for_each.h
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// -*- C++ -*-
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//
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/** @file parallel/for_each.h
* @brief Main interface for embarrassingly parallel functions.
*
* The explicit implementation are in other header files, like
* workstealing.h, par_loop.h, omp_loop.h, and omp_loop_static.h.
* This file is a GNU parallel extension to the Standard C++ Library.
*/
// Written by Felix Putze.
#ifndef _GLIBCXX_PARALLEL_FOR_EACH_H
#define _GLIBCXX_PARALLEL_FOR_EACH_H 1
#include <parallel/settings.h>
#include <parallel/par_loop.h>
#include <parallel/omp_loop.h>
#include <parallel/workstealing.h>
namespace __gnu_parallel
{
/** @brief Chose the desired algorithm by evaluating @c __parallelism_tag.
* @param __begin Begin iterator of input sequence.
* @param __end End iterator of input sequence.
* @param __user_op A user-specified functor (comparator, predicate,
* associative operator,...)
* @param __functionality functor to @a process an element with
* __user_op (depends on desired functionality, e. g. accumulate,
* for_each,...
* @param __reduction Reduction functor.
* @param __reduction_start Initial value for reduction.
* @param __output Output iterator.
* @param __bound Maximum number of elements processed.
* @param __parallelism_tag Parallelization method */
template<typename _IIter, typename _UserOp,
typename _Functionality, typename _Red, typename _Result>
_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)
{
if (__parallelism_tag == parallel_unbalanced)
return __for_each_template_random_access_ed
(__begin, __end, __user_op, __functionality, __reduction,
__reduction_start, __output, __bound);
else if (__parallelism_tag == parallel_omp_loop)
return __for_each_template_random_access_omp_loop
(__begin, __end, __user_op, __functionality, __reduction,
__reduction_start, __output, __bound);
else if (__parallelism_tag == parallel_omp_loop_static)
return __for_each_template_random_access_omp_loop
(__begin, __end, __user_op, __functionality, __reduction,
__reduction_start, __output, __bound);
else //e. g. parallel_balanced
return __for_each_template_random_access_workstealing
(__begin, __end, __user_op, __functionality, __reduction,
__reduction_start, __output, __bound);
}
}
#endif /* _GLIBCXX_PARALLEL_FOR_EACH_H */
par_loop.h
Parallelization of embarrassingly parallel execution by means of equal splitting. This file is a GNU ...
omp_loop.h
Parallelization of embarrassingly parallel execution by means of an OpenMP for loop....
workstealing.h
Parallelization of embarrassingly parallel execution by means of work-stealing.
settings.h
Runtime settings and tuning parameters, heuristics to decide whether to use parallelized algorithms.
__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