deque.tcc

Go to the documentation of this file.

// Deque implementation (out of line) -*- C++ -*-

// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008,
// 2009, 2010, 2011
// Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.

// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
// <http://www.gnu.org/licenses/>.

/*
 *
 * Copyright (c) 1994
 * Hewlett-Packard Company
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Hewlett-Packard Company makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 *
 *
 * Copyright (c) 1997
 * Silicon Graphics Computer Systems, Inc.
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Silicon Graphics makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 */

/** @file bits/deque.tcc
 *  This is an internal header file, included by other library headers.
 *  Do not attempt to use it directly. @headername{deque}
 */

#ifndef _DEQUE_TCC
#define _DEQUE_TCC 1

namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_CONTAINER

#ifdef __GXX_EXPERIMENTAL_CXX0X__
  template <typename _Tp, typename _Alloc>
    void
    deque<_Tp, _Alloc>::
    _M_default_initialize()
    {
      _Map_pointer __cur;
      __try
        {
          for (__cur = this->_M_impl._M_start._M_node;
           __cur < this->_M_impl._M_finish._M_node;
           ++__cur)
            std::__uninitialized_default_a(*__cur, *__cur + _S_buffer_size(),
                       _M_get_Tp_allocator());
          std::__uninitialized_default_a(this->_M_impl._M_finish._M_first,
                     this->_M_impl._M_finish._M_cur,
                     _M_get_Tp_allocator());
        }
      __catch(...)
        {
          std::_Destroy(this->_M_impl._M_start, iterator(*__cur, __cur),
            _M_get_Tp_allocator());
          __throw_exception_again;
        }
    }
#endif

  template <typename _Tp, typename _Alloc>
    deque<_Tp, _Alloc>&
    deque<_Tp, _Alloc>::
    operator=(const deque& __x)
    {
      const size_type __len = size();
      if (&__x != this)
    {
      if (__len >= __x.size())
        _M_erase_at_end(std::copy(__x.begin(), __x.end(),
                      this->_M_impl._M_start));
      else
        {
          const_iterator __mid = __x.begin() + difference_type(__len);
          std::copy(__x.begin(), __mid, this->_M_impl._M_start);
          insert(this->_M_impl._M_finish, __mid, __x.end());
        }
    }
      return *this;
    }

#ifdef __GXX_EXPERIMENTAL_CXX0X__
  template<typename _Tp, typename _Alloc>
    template<typename... _Args>
      void
      deque<_Tp, _Alloc>::
      emplace_front(_Args&&... __args)
      {
    if (this->_M_impl._M_start._M_cur != this->_M_impl._M_start._M_first)
      {
        this->_M_impl.construct(this->_M_impl._M_start._M_cur - 1,
                    std::forward<_Args>(__args)...);
        --this->_M_impl._M_start._M_cur;
      }
    else
      _M_push_front_aux(std::forward<_Args>(__args)...);
      }

  template<typename _Tp, typename _Alloc>
    template<typename... _Args>
      void
      deque<_Tp, _Alloc>::
      emplace_back(_Args&&... __args)
      {
    if (this->_M_impl._M_finish._M_cur
        != this->_M_impl._M_finish._M_last - 1)
      {
        this->_M_impl.construct(this->_M_impl._M_finish._M_cur,
                    std::forward<_Args>(__args)...);
        ++this->_M_impl._M_finish._M_cur;
      }
    else
      _M_push_back_aux(std::forward<_Args>(__args)...);
      }
#endif

  template <typename _Tp, typename _Alloc>
    typename deque<_Tp, _Alloc>::iterator
    deque<_Tp, _Alloc>::
    insert(iterator __position, const value_type& __x)
    {
      if (__position._M_cur == this->_M_impl._M_start._M_cur)
    {
      push_front(__x);
      return this->_M_impl._M_start;
    }
      else if (__position._M_cur == this->_M_impl._M_finish._M_cur)
    {
      push_back(__x);
      iterator __tmp = this->_M_impl._M_finish;
      --__tmp;
      return __tmp;
    }
      else
        return _M_insert_aux(__position, __x);
    }

