libstdc++
hashtable_policy.h
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1 // Internal policy header for unordered_set and unordered_map -*- C++ -*-
2 
3 // Copyright (C) 2010-2015 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15 
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19 
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24 
25 /** @file bits/hashtable_policy.h
26  * This is an internal header file, included by other library headers.
27  * Do not attempt to use it directly.
28  * @headername{unordered_map,unordered_set}
29  */
30 
31 #ifndef _HASHTABLE_POLICY_H
32 #define _HASHTABLE_POLICY_H 1
33 
34 namespace std _GLIBCXX_VISIBILITY(default)
35 {
36 _GLIBCXX_BEGIN_NAMESPACE_VERSION
37 
38  template<typename _Key, typename _Value, typename _Alloc,
39  typename _ExtractKey, typename _Equal,
40  typename _H1, typename _H2, typename _Hash,
41  typename _RehashPolicy, typename _Traits>
42  class _Hashtable;
43 
44 _GLIBCXX_END_NAMESPACE_VERSION
45 
46 namespace __detail
47 {
48 _GLIBCXX_BEGIN_NAMESPACE_VERSION
49 
50  /**
51  * @defgroup hashtable-detail Base and Implementation Classes
52  * @ingroup unordered_associative_containers
53  * @{
54  */
55  template<typename _Key, typename _Value,
56  typename _ExtractKey, typename _Equal,
57  typename _H1, typename _H2, typename _Hash, typename _Traits>
58  struct _Hashtable_base;
59 
60  // Helper function: return distance(first, last) for forward
61  // iterators, or 0 for input iterators.
62  template<class _Iterator>
63  inline typename std::iterator_traits<_Iterator>::difference_type
64  __distance_fw(_Iterator __first, _Iterator __last,
65  std::input_iterator_tag)
66  { return 0; }
67 
68  template<class _Iterator>
69  inline typename std::iterator_traits<_Iterator>::difference_type
70  __distance_fw(_Iterator __first, _Iterator __last,
71  std::forward_iterator_tag)
72  { return std::distance(__first, __last); }
73 
74  template<class _Iterator>
75  inline typename std::iterator_traits<_Iterator>::difference_type
76  __distance_fw(_Iterator __first, _Iterator __last)
77  {
78  typedef typename std::iterator_traits<_Iterator>::iterator_category _Tag;
79  return __distance_fw(__first, __last, _Tag());
80  }
81 
82  // Helper type used to detect whether the hash functor is noexcept.
83  template <typename _Key, typename _Hash>
84  struct __is_noexcept_hash : std::__bool_constant<
85  noexcept(declval<const _Hash&>()(declval<const _Key&>()))>
86  { };
87 
88  struct _Identity
89  {
90  template<typename _Tp>
91  _Tp&&
92  operator()(_Tp&& __x) const
93  { return std::forward<_Tp>(__x); }
94  };
95 
96  struct _Select1st
97  {
98  template<typename _Tp>
99  auto
100  operator()(_Tp&& __x) const
101  -> decltype(std::get<0>(std::forward<_Tp>(__x)))
102  { return std::get<0>(std::forward<_Tp>(__x)); }
103  };
104 
105  template<typename _NodeAlloc>
106  struct _Hashtable_alloc;
107 
108  // Functor recycling a pool of nodes and using allocation once the pool is
109  // empty.
110  template<typename _NodeAlloc>
111  struct _ReuseOrAllocNode
112  {
113  private:
114  using __node_alloc_type = _NodeAlloc;
115  using __hashtable_alloc = _Hashtable_alloc<__node_alloc_type>;
116  using __value_alloc_type = typename __hashtable_alloc::__value_alloc_type;
117  using __value_alloc_traits =
118  typename __hashtable_alloc::__value_alloc_traits;
119  using __node_alloc_traits =
120  typename __hashtable_alloc::__node_alloc_traits;
121  using __node_type = typename __hashtable_alloc::__node_type;
122 
123  public:
124  _ReuseOrAllocNode(__node_type* __nodes, __hashtable_alloc& __h)
125  : _M_nodes(__nodes), _M_h(__h) { }
126  _ReuseOrAllocNode(const _ReuseOrAllocNode&) = delete;
127 
128  ~_ReuseOrAllocNode()
129  { _M_h._M_deallocate_nodes(_M_nodes); }
130 
131  template<typename _Arg>
132  __node_type*
133  operator()(_Arg&& __arg) const
134  {
135  if (_M_nodes)
136  {
137  __node_type* __node = _M_nodes;
138  _M_nodes = _M_nodes->_M_next();
139  __node->_M_nxt = nullptr;
140  __value_alloc_type __a(_M_h._M_node_allocator());
141  __value_alloc_traits::destroy(__a, __node->_M_valptr());
142  __try
143  {
144  __value_alloc_traits::construct(__a, __node->_M_valptr(),
145  std::forward<_Arg>(__arg));
146  }
147  __catch(...)
148  {
149  __node->~__node_type();
150  __node_alloc_traits::deallocate(_M_h._M_node_allocator(),
151  __node, 1);
152  __throw_exception_again;
153  }
154  return __node;
155  }
156  return _M_h._M_allocate_node(std::forward<_Arg>(__arg));
157  }
158 
159  private:
160  mutable __node_type* _M_nodes;
161  __hashtable_alloc& _M_h;
162  };
163 
164  // Functor similar to the previous one but without any pool of nodes to
165  // recycle.
166  template<typename _NodeAlloc>
167  struct _AllocNode
168  {
169  private:
170  using __hashtable_alloc = _Hashtable_alloc<_NodeAlloc>;
171  using __node_type = typename __hashtable_alloc::__node_type;
172 
173  public:
174  _AllocNode(__hashtable_alloc& __h)
175  : _M_h(__h) { }
176 
177  template<typename _Arg>
178  __node_type*
179  operator()(_Arg&& __arg) const
180  { return _M_h._M_allocate_node(std::forward<_Arg>(__arg)); }
181 
182  private:
183  __hashtable_alloc& _M_h;
184  };
185 
186  // Auxiliary types used for all instantiations of _Hashtable nodes
187  // and iterators.
188 
189  /**
190  * struct _Hashtable_traits
191  *
192  * Important traits for hash tables.
193  *
194  * @tparam _Cache_hash_code Boolean value. True if the value of
195  * the hash function is stored along with the value. This is a
196  * time-space tradeoff. Storing it may improve lookup speed by
197  * reducing the number of times we need to call the _Equal
198  * function.
199  *
200  * @tparam _Constant_iterators Boolean value. True if iterator and
201  * const_iterator are both constant iterator types. This is true
202  * for unordered_set and unordered_multiset, false for
203  * unordered_map and unordered_multimap.
204  *
205  * @tparam _Unique_keys Boolean value. True if the return value
206  * of _Hashtable::count(k) is always at most one, false if it may
207  * be an arbitrary number. This is true for unordered_set and
208  * unordered_map, false for unordered_multiset and
209  * unordered_multimap.
210  */
211  template<bool _Cache_hash_code, bool _Constant_iterators, bool _Unique_keys>
212  struct _Hashtable_traits
213  {
214  using __hash_cached = __bool_constant<_Cache_hash_code>;
215  using __constant_iterators = __bool_constant<_Constant_iterators>;
216  using __unique_keys = __bool_constant<_Unique_keys>;
217  };
218 
219  /**
220  * struct _Hash_node_base
221  *
222  * Nodes, used to wrap elements stored in the hash table. A policy
223  * template parameter of class template _Hashtable controls whether
224  * nodes also store a hash code. In some cases (e.g. strings) this
225  * may be a performance win.
226  */
227  struct _Hash_node_base
228  {
229  _Hash_node_base* _M_nxt;
230 
231  _Hash_node_base() noexcept : _M_nxt() { }
232 
233  _Hash_node_base(_Hash_node_base* __next) noexcept : _M_nxt(__next) { }
234  };
235 
236  /**
237  * struct _Hash_node_value_base
238  *
239  * Node type with the value to store.
240  */
241  template<typename _Value>
242  struct _Hash_node_value_base : _Hash_node_base
243  {
244  typedef _Value value_type;
245 
246  __gnu_cxx::__aligned_buffer<_Value> _M_storage;
247 
248  _Value*
249  _M_valptr() noexcept
250  { return _M_storage._M_ptr(); }
251 
252  const _Value*
253  _M_valptr() const noexcept
254  { return _M_storage._M_ptr(); }
255 
256  _Value&
257  _M_v() noexcept
258  { return *_M_valptr(); }
259 
260  const _Value&
261  _M_v() const noexcept
262  { return *_M_valptr(); }
263  };
264 
265  /**
266  * Primary template struct _Hash_node.
267  */
268  template<typename _Value, bool _Cache_hash_code>
269  struct _Hash_node;
270 
271  /**
272  * Specialization for nodes with caches, struct _Hash_node.
273  *
274  * Base class is __detail::_Hash_node_value_base.
275  */
276  template<typename _Value>
277  struct _Hash_node<_Value, true> : _Hash_node_value_base<_Value>
278  {
279  std::size_t _M_hash_code;
280 
281  _Hash_node*
282  _M_next() const noexcept
283  { return static_cast<_Hash_node*>(this->_M_nxt); }
284  };
285 
286  /**
287  * Specialization for nodes without caches, struct _Hash_node.
288  *
289  * Base class is __detail::_Hash_node_value_base.
290  */
291  template<typename _Value>
292  struct _Hash_node<_Value, false> : _Hash_node_value_base<_Value>
293  {
294  _Hash_node*
295  _M_next() const noexcept
296  { return static_cast<_Hash_node*>(this->_M_nxt); }
297  };
298 
299  /// Base class for node iterators.
