libstdc++
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 
43 namespace __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)
73  (__begin, __end, __user_op, __functionality, __reduction,
74  __reduction_start, __output, __bound);
75  else if (__parallelism_tag == parallel_omp_loop)
77  (__begin, __end, __user_op, __functionality, __reduction,
78  __reduction_start, __output, __bound);
79  else if (__parallelism_tag == parallel_omp_loop_static)
81  (__begin, __end, __user_op, __functionality, __reduction,
82  __reduction_start, __output, __bound);
83  else //e. g. parallel_balanced
85  (__begin, __end, __user_op, __functionality, __reduction,
86  __reduction_start, __output, __bound);
87  }
88 }
89 
90 #endif /* _GLIBCXX_PARALLEL_FOR_EACH_H */
Parallelization of embarrassingly parallel execution by means of work-stealing.
Parallelization of embarrassingly parallel execution by means of an OpenMP for loop. This file is a GNU parallel extension to the Standard C++ Library.
_Parallelism
Run-time equivalents for the compile-time tags.
Definition: types.h:44
Parallelization of embarrassingly parallel execution by means of equal splitting. This file is a GNU ...
Parallel with OpenMP static load-balancing.
Definition: types.h:59
Runtime settings and tuning parameters, heuristics to decide whether to use parallelized algorithms...
_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
_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
_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
Parallel with OpenMP dynamic load-balancing.
Definition: types.h:56
GNU parallel code for public use.
_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
Parallel unbalanced (equal-sized chunks).
Definition: types.h:50