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1 : // hashtable.h header -*- C++ -*-
2 :
3 : // Copyright (C) 2007-2018 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 : __is_nothrow_invocable<const _Hash&, const _Tp&>>>;
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 : static_assert(is_same<typename remove_cv<_Value>::type, _Value>::value,
190 : "unordered container must have a non-const, non-volatile value_type");
191 : #ifdef __STRICT_ANSI__
192 : static_assert(is_same<typename _Alloc::value_type, _Value>{},
193 : "unordered container must have the same value_type as its allocator");
194 : #endif
195 :
196 : using __traits_type = _Traits;
197 : using __hash_cached = typename __traits_type::__hash_cached;
198 : using __node_type = __detail::_Hash_node<_Value, __hash_cached::value>;
199 : using __node_alloc_type = __alloc_rebind<_Alloc, __node_type>;
200 :
201 : using __hashtable_alloc = __detail::_Hashtable_alloc<__node_alloc_type>;
202 :
203 : using __value_alloc_traits =
204 : typename __hashtable_alloc::__value_alloc_traits;
205 : using __node_alloc_traits =
206 : typename __hashtable_alloc::__node_alloc_traits;
207 : using __node_base = typename __hashtable_alloc::__node_base;
208 : using __bucket_type = typename __hashtable_alloc::__bucket_type;
209 :
210 : public:
211 : typedef _Key key_type;
212 : typedef _Value value_type;
213 : typedef _Alloc allocator_type;
214 : typedef _Equal key_equal;
215 :
216 : // mapped_type, if present, comes from _Map_base.
217 : // hasher, if present, comes from _Hash_code_base/_Hashtable_base.
218 : typedef typename __value_alloc_traits::pointer pointer;
219 : typedef typename __value_alloc_traits::const_pointer const_pointer;
220 : typedef value_type& reference;
221 : typedef const value_type& const_reference;
222 :
223 : private:
224 : using __rehash_type = _RehashPolicy;
225 : using __rehash_state = typename __rehash_type::_State;
226 :
227 : using __constant_iterators = typename __traits_type::__constant_iterators;
228 : using __unique_keys = typename __traits_type::__unique_keys;
229 :
230 : using __key_extract = typename std::conditional<
231 : __constant_iterators::value,
232 : __detail::_Identity,
233 : __detail::_Select1st>::type;
234 :
235 : using __hashtable_base = __detail::
236 : _Hashtable_base<_Key, _Value, _ExtractKey,
237 : _Equal, _H1, _H2, _Hash, _Traits>;
238 :
239 : using __hash_code_base = typename __hashtable_base::__hash_code_base;
240 : using __hash_code = typename __hashtable_base::__hash_code;
241 : using __ireturn_type = typename __hashtable_base::__ireturn_type;
242 :
243 : using __map_base = __detail::_Map_base<_Key, _Value, _Alloc, _ExtractKey,
244 : _Equal, _H1, _H2, _Hash,
245 : _RehashPolicy, _Traits>;
246 :
247 : using __rehash_base = __detail::_Rehash_base<_Key, _Value, _Alloc,
248 : _ExtractKey, _Equal,
249 : _H1, _H2, _Hash,
250 : _RehashPolicy, _Traits>;
251 :
252 : using __eq_base = __detail::_Equality<_Key, _Value, _Alloc, _ExtractKey,
253 : _Equal, _H1, _H2, _Hash,
254 : _RehashPolicy, _Traits>;
255 :
256 : using __reuse_or_alloc_node_type =
257 : __detail::_ReuseOrAllocNode<__node_alloc_type>;
258 :
259 : // Metaprogramming for picking apart hash caching.
260 : template<typename _Cond>
261 : using __if_hash_cached = __or_<__not_<__hash_cached>, _Cond>;
262 :
263 : template<typename _Cond>
264 : using __if_hash_not_cached = __or_<__hash_cached, _Cond>;
265 :
266 : // Compile-time diagnostics.
267 :
268 : // _Hash_code_base has everything protected, so use this derived type to
269 : // access it.
270 : struct __hash_code_base_access : __hash_code_base
271 : { using __hash_code_base::_M_bucket_index; };
272 :
273 : // Getting a bucket index from a node shall not throw because it is used
274 : // in methods (erase, swap...) that shall not throw.
275 : static_assert(noexcept(declval<const __hash_code_base_access&>()
276 : ._M_bucket_index((const __node_type*)nullptr,
277 : (std::size_t)0)),
278 : "Cache the hash code or qualify your functors involved"
279 : " in hash code and bucket index computation with noexcept");
280 :
281 : // Following two static assertions are necessary to guarantee
282 : // that local_iterator will be default constructible.
283 :
284 : // When hash codes are cached local iterator inherits from H2 functor
285 : // which must then be default constructible.
286 : static_assert(__if_hash_cached<is_default_constructible<_H2>>::value,
287 : "Functor used to map hash code to bucket index"
288 : " must be default constructible");
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 : bool _Unique_keysa>
295 : friend struct __detail::_Map_base;
296 :
297 : template<typename _Keya, typename _Valuea, typename _Alloca,
298 : typename _ExtractKeya, typename _Equala,
299 : typename _H1a, typename _H2a, typename _Hasha,
300 : typename _RehashPolicya, typename _Traitsa>
301 : friend struct __detail::_Insert_base;
302 :
303 : template<typename _Keya, typename _Valuea, typename _Alloca,
304 : typename _ExtractKeya, typename _Equala,
305 : typename _H1a, typename _H2a, typename _Hasha,
306 : typename _RehashPolicya, typename _Traitsa,
307 : bool _Constant_iteratorsa>
308 : friend struct __detail::_Insert;
309 :
310 : public:
311 : using size_type = typename __hashtable_base::size_type;
312 : using difference_type = typename __hashtable_base::difference_type;
313 :
314 : using iterator = typename __hashtable_base::iterator;
315 : using const_iterator = typename __hashtable_base::const_iterator;
316 :
317 : using local_iterator = typename __hashtable_base::local_iterator;
318 : using const_local_iterator = typename __hashtable_base::
319 : const_local_iterator;
320 :
321 : #if __cplusplus > 201402L
322 : using node_type = _Node_handle<_Key, _Value, __node_alloc_type>;
323 : using insert_return_type = _Node_insert_return<iterator, node_type>;
324 : #endif
325 :
326 : private:
327 : __bucket_type* _M_buckets = &_M_single_bucket;
328 : size_type _M_bucket_count = 1;
329 : __node_base _M_before_begin;
330 : size_type _M_element_count = 0;
331 : _RehashPolicy _M_rehash_policy;
332 :
333 : // A single bucket used when only need for 1 bucket. Especially
334 : // interesting in move semantic to leave hashtable with only 1 buckets
335 : // which is not allocated so that we can have those operations noexcept
336 : // qualified.
337 : // Note that we can't leave hashtable with 0 bucket without adding
338 : // numerous checks in the code to avoid 0 modulus.
339 : __bucket_type _M_single_bucket = nullptr;
340 :
341 : bool
342 4703 : _M_uses_single_bucket(__bucket_type* __bkts) const
343 4703 : { return __builtin_expect(__bkts == &_M_single_bucket, false); }
344 :
345 : bool
346 338 : _M_uses_single_bucket() const
347 338 : { return _M_uses_single_bucket(_M_buckets); }
348 :
349 : __hashtable_alloc&
350 0 : _M_base_alloc() { return *this; }
351 :
352 : __bucket_type*
353 1809 : _M_allocate_buckets(size_type __n)
354 : {
355 1809 : if (__builtin_expect(__n == 1, false))
356 : {
357 0 : _M_single_bucket = nullptr;
358 0 : return &_M_single_bucket;
359 : }
360 :
361 1809 : return __hashtable_alloc::_M_allocate_buckets(__n);
362 : }
363 :
364 : void
365 4365 : _M_deallocate_buckets(__bucket_type* __bkts, size_type __n)
366 : {
367 4365 : if (_M_uses_single_bucket(__bkts))
368 2556 : return;
369 :
370 1809 : __hashtable_alloc::_M_deallocate_buckets(__bkts, __n);
371 : }
372 :
373 : void
374 4365 : _M_deallocate_buckets()
375 4365 : { _M_deallocate_buckets(_M_buckets, _M_bucket_count); }
376 :
377 : // Gets bucket begin, deals with the fact that non-empty buckets contain
378 : // their before begin node.
379 : __node_type*
380 : _M_bucket_begin(size_type __bkt) const;
381 :
382 : __node_type*
383 5354 : _M_begin() const
384 5354 : { return static_cast<__node_type*>(_M_before_begin._M_nxt); }
385 :
386 : template<typename _NodeGenerator>
387 : void
388 : _M_assign(const _Hashtable&, const _NodeGenerator&);
389 :
390 : void
391 : _M_move_assign(_Hashtable&&, std::true_type);
392 :
393 : void
394 : _M_move_assign(_Hashtable&&, std::false_type);
395 :
396 : void
397 : _M_reset() noexcept;
398 :
399 : _Hashtable(const _H1& __h1, const _H2& __h2, const _Hash& __h,
400 : const _Equal& __eq, const _ExtractKey& __exk,
401 : const allocator_type& __a)
402 : : __hashtable_base(__exk, __h1, __h2, __h, __eq),
403 : __hashtable_alloc(__node_alloc_type(__a))
404 : { }
405 :
406 : public:
407 : // Constructor, destructor, assignment, swap
408 2218 : _Hashtable() = default;
409 : _Hashtable(size_type __bucket_hint,
410 : const _H1&, const _H2&, const _Hash&,
411 : const _Equal&, const _ExtractKey&,
412 : const allocator_type&);
413 :
414 : template<typename _InputIterator>
415 : _Hashtable(_InputIterator __first, _InputIterator __last,
416 : size_type __bucket_hint,
417 : const _H1&, const _H2&, const _Hash&,
418 : const _Equal&, const _ExtractKey&,
419 : const allocator_type&);
420 :
421 : _Hashtable(const _Hashtable&);
422 :
423 : _Hashtable(_Hashtable&&) noexcept;
424 :
425 : _Hashtable(const _Hashtable&, const allocator_type&);
426 :
427 : _Hashtable(_Hashtable&&, const allocator_type&);
428 :
429 : // Use delegating constructors.
