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1 : // hashtable.h header -*- C++ -*-
2 :
3 : // Copyright (C) 2007-2017 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.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}
28 : */
29 :
30 : #ifndef _HASHTABLE_H
31 : #define _HASHTABLE_H 1
32 :
33 : #pragma GCC system_header
34 :
35 : #include <bits/hashtable_policy.h>
36 : #if __cplusplus > 201402L
37 : # include <bits/node_handle.h>
38 : #endif
39 :
40 : namespace std _GLIBCXX_VISIBILITY(default)
41 : {
42 : _GLIBCXX_BEGIN_NAMESPACE_VERSION
43 :
44 : template<typename _Tp, typename _Hash>
45 : using __cache_default
46 : = __not_<__and_<// Do not cache for fast hasher.
47 : __is_fast_hash<_Hash>,
48 : // Mandatory to have erase not throwing.
49 : __detail::__is_noexcept_hash<_Tp, _Hash>>>;
50 :
51 : /**
52 : * Primary class template _Hashtable.
53 : *
54 : * @ingroup hashtable-detail
55 : *
56 : * @tparam _Value CopyConstructible type.
57 : *
58 : * @tparam _Key CopyConstructible type.
59 : *
60 : * @tparam _Alloc An allocator type
61 : * ([lib.allocator.requirements]) whose _Alloc::value_type is
62 : * _Value. As a conforming extension, we allow for
63 : * _Alloc::value_type != _Value.
64 : *
65 : * @tparam _ExtractKey Function object that takes an object of type
66 : * _Value and returns a value of type _Key.
67 : *
68 : * @tparam _Equal Function object that takes two objects of type k
69 : * and returns a bool-like value that is true if the two objects
70 : * are considered equal.
71 : *
72 : * @tparam _H1 The hash function. A unary function object with
73 : * argument type _Key and result type size_t. Return values should
74 : * be distributed over the entire range [0, numeric_limits<size_t>:::max()].
75 : *
76 : * @tparam _H2 The range-hashing function (in the terminology of
77 : * Tavori and Dreizin). A binary function object whose argument
78 : * types and result type are all size_t. Given arguments r and N,
79 : * the return value is in the range [0, N).
80 : *
81 : * @tparam _Hash The ranged hash function (Tavori and Dreizin). A
82 : * binary function whose argument types are _Key and size_t and
83 : * whose result type is size_t. Given arguments k and N, the
84 : * return value is in the range [0, N). Default: hash(k, N) =
85 : * h2(h1(k), N). If _Hash is anything other than the default, _H1
86 : * and _H2 are ignored.
87 : *
88 : * @tparam _RehashPolicy Policy class with three members, all of
89 : * which govern the bucket count. _M_next_bkt(n) returns a bucket
90 : * count no smaller than n. _M_bkt_for_elements(n) returns a
91 : * bucket count appropriate for an element count of n.
92 : * _M_need_rehash(n_bkt, n_elt, n_ins) determines whether, if the
93 : * current bucket count is n_bkt and the current element count is
94 : * n_elt, we need to increase the bucket count. If so, returns
95 : * make_pair(true, n), where n is the new bucket count. If not,
96 : * returns make_pair(false, <anything>)
97 : *
98 : * @tparam _Traits Compile-time class with three boolean
99 : * std::integral_constant members: __cache_hash_code, __constant_iterators,
100 : * __unique_keys.
101 : *
102 : * Each _Hashtable data structure has:
103 : *
104 : * - _Bucket[] _M_buckets
105 : * - _Hash_node_base _M_before_begin
106 : * - size_type _M_bucket_count
107 : * - size_type _M_element_count
108 : *
109 : * with _Bucket being _Hash_node* and _Hash_node containing:
110 : *
111 : * - _Hash_node* _M_next
112 : * - Tp _M_value
113 : * - size_t _M_hash_code if cache_hash_code is true
114 : *
115 : * In terms of Standard containers the hashtable is like the aggregation of:
116 : *
117 : * - std::forward_list<_Node> containing the elements
118 : * - std::vector<std::forward_list<_Node>::iterator> representing the buckets
119 : *
120 : * The non-empty buckets contain the node before the first node in the
121 : * bucket. This design makes it possible to implement something like a
122 : * std::forward_list::insert_after on container insertion and
123 : * std::forward_list::erase_after on container erase
124 : * calls. _M_before_begin is equivalent to
125 : * std::forward_list::before_begin. Empty buckets contain
126 : * nullptr. Note that one of the non-empty buckets contains
127 : * &_M_before_begin which is not a dereferenceable node so the
128 : * node pointer in a bucket shall never be dereferenced, only its
129 : * next node can be.
130 : *
131 : * Walking through a bucket's nodes requires a check on the hash code to
132 : * see if each node is still in the bucket. Such a design assumes a
133 : * quite efficient hash functor and is one of the reasons it is
134 : * highly advisable to set __cache_hash_code to true.
135 : *
136 : * The container iterators are simply built from nodes. This way
137 : * incrementing the iterator is perfectly efficient independent of
138 : * how many empty buckets there are in the container.
139 : *
140 : * On insert we compute the element's hash code and use it to find the
141 : * bucket index. If the element must be inserted in an empty bucket
142 : * we add it at the beginning of the singly linked list and make the
143 : * bucket point to _M_before_begin. The bucket that used to point to
144 : * _M_before_begin, if any, is updated to point to its new before
145 : * begin node.
146 : *
147 : * On erase, the simple iterator design requires using the hash
148 : * functor to get the index of the bucket to update. For this
149 : * reason, when __cache_hash_code is set to false the hash functor must
150 : * not throw and this is enforced by a static assertion.
151 : *
152 : * Functionality is implemented by decomposition into base classes,
153 : * where the derived _Hashtable class is used in _Map_base,
154 : * _Insert, _Rehash_base, and _Equality base classes to access the
155 : * "this" pointer. _Hashtable_base is used in the base classes as a
156 : * non-recursive, fully-completed-type so that detailed nested type
157 : * information, such as iterator type and node type, can be
158 : * used. This is similar to the "Curiously Recurring Template
159 : * Pattern" (CRTP) technique, but uses a reconstructed, not
160 : * explicitly passed, template pattern.
161 : *
162 : * Base class templates are:
163 : * - __detail::_Hashtable_base
164 : * - __detail::_Map_base
165 : * - __detail::_Insert
166 : * - __detail::_Rehash_base
167 : * - __detail::_Equality
168 : */
169 : template<typename _Key, typename _Value, typename _Alloc,
170 : typename _ExtractKey, typename _Equal,
171 : typename _H1, typename _H2, typename _Hash,
172 : typename _RehashPolicy, typename _Traits>
173 : class _Hashtable
174 : : public __detail::_Hashtable_base<_Key, _Value, _ExtractKey, _Equal,
175 : _H1, _H2, _Hash, _Traits>,
176 : public __detail::_Map_base<_Key, _Value, _Alloc, _ExtractKey, _Equal,
177 : _H1, _H2, _Hash, _RehashPolicy, _Traits>,
178 : public __detail::_Insert<_Key, _Value, _Alloc, _ExtractKey, _Equal,
179 : _H1, _H2, _Hash, _RehashPolicy, _Traits>,
180 : public __detail::_Rehash_base<_Key, _Value, _Alloc, _ExtractKey, _Equal,
181 : _H1, _H2, _Hash, _RehashPolicy, _Traits>,
182 : public __detail::_Equality<_Key, _Value, _Alloc, _ExtractKey, _Equal,
183 : _H1, _H2, _Hash, _RehashPolicy, _Traits>,
184 : private __detail::_Hashtable_alloc<
185 : __alloc_rebind<_Alloc,
186 : __detail::_Hash_node<_Value,
187 : _Traits::__hash_cached::value>>>
188 : {
189 : using __traits_type = _Traits;
190 : using __hash_cached = typename __traits_type::__hash_cached;
191 : using __node_type = __detail::_Hash_node<_Value, __hash_cached::value>;
192 : using __node_alloc_type = __alloc_rebind<_Alloc, __node_type>;
193 :
194 : using __hashtable_alloc = __detail::_Hashtable_alloc<__node_alloc_type>;
195 :
196 : using __value_alloc_traits =
197 : typename __hashtable_alloc::__value_alloc_traits;
198 : using __node_alloc_traits =
199 : typename __hashtable_alloc::__node_alloc_traits;
200 : using __node_base = typename __hashtable_alloc::__node_base;
201 : using __bucket_type = typename __hashtable_alloc::__bucket_type;
202 :
203 : public:
204 : typedef _Key key_type;
205 : typedef _Value value_type;
206 : typedef _Alloc allocator_type;
207 : typedef _Equal key_equal;
208 :
209 : // mapped_type, if present, comes from _Map_base.
210 : // hasher, if present, comes from _Hash_code_base/_Hashtable_base.
211 : typedef typename __value_alloc_traits::pointer pointer;
212 : typedef typename __value_alloc_traits::const_pointer const_pointer;
213 : typedef value_type& reference;
214 : typedef const value_type& const_reference;
215 :
216 : private:
217 : using __rehash_type = _RehashPolicy;
218 : using __rehash_state = typename __rehash_type::_State;
219 :
220 : using __constant_iterators = typename __traits_type::__constant_iterators;
221 : using __unique_keys = typename __traits_type::__unique_keys;
222 :
223 : using __key_extract = typename std::conditional<
224 : __constant_iterators::value,
225 : __detail::_Identity,
226 : __detail::_Select1st>::type;
227 :
228 : using __hashtable_base = __detail::
229 : _Hashtable_base<_Key, _Value, _ExtractKey,
230 : _Equal, _H1, _H2, _Hash, _Traits>;
231 :
232 : using __hash_code_base = typename __hashtable_base::__hash_code_base;
233 : using __hash_code = typename __hashtable_base::__hash_code;
234 : using __ireturn_type = typename __hashtable_base::__ireturn_type;
235 :
236 : using __map_base = __detail::_Map_base<_Key, _Value, _Alloc, _ExtractKey,
237 : _Equal, _H1, _H2, _Hash,
238 : _RehashPolicy, _Traits>;
239 :
240 : using __rehash_base = __detail::_Rehash_base<_Key, _Value, _Alloc,
241 : _ExtractKey, _Equal,
242 : _H1, _H2, _Hash,
243 : _RehashPolicy, _Traits>;
244 :
245 : using __eq_base = __detail::_Equality<_Key, _Value, _Alloc, _ExtractKey,
246 : _Equal, _H1, _H2, _Hash,
247 : _RehashPolicy, _Traits>;
248 :
249 : using __reuse_or_alloc_node_type =
250 : __detail::_ReuseOrAllocNode<__node_alloc_type>;
251 :
252 : // Metaprogramming for picking apart hash caching.
