xref: /dflybsd-src/contrib/gcc-4.7/libstdc++-v3/include/bits/hashtable_policy.h (revision e4b17023d31ea40e02fa06b141db27753ecc6934)
1*e4b17023SJohn Marino // Internal policy header for unordered_set and unordered_map -*- C++ -*-
2*e4b17023SJohn Marino 
3*e4b17023SJohn Marino // Copyright (C) 2010, 2011, 2012 Free Software Foundation, Inc.
4*e4b17023SJohn Marino //
5*e4b17023SJohn Marino // This file is part of the GNU ISO C++ Library.  This library is free
6*e4b17023SJohn Marino // software; you can redistribute it and/or modify it under the
7*e4b17023SJohn Marino // terms of the GNU General Public License as published by the
8*e4b17023SJohn Marino // Free Software Foundation; either version 3, or (at your option)
9*e4b17023SJohn Marino // any later version.
10*e4b17023SJohn Marino 
11*e4b17023SJohn Marino // This library is distributed in the hope that it will be useful,
12*e4b17023SJohn Marino // but WITHOUT ANY WARRANTY; without even the implied warranty of
13*e4b17023SJohn Marino // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14*e4b17023SJohn Marino // GNU General Public License for more details.
15*e4b17023SJohn Marino 
16*e4b17023SJohn Marino // Under Section 7 of GPL version 3, you are granted additional
17*e4b17023SJohn Marino // permissions described in the GCC Runtime Library Exception, version
18*e4b17023SJohn Marino // 3.1, as published by the Free Software Foundation.
19*e4b17023SJohn Marino 
20*e4b17023SJohn Marino // You should have received a copy of the GNU General Public License and
21*e4b17023SJohn Marino // a copy of the GCC Runtime Library Exception along with this program;
22*e4b17023SJohn Marino // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
23*e4b17023SJohn Marino // <http://www.gnu.org/licenses/>.
24*e4b17023SJohn Marino 
25*e4b17023SJohn Marino /** @file bits/hashtable_policy.h
26*e4b17023SJohn Marino  *  This is an internal header file, included by other library headers.
27*e4b17023SJohn Marino  *  Do not attempt to use it directly.
28*e4b17023SJohn Marino  *  @headername{unordered_map,unordered_set}
29*e4b17023SJohn Marino  */
30*e4b17023SJohn Marino 
31*e4b17023SJohn Marino #ifndef _HASHTABLE_POLICY_H
32*e4b17023SJohn Marino #define _HASHTABLE_POLICY_H 1
33*e4b17023SJohn Marino 
34*e4b17023SJohn Marino namespace std _GLIBCXX_VISIBILITY(default)
35*e4b17023SJohn Marino {
36*e4b17023SJohn Marino namespace __detail
37*e4b17023SJohn Marino {
38*e4b17023SJohn Marino _GLIBCXX_BEGIN_NAMESPACE_VERSION
39*e4b17023SJohn Marino 
40*e4b17023SJohn Marino   // Helper function: return distance(first, last) for forward
41*e4b17023SJohn Marino   // iterators, or 0 for input iterators.
42*e4b17023SJohn Marino   template<class _Iterator>
43*e4b17023SJohn Marino     inline typename std::iterator_traits<_Iterator>::difference_type
44*e4b17023SJohn Marino     __distance_fw(_Iterator __first, _Iterator __last,
45*e4b17023SJohn Marino 		  std::input_iterator_tag)
46*e4b17023SJohn Marino     { return 0; }
47*e4b17023SJohn Marino 
48*e4b17023SJohn Marino   template<class _Iterator>
49*e4b17023SJohn Marino     inline typename std::iterator_traits<_Iterator>::difference_type
50*e4b17023SJohn Marino     __distance_fw(_Iterator __first, _Iterator __last,
51*e4b17023SJohn Marino 		  std::forward_iterator_tag)
52*e4b17023SJohn Marino     { return std::distance(__first, __last); }
53*e4b17023SJohn Marino 
54*e4b17023SJohn Marino   template<class _Iterator>
55*e4b17023SJohn Marino     inline typename std::iterator_traits<_Iterator>::difference_type
56*e4b17023SJohn Marino     __distance_fw(_Iterator __first, _Iterator __last)
57*e4b17023SJohn Marino     {
58*e4b17023SJohn Marino       typedef typename std::iterator_traits<_Iterator>::iterator_category _Tag;
59*e4b17023SJohn Marino       return __distance_fw(__first, __last, _Tag());
60*e4b17023SJohn Marino     }
61*e4b17023SJohn Marino 
62*e4b17023SJohn Marino   // Helper type used to detect when the hash functor is noexcept qualified or
63*e4b17023SJohn Marino   // not
64*e4b17023SJohn Marino   template <typename _Key, typename _Hash>
65*e4b17023SJohn Marino     struct __is_noexcept_hash : std::integral_constant<bool,
66*e4b17023SJohn Marino 	noexcept(declval<const _Hash&>()(declval<const _Key&>()))>
67*e4b17023SJohn Marino     {};
68*e4b17023SJohn Marino 
69*e4b17023SJohn Marino   // Auxiliary types used for all instantiations of _Hashtable: nodes
70*e4b17023SJohn Marino   // and iterators.
71*e4b17023SJohn Marino 
72*e4b17023SJohn Marino   // Nodes, used to wrap elements stored in the hash table.  A policy
73*e4b17023SJohn Marino   // template parameter of class template _Hashtable controls whether
74*e4b17023SJohn Marino   // nodes also store a hash code. In some cases (e.g. strings) this
75*e4b17023SJohn Marino   // may be a performance win.
76*e4b17023SJohn Marino   struct _Hash_node_base
77*e4b17023SJohn Marino   {
78*e4b17023SJohn Marino     _Hash_node_base* _M_nxt;
79*e4b17023SJohn Marino 
80*e4b17023SJohn Marino     _Hash_node_base()
81*e4b17023SJohn Marino       : _M_nxt() { }
82*e4b17023SJohn Marino     _Hash_node_base(_Hash_node_base* __next)
83*e4b17023SJohn Marino       : _M_nxt(__next) { }
84*e4b17023SJohn Marino   };
85*e4b17023SJohn Marino 
86*e4b17023SJohn Marino   template<typename _Value, bool __cache_hash_code>
87*e4b17023SJohn Marino     struct _Hash_node;
88*e4b17023SJohn Marino 
89*e4b17023SJohn Marino   template<typename _Value>
90*e4b17023SJohn Marino     struct _Hash_node<_Value, true> : _Hash_node_base
91*e4b17023SJohn Marino     {
92*e4b17023SJohn Marino       _Value       _M_v;
93*e4b17023SJohn Marino       std::size_t  _M_hash_code;
94*e4b17023SJohn Marino 
95*e4b17023SJohn Marino       template<typename... _Args>
96*e4b17023SJohn Marino 	_Hash_node(_Args&&... __args)
97*e4b17023SJohn Marino 	: _M_v(std::forward<_Args>(__args)...), _M_hash_code() { }
98*e4b17023SJohn Marino 
99*e4b17023SJohn Marino       _Hash_node* _M_next() const
100*e4b17023SJohn Marino       { return static_cast<_Hash_node*>(_M_nxt); }
101*e4b17023SJohn Marino     };
102*e4b17023SJohn Marino 
103*e4b17023SJohn Marino   template<typename _Value>
104*e4b17023SJohn Marino     struct _Hash_node<_Value, false> : _Hash_node_base
105*e4b17023SJohn Marino     {
106*e4b17023SJohn Marino       _Value       _M_v;
107*e4b17023SJohn Marino 
108*e4b17023SJohn Marino       template<typename... _Args>
109*e4b17023SJohn Marino 	_Hash_node(_Args&&... __args)
110*e4b17023SJohn Marino 	: _M_v(std::forward<_Args>(__args)...) { }
111*e4b17023SJohn Marino 
112*e4b17023SJohn Marino       _Hash_node* _M_next() const
113*e4b17023SJohn Marino       { return static_cast<_Hash_node*>(_M_nxt); }
114*e4b17023SJohn Marino     };
115*e4b17023SJohn Marino 
116*e4b17023SJohn Marino   // Node iterators, used to iterate through all the hashtable.