300  template<typename _Value, bool _Cache_hash_code>
301  struct _Node_iterator_base
302  {
303  using __node_type = _Hash_node<_Value, _Cache_hash_code>;
304 
305  __node_type* _M_cur;
306 
307  _Node_iterator_base(__node_type* __p) noexcept
308  : _M_cur(__p) { }
309 
310  void
311  _M_incr() noexcept
312  { _M_cur = _M_cur->_M_next(); }
313  };
314 
315  template<typename _Value, bool _Cache_hash_code>
316  inline bool
317  operator==(const _Node_iterator_base<_Value, _Cache_hash_code>& __x,
318  const _Node_iterator_base<_Value, _Cache_hash_code >& __y)
319  noexcept
320  { return __x._M_cur == __y._M_cur; }
321 
322  template<typename _Value, bool _Cache_hash_code>
323  inline bool
324  operator!=(const _Node_iterator_base<_Value, _Cache_hash_code>& __x,
325  const _Node_iterator_base<_Value, _Cache_hash_code>& __y)
326  noexcept
327  { return __x._M_cur != __y._M_cur; }
328 
329  /// Node iterators, used to iterate through all the hashtable.
330  template<typename _Value, bool __constant_iterators, bool __cache>
331  struct _Node_iterator
332  : public _Node_iterator_base<_Value, __cache>
333  {
334  private:
335  using __base_type = _Node_iterator_base<_Value, __cache>;
336  using __node_type = typename __base_type::__node_type;
337 
338  public:
339  typedef _Value value_type;
340  typedef std::ptrdiff_t difference_type;
341  typedef std::forward_iterator_tag iterator_category;
342 
343  using pointer = typename std::conditional<__constant_iterators,
344  const _Value*, _Value*>::type;
345 
346  using reference = typename std::conditional<__constant_iterators,
347  const _Value&, _Value&>::type;
348 
349  _Node_iterator() noexcept
350  : __base_type(0) { }
351 
352  explicit
353  _Node_iterator(__node_type* __p) noexcept
354  : __base_type(__p) { }
355 
356  reference
357  operator*() const noexcept
358  { return this->_M_cur->_M_v(); }
359 
360  pointer
361  operator->() const noexcept
362  { return this->_M_cur->_M_valptr(); }
363 
364  _Node_iterator&
365  operator++() noexcept
366  {
367  this->_M_incr();
368  return *this;
369  }
370 
371  _Node_iterator
372  operator++(int) noexcept
373  {
374  _Node_iterator __tmp(*this);
375  this->_M_incr();
376  return __tmp;
377  }
378  };
379 
380  /// Node const_iterators, used to iterate through all the hashtable.
381  template<typename _Value, bool __constant_iterators, bool __cache>
382  struct _Node_const_iterator
383  : public _Node_iterator_base<_Value, __cache>
384  {
385  private:
386  using __base_type = _Node_iterator_base<_Value, __cache>;
387  using __node_type = typename __base_type::__node_type;
388 
389  public:
390  typedef _Value value_type;
391  typedef std::ptrdiff_t difference_type;
392  typedef std::forward_iterator_tag iterator_category;
393 
394  typedef const _Value* pointer;
395  typedef const _Value& reference;
396 
397  _Node_const_iterator() noexcept
398  : __base_type(0) { }
399 
400  explicit
401  _Node_const_iterator(__node_type* __p) noexcept
402  : __base_type(__p) { }
403 
404  _Node_const_iterator(const _Node_iterator<_Value, __constant_iterators,
405  __cache>& __x) noexcept
406  : __base_type(__x._M_cur) { }
407 
408  reference
409  operator*() const noexcept
410  { return this->_M_cur->_M_v(); }
411 
412  pointer
413  operator->() const noexcept
414  { return this->_M_cur->_M_valptr(); }
415 
416  _Node_const_iterator&
417  operator++() noexcept
418  {
419  this->_M_incr();
420  return *this;
421  }
422 
423  _Node_const_iterator
424  operator++(int) noexcept
425  {
426  _Node_const_iterator __tmp(*this);
427  this->_M_incr();
428  return __tmp;
429  }
430  };
431 
432  // Many of class template _Hashtable's template parameters are policy
433  // classes. These are defaults for the policies.
434 
435  /// Default range hashing function: use division to fold a large number
436  /// into the range [0, N).
437  struct _Mod_range_hashing
438  {
439  typedef std::size_t first_argument_type;
440  typedef std::size_t second_argument_type;
441  typedef std::size_t result_type;
442 
443  result_type
444  operator()(first_argument_type __num,
445  second_argument_type __den) const noexcept
446  { return __num % __den; }
447  };
448 
449  /// Default ranged hash function H. In principle it should be a
450  /// function object composed from objects of type H1 and H2 such that
451  /// h(k, N) = h2(h1(k), N), but that would mean making extra copies of
452  /// h1 and h2. So instead we'll just use a tag to tell class template
453  /// hashtable to do that composition.
454  struct _Default_ranged_hash { };
455 
456  /// Default value for rehash policy. Bucket size is (usually) the
457  /// smallest prime that keeps the load factor small enough.
458  struct _Prime_rehash_policy
459  {
460  _Prime_rehash_policy(float __z = 1.0) noexcept
461  : _M_max_load_factor(__z), _M_next_resize(0) { }
462 
463  float
464  max_load_factor() const noexcept
465  { return _M_max_load_factor; }
466 
467  // Return a bucket size no smaller than n.
468  std::size_t
469  _M_next_bkt(std::size_t __n) const;
470 
471  // Return a bucket count appropriate for n elements
472  std::size_t
473  _M_bkt_for_elements(std::size_t __n) const
474  { return __builtin_ceil(__n / (long double)_M_max_load_factor); }
475 
476  // __n_bkt is current bucket count, __n_elt is current element count,
477  // and __n_ins is number of elements to be inserted. Do we need to
478  // increase bucket count? If so, return make_pair(true, n), where n
479  // is the new bucket count. If not, return make_pair(false, 0).
480  std::pair<bool, std::size_t>
481  _M_need_rehash(std::size_t __n_bkt, std::size_t __n_elt,
482  std::size_t __n_ins) const;
483 
484  typedef std::size_t _State;
485 
486  _State
487  _M_state() const
488  { return _M_next_resize; }
489 
490  void
491  _M_reset() noexcept
492  { _M_next_resize = 0; }
493 
494  void
495  _M_reset(_State __state)
496  { _M_next_resize = __state; }
497 
498  enum { _S_n_primes = sizeof(unsigned long) != 8 ? 256 : 256 + 48 };
499 
500  static const std::size_t _S_growth_factor = 2;
501 
502  float _M_max_load_factor;
503  mutable std::size_t _M_next_resize;
504  };
505 
506  // Base classes for std::_Hashtable. We define these base classes
507  // because in some cases we want to do different things depending on
508  // the value of a policy class. In some cases the policy class
509  // affects which member functions and nested typedefs are defined;
510  // we handle that by specializing base class templates. Several of
511  // the base class templates need to access other members of class
512  // template _Hashtable, so we use a variant of the "Curiously
513  // Recurring Template Pattern" (CRTP) technique.
514 
515  /**
516  * Primary class template _Map_base.
517  *
518  * If the hashtable has a value type of the form pair<T1, T2> and a
519  * key extraction policy (_ExtractKey) that returns the first part
520  * of the pair, the hashtable gets a mapped_type typedef. If it
521  * satisfies those criteria and also has unique keys, then it also
522  * gets an operator[].
523  */
524  template<typename _Key, typename _Value, typename _Alloc,
525  typename _ExtractKey, typename _Equal,
526  typename _H1, typename _H2, typename _Hash,
527  typename _RehashPolicy, typename _Traits,
528  bool _Unique_keys = _Traits::__unique_keys::value>
529  struct _Map_base { };
530 
531  /// Partial specialization, __unique_keys set to false.
532  template<typename _Key, typename _Pair, typename _Alloc, typename _Equal,
533  typename _H1, typename _H2, typename _Hash,
534  typename _RehashPolicy, typename _Traits>
535  struct _Map_base<_Key, _Pair, _Alloc, _Select1st, _Equal,
536  _H1, _H2, _Hash, _RehashPolicy, _Traits, false>
537  {
538  using mapped_type = typename std::tuple_element<1, _Pair>::type;
539  };
540 
541  /// Partial specialization, __unique_keys set to true.
542  template<typename _Key, typename _Pair, typename _Alloc, typename _Equal,
543  typename _H1, typename _H2, typename _Hash,
544  typename _RehashPolicy, typename _Traits>
545  struct _Map_base<_Key, _Pair, _Alloc, _Select1st, _Equal,
546  _H1, _H2, _Hash, _RehashPolicy, _Traits, true>
547  {
548  private:
549  using __hashtable_base = __detail::_Hashtable_base<_Key, _Pair,
550  _Select1st,
551  _Equal, _H1, _H2, _Hash,
552  _Traits>;
553 
554  using __hashtable = _Hashtable<_Key, _Pair, _Alloc,
555  _Select1st, _Equal,
556  _H1, _H2, _Hash, _RehashPolicy, _Traits>;
557 
558  using __hash_code = typename __hashtable_base::__hash_code;
559  using __node_type = typename __hashtable_base::__node_type;
560 
561  public:
562  using key_type = typename __hashtable_base::key_type;
563  using iterator = typename __hashtable_base::iterator;
564  using mapped_type = typename std::tuple_element<1, _Pair>::type;
565 
566  mapped_type&
567  operator[](const key_type& __k);
568 
569  mapped_type&
570  operator[](key_type&& __k);
571 
572  // _GLIBCXX_RESOLVE_LIB_DEFECTS
573  // DR 761. unordered_map needs an at() member function.