430 : explicit
431 : _Hashtable(const allocator_type& __a)
432 : : __hashtable_alloc(__node_alloc_type(__a))
433 : { }
434 :
435 : explicit
436 : _Hashtable(size_type __n,
437 : const _H1& __hf = _H1(),
438 : const key_equal& __eql = key_equal(),
439 : const allocator_type& __a = allocator_type())
440 : : _Hashtable(__n, __hf, _H2(), _Hash(), __eql,
441 : __key_extract(), __a)
442 : { }
443 :
444 : template<typename _InputIterator>
445 : _Hashtable(_InputIterator __f, _InputIterator __l,
446 : size_type __n = 0,
447 : const _H1& __hf = _H1(),
448 : const key_equal& __eql = key_equal(),
449 : const allocator_type& __a = allocator_type())
450 : : _Hashtable(__f, __l, __n, __hf, _H2(), _Hash(), __eql,
451 : __key_extract(), __a)
452 : { }
453 :
454 : _Hashtable(initializer_list<value_type> __l,
455 : size_type __n = 0,
456 : const _H1& __hf = _H1(),
457 : const key_equal& __eql = key_equal(),
458 : const allocator_type& __a = allocator_type())
459 : : _Hashtable(__l.begin(), __l.end(), __n, __hf, _H2(), _Hash(), __eql,
460 : __key_extract(), __a)
461 : { }
462 :
463 : _Hashtable&
464 : operator=(const _Hashtable& __ht);
465 :
466 : _Hashtable&
467 338 : operator=(_Hashtable&& __ht)
468 : noexcept(__node_alloc_traits::_S_nothrow_move()
469 : && is_nothrow_move_assignable<_H1>::value
470 : && is_nothrow_move_assignable<_Equal>::value)
471 : {
472 338 : constexpr bool __move_storage =
473 : __node_alloc_traits::_S_propagate_on_move_assign()
474 : || __node_alloc_traits::_S_always_equal();
475 338 : _M_move_assign(std::move(__ht), __bool_constant<__move_storage>());
476 338 : return *this;
477 : }
478 :
479 : _Hashtable&
480 : operator=(initializer_list<value_type> __l)
481 : {
482 : __reuse_or_alloc_node_type __roan(_M_begin(), *this);
483 : _M_before_begin._M_nxt = nullptr;
484 : clear();
485 : this->_M_insert_range(__l.begin(), __l.end(), __roan, __unique_keys());
486 : return *this;
487 : }
488 :
489 : ~_Hashtable() noexcept;
490 :
491 : void
492 : swap(_Hashtable&)
493 : noexcept(__and_<__is_nothrow_swappable<_H1>,
494 : __is_nothrow_swappable<_Equal>>::value);
495 :
496 : // Basic container operations
497 : iterator
498 301 : begin() noexcept
499 301 : { return iterator(_M_begin()); }
500 :
501 : const_iterator
502 16 : begin() const noexcept
503 16 : { return const_iterator(_M_begin()); }
504 :
505 : iterator
506 23561 : end() noexcept
507 23561 : { return iterator(nullptr); }
508 :
509 : const_iterator
510 35 : end() const noexcept
511 35 : { return const_iterator(nullptr); }
512 :
513 : const_iterator
514 : cbegin() const noexcept
515 : { return const_iterator(_M_begin()); }
516 :
517 : const_iterator
518 : cend() const noexcept
519 : { return const_iterator(nullptr); }
520 :
521 : size_type
522 514 : size() const noexcept
523 514 : { return _M_element_count; }
524 :
525 : bool
526 370 : empty() const noexcept
527 370 : { return size() == 0; }
528 :
529 : allocator_type
530 : get_allocator() const noexcept
531 : { return allocator_type(this->_M_node_allocator()); }
532 :
533 : size_type
534 : max_size() const noexcept
535 : { return __node_alloc_traits::max_size(this->_M_node_allocator()); }
536 :
537 : // Observers
538 : key_equal
539 : key_eq() const
540 : { return this->_M_eq(); }
541 :
542 : // hash_function, if present, comes from _Hash_code_base.
543 :
544 : // Bucket operations
545 : size_type
546 : bucket_count() const noexcept
547 : { return _M_bucket_count; }
548 :
549 : size_type
550 : max_bucket_count() const noexcept
551 : { return max_size(); }
552 :
553 : size_type
554 : bucket_size(size_type __n) const
555 : { return std::distance(begin(__n), end(__n)); }
556 :
557 : size_type
558 : bucket(const key_type& __k) const
559 : { return _M_bucket_index(__k, this->_M_hash_code(__k)); }
560 :
561 : local_iterator
562 : begin(size_type __n)
563 : {
564 : return local_iterator(*this, _M_bucket_begin(__n),
565 : __n, _M_bucket_count);
566 : }
567 :
568 : local_iterator
569 : end(size_type __n)
570 : { return local_iterator(*this, nullptr, __n, _M_bucket_count); }
571 :
572 : const_local_iterator
573 : begin(size_type __n) const
574 : {
575 : return const_local_iterator(*this, _M_bucket_begin(__n),
576 : __n, _M_bucket_count);
577 : }
578 :
579 : const_local_iterator
580 : end(size_type __n) const
581 : { return const_local_iterator(*this, nullptr, __n, _M_bucket_count); }
582 :
583 : // DR 691.
584 : const_local_iterator
585 : cbegin(size_type __n) const
586 : {
587 : return const_local_iterator(*this, _M_bucket_begin(__n),
588 : __n, _M_bucket_count);
589 : }
590 :
591 : const_local_iterator
592 : cend(size_type __n) const
593 : { return const_local_iterator(*this, nullptr, __n, _M_bucket_count); }
594 :
595 : float
596 : load_factor() const noexcept
597 : {
598 : return static_cast<float>(size()) / static_cast<float>(bucket_count());
599 : }
600 :
601 : // max_load_factor, if present, comes from _Rehash_base.
602 :
603 : // Generalization of max_load_factor. Extension, not found in
604 : // TR1. Only useful if _RehashPolicy is something other than
605 : // the default.
606 : const _RehashPolicy&
607 : __rehash_policy() const
608 : { return _M_rehash_policy; }
609 :
610 : void
611 : __rehash_policy(const _RehashPolicy& __pol)
612 : { _M_rehash_policy = __pol; }
613 :
614 : // Lookup.
615 : iterator
616 : find(const key_type& __k);
617 :
618 : const_iterator
619 : find(const key_type& __k) const;
620 :
621 : size_type
622 : count(const key_type& __k) const;
623 :
624 : std::pair<iterator, iterator>
625 : equal_range(const key_type& __k);
626 :
627 : std::pair<const_iterator, const_iterator>
628 : equal_range(const key_type& __k) const;
629 :
630 : protected:
631 : // Bucket index computation helpers.
632 : size_type
633 5967 : _M_bucket_index(__node_type* __n) const noexcept
634 5967 : { return __hash_code_base::_M_bucket_index(__n, _M_bucket_count); }
635 :
636 : size_type
637 29825 : _M_bucket_index(const key_type& __k, __hash_code __c) const
638 29825 : { return __hash_code_base::_M_bucket_index(__k, __c, _M_bucket_count); }
639 :
640 : // Find and insert helper functions and types
641 : // Find the node before the one matching the criteria.
642 : __node_base*
643 : _M_find_before_node(size_type, const key_type&, __hash_code) const;
644 :
645 : __node_type*
646 27647 : _M_find_node(size_type __bkt, const key_type& __key,
647 : __hash_code __c) const
648 : {
649 27647 : __node_base* __before_n = _M_find_before_node(__bkt, __key, __c);
650 27647 : if (__before_n)
651 17927 : return static_cast<__node_type*>(__before_n->_M_nxt);
652 9720 : return nullptr;
653 : }
654 :
655 : // Insert a node at the beginning of a bucket.
656 : void
657 : _M_insert_bucket_begin(size_type, __node_type*);
658 :
659 : // Remove the bucket first node
660 : void
661 : _M_remove_bucket_begin(size_type __bkt, __node_type* __next_n,
662 : size_type __next_bkt);
663 :
664 : // Get the node before __n in the bucket __bkt
665 : __node_base*
666 : _M_get_previous_node(size_type __bkt, __node_base* __n);
667 :
668 : // Insert node with hash code __code, in bucket bkt if no rehash (assumes
669 : // no element with its key already present). Take ownership of the node,
670 : // deallocate it on exception.
671 : iterator
672 : _M_insert_unique_node(size_type __bkt, __hash_code __code,
673 : __node_type* __n, size_type __n_elt = 1);
674 :
675 : // Insert node with hash code __code. Take ownership of the node,
676 : // deallocate it on exception.
677 : iterator
678 : _M_insert_multi_node(__node_type* __hint,
679 : __hash_code __code, __node_type* __n);
680 :
681 : template<typename... _Args>
682 : std::pair<iterator, bool>
683 : _M_emplace(std::true_type, _Args&&... __args);
684 :
685 : template<typename... _Args>
686 : iterator
687 : _M_emplace(std::false_type __uk, _Args&&... __args)
688 : { return _M_emplace(cend(), __uk, std::forward<_Args>(__args)...); }
689 :
690 : // Emplace with hint, useless when keys are unique.
