mingw/lib/gcc/mingw32/4.3.3/include/c++/parallel/sort.h

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2007, 2008 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 terms
   7 // of the GNU General Public License as published by the Free Software
   8 // Foundation; either version 2, or (at your option) any later
   9 // version.
  10
  11 // This library is distributed in the hope that it will be useful, but
  12 // WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 // General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License
  17 // along with this library; see the file COPYING.  If not, write to
  18 // the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
  19 // MA 02111-1307, USA.
  20
  21 // As a special exception, you may use this file as part of a free
  22 // software library without restriction.  Specifically, if other files
  23 // instantiate templates or use macros or inline functions from this
  24 // file, or you compile this file and link it with other files to
  25 // produce an executable, this file does not by itself cause the
  26 // resulting executable to be covered by the GNU General Public
  27 // License.  This exception does not however invalidate any other
  28 // reasons why the executable file might be covered by the GNU General
  29 // Public License.
  30
  31 /** @file parallel/sort.h
  32  *  @brief Parallel sorting algorithm switch.
  33  *  This file is a GNU parallel extension to the Standard C++ Library.
  34  */
  35
  36 // Written by Johannes Singler.
  37
  38 #ifndef _GLIBCXX_PARALLEL_SORT_H
  39 #define _GLIBCXX_PARALLEL_SORT_H 1
  40
  41 #include <parallel/basic_iterator.h>
  42 #include <parallel/features.h>
  43 #include <parallel/parallel.h>
  44
  45 #if _GLIBCXX_ASSERTIONS
  46 #include <parallel/checkers.h>
  47 #endif
  48
  49 #if _GLIBCXX_MERGESORT
  50 #include <parallel/multiway_mergesort.h>
  51 #endif
  52
  53 #if _GLIBCXX_QUICKSORT
  54 #include <parallel/quicksort.h>
  55 #endif
  56
  57 #if _GLIBCXX_BAL_QUICKSORT
  58 #include <parallel/balanced_quicksort.h>
  59 #endif
  60
  61 namespace __gnu_parallel
  62 {
  63   /**
  64    *  @brief Choose a parallel sorting algorithm.
  65    *  @param begin Begin iterator of input sequence.
  66    *  @param end End iterator of input sequence.
  67    *  @param comp Comparator.
  68    *  @param stable Sort stable.
  69    *  @callgraph
  70    */
  71   template<typename RandomAccessIterator, typename Comparator>
  72     inline void
  73     parallel_sort(RandomAccessIterator begin, RandomAccessIterator end,
  74                   Comparator comp, bool stable)
  75     {
  76       _GLIBCXX_CALL(end - begin)
  77       typedef std::iterator_traits<RandomAccessIterator> traits_type;
  78       typedef typename traits_type::value_type value_type;
  79       typedef typename traits_type::difference_type difference_type;
  80
  81       if (begin != end)
  82       {
  83         difference_type n = end - begin;
  84
  85         if (false) ;
  86 #if _GLIBCXX_MERGESORT
  87         else if (stable)
  88           {
  89             if(_Settings::get().sort_splitting == EXACT)
  90               parallel_sort_mwms<true, true>
  91                 (begin, end, comp, get_max_threads());
  92             else
  93               parallel_sort_mwms<true, false>
  94                 (begin, end, comp, get_max_threads());
  95           }
  96         else if (_Settings::get().sort_algorithm == MWMS)
  97           {
  98             if(_Settings::get().sort_splitting == EXACT)
  99               parallel_sort_mwms<false, true>
 100                 (begin, end, comp, get_max_threads());
 101             else
 102               parallel_sort_mwms<false, false>
 103                 (begin, end, comp, get_max_threads());
 104           }
 105 #endif
 106 #if _GLIBCXX_QUICKSORT
 107         else if (!stable && _Settings::get().sort_algorithm == QS)
 108           parallel_sort_qs(begin, end, comp, n, get_max_threads());
 109 #endif
 110 #if _GLIBCXX_BAL_QUICKSORT
 111         else if (!stable && _Settings::get().sort_algorithm == QS_BALANCED)
 112           parallel_sort_qsb(begin, end, comp, n, get_max_threads());
 113 #endif
 114         else if(stable)
 115           __gnu_sequential::stable_sort(begin, end, comp);
 116         else
 117           __gnu_sequential::sort(begin, end, comp);
 118       }
 119     }
 120 } // end namespace __gnu_parallel
 121
 122 #endif