libstdc++
hashtable_policy.h
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1 // Internal policy header for unordered_set and unordered_map -*- C++ -*-
2 
3 // Copyright (C) 2010-2020 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 #include <tuple> // for std::tuple, std::forward_as_tuple
35 #include <bits/stl_algobase.h> // for std::min, std::is_permutation.
36 #include <ext/numeric_traits.h> // for __gnu_cxx::__int_traits
37 
38 namespace std _GLIBCXX_VISIBILITY(default)
39 {
40 _GLIBCXX_BEGIN_NAMESPACE_VERSION
41 
42  template<typename _Key, typename _Value, typename _Alloc,
43  typename _ExtractKey, typename _Equal,
44  typename _Hash, typename _RangeHash, typename _Unused,
45  typename _RehashPolicy, typename _Traits>
46  class _Hashtable;
47 
48 namespace __detail
49 {
50  /**
51  * @defgroup hashtable-detail Base and Implementation Classes
52  * @ingroup unordered_associative_containers
53  * @{
54  */
55  template<typename _Key, typename _Value, typename _ExtractKey,
56  typename _Equal, typename _Hash, typename _RangeHash,
57  typename _Unused, typename _Traits>
58  struct _Hashtable_base;
59 
60  // Helper function: return distance(first, last) for forward
61  // iterators, or 0/1 for input iterators.
62  template<class _Iterator>
64  __distance_fw(_Iterator __first, _Iterator __last,
66  { return __first != __last ? 1 : 0; }
67 
68  template<class _Iterator>
70  __distance_fw(_Iterator __first, _Iterator __last,
72  { return std::distance(__first, __last); }
73 
74  template<class _Iterator>
76  __distance_fw(_Iterator __first, _Iterator __last)
77  { return __distance_fw(__first, __last,
78  std::__iterator_category(__first)); }
79 
80  struct _Identity
81  {
82  template<typename _Tp>
83  _Tp&&
84  operator()(_Tp&& __x) const noexcept
85  { return std::forward<_Tp>(__x); }
86  };
87 
88  struct _Select1st
89  {
90  template<typename _Tp>
91  auto
92  operator()(_Tp&& __x) const noexcept
93  -> decltype(std::get<0>(std::forward<_Tp>(__x)))
94  { return std::get<0>(std::forward<_Tp>(__x)); }
95  };
96 
97  template<typename _NodeAlloc>
98  struct _Hashtable_alloc;
99 
100  // Functor recycling a pool of nodes and using allocation once the pool is
101  // empty.
102  template<typename _NodeAlloc>
103  struct _ReuseOrAllocNode
104  {
105  private:
106  using __node_alloc_type = _NodeAlloc;
107  using __hashtable_alloc = _Hashtable_alloc<__node_alloc_type>;
108  using __node_alloc_traits =
109  typename __hashtable_alloc::__node_alloc_traits;
110  using __node_type = typename __hashtable_alloc::__node_type;
111 
112  public:
113  _ReuseOrAllocNode(__node_type* __nodes, __hashtable_alloc& __h)
114  : _M_nodes(__nodes), _M_h(__h) { }
115  _ReuseOrAllocNode(const _ReuseOrAllocNode&) = delete;
116 
117  ~_ReuseOrAllocNode()
118  { _M_h._M_deallocate_nodes(_M_nodes); }
119 
120  template<typename _Arg>
121  __node_type*
122  operator()(_Arg&& __arg) const
123  {
124  if (_M_nodes)
125  {
126  __node_type* __node = _M_nodes;
127  _M_nodes = _M_nodes->_M_next();
128  __node->_M_nxt = nullptr;
129  auto& __a = _M_h._M_node_allocator();
130  __node_alloc_traits::destroy(__a, __node->_M_valptr());
131  __try
132  {
133  __node_alloc_traits::construct(__a, __node->_M_valptr(),
134  std::forward<_Arg>(__arg));
135  }
136  __catch(...)
137  {
138  _M_h._M_deallocate_node_ptr(__node);
139  __throw_exception_again;
140  }
141  return __node;
142  }
143  return _M_h._M_allocate_node(std::forward<_Arg>(__arg));
144  }
145 
146  private:
147  mutable __node_type* _M_nodes;
148  __hashtable_alloc& _M_h;
149  };
150 
151  // Functor similar to the previous one but without any pool of nodes to
152  // recycle.
153  template<typename _NodeAlloc>
154  struct _AllocNode
155  {
156  private:
157  using __hashtable_alloc = _Hashtable_alloc<_NodeAlloc>;
158  using __node_type = typename __hashtable_alloc::__node_type;
159 
160  public:
161  _AllocNode(__hashtable_alloc& __h)
162  : _M_h(__h) { }
163 
164  template<typename _Arg>
165  __node_type*
166  operator()(_Arg&& __arg) const
167  { return _M_h._M_allocate_node(std::forward<_Arg>(__arg)); }
168 
169  private:
170  __hashtable_alloc& _M_h;
171  };
172 
173  // Auxiliary types used for all instantiations of _Hashtable nodes
174  // and iterators.
175 
176  /**
177  * struct _Hashtable_traits
178  *
179  * Important traits for hash tables.
180  *
181  * @tparam _Cache_hash_code Boolean value. True if the value of
182  * the hash function is stored along with the value. This is a
183  * time-space tradeoff. Storing it may improve lookup speed by
184  * reducing the number of times we need to call the _Hash or _Equal
185  * functors.
186  *
187  * @tparam _Constant_iterators Boolean value. True if iterator and
188  * const_iterator are both constant iterator types. This is true
189  * for unordered_set and unordered_multiset, false for
190  * unordered_map and unordered_multimap.
191  *
192  * @tparam _Unique_keys Boolean value. True if the return value
193  * of _Hashtable::count(k) is always at most one, false if it may
194  * be an arbitrary number. This is true for unordered_set and
195  * unordered_map, false for unordered_multiset and
196  * unordered_multimap.
197  */
198  template<bool _Cache_hash_code, bool _Constant_iterators, bool _Unique_keys>
200  {
204  };
205 
206  /**
207  * struct _Hash_node_base
208  *
209  * Nodes, used to wrap elements stored in the hash table. A policy
210  * template parameter of class template _Hashtable controls whether
211  * nodes also store a hash code. In some cases (e.g. strings) this
212  * may be a performance win.
213  */
215  {
216  _Hash_node_base* _M_nxt;
217 
218  _Hash_node_base() noexcept : _M_nxt() { }
219 
220  _Hash_node_base(_Hash_node_base* __next) noexcept : _M_nxt(__next) { }
221  };
222 
223  /**
224  * struct _Hash_node_value_base
225  *
226  * Node type with the value to store.
227  */
228  template<typename _Value>
230  {
231  typedef _Value value_type;
232 
233  __gnu_cxx::__aligned_buffer<_Value> _M_storage;
234 
235  _Value*
236  _M_valptr() noexcept
237  { return _M_storage._M_ptr(); }
238 
239  const _Value*
240  _M_valptr() const noexcept
241  { return _M_storage._M_ptr(); }
242 
243  _Value&
244  _M_v() noexcept
245  { return *_M_valptr(); }
246 
247  const _Value&
248  _M_v() const noexcept
249  { return *_M_valptr(); }
250  };
251 
252  /**
253  * Primary template struct _Hash_node_code_cache.
254  */
255  template<bool _Cache_hash_code>
257  { };
258 
259  /**
260  * Specialization for node with cache, struct _Hash_node_code_cache.
261  */
262  template<>
264  { std::size_t _M_hash_code; };
265 
266  template<typename _Value, bool _Cache_hash_code>
267  struct _Hash_node_value
268  : _Hash_node_value_base<_Value>
269  , _Hash_node_code_cache<_Cache_hash_code>
270  { };
271 
272  /**
273  * Primary template struct _Hash_node.
274  */
275  template<typename _Value, bool _Cache_hash_code>
276  struct _Hash_node
278  , _Hash_node_value<_Value, _Cache_hash_code>
279  {
280  _Hash_node*
281  _M_next() const noexcept
282  { return static_cast<_Hash_node*>(this->_M_nxt); }
283  };
284 
285  /// Base class for node iterators.
286  template<typename _Value, bool _Cache_hash_code>
288  {
290 
291  __node_type* _M_cur;
292 
293  _Node_iterator_base() = default;
294  _Node_iterator_base(__node_type* __p) noexcept
295  : _M_cur(__p) { }
296 
297  void
298  _M_incr() noexcept
299  { _M_cur = _M_cur->_M_next(); }
300 
301  friend bool
302  operator==(const _Node_iterator_base& __x, const _Node_iterator_base& __y)
303  noexcept
304  { return __x._M_cur == __y._M_cur; }
305 
306 #if __cpp_impl_three_way_comparison < 201907L
307  friend bool
308  operator!=(const _Node_iterator_base& __x, const _Node_iterator_base& __y)
309  noexcept
310  { return __x._M_cur != __y._M_cur; }
311 #endif
312  };
313 
314  /// Node iterators, used to iterate through all the hashtable.