691 : template<typename... _Args>
692 : iterator
693 : _M_emplace(const_iterator, std::true_type __uk, _Args&&... __args)
694 : { return _M_emplace(__uk, std::forward<_Args>(__args)...).first; }
695 :
696 : template<typename... _Args>
697 : iterator
698 : _M_emplace(const_iterator, std::false_type, _Args&&... __args);
699 :
700 : template<typename _Arg, typename _NodeGenerator>
701 : std::pair<iterator, bool>
702 : _M_insert(_Arg&&, const _NodeGenerator&, true_type, size_type = 1);
703 :
704 : template<typename _Arg, typename _NodeGenerator>
705 : iterator
706 : _M_insert(_Arg&& __arg, const _NodeGenerator& __node_gen,
707 : false_type __uk)
708 : {
709 : return _M_insert(cend(), std::forward<_Arg>(__arg), __node_gen,
710 : __uk);
711 : }
712 :
713 : // Insert with hint, not used when keys are unique.
714 : template<typename _Arg, typename _NodeGenerator>
715 : iterator
716 : _M_insert(const_iterator, _Arg&& __arg,
717 : const _NodeGenerator& __node_gen, true_type __uk)
718 : {
719 : return
720 : _M_insert(std::forward<_Arg>(__arg), __node_gen, __uk).first;
721 : }
722 :
723 : // Insert with hint when keys are not unique.
724 : template<typename _Arg, typename _NodeGenerator>
725 : iterator
726 : _M_insert(const_iterator, _Arg&&,
727 : const _NodeGenerator&, false_type);
728 :
729 : size_type
730 : _M_erase(std::true_type, const key_type&);
731 :
732 : size_type
733 : _M_erase(std::false_type, const key_type&);
734 :
735 : iterator
736 : _M_erase(size_type __bkt, __node_base* __prev_n, __node_type* __n);
737 :
738 : public:
739 : // Emplace
740 : template<typename... _Args>
741 : __ireturn_type
742 : emplace(_Args&&... __args)
743 : { return _M_emplace(__unique_keys(), std::forward<_Args>(__args)...); }
744 :
745 : template<typename... _Args>
746 : iterator
747 : emplace_hint(const_iterator __hint, _Args&&... __args)
748 : {
749 : return _M_emplace(__hint, __unique_keys(),
750 : std::forward<_Args>(__args)...);
751 : }
752 :
753 : // Insert member functions via inheritance.
754 :
755 : // Erase
756 : iterator
757 : erase(const_iterator);
758 :
759 : // LWG 2059.
760 : iterator
761 157 : erase(iterator __it)
762 157 : { return erase(const_iterator(__it)); }
763 :
764 : size_type
765 369 : erase(const key_type& __k)
766 369 : { return _M_erase(__unique_keys(), __k); }
767 :
768 : iterator
769 : erase(const_iterator, const_iterator);
770 :
771 : void
772 : clear() noexcept;
773 :
774 : // Set number of buckets to be appropriate for container of n element.
775 : void rehash(size_type __n);
776 :
777 : // DR 1189.
778 : // reserve, if present, comes from _Rehash_base.
779 :
780 : #if __cplusplus > 201402L
781 : /// Re-insert an extracted node into a container with unique keys.
782 : insert_return_type
783 : _M_reinsert_node(node_type&& __nh)
784 : {
785 : insert_return_type __ret;
786 : if (__nh.empty())
787 : __ret.position = end();
788 : else
789 : {
790 : __glibcxx_assert(get_allocator() == __nh.get_allocator());
791 :
792 : const key_type& __k = __nh._M_key();
793 : __hash_code __code = this->_M_hash_code(__k);
794 : size_type __bkt = _M_bucket_index(__k, __code);
795 : if (__node_type* __n = _M_find_node(__bkt, __k, __code))
796 : {
797 : __ret.node = std::move(__nh);
798 : __ret.position = iterator(__n);
799 : __ret.inserted = false;
800 : }
801 : else
802 : {
803 : __ret.position
804 : = _M_insert_unique_node(__bkt, __code, __nh._M_ptr);
805 : __nh._M_ptr = nullptr;
806 : __ret.inserted = true;
807 : }
808 : }
809 : return __ret;
810 : }
811 :
812 : /// Re-insert an extracted node into a container with equivalent keys.
813 : iterator
814 : _M_reinsert_node_multi(const_iterator __hint, node_type&& __nh)
815 : {
816 : iterator __ret;
817 : if (__nh.empty())
818 : __ret = end();
819 : else
820 : {
821 : __glibcxx_assert(get_allocator() == __nh.get_allocator());
822 :
823 : auto __code = this->_M_hash_code(__nh._M_key());
824 : auto __node = std::exchange(__nh._M_ptr, nullptr);
825 : // FIXME: this deallocates the node on exception.
826 : __ret = _M_insert_multi_node(__hint._M_cur, __code, __node);
827 : }
828 : return __ret;
829 : }
830 :
831 : /// Extract a node.
832 : node_type
833 176 : extract(const_iterator __pos)
834 : {
835 176 : __node_type* __n = __pos._M_cur;
836 176 : size_t __bkt = _M_bucket_index(__n);
837 :
838 : // Look for previous node to unlink it from the erased one, this
839 : // is why we need buckets to contain the before begin to make
840 : // this search fast.
841 176 : __node_base* __prev_n = _M_get_previous_node(__bkt, __n);
842 :
843 176 : if (__prev_n == _M_buckets[__bkt])
844 176 : _M_remove_bucket_begin(__bkt, __n->_M_next(),
845 176 : __n->_M_nxt ? _M_bucket_index(__n->_M_next()) : 0);
846 0 : else if (__n->_M_nxt)
847 : {
848 0 : size_type __next_bkt = _M_bucket_index(__n->_M_next());
849 0 : if (__next_bkt != __bkt)
850 0 : _M_buckets[__next_bkt] = __prev_n;
851 : }
852 :
853 176 : __prev_n->_M_nxt = __n->_M_nxt;
854 176 : __n->_M_nxt = nullptr;
855 176 : --_M_element_count;
856 176 : return { __n, this->_M_node_allocator() };
857 : }
858 :
859 : /// Extract a node.
860 : node_type
861 : extract(const _Key& __k)
862 : {
863 : node_type __nh;
864 : auto __pos = find(__k);
865 : if (__pos != end())
866 : __nh = extract(const_iterator(__pos));
867 : return __nh;
868 : }
869 :
870 : /// Merge from a compatible container into one with unique keys.
871 : template<typename _Compatible_Hashtable>
872 : void
873 144 : _M_merge_unique(_Compatible_Hashtable& __src) noexcept
874 : {
875 : static_assert(is_same_v<typename _Compatible_Hashtable::node_type,
876 : node_type>, "Node types are compatible");
877 : __glibcxx_assert(get_allocator() == __src.get_allocator());
878 :
879 144 : auto __n_elt = __src.size();
880 320 : for (auto __i = __src.begin(), __end = __src.end(); __i != __end;)
881 : {
882 176 : auto __pos = __i++;
883 176 : const key_type& __k = this->_M_extract()(__pos._M_cur->_M_v());
884 176 : __hash_code __code = this->_M_hash_code(__k);
885 176 : size_type __bkt = _M_bucket_index(__k, __code);
886 176 : if (_M_find_node(__bkt, __k, __code) == nullptr)
887 : {
888 176 : auto __nh = __src.extract(__pos);
889 176 : _M_insert_unique_node(__bkt, __code, __nh._M_ptr, __n_elt);
890 176 : __nh._M_ptr = nullptr;
891 176 : __n_elt = 1;
892 : }
893 0 : else if (__n_elt != 1)
894 0 : --__n_elt;
895 : }
896 144 : }
897 :
898 : /// Merge from a compatible container into one with equivalent keys.
899 : template<typename _Compatible_Hashtable>
900 : void
901 : _M_merge_multi(_Compatible_Hashtable& __src) noexcept
902 : {
903 : static_assert(is_same_v<typename _Compatible_Hashtable::node_type,
904 : node_type>, "Node types are compatible");
905 : __glibcxx_assert(get_allocator() == __src.get_allocator());
906 :
907 : this->reserve(size() + __src.size());
908 : for (auto __i = __src.begin(), __end = __src.end(); __i != __end;)
909 : _M_reinsert_node_multi(cend(), __src.extract(__i++));
910 : }
911 : #endif // C++17
912 :
913 : private:
914 : // Helper rehash method used when keys are unique.
915 : void _M_rehash_aux(size_type __n, std::true_type);
916 :
917 : // Helper rehash method used when keys can be non-unique.
918 : void _M_rehash_aux(size_type __n, std::false_type);
919 :
920 : // Unconditionally change size of bucket array to n, restore
921 : // hash policy state to __state on exception.
922 : void _M_rehash(size_type __n, const __rehash_state& __state);
923 : };
924 :
925 :
926 : // Definitions of class template _Hashtable's out-of-line member functions.
