1 // hashtable.h header -*- C++ -*-
3 // Copyright (C) 2007-2013 Free Software Foundation, Inc.
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)
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.
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.
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/>.
25 /** @file bits/hashtable.h
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{unordered_map, unordered_set}
31 #define _HASHTABLE_H 1
33 #pragma GCC system_header
35 #include <bits/hashtable_policy.h>
37 namespace std
_GLIBCXX_VISIBILITY(default)
39 _GLIBCXX_BEGIN_NAMESPACE_VERSION
41 template<typename _Tp
, typename _Hash
>
43 = __not_
<__and_
<// Do not cache for fast hasher.
44 __is_fast_hash
<_Hash
>,
45 // Mandatory to make local_iterator default
46 // constructible and assignable.
47 is_default_constructible
<_Hash
>,
48 is_copy_assignable
<_Hash
>,
49 // Mandatory to have erase not throwing.
50 __detail::__is_noexcept_hash
<_Tp
, _Hash
>>>;
53 * Primary class template _Hashtable.
55 * @ingroup hashtable-detail
57 * @tparam _Value CopyConstructible type.
59 * @tparam _Key CopyConstructible type.
61 * @tparam _Alloc An allocator type
62 * ([lib.allocator.requirements]) whose _Alloc::value_type is
63 * _Value. As a conforming extension, we allow for
64 * _Alloc::value_type != _Value.
66 * @tparam _ExtractKey Function object that takes an object of type
67 * _Value and returns a value of type _Key.
69 * @tparam _Equal Function object that takes two objects of type k
70 * and returns a bool-like value that is true if the two objects
71 * are considered equal.
73 * @tparam _H1 The hash function. A unary function object with
74 * argument type _Key and result type size_t. Return values should
75 * be distributed over the entire range [0, numeric_limits<size_t>:::max()].
77 * @tparam _H2 The range-hashing function (in the terminology of
78 * Tavori and Dreizin). A binary function object whose argument
79 * types and result type are all size_t. Given arguments r and N,
80 * the return value is in the range [0, N).
82 * @tparam _Hash The ranged hash function (Tavori and Dreizin). A
83 * binary function whose argument types are _Key and size_t and
84 * whose result type is size_t. Given arguments k and N, the
85 * return value is in the range [0, N). Default: hash(k, N) =
86 * h2(h1(k), N). If _Hash is anything other than the default, _H1
87 * and _H2 are ignored.
89 * @tparam _RehashPolicy Policy class with three members, all of
90 * which govern the bucket count. _M_next_bkt(n) returns a bucket
91 * count no smaller than n. _M_bkt_for_elements(n) returns a
92 * bucket count appropriate for an element count of n.
93 * _M_need_rehash(n_bkt, n_elt, n_ins) determines whether, if the
94 * current bucket count is n_bkt and the current element count is
95 * n_elt, we need to increase the bucket count. If so, returns
96 * make_pair(true, n), where n is the new bucket count. If not,
97 * returns make_pair(false, <anything>)
99 * @tparam _Traits Compile-time class with three boolean
100 * std::integral_constant members: __cache_hash_code, __constant_iterators,
103 * Each _Hashtable data structure has:
105 * - _Bucket[] _M_buckets
106 * - _Hash_node_base _M_before_begin
107 * - size_type _M_bucket_count
108 * - size_type _M_element_count
110 * with _Bucket being _Hash_node* and _Hash_node containing:
112 * - _Hash_node* _M_next
114 * - size_t _M_hash_code if cache_hash_code is true
116 * In terms of Standard containers the hashtable is like the aggregation of:
118 * - std::forward_list<_Node> containing the elements
119 * - std::vector<std::forward_list<_Node>::iterator> representing the buckets
121 * The non-empty buckets contain the node before the first node in the
122 * bucket. This design makes it possible to implement something like a
123 * std::forward_list::insert_after on container insertion and
124 * std::forward_list::erase_after on container erase
125 * calls. _M_before_begin is equivalent to
126 * std::forward_list::before_begin. Empty buckets contain
127 * nullptr. Note that one of the non-empty buckets contains
128 * &_M_before_begin which is not a dereferenceable node so the
129 * node pointer in a bucket shall never be dereferenced, only its
132 * Walking through a bucket's nodes requires a check on the hash code to
133 * see if each node is still in the bucket. Such a design assumes a
134 * quite efficient hash functor and is one of the reasons it is
135 * highly advisable to set __cache_hash_code to true.
137 * The container iterators are simply built from nodes. This way
138 * incrementing the iterator is perfectly efficient independent of
139 * how many empty buckets there are in the container.
141 * On insert we compute the element's hash code and use it to find the
142 * bucket index. If the element must be inserted in an empty bucket
143 * we add it at the beginning of the singly linked list and make the
144 * bucket point to _M_before_begin. The bucket that used to point to
145 * _M_before_begin, if any, is updated to point to its new before
148 * On erase, the simple iterator design requires using the hash
149 * functor to get the index of the bucket to update. For this
150 * reason, when __cache_hash_code is set to false the hash functor must
151 * not throw and this is enforced by a static assertion.
153 * Functionality is implemented by decomposition into base classes,
154 * where the derived _Hashtable class is used in _Map_base,
155 * _Insert, _Rehash_base, and _Equality base classes to access the
156 * "this" pointer. _Hashtable_base is used in the base classes as a
157 * non-recursive, fully-completed-type so that detailed nested type
158 * information, such as iterator type and node type, can be
159 * used. This is similar to the "Curiously Recurring Template
160 * Pattern" (CRTP) technique, but uses a reconstructed, not
161 * explicitly passed, template pattern.
163 * Base class templates are:
164 * - __detail::_Hashtable_base
165 * - __detail::_Map_base
166 * - __detail::_Insert
167 * - __detail::_Rehash_base
168 * - __detail::_Equality
170 template<typename _Key
, typename _Value
, typename _Alloc
,
171 typename _ExtractKey
, typename _Equal
,
172 typename _H1
, typename _H2
, typename _Hash
,
173 typename _RehashPolicy
, typename _Traits
>
175 : public __detail::_Hashtable_base
<_Key
, _Value
, _ExtractKey
, _Equal
,
176 _H1
, _H2
, _Hash
, _Traits
>,
177 public __detail::_Map_base
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
178 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>,
179 public __detail::_Insert
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
180 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>,
181 public __detail::_Rehash_base
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
182 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>,
183 public __detail::_Equality
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
184 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>,
185 private __detail::_Hashtable_alloc
<
186 typename __alloctr_rebind
<_Alloc
,
187 __detail::_Hash_node
<_Value
,
188 _Traits::__hash_cached::value
> >::__type
>
190 using __traits_type
= _Traits
;
191 using __hash_cached
= typename
__traits_type::__hash_cached
;
192 using __node_type
= __detail::_Hash_node
<_Value
, __hash_cached::value
>;
193 using __node_alloc_type
=
194 typename __alloctr_rebind
<_Alloc
, __node_type
>::__type
;
196 using __hashtable_alloc
= __detail::_Hashtable_alloc
<__node_alloc_type
>;
198 using __value_alloc_traits
=
199 typename
__hashtable_alloc::__value_alloc_traits
;
200 using __node_alloc_traits
=
201 typename
__hashtable_alloc::__node_alloc_traits
;
202 using __node_base
= typename
__hashtable_alloc::__node_base
;
203 using __bucket_type
= typename
__hashtable_alloc::__bucket_type
;
206 typedef _Key key_type
;
207 typedef _Value value_type
;
208 typedef _Alloc allocator_type
;
209 typedef _Equal key_equal
;
211 // mapped_type, if present, comes from _Map_base.
212 // hasher, if present, comes from _Hash_code_base/_Hashtable_base.