574  mapped_type&
575  at(const key_type& __k);
576 
577  const mapped_type&
578  at(const key_type& __k) const;
579  };
580 
581  template<typename _Key, typename _Pair, typename _Alloc, typename _Equal,
582  typename _H1, typename _H2, typename _Hash,
583  typename _RehashPolicy, typename _Traits>
584  auto
585  _Map_base<_Key, _Pair, _Alloc, _Select1st, _Equal,
586  _H1, _H2, _Hash, _RehashPolicy, _Traits, true>::
587  operator[](const key_type& __k)
588  -> mapped_type&
589  {
590  __hashtable* __h = static_cast<__hashtable*>(this);
591  __hash_code __code = __h->_M_hash_code(__k);
592  std::size_t __n = __h->_M_bucket_index(__k, __code);
593  __node_type* __p = __h->_M_find_node(__n, __k, __code);
594 
595  if (!__p)
596  {
597  __p = __h->_M_allocate_node(std::piecewise_construct,
598  std::tuple<const key_type&>(__k),
599  std::tuple<>());
600  return __h->_M_insert_unique_node(__n, __code, __p)->second;
601  }
602 
603  return __p->_M_v().second;
604  }
605 
606  template<typename _Key, typename _Pair, typename _Alloc, typename _Equal,
607  typename _H1, typename _H2, typename _Hash,
608  typename _RehashPolicy, typename _Traits>
609  auto
610  _Map_base<_Key, _Pair, _Alloc, _Select1st, _Equal,
611  _H1, _H2, _Hash, _RehashPolicy, _Traits, true>::
612  operator[](key_type&& __k)
613  -> mapped_type&
614  {
615  __hashtable* __h = static_cast<__hashtable*>(this);
616  __hash_code __code = __h->_M_hash_code(__k);
617  std::size_t __n = __h->_M_bucket_index(__k, __code);
618  __node_type* __p = __h->_M_find_node(__n, __k, __code);
619 
620  if (!__p)
621  {
622  __p = __h->_M_allocate_node(std::piecewise_construct,
623  std::forward_as_tuple(std::move(__k)),
624  std::tuple<>());
625  return __h->_M_insert_unique_node(__n, __code, __p)->second;
626  }
627 
628  return __p->_M_v().second;
629  }
630 
631  template<typename _Key, typename _Pair, typename _Alloc, typename _Equal,
632  typename _H1, typename _H2, typename _Hash,
633  typename _RehashPolicy, typename _Traits>
634  auto
635  _Map_base<_Key, _Pair, _Alloc, _Select1st, _Equal,
636  _H1, _H2, _Hash, _RehashPolicy, _Traits, true>::
637  at(const key_type& __k)
638  -> mapped_type&
639  {
640  __hashtable* __h = static_cast<__hashtable*>(this);
641  __hash_code __code = __h->_M_hash_code(__k);
642  std::size_t __n = __h->_M_bucket_index(__k, __code);
643  __node_type* __p = __h->_M_find_node(__n, __k, __code);
644 
645  if (!__p)
646  __throw_out_of_range(__N("_Map_base::at"));
647  return __p->_M_v().second;
648  }
649 
650  template<typename _Key, typename _Pair, typename _Alloc, typename _Equal,
651  typename _H1, typename _H2, typename _Hash,
652  typename _RehashPolicy, typename _Traits>
653  auto
654  _Map_base<_Key, _Pair, _Alloc, _Select1st, _Equal,
655  _H1, _H2, _Hash, _RehashPolicy, _Traits, true>::
656  at(const key_type& __k) const
657  -> const mapped_type&
658  {
659  const __hashtable* __h = static_cast<const __hashtable*>(this);
660  __hash_code __code = __h->_M_hash_code(__k);
661  std::size_t __n = __h->_M_bucket_index(__k, __code);
662  __node_type* __p = __h->_M_find_node(__n, __k, __code);
663 
664  if (!__p)
665  __throw_out_of_range(__N("_Map_base::at"));
666  return __p->_M_v().second;
667  }
668 
669  /**
670  * Primary class template _Insert_base.
671  *
672  * insert member functions appropriate to all _Hashtables.
673  */
674  template<typename _Key, typename _Value, typename _Alloc,
675  typename _ExtractKey, typename _Equal,
676  typename _H1, typename _H2, typename _Hash,
677  typename _RehashPolicy, typename _Traits>
678  struct _Insert_base
679  {
680  protected:
681  using __hashtable = _Hashtable<_Key, _Value, _Alloc, _ExtractKey,
682  _Equal, _H1, _H2, _Hash,
683  _RehashPolicy, _Traits>;
684 
685  using __hashtable_base = _Hashtable_base<_Key, _Value, _ExtractKey,
686  _Equal, _H1, _H2, _Hash,
687  _Traits>;
688 
689  using value_type = typename __hashtable_base::value_type;
690  using iterator = typename __hashtable_base::iterator;
691  using const_iterator = typename __hashtable_base::const_iterator;
692  using size_type = typename __hashtable_base::size_type;
693 
694  using __unique_keys = typename __hashtable_base::__unique_keys;
695  using __ireturn_type = typename __hashtable_base::__ireturn_type;
696  using __node_type = _Hash_node<_Value, _Traits::__hash_cached::value>;
697  using __node_alloc_type = __alloc_rebind<_Alloc, __node_type>;
698  using __node_gen_type = _AllocNode<__node_alloc_type>;
699 
700  __hashtable&
701  _M_conjure_hashtable()
702  { return *(static_cast<__hashtable*>(this)); }
703 
704  template<typename _InputIterator, typename _NodeGetter>
705  void
706  _M_insert_range(_InputIterator __first, _InputIterator __last,
707  const _NodeGetter&);
708 
709  public:
710  __ireturn_type
711  insert(const value_type& __v)
712  {
713  __hashtable& __h = _M_conjure_hashtable();
714  __node_gen_type __node_gen(__h);
715  return __h._M_insert(__v, __node_gen, __unique_keys());
716  }
717 
718  iterator
719  insert(const_iterator __hint, const value_type& __v)
720  {
721  __hashtable& __h = _M_conjure_hashtable();
722  __node_gen_type __node_gen(__h);
723  return __h._M_insert(__hint, __v, __node_gen, __unique_keys());
724  }
725 
726  void
727  insert(initializer_list<value_type> __l)
728  { this->insert(__l.begin(), __l.end()); }
729 
730  template<typename _InputIterator>
731  void
732  insert(_InputIterator __first, _InputIterator __last)
733  {
734  __hashtable& __h = _M_conjure_hashtable();
735  __node_gen_type __node_gen(__h);
736  return _M_insert_range(__first, __last, __node_gen);
737  }
738  };
739 
740  template<typename _Key, typename _Value, typename _Alloc,
741  typename _ExtractKey, typename _Equal,
742  typename _H1, typename _H2, typename _Hash,
743  typename _RehashPolicy, typename _Traits>
744  template<typename _InputIterator, typename _NodeGetter>
745  void
746  _Insert_base<_Key, _Value, _Alloc, _ExtractKey, _Equal, _H1, _H2, _Hash,
747  _RehashPolicy, _Traits>::
748  _M_insert_range(_InputIterator __first, _InputIterator __last,
749  const _NodeGetter& __node_gen)
750  {
751  using __rehash_type = typename __hashtable::__rehash_type;
752  using __rehash_state = typename __hashtable::__rehash_state;
753  using pair_type = std::pair<bool, std::size_t>;
754 
755  size_type __n_elt = __detail::__distance_fw(__first, __last);
756 
757  __hashtable& __h = _M_conjure_hashtable();
758  __rehash_type& __rehash = __h._M_rehash_policy;
759  const __rehash_state& __saved_state = __rehash._M_state();
760  pair_type __do_rehash = __rehash._M_need_rehash(__h._M_bucket_count,
761  __h._M_element_count,
762  __n_elt);
763 
764  if (__do_rehash.first)
765  __h._M_rehash(__do_rehash.second, __saved_state);
766 
767  for (; __first != __last; ++__first)
768  __h._M_insert(*__first, __node_gen, __unique_keys());
769  }
770 
771  /**
772  * Primary class template _Insert.
773  *
774  * Select insert member functions appropriate to _Hashtable policy choices.
775  */
776  template<typename _Key, typename _Value, typename _Alloc,
777  typename _ExtractKey, typename _Equal,
778  typename _H1, typename _H2, typename _Hash,
779  typename _RehashPolicy, typename _Traits,
780  bool _Constant_iterators = _Traits::__constant_iterators::value,
781  bool _Unique_keys = _Traits::__unique_keys::value>
782  struct _Insert;
783 
784  /// Specialization.
785  template<typename _Key, typename _Value, typename _Alloc,
786  typename _ExtractKey, typename _Equal,
787  typename _H1, typename _H2, typename _Hash,
788  typename _RehashPolicy, typename _Traits>
789  struct _Insert<_Key, _Value, _Alloc, _ExtractKey, _Equal, _H1, _H2, _Hash,
790  _RehashPolicy, _Traits, true, true>
791  : public _Insert_base<_Key, _Value, _Alloc, _ExtractKey, _Equal,
792  _H1, _H2, _Hash, _RehashPolicy, _Traits>
793  {
794  using __base_type = _Insert_base<_Key, _Value, _Alloc, _ExtractKey,
795  _Equal, _H1, _H2, _Hash,
796  _RehashPolicy, _Traits>;
797  using value_type = typename __base_type::value_type;
798  using iterator = typename __base_type::iterator;
799  using const_iterator = typename __base_type::const_iterator;
800 
801  using __unique_keys = typename __base_type::__unique_keys;
802  using __hashtable = typename __base_type::__hashtable;
803  using __node_gen_type = typename __base_type::__node_gen_type;
804 
805  using __base_type::insert;
806 
807  std::pair<iterator, bool>
808  insert(value_type&& __v)
809  {
810  __hashtable& __h = this->_M_conjure_hashtable();
811  __node_gen_type __node_gen(__h);
812  return __h._M_insert(std::move(__v), __node_gen, __unique_keys());
813  }
814 
815  iterator
816  insert(const_iterator __hint, value_type&& __v)
817  {
818  __hashtable& __h = this->_M_conjure_hashtable();
819  __node_gen_type __node_gen(__h);
820  return __h._M_insert(__hint, std::move(__v), __node_gen,
821  __unique_keys());
822  }
823  };
824 
825  /// Specialization.