927 : template<typename _Key, typename _Value,
928 : typename _Alloc, typename _ExtractKey, typename _Equal,
929 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
930 : typename _Traits>
931 : auto
932 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
933 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
934 : _M_bucket_begin(size_type __bkt) const
935 : -> __node_type*
936 : {
937 : __node_base* __n = _M_buckets[__bkt];
938 : return __n ? static_cast<__node_type*>(__n->_M_nxt) : nullptr;
939 : }
940 :
941 : template<typename _Key, typename _Value,
942 : typename _Alloc, typename _ExtractKey, typename _Equal,
943 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
944 : typename _Traits>
945 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
946 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
947 : _Hashtable(size_type __bucket_hint,
948 : const _H1& __h1, const _H2& __h2, const _Hash& __h,
949 : const _Equal& __eq, const _ExtractKey& __exk,
950 : const allocator_type& __a)
951 : : _Hashtable(__h1, __h2, __h, __eq, __exk, __a)
952 : {
953 : auto __bkt = _M_rehash_policy._M_next_bkt(__bucket_hint);
954 : if (__bkt > _M_bucket_count)
955 : {
956 : _M_buckets = _M_allocate_buckets(__bkt);
957 : _M_bucket_count = __bkt;
958 : }
959 : }
960 :
961 : template<typename _Key, typename _Value,
962 : typename _Alloc, typename _ExtractKey, typename _Equal,
963 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
964 : typename _Traits>
965 : template<typename _InputIterator>
966 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
967 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
968 : _Hashtable(_InputIterator __f, _InputIterator __l,
969 : size_type __bucket_hint,
970 : const _H1& __h1, const _H2& __h2, const _Hash& __h,
971 : const _Equal& __eq, const _ExtractKey& __exk,
972 : const allocator_type& __a)
973 : : _Hashtable(__h1, __h2, __h, __eq, __exk, __a)
974 : {
975 : auto __nb_elems = __detail::__distance_fw(__f, __l);
976 : auto __bkt_count =
977 : _M_rehash_policy._M_next_bkt(
978 : std::max(_M_rehash_policy._M_bkt_for_elements(__nb_elems),
979 : __bucket_hint));
980 :
981 : if (__bkt_count > _M_bucket_count)
982 : {
983 : _M_buckets = _M_allocate_buckets(__bkt_count);
984 : _M_bucket_count = __bkt_count;
985 : }
986 :
987 : for (; __f != __l; ++__f)
988 : this->insert(*__f);
989 : }
990 :
991 : template<typename _Key, typename _Value,
992 : typename _Alloc, typename _ExtractKey, typename _Equal,
993 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
994 : typename _Traits>
995 : auto
996 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
997 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
998 : operator=(const _Hashtable& __ht)
999 : -> _Hashtable&
1000 : {
1001 : if (&__ht == this)
1002 : return *this;
1003 :
1004 : if (__node_alloc_traits::_S_propagate_on_copy_assign())
1005 : {
1006 : auto& __this_alloc = this->_M_node_allocator();
1007 : auto& __that_alloc = __ht._M_node_allocator();
1008 : if (!__node_alloc_traits::_S_always_equal()
1009 : && __this_alloc != __that_alloc)
1010 : {
1011 : // Replacement allocator cannot free existing storage.
1012 : this->_M_deallocate_nodes(_M_begin());
1013 : _M_before_begin._M_nxt = nullptr;
1014 : _M_deallocate_buckets();
1015 : _M_buckets = nullptr;
1016 : std::__alloc_on_copy(__this_alloc, __that_alloc);
1017 : __hashtable_base::operator=(__ht);
1018 : _M_bucket_count = __ht._M_bucket_count;
1019 : _M_element_count = __ht._M_element_count;
1020 : _M_rehash_policy = __ht._M_rehash_policy;
1021 : __try
1022 : {
1023 : _M_assign(__ht,
1024 : [this](const __node_type* __n)
1025 : { return this->_M_allocate_node(__n->_M_v()); });
1026 : }
1027 : __catch(...)
1028 : {
1029 : // _M_assign took care of deallocating all memory. Now we
1030 : // must make sure this instance remains in a usable state.
1031 : _M_reset();
1032 : __throw_exception_again;
1033 : }
1034 : return *this;
1035 : }
1036 : std::__alloc_on_copy(__this_alloc, __that_alloc);
1037 : }
1038 :
1039 : // Reuse allocated buckets and nodes.
1040 : __bucket_type* __former_buckets = nullptr;
1041 : std::size_t __former_bucket_count = _M_bucket_count;
1042 : const __rehash_state& __former_state = _M_rehash_policy._M_state();
1043 :
1044 : if (_M_bucket_count != __ht._M_bucket_count)
1045 : {
1046 : __former_buckets = _M_buckets;
1047 : _M_buckets = _M_allocate_buckets(__ht._M_bucket_count);
1048 : _M_bucket_count = __ht._M_bucket_count;
1049 : }
1050 : else
1051 : __builtin_memset(_M_buckets, 0,
1052 : _M_bucket_count * sizeof(__bucket_type));
1053 :
1054 : __try
1055 : {
1056 : __hashtable_base::operator=(__ht);
1057 : _M_element_count = __ht._M_element_count;
1058 : _M_rehash_policy = __ht._M_rehash_policy;
1059 : __reuse_or_alloc_node_type __roan(_M_begin(), *this);
1060 : _M_before_begin._M_nxt = nullptr;
1061 : _M_assign(__ht,
1062 : [&__roan](const __node_type* __n)
1063 : { return __roan(__n->_M_v()); });
1064 : if (__former_buckets)
1065 : _M_deallocate_buckets(__former_buckets, __former_bucket_count);
1066 : }
1067 : __catch(...)
1068 : {
1069 : if (__former_buckets)
1070 : {
1071 : // Restore previous buckets.
1072 : _M_deallocate_buckets();
1073 : _M_rehash_policy._M_reset(__former_state);
1074 : _M_buckets = __former_buckets;
1075 : _M_bucket_count = __former_bucket_count;
1076 : }
1077 : __builtin_memset(_M_buckets, 0,
1078 : _M_bucket_count * sizeof(__bucket_type));
1079 : __throw_exception_again;
1080 : }
1081 : return *this;
1082 : }
1083 :
1084 : template<typename _Key, typename _Value,
1085 : typename _Alloc, typename _ExtractKey, typename _Equal,
1086 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1087 : typename _Traits>
1088 : template<typename _NodeGenerator>
1089 : void
1090 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1091 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1092 : _M_assign(const _Hashtable& __ht, const _NodeGenerator& __node_gen)
1093 : {
1094 : __bucket_type* __buckets = nullptr;
1095 : if (!_M_buckets)
1096 : _M_buckets = __buckets = _M_allocate_buckets(_M_bucket_count);
1097 :
1098 : __try
1099 : {
1100 : if (!__ht._M_before_begin._M_nxt)
1101 : return;
1102 :
1103 : // First deal with the special first node pointed to by
1104 : // _M_before_begin.
1105 : __node_type* __ht_n = __ht._M_begin();
1106 : __node_type* __this_n = __node_gen(__ht_n);
1107 : this->_M_copy_code(__this_n, __ht_n);
1108 : _M_before_begin._M_nxt = __this_n;
1109 : _M_buckets[_M_bucket_index(__this_n)] = &_M_before_begin;
1110 :
1111 : // Then deal with other nodes.
1112 : __node_base* __prev_n = __this_n;
1113 : for (__ht_n = __ht_n->_M_next(); __ht_n; __ht_n = __ht_n->_M_next())
1114 : {
1115 : __this_n = __node_gen(__ht_n);
1116 : __prev_n->_M_nxt = __this_n;
1117 : this->_M_copy_code(__this_n, __ht_n);
1118 : size_type __bkt = _M_bucket_index(__this_n);
1119 : if (!_M_buckets[__bkt])
1120 : _M_buckets[__bkt] = __prev_n;
1121 : __prev_n = __this_n;
1122 : }
1123 : }
1124 : __catch(...)
1125 : {
1126 : clear();
1127 : if (__buckets)
1128 : _M_deallocate_buckets();
1129 : __throw_exception_again;
1130 : }
1131 : }
1132 :
1133 : template<typename _Key, typename _Value,
1134 : typename _Alloc, typename _ExtractKey, typename _Equal,
1135 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1136 : typename _Traits>
1137 : void
1138 338 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1139 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1140 : _M_reset() noexcept
1141 : {
1142 338 : _M_rehash_policy._M_reset();
1143 338 : _M_bucket_count = 1;
1144 338 : _M_single_bucket = nullptr;
1145 338 : _M_buckets = &_M_single_bucket;
1146 338 : _M_before_begin._M_nxt = nullptr;
1147 338 : _M_element_count = 0;
1148 338 : }
1149 :
1150 : template<typename _Key, typename _Value,
1151 : typename _Alloc, typename _ExtractKey, typename _Equal,
1152 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1153 : typename _Traits>
1154 : void
1155 338 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1156 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1157 : _M_move_assign(_Hashtable&& __ht, std::true_type)
1158 : {
1159 338 : this->_M_deallocate_nodes(_M_begin());
1160 338 : _M_deallocate_buckets();
1161 338 : __hashtable_base::operator=(std::move(__ht));
1162 338 : _M_rehash_policy = __ht._M_rehash_policy;
1163 338 : if (!__ht._M_uses_single_bucket())
1164 236 : _M_buckets = __ht._M_buckets;
1165 : else
1166 : {
1167 102 : _M_buckets = &_M_single_bucket;
1168 102 : _M_single_bucket = __ht._M_single_bucket;
1169 : }
1170 338 : _M_bucket_count = __ht._M_bucket_count;
1171 338 : _M_before_begin._M_nxt = __ht._M_before_begin._M_nxt;
1172 338 : _M_element_count = __ht._M_element_count;
1173 338 : std::__alloc_on_move(this->_M_node_allocator(), __ht._M_node_allocator());
1174 :
1175 : // Fix buckets containing the _M_before_begin pointers that can't be
1176 : // moved.
1177 338 : if (_M_begin())
1178 236 : _M_buckets[_M_bucket_index(_M_begin())] = &_M_before_begin;
1179 338 : __ht._M_reset();
1180 338 : }
1181 :
1182 : template<typename _Key, typename _Value,
1183 : typename _Alloc, typename _ExtractKey, typename _Equal,
1184 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1185 : typename _Traits>
1186 : void
1187 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1188 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1189 : _M_move_assign(_Hashtable&& __ht, std::false_type)
1190 : {
1191 : if (__ht._M_node_allocator() == this->_M_node_allocator())
1192 : _M_move_assign(std::move(__ht), std::true_type());
1193 : else
1194 : {
1195 : // Can't move memory, move elements then.
1196 : __bucket_type* __former_buckets = nullptr;
1197 : size_type __former_bucket_count = _M_bucket_count;
1198 : const __rehash_state& __former_state = _M_rehash_policy._M_state();
1199 :
1200 : if (_M_bucket_count != __ht._M_bucket_count)
1201 : {
1202 : __former_buckets = _M_buckets;
1203 : _M_buckets = _M_allocate_buckets(__ht._M_bucket_count);
1204 : _M_bucket_count = __ht._M_bucket_count;
1205 : }
1206 : else
1207 : __builtin_memset(_M_buckets, 0,
1208 : _M_bucket_count * sizeof(__bucket_type));
1209 :
1210 : __try
1211 : {
1212 : __hashtable_base::operator=(std::move(__ht));
1213 : _M_element_count = __ht._M_element_count;
1214 : _M_rehash_policy = __ht._M_rehash_policy;
1215 : __reuse_or_alloc_node_type __roan(_M_begin(), *this);
1216 : _M_before_begin._M_nxt = nullptr;
1217 : _M_assign(__ht,
1218 : [&__roan](__node_type* __n)
1219 : { return __roan(std::move_if_noexcept(__n->_M_v())); });
1220 :
1221 : if (__former_buckets)
1222 : _M_deallocate_buckets(__former_buckets, __former_bucket_count);
1223 : __ht.clear();
1224 : }
1225 : __catch(...)