213 typedef typename
__value_alloc_traits::pointer pointer
;
214 typedef typename
__value_alloc_traits::const_pointer const_pointer
;
215 typedef value_type
& reference
;
216 typedef const value_type
& const_reference
;
219 using __rehash_type
= _RehashPolicy
;
220 using __rehash_state
= typename
__rehash_type::_State
;
222 using __constant_iterators
= typename
__traits_type::__constant_iterators
;
223 using __unique_keys
= typename
__traits_type::__unique_keys
;
225 using __key_extract
= typename
std::conditional
<
226 __constant_iterators::value
,
228 __detail::_Select1st
>::type
;
230 using __hashtable_base
= __detail::
231 _Hashtable_base
<_Key
, _Value
, _ExtractKey
,
232 _Equal
, _H1
, _H2
, _Hash
, _Traits
>;
234 using __hash_code_base
= typename
__hashtable_base::__hash_code_base
;
235 using __hash_code
= typename
__hashtable_base::__hash_code
;
236 using __ireturn_type
= typename
__hashtable_base::__ireturn_type
;
238 using __map_base
= __detail::_Map_base
<_Key
, _Value
, _Alloc
, _ExtractKey
,
239 _Equal
, _H1
, _H2
, _Hash
,
240 _RehashPolicy
, _Traits
>;
242 using __rehash_base
= __detail::_Rehash_base
<_Key
, _Value
, _Alloc
,
245 _RehashPolicy
, _Traits
>;
247 using __eq_base
= __detail::_Equality
<_Key
, _Value
, _Alloc
, _ExtractKey
,
248 _Equal
, _H1
, _H2
, _Hash
,
249 _RehashPolicy
, _Traits
>;
251 using __reuse_or_alloc_node_type
=
252 __detail::_ReuseOrAllocNode
<__node_alloc_type
>;
254 // Metaprogramming for picking apart hash caching.
255 template<typename _Cond
>
256 using __if_hash_cached
= __or_
<__not_
<__hash_cached
>, _Cond
>;
258 template<typename _Cond
>
259 using __if_hash_not_cached
= __or_
<__hash_cached
, _Cond
>;
261 // Compile-time diagnostics.
263 // Getting a bucket index from a node shall not throw because it is used
264 // in methods (erase, swap...) that shall not throw.
265 static_assert(noexcept(declval
<const _Hashtable
&>()
266 ._M_bucket_index((const __node_type
*)nullptr,
268 "Cache the hash code or qualify your functors involved"
269 " in hash code and bucket index computation with noexcept");
271 // Following two static assertions are necessary to guarantee
272 // that local_iterator will be default constructible.
274 // When hash codes are cached local iterator inherits from H2 functor
275 // which must then be default constructible.
276 static_assert(__if_hash_cached
<is_default_constructible
<_H2
>>::value
,
277 "Functor used to map hash code to bucket index"
278 " must be default constructible");
280 // _Hash_code_base has a protected default constructor, so use this
281 // derived type to tell if it's usable.
282 struct __access_protected_ctor
: __hash_code_base
{ };
284 // When hash codes are not cached local iterator inherits from
285 // __hash_code_base above to compute node bucket index so it has to be
286 // default constructible.
287 static_assert(__if_hash_not_cached
<
288 is_default_constructible
<__access_protected_ctor
>>::value
,
289 "Cache the hash code or make functors involved in hash code"
290 " and bucket index computation default constructible");
292 // When hash codes are not cached local iterator inherits from
293 // __hash_code_base above to compute node bucket index so it has to be
295 static_assert(__if_hash_not_cached
<
296 is_copy_assignable
<__hash_code_base
>>::value
,
297 "Cache the hash code or make functors involved in hash code"
298 " and bucket index computation copy assignable");
300 template<typename _Keya
, typename _Valuea
, typename _Alloca
,
301 typename _ExtractKeya
, typename _Equala
,
302 typename _H1a
, typename _H2a
, typename _Hasha
,
303 typename _RehashPolicya
, typename _Traitsa
,
305 friend struct __detail::_Map_base
;
307 template<typename _Keya
, typename _Valuea
, typename _Alloca
,
308 typename _ExtractKeya
, typename _Equala
,
309 typename _H1a
, typename _H2a
, typename _Hasha
,
310 typename _RehashPolicya
, typename _Traitsa
>
311 friend struct __detail::_Insert_base
;
313 template<typename _Keya
, typename _Valuea
, typename _Alloca
,
314 typename _ExtractKeya
, typename _Equala
,
315 typename _H1a
, typename _H2a
, typename _Hasha
,
316 typename _RehashPolicya
, typename _Traitsa
,
317 bool _Constant_iteratorsa
, bool _Unique_keysa
>
318 friend struct __detail::_Insert
;
321 using size_type
= typename
__hashtable_base::size_type
;
322 using difference_type
= typename
__hashtable_base::difference_type
;
324 using iterator
= typename
__hashtable_base::iterator
;
325 using const_iterator
= typename
__hashtable_base::const_iterator
;
327 using local_iterator
= typename
__hashtable_base::local_iterator
;
328 using const_local_iterator
= typename
__hashtable_base::
329 const_local_iterator
;
332 __bucket_type
* _M_buckets
;
333 size_type _M_bucket_count
;
334 __node_base _M_before_begin
;
335 size_type _M_element_count
;
336 _RehashPolicy _M_rehash_policy
;
339 _M_base_alloc() { return *this; }
341 using __hashtable_alloc::_M_deallocate_buckets
;
344 _M_deallocate_buckets()
345 { this->_M_deallocate_buckets(_M_buckets
, _M_bucket_count
); }
347 // Gets bucket begin, deals with the fact that non-empty buckets contain
348 // their before begin node.
350 _M_bucket_begin(size_type __bkt
) const;
354 { return static_cast<__node_type
*>(_M_before_begin
._M_nxt
); }
356 template<typename _NodeGenerator
>
358 _M_assign(const _Hashtable
&, const _NodeGenerator
&);
361 _M_move_assign(_Hashtable
&&, std::true_type
);
364 _M_move_assign(_Hashtable
&&, std::false_type
);
370 // Constructor, destructor, assignment, swap
371 _Hashtable(size_type __bucket_hint
,
372 const _H1
&, const _H2
&, const _Hash
&,
373 const _Equal
&, const _ExtractKey
&,
374 const allocator_type
&);
376 template<typename _InputIterator
>
377 _Hashtable(_InputIterator __first
, _InputIterator __last
,
378 size_type __bucket_hint
,
379 const _H1
&, const _H2
&, const _Hash
&,
380 const _Equal
&, const _ExtractKey
&,
381 const allocator_type
&);
383 _Hashtable(const _Hashtable
&);
385 _Hashtable(_Hashtable
&&) noexcept
;
387 _Hashtable(const _Hashtable
&, const allocator_type
&);
389 _Hashtable(_Hashtable
&&, const allocator_type
&);
391 // Use delegating constructors.
393 _Hashtable(const allocator_type
& __a
)
394 : _Hashtable(10, _H1(), __detail::_Mod_range_hashing(),
395 __detail::_Default_ranged_hash(), key_equal(),
396 __key_extract(), __a
)
400 _Hashtable(size_type __n
= 10,
401 const _H1
& __hf
= _H1(),
402 const key_equal
& __eql
= key_equal(),
403 const allocator_type
& __a
= allocator_type())
404 : _Hashtable(__n
, __hf
, __detail::_Mod_range_hashing(),
405 __detail::_Default_ranged_hash(), __eql
,
406 __key_extract(), __a
)
409 template<typename _InputIterator
>
410 _Hashtable(_InputIterator __f
, _InputIterator __l
,
412 const _H1
& __hf
= _H1(),
413 const key_equal
& __eql
= key_equal(),
414 const allocator_type
& __a
= allocator_type())
415 : _Hashtable(__f
, __l
, __n
, __hf
, __detail::_Mod_range_hashing(),
416 __detail::_Default_ranged_hash(), __eql
,
417 __key_extract(), __a
)
420 _Hashtable(initializer_list
<value_type
> __l
,
422 const _H1
& __hf
= _H1(),
423 const key_equal
& __eql
= key_equal(),
424 const allocator_type
& __a
= allocator_type())
425 : _Hashtable(__l
.begin(), __l
.end(), __n
, __hf
,
426 __detail::_Mod_range_hashing(),
427 __detail::_Default_ranged_hash(), __eql
,
428 __key_extract(), __a
)
432 operator=(const _Hashtable
& __ht
);
435 operator=(_Hashtable
&& __ht
)
436 noexcept(__node_alloc_traits::_S_nothrow_move())
438 constexpr bool __move_storage
=
439 __node_alloc_traits::_S_propagate_on_move_assign()
440 || __node_alloc_traits::_S_always_equal();
441 _M_move_assign(std::move(__ht
),
442 integral_constant
<bool, __move_storage
>());
447 operator=(initializer_list
<value_type
> __l
)
449 __reuse_or_alloc_node_type
__roan(_M_begin(), *this);
450 _M_before_begin
._M_nxt
= nullptr;
452 this->_M_insert_range(__l
.begin(), __l
.end(), __roan
);
456 ~_Hashtable() noexcept
;
460 noexcept(__node_alloc_traits::_S_nothrow_swap());
462 // Basic container operations
465 { return iterator(_M_begin()); }
468 begin() const noexcept
469 { return const_iterator(_M_begin()); }
473 { return iterator(nullptr); }
477 { return const_iterator(nullptr); }
480 cbegin() const noexcept
481 { return const_iterator(_M_begin()); }
484 cend() const noexcept
485 { return const_iterator(nullptr); }
488 size() const noexcept
489 { return _M_element_count
; }
492 empty() const noexcept
493 { return size() == 0; }
496 get_allocator() const noexcept
497 { return allocator_type(this->_M_node_allocator()); }
500 max_size() const noexcept
501 { return __node_alloc_traits::max_size(this->_M_node_allocator()); }
506 { return this->_M_eq(); }
508 // hash_function, if present, comes from _Hash_code_base.