253 : template<typename _Cond>
254 : using __if_hash_cached = __or_<__not_<__hash_cached>, _Cond>;
255 :
256 : template<typename _Cond>
257 : using __if_hash_not_cached = __or_<__hash_cached, _Cond>;
258 :
259 : // Compile-time diagnostics.
260 :
261 : // _Hash_code_base has everything protected, so use this derived type to
262 : // access it.
263 : struct __hash_code_base_access : __hash_code_base
264 : { using __hash_code_base::_M_bucket_index; };
265 :
266 : // Getting a bucket index from a node shall not throw because it is used
267 : // in methods (erase, swap...) that shall not throw.
268 : static_assert(noexcept(declval<const __hash_code_base_access&>()
269 : ._M_bucket_index((const __node_type*)nullptr,
270 : (std::size_t)0)),
271 : "Cache the hash code or qualify your functors involved"
272 : " in hash code and bucket index computation with noexcept");
273 :
274 : // Following two static assertions are necessary to guarantee
275 : // that local_iterator will be default constructible.
276 :
277 : // When hash codes are cached local iterator inherits from H2 functor
278 : // which must then be default constructible.
279 : static_assert(__if_hash_cached<is_default_constructible<_H2>>::value,
280 : "Functor used to map hash code to bucket index"
281 : " must be default constructible");
282 :
283 : template<typename _Keya, typename _Valuea, typename _Alloca,
284 : typename _ExtractKeya, typename _Equala,
285 : typename _H1a, typename _H2a, typename _Hasha,
286 : typename _RehashPolicya, typename _Traitsa,
287 : bool _Unique_keysa>
288 : friend struct __detail::_Map_base;
289 :
290 : template<typename _Keya, typename _Valuea, typename _Alloca,
291 : typename _ExtractKeya, typename _Equala,
292 : typename _H1a, typename _H2a, typename _Hasha,
293 : typename _RehashPolicya, typename _Traitsa>
294 : friend struct __detail::_Insert_base;
295 :
296 : template<typename _Keya, typename _Valuea, typename _Alloca,
297 : typename _ExtractKeya, typename _Equala,
298 : typename _H1a, typename _H2a, typename _Hasha,
299 : typename _RehashPolicya, typename _Traitsa,
300 : bool _Constant_iteratorsa>
301 : friend struct __detail::_Insert;
302 :
303 : public:
304 : using size_type = typename __hashtable_base::size_type;
305 : using difference_type = typename __hashtable_base::difference_type;
306 :
307 : using iterator = typename __hashtable_base::iterator;
308 : using const_iterator = typename __hashtable_base::const_iterator;
309 :
310 : using local_iterator = typename __hashtable_base::local_iterator;
311 : using const_local_iterator = typename __hashtable_base::
312 : const_local_iterator;
313 :
314 : #if __cplusplus > 201402L
315 : using node_type = _Node_handle<_Key, _Value, __node_alloc_type>;
316 : using insert_return_type = _Node_insert_return<iterator, node_type>;
317 : #endif
318 :
319 : private:
320 : __bucket_type* _M_buckets = &_M_single_bucket;
321 : size_type _M_bucket_count = 1;
322 : __node_base _M_before_begin;
323 : size_type _M_element_count = 0;
324 : _RehashPolicy _M_rehash_policy;
325 :
326 : // A single bucket used when only need for 1 bucket. Especially
327 : // interesting in move semantic to leave hashtable with only 1 buckets
328 : // which is not allocated so that we can have those operations noexcept
329 : // qualified.
330 : // Note that we can't leave hashtable with 0 bucket without adding
331 : // numerous checks in the code to avoid 0 modulus.
332 : __bucket_type _M_single_bucket = nullptr;
333 :
334 : bool
335 106 : _M_uses_single_bucket(__bucket_type* __bkts) const
336 106 : { return __builtin_expect(__bkts == &_M_single_bucket, false); }
337 :
338 : bool
339 : _M_uses_single_bucket() const
340 : { return _M_uses_single_bucket(_M_buckets); }
341 :
342 : __hashtable_alloc&
343 : _M_base_alloc() { return *this; }
344 :
345 : __bucket_type*
346 86 : _M_allocate_buckets(size_type __n)
347 : {
348 86 : if (__builtin_expect(__n == 1, false))
349 : {
350 0 : _M_single_bucket = nullptr;
351 0 : return &_M_single_bucket;
352 : }
353 :
354 86 : return __hashtable_alloc::_M_allocate_buckets(__n);
355 : }
356 :
357 : void
358 106 : _M_deallocate_buckets(__bucket_type* __bkts, size_type __n)
359 : {
360 106 : if (_M_uses_single_bucket(__bkts))
361 20 : return;
362 :
363 86 : __hashtable_alloc::_M_deallocate_buckets(__bkts, __n);
364 : }
365 :
366 : void
367 106 : _M_deallocate_buckets()
368 106 : { _M_deallocate_buckets(_M_buckets, _M_bucket_count); }
369 :
370 : // Gets bucket begin, deals with the fact that non-empty buckets contain
371 : // their before begin node.
372 : __node_type*
373 : _M_bucket_begin(size_type __bkt) const;
374 :
375 : __node_type*
376 106 : _M_begin() const
377 106 : { return static_cast<__node_type*>(_M_before_begin._M_nxt); }
378 :
379 : template<typename _NodeGenerator>
380 : void
381 : _M_assign(const _Hashtable&, const _NodeGenerator&);
382 :
383 : void
384 : _M_move_assign(_Hashtable&&, std::true_type);
385 :
386 : void
387 : _M_move_assign(_Hashtable&&, std::false_type);
388 :
389 : void
390 : _M_reset() noexcept;
391 :
392 1 : _Hashtable(const _H1& __h1, const _H2& __h2, const _Hash& __h,
393 : const _Equal& __eq, const _ExtractKey& __exk,
394 : const allocator_type& __a)
395 : : __hashtable_base(__exk, __h1, __h2, __h, __eq),
396 1 : __hashtable_alloc(__node_alloc_type(__a))
397 1 : { }
398 :
399 : public:
400 : // Constructor, destructor, assignment, swap
401 20 : _Hashtable() = default;
402 : _Hashtable(size_type __bucket_hint,
403 : const _H1&, const _H2&, const _Hash&,
404 : const _Equal&, const _ExtractKey&,
405 : const allocator_type&);
406 :
407 : template<typename _InputIterator>
408 : _Hashtable(_InputIterator __first, _InputIterator __last,
409 : size_type __bucket_hint,
410 : const _H1&, const _H2&, const _Hash&,
411 : const _Equal&, const _ExtractKey&,
412 : const allocator_type&);
413 :
414 : _Hashtable(const _Hashtable&);
415 :
416 : _Hashtable(_Hashtable&&) noexcept;
417 :
418 : _Hashtable(const _Hashtable&, const allocator_type&);
419 :
420 : _Hashtable(_Hashtable&&, const allocator_type&);
421 :
422 : // Use delegating constructors.
423 : explicit
424 : _Hashtable(const allocator_type& __a)
425 : : __hashtable_alloc(__node_alloc_type(__a))
426 : { }
427 :
428 : explicit
429 : _Hashtable(size_type __n,
430 : const _H1& __hf = _H1(),
431 : const key_equal& __eql = key_equal(),
432 : const allocator_type& __a = allocator_type())
433 : : _Hashtable(__n, __hf, _H2(), _Hash(), __eql,
434 : __key_extract(), __a)
435 : { }
436 :
437 : template<typename _InputIterator>
438 : _Hashtable(_InputIterator __f, _InputIterator __l,
439 : size_type __n = 0,
440 : const _H1& __hf = _H1(),
441 : const key_equal& __eql = key_equal(),
442 : const allocator_type& __a = allocator_type())
443 : : _Hashtable(__f, __l, __n, __hf, _H2(), _Hash(), __eql,
444 : __key_extract(), __a)
445 : { }
446 :
447 1 : _Hashtable(initializer_list<value_type> __l,
448 : size_type __n = 0,
449 : const _H1& __hf = _H1(),
450 : const key_equal& __eql = key_equal(),
451 : const allocator_type& __a = allocator_type())
452 : : _Hashtable(__l.begin(), __l.end(), __n, __hf, _H2(), _Hash(), __eql,
453 1 : __key_extract(), __a)
454 1 : { }
455 :
456 : _Hashtable&
457 : operator=(const _Hashtable& __ht);
458 :
459 : _Hashtable&
460 : operator=(_Hashtable&& __ht)
461 : noexcept(__node_alloc_traits::_S_nothrow_move()
462 : && is_nothrow_move_assignable<_H1>::value
463 : && is_nothrow_move_assignable<_Equal>::value)
464 : {
465 : constexpr bool __move_storage =
466 : __node_alloc_traits::_S_propagate_on_move_assign()
467 : || __node_alloc_traits::_S_always_equal();
468 : _M_move_assign(std::move(__ht), __bool_constant<__move_storage>());
469 : return *this;
470 : }
471 :
472 : _Hashtable&
473 : operator=(initializer_list<value_type> __l)
474 : {
475 : __reuse_or_alloc_node_type __roan(_M_begin(), *this);
476 : _M_before_begin._M_nxt = nullptr;
477 : clear();
478 : this->_M_insert_range(__l.begin(), __l.end(), __roan);
479 : return *this;
480 : }
481 :
482 : ~_Hashtable() noexcept;
483 :
484 : void
485 : swap(_Hashtable&)
486 : noexcept(__and_<__is_nothrow_swappable<_H1>,
487 : __is_nothrow_swappable<_Equal>>::value);
488 :
489 : // Basic container operations
490 : iterator
491 : begin() noexcept
492 : { return iterator(_M_begin()); }
493 :
494 : const_iterator
495 : begin() const noexcept
496 : { return const_iterator(_M_begin()); }
497 :
498 : iterator
499 10 : end() noexcept
500 10 : { return iterator(nullptr); }
501 :
502 : const_iterator
503 : end() const noexcept
504 : { return const_iterator(nullptr); }
505 :
506 : const_iterator
507 : cbegin() const noexcept
508 : { return const_iterator(_M_begin()); }
509 :
510 : const_iterator
511 : cend() const noexcept
512 : { return const_iterator(nullptr); }
513 :
514 : size_type
515 : size() const noexcept
516 : { return _M_element_count; }
517 :
518 : bool
519 : empty() const noexcept
520 : { return size() == 0; }
521 :
522 : allocator_type
523 : get_allocator() const noexcept
524 : { return allocator_type(this->_M_node_allocator()); }
525 :
526 : size_type
527 : max_size() const noexcept
528 : { return __node_alloc_traits::max_size(this->_M_node_allocator()); }
529 :
530 : // Observers
531 : key_equal
532 : key_eq() const
533 : { return this->_M_eq(); }
534 :
535 : // hash_function, if present, comes from _Hash_code_base.
