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📄 algo.h // -- C++ -- // Copyright (C) 2007-2021 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/algo.h * @brief Parallel STL function calls corresponding to the stl_algo.h header. * * The functions defined here mainly do case switches and * call the actual parallelized versions in other files. * Inlining policy: Functions that basically only contain one function call, * are declared inline. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler and Felix Putze. #ifndef _GLIBCXX_PARALLEL_ALGO_H #define _GLIBCXX_PARALLEL_ALGO_H 1 #include <parallel/algorithmfwd.h> #include <bits/stl_algobase.h> #include <bits/stl_algo.h> #include <parallel/iterator.h> #include <parallel/base.h> #include <parallel/sort.h> #include <parallel/workstealing.h> #include <parallel/par_loop.h> #include <parallel/omp_loop.h> #include <parallel/omp_loop_static.h> #include <parallel/for_each_selectors.h> #include <parallel/for_each.h> #include <parallel/find.h> #include <parallel/find_selectors.h> #include <parallel/search.h> #include <parallel/random_shuffle.h> #include <parallel/partition.h> #include <parallel/merge.h> #include <parallel/unique_copy.h> #include <parallel/set_operations.h> namespace std _GLIBCXX_VISIBILITY(default) { namespace __parallel { // Sequential fallback template<typename _IIter, typename _Function> inline _Function for_each(_IIter __begin, _IIter __end, _Function __f, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::for_each(__begin, __end, __f); } // Sequential fallback for input iterator case template<typename _IIter, typename _Function, typename _IteratorTag> inline _Function __for_each_switch(_IIter __begin, _IIter __end, _Function __f, _IteratorTag) { return for_each(__begin, __end, __f, __gnu_parallel::sequential_tag()); } // Parallel algorithm for random access iterators template<typename _RAIter, typename _Function> _Function __for_each_switch(_RAIter __begin, _RAIter __end, _Function __f, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().for_each_minimal_n && __gnu_parallel::__is_parallel(__parallelism_tag))) { bool __dummy; __gnu_parallel::__for_each_selector<_RAIter> __functionality; return __gnu_parallel:: __for_each_template_random_access( __begin, __end, __f, __functionality, __gnu_parallel::_DummyReduct(), true, __dummy, -1, __parallelism_tag); } else return for_each(__begin, __end, __f, __gnu_parallel::sequential_tag()); } // Public interface template<typename _Iterator, typename _Function> inline _Function for_each(_Iterator __begin, _Iterator __end, _Function __f, __gnu_parallel::_Parallelism __parallelism_tag) { return __for_each_switch(__begin, __end, __f, std::__iterator_category(__begin), __parallelism_tag); } template<typename _Iterator, typename _Function> inline _Function for_each(_Iterator __begin, _Iterator __end, _Function __f) { return __for_each_switch(__begin, __end, __f, std::__iterator_category(__begin)); } // Sequential fallback template<typename _IIter, typename _Tp> inline _IIter find(_IIter __begin, _IIter __end, const _Tp& __val, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::find(__begin, __end, __val); } // Sequential fallback for input iterator case template<typename _IIter, typename _Tp, typename _IteratorTag> inline _IIter __find_switch(_IIter __begin, _IIter __end, const _Tp& __val, _IteratorTag) { return _GLIBCXX_STD_A::find(__begin, __end, __val); } // Parallel find for random access iterators template<typename _RAIter, typename _Tp> _RAIter __find_switch(_RAIter __begin, _RAIter __end, const _Tp& __val, random_access_iterator_tag) { typedef iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; if (_GLIBCXX_PARALLEL_CONDITION(true)) { __gnu_parallel::__binder2nd<__gnu_parallel::_EqualTo<_ValueType, const _Tp&>, _ValueType, const _Tp&, bool> __comp(__gnu_parallel::_EqualTo<_ValueType, const _Tp&>(), __val); return __gnu_parallel::__find_template( __begin, __end, __begin, __comp, __gnu_parallel::__find_if_selector()).first; } else return _GLIBCXX_STD_A::find(__begin, __end, __val); } // Public interface template<typename _IIter, typename _Tp> inline _IIter find(_IIter __begin, _IIter __end, const _Tp& __val) { return __find_switch(__begin, __end, __val, std::__iterator_category(__begin)); } // Sequential fallback template<typename _IIter, typename _Predicate> inline _IIter find_if(_IIter __begin, _IIter __end, _Predicate __pred, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::find_if(__begin, __end, __pred); } // Sequential fallback for input iterator case template<typename _IIter, typename _Predicate, typename _IteratorTag> inline _IIter __find_if_switch(_IIter __begin, _IIter __end, _Predicate __pred, _IteratorTag) { return _GLIBCXX_STD_A::find_if(__begin, __end, __pred); } // Parallel find_if for random access iterators template<typename _RAIter, typename _Predicate> _RAIter __find_if_switch(_RAIter __begin, _RAIter __end, _Predicate __pred, random_access_iterator_tag) { if (_GLIBCXX_PARALLEL_CONDITION(true)) return __gnu_parallel::__find_template(__begin, __end, __begin, __pred, __gnu_parallel:: __find_if_selector()).first; else return _GLIBCXX_STD_A::find_if(__begin, __end, __pred); } // Public interface template<typename _IIter, typename _Predicate> inline _IIter find_if(_IIter __begin, _IIter __end, _Predicate __pred) { return __find_if_switch(__begin, __end, __pred, std::__iterator_category(__begin)); } // Sequential fallback template<typename _IIter, typename _FIterator> inline _IIter find_first_of(_IIter __begin1, _IIter __end1, _FIterator __begin2, _FIterator __end2, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::find_first_of(__begin1, __end1, __begin2, __end2); } // Sequential fallback template<typename _IIter, typename _FIterator, typename _BinaryPredicate> inline _IIter find_first_of(_IIter __begin1, _IIter __end1, _FIterator __begin2, _FIterator __end2, _BinaryPredicate __comp, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::find_first_of( __begin1, __end1, __begin2, __end2, __comp); } // Sequential fallback for input iterator type template<typename _IIter, typename _FIterator, typename _IteratorTag1, typename _IteratorTag2> inline _IIter __find_first_of_switch(_IIter __begin1, _IIter __end1, _FIterator __begin2, _FIterator __end2, _IteratorTag1, _IteratorTag2) { return find_first_of(__begin1, __end1, __begin2, __end2, __gnu_parallel::sequential_tag()); } // Parallel algorithm for random access iterators template<typename _RAIter, typename _FIterator, typename _BinaryPredicate, typename _IteratorTag> inline _RAIter __find_first_of_switch(_RAIter __begin1, _RAIter __end1, _FIterator __begin2, _FIterator __end2, _BinaryPredicate __comp, random_access_iterator_tag, _IteratorTag) { return __gnu_parallel:: __find_template(__begin1, __end1, __begin1, __comp, __gnu_parallel::__find_first_of_selector <_FIterator>(__begin2, __end2)).first; } // Sequential fallback for input iterator type template<typename _IIter, typename _FIterator, typename _BinaryPredicate, typename _IteratorTag1, typename _IteratorTag2> inline _IIter __find_first_of_switch(_IIter __begin1, _IIter __end1, _FIterator __begin2, _FIterator __end2, _BinaryPredicate __comp, _IteratorTag1, _IteratorTag2) { return find_first_of(__begin1, __end1, __begin2, __end2, __comp, __gnu_parallel::sequential_tag()); } // Public interface template<typename _IIter, typename _FIterator, typename _BinaryPredicate> inline _IIter find_first_of(_IIter __begin1, _IIter __end1, _FIterator __begin2, _FIterator __end2, _BinaryPredicate __comp) { return __find_first_of_switch(__begin1, __end1, __begin2, __end2, __comp, std::__iterator_category(__begin1), std::__iterator_category(__begin2)); } // Public interface, insert default comparator template<typename _IIter, typename _FIterator> inline _IIter find_first_of(_IIter __begin1, _IIter __end1, _FIterator __begin2, _FIterator __end2) { typedef typename std::iterator_traits<_IIter>::value_type _IValueType; typedef typename std::iterator_traits<_FIterator>::value_type _FValueType; return __gnu_parallel::find_first_of(__begin1, __end1, __begin2, __end2, __gnu_parallel::_EqualTo<_IValueType, _FValueType>()); } // Sequential fallback template<typename _IIter, typename _OutputIterator> inline _OutputIterator unique_copy(_IIter __begin1, _IIter __end1, _OutputIterator __out, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::unique_copy(__begin1, __end1, __out); } // Sequential fallback template<typename _IIter, typename _OutputIterator, typename _Predicate> inline _OutputIterator unique_copy(_IIter __begin1, _IIter __end1, _OutputIterator __out, _Predicate __pred, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::unique_copy(__begin1, __end1, __out, __pred); } // Sequential fallback for input iterator case template<typename _IIter, typename _OutputIterator, typename _Predicate, typename _IteratorTag1, typename _IteratorTag2> inline _OutputIterator __unique_copy_switch(_IIter __begin, _IIter __last, _OutputIterator __out, _Predicate __pred, _IteratorTag1, _IteratorTag2) { return _GLIBCXX_STD_A::unique_copy(__begin, __last, __out, __pred); } // Parallel unique_copy for random access iterators template<typename _RAIter, typename _RandomAccessOutputIterator, typename _Predicate> _RandomAccessOutputIterator __unique_copy_switch(_RAIter __begin, _RAIter __last, _RandomAccessOutputIterator __out, _Predicate __pred, random_access_iterator_tag, random_access_iterator_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__last - __begin) > __gnu_parallel::_Settings::get().unique_copy_minimal_n)) return __gnu_parallel::__parallel_unique_copy( __begin, __last, __out, __pred); else return _GLIBCXX_STD_A::unique_copy(__begin, __last, __out, __pred); } // Public interface template<typename _IIter, typename _OutputIterator> inline _OutputIterator unique_copy(_IIter __begin1, _IIter __end1, _OutputIterator __out) { typedef typename std::iterator_traits<_IIter>::value_type _ValueType; return __unique_copy_switch( __begin1, __end1, __out, equal_to<_ValueType>(), std::__iterator_category(__begin1), std::__iterator_category(__out)); } // Public interface template<typename _IIter, typename _OutputIterator, typename _Predicate> inline _OutputIterator unique_copy(_IIter __begin1, _IIter __end1, _OutputIterator __out, _Predicate __pred) { return __unique_copy_switch( __begin1, __end1, __out, __pred, std::__iterator_category(__begin1), std::__iterator_category(__out)); } // Sequential fallback template<typename _IIter1, typename _IIter2, typename _OutputIterator> inline _OutputIterator set_union(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __out, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::set_union( __begin1, __end1, __begin2, __end2, __out); } // Sequential fallback template<typename _IIter1, typename _IIter2, typename _OutputIterator, typename _Predicate> inline _OutputIterator set_union(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __out, _Predicate __pred, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::set_union(__begin1, __end1, __begin2, __end2, __out, __pred); } // Sequential fallback for input iterator case template<typename _IIter1, typename _IIter2, typename _Predicate, typename _OutputIterator, typename _IteratorTag1, typename _IteratorTag2, typename _IteratorTag3> inline _OutputIterator __set_union_switch( _IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __result, _Predicate __pred, _IteratorTag1, _IteratorTag2, _IteratorTag3) { return _GLIBCXX_STD_A::set_union(__begin1, __end1, __begin2, __end2, __result, __pred); } // Parallel set_union for random access iterators template<typename _RAIter1, typename _RAIter2, typename _Output_RAIter, typename _Predicate> _Output_RAIter __set_union_switch(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _RAIter2 __end2, _Output_RAIter __result, _Predicate __pred, random_access_iterator_tag, random_access_iterator_tag, random_access_iterator_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end1 - __begin1) >= __gnu_parallel::_Settings::get().set_union_minimal_n \|\| static_cast<__gnu_parallel::_SequenceIndex>(__end2 - __begin2) >= __gnu_parallel::_Settings::get().set_union_minimal_n)) return __gnu_parallel::__parallel_set_union( __begin1, __end1, __begin2, __end2, __result, __pred); else