#ifdef __GXX_EXPERIMENTAL_CXX0X__
  template<typename _Tp, typename _Alloc>
    template<typename... _Args>
      typename deque<_Tp, _Alloc>::iterator
      deque<_Tp, _Alloc>::
      emplace(iterator __position, _Args&&... __args)
      {
    if (__position._M_cur == this->_M_impl._M_start._M_cur)
      {
        push_front(std::forward<_Args>(__args)...);
        return this->_M_impl._M_start;
      }
    else if (__position._M_cur == this->_M_impl._M_finish._M_cur)
      {
        push_back(std::forward<_Args>(__args)...);
        iterator __tmp = this->_M_impl._M_finish;
        --__tmp;
        return __tmp;
      }
    else
      return _M_insert_aux(__position, std::forward<_Args>(__args)...);
      }
#endif

  template <typename _Tp, typename _Alloc>
    typename deque<_Tp, _Alloc>::iterator
    deque<_Tp, _Alloc>::
    erase(iterator __position)
    {
      iterator __next = __position;
      ++__next;
      const difference_type __index = __position - begin();
      if (static_cast<size_type>(__index) < (size() >> 1))
    {
      if (__position != begin())
        _GLIBCXX_MOVE_BACKWARD3(begin(), __position, __next);
      pop_front();
    }
      else
    {
      if (__next != end())
        _GLIBCXX_MOVE3(__next, end(), __position);
      pop_back();
    }
      return begin() + __index;
    }

  template <typename _Tp, typename _Alloc>
    typename deque<_Tp, _Alloc>::iterator
    deque<_Tp, _Alloc>::
    erase(iterator __first, iterator __last)
    {
      if (__first == __last)
    return __first;
      else if (__first == begin() && __last == end())
    {
      clear();
      return end();
    }
      else
    {
      const difference_type __n = __last - __first;
      const difference_type __elems_before = __first - begin();
      if (static_cast<size_type>(__elems_before) <= (size() - __n) / 2)
        {
          if (__first != begin())
        _GLIBCXX_MOVE_BACKWARD3(begin(), __first, __last);
          _M_erase_at_begin(begin() + __n);
        }
      else
        {
          if (__last != end())
        _GLIBCXX_MOVE3(__last, end(), __first);
          _M_erase_at_end(end() - __n);
        }
      return begin() + __elems_before;
    }
    }

  template <typename _Tp, class _Alloc>
    template <typename _InputIterator>
      void
      deque<_Tp, _Alloc>::
      _M_assign_aux(_InputIterator __first, _InputIterator __last,
            std::input_iterator_tag)
      {
        iterator __cur = begin();
        for (; __first != __last && __cur != end(); ++__cur, ++__first)
          *__cur = *__first;
        if (__first == __last)
          _M_erase_at_end(__cur);
        else
          insert(end(), __first, __last);
      }

  template <typename _Tp, typename _Alloc>
    void
    deque<_Tp, _Alloc>::
    _M_fill_insert(iterator __pos, size_type __n, const value_type& __x)
    {
      if (__pos._M_cur == this->_M_impl._M_start._M_cur)
    {
      iterator __new_start = _M_reserve_elements_at_front(__n);
      __try
        {
          std::__uninitialized_fill_a(__new_start, this->_M_impl._M_start,
                      __x, _M_get_Tp_allocator());
          this->_M_impl._M_start = __new_start;
        }
      __catch(...)
        {
          _M_destroy_nodes(__new_start._M_node,
                   this->_M_impl._M_start._M_node);
          __throw_exception_again;
        }
    }
      else if (__pos._M_cur == this->_M_impl._M_finish._M_cur)
    {
      iterator __new_finish = _M_reserve_elements_at_back(__n);
      __try
        {
          std::__uninitialized_fill_a(this->_M_impl._M_finish,
                      __new_finish, __x,
                      _M_get_Tp_allocator());
          this->_M_impl._M_finish = __new_finish;
        }
      __catch(...)
        {
          _M_destroy_nodes(this->_M_impl._M_finish._M_node + 1,
                   __new_finish._M_node + 1);
          __throw_exception_again;
        }
    }
      else
        _M_insert_aux(__pos, __n, __x);
    }