1226 : {
1227 : if (__former_buckets)
1228 : {
1229 : _M_deallocate_buckets();
1230 : _M_rehash_policy._M_reset(__former_state);
1231 : _M_buckets = __former_buckets;
1232 : _M_bucket_count = __former_bucket_count;
1233 : }
1234 : __builtin_memset(_M_buckets, 0,
1235 : _M_bucket_count * sizeof(__bucket_type));
1236 : __throw_exception_again;
1237 : }
1238 : }
1239 : }
1240 :
1241 : template<typename _Key, typename _Value,
1242 : typename _Alloc, typename _ExtractKey, typename _Equal,
1243 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1244 : typename _Traits>
1245 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1246 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1247 : _Hashtable(const _Hashtable& __ht)
1248 : : __hashtable_base(__ht),
1249 : __map_base(__ht),
1250 : __rehash_base(__ht),
1251 : __hashtable_alloc(
1252 : __node_alloc_traits::_S_select_on_copy(__ht._M_node_allocator())),
1253 : _M_buckets(nullptr),
1254 : _M_bucket_count(__ht._M_bucket_count),
1255 : _M_element_count(__ht._M_element_count),
1256 : _M_rehash_policy(__ht._M_rehash_policy)
1257 : {
1258 : _M_assign(__ht,
1259 : [this](const __node_type* __n)
1260 : { return this->_M_allocate_node(__n->_M_v()); });
1261 : }
1262 :
1263 : template<typename _Key, typename _Value,
1264 : typename _Alloc, typename _ExtractKey, typename _Equal,
1265 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1266 : typename _Traits>
1267 0 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1268 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1269 : _Hashtable(_Hashtable&& __ht) noexcept
1270 : : __hashtable_base(__ht),
1271 : __map_base(__ht),
1272 : __rehash_base(__ht),
1273 0 : __hashtable_alloc(std::move(__ht._M_base_alloc())),
1274 0 : _M_buckets(__ht._M_buckets),
1275 0 : _M_bucket_count(__ht._M_bucket_count),
1276 : _M_before_begin(__ht._M_before_begin._M_nxt),
1277 0 : _M_element_count(__ht._M_element_count),
1278 0 : _M_rehash_policy(__ht._M_rehash_policy)
1279 : {
1280 : // Update, if necessary, buckets if __ht is using its single bucket.
1281 0 : if (__ht._M_uses_single_bucket())
1282 : {
1283 0 : _M_buckets = &_M_single_bucket;
1284 0 : _M_single_bucket = __ht._M_single_bucket;
1285 : }
1286 :
1287 : // Update, if necessary, bucket pointing to before begin that hasn't
1288 : // moved.
1289 0 : if (_M_begin())
1290 0 : _M_buckets[_M_bucket_index(_M_begin())] = &_M_before_begin;
1291 :
1292 0 : __ht._M_reset();
1293 0 : }
1294 :
1295 : template<typename _Key, typename _Value,
1296 : typename _Alloc, typename _ExtractKey, typename _Equal,
1297 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1298 : typename _Traits>
1299 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1300 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1301 : _Hashtable(const _Hashtable& __ht, const allocator_type& __a)
1302 : : __hashtable_base(__ht),
1303 : __map_base(__ht),
1304 : __rehash_base(__ht),
1305 : __hashtable_alloc(__node_alloc_type(__a)),
1306 : _M_buckets(),
1307 : _M_bucket_count(__ht._M_bucket_count),
1308 : _M_element_count(__ht._M_element_count),
1309 : _M_rehash_policy(__ht._M_rehash_policy)
1310 : {
1311 : _M_assign(__ht,
1312 : [this](const __node_type* __n)
1313 : { return this->_M_allocate_node(__n->_M_v()); });
1314 : }
1315 :
1316 : template<typename _Key, typename _Value,
1317 : typename _Alloc, typename _ExtractKey, typename _Equal,
1318 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1319 : typename _Traits>
1320 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1321 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1322 : _Hashtable(_Hashtable&& __ht, const allocator_type& __a)
1323 : : __hashtable_base(__ht),
1324 : __map_base(__ht),
1325 : __rehash_base(__ht),
1326 : __hashtable_alloc(__node_alloc_type(__a)),
1327 : _M_buckets(nullptr),
1328 : _M_bucket_count(__ht._M_bucket_count),
1329 : _M_element_count(__ht._M_element_count),
1330 : _M_rehash_policy(__ht._M_rehash_policy)
1331 : {
1332 : if (__ht._M_node_allocator() == this->_M_node_allocator())
1333 : {
1334 : if (__ht._M_uses_single_bucket())
1335 : {
1336 : _M_buckets = &_M_single_bucket;
1337 : _M_single_bucket = __ht._M_single_bucket;
1338 : }
1339 : else
1340 : _M_buckets = __ht._M_buckets;
1341 :
1342 : _M_before_begin._M_nxt = __ht._M_before_begin._M_nxt;
1343 : // Update, if necessary, bucket pointing to before begin that hasn't
1344 : // moved.
1345 : if (_M_begin())
1346 : _M_buckets[_M_bucket_index(_M_begin())] = &_M_before_begin;
1347 : __ht._M_reset();
1348 : }
1349 : else
1350 : {
1351 : _M_assign(__ht,
1352 : [this](__node_type* __n)
1353 : {
1354 : return this->_M_allocate_node(
1355 : std::move_if_noexcept(__n->_M_v()));
1356 : });
1357 : __ht.clear();
1358 : }
1359 : }
1360 :
1361 : template<typename _Key, typename _Value,
1362 : typename _Alloc, typename _ExtractKey, typename _Equal,
1363 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1364 : typename _Traits>
1365 2218 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1366 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1367 : ~_Hashtable() noexcept
1368 : {
1369 2218 : clear();
1370 2218 : _M_deallocate_buckets();
1371 2218 : }
1372 :
1373 : template<typename _Key, typename _Value,
1374 : typename _Alloc, typename _ExtractKey, typename _Equal,
1375 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1376 : typename _Traits>
1377 : void
1378 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1379 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1380 : swap(_Hashtable& __x)
1381 : noexcept(__and_<__is_nothrow_swappable<_H1>,
1382 : __is_nothrow_swappable<_Equal>>::value)
1383 : {
1384 : // The only base class with member variables is hash_code_base.
1385 : // We define _Hash_code_base::_M_swap because different
1386 : // specializations have different members.
1387 : this->_M_swap(__x);
1388 :
1389 : std::__alloc_on_swap(this->_M_node_allocator(), __x._M_node_allocator());
1390 : std::swap(_M_rehash_policy, __x._M_rehash_policy);
1391 :
1392 : // Deal properly with potentially moved instances.
1393 : if (this->_M_uses_single_bucket())
1394 : {
1395 : if (!__x._M_uses_single_bucket())
1396 : {
1397 : _M_buckets = __x._M_buckets;
1398 : __x._M_buckets = &__x._M_single_bucket;
1399 : }
1400 : }
1401 : else if (__x._M_uses_single_bucket())
1402 : {
1403 : __x._M_buckets = _M_buckets;
1404 : _M_buckets = &_M_single_bucket;
1405 : }
1406 : else
1407 : std::swap(_M_buckets, __x._M_buckets);
1408 :
1409 : std::swap(_M_bucket_count, __x._M_bucket_count);
1410 : std::swap(_M_before_begin._M_nxt, __x._M_before_begin._M_nxt);
1411 : std::swap(_M_element_count, __x._M_element_count);
1412 : std::swap(_M_single_bucket, __x._M_single_bucket);
1413 :
1414 : // Fix buckets containing the _M_before_begin pointers that can't be
1415 : // swapped.
1416 : if (_M_begin())
1417 : _M_buckets[_M_bucket_index(_M_begin())] = &_M_before_begin;
1418 :
1419 : if (__x._M_begin())
1420 : __x._M_buckets[__x._M_bucket_index(__x._M_begin())]
1421 : = &__x._M_before_begin;
1422 : }
1423 :
1424 : template<typename _Key, typename _Value,
1425 : typename _Alloc, typename _ExtractKey, typename _Equal,
1426 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1427 : typename _Traits>
1428 : auto
1429 17339 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1430 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1431 : find(const key_type& __k)
1432 : -> iterator
1433 : {
1434 17339 : __hash_code __code = this->_M_hash_code(__k);
1435 17339 : std::size_t __n = _M_bucket_index(__k, __code);
1436 17339 : __node_type* __p = _M_find_node(__n, __k, __code);
1437 17339 : return __p ? iterator(__p) : end();
1438 : }
1439 :
1440 : template<typename _Key, typename _Value,
1441 : typename _Alloc, typename _ExtractKey, typename _Equal,
1442 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1443 : typename _Traits>
1444 : auto
1445 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1446 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1447 : find(const key_type& __k) const
1448 : -> const_iterator
1449 : {
1450 : __hash_code __code = this->_M_hash_code(__k);
1451 : std::size_t __n = _M_bucket_index(__k, __code);
1452 : __node_type* __p = _M_find_node(__n, __k, __code);
1453 : return __p ? const_iterator(__p) : end();
1454 : }
1455 :
1456 : template<typename _Key, typename _Value,
1457 : typename _Alloc, typename _ExtractKey, typename _Equal,
1458 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1459 : typename _Traits>
1460 : auto
1461 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1462 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1463 : count(const key_type& __k) const
1464 : -> size_type
1465 : {
1466 : __hash_code __code = this->_M_hash_code(__k);
1467 : std::size_t __n = _M_bucket_index(__k, __code);
1468 : __node_type* __p = _M_bucket_begin(__n);
1469 : if (!__p)
1470 : return 0;
1471 :
1472 : std::size_t __result = 0;
1473 : for (;; __p = __p->_M_next())
1474 : {
1475 : if (this->_M_equals(__k, __code, __p))
1476 : ++__result;
1477 : else if (__result)
1478 : // All equivalent values are next to each other, if we
1479 : // found a non-equivalent value after an equivalent one it
1480 : // means that we won't find any new equivalent value.