512 bucket_count() const noexcept
513 { return _M_bucket_count
; }
516 max_bucket_count() const noexcept
517 { return max_size(); }
520 bucket_size(size_type __n
) const
521 { return std::distance(begin(__n
), end(__n
)); }
524 bucket(const key_type
& __k
) const
525 { return _M_bucket_index(__k
, this->_M_hash_code(__k
)); }
530 return local_iterator(*this, _M_bucket_begin(__n
),
531 __n
, _M_bucket_count
);
536 { return local_iterator(*this, nullptr, __n
, _M_bucket_count
); }
539 begin(size_type __n
) const
541 return const_local_iterator(*this, _M_bucket_begin(__n
),
542 __n
, _M_bucket_count
);
546 end(size_type __n
) const
547 { return const_local_iterator(*this, nullptr, __n
, _M_bucket_count
); }
551 cbegin(size_type __n
) const
553 return const_local_iterator(*this, _M_bucket_begin(__n
),
554 __n
, _M_bucket_count
);
558 cend(size_type __n
) const
559 { return const_local_iterator(*this, nullptr, __n
, _M_bucket_count
); }
562 load_factor() const noexcept
564 return static_cast<float>(size()) / static_cast<float>(bucket_count());
567 // max_load_factor, if present, comes from _Rehash_base.
569 // Generalization of max_load_factor. Extension, not found in
570 // TR1. Only useful if _RehashPolicy is something other than
573 __rehash_policy() const
574 { return _M_rehash_policy
; }
577 __rehash_policy(const _RehashPolicy
&);
581 find(const key_type
& __k
);
584 find(const key_type
& __k
) const;
587 count(const key_type
& __k
) const;
589 std::pair
<iterator
, iterator
>
590 equal_range(const key_type
& __k
);
592 std::pair
<const_iterator
, const_iterator
>
593 equal_range(const key_type
& __k
) const;
596 // Bucket index computation helpers.
598 _M_bucket_index(__node_type
* __n
) const noexcept
599 { return __hash_code_base::_M_bucket_index(__n
, _M_bucket_count
); }
602 _M_bucket_index(const key_type
& __k
, __hash_code __c
) const
603 { return __hash_code_base::_M_bucket_index(__k
, __c
, _M_bucket_count
); }
605 // Find and insert helper functions and types
606 // Find the node before the one matching the criteria.
608 _M_find_before_node(size_type
, const key_type
&, __hash_code
) const;
611 _M_find_node(size_type __bkt
, const key_type
& __key
,
612 __hash_code __c
) const
614 __node_base
* __before_n
= _M_find_before_node(__bkt
, __key
, __c
);
616 return static_cast<__node_type
*>(__before_n
->_M_nxt
);
620 // Insert a node at the beginning of a bucket.
622 _M_insert_bucket_begin(size_type
, __node_type
*);
624 // Remove the bucket first node
626 _M_remove_bucket_begin(size_type __bkt
, __node_type
* __next_n
,
627 size_type __next_bkt
);
629 // Get the node before __n in the bucket __bkt
631 _M_get_previous_node(size_type __bkt
, __node_base
* __n
);
633 // Insert node with hash code __code, in bucket bkt if no rehash (assumes
634 // no element with its key already present). Take ownership of the node,
635 // deallocate it on exception.
637 _M_insert_unique_node(size_type __bkt
, __hash_code __code
,
640 // Insert node with hash code __code. Take ownership of the node,
641 // deallocate it on exception.
643 _M_insert_multi_node(__node_type
* __hint
,
644 __hash_code __code
, __node_type
* __n
);
646 template<typename
... _Args
>
647 std::pair
<iterator
, bool>
648 _M_emplace(std::true_type
, _Args
&&... __args
);
650 template<typename
... _Args
>
652 _M_emplace(std::false_type __uk
, _Args
&&... __args
)
653 { return _M_emplace(cend(), __uk
, std::forward
<_Args
>(__args
)...); }
655 // Emplace with hint, useless when keys are unique.
656 template<typename
... _Args
>
658 _M_emplace(const_iterator
, std::true_type __uk
, _Args
&&... __args
)
659 { return _M_emplace(__uk
, std::forward
<_Args
>(__args
)...).first
; }
661 template<typename
... _Args
>
663 _M_emplace(const_iterator
, std::false_type
, _Args
&&... __args
);
665 template<typename _Arg
, typename _NodeGenerator
>
666 std::pair
<iterator
, bool>
667 _M_insert(_Arg
&&, const _NodeGenerator
&, std::true_type
);
669 template<typename _Arg
, typename _NodeGenerator
>
671 _M_insert(_Arg
&& __arg
, const _NodeGenerator
& __node_gen
,
672 std::false_type __uk
)
674 return _M_insert(cend(), std::forward
<_Arg
>(__arg
), __node_gen
,
678 // Insert with hint, not used when keys are unique.
679 template<typename _Arg
, typename _NodeGenerator
>
681 _M_insert(const_iterator
, _Arg
&& __arg
, const _NodeGenerator
& __node_gen
,
685 _M_insert(std::forward
<_Arg
>(__arg
), __node_gen
, __uk
).first
;
688 // Insert with hint when keys are not unique.
689 template<typename _Arg
, typename _NodeGenerator
>
691 _M_insert(const_iterator
, _Arg
&&, const _NodeGenerator
&, std::false_type
);
694 _M_erase(std::true_type
, const key_type
&);
697 _M_erase(std::false_type
, const key_type
&);
700 _M_erase(size_type __bkt
, __node_base
* __prev_n
, __node_type
* __n
);
704 template<typename
... _Args
>
706 emplace(_Args
&&... __args
)
707 { return _M_emplace(__unique_keys(), std::forward
<_Args
>(__args
)...); }
709 template<typename
... _Args
>
711 emplace_hint(const_iterator __hint
, _Args
&&... __args
)
713 return _M_emplace(__hint
, __unique_keys(),
714 std::forward
<_Args
>(__args
)...);
717 // Insert member functions via inheritance.
721 erase(const_iterator
);
726 { return erase(const_iterator(__it
)); }
729 erase(const key_type
& __k
)
731 if (__builtin_expect(_M_bucket_count
== 0, false))
733 return _M_erase(__unique_keys(), __k
);
737 erase(const_iterator
, const_iterator
);
742 // Set number of buckets to be appropriate for container of n element.
743 void rehash(size_type __n
);
746 // reserve, if present, comes from _Rehash_base.
749 // Helper rehash method used when keys are unique.
750 void _M_rehash_aux(size_type __n
, std::true_type
);
752 // Helper rehash method used when keys can be non-unique.
753 void _M_rehash_aux(size_type __n
, std::false_type
);
755 // Unconditionally change size of bucket array to n, restore
756 // hash policy state to __state on exception.
757 void _M_rehash(size_type __n
, const __rehash_state
& __state
);
761 // Definitions of class template _Hashtable's out-of-line member functions.