#ifdef __GXX_EXPERIMENTAL_CXX0X__
  template <typename _Tp, typename _Alloc>
    void
    deque<_Tp, _Alloc>::
    _M_default_append(size_type __n)
    {
      if (__n)
    {
      iterator __new_finish = _M_reserve_elements_at_back(__n);
      __try
        {
          std::__uninitialized_default_a(this->_M_impl._M_finish,
                         __new_finish,
                         _M_get_Tp_allocator());
          this->_M_impl._M_finish = __new_finish;
        }
      __catch(...)
        {
          _M_destroy_nodes(this->_M_impl._M_finish._M_node + 1,
                   __new_finish._M_node + 1);
          __throw_exception_again;
        }
    }
    }

  template <typename _Tp, typename _Alloc>
    bool
    deque<_Tp, _Alloc>::
    _M_shrink_to_fit()
    {
      const difference_type __front_capacity
    = (this->_M_impl._M_start._M_cur - this->_M_impl._M_start._M_first);
      if (__front_capacity == 0)
    return false;

      const difference_type __back_capacity
    = (this->_M_impl._M_finish._M_last - this->_M_impl._M_finish._M_cur);
      if (__front_capacity + __back_capacity < _S_buffer_size())
    return false;

      return std::__shrink_to_fit_aux<deque>::_S_do_it(*this);
    }
#endif

  template <typename _Tp, typename _Alloc>
    void
    deque<_Tp, _Alloc>::
    _M_fill_initialize(const value_type& __value)
    {
      _Map_pointer __cur;
      __try
        {
          for (__cur = this->_M_impl._M_start._M_node;
           __cur < this->_M_impl._M_finish._M_node;
           ++__cur)
            std::__uninitialized_fill_a(*__cur, *__cur + _S_buffer_size(),
                    __value, _M_get_Tp_allocator());
          std::__uninitialized_fill_a(this->_M_impl._M_finish._M_first,
                      this->_M_impl._M_finish._M_cur,
                      __value, _M_get_Tp_allocator());
        }
      __catch(...)
        {
          std::_Destroy(this->_M_impl._M_start, iterator(*__cur, __cur),
            _M_get_Tp_allocator());
          __throw_exception_again;
        }
    }

  template <typename _Tp, typename _Alloc>
    template <typename _InputIterator>
      void
      deque<_Tp, _Alloc>::
      _M_range_initialize(_InputIterator __first, _InputIterator __last,
                          std::input_iterator_tag)
      {
        this->_M_initialize_map(0);
        __try
          {
            for (; __first != __last; ++__first)
              push_back(*__first);
          }
        __catch(...)
          {
            clear();
            __throw_exception_again;
          }
      }

  template <typename _Tp, typename _Alloc>
    template <typename _ForwardIterator>
      void
      deque<_Tp, _Alloc>::
      _M_range_initialize(_ForwardIterator __first, _ForwardIterator __last,
                          std::forward_iterator_tag)
      {
        const size_type __n = std::distance(__first, __last);
        this->_M_initialize_map(__n);

        _Map_pointer __cur_node;
        __try
          {
            for (__cur_node = this->_M_impl._M_start._M_node;
                 __cur_node < this->_M_impl._M_finish._M_node;
                 ++__cur_node)
          {
        _ForwardIterator __mid = __first;
        std::advance(__mid, _S_buffer_size());
        std::__uninitialized_copy_a(__first, __mid, *__cur_node,
                        _M_get_Tp_allocator());
        __first = __mid;
          }
            std::__uninitialized_copy_a(__first, __last,
                    this->_M_impl._M_finish._M_first,
                    _M_get_Tp_allocator());
          }
        __catch(...)
          {
            std::_Destroy(this->_M_impl._M_start,
              iterator(*__cur_node, __cur_node),
              _M_get_Tp_allocator());
            __throw_exception_again;
          }
      }

  // Called only if _M_impl._M_finish._M_cur == _M_impl._M_finish._M_last - 1.
  template<typename _Tp, typename _Alloc>
#ifdef __GXX_EXPERIMENTAL_CXX0X__
    template<typename... _Args>
      void
      deque<_Tp, _Alloc>::
      _M_push_back_aux(_Args&&... __args)
#else
      void
      deque<_Tp, _Alloc>::
      _M_push_back_aux(const value_type& __t)
#endif
      {
    _M_reserve_map_at_back();
    *(this->_M_impl._M_finish._M_node + 1) = this->_M_allocate_node();
    __try
      {
#ifdef __GXX_EXPERIMENTAL_CXX0X__
        this->_M_impl.construct(this->_M_impl._M_finish._M_cur,
                    std::forward<_Args>(__args)...);
#else
        this->_M_impl.construct(this->_M_impl._M_finish._M_cur, __t);
#endif
        this->_M_impl._M_finish._M_set_node(this->_M_impl._M_finish._M_node
                        + 1);
        this->_M_impl._M_finish._M_cur = this->_M_impl._M_finish._M_first;
      }
    __catch(...)
      {
        _M_deallocate_node(*(this->_M_impl._M_finish._M_node + 1));
        __throw_exception_again;
      }
      }