1481 : break;
1482 : if (!__p->_M_nxt || _M_bucket_index(__p->_M_next()) != __n)
1483 : break;
1484 : }
1485 : return __result;
1486 : }
1487 :
1488 : template<typename _Key, typename _Value,
1489 : typename _Alloc, typename _ExtractKey, typename _Equal,
1490 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1491 : typename _Traits>
1492 : auto
1493 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1494 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1495 : equal_range(const key_type& __k)
1496 : -> pair<iterator, iterator>
1497 : {
1498 : __hash_code __code = this->_M_hash_code(__k);
1499 : std::size_t __n = _M_bucket_index(__k, __code);
1500 : __node_type* __p = _M_find_node(__n, __k, __code);
1501 :
1502 : if (__p)
1503 : {
1504 : __node_type* __p1 = __p->_M_next();
1505 : while (__p1 && _M_bucket_index(__p1) == __n
1506 : && this->_M_equals(__k, __code, __p1))
1507 : __p1 = __p1->_M_next();
1508 :
1509 : return std::make_pair(iterator(__p), iterator(__p1));
1510 : }
1511 : else
1512 : return std::make_pair(end(), end());
1513 : }
1514 :
1515 : template<typename _Key, typename _Value,
1516 : typename _Alloc, typename _ExtractKey, typename _Equal,
1517 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1518 : typename _Traits>
1519 : auto
1520 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1521 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1522 : equal_range(const key_type& __k) const
1523 : -> pair<const_iterator, const_iterator>
1524 : {
1525 : __hash_code __code = this->_M_hash_code(__k);
1526 : std::size_t __n = _M_bucket_index(__k, __code);
1527 : __node_type* __p = _M_find_node(__n, __k, __code);
1528 :
1529 : if (__p)
1530 : {
1531 : __node_type* __p1 = __p->_M_next();
1532 : while (__p1 && _M_bucket_index(__p1) == __n
1533 : && this->_M_equals(__k, __code, __p1))
1534 : __p1 = __p1->_M_next();
1535 :
1536 : return std::make_pair(const_iterator(__p), const_iterator(__p1));
1537 : }
1538 : else
1539 : return std::make_pair(end(), end());
1540 : }
1541 :
1542 : // Find the node whose key compares equal to k in the bucket n.
1543 : // Return nullptr if no node is found.
1544 : template<typename _Key, typename _Value,
1545 : typename _Alloc, typename _ExtractKey, typename _Equal,
1546 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1547 : typename _Traits>
1548 : auto
1549 28016 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1550 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1551 : _M_find_before_node(size_type __n, const key_type& __k,
1552 : __hash_code __code) const
1553 : -> __node_base*
1554 : {
1555 28016 : __node_base* __prev_p = _M_buckets[__n];
1556 28016 : if (!__prev_p)
1557 8314 : return nullptr;
1558 :
1559 19702 : for (__node_type* __p = static_cast<__node_type*>(__prev_p->_M_nxt);;
1560 2884 : __p = __p->_M_next())
1561 : {
1562 22586 : if (this->_M_equals(__k, __code, __p))
1563 18011 : return __prev_p;
1564 :
1565 4575 : if (!__p->_M_nxt || _M_bucket_index(__p->_M_next()) != __n)
1566 1691 : break;
1567 2884 : __prev_p = __p;
1568 : }
1569 1691 : return nullptr;
1570 : }
1571 :
1572 : template<typename _Key, typename _Value,
1573 : typename _Alloc, typename _ExtractKey, typename _Equal,
1574 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1575 : typename _Traits>
1576 : void
1577 3799 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1578 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1579 : _M_insert_bucket_begin(size_type __bkt, __node_type* __node)
1580 : {
1581 3799 : if (_M_buckets[__bkt])
1582 : {
1583 : // Bucket is not empty, we just need to insert the new node
1584 : // after the bucket before begin.
1585 650 : __node->_M_nxt = _M_buckets[__bkt]->_M_nxt;
1586 650 : _M_buckets[__bkt]->_M_nxt = __node;
1587 : }
1588 : else
1589 : {
1590 : // The bucket is empty, the new node is inserted at the
1591 : // beginning of the singly-linked list and the bucket will
1592 : // contain _M_before_begin pointer.
1593 3149 : __node->_M_nxt = _M_before_begin._M_nxt;
1594 3149 : _M_before_begin._M_nxt = __node;
1595 3149 : if (__node->_M_nxt)
1596 : // We must update former begin bucket that is pointing to
1597 : // _M_before_begin.
1598 1615 : _M_buckets[_M_bucket_index(__node->_M_next())] = __node;
1599 3149 : _M_buckets[__bkt] = &_M_before_begin;
1600 : }
1601 3799 : }
1602 :
1603 : template<typename _Key, typename _Value,
1604 : typename _Alloc, typename _ExtractKey, typename _Equal,
1605 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1606 : typename _Traits>
1607 : void
1608 411 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1609 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1610 : _M_remove_bucket_begin(size_type __bkt, __node_type* __next,
1611 : size_type __next_bkt)
1612 : {
1613 411 : if (!__next || __next_bkt != __bkt)
1614 : {
1615 : // Bucket is now empty
1616 : // First update next bucket if any
1617 404 : if (__next)
1618 79 : _M_buckets[__next_bkt] = _M_buckets[__bkt];
1619 :
1620 : // Second update before begin node if necessary
1621 404 : if (&_M_before_begin == _M_buckets[__bkt])
1622 329 : _M_before_begin._M_nxt = __next;
1623 404 : _M_buckets[__bkt] = nullptr;
1624 : }
1625 411 : }
1626 :
1627 : template<typename _Key, typename _Value,
1628 : typename _Alloc, typename _ExtractKey, typename _Equal,
1629 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1630 : typename _Traits>
1631 : auto
1632 334 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1633 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1634 : _M_get_previous_node(size_type __bkt, __node_base* __n)
1635 : -> __node_base*
1636 : {
1637 334 : __node_base* __prev_n = _M_buckets[__bkt];
1638 334 : while (__prev_n->_M_nxt != __n)
1639 0 : __prev_n = __prev_n->_M_nxt;
1640 334 : return __prev_n;
1641 : }
1642 :
1643 : template<typename _Key, typename _Value,
1644 : typename _Alloc, typename _ExtractKey, typename _Equal,
1645 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1646 : typename _Traits>
1647 : template<typename... _Args>
1648 : auto
1649 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1650 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1651 : _M_emplace(std::true_type, _Args&&... __args)
1652 : -> pair<iterator, bool>
1653 : {
1654 : // First build the node to get access to the hash code
1655 : __node_type* __node = this->_M_allocate_node(std::forward<_Args>(__args)...);
1656 : const key_type& __k = this->_M_extract()(__node->_M_v());
1657 : __hash_code __code;
1658 : __try
1659 : {
1660 : __code = this->_M_hash_code(__k);
1661 : }
1662 : __catch(...)
1663 : {
1664 : this->_M_deallocate_node(__node);
1665 : __throw_exception_again;
1666 : }
1667 :
1668 : size_type __bkt = _M_bucket_index(__k, __code);
1669 : if (__node_type* __p = _M_find_node(__bkt, __k, __code))
1670 : {
1671 : // There is already an equivalent node, no insertion
1672 : this->_M_deallocate_node(__node);
1673 : return std::make_pair(iterator(__p), false);
1674 : }
1675 :
1676 : // Insert the node
1677 : return std::make_pair(_M_insert_unique_node(__bkt, __code, __node),
1678 : true);
1679 : }
1680 :
1681 : template<typename _Key, typename _Value,
1682 : typename _Alloc, typename _ExtractKey, typename _Equal,
1683 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1684 : typename _Traits>
1685 : template<typename... _Args>
1686 : auto
1687 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1688 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1689 : _M_emplace(const_iterator __hint, std::false_type, _Args&&... __args)
1690 : -> iterator
1691 : {
1692 : // First build the node to get its hash code.
1693 : __node_type* __node =
1694 : this->_M_allocate_node(std::forward<_Args>(__args)...);
1695 :
1696 : __hash_code __code;
1697 : __try
1698 : {
1699 : __code = this->_M_hash_code(this->_M_extract()(__node->_M_v()));
1700 : }
1701 : __catch(...)
1702 : {
1703 : this->_M_deallocate_node(__node);
1704 : __throw_exception_again;
1705 : }
1706 :
1707 : return _M_insert_multi_node(__hint._M_cur, __code, __node);
1708 : }
1709 :
1710 : template<typename _Key, typename _Value,
1711 : typename _Alloc, typename _ExtractKey, typename _Equal,
1712 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1713 : typename _Traits>
1714 : auto
1715 3799 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1716 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1717 : _M_insert_unique_node(size_type __bkt, __hash_code __code,
1718 : __node_type* __node, size_type __n_elt)
1719 : -> iterator
1720 : {
1721 3799 : const __rehash_state& __saved_state = _M_rehash_policy._M_state();
1722 3799 : std::pair<bool, std::size_t> __do_rehash
1723 : = _M_rehash_policy._M_need_rehash(_M_bucket_count, _M_element_count,
1724 : __n_elt);
1725 :
1726 : __try
1727 : {
1728 3799 : if (__do_rehash.first)
1729 : {
1730 1809 : _M_rehash(__do_rehash.second, __saved_state);
1731 1809 : __bkt = _M_bucket_index(this->_M_extract()(__node->_M_v()), __code);
1732 : }
1733 :
1734 3799 : this->_M_store_code(__node, __code);
1735 :
1736 : // Always insert at the beginning of the bucket.
