• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4//                     The LLVM Compiler Infrastructure
5//
6// This file is dual licensed under the MIT and the University of Illinois Open
7// Source Licenses. See LICENSE.TXT for details.
8//
9//===----------------------------------------------------------------------===//
10
11#ifndef _LIBCPP__HASH_TABLE
12#define _LIBCPP__HASH_TABLE
13
14#include <__config>
15#include <initializer_list>
16#include <memory>
17#include <iterator>
18#include <algorithm>
19#include <cmath>
20
21#include <__undef_min_max>
22
23#ifdef _LIBCPP_DEBUG
24#   include <__debug>
25#else
26#   define _LIBCPP_ASSERT(x, m) ((void)0)
27#endif
28
29#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
30#pragma GCC system_header
31#endif
32
33_LIBCPP_BEGIN_NAMESPACE_STD
34
35_LIBCPP_FUNC_VIS
36size_t __next_prime(size_t __n);
37
38template <class _NodePtr>
39struct __hash_node_base
40{
41    typedef __hash_node_base __first_node;
42
43    _NodePtr    __next_;
44
45    _LIBCPP_INLINE_VISIBILITY __hash_node_base() _NOEXCEPT : __next_(nullptr) {}
46};
47
48template <class _Tp, class _VoidPtr>
49struct __hash_node
50    : public __hash_node_base
51             <
52                 typename pointer_traits<_VoidPtr>::template
53#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
54                     rebind<__hash_node<_Tp, _VoidPtr> >
55#else
56                     rebind<__hash_node<_Tp, _VoidPtr> >::other
57#endif
58             >
59{
60    typedef _Tp value_type;
61
62    size_t     __hash_;
63    value_type __value_;
64};
65
66inline _LIBCPP_INLINE_VISIBILITY
67bool
68__is_power2(size_t __bc)
69{
70    return __bc > 2 && !(__bc & (__bc - 1));
71}
72
73inline _LIBCPP_INLINE_VISIBILITY
74size_t
75__constrain_hash(size_t __h, size_t __bc)
76{
77    return !(__bc & (__bc - 1)) ? __h & (__bc - 1) : __h % __bc;
78}
79
80inline _LIBCPP_INLINE_VISIBILITY
81size_t
82__next_pow2(size_t __n)
83{
84    return size_t(1) << (std::numeric_limits<size_t>::digits - __clz(__n-1));
85}
86
87template <class _Tp, class _Hash, class _Equal, class _Alloc> class __hash_table;
88template <class _ConstNodePtr> class _LIBCPP_TYPE_VIS_ONLY __hash_const_iterator;
89template <class _HashIterator> class _LIBCPP_TYPE_VIS_ONLY __hash_map_iterator;
90template <class _HashIterator> class _LIBCPP_TYPE_VIS_ONLY __hash_map_const_iterator;
91template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
92    class _LIBCPP_TYPE_VIS_ONLY unordered_map;
93
94template <class _NodePtr>
95class _LIBCPP_TYPE_VIS_ONLY __hash_iterator
96{
97    typedef _NodePtr __node_pointer;
98
99    __node_pointer            __node_;
100
101public:
102    typedef forward_iterator_tag                         iterator_category;
103    typedef typename pointer_traits<__node_pointer>::element_type::value_type value_type;
104    typedef typename pointer_traits<__node_pointer>::difference_type difference_type;
105    typedef value_type&                                  reference;
106    typedef typename pointer_traits<__node_pointer>::template
107#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
108                     rebind<value_type>
109#else
110                     rebind<value_type>::other
111#endif
112                                                         pointer;
113
114    _LIBCPP_INLINE_VISIBILITY __hash_iterator() _NOEXCEPT
115#if _LIBCPP_STD_VER > 11
116    : __node_(nullptr)
117#endif
118    {
119#if _LIBCPP_DEBUG_LEVEL >= 2
120        __get_db()->__insert_i(this);
121#endif
122    }
123
124#if _LIBCPP_DEBUG_LEVEL >= 2
125
126    _LIBCPP_INLINE_VISIBILITY
127    __hash_iterator(const __hash_iterator& __i)
128        : __node_(__i.__node_)
129    {
130        __get_db()->__iterator_copy(this, &__i);
131    }
132
133    _LIBCPP_INLINE_VISIBILITY
134    ~__hash_iterator()
135    {
136        __get_db()->__erase_i(this);
137    }
138
139    _LIBCPP_INLINE_VISIBILITY
140    __hash_iterator& operator=(const __hash_iterator& __i)
141    {
142        if (this != &__i)
143        {
144            __get_db()->__iterator_copy(this, &__i);
145            __node_ = __i.__node_;
146        }
147        return *this;
148    }
149
150#endif  // _LIBCPP_DEBUG_LEVEL >= 2
151
152    _LIBCPP_INLINE_VISIBILITY
153        reference operator*() const
154        {
155#if _LIBCPP_DEBUG_LEVEL >= 2
156            _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
157                           "Attempted to dereference a non-dereferenceable unordered container iterator");
158#endif
159            return __node_->__value_;
160        }
161    _LIBCPP_INLINE_VISIBILITY
162        pointer operator->() const
163        {
164#if _LIBCPP_DEBUG_LEVEL >= 2
165            _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
166                           "Attempted to dereference a non-dereferenceable unordered container iterator");
167#endif
168            return pointer_traits<pointer>::pointer_to(__node_->__value_);
169        }
170
171    _LIBCPP_INLINE_VISIBILITY
172    __hash_iterator& operator++()
173    {
174#if _LIBCPP_DEBUG_LEVEL >= 2
175        _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
176                       "Attempted to increment non-incrementable unordered container iterator");
177#endif
178        __node_ = __node_->__next_;
179        return *this;
180    }
181
182    _LIBCPP_INLINE_VISIBILITY
183    __hash_iterator operator++(int)
184    {
185        __hash_iterator __t(*this);
186        ++(*this);
187        return __t;
188    }
189
190    friend _LIBCPP_INLINE_VISIBILITY
191    bool operator==(const __hash_iterator& __x, const __hash_iterator& __y)
192    {
193        return __x.__node_ == __y.__node_;
194    }
195    friend _LIBCPP_INLINE_VISIBILITY
196    bool operator!=(const __hash_iterator& __x, const __hash_iterator& __y)
197        {return !(__x == __y);}
198
199private:
200#if _LIBCPP_DEBUG_LEVEL >= 2
201    _LIBCPP_INLINE_VISIBILITY
202    __hash_iterator(__node_pointer __node, const void* __c) _NOEXCEPT
203        : __node_(__node)
204        {
205            __get_db()->__insert_ic(this, __c);
206        }
207#else
208    _LIBCPP_INLINE_VISIBILITY
209    __hash_iterator(__node_pointer __node) _NOEXCEPT
210        : __node_(__node)
211        {}
212#endif
213
214    template <class, class, class, class> friend class __hash_table;
215    template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_const_iterator;
216    template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_map_iterator;
217    template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_map;
218    template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_multimap;
219};
220
221template <class _ConstNodePtr>
222class _LIBCPP_TYPE_VIS_ONLY __hash_const_iterator
223{
224    typedef _ConstNodePtr __node_pointer;
225
226    __node_pointer         __node_;
227
228    typedef typename remove_const<
229        typename pointer_traits<__node_pointer>::element_type
230                                 >::type __node;
231
232public:
233    typedef forward_iterator_tag                       iterator_category;
234    typedef typename __node::value_type                value_type;
235    typedef typename pointer_traits<__node_pointer>::difference_type difference_type;
236    typedef const value_type&                          reference;
237    typedef typename pointer_traits<__node_pointer>::template
238#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
239            rebind<const value_type>
240#else
241            rebind<const value_type>::other
242#endif
243                                                       pointer;
244    typedef typename pointer_traits<__node_pointer>::template
245#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
246            rebind<__node>
247#else
248            rebind<__node>::other
249#endif
250                                                      __non_const_node_pointer;
251    typedef __hash_iterator<__non_const_node_pointer> __non_const_iterator;
252
253    _LIBCPP_INLINE_VISIBILITY __hash_const_iterator() _NOEXCEPT
254#if _LIBCPP_STD_VER > 11
255    : __node_(nullptr)
256#endif
257    {
258#if _LIBCPP_DEBUG_LEVEL >= 2
259        __get_db()->__insert_i(this);
260#endif
261    }
262    _LIBCPP_INLINE_VISIBILITY
263    __hash_const_iterator(const __non_const_iterator& __x) _NOEXCEPT
264        : __node_(__x.__node_)
265    {
266#if _LIBCPP_DEBUG_LEVEL >= 2
267        __get_db()->__iterator_copy(this, &__x);
268#endif
269    }
270
271#if _LIBCPP_DEBUG_LEVEL >= 2
272
273    _LIBCPP_INLINE_VISIBILITY
274    __hash_const_iterator(const __hash_const_iterator& __i)
275        : __node_(__i.__node_)
276    {
277        __get_db()->__iterator_copy(this, &__i);
278    }
279
280    _LIBCPP_INLINE_VISIBILITY
281    ~__hash_const_iterator()
282    {
283        __get_db()->__erase_i(this);
284    }
285
286    _LIBCPP_INLINE_VISIBILITY
287    __hash_const_iterator& operator=(const __hash_const_iterator& __i)
288    {
289        if (this != &__i)
290        {
291            __get_db()->__iterator_copy(this, &__i);
292            __node_ = __i.__node_;
293        }
294        return *this;
295    }
296
297#endif  // _LIBCPP_DEBUG_LEVEL >= 2
298
299    _LIBCPP_INLINE_VISIBILITY
300        reference operator*() const
301        {
302#if _LIBCPP_DEBUG_LEVEL >= 2
303            _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
304                           "Attempted to dereference a non-dereferenceable unordered container const_iterator");
305#endif
306            return __node_->__value_;
307        }
308    _LIBCPP_INLINE_VISIBILITY
309        pointer operator->() const
310        {
311#if _LIBCPP_DEBUG_LEVEL >= 2
312            _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
313                           "Attempted to dereference a non-dereferenceable unordered container const_iterator");
314#endif
315            return pointer_traits<pointer>::pointer_to(__node_->__value_);
316        }
317
318    _LIBCPP_INLINE_VISIBILITY
319    __hash_const_iterator& operator++()
320    {
321#if _LIBCPP_DEBUG_LEVEL >= 2
322        _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
323                       "Attempted to increment non-incrementable unordered container const_iterator");
324#endif
325        __node_ = __node_->__next_;
326        return *this;
327    }
328
329    _LIBCPP_INLINE_VISIBILITY
330    __hash_const_iterator operator++(int)
331    {
332        __hash_const_iterator __t(*this);
333        ++(*this);
334        return __t;
335    }
336
337    friend _LIBCPP_INLINE_VISIBILITY
338    bool operator==(const __hash_const_iterator& __x, const __hash_const_iterator& __y)
339    {
340        return __x.__node_ == __y.__node_;
341    }
342    friend _LIBCPP_INLINE_VISIBILITY
343    bool operator!=(const __hash_const_iterator& __x, const __hash_const_iterator& __y)
344        {return !(__x == __y);}
345
346private:
347#if _LIBCPP_DEBUG_LEVEL >= 2
348    _LIBCPP_INLINE_VISIBILITY
349    __hash_const_iterator(__node_pointer __node, const void* __c) _NOEXCEPT
350        : __node_(__node)
351        {
352            __get_db()->__insert_ic(this, __c);
353        }
354#else
355    _LIBCPP_INLINE_VISIBILITY
356    __hash_const_iterator(__node_pointer __node) _NOEXCEPT
357        : __node_(__node)
358        {}
359#endif
360
