tags.h
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// -*- C++ -*-
// Copyright (C) 2007-2013 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the terms
// of the GNU General Public License as published by the Free Software
// Foundation; either version 3, or (at your option) any later
// version.
// This library is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/**
* @file parallel/tags.h
* @brief Tags for compile-time selection.
* This file is a GNU parallel extension to the Standard C++ Library.
*/
// Written by Johannes Singler and Felix Putze.
#ifndef _GLIBCXX_PARALLEL_TAGS_H
#define _GLIBCXX_PARALLEL_TAGS_H 1
#include <omp.h>
#include <parallel/types.h>
namespace __gnu_parallel
{
/** @brief Forces sequential execution at compile time. */
struct sequential_tag { };
/** @brief Recommends parallel execution at compile time,
* optionally using a user-specified number of threads. */
struct parallel_tag
{
private:
_ThreadIndex _M_num_threads;
public:
/** @brief Default constructor. Use default number of threads. */
parallel_tag()
{ _M_num_threads = 0; }
/** @brief Default constructor. Recommend number of threads to use.
* @param __num_threads Desired number of threads. */
parallel_tag(_ThreadIndex __num_threads)
{ _M_num_threads = __num_threads; }
/** @brief Find out desired number of threads.
* @return Desired number of threads. */
_ThreadIndex __get_num_threads()
{
if(_M_num_threads == 0)
return omp_get_max_threads();
else
return _M_num_threads;
}
/** @brief Set the desired number of threads.
* @param __num_threads Desired number of threads. */
void set_num_threads(_ThreadIndex __num_threads)
{ _M_num_threads = __num_threads; }
};
/** @brief Recommends parallel execution using the
default parallel algorithm. */
struct default_parallel_tag : public parallel_tag
{
default_parallel_tag() { }
default_parallel_tag(_ThreadIndex __num_threads)
: parallel_tag(__num_threads) { }
};
/** @brief Recommends parallel execution using dynamic
load-balancing at compile time. */
struct balanced_tag : public parallel_tag { };
/** @brief Recommends parallel execution using static
load-balancing at compile time. */
struct unbalanced_tag : public parallel_tag { };
/** @brief Recommends parallel execution using OpenMP dynamic
load-balancing at compile time. */
struct omp_loop_tag : public parallel_tag { };
/** @brief Recommends parallel execution using OpenMP static
load-balancing at compile time. */
struct omp_loop_static_tag : public parallel_tag { };
/** @brief Base class for for std::find() variants. */
struct find_tag { };
/** @brief Forces parallel merging
* with exact splitting, at compile time. */
struct exact_tag : public parallel_tag
{
exact_tag() { }
exact_tag(_ThreadIndex __num_threads)
: parallel_tag(__num_threads) { }
};
/** @brief Forces parallel merging
* with exact splitting, at compile time. */
struct sampling_tag : public parallel_tag
{
sampling_tag() { }
sampling_tag(_ThreadIndex __num_threads)
: parallel_tag(__num_threads) { }
};
/** @brief Forces parallel sorting using multiway mergesort
* at compile time. */
struct multiway_mergesort_tag : public parallel_tag
{
multiway_mergesort_tag() { }
multiway_mergesort_tag(_ThreadIndex __num_threads)
: parallel_tag(__num_threads) { }
};
/** @brief Forces parallel sorting using multiway mergesort
* with exact splitting at compile time. */
struct multiway_mergesort_exact_tag : public parallel_tag
{
multiway_mergesort_exact_tag() { }
multiway_mergesort_exact_tag(_ThreadIndex __num_threads)
: parallel_tag(__num_threads) { }
};
/** @brief Forces parallel sorting using multiway mergesort
* with splitting by sampling at compile time. */
struct multiway_mergesort_sampling_tag : public parallel_tag
{
multiway_mergesort_sampling_tag() { }
multiway_mergesort_sampling_tag(_ThreadIndex __num_threads)
: parallel_tag(__num_threads) { }
};
/** @brief Forces parallel sorting using unbalanced quicksort
* at compile time. */
struct quicksort_tag : public parallel_tag
{
quicksort_tag() { }
quicksort_tag(_ThreadIndex __num_threads)
: parallel_tag(__num_threads) { }
};
/** @brief Forces parallel sorting using balanced quicksort
* at compile time. */
struct balanced_quicksort_tag : public parallel_tag
{
balanced_quicksort_tag() { }
balanced_quicksort_tag(_ThreadIndex __num_threads)
: parallel_tag(__num_threads) { }
};
/** @brief Selects the growing block size variant for std::find().
@see _GLIBCXX_FIND_GROWING_BLOCKS */
struct growing_blocks_tag : public find_tag { };
/** @brief Selects the constant block size variant for std::find().
@see _GLIBCXX_FIND_CONSTANT_SIZE_BLOCKS */
struct constant_size_blocks_tag : public find_tag { };
/** @brief Selects the equal splitting variant for std::find().
@see _GLIBCXX_FIND_EQUAL_SPLIT */
struct equal_split_tag : public find_tag { };
}
#endif /* _GLIBCXX_PARALLEL_TAGS_H */