117*e4b17023SJohn Marino   template<typename _Value, bool __cache>
118*e4b17023SJohn Marino     struct _Node_iterator_base
119*e4b17023SJohn Marino     {
120*e4b17023SJohn Marino       _Node_iterator_base(_Hash_node<_Value, __cache>* __p)
121*e4b17023SJohn Marino       : _M_cur(__p) { }
122*e4b17023SJohn Marino 
123*e4b17023SJohn Marino       void
124*e4b17023SJohn Marino       _M_incr()
125*e4b17023SJohn Marino       { _M_cur = _M_cur->_M_next(); }
126*e4b17023SJohn Marino 
127*e4b17023SJohn Marino       _Hash_node<_Value, __cache>*  _M_cur;
128*e4b17023SJohn Marino     };
129*e4b17023SJohn Marino 
130*e4b17023SJohn Marino   template<typename _Value, bool __cache>
131*e4b17023SJohn Marino     inline bool
132*e4b17023SJohn Marino     operator==(const _Node_iterator_base<_Value, __cache>& __x,
133*e4b17023SJohn Marino 	       const _Node_iterator_base<_Value, __cache>& __y)
134*e4b17023SJohn Marino     { return __x._M_cur == __y._M_cur; }
135*e4b17023SJohn Marino 
136*e4b17023SJohn Marino   template<typename _Value, bool __cache>
137*e4b17023SJohn Marino     inline bool
138*e4b17023SJohn Marino     operator!=(const _Node_iterator_base<_Value, __cache>& __x,
139*e4b17023SJohn Marino 	       const _Node_iterator_base<_Value, __cache>& __y)
140*e4b17023SJohn Marino     { return __x._M_cur != __y._M_cur; }
141*e4b17023SJohn Marino 
142*e4b17023SJohn Marino   template<typename _Value, bool __constant_iterators, bool __cache>
143*e4b17023SJohn Marino     struct _Node_iterator
144*e4b17023SJohn Marino     : public _Node_iterator_base<_Value, __cache>
145*e4b17023SJohn Marino     {
146*e4b17023SJohn Marino       typedef _Value                                   value_type;
147*e4b17023SJohn Marino       typedef typename std::conditional<__constant_iterators,
148*e4b17023SJohn Marino 					const _Value*, _Value*>::type
149*e4b17023SJohn Marino 						       pointer;
150*e4b17023SJohn Marino       typedef typename std::conditional<__constant_iterators,
151*e4b17023SJohn Marino 					const _Value&, _Value&>::type
152*e4b17023SJohn Marino 						       reference;
153*e4b17023SJohn Marino       typedef std::ptrdiff_t                           difference_type;
154*e4b17023SJohn Marino       typedef std::forward_iterator_tag                iterator_category;
155*e4b17023SJohn Marino 
156*e4b17023SJohn Marino       _Node_iterator()
157*e4b17023SJohn Marino       : _Node_iterator_base<_Value, __cache>(0) { }
158*e4b17023SJohn Marino 
159*e4b17023SJohn Marino       explicit
160*e4b17023SJohn Marino       _Node_iterator(_Hash_node<_Value, __cache>* __p)
161*e4b17023SJohn Marino       : _Node_iterator_base<_Value, __cache>(__p) { }
162*e4b17023SJohn Marino 
163*e4b17023SJohn Marino       reference
164*e4b17023SJohn Marino       operator*() const
165*e4b17023SJohn Marino       { return this->_M_cur->_M_v; }
166*e4b17023SJohn Marino 
167*e4b17023SJohn Marino       pointer
168*e4b17023SJohn Marino       operator->() const
169*e4b17023SJohn Marino       { return std::__addressof(this->_M_cur->_M_v); }
170*e4b17023SJohn Marino 
171*e4b17023SJohn Marino       _Node_iterator&
172*e4b17023SJohn Marino       operator++()
173*e4b17023SJohn Marino       {
174*e4b17023SJohn Marino 	this->_M_incr();
175*e4b17023SJohn Marino 	return *this;
176*e4b17023SJohn Marino       }
177*e4b17023SJohn Marino 
178*e4b17023SJohn Marino       _Node_iterator
179*e4b17023SJohn Marino       operator++(int)
180*e4b17023SJohn Marino       {
181*e4b17023SJohn Marino 	_Node_iterator __tmp(*this);
182*e4b17023SJohn Marino 	this->_M_incr();
183*e4b17023SJohn Marino 	return __tmp;
184*e4b17023SJohn Marino       }
185*e4b17023SJohn Marino     };
186*e4b17023SJohn Marino 
187*e4b17023SJohn Marino   template<typename _Value, bool __constant_iterators, bool __cache>
188*e4b17023SJohn Marino     struct _Node_const_iterator
189*e4b17023SJohn Marino     : public _Node_iterator_base<_Value, __cache>
190*e4b17023SJohn Marino     {
191*e4b17023SJohn Marino       typedef _Value                                   value_type;
192*e4b17023SJohn Marino       typedef const _Value*                            pointer;
193*e4b17023SJohn Marino       typedef const _Value&                            reference;
194*e4b17023SJohn Marino       typedef std::ptrdiff_t                           difference_type;
195*e4b17023SJohn Marino       typedef std::forward_iterator_tag                iterator_category;
196*e4b17023SJohn Marino 
197*e4b17023SJohn Marino       _Node_const_iterator()
198*e4b17023SJohn Marino       : _Node_iterator_base<_Value, __cache>(0) { }
199*e4b17023SJohn Marino 
200*e4b17023SJohn Marino       explicit
201*e4b17023SJohn Marino       _Node_const_iterator(_Hash_node<_Value, __cache>* __p)
202*e4b17023SJohn Marino       : _Node_iterator_base<_Value, __cache>(__p) { }
203*e4b17023SJohn Marino 
204*e4b17023SJohn Marino       _Node_const_iterator(const _Node_iterator<_Value, __constant_iterators,
205*e4b17023SJohn Marino 			   __cache>& __x)
206*e4b17023SJohn Marino       : _Node_iterator_base<_Value, __cache>(__x._M_cur) { }
207*e4b17023SJohn Marino 
208*e4b17023SJohn Marino       reference
209*e4b17023SJohn Marino       operator*() const
210*e4b17023SJohn Marino       { return this->_M_cur->_M_v; }
211*e4b17023SJohn Marino 
212*e4b17023SJohn Marino       pointer
213*e4b17023SJohn Marino       operator->() const
214*e4b17023SJohn Marino       { return std::__addressof(this->_M_cur->_M_v); }
215*e4b17023SJohn Marino 
216*e4b17023SJohn Marino       _Node_const_iterator&
217*e4b17023SJohn Marino       operator++()
218*e4b17023SJohn Marino       {
219*e4b17023SJohn Marino 	this->_M_incr();
220*e4b17023SJohn Marino 	return *this;
221*e4b17023SJohn Marino       }
222*e4b17023SJohn Marino 
223*e4b17023SJohn Marino       _Node_const_iterator
224*e4b17023SJohn Marino       operator++(int)
225*e4b17023SJohn Marino       {
226*e4b17023SJohn Marino 	_Node_const_iterator __tmp(*this);
227*e4b17023SJohn Marino 	this->_M_incr();
228*e4b17023SJohn Marino 	return __tmp;
229*e4b17023SJohn Marino       }
230*e4b17023SJohn Marino     };
231*e4b17023SJohn Marino 
232*e4b17023SJohn Marino   // Many of class template _Hashtable's template parameters are policy
233*e4b17023SJohn Marino   // classes.  These are defaults for the policies.
234*e4b17023SJohn Marino 
235*e4b17023SJohn Marino   // Default range hashing function: use division to fold a large number
236*e4b17023SJohn Marino   // into the range [0, N).
237*e4b17023SJohn Marino   struct _Mod_range_hashing
238*e4b17023SJohn Marino   {
239*e4b17023SJohn Marino     typedef std::size_t first_argument_type;
240*e4b17023SJohn Marino     typedef std::size_t second_argument_type;
241*e4b17023SJohn Marino     typedef std::size_t result_type;
242*e4b17023SJohn Marino 
243*e4b17023SJohn Marino     result_type
244*e4b17023SJohn Marino     operator()(first_argument_type __num, second_argument_type __den) const
245*e4b17023SJohn Marino     { return __num % __den; }
246*e4b17023SJohn Marino   };
247*e4b17023SJohn Marino 
248*e4b17023SJohn Marino   // Default ranged hash function H.  In principle it should be a
249*e4b17023SJohn Marino   // function object composed from objects of type H1 and H2 such that
250*e4b17023SJohn Marino   // h(k, N) = h2(h1(k), N), but that would mean making extra copies of
251*e4b17023SJohn Marino   // h1 and h2.  So instead we'll just use a tag to tell class template
252*e4b17023SJohn Marino   // hashtable to do that composition.
253*e4b17023SJohn Marino   struct _Default_ranged_hash { };
254*e4b17023SJohn Marino 
255*e4b17023SJohn Marino   // Default value for rehash policy.  Bucket size is (usually) the
256*e4b17023SJohn Marino   // smallest prime that keeps the load factor small enough.
257*e4b17023SJohn Marino   struct _Prime_rehash_policy
258*e4b17023SJohn Marino   {
259*e4b17023SJohn Marino     _Prime_rehash_policy(float __z = 1.0)
260*e4b17023SJohn Marino     : _M_max_load_factor(__z), _M_prev_resize(0), _M_next_resize(0) { }
261*e4b17023SJohn Marino 
262*e4b17023SJohn Marino     float
263*e4b17023SJohn Marino     max_load_factor() const noexcept
264*e4b17023SJohn Marino     { return _M_max_load_factor; }
265*e4b17023SJohn Marino 
266*e4b17023SJohn Marino     // Return a bucket size no smaller than n.
267*e4b17023SJohn Marino     std::size_t
268*e4b17023SJohn Marino     _M_next_bkt(std::size_t __n) const;
269*e4b17023SJohn Marino 
270*e4b17023SJohn Marino     // Return a bucket count appropriate for n elements
271*e4b17023SJohn Marino     std::size_t
272*e4b17023SJohn Marino     _M_bkt_for_elements(std::size_t __n) const;
273*e4b17023SJohn Marino 
274*e4b17023SJohn Marino     // __n_bkt is current bucket count, __n_elt is current element count,
275*e4b17023SJohn Marino     // and __n_ins is number of elements to be inserted.  Do we need to
276*e4b17023SJohn Marino     // increase bucket count?  If so, return make_pair(true, n), where n
277*e4b17023SJohn Marino     // is the new bucket count.  If not, return make_pair(false, 0).
278*e4b17023SJohn Marino     std::pair<bool, std::size_t>
279*e4b17023SJohn Marino     _M_need_rehash(std::size_t __n_bkt, std::size_t __n_elt,
280*e4b17023SJohn Marino 		   std::size_t __n_ins) const;
281*e4b17023SJohn Marino 
282*e4b17023SJohn Marino     typedef std::pair<std::size_t, std::size_t> _State;
283*e4b17023SJohn Marino 
284*e4b17023SJohn Marino     _State
285*e4b17023SJohn Marino     _M_state() const
286*e4b17023SJohn Marino     { return std::make_pair(_M_prev_resize, _M_next_resize); }
287*e4b17023SJohn Marino 
288*e4b17023SJohn Marino     void
289*e4b17023SJohn Marino     _M_reset(const _State& __state)
290*e4b17023SJohn Marino     {
291*e4b17023SJohn Marino       _M_prev_resize = __state.first;
292*e4b17023SJohn Marino       _M_next_resize = __state.second;
293*e4b17023SJohn Marino     }
294*e4b17023SJohn Marino 
295*e4b17023SJohn Marino     enum { _S_n_primes = sizeof(unsigned long) != 8 ? 256 : 256 + 48 };
296*e4b17023SJohn Marino 
297*e4b17023SJohn Marino     static const std::size_t _S_growth_factor = 2;
298*e4b17023SJohn Marino 
299*e4b17023SJohn Marino     float                _M_max_load_factor;
300*e4b17023SJohn Marino     mutable std::size_t  _M_prev_resize;
301*e4b17023SJohn Marino     mutable std::size_t  _M_next_resize;
302*e4b17023SJohn Marino   };
303*e4b17023SJohn Marino 
304*e4b17023SJohn Marino   extern const unsigned long __prime_list[];
305*e4b17023SJohn Marino 
306*e4b17023SJohn Marino   // XXX This is a hack.  There's no good reason for any of
307*e4b17023SJohn Marino   // _Prime_rehash_policy's member functions to be inline.
308*e4b17023SJohn Marino 
309*e4b17023SJohn Marino   // Return a prime no smaller than n.
310*e4b17023SJohn Marino   inline std::size_t
311*e4b17023SJohn Marino   _Prime_rehash_policy::
312*e4b17023SJohn Marino   _M_next_bkt(std::size_t __n) const
313*e4b17023SJohn Marino   {
314*e4b17023SJohn Marino     // Optimize lookups involving the first elements of __prime_list.