361    template <class, class, class, class> friend class __hash_table;
362    template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_map_const_iterator;
363    template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_map;
364    template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_multimap;
365};
366
367template <class _ConstNodePtr> class _LIBCPP_TYPE_VIS_ONLY __hash_const_local_iterator;
368
369template <class _NodePtr>
370class _LIBCPP_TYPE_VIS_ONLY __hash_local_iterator
371{
372    typedef _NodePtr __node_pointer;
373
374    __node_pointer         __node_;
375    size_t                 __bucket_;
376    size_t                 __bucket_count_;
377
378    typedef pointer_traits<__node_pointer>          __pointer_traits;
379public:
380    typedef forward_iterator_tag                                iterator_category;
381    typedef typename __pointer_traits::element_type::value_type value_type;
382    typedef typename __pointer_traits::difference_type          difference_type;
383    typedef value_type&                                         reference;
384    typedef typename __pointer_traits::template
385#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
386            rebind<value_type>
387#else
388            rebind<value_type>::other
389#endif
390                                                                pointer;
391
392    _LIBCPP_INLINE_VISIBILITY __hash_local_iterator() _NOEXCEPT
393    {
394#if _LIBCPP_DEBUG_LEVEL >= 2
395        __get_db()->__insert_i(this);
396#endif
397    }
398
399#if _LIBCPP_DEBUG_LEVEL >= 2
400
401    _LIBCPP_INLINE_VISIBILITY
402    __hash_local_iterator(const __hash_local_iterator& __i)
403        : __node_(__i.__node_),
404          __bucket_(__i.__bucket_),
405          __bucket_count_(__i.__bucket_count_)
406    {
407        __get_db()->__iterator_copy(this, &__i);
408    }
409
410    _LIBCPP_INLINE_VISIBILITY
411    ~__hash_local_iterator()
412    {
413        __get_db()->__erase_i(this);
414    }
415
416    _LIBCPP_INLINE_VISIBILITY
417    __hash_local_iterator& operator=(const __hash_local_iterator& __i)
418    {
419        if (this != &__i)
420        {
421            __get_db()->__iterator_copy(this, &__i);
422            __node_ = __i.__node_;
423            __bucket_ = __i.__bucket_;
424            __bucket_count_ = __i.__bucket_count_;
425        }
426        return *this;
427    }
428
429#endif  // _LIBCPP_DEBUG_LEVEL >= 2
430
431    _LIBCPP_INLINE_VISIBILITY
432        reference operator*() const
433        {
434#if _LIBCPP_DEBUG_LEVEL >= 2
435            _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
436                           "Attempted to dereference a non-dereferenceable unordered container local_iterator");
437#endif
438            return __node_->__value_;
439        }
440    _LIBCPP_INLINE_VISIBILITY
441        pointer operator->() const
442        {
443#if _LIBCPP_DEBUG_LEVEL >= 2
444            _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
445                           "Attempted to dereference a non-dereferenceable unordered container local_iterator");
446#endif
447            return pointer_traits<pointer>::pointer_to(__node_->__value_);
448        }
449
450    _LIBCPP_INLINE_VISIBILITY
451    __hash_local_iterator& operator++()
452    {
453#if _LIBCPP_DEBUG_LEVEL >= 2
454        _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
455                       "Attempted to increment non-incrementable unordered container local_iterator");
456#endif
457        __node_ = __node_->__next_;
458        if (__node_ != nullptr && __constrain_hash(__node_->__hash_, __bucket_count_) != __bucket_)
459            __node_ = nullptr;
460        return *this;
461    }
462
463    _LIBCPP_INLINE_VISIBILITY
464    __hash_local_iterator operator++(int)
465    {
466        __hash_local_iterator __t(*this);
467        ++(*this);
468        return __t;
469    }
470
471    friend _LIBCPP_INLINE_VISIBILITY
472    bool operator==(const __hash_local_iterator& __x, const __hash_local_iterator& __y)
473    {
474        return __x.__node_ == __y.__node_;
475    }
476    friend _LIBCPP_INLINE_VISIBILITY
477    bool operator!=(const __hash_local_iterator& __x, const __hash_local_iterator& __y)
478        {return !(__x == __y);}
479
480private:
481#if _LIBCPP_DEBUG_LEVEL >= 2
482    _LIBCPP_INLINE_VISIBILITY
483    __hash_local_iterator(__node_pointer __node, size_t __bucket,
484                          size_t __bucket_count, const void* __c) _NOEXCEPT
485        : __node_(__node),
486          __bucket_(__bucket),
487          __bucket_count_(__bucket_count)
488        {
489            __get_db()->__insert_ic(this, __c);
490            if (__node_ != nullptr)
491                __node_ = __node_->__next_;
492        }
493#else
494    _LIBCPP_INLINE_VISIBILITY
495    __hash_local_iterator(__node_pointer __node, size_t __bucket,
496                          size_t __bucket_count) _NOEXCEPT
497        : __node_(__node),
498          __bucket_(__bucket),
499          __bucket_count_(__bucket_count)
500        {
501            if (__node_ != nullptr)
502                __node_ = __node_->__next_;
503        }
504#endif
505    template <class, class, class, class> friend class __hash_table;
506    template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_const_local_iterator;
507    template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_map_iterator;
508};
509
510template <class _ConstNodePtr>
511class _LIBCPP_TYPE_VIS_ONLY __hash_const_local_iterator
512{
513    typedef _ConstNodePtr __node_pointer;
514
515    __node_pointer         __node_;
516    size_t                 __bucket_;
517    size_t                 __bucket_count_;
518
519    typedef pointer_traits<__node_pointer>          __pointer_traits;
520    typedef typename __pointer_traits::element_type __node;
521    typedef typename remove_const<__node>::type     __non_const_node;
522    typedef typename pointer_traits<__node_pointer>::template
523#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
524            rebind<__non_const_node>
525#else
526            rebind<__non_const_node>::other
527#endif
528                                                    __non_const_node_pointer;
529    typedef __hash_local_iterator<__non_const_node_pointer>
530                                                    __non_const_iterator;
531public:
532    typedef forward_iterator_tag                       iterator_category;
533    typedef typename remove_const<
534                        typename __pointer_traits::element_type::value_type
535                     >::type                           value_type;
536    typedef typename __pointer_traits::difference_type difference_type;
537    typedef const value_type&                          reference;
538    typedef typename __pointer_traits::template
539#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
540            rebind<const value_type>
541#else
542            rebind<const value_type>::other
543#endif
544                                                       pointer;
545
546    _LIBCPP_INLINE_VISIBILITY __hash_const_local_iterator() _NOEXCEPT
547    {
548#if _LIBCPP_DEBUG_LEVEL >= 2
549        __get_db()->__insert_i(this);
550#endif
551    }
552
553    _LIBCPP_INLINE_VISIBILITY
554    __hash_const_local_iterator(const __non_const_iterator& __x) _NOEXCEPT
555        : __node_(__x.__node_),
556          __bucket_(__x.__bucket_),
557          __bucket_count_(__x.__bucket_count_)
558    {
559#if _LIBCPP_DEBUG_LEVEL >= 2
560        __get_db()->__iterator_copy(this, &__x);
561#endif
562    }
563
564#if _LIBCPP_DEBUG_LEVEL >= 2
565
566    _LIBCPP_INLINE_VISIBILITY
567    __hash_const_local_iterator(const __hash_const_local_iterator& __i)
568        : __node_(__i.__node_),
569          __bucket_(__i.__bucket_),
570          __bucket_count_(__i.__bucket_count_)
571    {
572        __get_db()->__iterator_copy(this, &__i);
573    }
574
575    _LIBCPP_INLINE_VISIBILITY
576    ~__hash_const_local_iterator()
577    {
578        __get_db()->__erase_i(this);
579    }
580
581    _LIBCPP_INLINE_VISIBILITY
582    __hash_const_local_iterator& operator=(const __hash_const_local_iterator& __i)
583    {
584        if (this != &__i)
585        {
586            __get_db()->__iterator_copy(this, &__i);
587            __node_ = __i.__node_;
588            __bucket_ = __i.__bucket_;
589            __bucket_count_ = __i.__bucket_count_;
590        }
591        return *this;
592    }
593
594#endif  // _LIBCPP_DEBUG_LEVEL >= 2
595
596    _LIBCPP_INLINE_VISIBILITY
597        reference operator*() const
598        {
599#if _LIBCPP_DEBUG_LEVEL >= 2
600            _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
601                           "Attempted to dereference a non-dereferenceable unordered container const_local_iterator");
602#endif
603            return __node_->__value_;
604        }
605    _LIBCPP_INLINE_VISIBILITY
606        pointer operator->() const
607        {
608#if _LIBCPP_DEBUG_LEVEL >= 2
609            _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
610                           "Attempted to dereference a non-dereferenceable unordered container const_local_iterator");
611#endif
612            return pointer_traits<pointer>::pointer_to(__node_->__value_);
613        }
614
615    _LIBCPP_INLINE_VISIBILITY
616    __hash_const_local_iterator& operator++()
617    {
618#if _LIBCPP_DEBUG_LEVEL >= 2
619        _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
620                       "Attempted to increment non-incrementable unordered container const_local_iterator");
621#endif
622        __node_ = __node_->__next_;
623        if (__node_ != nullptr && __constrain_hash(__node_->__hash_, __bucket_count_) != __bucket_)
624            __node_ = nullptr;
625        return *this;
626    }
627
628    _LIBCPP_INLINE_VISIBILITY
629    __hash_const_local_iterator operator++(int)
630    {
631        __hash_const_local_iterator __t(*this);
632        ++(*this);
633        return __t;
634    }
635
636    friend _LIBCPP_INLINE_VISIBILITY
637    bool operator==(const __hash_const_local_iterator& __x, const __hash_const_local_iterator& __y)
638    {
639        return __x.__node_ == __y.__node_;
640    }
641    friend _LIBCPP_INLINE_VISIBILITY
642    bool operator!=(const __hash_const_local_iterator& __x, const __hash_const_local_iterator& __y)
643        {return !(__x == __y);}
644
645private:
646#if _LIBCPP_DEBUG_LEVEL >= 2
647    _LIBCPP_INLINE_VISIBILITY
648    __hash_const_local_iterator(__node_pointer __node, size_t __bucket,
649                                size_t __bucket_count, const void* __c) _NOEXCEPT
650        : __node_(__node),
651          __bucket_(__bucket),
652          __bucket_count_(__bucket_count)
653        {
654            __get_db()->__insert_ic(this, __c);
655            if (__node_ != nullptr)
656                __node_ = __node_->__next_;
657        }
658#else
659    _LIBCPP_INLINE_VISIBILITY
660    __hash_const_local_iterator(__node_pointer __node, size_t __bucket,
661                                size_t __bucket_count) _NOEXCEPT
662        : __node_(__node),
663          __bucket_(__bucket),
664          __bucket_count_(__bucket_count)
665        {
666            if (__node_ != nullptr)
667                __node_ = __node_->__next_;
668        }
669#endif
