1 // -*- C++ -*- 2 3 // Copyright (C) 2007-2013 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 3, 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 // 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 * @file parallel/tags.h 27 * @brief Tags for compile-time selection. 28 * This file is a GNU parallel extension to the Standard C++ Library. 29 */ 30 31 // Written by Johannes Singler and Felix Putze. 32 33 #ifndef _GLIBCXX_PARALLEL_TAGS_H 34 #define _GLIBCXX_PARALLEL_TAGS_H 1 35 36 #include <omp.h> 37 #include <parallel/types.h> 38 39 namespace __gnu_parallel 40 { 41 /** @brief Forces sequential execution at compile time. */ 42 struct sequential_tag { }; 43 44 /** @brief Recommends parallel execution at compile time, 45 * optionally using a user-specified number of threads. */ 46 struct parallel_tag 47 { 48 private: 49 _ThreadIndex _M_num_threads; 50 51 public: 52 /** @brief Default constructor. Use default number of threads. */ 53 parallel_tag() 54 { _M_num_threads = 0; } 55 56 /** @brief Default constructor. Recommend number of threads to use. 57 * @param __num_threads Desired number of threads. */ 58 parallel_tag(_ThreadIndex __num_threads) 59 { _M_num_threads = __num_threads; } 60 61 /** @brief Find out desired number of threads. 62 * @return Desired number of threads. */ 63 _ThreadIndex __get_num_threads() 64 { 65 if(_M_num_threads == 0) 66 return omp_get_max_threads(); 67 else 68 return _M_num_threads; 69 } 70 71 /** @brief Set the desired number of threads. 72 * @param __num_threads Desired number of threads. */ 73 void set_num_threads(_ThreadIndex __num_threads) 74 { _M_num_threads = __num_threads; } 75 }; 76 77 /** @brief Recommends parallel execution using the 78 default parallel algorithm. */ 79 struct default_parallel_tag : public parallel_tag 80 { 81 default_parallel_tag() { } 82 default_parallel_tag(_ThreadIndex __num_threads) 83 : parallel_tag(__num_threads) { } 84 }; 85 86 /** @brief Recommends parallel execution using dynamic 87 load-balancing at compile time. */ 88 struct balanced_tag : public parallel_tag { }; 89 90 /** @brief Recommends parallel execution using static 91 load-balancing at compile time. */ 92 struct unbalanced_tag : public parallel_tag { }; 93 94 /** @brief Recommends parallel execution using OpenMP dynamic 95 load-balancing at compile time. */ 96 struct omp_loop_tag : public parallel_tag { }; 97 98 /** @brief Recommends parallel execution using OpenMP static 99 load-balancing at compile time. */ 100 struct omp_loop_static_tag : public parallel_tag { }; 101 102 103 /** @brief Base class for for std::find() variants. */ 104 struct find_tag { }; 105 106 107 /** @brief Forces parallel merging 108 * with exact splitting, at compile time. */ 109 struct exact_tag : public parallel_tag 110 { 111 exact_tag() { } 112 exact_tag(_ThreadIndex __num_threads) 113 : parallel_tag(__num_threads) { } 114 }; 115 116 /** @brief Forces parallel merging 117 * with exact splitting, at compile time. */ 118 struct sampling_tag : public parallel_tag 119 { 120 sampling_tag() { } 121 sampling_tag(_ThreadIndex __num_threads) 122 : parallel_tag(__num_threads) { } 123 }; 124 125 126 /** @brief Forces parallel sorting using multiway mergesort 127 * at compile time. */ 128 struct multiway_mergesort_tag : public parallel_tag 129 { 130 multiway_mergesort_tag() { } 131 multiway_mergesort_tag(_ThreadIndex __num_threads) 132 : parallel_tag(__num_threads) { } 133 }; 134 135 /** @brief Forces parallel sorting using multiway mergesort 136 * with exact splitting at compile time. */ 137 struct multiway_mergesort_exact_tag : public parallel_tag 138 { 139 multiway_mergesort_exact_tag() { } 140 multiway_mergesort_exact_tag(_ThreadIndex __num_threads) 141 : parallel_tag(__num_threads) { } 142 }; 143 144 /** @brief Forces parallel sorting using multiway mergesort 145 * with splitting by sampling at compile time. */ 146 struct multiway_mergesort_sampling_tag : public parallel_tag 147 { 148 multiway_mergesort_sampling_tag() { } 149 multiway_mergesort_sampling_tag(_ThreadIndex __num_threads) 150 : parallel_tag(__num_threads) { } 151 }; 152 153 /** @brief Forces parallel sorting using unbalanced quicksort 154 * at compile time. */ 155 struct quicksort_tag : public parallel_tag 156 { 157 quicksort_tag() { } 158 quicksort_tag(_ThreadIndex __num_threads) 159 : parallel_tag(__num_threads) { } 160 }; 161 162 /** @brief Forces parallel sorting using balanced quicksort 163 * at compile time. */ 164 struct balanced_quicksort_tag : public parallel_tag 165 { 166 balanced_quicksort_tag() { } 167 balanced_quicksort_tag(_ThreadIndex __num_threads) 168 : parallel_tag(__num_threads) { } 169 }; 170 171 172 /** @brief Selects the growing block size variant for std::find(). 173 @see _GLIBCXX_FIND_GROWING_BLOCKS */ 174 struct growing_blocks_tag : public find_tag { }; 175 176 /** @brief Selects the constant block size variant for std::find(). 177 @see _GLIBCXX_FIND_CONSTANT_SIZE_BLOCKS */ 178 struct constant_size_blocks_tag : public find_tag { }; 179 180 /** @brief Selects the equal splitting variant for std::find(). 181 @see _GLIBCXX_FIND_EQUAL_SPLIT */ 182 struct equal_split_tag : public find_tag { }; 183 } 184 185 #endif /* _GLIBCXX_PARALLEL_TAGS_H */ 186
