1 // Deque implementation (out of line) -*- C++ -*-
2 
3 // Copyright (C) 2001-2018 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 /*
26  *
27  * Copyright (c) 1994
28  * Hewlett-Packard Company
29  *
30  * Permission to use, copy, modify, distribute and sell this software
31  * and its documentation for any purpose is hereby granted without fee,
32  * provided that the above copyright notice appear in all copies and
33  * that both that copyright notice and this permission notice appear
34  * in supporting documentation.  Hewlett-Packard Company makes no
35  * representations about the suitability of this software for any
36  * purpose.  It is provided "as is" without express or implied warranty.
37  *
38  *
39  * Copyright (c) 1997
40  * Silicon Graphics Computer Systems, Inc.
41  *
42  * Permission to use, copy, modify, distribute and sell this software
43  * and its documentation for any purpose is hereby granted without fee,
44  * provided that the above copyright notice appear in all copies and
45  * that both that copyright notice and this permission notice appear
46  * in supporting documentation.  Silicon Graphics makes no
47  * representations about the suitability of this software for any
48  * purpose.  It is provided "as is" without express or implied warranty.
49  */
50 
51 /** @file bits/deque.tcc
52  *  This is an internal header file, included by other library headers.
53  *  Do not attempt to use it directly. @headername{deque}
54  */
55 
56 #ifndef _DEQUE_TCC
57 #define _DEQUE_TCC 1
58 
59 namespace std _GLIBCXX_VISIBILITY(default)
60 {
61 _GLIBCXX_BEGIN_NAMESPACE_VERSION
62 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
63 
64 #if __cplusplus >= 201103L
65   template <typename _Tp, typename _Alloc>
66     void
67     deque<_Tp, _Alloc>::
68     _M_default_initialize()
69     {
70       _Map_pointer __cur;
71       __try
72         {
73           for (__cur = this->_M_impl._M_start._M_node;
74 	       __cur < this->_M_impl._M_finish._M_node;
75 	       ++__cur)
76             std::__uninitialized_default_a(*__cur, *__cur + _S_buffer_size(),
77 					   _M_get_Tp_allocator());
78           std::__uninitialized_default_a(this->_M_impl._M_finish._M_first,
79 					 this->_M_impl._M_finish._M_cur,
80 					 _M_get_Tp_allocator());
81         }
82       __catch(...)
83         {
84           std::_Destroy(this->_M_impl._M_start, iterator(*__cur, __cur),
85 			_M_get_Tp_allocator());
86           __throw_exception_again;
87         }
88     }
89 #endif
90 
91   template <typename _Tp, typename _Alloc>
92     deque<_Tp, _Alloc>&
93     deque<_Tp, _Alloc>::
94     operator=(const deque& __x)
95     {
96       if (&__x != this)
97 	{
98 #if __cplusplus >= 201103L
99 	  if (_Alloc_traits::_S_propagate_on_copy_assign())
100 	    {
101 	      if (!_Alloc_traits::_S_always_equal()
102 	          && _M_get_Tp_allocator() != __x._M_get_Tp_allocator())
103 	        {
104 		  // Replacement allocator cannot free existing storage,
105 		  // so deallocate everything and take copy of __x's data.
106 		  _M_replace_map(__x, __x.get_allocator());
107 		  std::__alloc_on_copy(_M_get_Tp_allocator(),
108 				       __x._M_get_Tp_allocator());
109 		  return *this;
110 		}
111 	      std::__alloc_on_copy(_M_get_Tp_allocator(),
112 				   __x._M_get_Tp_allocator());
113 	    }
114 #endif
115 	  const size_type __len = size();
116 	  if (__len >= __x.size())
117 	    _M_erase_at_end(std::copy(__x.begin(), __x.end(),
118 				      this->_M_impl._M_start));
119 	  else
120 	    {
121 	      const_iterator __mid = __x.begin() + difference_type(__len);
122 	      std::copy(__x.begin(), __mid, this->_M_impl._M_start);
123 	      _M_range_insert_aux(this->_M_impl._M_finish, __mid, __x.end(),
124 				  std::random_access_iterator_tag());
125 	    }
126 	}
127       return *this;
128     }
129 
130 #if __cplusplus >= 201103L
131   template<typename _Tp, typename _Alloc>
132     template<typename... _Args>
133 #if __cplusplus > 201402L
134       typename deque<_Tp, _Alloc>::reference
135 #else
136       void
137 #endif
138       deque<_Tp, _Alloc>::
139       emplace_front(_Args&&... __args)
140       {
141 	if (this->_M_impl._M_start._M_cur != this->_M_impl._M_start._M_first)
142 	  {
143 	    _Alloc_traits::construct(this->_M_impl,
144 	                             this->_M_impl._M_start._M_cur - 1,
145 			             std::forward<_Args>(__args)...);
146 	    --this->_M_impl._M_start._M_cur;
147 	  }
148 	else
149 	  _M_push_front_aux(std::forward<_Args>(__args)...);
150 #if __cplusplus > 201402L
151 	return front();
152 #endif
153       }
154 
155   template<typename _Tp, typename _Alloc>
156     template<typename... _Args>
157 #if __cplusplus > 201402L
158       typename deque<_Tp, _Alloc>::reference
159 #else
160       void
161 #endif