762 template<typename _Key
, typename _Value
,
763 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
764 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
766 typename _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
,
767 _Equal
, _H1
, _H2
, _Hash
, _RehashPolicy
,
768 _Traits
>::__node_type
*
769 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
770 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
771 _M_bucket_begin(size_type __bkt
) const
773 __node_base
* __n
= _M_buckets
[__bkt
];
774 return __n
? static_cast<__node_type
*>(__n
->_M_nxt
) : nullptr;
777 template<typename _Key
, typename _Value
,
778 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
779 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
781 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
782 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
783 _Hashtable(size_type __bucket_hint
,
784 const _H1
& __h1
, const _H2
& __h2
, const _Hash
& __h
,
785 const _Equal
& __eq
, const _ExtractKey
& __exk
,
786 const allocator_type
& __a
)
787 : __hashtable_base(__exk
, __h1
, __h2
, __h
, __eq
),
790 __hashtable_alloc(__node_alloc_type(__a
)),
794 _M_bucket_count
= _M_rehash_policy
._M_next_bkt(__bucket_hint
);
795 _M_buckets
= this->_M_allocate_buckets(_M_bucket_count
);
798 template<typename _Key
, typename _Value
,
799 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
800 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
802 template<typename _InputIterator
>
803 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
804 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
805 _Hashtable(_InputIterator __f
, _InputIterator __l
,
806 size_type __bucket_hint
,
807 const _H1
& __h1
, const _H2
& __h2
, const _Hash
& __h
,
808 const _Equal
& __eq
, const _ExtractKey
& __exk
,
809 const allocator_type
& __a
)
810 : __hashtable_base(__exk
, __h1
, __h2
, __h
, __eq
),
813 __hashtable_alloc(__node_alloc_type(__a
)),
817 auto __nb_elems
= __detail::__distance_fw(__f
, __l
);
819 _M_rehash_policy
._M_next_bkt(
820 std::max(_M_rehash_policy
._M_bkt_for_elements(__nb_elems
),
823 _M_buckets
= this->_M_allocate_buckets(_M_bucket_count
);
826 for (; __f
!= __l
; ++__f
)
832 _M_deallocate_buckets();
833 __throw_exception_again
;
837 template<typename _Key
, typename _Value
,
838 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
839 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
841 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
842 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>&
843 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
844 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::operator=(
845 const _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
846 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>& __ht
)
851 if (__node_alloc_traits::_S_propagate_on_copy_assign())
853 auto& __this_alloc
= this->_M_node_allocator();
854 auto& __that_alloc
= __ht
._M_node_allocator();
855 if (!__node_alloc_traits::_S_always_equal()
856 && __this_alloc
!= __that_alloc
)
858 // Replacement allocator cannot free existing storage.
859 this->_M_deallocate_nodes(_M_begin());
860 if (__builtin_expect(_M_bucket_count
!= 0, true))
861 _M_deallocate_buckets();
863 std::__alloc_on_copy(__this_alloc
, __that_alloc
);
864 __hashtable_base::operator=(__ht
);
865 _M_bucket_count
= __ht
._M_bucket_count
;
866 _M_element_count
= __ht
._M_element_count
;
867 _M_rehash_policy
= __ht
._M_rehash_policy
;
871 [this](const __node_type
* __n
)
872 { return this->_M_allocate_node(__n
->_M_v()); });
876 // _M_assign took care of deallocating all memory. Now we
877 // must make sure this instance remains in a usable state.
879 __throw_exception_again
;
883 std::__alloc_on_copy(__this_alloc
, __that_alloc
);
886 // Reuse allocated buckets and nodes.
887 __bucket_type
* __former_buckets
= nullptr;
888 std::size_t __former_bucket_count
= _M_bucket_count
;
889 const __rehash_state
& __former_state
= _M_rehash_policy
._M_state();
891 if (_M_bucket_count
!= __ht
._M_bucket_count
)
893 __former_buckets
= _M_buckets
;
894 _M_buckets
= this->_M_allocate_buckets(__ht
._M_bucket_count
);
895 _M_bucket_count
= __ht
._M_bucket_count
;
898 __builtin_memset(_M_buckets
, 0,
899 _M_bucket_count
* sizeof(__bucket_type
));
903 __hashtable_base::operator=(__ht
);
904 _M_element_count
= __ht
._M_element_count
;
905 _M_rehash_policy
= __ht
._M_rehash_policy
;
906 __reuse_or_alloc_node_type
__roan(_M_begin(), *this);
907 _M_before_begin
._M_nxt
= nullptr;
909 [&__roan
](const __node_type
* __n
)
910 { return __roan(__n
->_M_v()); });
911 if (__former_buckets
)
912 this->_M_deallocate_buckets(__former_buckets
,
913 __former_bucket_count
);
917 if (__former_buckets
)
919 // Restore previous buckets.
920 _M_deallocate_buckets();
921 _M_rehash_policy
._M_reset(__former_state
);
922 _M_buckets
= __former_buckets
;
923 _M_bucket_count
= __former_bucket_count
;
925 __builtin_memset(_M_buckets
, 0,
926 _M_bucket_count
* sizeof(__bucket_type
));
927 __throw_exception_again
;
932 template<typename _Key
, typename _Value
,
933 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
934 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
936 template<typename _NodeGenerator
>
938 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
939 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
940 _M_assign(const _Hashtable
& __ht
, const _NodeGenerator
& __node_gen
)
942 __bucket_type
* __buckets
= nullptr;
944 _M_buckets
= __buckets
= this->_M_allocate_buckets(_M_bucket_count
);
948 if (!__ht
._M_before_begin
._M_nxt
)
951 // First deal with the special first node pointed to by
953 __node_type
* __ht_n
= __ht
._M_begin();
954 __node_type
* __this_n
= __node_gen(__ht_n
);
955 this->_M_copy_code(__this_n
, __ht_n
);
956 _M_before_begin
._M_nxt
= __this_n
;
957 _M_buckets
[_M_bucket_index(__this_n
)] = &_M_before_begin
;
959 // Then deal with other nodes.
960 __node_base
* __prev_n
= __this_n
;
961 for (__ht_n
= __ht_n
->_M_next(); __ht_n
; __ht_n
= __ht_n
->_M_next())
963 __this_n
= __node_gen(__ht_n
);
964 __prev_n
->_M_nxt
= __this_n
;
965 this->_M_copy_code(__this_n
, __ht_n
);
966 size_type __bkt
= _M_bucket_index(__this_n
);
967 if (!_M_buckets
[__bkt
])
968 _M_buckets
[__bkt
] = __prev_n
;
976 _M_deallocate_buckets();
977 __throw_exception_again
;
981 template<typename _Key
, typename _Value
,
982 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
983 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
986 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
987 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
990 _M_rehash_policy
._M_reset();
992 _M_buckets
= nullptr;
993 _M_before_begin
._M_nxt
= nullptr;
994 _M_element_count
= 0;
997 template<typename _Key
, typename _Value
,
998 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
999 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1002 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1003 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1004 _M_move_assign(_Hashtable
&& __ht
, std::true_type
)
1006 this->_M_deallocate_nodes(_M_begin());
1007 if (__builtin_expect(_M_bucket_count
!= 0, true))
1008 _M_deallocate_buckets();
1010 __hashtable_base::operator=(std::move(__ht
));
1011 _M_rehash_policy
= __ht
._M_rehash_policy
;
1012 _M_buckets
= __ht
._M_buckets
;
1013 _M_bucket_count
= __ht
._M_bucket_count
;
1014 _M_before_begin
._M_nxt
= __ht
._M_before_begin
._M_nxt
;
1015 _M_element_count
= __ht
._M_element_count
;
1016 std::__alloc_on_move(this->_M_node_allocator(), __ht
._M_node_allocator());
1018 // Fix buckets containing the _M_before_begin pointers that can't be
1021 _M_buckets
[_M_bucket_index(_M_begin())] = &_M_before_begin
;
1025 template<typename _Key
, typename _Value
,
1026 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1027 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1030 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1031 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1032 _M_move_assign(_Hashtable
&& __ht
, std::false_type
)
1034 if (__ht
._M_node_allocator() == this->_M_node_allocator())
1035 _M_move_assign(std::move(__ht
), std::true_type());
1038 // Can't move memory, move elements then.