536 :
537 : // Bucket operations
538 : size_type
539 : bucket_count() const noexcept
540 : { return _M_bucket_count; }
541 :
542 : size_type
543 : max_bucket_count() const noexcept
544 : { return max_size(); }
545 :
546 : size_type
547 : bucket_size(size_type __n) const
548 : { return std::distance(begin(__n), end(__n)); }
549 :
550 : size_type
551 : bucket(const key_type& __k) const
552 : { return _M_bucket_index(__k, this->_M_hash_code(__k)); }
553 :
554 : local_iterator
555 : begin(size_type __n)
556 : {
557 : return local_iterator(*this, _M_bucket_begin(__n),
558 : __n, _M_bucket_count);
559 : }
560 :
561 : local_iterator
562 : end(size_type __n)
563 : { return local_iterator(*this, nullptr, __n, _M_bucket_count); }
564 :
565 : const_local_iterator
566 : begin(size_type __n) const
567 : {
568 : return const_local_iterator(*this, _M_bucket_begin(__n),
569 : __n, _M_bucket_count);
570 : }
571 :
572 : const_local_iterator
573 : end(size_type __n) const
574 : { return const_local_iterator(*this, nullptr, __n, _M_bucket_count); }
575 :
576 : // DR 691.
577 : const_local_iterator
578 : cbegin(size_type __n) const
579 : {
580 : return const_local_iterator(*this, _M_bucket_begin(__n),
581 : __n, _M_bucket_count);
582 : }
583 :
584 : const_local_iterator
585 : cend(size_type __n) const
586 : { return const_local_iterator(*this, nullptr, __n, _M_bucket_count); }
587 :
588 : float
589 : load_factor() const noexcept
590 : {
591 : return static_cast<float>(size()) / static_cast<float>(bucket_count());
592 : }
593 :
594 : // max_load_factor, if present, comes from _Rehash_base.
595 :
596 : // Generalization of max_load_factor. Extension, not found in
597 : // TR1. Only useful if _RehashPolicy is something other than
598 : // the default.
599 : const _RehashPolicy&
600 : __rehash_policy() const
601 : { return _M_rehash_policy; }
602 :
603 : void
604 : __rehash_policy(const _RehashPolicy& __pol)
605 : { _M_rehash_policy = __pol; }
606 :
607 : // Lookup.
608 : iterator
609 : find(const key_type& __k);
610 :
611 : const_iterator
612 : find(const key_type& __k) const;
613 :
614 : size_type
615 : count(const key_type& __k) const;
616 :
617 : std::pair<iterator, iterator>
618 : equal_range(const key_type& __k);
619 :
620 : std::pair<const_iterator, const_iterator>
621 : equal_range(const key_type& __k) const;
622 :
623 : protected:
624 : // Bucket index computation helpers.
625 : size_type
626 1255 : _M_bucket_index(__node_type* __n) const noexcept
627 1255 : { return __hash_code_base::_M_bucket_index(__n, _M_bucket_count); }
628 :
629 : size_type
630 1698 : _M_bucket_index(const key_type& __k, __hash_code __c) const
631 1698 : { return __hash_code_base::_M_bucket_index(__k, __c, _M_bucket_count); }
632 :
633 : // Find and insert helper functions and types
634 : // Find the node before the one matching the criteria.
635 : __node_base*
636 : _M_find_before_node(size_type, const key_type&, __hash_code) const;
637 :
638 : __node_type*
639 1411 : _M_find_node(size_type __bkt, const key_type& __key,
640 : __hash_code __c) const
641 : {
642 1411 : __node_base* __before_n = _M_find_before_node(__bkt, __key, __c);
643 1411 : if (__before_n)
644 210 : return static_cast<__node_type*>(__before_n->_M_nxt);
645 1201 : return nullptr;
646 : }
647 :
648 : // Insert a node at the beginning of a bucket.
649 : void
650 : _M_insert_bucket_begin(size_type, __node_type*);
651 :
652 : // Remove the bucket first node
653 : void
654 : _M_remove_bucket_begin(size_type __bkt, __node_type* __next_n,
655 : size_type __next_bkt);
656 :
657 : // Get the node before __n in the bucket __bkt
658 : __node_base*
659 : _M_get_previous_node(size_type __bkt, __node_base* __n);
660 :
661 : // Insert node with hash code __code, in bucket bkt if no rehash (assumes
662 : // no element with its key already present). Take ownership of the node,
663 : // deallocate it on exception.
664 : iterator
665 : _M_insert_unique_node(size_type __bkt, __hash_code __code,
666 : __node_type* __n);
667 :
668 : // Insert node with hash code __code. Take ownership of the node,
669 : // deallocate it on exception.
670 : iterator
671 : _M_insert_multi_node(__node_type* __hint,
672 : __hash_code __code, __node_type* __n);
673 :
674 : template<typename... _Args>
675 : std::pair<iterator, bool>
676 : _M_emplace(std::true_type, _Args&&... __args);
677 :
678 : template<typename... _Args>
679 : iterator
680 : _M_emplace(std::false_type __uk, _Args&&... __args)
681 : { return _M_emplace(cend(), __uk, std::forward<_Args>(__args)...); }
682 :
683 : // Emplace with hint, useless when keys are unique.
684 : template<typename... _Args>
685 : iterator
686 : _M_emplace(const_iterator, std::true_type __uk, _Args&&... __args)
687 : { return _M_emplace(__uk, std::forward<_Args>(__args)...).first; }
688 :
689 : template<typename... _Args>
690 : iterator
691 : _M_emplace(const_iterator, std::false_type, _Args&&... __args);
692 :
693 : template<typename _Arg, typename _NodeGenerator>
694 : std::pair<iterator, bool>
695 : _M_insert(_Arg&&, const _NodeGenerator&, std::true_type);
696 :
697 : template<typename _Arg, typename _NodeGenerator>
698 : iterator
699 : _M_insert(_Arg&& __arg, const _NodeGenerator& __node_gen,
700 : std::false_type __uk)
701 : {
702 : return _M_insert(cend(), std::forward<_Arg>(__arg), __node_gen,
703 : __uk);
704 : }
705 :
706 : // Insert with hint, not used when keys are unique.
707 : template<typename _Arg, typename _NodeGenerator>
708 : iterator
709 : _M_insert(const_iterator, _Arg&& __arg,
710 : const _NodeGenerator& __node_gen, std::true_type __uk)
711 : {
712 : return
713 : _M_insert(std::forward<_Arg>(__arg), __node_gen, __uk).first;
714 : }
715 :
716 : // Insert with hint when keys are not unique.
717 : template<typename _Arg, typename _NodeGenerator>
718 : iterator
719 : _M_insert(const_iterator, _Arg&&,
720 : const _NodeGenerator&, std::false_type);
721 :
722 : size_type
723 : _M_erase(std::true_type, const key_type&);
724 :
725 : size_type
726 : _M_erase(std::false_type, const key_type&);
727 :
728 : iterator
729 : _M_erase(size_type __bkt, __node_base* __prev_n, __node_type* __n);
730 :
731 : public:
732 : // Emplace
733 : template<typename... _Args>
734 : __ireturn_type
735 : emplace(_Args&&... __args)
736 : { return _M_emplace(__unique_keys(), std::forward<_Args>(__args)...); }
737 :
738 : template<typename... _Args>
739 : iterator
740 : emplace_hint(const_iterator __hint, _Args&&... __args)
741 : {
742 : return _M_emplace(__hint, __unique_keys(),
743 : std::forward<_Args>(__args)...);
744 : }
745 :
746 : // Insert member functions via inheritance.
747 :
748 : // Erase
749 : iterator
750 : erase(const_iterator);
751 :
752 : // LWG 2059.
753 : iterator
754 0 : erase(iterator __it)
755 0 : { return erase(const_iterator(__it)); }
756 :
757 : size_type
758 : erase(const key_type& __k)
759 : { return _M_erase(__unique_keys(), __k); }
760 :
761 : iterator
762 : erase(const_iterator, const_iterator);
763 :
764 : void
765 : clear() noexcept;
766 :
767 : // Set number of buckets to be appropriate for container of n element.
768 : void rehash(size_type __n);
769 :
770 : // DR 1189.
771 : // reserve, if present, comes from _Rehash_base.
772 :
773 : #if __cplusplus > 201402L
774 : /// Re-insert an extracted node into a container with unique keys.
775 : insert_return_type
776 : _M_reinsert_node(node_type&& __nh)
777 : {
778 : insert_return_type __ret;
779 : if (__nh.empty())
780 : __ret.position = end();
781 : else
782 : {
783 : __glibcxx_assert(get_allocator() == __nh.get_allocator());
784 :
785 : const key_type& __k = __nh._M_key();
786 : __hash_code __code = this->_M_hash_code(__k);
787 : size_type __bkt = _M_bucket_index(__k, __code);
788 : if (__node_type* __n = _M_find_node(__bkt, __k, __code))
789 : {
790 : __ret.node = std::move(__nh);
791 : __ret.position = iterator(__n);
792 : __ret.inserted = false;
793 : }
794 : else
795 : {
796 : __ret.position
797 : = _M_insert_unique_node(__bkt, __code, __nh._M_ptr);
798 : __nh._M_ptr = nullptr;
799 : __ret.inserted = true;
800 : }
801 : }
802 : return __ret;
803 : }
804 :
805 : /// Re-insert an extracted node into a container with equivalent keys.
806 : iterator
807 : _M_reinsert_node_multi(const_iterator __hint, node_type&& __nh)
808 : {
809 : iterator __ret;
810 : if (__nh.empty())
811 : __ret = end();
812 : else
813 : {
814 : __glibcxx_assert(get_allocator() == __nh.get_allocator());
815 :
816 : auto __code = this->_M_hash_code(__nh._M_key());
817 : auto __node = std::exchange(__nh._M_ptr, nullptr);
818 : // FIXME: this deallocates the node on exception.
819 : __ret = _M_insert_multi_node(__hint._M_cur, __code, __node);
820 : }
821 : return __ret;
822 : }
823 :
824 : /// Extract a node.
825 : node_type
826 : extract(const_iterator __pos)
827 : {
828 : __node_type* __n = __pos._M_cur;
829 : size_t __bkt = _M_bucket_index(__n);
830 :
831 : // Look for previous node to unlink it from the erased one, this
832 : // is why we need buckets to contain the before begin to make
833 : // this search fast.
834 : __node_base* __prev_n = _M_get_previous_node(__bkt, __n);
835 :
836 : if (__prev_n == _M_buckets[__bkt])
837 : _M_remove_bucket_begin(__bkt, __n->_M_next(),
838 : __n->_M_nxt ? _M_bucket_index(__n->_M_next()) : 0);
839 : else if (__n->_M_nxt)
840 : {
841 : size_type __next_bkt = _M_bucket_index(__n->_M_next());
842 : if (__next_bkt != __bkt)
843 : _M_buckets[__next_bkt] = __prev_n;
844 : }
845 :
846 : __prev_n->_M_nxt = __n->_M_nxt;
847 : __n->_M_nxt = nullptr;
848 : --_M_element_count;
849 : return { __n, this->_M_node_allocator() };
850 : }
851 :
852 : /// Extract a node.