826  template<typename _Key, typename _Value, typename _Alloc,
827  typename _ExtractKey, typename _Equal,
828  typename _H1, typename _H2, typename _Hash,
829  typename _RehashPolicy, typename _Traits>
830  struct _Insert<_Key, _Value, _Alloc, _ExtractKey, _Equal, _H1, _H2, _Hash,
831  _RehashPolicy, _Traits, true, false>
832  : public _Insert_base<_Key, _Value, _Alloc, _ExtractKey, _Equal,
833  _H1, _H2, _Hash, _RehashPolicy, _Traits>
834  {
835  using __base_type = _Insert_base<_Key, _Value, _Alloc, _ExtractKey,
836  _Equal, _H1, _H2, _Hash,
837  _RehashPolicy, _Traits>;
838  using value_type = typename __base_type::value_type;
839  using iterator = typename __base_type::iterator;
840  using const_iterator = typename __base_type::const_iterator;
841 
842  using __unique_keys = typename __base_type::__unique_keys;
843  using __hashtable = typename __base_type::__hashtable;
844  using __node_gen_type = typename __base_type::__node_gen_type;
845 
846  using __base_type::insert;
847 
848  iterator
849  insert(value_type&& __v)
850  {
851  __hashtable& __h = this->_M_conjure_hashtable();
852  __node_gen_type __node_gen(__h);
853  return __h._M_insert(std::move(__v), __node_gen, __unique_keys());
854  }
855 
856  iterator
857  insert(const_iterator __hint, value_type&& __v)
858  {
859  __hashtable& __h = this->_M_conjure_hashtable();
860  __node_gen_type __node_gen(__h);
861  return __h._M_insert(__hint, std::move(__v), __node_gen,
862  __unique_keys());
863  }
864  };
865 
866  /// Specialization.
867  template<typename _Key, typename _Value, typename _Alloc,
868  typename _ExtractKey, typename _Equal,
869  typename _H1, typename _H2, typename _Hash,
870  typename _RehashPolicy, typename _Traits, bool _Unique_keys>
871  struct _Insert<_Key, _Value, _Alloc, _ExtractKey, _Equal, _H1, _H2, _Hash,
872  _RehashPolicy, _Traits, false, _Unique_keys>
873  : public _Insert_base<_Key, _Value, _Alloc, _ExtractKey, _Equal,
874  _H1, _H2, _Hash, _RehashPolicy, _Traits>
875  {
876  using __base_type = _Insert_base<_Key, _Value, _Alloc, _ExtractKey,
877  _Equal, _H1, _H2, _Hash,
878  _RehashPolicy, _Traits>;
879  using value_type = typename __base_type::value_type;
880  using iterator = typename __base_type::iterator;
881  using const_iterator = typename __base_type::const_iterator;
882 
883  using __unique_keys = typename __base_type::__unique_keys;
884  using __hashtable = typename __base_type::__hashtable;
885  using __ireturn_type = typename __base_type::__ireturn_type;
886 
887  using __base_type::insert;
888 
889  template<typename _Pair>
890  using __is_cons = std::is_constructible<value_type, _Pair&&>;
891 
892  template<typename _Pair>
893  using _IFcons = std::enable_if<__is_cons<_Pair>::value>;
894 
895  template<typename _Pair>
896  using _IFconsp = typename _IFcons<_Pair>::type;
897 
898  template<typename _Pair, typename = _IFconsp<_Pair>>
899  __ireturn_type
900  insert(_Pair&& __v)
901  {
902  __hashtable& __h = this->_M_conjure_hashtable();
903  return __h._M_emplace(__unique_keys(), std::forward<_Pair>(__v));
904  }
905 
906  template<typename _Pair, typename = _IFconsp<_Pair>>
907  iterator
908  insert(const_iterator __hint, _Pair&& __v)
909  {
910  __hashtable& __h = this->_M_conjure_hashtable();
911  return __h._M_emplace(__hint, __unique_keys(),
912  std::forward<_Pair>(__v));
913  }
914  };
915 
916  /**
917  * Primary class template _Rehash_base.
918  *
919  * Give hashtable the max_load_factor functions and reserve iff the
920  * rehash policy is _Prime_rehash_policy.
921  */
922  template<typename _Key, typename _Value, typename _Alloc,
923  typename _ExtractKey, typename _Equal,
924  typename _H1, typename _H2, typename _Hash,
925  typename _RehashPolicy, typename _Traits>
926  struct _Rehash_base;
927 
928  /// Specialization.
929  template<typename _Key, typename _Value, typename _Alloc,
930  typename _ExtractKey, typename _Equal,
931  typename _H1, typename _H2, typename _Hash, typename _Traits>
932  struct _Rehash_base<_Key, _Value, _Alloc, _ExtractKey, _Equal,
933  _H1, _H2, _Hash, _Prime_rehash_policy, _Traits>
934  {
935  using __hashtable = _Hashtable<_Key, _Value, _Alloc, _ExtractKey,
936  _Equal, _H1, _H2, _Hash,
937  _Prime_rehash_policy, _Traits>;
938 
939  float
940  max_load_factor() const noexcept
941  {
942  const __hashtable* __this = static_cast<const __hashtable*>(this);
943  return __this->__rehash_policy().max_load_factor();
944  }
945 
946  void
947  max_load_factor(float __z)
948  {
949  __hashtable* __this = static_cast<__hashtable*>(this);
950  __this->__rehash_policy(_Prime_rehash_policy(__z));
951  }
952 
953  void
954  reserve(std::size_t __n)
955  {
956  __hashtable* __this = static_cast<__hashtable*>(this);
957  __this->rehash(__builtin_ceil(__n / max_load_factor()));
958  }
959  };
960 
961  /**
962  * Primary class template _Hashtable_ebo_helper.
963  *
964  * Helper class using EBO when it is not forbidden (the type is not
965  * final) and when it is worth it (the type is empty.)
966  */
967  template<int _Nm, typename _Tp,
968  bool __use_ebo = !__is_final(_Tp) && __is_empty(_Tp)>
969  struct _Hashtable_ebo_helper;
970 
971  /// Specialization using EBO.
972  template<int _Nm, typename _Tp>
973  struct _Hashtable_ebo_helper<_Nm, _Tp, true>
974  : private _Tp
975  {
976  _Hashtable_ebo_helper() = default;
977 
978  template<typename _OtherTp>
979  _Hashtable_ebo_helper(_OtherTp&& __tp)
980  : _Tp(std::forward<_OtherTp>(__tp))
981  { }
982 
983  static const _Tp&
984  _S_cget(const _Hashtable_ebo_helper& __eboh)
985  { return static_cast<const _Tp&>(__eboh); }
986 
987  static _Tp&
988  _S_get(_Hashtable_ebo_helper& __eboh)
989  { return static_cast<_Tp&>(__eboh); }
990  };
991 
992  /// Specialization not using EBO.
993  template<int _Nm, typename _Tp>
994  struct _Hashtable_ebo_helper<_Nm, _Tp, false>
995  {
996  _Hashtable_ebo_helper() = default;
997 
998  template<typename _OtherTp>
999  _Hashtable_ebo_helper(_OtherTp&& __tp)
1000  : _M_tp(std::forward<_OtherTp>(__tp))
1001  { }
1002 
1003  static const _Tp&
1004  _S_cget(const _Hashtable_ebo_helper& __eboh)
1005  { return __eboh._M_tp; }
1006 
1007  static _Tp&
1008  _S_get(_Hashtable_ebo_helper& __eboh)
1009  { return __eboh._M_tp; }
1010 
1011  private:
1012  _Tp _M_tp;
1013  };
1014 
1015  /**
1016  * Primary class template _Local_iterator_base.
1017  *
1018  * Base class for local iterators, used to iterate within a bucket
1019  * but not between buckets.
1020  */
1021  template<typename _Key, typename _Value, typename _ExtractKey,
1022  typename _H1, typename _H2, typename _Hash,
1023  bool __cache_hash_code>
1024  struct _Local_iterator_base;
1025 
1026  /**
1027  * Primary class template _Hash_code_base.
1028  *
1029  * Encapsulates two policy issues that aren't quite orthogonal.
1030  * (1) the difference between using a ranged hash function and using
1031  * the combination of a hash function and a range-hashing function.
1032  * In the former case we don't have such things as hash codes, so
1033  * we have a dummy type as placeholder.
1034  * (2) Whether or not we cache hash codes. Caching hash codes is
1035  * meaningless if we have a ranged hash function.
1036  *
1037  * We also put the key extraction objects here, for convenience.
1038  * Each specialization derives from one or more of the template
1039  * parameters to benefit from Ebo. This is important as this type
1040  * is inherited in some cases by the _Local_iterator_base type used
1041  * to implement local_iterator and const_local_iterator. As with
1042  * any iterator type we prefer to make it as small as possible.
1043  *
1044  * Primary template is unused except as a hook for specializations.
1045  */
1046  template<typename _Key, typename _Value, typename _ExtractKey,
1047  typename _H1, typename _H2, typename _Hash,
1048  bool __cache_hash_code>
1049  struct _Hash_code_base;
1050 
1051  /// Specialization: ranged hash function, no caching hash codes. H1
1052  /// and H2 are provided but ignored. We define a dummy hash code type.
1053  template<typename _Key, typename _Value, typename _ExtractKey,
1054  typename _H1, typename _H2, typename _Hash>
1055  struct _Hash_code_base<_Key, _Value, _ExtractKey, _H1, _H2, _Hash, false>
1056  : private _Hashtable_ebo_helper<0, _ExtractKey>,
1057  private _Hashtable_ebo_helper<1, _Hash>
1058  {
1059  private:
1060  using __ebo_extract_key = _Hashtable_ebo_helper<0, _ExtractKey>;
1061  using __ebo_hash = _Hashtable_ebo_helper<1, _Hash>;
1062 
1063  protected:
1064  typedef void* __hash_code;
1065  typedef _Hash_node<_Value, false> __node_type;
1066 
1067  // We need the default constructor for the local iterators and _Hashtable
1068  // default constructor.