1039 __bucket_type
* __former_buckets
= nullptr;
1040 size_type __former_bucket_count
= _M_bucket_count
;
1041 const __rehash_state
& __former_state
= _M_rehash_policy
._M_state();
1043 if (_M_bucket_count
!= __ht
._M_bucket_count
)
1045 __former_buckets
= _M_buckets
;
1046 _M_buckets
= this->_M_allocate_buckets(__ht
._M_bucket_count
);
1047 _M_bucket_count
= __ht
._M_bucket_count
;
1050 __builtin_memset(_M_buckets
, 0,
1051 _M_bucket_count
* sizeof(__bucket_type
));
1055 __hashtable_base::operator=(std::move(__ht
));
1056 _M_element_count
= __ht
._M_element_count
;
1057 _M_rehash_policy
= __ht
._M_rehash_policy
;
1058 __reuse_or_alloc_node_type
__roan(_M_begin(), *this);
1059 _M_before_begin
._M_nxt
= nullptr;
1061 [&__roan
](__node_type
* __n
)
1062 { return __roan(std::move_if_noexcept(__n
->_M_v())); });
1067 if (__former_buckets
)
1069 _M_deallocate_buckets();
1070 _M_rehash_policy
._M_reset(__former_state
);
1071 _M_buckets
= __former_buckets
;
1072 _M_bucket_count
= __former_bucket_count
;
1074 __builtin_memset(_M_buckets
, 0,
1075 _M_bucket_count
* sizeof(__bucket_type
));
1076 __throw_exception_again
;
1081 template<typename _Key
, typename _Value
,
1082 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1083 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1085 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1086 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1087 _Hashtable(const _Hashtable
& __ht
)
1088 : __hashtable_base(__ht
),
1090 __rehash_base(__ht
),
1092 __node_alloc_traits::_S_select_on_copy(__ht
._M_node_allocator())),
1094 _M_bucket_count(__ht
._M_bucket_count
),
1095 _M_element_count(__ht
._M_element_count
),
1096 _M_rehash_policy(__ht
._M_rehash_policy
)
1099 [this](const __node_type
* __n
)
1100 { return this->_M_allocate_node(__n
->_M_v()); });
1103 template<typename _Key
, typename _Value
,
1104 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1105 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1107 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1108 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1109 _Hashtable(_Hashtable
&& __ht
) noexcept
1110 : __hashtable_base(__ht
),
1112 __rehash_base(__ht
),
1113 __hashtable_alloc(std::move(__ht
._M_base_alloc())),
1114 _M_buckets(__ht
._M_buckets
),
1115 _M_bucket_count(__ht
._M_bucket_count
),
1116 _M_before_begin(__ht
._M_before_begin
._M_nxt
),
1117 _M_element_count(__ht
._M_element_count
),
1118 _M_rehash_policy(__ht
._M_rehash_policy
)
1120 // Update, if necessary, bucket pointing to before begin that hasn't
1123 _M_buckets
[_M_bucket_index(_M_begin())] = &_M_before_begin
;
1127 template<typename _Key
, typename _Value
,
1128 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1129 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1131 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1132 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1133 _Hashtable(const _Hashtable
& __ht
, const allocator_type
& __a
)
1134 : __hashtable_base(__ht
),
1136 __rehash_base(__ht
),
1137 __hashtable_alloc(__node_alloc_type(__a
)),
1139 _M_bucket_count(__ht
._M_bucket_count
),
1140 _M_element_count(__ht
._M_element_count
),
1141 _M_rehash_policy(__ht
._M_rehash_policy
)
1144 [this](const __node_type
* __n
)
1145 { return this->_M_allocate_node(__n
->_M_v()); });
1148 template<typename _Key
, typename _Value
,
1149 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1150 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1152 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1153 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1154 _Hashtable(_Hashtable
&& __ht
, const allocator_type
& __a
)
1155 : __hashtable_base(__ht
),
1157 __rehash_base(__ht
),
1158 __hashtable_alloc(__node_alloc_type(__a
)),
1160 _M_bucket_count(__ht
._M_bucket_count
),
1161 _M_element_count(__ht
._M_element_count
),
1162 _M_rehash_policy(__ht
._M_rehash_policy
)
1164 if (__ht
._M_node_allocator() == this->_M_node_allocator())
1166 _M_buckets
= __ht
._M_buckets
;
1167 _M_before_begin
._M_nxt
= __ht
._M_before_begin
._M_nxt
;
1168 // Update, if necessary, bucket pointing to before begin that hasn't
1171 _M_buckets
[_M_bucket_index(_M_begin())] = &_M_before_begin
;
1177 [this](__node_type
* __n
)
1179 return this->_M_allocate_node(
1180 std::move_if_noexcept(__n
->_M_v()));
1186 template<typename _Key
, typename _Value
,
1187 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1188 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1190 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1191 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1192 ~_Hashtable() noexcept
1196 _M_deallocate_buckets();
1199 template<typename _Key
, typename _Value
,
1200 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1201 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1204 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1205 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1206 swap(_Hashtable
& __x
)
1207 noexcept(__node_alloc_traits::_S_nothrow_swap())
1209 // The only base class with member variables is hash_code_base.
1210 // We define _Hash_code_base::_M_swap because different
1211 // specializations have different members.
1214 std::__alloc_on_swap(this->_M_node_allocator(), __x
._M_node_allocator());
1215 std::swap(_M_rehash_policy
, __x
._M_rehash_policy
);
1216 std::swap(_M_buckets
, __x
._M_buckets
);
1217 std::swap(_M_bucket_count
, __x
._M_bucket_count
);
1218 std::swap(_M_before_begin
._M_nxt
, __x
._M_before_begin
._M_nxt
);
1219 std::swap(_M_element_count
, __x
._M_element_count
);
1221 // Fix buckets containing the _M_before_begin pointers that can't be
1224 _M_buckets
[_M_bucket_index(_M_begin())] = &_M_before_begin
;
1226 __x
._M_buckets
[__x
._M_bucket_index(__x
._M_begin())]
1227 = &__x
._M_before_begin
;
1230 template<typename _Key
, typename _Value
,
1231 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1232 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1235 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1236 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1237 __rehash_policy(const _RehashPolicy
& __pol
)
1239 size_type __n_bkt
= __pol
._M_bkt_for_elements(_M_element_count
);
1240 __n_bkt
= __pol
._M_next_bkt(__n_bkt
);
1241 if (__n_bkt
!= _M_bucket_count
)
1242 _M_rehash(__n_bkt
, _M_rehash_policy
._M_state());
1243 _M_rehash_policy
= __pol
;
1246 template<typename _Key
, typename _Value
,
1247 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1248 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1250 typename _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1251 _H1
, _H2
, _Hash
, _RehashPolicy
,
1253 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1254 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1255 find(const key_type
& __k
)
1257 if (__builtin_expect(_M_bucket_count
== 0, false))
1260 __hash_code __code
= this->_M_hash_code(__k
);
1261 std::size_t __n
= _M_bucket_index(__k
, __code
);
1262 __node_type
* __p
= _M_find_node(__n
, __k
, __code
);
1263 return __p
? iterator(__p
) : end();
1266 template<typename _Key
, typename _Value
,
1267 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1268 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1270 typename _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1271 _H1
, _H2
, _Hash
, _RehashPolicy
,
1272 _Traits
>::const_iterator
1273 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1274 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1275 find(const key_type
& __k
) const
1277 if (__builtin_expect(_M_bucket_count
== 0, false))
1280 __hash_code __code
= this->_M_hash_code(__k
);
1281 std::size_t __n
= _M_bucket_index(__k
, __code
);
1282 __node_type
* __p
= _M_find_node(__n
, __k
, __code
);
1283 return __p
? const_iterator(__p
) : end();
1286 template<typename _Key
, typename _Value
,
1287 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1288 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1290 typename _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1291 _H1
, _H2
, _Hash
, _RehashPolicy
,
1293 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1294 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1295 count(const key_type
& __k
) const
1297 if (__builtin_expect(_M_bucket_count
== 0, false))
1300 __hash_code __code
= this->_M_hash_code(__k
);
1301 std::size_t __n
= _M_bucket_index(__k
, __code
);
1302 __node_type
* __p
= _M_bucket_begin(__n
);
1306 std::size_t __result
= 0;
1307 for (;; __p
= __p
->_M_next())
1309 if (this->_M_equals(__k
, __code
, __p
))
1312 // All equivalent values are next to each other, if we
1313 // found a non-equivalent value after an equivalent one it
1314 // means that we won't find any more equivalent values.