670    template <class, class, class, class> friend class __hash_table;
671    template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_map_const_iterator;
672};
673
674template <class _Alloc>
675class __bucket_list_deallocator
676{
677    typedef _Alloc                                          allocator_type;
678    typedef allocator_traits<allocator_type>                __alloc_traits;
679    typedef typename __alloc_traits::size_type              size_type;
680
681    __compressed_pair<size_type, allocator_type> __data_;
682public:
683    typedef typename __alloc_traits::pointer pointer;
684
685    _LIBCPP_INLINE_VISIBILITY
686    __bucket_list_deallocator()
687        _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
688        : __data_(0) {}
689
690    _LIBCPP_INLINE_VISIBILITY
691    __bucket_list_deallocator(const allocator_type& __a, size_type __size)
692        _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value)
693        : __data_(__size, __a) {}
694
695#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
696
697    _LIBCPP_INLINE_VISIBILITY
698    __bucket_list_deallocator(__bucket_list_deallocator&& __x)
699        _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
700        : __data_(_VSTD::move(__x.__data_))
701    {
702        __x.size() = 0;
703    }
704
705#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
706
707    _LIBCPP_INLINE_VISIBILITY
708    size_type& size() _NOEXCEPT {return __data_.first();}
709    _LIBCPP_INLINE_VISIBILITY
710    size_type  size() const _NOEXCEPT {return __data_.first();}
711
712    _LIBCPP_INLINE_VISIBILITY
713    allocator_type& __alloc() _NOEXCEPT {return __data_.second();}
714    _LIBCPP_INLINE_VISIBILITY
715    const allocator_type& __alloc() const _NOEXCEPT {return __data_.second();}
716
717    _LIBCPP_INLINE_VISIBILITY
718    void operator()(pointer __p) _NOEXCEPT
719    {
720        __alloc_traits::deallocate(__alloc(), __p, size());
721    }
722};
723
724template <class _Alloc> class __hash_map_node_destructor;
725
726template <class _Alloc>
727class __hash_node_destructor
728{
729    typedef _Alloc                                          allocator_type;
730    typedef allocator_traits<allocator_type>                __alloc_traits;
731    typedef typename __alloc_traits::value_type::value_type value_type;
732public:
733    typedef typename __alloc_traits::pointer                pointer;
734private:
735
736    allocator_type& __na_;
737
738    __hash_node_destructor& operator=(const __hash_node_destructor&);
739
740public:
741    bool __value_constructed;
742
743    _LIBCPP_INLINE_VISIBILITY
744    explicit __hash_node_destructor(allocator_type& __na,
745                                    bool __constructed = false) _NOEXCEPT
746        : __na_(__na),
747          __value_constructed(__constructed)
748        {}
749
750    _LIBCPP_INLINE_VISIBILITY
751    void operator()(pointer __p) _NOEXCEPT
752    {
753        if (__value_constructed)
754            __alloc_traits::destroy(__na_, _VSTD::addressof(__p->__value_));
755        if (__p)
756            __alloc_traits::deallocate(__na_, __p, 1);
757    }
758
759    template <class> friend class __hash_map_node_destructor;
760};
761
762template <class _Tp, class _Hash, class _Equal, class _Alloc>
763class __hash_table
764{
765public:
766    typedef _Tp    value_type;
767    typedef _Hash  hasher;
768    typedef _Equal key_equal;
769    typedef _Alloc allocator_type;
770
771private:
772    typedef allocator_traits<allocator_type> __alloc_traits;
773public:
774    typedef value_type&                              reference;
775    typedef const value_type&                        const_reference;
776    typedef typename __alloc_traits::pointer         pointer;
777    typedef typename __alloc_traits::const_pointer   const_pointer;
778    typedef typename __alloc_traits::size_type       size_type;
779    typedef typename __alloc_traits::difference_type difference_type;
780public:
781    // Create __node
782    typedef __hash_node<value_type, typename __alloc_traits::void_pointer> __node;
783    typedef typename __alloc_traits::template
784#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
785            rebind_alloc<__node>
786#else
787            rebind_alloc<__node>::other
788#endif
789                                                     __node_allocator;
790    typedef allocator_traits<__node_allocator>       __node_traits;
791    typedef typename __node_traits::pointer          __node_pointer;
792    typedef typename __node_traits::pointer          __node_const_pointer;
793    typedef __hash_node_base<__node_pointer>         __first_node;
794    typedef typename pointer_traits<__node_pointer>::template
795#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
796            rebind<__first_node>
797#else
798            rebind<__first_node>::other
799#endif
800                                                     __node_base_pointer;
801
802private:
803
804    typedef typename __node_traits::template
805#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
806            rebind_alloc<__node_pointer>
807#else
808            rebind_alloc<__node_pointer>::other
809#endif
810                                                            __pointer_allocator;
811    typedef __bucket_list_deallocator<__pointer_allocator> __bucket_list_deleter;
812    typedef unique_ptr<__node_pointer[], __bucket_list_deleter> __bucket_list;
813    typedef allocator_traits<__pointer_allocator>          __pointer_alloc_traits;
814    typedef typename __bucket_list_deleter::pointer __node_pointer_pointer;
815
816    // --- Member data begin ---
817    __bucket_list                                     __bucket_list_;
818    __compressed_pair<__first_node, __node_allocator> __p1_;
819    __compressed_pair<size_type, hasher>              __p2_;
820    __compressed_pair<float, key_equal>               __p3_;
821    // --- Member data end ---
822
823    _LIBCPP_INLINE_VISIBILITY
824    size_type& size() _NOEXCEPT {return __p2_.first();}
825public:
826    _LIBCPP_INLINE_VISIBILITY
827    size_type  size() const _NOEXCEPT {return __p2_.first();}
828
829    _LIBCPP_INLINE_VISIBILITY
830    hasher& hash_function() _NOEXCEPT {return __p2_.second();}
831    _LIBCPP_INLINE_VISIBILITY
832    const hasher& hash_function() const _NOEXCEPT {return __p2_.second();}
833
834    _LIBCPP_INLINE_VISIBILITY
835    float& max_load_factor() _NOEXCEPT {return __p3_.first();}
836    _LIBCPP_INLINE_VISIBILITY
837    float  max_load_factor() const _NOEXCEPT {return __p3_.first();}
838
839    _LIBCPP_INLINE_VISIBILITY
840    key_equal& key_eq() _NOEXCEPT {return __p3_.second();}
841    _LIBCPP_INLINE_VISIBILITY
842    const key_equal& key_eq() const _NOEXCEPT {return __p3_.second();}
843
844    _LIBCPP_INLINE_VISIBILITY
845    __node_allocator& __node_alloc() _NOEXCEPT {return __p1_.second();}
846    _LIBCPP_INLINE_VISIBILITY
847    const __node_allocator& __node_alloc() const _NOEXCEPT
848        {return __p1_.second();}
849
850public:
851    typedef __hash_iterator<__node_pointer>                   iterator;
852    typedef __hash_const_iterator<__node_pointer>             const_iterator;
853    typedef __hash_local_iterator<__node_pointer>             local_iterator;
854    typedef __hash_const_local_iterator<__node_pointer>       const_local_iterator;
855
856    __hash_table()
857        _NOEXCEPT_(
858            is_nothrow_default_constructible<__bucket_list>::value &&
859            is_nothrow_default_constructible<__first_node>::value &&
860            is_nothrow_default_constructible<__node_allocator>::value &&
861            is_nothrow_default_constructible<hasher>::value &&
862            is_nothrow_default_constructible<key_equal>::value);
863    __hash_table(const hasher& __hf, const key_equal& __eql);
864    __hash_table(const hasher& __hf, const key_equal& __eql,
865                 const allocator_type& __a);
866    explicit __hash_table(const allocator_type& __a);
867    __hash_table(const __hash_table& __u);
868    __hash_table(const __hash_table& __u, const allocator_type& __a);
869#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
870    __hash_table(__hash_table&& __u)
871        _NOEXCEPT_(
872            is_nothrow_move_constructible<__bucket_list>::value &&
873            is_nothrow_move_constructible<__first_node>::value &&
874            is_nothrow_move_constructible<__node_allocator>::value &&
875            is_nothrow_move_constructible<hasher>::value &&
876            is_nothrow_move_constructible<key_equal>::value);
877    __hash_table(__hash_table&& __u, const allocator_type& __a);
878#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
879    ~__hash_table();
880
881    __hash_table& operator=(const __hash_table& __u);
882#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
883    __hash_table& operator=(__hash_table&& __u)
884        _NOEXCEPT_(
885            __node_traits::propagate_on_container_move_assignment::value &&
886            is_nothrow_move_assignable<__node_allocator>::value &&
887            is_nothrow_move_assignable<hasher>::value &&
888            is_nothrow_move_assignable<key_equal>::value);
889#endif
890    template <class _InputIterator>
891        void __assign_unique(_InputIterator __first, _InputIterator __last);
892    template <class _InputIterator>
893        void __assign_multi(_InputIterator __first, _InputIterator __last);
894
895    _LIBCPP_INLINE_VISIBILITY
896    size_type max_size() const _NOEXCEPT
897    {
898        return allocator_traits<__pointer_allocator>::max_size(
899            __bucket_list_.get_deleter().__alloc());
900    }
901
902    pair<iterator, bool> __node_insert_unique(__node_pointer __nd);
903    iterator             __node_insert_multi(__node_pointer __nd);
904    iterator             __node_insert_multi(const_iterator __p,
905                                             __node_pointer __nd);
906
907#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
908    template <class... _Args>
909        pair<iterator, bool> __emplace_unique(_Args&&... __args);
910    template <class... _Args>
911        iterator __emplace_multi(_Args&&... __args);
912    template <class... _Args>
913        iterator __emplace_hint_multi(const_iterator __p, _Args&&... __args);
914#endif  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
915
916    pair<iterator, bool> __insert_unique(const value_type& __x);
917
918#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
919    template <class _Pp>
920        pair<iterator, bool> __insert_unique(_Pp&& __x);
921#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
922
923#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
924    template <class _Pp>
925        iterator __insert_multi(_Pp&& __x);
926    template <class _Pp>
927        iterator __insert_multi(const_iterator __p, _Pp&& __x);
928#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
929    iterator __insert_multi(const value_type& __x);
930    iterator __insert_multi(const_iterator __p, const value_type& __x);
931#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
932
933    void clear() _NOEXCEPT;
934    void rehash(size_type __n);
935    _LIBCPP_INLINE_VISIBILITY void reserve(size_type __n)
936        {rehash(static_cast<size_type>(ceil(__n / max_load_factor())));}
937
938    _LIBCPP_INLINE_VISIBILITY