162       deque<_Tp, _Alloc>::
163       emplace_back(_Args&&... __args)
164       {
165 	if (this->_M_impl._M_finish._M_cur
166 	    != this->_M_impl._M_finish._M_last - 1)
167 	  {
168 	    _Alloc_traits::construct(this->_M_impl,
169 	                             this->_M_impl._M_finish._M_cur,
170 			             std::forward<_Args>(__args)...);
171 	    ++this->_M_impl._M_finish._M_cur;
172 	  }
173 	else
174 	  _M_push_back_aux(std::forward<_Args>(__args)...);
175 #if __cplusplus > 201402L
176 	return back();
177 #endif
178       }
179 #endif
180 
181 #if __cplusplus >= 201103L
182   template<typename _Tp, typename _Alloc>
183     template<typename... _Args>
184       typename deque<_Tp, _Alloc>::iterator
185       deque<_Tp, _Alloc>::
186       emplace(const_iterator __position, _Args&&... __args)
187       {
188 	if (__position._M_cur == this->_M_impl._M_start._M_cur)
189 	  {
190 	    emplace_front(std::forward<_Args>(__args)...);
191 	    return this->_M_impl._M_start;
192 	  }
193 	else if (__position._M_cur == this->_M_impl._M_finish._M_cur)
194 	  {
195 	    emplace_back(std::forward<_Args>(__args)...);
196 	    iterator __tmp = this->_M_impl._M_finish;
197 	    --__tmp;
198 	    return __tmp;
199 	  }
200 	else
201 	  return _M_insert_aux(__position._M_const_cast(),
202 			       std::forward<_Args>(__args)...);
203       }
204 #endif
205 
206   template <typename _Tp, typename _Alloc>
207     typename deque<_Tp, _Alloc>::iterator
208     deque<_Tp, _Alloc>::
209 #if __cplusplus >= 201103L
210     insert(const_iterator __position, const value_type& __x)
211 #else
212     insert(iterator __position, const value_type& __x)
213 #endif
214     {
215       if (__position._M_cur == this->_M_impl._M_start._M_cur)
216 	{
217 	  push_front(__x);
218 	  return this->_M_impl._M_start;
219 	}
220       else if (__position._M_cur == this->_M_impl._M_finish._M_cur)
221 	{
222 	  push_back(__x);
223 	  iterator __tmp = this->_M_impl._M_finish;
224 	  --__tmp;
225 	  return __tmp;
226 	}
227       else
228 	return _M_insert_aux(__position._M_const_cast(), __x);
229    }
230 
231   template <typename _Tp, typename _Alloc>
232     typename deque<_Tp, _Alloc>::iterator
233     deque<_Tp, _Alloc>::
234     _M_erase(iterator __position)
235     {
236       iterator __next = __position;
237       ++__next;
238       const difference_type __index = __position - begin();
239       if (static_cast<size_type>(__index) < (size() >> 1))
240 	{
241 	  if (__position != begin())
242 	    _GLIBCXX_MOVE_BACKWARD3(begin(), __position, __next);
243 	  pop_front();
244 	}
245       else
246 	{
247 	  if (__next != end())
248 	    _GLIBCXX_MOVE3(__next, end(), __position);
249 	  pop_back();
250 	}
251       return begin() + __index;
252     }
253 
254   template <typename _Tp, typename _Alloc>
255     typename deque<_Tp, _Alloc>::iterator
256     deque<_Tp, _Alloc>::
257     _M_erase(iterator __first, iterator __last)
258     {
259       if (__first == __last)
260 	return __first;
261       else if (__first == begin() && __last == end())
262 	{
263 	  clear();
264 	  return end();
265 	}
266       else
267 	{
268 	  const difference_type __n = __last - __first;
269 	  const difference_type __elems_before = __first - begin();
270 	  if (static_cast<size_type>(__elems_before) <= (size() - __n) / 2)
271 	    {
272 	      if (__first != begin())
273 		_GLIBCXX_MOVE_BACKWARD3(begin(), __first, __last);
274 	      _M_erase_at_begin(begin() + __n);
275 	    }
276 	  else
277 	    {
278 	      if (__last != end())
279 		_GLIBCXX_MOVE3(__last, end(), __first);
280 	      _M_erase_at_end(end() - __n);
281 	    }
282 	  return begin() + __elems_before;
283 	}
284     }
285 
286   template <typename _Tp, class _Alloc>
287     template <typename _InputIterator>
288       void
289       deque<_Tp, _Alloc>::
290       _M_assign_aux(_InputIterator __first, _InputIterator __last,
291 		    std::input_iterator_tag)
292       {
293         iterator __cur = begin();
294         for (; __first != __last && __cur != end(); ++__cur, ++__first)
295           *__cur = *__first;
296         if (__first == __last)
297           _M_erase_at_end(__cur);
298         else
299           _M_range_insert_aux(end(), __first, __last,
300 			      std::__iterator_category(__first));
301       }
302 
303   template <typename _Tp, typename _Alloc>
304     void
305     deque<_Tp, _Alloc>::
306     _M_fill_insert(iterator __pos, size_type __n, const value_type& __x)
307     {
308       if (__pos._M_cur == this->_M_impl._M_start._M_cur)
309 	{
310 	  iterator __new_start = _M_reserve_elements_at_front(__n);
311 	  __try
312 	    {
313 	      std::__uninitialized_fill_a(__new_start, this->_M_impl._M_start,
314 					  __x, _M_get_Tp_allocator());
315 	      this->_M_impl._M_start = __new_start;
316 	    }
317 	  __catch(...)