1316 if (!__p
->_M_nxt
|| _M_bucket_index(__p
->_M_next()) != __n
)
1322 template<typename _Key
, typename _Value
,
1323 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1324 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1326 std::pair
<typename _Hashtable
<_Key
, _Value
, _Alloc
,
1327 _ExtractKey
, _Equal
, _H1
,
1328 _H2
, _Hash
, _RehashPolicy
,
1330 typename _Hashtable
<_Key
, _Value
, _Alloc
,
1331 _ExtractKey
, _Equal
, _H1
,
1332 _H2
, _Hash
, _RehashPolicy
,
1334 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1335 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1336 equal_range(const key_type
& __k
)
1338 if (__builtin_expect(_M_bucket_count
== 0, false))
1339 return std::make_pair(end(), end());
1341 __hash_code __code
= this->_M_hash_code(__k
);
1342 std::size_t __n
= _M_bucket_index(__k
, __code
);
1343 __node_type
* __p
= _M_find_node(__n
, __k
, __code
);
1347 __node_type
* __p1
= __p
->_M_next();
1348 while (__p1
&& _M_bucket_index(__p1
) == __n
1349 && this->_M_equals(__k
, __code
, __p1
))
1350 __p1
= __p1
->_M_next();
1352 return std::make_pair(iterator(__p
), iterator(__p1
));
1355 return std::make_pair(end(), end());
1358 template<typename _Key
, typename _Value
,
1359 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1360 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1362 std::pair
<typename _Hashtable
<_Key
, _Value
, _Alloc
,
1363 _ExtractKey
, _Equal
, _H1
,
1364 _H2
, _Hash
, _RehashPolicy
,
1365 _Traits
>::const_iterator
,
1366 typename _Hashtable
<_Key
, _Value
, _Alloc
,
1367 _ExtractKey
, _Equal
, _H1
,
1368 _H2
, _Hash
, _RehashPolicy
,
1369 _Traits
>::const_iterator
>
1370 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1371 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1372 equal_range(const key_type
& __k
) const
1374 if (__builtin_expect(_M_bucket_count
== 0, false))
1375 return std::make_pair(end(), end());
1377 __hash_code __code
= this->_M_hash_code(__k
);
1378 std::size_t __n
= _M_bucket_index(__k
, __code
);
1379 __node_type
* __p
= _M_find_node(__n
, __k
, __code
);
1383 __node_type
* __p1
= __p
->_M_next();
1384 while (__p1
&& _M_bucket_index(__p1
) == __n
1385 && this->_M_equals(__k
, __code
, __p1
))
1386 __p1
= __p1
->_M_next();
1388 return std::make_pair(const_iterator(__p
), const_iterator(__p1
));
1391 return std::make_pair(end(), end());
1394 // Find the node whose key compares equal to k in the bucket n.
1395 // Return nullptr if no node is found.
1396 template<typename _Key
, typename _Value
,
1397 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1398 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1400 typename _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
,
1401 _Equal
, _H1
, _H2
, _Hash
, _RehashPolicy
,
1402 _Traits
>::__node_base
*
1403 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1404 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1405 _M_find_before_node(size_type __n
, const key_type
& __k
,
1406 __hash_code __code
) const
1408 __node_base
* __prev_p
= _M_buckets
[__n
];
1412 for (__node_type
* __p
= static_cast<__node_type
*>(__prev_p
->_M_nxt
);;
1413 __p
= __p
->_M_next())
1415 if (this->_M_equals(__k
, __code
, __p
))
1418 if (!__p
->_M_nxt
|| _M_bucket_index(__p
->_M_next()) != __n
)
1425 template<typename _Key
, typename _Value
,
1426 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1427 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1430 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1431 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1432 _M_insert_bucket_begin(size_type __bkt
, __node_type
* __node
)
1434 if (_M_buckets
[__bkt
])
1436 // Bucket is not empty, we just need to insert the new node
1437 // after the bucket before begin.
1438 __node
->_M_nxt
= _M_buckets
[__bkt
]->_M_nxt
;
1439 _M_buckets
[__bkt
]->_M_nxt
= __node
;
1443 // The bucket is empty, the new node is inserted at the
1444 // beginning of the singly-linked list and the bucket will
1445 // contain _M_before_begin pointer.
1446 __node
->_M_nxt
= _M_before_begin
._M_nxt
;
1447 _M_before_begin
._M_nxt
= __node
;
1449 // We must update former begin bucket that is pointing to
1451 _M_buckets
[_M_bucket_index(__node
->_M_next())] = __node
;
1452 _M_buckets
[__bkt
] = &_M_before_begin
;
1456 template<typename _Key
, typename _Value
,
1457 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1458 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1461 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1462 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1463 _M_remove_bucket_begin(size_type __bkt
, __node_type
* __next
,
1464 size_type __next_bkt
)
1466 if (!__next
|| __next_bkt
!= __bkt
)
1468 // Bucket is now empty
1469 // First update next bucket if any
1471 _M_buckets
[__next_bkt
] = _M_buckets
[__bkt
];
1473 // Second update before begin node if necessary
1474 if (&_M_before_begin
== _M_buckets
[__bkt
])
1475 _M_before_begin
._M_nxt
= __next
;
1476 _M_buckets
[__bkt
] = nullptr;
1480 template<typename _Key
, typename _Value
,
1481 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1482 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1484 typename _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
,
1485 _Equal
, _H1
, _H2
, _Hash
, _RehashPolicy
,
1486 _Traits
>::__node_base
*
1487 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1488 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1489 _M_get_previous_node(size_type __bkt
, __node_base
* __n
)
1491 __node_base
* __prev_n
= _M_buckets
[__bkt
];
1492 while (__prev_n
->_M_nxt
!= __n
)
1493 __prev_n
= __prev_n
->_M_nxt
;
1497 template<typename _Key
, typename _Value
,
1498 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1499 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1501 template<typename
... _Args
>
1502 std::pair
<typename _Hashtable
<_Key
, _Value
, _Alloc
,
1503 _ExtractKey
, _Equal
, _H1
,
1504 _H2
, _Hash
, _RehashPolicy
,
1505 _Traits
>::iterator
, bool>
1506 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1507 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1508 _M_emplace(std::true_type
, _Args
&&... __args
)
1510 // First build the node to get access to the hash code
1511 __node_type
* __node
= this->_M_allocate_node(std::forward
<_Args
>(__args
)...);
1512 const key_type
& __k
= this->_M_extract()(__node
->_M_v());
1516 __code
= this->_M_hash_code(__k
);
1520 this->_M_deallocate_node(__node
);
1521 __throw_exception_again
;
1524 size_type __bkt
= _M_bucket_index(__k
, __code
);
1525 if (__node_type
* __p
= _M_find_node(__bkt
, __k
, __code
))
1527 // There is already an equivalent node, no insertion
1528 this->_M_deallocate_node(__node
);
1529 return std::make_pair(iterator(__p
), false);
1533 return std::make_pair(_M_insert_unique_node(__bkt
, __code
, __node
),
1537 template<typename _Key
, typename _Value
,
1538 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1539 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1541 template<typename
... _Args
>
1542 typename _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1543 _H1
, _H2
, _Hash
, _RehashPolicy
,
1545 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1546 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1547 _M_emplace(const_iterator __hint
, std::false_type
, _Args
&&... __args
)
1549 // First build the node to get its hash code.
1550 __node_type
* __node
=
1551 this->_M_allocate_node(std::forward
<_Args
>(__args
)...);
1556 __code
= this->_M_hash_code(this->_M_extract()(__node
->_M_v()));
1560 this->_M_deallocate_node(__node
);
1561 __throw_exception_again
;
1564 return _M_insert_multi_node(__hint
._M_cur
, __code
, __node
);
1567 template<typename _Key
, typename _Value
,
1568 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1569 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1571 typename _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1572 _H1
, _H2
, _Hash
, _RehashPolicy
,
1574 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1575 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1576 _M_insert_unique_node(size_type __bkt
, __hash_code __code
,
1577 __node_type
* __node
)
1579 const __rehash_state
& __saved_state
= _M_rehash_policy
._M_state();
1580 std::pair
<bool, std::size_t> __do_rehash
1581 = _M_rehash_policy
._M_need_rehash(_M_bucket_count
, _M_element_count
, 1);
1585 if (__do_rehash
.first
)
1587 _M_rehash(__do_rehash
.second
, __saved_state
);
1588 __bkt
= _M_bucket_index(this->_M_extract()(__node
->_M_v()), __code
);
1591 this->_M_store_code(__node
, __code
);
1593 // Always insert at the beginning of the bucket.