939    size_type bucket_count() const _NOEXCEPT
940    {
941        return __bucket_list_.get_deleter().size();
942    }
943
944    iterator       begin() _NOEXCEPT;
945    iterator       end() _NOEXCEPT;
946    const_iterator begin() const _NOEXCEPT;
947    const_iterator end() const _NOEXCEPT;
948
949    template <class _Key>
950        _LIBCPP_INLINE_VISIBILITY
951        size_type bucket(const _Key& __k) const
952        {
953            _LIBCPP_ASSERT(bucket_count() > 0,
954                "unordered container::bucket(key) called when bucket_count() == 0");
955            return __constrain_hash(hash_function()(__k), bucket_count());
956        }
957
958    template <class _Key>
959        iterator       find(const _Key& __x);
960    template <class _Key>
961        const_iterator find(const _Key& __x) const;
962
963    typedef __hash_node_destructor<__node_allocator> _Dp;
964    typedef unique_ptr<__node, _Dp> __node_holder;
965
966    iterator erase(const_iterator __p);
967    iterator erase(const_iterator __first, const_iterator __last);
968    template <class _Key>
969        size_type __erase_unique(const _Key& __k);
970    template <class _Key>
971        size_type __erase_multi(const _Key& __k);
972    __node_holder remove(const_iterator __p) _NOEXCEPT;
973
974    template <class _Key>
975        size_type __count_unique(const _Key& __k) const;
976    template <class _Key>
977        size_type __count_multi(const _Key& __k) const;
978
979    template <class _Key>
980        pair<iterator, iterator>
981        __equal_range_unique(const _Key& __k);
982    template <class _Key>
983        pair<const_iterator, const_iterator>
984        __equal_range_unique(const _Key& __k) const;
985
986    template <class _Key>
987        pair<iterator, iterator>
988        __equal_range_multi(const _Key& __k);
989    template <class _Key>
990        pair<const_iterator, const_iterator>
991        __equal_range_multi(const _Key& __k) const;
992
993    void swap(__hash_table& __u)
994        _NOEXCEPT_(
995            (!allocator_traits<__pointer_allocator>::propagate_on_container_swap::value ||
996             __is_nothrow_swappable<__pointer_allocator>::value) &&
997            (!__node_traits::propagate_on_container_swap::value ||
998             __is_nothrow_swappable<__node_allocator>::value) &&
999            __is_nothrow_swappable<hasher>::value &&
1000            __is_nothrow_swappable<key_equal>::value);
1001
1002    _LIBCPP_INLINE_VISIBILITY
1003    size_type max_bucket_count() const _NOEXCEPT
1004        {return __pointer_alloc_traits::max_size(__bucket_list_.get_deleter().__alloc());}
1005    size_type bucket_size(size_type __n) const;
1006    _LIBCPP_INLINE_VISIBILITY float load_factor() const _NOEXCEPT
1007    {
1008        size_type __bc = bucket_count();
1009        return __bc != 0 ? (float)size() / __bc : 0.f;
1010    }
1011    _LIBCPP_INLINE_VISIBILITY void max_load_factor(float __mlf) _NOEXCEPT
1012    {
1013        _LIBCPP_ASSERT(__mlf > 0,
1014            "unordered container::max_load_factor(lf) called with lf <= 0");
1015        max_load_factor() = _VSTD::max(__mlf, load_factor());
1016    }
1017
1018    _LIBCPP_INLINE_VISIBILITY
1019    local_iterator
1020    begin(size_type __n)
1021    {
1022        _LIBCPP_ASSERT(__n < bucket_count(),
1023            "unordered container::begin(n) called with n >= bucket_count()");
1024#if _LIBCPP_DEBUG_LEVEL >= 2
1025        return local_iterator(__bucket_list_[__n], __n, bucket_count(), this);
1026#else
1027        return local_iterator(__bucket_list_[__n], __n, bucket_count());
1028#endif
1029    }
1030
1031    _LIBCPP_INLINE_VISIBILITY
1032    local_iterator
1033    end(size_type __n)
1034    {
1035        _LIBCPP_ASSERT(__n < bucket_count(),
1036            "unordered container::end(n) called with n >= bucket_count()");
1037#if _LIBCPP_DEBUG_LEVEL >= 2
1038        return local_iterator(nullptr, __n, bucket_count(), this);
1039#else
1040        return local_iterator(nullptr, __n, bucket_count());
1041#endif
1042    }
1043
1044    _LIBCPP_INLINE_VISIBILITY
1045    const_local_iterator
1046    cbegin(size_type __n) const
1047    {
1048        _LIBCPP_ASSERT(__n < bucket_count(),
1049            "unordered container::cbegin(n) called with n >= bucket_count()");
1050#if _LIBCPP_DEBUG_LEVEL >= 2
1051        return const_local_iterator(__bucket_list_[__n], __n, bucket_count(), this);
1052#else
1053        return const_local_iterator(__bucket_list_[__n], __n, bucket_count());
1054#endif
1055    }
1056
1057    _LIBCPP_INLINE_VISIBILITY
1058    const_local_iterator
1059    cend(size_type __n) const
1060    {
1061        _LIBCPP_ASSERT(__n < bucket_count(),
1062            "unordered container::cend(n) called with n >= bucket_count()");
1063#if _LIBCPP_DEBUG_LEVEL >= 2
1064        return const_local_iterator(nullptr, __n, bucket_count(), this);
1065#else
1066        return const_local_iterator(nullptr, __n, bucket_count());
1067#endif
1068    }
1069
1070#if _LIBCPP_DEBUG_LEVEL >= 2
1071
1072    bool __dereferenceable(const const_iterator* __i) const;
1073    bool __decrementable(const const_iterator* __i) const;
1074    bool __addable(const const_iterator* __i, ptrdiff_t __n) const;
1075    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const;
1076
1077#endif  // _LIBCPP_DEBUG_LEVEL >= 2
1078
1079private:
1080    void __rehash(size_type __n);
1081
1082#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1083#ifndef _LIBCPP_HAS_NO_VARIADICS
1084    template <class ..._Args>
1085        __node_holder __construct_node(_Args&& ...__args);
1086#endif  // _LIBCPP_HAS_NO_VARIADICS
1087    __node_holder __construct_node(value_type&& __v, size_t __hash);
1088#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1089    __node_holder __construct_node(const value_type& __v);
1090#endif
1091    __node_holder __construct_node(const value_type& __v, size_t __hash);
1092
1093    _LIBCPP_INLINE_VISIBILITY
1094    void __copy_assign_alloc(const __hash_table& __u)
1095        {__copy_assign_alloc(__u, integral_constant<bool,
1096             __node_traits::propagate_on_container_copy_assignment::value>());}
1097    void __copy_assign_alloc(const __hash_table& __u, true_type);
1098    _LIBCPP_INLINE_VISIBILITY
1099        void __copy_assign_alloc(const __hash_table&, false_type) {}
1100
1101    void __move_assign(__hash_table& __u, false_type);
1102    void __move_assign(__hash_table& __u, true_type)
1103        _NOEXCEPT_(
1104            is_nothrow_move_assignable<__node_allocator>::value &&
1105            is_nothrow_move_assignable<hasher>::value &&
1106            is_nothrow_move_assignable<key_equal>::value);
1107    _LIBCPP_INLINE_VISIBILITY
1108    void __move_assign_alloc(__hash_table& __u)
1109        _NOEXCEPT_(
1110            !__node_traits::propagate_on_container_move_assignment::value ||
1111            (is_nothrow_move_assignable<__pointer_allocator>::value &&
1112             is_nothrow_move_assignable<__node_allocator>::value))
1113        {__move_assign_alloc(__u, integral_constant<bool,
1114             __node_traits::propagate_on_container_move_assignment::value>());}
1115    _LIBCPP_INLINE_VISIBILITY
1116    void __move_assign_alloc(__hash_table& __u, true_type)
1117        _NOEXCEPT_(
1118            is_nothrow_move_assignable<__pointer_allocator>::value &&
1119            is_nothrow_move_assignable<__node_allocator>::value)
1120    {
1121        __bucket_list_.get_deleter().__alloc() =
1122                _VSTD::move(__u.__bucket_list_.get_deleter().__alloc());
1123        __node_alloc() = _VSTD::move(__u.__node_alloc());
1124    }
1125    _LIBCPP_INLINE_VISIBILITY
1126        void __move_assign_alloc(__hash_table&, false_type) _NOEXCEPT {}
1127
1128    template <class _Ap>
1129    _LIBCPP_INLINE_VISIBILITY
1130    static
1131    void
1132    __swap_alloc(_Ap& __x, _Ap& __y)
1133        _NOEXCEPT_(
1134            !allocator_traits<_Ap>::propagate_on_container_swap::value ||
1135            __is_nothrow_swappable<_Ap>::value)
1136    {
1137        __swap_alloc(__x, __y,
1138                     integral_constant<bool,
1139                        allocator_traits<_Ap>::propagate_on_container_swap::value
1140                                      >());
1141    }
1142
1143    template <class _Ap>
1144    _LIBCPP_INLINE_VISIBILITY
1145    static
1146    void
1147    __swap_alloc(_Ap& __x, _Ap& __y, true_type)
1148        _NOEXCEPT_(__is_nothrow_swappable<_Ap>::value)
1149    {
1150        using _VSTD::swap;
1151        swap(__x, __y);
1152    }
1153
1154    template <class _Ap>
1155    _LIBCPP_INLINE_VISIBILITY
1156    static
1157    void
1158    __swap_alloc(_Ap&, _Ap&, false_type) _NOEXCEPT {}
1159
1160    void __deallocate(__node_pointer __np) _NOEXCEPT;
1161    __node_pointer __detach() _NOEXCEPT;
1162
1163    template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_map;
1164    template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_multimap;
1165};
1166
1167template <class _Tp, class _Hash, class _Equal, class _Alloc>
1168inline _LIBCPP_INLINE_VISIBILITY
1169__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table()
1170    _NOEXCEPT_(
1171        is_nothrow_default_constructible<__bucket_list>::value &&
1172        is_nothrow_default_constructible<__first_node>::value &&
1173        is_nothrow_default_constructible<hasher>::value &&
1174        is_nothrow_default_constructible<key_equal>::value)
1175    : __p2_(0),
1176      __p3_(1.0f)
1177{
1178}
1179
1180template <class _Tp, class _Hash, class _Equal, class _Alloc>
1181inline _LIBCPP_INLINE_VISIBILITY
1182__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(const hasher& __hf,
1183                                                       const key_equal& __eql)
1184    : __bucket_list_(nullptr, __bucket_list_deleter()),
1185      __p1_(),
1186      __p2_(0, __hf),
1187      __p3_(1.0f, __eql)
1188{
1189}
1190
1191template <class _Tp, class _Hash, class _Equal, class _Alloc>
1192__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(const hasher& __hf,
1193                                                       const key_equal& __eql,
1194                                                       const allocator_type& __a)
1195    : __bucket_list_(nullptr, __bucket_list_deleter(__pointer_allocator(__a), 0)),
1196      __p1_(__node_allocator(__a)),
1197      __p2_(0, __hf),
1198      __p3_(1.0f, __eql)
1199{
1200}
1201
1202template <class _Tp, class _Hash, class _Equal, class _Alloc>
1203__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(const allocator_type& __a)
1204    : __bucket_list_(nullptr, __bucket_list_deleter(__pointer_allocator(__a), 0)),
1205      __p1_(__node_allocator(__a)),
1206      __p2_(0),
1207      __p3_(1.0f)
1208{
1209}
1210
1211template <class _Tp, class _Hash, class _Equal, class _Alloc>
1212__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(const __hash_table& __u)
1213    : __bucket_list_(nullptr,
1214          __bucket_list_deleter(allocator_traits<__pointer_allocator>::
1215              select_on_container_copy_construction(
1216                  __u.__bucket_list_.get_deleter().__alloc()), 0)),
1217      __p1_(allocator_traits<__node_allocator>::
1218          select_on_container_copy_construction(__u.__node_alloc())),
1219      __p2_(0, __u.hash_function()),