1069  _Hash_code_base() = default;
1070 
1071  _Hash_code_base(const _ExtractKey& __ex, const _H1&, const _H2&,
1072  const _Hash& __h)
1073  : __ebo_extract_key(__ex), __ebo_hash(__h) { }
1074 
1075  __hash_code
1076  _M_hash_code(const _Key& __key) const
1077  { return 0; }
1078 
1079  std::size_t
1080  _M_bucket_index(const _Key& __k, __hash_code, std::size_t __n) const
1081  { return _M_ranged_hash()(__k, __n); }
1082 
1083  std::size_t
1084  _M_bucket_index(const __node_type* __p, std::size_t __n) const
1085  noexcept( noexcept(declval<const _Hash&>()(declval<const _Key&>(),
1086  (std::size_t)0)) )
1087  { return _M_ranged_hash()(_M_extract()(__p->_M_v()), __n); }
1088 
1089  void
1090  _M_store_code(__node_type*, __hash_code) const
1091  { }
1092 
1093  void
1094  _M_copy_code(__node_type*, const __node_type*) const
1095  { }
1096 
1097  void
1098  _M_swap(_Hash_code_base& __x)
1099  {
1100  std::swap(_M_extract(), __x._M_extract());
1101  std::swap(_M_ranged_hash(), __x._M_ranged_hash());
1102  }
1103 
1104  const _ExtractKey&
1105  _M_extract() const { return __ebo_extract_key::_S_cget(*this); }
1106 
1107  _ExtractKey&
1108  _M_extract() { return __ebo_extract_key::_S_get(*this); }
1109 
1110  const _Hash&
1111  _M_ranged_hash() const { return __ebo_hash::_S_cget(*this); }
1112 
1113  _Hash&
1114  _M_ranged_hash() { return __ebo_hash::_S_get(*this); }
1115  };
1116 
1117  // No specialization for ranged hash function while caching hash codes.
1118  // That combination is meaningless, and trying to do it is an error.
1119 
1120  /// Specialization: ranged hash function, cache hash codes. This
1121  /// combination is meaningless, so we provide only a declaration
1122  /// and no definition.
1123  template<typename _Key, typename _Value, typename _ExtractKey,
1124  typename _H1, typename _H2, typename _Hash>
1125  struct _Hash_code_base<_Key, _Value, _ExtractKey, _H1, _H2, _Hash, true>;
1126 
1127  /// Specialization: hash function and range-hashing function, no
1128  /// caching of hash codes.
1129  /// Provides typedef and accessor required by C++ 11.
1130  template<typename _Key, typename _Value, typename _ExtractKey,
1131  typename _H1, typename _H2>
1132  struct _Hash_code_base<_Key, _Value, _ExtractKey, _H1, _H2,
1133  _Default_ranged_hash, false>
1134  : private _Hashtable_ebo_helper<0, _ExtractKey>,
1135  private _Hashtable_ebo_helper<1, _H1>,
1136  private _Hashtable_ebo_helper<2, _H2>
1137  {
1138  private:
1139  using __ebo_extract_key = _Hashtable_ebo_helper<0, _ExtractKey>;
1140  using __ebo_h1 = _Hashtable_ebo_helper<1, _H1>;
1141  using __ebo_h2 = _Hashtable_ebo_helper<2, _H2>;
1142 
1143  // Gives the local iterator implementation access to _M_bucket_index().
1144  friend struct _Local_iterator_base<_Key, _Value, _ExtractKey, _H1, _H2,
1145  _Default_ranged_hash, false>;
1146 
1147  public:
1148  typedef _H1 hasher;
1149 
1150  hasher
1151  hash_function() const
1152  { return _M_h1(); }
1153 
1154  protected:
1155  typedef std::size_t __hash_code;
1156  typedef _Hash_node<_Value, false> __node_type;
1157 
1158  // We need the default constructor for the local iterators and _Hashtable
1159  // default constructor.
1160  _Hash_code_base() = default;
1161 
1162  _Hash_code_base(const _ExtractKey& __ex,
1163  const _H1& __h1, const _H2& __h2,
1164  const _Default_ranged_hash&)
1165  : __ebo_extract_key(__ex), __ebo_h1(__h1), __ebo_h2(__h2) { }
1166 
1167  __hash_code
1168  _M_hash_code(const _Key& __k) const
1169  { return _M_h1()(__k); }
1170 
1171  std::size_t
1172  _M_bucket_index(const _Key&, __hash_code __c, std::size_t __n) const
1173  { return _M_h2()(__c, __n); }
1174 
1175  std::size_t
1176  _M_bucket_index(const __node_type* __p, std::size_t __n) const
1177  noexcept( noexcept(declval<const _H1&>()(declval<const _Key&>()))
1178  && noexcept(declval<const _H2&>()((__hash_code)0,
1179  (std::size_t)0)) )
1180  { return _M_h2()(_M_h1()(_M_extract()(__p->_M_v())), __n); }
1181 
1182  void
1183  _M_store_code(__node_type*, __hash_code) const
1184  { }
1185 
1186  void
1187  _M_copy_code(__node_type*, const __node_type*) const
1188  { }
1189 
1190  void
1191  _M_swap(_Hash_code_base& __x)
1192  {
1193  std::swap(_M_extract(), __x._M_extract());
1194  std::swap(_M_h1(), __x._M_h1());
1195  std::swap(_M_h2(), __x._M_h2());
1196  }
1197 
1198  const _ExtractKey&
1199  _M_extract() const { return __ebo_extract_key::_S_cget(*this); }
1200 
1201  _ExtractKey&
1202  _M_extract() { return __ebo_extract_key::_S_get(*this); }
1203 
1204  const _H1&
1205  _M_h1() const { return __ebo_h1::_S_cget(*this); }
1206 
1207  _H1&
1208  _M_h1() { return __ebo_h1::_S_get(*this); }
1209 
1210  const _H2&
1211  _M_h2() const { return __ebo_h2::_S_cget(*this); }
1212 
1213  _H2&
1214  _M_h2() { return __ebo_h2::_S_get(*this); }
1215  };
1216 
1217  /// Specialization: hash function and range-hashing function,
1218  /// caching hash codes. H is provided but ignored. Provides
1219  /// typedef and accessor required by C++ 11.
1220  template<typename _Key, typename _Value, typename _ExtractKey,
1221  typename _H1, typename _H2>
1222  struct _Hash_code_base<_Key, _Value, _ExtractKey, _H1, _H2,
1223  _Default_ranged_hash, true>
1224  : private _Hashtable_ebo_helper<0, _ExtractKey>,
1225  private _Hashtable_ebo_helper<1, _H1>,
1226  private _Hashtable_ebo_helper<2, _H2>
1227  {
1228  private:
1229  // Gives the local iterator implementation access to _M_h2().
1230  friend struct _Local_iterator_base<_Key, _Value, _ExtractKey, _H1, _H2,
1231  _Default_ranged_hash, true>;
1232 
1233  using __ebo_extract_key = _Hashtable_ebo_helper<0, _ExtractKey>;
1234  using __ebo_h1 = _Hashtable_ebo_helper<1, _H1>;
1235  using __ebo_h2 = _Hashtable_ebo_helper<2, _H2>;
1236 
1237  public:
1238  typedef _H1 hasher;
1239 
1240  hasher
1241  hash_function() const
1242  { return _M_h1(); }
1243 
1244  protected:
1245  typedef std::size_t __hash_code;
1246  typedef _Hash_node<_Value, true> __node_type;
1247 
1248  // We need the default constructor for _Hashtable default constructor.
1249  _Hash_code_base() = default;
1250  _Hash_code_base(const _ExtractKey& __ex,
1251  const _H1& __h1, const _H2& __h2,
1252  const _Default_ranged_hash&)
1253  : __ebo_extract_key(__ex), __ebo_h1(__h1), __ebo_h2(__h2) { }
1254 
1255  __hash_code
1256  _M_hash_code(const _Key& __k) const
1257  { return _M_h1()(__k); }
1258 
1259  std::size_t
1260  _M_bucket_index(const _Key&, __hash_code __c,
1261  std::size_t __n) const
1262  { return _M_h2()(__c, __n); }
1263 
1264  std::size_t
1265  _M_bucket_index(const __node_type* __p, std::size_t __n) const
1266  noexcept( noexcept(declval<const _H2&>()((__hash_code)0,
1267  (std::size_t)0)) )
1268  { return _M_h2()(__p->_M_hash_code, __n); }
1269 
1270  void
1271  _M_store_code(__node_type* __n, __hash_code __c) const
1272  { __n->_M_hash_code = __c; }
1273 
1274  void
1275  _M_copy_code(__node_type* __to, const __node_type* __from) const
1276  { __to->_M_hash_code = __from->_M_hash_code; }
1277 
1278  void
1279  _M_swap(_Hash_code_base& __x)
1280  {
1281  std::swap(_M_extract(), __x._M_extract());
1282  std::swap(_M_h1(), __x._M_h1());
1283  std::swap(_M_h2(), __x._M_h2());
1284  }
1285 
1286  const _ExtractKey&
1287  _M_extract() const { return __ebo_extract_key::_S_cget(*this); }
1288 
1289  _ExtractKey&
1290  _M_extract() { return __ebo_extract_key::_S_get(*this); }
1291 
1292  const _H1&
1293  _M_h1() const { return __ebo_h1::_S_cget(*this); }
1294 
1295  _H1&
1296  _M_h1() { return __ebo_h1::_S_get(*this); }
1297 
1298  const _H2&
1299  _M_h2() const { return __ebo_h2::_S_cget(*this); }
1300 
1301  _H2&
1302  _M_h2() { return __ebo_h2::_S_get(*this); }
1303  };
1304 
1305  /**
1306  * Primary class template _Equal_helper.
1307  *
1308  */
1309  template <typename _Key, typename _Value, typename _ExtractKey,
1310  typename _Equal, typename _HashCodeType,
1311  bool __cache_hash_code>
1312  struct _Equal_helper;
1313 
1314  /// Specialization.
1315  template<typename _Key, typename _Value, typename _ExtractKey,
1316  typename _Equal, typename _HashCodeType>
1317  struct _Equal_helper<_Key, _Value, _ExtractKey, _Equal, _HashCodeType, true>
1318  {
1319  static bool
1320  _S_equals(const _Equal& __eq, const _ExtractKey& __extract,
1321  const _Key& __k, _HashCodeType __c, _Hash_node<_Value, true>* __n)
1322  { return __c == __n->_M_hash_code && __eq(__k, __extract(__n->_M_v())); }
1323  };
1324 
1325  /// Specialization.