return _GLIBCXX_STD_A::set_union(__begin1, __end1, __begin2, __end2, __result, __pred); } // Public interface template<typename _IIter1, typename _IIter2, typename _OutputIterator> inline _OutputIterator set_union(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __out) { typedef typename std::iterator_traits<_IIter1>::value_type _ValueType1; typedef typename std::iterator_traits<_IIter2>::value_type _ValueType2; return __set_union_switch( __begin1, __end1, __begin2, __end2, __out, __gnu_parallel::_Less<_ValueType1, _ValueType2>(), std::__iterator_category(__begin1), std::__iterator_category(__begin2), std::__iterator_category(__out)); } // Public interface template<typename _IIter1, typename _IIter2, typename _OutputIterator, typename _Predicate> inline _OutputIterator set_union(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __out, _Predicate __pred) { return __set_union_switch( __begin1, __end1, __begin2, __end2, __out, __pred, std::__iterator_category(__begin1), std::__iterator_category(__begin2), std::__iterator_category(__out)); } // Sequential fallback. template<typename _IIter1, typename _IIter2, typename _OutputIterator> inline _OutputIterator set_intersection(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __out, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::set_intersection(__begin1, __end1, __begin2, __end2, __out); } // Sequential fallback. template<typename _IIter1, typename _IIter2, typename _OutputIterator, typename _Predicate> inline _OutputIterator set_intersection(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __out, _Predicate __pred, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::set_intersection( __begin1, __end1, __begin2, __end2, __out, __pred); } // Sequential fallback for input iterator case template<typename _IIter1, typename _IIter2, typename _Predicate, typename _OutputIterator, typename _IteratorTag1, typename _IteratorTag2, typename _IteratorTag3> inline _OutputIterator __set_intersection_switch(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __result, _Predicate __pred, _IteratorTag1, _IteratorTag2, _IteratorTag3) { return _GLIBCXX_STD_A::set_intersection(__begin1, __end1, __begin2, __end2, __result, __pred); } // Parallel set_intersection for random access iterators template<typename _RAIter1, typename _RAIter2, typename _Output_RAIter, typename _Predicate> _Output_RAIter __set_intersection_switch(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _RAIter2 __end2, _Output_RAIter __result, _Predicate __pred, random_access_iterator_tag, random_access_iterator_tag, random_access_iterator_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end1 - __begin1) >= __gnu_parallel::_Settings::get().set_union_minimal_n \|\| static_cast<__gnu_parallel::_SequenceIndex>(__end2 - __begin2) >= __gnu_parallel::_Settings::get().set_union_minimal_n)) return __gnu_parallel::__parallel_set_intersection( __begin1, __end1, __begin2, __end2, __result, __pred); else return _GLIBCXX_STD_A::set_intersection( __begin1, __end1, __begin2, __end2, __result, __pred); } // Public interface template<typename _IIter1, typename _IIter2, typename _OutputIterator> inline _OutputIterator set_intersection(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __out) { typedef typename std::iterator_traits<_IIter1>::value_type _ValueType1; typedef typename std::iterator_traits<_IIter2>::value_type _ValueType2; return __set_intersection_switch( __begin1, __end1, __begin2, __end2, __out, __gnu_parallel::_Less<_ValueType1, _ValueType2>(), std::__iterator_category(__begin1), std::__iterator_category(__begin2), std::__iterator_category(__out)); } template<typename _IIter1, typename _IIter2, typename _OutputIterator, typename _Predicate> inline _OutputIterator set_intersection(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __out, _Predicate __pred) { return __set_intersection_switch( __begin1, __end1, __begin2, __end2, __out, __pred, std::__iterator_category(__begin1), std::__iterator_category(__begin2), std::__iterator_category(__out)); } // Sequential fallback template<typename _IIter1, typename _IIter2, typename _OutputIterator> inline _OutputIterator set_symmetric_difference(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __out, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::set_symmetric_difference( __begin1, __end1, __begin2, __end2, __out); } // Sequential fallback template<typename _IIter1, typename _IIter2, typename _OutputIterator, typename _Predicate> inline _OutputIterator set_symmetric_difference(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __out, _Predicate __pred, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::set_symmetric_difference( __begin1, __end1, __begin2, __end2, __out, __pred); } // Sequential fallback for input iterator case template<typename _IIter1, typename _IIter2, typename _Predicate, typename _OutputIterator, typename _IteratorTag1, typename _IteratorTag2, typename _IteratorTag3> inline _OutputIterator __set_symmetric_difference_switch( _IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __result, _Predicate __pred, _IteratorTag1, _IteratorTag2, _IteratorTag3) { return _GLIBCXX_STD_A::set_symmetric_difference( __begin1, __end1, __begin2, __end2, __result, __pred); } // Parallel set_symmetric_difference for random access iterators template<typename _RAIter1, typename _RAIter2, typename _Output_RAIter, typename _Predicate> _Output_RAIter __set_symmetric_difference_switch(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _RAIter2 __end2, _Output_RAIter __result, _Predicate __pred, random_access_iterator_tag, random_access_iterator_tag, random_access_iterator_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end1 - __begin1) >= __gnu_parallel::_Settings::get().set_symmetric_difference_minimal_n \|\| static_cast<__gnu_parallel::_SequenceIndex>(__end2 - __begin2) >= __gnu_parallel::_Settings::get().set_symmetric_difference_minimal_n)) return __gnu_parallel::__parallel_set_symmetric_difference( __begin1, __end1, __begin2, __end2, __result, __pred); else return _GLIBCXX_STD_A::set_symmetric_difference( __begin1, __end1, __begin2, __end2, __result, __pred); } // Public interface. template<typename _IIter1, typename _IIter2, typename _OutputIterator> inline _OutputIterator set_symmetric_difference(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __out) { typedef typename std::iterator_traits<_IIter1>::value_type _ValueType1; typedef typename std::iterator_traits<_IIter2>::value_type _ValueType2; return __set_symmetric_difference_switch( __begin1, __end1, __begin2, __end2, __out, __gnu_parallel::_Less<_ValueType1, _ValueType2>(), std::__iterator_category(__begin1), std::__iterator_category(__begin2), std::__iterator_category(__out)); } // Public interface. template<typename _IIter1, typename _IIter2, typename _OutputIterator, typename _Predicate> inline _OutputIterator set_symmetric_difference(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __out, _Predicate __pred) { return __set_symmetric_difference_switch( __begin1, __end1, __begin2, __end2, __out, __pred, std::__iterator_category(__begin1), std::__iterator_category(__begin2), std::__iterator_category(__out)); } // Sequential fallback. template<typename _IIter1, typename _IIter2, typename _OutputIterator> inline _OutputIterator set_difference(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __out, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::set_difference( __begin1,__end1, __begin2, __end2, __out); } // Sequential fallback. template<typename _IIter1, typename _IIter2, typename _OutputIterator, typename _Predicate> inline _OutputIterator set_difference(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __out, _Predicate __pred, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::set_difference(__begin1, __end1, __begin2, __end2, __out, __pred); } // Sequential fallback for input iterator case. template<typename _IIter1, typename _IIter2, typename _Predicate, typename _OutputIterator, typename _IteratorTag1, typename _IteratorTag2, typename _IteratorTag3> inline _OutputIterator __set_difference_switch(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __result, _Predicate __pred, _IteratorTag1, _IteratorTag2, _IteratorTag3) { return _GLIBCXX_STD_A::set_difference( __begin1, __end1, __begin2, __end2, __result, __pred); } // Parallel set_difference for random access iterators template<typename _RAIter1, typename _RAIter2, typename _Output_RAIter, typename _Predicate> _Output_RAIter __set_difference_switch(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _RAIter2 __end2, _Output_RAIter __result, _Predicate __pred, random_access_iterator_tag, random_access_iterator_tag, random_access_iterator_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end1 - __begin1) >= __gnu_parallel::_Settings::get().set_difference_minimal_n \|\| static_cast<__gnu_parallel::_SequenceIndex>(__end2 - __begin2) >= __gnu_parallel::_Settings::get().set_difference_minimal_n)) return __gnu_parallel::__parallel_set_difference( __begin1, __end1, __begin2, __end2, __result, __pred); else return _GLIBCXX_STD_A::set_difference( __begin1, __end1, __begin2, __end2, __result, __pred); } // Public interface template<typename _IIter1, typename _IIter2, typename _OutputIterator> inline _OutputIterator set_difference(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __out) { typedef typename std::iterator_traits<_IIter1>::value_type _ValueType1; typedef typename std::iterator_traits<_IIter2>::value_type _ValueType2; return __set_difference_switch( __begin1, __end1, __begin2, __end2, __out, __gnu_parallel::_Less<_ValueType1, _ValueType2>(), std::__iterator_category(__begin1), std::__iterator_category(__begin2), std::__iterator_category(__out)); } // Public interface template<typename _IIter1, typename _IIter2, typename _OutputIterator, typename _Predicate> inline _OutputIterator set_difference(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __out, _Predicate __pred) { return __set_difference_switch( __begin1, __end1, __begin2, __end2, __out, __pred, std::__iterator_category(__begin1), std::__iterator_category(__begin2), std::__iterator_category(__out)); } // Sequential fallback template<typename _FIterator> inline _FIterator adjacent_find(_FIterator __begin, _FIterator __end, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::adjacent_find(__begin, __end); } // Sequential fallback template<typename _FIterator, typename _BinaryPredicate> inline _FIterator adjacent_find(_FIterator __begin, _FIterator __end, _BinaryPredicate __binary_pred, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::adjacent_find(__begin, __end, __binary_pred); } // Parallel algorithm for random access iterators template<typename _RAIter> _RAIter __adjacent_find_switch(_RAIter __begin, _RAIter __end, random_access_iterator_tag) { typedef iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; if (_GLIBCXX_PARALLEL_CONDITION(true)) { _RAIter __spot = __gnu_parallel:: __find_template( __begin, __end - 1, __begin, equal_to<_ValueType>(), __gnu_parallel::__adjacent_find_selector()) .first; if (__spot == (__end - 1)) return __end; else return __spot; } else return adjacent_find(__begin, __end, __gnu_parallel::sequential_tag()); } // Sequential fallback for input iterator case template<typename _FIterator, typename _IteratorTag> inline _FIterator __adjacent_find_switch(_FIterator __begin, _FIterator __end, _IteratorTag) { return adjacent_find(__begin, __end, __gnu_parallel::sequential_tag()); } // Public interface template<typename _FIterator> inline _FIterator adjacent_find(_FIterator __begin, _FIterator __end) { return __adjacent_find_switch(__begin, __end, std::__iterator_category(__begin)); } // Sequential fallback for input iterator case template<typename _FIterator, typename _BinaryPredicate, typename _IteratorTag> inline _FIterator __adjacent_find_switch(_FIterator __begin, _FIterator __end, _BinaryPredicate __pred, _IteratorTag) { return adjacent_find(__begin, __end, __pred, __gnu_parallel::sequential_tag()); } // Parallel algorithm for random access iterators template<typename _RAIter, typename _BinaryPredicate> _RAIter __adjacent_find_switch(_RAIter __begin, _RAIter __end, _BinaryPredicate __pred, random_access_iterator_tag) { if (_GLIBCXX_PARALLEL_CONDITION(true)) return __gnu_parallel::__find_template(__begin, __end, __begin, __pred, __gnu_parallel:: __adjacent_find_selector()).first; else return adjacent_find(__begin, __end, __pred, __gnu_parallel::sequential_tag()); } // Public interface template<typename _FIterator, typename _BinaryPredicate> inline _FIterator adjacent_find(_FIterator __begin, _FIterator __end, _BinaryPredicate __pred) { return __adjacent_find_switch(__begin, __end, __pred, std::__iterator_category(__begin)); } // Sequential fallback template<typename _IIter, typename _Tp> inline typename iterator_traits<_IIter>::difference_type count(_IIter __begin, _IIter __end, const _Tp& __value, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::count(__begin, __end, __value); } // Parallel code for random access iterators template<typename _RAIter, typename _Tp> typename iterator_traits<_RAIter>::difference_type __count_switch(_RAIter __begin, _RAIter __end, const _Tp& __value, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism_tag) { typedef iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; typedef __gnu_parallel::_SequenceIndex _SequenceIndex; if (_GLIBCXX_PARALLEL_CONDITION( static_cast<_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().count_minimal_n && __gnu_parallel::__is_parallel(__parallelism_tag))) { __gnu_parallel::__count_selector<_RAIter, _DifferenceType> __functionality; _DifferenceType __res = 0; __gnu_parallel:: __for_each_template_random_access( __begin, __end, __value, __functionality, std::plus<_SequenceIndex>(), __res, __res, -1, __parallelism_tag); return __res; } else return count(__begin, __end, __value, __gnu_parallel::sequential_tag()); } // Sequential fallback for input iterator case. template<typename _IIter, typename _Tp, typename _IteratorTag> inline typename iterator_traits<_IIter>::difference_type __count_switch(_IIter __begin, _IIter __end, const _Tp& __value, _IteratorTag) { return count(__begin, __end, __value, __gnu_parallel::sequential_tag()); } // Public interface. template<typename _IIter, typename _Tp> inline typename iterator_traits<_IIter>::difference_type count(_IIter __begin, _IIter __end, const _Tp& __value, __gnu_parallel::_Parallelism __parallelism_tag) { return __count_switch(__begin, __end, __value, std::__iterator_category(__begin), __parallelism_tag); } template<typename _IIter, typename _Tp> inline typename iterator_traits<_IIter>::difference_type count(_IIter __begin, _IIter __end, const _Tp& __value) { return __count_switch(__begin, __end, __value, std::__iterator_category(__begin)); } // Sequential fallback. template<typename _IIter, typename _Predicate> inline typename iterator_traits<_IIter>::difference_type count_if(_IIter __begin, _IIter __end, _Predicate __pred, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::count_if(__begin, __end, __pred); } // Parallel count_if for random access iterators template<typename _RAIter, typename _Predicate> typename iterator_traits<_RAIter>::difference_type __count_if_switch(_RAIter __begin, _RAIter __end, _Predicate __pred, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism_tag) { typedef iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; typedef __gnu_parallel::_SequenceIndex _SequenceIndex; if (_GLIBCXX_PARALLEL_CONDITION( static_cast<_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().count_minimal_n && __gnu_parallel::__is_parallel(__parallelism_tag))) { _DifferenceType __res = 0; __gnu_parallel:: __count_if_selector<_RAIter, _DifferenceType> __functionality; __gnu_parallel:: __for_each_template_random_access( __begin, __end, __pred, __functionality, std::plus<_SequenceIndex>(), __res, __res, -1, __parallelism_tag); return __res; } else return count_if(__begin, __end, __pred, __gnu_parallel::sequential_tag()); } // Sequential fallback for input iterator case. template<typename _IIter, typename _Predicate, typename _IteratorTag> inline typename iterator_traits<_IIter>::difference_type __count_if_switch(_IIter __begin, _IIter __end, _Predicate __pred, _IteratorTag) { return count_if(__begin, __end, __pred, __gnu_parallel::sequential_tag()); } // Public interface. template<typename _IIter, typename _Predicate> inline typename iterator_traits<_IIter>::difference_type count_if(_IIter __begin, _IIter __end, _Predicate __pred, __gnu_parallel::_Parallelism __parallelism_tag) { return __count_if_switch(__begin, __end, __pred, std::__iterator_category(__begin), __parallelism_tag); } template<typename _IIter, typename _Predicate> inline typename iterator_traits<_IIter>::difference_type count_if(_IIter __begin, _IIter __end, _Predicate __pred) { return __count_if_switch(__begin, __end, __pred, std::__iterator_category(__begin)); } // Sequential fallback. template<typename _FIterator1, typename _FIterator2> inline _FIterator1 search(_FIterator1 __begin1, _FIterator1 __end1, _FIterator2 __begin2, _FIterator2 __end2, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::search(__begin1, __end1, __begin2, __end2); } // Parallel algorithm for random access iterator template<typename _RAIter1, typename _RAIter2> _RAIter1 __search_switch(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _RAIter2 __end2, random_access_iterator_tag, random_access_iterator_tag) { typedef typename std::iterator_traits<_RAIter1>::value_type _ValueType1; typedef typename std::iterator_traits<_RAIter2>::value_type _ValueType2; if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end1 - __begin1) >= __gnu_parallel::_Settings::get().search_minimal_n)) return __gnu_parallel:: __search_template( __begin1, __end1, __begin2, __end2, __gnu_parallel::_EqualTo<_ValueType1, _ValueType2>()); else return search(__begin1, __end1, __begin2, __end2, __gnu_parallel::sequential_tag()); } // Sequential fallback for input iterator case template<typename _FIterator1, typename _FIterator2, typename _IteratorTag1, typename _IteratorTag2> inline _FIterator1 __search_switch(_FIterator1 __begin1, _FIterator1 __end1, _FIterator2 __begin2, _FIterator2 __end2, _IteratorTag1, _IteratorTag2) { return search(__begin1, __end1, __begin2, __end2, __gnu_parallel::sequential_tag()); } // Public interface. template<typename _FIterator1, typename _FIterator2> inline _FIterator1 search(_FIterator1 __begin1, _FIterator1 __end1, _FIterator2 __begin2, _FIterator2 __end2) { return __search_switch(__begin1, __end1, __begin2, __end2, std::__iterator_category(__begin1), std::__iterator_category(__begin2)); } // Public interface. template<typename _FIterator1, typename _FIterator2, typename _BinaryPredicate> inline _FIterator1 search(_FIterator1 __begin1, _FIterator1 __end1, _FIterator2 __begin2, _FIterator2 __end2, _BinaryPredicate __pred, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::search( __begin1, __end1, __begin2, __end2, __pred); } // Parallel algorithm for random access iterator. template<typename _RAIter1, typename _RAIter2, typename _BinaryPredicate> _RAIter1 __search_switch(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _RAIter2 __end2, _BinaryPredicate __pred, random_access_iterator_tag, random_access_iterator_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end1 - __begin1) >= __gnu_parallel::_Settings::get().search_minimal_n)) return __gnu_parallel::__search_template(__begin1, __end1, __begin2, __end2, __pred); else return search(__begin1, __end1, __begin2, __end2, __pred, __gnu_parallel::sequential_tag()); } // Sequential fallback for input iterator case template<typename _FIterator1, typename _FIterator2, typename _BinaryPredicate, typename _IteratorTag1, typename _IteratorTag2> inline _FIterator1 __search_switch(_FIterator1 __begin1, _FIterator1 __end1, _FIterator2 __begin2, _FIterator2 __end2, _BinaryPredicate __pred, _IteratorTag1, _IteratorTag2) { return search(__begin1, __end1, __begin2, __end2, __pred, __gnu_parallel::sequential_tag()); } // Public interface template<typename _FIterator1, typename _FIterator2, typename _BinaryPredicate> inline _FIterator1 search(_FIterator1 __begin1, _FIterator1 __end1, _FIterator2 __begin2, _FIterator2 __end2, _BinaryPredicate __pred) { return __search_switch(__begin1, __end1, __begin2, __end2, __pred, std::__iterator_category(__begin1), std::__iterator_category(__begin2)); } #if __cplusplus >= 201703L /* @brief Search a sequence using a Searcher object. * * @param __first A forward iterator. * @param __last A forward iterator. * @param __searcher A callable object. * @return @p __searcher(__first,__last).first / template<typename _ForwardIterator, typename _Searcher> inline _ForwardIterator search(_ForwardIterator __first, _ForwardIterator __last, const _Searcher& __searcher) { return __searcher(__first, __last).first; } #endif // Sequential fallback template<typename _FIterator, typename _Integer, typename _Tp> inline _FIterator search_n(_FIterator __begin, _FIterator __end, _Integer __count, const _Tp& __val, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::search_n(__begin, __end, __count, __val); } // Sequential fallback template<typename _FIterator, typename _Integer, typename _Tp, typename _BinaryPredicate> inline _FIterator search_n(_FIterator __begin, _FIterator __end, _Integer __count, const _Tp& __val, _BinaryPredicate __binary_pred, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::search_n( __begin, __end, __count, __val, __binary_pred); } // Public interface. template<typename _FIterator, typename _Integer, typename _Tp> inline _FIterator search_n(_FIterator __begin, _FIterator __end, _Integer __count, const _Tp& __val) { typedef typename iterator_traits<_FIterator>::value_type _ValueType; return __gnu_parallel::search_n(__begin, __end, __count, __val, __gnu_parallel::_EqualTo<_ValueType, _Tp>()); } // Parallel algorithm for random access iterators. template<typename _RAIter, typename _Integer, typename _Tp, typename _BinaryPredicate> _RAIter __search_n_switch(_RAIter __begin, _RAIter __end, _Integer __count, const _Tp& __val, _BinaryPredicate __binary_pred, random_access_iterator_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().search_minimal_n)) { __gnu_parallel::_PseudoSequence<_Tp, _Integer> __ps(__val, __count); return __gnu_parallel::__search_template( __begin, __end, __ps.begin(), __ps.end(), __binary_pred); } else return _GLIBCXX_STD_A::search_n(__begin, __end, __count, __val, __binary_pred); } // Sequential fallback for input iterator case. template<typename _FIterator, typename _Integer, typename _Tp, typename _BinaryPredicate, typename _IteratorTag> inline _FIterator __search_n_switch(_FIterator __begin, _FIterator __end, _Integer __count, const _Tp& __val, _BinaryPredicate __binary_pred, _IteratorTag) { return _GLIBCXX_STD_A::search_n(__begin, __end, __count, __val, __binary_pred); } // Public interface. template<typename _FIterator, typename _Integer, typename _Tp, typename _BinaryPredicate> inline _FIterator search_n(_FIterator __begin, _FIterator __end, _Integer __count, const _Tp& __val, _BinaryPredicate __binary_pred) { return __search_n_switch(__begin, __end, __count, __val, __binary_pred, std::__iterator_category(__begin)); } // Sequential fallback. template<typename _IIter, typename _OutputIterator, typename _UnaryOperation> inline _OutputIterator transform(_IIter __begin, _IIter __end, _OutputIterator __result, _UnaryOperation __unary_op, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::transform(__begin, __end, __result, __unary_op); } // Parallel unary transform for random access iterators. template<typename _RAIter1, typename _RAIter2, typename _UnaryOperation> _RAIter2 __transform1_switch(_RAIter1 __begin, _RAIter1 __end, _RAIter2 __result, _UnaryOperation __unary_op, random_access_iterator_tag, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().transform_minimal_n && __gnu_parallel::__is_parallel(__parallelism_tag))) { bool __dummy = true; typedef __gnu_parallel::_IteratorPair<_RAIter1, _RAIter2, random_access_iterator_tag> _ItTrip; _ItTrip __begin_pair(__begin, __result), __end_pair(__end, __result + (__end - __begin)); __gnu_parallel::__transform1_selector<_ItTrip> __functionality; __gnu_parallel:: __for_each_template_random_access( __begin_pair, __end_pair, __unary_op, __functionality, __gnu_parallel::_DummyReduct(), __dummy, __dummy, -1, __parallelism_tag); return __functionality._M_finish_iterator; } else