1220      __p3_(__u.__p3_)
1221{
1222}
1223
1224template <class _Tp, class _Hash, class _Equal, class _Alloc>
1225__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(const __hash_table& __u,
1226                                                       const allocator_type& __a)
1227    : __bucket_list_(nullptr, __bucket_list_deleter(__pointer_allocator(__a), 0)),
1228      __p1_(__node_allocator(__a)),
1229      __p2_(0, __u.hash_function()),
1230      __p3_(__u.__p3_)
1231{
1232}
1233
1234#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1235
1236template <class _Tp, class _Hash, class _Equal, class _Alloc>
1237__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(__hash_table&& __u)
1238        _NOEXCEPT_(
1239            is_nothrow_move_constructible<__bucket_list>::value &&
1240            is_nothrow_move_constructible<__first_node>::value &&
1241            is_nothrow_move_constructible<hasher>::value &&
1242            is_nothrow_move_constructible<key_equal>::value)
1243    : __bucket_list_(_VSTD::move(__u.__bucket_list_)),
1244      __p1_(_VSTD::move(__u.__p1_)),
1245      __p2_(_VSTD::move(__u.__p2_)),
1246      __p3_(_VSTD::move(__u.__p3_))
1247{
1248    if (size() > 0)
1249    {
1250        __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash_, bucket_count())] =
1251            static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
1252        __u.__p1_.first().__next_ = nullptr;
1253        __u.size() = 0;
1254    }
1255}
1256
1257template <class _Tp, class _Hash, class _Equal, class _Alloc>
1258__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(__hash_table&& __u,
1259                                                       const allocator_type& __a)
1260    : __bucket_list_(nullptr, __bucket_list_deleter(__pointer_allocator(__a), 0)),
1261      __p1_(__node_allocator(__a)),
1262      __p2_(0, _VSTD::move(__u.hash_function())),
1263      __p3_(_VSTD::move(__u.__p3_))
1264{
1265    if (__a == allocator_type(__u.__node_alloc()))
1266    {
1267        __bucket_list_.reset(__u.__bucket_list_.release());
1268        __bucket_list_.get_deleter().size() = __u.__bucket_list_.get_deleter().size();
1269        __u.__bucket_list_.get_deleter().size() = 0;
1270        if (__u.size() > 0)
1271        {
1272            __p1_.first().__next_ = __u.__p1_.first().__next_;
1273            __u.__p1_.first().__next_ = nullptr;
1274            __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash_, bucket_count())] =
1275                static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
1276            size() = __u.size();
1277            __u.size() = 0;
1278        }
1279    }
1280}
1281
1282#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1283
1284template <class _Tp, class _Hash, class _Equal, class _Alloc>
1285__hash_table<_Tp, _Hash, _Equal, _Alloc>::~__hash_table()
1286{
1287    __deallocate(__p1_.first().__next_);
1288#if _LIBCPP_DEBUG_LEVEL >= 2
1289    __get_db()->__erase_c(this);
1290#endif
1291}
1292
1293template <class _Tp, class _Hash, class _Equal, class _Alloc>
1294void
1295__hash_table<_Tp, _Hash, _Equal, _Alloc>::__copy_assign_alloc(
1296        const __hash_table& __u, true_type)
1297{
1298    if (__node_alloc() != __u.__node_alloc())
1299    {
1300        clear();
1301        __bucket_list_.reset();
1302        __bucket_list_.get_deleter().size() = 0;
1303    }
1304    __bucket_list_.get_deleter().__alloc() = __u.__bucket_list_.get_deleter().__alloc();
1305    __node_alloc() = __u.__node_alloc();
1306}
1307
1308template <class _Tp, class _Hash, class _Equal, class _Alloc>
1309__hash_table<_Tp, _Hash, _Equal, _Alloc>&
1310__hash_table<_Tp, _Hash, _Equal, _Alloc>::operator=(const __hash_table& __u)
1311{
1312    if (this != &__u)
1313    {
1314        __copy_assign_alloc(__u);
1315        hash_function() = __u.hash_function();
1316        key_eq() = __u.key_eq();
1317        max_load_factor() = __u.max_load_factor();
1318        __assign_multi(__u.begin(), __u.end());
1319    }
1320    return *this;
1321}
1322
1323template <class _Tp, class _Hash, class _Equal, class _Alloc>
1324void
1325__hash_table<_Tp, _Hash, _Equal, _Alloc>::__deallocate(__node_pointer __np)
1326    _NOEXCEPT
1327{
1328    __node_allocator& __na = __node_alloc();
1329    while (__np != nullptr)
1330    {
1331        __node_pointer __next = __np->__next_;
1332#if _LIBCPP_DEBUG_LEVEL >= 2
1333        __c_node* __c = __get_db()->__find_c_and_lock(this);
1334        for (__i_node** __p = __c->end_; __p != __c->beg_; )
1335        {
1336            --__p;
1337            iterator* __i = static_cast<iterator*>((*__p)->__i_);
1338            if (__i->__node_ == __np)
1339            {
1340                (*__p)->__c_ = nullptr;
1341                if (--__c->end_ != __p)
1342                    memmove(__p, __p+1, (__c->end_ - __p)*sizeof(__i_node*));
1343            }
1344        }
1345        __get_db()->unlock();
1346#endif
1347        __node_traits::destroy(__na, _VSTD::addressof(__np->__value_));
1348        __node_traits::deallocate(__na, __np, 1);
1349        __np = __next;
1350    }
1351}
1352
1353template <class _Tp, class _Hash, class _Equal, class _Alloc>
1354typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_pointer
1355__hash_table<_Tp, _Hash, _Equal, _Alloc>::__detach() _NOEXCEPT
1356{
1357    size_type __bc = bucket_count();
1358    for (size_type __i = 0; __i < __bc; ++__i)
1359        __bucket_list_[__i] = nullptr;
1360    size() = 0;
1361    __node_pointer __cache = __p1_.first().__next_;
1362    __p1_.first().__next_ = nullptr;
1363    return __cache;
1364}
1365
1366#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1367
1368template <class _Tp, class _Hash, class _Equal, class _Alloc>
1369void
1370__hash_table<_Tp, _Hash, _Equal, _Alloc>::__move_assign(
1371        __hash_table& __u, true_type)
1372    _NOEXCEPT_(
1373        is_nothrow_move_assignable<__node_allocator>::value &&
1374        is_nothrow_move_assignable<hasher>::value &&
1375        is_nothrow_move_assignable<key_equal>::value)
1376{
1377    clear();
1378    __bucket_list_.reset(__u.__bucket_list_.release());
1379    __bucket_list_.get_deleter().size() = __u.__bucket_list_.get_deleter().size();
1380    __u.__bucket_list_.get_deleter().size() = 0;
1381    __move_assign_alloc(__u);
1382    size() = __u.size();
1383    hash_function() = _VSTD::move(__u.hash_function());
1384    max_load_factor() = __u.max_load_factor();
1385    key_eq() = _VSTD::move(__u.key_eq());
1386    __p1_.first().__next_ = __u.__p1_.first().__next_;
1387    if (size() > 0)
1388    {
1389        __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash_, bucket_count())] =
1390            static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
1391        __u.__p1_.first().__next_ = nullptr;
1392        __u.size() = 0;
1393    }
1394#if _LIBCPP_DEBUG_LEVEL >= 2
1395    __get_db()->swap(this, &__u);
1396#endif
1397}
1398
1399template <class _Tp, class _Hash, class _Equal, class _Alloc>
1400void
1401__hash_table<_Tp, _Hash, _Equal, _Alloc>::__move_assign(
1402        __hash_table& __u, false_type)
1403{
1404    if (__node_alloc() == __u.__node_alloc())
1405        __move_assign(__u, true_type());
1406    else
1407    {
1408        hash_function() = _VSTD::move(__u.hash_function());
1409        key_eq() = _VSTD::move(__u.key_eq());
1410        max_load_factor() = __u.max_load_factor();
1411        if (bucket_count() != 0)
1412        {
1413            __node_pointer __cache = __detach();
1414#ifndef _LIBCPP_NO_EXCEPTIONS
1415            try
1416            {
1417#endif  // _LIBCPP_NO_EXCEPTIONS
1418                const_iterator __i = __u.begin();
1419                while (__cache != nullptr && __u.size() != 0)
1420                {
1421                    __cache->__value_ = _VSTD::move(__u.remove(__i++)->__value_);
1422                    __node_pointer __next = __cache->__next_;
1423                    __node_insert_multi(__cache);
1424                    __cache = __next;
1425                }
1426#ifndef _LIBCPP_NO_EXCEPTIONS
1427            }
1428            catch (...)
1429            {
1430                __deallocate(__cache);
1431                throw;
1432            }
1433#endif  // _LIBCPP_NO_EXCEPTIONS
1434            __deallocate(__cache);
1435        }
1436        const_iterator __i = __u.begin();
1437        while (__u.size() != 0)
1438        {
1439            __node_holder __h =
1440                    __construct_node(_VSTD::move(__u.remove(__i++)->__value_));
1441            __node_insert_multi(__h.get());
1442            __h.release();
1443        }
1444    }
1445}
1446
1447template <class _Tp, class _Hash, class _Equal, class _Alloc>
1448inline _LIBCPP_INLINE_VISIBILITY
1449__hash_table<_Tp, _Hash, _Equal, _Alloc>&
1450__hash_table<_Tp, _Hash, _Equal, _Alloc>::operator=(__hash_table&& __u)
1451    _NOEXCEPT_(
1452        __node_traits::propagate_on_container_move_assignment::value &&
1453        is_nothrow_move_assignable<__node_allocator>::value &&
1454        is_nothrow_move_assignable<hasher>::value &&
1455        is_nothrow_move_assignable<key_equal>::value)
1456{
1457    __move_assign(__u, integral_constant<bool,
1458                  __node_traits::propagate_on_container_move_assignment::value>());
1459    return *this;
1460}
1461
1462#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1463
1464template <class _Tp, class _Hash, class _Equal, class _Alloc>
1465template <class _InputIterator>
1466void
1467__hash_table<_Tp, _Hash, _Equal, _Alloc>::__assign_unique(_InputIterator __first,
1468                                                          _InputIterator __last)
1469{
1470    if (bucket_count() != 0)
1471    {
1472        __node_pointer __cache = __detach();
1473#ifndef _LIBCPP_NO_EXCEPTIONS
1474        try
1475        {
1476#endif  // _LIBCPP_NO_EXCEPTIONS
1477            for (; __cache != nullptr && __first != __last; ++__first)
1478            {
1479                __cache->__value_ = *__first;
1480                __node_pointer __next = __cache->__next_;
1481                __node_insert_unique(__cache);
1482                __cache = __next;
1483            }
1484#ifndef _LIBCPP_NO_EXCEPTIONS
1485        }
1486        catch (...)
1487        {
1488            __deallocate(__cache);
1489            throw;
1490        }
1491#endif  // _LIBCPP_NO_EXCEPTIONS
1492        __deallocate(__cache);
1493    }
1494    for (; __first != __last; ++__first)
1495        __insert_unique(*__first);
1496}
1497
1498template <class _Tp, class _Hash, class _Equal, class _Alloc>
1499template <class _InputIterator>
1500void
1501__hash_table<_Tp, _Hash, _Equal, _Alloc>::__assign_multi(_InputIterator __first,
1502                                                         _InputIterator __last)
1503{
1504    if (bucket_count() != 0)
1505    {
1506        __node_pointer __cache = __detach();
1507#ifndef _LIBCPP_NO_EXCEPTIONS
1508        try
1509        {
1510#endif  // _LIBCPP_NO_EXCEPTIONS
1511            for (; __cache != nullptr && __first != __last; ++__first)
1512            {
1513                __cache->__value_ = *__first;
1514                __node_pointer __next = __cache->__next_;
1515                __node_insert_multi(__cache);
1516                __cache = __next;
1517            }
1518#ifndef _LIBCPP_NO_EXCEPTIONS
1519        }
1520        catch (...)