315  template<typename _Value, bool __constant_iterators, bool __cache>
317  : public _Node_iterator_base<_Value, __cache>
318  {
319  private:
321  using __node_type = typename __base_type::__node_type;
322 
323  public:
324  typedef _Value value_type;
325  typedef std::ptrdiff_t difference_type;
327 
328  using pointer = typename std::conditional<__constant_iterators,
329  const value_type*, value_type*>::type;
330 
331  using reference = typename std::conditional<__constant_iterators,
332  const value_type&, value_type&>::type;
333 
334  _Node_iterator() noexcept
335  : __base_type(nullptr) { }
336 
337  explicit
338  _Node_iterator(__node_type* __p) noexcept
339  : __base_type(__p) { }
340 
341  reference
342  operator*() const noexcept
343  { return this->_M_cur->_M_v(); }
344 
345  pointer
346  operator->() const noexcept
347  { return this->_M_cur->_M_valptr(); }
348 
350  operator++() noexcept
351  {
352  this->_M_incr();
353  return *this;
354  }
355 
357  operator++(int) noexcept
358  {
359  _Node_iterator __tmp(*this);
360  this->_M_incr();
361  return __tmp;
362  }
363  };
364 
365  /// Node const_iterators, used to iterate through all the hashtable.
366  template<typename _Value, bool __constant_iterators, bool __cache>
368  : public _Node_iterator_base<_Value, __cache>
369  {
370  private:
372  using __node_type = typename __base_type::__node_type;
373 
374  public:
375  typedef _Value value_type;
376  typedef std::ptrdiff_t difference_type;
378 
379  typedef const value_type* pointer;
380  typedef const value_type& reference;
381 
382  _Node_const_iterator() noexcept
383  : __base_type(nullptr) { }
384 
385  explicit
386  _Node_const_iterator(__node_type* __p) noexcept
387  : __base_type(__p) { }
388 
389  _Node_const_iterator(const _Node_iterator<_Value, __constant_iterators,
390  __cache>& __x) noexcept
391  : __base_type(__x._M_cur) { }
392 
393  reference
394  operator*() const noexcept
395  { return this->_M_cur->_M_v(); }
396 
397  pointer
398  operator->() const noexcept
399  { return this->_M_cur->_M_valptr(); }
400 
402  operator++() noexcept
403  {
404  this->_M_incr();
405  return *this;
406  }
407 
409  operator++(int) noexcept
410  {
411  _Node_const_iterator __tmp(*this);
412  this->_M_incr();
413  return __tmp;
414  }
415  };
416 
417  // Many of class template _Hashtable's template parameters are policy
418  // classes. These are defaults for the policies.
419 
420  /// Default range hashing function: use division to fold a large number
421  /// into the range [0, N).
423  {
424  typedef std::size_t first_argument_type;
425  typedef std::size_t second_argument_type;
426  typedef std::size_t result_type;
427 
428  result_type
429  operator()(first_argument_type __num,
430  second_argument_type __den) const noexcept
431  { return __num % __den; }
432  };
433 
434  /// Default ranged hash function H. In principle it should be a
435  /// function object composed from objects of type H1 and H2 such that
436  /// h(k, N) = h2(h1(k), N), but that would mean making extra copies of
437  /// h1 and h2. So instead we'll just use a tag to tell class template
438  /// hashtable to do that composition.
440 
441  /// Default value for rehash policy. Bucket size is (usually) the
442  /// smallest prime that keeps the load factor small enough.
444  {
446 
447  _Prime_rehash_policy(float __z = 1.0) noexcept
448  : _M_max_load_factor(__z), _M_next_resize(0) { }
449 
450  float
451  max_load_factor() const noexcept
452  { return _M_max_load_factor; }
453 
454  // Return a bucket size no smaller than n.
455  std::size_t
456  _M_next_bkt(std::size_t __n) const;
457 
458  // Return a bucket count appropriate for n elements
459  std::size_t
460  _M_bkt_for_elements(std::size_t __n) const
461  { return __builtin_ceil(__n / (double)_M_max_load_factor); }
462 
463  // __n_bkt is current bucket count, __n_elt is current element count,
464  // and __n_ins is number of elements to be inserted. Do we need to
465  // increase bucket count? If so, return make_pair(true, n), where n
466  // is the new bucket count. If not, return make_pair(false, 0).
468  _M_need_rehash(std::size_t __n_bkt, std::size_t __n_elt,
469  std::size_t __n_ins) const;
470 
471  typedef std::size_t _State;
472 
473  _State
474  _M_state() const
475  { return _M_next_resize; }
476 
477  void
478  _M_reset() noexcept
479  { _M_next_resize = 0; }
480 
481  void
482  _M_reset(_State __state)
483  { _M_next_resize = __state; }
484 
485  static const std::size_t _S_growth_factor = 2;
486 
487  float _M_max_load_factor;
488  mutable std::size_t _M_next_resize;
489  };
490 
491  /// Range hashing function assuming that second arg is a power of 2.
493  {
494  typedef std::size_t first_argument_type;
495  typedef std::size_t second_argument_type;
496  typedef std::size_t result_type;
497 
498  result_type
499  operator()(first_argument_type __num,
500  second_argument_type __den) const noexcept
501  { return __num & (__den - 1); }
502  };
503 
504  /// Compute closest power of 2 not less than __n
505  inline std::size_t
506  __clp2(std::size_t __n) noexcept
507  {
509  // Equivalent to return __n ? std::bit_ceil(__n) : 0;
510  if (__n < 2)
511  return __n;
512  const unsigned __lz = sizeof(size_t) > sizeof(long)
513  ? __builtin_clzll(__n - 1ull)
514  : __builtin_clzl(__n - 1ul);
515  // Doing two shifts avoids undefined behaviour when __lz == 0.
516  return (size_t(1) << (__int_traits<size_t>::__digits - __lz - 1)) << 1;
517  }
518 
519  /// Rehash policy providing power of 2 bucket numbers. Avoids modulo
520  /// operations.
522  {
524 
525  _Power2_rehash_policy(float __z = 1.0) noexcept
526  : _M_max_load_factor(__z), _M_next_resize(0) { }
527 
528  float
529  max_load_factor() const noexcept
530  { return _M_max_load_factor; }
531 
532  // Return a bucket size no smaller than n (as long as n is not above the
533  // highest power of 2).
534  std::size_t
535  _M_next_bkt(std::size_t __n) noexcept
536  {
537  if (__n == 0)
538  // Special case on container 1st initialization with 0 bucket count
539  // hint. We keep _M_next_resize to 0 to make sure that next time we
540  // want to add an element allocation will take place.
541  return 1;
542 
543  const auto __max_width = std::min<size_t>(sizeof(size_t), 8);
544  const auto __max_bkt = size_t(1) << (__max_width * __CHAR_BIT__ - 1);
545  std::size_t __res = __clp2(__n);
546 
547  if (__res == 0)
548  __res = __max_bkt;
549  else if (__res == 1)
550  // If __res is 1 we force it to 2 to make sure there will be an
551  // allocation so that nothing need to be stored in the initial
552  // single bucket
553  __res = 2;
554 
555  if (__res == __max_bkt)
556  // Set next resize to the max value so that we never try to rehash again
557  // as we already reach the biggest possible bucket number.
558  // Note that it might result in max_load_factor not being respected.
559  _M_next_resize = size_t(-1);
560  else
561  _M_next_resize
562  = __builtin_floor(__res * (double)_M_max_load_factor);
563 
564  return __res;
565  }
566 
567  // Return a bucket count appropriate for n elements
568  std::size_t
569  _M_bkt_for_elements(std::size_t __n) const noexcept
570  { return __builtin_ceil(__n / (double)_M_max_load_factor); }
571 
572  // __n_bkt is current bucket count, __n_elt is current element count,
573  // and __n_ins is number of elements to be inserted. Do we need to
574  // increase bucket count? If so, return make_pair(true, n), where n
575  // is the new bucket count. If not, return make_pair(false, 0).
577  _M_need_rehash(std::size_t __n_bkt, std::size_t __n_elt,
578  std::size_t __n_ins) noexcept
579  {
580  if (__n_elt + __n_ins > _M_next_resize)
581  {
582  // If _M_next_resize is 0 it means that we have nothing allocated so
583  // far and that we start inserting elements. In this case we start
584  // with an initial bucket size of 11.
585  double __min_bkts
586  = std::max<std::size_t>(__n_elt + __n_ins, _M_next_resize ? 0 : 11)
587  / (double)_M_max_load_factor;
588  if (__min_bkts >= __n_bkt)
589  return { true,
590  _M_next_bkt(std::max<std::size_t>(__builtin_floor(__min_bkts) + 1,
591  __n_bkt * _S_growth_factor)) };
592 
593  _M_next_resize
594  = __builtin_floor(__n_bkt * (double)_M_max_load_factor);
595  return { false, 0 };
596  }
597  else
598  return { false, 0 };
599  }
600 
601  typedef std::size_t _State;
602 
603  _State
604  _M_state() const noexcept
605  { return _M_next_resize; }
606 
607  void
608  _M_reset() noexcept
609  { _M_next_resize = 0; }
610 
611  void
612  _M_reset(_State __state) noexcept
613  { _M_next_resize = __state; }
614 
615  static const std::size_t _S_growth_factor = 2;
616 
617  float _M_max_load_factor;
618  std::size_t _M_next_resize;
619  };
620 
621  // Base classes for std::_Hashtable. We define these base classes
622  // because in some cases we want to do different things depending on
623  // the value of a policy class. In some cases the policy class
624  // affects which member functions and nested typedefs are defined;
625  // we handle that by specializing base class templates. Several of
626  // the base class templates need to access other members of class
627  // template _Hashtable, so we use a variant of the "Curiously
628  // Recurring Template Pattern" (CRTP) technique.