315*e4b17023SJohn Marino     // (useful to speed-up, eg, constructors)
316*e4b17023SJohn Marino     static const unsigned char __fast_bkt[12]
317*e4b17023SJohn Marino       = { 2, 2, 2, 3, 5, 5, 7, 7, 11, 11, 11, 11 };
318*e4b17023SJohn Marino 
319*e4b17023SJohn Marino     const std::size_t __grown_n = __n * _S_growth_factor;
320*e4b17023SJohn Marino     if (__grown_n <= 11)
321*e4b17023SJohn Marino       {
322*e4b17023SJohn Marino 	_M_prev_resize = 0;
323*e4b17023SJohn Marino 	_M_next_resize
324*e4b17023SJohn Marino 	  = __builtin_ceil(__fast_bkt[__grown_n]
325*e4b17023SJohn Marino 			   * (long double)_M_max_load_factor);
326*e4b17023SJohn Marino 	return __fast_bkt[__grown_n];
327*e4b17023SJohn Marino       }
328*e4b17023SJohn Marino 
329*e4b17023SJohn Marino     const unsigned long* __next_bkt
330*e4b17023SJohn Marino       = std::lower_bound(__prime_list + 5, __prime_list + _S_n_primes,
331*e4b17023SJohn Marino 			 __grown_n);
332*e4b17023SJohn Marino     const unsigned long* __prev_bkt
333*e4b17023SJohn Marino       = std::lower_bound(__prime_list + 1, __next_bkt, __n / _S_growth_factor);
334*e4b17023SJohn Marino 
335*e4b17023SJohn Marino     _M_prev_resize
336*e4b17023SJohn Marino       = __builtin_floor(*(__prev_bkt - 1) * (long double)_M_max_load_factor);
337*e4b17023SJohn Marino     _M_next_resize
338*e4b17023SJohn Marino       = __builtin_ceil(*__next_bkt * (long double)_M_max_load_factor);
339*e4b17023SJohn Marino     return *__next_bkt;
340*e4b17023SJohn Marino   }
341*e4b17023SJohn Marino 
342*e4b17023SJohn Marino   // Return the smallest prime p such that alpha p >= n, where alpha
343*e4b17023SJohn Marino   // is the load factor.
344*e4b17023SJohn Marino   inline std::size_t
345*e4b17023SJohn Marino   _Prime_rehash_policy::
346*e4b17023SJohn Marino   _M_bkt_for_elements(std::size_t __n) const
347*e4b17023SJohn Marino   { return _M_next_bkt(__builtin_ceil(__n / (long double)_M_max_load_factor)); }
348*e4b17023SJohn Marino 
349*e4b17023SJohn Marino   // Finds the smallest prime p such that alpha p > __n_elt + __n_ins.
350*e4b17023SJohn Marino   // If p > __n_bkt, return make_pair(true, p); otherwise return
351*e4b17023SJohn Marino   // make_pair(false, 0).  In principle this isn't very different from
352*e4b17023SJohn Marino   // _M_bkt_for_elements.
353*e4b17023SJohn Marino 
354*e4b17023SJohn Marino   // The only tricky part is that we're caching the element count at
355*e4b17023SJohn Marino   // which we need to rehash, so we don't have to do a floating-point
356*e4b17023SJohn Marino   // multiply for every insertion.
357*e4b17023SJohn Marino 
358*e4b17023SJohn Marino   inline std::pair<bool, std::size_t>
359*e4b17023SJohn Marino   _Prime_rehash_policy::
360*e4b17023SJohn Marino   _M_need_rehash(std::size_t __n_bkt, std::size_t __n_elt,
361*e4b17023SJohn Marino 		 std::size_t __n_ins) const
362*e4b17023SJohn Marino   {
363*e4b17023SJohn Marino     if (__n_elt + __n_ins >= _M_next_resize)
364*e4b17023SJohn Marino       {
365*e4b17023SJohn Marino 	long double __min_bkts = (__n_elt + __n_ins)
366*e4b17023SJohn Marino 				 / (long double)_M_max_load_factor;
367*e4b17023SJohn Marino 	if (__min_bkts >= __n_bkt)
368*e4b17023SJohn Marino 	  return std::make_pair(true,
369*e4b17023SJohn Marino 				_M_next_bkt(__builtin_floor(__min_bkts) + 1));
370*e4b17023SJohn Marino 	else
371*e4b17023SJohn Marino 	  {
372*e4b17023SJohn Marino 	    _M_next_resize
373*e4b17023SJohn Marino 	      = __builtin_floor(__n_bkt * (long double)_M_max_load_factor);
374*e4b17023SJohn Marino 	    return std::make_pair(false, 0);
375*e4b17023SJohn Marino 	  }
376*e4b17023SJohn Marino       }
377*e4b17023SJohn Marino     else if (__n_elt + __n_ins < _M_prev_resize)
378*e4b17023SJohn Marino       {
379*e4b17023SJohn Marino 	long double __min_bkts = (__n_elt + __n_ins)
380*e4b17023SJohn Marino 				 / (long double)_M_max_load_factor;
381*e4b17023SJohn Marino 	return std::make_pair(true,
382*e4b17023SJohn Marino 			      _M_next_bkt(__builtin_floor(__min_bkts) + 1));
383*e4b17023SJohn Marino       }
384*e4b17023SJohn Marino     else
385*e4b17023SJohn Marino       return std::make_pair(false, 0);
386*e4b17023SJohn Marino   }
387*e4b17023SJohn Marino 
388*e4b17023SJohn Marino   // Base classes for std::_Hashtable.  We define these base classes
389*e4b17023SJohn Marino   // because in some cases we want to do different things depending
390*e4b17023SJohn Marino   // on the value of a policy class.  In some cases the policy class
391*e4b17023SJohn Marino   // affects which member functions and nested typedefs are defined;
392*e4b17023SJohn Marino   // we handle that by specializing base class templates.  Several of
393*e4b17023SJohn Marino   // the base class templates need to access other members of class
394*e4b17023SJohn Marino   // template _Hashtable, so we use the "curiously recurring template
395*e4b17023SJohn Marino   // pattern" for them.
396*e4b17023SJohn Marino 
397*e4b17023SJohn Marino   // class template _Map_base.  If the hashtable has a value type of
398*e4b17023SJohn Marino   // the form pair<T1, T2> and a key extraction policy that returns the
399*e4b17023SJohn Marino   // first part of the pair, the hashtable gets a mapped_type typedef.
400*e4b17023SJohn Marino   // If it satisfies those criteria and also has unique keys, then it
401*e4b17023SJohn Marino   // also gets an operator[].
402*e4b17023SJohn Marino   template<typename _Key, typename _Value, typename _Ex, bool __unique,
403*e4b17023SJohn Marino 	   typename _Hashtable>
404*e4b17023SJohn Marino     struct _Map_base { };
405*e4b17023SJohn Marino 
406*e4b17023SJohn Marino   template<typename _Key, typename _Pair, typename _Hashtable>
407*e4b17023SJohn Marino     struct _Map_base<_Key, _Pair, std::_Select1st<_Pair>, false, _Hashtable>
408*e4b17023SJohn Marino     {
409*e4b17023SJohn Marino       typedef typename _Pair::second_type mapped_type;
410*e4b17023SJohn Marino     };
411*e4b17023SJohn Marino 
412*e4b17023SJohn Marino   template<typename _Key, typename _Pair, typename _Hashtable>
413*e4b17023SJohn Marino     struct _Map_base<_Key, _Pair, std::_Select1st<_Pair>, true, _Hashtable>
414*e4b17023SJohn Marino     {
415*e4b17023SJohn Marino       typedef typename _Pair::second_type mapped_type;
416*e4b17023SJohn Marino 
417*e4b17023SJohn Marino       mapped_type&
418*e4b17023SJohn Marino       operator[](const _Key& __k);
419*e4b17023SJohn Marino 
420*e4b17023SJohn Marino       mapped_type&
421*e4b17023SJohn Marino       operator[](_Key&& __k);
422*e4b17023SJohn Marino 
423*e4b17023SJohn Marino       // _GLIBCXX_RESOLVE_LIB_DEFECTS
424*e4b17023SJohn Marino       // DR 761. unordered_map needs an at() member function.
425*e4b17023SJohn Marino       mapped_type&
426*e4b17023SJohn Marino       at(const _Key& __k);
427*e4b17023SJohn Marino 
428*e4b17023SJohn Marino       const mapped_type&
429*e4b17023SJohn Marino       at(const _Key& __k) const;
430*e4b17023SJohn Marino     };
431*e4b17023SJohn Marino 
432*e4b17023SJohn Marino   template<typename _Key, typename _Pair, typename _Hashtable>
433*e4b17023SJohn Marino     typename _Map_base<_Key, _Pair, std::_Select1st<_Pair>,
434*e4b17023SJohn Marino 		       true, _Hashtable>::mapped_type&
435*e4b17023SJohn Marino     _Map_base<_Key, _Pair, std::_Select1st<_Pair>, true, _Hashtable>::
436*e4b17023SJohn Marino     operator[](const _Key& __k)
437*e4b17023SJohn Marino     {
438*e4b17023SJohn Marino       _Hashtable* __h = static_cast<_Hashtable*>(this);
439*e4b17023SJohn Marino       typename _Hashtable::_Hash_code_type __code = __h->_M_hash_code(__k);
440*e4b17023SJohn Marino       std::size_t __n = __h->_M_bucket_index(__k, __code);
441*e4b17023SJohn Marino 
442*e4b17023SJohn Marino       typename _Hashtable::_Node* __p = __h->_M_find_node(__n, __k, __code);
443*e4b17023SJohn Marino       if (!__p)
444*e4b17023SJohn Marino 	return __h->_M_insert_bucket(std::make_pair(__k, mapped_type()),
445*e4b17023SJohn Marino 				     __n, __code)->second;
446*e4b17023SJohn Marino       return (__p->_M_v).second;
447*e4b17023SJohn Marino     }
448*e4b17023SJohn Marino 
449*e4b17023SJohn Marino   template<typename _Key, typename _Pair, typename _Hashtable>
450*e4b17023SJohn Marino     typename _Map_base<_Key, _Pair, std::_Select1st<_Pair>,
451*e4b17023SJohn Marino 		       true, _Hashtable>::mapped_type&
452*e4b17023SJohn Marino     _Map_base<_Key, _Pair, std::_Select1st<_Pair>, true, _Hashtable>::
453*e4b17023SJohn Marino     operator[](_Key&& __k)
454*e4b17023SJohn Marino     {
455*e4b17023SJohn Marino       _Hashtable* __h = static_cast<_Hashtable*>(this);
456*e4b17023SJohn Marino       typename _Hashtable::_Hash_code_type __code = __h->_M_hash_code(__k);
457*e4b17023SJohn Marino       std::size_t __n = __h->_M_bucket_index(__k, __code);
458*e4b17023SJohn Marino 
459*e4b17023SJohn Marino       typename _Hashtable::_Node* __p = __h->_M_find_node(__n, __k, __code);
460*e4b17023SJohn Marino       if (!__p)
461*e4b17023SJohn Marino 	return __h->_M_insert_bucket(std::make_pair(std::move(__k),
462*e4b17023SJohn Marino 						    mapped_type()),
463*e4b17023SJohn Marino 				     __n, __code)->second;
464*e4b17023SJohn Marino       return (__p->_M_v).second;
465*e4b17023SJohn Marino     }
466*e4b17023SJohn Marino 
467*e4b17023SJohn Marino   template<typename _Key, typename _Pair, typename _Hashtable>
468*e4b17023SJohn Marino     typename _Map_base<_Key, _Pair, std::_Select1st<_Pair>,
469*e4b17023SJohn Marino 		       true, _Hashtable>::mapped_type&
470*e4b17023SJohn Marino     _Map_base<_Key, _Pair, std::_Select1st<_Pair>, true, _Hashtable>::
471*e4b17023SJohn Marino     at(const _Key& __k)
472*e4b17023SJohn Marino     {
473*e4b17023SJohn Marino       _Hashtable* __h = static_cast<_Hashtable*>(this);
474*e4b17023SJohn Marino       typename _Hashtable::_Hash_code_type __code = __h->_M_hash_code(__k);
475*e4b17023SJohn Marino       std::size_t __n = __h->_M_bucket_index(__k, __code);
476*e4b17023SJohn Marino 
477*e4b17023SJohn Marino       typename _Hashtable::_Node* __p = __h->_M_find_node(__n, __k, __code);
478*e4b17023SJohn Marino       if (!__p)
479*e4b17023SJohn Marino 	__throw_out_of_range(__N("_Map_base::at"));
480*e4b17023SJohn Marino       return (__p->_M_v).second;
481*e4b17023SJohn Marino     }
482*e4b17023SJohn Marino 
483*e4b17023SJohn Marino   template<typename _Key, typename _Pair, typename _Hashtable>
484*e4b17023SJohn Marino     const typename _Map_base<_Key, _Pair, std::_Select1st<_Pair>,
485*e4b17023SJohn Marino 			     true, _Hashtable>::mapped_type&
486*e4b17023SJohn Marino     _Map_base<_Key, _Pair, std::_Select1st<_Pair>, true, _Hashtable>::
487*e4b17023SJohn Marino     at(const _Key& __k) const
488*e4b17023SJohn Marino     {
489*e4b17023SJohn Marino       const _Hashtable* __h = static_cast<const _Hashtable*>(this);
490*e4b17023SJohn Marino       typename _Hashtable::_Hash_code_type __code = __h->_M_hash_code(__k);
491*e4b17023SJohn Marino       std::size_t __n = __h->_M_bucket_index(__k, __code);
492*e4b17023SJohn Marino 
493*e4b17023SJohn Marino       typename _Hashtable::_Node* __p = __h->_M_find_node(__n, __k, __code);
494*e4b17023SJohn Marino       if (!__p)
495*e4b17023SJohn Marino 	__throw_out_of_range(__N("_Map_base::at"));
496*e4b17023SJohn Marino       return (__p->_M_v).second;
497*e4b17023SJohn Marino     }
498*e4b17023SJohn Marino 
499*e4b17023SJohn Marino   // class template _Rehash_base.  Give hashtable the max_load_factor
500*e4b17023SJohn Marino   // functions and reserve iff the rehash policy is _Prime_rehash_policy.