1326  template<typename _Key, typename _Value, typename _ExtractKey,
1327  typename _Equal, typename _HashCodeType>
1328  struct _Equal_helper<_Key, _Value, _ExtractKey, _Equal, _HashCodeType, false>
1329  {
1330  static bool
1331  _S_equals(const _Equal& __eq, const _ExtractKey& __extract,
1332  const _Key& __k, _HashCodeType, _Hash_node<_Value, false>* __n)
1333  { return __eq(__k, __extract(__n->_M_v())); }
1334  };
1335 
1336 
1337  /// Partial specialization used when nodes contain a cached hash code.
1338  template<typename _Key, typename _Value, typename _ExtractKey,
1339  typename _H1, typename _H2, typename _Hash>
1340  struct _Local_iterator_base<_Key, _Value, _ExtractKey,
1341  _H1, _H2, _Hash, true>
1342  : private _Hashtable_ebo_helper<0, _H2>
1343  {
1344  protected:
1345  using __base_type = _Hashtable_ebo_helper<0, _H2>;
1346  using __hash_code_base = _Hash_code_base<_Key, _Value, _ExtractKey,
1347  _H1, _H2, _Hash, true>;
1348 
1349  _Local_iterator_base() = default;
1350  _Local_iterator_base(const __hash_code_base& __base,
1351  _Hash_node<_Value, true>* __p,
1352  std::size_t __bkt, std::size_t __bkt_count)
1353  : __base_type(__base._M_h2()),
1354  _M_cur(__p), _M_bucket(__bkt), _M_bucket_count(__bkt_count) { }
1355 
1356  void
1357  _M_incr()
1358  {
1359  _M_cur = _M_cur->_M_next();
1360  if (_M_cur)
1361  {
1362  std::size_t __bkt
1363  = __base_type::_S_get(*this)(_M_cur->_M_hash_code,
1364  _M_bucket_count);
1365  if (__bkt != _M_bucket)
1366  _M_cur = nullptr;
1367  }
1368  }
1369 
1370  _Hash_node<_Value, true>* _M_cur;
1371  std::size_t _M_bucket;
1372  std::size_t _M_bucket_count;
1373 
1374  public:
1375  const void*
1376  _M_curr() const { return _M_cur; } // for equality ops
1377 
1378  std::size_t
1379  _M_get_bucket() const { return _M_bucket; } // for debug mode
1380  };
1381 
1382  // Uninitialized storage for a _Hash_code_base.
1383  // This type is DefaultConstructible and Assignable even if the
1384  // _Hash_code_base type isn't, so that _Local_iterator_base<..., false>
1385  // can be DefaultConstructible and Assignable.
1386  template<typename _Tp, bool _IsEmpty = std::is_empty<_Tp>::value>
1387  struct _Hash_code_storage
1388  {
1389  __gnu_cxx::__aligned_buffer<_Tp> _M_storage;
1390 
1391  _Tp*
1392  _M_h() { return _M_storage._M_ptr(); }
1393 
1394  const _Tp*
1395  _M_h() const { return _M_storage._M_ptr(); }
1396  };
1397 
1398  // Empty partial specialization for empty _Hash_code_base types.
1399  template<typename _Tp>
1400  struct _Hash_code_storage<_Tp, true>
1401  {
1402  static_assert( std::is_empty<_Tp>::value, "Type must be empty" );
1403 
1404  // As _Tp is an empty type there will be no bytes written/read through
1405  // the cast pointer, so no strict-aliasing violation.
1406  _Tp*
1407  _M_h() { return reinterpret_cast<_Tp*>(this); }
1408 
1409  const _Tp*
1410  _M_h() const { return reinterpret_cast<const _Tp*>(this); }
1411  };
1412 
1413  template<typename _Key, typename _Value, typename _ExtractKey,
1414  typename _H1, typename _H2, typename _Hash>
1415  using __hash_code_for_local_iter
1416  = _Hash_code_storage<_Hash_code_base<_Key, _Value, _ExtractKey,
1417  _H1, _H2, _Hash, false>>;
1418 
1419  // Partial specialization used when hash codes are not cached
1420  template<typename _Key, typename _Value, typename _ExtractKey,
1421  typename _H1, typename _H2, typename _Hash>
1422  struct _Local_iterator_base<_Key, _Value, _ExtractKey,
1423  _H1, _H2, _Hash, false>
1424  : __hash_code_for_local_iter<_Key, _Value, _ExtractKey, _H1, _H2, _Hash>
1425  {
1426  protected:
1427  using __hash_code_base = _Hash_code_base<_Key, _Value, _ExtractKey,
1428  _H1, _H2, _Hash, false>;
1429 
1430  _Local_iterator_base() : _M_bucket_count(-1) { }
1431 
1432  _Local_iterator_base(const __hash_code_base& __base,
1433  _Hash_node<_Value, false>* __p,
1434  std::size_t __bkt, std::size_t __bkt_count)
1435  : _M_cur(__p), _M_bucket(__bkt), _M_bucket_count(__bkt_count)
1436  { _M_init(__base); }
1437 
1438  ~_Local_iterator_base()
1439  {
1440  if (_M_bucket_count != -1)
1441  _M_destroy();
1442  }
1443 
1444  _Local_iterator_base(const _Local_iterator_base& __iter)
1445  : _M_cur(__iter._M_cur), _M_bucket(__iter._M_bucket),
1446  _M_bucket_count(__iter._M_bucket_count)
1447  {
1448  if (_M_bucket_count != -1)
1449  _M_init(*__iter._M_h());
1450  }
1451 
1452  _Local_iterator_base&
1453  operator=(const _Local_iterator_base& __iter)
1454  {
1455  if (_M_bucket_count != -1)
1456  _M_destroy();
1457  _M_cur = __iter._M_cur;
1458  _M_bucket = __iter._M_bucket;
1459  _M_bucket_count = __iter._M_bucket_count;
1460  if (_M_bucket_count != -1)
1461  _M_init(*__iter._M_h());
1462  return *this;
1463  }
1464 
1465  void
1466  _M_incr()
1467  {
1468  _M_cur = _M_cur->_M_next();
1469  if (_M_cur)
1470  {
1471  std::size_t __bkt = this->_M_h()->_M_bucket_index(_M_cur,
1472  _M_bucket_count);
1473  if (__bkt != _M_bucket)
1474  _M_cur = nullptr;
1475  }
1476  }
1477 
1478  _Hash_node<_Value, false>* _M_cur;
1479  std::size_t _M_bucket;
1480  std::size_t _M_bucket_count;
1481 
1482  void
1483  _M_init(const __hash_code_base& __base)
1484  { ::new(this->_M_h()) __hash_code_base(__base); }
1485 
1486  void
1487  _M_destroy() { this->_M_h()->~__hash_code_base(); }
1488 
1489  public:
1490  const void*
1491  _M_curr() const { return _M_cur; } // for equality ops and debug mode
1492 
1493  std::size_t
1494  _M_get_bucket() const { return _M_bucket; } // for debug mode
1495  };
1496 
1497  template<typename _Key, typename _Value, typename _ExtractKey,
1498  typename _H1, typename _H2, typename _Hash, bool __cache>
1499  inline bool
1500  operator==(const _Local_iterator_base<_Key, _Value, _ExtractKey,
1501  _H1, _H2, _Hash, __cache>& __x,
1502  const _Local_iterator_base<_Key, _Value, _ExtractKey,
1503  _H1, _H2, _Hash, __cache>& __y)
1504  { return __x._M_curr() == __y._M_curr(); }
1505 
1506  template<typename _Key, typename _Value, typename _ExtractKey,
1507  typename _H1, typename _H2, typename _Hash, bool __cache>
1508  inline bool
1509  operator!=(const _Local_iterator_base<_Key, _Value, _ExtractKey,
1510  _H1, _H2, _Hash, __cache>& __x,
1511  const _Local_iterator_base<_Key, _Value, _ExtractKey,
1512  _H1, _H2, _Hash, __cache>& __y)
1513  { return __x._M_curr() != __y._M_curr(); }
1514 
1515  /// local iterators
1516  template<typename _Key, typename _Value, typename _ExtractKey,
1517  typename _H1, typename _H2, typename _Hash,
1518  bool __constant_iterators, bool __cache>
1519  struct _Local_iterator
1520  : public _Local_iterator_base<_Key, _Value, _ExtractKey,
1521  _H1, _H2, _Hash, __cache>
1522  {
1523  private:
1524  using __base_type = _Local_iterator_base<_Key, _Value, _ExtractKey,
1525  _H1, _H2, _Hash, __cache>;
1526  using __hash_code_base = typename __base_type::__hash_code_base;
1527  public:
1528  typedef _Value value_type;
1529  typedef typename std::conditional<__constant_iterators,
1530  const _Value*, _Value*>::type
1531  pointer;
1532  typedef typename std::conditional<__constant_iterators,
1533  const _Value&, _Value&>::type
1534  reference;
1535  typedef std::ptrdiff_t difference_type;
1536  typedef std::forward_iterator_tag iterator_category;
1537 
1538  _Local_iterator() = default;
1539 
1540  _Local_iterator(const __hash_code_base& __base,
1541  _Hash_node<_Value, __cache>* __p,
1542  std::size_t __bkt, std::size_t __bkt_count)
1543  : __base_type(__base, __p, __bkt, __bkt_count)
1544  { }
1545 
1546  reference
1547  operator*() const
1548  { return this->_M_cur->_M_v(); }
1549 
1550  pointer
1551  operator->() const
1552  { return this->_M_cur->_M_valptr(); }
1553 
1554  _Local_iterator&
1555  operator++()
1556  {
1557  this->_M_incr();
1558  return *this;
1559  }
1560 
1561  _Local_iterator
1562  operator++(int)
1563  {
1564  _Local_iterator __tmp(*this);
1565  this->_M_incr();
1566  return __tmp;
1567  }
1568  };
1569 
1570  /// local const_iterators
1571  template<typename _Key, typename _Value, typename _ExtractKey,
1572  typename _H1, typename _H2, typename _Hash,
1573  bool __constant_iterators, bool __cache>
1574  struct _Local_const_iterator
1575  : public _Local_iterator_base<_Key, _Value, _ExtractKey,
1576  _H1, _H2, _Hash, __cache>
1577  {
1578  private:
1579  using __base_type = _Local_iterator_base<_Key, _Value, _ExtractKey,
1580  _H1, _H2, _Hash, __cache>;
1581  using __hash_code_base = typename __base_type::__hash_code_base;
1582 
1583  public:
1584  typedef _Value value_type;
1585  typedef const _Value* pointer;
1586  typedef const _Value& reference;
1587  typedef std::ptrdiff_t difference_type;
1588  typedef std::forward_iterator_tag iterator_category;
1589 
1590  _Local_const_iterator() = default;
1591 
1592  _Local_const_iterator(const __hash_code_base& __base,
1593  _Hash_node<_Value, __cache>* __p,
1594  std::size_t __bkt, std::size_t __bkt_count)
1595  : __base_type(__base, __p, __bkt, __bkt_count)
1596  { }
1597 
1598  _Local_const_iterator(const _Local_iterator<_Key, _Value, _ExtractKey,
1599  _H1, _H2, _Hash,
1600  __constant_iterators,
1601  __cache>& __x)
1602  : __base_type(__x)
1603  { }
1604 
1605  reference
1606  operator*() const
1607  { return this->_M_cur->_M_v(); }
1608 
1609  pointer
1610  operator->() const
1611  { return this->_M_cur->_M_valptr(); }
1612 
1613  _Local_const_iterator&
1614  operator++()
1615  {
1616  this->_M_incr();
1617  return *this;
1618  }
1619 
1620  _Local_const_iterator
1621  operator++(int)
1622  {
1623  _Local_const_iterator __tmp(*this);
1624  this->_M_incr();
1625  return __tmp;
1626  }
1627  };
1628 
1629  /**
1630  * Primary class template _Hashtable_base.