629 
630  /**
631  * Primary class template _Map_base.
632  *
633  * If the hashtable has a value type of the form pair<T1, T2> and a
634  * key extraction policy (_ExtractKey) that returns the first part
635  * of the pair, the hashtable gets a mapped_type typedef. If it
636  * satisfies those criteria and also has unique keys, then it also
637  * gets an operator[].
638  */
639  template<typename _Key, typename _Value, typename _Alloc,
640  typename _ExtractKey, typename _Equal,
641  typename _Hash, typename _RangeHash, typename _Unused,
642  typename _RehashPolicy, typename _Traits,
643  bool _Unique_keys = _Traits::__unique_keys::value>
644  struct _Map_base { };
645 
646  /// Partial specialization, __unique_keys set to false.
647  template<typename _Key, typename _Pair, typename _Alloc, typename _Equal,
648  typename _Hash, typename _RangeHash, typename _Unused,
649  typename _RehashPolicy, typename _Traits>
650  struct _Map_base<_Key, _Pair, _Alloc, _Select1st, _Equal,
651  _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits, false>
652  {
653  using mapped_type = typename std::tuple_element<1, _Pair>::type;
654  };
655 
656  /// Partial specialization, __unique_keys set to true.
657  template<typename _Key, typename _Pair, typename _Alloc, typename _Equal,
658  typename _Hash, typename _RangeHash, typename _Unused,
659  typename _RehashPolicy, typename _Traits>
660  struct _Map_base<_Key, _Pair, _Alloc, _Select1st, _Equal,
661  _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits, true>
662  {
663  private:
664  using __hashtable_base = _Hashtable_base<_Key, _Pair, _Select1st, _Equal,
665  _Hash, _RangeHash, _Unused,
666  _Traits>;
667 
668  using __hashtable = _Hashtable<_Key, _Pair, _Alloc, _Select1st, _Equal,
669  _Hash, _RangeHash,
670  _Unused, _RehashPolicy, _Traits>;
671 
672  using __hash_code = typename __hashtable_base::__hash_code;
673 
674  public:
675  using key_type = typename __hashtable_base::key_type;
676  using mapped_type = typename std::tuple_element<1, _Pair>::type;
677 
678  mapped_type&
679  operator[](const key_type& __k);
680 
681  mapped_type&
682  operator[](key_type&& __k);
683 
684  // _GLIBCXX_RESOLVE_LIB_DEFECTS
685  // DR 761. unordered_map needs an at() member function.
686  mapped_type&
687  at(const key_type& __k);
688 
689  const mapped_type&
690  at(const key_type& __k) const;
691  };
692 
693  template<typename _Key, typename _Pair, typename _Alloc, typename _Equal,
694  typename _Hash, typename _RangeHash, typename _Unused,
695  typename _RehashPolicy, typename _Traits>
696  auto
697  _Map_base<_Key, _Pair, _Alloc, _Select1st, _Equal,
698  _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits, true>::
699  operator[](const key_type& __k)
700  -> mapped_type&
701  {
702  __hashtable* __h = static_cast<__hashtable*>(this);
703  __hash_code __code = __h->_M_hash_code(__k);
704  std::size_t __bkt = __h->_M_bucket_index(__code);
705  if (auto __node = __h->_M_find_node(__bkt, __k, __code))
706  return __node->_M_v().second;
707 
708  typename __hashtable::_Scoped_node __node {
709  __h,
712  std::tuple<>()
713  };
714  auto __pos
715  = __h->_M_insert_unique_node(__bkt, __code, __node._M_node);
716  __node._M_node = nullptr;
717  return __pos->second;
718  }
719 
720  template<typename _Key, typename _Pair, typename _Alloc, typename _Equal,
721  typename _Hash, typename _RangeHash, typename _Unused,
722  typename _RehashPolicy, typename _Traits>
723  auto
724  _Map_base<_Key, _Pair, _Alloc, _Select1st, _Equal,
725  _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits, true>::
726  operator[](key_type&& __k)
727  -> mapped_type&
728  {
729  __hashtable* __h = static_cast<__hashtable*>(this);
730  __hash_code __code = __h->_M_hash_code(__k);
731  std::size_t __bkt = __h->_M_bucket_index(__code);
732  if (auto __node = __h->_M_find_node(__bkt, __k, __code))
733  return __node->_M_v().second;
734 
735  typename __hashtable::_Scoped_node __node {
736  __h,
739  std::tuple<>()
740  };
741  auto __pos
742  = __h->_M_insert_unique_node(__bkt, __code, __node._M_node);
743  __node._M_node = nullptr;
744  return __pos->second;
745  }
746 
747  template<typename _Key, typename _Pair, typename _Alloc, typename _Equal,
748  typename _Hash, typename _RangeHash, typename _Unused,
749  typename _RehashPolicy, typename _Traits>
750  auto
751  _Map_base<_Key, _Pair, _Alloc, _Select1st, _Equal,
752  _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits, true>::
753  at(const key_type& __k)
754  -> mapped_type&
755  {
756  __hashtable* __h = static_cast<__hashtable*>(this);
757  auto __ite = __h->find(__k);
758 
759  if (!__ite._M_cur)
760  __throw_out_of_range(__N("_Map_base::at"));
761  return __ite->second;
762  }
763 
764  template<typename _Key, typename _Pair, typename _Alloc, typename _Equal,
765  typename _Hash, typename _RangeHash, typename _Unused,
766  typename _RehashPolicy, typename _Traits>
767  auto
768  _Map_base<_Key, _Pair, _Alloc, _Select1st, _Equal,
769  _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits, true>::
770  at(const key_type& __k) const
771  -> const mapped_type&
772  {
773  const __hashtable* __h = static_cast<const __hashtable*>(this);
774  auto __ite = __h->find(__k);
775 
776  if (!__ite._M_cur)
777  __throw_out_of_range(__N("_Map_base::at"));
778  return __ite->second;
779  }
780 
781  /**
782  * Primary class template _Insert_base.
783  *
784  * Defines @c insert member functions appropriate to all _Hashtables.
785  */
786  template<typename _Key, typename _Value, typename _Alloc,
787  typename _ExtractKey, typename _Equal,
788  typename _Hash, typename _RangeHash, typename _Unused,
789  typename _RehashPolicy, typename _Traits>
791  {
792  protected:
793  using __hashtable_base = _Hashtable_base<_Key, _Value, _ExtractKey,
794  _Equal, _Hash, _RangeHash,
795  _Unused, _Traits>;
796 
797  using __hashtable = _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
798  _Hash, _RangeHash,
799  _Unused, _RehashPolicy, _Traits>;
800 
801  using __hash_cached = typename _Traits::__hash_cached;
802  using __constant_iterators = typename _Traits::__constant_iterators;
803 
805  __alloc_rebind<_Alloc, _Hash_node<_Value,
806  __hash_cached::value>>>;
807 
808  using value_type = typename __hashtable_base::value_type;
809  using size_type = typename __hashtable_base::size_type;
810 
811  using __unique_keys = typename _Traits::__unique_keys;
812  using __node_alloc_type = typename __hashtable_alloc::__node_alloc_type;
813  using __node_gen_type = _AllocNode<__node_alloc_type>;
814 
815  __hashtable&
816  _M_conjure_hashtable()
817  { return *(static_cast<__hashtable*>(this)); }
818 
819  template<typename _InputIterator, typename _NodeGetter>
820  void
821  _M_insert_range(_InputIterator __first, _InputIterator __last,
822  const _NodeGetter&, true_type __uks);
823 
824  template<typename _InputIterator, typename _NodeGetter>
825  void
826  _M_insert_range(_InputIterator __first, _InputIterator __last,
827  const _NodeGetter&, false_type __uks);
828 
829  public:
830  using iterator = _Node_iterator<_Value, __constant_iterators::value,
831  __hash_cached::value>;
832 
833  using const_iterator = _Node_const_iterator<_Value, __constant_iterators::value,
834  __hash_cached::value>;
835 
836  using __ireturn_type = typename std::conditional<__unique_keys::value,
838  iterator>::type;
839 
840  __ireturn_type
841  insert(const value_type& __v)
842  {
843  __hashtable& __h = _M_conjure_hashtable();
844  __node_gen_type __node_gen(__h);
845  return __h._M_insert(__v, __node_gen, __unique_keys{});
846  }
847 
848  iterator
849  insert(const_iterator __hint, const value_type& __v)
850  {
851  __hashtable& __h = _M_conjure_hashtable();
852  __node_gen_type __node_gen(__h);
853  return __h._M_insert(__hint, __v, __node_gen, __unique_keys{});
854  }
855 
856  template<typename _KType, typename... _Args>
858  try_emplace(const_iterator, _KType&& __k, _Args&&... __args)
859  {
860  __hashtable& __h = _M_conjure_hashtable();
861  auto __code = __h._M_hash_code(__k);
862  std::size_t __bkt = __h._M_bucket_index(__code);
863  if (auto __node = __h._M_find_node(__bkt, __k, __code))
864  return { iterator(__node), false };
865 
866  typename __hashtable::_Scoped_node __node {
867  &__h,
869  std::forward_as_tuple(std::forward<_KType>(__k)),
870  std::forward_as_tuple(std::forward<_Args>(__args)...)