501*e4b17023SJohn Marino   template<typename _RehashPolicy, typename _Hashtable>
502*e4b17023SJohn Marino     struct _Rehash_base { };
503*e4b17023SJohn Marino 
504*e4b17023SJohn Marino   template<typename _Hashtable>
505*e4b17023SJohn Marino     struct _Rehash_base<_Prime_rehash_policy, _Hashtable>
506*e4b17023SJohn Marino     {
507*e4b17023SJohn Marino       float
508*e4b17023SJohn Marino       max_load_factor() const noexcept
509*e4b17023SJohn Marino       {
510*e4b17023SJohn Marino 	const _Hashtable* __this = static_cast<const _Hashtable*>(this);
511*e4b17023SJohn Marino 	return __this->__rehash_policy().max_load_factor();
512*e4b17023SJohn Marino       }
513*e4b17023SJohn Marino 
514*e4b17023SJohn Marino       void
515*e4b17023SJohn Marino       max_load_factor(float __z)
516*e4b17023SJohn Marino       {
517*e4b17023SJohn Marino 	_Hashtable* __this = static_cast<_Hashtable*>(this);
518*e4b17023SJohn Marino 	__this->__rehash_policy(_Prime_rehash_policy(__z));
519*e4b17023SJohn Marino       }
520*e4b17023SJohn Marino 
521*e4b17023SJohn Marino       void
522*e4b17023SJohn Marino       reserve(std::size_t __n)
523*e4b17023SJohn Marino       {
524*e4b17023SJohn Marino 	_Hashtable* __this = static_cast<_Hashtable*>(this);
525*e4b17023SJohn Marino 	__this->rehash(__builtin_ceil(__n / max_load_factor()));
526*e4b17023SJohn Marino       }
527*e4b17023SJohn Marino     };
528*e4b17023SJohn Marino 
529*e4b17023SJohn Marino   // Helper class using EBO when it is not forbidden, type is not final,
530*e4b17023SJohn Marino   // and when it worth it, type is empty.
531*e4b17023SJohn Marino   template<int _Nm, typename _Tp,
532*e4b17023SJohn Marino 	   bool __use_ebo = !__is_final(_Tp) && __is_empty(_Tp)>
533*e4b17023SJohn Marino     struct _Hashtable_ebo_helper;
534*e4b17023SJohn Marino 
535*e4b17023SJohn Marino   // Specialization using EBO.
536*e4b17023SJohn Marino   template<int _Nm, typename _Tp>
537*e4b17023SJohn Marino     struct _Hashtable_ebo_helper<_Nm, _Tp, true>
538*e4b17023SJohn Marino     // See PR53067.
539*e4b17023SJohn Marino     : public _Tp
540*e4b17023SJohn Marino     {
541*e4b17023SJohn Marino       _Hashtable_ebo_helper() = default;
542*e4b17023SJohn Marino       _Hashtable_ebo_helper(const _Tp& __tp) : _Tp(__tp)
543*e4b17023SJohn Marino       { }
544*e4b17023SJohn Marino 
545*e4b17023SJohn Marino       static const _Tp&
546*e4b17023SJohn Marino       _S_cget(const _Hashtable_ebo_helper& __eboh)
547*e4b17023SJohn Marino       { return static_cast<const _Tp&>(__eboh); }
548*e4b17023SJohn Marino 
549*e4b17023SJohn Marino       static _Tp&
550*e4b17023SJohn Marino       _S_get(_Hashtable_ebo_helper& __eboh)
551*e4b17023SJohn Marino       { return static_cast<_Tp&>(__eboh); }
552*e4b17023SJohn Marino     };
553*e4b17023SJohn Marino 
554*e4b17023SJohn Marino   // Specialization not using EBO.
555*e4b17023SJohn Marino   template<int _Nm, typename _Tp>
556*e4b17023SJohn Marino     struct _Hashtable_ebo_helper<_Nm, _Tp, false>
557*e4b17023SJohn Marino     {
558*e4b17023SJohn Marino       _Hashtable_ebo_helper() = default;
559*e4b17023SJohn Marino       _Hashtable_ebo_helper(const _Tp& __tp) : _M_tp(__tp)
560*e4b17023SJohn Marino       { }
561*e4b17023SJohn Marino 
562*e4b17023SJohn Marino       static const _Tp&
563*e4b17023SJohn Marino       _S_cget(const _Hashtable_ebo_helper& __eboh)
564*e4b17023SJohn Marino       { return __eboh._M_tp; }
565*e4b17023SJohn Marino 
566*e4b17023SJohn Marino       static _Tp&
567*e4b17023SJohn Marino       _S_get(_Hashtable_ebo_helper& __eboh)
568*e4b17023SJohn Marino       { return __eboh._M_tp; }
569*e4b17023SJohn Marino 
570*e4b17023SJohn Marino     private:
571*e4b17023SJohn Marino       _Tp _M_tp;
572*e4b17023SJohn Marino     };
573*e4b17023SJohn Marino 
574*e4b17023SJohn Marino   // Class template _Hash_code_base.  Encapsulates two policy issues that
575*e4b17023SJohn Marino   // aren't quite orthogonal.
576*e4b17023SJohn Marino   //   (1) the difference between using a ranged hash function and using
577*e4b17023SJohn Marino   //       the combination of a hash function and a range-hashing function.
578*e4b17023SJohn Marino   //       In the former case we don't have such things as hash codes, so
579*e4b17023SJohn Marino   //       we have a dummy type as placeholder.
580*e4b17023SJohn Marino   //   (2) Whether or not we cache hash codes.  Caching hash codes is
581*e4b17023SJohn Marino   //       meaningless if we have a ranged hash function.
582*e4b17023SJohn Marino   // We also put the key extraction objects here, for convenience.
583*e4b17023SJohn Marino   //
584*e4b17023SJohn Marino   // Each specialization derives from one or more of the template parameters to
585*e4b17023SJohn Marino   // benefit from Ebo. This is important as this type is inherited in some cases
586*e4b17023SJohn Marino   // by the _Local_iterator_base type used to implement local_iterator and
587*e4b17023SJohn Marino   // const_local_iterator. As with any iterator type we prefer to make it as
588*e4b17023SJohn Marino   // small as possible.
589*e4b17023SJohn Marino 
590*e4b17023SJohn Marino   // Primary template: unused except as a hook for specializations.
591*e4b17023SJohn Marino   template<typename _Key, typename _Value, typename _ExtractKey,
592*e4b17023SJohn Marino 	   typename _H1, typename _H2, typename _Hash,
593*e4b17023SJohn Marino 	   bool __cache_hash_code>
594*e4b17023SJohn Marino     struct _Hash_code_base;
595*e4b17023SJohn Marino 
596*e4b17023SJohn Marino   // Specialization: ranged hash function, no caching hash codes.  H1
597*e4b17023SJohn Marino   // and H2 are provided but ignored.  We define a dummy hash code type.
598*e4b17023SJohn Marino   template<typename _Key, typename _Value, typename _ExtractKey,
599*e4b17023SJohn Marino 	   typename _H1, typename _H2, typename _Hash>
600*e4b17023SJohn Marino     struct _Hash_code_base<_Key, _Value, _ExtractKey, _H1, _H2, _Hash, false>
601*e4b17023SJohn Marino     // See PR53067.
602*e4b17023SJohn Marino     : public  _Hashtable_ebo_helper<0, _ExtractKey>,
603*e4b17023SJohn Marino       public  _Hashtable_ebo_helper<1, _Hash>
604*e4b17023SJohn Marino     {
605*e4b17023SJohn Marino     private:
606*e4b17023SJohn Marino       typedef _Hashtable_ebo_helper<0, _ExtractKey> _EboExtractKey;
607*e4b17023SJohn Marino       typedef _Hashtable_ebo_helper<1, _Hash> _EboHash;
608*e4b17023SJohn Marino 
609*e4b17023SJohn Marino     protected:
610*e4b17023SJohn Marino       // We need the default constructor for the local iterators.