853 : node_type
854 : extract(const _Key& __k)
855 : {
856 : node_type __nh;
857 : auto __pos = find(__k);
858 : if (__pos != end())
859 : __nh = extract(const_iterator(__pos));
860 : return __nh;
861 : }
862 :
863 : /// Merge from a compatible container into one with unique keys.
864 : template<typename _Compatible_Hashtable>
865 : void
866 : _M_merge_unique(_Compatible_Hashtable& __src) noexcept
867 : {
868 : static_assert(is_same_v<typename _Compatible_Hashtable::node_type,
869 : node_type>, "Node types are compatible");
870 : __glibcxx_assert(get_allocator() == __src.get_allocator());
871 :
872 : for (auto __i = __src.begin(), __end = __src.end(); __i != __end;)
873 : {
874 : auto __pos = __i++;
875 : const key_type& __k = this->_M_extract()(__pos._M_cur->_M_v());
876 : __hash_code __code = this->_M_hash_code(__k);
877 : size_type __bkt = _M_bucket_index(__k, __code);
878 : if (_M_find_node(__bkt, __k, __code) == nullptr)
879 : {
880 : auto __nh = __src.extract(__pos);
881 : _M_insert_unique_node(__bkt, __code, __nh._M_ptr);
882 : __nh._M_ptr = nullptr;
883 : }
884 : }
885 : }
886 :
887 : /// Merge from a compatible container into one with equivalent keys.
888 : template<typename _Compatible_Hashtable>
889 : void
890 : _M_merge_multi(_Compatible_Hashtable& __src) noexcept
891 : {
892 : static_assert(is_same_v<typename _Compatible_Hashtable::node_type,
893 : node_type>, "Node types are compatible");
894 : __glibcxx_assert(get_allocator() == __src.get_allocator());
895 :
896 : this->reserve(size() + __src.size());
897 : for (auto __i = __src.begin(), __end = __src.end(); __i != __end;)
898 : _M_reinsert_node_multi(cend(), __src.extract(__i++));
899 : }
900 : #endif // C++17
901 :
902 : private:
903 : // Helper rehash method used when keys are unique.
904 : void _M_rehash_aux(size_type __n, std::true_type);
905 :
906 : // Helper rehash method used when keys can be non-unique.
907 : void _M_rehash_aux(size_type __n, std::false_type);
908 :
909 : // Unconditionally change size of bucket array to n, restore
910 : // hash policy state to __state on exception.
911 : void _M_rehash(size_type __n, const __rehash_state& __state);
912 : };
913 :
914 :
915 : // Definitions of class template _Hashtable's out-of-line member functions.
916 : template<typename _Key, typename _Value,
917 : typename _Alloc, typename _ExtractKey, typename _Equal,
918 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
919 : typename _Traits>
920 : auto
921 202 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
922 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
923 : _M_bucket_begin(size_type __bkt) const
924 : -> __node_type*
925 : {
926 202 : __node_base* __n = _M_buckets[__bkt];
927 202 : return __n ? static_cast<__node_type*>(__n->_M_nxt) : nullptr;
928 : }
929 :
930 : template<typename _Key, typename _Value,
931 : typename _Alloc, typename _ExtractKey, typename _Equal,
932 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
933 : typename _Traits>
934 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
935 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
936 : _Hashtable(size_type __bucket_hint,
937 : const _H1& __h1, const _H2& __h2, const _Hash& __h,
938 : const _Equal& __eq, const _ExtractKey& __exk,
939 : const allocator_type& __a)
940 : : _Hashtable(__h1, __h2, __h, __eq, __exk, __a)
941 : {
942 : auto __bkt = _M_rehash_policy._M_next_bkt(__bucket_hint);
943 : if (__bkt > _M_bucket_count)
944 : {
945 : _M_buckets = _M_allocate_buckets(__bkt);
946 : _M_bucket_count = __bkt;
947 : }
948 : }
949 :
950 : template<typename _Key, typename _Value,
951 : typename _Alloc, typename _ExtractKey, typename _Equal,
952 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
953 : typename _Traits>
954 : template<typename _InputIterator>
955 1 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
956 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
957 : _Hashtable(_InputIterator __f, _InputIterator __l,
958 : size_type __bucket_hint,
959 : const _H1& __h1, const _H2& __h2, const _Hash& __h,
960 : const _Equal& __eq, const _ExtractKey& __exk,
961 : const allocator_type& __a)
962 1 : : _Hashtable(__h1, __h2, __h, __eq, __exk, __a)
963 : {
964 1 : auto __nb_elems = __detail::__distance_fw(__f, __l);
965 2 : auto __bkt_count =
966 : _M_rehash_policy._M_next_bkt(
967 2 : std::max(_M_rehash_policy._M_bkt_for_elements(__nb_elems),
968 : __bucket_hint));
969 :
970 1 : if (__bkt_count > _M_bucket_count)
971 : {
972 1 : _M_buckets = _M_allocate_buckets(__bkt_count);
973 1 : _M_bucket_count = __bkt_count;
974 : }
975 :
976 15 : for (; __f != __l; ++__f)
977 7 : this->insert(*__f);
978 1 : }
979 :
980 : template<typename _Key, typename _Value,
981 : typename _Alloc, typename _ExtractKey, typename _Equal,
982 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
983 : typename _Traits>
984 : auto
985 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
986 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
987 : operator=(const _Hashtable& __ht)
988 : -> _Hashtable&
989 : {
990 : if (&__ht == this)
991 : return *this;
992 :
993 : if (__node_alloc_traits::_S_propagate_on_copy_assign())
994 : {
995 : auto& __this_alloc = this->_M_node_allocator();
996 : auto& __that_alloc = __ht._M_node_allocator();
997 : if (!__node_alloc_traits::_S_always_equal()
998 : && __this_alloc != __that_alloc)
999 : {
1000 : // Replacement allocator cannot free existing storage.
1001 : this->_M_deallocate_nodes(_M_begin());
1002 : _M_before_begin._M_nxt = nullptr;
1003 : _M_deallocate_buckets();
1004 : _M_buckets = nullptr;
1005 : std::__alloc_on_copy(__this_alloc, __that_alloc);
1006 : __hashtable_base::operator=(__ht);
1007 : _M_bucket_count = __ht._M_bucket_count;
1008 : _M_element_count = __ht._M_element_count;
1009 : _M_rehash_policy = __ht._M_rehash_policy;
1010 : __try
1011 : {
1012 : _M_assign(__ht,
1013 : [this](const __node_type* __n)
1014 : { return this->_M_allocate_node(__n->_M_v()); });
1015 : }
1016 : __catch(...)
1017 : {
1018 : // _M_assign took care of deallocating all memory. Now we
1019 : // must make sure this instance remains in a usable state.
1020 : _M_reset();
1021 : __throw_exception_again;
1022 : }
1023 : return *this;
1024 : }
1025 : std::__alloc_on_copy(__this_alloc, __that_alloc);
1026 : }
1027 :
1028 : // Reuse allocated buckets and nodes.
1029 : __bucket_type* __former_buckets = nullptr;
1030 : std::size_t __former_bucket_count = _M_bucket_count;
1031 : const __rehash_state& __former_state = _M_rehash_policy._M_state();
1032 :
1033 : if (_M_bucket_count != __ht._M_bucket_count)
1034 : {
1035 : __former_buckets = _M_buckets;
1036 : _M_buckets = _M_allocate_buckets(__ht._M_bucket_count);
1037 : _M_bucket_count = __ht._M_bucket_count;
1038 : }
1039 : else
1040 : __builtin_memset(_M_buckets, 0,
1041 : _M_bucket_count * sizeof(__bucket_type));
1042 :
1043 : __try
1044 : {
1045 : __hashtable_base::operator=(__ht);
1046 : _M_element_count = __ht._M_element_count;
1047 : _M_rehash_policy = __ht._M_rehash_policy;
1048 : __reuse_or_alloc_node_type __roan(_M_begin(), *this);
1049 : _M_before_begin._M_nxt = nullptr;
1050 : _M_assign(__ht,
1051 : [&__roan](const __node_type* __n)
1052 : { return __roan(__n->_M_v()); });
1053 : if (__former_buckets)
1054 : _M_deallocate_buckets(__former_buckets, __former_bucket_count);
1055 : }
1056 : __catch(...)
1057 : {
1058 : if (__former_buckets)
1059 : {
1060 : // Restore previous buckets.
1061 : _M_deallocate_buckets();
1062 : _M_rehash_policy._M_reset(__former_state);
1063 : _M_buckets = __former_buckets;
1064 : _M_bucket_count = __former_bucket_count;
1065 : }
1066 : __builtin_memset(_M_buckets, 0,
1067 : _M_bucket_count * sizeof(__bucket_type));
1068 : __throw_exception_again;
1069 : }
1070 : return *this;
1071 : }
1072 :
1073 : template<typename _Key, typename _Value,
1074 : typename _Alloc, typename _ExtractKey, typename _Equal,
1075 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1076 : typename _Traits>
1077 : template<typename _NodeGenerator>
1078 : void
1079 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1080 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1081 : _M_assign(const _Hashtable& __ht, const _NodeGenerator& __node_gen)
1082 : {
1083 : __bucket_type* __buckets = nullptr;
1084 : if (!_M_buckets)
1085 : _M_buckets = __buckets = _M_allocate_buckets(_M_bucket_count);
1086 :
1087 : __try
1088 : {
1089 : if (!__ht._M_before_begin._M_nxt)
1090 : return;
1091 :
1092 : // First deal with the special first node pointed to by
1093 : // _M_before_begin.
1094 : __node_type* __ht_n = __ht._M_begin();
1095 : __node_type* __this_n = __node_gen(__ht_n);
1096 : this->_M_copy_code(__this_n, __ht_n);
1097 : _M_before_begin._M_nxt = __this_n;
1098 : _M_buckets[_M_bucket_index(__this_n)] = &_M_before_begin;
1099 :
1100 : // Then deal with other nodes.
1101 : __node_base* __prev_n = __this_n;
1102 : for (__ht_n = __ht_n->_M_next(); __ht_n; __ht_n = __ht_n->_M_next())
1103 : {
1104 : __this_n = __node_gen(__ht_n);
1105 : __prev_n->_M_nxt = __this_n;
1106 : this->_M_copy_code(__this_n, __ht_n);
1107 : size_type __bkt = _M_bucket_index(__this_n);
1108 : if (!_M_buckets[__bkt])
1109 : _M_buckets[__bkt] = __prev_n;
1110 : __prev_n = __this_n;
1111 : }
1112 : }
1113 : __catch(...)