871  };
872  auto __it
873  = __h._M_insert_unique_node(__bkt, __code, __node._M_node);
874  __node._M_node = nullptr;
875  return { __it, true };
876  }
877 
878  void
879  insert(initializer_list<value_type> __l)
880  { this->insert(__l.begin(), __l.end()); }
881 
882  template<typename _InputIterator>
883  void
884  insert(_InputIterator __first, _InputIterator __last)
885  {
886  __hashtable& __h = _M_conjure_hashtable();
887  __node_gen_type __node_gen(__h);
888  return _M_insert_range(__first, __last, __node_gen, __unique_keys{});
889  }
890  };
891 
892  template<typename _Key, typename _Value, typename _Alloc,
893  typename _ExtractKey, typename _Equal,
894  typename _Hash, typename _RangeHash, typename _Unused,
895  typename _RehashPolicy, typename _Traits>
896  template<typename _InputIterator, typename _NodeGetter>
897  void
898  _Insert_base<_Key, _Value, _Alloc, _ExtractKey, _Equal,
899  _Hash, _RangeHash, _Unused,
900  _RehashPolicy, _Traits>::
901  _M_insert_range(_InputIterator __first, _InputIterator __last,
902  const _NodeGetter& __node_gen, true_type __uks)
903  {
904  __hashtable& __h = _M_conjure_hashtable();
905  for (; __first != __last; ++__first)
906  __h._M_insert(*__first, __node_gen, __uks);
907  }
908 
909  template<typename _Key, typename _Value, typename _Alloc,
910  typename _ExtractKey, typename _Equal,
911  typename _Hash, typename _RangeHash, typename _Unused,
912  typename _RehashPolicy, typename _Traits>
913  template<typename _InputIterator, typename _NodeGetter>
914  void
915  _Insert_base<_Key, _Value, _Alloc, _ExtractKey, _Equal,
916  _Hash, _RangeHash, _Unused,
917  _RehashPolicy, _Traits>::
918  _M_insert_range(_InputIterator __first, _InputIterator __last,
919  const _NodeGetter& __node_gen, false_type __uks)
920  {
921  using __rehash_type = typename __hashtable::__rehash_type;
922  using __rehash_state = typename __hashtable::__rehash_state;
923  using pair_type = std::pair<bool, std::size_t>;
924 
925  size_type __n_elt = __detail::__distance_fw(__first, __last);
926  if (__n_elt == 0)
927  return;
928 
929  __hashtable& __h = _M_conjure_hashtable();
930  __rehash_type& __rehash = __h._M_rehash_policy;
931  const __rehash_state& __saved_state = __rehash._M_state();
932  pair_type __do_rehash = __rehash._M_need_rehash(__h._M_bucket_count,
933  __h._M_element_count,
934  __n_elt);
935 
936  if (__do_rehash.first)
937  __h._M_rehash(__do_rehash.second, __saved_state);
938 
939  for (; __first != __last; ++__first)
940  __h._M_insert(*__first, __node_gen, __uks);
941  }
942 
943  /**
944  * Primary class template _Insert.
945  *
946  * Defines @c insert member functions that depend on _Hashtable policies,
947  * via partial specializations.
948  */
949  template<typename _Key, typename _Value, typename _Alloc,
950  typename _ExtractKey, typename _Equal,
951  typename _Hash, typename _RangeHash, typename _Unused,
952  typename _RehashPolicy, typename _Traits,
953  bool _Constant_iterators = _Traits::__constant_iterators::value>
954  struct _Insert;
955 
956  /// Specialization.
957  template<typename _Key, typename _Value, typename _Alloc,
958  typename _ExtractKey, typename _Equal,
959  typename _Hash, typename _RangeHash, typename _Unused,
960  typename _RehashPolicy, typename _Traits>
961  struct _Insert<_Key, _Value, _Alloc, _ExtractKey, _Equal,
962  _Hash, _RangeHash, _Unused,
963  _RehashPolicy, _Traits, true>
964  : public _Insert_base<_Key, _Value, _Alloc, _ExtractKey, _Equal,
965  _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits>
966  {
967  using __base_type = _Insert_base<_Key, _Value, _Alloc, _ExtractKey,
968  _Equal, _Hash, _RangeHash, _Unused,
969  _RehashPolicy, _Traits>;
970 
971  using value_type = typename __base_type::value_type;
972  using iterator = typename __base_type::iterator;
973  using const_iterator = typename __base_type::const_iterator;
974  using __ireturn_type = typename __base_type::__ireturn_type;
975 
976  using __unique_keys = typename __base_type::__unique_keys;
977  using __hashtable = typename __base_type::__hashtable;
978  using __node_gen_type = typename __base_type::__node_gen_type;
979 
980  using __base_type::insert;
981 
982  __ireturn_type
983  insert(value_type&& __v)
984  {
985  __hashtable& __h = this->_M_conjure_hashtable();
986  __node_gen_type __node_gen(__h);
987  return __h._M_insert(std::move(__v), __node_gen, __unique_keys{});
988  }
989 
990  iterator
991  insert(const_iterator __hint, value_type&& __v)
992  {
993  __hashtable& __h = this->_M_conjure_hashtable();
994  __node_gen_type __node_gen(__h);
995  return __h._M_insert(__hint, std::move(__v), __node_gen,
996  __unique_keys{});
997  }
998  };
999 
1000  /// Specialization.
1001  template<typename _Key, typename _Value, typename _Alloc,
1002  typename _ExtractKey, typename _Equal,
1003  typename _Hash, typename _RangeHash, typename _Unused,
1004  typename _RehashPolicy, typename _Traits>
1005  struct _Insert<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1006  _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits, false>
1007  : public _Insert_base<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1008  _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits>
1009  {
1010  using __base_type = _Insert_base<_Key, _Value, _Alloc, _ExtractKey,
1011  _Equal, _Hash, _RangeHash, _Unused,
1012  _RehashPolicy, _Traits>;
1013  using value_type = typename __base_type::value_type;
1014  using iterator = typename __base_type::iterator;
1016 
1017  using __unique_keys = typename __base_type::__unique_keys;
1018  using __hashtable = typename __base_type::__hashtable;
1019  using __ireturn_type = typename __base_type::__ireturn_type;
1020 
1021  using __base_type::insert;
1022 
1023  template<typename _Pair>
1025 
1026  template<typename _Pair>
1028 
1029  template<typename _Pair>
1030  using _IFconsp = typename _IFcons<_Pair>::type;
1031 
1032  template<typename _Pair, typename = _IFconsp<_Pair>>
1033  __ireturn_type
1034  insert(_Pair&& __v)
1035  {
1036  __hashtable& __h = this->_M_conjure_hashtable();
1037  return __h._M_emplace(__unique_keys{}, std::forward<_Pair>(__v));
1038  }
1039 
1040  template<typename _Pair, typename = _IFconsp<_Pair>>
1041  iterator
1042  insert(const_iterator __hint, _Pair&& __v)
1043  {
1044  __hashtable& __h = this->_M_conjure_hashtable();
1045  return __h._M_emplace(__hint, __unique_keys{},
1046  std::forward<_Pair>(__v));
1047  }
1048  };
1049 
1050  template<typename _Policy>
1051  using __has_load_factor = typename _Policy::__has_load_factor;
1052 
1053  /**
1054  * Primary class template _Rehash_base.
1055  *
1056  * Give hashtable the max_load_factor functions and reserve iff the
1057  * rehash policy supports it.
1058  */
1059  template<typename _Key, typename _Value, typename _Alloc,
1060  typename _ExtractKey, typename _Equal,
1061  typename _Hash, typename _RangeHash, typename _Unused,
1062  typename _RehashPolicy, typename _Traits,
1063  typename =
1064  __detected_or_t<false_type, __has_load_factor, _RehashPolicy>>
1066 
1067  /// Specialization when rehash policy doesn't provide load factor management.
1068  template<typename _Key, typename _Value, typename _Alloc,
1069  typename _ExtractKey, typename _Equal,
1070  typename _Hash, typename _RangeHash, typename _Unused,
1071  typename _RehashPolicy, typename _Traits>
1072  struct _Rehash_base<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1073  _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits,
1074  false_type /* Has load factor */>
1075  {
1076  };
1077 
1078  /// Specialization when rehash policy provide load factor management.
1079  template<typename _Key, typename _Value, typename _Alloc,
1080  typename _ExtractKey, typename _Equal,
1081  typename _Hash, typename _RangeHash, typename _Unused,
1082  typename _RehashPolicy, typename _Traits>
1083  struct _Rehash_base<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1084  _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits,
1085  true_type /* Has load factor */>
1086  {
1087  using __hashtable = _Hashtable<_Key, _Value, _Alloc, _ExtractKey,
1088  _Equal, _Hash, _RangeHash, _Unused,
1089  _RehashPolicy, _Traits>;
1090 
1091  float
1092  max_load_factor() const noexcept
1093  {
1094  const __hashtable* __this = static_cast<const __hashtable*>(this);
1095  return __this->__rehash_policy().max_load_factor();
1096  }
1097 
1098  void
1099  max_load_factor(float __z)
1100  {
1101  __hashtable* __this = static_cast<__hashtable*>(this);
1102  __this->__rehash_policy(_RehashPolicy(__z));
1103  }
1104 
1105  void
1106  reserve(std::size_t __n)
1107  {
1108  __hashtable* __this = static_cast<__hashtable*>(this);
1109  __this->rehash(__this->__rehash_policy()._M_bkt_for_elements(__n));
1110  }
1111  };
1112 
1113  /**
1114  * Primary class template _Hashtable_ebo_helper.