  // Called only if _M_impl._M_start._M_cur == _M_impl._M_start._M_first.
  template<typename _Tp, typename _Alloc>
#ifdef __GXX_EXPERIMENTAL_CXX0X__
    template<typename... _Args>
      void
      deque<_Tp, _Alloc>::
      _M_push_front_aux(_Args&&... __args)
#else
      void
      deque<_Tp, _Alloc>::
      _M_push_front_aux(const value_type& __t)
#endif
      {
    _M_reserve_map_at_front();
    *(this->_M_impl._M_start._M_node - 1) = this->_M_allocate_node();
    __try
      {
        this->_M_impl._M_start._M_set_node(this->_M_impl._M_start._M_node
                           - 1);
        this->_M_impl._M_start._M_cur = this->_M_impl._M_start._M_last - 1;
#ifdef __GXX_EXPERIMENTAL_CXX0X__
        this->_M_impl.construct(this->_M_impl._M_start._M_cur,
                    std::forward<_Args>(__args)...);
#else
        this->_M_impl.construct(this->_M_impl._M_start._M_cur, __t);
#endif
      }
    __catch(...)
      {
        ++this->_M_impl._M_start;
        _M_deallocate_node(*(this->_M_impl._M_start._M_node - 1));
        __throw_exception_again;
      }
      }

  // Called only if _M_impl._M_finish._M_cur == _M_impl._M_finish._M_first.
  template <typename _Tp, typename _Alloc>
    void deque<_Tp, _Alloc>::
    _M_pop_back_aux()
    {
      _M_deallocate_node(this->_M_impl._M_finish._M_first);
      this->_M_impl._M_finish._M_set_node(this->_M_impl._M_finish._M_node - 1);
      this->_M_impl._M_finish._M_cur = this->_M_impl._M_finish._M_last - 1;
      this->_M_impl.destroy(this->_M_impl._M_finish._M_cur);
    }

  // Called only if _M_impl._M_start._M_cur == _M_impl._M_start._M_last - 1.
  // Note that if the deque has at least one element (a precondition for this
  // member function), and if
  //   _M_impl._M_start._M_cur == _M_impl._M_start._M_last,
  // then the deque must have at least two nodes.
  template <typename _Tp, typename _Alloc>
    void deque<_Tp, _Alloc>::
    _M_pop_front_aux()
    {
      this->_M_impl.destroy(this->_M_impl._M_start._M_cur);
      _M_deallocate_node(this->_M_impl._M_start._M_first);
      this->_M_impl._M_start._M_set_node(this->_M_impl._M_start._M_node + 1);
      this->_M_impl._M_start._M_cur = this->_M_impl._M_start._M_first;
    }

  template <typename _Tp, typename _Alloc>
    template <typename _InputIterator>
      void
      deque<_Tp, _Alloc>::
      _M_range_insert_aux(iterator __pos,
                          _InputIterator __first, _InputIterator __last,
                          std::input_iterator_tag)
      { std::copy(__first, __last, std::inserter(*this, __pos)); }

  template <typename _Tp, typename _Alloc>
    template <typename _ForwardIterator>
      void
      deque<_Tp, _Alloc>::
      _M_range_insert_aux(iterator __pos,
                          _ForwardIterator __first, _ForwardIterator __last,
                          std::forward_iterator_tag)
      {
        const size_type __n = std::distance(__first, __last);
        if (__pos._M_cur == this->_M_impl._M_start._M_cur)
      {
        iterator __new_start = _M_reserve_elements_at_front(__n);
        __try
          {
        std::__uninitialized_copy_a(__first, __last, __new_start,
                        _M_get_Tp_allocator());
        this->_M_impl._M_start = __new_start;
          }
        __catch(...)
          {
        _M_destroy_nodes(__new_start._M_node,
                 this->_M_impl._M_start._M_node);
        __throw_exception_again;
          }
      }
        else if (__pos._M_cur == this->_M_impl._M_finish._M_cur)
      {
        iterator __new_finish = _M_reserve_elements_at_back(__n);
        __try
          {
        std::__uninitialized_copy_a(__first, __last,
                        this->_M_impl._M_finish,
                        _M_get_Tp_allocator());
        this->_M_impl._M_finish = __new_finish;
          }
        __catch(...)
          {
        _M_destroy_nodes(this->_M_impl._M_finish._M_node + 1,
                 __new_finish._M_node + 1);
        __throw_exception_again;
          }
      }
        else
          _M_insert_aux(__pos, __first, __last, __n);
      }