1114 : {
1115 : clear();
1116 : if (__buckets)
1117 : _M_deallocate_buckets();
1118 : __throw_exception_again;
1119 : }
1120 : }
1121 :
1122 : template<typename _Key, typename _Value,
1123 : typename _Alloc, typename _ExtractKey, typename _Equal,
1124 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1125 : typename _Traits>
1126 : void
1127 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1128 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1129 : _M_reset() noexcept
1130 : {
1131 : _M_rehash_policy._M_reset();
1132 : _M_bucket_count = 1;
1133 : _M_single_bucket = nullptr;
1134 : _M_buckets = &_M_single_bucket;
1135 : _M_before_begin._M_nxt = nullptr;
1136 : _M_element_count = 0;
1137 : }
1138 :
1139 : template<typename _Key, typename _Value,
1140 : typename _Alloc, typename _ExtractKey, typename _Equal,
1141 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1142 : typename _Traits>
1143 : void
1144 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1145 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1146 : _M_move_assign(_Hashtable&& __ht, std::true_type)
1147 : {
1148 : this->_M_deallocate_nodes(_M_begin());
1149 : _M_deallocate_buckets();
1150 : __hashtable_base::operator=(std::move(__ht));
1151 : _M_rehash_policy = __ht._M_rehash_policy;
1152 : if (!__ht._M_uses_single_bucket())
1153 : _M_buckets = __ht._M_buckets;
1154 : else
1155 : {
1156 : _M_buckets = &_M_single_bucket;
1157 : _M_single_bucket = __ht._M_single_bucket;
1158 : }
1159 : _M_bucket_count = __ht._M_bucket_count;
1160 : _M_before_begin._M_nxt = __ht._M_before_begin._M_nxt;
1161 : _M_element_count = __ht._M_element_count;
1162 : std::__alloc_on_move(this->_M_node_allocator(), __ht._M_node_allocator());
1163 :
1164 : // Fix buckets containing the _M_before_begin pointers that can't be
1165 : // moved.
1166 : if (_M_begin())
1167 : _M_buckets[_M_bucket_index(_M_begin())] = &_M_before_begin;
1168 : __ht._M_reset();
1169 : }
1170 :
1171 : template<typename _Key, typename _Value,
1172 : typename _Alloc, typename _ExtractKey, typename _Equal,
1173 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1174 : typename _Traits>
1175 : void
1176 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1177 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1178 : _M_move_assign(_Hashtable&& __ht, std::false_type)
1179 : {
1180 : if (__ht._M_node_allocator() == this->_M_node_allocator())
1181 : _M_move_assign(std::move(__ht), std::true_type());
1182 : else
1183 : {
1184 : // Can't move memory, move elements then.
1185 : __bucket_type* __former_buckets = nullptr;
1186 : size_type __former_bucket_count = _M_bucket_count;
1187 : const __rehash_state& __former_state = _M_rehash_policy._M_state();
1188 :
1189 : if (_M_bucket_count != __ht._M_bucket_count)
1190 : {
1191 : __former_buckets = _M_buckets;
1192 : _M_buckets = _M_allocate_buckets(__ht._M_bucket_count);
1193 : _M_bucket_count = __ht._M_bucket_count;
1194 : }
1195 : else
1196 : __builtin_memset(_M_buckets, 0,
1197 : _M_bucket_count * sizeof(__bucket_type));
1198 :
1199 : __try
1200 : {
1201 : __hashtable_base::operator=(std::move(__ht));
1202 : _M_element_count = __ht._M_element_count;
1203 : _M_rehash_policy = __ht._M_rehash_policy;
1204 : __reuse_or_alloc_node_type __roan(_M_begin(), *this);
1205 : _M_before_begin._M_nxt = nullptr;
1206 : _M_assign(__ht,
1207 : [&__roan](__node_type* __n)
1208 : { return __roan(std::move_if_noexcept(__n->_M_v())); });
1209 :
1210 : if (__former_buckets)
1211 : _M_deallocate_buckets(__former_buckets, __former_bucket_count);
1212 : __ht.clear();
1213 : }
1214 : __catch(...)
1215 : {
1216 : if (__former_buckets)
1217 : {
1218 : _M_deallocate_buckets();
1219 : _M_rehash_policy._M_reset(__former_state);
1220 : _M_buckets = __former_buckets;
1221 : _M_bucket_count = __former_bucket_count;
1222 : }
1223 : __builtin_memset(_M_buckets, 0,
1224 : _M_bucket_count * sizeof(__bucket_type));
1225 : __throw_exception_again;
1226 : }
1227 : }
1228 : }
1229 :
1230 : template<typename _Key, typename _Value,
1231 : typename _Alloc, typename _ExtractKey, typename _Equal,
1232 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1233 : typename _Traits>
1234 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1235 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1236 : _Hashtable(const _Hashtable& __ht)
1237 : : __hashtable_base(__ht),
1238 : __map_base(__ht),
1239 : __rehash_base(__ht),
1240 : __hashtable_alloc(
1241 : __node_alloc_traits::_S_select_on_copy(__ht._M_node_allocator())),
1242 : _M_buckets(nullptr),
1243 : _M_bucket_count(__ht._M_bucket_count),
1244 : _M_element_count(__ht._M_element_count),
1245 : _M_rehash_policy(__ht._M_rehash_policy)
1246 : {
1247 : _M_assign(__ht,
1248 : [this](const __node_type* __n)
1249 : { return this->_M_allocate_node(__n->_M_v()); });
1250 : }
1251 :
1252 : template<typename _Key, typename _Value,
1253 : typename _Alloc, typename _ExtractKey, typename _Equal,
1254 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1255 : typename _Traits>
1256 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1257 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1258 : _Hashtable(_Hashtable&& __ht) noexcept
1259 : : __hashtable_base(__ht),
1260 : __map_base(__ht),
1261 : __rehash_base(__ht),
1262 : __hashtable_alloc(std::move(__ht._M_base_alloc())),
1263 : _M_buckets(__ht._M_buckets),
1264 : _M_bucket_count(__ht._M_bucket_count),
1265 : _M_before_begin(__ht._M_before_begin._M_nxt),
1266 : _M_element_count(__ht._M_element_count),
1267 : _M_rehash_policy(__ht._M_rehash_policy)
1268 : {
1269 : // Update, if necessary, buckets if __ht is using its single bucket.
1270 : if (__ht._M_uses_single_bucket())
1271 : {
1272 : _M_buckets = &_M_single_bucket;
1273 : _M_single_bucket = __ht._M_single_bucket;
1274 : }
1275 :
1276 : // Update, if necessary, bucket pointing to before begin that hasn't
1277 : // moved.
1278 : if (_M_begin())
1279 : _M_buckets[_M_bucket_index(_M_begin())] = &_M_before_begin;
1280 :
1281 : __ht._M_reset();
1282 : }
1283 :
1284 : template<typename _Key, typename _Value,
1285 : typename _Alloc, typename _ExtractKey, typename _Equal,
1286 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1287 : typename _Traits>
1288 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1289 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1290 : _Hashtable(const _Hashtable& __ht, const allocator_type& __a)
1291 : : __hashtable_base(__ht),
1292 : __map_base(__ht),
1293 : __rehash_base(__ht),
1294 : __hashtable_alloc(__node_alloc_type(__a)),
1295 : _M_buckets(),
1296 : _M_bucket_count(__ht._M_bucket_count),
1297 : _M_element_count(__ht._M_element_count),
1298 : _M_rehash_policy(__ht._M_rehash_policy)
1299 : {
1300 : _M_assign(__ht,
1301 : [this](const __node_type* __n)
1302 : { return this->_M_allocate_node(__n->_M_v()); });
1303 : }
1304 :
1305 : template<typename _Key, typename _Value,
1306 : typename _Alloc, typename _ExtractKey, typename _Equal,
1307 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1308 : typename _Traits>
1309 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1310 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1311 : _Hashtable(_Hashtable&& __ht, const allocator_type& __a)
1312 : : __hashtable_base(__ht),
1313 : __map_base(__ht),
1314 : __rehash_base(__ht),
1315 : __hashtable_alloc(__node_alloc_type(__a)),
1316 : _M_buckets(nullptr),
1317 : _M_bucket_count(__ht._M_bucket_count),
1318 : _M_element_count(__ht._M_element_count),
1319 : _M_rehash_policy(__ht._M_rehash_policy)
1320 : {
1321 : if (__ht._M_node_allocator() == this->_M_node_allocator())
1322 : {
1323 : if (__ht._M_uses_single_bucket())
1324 : {
1325 : _M_buckets = &_M_single_bucket;
1326 : _M_single_bucket = __ht._M_single_bucket;
1327 : }
1328 : else
1329 : _M_buckets = __ht._M_buckets;
1330 :
1331 : _M_before_begin._M_nxt = __ht._M_before_begin._M_nxt;
1332 : // Update, if necessary, bucket pointing to before begin that hasn't
1333 : // moved.
1334 : if (_M_begin())
1335 : _M_buckets[_M_bucket_index(_M_begin())] = &_M_before_begin;
1336 : __ht._M_reset();
1337 : }
1338 : else
1339 : {
1340 : _M_assign(__ht,
1341 : [this](__node_type* __n)
1342 : {
1343 : return this->_M_allocate_node(
1344 : std::move_if_noexcept(__n->_M_v()));
1345 : });
1346 : __ht.clear();
1347 : }
1348 : }
1349 :
1350 : template<typename _Key, typename _Value,
1351 : typename _Alloc, typename _ExtractKey, typename _Equal,
1352 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1353 : typename _Traits>
1354 21 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1355 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1356 : ~_Hashtable() noexcept
1357 : {
1358 21 : clear();
1359 21 : _M_deallocate_buckets();
1360 21 : }
1361 :
1362 : template<typename _Key, typename _Value,
1363 : typename _Alloc, typename _ExtractKey, typename _Equal,
1364 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1365 : typename _Traits>
1366 : void
1367 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1368 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1369 : swap(_Hashtable& __x)
1370 : noexcept(__and_<__is_nothrow_swappable<_H1>,
1371 : __is_nothrow_swappable<_Equal>>::value)
1372 : {
1373 : // The only base class with member variables is hash_code_base.
1374 : // We define _Hash_code_base::_M_swap because different
1375 : // specializations have different members.
1376 : this->_M_swap(__x);
1377 :
1378 : std::__alloc_on_swap(this->_M_node_allocator(), __x._M_node_allocator());
1379 : std::swap(_M_rehash_policy, __x._M_rehash_policy);
1380 :
1381 : // Deal properly with potentially moved instances.