1631  *
1632  * Helper class adding management of _Equal functor to
1633  * _Hash_code_base type.
1634  *
1635  * Base class templates are:
1636  * - __detail::_Hash_code_base
1637  * - __detail::_Hashtable_ebo_helper
1638  */
1639  template<typename _Key, typename _Value,
1640  typename _ExtractKey, typename _Equal,
1641  typename _H1, typename _H2, typename _Hash, typename _Traits>
1642  struct _Hashtable_base
1643  : public _Hash_code_base<_Key, _Value, _ExtractKey, _H1, _H2, _Hash,
1644  _Traits::__hash_cached::value>,
1645  private _Hashtable_ebo_helper<0, _Equal>
1646  {
1647  public:
1648  typedef _Key key_type;
1649  typedef _Value value_type;
1650  typedef _Equal key_equal;
1651  typedef std::size_t size_type;
1652  typedef std::ptrdiff_t difference_type;
1653 
1654  using __traits_type = _Traits;
1655  using __hash_cached = typename __traits_type::__hash_cached;
1656  using __constant_iterators = typename __traits_type::__constant_iterators;
1657  using __unique_keys = typename __traits_type::__unique_keys;
1658 
1659  using __hash_code_base = _Hash_code_base<_Key, _Value, _ExtractKey,
1660  _H1, _H2, _Hash,
1661  __hash_cached::value>;
1662 
1663  using __hash_code = typename __hash_code_base::__hash_code;
1664  using __node_type = typename __hash_code_base::__node_type;
1665 
1666  using iterator = __detail::_Node_iterator<value_type,
1667  __constant_iterators::value,
1668  __hash_cached::value>;
1669 
1670  using const_iterator = __detail::_Node_const_iterator<value_type,
1671  __constant_iterators::value,
1672  __hash_cached::value>;
1673 
1674  using local_iterator = __detail::_Local_iterator<key_type, value_type,
1675  _ExtractKey, _H1, _H2, _Hash,
1676  __constant_iterators::value,
1677  __hash_cached::value>;
1678 
1679  using const_local_iterator = __detail::_Local_const_iterator<key_type,
1680  value_type,
1681  _ExtractKey, _H1, _H2, _Hash,
1682  __constant_iterators::value,
1683  __hash_cached::value>;
1684 
1685  using __ireturn_type = typename std::conditional<__unique_keys::value,
1686  std::pair<iterator, bool>,
1687  iterator>::type;
1688  private:
1689  using _EqualEBO = _Hashtable_ebo_helper<0, _Equal>;
1690  using _EqualHelper = _Equal_helper<_Key, _Value, _ExtractKey, _Equal,
1691  __hash_code, __hash_cached::value>;
1692 
1693  protected:
1694  _Hashtable_base() = default;
1695  _Hashtable_base(const _ExtractKey& __ex, const _H1& __h1, const _H2& __h2,
1696  const _Hash& __hash, const _Equal& __eq)
1697  : __hash_code_base(__ex, __h1, __h2, __hash), _EqualEBO(__eq)
1698  { }
1699 
1700  bool
1701  _M_equals(const _Key& __k, __hash_code __c, __node_type* __n) const
1702  {
1703  return _EqualHelper::_S_equals(_M_eq(), this->_M_extract(),
1704  __k, __c, __n);
1705  }
1706 
1707  void
1708  _M_swap(_Hashtable_base& __x)
1709  {
1710  __hash_code_base::_M_swap(__x);
1711  std::swap(_M_eq(), __x._M_eq());
1712  }
1713 
1714  const _Equal&
1715  _M_eq() const { return _EqualEBO::_S_cget(*this); }
1716 
1717  _Equal&
1718  _M_eq() { return _EqualEBO::_S_get(*this); }
1719  };
1720 
1721  /**
1722  * struct _Equality_base.
1723  *
1724  * Common types and functions for class _Equality.
1725  */
1726  struct _Equality_base
1727  {
1728  protected:
1729  template<typename _Uiterator>
1730  static bool
1731  _S_is_permutation(_Uiterator, _Uiterator, _Uiterator);
1732  };
1733 
1734  // See std::is_permutation in N3068.
1735  template<typename _Uiterator>
1736  bool
1737  _Equality_base::
1738  _S_is_permutation(_Uiterator __first1, _Uiterator __last1,
1739  _Uiterator __first2)
1740  {
1741  for (; __first1 != __last1; ++__first1, ++__first2)
1742  if (!(*__first1 == *__first2))
1743  break;
1744 
1745  if (__first1 == __last1)
1746  return true;
1747 
1748  _Uiterator __last2 = __first2;
1749  std::advance(__last2, std::distance(__first1, __last1));
1750 
1751  for (_Uiterator __it1 = __first1; __it1 != __last1; ++__it1)
1752  {
1753  _Uiterator __tmp = __first1;
1754  while (__tmp != __it1 && !bool(*__tmp == *__it1))
1755  ++__tmp;
1756 
1757  // We've seen this one before.
1758  if (__tmp != __it1)
1759  continue;
1760 
1761  std::ptrdiff_t __n2 = 0;
1762  for (__tmp = __first2; __tmp != __last2; ++__tmp)
1763  if (*__tmp == *__it1)
1764  ++__n2;
1765 
1766  if (!__n2)
1767  return false;
1768 
1769  std::ptrdiff_t __n1 = 0;
1770  for (__tmp = __it1; __tmp != __last1; ++__tmp)
1771  if (*__tmp == *__it1)
1772  ++__n1;
1773 
1774  if (__n1 != __n2)
1775  return false;
1776  }
1777  return true;
1778  }
1779 
1780  /**
1781  * Primary class template _Equality.
1782  *
1783  * This is for implementing equality comparison for unordered
1784  * containers, per N3068, by John Lakos and Pablo Halpern.
1785  * Algorithmically, we follow closely the reference implementations
1786  * therein.
1787  */
1788  template<typename _Key, typename _Value, typename _Alloc,
1789  typename _ExtractKey, typename _Equal,
1790  typename _H1, typename _H2, typename _Hash,
1791  typename _RehashPolicy, typename _Traits,
1792  bool _Unique_keys = _Traits::__unique_keys::value>
1793  struct _Equality;
1794 
1795  /// Specialization.
1796  template<typename _Key, typename _Value, typename _Alloc,
1797  typename _ExtractKey, typename _Equal,
1798  typename _H1, typename _H2, typename _Hash,
1799  typename _RehashPolicy, typename _Traits>
1800  struct _Equality<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1801  _H1, _H2, _Hash, _RehashPolicy, _Traits, true>
1802  {
1803  using __hashtable = _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1804  _H1, _H2, _Hash, _RehashPolicy, _Traits>;
1805 
1806  bool
1807  _M_equal(const __hashtable&) const;
1808  };
1809 
1810  template<typename _Key, typename _Value, typename _Alloc,
1811  typename _ExtractKey, typename _Equal,
1812  typename _H1, typename _H2, typename _Hash,
1813  typename _RehashPolicy, typename _Traits>
1814  bool
1815  _Equality<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1816  _H1, _H2, _Hash, _RehashPolicy, _Traits, true>::
1817  _M_equal(const __hashtable& __other) const
1818  {
1819  const __hashtable* __this = static_cast<const __hashtable*>(this);
1820 
1821  if (__this->size() != __other.size())
1822  return false;
1823 
1824  for (auto __itx = __this->begin(); __itx != __this->end(); ++__itx)
1825  {
1826  const auto __ity = __other.find(_ExtractKey()(*__itx));
1827  if (__ity == __other.end() || !bool(*__ity == *__itx))
1828  return false;
1829  }
1830  return true;
1831  }
1832 
1833  /// Specialization.