318 	    {
319 	      _M_destroy_nodes(__new_start._M_node,
320 			       this->_M_impl._M_start._M_node);
321 	      __throw_exception_again;
322 	    }
323 	}
324       else if (__pos._M_cur == this->_M_impl._M_finish._M_cur)
325 	{
326 	  iterator __new_finish = _M_reserve_elements_at_back(__n);
327 	  __try
328 	    {
329 	      std::__uninitialized_fill_a(this->_M_impl._M_finish,
330 					  __new_finish, __x,
331 					  _M_get_Tp_allocator());
332 	      this->_M_impl._M_finish = __new_finish;
333 	    }
334 	  __catch(...)
335 	    {
336 	      _M_destroy_nodes(this->_M_impl._M_finish._M_node + 1,
337 			       __new_finish._M_node + 1);
338 	      __throw_exception_again;
339 	    }
340 	}
341       else
342         _M_insert_aux(__pos, __n, __x);
343     }
344 
345 #if __cplusplus >= 201103L
346   template <typename _Tp, typename _Alloc>
347     void
348     deque<_Tp, _Alloc>::
349     _M_default_append(size_type __n)
350     {
351       if (__n)
352 	{
353 	  iterator __new_finish = _M_reserve_elements_at_back(__n);
354 	  __try
355 	    {
356 	      std::__uninitialized_default_a(this->_M_impl._M_finish,
357 					     __new_finish,
358 					     _M_get_Tp_allocator());
359 	      this->_M_impl._M_finish = __new_finish;
360 	    }
361 	  __catch(...)
362 	    {
363 	      _M_destroy_nodes(this->_M_impl._M_finish._M_node + 1,
364 			       __new_finish._M_node + 1);
365 	      __throw_exception_again;
366 	    }
367 	}
368     }
369 
370   template <typename _Tp, typename _Alloc>
371     bool
372     deque<_Tp, _Alloc>::
373     _M_shrink_to_fit()
374     {
375       const difference_type __front_capacity
376 	= (this->_M_impl._M_start._M_cur - this->_M_impl._M_start._M_first);
377       if (__front_capacity == 0)
378 	return false;
379 
380       const difference_type __back_capacity
381 	= (this->_M_impl._M_finish._M_last - this->_M_impl._M_finish._M_cur);
382       if (__front_capacity + __back_capacity < _S_buffer_size())
383 	return false;
384 
385       return std::__shrink_to_fit_aux<deque>::_S_do_it(*this);
386     }
387 #endif
388 
389   template <typename _Tp, typename _Alloc>
390     void
391     deque<_Tp, _Alloc>::
392     _M_fill_initialize(const value_type& __value)
393     {
394       _Map_pointer __cur;
395       __try
396         {
397           for (__cur = this->_M_impl._M_start._M_node;
398 	       __cur < this->_M_impl._M_finish._M_node;
399 	       ++__cur)
400             std::__uninitialized_fill_a(*__cur, *__cur + _S_buffer_size(),
401 					__value, _M_get_Tp_allocator());
402           std::__uninitialized_fill_a(this->_M_impl._M_finish._M_first,
403 				      this->_M_impl._M_finish._M_cur,
404 				      __value, _M_get_Tp_allocator());
405         }
406       __catch(...)
407         {
408           std::_Destroy(this->_M_impl._M_start, iterator(*__cur, __cur),
409 			_M_get_Tp_allocator());
410           __throw_exception_again;
411         }
412     }
413 
414   template <typename _Tp, typename _Alloc>
415     template <typename _InputIterator>
416       void
417       deque<_Tp, _Alloc>::
418       _M_range_initialize(_InputIterator __first, _InputIterator __last,
419                           std::input_iterator_tag)
420       {
421         this->_M_initialize_map(0);
422         __try
423           {
424             for (; __first != __last; ++__first)
425 #if __cplusplus >= 201103L
426 	      emplace_back(*__first);
427 #else
428               push_back(*__first);
429 #endif
430           }
431         __catch(...)
432           {
433             clear();
434             __throw_exception_again;
435           }
436       }
437 
438   template <typename _Tp, typename _Alloc>
439     template <typename _ForwardIterator>
440       void
441       deque<_Tp, _Alloc>::
442       _M_range_initialize(_ForwardIterator __first, _ForwardIterator __last,
443                           std::forward_iterator_tag)
444       {
445         const size_type __n = std::distance(__first, __last);
446         this->_M_initialize_map(__n);
447 
448         _Map_pointer __cur_node;
449         __try
450           {
451             for (__cur_node = this->_M_impl._M_start._M_node;
452                  __cur_node < this->_M_impl._M_finish._M_node;
453                  ++__cur_node)
454 	      {
455 		_ForwardIterator __mid = __first;
456 		std::advance(__mid, _S_buffer_size());
457 		std::__uninitialized_copy_a(__first, __mid, *__cur_node,
458 					    _M_get_Tp_allocator());
459 		__first = __mid;
460 	      }
461             std::__uninitialized_copy_a(__first, __last,
462 					this->_M_impl._M_finish._M_first,
463 					_M_get_Tp_allocator());
464           }
465         __catch(...)
466           {
467             std::_Destroy(this->_M_impl._M_start,
468 			  iterator(*__cur_node, __cur_node),
469 			  _M_get_Tp_allocator());
470             __throw_exception_again;
471           }
472       }
473 
474   // Called only if _M_impl._M_finish._M_cur == _M_impl._M_finish._M_last - 1.