1382 : if (this->_M_uses_single_bucket())
1383 : {
1384 : if (!__x._M_uses_single_bucket())
1385 : {
1386 : _M_buckets = __x._M_buckets;
1387 : __x._M_buckets = &__x._M_single_bucket;
1388 : }
1389 : }
1390 : else if (__x._M_uses_single_bucket())
1391 : {
1392 : __x._M_buckets = _M_buckets;
1393 : _M_buckets = &_M_single_bucket;
1394 : }
1395 : else
1396 : std::swap(_M_buckets, __x._M_buckets);
1397 :
1398 : std::swap(_M_bucket_count, __x._M_bucket_count);
1399 : std::swap(_M_before_begin._M_nxt, __x._M_before_begin._M_nxt);
1400 : std::swap(_M_element_count, __x._M_element_count);
1401 : std::swap(_M_single_bucket, __x._M_single_bucket);
1402 :
1403 : // Fix buckets containing the _M_before_begin pointers that can't be
1404 : // swapped.
1405 : if (_M_begin())
1406 : _M_buckets[_M_bucket_index(_M_begin())] = &_M_before_begin;
1407 :
1408 : if (__x._M_begin())
1409 : __x._M_buckets[__x._M_bucket_index(__x._M_begin())]
1410 : = &__x._M_before_begin;
1411 : }
1412 :
1413 : template<typename _Key, typename _Value,
1414 : typename _Alloc, typename _ExtractKey, typename _Equal,
1415 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1416 : typename _Traits>
1417 : auto
1418 10 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1419 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1420 : find(const key_type& __k)
1421 : -> iterator
1422 : {
1423 10 : __hash_code __code = this->_M_hash_code(__k);
1424 10 : std::size_t __n = _M_bucket_index(__k, __code);
1425 10 : __node_type* __p = _M_find_node(__n, __k, __code);
1426 10 : return __p ? iterator(__p) : end();
1427 : }
1428 :
1429 : template<typename _Key, typename _Value,
1430 : typename _Alloc, typename _ExtractKey, typename _Equal,
1431 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1432 : typename _Traits>
1433 : auto
1434 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1435 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1436 : find(const key_type& __k) const
1437 : -> const_iterator
1438 : {
1439 : __hash_code __code = this->_M_hash_code(__k);
1440 : std::size_t __n = _M_bucket_index(__k, __code);
1441 : __node_type* __p = _M_find_node(__n, __k, __code);
1442 : return __p ? const_iterator(__p) : end();
1443 : }
1444 :
1445 : template<typename _Key, typename _Value,
1446 : typename _Alloc, typename _ExtractKey, typename _Equal,
1447 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1448 : typename _Traits>
1449 : auto
1450 202 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1451 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1452 : count(const key_type& __k) const
1453 : -> size_type
1454 : {
1455 202 : __hash_code __code = this->_M_hash_code(__k);
1456 202 : std::size_t __n = _M_bucket_index(__k, __code);
1457 202 : __node_type* __p = _M_bucket_begin(__n);
1458 202 : if (!__p)
1459 86 : return 0;
1460 :
1461 116 : std::size_t __result = 0;
1462 0 : for (;; __p = __p->_M_next())
1463 : {
1464 116 : if (this->_M_equals(__k, __code, __p))
1465 0 : ++__result;
1466 116 : else if (__result)
1467 : // All equivalent values are next to each other, if we
1468 : // found a non-equivalent value after an equivalent one it
1469 : // means that we won't find any new equivalent value.
1470 0 : break;
1471 116 : if (!__p->_M_nxt || _M_bucket_index(__p->_M_next()) != __n)
1472 116 : break;
1473 : }
1474 116 : return __result;
1475 : }
1476 :
1477 : template<typename _Key, typename _Value,
1478 : typename _Alloc, typename _ExtractKey, typename _Equal,
1479 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1480 : typename _Traits>
1481 : auto
1482 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1483 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1484 : equal_range(const key_type& __k)
1485 : -> pair<iterator, iterator>
1486 : {
1487 : __hash_code __code = this->_M_hash_code(__k);
1488 : std::size_t __n = _M_bucket_index(__k, __code);
1489 : __node_type* __p = _M_find_node(__n, __k, __code);
1490 :
1491 : if (__p)
1492 : {
1493 : __node_type* __p1 = __p->_M_next();
1494 : while (__p1 && _M_bucket_index(__p1) == __n
1495 : && this->_M_equals(__k, __code, __p1))
1496 : __p1 = __p1->_M_next();
1497 :
1498 : return std::make_pair(iterator(__p), iterator(__p1));
1499 : }
1500 : else
1501 : return std::make_pair(end(), end());
1502 : }
1503 :
1504 : template<typename _Key, typename _Value,
1505 : typename _Alloc, typename _ExtractKey, typename _Equal,
1506 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1507 : typename _Traits>
1508 : auto
1509 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1510 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1511 : equal_range(const key_type& __k) const
1512 : -> pair<const_iterator, const_iterator>
1513 : {
1514 : __hash_code __code = this->_M_hash_code(__k);
1515 : std::size_t __n = _M_bucket_index(__k, __code);
1516 : __node_type* __p = _M_find_node(__n, __k, __code);
1517 :
1518 : if (__p)
1519 : {
1520 : __node_type* __p1 = __p->_M_next();
1521 : while (__p1 && _M_bucket_index(__p1) == __n
1522 : && this->_M_equals(__k, __code, __p1))
1523 : __p1 = __p1->_M_next();
1524 :
1525 : return std::make_pair(const_iterator(__p), const_iterator(__p1));
1526 : }
1527 : else
1528 : return std::make_pair(end(), end());
1529 : }
1530 :
1531 : // Find the node whose key compares equal to k in the bucket n.
1532 : // Return nullptr if no node is found.
1533 : template<typename _Key, typename _Value,
1534 : typename _Alloc, typename _ExtractKey, typename _Equal,
1535 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1536 : typename _Traits>
1537 : auto
1538 1411 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1539 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1540 : _M_find_before_node(size_type __n, const key_type& __k,
1541 : __hash_code __code) const
1542 : -> __node_base*
1543 : {
1544 1411 : __node_base* __prev_p = _M_buckets[__n];
1545 1411 : if (!__prev_p)
1546 1201 : return nullptr;
1547 :
1548 210 : for (__node_type* __p = static_cast<__node_type*>(__prev_p->_M_nxt);;
1549 : __p = __p->_M_next())
1550 : {
1551 210 : if (this->_M_equals(__k, __code, __p))
1552 210 : return __prev_p;
1553 :
1554 0 : if (!__p->_M_nxt || _M_bucket_index(__p->_M_next()) != __n)
1555 0 : break;
1556 0 : __prev_p = __p;
1557 : }
1558 0 : return nullptr;
1559 : }
1560 :
1561 : template<typename _Key, typename _Value,
1562 : typename _Alloc, typename _ExtractKey, typename _Equal,
1563 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1564 : typename _Traits>
1565 : void
1566 1201 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1567 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1568 : _M_insert_bucket_begin(size_type __bkt, __node_type* __node)
1569 : {
1570 1201 : if (_M_buckets[__bkt])
1571 : {
1572 : // Bucket is not empty, we just need to insert the new node
1573 : // after the bucket before begin.
1574 0 : __node->_M_nxt = _M_buckets[__bkt]->_M_nxt;
1575 0 : _M_buckets[__bkt]->_M_nxt = __node;
1576 : }
1577 : else
1578 : {
1579 : // The bucket is empty, the new node is inserted at the
1580 : // beginning of the singly-linked list and the bucket will
1581 : // contain _M_before_begin pointer.
1582 1201 : __node->_M_nxt = _M_before_begin._M_nxt;
1583 1201 : _M_before_begin._M_nxt = __node;
1584 1201 : if (__node->_M_nxt)
1585 : // We must update former begin bucket that is pointing to
1586 : // _M_before_begin.
1587 1185 : _M_buckets[_M_bucket_index(__node->_M_next())] = __node;
1588 1201 : _M_buckets[__bkt] = &_M_before_begin;
1589 : }
1590 1201 : }
1591 :
1592 : template<typename _Key, typename _Value,
1593 : typename _Alloc, typename _ExtractKey, typename _Equal,
1594 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1595 : typename _Traits>
1596 : void
1597 0 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1598 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1599 : _M_remove_bucket_begin(size_type __bkt, __node_type* __next,
1600 : size_type __next_bkt)
1601 : {
1602 0 : if (!__next || __next_bkt != __bkt)
1603 : {
1604 : // Bucket is now empty
1605 : // First update next bucket if any
1606 0 : if (__next)
1607 0 : _M_buckets[__next_bkt] = _M_buckets[__bkt];
1608 :
1609 : // Second update before begin node if necessary
1610 0 : if (&_M_before_begin == _M_buckets[__bkt])
1611 0 : _M_before_begin._M_nxt = __next;
1612 0 : _M_buckets[__bkt] = nullptr;
1613 : }
1614 0 : }
1615 :
1616 : template<typename _Key, typename _Value,
1617 : typename _Alloc, typename _ExtractKey, typename _Equal,
1618 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1619 : typename _Traits>
1620 : auto
1621 0 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1622 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1623 : _M_get_previous_node(size_type __bkt, __node_base* __n)
1624 : -> __node_base*
1625 : {
1626 0 : __node_base* __prev_n = _M_buckets[__bkt];
1627 0 : while (__prev_n->_M_nxt != __n)
1628 0 : __prev_n = __prev_n->_M_nxt;
1629 0 : return __prev_n;
1630 : }
1631 :
1632 : template<typename _Key, typename _Value,
1633 : typename _Alloc, typename _ExtractKey, typename _Equal,
1634 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1635 : typename _Traits>
1636 : template<typename... _Args>
1637 : auto
1638 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1639 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1640 : _M_emplace(std::true_type, _Args&&... __args)
1641 : -> pair<iterator, bool>
1642 : {
1643 : // First build the node to get access to the hash code
1644 : __node_type* __node = this->_M_allocate_node(std::forward<_Args>(__args)...);
1645 : const key_type& __k = this->_M_extract()(__node->_M_v());
1646 : __hash_code __code;
1647 : __try
1648 : {
1649 : __code = this->_M_hash_code(__k);
1650 : }
1651 : __catch(...)
1652 : {
1653 : this->_M_deallocate_node(__node);
1654 : __throw_exception_again;
1655 : }
1656 :
1657 : size_type __bkt = _M_bucket_index(__k, __code);
1658 : if (__node_type* __p = _M_find_node(__bkt, __k, __code))
1659 : {
1660 : // There is already an equivalent node, no insertion
1661 : this->_M_deallocate_node(__node);
1662 : return std::make_pair(iterator(__p), false);
1663 : }
1664 :
1665 : // Insert the node
1666 : return std::make_pair(_M_insert_unique_node(__bkt, __code, __node),
1667 : true);
1668 : }
1669 :
1670 : template<typename _Key, typename _Value,
1671 : typename _Alloc, typename _ExtractKey, typename _Equal,
1672 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1673 : typename _Traits>
1674 : template<typename... _Args>
1675 : auto
1676 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1677 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1678 : _M_emplace(const_iterator __hint, std::false_type, _Args&&... __args)
1679 : -> iterator
1680 : {
1681 : // First build the node to get its hash code.