  template<typename _Tp, typename _Alloc>
#ifdef __GXX_EXPERIMENTAL_CXX0X__
    template<typename... _Args>
      typename deque<_Tp, _Alloc>::iterator
      deque<_Tp, _Alloc>::
      _M_insert_aux(iterator __pos, _Args&&... __args)
      {
    value_type __x_copy(std::forward<_Args>(__args)...); // XXX copy
#else
    typename deque<_Tp, _Alloc>::iterator
      deque<_Tp, _Alloc>::
      _M_insert_aux(iterator __pos, const value_type& __x)
      {
    value_type __x_copy = __x; // XXX copy
#endif
    difference_type __index = __pos - this->_M_impl._M_start;
    if (static_cast<size_type>(__index) < size() / 2)
      {
        push_front(_GLIBCXX_MOVE(front()));
        iterator __front1 = this->_M_impl._M_start;
        ++__front1;
        iterator __front2 = __front1;
        ++__front2;
        __pos = this->_M_impl._M_start + __index;
        iterator __pos1 = __pos;
        ++__pos1;
        _GLIBCXX_MOVE3(__front2, __pos1, __front1);
      }
    else
      {
        push_back(_GLIBCXX_MOVE(back()));
        iterator __back1 = this->_M_impl._M_finish;
        --__back1;
        iterator __back2 = __back1;
        --__back2;
        __pos = this->_M_impl._M_start + __index;
        _GLIBCXX_MOVE_BACKWARD3(__pos, __back2, __back1);
      }
    *__pos = _GLIBCXX_MOVE(__x_copy);
    return __pos;
      }

  template <typename _Tp, typename _Alloc>
    void
    deque<_Tp, _Alloc>::
    _M_insert_aux(iterator __pos, size_type __n, const value_type& __x)
    {
      const difference_type __elems_before = __pos - this->_M_impl._M_start;
      const size_type __length = this->size();
      value_type __x_copy = __x;
      if (__elems_before < difference_type(__length / 2))
    {
      iterator __new_start = _M_reserve_elements_at_front(__n);
      iterator __old_start = this->_M_impl._M_start;
      __pos = this->_M_impl._M_start + __elems_before;
      __try
        {
          if (__elems_before >= difference_type(__n))
        {
          iterator __start_n = (this->_M_impl._M_start
                    + difference_type(__n));
          std::__uninitialized_move_a(this->_M_impl._M_start,
                          __start_n, __new_start,
                          _M_get_Tp_allocator());
          this->_M_impl._M_start = __new_start;
          _GLIBCXX_MOVE3(__start_n, __pos, __old_start);
          std::fill(__pos - difference_type(__n), __pos, __x_copy);
        }
          else
        {
          std::__uninitialized_move_fill(this->_M_impl._M_start,
                         __pos, __new_start,
                         this->_M_impl._M_start,
                         __x_copy,
                         _M_get_Tp_allocator());
          this->_M_impl._M_start = __new_start;
          std::fill(__old_start, __pos, __x_copy);
        }
        }
      __catch(...)
        {
          _M_destroy_nodes(__new_start._M_node,
                   this->_M_impl._M_start._M_node);
          __throw_exception_again;
        }
    }
      else
    {
      iterator __new_finish = _M_reserve_elements_at_back(__n);
      iterator __old_finish = this->_M_impl._M_finish;
      const difference_type __elems_after =
        difference_type(__length) - __elems_before;
      __pos = this->_M_impl._M_finish - __elems_after;
      __try
        {
          if (__elems_after > difference_type(__n))
        {
          iterator __finish_n = (this->_M_impl._M_finish
                     - difference_type(__n));
          std::__uninitialized_move_a(__finish_n,
                          this->_M_impl._M_finish,
                          this->_M_impl._M_finish,
                          _M_get_Tp_allocator());
          this->_M_impl._M_finish = __new_finish;
          _GLIBCXX_MOVE_BACKWARD3(__pos, __finish_n, __old_finish);
          std::fill(__pos, __pos + difference_type(__n), __x_copy);
        }
          else
        {
          std::__uninitialized_fill_move(this->_M_impl._M_finish,
                         __pos + difference_type(__n),
                         __x_copy, __pos,
                         this->_M_impl._M_finish,
                         _M_get_Tp_allocator());
          this->_M_impl._M_finish = __new_finish;
          std::fill(__pos, __old_finish, __x_copy);
        }
        }
      __catch(...)
        {
          _M_destroy_nodes(this->_M_impl._M_finish._M_node + 1,
                   __new_finish._M_node + 1);
          __throw_exception_again;
        }
    }
    }