1115  *
1116  * Helper class using EBO when it is not forbidden (the type is not
1117  * final) and when it is worth it (the type is empty.)
1118  */
1119  template<int _Nm, typename _Tp,
1120  bool __use_ebo = !__is_final(_Tp) && __is_empty(_Tp)>
1122 
1123  /// Specialization using EBO.
1124  template<int _Nm, typename _Tp>
1125  struct _Hashtable_ebo_helper<_Nm, _Tp, true>
1126  : private _Tp
1127  {
1128  _Hashtable_ebo_helper() = default;
1129 
1130  template<typename _OtherTp>
1131  _Hashtable_ebo_helper(_OtherTp&& __tp)
1132  : _Tp(std::forward<_OtherTp>(__tp))
1133  { }
1134 
1135  const _Tp& _M_cget() const { return static_cast<const _Tp&>(*this); }
1136  _Tp& _M_get() { return static_cast<_Tp&>(*this); }
1137  };
1138 
1139  /// Specialization not using EBO.
1140  template<int _Nm, typename _Tp>
1141  struct _Hashtable_ebo_helper<_Nm, _Tp, false>
1142  {
1143  _Hashtable_ebo_helper() = default;
1144 
1145  template<typename _OtherTp>
1146  _Hashtable_ebo_helper(_OtherTp&& __tp)
1147  : _M_tp(std::forward<_OtherTp>(__tp))
1148  { }
1149 
1150  const _Tp& _M_cget() const { return _M_tp; }
1151  _Tp& _M_get() { return _M_tp; }
1152 
1153  private:
1154  _Tp _M_tp;
1155  };
1156 
1157  /**
1158  * Primary class template _Local_iterator_base.
1159  *
1160  * Base class for local iterators, used to iterate within a bucket
1161  * but not between buckets.
1162  */
1163  template<typename _Key, typename _Value, typename _ExtractKey,
1164  typename _Hash, typename _RangeHash, typename _Unused,
1165  bool __cache_hash_code>
1167 
1168  /**
1169  * Primary class template _Hash_code_base.
1170  *
1171  * Encapsulates two policy issues that aren't quite orthogonal.
1172  * (1) the difference between using a ranged hash function and using
1173  * the combination of a hash function and a range-hashing function.
1174  * In the former case we don't have such things as hash codes, so
1175  * we have a dummy type as placeholder.
1176  * (2) Whether or not we cache hash codes. Caching hash codes is
1177  * meaningless if we have a ranged hash function.
1178  *
1179  * We also put the key extraction objects here, for convenience.
1180  * Each specialization derives from one or more of the template
1181  * parameters to benefit from Ebo. This is important as this type
1182  * is inherited in some cases by the _Local_iterator_base type used
1183  * to implement local_iterator and const_local_iterator. As with
1184  * any iterator type we prefer to make it as small as possible.
1185  */
1186  template<typename _Key, typename _Value, typename _ExtractKey,
1187  typename _Hash, typename _RangeHash, typename _Unused,
1188  bool __cache_hash_code>
1190  : private _Hashtable_ebo_helper<1, _Hash>
1191  {
1192  private:
1194 
1195  // Gives the local iterator implementation access to _M_bucket_index().
1196  friend struct _Local_iterator_base<_Key, _Value, _ExtractKey,
1197  _Hash, _RangeHash, _Unused, false>;
1198 
1199  public:
1200  typedef _Hash hasher;
1201 
1202  hasher
1203  hash_function() const
1204  { return _M_hash(); }
1205 
1206  protected:
1207  typedef std::size_t __hash_code;
1208 
1209  // We need the default constructor for the local iterators and _Hashtable
1210  // default constructor.
1211  _Hash_code_base() = default;
1212  _Hash_code_base(const _Hash& __hash) : __ebo_hash(__hash) { }
1213 
1214  __hash_code
1215  _M_hash_code(const _Key& __k) const
1216  {
1217  static_assert(__is_invocable<const _Hash&, const _Key&>{},
1218  "hash function must be invocable with an argument of key type");
1219  return _M_hash()(__k);
1220  }
1221 
1222  std::size_t
1223  _M_bucket_index(__hash_code __c, std::size_t __bkt_count) const
1224  { return _RangeHash{}(__c, __bkt_count); }
1225 
1226  std::size_t
1227  _M_bucket_index(const _Hash_node_value<_Value, false>& __n,
1228  std::size_t __bkt_count) const
1229  noexcept( noexcept(declval<const _Hash&>()(declval<const _Key&>()))
1230  && noexcept(declval<const _RangeHash&>()((__hash_code)0,
1231  (std::size_t)0)) )
1232  {
1233  return _RangeHash{}(_M_hash_code(_ExtractKey{}(__n._M_v())),
1234  __bkt_count);
1235  }
1236 
1237  std::size_t
1238  _M_bucket_index(const _Hash_node_value<_Value, true>& __n,
1239  std::size_t __bkt_count) const
1240  noexcept( noexcept(declval<const _RangeHash&>()((__hash_code)0,
1241  (std::size_t)0)) )
1242  { return _RangeHash{}(__n._M_hash_code, __bkt_count); }
1243 
1244  void
1245  _M_store_code(_Hash_node_code_cache<false>&, __hash_code) const
1246  { }
1247 
1248  void
1249  _M_copy_code(_Hash_node_code_cache<false>&,
1250  const _Hash_node_code_cache<false>&) const
1251  { }
1252 
1253  void
1254  _M_store_code(_Hash_node_code_cache<true>& __n, __hash_code __c) const
1255  { __n._M_hash_code = __c; }
1256 
1257  void
1258  _M_copy_code(_Hash_node_code_cache<true>& __to,
1259  const _Hash_node_code_cache<true>& __from) const
1260  { __to._M_hash_code = __from._M_hash_code; }
1261 
1262  void
1263  _M_swap(_Hash_code_base& __x)
1264  { std::swap(__ebo_hash::_M_get(), __x.__ebo_hash::_M_get()); }
1265 
1266  const _Hash&
1267  _M_hash() const { return __ebo_hash::_M_cget(); }
1268  };
1269 
1270  /// Partial specialization used when nodes contain a cached hash code.
1271  template<typename _Key, typename _Value, typename _ExtractKey,
1272  typename _Hash, typename _RangeHash, typename _Unused>
1273  struct _Local_iterator_base<_Key, _Value, _ExtractKey,
1274  _Hash, _RangeHash, _Unused, true>
1275  : public _Node_iterator_base<_Value, true>
1276  {
1277  protected:
1279  using __hash_code_base = _Hash_code_base<_Key, _Value, _ExtractKey,
1280  _Hash, _RangeHash, _Unused, true>;
1281 
1282  _Local_iterator_base() = default;
1285  std::size_t __bkt, std::size_t __bkt_count)
1286  : __base_node_iter(__p), _M_bucket(__bkt), _M_bucket_count(__bkt_count)
1287  { }
1288 
1289  void
1290  _M_incr()
1291  {
1292  __base_node_iter::_M_incr();
1293  if (this->_M_cur)
1294  {
1295  std::size_t __bkt
1296  = _RangeHash{}(this->_M_cur->_M_hash_code, _M_bucket_count);
1297  if (__bkt != _M_bucket)
1298  this->_M_cur = nullptr;
1299  }
1300  }
1301 
1302  std::size_t _M_bucket;
1303  std::size_t _M_bucket_count;
1304 
1305  public:
1306  std::size_t
1307  _M_get_bucket() const { return _M_bucket; } // for debug mode
1308  };
1309 
1310  // Uninitialized storage for a _Hash_code_base.
1311  // This type is DefaultConstructible and Assignable even if the
1312  // _Hash_code_base type isn't, so that _Local_iterator_base<..., false>
1313  // can be DefaultConstructible and Assignable.
1314  template<typename _Tp, bool _IsEmpty = std::is_empty<_Tp>::value>
1315  struct _Hash_code_storage
1316  {
1317  __gnu_cxx::__aligned_buffer<_Tp> _M_storage;
1318 
1319  _Tp*
1320  _M_h() { return _M_storage._M_ptr(); }
1321 
1322  const _Tp*
1323  _M_h() const { return _M_storage._M_ptr(); }
1324  };
1325 
1326  // Empty partial specialization for empty _Hash_code_base types.
1327  template<typename _Tp>
1328  struct _Hash_code_storage<_Tp, true>
1329  {
1330  static_assert( std::is_empty<_Tp>::value, "Type must be empty" );
1331 
1332  // As _Tp is an empty type there will be no bytes written/read through
1333  // the cast pointer, so no strict-aliasing violation.
