(); __i != __e; ++__i)
2808                __alloc_traits::destroy(__a, _VSTD::addressof(*__i));
2809            __size() -= __n;
2810            __annotate_shrink_back(__old_sz, __old_start);
2811            while (__maybe_remove_back_spare()) {
2812            }
2813        }
2814    }
2815    return begin() + __pos;
2816}
2817
2818template <class _Tp, class _Allocator>
2819void
2820deque<_Tp, _Allocator>::__erase_to_end(const_iterator __f)
2821{
2822    size_type __old_sz    = size();
2823    size_type __old_start = __start_;
2824    iterator __e = end();
2825    difference_type __n = __e - __f;
2826    if (__n > 0)
2827    {
2828        allocator_type& __a = __alloc();
2829        iterator __b = begin();
2830        difference_type __pos = __f - __b;
2831        for (iterator __p = __b + __pos; __p != __e; ++__p)
2832            __alloc_traits::destroy(__a, _VSTD::addressof(*__p));
2833        __size() -= __n;
2834        __annotate_shrink_back(__old_sz, __old_start);
2835        while (__maybe_remove_back_spare()) {
2836        }
2837    }
2838}
2839
2840template <class _Tp, class _Allocator>
2841inline
2842void
2843deque<_Tp, _Allocator>::swap(deque& __c)
2844#if _LIBCPP_STD_VER >= 14
2845        _NOEXCEPT
2846#else
2847        _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value ||
2848                    __is_nothrow_swappable<allocator_type>::value)
2849#endif
2850{
2851    __map_.swap(__c.__map_);
2852    _VSTD::swap(__start_, __c.__start_);
2853    _VSTD::swap(__size(), __c.__size());
2854    _VSTD::__swap_allocator(__alloc(), __c.__alloc());
2855}
2856
2857template <class _Tp, class _Allocator>
2858inline
2859void
2860deque<_Tp, _Allocator>::clear() _NOEXCEPT
2861{
2862    __annotate_delete();
2863    allocator_type& __a = __alloc();
2864    for (iterator __i = begin(), __e = end(); __i != __e; ++__i)
2865        __alloc_traits::destroy(__a, _VSTD::addressof(*__i));
2866    __size() = 0;
2867    while (__map_.size() > 2)
2868    {
2869        __alloc_traits::deallocate(__a, __map_.front(), __block_size);
2870        __map_.pop_front();
2871    }
2872    switch (__map_.size())
2873    {
2874    case 1:
2875        __start_ = __block_size / 2;
2876        break;
2877    case 2:
2878        __start_ = __block_size;
2879        break;
2880    }
2881    __annotate_new(0);
2882}
2883
2884template <class _Tp, class _Allocator>
2885inline _LIBCPP_HIDE_FROM_ABI
2886bool
2887operator==(const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y)
2888{
2889    const typename deque<_Tp, _Allocator>::size_type __sz = __x.size();
2890    return __sz == __y.size() && _VSTD::equal(__x.begin(), __x.end(), __y.begin());
2891}
2892
2893#if _LIBCPP_STD_VER <= 17
2894
2895template <class _Tp, class _Allocator>
2896inline _LIBCPP_HIDE_FROM_ABI
2897bool
2898operator!=(const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y)
2899{
2900    return !(__x == __y);
2901}
2902
2903template <class _Tp, class _Allocator>
2904inline _LIBCPP_HIDE_FROM_ABI
2905bool
2906operator< (const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y)
2907{
2908    return _VSTD::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
2909}
2910
2911template <class _Tp, class _Allocator>
2912inline _LIBCPP_HIDE_FROM_ABI
2913bool
2914operator> (const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y)
2915{
2916    return __y < __x;
2917}
2918
2919template <class _Tp, class _Allocator>
2920inline _LIBCPP_HIDE_FROM_ABI
2921bool
2922operator>=(const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y)
2923{
2924    return !(__x < __y);
2925}
2926
2927template <class _Tp, class _Allocator>
2928inline _LIBCPP_HIDE_FROM_ABI
2929bool
2930operator<=(const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y)
2931{
2932    return !(__y < __x);
2933}
2934
2935#else // _LIBCPP_STD_VER <= 17
2936
2937template <class _Tp, class _Allocator>
2938_LIBCPP_HIDE_FROM_ABI __synth_three_way_result<_Tp>
2939operator<=>(const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y) {
2940    return std::lexicographical_compare_three_way(
2941        __x.begin(), __x.end(), __y.begin(), __y.end(), std::__synth_three_way<_Tp, _Tp>);
2942}
2943
2944#endif // _LIBCPP_STD_VER <= 17
2945
2946template <class _Tp, class _Allocator>
2947inline _LIBCPP_HIDE_FROM_ABI
2948void
2949swap(deque<_Tp, _Allocator>& __x, deque<_Tp, _Allocator>& __y)
2950    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
2951{
2952    __x.swap(__y);
2953}
2954
2955#if _LIBCPP_STD_VER >= 20
2956template <class _Tp, class _Allocator, class _Up>
2957inline _LIBCPP_HIDE_FROM_ABI typename deque<_Tp, _Allocator>::size_type
2958erase(deque<_Tp, _Allocator>& __c, const _Up& __v) {
2959  auto __old_size = __c.size();
2960  __c.erase(_VSTD::remove(__c.begin(), __c.end(), __v), __c.end());
2961  return __old_size - __c.size();
2962}
2963
2964template <class _Tp, class _Allocator, class _Predicate>
2965inline _LIBCPP_HIDE_FROM_ABI typename deque<_Tp, _Allocator>::size_type
2966erase_if(deque<_Tp, _Allocator>& __c, _Predicate __pred) {
2967  auto __old_size = __c.size();
2968  __c.erase(_VSTD::remove_if(__c.begin(), __c.end(), __pred), __c.end());
2969  return __old_size - __c.size();
2970}
2971
2972template <>
2973inline constexpr bool __format::__enable_insertable<std::deque<char>> = true;
2974#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
2975template <>
2976inline constexpr bool __format::__enable_insertable<std::deque<wchar_t>> = true;
2977#endif
2978
2979#endif // _LIBCPP_STD_VER >= 20
2980
2981_LIBCPP_END_NAMESPACE_STD
2982
2983#if _LIBCPP_STD_VER >= 17
2984_LIBCPP_BEGIN_NAMESPACE_STD
2985namespace pmr {
2986template <class _ValueT>
2987using deque _LIBCPP_AVAILABILITY_PMR = std::deque<_ValueT, polymorphic_allocator<_ValueT>>;
2988} // namespace pmr
2989_LIBCPP_END_NAMESPACE_STD
2990#endif
2991
2992_LIBCPP_POP_MACROS
2993
2994#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
2995#  include <algorithm>
2996#  include <atomic>
2997#  include <concepts>
2998#  include <cstdlib>
2999#  include <functional>
3000#  include <iosfwd>
3001#  include <iterator>
3002#  include <type_traits>
3003#  include <typeinfo>
3004#endif
3005
3006#endif // _LIBCPP_DEQUE
3007