  template <typename _Tp, typename _Alloc>
    template <typename _ForwardIterator>
      void
      deque<_Tp, _Alloc>::
      _M_insert_aux(iterator __pos,
                    _ForwardIterator __first, _ForwardIterator __last,
                    size_type __n)
      {
        const difference_type __elemsbefore = __pos - this->_M_impl._M_start;
        const size_type __length = size();
        if (static_cast<size_type>(__elemsbefore) < __length / 2)
      {
        iterator __new_start = _M_reserve_elements_at_front(__n);
        iterator __old_start = this->_M_impl._M_start;
        __pos = this->_M_impl._M_start + __elemsbefore;
        __try
          {
        if (__elemsbefore >= difference_type(__n))
          {
            iterator __start_n = (this->_M_impl._M_start
                      + difference_type(__n));
            std::__uninitialized_move_a(this->_M_impl._M_start,
                        __start_n, __new_start,
                        _M_get_Tp_allocator());
            this->_M_impl._M_start = __new_start;
            _GLIBCXX_MOVE3(__start_n, __pos, __old_start);
            std::copy(__first, __last, __pos - difference_type(__n));
          }
        else
          {
            _ForwardIterator __mid = __first;
            std::advance(__mid, difference_type(__n) - __elemsbefore);
            std::__uninitialized_move_copy(this->_M_impl._M_start,
                           __pos, __first, __mid,
                           __new_start,
                           _M_get_Tp_allocator());
            this->_M_impl._M_start = __new_start;
            std::copy(__mid, __last, __old_start);
          }
          }
        __catch(...)
          {
        _M_destroy_nodes(__new_start._M_node,
                 this->_M_impl._M_start._M_node);
        __throw_exception_again;
          }
      }
        else
        {
          iterator __new_finish = _M_reserve_elements_at_back(__n);
          iterator __old_finish = this->_M_impl._M_finish;
          const difference_type __elemsafter =
            difference_type(__length) - __elemsbefore;
          __pos = this->_M_impl._M_finish - __elemsafter;
          __try
            {
              if (__elemsafter > difference_type(__n))
        {
          iterator __finish_n = (this->_M_impl._M_finish
                     - difference_type(__n));
          std::__uninitialized_move_a(__finish_n,
                          this->_M_impl._M_finish,
                          this->_M_impl._M_finish,
                          _M_get_Tp_allocator());
          this->_M_impl._M_finish = __new_finish;
          _GLIBCXX_MOVE_BACKWARD3(__pos, __finish_n, __old_finish);
          std::copy(__first, __last, __pos);
        }
              else
        {
          _ForwardIterator __mid = __first;
          std::advance(__mid, __elemsafter);
          std::__uninitialized_copy_move(__mid, __last, __pos,
                         this->_M_impl._M_finish,
                         this->_M_impl._M_finish,
                         _M_get_Tp_allocator());
          this->_M_impl._M_finish = __new_finish;
          std::copy(__first, __mid, __pos);
        }
            }
          __catch(...)
            {
              _M_destroy_nodes(this->_M_impl._M_finish._M_node + 1,
                   __new_finish._M_node + 1);
              __throw_exception_again;
            }
        }
      }

   template<typename _Tp, typename _Alloc>
     void
     deque<_Tp, _Alloc>::
     _M_destroy_data_aux(iterator __first, iterator __last)
     {
       for (_Map_pointer __node = __first._M_node + 1;
        __node < __last._M_node; ++__node)
     std::_Destroy(*__node, *__node + _S_buffer_size(),
               _M_get_Tp_allocator());

       if (__first._M_node != __last._M_node)
     {
       std::_Destroy(__first._M_cur, __first._M_last,
             _M_get_Tp_allocator());
       std::_Destroy(__last._M_first, __last._M_cur,
             _M_get_Tp_allocator());
     }
       else
     std::_Destroy(__first._M_cur, __last._M_cur,
               _M_get_Tp_allocator());
     }

  template <typename _Tp, typename _Alloc>
    void
    deque<_Tp, _Alloc>::
    _M_new_elements_at_front(size_type __new_elems)
    {
      if (this->max_size() - this->size() < __new_elems)
    __throw_length_error(__N("deque::_M_new_elements_at_front"));