475   template<typename _Tp, typename _Alloc>
476 #if __cplusplus >= 201103L
477     template<typename... _Args>
478       void
479       deque<_Tp, _Alloc>::
480       _M_push_back_aux(_Args&&... __args)
481 #else
482       void
483       deque<_Tp, _Alloc>::
484       _M_push_back_aux(const value_type& __t)
485 #endif
486       {
487 	_M_reserve_map_at_back();
488 	*(this->_M_impl._M_finish._M_node + 1) = this->_M_allocate_node();
489 	__try
490 	  {
491 #if __cplusplus >= 201103L
492 	    _Alloc_traits::construct(this->_M_impl,
493 	                             this->_M_impl._M_finish._M_cur,
494 			             std::forward<_Args>(__args)...);
495 #else
496 	    this->_M_impl.construct(this->_M_impl._M_finish._M_cur, __t);
497 #endif
498 	    this->_M_impl._M_finish._M_set_node(this->_M_impl._M_finish._M_node
499 						+ 1);
500 	    this->_M_impl._M_finish._M_cur = this->_M_impl._M_finish._M_first;
501 	  }
502 	__catch(...)
503 	  {
504 	    _M_deallocate_node(*(this->_M_impl._M_finish._M_node + 1));
505 	    __throw_exception_again;
506 	  }
507       }
508 
509   // Called only if _M_impl._M_start._M_cur == _M_impl._M_start._M_first.
510   template<typename _Tp, typename _Alloc>
511 #if __cplusplus >= 201103L
512     template<typename... _Args>
513       void
514       deque<_Tp, _Alloc>::
515       _M_push_front_aux(_Args&&... __args)
516 #else
517       void
518       deque<_Tp, _Alloc>::
519       _M_push_front_aux(const value_type& __t)
520 #endif
521       {
522 	_M_reserve_map_at_front();
523 	*(this->_M_impl._M_start._M_node - 1) = this->_M_allocate_node();
524 	__try
525 	  {
526 	    this->_M_impl._M_start._M_set_node(this->_M_impl._M_start._M_node
527 					       - 1);
528 	    this->_M_impl._M_start._M_cur = this->_M_impl._M_start._M_last - 1;
529 #if __cplusplus >= 201103L
530 	    _Alloc_traits::construct(this->_M_impl,
531 	                             this->_M_impl._M_start._M_cur,
532 			             std::forward<_Args>(__args)...);
533 #else
534 	    this->_M_impl.construct(this->_M_impl._M_start._M_cur, __t);
535 #endif
536 	  }
537 	__catch(...)
538 	  {
539 	    ++this->_M_impl._M_start;
540 	    _M_deallocate_node(*(this->_M_impl._M_start._M_node - 1));
541 	    __throw_exception_again;
542 	  }
543       }
544 
545   // Called only if _M_impl._M_finish._M_cur == _M_impl._M_finish._M_first.
546   template <typename _Tp, typename _Alloc>
547     void deque<_Tp, _Alloc>::
548     _M_pop_back_aux()
549     {
550       _M_deallocate_node(this->_M_impl._M_finish._M_first);
551       this->_M_impl._M_finish._M_set_node(this->_M_impl._M_finish._M_node - 1);
552       this->_M_impl._M_finish._M_cur = this->_M_impl._M_finish._M_last - 1;
553       _Alloc_traits::destroy(_M_get_Tp_allocator(),
554 			     this->_M_impl._M_finish._M_cur);
555     }
556 
557   // Called only if _M_impl._M_start._M_cur == _M_impl._M_start._M_last - 1.
558   // Note that if the deque has at least one element (a precondition for this
559   // member function), and if
560   //   _M_impl._M_start._M_cur == _M_impl._M_start._M_last,
561   // then the deque must have at least two nodes.
562   template <typename _Tp, typename _Alloc>
563     void deque<_Tp, _Alloc>::
564     _M_pop_front_aux()
565     {
566       _Alloc_traits::destroy(_M_get_Tp_allocator(),
567 			     this->_M_impl._M_start._M_cur);
568       _M_deallocate_node(this->_M_impl._M_start._M_first);
569       this->_M_impl._M_start._M_set_node(this->_M_impl._M_start._M_node + 1);
570       this->_M_impl._M_start._M_cur = this->_M_impl._M_start._M_first;
571     }
572 
573   template <typename _Tp, typename _Alloc>
574     template <typename _InputIterator>
575       void
576       deque<_Tp, _Alloc>::
577       _M_range_insert_aux(iterator __pos,
578                           _InputIterator __first, _InputIterator __last,
579                           std::input_iterator_tag)
580       { std::copy(__first, __last, std::inserter(*this, __pos)); }
581 
582   template <typename _Tp, typename _Alloc>
583     template <typename _ForwardIterator>
584       void
585       deque<_Tp, _Alloc>::
586       _M_range_insert_aux(iterator __pos,
587                           _ForwardIterator __first, _ForwardIterator __last,
588                           std::forward_iterator_tag)
589       {
590         const size_type __n = std::distance(__first, __last);
591         if (__pos._M_cur == this->_M_impl._M_start._M_cur)
592 	  {
593 	    iterator __new_start = _M_reserve_elements_at_front(__n);
594 	    __try
595 	      {
596 		std::__uninitialized_copy_a(__first, __last, __new_start,
597 					    _M_get_Tp_allocator());
598 		this->_M_impl._M_start = __new_start;
599 	      }
600 	    __catch(...)