611*e4b17023SJohn Marino       _Hash_code_base() = default;
612*e4b17023SJohn Marino       _Hash_code_base(const _ExtractKey& __ex,
613*e4b17023SJohn Marino 		      const _H1&, const _H2&, const _Hash& __h)
614*e4b17023SJohn Marino 	: _EboExtractKey(__ex), _EboHash(__h) { }
615*e4b17023SJohn Marino 
616*e4b17023SJohn Marino       typedef void* _Hash_code_type;
617*e4b17023SJohn Marino 
618*e4b17023SJohn Marino       _Hash_code_type
619*e4b17023SJohn Marino       _M_hash_code(const _Key& __key) const
620*e4b17023SJohn Marino       { return 0; }
621*e4b17023SJohn Marino 
622*e4b17023SJohn Marino       std::size_t
623*e4b17023SJohn Marino       _M_bucket_index(const _Key& __k, _Hash_code_type,
624*e4b17023SJohn Marino 		      std::size_t __n) const
625*e4b17023SJohn Marino       { return _M_ranged_hash()(__k, __n); }
626*e4b17023SJohn Marino 
627*e4b17023SJohn Marino       std::size_t
628*e4b17023SJohn Marino       _M_bucket_index(const _Hash_node<_Value, false>* __p,
629*e4b17023SJohn Marino 		      std::size_t __n) const
630*e4b17023SJohn Marino       { return _M_ranged_hash()(_M_extract()(__p->_M_v), __n); }
631*e4b17023SJohn Marino 
632*e4b17023SJohn Marino       void
633*e4b17023SJohn Marino       _M_store_code(_Hash_node<_Value, false>*, _Hash_code_type) const
634*e4b17023SJohn Marino       { }
635*e4b17023SJohn Marino 
636*e4b17023SJohn Marino       void
637*e4b17023SJohn Marino       _M_copy_code(_Hash_node<_Value, false>*,
638*e4b17023SJohn Marino 		   const _Hash_node<_Value, false>*) const
639*e4b17023SJohn Marino       { }
640*e4b17023SJohn Marino 
641*e4b17023SJohn Marino       void
642*e4b17023SJohn Marino       _M_swap(_Hash_code_base& __x)
643*e4b17023SJohn Marino       {
644*e4b17023SJohn Marino 	std::swap(_M_extract(), __x._M_extract());
645*e4b17023SJohn Marino 	std::swap(_M_ranged_hash(), __x._M_ranged_hash());
646*e4b17023SJohn Marino       }
647*e4b17023SJohn Marino 
648*e4b17023SJohn Marino     protected:
649*e4b17023SJohn Marino       const _ExtractKey&
650*e4b17023SJohn Marino       _M_extract() const { return _EboExtractKey::_S_cget(*this); }
651*e4b17023SJohn Marino       _ExtractKey&
652*e4b17023SJohn Marino       _M_extract() { return _EboExtractKey::_S_get(*this); }
653*e4b17023SJohn Marino       const _Hash&
654*e4b17023SJohn Marino       _M_ranged_hash() const { return _EboHash::_S_cget(*this); }
655*e4b17023SJohn Marino       _Hash&
656*e4b17023SJohn Marino       _M_ranged_hash() { return _EboHash::_S_get(*this); }
657*e4b17023SJohn Marino     };
658*e4b17023SJohn Marino 
659*e4b17023SJohn Marino   // No specialization for ranged hash function while caching hash codes.
660*e4b17023SJohn Marino   // That combination is meaningless, and trying to do it is an error.
661*e4b17023SJohn Marino 
662*e4b17023SJohn Marino   // Specialization: ranged hash function, cache hash codes.  This
663*e4b17023SJohn Marino   // combination is meaningless, so we provide only a declaration
664*e4b17023SJohn Marino   // and no definition.
665*e4b17023SJohn Marino   template<typename _Key, typename _Value, typename _ExtractKey,
666*e4b17023SJohn Marino 	   typename _H1, typename _H2, typename _Hash>
667*e4b17023SJohn Marino     struct _Hash_code_base<_Key, _Value, _ExtractKey, _H1, _H2, _Hash, true>;
668*e4b17023SJohn Marino 
669*e4b17023SJohn Marino   // Specialization: hash function and range-hashing function, no
670*e4b17023SJohn Marino   // caching of hash codes.
671*e4b17023SJohn Marino   // Provides typedef and accessor required by TR1.
672*e4b17023SJohn Marino   template<typename _Key, typename _Value, typename _ExtractKey,
673*e4b17023SJohn Marino 	   typename _H1, typename _H2>
674*e4b17023SJohn Marino     struct _Hash_code_base<_Key, _Value, _ExtractKey, _H1, _H2,
675*e4b17023SJohn Marino 			   _Default_ranged_hash, false>
676*e4b17023SJohn Marino     // See PR53067.
677*e4b17023SJohn Marino     : public  _Hashtable_ebo_helper<0, _ExtractKey>,
678*e4b17023SJohn Marino       public  _Hashtable_ebo_helper<1, _H1>,
679*e4b17023SJohn Marino       public  _Hashtable_ebo_helper<2, _H2>
680*e4b17023SJohn Marino     {
681*e4b17023SJohn Marino     private:
682*e4b17023SJohn Marino       typedef _Hashtable_ebo_helper<0, _ExtractKey> _EboExtractKey;
683*e4b17023SJohn Marino       typedef _Hashtable_ebo_helper<1, _H1> _EboH1;
684*e4b17023SJohn Marino       typedef _Hashtable_ebo_helper<2, _H2> _EboH2;
685*e4b17023SJohn Marino 
686*e4b17023SJohn Marino     public:
687*e4b17023SJohn Marino       typedef _H1 hasher;
688*e4b17023SJohn Marino 
689*e4b17023SJohn Marino       hasher
690*e4b17023SJohn Marino       hash_function() const
691*e4b17023SJohn Marino       { return _M_h1(); }
692*e4b17023SJohn Marino 
693*e4b17023SJohn Marino     protected:
694*e4b17023SJohn Marino       // We need the default constructor for the local iterators.
695*e4b17023SJohn Marino       _Hash_code_base() = default;
696*e4b17023SJohn Marino       _Hash_code_base(const _ExtractKey& __ex,
697*e4b17023SJohn Marino 		      const _H1& __h1, const _H2& __h2,
698*e4b17023SJohn Marino 		      const _Default_ranged_hash&)
699*e4b17023SJohn Marino       : _EboExtractKey(__ex), _EboH1(__h1), _EboH2(__h2) { }
700*e4b17023SJohn Marino 
701*e4b17023SJohn Marino       typedef std::size_t _Hash_code_type;
702*e4b17023SJohn Marino 
703*e4b17023SJohn Marino       _Hash_code_type
704*e4b17023SJohn Marino       _M_hash_code(const _Key& __k) const
705*e4b17023SJohn Marino       { return _M_h1()(__k); }
706*e4b17023SJohn Marino 
707*e4b17023SJohn Marino       std::size_t
708*e4b17023SJohn Marino       _M_bucket_index(const _Key&, _Hash_code_type __c,
709*e4b17023SJohn Marino 		      std::size_t __n) const
710*e4b17023SJohn Marino       { return _M_h2()(__c, __n); }
711*e4b17023SJohn Marino 
712*e4b17023SJohn Marino       std::size_t
713*e4b17023SJohn Marino       _M_bucket_index(const _Hash_node<_Value, false>* __p,
714*e4b17023SJohn Marino 		      std::size_t __n) const
715*e4b17023SJohn Marino       { return _M_h2()(_M_h1()(_M_extract()(__p->_M_v)), __n); }
716*e4b17023SJohn Marino 
717*e4b17023SJohn Marino       void
718*e4b17023SJohn Marino       _M_store_code(_Hash_node<_Value, false>*, _Hash_code_type) const
719*e4b17023SJohn Marino       { }
720*e4b17023SJohn Marino 
721*e4b17023SJohn Marino       void
722*e4b17023SJohn Marino       _M_copy_code(_Hash_node<_Value, false>*,
723*e4b17023SJohn Marino 		   const _Hash_node<_Value, false>*) const
724*e4b17023SJohn Marino       { }
725*e4b17023SJohn Marino 
726*e4b17023SJohn Marino       void
727*e4b17023SJohn Marino       _M_swap(_Hash_code_base& __x)
728*e4b17023SJohn Marino       {
729*e4b17023SJohn Marino 	std::swap(_M_extract(), __x._M_extract());
730*e4b17023SJohn Marino 	std::swap(_M_h1(), __x._M_h1());
731*e4b17023SJohn Marino 	std::swap(_M_h2(), __x._M_h2());
732*e4b17023SJohn Marino       }
733*e4b17023SJohn Marino 
734*e4b17023SJohn Marino     protected:
735*e4b17023SJohn Marino       const _ExtractKey&
736*e4b17023SJohn Marino       _M_extract() const { return _EboExtractKey::_S_cget(*this); }
737*e4b17023SJohn Marino       _ExtractKey&
738*e4b17023SJohn Marino       _M_extract() { return _EboExtractKey::_S_get(*this); }
739*e4b17023SJohn Marino       const _H1&
740*e4b17023SJohn Marino       _M_h1() const { return _EboH1::_S_cget(*this); }
741*e4b17023SJohn Marino       _H1&
742*e4b17023SJohn Marino       _M_h1() { return _EboH1::_S_get(*this); }
743*e4b17023SJohn Marino       const _H2&
744*e4b17023SJohn Marino       _M_h2() const { return _EboH2::_S_cget(*this); }
745*e4b17023SJohn Marino       _H2&
746*e4b17023SJohn Marino       _M_h2() { return _EboH2::_S_get(*this); }
747*e4b17023SJohn Marino     };
748*e4b17023SJohn Marino 
749*e4b17023SJohn Marino   // Specialization: hash function and range-hashing function,
750*e4b17023SJohn Marino   // caching hash codes.  H is provided but ignored.  Provides
751*e4b17023SJohn Marino   // typedef and accessor required by TR1.
752*e4b17023SJohn Marino   template<typename _Key, typename _Value, typename _ExtractKey,
753*e4b17023SJohn Marino 	   typename _H1, typename _H2>
754*e4b17023SJohn Marino     struct _Hash_code_base<_Key, _Value, _ExtractKey, _H1, _H2,
755*e4b17023SJohn Marino 			   _Default_ranged_hash, true>
756*e4b17023SJohn Marino     // See PR53067.