1521        {
1522            __deallocate(__cache);
1523            throw;
1524        }
1525#endif  // _LIBCPP_NO_EXCEPTIONS
1526        __deallocate(__cache);
1527    }
1528    for (; __first != __last; ++__first)
1529        __insert_multi(*__first);
1530}
1531
1532template <class _Tp, class _Hash, class _Equal, class _Alloc>
1533inline _LIBCPP_INLINE_VISIBILITY
1534typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
1535__hash_table<_Tp, _Hash, _Equal, _Alloc>::begin() _NOEXCEPT
1536{
1537#if _LIBCPP_DEBUG_LEVEL >= 2
1538    return iterator(__p1_.first().__next_, this);
1539#else
1540    return iterator(__p1_.first().__next_);
1541#endif
1542}
1543
1544template <class _Tp, class _Hash, class _Equal, class _Alloc>
1545inline _LIBCPP_INLINE_VISIBILITY
1546typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
1547__hash_table<_Tp, _Hash, _Equal, _Alloc>::end() _NOEXCEPT
1548{
1549#if _LIBCPP_DEBUG_LEVEL >= 2
1550    return iterator(nullptr, this);
1551#else
1552    return iterator(nullptr);
1553#endif
1554}
1555
1556template <class _Tp, class _Hash, class _Equal, class _Alloc>
1557inline _LIBCPP_INLINE_VISIBILITY
1558typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator
1559__hash_table<_Tp, _Hash, _Equal, _Alloc>::begin() const _NOEXCEPT
1560{
1561#if _LIBCPP_DEBUG_LEVEL >= 2
1562    return const_iterator(__p1_.first().__next_, this);
1563#else
1564    return const_iterator(__p1_.first().__next_);
1565#endif
1566}
1567
1568template <class _Tp, class _Hash, class _Equal, class _Alloc>
1569inline _LIBCPP_INLINE_VISIBILITY
1570typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator
1571__hash_table<_Tp, _Hash, _Equal, _Alloc>::end() const _NOEXCEPT
1572{
1573#if _LIBCPP_DEBUG_LEVEL >= 2
1574    return const_iterator(nullptr, this);
1575#else
1576    return const_iterator(nullptr);
1577#endif
1578}
1579
1580template <class _Tp, class _Hash, class _Equal, class _Alloc>
1581void
1582__hash_table<_Tp, _Hash, _Equal, _Alloc>::clear() _NOEXCEPT
1583{
1584    if (size() > 0)
1585    {
1586        __deallocate(__p1_.first().__next_);
1587        __p1_.first().__next_ = nullptr;
1588        size_type __bc = bucket_count();
1589        for (size_type __i = 0; __i < __bc; ++__i)
1590            __bucket_list_[__i] = nullptr;
1591        size() = 0;
1592    }
1593}
1594
1595template <class _Tp, class _Hash, class _Equal, class _Alloc>
1596pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator, bool>
1597__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_unique(__node_pointer __nd)
1598{
1599    __nd->__hash_ = hash_function()(__nd->__value_);
1600    size_type __bc = bucket_count();
1601    bool __inserted = false;
1602    __node_pointer __ndptr;
1603    size_t __chash;
1604    if (__bc != 0)
1605    {
1606        __chash = __constrain_hash(__nd->__hash_, __bc);
1607        __ndptr = __bucket_list_[__chash];
1608        if (__ndptr != nullptr)
1609        {
1610            for (__ndptr = __ndptr->__next_; __ndptr != nullptr &&
1611                                             __constrain_hash(__ndptr->__hash_, __bc) == __chash;
1612                                                     __ndptr = __ndptr->__next_)
1613            {
1614                if (key_eq()(__ndptr->__value_, __nd->__value_))
1615                    goto __done;
1616            }
1617        }
1618    }
1619    {
1620        if (size()+1 > __bc * max_load_factor() || __bc == 0)
1621        {
1622            rehash(_VSTD::max<size_type>(2 * __bc + !__is_power2(__bc),
1623                           size_type(ceil(float(size() + 1) / max_load_factor()))));
1624            __bc = bucket_count();
1625            __chash = __constrain_hash(__nd->__hash_, __bc);
1626        }
1627        // insert_after __bucket_list_[__chash], or __first_node if bucket is null
1628        __node_pointer __pn = __bucket_list_[__chash];
1629        if (__pn == nullptr)
1630        {
1631            __pn = static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
1632            __nd->__next_ = __pn->__next_;
1633            __pn->__next_ = __nd;
1634            // fix up __bucket_list_
1635            __bucket_list_[__chash] = __pn;
1636            if (__nd->__next_ != nullptr)
1637                __bucket_list_[__constrain_hash(__nd->__next_->__hash_, __bc)] = __nd;
1638        }
1639        else
1640        {
1641            __nd->__next_ = __pn->__next_;
1642            __pn->__next_ = __nd;
1643        }
1644        __ndptr = __nd;
1645        // increment size
1646        ++size();
1647        __inserted = true;
1648    }
1649__done:
1650#if _LIBCPP_DEBUG_LEVEL >= 2
1651    return pair<iterator, bool>(iterator(__ndptr, this), __inserted);
1652#else
1653    return pair<iterator, bool>(iterator(__ndptr), __inserted);
1654#endif
1655}
1656
1657template <class _Tp, class _Hash, class _Equal, class _Alloc>
1658typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
1659__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi(__node_pointer __cp)
1660{
1661    __cp->__hash_ = hash_function()(__cp->__value_);
1662    size_type __bc = bucket_count();
1663    if (size()+1 > __bc * max_load_factor() || __bc == 0)
1664    {
1665        rehash(_VSTD::max<size_type>(2 * __bc + !__is_power2(__bc),
1666                       size_type(ceil(float(size() + 1) / max_load_factor()))));
1667        __bc = bucket_count();
1668    }
1669    size_t __chash = __constrain_hash(__cp->__hash_, __bc);
1670    __node_pointer __pn = __bucket_list_[__chash];
1671    if (__pn == nullptr)
1672    {
1673        __pn = static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
1674        __cp->__next_ = __pn->__next_;
1675        __pn->__next_ = __cp;
1676        // fix up __bucket_list_
1677        __bucket_list_[__chash] = __pn;
1678        if (__cp->__next_ != nullptr)
1679            __bucket_list_[__constrain_hash(__cp->__next_->__hash_, __bc)] = __cp;
1680    }
1681    else
1682    {
1683        for (bool __found = false; __pn->__next_ != nullptr &&
1684                                   __constrain_hash(__pn->__next_->__hash_, __bc) == __chash;
1685                                                           __pn = __pn->__next_)
1686        {
1687            //      __found    key_eq()     action
1688            //      false       false       loop
1689            //      true        true        loop
1690            //      false       true        set __found to true
1691            //      true        false       break
1692            if (__found != (__pn->__next_->__hash_ == __cp->__hash_ &&
1693                            key_eq()(__pn->__next_->__value_, __cp->__value_)))
1694            {
1695                if (!__found)
1696                    __found = true;
1697                else
1698                    break;
1699            }
1700        }
1701        __cp->__next_ = __pn->__next_;
1702        __pn->__next_ = __cp;
1703        if (__cp->__next_ != nullptr)
1704        {
1705            size_t __nhash = __constrain_hash(__cp->__next_->__hash_, __bc);
1706            if (__nhash != __chash)
1707                __bucket_list_[__nhash] = __cp;
1708        }
1709    }
1710    ++size();
1711#if _LIBCPP_DEBUG_LEVEL >= 2
1712    return iterator(__cp, this);
1713#else
1714    return iterator(__cp);
1715#endif
1716}
1717
1718template <class _Tp, class _Hash, class _Equal, class _Alloc>
1719typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
1720__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi(
1721        const_iterator __p, __node_pointer __cp)
1722{
1723#if _LIBCPP_DEBUG_LEVEL >= 2
1724    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
1725        "unordered container::emplace_hint(const_iterator, args...) called with an iterator not"
1726        " referring to this unordered container");
1727#endif
1728    if (__p != end() && key_eq()(*__p, __cp->__value_))
1729    {
1730        __node_pointer __np = __p.__node_;
1731        __cp->__hash_ = __np->__hash_;
1732        size_type __bc = bucket_count();
1733        if (size()+1 > __bc * max_load_factor() || __bc == 0)
1734        {
1735            rehash(_VSTD::max<size_type>(2 * __bc + !__is_power2(__bc),
1736                           size_type(ceil(float(size() + 1) / max_load_factor()))));
1737            __bc = bucket_count();
1738        }
1739        size_t __chash = __constrain_hash(__cp->__hash_, __bc);
1740        __node_pointer __pp = __bucket_list_[__chash];
1741        while (__pp->__next_ != __np)
1742            __pp = __pp->__next_;
1743        __cp->__next_ = __np;
1744        __pp->__next_ = __cp;
1745        ++size();
1746#if _LIBCPP_DEBUG_LEVEL >= 2
1747        return iterator(__cp, this);
1748#else
1749        return iterator(__cp);
1750#endif
1751    }
1752    return __node_insert_multi(__cp);
1753}
1754
1755template <class _Tp, class _Hash, class _Equal, class _Alloc>
1756pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator, bool>
1757__hash_table<_Tp, _Hash, _Equal, _Alloc>::__insert_unique(const value_type& __x)
1758{
1759    size_t __hash = hash_function()(__x);
1760    size_type __bc = bucket_count();
1761    bool __inserted = false;
1762    __node_pointer __nd;
1763    size_t __chash;
1764    if (__bc != 0)
1765    {
1766        __chash = __constrain_hash(__hash, __bc);
1767        __nd = __bucket_list_[__chash];
1768        if (__nd != nullptr)
1769        {
1770            for (__nd = __nd->__next_; __nd != nullptr &&
1771                                       __constrain_hash(__nd->__hash_, __bc) == __chash;
1772                                                           __nd = __nd->__next_)
1773            {
1774                if (key_eq()(__nd->__value_, __x))
1775                    goto __done;
1776            }
1777        }
1778    }
1779    {
1780        __node_holder __h = __construct_node(__x, __hash);
1781        if (size()+1 > __bc * max_load_factor() || __bc == 0)
1782        {
1783            rehash(_VSTD::max<size_type>(2 * __bc + !__is_power2(__bc),
1784                           size_type(ceil(float(size() + 1) / max_load_factor()))));
1785            __bc = bucket_count();
1786            __chash = __constrain_hash(__hash, __bc);
1787        }
1788        // insert_after __bucket_list_[__chash], or __first_node if bucket is null
1789        __node_pointer __pn = __bucket_list_[__chash];
1790        if (__pn == nullptr)
1791        {
1792            __pn = static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
1793            __h->__next_ = __pn->__next_;
1794            __pn->__next_ = __h.get();
1795            // fix up __bucket_list_
1796            __bucket_list_[__chash] = __pn;
1797            if (__h->__next_ != nullptr)
1798                __bucket_list_[__constrain_hash(__h->__next_->__hash_, __bc)] = __h.get();
1799        }
1800        else
1801        {
1802            __h->__next_ = __pn->__next_;
1803            __pn->__next_ = __h.get();
1804        }
1805        __nd = __h.release();
1806        // increment size
1807        ++size();
1808        __inserted = true;
1809    }
1810__done:
1811#if _LIBCPP_DEBUG_LEVEL >= 2
1812    return pair<iterator, bool>(iterator(__nd, this), __inserted);
1813#else
1814    return pair<iterator, bool>(iterator(__nd), __inserted);
1815#endif
1816}
1817
1818#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1819#ifndef _LIBCPP_HAS_NO_VARIADICS
1820
1821template <class _Tp, class _Hash, class _Equal, class _Alloc>
1822template <class... _Args>
1823pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator, bool>
1824__hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_unique(_Args&&... __args)
1825{
1826    __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
1827    pair<iterator, bool> __r = __node_insert_unique(__h.get());
1828    if (__r.second)
1829        __h.release();
1830    return __r;
1831}
1832
1833template <class _Tp, class _Hash, class _Equal, class _Alloc>
1834template <class... _Args>
1835typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