return transform(__begin, __end, __result, __unary_op, __gnu_parallel::sequential_tag()); } // Sequential fallback for input iterator case. template<typename _RAIter1, typename _RAIter2, typename _UnaryOperation, typename _IteratorTag1, typename _IteratorTag2> inline _RAIter2 __transform1_switch(_RAIter1 __begin, _RAIter1 __end, _RAIter2 __result, _UnaryOperation __unary_op, _IteratorTag1, _IteratorTag2) { return transform(__begin, __end, __result, __unary_op, __gnu_parallel::sequential_tag()); } // Public interface. template<typename _IIter, typename _OutputIterator, typename _UnaryOperation> inline _OutputIterator transform(_IIter __begin, _IIter __end, _OutputIterator __result, _UnaryOperation __unary_op, __gnu_parallel::_Parallelism __parallelism_tag) { return __transform1_switch(__begin, __end, __result, __unary_op, std::__iterator_category(__begin), std::__iterator_category(__result), __parallelism_tag); } template<typename _IIter, typename _OutputIterator, typename _UnaryOperation> inline _OutputIterator transform(_IIter __begin, _IIter __end, _OutputIterator __result, _UnaryOperation __unary_op) { return __transform1_switch(__begin, __end, __result, __unary_op, std::__iterator_category(__begin), std::__iterator_category(__result)); } // Sequential fallback template<typename _IIter1, typename _IIter2, typename _OutputIterator, typename _BinaryOperation> inline _OutputIterator transform(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _OutputIterator __result, _BinaryOperation __binary_op, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::transform(__begin1, __end1, __begin2, __result, __binary_op); } // Parallel binary transform for random access iterators. template<typename _RAIter1, typename _RAIter2, typename _RAIter3, typename _BinaryOperation> _RAIter3 __transform2_switch(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _RAIter3 __result, _BinaryOperation __binary_op, random_access_iterator_tag, random_access_iterator_tag, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism_tag) { if (_GLIBCXX_PARALLEL_CONDITION( (__end1 - __begin1) >= __gnu_parallel::_Settings::get().transform_minimal_n && __gnu_parallel::__is_parallel(__parallelism_tag))) { bool __dummy = true; typedef __gnu_parallel::_IteratorTriple<_RAIter1, _RAIter2, _RAIter3, random_access_iterator_tag> _ItTrip; _ItTrip __begin_triple(__begin1, __begin2, __result), __end_triple(__end1, __begin2 + (__end1 - __begin1), __result + (__end1 - __begin1)); __gnu_parallel::__transform2_selector<_ItTrip> __functionality; __gnu_parallel:: __for_each_template_random_access(__begin_triple, __end_triple, __binary_op, __functionality, __gnu_parallel::_DummyReduct(), __dummy, __dummy, -1, __parallelism_tag); return __functionality._M_finish_iterator; } else return transform(__begin1, __end1, __begin2, __result, __binary_op, __gnu_parallel::sequential_tag()); } // Sequential fallback for input iterator case. template<typename _IIter1, typename _IIter2, typename _OutputIterator, typename _BinaryOperation, typename _Tag1, typename _Tag2, typename _Tag3> inline _OutputIterator __transform2_switch(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _OutputIterator __result, _BinaryOperation __binary_op, _Tag1, _Tag2, _Tag3) { return transform(__begin1, __end1, __begin2, __result, __binary_op, __gnu_parallel::sequential_tag()); } // Public interface. template<typename _IIter1, typename _IIter2, typename _OutputIterator, typename _BinaryOperation> inline _OutputIterator transform(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _OutputIterator __result, _BinaryOperation __binary_op, __gnu_parallel::_Parallelism __parallelism_tag) { return __transform2_switch( __begin1, __end1, __begin2, __result, __binary_op, std::__iterator_category(__begin1), std::__iterator_category(__begin2), std::__iterator_category(__result), __parallelism_tag); } template<typename _IIter1, typename _IIter2, typename _OutputIterator, typename _BinaryOperation> inline _OutputIterator transform(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _OutputIterator __result, _BinaryOperation __binary_op) { return __transform2_switch( __begin1, __end1, __begin2, __result, __binary_op, std::__iterator_category(__begin1), std::__iterator_category(__begin2), std::__iterator_category(__result)); } // Sequential fallback template<typename _FIterator, typename _Tp> inline void replace(_FIterator __begin, _FIterator __end, const _Tp& __old_value, const _Tp& __new_value, __gnu_parallel::sequential_tag) { _GLIBCXX_STD_A::replace(__begin, __end, __old_value, __new_value); } // Sequential fallback for input iterator case template<typename _FIterator, typename _Tp, typename _IteratorTag> inline void __replace_switch(_FIterator __begin, _FIterator __end, const _Tp& __old_value, const _Tp& __new_value, _IteratorTag) { replace(__begin, __end, __old_value, __new_value, __gnu_parallel::sequential_tag()); } // Parallel replace for random access iterators template<typename _RAIter, typename _Tp> inline void __replace_switch(_RAIter __begin, _RAIter __end, const _Tp& __old_value, const _Tp& __new_value, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism_tag) { // XXX parallel version is where? replace(__begin, __end, __old_value, __new_value, __gnu_parallel::sequential_tag()); } // Public interface template<typename _FIterator, typename _Tp> inline void replace(_FIterator __begin, _FIterator __end, const _Tp& __old_value, const _Tp& __new_value, __gnu_parallel::_Parallelism __parallelism_tag) { __replace_switch(__begin, __end, __old_value, __new_value, std::__iterator_category(__begin), __parallelism_tag); } template<typename _FIterator, typename _Tp> inline void replace(_FIterator __begin, _FIterator __end, const _Tp& __old_value, const _Tp& __new_value) { __replace_switch(__begin, __end, __old_value, __new_value, std::__iterator_category(__begin)); } // Sequential fallback template<typename _FIterator, typename _Predicate, typename _Tp> inline void replace_if(_FIterator __begin, _FIterator __end, _Predicate __pred, const _Tp& __new_value, __gnu_parallel::sequential_tag) { _GLIBCXX_STD_A::replace_if(__begin, __end, __pred, __new_value); } // Sequential fallback for input iterator case template<typename _FIterator, typename _Predicate, typename _Tp, typename _IteratorTag> inline void __replace_if_switch(_FIterator __begin, _FIterator __end, _Predicate __pred, const _Tp& __new_value, _IteratorTag) { replace_if(__begin, __end, __pred, __new_value, __gnu_parallel::sequential_tag()); } // Parallel algorithm for random access iterators. template<typename _RAIter, typename _Predicate, typename _Tp> void __replace_if_switch(_RAIter __begin, _RAIter __end, _Predicate __pred, const _Tp& __new_value, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().replace_minimal_n && __gnu_parallel::__is_parallel(__parallelism_tag))) { bool __dummy; __gnu_parallel:: __replace_if_selector<_RAIter, _Predicate, _Tp> __functionality(__new_value); __gnu_parallel:: __for_each_template_random_access( __begin, __end, __pred, __functionality, __gnu_parallel::_DummyReduct(), true, __dummy, -1, __parallelism_tag); } else replace_if(__begin, __end, __pred, __new_value, __gnu_parallel::sequential_tag()); } // Public interface. template<typename _FIterator, typename _Predicate, typename _Tp> inline void replace_if(_FIterator __begin, _FIterator __end, _Predicate __pred, const _Tp& __new_value, __gnu_parallel::_Parallelism __parallelism_tag) { __replace_if_switch(__begin, __end, __pred, __new_value, std::__iterator_category(__begin), __parallelism_tag); } template<typename _FIterator, typename _Predicate, typename _Tp> inline void replace_if(_FIterator __begin, _FIterator __end, _Predicate __pred, const _Tp& __new_value) { __replace_if_switch(__begin, __end, __pred, __new_value, std::__iterator_category(__begin)); } // Sequential fallback template<typename _FIterator, typename _Generator> inline void generate(_FIterator __begin, _FIterator __end, _Generator __gen, __gnu_parallel::sequential_tag) { _GLIBCXX_STD_A::generate(__begin, __end, __gen); } // Sequential fallback for input iterator case. template<typename _FIterator, typename _Generator, typename _IteratorTag> inline void __generate_switch(_FIterator __begin, _FIterator __end, _Generator __gen, _IteratorTag) { generate(__begin, __end, __gen, __gnu_parallel::sequential_tag()); } // Parallel algorithm for random access iterators. template<typename _RAIter, typename _Generator> void __generate_switch(_RAIter __begin, _RAIter __end, _Generator __gen, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().generate_minimal_n && __gnu_parallel::__is_parallel(__parallelism_tag))) { bool __dummy; __gnu_parallel::__generate_selector<_RAIter> __functionality; __gnu_parallel:: __for_each_template_random_access( __begin, __end, __gen, __functionality, __gnu_parallel::_DummyReduct(), true, __dummy, -1, __parallelism_tag); } else generate(__begin, __end, __gen, __gnu_parallel::sequential_tag()); } // Public interface. template<typename _FIterator, typename _Generator> inline void generate(_FIterator __begin, _FIterator __end, _Generator __gen, __gnu_parallel::_Parallelism __parallelism_tag) { __generate_switch(__begin, __end, __gen, std::__iterator_category(__begin), __parallelism_tag); } template<typename _FIterator, typename _Generator> inline void generate(_FIterator __begin, _FIterator __end, _Generator __gen) { __generate_switch(__begin, __end, __gen, std::__iterator_category(__begin)); } // Sequential fallback. template<typename _OutputIterator, typename _Size, typename _Generator> inline _OutputIterator generate_n(_OutputIterator __begin, _Size __n, _Generator __gen, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::generate_n(__begin, __n, __gen); } // Sequential fallback for input iterator case. template<typename _OutputIterator, typename _Size, typename _Generator, typename _IteratorTag> inline _OutputIterator __generate_n_switch(_OutputIterator __begin, _Size __n, _Generator __gen, _IteratorTag) { return generate_n(__begin, __n, __gen, __gnu_parallel::sequential_tag()); } // Parallel algorithm for random access iterators. template<typename _RAIter, typename _Size, typename _Generator> inline _RAIter __generate_n_switch(_RAIter __begin, _Size __n, _Generator __gen, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism_tag) { // XXX parallel version is where? return generate_n(__begin, __n, __gen, __gnu_parallel::sequential_tag()); } // Public interface. template<typename _OutputIterator, typename _Size, typename _Generator> inline _OutputIterator generate_n(_OutputIterator __begin, _Size __n, _Generator __gen, __gnu_parallel::_Parallelism __parallelism_tag) { return __generate_n_switch(__begin, __n, __gen, std::__iterator_category(__begin), __parallelism_tag); } template<typename _OutputIterator, typename _Size, typename _Generator> inline _OutputIterator generate_n(_OutputIterator __begin, _Size __n, _Generator __gen) { return __generate_n_switch(__begin, __n, __gen, std::__iterator_category(__begin)); } // Sequential fallback. template<typename _RAIter> inline void random_shuffle(_RAIter __begin, _RAIter __end, __gnu_parallel::sequential_tag) { _GLIBCXX_STD_A::random_shuffle(__begin, __end); } // Sequential fallback. template<typename _RAIter, typename _RandomNumberGenerator> inline void random_shuffle(_RAIter __begin, _RAIter __end, _RandomNumberGenerator& __rand, __gnu_parallel::sequential_tag) { _GLIBCXX_STD_A::random_shuffle(__begin, __end, __rand); } /* @brief Functor wrapper for std::rand(). / template<typename _MustBeInt = int> struct _CRandNumber { int operator()(int __limit) { return rand() % __limit; } }; // Fill in random number generator. template<typename _RAIter> inline void random_shuffle(_RAIter __begin, _RAIter __end) { _CRandNumber<> __r; // Parallelization still possible. __gnu_parallel::random_shuffle(__begin, __end, __r); } // Parallel algorithm for random access iterators. template<typename _RAIter, typename _RandomNumberGenerator> void random_shuffle(_RAIter __begin, _RAIter __end, #if __cplusplus >= 201103L _RandomNumberGenerator&& __rand) #else _RandomNumberGenerator& __rand) #endif { if (__begin == __end) return; if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().random_shuffle_minimal_n)) __gnu_parallel::__parallel_random_shuffle(__begin, __end, __rand); else __gnu_parallel::__sequential_random_shuffle(__begin, __end, __rand); } // Sequential fallback. template<typename _FIterator, typename _Predicate> inline _FIterator partition(_FIterator __begin, _FIterator __end, _Predicate __pred, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::partition(__begin, __end, __pred); } // Sequential fallback for input iterator case. template<typename _FIterator, typename _Predicate, typename _IteratorTag> inline _FIterator __partition_switch(_FIterator __begin, _FIterator __end, _Predicate __pred, _IteratorTag) { return partition(__begin, __end, __pred, __gnu_parallel::sequential_tag()); } // Parallel algorithm for random access iterators. template<typename _RAIter, typename _Predicate> _RAIter __partition_switch(_RAIter __begin, _RAIter __end, _Predicate __pred, random_access_iterator_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().partition_minimal_n)) { typedef typename std::iterator_traits<_RAIter>:: difference_type _DifferenceType; _DifferenceType __middle = __gnu_parallel:: __parallel_partition(__begin, __end, __pred, __gnu_parallel::__get_max_threads()); return __begin + __middle; } else return partition(__begin, __end, __pred, __gnu_parallel::sequential_tag()); } // Public interface. template<typename _FIterator, typename _Predicate> inline _FIterator partition(_FIterator __begin, _FIterator __end, _Predicate __pred) { return __partition_switch(__begin, __end, __pred, std::__iterator_category(__begin)); } // sort interface // Sequential fallback template<typename _RAIter> inline void sort(_RAIter __begin, _RAIter __end, __gnu_parallel::sequential_tag) { _GLIBCXX_STD_A::sort(__begin, __end); } // Sequential fallback template<typename _RAIter, typename _Compare> inline void sort(_RAIter __begin, _RAIter __end, _Compare __comp, __gnu_parallel::sequential_tag) { _GLIBCXX_STD_A::sort<_RAIter, _Compare>(__begin, __end, __comp); } // Public interface template<typename _RAIter, typename _Compare, typename _Parallelism> void sort(_RAIter __begin, _RAIter __end, _Compare __comp, _Parallelism __parallelism) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; if (__begin != __end) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().sort_minimal_n)) __gnu_parallel::__parallel_sort<false>( __begin, __end, __comp, __parallelism); else sort(__begin, __end, __comp, __gnu_parallel::sequential_tag()); } } // Public interface, insert default comparator template<typename _RAIter> inline void sort(_RAIter __begin, _RAIter __end) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; sort(__begin, __end, std::less<_ValueType>(), __gnu_parallel::default_parallel_tag()); } // Public interface, insert default comparator template<typename _RAIter> inline void sort(_RAIter __begin, _RAIter __end, __gnu_parallel::default_parallel_tag __parallelism) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; sort(__begin, __end, std::less<_ValueType>(), __parallelism); } // Public interface, insert default comparator template<typename _RAIter> inline void sort(_RAIter __begin, _RAIter __end, __gnu_parallel::parallel_tag __parallelism) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; sort(__begin, __end, std::less<_ValueType>(), __parallelism); } // Public interface, insert default comparator template<typename _RAIter> inline void sort(_RAIter __begin, _RAIter __end, __gnu_parallel::multiway_mergesort_tag __parallelism) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; sort(__begin, __end, std::less<_ValueType>(), __parallelism); } // Public interface, insert default comparator template<typename _RAIter> inline void sort(_RAIter __begin, _RAIter __end, __gnu_parallel::multiway_mergesort_sampling_tag __parallelism) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; sort(__begin, __end, std::less<_ValueType>(), __parallelism); } // Public interface, insert default comparator template<typename _RAIter> inline void sort(_RAIter __begin, _RAIter __end, __gnu_parallel::multiway_mergesort_exact_tag __parallelism) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; sort(__begin, __end, std::less<_ValueType>(), __parallelism); } // Public interface, insert default comparator template<typename _RAIter> inline void sort(_RAIter __begin, _RAIter __end, __gnu_parallel::quicksort_tag __parallelism) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; sort(__begin, __end, std::less<_ValueType>(), __parallelism); } // Public interface, insert default comparator template<typename _RAIter> inline void sort(_RAIter __begin, _RAIter __end, __gnu_parallel::balanced_quicksort_tag __parallelism) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; sort(__begin, __end, std::less<_ValueType>(), __parallelism); } // Public interface template<typename _RAIter, typename _Compare> void sort(_RAIter __begin, _RAIter __end, _Compare __comp) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; sort(__begin, __end, __comp, __gnu_parallel::default_parallel_tag()); } // stable_sort interface // Sequential fallback template<typename _RAIter> inline void stable_sort(_RAIter __begin, _RAIter __end, __gnu_parallel::sequential_tag) { _GLIBCXX_STD_A::stable_sort(__begin, __end); } // Sequential fallback template<typename _RAIter, typename _Compare> inline void stable_sort(_RAIter __begin, _RAIter __end, _Compare __comp, __gnu_parallel::sequential_tag) { _GLIBCXX_STD_A::stable_sort<_RAIter, _Compare>(__begin, __end, __comp); } // Public interface template<typename _RAIter, typename _Compare, typename _Parallelism> void stable_sort(_RAIter __begin, _RAIter __end, _Compare __comp, _Parallelism __parallelism) { typedef iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; if (__begin != __end) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().sort_minimal_n)) __gnu_parallel::__parallel_sort<true>(__begin, __end, __comp, __parallelism); else stable_sort(__begin, __end, __comp, __gnu_parallel::sequential_tag()); } } // Public interface, insert default comparator template<typename _RAIter> inline void stable_sort(_RAIter __begin, _RAIter __end) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; stable_sort(__begin, __end, std::less<_ValueType>(), __gnu_parallel::default_parallel_tag()); } // Public interface, insert default comparator template<typename _RAIter> inline void stable_sort(_RAIter __begin, _RAIter __end, __gnu_parallel::default_parallel_tag __parallelism) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; stable_sort(__begin, __end, std::less<_ValueType>(), __parallelism); } // Public interface, insert default comparator template<typename _RAIter> inline void stable_sort(_RAIter __begin, _RAIter __end, __gnu_parallel::parallel_tag __parallelism) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; stable_sort(__begin, __end, std::less<_ValueType>(), __parallelism); } // Public interface, insert default comparator template<typename _RAIter> inline void stable_sort(_RAIter __begin, _RAIter __end, __gnu_parallel::multiway_mergesort_tag __parallelism) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; stable_sort(__begin, __end, std::less<_ValueType>(), __parallelism); } // Public interface, insert default comparator template<typename _RAIter> inline void stable_sort(_RAIter __begin, _RAIter __end, __gnu_parallel::quicksort_tag __parallelism) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; stable_sort(__begin, __end, std::less<_ValueType>(), __parallelism); } // Public interface, insert default comparator template<typename _RAIter> inline void stable_sort(_RAIter __begin, _RAIter __end, __gnu_parallel::balanced_quicksort_tag __parallelism) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; stable_sort(__begin, __end, std::less<_ValueType>(), __parallelism); } // Public interface template<typename _RAIter, typename _Compare> void stable_sort(_RAIter __begin, _RAIter __end, _Compare __comp) { stable_sort( __begin, __end, __comp, __gnu_parallel::default_parallel_tag()); } // Sequential fallback template<typename _IIter1, typename _IIter2, typename _OutputIterator> inline _OutputIterator merge(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __result, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::merge( __begin1, __end1, __begin2, __end2, __result); } // Sequential fallback template<typename _IIter1, typename _IIter2, typename _OutputIterator, typename _Compare> inline _OutputIterator merge(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __result, _Compare __comp, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::merge( __begin1, __end1, __begin2, __end2, __result, __comp); } // Sequential fallback for input iterator case template<typename _IIter1, typename _IIter2, typename _OutputIterator, typename _Compare, typename _IteratorTag1, typename _IteratorTag2, typename _IteratorTag3> inline _OutputIterator __merge_switch(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __result, _Compare __comp, _IteratorTag1, _IteratorTag2, _IteratorTag3) { return _GLIBCXX_STD_A::merge(__begin1, __end1, __begin2, __end2, __result, __comp); } // Parallel algorithm for random access iterators template<typename _IIter1, typename _IIter2, typename _OutputIterator, typename _Compare> _OutputIterator __merge_switch(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __result, _Compare __comp, random_access_iterator_tag, random_access_iterator_tag, random_access_iterator_tag) { if (_GLIBCXX_PARALLEL_CONDITION( (static_cast<__gnu_parallel::_SequenceIndex>(__end1 - __begin1) >= __gnu_parallel::_Settings::get().merge_minimal_n \|\| static_cast<__gnu_parallel::_SequenceIndex>(__end2 - __begin2) >= __gnu_parallel::_Settings::get().merge_minimal_n))) return __gnu_parallel::__parallel_merge_advance( __begin1, __end1, __begin2, __end2, __result, (__end1 - __begin1) + (__end2 - __begin2), __comp); else return __gnu_parallel::__merge_advance( __begin1, __end1, __begin2, __end2, __result, (__end1 - __begin1) + (__end2 - __begin2), __comp); } // Public interface template<typename _IIter1, typename _IIter2, typename _OutputIterator, typename _Compare> inline _OutputIterator merge(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __result, _Compare __comp) { return __merge_switch( __begin1, __end1, __begin2, __end2, __result, __comp, std::__iterator_category(__begin1), std::__iterator_category(__begin2), std::__iterator_category(__result)); } // Public interface, insert default comparator template<typename _IIter1, typename _IIter2, typename _OutputIterator> inline _OutputIterator merge(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _OutputIterator __result) { typedef typename std::iterator_traits<_IIter1>::value_type _ValueType1; typedef typename std::iterator_traits<_IIter2>::value_type _ValueType2; return __gnu_parallel::merge(__begin1, __end1, __begin2, __end2, __result, __gnu_parallel::_Less<_ValueType1, _ValueType2>()); } // Sequential fallback template<typename _RAIter> inline void nth_element(_RAIter __begin, _RAIter __nth, _RAIter __end, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::nth_element(__begin, __nth, __end); } // Sequential fallback template<typename _RAIter, typename _Compare> inline void nth_element(_RAIter __begin, _RAIter __nth, _RAIter __end, _Compare __comp, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::nth_element(__begin, __nth, __end, __comp); } // Public interface template<typename _RAIter, typename _Compare> inline void nth_element(_RAIter __begin, _RAIter __nth, _RAIter __end, _Compare __comp) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().nth_element_minimal_n)) __gnu_parallel::__parallel_nth_element(__begin, __nth, __end, __comp); else nth_element(__begin, __nth, __end, __comp, __gnu_parallel::sequential_tag()); } // Public interface, insert default comparator template<typename _RAIter> inline void nth_element(_RAIter __begin, _RAIter __nth, _RAIter __end) { typedef typename iterator_traits<_RAIter>::value_type _ValueType; __gnu_parallel::nth_element(__begin, __nth, __end, std::less<_ValueType>()); } // Sequential fallback template<typename _RAIter, typename _Compare> inline void partial_sort(_RAIter __begin, _RAIter __middle, _RAIter __end, _Compare __comp, __gnu_parallel::sequential_tag) { _GLIBCXX_STD_A::partial_sort(__begin, __middle, __end, __comp); } // Sequential