757*e4b17023SJohn Marino     : public  _Hashtable_ebo_helper<0, _ExtractKey>,
758*e4b17023SJohn Marino       public  _Hashtable_ebo_helper<1, _H1>,
759*e4b17023SJohn Marino       public  _Hashtable_ebo_helper<2, _H2>
760*e4b17023SJohn Marino     {
761*e4b17023SJohn Marino     private:
762*e4b17023SJohn Marino       typedef _Hashtable_ebo_helper<0, _ExtractKey> _EboExtractKey;
763*e4b17023SJohn Marino       typedef _Hashtable_ebo_helper<1, _H1> _EboH1;
764*e4b17023SJohn Marino       typedef _Hashtable_ebo_helper<2, _H2> _EboH2;
765*e4b17023SJohn Marino 
766*e4b17023SJohn Marino     public:
767*e4b17023SJohn Marino       typedef _H1 hasher;
768*e4b17023SJohn Marino 
769*e4b17023SJohn Marino       hasher
770*e4b17023SJohn Marino       hash_function() const
771*e4b17023SJohn Marino       { return _M_h1(); }
772*e4b17023SJohn Marino 
773*e4b17023SJohn Marino     protected:
774*e4b17023SJohn Marino       _Hash_code_base(const _ExtractKey& __ex,
775*e4b17023SJohn Marino 		      const _H1& __h1, const _H2& __h2,
776*e4b17023SJohn Marino 		      const _Default_ranged_hash&)
777*e4b17023SJohn Marino       : _EboExtractKey(__ex), _EboH1(__h1), _EboH2(__h2) { }
778*e4b17023SJohn Marino 
779*e4b17023SJohn Marino       typedef std::size_t _Hash_code_type;
780*e4b17023SJohn Marino 
781*e4b17023SJohn Marino       _Hash_code_type
782*e4b17023SJohn Marino       _M_hash_code(const _Key& __k) const
783*e4b17023SJohn Marino       { return _M_h1()(__k); }
784*e4b17023SJohn Marino 
785*e4b17023SJohn Marino       std::size_t
786*e4b17023SJohn Marino       _M_bucket_index(const _Key&, _Hash_code_type __c,
787*e4b17023SJohn Marino 		      std::size_t __n) const
788*e4b17023SJohn Marino       { return _M_h2()(__c, __n); }
789*e4b17023SJohn Marino 
790*e4b17023SJohn Marino       std::size_t
791*e4b17023SJohn Marino       _M_bucket_index(const _Hash_node<_Value, true>* __p,
792*e4b17023SJohn Marino 		      std::size_t __n) const
793*e4b17023SJohn Marino       { return _M_h2()(__p->_M_hash_code, __n); }
794*e4b17023SJohn Marino 
795*e4b17023SJohn Marino       void
796*e4b17023SJohn Marino       _M_store_code(_Hash_node<_Value, true>* __n, _Hash_code_type __c) const
797*e4b17023SJohn Marino       { __n->_M_hash_code = __c; }
798*e4b17023SJohn Marino 
799*e4b17023SJohn Marino       void
800*e4b17023SJohn Marino       _M_copy_code(_Hash_node<_Value, true>* __to,
801*e4b17023SJohn Marino 		   const _Hash_node<_Value, true>* __from) const
802*e4b17023SJohn Marino       { __to->_M_hash_code = __from->_M_hash_code; }
803*e4b17023SJohn Marino 
804*e4b17023SJohn Marino       void
805*e4b17023SJohn Marino       _M_swap(_Hash_code_base& __x)
806*e4b17023SJohn Marino       {
807*e4b17023SJohn Marino 	std::swap(_M_extract(), __x._M_extract());
808*e4b17023SJohn Marino 	std::swap(_M_h1(), __x._M_h1());
809*e4b17023SJohn Marino 	std::swap(_M_h2(), __x._M_h2());
810*e4b17023SJohn Marino       }
811*e4b17023SJohn Marino 
812*e4b17023SJohn Marino     protected:
813*e4b17023SJohn Marino       const _ExtractKey&
814*e4b17023SJohn Marino       _M_extract() const { return _EboExtractKey::_S_cget(*this); }
815*e4b17023SJohn Marino       _ExtractKey&
816*e4b17023SJohn Marino       _M_extract() { return _EboExtractKey::_S_get(*this); }
817*e4b17023SJohn Marino       const _H1&
818*e4b17023SJohn Marino       _M_h1() const { return _EboH1::_S_cget(*this); }
819*e4b17023SJohn Marino       _H1&
820*e4b17023SJohn Marino       _M_h1() { return _EboH1::_S_get(*this); }
821*e4b17023SJohn Marino       const _H2&
822*e4b17023SJohn Marino       _M_h2() const { return _EboH2::_S_cget(*this); }
823*e4b17023SJohn Marino       _H2&
824*e4b17023SJohn Marino       _M_h2() { return _EboH2::_S_get(*this); }
825*e4b17023SJohn Marino     };
826*e4b17023SJohn Marino 
827*e4b17023SJohn Marino   template <typename _Key, typename _Value, typename _ExtractKey,
828*e4b17023SJohn Marino 	    typename _Equal, typename _HashCodeType,
829*e4b17023SJohn Marino 	    bool __cache_hash_code>
830*e4b17023SJohn Marino   struct _Equal_helper;
831*e4b17023SJohn Marino 
832*e4b17023SJohn Marino   template<typename _Key, typename _Value, typename _ExtractKey,
833*e4b17023SJohn Marino 	   typename _Equal, typename _HashCodeType>
834*e4b17023SJohn Marino   struct _Equal_helper<_Key, _Value, _ExtractKey, _Equal, _HashCodeType, true>
835*e4b17023SJohn Marino   {
836*e4b17023SJohn Marino     static bool
837*e4b17023SJohn Marino     _S_equals(const _Equal& __eq, const _ExtractKey& __extract,
838*e4b17023SJohn Marino 	      const _Key& __k, _HashCodeType __c,
839*e4b17023SJohn Marino 	      _Hash_node<_Value, true>* __n)
840*e4b17023SJohn Marino     { return __c == __n->_M_hash_code
841*e4b17023SJohn Marino 	     && __eq(__k, __extract(__n->_M_v)); }
842*e4b17023SJohn Marino   };
843*e4b17023SJohn Marino 
844*e4b17023SJohn Marino   template<typename _Key, typename _Value, typename _ExtractKey,
845*e4b17023SJohn Marino 	   typename _Equal, typename _HashCodeType>
846*e4b17023SJohn Marino   struct _Equal_helper<_Key, _Value, _ExtractKey, _Equal, _HashCodeType, false>
847*e4b17023SJohn Marino   {
848*e4b17023SJohn Marino     static bool
849*e4b17023SJohn Marino     _S_equals(const _Equal& __eq, const _ExtractKey& __extract,
850*e4b17023SJohn Marino 	      const _Key& __k, _HashCodeType,
851*e4b17023SJohn Marino 	      _Hash_node<_Value, false>* __n)
852*e4b17023SJohn Marino     { return __eq(__k, __extract(__n->_M_v)); }
853*e4b17023SJohn Marino   };
854*e4b17023SJohn Marino 
855*e4b17023SJohn Marino   // Helper class adding management of _Equal functor to _Hash_code_base
856*e4b17023SJohn Marino   // type.
857*e4b17023SJohn Marino   template<typename _Key, typename _Value,
858*e4b17023SJohn Marino 	   typename _ExtractKey, typename _Equal,
859*e4b17023SJohn Marino 	   typename _H1, typename _H2, typename _Hash,
860*e4b17023SJohn Marino 	   bool __cache_hash_code>
861*e4b17023SJohn Marino   struct _Hashtable_base
862*e4b17023SJohn Marino   // See PR53067.
863*e4b17023SJohn Marino   : public  _Hash_code_base<_Key, _Value, _ExtractKey, _H1, _H2, _Hash,
864*e4b17023SJohn Marino 			    __cache_hash_code>,
865*e4b17023SJohn Marino     public _Hashtable_ebo_helper<0, _Equal>
866*e4b17023SJohn Marino   {
867*e4b17023SJohn Marino   private:
868*e4b17023SJohn Marino     typedef _Hashtable_ebo_helper<0, _Equal> _EboEqual;
869*e4b17023SJohn Marino 
870*e4b17023SJohn Marino   protected:
871*e4b17023SJohn Marino     typedef _Hash_code_base<_Key, _Value, _ExtractKey,
872*e4b17023SJohn Marino 			    _H1, _H2, _Hash, __cache_hash_code> _HCBase;
873*e4b17023SJohn Marino     typedef typename _HCBase::_Hash_code_type _Hash_code_type;
874*e4b17023SJohn Marino 
875*e4b17023SJohn Marino     _Hashtable_base(const _ExtractKey& __ex,
876*e4b17023SJohn Marino 		    const _H1& __h1, const _H2& __h2,
877*e4b17023SJohn Marino 		    const _Hash& __hash, const _Equal& __eq)
878*e4b17023SJohn Marino       : _HCBase(__ex, __h1, __h2, __hash), _EboEqual(__eq) { }
879*e4b17023SJohn Marino 
880*e4b17023SJohn Marino     bool
881*e4b17023SJohn Marino     _M_equals(const _Key& __k, _Hash_code_type __c,
882*e4b17023SJohn Marino 	      _Hash_node<_Value, __cache_hash_code>* __n) const
883*e4b17023SJohn Marino     {
884*e4b17023SJohn Marino       typedef _Equal_helper<_Key, _Value, _ExtractKey,
885*e4b17023SJohn Marino 			   _Equal, _Hash_code_type,
886*e4b17023SJohn Marino 			   __cache_hash_code> _EqualHelper;
887*e4b17023SJohn Marino       return _EqualHelper::_S_equals(_M_eq(), this->_M_extract(),
888*e4b17023SJohn Marino 				     __k, __c, __n);
889*e4b17023SJohn Marino     }
890*e4b17023SJohn Marino 
891*e4b17023SJohn Marino     void
892*e4b17023SJohn Marino     _M_swap(_Hashtable_base& __x)
893*e4b17023SJohn Marino     {
894*e4b17023SJohn Marino       _HCBase::_M_swap(__x);
895*e4b17023SJohn Marino       std::swap(_M_eq(), __x._M_eq());
896*e4b17023SJohn Marino     }
897*e4b17023SJohn Marino 
898*e4b17023SJohn Marino   protected:
899*e4b17023SJohn Marino     const _Equal&
900*e4b17023SJohn Marino     _M_eq() const { return _EboEqual::_S_cget(*this); }
901*e4b17023SJohn Marino     _Equal&
902*e4b17023SJohn Marino     _M_eq() { return _EboEqual::_S_get(*this); }
903*e4b17023SJohn Marino   };
904*e4b17023SJohn Marino 
905*e4b17023SJohn Marino   // Local iterators, used to iterate within a bucket but not between
906*e4b17023SJohn Marino   // buckets.
907*e4b17023SJohn Marino   template<typename _Key, typename _Value, typename _ExtractKey,
908*e4b17023SJohn Marino 	   typename _H1, typename _H2, typename _Hash,
909*e4b17023SJohn Marino 	   bool __cache_hash_code>
910*e4b17023SJohn Marino     struct _Local_iterator_base;
911*e4b17023SJohn Marino 
912*e4b17023SJohn Marino   template<typename _Key, typename _Value, typename _ExtractKey,
913*e4b17023SJohn Marino 	   typename _H1, typename _H2, typename _Hash>
914*e4b17023SJohn Marino     struct _Local_iterator_base<_Key, _Value, _ExtractKey,
915*e4b17023SJohn Marino 				_H1, _H2, _Hash, true>
916*e4b17023SJohn Marino     // See PR53067.
