libstdc++: for_each.h Source File

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for_each.h
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24
25/** @file parallel/for_each.h
26 * @brief Main interface for embarrassingly parallel functions.
27 *
28 * The explicit implementation are in other header files, like
29 * workstealing.h, par_loop.h, omp_loop.h, and omp_loop_static.h.
30 * This file is a GNU parallel extension to the Standard C++ Library.
31 */
32
33// Written by Felix Putze.
34
35#ifndef _GLIBCXX_PARALLEL_FOR_EACH_H
36#define _GLIBCXX_PARALLEL_FOR_EACH_H 1
37
38#include <parallel/settings.h>
39#include <parallel/par_loop.h>
40#include <parallel/omp_loop.h>
41#include <parallel/workstealing.h>
42
43namespace __gnu_parallel
44{
45 /** @brief Chose the desired algorithm by evaluating @c __parallelism_tag.
46 * @param __begin Begin iterator of input sequence.
47 * @param __end End iterator of input sequence.
48 * @param __user_op A user-specified functor (comparator, predicate,
49 * associative operator,...)
50 * @param __functionality functor to @a process an element with
51 * __user_op (depends on desired functionality, e. g. accumulate,
52 * for_each,...
53 * @param __reduction Reduction functor.
54 * @param __reduction_start Initial value for reduction.
55 * @param __output Output iterator.
56 * @param __bound Maximum number of elements processed.
57 * @param __parallelism_tag Parallelization method */
58 template<typename _IIter, typename _UserOp,
59 typename _Functionality, typename _Red, typename _Result>
60 _UserOp
61 __for_each_template_random_access(_IIter __begin, _IIter __end,
62 _UserOp __user_op,
63 _Functionality& __functionality,
64 _Red __reduction,
65 _Result __reduction_start,
66 _Result& __output, typename
67 std::iterator_traits<_IIter>::
68 difference_type __bound,
69 _Parallelism __parallelism_tag)
70 {
71 if (__parallelism_tag == parallel_unbalanced)
72 return __for_each_template_random_access_ed
73 (__begin, __end, __user_op, __functionality, __reduction,
74 __reduction_start, __output, __bound);
75 else if (__parallelism_tag == parallel_omp_loop)
76 return __for_each_template_random_access_omp_loop
77 (__begin, __end, __user_op, __functionality, __reduction,
78 __reduction_start, __output, __bound);
79 else if (__parallelism_tag == parallel_omp_loop_static)
80 return __for_each_template_random_access_omp_loop
81 (__begin, __end, __user_op, __functionality, __reduction,
82 __reduction_start, __output, __bound);
83 else //e. g. parallel_balanced
84 return __for_each_template_random_access_workstealing
85 (__begin, __end, __user_op, __functionality, __reduction,
86 __reduction_start, __output, __bound);
87 }
88}
89
90#endif /* _GLIBCXX_PARALLEL_FOR_EACH_H */
omp_loop.h
Parallelization of embarrassingly parallel execution by means of an OpenMP for loop....
par_loop.h
Parallelization of embarrassingly parallel execution by means of equal splitting. This file is a GNU ...
settings.h
Runtime settings and tuning parameters, heuristics to decide whether to use parallelized algorithms.
workstealing.h
Parallelization of embarrassingly parallel execution by means of work-stealing.
__gnu_parallel
GNU parallel code for public use.
Definition balanced_quicksort.h:62
__gnu_parallel::__for_each_template_random_access
_UserOp __for_each_template_random_access(_IIter __begin, _IIter __end, _UserOp __user_op, _Functionality &__functionality, _Red __reduction, _Result __reduction_start, _Result &__output, typename std::iterator_traits< _IIter >::difference_type __bound, _Parallelism __parallelism_tag)
Chose the desired algorithm by evaluating __parallelism_tag.
Definition for_each.h:61
__gnu_parallel::__for_each_template_random_access_ed
_Op __for_each_template_random_access_ed(_RAIter __begin, _RAIter __end, _Op __o, _Fu &__f, _Red __r, _Result __base, _Result &__output, typename std::iterator_traits< _RAIter >::difference_type __bound)
Embarrassingly parallel algorithm for random access iterators, using hand-crafted parallelization by ...
Definition par_loop.h:67
__gnu_parallel::__for_each_template_random_access_workstealing
_Op __for_each_template_random_access_workstealing(_RAIter __begin, _RAIter __end, _Op __op, _Fu &__f, _Red __r, _Result __base, _Result &__output, typename std::iterator_traits< _RAIter >::difference_type __bound)
Work stealing algorithm for random access iterators.
Definition workstealing.h:99
__gnu_parallel::__for_each_template_random_access_omp_loop
_Op __for_each_template_random_access_omp_loop(_RAIter __begin, _RAIter __end, _Op __o, _Fu &__f, _Red __r, _Result __base, _Result &__output, typename std::iterator_traits< _RAIter >::difference_type __bound)
Embarrassingly parallel algorithm for random access iterators, using an OpenMP for loop.
Definition omp_loop.h:67
__gnu_parallel::_Parallelism
_Parallelism
Run-time equivalents for the compile-time tags.
Definition types.h:45
__gnu_parallel::parallel_omp_loop_static
@ parallel_omp_loop_static
Parallel with OpenMP static load-balancing.
Definition types.h:59
__gnu_parallel::parallel_unbalanced
@ parallel_unbalanced
Parallel unbalanced (equal-sized chunks).
Definition types.h:50
__gnu_parallel::parallel_omp_loop
@ parallel_omp_loop
Parallel with OpenMP dynamic load-balancing.
Definition types.h:56
std::iterator_traits
Traits class for iterators.
Definition stl_iterator_base_types.h:180