1334  _Tp*
1335  _M_h() { return reinterpret_cast<_Tp*>(this); }
1336 
1337  const _Tp*
1338  _M_h() const { return reinterpret_cast<const _Tp*>(this); }
1339  };
1340 
1341  template<typename _Key, typename _Value, typename _ExtractKey,
1342  typename _Hash, typename _RangeHash, typename _Unused>
1343  using __hash_code_for_local_iter
1344  = _Hash_code_storage<_Hash_code_base<_Key, _Value, _ExtractKey,
1345  _Hash, _RangeHash, _Unused, false>>;
1346 
1347  // Partial specialization used when hash codes are not cached
1348  template<typename _Key, typename _Value, typename _ExtractKey,
1349  typename _Hash, typename _RangeHash, typename _Unused>
1350  struct _Local_iterator_base<_Key, _Value, _ExtractKey,
1351  _Hash, _RangeHash, _Unused, false>
1352  : __hash_code_for_local_iter<_Key, _Value, _ExtractKey, _Hash, _RangeHash,
1353  _Unused>
1354  , _Node_iterator_base<_Value, false>
1355  {
1356  protected:
1357  using __hash_code_base = _Hash_code_base<_Key, _Value, _ExtractKey,
1358  _Hash, _RangeHash, _Unused, false>;
1359  using __node_iter_base = _Node_iterator_base<_Value, false>;
1360 
1361  _Local_iterator_base() : _M_bucket_count(-1) { }
1362 
1363  _Local_iterator_base(const __hash_code_base& __base,
1364  _Hash_node<_Value, false>* __p,
1365  std::size_t __bkt, std::size_t __bkt_count)
1366  : __node_iter_base(__p), _M_bucket(__bkt), _M_bucket_count(__bkt_count)
1367  { _M_init(__base); }
1368 
1369  ~_Local_iterator_base()
1370  {
1371  if (_M_bucket_count != size_t(-1))
1372  _M_destroy();
1373  }
1374 
1375  _Local_iterator_base(const _Local_iterator_base& __iter)
1376  : __node_iter_base(__iter._M_cur), _M_bucket(__iter._M_bucket)
1377  , _M_bucket_count(__iter._M_bucket_count)
1378  {
1379  if (_M_bucket_count != size_t(-1))
1380  _M_init(*__iter._M_h());
1381  }
1382 
1383  _Local_iterator_base&
1384  operator=(const _Local_iterator_base& __iter)
1385  {
1386  if (_M_bucket_count != -1)
1387  _M_destroy();
1388  this->_M_cur = __iter._M_cur;
1389  _M_bucket = __iter._M_bucket;
1390  _M_bucket_count = __iter._M_bucket_count;
1391  if (_M_bucket_count != -1)
1392  _M_init(*__iter._M_h());
1393  return *this;
1394  }
1395 
1396  void
1397  _M_incr()
1398  {
1399  __node_iter_base::_M_incr();
1400  if (this->_M_cur)
1401  {
1402  std::size_t __bkt = this->_M_h()->_M_bucket_index(*this->_M_cur,
1403  _M_bucket_count);
1404  if (__bkt != _M_bucket)
1405  this->_M_cur = nullptr;
1406  }
1407  }
1408 
1409  std::size_t _M_bucket;
1410  std::size_t _M_bucket_count;
1411 
1412  void
1413  _M_init(const __hash_code_base& __base)
1414  { ::new(this->_M_h()) __hash_code_base(__base); }
1415 
1416  void
1417  _M_destroy() { this->_M_h()->~__hash_code_base(); }
1418 
1419  public:
1420  std::size_t
1421  _M_get_bucket() const { return _M_bucket; } // for debug mode
1422  };
1423 
1424  /// local iterators
1425  template<typename _Key, typename _Value, typename _ExtractKey,
1426  typename _Hash, typename _RangeHash, typename _Unused,
1427  bool __constant_iterators, bool __cache>
1429  : public _Local_iterator_base<_Key, _Value, _ExtractKey,
1430  _Hash, _RangeHash, _Unused, __cache>
1431  {
1432  private:
1433  using __base_type = _Local_iterator_base<_Key, _Value, _ExtractKey,
1434  _Hash, _RangeHash, _Unused, __cache>;
1435  using __hash_code_base = typename __base_type::__hash_code_base;
1436 
1437  public:
1438  typedef _Value value_type;
1439  typedef typename std::conditional<__constant_iterators,
1440  const value_type*, value_type*>::type
1441  pointer;
1442  typedef typename std::conditional<__constant_iterators,
1443  const value_type&, value_type&>::type
1444  reference;
1445  typedef std::ptrdiff_t difference_type;
1447 
1448  _Local_iterator() = default;
1449 
1450  _Local_iterator(const __hash_code_base& __base,
1452  std::size_t __bkt, std::size_t __bkt_count)
1453  : __base_type(__base, __n, __bkt, __bkt_count)
1454  { }
1455 
1456  reference
1457  operator*() const
1458  { return this->_M_cur->_M_v(); }
1459 
1460  pointer
1461  operator->() const
1462  { return this->_M_cur->_M_valptr(); }
1463 
1465  operator++()
1466  {
1467  this->_M_incr();
1468  return *this;
1469  }
1470 
1472  operator++(int)
1473  {
1474  _Local_iterator __tmp(*this);
1475  this->_M_incr();
1476  return __tmp;
1477  }
1478  };
1479 
1480  /// local const_iterators
1481  template<typename _Key, typename _Value, typename _ExtractKey,
1482  typename _Hash, typename _RangeHash, typename _Unused,
1483  bool __constant_iterators, bool __cache>
1485  : public _Local_iterator_base<_Key, _Value, _ExtractKey,
1486  _Hash, _RangeHash, _Unused, __cache>
1487  {
1488  private:
1489  using __base_type = _Local_iterator_base<_Key, _Value, _ExtractKey,
1490  _Hash, _RangeHash, _Unused, __cache>;
1491  using __hash_code_base = typename __base_type::__hash_code_base;
1492 
1493  public:
1494  typedef _Value value_type;
1495  typedef const value_type* pointer;
1496  typedef const value_type& reference;
1497  typedef std::ptrdiff_t difference_type;
1499 
1500  _Local_const_iterator() = default;
1501 
1502  _Local_const_iterator(const __hash_code_base& __base,
1504  std::size_t __bkt, std::size_t __bkt_count)
1505  : __base_type(__base, __n, __bkt, __bkt_count)
1506  { }
1507 
1508  _Local_const_iterator(const _Local_iterator<_Key, _Value, _ExtractKey,
1509  _Hash, _RangeHash, _Unused,
1510  __constant_iterators,
1511  __cache>& __x)
1512  : __base_type(__x)
1513  { }
1514 
1515  reference
1516  operator*() const
1517  { return this->_M_cur->_M_v(); }
1518 
1519  pointer
1520  operator->() const
1521  { return this->_M_cur->_M_valptr(); }
1522 
1524  operator++()
1525  {
1526  this->_M_incr();
1527  return *this;
1528  }
1529 
1531  operator++(int)
1532  {
1533  _Local_const_iterator __tmp(*this);
1534  this->_M_incr();
1535  return __tmp;
1536  }
1537  };
1538 
1539  /**
1540  * Primary class template _Hashtable_base.
1541  *
1542  * Helper class adding management of _Equal functor to
1543  * _Hash_code_base type.
1544  *
1545  * Base class templates are:
1546  * - __detail::_Hash_code_base
1547  * - __detail::_Hashtable_ebo_helper
1548  */
1549  template<typename _Key, typename _Value, typename _ExtractKey,
1550  typename _Equal, typename _Hash, typename _RangeHash,
1551  typename _Unused, typename _Traits>
1553  : public _Hash_code_base<_Key, _Value, _ExtractKey, _Hash, _RangeHash,
1554  _Unused, _Traits::__hash_cached::value>,
1555  private _Hashtable_ebo_helper<0, _Equal>
1556  {
1557  public:
1558  typedef _Key key_type;
1559  typedef _Value value_type;
1560  typedef _Equal key_equal;
1561  typedef std::size_t size_type;
1562  typedef std::ptrdiff_t difference_type;
1563 
1564  using __traits_type = _Traits;
1565  using __hash_cached = typename __traits_type::__hash_cached;
1566 
1567  using __hash_code_base = _Hash_code_base<_Key, _Value, _ExtractKey,
1568  _Hash, _RangeHash, _Unused,
1569  __hash_cached::value>;
1570 
1571  using __hash_code = typename __hash_code_base::__hash_code;
1572 
1573  private:
1575 
1576  static bool
1577  _S_equals(__hash_code, const _Hash_node_code_cache<false>&)
1578  { return true; }
1579 
1580  static bool
1581  _S_node_equals(const _Hash_node_code_cache<false>&,
1583  { return true; }
1584 
1585  static bool
1586  _S_equals(__hash_code __c, const _Hash_node_code_cache<true>& __n)
1587  { return __c == __n._M_hash_code; }
1588 
1589  static bool
1590  _S_node_equals(const _Hash_node_code_cache<true>& __lhn,
1591  const _Hash_node_code_cache<true>& __rhn)
1592  { return __lhn._M_hash_code == __rhn._M_hash_code; }
1593 
1594  protected:
1595  _Hashtable_base() = default;
1596  _Hashtable_base(const _Hash& __hash, const _Equal& __eq)
1597  : __hash_code_base(__hash), _EqualEBO(__eq)
1598  { }
1599 
1600  bool
1601  _M_equals(const _Key& __k, __hash_code __c,
1602  const _Hash_node_value<_Value, __hash_cached::value>& __n) const
1603  {
1604  static_assert(__is_invocable<const _Equal&, const _Key&, const _Key&>{},
1605  "key equality predicate must be invocable with two arguments of "
1606  "key type");
1607  return _S_equals(__c, __n) && _M_eq()(__k, _ExtractKey{}(__n._M_v()));
1608  }
1609 
1610  bool
1611  _M_node_equals(
1612  const _Hash_node_value<_Value, __hash_cached::value>& __lhn,
1613  const _Hash_node_value<_Value, __hash_cached::value>& __rhn) const
1614  {
1615  return _S_node_equals(__lhn, __rhn)
1616  && _M_eq()(_ExtractKey{}(__lhn._M_v()), _ExtractKey{}(__rhn._M_v()));
1617  }
1618 
1619  void
1620  _M_swap(_Hashtable_base& __x)
1621  {
1622  __hash_code_base::_M_swap(__x);
1623  std::swap(_EqualEBO::_M_get(), __x._EqualEBO::_M_get());
1624  }
1625 
1626  const _Equal&
1627  _M_eq() const { return _EqualEBO::_M_cget(); }
1628  };
1629 
1630  /**
1631  * Primary class template _Equality.