917*e4b17023SJohn Marino     : public _H2
918*e4b17023SJohn Marino     {
919*e4b17023SJohn Marino       _Local_iterator_base() = default;
920*e4b17023SJohn Marino       _Local_iterator_base(_Hash_node<_Value, true>* __p,
921*e4b17023SJohn Marino 			   std::size_t __bkt, std::size_t __bkt_count)
922*e4b17023SJohn Marino       : _M_cur(__p), _M_bucket(__bkt), _M_bucket_count(__bkt_count) { }
923*e4b17023SJohn Marino 
924*e4b17023SJohn Marino       void
925*e4b17023SJohn Marino       _M_incr()
926*e4b17023SJohn Marino       {
927*e4b17023SJohn Marino 	_M_cur = _M_cur->_M_next();
928*e4b17023SJohn Marino 	if (_M_cur)
929*e4b17023SJohn Marino 	  {
930*e4b17023SJohn Marino 	    std::size_t __bkt = _M_h2()(_M_cur->_M_hash_code, _M_bucket_count);
931*e4b17023SJohn Marino 	    if (__bkt != _M_bucket)
932*e4b17023SJohn Marino 	      _M_cur = nullptr;
933*e4b17023SJohn Marino 	  }
934*e4b17023SJohn Marino       }
935*e4b17023SJohn Marino 
936*e4b17023SJohn Marino       const _H2& _M_h2() const
937*e4b17023SJohn Marino       { return *this; }
938*e4b17023SJohn Marino 
939*e4b17023SJohn Marino       _Hash_node<_Value, true>*  _M_cur;
940*e4b17023SJohn Marino       std::size_t _M_bucket;
941*e4b17023SJohn Marino       std::size_t _M_bucket_count;
942*e4b17023SJohn Marino     };
943*e4b17023SJohn Marino 
944*e4b17023SJohn Marino   template<typename _Key, typename _Value, typename _ExtractKey,
945*e4b17023SJohn Marino 	   typename _H1, typename _H2, typename _Hash>
946*e4b17023SJohn Marino     struct _Local_iterator_base<_Key, _Value, _ExtractKey,
947*e4b17023SJohn Marino 				_H1, _H2, _Hash, false>
948*e4b17023SJohn Marino     // See PR53067.
949*e4b17023SJohn Marino     : public _Hash_code_base<_Key, _Value, _ExtractKey,
950*e4b17023SJohn Marino 			     _H1, _H2, _Hash, false>
951*e4b17023SJohn Marino     {
952*e4b17023SJohn Marino       _Local_iterator_base() = default;
953*e4b17023SJohn Marino       _Local_iterator_base(_Hash_node<_Value, false>* __p,
954*e4b17023SJohn Marino 			   std::size_t __bkt, std::size_t __bkt_count)
955*e4b17023SJohn Marino       : _M_cur(__p), _M_bucket(__bkt), _M_bucket_count(__bkt_count) { }
956*e4b17023SJohn Marino 
957*e4b17023SJohn Marino       void
958*e4b17023SJohn Marino       _M_incr()
959*e4b17023SJohn Marino       {
960*e4b17023SJohn Marino 	_M_cur = _M_cur->_M_next();
961*e4b17023SJohn Marino 	if (_M_cur)
962*e4b17023SJohn Marino 	  {
963*e4b17023SJohn Marino 	    std::size_t __bkt = this->_M_bucket_index(_M_cur, _M_bucket_count);
964*e4b17023SJohn Marino 	    if (__bkt != _M_bucket)
965*e4b17023SJohn Marino 	      _M_cur = nullptr;
966*e4b17023SJohn Marino 	  }
967*e4b17023SJohn Marino       }
968*e4b17023SJohn Marino 
969*e4b17023SJohn Marino       _Hash_node<_Value, false>*  _M_cur;
970*e4b17023SJohn Marino       std::size_t _M_bucket;
971*e4b17023SJohn Marino       std::size_t _M_bucket_count;
972*e4b17023SJohn Marino     };
973*e4b17023SJohn Marino 
974*e4b17023SJohn Marino   template<typename _Key, typename _Value, typename _ExtractKey,
975*e4b17023SJohn Marino 	   typename _H1, typename _H2, typename _Hash, bool __cache>
976*e4b17023SJohn Marino     inline bool
977*e4b17023SJohn Marino     operator==(const _Local_iterator_base<_Key, _Value, _ExtractKey,
978*e4b17023SJohn Marino 					  _H1, _H2, _Hash, __cache>& __x,
979*e4b17023SJohn Marino 	       const _Local_iterator_base<_Key, _Value, _ExtractKey,
980*e4b17023SJohn Marino 					  _H1, _H2, _Hash, __cache>& __y)
981*e4b17023SJohn Marino     { return __x._M_cur == __y._M_cur; }
982*e4b17023SJohn Marino 
983*e4b17023SJohn Marino   template<typename _Key, typename _Value, typename _ExtractKey,
984*e4b17023SJohn Marino 	   typename _H1, typename _H2, typename _Hash, bool __cache>
985*e4b17023SJohn Marino     inline bool
986*e4b17023SJohn Marino     operator!=(const _Local_iterator_base<_Key, _Value, _ExtractKey,
987*e4b17023SJohn Marino 					  _H1, _H2, _Hash, __cache>& __x,
988*e4b17023SJohn Marino 	       const _Local_iterator_base<_Key, _Value, _ExtractKey,
989*e4b17023SJohn Marino 					  _H1, _H2, _Hash, __cache>& __y)
990*e4b17023SJohn Marino     { return __x._M_cur != __y._M_cur; }
991*e4b17023SJohn Marino 
992*e4b17023SJohn Marino   template<typename _Key, typename _Value, typename _ExtractKey,
993*e4b17023SJohn Marino 	   typename _H1, typename _H2, typename _Hash,
994*e4b17023SJohn Marino 	   bool __constant_iterators, bool __cache>
995*e4b17023SJohn Marino     struct _Local_iterator
996*e4b17023SJohn Marino     : public _Local_iterator_base<_Key, _Value, _ExtractKey,
997*e4b17023SJohn Marino 				  _H1, _H2, _Hash, __cache>
998*e4b17023SJohn Marino     {
999*e4b17023SJohn Marino       typedef _Value                                   value_type;
1000*e4b17023SJohn Marino       typedef typename std::conditional<__constant_iterators,
1001*e4b17023SJohn Marino 					const _Value*, _Value*>::type
1002*e4b17023SJohn Marino 						       pointer;
1003*e4b17023SJohn Marino       typedef typename std::conditional<__constant_iterators,
1004*e4b17023SJohn Marino 					const _Value&, _Value&>::type
1005*e4b17023SJohn Marino 						       reference;
1006*e4b17023SJohn Marino       typedef std::ptrdiff_t                           difference_type;
1007*e4b17023SJohn Marino       typedef std::forward_iterator_tag                iterator_category;
1008*e4b17023SJohn Marino 
1009*e4b17023SJohn Marino       _Local_iterator() = default;
1010*e4b17023SJohn Marino 
1011*e4b17023SJohn Marino       explicit
1012*e4b17023SJohn Marino       _Local_iterator(_Hash_node<_Value, __cache>* __p,
1013*e4b17023SJohn Marino 		      std::size_t __bkt, std::size_t __bkt_count)
1014*e4b17023SJohn Marino       : _Local_iterator_base<_Key, _Value, _ExtractKey, _H1, _H2, _Hash,
1015*e4b17023SJohn Marino 			     __cache>(__p, __bkt, __bkt_count)
1016*e4b17023SJohn Marino       { }
1017*e4b17023SJohn Marino 
1018*e4b17023SJohn Marino       reference
1019*e4b17023SJohn Marino       operator*() const
1020*e4b17023SJohn Marino       { return this->_M_cur->_M_v; }
1021*e4b17023SJohn Marino 
1022*e4b17023SJohn Marino       pointer
1023*e4b17023SJohn Marino       operator->() const
1024*e4b17023SJohn Marino       { return std::__addressof(this->_M_cur->_M_v); }
1025*e4b17023SJohn Marino 
1026*e4b17023SJohn Marino       _Local_iterator&
1027*e4b17023SJohn Marino       operator++()
1028*e4b17023SJohn Marino       {
1029*e4b17023SJohn Marino 	this->_M_incr();
1030*e4b17023SJohn Marino 	return *this;
1031*e4b17023SJohn Marino       }
1032*e4b17023SJohn Marino 
1033*e4b17023SJohn Marino       _Local_iterator
1034*e4b17023SJohn Marino       operator++(int)
1035*e4b17023SJohn Marino       {
1036*e4b17023SJohn Marino 	_Local_iterator __tmp(*this);
1037*e4b17023SJohn Marino 	this->_M_incr();
1038*e4b17023SJohn Marino 	return __tmp;
1039*e4b17023SJohn Marino       }
1040*e4b17023SJohn Marino     };
1041*e4b17023SJohn Marino 
1042*e4b17023SJohn Marino   template<typename _Key, typename _Value, typename _ExtractKey,
1043*e4b17023SJohn Marino 	   typename _H1, typename _H2, typename _Hash,
1044*e4b17023SJohn Marino 	   bool __constant_iterators, bool __cache>
1045*e4b17023SJohn Marino     struct _Local_const_iterator
1046*e4b17023SJohn Marino     : public _Local_iterator_base<_Key, _Value, _ExtractKey,
1047*e4b17023SJohn Marino 				  _H1, _H2, _Hash, __cache>
1048*e4b17023SJohn Marino     {
1049*e4b17023SJohn Marino       typedef _Value                                   value_type;
1050*e4b17023SJohn Marino       typedef const _Value*                            pointer;
1051*e4b17023SJohn Marino       typedef const _Value&                            reference;
1052*e4b17023SJohn Marino       typedef std::ptrdiff_t                           difference_type;
1053*e4b17023SJohn Marino       typedef std::forward_iterator_tag                iterator_category;
1054*e4b17023SJohn Marino 
1055*e4b17023SJohn Marino       _Local_const_iterator() = default;
1056*e4b17023SJohn Marino 
1057*e4b17023SJohn Marino       explicit
1058*e4b17023SJohn Marino       _Local_const_iterator(_Hash_node<_Value, __cache>* __p,
1059*e4b17023SJohn Marino 			    std::size_t __bkt, std::size_t __bkt_count)
1060*e4b17023SJohn Marino       : _Local_iterator_base<_Key, _Value, _ExtractKey, _H1, _H2, _Hash,
1061*e4b17023SJohn Marino 			     __cache>(__p, __bkt, __bkt_count)
1062*e4b17023SJohn Marino       { }
1063*e4b17023SJohn Marino 
1064*e4b17023SJohn Marino       _Local_const_iterator(const _Local_iterator<_Key, _Value, _ExtractKey,
1065*e4b17023SJohn Marino 						  _H1, _H2, _Hash,
1066*e4b17023SJohn Marino 						  __constant_iterators,
1067*e4b17023SJohn Marino 						  __cache>& __x)
1068*e4b17023SJohn Marino       : _Local_iterator_base<_Key, _Value, _ExtractKey, _H1, _H2, _Hash,
1069*e4b17023SJohn Marino 			     __cache>(__x._M_cur, __x._M_bucket,
1070*e4b17023SJohn Marino 				      __x._M_bucket_count)
1071*e4b17023SJohn Marino       { }
1072*e4b17023SJohn Marino 
1073*e4b17023SJohn Marino       reference
1074*e4b17023SJohn Marino       operator*() const
1075*e4b17023SJohn Marino       { return this->_M_cur->_M_v; }
1076*e4b17023SJohn Marino 
1077*e4b17023SJohn Marino       pointer
1078*e4b17023SJohn Marino       operator->() const
1079*e4b17023SJohn Marino       { return std::__addressof(this->_M_cur->_M_v); }
1080*e4b17023SJohn Marino 
1081*e4b17023SJohn Marino       _Local_const_iterator&
1082*e4b17023SJohn Marino       operator++()
1083*e4b17023SJohn Marino       {
1084*e4b17023SJohn Marino 	this->_M_incr();
1085*e4b17023SJohn Marino 	return *this;
1086*e4b17023SJohn Marino       }
1087*e4b17023SJohn Marino 
1088*e4b17023SJohn Marino       _Local_const_iterator
1089*e4b17023SJohn Marino       operator++(int)
1090*e4b17023SJohn Marino       {
1091*e4b17023SJohn Marino 	_Local_const_iterator __tmp(*this);
1092*e4b17023SJohn Marino 	this->_M_incr();
1093*e4b17023SJohn Marino 	return __tmp;
1094*e4b17023SJohn Marino       }
1095*e4b17023SJohn Marino     };
1096*e4b17023SJohn Marino 
1097*e4b17023SJohn Marino 
1098*e4b17023SJohn Marino   // Class template _Equality_base.  This is for implementing equality
1099*e4b17023SJohn Marino   // comparison for unordered containers, per N3068, by John Lakos and
1100*e4b17023SJohn Marino   // Pablo Halpern.  Algorithmically, we follow closely the reference
1101*e4b17023SJohn Marino   // implementations therein.