1594 _M_insert_bucket_begin(__bkt
, __node
);
1596 return iterator(__node
);
1600 this->_M_deallocate_node(__node
);
1601 __throw_exception_again
;
1605 // Insert node, in bucket bkt if no rehash (assumes no element with its key
1606 // already present). Take ownership of the node, deallocate it on exception.
1607 template<typename _Key
, typename _Value
,
1608 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1609 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1611 typename _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1612 _H1
, _H2
, _Hash
, _RehashPolicy
,
1614 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1615 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1616 _M_insert_multi_node(__node_type
* __hint
, __hash_code __code
,
1617 __node_type
* __node
)
1619 const __rehash_state
& __saved_state
= _M_rehash_policy
._M_state();
1620 std::pair
<bool, std::size_t> __do_rehash
1621 = _M_rehash_policy
._M_need_rehash(_M_bucket_count
, _M_element_count
, 1);
1625 if (__do_rehash
.first
)
1626 _M_rehash(__do_rehash
.second
, __saved_state
);
1628 this->_M_store_code(__node
, __code
);
1629 const key_type
& __k
= this->_M_extract()(__node
->_M_v());
1630 size_type __bkt
= _M_bucket_index(__k
, __code
);
1632 // Find the node before an equivalent one or use hint if it exists and
1633 // if it is equivalent.
1635 = __builtin_expect(__hint
!= nullptr, false)
1636 && this->_M_equals(__k
, __code
, __hint
)
1638 : _M_find_before_node(__bkt
, __k
, __code
);
1641 // Insert after the node before the equivalent one.
1642 __node
->_M_nxt
= __prev
->_M_nxt
;
1643 __prev
->_M_nxt
= __node
;
1644 if (__builtin_expect(__prev
== __hint
, false))
1645 // hint might be the last bucket node, in this case we need to
1646 // update next bucket.
1648 && !this->_M_equals(__k
, __code
, __node
->_M_next()))
1650 size_type __next_bkt
= _M_bucket_index(__node
->_M_next());
1651 if (__next_bkt
!= __bkt
)
1652 _M_buckets
[__next_bkt
] = __node
;
1656 // The inserted node has no equivalent in the
1657 // hashtable. We must insert the new node at the
1658 // beginning of the bucket to preserve equivalent
1659 // elements' relative positions.
1660 _M_insert_bucket_begin(__bkt
, __node
);
1662 return iterator(__node
);
1666 this->_M_deallocate_node(__node
);
1667 __throw_exception_again
;
1671 // Insert v if no element with its key is already present.
1672 template<typename _Key
, typename _Value
,
1673 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1674 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1676 template<typename _Arg
, typename _NodeGenerator
>
1677 std::pair
<typename _Hashtable
<_Key
, _Value
, _Alloc
,
1678 _ExtractKey
, _Equal
, _H1
,
1679 _H2
, _Hash
, _RehashPolicy
,
1680 _Traits
>::iterator
, bool>
1681 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1682 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1683 _M_insert(_Arg
&& __v
, const _NodeGenerator
& __node_gen
, std::true_type
)
1685 const key_type
& __k
= this->_M_extract()(__v
);
1686 __hash_code __code
= this->_M_hash_code(__k
);
1687 size_type __bkt
= _M_bucket_index(__k
, __code
);
1689 __node_type
* __n
= _M_find_node(__bkt
, __k
, __code
);
1691 return std::make_pair(iterator(__n
), false);
1693 __n
= __node_gen(std::forward
<_Arg
>(__v
));
1694 return std::make_pair(_M_insert_unique_node(__bkt
, __code
, __n
), true);
1697 // Insert v unconditionally.
1698 template<typename _Key
, typename _Value
,
1699 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1700 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1702 template<typename _Arg
, typename _NodeGenerator
>
1703 typename _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1704 _H1
, _H2
, _Hash
, _RehashPolicy
,
1706 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1707 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1708 _M_insert(const_iterator __hint
, _Arg
&& __v
,
1709 const _NodeGenerator
& __node_gen
,
1712 // First compute the hash code so that we don't do anything if it
1714 __hash_code __code
= this->_M_hash_code(this->_M_extract()(__v
));
1716 // Second allocate new node so that we don't rehash if it throws.
1717 __node_type
* __node
= __node_gen(std::forward
<_Arg
>(__v
));
1719 return _M_insert_multi_node(__hint
._M_cur
, __code
, __node
);
1722 template<typename _Key
, typename _Value
,
1723 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1724 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1726 typename _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1727 _H1
, _H2
, _Hash
, _RehashPolicy
,
1729 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1730 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1731 erase(const_iterator __it
)
1733 __node_type
* __n
= __it
._M_cur
;
1734 std::size_t __bkt
= _M_bucket_index(__n
);
1736 // Look for previous node to unlink it from the erased one, this
1737 // is why we need buckets to contain the before begin to make
1738 // this search fast.
1739 __node_base
* __prev_n
= _M_get_previous_node(__bkt
, __n
);
1740 return _M_erase(__bkt
, __prev_n
, __n
);
1743 template<typename _Key
, typename _Value
,
1744 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1745 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1747 typename _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1748 _H1
, _H2
, _Hash
, _RehashPolicy
,
1750 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1751 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1752 _M_erase(size_type __bkt
, __node_base
* __prev_n
, __node_type
* __n
)
1754 if (__prev_n
== _M_buckets
[__bkt
])
1755 _M_remove_bucket_begin(__bkt
, __n
->_M_next(),
1756 __n
->_M_nxt
? _M_bucket_index(__n
->_M_next()) : 0);
1757 else if (__n
->_M_nxt
)
1759 size_type __next_bkt
= _M_bucket_index(__n
->_M_next());
1760 if (__next_bkt
!= __bkt
)
1761 _M_buckets
[__next_bkt
] = __prev_n
;
1764 __prev_n
->_M_nxt
= __n
->_M_nxt
;
1765 iterator
__result(__n
->_M_next());
1766 this->_M_deallocate_node(__n
);
1772 template<typename _Key
, typename _Value
,
1773 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1774 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1776 typename _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1777 _H1
, _H2
, _Hash
, _RehashPolicy
,
1779 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1780 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1781 _M_erase(std::true_type
, const key_type
& __k
)
1783 __hash_code __code
= this->_M_hash_code(__k
);
1784 std::size_t __bkt
= _M_bucket_index(__k
, __code
);
1786 // Look for the node before the first matching node.
1787 __node_base
* __prev_n
= _M_find_before_node(__bkt
, __k
, __code
);
1791 // We found a matching node, erase it.
1792 __node_type
* __n
= static_cast<__node_type
*>(__prev_n
->_M_nxt
);
1793 _M_erase(__bkt
, __prev_n
, __n
);
1797 template<typename _Key
, typename _Value
,
1798 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1799 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1801 typename _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1802 _H1
, _H2
, _Hash
, _RehashPolicy
,
1804 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1805 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1806 _M_erase(std::false_type
, const key_type
& __k
)
1808 __hash_code __code
= this->_M_hash_code(__k
);
1809 std::size_t __bkt
= _M_bucket_index(__k
, __code
);
1811 // Look for the node before the first matching node.
1812 __node_base
* __prev_n
= _M_find_before_node(__bkt
, __k
, __code
);
1816 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1817 // 526. Is it undefined if a function in the standard changes
1819 // We use one loop to find all matching nodes and another to deallocate
1820 // them so that the key stays valid during the first loop. It might be
1821 // invalidated indirectly when destroying nodes.
1822 __node_type
* __n
= static_cast<__node_type
*>(__prev_n
->_M_nxt
);
1823 __node_type
* __n_last
= __n
;
1824 std::size_t __n_last_bkt
= __bkt
;
1827 __n_last
= __n_last
->_M_next();
1830 __n_last_bkt
= _M_bucket_index(__n_last
);
1832 while (__n_last_bkt
== __bkt
&& this->_M_equals(__k
, __code
, __n_last
));
1834 // Deallocate nodes.