1632  *
1633  * This is for implementing equality comparison for unordered
1634  * containers, per N3068, by John Lakos and Pablo Halpern.
1635  * Algorithmically, we follow closely the reference implementations
1636  * therein.
1637  */
1638  template<typename _Key, typename _Value, typename _Alloc,
1639  typename _ExtractKey, typename _Equal,
1640  typename _Hash, typename _RangeHash, typename _Unused,
1641  typename _RehashPolicy, typename _Traits,
1642  bool _Unique_keys = _Traits::__unique_keys::value>
1643  struct _Equality;
1644 
1645  /// unordered_map and unordered_set specializations.
1646  template<typename _Key, typename _Value, typename _Alloc,
1647  typename _ExtractKey, typename _Equal,
1648  typename _Hash, typename _RangeHash, typename _Unused,
1649  typename _RehashPolicy, typename _Traits>
1650  struct _Equality<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1651  _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits, true>
1652  {
1653  using __hashtable = _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1654  _Hash, _RangeHash, _Unused,
1655  _RehashPolicy, _Traits>;
1656 
1657  bool
1658  _M_equal(const __hashtable&) const;
1659  };
1660 
1661  template<typename _Key, typename _Value, typename _Alloc,
1662  typename _ExtractKey, typename _Equal,
1663  typename _Hash, typename _RangeHash, typename _Unused,
1664  typename _RehashPolicy, typename _Traits>
1665  bool
1666  _Equality<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1667  _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits, true>::
1668  _M_equal(const __hashtable& __other) const
1669  {
1670  using __node_type = typename __hashtable::__node_type;
1671  const __hashtable* __this = static_cast<const __hashtable*>(this);
1672  if (__this->size() != __other.size())
1673  return false;
1674 
1675  for (auto __itx = __this->begin(); __itx != __this->end(); ++__itx)
1676  {
1677  std::size_t __ybkt = __other._M_bucket_index(*__itx._M_cur);
1678  auto __prev_n = __other._M_buckets[__ybkt];
1679  if (!__prev_n)
1680  return false;
1681 
1682  for (__node_type* __n = static_cast<__node_type*>(__prev_n->_M_nxt);;
1683  __n = __n->_M_next())
1684  {
1685  if (__n->_M_v() == *__itx)
1686  break;
1687 
1688  if (!__n->_M_nxt
1689  || __other._M_bucket_index(*__n->_M_next()) != __ybkt)
1690  return false;
1691  }
1692  }
1693 
1694  return true;
1695  }
1696 
1697  /// unordered_multiset and unordered_multimap specializations.
1698  template<typename _Key, typename _Value, typename _Alloc,
1699  typename _ExtractKey, typename _Equal,
1700  typename _Hash, typename _RangeHash, typename _Unused,
1701  typename _RehashPolicy, typename _Traits>
1702  struct _Equality<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1703  _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits, false>
1704  {
1705  using __hashtable = _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1706  _Hash, _RangeHash, _Unused,
1707  _RehashPolicy, _Traits>;
1708 
1709  bool
1710  _M_equal(const __hashtable&) const;
1711  };
1712 
1713  template<typename _Key, typename _Value, typename _Alloc,
1714  typename _ExtractKey, typename _Equal,
1715  typename _Hash, typename _RangeHash, typename _Unused,
1716  typename _RehashPolicy, typename _Traits>
1717  bool
1718  _Equality<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1719  _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits, false>::
1720  _M_equal(const __hashtable& __other) const
1721  {
1722  using __node_type = typename __hashtable::__node_type;
1723  const __hashtable* __this = static_cast<const __hashtable*>(this);
1724  if (__this->size() != __other.size())
1725  return false;
1726 
1727  for (auto __itx = __this->begin(); __itx != __this->end();)
1728  {
1729  std::size_t __x_count = 1;
1730  auto __itx_end = __itx;
1731  for (++__itx_end; __itx_end != __this->end()
1732  && __this->key_eq()(_ExtractKey{}(*__itx),
1733  _ExtractKey{}(*__itx_end));
1734  ++__itx_end)
1735  ++__x_count;
1736 
1737  std::size_t __ybkt = __other._M_bucket_index(*__itx._M_cur);
1738  auto __y_prev_n = __other._M_buckets[__ybkt];
1739  if (!__y_prev_n)
1740  return false;
1741 
1742  __node_type* __y_n = static_cast<__node_type*>(__y_prev_n->_M_nxt);
1743  for (;;)
1744  {
1745  if (__this->key_eq()(_ExtractKey{}(__y_n->_M_v()),
1746  _ExtractKey{}(*__itx)))
1747  break;
1748 
1749  auto __y_ref_n = __y_n;
1750  for (__y_n = __y_n->_M_next(); __y_n; __y_n = __y_n->_M_next())
1751  if (!__other._M_node_equals(*__y_ref_n, *__y_n))
1752  break;
1753 
1754  if (!__y_n || __other._M_bucket_index(*__y_n) != __ybkt)
1755  return false;
1756  }
1757 
1758  typename __hashtable::const_iterator __ity(__y_n);
1759  for (auto __ity_end = __ity; __ity_end != __other.end(); ++__ity_end)
1760  if (--__x_count == 0)
1761  break;
1762 
1763  if (__x_count != 0)
1764  return false;
1765 
1766  if (!std::is_permutation(__itx, __itx_end, __ity))
1767  return false;
1768 
1769  __itx = __itx_end;
1770  }
1771  return true;
1772  }
1773 
1774  /**
1775  * This type deals with all allocation and keeps an allocator instance
1776  * through inheritance to benefit from EBO when possible.
1777  */
1778  template<typename _NodeAlloc>
1779  struct _Hashtable_alloc : private _Hashtable_ebo_helper<0, _NodeAlloc>
1780  {
1781  private:
1783  public:
1784  using __node_type = typename _NodeAlloc::value_type;
1785  using __node_alloc_type = _NodeAlloc;
1786  // Use __gnu_cxx to benefit from _S_always_equal and al.
1788 
1789  using __value_alloc_traits = typename __node_alloc_traits::template
1790  rebind_traits<typename __node_type::value_type>;
1791 
1792  using __node_ptr = __node_type*;
1793  using __node_base = _Hash_node_base;
1794  using __node_base_ptr = __node_base*;
1795  using __buckets_alloc_type =
1796  __alloc_rebind<__node_alloc_type, __node_base_ptr>;
1798  using __buckets_ptr = __node_base_ptr*;
1799 
1800  _Hashtable_alloc() = default;
1801  _Hashtable_alloc(const _Hashtable_alloc&) = default;
1802  _Hashtable_alloc(_Hashtable_alloc&&) = default;
1803 
1804  template<typename _Alloc>
1805  _Hashtable_alloc(_Alloc&& __a)
1806  : __ebo_node_alloc(std::forward<_Alloc>(__a))
1807  { }
1808 
1809  __node_alloc_type&
1810  _M_node_allocator()
1811  { return __ebo_node_alloc::_M_get(); }
1812 
1813  const __node_alloc_type&
1814  _M_node_allocator() const
1815  { return __ebo_node_alloc::_M_cget(); }
1816 
1817  // Allocate a node and construct an element within it.
1818  template<typename... _Args>
1819  __node_ptr
1820  _M_allocate_node(_Args&&... __args);
1821 
1822  // Destroy the element within a node and deallocate the node.
1823  void
1824  _M_deallocate_node(__node_ptr __n);
1825 
1826  // Deallocate a node.
1827  void
1828  _M_deallocate_node_ptr(__node_ptr __n);
1829 
1830  // Deallocate the linked list of nodes pointed to by __n.
1831  // The elements within the nodes are destroyed.