1737 3799 : _M_insert_bucket_begin(__bkt, __node);
1738 3799 : ++_M_element_count;
1739 3799 : return iterator(__node);
1740 : }
1741 0 : __catch(...)
1742 : {
1743 0 : this->_M_deallocate_node(__node);
1744 0 : __throw_exception_again;
1745 : }
1746 : }
1747 :
1748 : // Insert node, in bucket bkt if no rehash (assumes no element with its key
1749 : // already present). Take ownership of the node, deallocate it on exception.
1750 : template<typename _Key, typename _Value,
1751 : typename _Alloc, typename _ExtractKey, typename _Equal,
1752 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1753 : typename _Traits>
1754 : auto
1755 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1756 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1757 : _M_insert_multi_node(__node_type* __hint, __hash_code __code,
1758 : __node_type* __node)
1759 : -> iterator
1760 : {
1761 : const __rehash_state& __saved_state = _M_rehash_policy._M_state();
1762 : std::pair<bool, std::size_t> __do_rehash
1763 : = _M_rehash_policy._M_need_rehash(_M_bucket_count, _M_element_count, 1);
1764 :
1765 : __try
1766 : {
1767 : if (__do_rehash.first)
1768 : _M_rehash(__do_rehash.second, __saved_state);
1769 :
1770 : this->_M_store_code(__node, __code);
1771 : const key_type& __k = this->_M_extract()(__node->_M_v());
1772 : size_type __bkt = _M_bucket_index(__k, __code);
1773 :
1774 : // Find the node before an equivalent one or use hint if it exists and
1775 : // if it is equivalent.
1776 : __node_base* __prev
1777 : = __builtin_expect(__hint != nullptr, false)
1778 : && this->_M_equals(__k, __code, __hint)
1779 : ? __hint
1780 : : _M_find_before_node(__bkt, __k, __code);
1781 : if (__prev)
1782 : {
1783 : // Insert after the node before the equivalent one.
1784 : __node->_M_nxt = __prev->_M_nxt;
1785 : __prev->_M_nxt = __node;
1786 : if (__builtin_expect(__prev == __hint, false))
1787 : // hint might be the last bucket node, in this case we need to
1788 : // update next bucket.
1789 : if (__node->_M_nxt
1790 : && !this->_M_equals(__k, __code, __node->_M_next()))
1791 : {
1792 : size_type __next_bkt = _M_bucket_index(__node->_M_next());
1793 : if (__next_bkt != __bkt)
1794 : _M_buckets[__next_bkt] = __node;
1795 : }
1796 : }
1797 : else
1798 : // The inserted node has no equivalent in the
1799 : // hashtable. We must insert the new node at the
1800 : // beginning of the bucket to preserve equivalent
1801 : // elements' relative positions.
1802 : _M_insert_bucket_begin(__bkt, __node);
1803 : ++_M_element_count;
1804 : return iterator(__node);
1805 : }
1806 : __catch(...)
1807 : {
1808 : this->_M_deallocate_node(__node);
1809 : __throw_exception_again;
1810 : }
1811 : }
1812 :
1813 : // Insert v if no element with its key is already present.
1814 : template<typename _Key, typename _Value,
1815 : typename _Alloc, typename _ExtractKey, typename _Equal,
1816 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1817 : typename _Traits>
1818 : template<typename _Arg, typename _NodeGenerator>
1819 : auto
1820 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1821 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1822 : _M_insert(_Arg&& __v, const _NodeGenerator& __node_gen, true_type,
1823 : size_type __n_elt)
1824 : -> pair<iterator, bool>
1825 : {
1826 : const key_type& __k = this->_M_extract()(__v);
1827 : __hash_code __code = this->_M_hash_code(__k);
1828 : size_type __bkt = _M_bucket_index(__k, __code);
1829 :
1830 : __node_type* __n = _M_find_node(__bkt, __k, __code);
1831 : if (__n)
1832 : return std::make_pair(iterator(__n), false);
1833 :
1834 : __n = __node_gen(std::forward<_Arg>(__v));
1835 : return { _M_insert_unique_node(__bkt, __code, __n, __n_elt), true };
1836 : }
1837 :
1838 : // Insert v unconditionally.
1839 : template<typename _Key, typename _Value,
1840 : typename _Alloc, typename _ExtractKey, typename _Equal,
1841 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1842 : typename _Traits>
1843 : template<typename _Arg, typename _NodeGenerator>
1844 : auto
1845 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1846 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1847 : _M_insert(const_iterator __hint, _Arg&& __v,
1848 : const _NodeGenerator& __node_gen, false_type)
1849 : -> iterator
1850 : {
1851 : // First compute the hash code so that we don't do anything if it
1852 : // throws.
1853 : __hash_code __code = this->_M_hash_code(this->_M_extract()(__v));
1854 :
1855 : // Second allocate new node so that we don't rehash if it throws.
1856 : __node_type* __node = __node_gen(std::forward<_Arg>(__v));
1857 :
1858 : return _M_insert_multi_node(__hint._M_cur, __code, __node);
1859 : }
1860 :
1861 : template<typename _Key, typename _Value,
1862 : typename _Alloc, typename _ExtractKey, typename _Equal,
1863 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1864 : typename _Traits>
1865 : auto
1866 158 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1867 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1868 : erase(const_iterator __it)
1869 : -> iterator
1870 : {
1871 158 : __node_type* __n = __it._M_cur;
1872 158 : std::size_t __bkt = _M_bucket_index(__n);
1873 :
1874 : // Look for previous node to unlink it from the erased one, this
1875 : // is why we need buckets to contain the before begin to make
1876 : // this search fast.
1877 158 : __node_base* __prev_n = _M_get_previous_node(__bkt, __n);
1878 158 : return _M_erase(__bkt, __prev_n, __n);
1879 : }
1880 :
1881 : template<typename _Key, typename _Value,
1882 : typename _Alloc, typename _ExtractKey, typename _Equal,
1883 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1884 : typename _Traits>
1885 : auto
1886 242 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1887 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1888 : _M_erase(size_type __bkt, __node_base* __prev_n, __node_type* __n)
1889 : -> iterator
1890 : {
1891 242 : if (__prev_n == _M_buckets[__bkt])
1892 235 : _M_remove_bucket_begin(__bkt, __n->_M_next(),
1893 235 : __n->_M_nxt ? _M_bucket_index(__n->_M_next()) : 0);
1894 7 : else if (__n->_M_nxt)
1895 : {
1896 6 : size_type __next_bkt = _M_bucket_index(__n->_M_next());
1897 6 : if (__next_bkt != __bkt)
1898 5 : _M_buckets[__next_bkt] = __prev_n;
1899 : }
1900 :
1901 242 : __prev_n->_M_nxt = __n->_M_nxt;
1902 242 : iterator __result(__n->_M_next());
1903 242 : this->_M_deallocate_node(__n);
1904 242 : --_M_element_count;
1905 :
1906 242 : return __result;
1907 : }
1908 :
1909 : template<typename _Key, typename _Value,
1910 : typename _Alloc, typename _ExtractKey, typename _Equal,
1911 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1912 : typename _Traits>
1913 : auto
1914 369 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1915 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1916 : _M_erase(std::true_type, const key_type& __k)
1917 : -> size_type
1918 : {
1919 369 : __hash_code __code = this->_M_hash_code(__k);
1920 369 : std::size_t __bkt = _M_bucket_index(__k, __code);
1921 :
1922 : // Look for the node before the first matching node.
1923 369 : __node_base* __prev_n = _M_find_before_node(__bkt, __k, __code);
1924 369 : if (!__prev_n)
1925 285 : return 0;
1926 :
1927 : // We found a matching node, erase it.
1928 84 : __node_type* __n = static_cast<__node_type*>(__prev_n->_M_nxt);
1929 84 : _M_erase(__bkt, __prev_n, __n);
1930 84 : return 1;
1931 : }
1932 :
1933 : template<typename _Key, typename _Value,
1934 : typename _Alloc, typename _ExtractKey, typename _Equal,
1935 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1936 : typename _Traits>
1937 : auto
1938 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1939 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1940 : _M_erase(std::false_type, const key_type& __k)
1941 : -> size_type
1942 : {
1943 : __hash_code __code = this->_M_hash_code(__k);
1944 : std::size_t __bkt = _M_bucket_index(__k, __code);
1945 :
1946 : // Look for the node before the first matching node.
1947 : __node_base* __prev_n = _M_find_before_node(__bkt, __k, __code);
1948 : if (!__prev_n)
1949 : return 0;
1950 :
1951 : // _GLIBCXX_RESOLVE_LIB_DEFECTS
1952 : // 526. Is it undefined if a function in the standard changes
1953 : // in parameters?
1954 : // We use one loop to find all matching nodes and another to deallocate
1955 : // them so that the key stays valid during the first loop. It might be
1956 : // invalidated indirectly when destroying nodes.
1957 : __node_type* __n = static_cast<__node_type*>(__prev_n->_M_nxt);
1958 : __node_type* __n_last = __n;
1959 : std::size_t __n_last_bkt = __bkt;
1960 : do
1961 : {
1962 : __n_last = __n_last->_M_next();
1963 : if (!__n_last)
1964 : break;
1965 : __n_last_bkt = _M_bucket_index(__n_last);
1966 : }
1967 : while (__n_last_bkt == __bkt && this->_M_equals(__k, __code, __n_last));
1968 :
1969 : // Deallocate nodes.