fallback template<typename _RAIter> inline void partial_sort(_RAIter __begin, _RAIter __middle, _RAIter __end, __gnu_parallel::sequential_tag) { _GLIBCXX_STD_A::partial_sort(__begin, __middle, __end); } // Public interface, parallel algorithm for random access iterators template<typename _RAIter, typename _Compare> void partial_sort(_RAIter __begin, _RAIter __middle, _RAIter __end, _Compare __comp) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().partial_sort_minimal_n)) __gnu_parallel:: __parallel_partial_sort(__begin, __middle, __end, __comp); else partial_sort(__begin, __middle, __end, __comp, __gnu_parallel::sequential_tag()); } // Public interface, insert default comparator template<typename _RAIter> inline void partial_sort(_RAIter __begin, _RAIter __middle, _RAIter __end) { typedef iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; __gnu_parallel::partial_sort(__begin, __middle, __end, std::less<_ValueType>()); } // Sequential fallback template<typename _FIterator> inline _FIterator max_element(_FIterator __begin, _FIterator __end, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::max_element(__begin, __end); } // Sequential fallback template<typename _FIterator, typename _Compare> inline _FIterator max_element(_FIterator __begin, _FIterator __end, _Compare __comp, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::max_element(__begin, __end, __comp); } // Sequential fallback for input iterator case template<typename _FIterator, typename _Compare, typename _IteratorTag> inline _FIterator __max_element_switch(_FIterator __begin, _FIterator __end, _Compare __comp, _IteratorTag) { return max_element(__begin, __end, __comp, __gnu_parallel::sequential_tag()); } // Parallel algorithm for random access iterators template<typename _RAIter, typename _Compare> _RAIter __max_element_switch(_RAIter __begin, _RAIter __end, _Compare __comp, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().max_element_minimal_n && __gnu_parallel::__is_parallel(__parallelism_tag))) { _RAIter __res(__begin); __gnu_parallel::__identity_selector<_RAIter> __functionality; __gnu_parallel:: __for_each_template_random_access( __begin, __end, __gnu_parallel::_Nothing(), __functionality, __gnu_parallel::__max_element_reduct<_Compare, _RAIter>(__comp), __res, __res, -1, __parallelism_tag); return __res; } else return max_element(__begin, __end, __comp, __gnu_parallel::sequential_tag()); } // Public interface, insert default comparator template<typename _FIterator> inline _FIterator max_element(_FIterator __begin, _FIterator __end, __gnu_parallel::_Parallelism __parallelism_tag) { typedef typename iterator_traits<_FIterator>::value_type _ValueType; return max_element(__begin, __end, std::less<_ValueType>(), __parallelism_tag); } template<typename _FIterator> inline _FIterator max_element(_FIterator __begin, _FIterator __end) { typedef typename iterator_traits<_FIterator>::value_type _ValueType; return __gnu_parallel::max_element(__begin, __end, std::less<_ValueType>()); } // Public interface template<typename _FIterator, typename _Compare> inline _FIterator max_element(_FIterator __begin, _FIterator __end, _Compare __comp, __gnu_parallel::_Parallelism __parallelism_tag) { return __max_element_switch(__begin, __end, __comp, std::__iterator_category(__begin), __parallelism_tag); } template<typename _FIterator, typename _Compare> inline _FIterator max_element(_FIterator __begin, _FIterator __end, _Compare __comp) { return __max_element_switch(__begin, __end, __comp, std::__iterator_category(__begin)); } // Sequential fallback template<typename _FIterator> inline _FIterator min_element(_FIterator __begin, _FIterator __end, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::min_element(__begin, __end); } // Sequential fallback template<typename _FIterator, typename _Compare> inline _FIterator min_element(_FIterator __begin, _FIterator __end, _Compare __comp, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::min_element(__begin, __end, __comp); } // Sequential fallback for input iterator case template<typename _FIterator, typename _Compare, typename _IteratorTag> inline _FIterator __min_element_switch(_FIterator __begin, _FIterator __end, _Compare __comp, _IteratorTag) { return min_element(__begin, __end, __comp, __gnu_parallel::sequential_tag()); } // Parallel algorithm for random access iterators template<typename _RAIter, typename _Compare> _RAIter __min_element_switch(_RAIter __begin, _RAIter __end, _Compare __comp, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().min_element_minimal_n && __gnu_parallel::__is_parallel(__parallelism_tag))) { _RAIter __res(__begin); __gnu_parallel::__identity_selector<_RAIter> __functionality; __gnu_parallel:: __for_each_template_random_access( __begin, __end, __gnu_parallel::_Nothing(), __functionality, __gnu_parallel::__min_element_reduct<_Compare, _RAIter>(__comp), __res, __res, -1, __parallelism_tag); return __res; } else return min_element(__begin, __end, __comp, __gnu_parallel::sequential_tag()); } // Public interface, insert default comparator template<typename _FIterator> inline _FIterator min_element(_FIterator __begin, _FIterator __end, __gnu_parallel::_Parallelism __parallelism_tag) { typedef typename iterator_traits<_FIterator>::value_type _ValueType; return min_element(__begin, __end, std::less<_ValueType>(), __parallelism_tag); } template<typename _FIterator> inline _FIterator min_element(_FIterator __begin, _FIterator __end) { typedef typename iterator_traits<_FIterator>::value_type _ValueType; return __gnu_parallel::min_element(__begin, __end, std::less<_ValueType>()); } // Public interface template<typename _FIterator, typename _Compare> inline _FIterator min_element(_FIterator __begin, _FIterator __end, _Compare __comp, __gnu_parallel::_Parallelism __parallelism_tag) { return __min_element_switch(__begin, __end, __comp, std::__iterator_category(__begin), __parallelism_tag); } template<typename _FIterator, typename _Compare> inline _FIterator min_element(_FIterator __begin, _FIterator __end, _Compare __comp) { return __min_element_switch(__begin, __end, __comp, std::__iterator_category(__begin)); } #if __cplusplus >= 201703L using _GLIBCXX_STD_A::for_each_n; using _GLIBCXX_STD_A::sample; #endif } // end namespace } // end namespace #endif / _GLIBCXX_PARALLEL_ALGO_H */	78.77 KB	2025-09-15 15:41
📄 algobase.h // -- C++ -- // Copyright (C) 2007-2021 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/algobase.h * @brief Parallel STL function calls corresponding to the * stl_algobase.h header. The functions defined here mainly do case * switches and call the actual parallelized versions in other files. * Inlining policy: Functions that basically only contain one * function call, are declared inline. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler and Felix Putze. #ifndef _GLIBCXX_PARALLEL_ALGOBASE_H #define _GLIBCXX_PARALLEL_ALGOBASE_H 1 #include <bits/stl_algobase.h> #include <parallel/base.h> #include <parallel/algorithmfwd.h> #include <parallel/find.h> #include <parallel/find_selectors.h> namespace std _GLIBCXX_VISIBILITY(default) { namespace __parallel { // NB: equal and lexicographical_compare require mismatch. // Sequential fallback template<typename _IIter1, typename _IIter2> inline pair<_IIter1, _IIter2> mismatch(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::mismatch(__begin1, __end1, __begin2); } // Sequential fallback template<typename _IIter1, typename _IIter2, typename _Predicate> inline pair<_IIter1, _IIter2> mismatch(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _Predicate __pred, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::mismatch(__begin1, __end1, __begin2, __pred); } // Sequential fallback for input iterator case template<typename _IIter1, typename _IIter2, typename _Predicate, typename _IteratorTag1, typename _IteratorTag2> inline pair<_IIter1, _IIter2> __mismatch_switch(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _Predicate __pred, _IteratorTag1, _IteratorTag2) { return _GLIBCXX_STD_A::mismatch(__begin1, __end1, __begin2, __pred); } // Parallel mismatch for random access iterators template<typename _RAIter1, typename _RAIter2, typename _Predicate> pair<_RAIter1, _RAIter2> __mismatch_switch(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _Predicate __pred, random_access_iterator_tag, random_access_iterator_tag) { if (_GLIBCXX_PARALLEL_CONDITION(true)) { _RAIter1 __res = __gnu_parallel::__find_template(__begin1, __end1, __begin2, __pred, __gnu_parallel:: __mismatch_selector()).first; return make_pair(__res , __begin2 + (__res - __begin1)); } else return _GLIBCXX_STD_A::mismatch(__begin1, __end1, __begin2, __pred); } // Public interface template<typename _IIter1, typename _IIter2> inline pair<_IIter1, _IIter2> mismatch(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2) { typedef __gnu_parallel::_EqualTo< typename std::iterator_traits<_IIter1>::value_type, typename std::iterator_traits<_IIter2>::value_type> _EqualTo; return __mismatch_switch(__begin1, __end1, __begin2, _EqualTo(), std::__iterator_category(__begin1), std::__iterator_category(__begin2)); } // Public interface template<typename _IIter1, typename _IIter2, typename _Predicate> inline pair<_IIter1, _IIter2> mismatch(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _Predicate __pred) { return __mismatch_switch(__begin1, __end1, __begin2, __pred, std::__iterator_category(__begin1), std::__iterator_category(__begin2)); } #if __cplusplus > 201103L // Sequential fallback. template<typename _InputIterator1, typename _InputIterator2> inline pair<_InputIterator1, _InputIterator2> mismatch(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::mismatch(__first1, __last1, __first2, __last2); } // Sequential fallback. template<typename _InputIterator1, typename _InputIterator2, typename _BinaryPredicate> inline pair<_InputIterator1, _InputIterator2> mismatch(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2, _BinaryPredicate __binary_pred, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::mismatch(__first1, __last1, __first2, __last2, __binary_pred); } // Sequential fallback for input iterator case template<typename _IIter1, typename _IIter2, typename _Predicate, typename _IteratorTag1, typename _IteratorTag2> inline pair<_IIter1, _IIter2> __mismatch_switch(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _Predicate __pred, _IteratorTag1, _IteratorTag2) { return _GLIBCXX_STD_A::mismatch(__begin1, __end1, __begin2, __end2, __pred); } // Parallel mismatch for random access iterators template<typename _RAIter1, typename _RAIter2, typename _Predicate> pair<_RAIter1, _RAIter2> __mismatch_switch(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _RAIter2 __end2, _Predicate __pred, random_access_iterator_tag, random_access_iterator_tag) { if (_GLIBCXX_PARALLEL_CONDITION(true)) { if ((__end2 - __begin2) < (__end1 - __begin1)) __end1 = __begin1 + (__end2 - __begin2); _RAIter1 __res = __gnu_parallel::__find_template(__begin1, __end1, __begin2, __pred, __gnu_parallel:: __mismatch_selector()).first; return make_pair(__res , __begin2 + (__res - __begin1)); } else return _GLIBCXX_STD_A::mismatch(__begin1, __end1, __begin2, __end2, __pred); } template<typename _IIter1, typename _IIter2> inline pair<_IIter1, _IIter2> mismatch(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2) { typedef __gnu_parallel::_EqualTo< typename std::iterator_traits<_IIter1>::value_type, typename std::iterator_traits<_IIter2>::value_type> _EqualTo; return __mismatch_switch(__begin1, __end1, __begin2, __end2, _EqualTo(), std::__iterator_category(__begin1), std::__iterator_category(__begin2)); } template<typename _InputIterator1, typename _InputIterator2, typename _BinaryPredicate> inline pair<_InputIterator1, _InputIterator2> mismatch(_InputIterator1 __begin1, _InputIterator1 __end1, _InputIterator2 __begin2, _InputIterator2 __end2, _BinaryPredicate __binary_pred) { return __mismatch_switch(__begin1, __end1, __begin2, __end2, __binary_pred, std::__iterator_category(__begin1), std::__iterator_category(__begin2)); } #endif // Sequential fallback template<typename _IIter1, typename _IIter2> inline bool equal(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::equal(__begin1, __end1, __begin2); } // Sequential