1835 size_type __result
= 0;
1838 __node_type
* __p
= __n
->_M_next();
1839 this->_M_deallocate_node(__n
);
1844 while (__n
!= __n_last
);
1846 if (__prev_n
== _M_buckets
[__bkt
])
1847 _M_remove_bucket_begin(__bkt
, __n_last
, __n_last_bkt
);
1848 else if (__n_last
&& __n_last_bkt
!= __bkt
)
1849 _M_buckets
[__n_last_bkt
] = __prev_n
;
1850 __prev_n
->_M_nxt
= __n_last
;
1854 template<typename _Key
, typename _Value
,
1855 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1856 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1858 typename _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1859 _H1
, _H2
, _Hash
, _RehashPolicy
,
1861 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1862 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1863 erase(const_iterator __first
, const_iterator __last
)
1865 __node_type
* __n
= __first
._M_cur
;
1866 __node_type
* __last_n
= __last
._M_cur
;
1867 if (__n
== __last_n
)
1868 return iterator(__n
);
1870 std::size_t __bkt
= _M_bucket_index(__n
);
1872 __node_base
* __prev_n
= _M_get_previous_node(__bkt
, __n
);
1873 bool __is_bucket_begin
= __n
== _M_bucket_begin(__bkt
);
1874 std::size_t __n_bkt
= __bkt
;
1879 __node_type
* __tmp
= __n
;
1880 __n
= __n
->_M_next();
1881 this->_M_deallocate_node(__tmp
);
1885 __n_bkt
= _M_bucket_index(__n
);
1887 while (__n
!= __last_n
&& __n_bkt
== __bkt
);
1888 if (__is_bucket_begin
)
1889 _M_remove_bucket_begin(__bkt
, __n
, __n_bkt
);
1890 if (__n
== __last_n
)
1892 __is_bucket_begin
= true;
1896 if (__n
&& (__n_bkt
!= __bkt
|| __is_bucket_begin
))
1897 _M_buckets
[__n_bkt
] = __prev_n
;
1898 __prev_n
->_M_nxt
= __n
;
1899 return iterator(__n
);
1902 template<typename _Key
, typename _Value
,
1903 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1904 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1907 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1908 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1911 this->_M_deallocate_nodes(_M_begin());
1912 __builtin_memset(_M_buckets
, 0, _M_bucket_count
* sizeof(__bucket_type
));
1913 _M_element_count
= 0;
1914 _M_before_begin
._M_nxt
= nullptr;
1917 template<typename _Key
, typename _Value
,
1918 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1919 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1922 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1923 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1924 rehash(size_type __n
)
1926 const __rehash_state
& __saved_state
= _M_rehash_policy
._M_state();
1927 std::size_t __buckets
1928 = std::max(_M_rehash_policy
._M_bkt_for_elements(_M_element_count
+ 1),
1930 __buckets
= _M_rehash_policy
._M_next_bkt(__buckets
);
1932 if (__buckets
!= _M_bucket_count
)
1933 _M_rehash(__buckets
, __saved_state
);
1935 // No rehash, restore previous state to keep a consistent state.
1936 _M_rehash_policy
._M_reset(__saved_state
);
1939 template<typename _Key
, typename _Value
,
1940 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1941 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1944 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1945 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1946 _M_rehash(size_type __n
, const __rehash_state
& __state
)
1950 _M_rehash_aux(__n
, __unique_keys());
1954 // A failure here means that buckets allocation failed. We only
1955 // have to restore hash policy previous state.
1956 _M_rehash_policy
._M_reset(__state
);
1957 __throw_exception_again
;
1961 // Rehash when there is no equivalent elements.
1962 template<typename _Key
, typename _Value
,
1963 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
1964 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
1967 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
1968 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
1969 _M_rehash_aux(size_type __n
, std::true_type
)
1971 __bucket_type
* __new_buckets
= this->_M_allocate_buckets(__n
);
1972 __node_type
* __p
= _M_begin();
1973 _M_before_begin
._M_nxt
= nullptr;
1974 std::size_t __bbegin_bkt
= 0;
1977 __node_type
* __next
= __p
->_M_next();
1978 std::size_t __bkt
= __hash_code_base::_M_bucket_index(__p
, __n
);
1979 if (!__new_buckets
[__bkt
])
1981 __p
->_M_nxt
= _M_before_begin
._M_nxt
;
1982 _M_before_begin
._M_nxt
= __p
;
1983 __new_buckets
[__bkt
] = &_M_before_begin
;
1985 __new_buckets
[__bbegin_bkt
] = __p
;
1986 __bbegin_bkt
= __bkt
;
1990 __p
->_M_nxt
= __new_buckets
[__bkt
]->_M_nxt
;
1991 __new_buckets
[__bkt
]->_M_nxt
= __p
;
1996 if (__builtin_expect(_M_bucket_count
!= 0, true))
1997 _M_deallocate_buckets();
1998 _M_bucket_count
= __n
;
1999 _M_buckets
= __new_buckets
;
2002 // Rehash when there can be equivalent elements, preserve their relative
2004 template<typename _Key
, typename _Value
,
2005 typename _Alloc
, typename _ExtractKey
, typename _Equal
,
2006 typename _H1
, typename _H2
, typename _Hash
, typename _RehashPolicy
,
2009 _Hashtable
<_Key
, _Value
, _Alloc
, _ExtractKey
, _Equal
,
2010 _H1
, _H2
, _Hash
, _RehashPolicy
, _Traits
>::
2011 _M_rehash_aux(size_type __n
, std::false_type
)
2013 __bucket_type
* __new_buckets
= this->_M_allocate_buckets(__n
);
2015 __node_type
* __p
= _M_begin();
2016 _M_before_begin
._M_nxt
= nullptr;
2017 std::size_t __bbegin_bkt
= 0;
2018 std::size_t __prev_bkt
= 0;
2019 __node_type
* __prev_p
= nullptr;
2020 bool __check_bucket
= false;
2024 __node_type
* __next
= __p
->_M_next();
2025 std::size_t __bkt
= __hash_code_base::_M_bucket_index(__p
, __n
);
2027 if (__prev_p
&& __prev_bkt
== __bkt
)
2029 // Previous insert was already in this bucket, we insert after
2030 // the previously inserted one to preserve equivalent elements
2032 __p
->_M_nxt
= __prev_p
->_M_nxt
;
2033 __prev_p
->_M_nxt
= __p
;
2035 // Inserting after a node in a bucket require to check that we
2036 // haven't change the bucket last node, in this case next
2037 // bucket containing its before begin node must be updated. We
2038 // schedule a check as soon as we move out of the sequence of
2039 // equivalent nodes to limit the number of checks.
2040 __check_bucket
= true;
2046 // Check if we shall update the next bucket because of
2047 // insertions into __prev_bkt bucket.
2048 if (__prev_p
->_M_nxt
)
2050 std::size_t __next_bkt
2051 = __hash_code_base::_M_bucket_index(__prev_p
->_M_next(),
2053 if (__next_bkt
!= __prev_bkt
)
2054 __new_buckets
[__next_bkt
] = __prev_p
;
2056 __check_bucket
= false;
2059 if (!__new_buckets
[__bkt
])
2061 __p
->_M_nxt
= _M_before_begin
._M_nxt
;
2062 _M_before_begin
._M_nxt
= __p
;
2063 __new_buckets
[__bkt
] = &_M_before_begin
;
2065 __new_buckets
[__bbegin_bkt
] = __p
;
2066 __bbegin_bkt
= __bkt
;
2070 __p
->_M_nxt
= __new_buckets
[__bkt
]->_M_nxt
;
2071 __new_buckets
[__bkt
]->_M_nxt
= __p
;
2079 if (__check_bucket
&& __prev_p
->_M_nxt
)
2081 std::size_t __next_bkt
2082 = __hash_code_base::_M_bucket_index(__prev_p
->_M_next(), __n
);
2083 if (__next_bkt
!= __prev_bkt
)
2084 __new_buckets
[__next_bkt
] = __prev_p
;
2087 if (__builtin_expect(_M_bucket_count
!= 0, true))
2088 _M_deallocate_buckets();
2089 _M_bucket_count
= __n
;
2090 _M_buckets
= __new_buckets
;
2093 _GLIBCXX_END_NAMESPACE_VERSION
2096 #endif // _HASHTABLE_H