1834  template<typename _Key, typename _Value, typename _Alloc,
1835  typename _ExtractKey, typename _Equal,
1836  typename _H1, typename _H2, typename _Hash,
1837  typename _RehashPolicy, typename _Traits>
1838  struct _Equality<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1839  _H1, _H2, _Hash, _RehashPolicy, _Traits, false>
1840  : public _Equality_base
1841  {
1842  using __hashtable = _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1843  _H1, _H2, _Hash, _RehashPolicy, _Traits>;
1844 
1845  bool
1846  _M_equal(const __hashtable&) const;
1847  };
1848 
1849  template<typename _Key, typename _Value, typename _Alloc,
1850  typename _ExtractKey, typename _Equal,
1851  typename _H1, typename _H2, typename _Hash,
1852  typename _RehashPolicy, typename _Traits>
1853  bool
1854  _Equality<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1855  _H1, _H2, _Hash, _RehashPolicy, _Traits, false>::
1856  _M_equal(const __hashtable& __other) const
1857  {
1858  const __hashtable* __this = static_cast<const __hashtable*>(this);
1859 
1860  if (__this->size() != __other.size())
1861  return false;
1862 
1863  for (auto __itx = __this->begin(); __itx != __this->end();)
1864  {
1865  const auto __xrange = __this->equal_range(_ExtractKey()(*__itx));
1866  const auto __yrange = __other.equal_range(_ExtractKey()(*__itx));
1867 
1868  if (std::distance(__xrange.first, __xrange.second)
1869  != std::distance(__yrange.first, __yrange.second))
1870  return false;
1871 
1872  if (!_S_is_permutation(__xrange.first, __xrange.second,
1873  __yrange.first))
1874  return false;
1875 
1876  __itx = __xrange.second;
1877  }
1878  return true;
1879  }
1880 
1881  /**
1882  * This type deals with all allocation and keeps an allocator instance through
1883  * inheritance to benefit from EBO when possible.
1884  */
1885  template<typename _NodeAlloc>
1886  struct _Hashtable_alloc : private _Hashtable_ebo_helper<0, _NodeAlloc>
1887  {
1888  private:
1889  using __ebo_node_alloc = _Hashtable_ebo_helper<0, _NodeAlloc>;
1890  public:
1891  using __node_type = typename _NodeAlloc::value_type;
1892  using __node_alloc_type = _NodeAlloc;
1893  // Use __gnu_cxx to benefit from _S_always_equal and al.
1894  using __node_alloc_traits = __gnu_cxx::__alloc_traits<__node_alloc_type>;
1895 
1896  using __value_type = typename __node_type::value_type;
1897  using __value_alloc_type =
1898  __alloc_rebind<__node_alloc_type, __value_type>;
1899  using __value_alloc_traits = std::allocator_traits<__value_alloc_type>;
1900 
1901  using __node_base = __detail::_Hash_node_base;
1902  using __bucket_type = __node_base*;
1903  using __bucket_alloc_type =
1904  __alloc_rebind<__node_alloc_type, __bucket_type>;
1905  using __bucket_alloc_traits = std::allocator_traits<__bucket_alloc_type>;
1906 
1907  _Hashtable_alloc() = default;
1908  _Hashtable_alloc(const _Hashtable_alloc&) = default;
1909  _Hashtable_alloc(_Hashtable_alloc&&) = default;
1910 
1911  template<typename _Alloc>
1912  _Hashtable_alloc(_Alloc&& __a)
1913  : __ebo_node_alloc(std::forward<_Alloc>(__a))
1914  { }
1915 
1916  __node_alloc_type&
1917  _M_node_allocator()
1918  { return __ebo_node_alloc::_S_get(*this); }
1919 
1920  const __node_alloc_type&
1921  _M_node_allocator() const
1922  { return __ebo_node_alloc::_S_cget(*this); }
1923 
1924  template<typename... _Args>
1925  __node_type*
1926  _M_allocate_node(_Args&&... __args);
1927 
1928  void
1929  _M_deallocate_node(__node_type* __n);
1930 
1931  // Deallocate the linked list of nodes pointed to by __n
1932  void
1933  _M_deallocate_nodes(__node_type* __n);
1934 
1935  __bucket_type*
1936  _M_allocate_buckets(std::size_t __n);
1937 
1938  void
1939  _M_deallocate_buckets(__bucket_type*, std::size_t __n);
1940  };
1941 
1942  // Definitions of class template _Hashtable_alloc's out-of-line member
1943  // functions.
1944  template<typename _NodeAlloc>
1945  template<typename... _Args>
1946  typename _Hashtable_alloc<_NodeAlloc>::__node_type*
1947  _Hashtable_alloc<_NodeAlloc>::_M_allocate_node(_Args&&... __args)
1948  {
1949  auto __nptr = __node_alloc_traits::allocate(_M_node_allocator(), 1);
1950  __node_type* __n = std::__addressof(*__nptr);
1951  __try
1952  {
1953  __value_alloc_type __a(_M_node_allocator());
1954  ::new ((void*)__n) __node_type;
1955  __value_alloc_traits::construct(__a, __n->_M_valptr(),
1956  std::forward<_Args>(__args)...);
1957  return __n;
1958  }
1959  __catch(...)
1960  {
1961  __node_alloc_traits::deallocate(_M_node_allocator(), __nptr, 1);
1962  __throw_exception_again;
1963  }
1964  }
1965 
1966  template<typename _NodeAlloc>
1967  void
1968  _Hashtable_alloc<_NodeAlloc>::_M_deallocate_node(__node_type* __n)
1969  {
1970  typedef typename __node_alloc_traits::pointer _Ptr;
1971  auto __ptr = std::pointer_traits<_Ptr>::pointer_to(*__n);
1972  __value_alloc_type __a(_M_node_allocator());
1973  __value_alloc_traits::destroy(__a, __n->_M_valptr());
1974  __n->~__node_type();
1975  __node_alloc_traits::deallocate(_M_node_allocator(), __ptr, 1);
1976  }
1977 
1978  template<typename _NodeAlloc>
1979  void
1980  _Hashtable_alloc<_NodeAlloc>::_M_deallocate_nodes(__node_type* __n)
1981  {
1982  while (__n)
1983  {
1984  __node_type* __tmp = __n;
1985  __n = __n->_M_next();
1986  _M_deallocate_node(__tmp);
1987  }
1988  }
1989 
1990  template<typename _NodeAlloc>
1991  typename _Hashtable_alloc<_NodeAlloc>::__bucket_type*
1992  _Hashtable_alloc<_NodeAlloc>::_M_allocate_buckets(std::size_t __n)
1993  {
1994  __bucket_alloc_type __alloc(_M_node_allocator());
1995 
1996  auto __ptr = __bucket_alloc_traits::allocate(__alloc, __n);
1997  __bucket_type* __p = std::__addressof(*__ptr);
1998  __builtin_memset(__p, 0, __n * sizeof(__bucket_type));
1999  return __p;
2000  }
2001 
2002  template<typename _NodeAlloc>
2003  void
2004  _Hashtable_alloc<_NodeAlloc>::_M_deallocate_buckets(__bucket_type* __bkts,
2005  std::size_t __n)
2006  {
2007  typedef typename __bucket_alloc_traits::pointer _Ptr;
2008  auto __ptr = std::pointer_traits<_Ptr>::pointer_to(*__bkts);
2009  __bucket_alloc_type __alloc(_M_node_allocator());
2010  __bucket_alloc_traits::deallocate(__alloc, __ptr, __n);
2011  }
2012 
2013  //@} hashtable-detail
2014 _GLIBCXX_END_NAMESPACE_VERSION
2015 } // namespace __detail
2016 } // namespace std
2017 
2018 #endif // _HASHTABLE_POLICY_H
std::advance
void advance(_InputIterator &__i, _Distance __n)
A generalization of pointer arithmetic.
Definition: stl_iterator_base_funcs.h:173
std::tuple
Primary class template, tuple.
Definition: tuple:463
std::allocator_traits
Uniform interface to all allocator types.
Definition: bits/alloc_traits.h:83
std::input_iterator_tag
Marking input iterators.
Definition: stl_iterator_base_types.h:89
std::__addressof
_Tp * __addressof(_Tp &__r) noexcept
Same as C++11 std::addressof.
Definition: move.h:47
std::piecewise_construct
constexpr piecewise_construct_t piecewise_construct
piecewise_construct
Definition: stl_pair.h:79
std::__detail::_Default_ranged_hash
Default ranged hash function H. In principle it should be a function object composed from objects of ...
Definition: hashtable_policy.h:454
std::operator*
complex< _Tp > operator*(const complex< _Tp > &__x, const complex< _Tp > &__y)
Return new complex value x times y.
Definition: complex:386
std::forward
constexpr _Tp && forward(typename std::remove_reference< _Tp >::type &__t) noexcept
Forward an lvalue.
Definition: move.h:76
std::distance
iterator_traits< _InputIterator >::difference_type distance(_InputIterator __first, _InputIterator __last)
A generalization of pointer arithmetic.
Definition: stl_iterator_base_funcs.h:114
std::initializer_list
initializer_list
Definition: initializer_list:47
std::is_empty
is_empty
Definition: type_traits:668
std::tuple_element
tuple_element
Definition: array:324
std::__detail::_Node_iterator_base
Base class for node iterators.
Definition: hashtable_policy.h:301
std::__detail::_Prime_rehash_policy
Default value for rehash policy. Bucket size is (usually) the smallest prime that keeps the load fact...
Definition: hashtable_policy.h:458
std::__detail::_Node_const_iterator
Node const_iterators, used to iterate through all the hashtable.
Definition: hashtable_policy.h:382
std::pointer_traits
Uniform interface to all pointer-like types.
Definition: ptr_traits.h:132
std::integral_constant
integral_constant
Definition: type_traits:69
std::__detail::_Node_iterator
Node iterators, used to iterate through all the hashtable.
Definition: hashtable_policy.h:331
__gnu_debug::__base
_Siter_base< _Iterator >::iterator_type __base(_Iterator __it)
Definition: functions.h:558
std::__detail::_Mod_range_hashing
Default range hashing function: use division to fold a large number into the range [0...
Definition: hashtable_policy.h:437
std::pair
Struct holding two objects of arbitrary type.
Definition: stl_pair.h:96
std::forward_iterator_tag
Forward iterators support a superset of input iterator operations.
Definition: stl_iterator_base_types.h:95
std
ISO C++ entities toplevel namespace is std.
__gnu_cxx::__alloc_traits
Uniform interface to C++98 and C++0x allocators.
Definition: ext/alloc_traits.h:95
std::iterator
Common iterator class.
Definition: stl_iterator_base_types.h:118