1836__hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_multi(_Args&&... __args)
1837{
1838    __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
1839    iterator __r = __node_insert_multi(__h.get());
1840    __h.release();
1841    return __r;
1842}
1843
1844template <class _Tp, class _Hash, class _Equal, class _Alloc>
1845template <class... _Args>
1846typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
1847__hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_hint_multi(
1848        const_iterator __p, _Args&&... __args)
1849{
1850#if _LIBCPP_DEBUG_LEVEL >= 2
1851    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
1852        "unordered container::emplace_hint(const_iterator, args...) called with an iterator not"
1853        " referring to this unordered container");
1854#endif
1855    __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
1856    iterator __r = __node_insert_multi(__p, __h.get());
1857    __h.release();
1858    return __r;
1859}
1860
1861#endif  // _LIBCPP_HAS_NO_VARIADICS
1862
1863template <class _Tp, class _Hash, class _Equal, class _Alloc>
1864template <class _Pp>
1865pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator, bool>
1866__hash_table<_Tp, _Hash, _Equal, _Alloc>::__insert_unique(_Pp&& __x)
1867{
1868    __node_holder __h = __construct_node(_VSTD::forward<_Pp>(__x));
1869    pair<iterator, bool> __r = __node_insert_unique(__h.get());
1870    if (__r.second)
1871        __h.release();
1872    return __r;
1873}
1874
1875#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1876
1877#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1878
1879template <class _Tp, class _Hash, class _Equal, class _Alloc>
1880template <class _Pp>
1881typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
1882__hash_table<_Tp, _Hash, _Equal, _Alloc>::__insert_multi(_Pp&& __x)
1883{
1884    __node_holder __h = __construct_node(_VSTD::forward<_Pp>(__x));
1885    iterator __r = __node_insert_multi(__h.get());
1886    __h.release();
1887    return __r;
1888}
1889
1890template <class _Tp, class _Hash, class _Equal, class _Alloc>
1891template <class _Pp>
1892typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
1893__hash_table<_Tp, _Hash, _Equal, _Alloc>::__insert_multi(const_iterator __p,
1894                                                         _Pp&& __x)
1895{
1896#if _LIBCPP_DEBUG_LEVEL >= 2
1897    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
1898        "unordered container::insert(const_iterator, rvalue) called with an iterator not"
1899        " referring to this unordered container");
1900#endif
1901    __node_holder __h = __construct_node(_VSTD::forward<_Pp>(__x));
1902    iterator __r = __node_insert_multi(__p, __h.get());
1903    __h.release();
1904    return __r;
1905}
1906
1907#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1908
1909template <class _Tp, class _Hash, class _Equal, class _Alloc>
1910typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
1911__hash_table<_Tp, _Hash, _Equal, _Alloc>::__insert_multi(const value_type& __x)
1912{
1913    __node_holder __h = __construct_node(__x);
1914    iterator __r = __node_insert_multi(__h.get());
1915    __h.release();
1916    return __r;
1917}
1918
1919template <class _Tp, class _Hash, class _Equal, class _Alloc>
1920typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
1921__hash_table<_Tp, _Hash, _Equal, _Alloc>::__insert_multi(const_iterator __p,
1922                                                         const value_type& __x)
1923{
1924#if _LIBCPP_DEBUG_LEVEL >= 2
1925    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
1926        "unordered container::insert(const_iterator, lvalue) called with an iterator not"
1927        " referring to this unordered container");
1928#endif
1929    __node_holder __h = __construct_node(__x);
1930    iterator __r = __node_insert_multi(__p, __h.get());
1931    __h.release();
1932    return __r;
1933}
1934
1935#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1936
1937template <class _Tp, class _Hash, class _Equal, class _Alloc>
1938void
1939__hash_table<_Tp, _Hash, _Equal, _Alloc>::rehash(size_type __n)
1940{
1941    if (__n == 1)
1942        __n = 2;
1943    else if (__n & (__n - 1))
1944        __n = __next_prime(__n);
1945    size_type __bc = bucket_count();
1946    if (__n > __bc)
1947        __rehash(__n);
1948    else if (__n < __bc)
1949    {
1950        __n = _VSTD::max<size_type>
1951              (
1952                  __n,
1953                  __is_power2(__bc) ? __next_pow2(size_t(ceil(float(size()) / max_load_factor()))) :
1954                                      __next_prime(size_t(ceil(float(size()) / max_load_factor())))
1955              );
1956        if (__n < __bc)
1957            __rehash(__n);
1958    }
1959}
1960
1961template <class _Tp, class _Hash, class _Equal, class _Alloc>
1962void
1963__hash_table<_Tp, _Hash, _Equal, _Alloc>::__rehash(size_type __nbc)
1964{
1965#if _LIBCPP_DEBUG_LEVEL >= 2
1966    __get_db()->__invalidate_all(this);
1967#endif  // _LIBCPP_DEBUG_LEVEL >= 2
1968    __pointer_allocator& __npa = __bucket_list_.get_deleter().__alloc();
1969    __bucket_list_.reset(__nbc > 0 ?
1970                      __pointer_alloc_traits::allocate(__npa, __nbc) : nullptr);
1971    __bucket_list_.get_deleter().size() = __nbc;
1972    if (__nbc > 0)
1973    {
1974        for (size_type __i = 0; __i < __nbc; ++__i)
1975            __bucket_list_[__i] = nullptr;
1976        __node_pointer __pp(static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first())));
1977        __node_pointer __cp = __pp->__next_;
1978        if (__cp != nullptr)
1979        {
1980            size_type __chash = __constrain_hash(__cp->__hash_, __nbc);
1981            __bucket_list_[__chash] = __pp;
1982            size_type __phash = __chash;
1983            for (__pp = __cp, __cp = __cp->__next_; __cp != nullptr;
1984                                                           __cp = __pp->__next_)
1985            {
1986                __chash = __constrain_hash(__cp->__hash_, __nbc);
1987                if (__chash == __phash)
1988                    __pp = __cp;
1989                else
1990                {
1991                    if (__bucket_list_[__chash] == nullptr)
1992                    {
1993                        __bucket_list_[__chash] = __pp;
1994                        __pp = __cp;
1995                        __phash = __chash;
1996                    }
1997                    else
1998                    {
1999                        __node_pointer __np = __cp;
2000                        for (; __np->__next_ != nullptr &&
2001                               key_eq()(__cp->__value_, __np->__next_->__value_);
2002                                                           __np = __np->__next_)
2003                            ;
2004                        __pp->__next_ = __np->__next_;
2005                        __np->__next_ = __bucket_list_[__chash]->__next_;
2006                        __bucket_list_[__chash]->__next_ = __cp;
2007
2008                    }
2009                }
2010            }
2011        }
2012    }
2013}
2014
2015template <class _Tp, class _Hash, class _Equal, class _Alloc>
2016template <class _Key>
2017typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
2018__hash_table<_Tp, _Hash, _Equal, _Alloc>::find(const _Key& __k)
2019{
2020    size_t __hash = hash_function()(__k);
2021    size_type __bc = bucket_count();
2022    if (__bc != 0)
2023    {
2024        size_t __chash = __constrain_hash(__hash, __bc);
2025        __node_pointer __nd = __bucket_list_[__chash];
2026        if (__nd != nullptr)
2027        {
2028            for (__nd = __nd->__next_; __nd != nullptr &&
2029                                       __constrain_hash(__nd->__hash_, __bc) == __chash;
2030                                                           __nd = __nd->__next_)
2031            {
2032                if (key_eq()(__nd->__value_, __k))
2033#if _LIBCPP_DEBUG_LEVEL >= 2
2034                    return iterator(__nd, this);
2035#else
2036                    return iterator(__nd);
2037#endif
2038            }
2039        }
2040    }
2041    return end();
2042}
2043
2044template <class _Tp, class _Hash, class _Equal, class _Alloc>
2045template <class _Key>
2046typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator
2047__hash_table<_Tp, _Hash, _Equal, _Alloc>::find(const _Key& __k) const
2048{
2049    size_t __hash = hash_function()(__k);
2050    size_type __bc = bucket_count();
2051    if (__bc != 0)
2052    {
2053        size_t __chash = __constrain_hash(__hash, __bc);
2054        __node_const_pointer __nd = __bucket_list_[__chash];
2055        if (__nd != nullptr)
2056        {
2057            for (__nd = __nd->__next_; __nd != nullptr &&
2058                                           __constrain_hash(__nd->__hash_, __bc) == __chash;
2059                                                           __nd = __nd->__next_)
2060            {
2061                if (key_eq()(__nd->__value_, __k))
2062#if _LIBCPP_DEBUG_LEVEL >= 2
2063                    return const_iterator(__nd, this);
2064#else
2065                    return const_iterator(__nd);
2066#endif
2067            }
2068        }
2069
2070    }
2071    return end();
2072}
2073
2074#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2075#ifndef _LIBCPP_HAS_NO_VARIADICS
2076
2077template <class _Tp, class _Hash, class _Equal, class _Alloc>
2078template <class ..._Args>
2079typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_holder
2080__hash_table<_Tp, _Hash, _Equal, _Alloc>::__construct_node(_Args&& ...__args)
2081{
2082    __node_allocator& __na = __node_alloc();
2083    __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
2084    __node_traits::construct(__na, _VSTD::addressof(__h->__value_), _VSTD::forward<_Args>(__args)...);
2085    __h.get_deleter().__value_constructed = true;
2086    __h->__hash_ = hash_function()(__h->__value_);
2087    __h->__next_ = nullptr;
2088    return __h;
2089}
2090
2091#endif  // _LIBCPP_HAS_NO_VARIADICS
2092
2093template <class _Tp, class _Hash, class _Equal, class _Alloc>
2094typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_holder
2095__hash_table<_Tp, _Hash, _Equal, _Alloc>::__construct_node(value_type&& __v,
2096                                                           size_t __hash)
2097{
2098    __node_allocator& __na = __node_alloc();
2099    __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
2100    __node_traits::construct(__na, _VSTD::addressof(__h->__value_), _VSTD::move(__v));
2101    __h.get_deleter().__value_constructed = true;
2102    __h->__hash_ = __hash;
2103    __h->__next_ = nullptr;
2104    return __h;
2105}
2106
2107#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2108
2109template <class _Tp, class _Hash, class _Equal, class _Alloc>
2110typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_holder
2111__hash_table<_Tp, _Hash, _Equal, _Alloc>::__construct_node(const value_type& __v)
2112{
2113    __node_allocator& __na = __node_alloc();
2114    __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
2115    __node_traits::construct(__na, _VSTD::addressof(__h->__value_), __v);
2116    __h.get_deleter().__value_constructed = true;
2117    __h->__hash_ = hash_function()(__h->__value_);
2118    __h->__next_ = nullptr;
2119    return _VSTD::move(__h);  // explicitly moved for C++03
2120}
2121
2122#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2123
2124template <class _Tp, class _Hash, class _Equal, class _Alloc>
2125typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_holder
2126__hash_table<_Tp, _Hash, _Equal, _Alloc>::__construct_node(const value_type& __v,
2127                                                           size_t __hash)
2128{
2129    __node_allocator& __na = __node_alloc();
2130    __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
2131    __node_traits::construct(__na, _VSTD::addressof(__h->__value_), __v);
2132    __h.get_deleter().__value_constructed = true;
2133    __h->__hash_ = __hash;