601 	      {
602 		_M_destroy_nodes(__new_start._M_node,
603 				 this->_M_impl._M_start._M_node);
604 		__throw_exception_again;
605 	      }
606 	  }
607         else if (__pos._M_cur == this->_M_impl._M_finish._M_cur)
608 	  {
609 	    iterator __new_finish = _M_reserve_elements_at_back(__n);
610 	    __try
611 	      {
612 		std::__uninitialized_copy_a(__first, __last,
613 					    this->_M_impl._M_finish,
614 					    _M_get_Tp_allocator());
615 		this->_M_impl._M_finish = __new_finish;
616 	      }
617 	    __catch(...)
618 	      {
619 		_M_destroy_nodes(this->_M_impl._M_finish._M_node + 1,
620 				 __new_finish._M_node + 1);
621 		__throw_exception_again;
622 	      }
623 	  }
624         else
625           _M_insert_aux(__pos, __first, __last, __n);
626       }
627 
628   template<typename _Tp, typename _Alloc>
629 #if __cplusplus >= 201103L
630     template<typename... _Args>
631       typename deque<_Tp, _Alloc>::iterator
632       deque<_Tp, _Alloc>::
633       _M_insert_aux(iterator __pos, _Args&&... __args)
634       {
635 	value_type __x_copy(std::forward<_Args>(__args)...); // XXX copy
636 #else
637     typename deque<_Tp, _Alloc>::iterator
638       deque<_Tp, _Alloc>::
639       _M_insert_aux(iterator __pos, const value_type& __x)
640       {
641 	value_type __x_copy = __x; // XXX copy
642 #endif
643 	difference_type __index = __pos - this->_M_impl._M_start;
644 	if (static_cast<size_type>(__index) < size() / 2)
645 	  {
646 	    push_front(_GLIBCXX_MOVE(front()));
647 	    iterator __front1 = this->_M_impl._M_start;
648 	    ++__front1;
649 	    iterator __front2 = __front1;
650 	    ++__front2;
651 	    __pos = this->_M_impl._M_start + __index;
652 	    iterator __pos1 = __pos;
653 	    ++__pos1;
654 	    _GLIBCXX_MOVE3(__front2, __pos1, __front1);
655 	  }
656 	else
657 	  {
658 	    push_back(_GLIBCXX_MOVE(back()));
659 	    iterator __back1 = this->_M_impl._M_finish;
660 	    --__back1;
661 	    iterator __back2 = __back1;
662 	    --__back2;
663 	    __pos = this->_M_impl._M_start + __index;
664 	    _GLIBCXX_MOVE_BACKWARD3(__pos, __back2, __back1);
665 	  }
666 	*__pos = _GLIBCXX_MOVE(__x_copy);
667 	return __pos;
668       }
669 
670   template <typename _Tp, typename _Alloc>
671     void
672     deque<_Tp, _Alloc>::
673     _M_insert_aux(iterator __pos, size_type __n, const value_type& __x)
674     {
675       const difference_type __elems_before = __pos - this->_M_impl._M_start;
676       const size_type __length = this->size();
677       value_type __x_copy = __x;
678       if (__elems_before < difference_type(__length / 2))
679 	{
680 	  iterator __new_start = _M_reserve_elements_at_front(__n);
681 	  iterator __old_start = this->_M_impl._M_start;
682 	  __pos = this->_M_impl._M_start + __elems_before;
683 	  __try
684 	    {
685 	      if (__elems_before >= difference_type(__n))
686 		{
687 		  iterator __start_n = (this->_M_impl._M_start
688 					+ difference_type(__n));
689 		  std::__uninitialized_move_a(this->_M_impl._M_start,
690 					      __start_n, __new_start,
691 					      _M_get_Tp_allocator());
692 		  this->_M_impl._M_start = __new_start;
693 		  _GLIBCXX_MOVE3(__start_n, __pos, __old_start);
694 		  std::fill(__pos - difference_type(__n), __pos, __x_copy);
695 		}
696 	      else
697 		{
698 		  std::__uninitialized_move_fill(this->_M_impl._M_start,
699 						 __pos, __new_start,
700 						 this->_M_impl._M_start,
701 						 __x_copy,
702 						 _M_get_Tp_allocator());
703 		  this->_M_impl._M_start = __new_start;
704 		  std::fill(__old_start, __pos, __x_copy);
705 		}
706 	    }
707 	  __catch(...)
708 	    {
709 	      _M_destroy_nodes(__new_start._M_node,
710 			       this->_M_impl._M_start._M_node);
711 	      __throw_exception_again;
712 	    }
713 	}
714       else
715 	{
716 	  iterator __new_finish = _M_reserve_elements_at_back(__n);
717 	  iterator __old_finish = this->_M_impl._M_finish;
718 	  const difference_type __elems_after =
719 	    difference_type(__length) - __elems_before;
720 	  __pos = this->_M_impl._M_finish - __elems_after;
721 	  __try
722 	    {
723 	      if (__elems_after > difference_type(__n))
724 		{
725 		  iterator __finish_n = (this->_M_impl._M_finish
726 					 - difference_type(__n));
727 		  std::__uninitialized_move_a(__finish_n,
728 					      this->_M_impl._M_finish,
729 					      this->_M_impl._M_finish,
730 					      _M_get_Tp_allocator());
731 		  this->_M_impl._M_finish = __new_finish;
732 		  _GLIBCXX_MOVE_BACKWARD3(__pos, __finish_n, __old_finish);
733 		  std::fill(__pos, __pos + difference_type(__n), __x_copy);
734 		}
735 	      else
736 		{
737 		  std::__uninitialized_fill_move(this->_M_impl._M_finish,
738 						 __pos + difference_type(__n),
739 						 __x_copy, __pos,
740 						 this->_M_impl._M_finish,
741 						 _M_get_Tp_allocator());
742 		  this->_M_impl._M_finish = __new_finish;
743 		  std::fill(__pos, __old_finish, __x_copy);
744 		}
745 	    }
746 	  __catch(...)
