3 // Copyright (C) 2007-2013 Free Software Foundation, Inc.
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
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.
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.
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/>.
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.
31 // Written by Johannes Singler and Felix Putze.
33 #ifndef _GLIBCXX_PARALLEL_TAGS_H
34 #define _GLIBCXX_PARALLEL_TAGS_H 1
37 #include <parallel/types.h>
39 namespace __gnu_parallel
41 /** @brief Forces sequential execution at compile time. */
42 struct sequential_tag
{ };
44 /** @brief Recommends parallel execution at compile time,
45 * optionally using a user-specified number of threads. */
49 _ThreadIndex _M_num_threads
;
52 /** @brief Default constructor. Use default number of threads. */
54 { _M_num_threads
= 0; }
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
; }
61 /** @brief Find out desired number of threads.
62 * @return Desired number of threads. */
63 _ThreadIndex
__get_num_threads()
65 if(_M_num_threads
== 0)
66 return omp_get_max_threads();
68 return _M_num_threads
;
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
; }
77 /** @brief Recommends parallel execution using the
78 default parallel algorithm. */
79 struct default_parallel_tag
: public parallel_tag
81 default_parallel_tag() { }
82 default_parallel_tag(_ThreadIndex __num_threads
)
83 : parallel_tag(__num_threads
) { }
86 /** @brief Recommends parallel execution using dynamic
87 load-balancing at compile time. */
88 struct balanced_tag
: public parallel_tag
{ };
90 /** @brief Recommends parallel execution using static
91 load-balancing at compile time. */
92 struct unbalanced_tag
: public parallel_tag
{ };
94 /** @brief Recommends parallel execution using OpenMP dynamic
95 load-balancing at compile time. */
96 struct omp_loop_tag
: public parallel_tag
{ };
98 /** @brief Recommends parallel execution using OpenMP static
99 load-balancing at compile time. */
100 struct omp_loop_static_tag
: public parallel_tag
{ };
103 /** @brief Base class for for std::find() variants. */
107 /** @brief Forces parallel merging
108 * with exact splitting, at compile time. */
109 struct exact_tag
: public parallel_tag
112 exact_tag(_ThreadIndex __num_threads
)
113 : parallel_tag(__num_threads
) { }
116 /** @brief Forces parallel merging
117 * with exact splitting, at compile time. */
118 struct sampling_tag
: public parallel_tag
121 sampling_tag(_ThreadIndex __num_threads
)
122 : parallel_tag(__num_threads
) { }
126 /** @brief Forces parallel sorting using multiway mergesort
127 * at compile time. */
128 struct multiway_mergesort_tag
: public parallel_tag
130 multiway_mergesort_tag() { }
131 multiway_mergesort_tag(_ThreadIndex __num_threads
)
132 : parallel_tag(__num_threads
) { }
135 /** @brief Forces parallel sorting using multiway mergesort
136 * with exact splitting at compile time. */
137 struct multiway_mergesort_exact_tag
: public parallel_tag
139 multiway_mergesort_exact_tag() { }
140 multiway_mergesort_exact_tag(_ThreadIndex __num_threads
)
141 : parallel_tag(__num_threads
) { }
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
148 multiway_mergesort_sampling_tag() { }
149 multiway_mergesort_sampling_tag(_ThreadIndex __num_threads
)
150 : parallel_tag(__num_threads
) { }
153 /** @brief Forces parallel sorting using unbalanced quicksort
154 * at compile time. */
155 struct quicksort_tag
: public parallel_tag
158 quicksort_tag(_ThreadIndex __num_threads
)
159 : parallel_tag(__num_threads
) { }
162 /** @brief Forces parallel sorting using balanced quicksort
163 * at compile time. */
164 struct balanced_quicksort_tag
: public parallel_tag
166 balanced_quicksort_tag() { }
167 balanced_quicksort_tag(_ThreadIndex __num_threads
)
168 : parallel_tag(__num_threads
) { }
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
{ };
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
{ };
180 /** @brief Selects the equal splitting variant for std::find().
181 @see _GLIBCXX_FIND_EQUAL_SPLIT */
182 struct equal_split_tag
: public find_tag
{ };
185 #endif /* _GLIBCXX_PARALLEL_TAGS_H */