1832  void
1833  _M_deallocate_nodes(__node_ptr __n);
1834 
1836  _M_allocate_buckets(std::size_t __bkt_count);
1837 
1838  void
1839  _M_deallocate_buckets(__buckets_ptr, std::size_t __bkt_count);
1840  };
1841 
1842  // Definitions of class template _Hashtable_alloc's out-of-line member
1843  // functions.
1844  template<typename _NodeAlloc>
1845  template<typename... _Args>
1846  auto
1848  -> __node_ptr
1849  {
1850  auto __nptr = __node_alloc_traits::allocate(_M_node_allocator(), 1);
1851  __node_ptr __n = std::__to_address(__nptr);
1852  __try
1853  {
1854  ::new ((void*)__n) __node_type;
1855  __node_alloc_traits::construct(_M_node_allocator(),
1856  __n->_M_valptr(),
1857  std::forward<_Args>(__args)...);
1858  return __n;
1859  }
1860  __catch(...)
1861  {
1862  __node_alloc_traits::deallocate(_M_node_allocator(), __nptr, 1);
1863  __throw_exception_again;
1864  }
1865  }
1866 
1867  template<typename _NodeAlloc>
1868  void
1869  _Hashtable_alloc<_NodeAlloc>::_M_deallocate_node(__node_ptr __n)
1870  {
1871  __node_alloc_traits::destroy(_M_node_allocator(), __n->_M_valptr());
1872  _M_deallocate_node_ptr(__n);
1873  }
1874 
1875  template<typename _NodeAlloc>
1876  void
1877  _Hashtable_alloc<_NodeAlloc>::_M_deallocate_node_ptr(__node_ptr __n)
1878  {
1879  typedef typename __node_alloc_traits::pointer _Ptr;
1880  auto __ptr = std::pointer_traits<_Ptr>::pointer_to(*__n);
1881  __n->~__node_type();
1882  __node_alloc_traits::deallocate(_M_node_allocator(), __ptr, 1);
1883  }
1884 
1885  template<typename _NodeAlloc>
1886  void
1887  _Hashtable_alloc<_NodeAlloc>::_M_deallocate_nodes(__node_ptr __n)
1888  {
1889  while (__n)
1890  {
1891  __node_ptr __tmp = __n;
1892  __n = __n->_M_next();
1893  _M_deallocate_node(__tmp);
1894  }
1895  }
1896 
1897  template<typename _NodeAlloc>
1898  auto
1899  _Hashtable_alloc<_NodeAlloc>::_M_allocate_buckets(std::size_t __bkt_count)
1900  -> __buckets_ptr
1901  {
1902  __buckets_alloc_type __alloc(_M_node_allocator());
1903 
1904  auto __ptr = __buckets_alloc_traits::allocate(__alloc, __bkt_count);
1905  __buckets_ptr __p = std::__to_address(__ptr);
1906  __builtin_memset(__p, 0, __bkt_count * sizeof(__node_base_ptr));
1907  return __p;
1908  }
1909 
1910  template<typename _NodeAlloc>
1911  void
1912  _Hashtable_alloc<_NodeAlloc>::
1913  _M_deallocate_buckets(__buckets_ptr __bkts,
1914  std::size_t __bkt_count)
1915  {
1916  typedef typename __buckets_alloc_traits::pointer _Ptr;
1917  auto __ptr = std::pointer_traits<_Ptr>::pointer_to(*__bkts);
1918  __buckets_alloc_type __alloc(_M_node_allocator());
1919  __buckets_alloc_traits::deallocate(__alloc, __ptr, __bkt_count);
1920  }
1921 
1922  //@} hashtable-detail
1923 } // namespace __detail
1924 _GLIBCXX_END_NAMESPACE_VERSION
1925 } // namespace std
1926 
1927 #endif // _HASHTABLE_POLICY_H
__gnu_cxx::__alloc_traits
Uniform interface to C++98 and C++11 allocators.
Definition: ext/alloc_traits.h:52
std::conditional
Define a member typedef type to one of two argument types.
Definition: type_traits:2161
std::forward_as_tuple
constexpr tuple< _Elements &&... > forward_as_tuple(_Elements &&... __args) noexcept
std::forward_as_tuple
Definition: tuple:1569
std::__detail::_Hash_node_base
Definition: hashtable_policy.h:215
std::__iterator_category
constexpr iterator_traits< _Iter >::iterator_category __iterator_category(const _Iter &)
Definition: stl_iterator_base_types.h:238
std::__detail::_Hash_node_value_base
Definition: hashtable_policy.h:230
std
ISO C++ entities toplevel namespace is std.
std::tuple
Primary class template, tuple.
Definition: tuple:600
std::__detail::_Hashtable_ebo_helper
Definition: hashtable_policy.h:1121
std::__detail::_Hashtable_traits
Definition: hashtable_policy.h:200
operator->
element_type * operator->() const
Smart pointer dereferencing.
Definition: auto_ptr.h:105
std::iterator_traits
Traits class for iterators.
Definition: stl_iterator_base_types.h:178
std::__detail::_Rehash_base
Definition: hashtable_policy.h:1065
std::__detail::_Hashtable_alloc
Definition: hashtable_policy.h:1780
stl_algobase.h
std::distance
constexpr iterator_traits< _InputIterator >::difference_type distance(_InputIterator __first, _InputIterator __last)
A generalization of pointer arithmetic.
Definition: stl_iterator_base_funcs.h:138
std::true_type
integral_constant< bool, true > true_type
The type used as a compile-time boolean with true value.
Definition: type_traits:75
std::__detail::_Power2_rehash_policy
Rehash policy providing power of 2 bucket numbers. Avoids modulo operations.
Definition: hashtable_policy.h:522
tuple
__gnu_debug::__base
constexpr _Iterator __base(_Iterator __it)
Definition: helper_functions.h:303
std::integral_constant
integral_constant
Definition: type_traits:58
std::pair
Struct holding two objects of arbitrary type.
Definition: stl_pair.h:213
std::forward_iterator_tag
Forward iterators support a superset of input iterator operations.
Definition: stl_iterator_base_types.h:99
std::piecewise_construct
constexpr piecewise_construct_t piecewise_construct
Tag for piecewise construction of std::pair objects.
Definition: stl_pair.h:83
std::__detail::_Local_iterator
local iterators
Definition: hashtable_policy.h:1431
std::__detail::_Node_const_iterator
Node const_iterators, used to iterate through all the hashtable.
Definition: hashtable_policy.h:369
std::move
constexpr std::remove_reference< _Tp >::type && move(_Tp &&__t) noexcept
Convert a value to an rvalue.
Definition: move.h:101
std::enable_if
Define a member typedef type only if a boolean constant is true.
Definition: type_traits:2143
std::__detail::_Insert_base
Definition: hashtable_policy.h:791
operator=
auto_ptr & operator=(auto_ptr &__a)
auto_ptr assignment operator.
Definition: auto_ptr.h:47
std::__detail::_Mask_range_hashing
Range hashing function assuming that second arg is a power of 2.
Definition: hashtable_policy.h:493
std::swap
void swap(any &__x, any &__y) noexcept
Exchange the states of two any objects.
Definition: any:412
std::allocator_traits
Uniform interface to all allocator types.
Definition: bits/alloc_traits.h:87
std::initializer_list
initializer_list
Definition: initializer_list:48
std::__detail::_Equality
Definition: hashtable_policy.h:1643
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:439
std::__detail::_Node_iterator
Node iterators, used to iterate through all the hashtable.
Definition: hashtable_policy.h:318
std::pointer_traits
Uniform interface to all pointer-like types.
Definition: ptr_traits.h:84
std::__detail::_Map_base
Definition: hashtable_policy.h:644
std::_Hashtable
Definition: bits/hashtable.h:187
std::__detail::_Hash_code_base
Definition: hashtable_policy.h:1191
std::__detail::_Hash_node_code_cache< true >
Definition: hashtable_policy.h:264
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:444
numeric_traits.h
std::input_iterator_tag
Marking input iterators.
Definition: stl_iterator_base_types.h:93
std::__detail::_Local_const_iterator
local const_iterators
Definition: hashtable_policy.h:1487
std::__detail::_Mod_range_hashing
Default range hashing function: use division to fold a large number into the range [0,...
Definition: hashtable_policy.h:423
std::operator*
constexpr complex< _Tp > operator*(const complex< _Tp > &__x, const complex< _Tp > &__y)
Return new complex value x times y.
Definition: complex:392
std::__detail::_Node_iterator_base
Base class for node iterators.
Definition: hashtable_policy.h:288
std::is_constructible
is_constructible
Definition: type_traits:913
std::tuple_element
tuple_element
Definition: array:442
__gnu_cxx::__int_traits
__numeric_traits_integer< _Tp > __int_traits
Convenience alias for __numeric_traits<integer-type>.
Definition: numeric_traits.h:136
std::__detail::_Insert
Definition: hashtable_policy.h:954
std::__detail::_Hashtable_base
Definition: hashtable_policy.h:1556
std::is_empty
is_empty
Definition: type_traits:722
std::__detail::_Hash_node
Definition: hashtable_policy.h:279
std::__detail::__clp2
std::size_t __clp2(std::size_t __n) noexcept
Compute closest power of 2 not less than __n.
Definition: hashtable_policy.h:506
std::__detail::_Local_iterator_base
Definition: hashtable_policy.h:1166
std::__detail::_Hash_node_code_cache
Definition: hashtable_policy.h:257