      const size_type __new_nodes = ((__new_elems + _S_buffer_size() - 1)
                     / _S_buffer_size());
      _M_reserve_map_at_front(__new_nodes);
      size_type __i;
      __try
        {
          for (__i = 1; __i <= __new_nodes; ++__i)
            *(this->_M_impl._M_start._M_node - __i) = this->_M_allocate_node();
        }
      __catch(...)
        {
          for (size_type __j = 1; __j < __i; ++__j)
            _M_deallocate_node(*(this->_M_impl._M_start._M_node - __j));
          __throw_exception_again;
        }
    }

  template <typename _Tp, typename _Alloc>
    void
    deque<_Tp, _Alloc>::
    _M_new_elements_at_back(size_type __new_elems)
    {
      if (this->max_size() - this->size() < __new_elems)
    __throw_length_error(__N("deque::_M_new_elements_at_back"));

      const size_type __new_nodes = ((__new_elems + _S_buffer_size() - 1)
                     / _S_buffer_size());
      _M_reserve_map_at_back(__new_nodes);
      size_type __i;
      __try
        {
          for (__i = 1; __i <= __new_nodes; ++__i)
            *(this->_M_impl._M_finish._M_node + __i) = this->_M_allocate_node();
        }
      __catch(...)
        {
          for (size_type __j = 1; __j < __i; ++__j)
            _M_deallocate_node(*(this->_M_impl._M_finish._M_node + __j));
          __throw_exception_again;
        }
    }

  template <typename _Tp, typename _Alloc>
    void
    deque<_Tp, _Alloc>::
    _M_reallocate_map(size_type __nodes_to_add, bool __add_at_front)
    {
      const size_type __old_num_nodes
    = this->_M_impl._M_finish._M_node - this->_M_impl._M_start._M_node + 1;
      const size_type __new_num_nodes = __old_num_nodes + __nodes_to_add;

      _Map_pointer __new_nstart;
      if (this->_M_impl._M_map_size > 2 * __new_num_nodes)
    {
      __new_nstart = this->_M_impl._M_map + (this->_M_impl._M_map_size
                     - __new_num_nodes) / 2
                     + (__add_at_front ? __nodes_to_add : 0);
      if (__new_nstart < this->_M_impl._M_start._M_node)
        std::copy(this->_M_impl._M_start._M_node,
              this->_M_impl._M_finish._M_node + 1,
              __new_nstart);
      else
        std::copy_backward(this->_M_impl._M_start._M_node,
                   this->_M_impl._M_finish._M_node + 1,
                   __new_nstart + __old_num_nodes);
    }
      else
    {
      size_type __new_map_size = this->_M_impl._M_map_size
                                 + std::max(this->_M_impl._M_map_size,
                        __nodes_to_add) + 2;

      _Map_pointer __new_map = this->_M_allocate_map(__new_map_size);
      __new_nstart = __new_map + (__new_map_size - __new_num_nodes) / 2
                     + (__add_at_front ? __nodes_to_add : 0);
      std::copy(this->_M_impl._M_start._M_node,
            this->_M_impl._M_finish._M_node + 1,
            __new_nstart);
      _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size);

      this->_M_impl._M_map = __new_map;
      this->_M_impl._M_map_size = __new_map_size;
    }

      this->_M_impl._M_start._M_set_node(__new_nstart);
      this->_M_impl._M_finish._M_set_node(__new_nstart + __old_num_nodes - 1);
    }

  // Overload for deque::iterators, exploiting the "segmented-iterator
  // optimization".
  template<typename _Tp>
    void
    fill(const _Deque_iterator<_Tp, _Tp&, _Tp*>& __first,
     const _Deque_iterator<_Tp, _Tp&, _Tp*>& __last, const _Tp& __value)
    {
      typedef typename _Deque_iterator<_Tp, _Tp&, _Tp*>::_Self _Self;

      for (typename _Self::_Map_pointer __node = __first._M_node + 1;
           __node < __last._M_node; ++__node)
    std::fill(*__node, *__node + _Self::_S_buffer_size(), __value);

      if (__first._M_node != __last._M_node)
    {
      std::fill(__first._M_cur, __first._M_last, __value);
      std::fill(__last._M_first, __last._M_cur, __value);
    }
      else
    std::fill(__first._M_cur, __last._M_cur, __value);
    }