747 	    {
748 	      _M_destroy_nodes(this->_M_impl._M_finish._M_node + 1,
749 			       __new_finish._M_node + 1);
750 	      __throw_exception_again;
751 	    }
752 	}
753     }
754 
755   template <typename _Tp, typename _Alloc>
756     template <typename _ForwardIterator>
757       void
758       deque<_Tp, _Alloc>::
759       _M_insert_aux(iterator __pos,
760                     _ForwardIterator __first, _ForwardIterator __last,
761                     size_type __n)
762       {
763         const difference_type __elemsbefore = __pos - this->_M_impl._M_start;
764         const size_type __length = size();
765         if (static_cast<size_type>(__elemsbefore) < __length / 2)
766 	  {
767 	    iterator __new_start = _M_reserve_elements_at_front(__n);
768 	    iterator __old_start = this->_M_impl._M_start;
769 	    __pos = this->_M_impl._M_start + __elemsbefore;
770 	    __try
771 	      {
772 		if (__elemsbefore >= difference_type(__n))
773 		  {
774 		    iterator __start_n = (this->_M_impl._M_start
775 					  + difference_type(__n));
776 		    std::__uninitialized_move_a(this->_M_impl._M_start,
777 						__start_n, __new_start,
778 						_M_get_Tp_allocator());
779 		    this->_M_impl._M_start = __new_start;
780 		    _GLIBCXX_MOVE3(__start_n, __pos, __old_start);
781 		    std::copy(__first, __last, __pos - difference_type(__n));
782 		  }
783 		else
784 		  {
785 		    _ForwardIterator __mid = __first;
786 		    std::advance(__mid, difference_type(__n) - __elemsbefore);
787 		    std::__uninitialized_move_copy(this->_M_impl._M_start,
788 						   __pos, __first, __mid,
789 						   __new_start,
790 						   _M_get_Tp_allocator());
791 		    this->_M_impl._M_start = __new_start;
792 		    std::copy(__mid, __last, __old_start);
793 		  }
794 	      }
795 	    __catch(...)
796 	      {
797 		_M_destroy_nodes(__new_start._M_node,
798 				 this->_M_impl._M_start._M_node);
799 		__throw_exception_again;
800 	      }
801 	  }
802         else
803         {
804           iterator __new_finish = _M_reserve_elements_at_back(__n);
805           iterator __old_finish = this->_M_impl._M_finish;
806           const difference_type __elemsafter =
807             difference_type(__length) - __elemsbefore;
808           __pos = this->_M_impl._M_finish - __elemsafter;
809           __try
810             {
811               if (__elemsafter > difference_type(__n))
812 		{
813 		  iterator __finish_n = (this->_M_impl._M_finish
814 					 - difference_type(__n));
815 		  std::__uninitialized_move_a(__finish_n,
816 					      this->_M_impl._M_finish,
817 					      this->_M_impl._M_finish,
818 					      _M_get_Tp_allocator());
819 		  this->_M_impl._M_finish = __new_finish;
820 		  _GLIBCXX_MOVE_BACKWARD3(__pos, __finish_n, __old_finish);
821 		  std::copy(__first, __last, __pos);
822 		}
823               else
824 		{
825 		  _ForwardIterator __mid = __first;
826 		  std::advance(__mid, __elemsafter);
827 		  std::__uninitialized_copy_move(__mid, __last, __pos,
828 						 this->_M_impl._M_finish,
829 						 this->_M_impl._M_finish,
830 						 _M_get_Tp_allocator());
831 		  this->_M_impl._M_finish = __new_finish;
832 		  std::copy(__first, __mid, __pos);
833 		}
834             }
835           __catch(...)
836             {
837               _M_destroy_nodes(this->_M_impl._M_finish._M_node + 1,
838 			       __new_finish._M_node + 1);
839               __throw_exception_again;
840             }
841         }
842       }
843 
844    template<typename _Tp, typename _Alloc>
845      void
846      deque<_Tp, _Alloc>::
847      _M_destroy_data_aux(iterator __first, iterator __last)
848      {
849        for (_Map_pointer __node = __first._M_node + 1;
850 	    __node < __last._M_node; ++__node)
851 	 std::_Destroy(*__node, *__node + _S_buffer_size(),
852 		       _M_get_Tp_allocator());
853 
854        if (__first._M_node != __last._M_node)
855 	 {
856 	   std::_Destroy(__first._M_cur, __first._M_last,
857 			 _M_get_Tp_allocator());
858 	   std::_Destroy(__last._M_first, __last._M_cur,
859 			 _M_get_Tp_allocator());
860 	 }
861        else
862 	 std::_Destroy(__first._M_cur, __last._M_cur,
863 		       _M_get_Tp_allocator());
864      }
865 
866   template <typename _Tp, typename _Alloc>
867     void
868     deque<_Tp, _Alloc>::
869     _M_new_elements_at_front(size_type __new_elems)
870     {
871       if (this->max_size() - this->size() < __new_elems)
872 	__throw_length_error(__N("deque::_M_new_elements_at_front"));
873 
874       const size_type __new_nodes = ((__new_elems + _S_buffer_size() - 1)
875 				     / _S_buffer_size());
876       _M_reserve_map_at_front(__new_nodes);
877       size_type __i;
878       __try
879         {
880           for (__i = 1; __i <= __new_nodes; ++__i)
881             *(this->_M_impl._M_start._M_node - __i) = this->_M_allocate_node();
882         }
883       __catch(...)
