libstdc++
for_each.h
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1 // -*- C++ -*-
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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 "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 InputIterator, typename UserOp,
59  typename Functionality, typename Red, typename Result>
60  UserOp
61  for_each_template_random_access(InputIterator begin, InputIterator end,
62  UserOp user_op,
63  Functionality& functionality,
64  Red reduction, Result reduction_start,
65  Result& output, typename
67  difference_type bound,
68  _Parallelism parallelism_tag)
69  {
70  if (parallelism_tag == parallel_unbalanced)
71  return for_each_template_random_access_ed(begin, end, user_op,
72  functionality, reduction,
73  reduction_start,
74  output, bound);
75  else if (parallelism_tag == parallel_omp_loop)
76  return for_each_template_random_access_omp_loop(begin, end, user_op,
77  functionality,
78  reduction,
79  reduction_start,
80  output, bound);
81  else if (parallelism_tag == parallel_omp_loop_static)
82  return for_each_template_random_access_omp_loop(begin, end, user_op,
83  functionality,
84  reduction,
85  reduction_start,
86  output, bound);
87  else //e. g. parallel_balanced
89  user_op,
90  functionality,
91  reduction,
92  reduction_start,
93  output, bound);
94  }
95 }
96 
97 #endif /* _GLIBCXX_PARALLEL_FOR_EACH_H */