  template<typename _Tp>
    _Deque_iterator<_Tp, _Tp&, _Tp*>
    copy(_Deque_iterator<_Tp, const _Tp&, const _Tp*> __first,
     _Deque_iterator<_Tp, const _Tp&, const _Tp*> __last,
     _Deque_iterator<_Tp, _Tp&, _Tp*> __result)
    {
      typedef typename _Deque_iterator<_Tp, _Tp&, _Tp*>::_Self _Self;
      typedef typename _Self::difference_type difference_type;

      difference_type __len = __last - __first;
      while (__len > 0)
    {
      const difference_type __clen
        = std::min(__len, std::min(__first._M_last - __first._M_cur,
                       __result._M_last - __result._M_cur));
      std::copy(__first._M_cur, __first._M_cur + __clen, __result._M_cur);
      __first += __clen;
      __result += __clen;
      __len -= __clen;
    }
      return __result;
    }

  template<typename _Tp>
    _Deque_iterator<_Tp, _Tp&, _Tp*>
    copy_backward(_Deque_iterator<_Tp, const _Tp&, const _Tp*> __first,
          _Deque_iterator<_Tp, const _Tp&, const _Tp*> __last,
          _Deque_iterator<_Tp, _Tp&, _Tp*> __result)
    {
      typedef typename _Deque_iterator<_Tp, _Tp&, _Tp*>::_Self _Self;
      typedef typename _Self::difference_type difference_type;

      difference_type __len = __last - __first;
      while (__len > 0)
    {
      difference_type __llen = __last._M_cur - __last._M_first;
      _Tp* __lend = __last._M_cur;

      difference_type __rlen = __result._M_cur - __result._M_first;
      _Tp* __rend = __result._M_cur;

      if (!__llen)
        {
          __llen = _Self::_S_buffer_size();
          __lend = *(__last._M_node - 1) + __llen;
        }
      if (!__rlen)
        {
          __rlen = _Self::_S_buffer_size();
          __rend = *(__result._M_node - 1) + __rlen;
        }

      const difference_type __clen = std::min(__len,
                          std::min(__llen, __rlen));
      std::copy_backward(__lend - __clen, __lend, __rend);
      __last -= __clen;
      __result -= __clen;
      __len -= __clen;
    }
      return __result;
    }

#ifdef __GXX_EXPERIMENTAL_CXX0X__
  template<typename _Tp>
    _Deque_iterator<_Tp, _Tp&, _Tp*>
    move(_Deque_iterator<_Tp, const _Tp&, const _Tp*> __first,
     _Deque_iterator<_Tp, const _Tp&, const _Tp*> __last,
     _Deque_iterator<_Tp, _Tp&, _Tp*> __result)
    {
      typedef typename _Deque_iterator<_Tp, _Tp&, _Tp*>::_Self _Self;
      typedef typename _Self::difference_type difference_type;

      difference_type __len = __last - __first;
      while (__len > 0)
    {
      const difference_type __clen
        = std::min(__len, std::min(__first._M_last - __first._M_cur,
                       __result._M_last - __result._M_cur));
      std::move(__first._M_cur, __first._M_cur + __clen, __result._M_cur);
      __first += __clen;
      __result += __clen;
      __len -= __clen;
    }
      return __result;
    }

  template<typename _Tp>
    _Deque_iterator<_Tp, _Tp&, _Tp*>
    move_backward(_Deque_iterator<_Tp, const _Tp&, const _Tp*> __first,
          _Deque_iterator<_Tp, const _Tp&, const _Tp*> __last,
          _Deque_iterator<_Tp, _Tp&, _Tp*> __result)
    {
      typedef typename _Deque_iterator<_Tp, _Tp&, _Tp*>::_Self _Self;
      typedef typename _Self::difference_type difference_type;

      difference_type __len = __last - __first;
      while (__len > 0)
    {
      difference_type __llen = __last._M_cur - __last._M_first;
      _Tp* __lend = __last._M_cur;

      difference_type __rlen = __result._M_cur - __result._M_first;
      _Tp* __rend = __result._M_cur;

      if (!__llen)
        {
          __llen = _Self::_S_buffer_size();
          __lend = *(__last._M_node - 1) + __llen;
        }
      if (!__rlen)
        {
          __rlen = _Self::_S_buffer_size();
          __rend = *(__result._M_node - 1) + __rlen;
        }

      const difference_type __clen = std::min(__len,
                          std::min(__llen, __rlen));
      std::move_backward(__lend - __clen, __lend, __rend);
      __last -= __clen;
      __result -= __clen;
      __len -= __clen;
    }
      return __result;
    }
#endif

_GLIBCXX_END_NAMESPACE_CONTAINER
} // namespace std

#endif