884         {
885           for (size_type __j = 1; __j < __i; ++__j)
886             _M_deallocate_node(*(this->_M_impl._M_start._M_node - __j));
887           __throw_exception_again;
888         }
889     }
890 
891   template <typename _Tp, typename _Alloc>
892     void
893     deque<_Tp, _Alloc>::
894     _M_new_elements_at_back(size_type __new_elems)
895     {
896       if (this->max_size() - this->size() < __new_elems)
897 	__throw_length_error(__N("deque::_M_new_elements_at_back"));
898 
899       const size_type __new_nodes = ((__new_elems + _S_buffer_size() - 1)
900 				     / _S_buffer_size());
901       _M_reserve_map_at_back(__new_nodes);
902       size_type __i;
903       __try
904         {
905           for (__i = 1; __i <= __new_nodes; ++__i)
906             *(this->_M_impl._M_finish._M_node + __i) = this->_M_allocate_node();
907         }
908       __catch(...)
909         {
910           for (size_type __j = 1; __j < __i; ++__j)
911             _M_deallocate_node(*(this->_M_impl._M_finish._M_node + __j));
912           __throw_exception_again;
913         }
914     }
915 
916   template <typename _Tp, typename _Alloc>
917     void
918     deque<_Tp, _Alloc>::
919     _M_reallocate_map(size_type __nodes_to_add, bool __add_at_front)
920     {
921       const size_type __old_num_nodes
922 	= this->_M_impl._M_finish._M_node - this->_M_impl._M_start._M_node + 1;
923       const size_type __new_num_nodes = __old_num_nodes + __nodes_to_add;
924 
925       _Map_pointer __new_nstart;
926       if (this->_M_impl._M_map_size > 2 * __new_num_nodes)
927 	{
928 	  __new_nstart = this->_M_impl._M_map + (this->_M_impl._M_map_size
929 					 - __new_num_nodes) / 2
930 	                 + (__add_at_front ? __nodes_to_add : 0);
931 	  if (__new_nstart < this->_M_impl._M_start._M_node)
932 	    std::copy(this->_M_impl._M_start._M_node,
933 		      this->_M_impl._M_finish._M_node + 1,
934 		      __new_nstart);
935 	  else
936 	    std::copy_backward(this->_M_impl._M_start._M_node,
937 			       this->_M_impl._M_finish._M_node + 1,
938 			       __new_nstart + __old_num_nodes);
939 	}
940       else
941 	{
942 	  size_type __new_map_size = this->_M_impl._M_map_size
943 	                             + std::max(this->_M_impl._M_map_size,
944 						__nodes_to_add) + 2;
945 
946 	  _Map_pointer __new_map = this->_M_allocate_map(__new_map_size);
947 	  __new_nstart = __new_map + (__new_map_size - __new_num_nodes) / 2
948 	                 + (__add_at_front ? __nodes_to_add : 0);
949 	  std::copy(this->_M_impl._M_start._M_node,
950 		    this->_M_impl._M_finish._M_node + 1,
951 		    __new_nstart);
952 	  _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size);
953 
954 	  this->_M_impl._M_map = __new_map;
955 	  this->_M_impl._M_map_size = __new_map_size;
956 	}
957 
958       this->_M_impl._M_start._M_set_node(__new_nstart);
959       this->_M_impl._M_finish._M_set_node(__new_nstart + __old_num_nodes - 1);
960     }
961 
962   // Overload for deque::iterators, exploiting the "segmented-iterator
963   // optimization".