1970 : size_type __result = 0;
1971 : do
1972 : {
1973 : __node_type* __p = __n->_M_next();
1974 : this->_M_deallocate_node(__n);
1975 : __n = __p;
1976 : ++__result;
1977 : --_M_element_count;
1978 : }
1979 : while (__n != __n_last);
1980 :
1981 : if (__prev_n == _M_buckets[__bkt])
1982 : _M_remove_bucket_begin(__bkt, __n_last, __n_last_bkt);
1983 : else if (__n_last && __n_last_bkt != __bkt)
1984 : _M_buckets[__n_last_bkt] = __prev_n;
1985 : __prev_n->_M_nxt = __n_last;
1986 : return __result;
1987 : }
1988 :
1989 : template<typename _Key, typename _Value,
1990 : typename _Alloc, typename _ExtractKey, typename _Equal,
1991 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
1992 : typename _Traits>
1993 : auto
1994 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
1995 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
1996 : erase(const_iterator __first, const_iterator __last)
1997 : -> iterator
1998 : {
1999 : __node_type* __n = __first._M_cur;
2000 : __node_type* __last_n = __last._M_cur;
2001 : if (__n == __last_n)
2002 : return iterator(__n);
2003 :
2004 : std::size_t __bkt = _M_bucket_index(__n);
2005 :
2006 : __node_base* __prev_n = _M_get_previous_node(__bkt, __n);
2007 : bool __is_bucket_begin = __n == _M_bucket_begin(__bkt);
2008 : std::size_t __n_bkt = __bkt;
2009 : for (;;)
2010 : {
2011 : do
2012 : {
2013 : __node_type* __tmp = __n;
2014 : __n = __n->_M_next();
2015 : this->_M_deallocate_node(__tmp);
2016 : --_M_element_count;
2017 : if (!__n)
2018 : break;
2019 : __n_bkt = _M_bucket_index(__n);
2020 : }
2021 : while (__n != __last_n && __n_bkt == __bkt);
2022 : if (__is_bucket_begin)
2023 : _M_remove_bucket_begin(__bkt, __n, __n_bkt);
2024 : if (__n == __last_n)
2025 : break;
2026 : __is_bucket_begin = true;
2027 : __bkt = __n_bkt;
2028 : }
2029 :
2030 : if (__n && (__n_bkt != __bkt || __is_bucket_begin))
2031 : _M_buckets[__n_bkt] = __prev_n;
2032 : __prev_n->_M_nxt = __n;
2033 : return iterator(__n);
2034 : }
2035 :
2036 : template<typename _Key, typename _Value,
2037 : typename _Alloc, typename _ExtractKey, typename _Equal,
2038 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
2039 : typename _Traits>
2040 : void
2041 2316 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
2042 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
2043 : clear() noexcept
2044 : {
2045 2316 : this->_M_deallocate_nodes(_M_begin());
2046 2316 : __builtin_memset(_M_buckets, 0, _M_bucket_count * sizeof(__bucket_type));
2047 2316 : _M_element_count = 0;
2048 2316 : _M_before_begin._M_nxt = nullptr;
2049 2316 : }
2050 :
2051 : template<typename _Key, typename _Value,
2052 : typename _Alloc, typename _ExtractKey, typename _Equal,
2053 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
2054 : typename _Traits>
2055 : void
2056 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
2057 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
2058 : rehash(size_type __n)
2059 : {
2060 : const __rehash_state& __saved_state = _M_rehash_policy._M_state();
2061 : std::size_t __buckets
2062 : = std::max(_M_rehash_policy._M_bkt_for_elements(_M_element_count + 1),
2063 : __n);
2064 : __buckets = _M_rehash_policy._M_next_bkt(__buckets);
2065 :
2066 : if (__buckets != _M_bucket_count)
2067 : _M_rehash(__buckets, __saved_state);
2068 : else
2069 : // No rehash, restore previous state to keep a consistent state.
2070 : _M_rehash_policy._M_reset(__saved_state);
2071 : }
2072 :
2073 : template<typename _Key, typename _Value,
2074 : typename _Alloc, typename _ExtractKey, typename _Equal,
2075 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
2076 : typename _Traits>
2077 : void
2078 1809 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
2079 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
2080 : _M_rehash(size_type __n, const __rehash_state& __state)
2081 : {
2082 : __try
2083 : {
2084 1809 : _M_rehash_aux(__n, __unique_keys());
2085 : }
2086 0 : __catch(...)
2087 : {
2088 : // A failure here means that buckets allocation failed. We only
2089 : // have to restore hash policy previous state.
2090 0 : _M_rehash_policy._M_reset(__state);
2091 0 : __throw_exception_again;
2092 : }
2093 1809 : }
2094 :
2095 : // Rehash when there is no equivalent elements.
2096 : template<typename _Key, typename _Value,
2097 : typename _Alloc, typename _ExtractKey, typename _Equal,
2098 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
2099 : typename _Traits>
2100 : void
2101 1809 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
2102 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
2103 : _M_rehash_aux(size_type __n, std::true_type)
2104 : {
2105 1809 : __bucket_type* __new_buckets = _M_allocate_buckets(__n);
2106 1809 : __node_type* __p = _M_begin();
2107 1809 : _M_before_begin._M_nxt = nullptr;
2108 1809 : std::size_t __bbegin_bkt = 0;
2109 2997 : while (__p)
2110 : {
2111 1188 : __node_type* __next = __p->_M_next();
2112 1188 : std::size_t __bkt = __hash_code_base::_M_bucket_index(__p, __n);
2113 1188 : if (!__new_buckets[__bkt])
2114 : {
2115 1045 : __p->_M_nxt = _M_before_begin._M_nxt;
2116 1045 : _M_before_begin._M_nxt = __p;
2117 1045 : __new_buckets[__bkt] = &_M_before_begin;
2118 1045 : if (__p->_M_nxt)
2119 724 : __new_buckets[__bbegin_bkt] = __p;
2120 1045 : __bbegin_bkt = __bkt;
2121 : }
2122 : else
2123 : {
2124 143 : __p->_M_nxt = __new_buckets[__bkt]->_M_nxt;
2125 143 : __new_buckets[__bkt]->_M_nxt = __p;
2126 : }
2127 1188 : __p = __next;
2128 : }
2129 :
2130 1809 : _M_deallocate_buckets();
2131 1809 : _M_bucket_count = __n;
2132 1809 : _M_buckets = __new_buckets;
2133 1809 : }
2134 :
2135 : // Rehash when there can be equivalent elements, preserve their relative
2136 : // order.
2137 : template<typename _Key, typename _Value,
2138 : typename _Alloc, typename _ExtractKey, typename _Equal,
2139 : typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
2140 : typename _Traits>
2141 : void
2142 : _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal,
2143 : _H1, _H2, _Hash, _RehashPolicy, _Traits>::
2144 : _M_rehash_aux(size_type __n, std::false_type)
2145 : {
2146 : __bucket_type* __new_buckets = _M_allocate_buckets(__n);
2147 :
2148 : __node_type* __p = _M_begin();
2149 : _M_before_begin._M_nxt = nullptr;
2150 : std::size_t __bbegin_bkt = 0;
2151 : std::size_t __prev_bkt = 0;
2152 : __node_type* __prev_p = nullptr;
2153 : bool __check_bucket = false;
2154 :
2155 : while (__p)
2156 : {
2157 : __node_type* __next = __p->_M_next();
2158 : std::size_t __bkt = __hash_code_base::_M_bucket_index(__p, __n);
2159 :
2160 : if (__prev_p && __prev_bkt == __bkt)
2161 : {
2162 : // Previous insert was already in this bucket, we insert after
2163 : // the previously inserted one to preserve equivalent elements
2164 : // relative order.
2165 : __p->_M_nxt = __prev_p->_M_nxt;
2166 : __prev_p->_M_nxt = __p;
2167 :
2168 : // Inserting after a node in a bucket require to check that we
2169 : // haven't change the bucket last node, in this case next
2170 : // bucket containing its before begin node must be updated. We
2171 : // schedule a check as soon as we move out of the sequence of
2172 : // equivalent nodes to limit the number of checks.
2173 : __check_bucket = true;
2174 : }
2175 : else
2176 : {
2177 : if (__check_bucket)
2178 : {
2179 : // Check if we shall update the next bucket because of
2180 : // insertions into __prev_bkt bucket.
2181 : if (__prev_p->_M_nxt)
2182 : {
2183 : std::size_t __next_bkt
2184 : = __hash_code_base::_M_bucket_index(__prev_p->_M_next(),
2185 : __n);
2186 : if (__next_bkt != __prev_bkt)
2187 : __new_buckets[__next_bkt] = __prev_p;
2188 : }
2189 : __check_bucket = false;
2190 : }
2191 :
2192 : if (!__new_buckets[__bkt])
2193 : {
2194 : __p->_M_nxt = _M_before_begin._M_nxt;
2195 : _M_before_begin._M_nxt = __p;
2196 : __new_buckets[__bkt] = &_M_before_begin;
2197 : if (__p->_M_nxt)
2198 : __new_buckets[__bbegin_bkt] = __p;
2199 : __bbegin_bkt = __bkt;
2200 : }
2201 : else
2202 : {
2203 : __p->_M_nxt = __new_buckets[__bkt]->_M_nxt;
2204 : __new_buckets[__bkt]->_M_nxt = __p;
2205 : }
2206 : }
2207 : __prev_p = __p;
2208 : __prev_bkt = __bkt;
2209 : __p = __next;
2210 : }
2211 :
2212 : if (__check_bucket && __prev_p->_M_nxt)
2213 : {
2214 : std::size_t __next_bkt
2215 : = __hash_code_base::_M_bucket_index(__prev_p->_M_next(), __n);
2216 : if (__next_bkt != __prev_bkt)
2217 : __new_buckets[__next_bkt] = __prev_p;
2218 : }
2219 :
2220 : _M_deallocate_buckets();
2221 : _M_bucket_count = __n;
2222 : _M_buckets = __new_buckets;
2223 : }
2224 :
2225 : #if __cplusplus > 201402L
2226 : template<typename, typename, typename> class _Hash_merge_helper { };
2227 : #endif // C++17
2228 :
2229 : _GLIBCXX_END_NAMESPACE_VERSION
2230 : } // namespace std
2231 :
2232 : #endif // _HASHTABLE_H
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