1102*e4b17023SJohn Marino   template<typename _ExtractKey, bool __unique_keys,
1103*e4b17023SJohn Marino 	   typename _Hashtable>
1104*e4b17023SJohn Marino     struct _Equality_base;
1105*e4b17023SJohn Marino 
1106*e4b17023SJohn Marino   template<typename _ExtractKey, typename _Hashtable>
1107*e4b17023SJohn Marino     struct _Equality_base<_ExtractKey, true, _Hashtable>
1108*e4b17023SJohn Marino     {
1109*e4b17023SJohn Marino       bool _M_equal(const _Hashtable&) const;
1110*e4b17023SJohn Marino     };
1111*e4b17023SJohn Marino 
1112*e4b17023SJohn Marino   template<typename _ExtractKey, typename _Hashtable>
1113*e4b17023SJohn Marino     bool
1114*e4b17023SJohn Marino     _Equality_base<_ExtractKey, true, _Hashtable>::
1115*e4b17023SJohn Marino     _M_equal(const _Hashtable& __other) const
1116*e4b17023SJohn Marino     {
1117*e4b17023SJohn Marino       const _Hashtable* __this = static_cast<const _Hashtable*>(this);
1118*e4b17023SJohn Marino 
1119*e4b17023SJohn Marino       if (__this->size() != __other.size())
1120*e4b17023SJohn Marino 	return false;
1121*e4b17023SJohn Marino 
1122*e4b17023SJohn Marino       for (auto __itx = __this->begin(); __itx != __this->end(); ++__itx)
1123*e4b17023SJohn Marino 	{
1124*e4b17023SJohn Marino 	  const auto __ity = __other.find(_ExtractKey()(*__itx));
1125*e4b17023SJohn Marino 	  if (__ity == __other.end() || !bool(*__ity == *__itx))
1126*e4b17023SJohn Marino 	    return false;
1127*e4b17023SJohn Marino 	}
1128*e4b17023SJohn Marino       return true;
1129*e4b17023SJohn Marino     }
1130*e4b17023SJohn Marino 
1131*e4b17023SJohn Marino   template<typename _ExtractKey, typename _Hashtable>
1132*e4b17023SJohn Marino     struct _Equality_base<_ExtractKey, false, _Hashtable>
1133*e4b17023SJohn Marino     {
1134*e4b17023SJohn Marino       bool _M_equal(const _Hashtable&) const;
1135*e4b17023SJohn Marino 
1136*e4b17023SJohn Marino     private:
1137*e4b17023SJohn Marino       template<typename _Uiterator>
1138*e4b17023SJohn Marino 	static bool
1139*e4b17023SJohn Marino 	_S_is_permutation(_Uiterator, _Uiterator, _Uiterator);
1140*e4b17023SJohn Marino     };
1141*e4b17023SJohn Marino 
1142*e4b17023SJohn Marino   // See std::is_permutation in N3068.
1143*e4b17023SJohn Marino   template<typename _ExtractKey, typename _Hashtable>
1144*e4b17023SJohn Marino     template<typename _Uiterator>
1145*e4b17023SJohn Marino       bool
1146*e4b17023SJohn Marino       _Equality_base<_ExtractKey, false, _Hashtable>::
1147*e4b17023SJohn Marino       _S_is_permutation(_Uiterator __first1, _Uiterator __last1,
1148*e4b17023SJohn Marino 			_Uiterator __first2)
1149*e4b17023SJohn Marino       {
1150*e4b17023SJohn Marino 	for (; __first1 != __last1; ++__first1, ++__first2)
1151*e4b17023SJohn Marino 	  if (!(*__first1 == *__first2))
1152*e4b17023SJohn Marino 	    break;
1153*e4b17023SJohn Marino 
1154*e4b17023SJohn Marino 	if (__first1 == __last1)
1155*e4b17023SJohn Marino 	  return true;
1156*e4b17023SJohn Marino 
1157*e4b17023SJohn Marino 	_Uiterator __last2 = __first2;
1158*e4b17023SJohn Marino 	std::advance(__last2, std::distance(__first1, __last1));
1159*e4b17023SJohn Marino 
1160*e4b17023SJohn Marino 	for (_Uiterator __it1 = __first1; __it1 != __last1; ++__it1)
1161*e4b17023SJohn Marino 	  {
1162*e4b17023SJohn Marino 	    _Uiterator __tmp =  __first1;
1163*e4b17023SJohn Marino 	    while (__tmp != __it1 && !bool(*__tmp == *__it1))
1164*e4b17023SJohn Marino 	      ++__tmp;
1165*e4b17023SJohn Marino 
1166*e4b17023SJohn Marino 	    // We've seen this one before.
1167*e4b17023SJohn Marino 	    if (__tmp != __it1)
1168*e4b17023SJohn Marino 	      continue;
1169*e4b17023SJohn Marino 
1170*e4b17023SJohn Marino 	    std::ptrdiff_t __n2 = 0;
1171*e4b17023SJohn Marino 	    for (__tmp = __first2; __tmp != __last2; ++__tmp)
1172*e4b17023SJohn Marino 	      if (*__tmp == *__it1)
1173*e4b17023SJohn Marino 		++__n2;
1174*e4b17023SJohn Marino 
1175*e4b17023SJohn Marino 	    if (!__n2)
1176*e4b17023SJohn Marino 	      return false;
1177*e4b17023SJohn Marino 
1178*e4b17023SJohn Marino 	    std::ptrdiff_t __n1 = 0;
1179*e4b17023SJohn Marino 	    for (__tmp = __it1; __tmp != __last1; ++__tmp)
1180*e4b17023SJohn Marino 	      if (*__tmp == *__it1)
1181*e4b17023SJohn Marino 		++__n1;
1182*e4b17023SJohn Marino 
1183*e4b17023SJohn Marino 	    if (__n1 != __n2)
1184*e4b17023SJohn Marino 	      return false;
1185*e4b17023SJohn Marino 	  }
1186*e4b17023SJohn Marino 	return true;
1187*e4b17023SJohn Marino       }
1188*e4b17023SJohn Marino 
1189*e4b17023SJohn Marino   template<typename _ExtractKey, typename _Hashtable>
1190*e4b17023SJohn Marino     bool
1191*e4b17023SJohn Marino     _Equality_base<_ExtractKey, false, _Hashtable>::
1192*e4b17023SJohn Marino     _M_equal(const _Hashtable& __other) const
1193*e4b17023SJohn Marino     {
1194*e4b17023SJohn Marino       const _Hashtable* __this = static_cast<const _Hashtable*>(this);
1195*e4b17023SJohn Marino 
1196*e4b17023SJohn Marino       if (__this->size() != __other.size())
1197*e4b17023SJohn Marino 	return false;
1198*e4b17023SJohn Marino 
1199*e4b17023SJohn Marino       for (auto __itx = __this->begin(); __itx != __this->end();)
1200*e4b17023SJohn Marino 	{
1201*e4b17023SJohn Marino 	  const auto __xrange = __this->equal_range(_ExtractKey()(*__itx));
1202*e4b17023SJohn Marino 	  const auto __yrange = __other.equal_range(_ExtractKey()(*__itx));
1203*e4b17023SJohn Marino 
1204*e4b17023SJohn Marino 	  if (std::distance(__xrange.first, __xrange.second)
1205*e4b17023SJohn Marino 	      != std::distance(__yrange.first, __yrange.second))
1206*e4b17023SJohn Marino 	    return false;
1207*e4b17023SJohn Marino 
1208*e4b17023SJohn Marino 	  if (!_S_is_permutation(__xrange.first,
1209*e4b17023SJohn Marino 				 __xrange.second,
1210*e4b17023SJohn Marino 				 __yrange.first))
1211*e4b17023SJohn Marino 	    return false;
1212*e4b17023SJohn Marino 
1213*e4b17023SJohn Marino 	  __itx = __xrange.second;
1214*e4b17023SJohn Marino 	}
1215*e4b17023SJohn Marino       return true;
1216*e4b17023SJohn Marino     }
1217*e4b17023SJohn Marino 
1218*e4b17023SJohn Marino _GLIBCXX_END_NAMESPACE_VERSION
1219*e4b17023SJohn Marino } // namespace __detail
1220*e4b17023SJohn Marino } // namespace std
1221*e4b17023SJohn Marino 
1222*e4b17023SJohn Marino #endif // _HASHTABLE_POLICY_H
1223