964   template<typename _Tp>
965     void
966     fill(const _Deque_iterator<_Tp, _Tp&, _Tp*>& __first,
967 	 const _Deque_iterator<_Tp, _Tp&, _Tp*>& __last, const _Tp& __value)
968     {
969       typedef typename _Deque_iterator<_Tp, _Tp&, _Tp*>::_Self _Self;
970 
971       for (typename _Self::_Map_pointer __node = __first._M_node + 1;
972            __node < __last._M_node; ++__node)
973 	std::fill(*__node, *__node + _Self::_S_buffer_size(), __value);
974 
975       if (__first._M_node != __last._M_node)
976 	{
977 	  std::fill(__first._M_cur, __first._M_last, __value);
978 	  std::fill(__last._M_first, __last._M_cur, __value);
979 	}
980       else
981 	std::fill(__first._M_cur, __last._M_cur, __value);
982     }
983 
984   template<typename _Tp>
985     _Deque_iterator<_Tp, _Tp&, _Tp*>
986     copy(_Deque_iterator<_Tp, const _Tp&, const _Tp*> __first,
987 	 _Deque_iterator<_Tp, const _Tp&, const _Tp*> __last,
988 	 _Deque_iterator<_Tp, _Tp&, _Tp*> __result)
989     {
990       typedef typename _Deque_iterator<_Tp, _Tp&, _Tp*>::_Self _Self;
991       typedef typename _Self::difference_type difference_type;
992 
993       difference_type __len = __last - __first;
994       while (__len > 0)
995 	{
996 	  const difference_type __clen
997 	    = std::min(__len, std::min(__first._M_last - __first._M_cur,
998 				       __result._M_last - __result._M_cur));
999 	  std::copy(__first._M_cur, __first._M_cur + __clen, __result._M_cur);
1000 	  __first += __clen;
1001 	  __result += __clen;
1002 	  __len -= __clen;
1003 	}
1004       return __result;
1005     }
1006 
1007   template<typename _Tp>
1008     _Deque_iterator<_Tp, _Tp&, _Tp*>
1009     copy_backward(_Deque_iterator<_Tp, const _Tp&, const _Tp*> __first,
1010 		  _Deque_iterator<_Tp, const _Tp&, const _Tp*> __last,
1011 		  _Deque_iterator<_Tp, _Tp&, _Tp*> __result)
1012     {
1013       typedef typename _Deque_iterator<_Tp, _Tp&, _Tp*>::_Self _Self;
1014       typedef typename _Self::difference_type difference_type;
1015 
1016       difference_type __len = __last - __first;
1017       while (__len > 0)
1018 	{
1019 	  difference_type __llen = __last._M_cur - __last._M_first;
1020 	  _Tp* __lend = __last._M_cur;
1021 
1022 	  difference_type __rlen = __result._M_cur - __result._M_first;
1023 	  _Tp* __rend = __result._M_cur;
1024 
1025 	  if (!__llen)
1026 	    {
1027 	      __llen = _Self::_S_buffer_size();
1028 	      __lend = *(__last._M_node - 1) + __llen;
1029 	    }
1030 	  if (!__rlen)
1031 	    {
1032 	      __rlen = _Self::_S_buffer_size();
1033 	      __rend = *(__result._M_node - 1) + __rlen;
1034 	    }
1035 
1036 	  const difference_type __clen = std::min(__len,
1037 						  std::min(__llen, __rlen));
1038 	  std::copy_backward(__lend - __clen, __lend, __rend);
1039 	  __last -= __clen;
1040 	  __result -= __clen;
1041 	  __len -= __clen;
1042 	}
1043       return __result;
1044     }
1045 
1046 #if __cplusplus >= 201103L
1047   template<typename _Tp>
1048     _Deque_iterator<_Tp, _Tp&, _Tp*>
1049     move(_Deque_iterator<_Tp, const _Tp&, const _Tp*> __first,
1050 	 _Deque_iterator<_Tp, const _Tp&, const _Tp*> __last,
1051 	 _Deque_iterator<_Tp, _Tp&, _Tp*> __result)
1052     {
1053       typedef typename _Deque_iterator<_Tp, _Tp&, _Tp*>::_Self _Self;
1054       typedef typename _Self::difference_type difference_type;
1055 
1056       difference_type __len = __last - __first;
1057       while (__len > 0)
1058 	{
1059 	  const difference_type __clen
1060 	    = std::min(__len, std::min(__first._M_last - __first._M_cur,
1061 				       __result._M_last - __result._M_cur));
1062 	  std::move(__first._M_cur, __first._M_cur + __clen, __result._M_cur);
1063 	  __first += __clen;
1064 	  __result += __clen;
1065 	  __len -= __clen;
1066 	}
1067       return __result;
1068     }
1069 
1070   template<typename _Tp>
1071     _Deque_iterator<_Tp, _Tp&, _Tp*>
1072     move_backward(_Deque_iterator<_Tp, const _Tp&, const _Tp*> __first,
1073 		  _Deque_iterator<_Tp, const _Tp&, const _Tp*> __last,
1074 		  _Deque_iterator<_Tp, _Tp&, _Tp*> __result)
1075     {
1076       typedef typename _Deque_iterator<_Tp, _Tp&, _Tp*>::_Self _Self;
1077       typedef typename _Self::difference_type difference_type;
1078 
1079       difference_type __len = __last - __first;
1080       while (__len > 0)
1081 	{
1082 	  difference_type __llen = __last._M_cur - __last._M_first;
1083 	  _Tp* __lend = __last._M_cur;
1084 
1085 	  difference_type __rlen = __result._M_cur - __result._M_first;
1086 	  _Tp* __rend = __result._M_cur;
1087 
1088 	  if (!__llen)
1089 	    {
1090 	      __llen = _Self::_S_buffer_size();
1091 	      __lend = *(__last._M_node - 1) + __llen;
1092 	    }
1093 	  if (!__rlen)
1094 	    {
1095 	      __rlen = _Self::_S_buffer_size();
1096 	      __rend = *(__result._M_node - 1) + __rlen;
1097 	    }
1098 
1099 	  const difference_type __clen = std::min(__len,
1100 						  std::min(__llen, __rlen));
1101 	  std::move_backward(__lend - __clen, __lend, __rend);
1102 	  __last -= __clen;
1103 	  __result -= __clen;
1104 	  __len -= __clen;
1105 	}
1106       return __result;
1107     }
1108 #endif
1109 
1110 _GLIBCXX_END_NAMESPACE_CONTAINER
1111 _GLIBCXX_END_NAMESPACE_VERSION
1112 } // namespace std
1113 
1114 #endif
1115