1682 : __node_type* __node =
1683 : this->_M_allocate_node(std::forward<_Args>(__args)...);
1684 :
1685 : __hash_code __code;
1686 : __try
1687 : {
1688 : __code = this->_M_hash_code(this->_M_extract()(__node->_M_v()));
1689 : }
1690 : __catch(...)
1691 : {
1692 : this->_M_deallocate_node(__node);
1693 : __throw_exception_again;
1694 : }
1695 :
1696 : return _M_insert_multi_node(__hint._M_cur, __code, __node);
1697 : }
1698 :
1699 : template<typename _Key, typename _Value,
1700 : typename _Alloc, typename _ExtractKey, typename _Equal,
1701 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1702 : typename _Traits>
1703 : auto
1704 1201 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1705 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1706 : _M_insert_unique_node(size_type __bkt, __hash_code __code,
1707 : __node_type* __node)
1708 : -> iterator
1709 : {
1710 1201 : const __rehash_state& __saved_state = _M_rehash_policy._M_state();
1711 1201 : std::pair<bool, std::size_t> __do_rehash
1712 : = _M_rehash_policy._M_need_rehash(_M_bucket_count, _M_element_count, 1);
1713 :
1714 : __try
1715 : {
1716 1201 : if (__do_rehash.first)
1717 : {
1718 85 : _M_rehash(__do_rehash.second, __saved_state);
1719 85 : __bkt = _M_bucket_index(this->_M_extract()(__node->_M_v()), __code);
1720 : }
1721 :
1722 1201 : this->_M_store_code(__node, __code);
1723 :
1724 : // Always insert at the beginning of the bucket.
1725 1201 : _M_insert_bucket_begin(__bkt, __node);
1726 1201 : ++_M_element_count;
1727 1201 : return iterator(__node);
1728 : }
1729 0 : __catch(...)
1730 : {
1731 0 : this->_M_deallocate_node(__node);
1732 0 : __throw_exception_again;
1733 : }
1734 : }
1735 :
1736 : // Insert node, in bucket bkt if no rehash (assumes no element with its key
1737 : // already present). Take ownership of the node, deallocate it on exception.
1738 : template<typename _Key, typename _Value,
1739 : typename _Alloc, typename _ExtractKey, typename _Equal,
1740 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1741 : typename _Traits>
1742 : auto
1743 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1744 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1745 : _M_insert_multi_node(__node_type* __hint, __hash_code __code,
1746 : __node_type* __node)
1747 : -> iterator
1748 : {
1749 : const __rehash_state& __saved_state = _M_rehash_policy._M_state();
1750 : std::pair<bool, std::size_t> __do_rehash
1751 : = _M_rehash_policy._M_need_rehash(_M_bucket_count, _M_element_count, 1);
1752 :
1753 : __try
1754 : {
1755 : if (__do_rehash.first)
1756 : _M_rehash(__do_rehash.second, __saved_state);
1757 :
1758 : this->_M_store_code(__node, __code);
1759 : const key_type& __k = this->_M_extract()(__node->_M_v());
1760 : size_type __bkt = _M_bucket_index(__k, __code);
1761 :
1762 : // Find the node before an equivalent one or use hint if it exists and
1763 : // if it is equivalent.
1764 : __node_base* __prev
1765 : = __builtin_expect(__hint != nullptr, false)
1766 : && this->_M_equals(__k, __code, __hint)
1767 : ? __hint
1768 : : _M_find_before_node(__bkt, __k, __code);
1769 : if (__prev)
1770 : {
1771 : // Insert after the node before the equivalent one.
1772 : __node->_M_nxt = __prev->_M_nxt;
1773 : __prev->_M_nxt = __node;
1774 : if (__builtin_expect(__prev == __hint, false))
1775 : // hint might be the last bucket node, in this case we need to
1776 : // update next bucket.
1777 : if (__node->_M_nxt
1778 : && !this->_M_equals(__k, __code, __node->_M_next()))
1779 : {
1780 : size_type __next_bkt = _M_bucket_index(__node->_M_next());
1781 : if (__next_bkt != __bkt)
1782 : _M_buckets[__next_bkt] = __node;
1783 : }
1784 : }
1785 : else
1786 : // The inserted node has no equivalent in the
1787 : // hashtable. We must insert the new node at the
1788 : // beginning of the bucket to preserve equivalent
1789 : // elements' relative positions.
1790 : _M_insert_bucket_begin(__bkt, __node);
1791 : ++_M_element_count;
1792 : return iterator(__node);
1793 : }
1794 : __catch(...)
1795 : {
1796 : this->_M_deallocate_node(__node);
1797 : __throw_exception_again;
1798 : }
1799 : }
1800 :
1801 : // Insert v if no element with its key is already present.
1802 : template<typename _Key, typename _Value,
1803 : typename _Alloc, typename _ExtractKey, typename _Equal,
1804 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1805 : typename _Traits>
1806 : template<typename _Arg, typename _NodeGenerator>
1807 : auto
1808 7 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1809 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1810 : _M_insert(_Arg&& __v, const _NodeGenerator& __node_gen, std::true_type)
1811 : -> pair<iterator, bool>
1812 : {
1813 7 : const key_type& __k = this->_M_extract()(__v);
1814 7 : __hash_code __code = this->_M_hash_code(__k);
1815 7 : size_type __bkt = _M_bucket_index(__k, __code);
1816 :
1817 7 : __node_type* __n = _M_find_node(__bkt, __k, __code);
1818 7 : if (__n)
1819 0 : return std::make_pair(iterator(__n), false);
1820 :
1821 7 : __n = __node_gen(std::forward<_Arg>(__v));
1822 7 : return std::make_pair(_M_insert_unique_node(__bkt, __code, __n), true);
1823 : }
1824 :
1825 : // Insert v unconditionally.
1826 : template<typename _Key, typename _Value,
1827 : typename _Alloc, typename _ExtractKey, typename _Equal,
1828 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1829 : typename _Traits>
1830 : template<typename _Arg, typename _NodeGenerator>
1831 : auto
1832 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1833 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1834 : _M_insert(const_iterator __hint, _Arg&& __v,
1835 : const _NodeGenerator& __node_gen, std::false_type)
1836 : -> iterator
1837 : {
1838 : // First compute the hash code so that we don't do anything if it
1839 : // throws.
1840 : __hash_code __code = this->_M_hash_code(this->_M_extract()(__v));
1841 :
1842 : // Second allocate new node so that we don't rehash if it throws.
1843 : __node_type* __node = __node_gen(std::forward<_Arg>(__v));
1844 :
1845 : return _M_insert_multi_node(__hint._M_cur, __code, __node);
1846 : }
1847 :
1848 : template<typename _Key, typename _Value,
1849 : typename _Alloc, typename _ExtractKey, typename _Equal,
1850 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1851 : typename _Traits>
1852 : auto
1853 0 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1854 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1855 : erase(const_iterator __it)
1856 : -> iterator
1857 : {
1858 0 : __node_type* __n = __it._M_cur;
1859 0 : std::size_t __bkt = _M_bucket_index(__n);
1860 :
1861 : // Look for previous node to unlink it from the erased one, this
1862 : // is why we need buckets to contain the before begin to make
1863 : // this search fast.
1864 0 : __node_base* __prev_n = _M_get_previous_node(__bkt, __n);
1865 0 : return _M_erase(__bkt, __prev_n, __n);
1866 : }
1867 :
1868 : template<typename _Key, typename _Value,
1869 : typename _Alloc, typename _ExtractKey, typename _Equal,
1870 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1871 : typename _Traits>
1872 : auto
1873 0 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1874 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1875 : _M_erase(size_type __bkt, __node_base* __prev_n, __node_type* __n)
1876 : -> iterator
1877 : {
1878 0 : if (__prev_n == _M_buckets[__bkt])
1879 0 : _M_remove_bucket_begin(__bkt, __n->_M_next(),
1880 0 : __n->_M_nxt ? _M_bucket_index(__n->_M_next()) : 0);
1881 0 : else if (__n->_M_nxt)
1882 : {
1883 0 : size_type __next_bkt = _M_bucket_index(__n->_M_next());
1884 0 : if (__next_bkt != __bkt)
1885 0 : _M_buckets[__next_bkt] = __prev_n;
1886 : }
1887 :
1888 0 : __prev_n->_M_nxt = __n->_M_nxt;
1889 0 : iterator __result(__n->_M_next());
1890 0 : this->_M_deallocate_node(__n);
1891 0 : --_M_element_count;
1892 :
1893 0 : return __result;
1894 : }
1895 :
1896 : template<typename _Key, typename _Value,
1897 : typename _Alloc, typename _ExtractKey, typename _Equal,
1898 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1899 : typename _Traits>
1900 : auto
1901 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1902 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1903 : _M_erase(std::true_type, const key_type& __k)
1904 : -> size_type
1905 : {
1906 : __hash_code __code = this->_M_hash_code(__k);
1907 : std::size_t __bkt = _M_bucket_index(__k, __code);
1908 :
1909 : // Look for the node before the first matching node.
1910 : __node_base* __prev_n = _M_find_before_node(__bkt, __k, __code);
1911 : if (!__prev_n)
1912 : return 0;
1913 :
1914 : // We found a matching node, erase it.
1915 : __node_type* __n = static_cast<__node_type*>(__prev_n->_M_nxt);
1916 : _M_erase(__bkt, __prev_n, __n);
1917 : return 1;
1918 : }
1919 :
1920 : template<typename _Key, typename _Value,
1921 : typename _Alloc, typename _ExtractKey, typename _Equal,
1922 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1923 : typename _Traits>
1924 : auto
1925 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1926 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1927 : _M_erase(std::false_type, const key_type& __k)
1928 : -> size_type
1929 : {
1930 : __hash_code __code = this->_M_hash_code(__k);
1931 : std::size_t __bkt = _M_bucket_index(__k, __code);
1932 :
1933 : // Look for the node before the first matching node.
1934 : __node_base* __prev_n = _M_find_before_node(__bkt, __k, __code);
1935 : if (!__prev_n)
1936 : return 0;
1937 :
1938 : // _GLIBCXX_RESOLVE_LIB_DEFECTS
1939 : // 526. Is it undefined if a function in the standard changes
1940 : // in parameters?
1941 : // We use one loop to find all matching nodes and another to deallocate
1942 : // them so that the key stays valid during the first loop. It might be
1943 : // invalidated indirectly when destroying nodes.