2134    __h->__next_ = nullptr;
2135    return _VSTD::move(__h);  // explicitly moved for C++03
2136}
2137
2138template <class _Tp, class _Hash, class _Equal, class _Alloc>
2139typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
2140__hash_table<_Tp, _Hash, _Equal, _Alloc>::erase(const_iterator __p)
2141{
2142    __node_pointer __np = __p.__node_;
2143#if _LIBCPP_DEBUG_LEVEL >= 2
2144    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
2145        "unordered container erase(iterator) called with an iterator not"
2146        " referring to this container");
2147    _LIBCPP_ASSERT(__p != end(),
2148        "unordered container erase(iterator) called with a non-dereferenceable iterator");
2149    iterator __r(__np, this);
2150#else
2151    iterator __r(__np);
2152#endif
2153    ++__r;
2154    remove(__p);
2155    return __r;
2156}
2157
2158template <class _Tp, class _Hash, class _Equal, class _Alloc>
2159typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
2160__hash_table<_Tp, _Hash, _Equal, _Alloc>::erase(const_iterator __first,
2161                                                const_iterator __last)
2162{
2163#if _LIBCPP_DEBUG_LEVEL >= 2
2164    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__first) == this,
2165        "unodered container::erase(iterator, iterator) called with an iterator not"
2166        " referring to this unodered container");
2167    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__last) == this,
2168        "unodered container::erase(iterator, iterator) called with an iterator not"
2169        " referring to this unodered container");
2170#endif
2171    for (const_iterator __p = __first; __first != __last; __p = __first)
2172    {
2173        ++__first;
2174        erase(__p);
2175    }
2176    __node_pointer __np = __last.__node_;
2177#if _LIBCPP_DEBUG_LEVEL >= 2
2178    return iterator (__np, this);
2179#else
2180    return iterator (__np);
2181#endif
2182}
2183
2184template <class _Tp, class _Hash, class _Equal, class _Alloc>
2185template <class _Key>
2186typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
2187__hash_table<_Tp, _Hash, _Equal, _Alloc>::__erase_unique(const _Key& __k)
2188{
2189    iterator __i = find(__k);
2190    if (__i == end())
2191        return 0;
2192    erase(__i);
2193    return 1;
2194}
2195
2196template <class _Tp, class _Hash, class _Equal, class _Alloc>
2197template <class _Key>
2198typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
2199__hash_table<_Tp, _Hash, _Equal, _Alloc>::__erase_multi(const _Key& __k)
2200{
2201    size_type __r = 0;
2202    iterator __i = find(__k);
2203    if (__i != end())
2204    {
2205        iterator __e = end();
2206        do
2207        {
2208            erase(__i++);
2209            ++__r;
2210        } while (__i != __e && key_eq()(*__i, __k));
2211    }
2212    return __r;
2213}
2214
2215template <class _Tp, class _Hash, class _Equal, class _Alloc>
2216typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_holder
2217__hash_table<_Tp, _Hash, _Equal, _Alloc>::remove(const_iterator __p) _NOEXCEPT
2218{
2219    // current node
2220    __node_pointer __cn = __p.__node_;
2221    size_type __bc = bucket_count();
2222    size_t __chash = __constrain_hash(__cn->__hash_, __bc);
2223    // find previous node
2224    __node_pointer __pn = __bucket_list_[__chash];
2225    for (; __pn->__next_ != __cn; __pn = __pn->__next_)
2226        ;
2227    // Fix up __bucket_list_
2228        // if __pn is not in same bucket (before begin is not in same bucket) &&
2229        //    if __cn->__next_ is not in same bucket (nullptr is not in same bucket)
2230    if (__pn == static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()))
2231                            || __constrain_hash(__pn->__hash_, __bc) != __chash)
2232    {
2233        if (__cn->__next_ == nullptr || __constrain_hash(__cn->__next_->__hash_, __bc) != __chash)
2234            __bucket_list_[__chash] = nullptr;
2235    }
2236        // if __cn->__next_ is not in same bucket (nullptr is in same bucket)
2237    if (__cn->__next_ != nullptr)
2238    {
2239        size_t __nhash = __constrain_hash(__cn->__next_->__hash_, __bc);
2240        if (__nhash != __chash)
2241            __bucket_list_[__nhash] = __pn;
2242    }
2243    // remove __cn
2244    __pn->__next_ = __cn->__next_;
2245    __cn->__next_ = nullptr;
2246    --size();
2247#if _LIBCPP_DEBUG_LEVEL >= 2
2248    __c_node* __c = __get_db()->__find_c_and_lock(this);
2249    for (__i_node** __p = __c->end_; __p != __c->beg_; )
2250    {
2251        --__p;
2252        iterator* __i = static_cast<iterator*>((*__p)->__i_);
2253        if (__i->__node_ == __cn)
2254        {
2255            (*__p)->__c_ = nullptr;
2256            if (--__c->end_ != __p)
2257                memmove(__p, __p+1, (__c->end_ - __p)*sizeof(__i_node*));
2258        }
2259    }
2260    __get_db()->unlock();
2261#endif
2262    return __node_holder(__cn, _Dp(__node_alloc(), true));
2263}
2264
2265template <class _Tp, class _Hash, class _Equal, class _Alloc>
2266template <class _Key>
2267inline _LIBCPP_INLINE_VISIBILITY
2268typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
2269__hash_table<_Tp, _Hash, _Equal, _Alloc>::__count_unique(const _Key& __k) const
2270{
2271    return static_cast<size_type>(find(__k) != end());
2272}
2273
2274template <class _Tp, class _Hash, class _Equal, class _Alloc>
2275template <class _Key>
2276typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
2277__hash_table<_Tp, _Hash, _Equal, _Alloc>::__count_multi(const _Key& __k) const
2278{
2279    size_type __r = 0;
2280    const_iterator __i = find(__k);
2281    if (__i != end())
2282    {
2283        const_iterator __e = end();
2284        do
2285        {
2286            ++__i;
2287            ++__r;
2288        } while (__i != __e && key_eq()(*__i, __k));
2289    }
2290    return __r;
2291}
2292
2293template <class _Tp, class _Hash, class _Equal, class _Alloc>
2294template <class _Key>
2295pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator,
2296     typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator>
2297__hash_table<_Tp, _Hash, _Equal, _Alloc>::__equal_range_unique(
2298        const _Key& __k)
2299{
2300    iterator __i = find(__k);
2301    iterator __j = __i;
2302    if (__i != end())
2303        ++__j;
2304    return pair<iterator, iterator>(__i, __j);
2305}
2306
2307template <class _Tp, class _Hash, class _Equal, class _Alloc>
2308template <class _Key>
2309pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator,
2310     typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator>
2311__hash_table<_Tp, _Hash, _Equal, _Alloc>::__equal_range_unique(
2312        const _Key& __k) const
2313{
2314    const_iterator __i = find(__k);
2315    const_iterator __j = __i;
2316    if (__i != end())
2317        ++__j;
2318    return pair<const_iterator, const_iterator>(__i, __j);
2319}
2320
2321template <class _Tp, class _Hash, class _Equal, class _Alloc>
2322template <class _Key>
2323pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator,
2324     typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator>
2325__hash_table<_Tp, _Hash, _Equal, _Alloc>::__equal_range_multi(
2326        const _Key& __k)
2327{
2328    iterator __i = find(__k);
2329    iterator __j = __i;
2330    if (__i != end())
2331    {
2332        iterator __e = end();
2333        do
2334        {
2335            ++__j;
2336        } while (__j != __e && key_eq()(*__j, __k));
2337    }
2338    return pair<iterator, iterator>(__i, __j);
2339}
2340
2341template <class _Tp, class _Hash, class _Equal, class _Alloc>
2342template <class _Key>
2343pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator,
2344     typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator>
2345__hash_table<_Tp, _Hash, _Equal, _Alloc>::__equal_range_multi(
2346        const _Key& __k) const
2347{
2348    const_iterator __i = find(__k);
2349    const_iterator __j = __i;
2350    if (__i != end())
2351    {
2352        const_iterator __e = end();
2353        do
2354        {
2355            ++__j;
2356        } while (__j != __e && key_eq()(*__j, __k));
2357    }
2358    return pair<const_iterator, const_iterator>(__i, __j);
2359}
2360
2361template <class _Tp, class _Hash, class _Equal, class _Alloc>
2362void
2363__hash_table<_Tp, _Hash, _Equal, _Alloc>::swap(__hash_table& __u)
2364    _NOEXCEPT_(
2365        (!allocator_traits<__pointer_allocator>::propagate_on_container_swap::value ||
2366         __is_nothrow_swappable<__pointer_allocator>::value) &&
2367        (!__node_traits::propagate_on_container_swap::value ||
2368         __is_nothrow_swappable<__node_allocator>::value) &&
2369        __is_nothrow_swappable<hasher>::value &&
2370        __is_nothrow_swappable<key_equal>::value)
2371{
2372    {
2373    __node_pointer_pointer __npp = __bucket_list_.release();
2374    __bucket_list_.reset(__u.__bucket_list_.release());
2375    __u.__bucket_list_.reset(__npp);
2376    }
2377    _VSTD::swap(__bucket_list_.get_deleter().size(), __u.__bucket_list_.get_deleter().size());
2378    __swap_alloc(__bucket_list_.get_deleter().__alloc(),
2379             __u.__bucket_list_.get_deleter().__alloc());
2380    __swap_alloc(__node_alloc(), __u.__node_alloc());
2381    _VSTD::swap(__p1_.first().__next_, __u.__p1_.first().__next_);
2382    __p2_.swap(__u.__p2_);
2383    __p3_.swap(__u.__p3_);
2384    if (size() > 0)
2385        __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash_, bucket_count())] =
2386            static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
2387    if (__u.size() > 0)
2388        __u.__bucket_list_[__constrain_hash(__u.__p1_.first().__next_->__hash_, __u.bucket_count())] =
2389            static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__u.__p1_.first()));
2390#if _LIBCPP_DEBUG_LEVEL >= 2
2391    __get_db()->swap(this, &__u);
2392#endif
2393}
2394
2395template <class _Tp, class _Hash, class _Equal, class _Alloc>
2396typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
2397__hash_table<_Tp, _Hash, _Equal, _Alloc>::bucket_size(size_type __n) const
2398{
2399    _LIBCPP_ASSERT(__n < bucket_count(),
2400        "unordered container::bucket_size(n) called with n >= bucket_count()");
2401    __node_const_pointer __np = __bucket_list_[__n];
2402    size_type __bc = bucket_count();
2403    size_type __r = 0;
2404    if (__np != nullptr)
2405    {
2406        for (__np = __np->__next_; __np != nullptr &&
2407                                   __constrain_hash(__np->__hash_, __bc) == __n;
2408                                                    __np = __np->__next_, ++__r)
2409            ;
2410    }
2411    return __r;
2412}
2413
2414template <class _Tp, class _Hash, class _Equal, class _Alloc>
2415inline _LIBCPP_INLINE_VISIBILITY
2416void
2417swap(__hash_table<_Tp, _Hash, _Equal, _Alloc>& __x,
2418     __hash_table<_Tp, _Hash, _Equal, _Alloc>& __y)
2419    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
2420{
2421    __x.swap(__y);
2422}
2423
2424#if _LIBCPP_DEBUG_LEVEL >= 2
2425
2426template <class _Tp, class _Hash, class _Equal, class _Alloc>
2427bool
2428__hash_table<_Tp, _Hash, _Equal, _Alloc>::__dereferenceable(const const_iterator* __i) const
2429{
2430    return __i->__node_ != nullptr;
2431}
2432
2433template <class _Tp, class _Hash, class _Equal, class _Alloc>
2434bool
2435__hash_table<_Tp, _Hash, _Equal, _Alloc>::__decrementable(const const_iterator*) const
2436{
2437    return false;
2438}
2439
2440template <class _Tp, class _Hash, class _Equal, class _Alloc>
2441bool
2442__hash_table<_Tp, _Hash, _Equal, _Alloc>::__addable(const const_iterator*, ptrdiff_t) const
2443{
2444    return false;
2445}
2446
2447template <class _Tp, class _Hash, class _Equal, class _Alloc>
2448bool
2449__hash_table<_Tp, _Hash, _Equal, _Alloc>::__subscriptable(const const_iterator*, ptrdiff_t) const
2450{
2451    return false;
2452}
2453
2454#endif  // _LIBCPP_DEBUG_LEVEL >= 2
2455_LIBCPP_END_NAMESPACE_STD
2456
2457#endif  // _LIBCPP__HASH_TABLE
2458