1944 : __node_type* __n = static_cast<__node_type*>(__prev_n->_M_nxt);
1945 : __node_type* __n_last = __n;
1946 : std::size_t __n_last_bkt = __bkt;
1947 : do
1948 : {
1949 : __n_last = __n_last->_M_next();
1950 : if (!__n_last)
1951 : break;
1952 : __n_last_bkt = _M_bucket_index(__n_last);
1953 : }
1954 : while (__n_last_bkt == __bkt && this->_M_equals(__k, __code, __n_last));
1955 :
1956 : // Deallocate nodes.
1957 : size_type __result = 0;
1958 : do
1959 : {
1960 : __node_type* __p = __n->_M_next();
1961 : this->_M_deallocate_node(__n);
1962 : __n = __p;
1963 : ++__result;
1964 : --_M_element_count;
1965 : }
1966 : while (__n != __n_last);
1967 :
1968 : if (__prev_n == _M_buckets[__bkt])
1969 : _M_remove_bucket_begin(__bkt, __n_last, __n_last_bkt);
1970 : else if (__n_last && __n_last_bkt != __bkt)
1971 : _M_buckets[__n_last_bkt] = __prev_n;
1972 : __prev_n->_M_nxt = __n_last;
1973 : return __result;
1974 : }
1975 :
1976 : template<typename _Key, typename _Value,
1977 : typename _Alloc, typename _ExtractKey, typename _Equal,
1978 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1979 : typename _Traits>
1980 : auto
1981 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1982 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1983 : erase(const_iterator __first, const_iterator __last)
1984 : -> iterator
1985 : {
1986 : __node_type* __n = __first._M_cur;
1987 : __node_type* __last_n = __last._M_cur;
1988 : if (__n == __last_n)
1989 : return iterator(__n);
1990 :
1991 : std::size_t __bkt = _M_bucket_index(__n);
1992 :
1993 : __node_base* __prev_n = _M_get_previous_node(__bkt, __n);
1994 : bool __is_bucket_begin = __n == _M_bucket_begin(__bkt);
1995 : std::size_t __n_bkt = __bkt;
1996 : for (;;)
1997 : {
1998 : do
1999 : {
2000 : __node_type* __tmp = __n;
2001 : __n = __n->_M_next();
2002 : this->_M_deallocate_node(__tmp);
2003 : --_M_element_count;
2004 : if (!__n)
2005 : break;
2006 : __n_bkt = _M_bucket_index(__n);
2007 : }
2008 : while (__n != __last_n && __n_bkt == __bkt);
2009 : if (__is_bucket_begin)
2010 : _M_remove_bucket_begin(__bkt, __n, __n_bkt);
2011 : if (__n == __last_n)
2012 : break;
2013 : __is_bucket_begin = true;
2014 : __bkt = __n_bkt;
2015 : }
2016 :
2017 : if (__n && (__n_bkt != __bkt || __is_bucket_begin))
2018 : _M_buckets[__n_bkt] = __prev_n;
2019 : __prev_n->_M_nxt = __n;
2020 : return iterator(__n);
2021 : }
2022 :
2023 : template<typename _Key, typename _Value,
2024 : typename _Alloc, typename _ExtractKey, typename _Equal,
2025 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
2026 : typename _Traits>
2027 : void
2028 21 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
2029 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
2030 : clear() noexcept
2031 : {
2032 21 : this->_M_deallocate_nodes(_M_begin());
2033 21 : __builtin_memset(_M_buckets, 0, _M_bucket_count * sizeof(__bucket_type));
2034 21 : _M_element_count = 0;
2035 21 : _M_before_begin._M_nxt = nullptr;
2036 21 : }
2037 :
2038 : template<typename _Key, typename _Value,
2039 : typename _Alloc, typename _ExtractKey, typename _Equal,
2040 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
2041 : typename _Traits>
2042 : void
2043 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
2044 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
2045 : rehash(size_type __n)
2046 : {
2047 : const __rehash_state& __saved_state = _M_rehash_policy._M_state();
2048 : std::size_t __buckets
2049 : = std::max(_M_rehash_policy._M_bkt_for_elements(_M_element_count + 1),
2050 : __n);
2051 : __buckets = _M_rehash_policy._M_next_bkt(__buckets);
2052 :
2053 : if (__buckets != _M_bucket_count)
2054 : _M_rehash(__buckets, __saved_state);
2055 : else
2056 : // No rehash, restore previous state to keep a consistent state.
2057 : _M_rehash_policy._M_reset(__saved_state);
2058 : }
2059 :
2060 : template<typename _Key, typename _Value,
2061 : typename _Alloc, typename _ExtractKey, typename _Equal,
2062 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
2063 : typename _Traits>
2064 : void
2065 85 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
2066 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
2067 : _M_rehash(size_type __n, const __rehash_state& __state)
2068 : {
2069 : __try
2070 : {
2071 85 : _M_rehash_aux(__n, __unique_keys());
2072 : }
2073 0 : __catch(...)
2074 : {
2075 : // A failure here means that buckets allocation failed. We only
2076 : // have to restore hash policy previous state.
2077 0 : _M_rehash_policy._M_reset(__state);
2078 0 : __throw_exception_again;
2079 : }
2080 85 : }
2081 :
2082 : // Rehash when there is no equivalent elements.
2083 : template<typename _Key, typename _Value,
2084 : typename _Alloc, typename _ExtractKey, typename _Equal,
2085 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
2086 : typename _Traits>
2087 : void
2088 85 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
2089 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
2090 : _M_rehash_aux(size_type __n, std::true_type)
2091 : {
2092 85 : __bucket_type* __new_buckets = _M_allocate_buckets(__n);
2093 85 : __node_type* __p = _M_begin();
2094 85 : _M_before_begin._M_nxt = nullptr;
2095 85 : std::size_t __bbegin_bkt = 0;
2096 3445 : while (__p)
2097 : {
2098 1680 : __node_type* __next = __p->_M_next();
2099 1680 : std::size_t __bkt = __hash_code_base::_M_bucket_index(__p, __n);
2100 1680 : if (!__new_buckets[__bkt])
2101 : {
2102 1680 : __p->_M_nxt = _M_before_begin._M_nxt;
2103 1680 : _M_before_begin._M_nxt = __p;
2104 1680 : __new_buckets[__bkt] = &_M_before_begin;
2105 1680 : if (__p->_M_nxt)
2106 1610 : __new_buckets[__bbegin_bkt] = __p;
2107 1680 : __bbegin_bkt = __bkt;
2108 : }
2109 : else
2110 : {
2111 0 : __p->_M_nxt = __new_buckets[__bkt]->_M_nxt;
2112 0 : __new_buckets[__bkt]->_M_nxt = __p;
2113 : }
2114 1680 : __p = __next;
2115 : }
2116 :
2117 85 : _M_deallocate_buckets();
2118 85 : _M_bucket_count = __n;
2119 85 : _M_buckets = __new_buckets;
2120 85 : }
2121 :
2122 : // Rehash when there can be equivalent elements, preserve their relative
2123 : // order.
2124 : template<typename _Key, typename _Value,
2125 : typename _Alloc, typename _ExtractKey, typename _Equal,
2126 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
2127 : typename _Traits>
2128 : void
2129 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
2130 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
2131 : _M_rehash_aux(size_type __n, std::false_type)
2132 : {
2133 : __bucket_type* __new_buckets = _M_allocate_buckets(__n);
2134 :
2135 : __node_type* __p = _M_begin();
2136 : _M_before_begin._M_nxt = nullptr;
2137 : std::size_t __bbegin_bkt = 0;
2138 : std::size_t __prev_bkt = 0;
2139 : __node_type* __prev_p = nullptr;
2140 : bool __check_bucket = false;
2141 :
2142 : while (__p)
2143 : {
2144 : __node_type* __next = __p->_M_next();
2145 : std::size_t __bkt = __hash_code_base::_M_bucket_index(__p, __n);
2146 :
2147 : if (__prev_p && __prev_bkt == __bkt)
2148 : {
2149 : // Previous insert was already in this bucket, we insert after
2150 : // the previously inserted one to preserve equivalent elements
2151 : // relative order.
2152 : __p->_M_nxt = __prev_p->_M_nxt;
2153 : __prev_p->_M_nxt = __p;
2154 :
2155 : // Inserting after a node in a bucket require to check that we
2156 : // haven't change the bucket last node, in this case next
2157 : // bucket containing its before begin node must be updated. We
2158 : // schedule a check as soon as we move out of the sequence of
2159 : // equivalent nodes to limit the number of checks.
2160 : __check_bucket = true;
2161 : }
2162 : else
2163 : {
2164 : if (__check_bucket)
2165 : {
2166 : // Check if we shall update the next bucket because of
2167 : // insertions into __prev_bkt bucket.
2168 : if (__prev_p->_M_nxt)
2169 : {
2170 : std::size_t __next_bkt
2171 : = __hash_code_base::_M_bucket_index(__prev_p->_M_next(),
2172 : __n);
2173 : if (__next_bkt != __prev_bkt)
2174 : __new_buckets[__next_bkt] = __prev_p;
2175 : }
2176 : __check_bucket = false;
2177 : }
2178 :
2179 : if (!__new_buckets[__bkt])
2180 : {
2181 : __p->_M_nxt = _M_before_begin._M_nxt;
2182 : _M_before_begin._M_nxt = __p;
2183 : __new_buckets[__bkt] = &_M_before_begin;
2184 : if (__p->_M_nxt)
2185 : __new_buckets[__bbegin_bkt] = __p;
2186 : __bbegin_bkt = __bkt;
2187 : }
2188 : else
2189 : {
2190 : __p->_M_nxt = __new_buckets[__bkt]->_M_nxt;
2191 : __new_buckets[__bkt]->_M_nxt = __p;
2192 : }
2193 : }
2194 : __prev_p = __p;
2195 : __prev_bkt = __bkt;
2196 : __p = __next;
2197 : }
2198 :
2199 : if (__check_bucket && __prev_p->_M_nxt)
2200 : {
2201 : std::size_t __next_bkt
2202 : = __hash_code_base::_M_bucket_index(__prev_p->_M_next(), __n);
2203 : if (__next_bkt != __prev_bkt)
2204 : __new_buckets[__next_bkt] = __prev_p;
2205 : }
2206 :
2207 : _M_deallocate_buckets();
2208 : _M_bucket_count = __n;
2209 : _M_buckets = __new_buckets;
2210 : }
2211 :
2212 : #if __cplusplus > 201402L
2213 : template<typename, typename, typename> class _Hash_merge_helper { };
2214 : #endif // C++17
2215 :
2216 : _GLIBCXX_END_NAMESPACE_VERSION
2217 : } // namespace std
2218 :
2219 : #endif // _HASHTABLE_H
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