fallback template<typename _IIter1, typename _IIter2, typename _Predicate> inline bool equal(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _Predicate __pred, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::equal(__begin1, __end1, __begin2, __pred); } // Public interface template<typename _IIter1, typename _IIter2> _GLIBCXX20_CONSTEXPR inline bool equal(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2) { #if __cplusplus > 201703L if (std::is_constant_evaluated()) return _GLIBCXX_STD_A::equal(__begin1, __end1, __begin2); #endif return __gnu_parallel::mismatch(__begin1, __end1, __begin2).first == __end1; } // Public interface template<typename _IIter1, typename _IIter2, typename _Predicate> _GLIBCXX20_CONSTEXPR inline bool equal(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _Predicate __pred) { #if __cplusplus > 201703L if (std::is_constant_evaluated()) return _GLIBCXX_STD_A::equal(__begin1, __end1, __begin2, __pred); #endif return __gnu_parallel::mismatch(__begin1, __end1, __begin2, __pred).first == __end1; } #if __cplusplus > 201103L // Sequential fallback template<typename _IIter1, typename _IIter2> inline bool equal(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::equal(__begin1, __end1, __begin2, __end2); } // Sequential fallback template<typename _IIter1, typename _IIter2, typename _BinaryPredicate> inline bool equal(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _BinaryPredicate __binary_pred, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::equal(__begin1, __end1, __begin2, __end2, __binary_pred); } // Sequential fallback for input iterator case template<typename _IIter1, typename _IIter2, typename _Predicate, typename _IteratorTag1, typename _IteratorTag2> inline bool __equal_switch(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _Predicate __pred, _IteratorTag1, _IteratorTag2) { return _GLIBCXX_STD_A::equal(__begin1, __end1, __begin2, __end2, __pred); } // Parallel equal for random access iterators template<typename _RAIter1, typename _RAIter2, typename _Predicate> inline bool __equal_switch(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _RAIter2 __end2, _Predicate __pred, random_access_iterator_tag, random_access_iterator_tag) { if (_GLIBCXX_PARALLEL_CONDITION(true)) { if (std::distance(__begin1, __end1) != std::distance(__begin2, __end2)) return false; return __gnu_parallel::mismatch(__begin1, __end1, __begin2, __end2, __pred).first == __end1; } else return _GLIBCXX_STD_A::equal(__begin1, __end1, __begin2, __end2, __pred); } template<typename _IIter1, typename _IIter2> _GLIBCXX20_CONSTEXPR inline bool equal(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2) { #if __cplusplus > 201703L if (std::is_constant_evaluated()) return _GLIBCXX_STD_A::equal(__begin1, __end1, __begin2, __end2); #endif typedef __gnu_parallel::_EqualTo< typename std::iterator_traits<_IIter1>::value_type, typename std::iterator_traits<_IIter2>::value_type> _EqualTo; return __equal_switch(__begin1, __end1, __begin2, __end2, _EqualTo(), std::__iterator_category(__begin1), std::__iterator_category(__begin2)); } template<typename _IIter1, typename _IIter2, typename _BinaryPredicate> _GLIBCXX20_CONSTEXPR inline bool equal(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _BinaryPredicate __binary_pred) { #if __cplusplus > 201703L if (std::is_constant_evaluated()) return _GLIBCXX_STD_A::equal(__begin1, __end1, __begin2, __end2, __binary_pred); #endif return __equal_switch(__begin1, __end1, __begin2, __end2, __binary_pred, std::__iterator_category(__begin1), std::__iterator_category(__begin2)); } #endif // C++14 // Sequential fallback template<typename _IIter1, typename _IIter2> inline bool lexicographical_compare(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::lexicographical_compare(__begin1, __end1, __begin2, __end2); } // Sequential fallback template<typename _IIter1, typename _IIter2, typename _Predicate> inline bool lexicographical_compare(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _Predicate __pred, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::lexicographical_compare( __begin1, __end1, __begin2, __end2, __pred); } // Sequential fallback for input iterator case template<typename _IIter1, typename _IIter2, typename _Predicate, typename _IteratorTag1, typename _IteratorTag2> inline bool __lexicographical_compare_switch(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _Predicate __pred, _IteratorTag1, _IteratorTag2) { return _GLIBCXX_STD_A::lexicographical_compare( __begin1, __end1, __begin2, __end2, __pred); } // Parallel lexicographical_compare for random access iterators // Limitation: Both valuetypes must be the same template<typename _RAIter1, typename _RAIter2, typename _Predicate> bool __lexicographical_compare_switch(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _RAIter2 __end2, _Predicate __pred, random_access_iterator_tag, random_access_iterator_tag) { if (_GLIBCXX_PARALLEL_CONDITION(true)) { typedef iterator_traits<_RAIter1> _TraitsType1; typedef typename _TraitsType1::value_type _ValueType1; typedef iterator_traits<_RAIter2> _TraitsType2; typedef typename _TraitsType2::value_type _ValueType2; typedef __gnu_parallel:: _EqualFromLess<_ValueType1, _ValueType2, _Predicate> _EqualFromLessCompare; // Longer sequence in first place. if ((__end1 - __begin1) < (__end2 - __begin2)) { typedef pair<_RAIter1, _RAIter2> _SpotType; _SpotType __mm = __mismatch_switch(__begin1, __end1, __begin2, _EqualFromLessCompare(__pred), random_access_iterator_tag(), random_access_iterator_tag()); return (__mm.first == __end1) \|\| bool(__pred(__mm.first, __mm.second)); } else { typedef pair<_RAIter2, _RAIter1> _SpotType; _SpotType __mm = __mismatch_switch(__begin2, __end2, __begin1, _EqualFromLessCompare(__pred), random_access_iterator_tag(), random_access_iterator_tag()); return (__mm.first != __end2) && bool(__pred(__mm.second, __mm.first)); } } else return _GLIBCXX_STD_A::lexicographical_compare( __begin1, __end1, __begin2, __end2, __pred); } // Public interface template<typename _IIter1, typename _IIter2> _GLIBCXX20_CONSTEXPR inline bool lexicographical_compare(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2) { #if __cplusplus > 201703L if (std::is_constant_evaluated()) return _GLIBCXX_STD_A::lexicographical_compare(__begin1, __end1, __begin2, __end2); #endif typedef iterator_traits<_IIter1> _TraitsType1; typedef typename _TraitsType1::value_type _ValueType1; typedef typename _TraitsType1::iterator_category _IteratorCategory1; typedef iterator_traits<_IIter2> _TraitsType2; typedef typename _TraitsType2::value_type _ValueType2; typedef typename _TraitsType2::iterator_category _IteratorCategory2; typedef __gnu_parallel::_Less<_ValueType1, _ValueType2> _LessType; return __lexicographical_compare_switch( __begin1, __end1, __begin2, __end2, _LessType(), _IteratorCategory1(), _IteratorCategory2()); } // Public interface template<typename _IIter1, typename _IIter2, typename _Predicate> _GLIBCXX20_CONSTEXPR inline bool lexicographical_compare(_IIter1 __begin1, _IIter1 __end1, _IIter2 __begin2, _IIter2 __end2, _Predicate __pred) { #if __cplusplus > 201703L if (std::is_constant_evaluated()) return _GLIBCXX_STD_A::lexicographical_compare(__begin1, __end1, __begin2, __end2, __pred); #endif typedef iterator_traits<_IIter1> _TraitsType1; typedef typename _TraitsType1::iterator_category _IteratorCategory1; typedef iterator_traits<_IIter2> _TraitsType2; typedef typename _TraitsType2::iterator_category _IteratorCategory2; return __lexicographical_compare_switch( __begin1, __end1, __begin2, __end2, __pred, _IteratorCategory1(), _IteratorCategory2()); } #if __cpp_lib_three_way_comparison using _GLIBCXX_STD_A::lexicographical_compare_three_way; #endif } // end namespace } // end namespace #endif / _GLIBCXX_PARALLEL_ALGOBASE_H */	17.93 KB	2025-09-15 15:41
📄 algorithm // Algorithm extensions -- C++ -- // Copyright (C) 2007-2021 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/algorithm * This file is a GNU extension to the Standard C++ Library. */ #ifndef _PARALLEL_ALGORITHM #define _PARALLEL_ALGORITHM 1 #pragma GCC system_header #include <algorithm> #include <parallel/algorithmfwd.h> #include <parallel/algobase.h> #include <parallel/algo.h> #endif	1.35 KB	2025-09-15 15:41
📄 algorithmfwd.h // <parallel/algorithm> Forward declarations -- C++ -- // Copyright (C) 2007-2021 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/algorithmfwd.h * This file is a GNU parallel extension to the Standard C++ Library. / #ifndef _GLIBCXX_PARALLEL_ALGORITHMFWD_H #define _GLIBCXX_PARALLEL_ALGORITHMFWD_H 1 #pragma GCC system_header #include <parallel/tags.h> #include <parallel/settings.h> namespace std _GLIBCXX_VISIBILITY(default) { namespace __parallel { template<typename _FIter> _FIter adjacent_find(_FIter, _FIter); template<typename _FIter> _FIter adjacent_find(_FIter, _FIter, __gnu_parallel::sequential_tag); template<typename _FIter, typename _IterTag> _FIter __adjacent_find_switch(_FIter, _FIter, _IterTag); template<typename _RAIter> _RAIter __adjacent_find_switch(_RAIter, _RAIter, random_access_iterator_tag); template<typename _FIter, typename _BiPredicate> _FIter adjacent_find(_FIter, _FIter, _BiPredicate); template<typename _FIter, typename _BiPredicate> _FIter adjacent_find(_FIter, _FIter, _BiPredicate, __gnu_parallel::sequential_tag); template<typename _FIter, typename _BiPredicate, typename _IterTag> _FIter __adjacent_find_switch(_FIter, _FIter, _BiPredicate, _IterTag); template<typename _RAIter, typename _BiPredicate> _RAIter __adjacent_find_switch(_RAIter, _RAIter, _BiPredicate, random_access_iterator_tag); template<typename _IIter, typename _Tp> typename iterator_traits<_IIter>::difference_type count(_IIter, _IIter, const _Tp&); template<typename _IIter, typename _Tp> typename iterator_traits<_IIter>::difference_type count(_IIter, _IIter, const _Tp&, __gnu_parallel::sequential_tag); template<typename _IIter, typename _Tp> typename iterator_traits<_IIter>::difference_type count(_IIter, _IIter, const _Tp&, __gnu_parallel::_Parallelism); template<typename _IIter, typename _Tp, typename _IterTag> typename iterator_traits<_IIter>::difference_type __count_switch(_IIter, _IIter, const _Tp&, _IterTag); template<typename _RAIter, typename _Tp> typename iterator_traits<_RAIter>::difference_type __count_switch(_RAIter, _RAIter, const _Tp&, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism = __gnu_parallel::parallel_unbalanced); template<typename _IIter, typename _Predicate> typename iterator_traits<_IIter>::difference_type count_if(_IIter, _IIter, _Predicate); template<typename _IIter, typename _Predicate> typename iterator_traits<_IIter>::difference_type count_if(_IIter, _IIter, _Predicate, __gnu_parallel::sequential_tag); template<typename _IIter, typename _Predicate> typename iterator_traits<_IIter>::difference_type count_if(_IIter, _IIter, _Predicate, __gnu_parallel::_Parallelism); template<typename _IIter, typename _Predicate, typename _IterTag> typename iterator_traits<_IIter>::difference_type __count_if_switch(_IIter, _IIter, _Predicate, _IterTag); template<typename _RAIter, typename _Predicate> typename iterator_traits<_RAIter>::difference_type __count_if_switch(_RAIter, _RAIter, _Predicate, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism = __gnu_parallel::parallel_unbalanced); // algobase.h template<typename _IIter1, typename _IIter2> bool equal(_IIter1, _IIter1, _IIter2, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2, typename _Predicate> bool equal(_IIter1, _IIter1, _IIter2, _Predicate, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2> _GLIBCXX20_CONSTEXPR bool equal(_IIter1, _IIter1, _IIter2); template<typename _IIter1, typename _IIter2, typename _Predicate> _GLIBCXX20_CONSTEXPR bool equal(_IIter1, _IIter1, _IIter2, _Predicate); template<typename _IIter, typename _Tp> _IIter find(_IIter, _IIter, const _Tp&, __gnu_parallel::sequential_tag); template<typename _IIter, typename _Tp> _IIter find(_IIter, _IIter, const _Tp& __val); template<typename _IIter, typename _Tp, typename _IterTag> _IIter __find_switch(_IIter, _IIter, const _Tp&, _IterTag); template<typename _RAIter, typename _Tp> _RAIter __find_switch(_RAIter, _RAIter, const _Tp&, random_access_iterator_tag); template<typename _IIter, typename _Predicate> _IIter find_if(_IIter, _IIter, _Predicate, __gnu_parallel::sequential_tag); template<typename _IIter, typename _Predicate> _IIter find_if(_IIter, _IIter, _Predicate); template<typename _IIter, typename _Predicate, typename _IterTag> _IIter __find_if_switch(_IIter, _IIter, _Predicate, _IterTag); template<typename _RAIter, typename _Predicate> _RAIter __find_if_switch(_RAIter, _RAIter, _Predicate, random_access_iterator_tag); template<typename _IIter, typename _FIter> _IIter find_first_of(_IIter, _IIter, _FIter, _FIter, __gnu_parallel::sequential_tag); template<typename _IIter, typename _FIter, typename _BiPredicate> _IIter find_first_of(_IIter, _IIter, _FIter, _FIter, _BiPredicate, __gnu_parallel::sequential_tag); template<typename _IIter, typename _FIter, typename _BiPredicate> _IIter find_first_of(_IIter, _IIter, _FIter, _FIter, _BiPredicate); template<typename _IIter, typename _FIter> _IIter find_first_of(_IIter, _IIter, _FIter, _FIter); template<typename _IIter, typename _FIter, typename _IterTag1, typename _IterTag2> _IIter __find_first_of_switch( _IIter, _IIter, _FIter, _FIter, _IterTag1, _IterTag2); template<typename _RAIter, typename _FIter, typename _BiPredicate, typename _IterTag> _RAIter __find_first_of_switch(_RAIter, _RAIter, _FIter, _FIter, _BiPredicate, random_access_iterator_tag, _IterTag); template<typename _IIter, typename _FIter, typename _BiPredicate, typename _IterTag1, typename _IterTag2> _IIter __find_first_of_switch(_IIter, _IIter, _FIter, _FIter, _BiPredicate, _IterTag1, _IterTag2); template<typename _IIter, typename _Function> _Function for_each(_IIter, _IIter, _Function); template<typename _IIter, typename _Function> _Function for_each(_IIter, _IIter, _Function, __gnu_parallel::sequential_tag); template<typename _Iterator, typename _Function> _Function for_each(_Iterator, _Iterator, _Function, __gnu_parallel::_Parallelism); template<typename _IIter, typename _Function, typename _IterTag> _Function __for_each_switch(_IIter, _IIter, _Function, _IterTag); template<typename _RAIter, typename _Function> _Function __for_each_switch(_RAIter, _RAIter, _Function, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism = __gnu_parallel::parallel_balanced); template<typename _FIter, typename _Generator> void generate(_FIter, _FIter, _Generator); template<typename _FIter, typename _Generator> void generate(_FIter, _FIter, _Generator, __gnu_parallel::sequential_tag); template<typename _FIter, typename _Generator> void generate(_FIter, _FIter, _Generator, __gnu_parallel::_Parallelism); template<typename _FIter, typename _Generator, typename _IterTag> void __generate_switch(_FIter, _FIter, _Generator, _IterTag); template<typename _RAIter, typename _Generator> void __generate_switch(_RAIter, _RAIter, _Generator, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism = __gnu_parallel::parallel_balanced); template<typename _OIter, typename _Size, typename _Generator> _OIter generate_n(_OIter, _Size, _Generator); template<typename _OIter, typename _Size, typename _Generator> _OIter generate_n(_OIter, _Size, _Generator, __gnu_parallel::sequential_tag); template<typename _OIter, typename _Size, typename _Generator> _OIter generate_n(_OIter, _Size, _Generator, __gnu_parallel::_Parallelism); template<typename _OIter, typename _Size, typename _Generator, typename _IterTag> _OIter __generate_n_switch(_OIter, _Size, _Generator, _IterTag); template<typename _RAIter, typename _Size, typename _Generator> _RAIter __generate_n_switch(_RAIter, _Size, _Generator, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism = __gnu_parallel::parallel_balanced); template<typename _IIter1, typename _IIter2> bool lexicographical_compare(_IIter1, _IIter1, _IIter2, _IIter2, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2, typename _Predicate> bool lexicographical_compare(_IIter1, _IIter1, _IIter2, _IIter2, _Predicate, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2> _GLIBCXX20_CONSTEXPR bool lexicographical_compare(_IIter1, _IIter1, _IIter2, _IIter2); template<typename _IIter1, typename _IIter2, typename _Predicate> _GLIBCXX20_CONSTEXPR bool lexicographical_compare(_IIter1, _IIter1, _IIter2, _IIter2, _Predicate); template<typename _IIter1, typename _IIter2, typename _Predicate, typename _IterTag1, typename _IterTag2> bool __lexicographical_compare_switch(_IIter1, _IIter1, _IIter2, _IIter2, _Predicate, _IterTag1, _IterTag2); template<typename _RAIter1, typename _RAIter2, typename _Predicate> bool __lexicographical_compare_switch(_RAIter1, _RAIter1, _RAIter2, _RAIter2, _Predicate, random_access_iterator_tag, random_access_iterator_tag); // algo.h template<typename _IIter1, typename _IIter2> pair<_IIter1, _IIter2> mismatch(_IIter1, _IIter1, _IIter2, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2, typename _Predicate> pair<_IIter1, _IIter2> mismatch(_IIter1, _IIter1, _IIter2, _Predicate, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2> pair<_IIter1, _IIter2> mismatch(_IIter1, _IIter1, _IIter2); template<typename _IIter1, typename _IIter2, typename _Predicate> pair<_IIter1, _IIter2> mismatch(_IIter1, _IIter1, _IIter2, _Predicate); template<typename _IIter1, typename _IIter2, typename _Predicate, typename _IterTag1, typename _IterTag2> pair<_IIter1, _IIter2> __mismatch_switch(_IIter1, _IIter1, _IIter2, _Predicate, _IterTag1, _IterTag2); template<typename _RAIter1, typename _RAIter2, typename _Predicate> pair<_RAIter1, _RAIter2> __mismatch_switch(_RAIter1, _RAIter1, _RAIter2, _Predicate, random_access_iterator_tag, random_access_iterator_tag); template<typename _FIter1, typename _FIter2> _FIter1 search(_FIter1, _FIter1, _FIter2, _FIter2, __gnu_parallel::sequential_tag); template<typename _FIter1, typename _FIter2> _FIter1 search(_FIter1, _FIter1, _FIter2, _FIter2); template<typename _FIter1, typename _FIter2, typename _BiPredicate> _FIter1 search(_FIter1, _FIter1, _FIter2, _FIter2, _BiPredicate, __gnu_parallel::sequential_tag); template<typename _FIter1, typename _FIter2, typename _BiPredicate> _FIter1 search(_FIter1, _FIter1, _FIter2, _FIter2, _BiPredicate); template<typename _RAIter1, typename _RAIter2> _RAIter1 __search_switch(_RAIter1, _RAIter1, _RAIter2, _RAIter2, random_access_iterator_tag, random_access_iterator_tag); template<typename _FIter1, typename _FIter2, typename _IterTag1, typename _IterTag2> _FIter1 __search_switch(_FIter1, _FIter1, _FIter2, _FIter2, _IterTag1, _IterTag2); template<typename _RAIter1, typename _RAIter2, typename _BiPredicate> _RAIter1 __search_switch(_RAIter1, _RAIter1, _RAIter2, _RAIter2, _BiPredicate, random_access_iterator_tag, random_access_iterator_tag); template<typename _FIter1, typename _FIter2, typename _BiPredicate, typename _IterTag1, typename _IterTag2> _FIter1 __search_switch(_FIter1, _FIter1, _FIter2, _FIter2, _BiPredicate, _IterTag1, _IterTag2); template<typename _FIter, typename _Integer, typename _Tp> _FIter search_n(_FIter, _FIter, _Integer, const _Tp&, __gnu_parallel::sequential_tag); template<typename _FIter, typename _Integer, typename _Tp, typename _BiPredicate> _FIter search_n(_FIter, _FIter, _Integer, const _Tp&, _BiPredicate, __gnu_parallel::sequential_tag); template<typename _FIter, typename _Integer, typename _Tp> _FIter search_n(_FIter, _FIter, _Integer, const _Tp&); template<typename _FIter, typename _Integer, typename _Tp, typename _BiPredicate> _FIter search_n(_FIter, _FIter, _Integer, const _Tp&, _BiPredicate); template<typename _RAIter, typename _Integer, typename _Tp, typename _BiPredicate> _RAIter __search_n_switch(_RAIter, _RAIter, _Integer, const _Tp&, _BiPredicate, random_access_iterator_tag); template<typename _FIter, typename _Integer, typename _Tp, typename _BiPredicate, typename _IterTag> _FIter __search_n_switch(_FIter, _FIter, _Integer, const _Tp&, _BiPredicate, _IterTag); template<typename _IIter, typename _OIter, typename _UnaryOperation> _OIter transform(_IIter, _IIter, _OIter, _UnaryOperation); template<typename _IIter, typename _OIter, typename _UnaryOperation> _OIter transform(_IIter, _IIter, _OIter, _UnaryOperation, __gnu_parallel::sequential_tag); template<typename _IIter, typename _OIter, typename _UnaryOperation> _OIter transform(_IIter, _IIter, _OIter, _UnaryOperation, __gnu_parallel::_Parallelism); template<typename _IIter, typename _OIter, typename _UnaryOperation, typename _IterTag1, typename _IterTag2> _OIter __transform1_switch(_IIter, _IIter, _OIter, _UnaryOperation, _IterTag1, _IterTag2); template<typename _RAIIter, typename _RAOIter, typename _UnaryOperation> _RAOIter __transform1_switch(_RAIIter, _RAIIter, _RAOIter, _UnaryOperation, random_access_iterator_tag, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism = __gnu_parallel::parallel_balanced); template<typename _IIter1, typename _IIter2, typename _OIter, typename _BiOperation> _OIter transform(_IIter1, _IIter1, _IIter2, _OIter, _BiOperation); template<typename _IIter1, typename _IIter2, typename _OIter, typename _BiOperation> _OIter transform(_IIter1, _IIter1, _IIter2, _OIter, _BiOperation, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2, typename _OIter, typename _BiOperation> _OIter transform(_IIter1, _IIter1, _IIter2, _OIter, _BiOperation, __gnu_parallel::_Parallelism); template<typename _RAIter1, typename _RAIter2, typename _RAIter3, typename _BiOperation> _RAIter3 __transform2_switch(_RAIter1, _RAIter1, _RAIter2, _RAIter3, _BiOperation, random_access_iterator_tag, random_access_iterator_tag, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism = __gnu_parallel::parallel_balanced); template<typename _IIter1, typename _IIter2, typename _OIter, typename _BiOperation, typename _Tag1, typename _Tag2, typename _Tag3> _OIter __transform2_switch(_IIter1, _IIter1, _IIter2, _OIter, _BiOperation, _Tag1, _Tag2, _Tag3); template<typename _FIter, typename _Tp> void replace(_FIter, _FIter, const _Tp&, const _Tp&); template<typename _FIter, typename _Tp> void replace(_FIter, _FIter, const _Tp&, const _Tp&, __gnu_parallel::sequential_tag); template<typename _FIter, typename _Tp> void replace(_FIter, _FIter, const _Tp&, const _Tp&, __gnu_parallel::_Parallelism); template<typename _FIter, typename _Tp, typename _IterTag> void __replace_switch(_FIter, _FIter, const _Tp&, const _Tp&, _IterTag); template<typename _RAIter, typename _Tp> void __replace_switch(_RAIter, _RAIter, const _Tp&, const _Tp&, random_access_iterator_tag, __gnu_parallel::_Parallelism); template<typename _FIter, typename _Predicate, typename _Tp> void replace_if(_FIter, _FIter, _Predicate, const _Tp&); template<typename _FIter, typename _Predicate, typename _Tp> void replace_if(_FIter, _FIter, _Predicate, const _Tp&, __gnu_parallel::sequential_tag); template<typename _FIter, typename _Predicate, typename _Tp> void replace_if(_FIter, _FIter, _Predicate, const _Tp&, __gnu_parallel::_Parallelism); template<typename _FIter, typename _Predicate, typename _Tp, typename _IterTag> void __replace_if_switch(_FIter, _FIter, _Predicate, const _Tp&, _IterTag); template<typename _RAIter, typename _Predicate, typename _Tp> void __replace_if_switch(_RAIter, _RAIter, _Predicate, const _Tp&, random_access_iterator_tag, __gnu_parallel::_Parallelism); template<typename _FIter> _FIter max_element(_FIter, _FIter); template<typename _FIter> _FIter max_element(_FIter, _FIter, __gnu_parallel::sequential_tag); template<typename _FIter> _FIter max_element(_FIter, _FIter, __gnu_parallel::_Parallelism); template<typename _FIter, typename _Compare> _FIter max_element(_FIter, _FIter, _Compare); template<typename _FIter, typename _Compare> _FIter max_element(_FIter, _FIter, _Compare, __gnu_parallel::sequential_tag); template<typename _FIter, typename _Compare> _FIter max_element(_FIter, _FIter, _Compare, __gnu_parallel::_Parallelism); template<typename _FIter, typename _Compare, typename _IterTag> _FIter __max_element_switch(_FIter, _FIter, _Compare, _IterTag); template<typename _RAIter, typename _Compare> _RAIter __max_element_switch( _RAIter, _RAIter, _Compare, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism = __gnu_parallel::parallel_balanced); template<typename _IIter1, typename _IIter2, typename _OIter> _OIter merge(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2, typename _OIter, typename _Compare> _OIter merge(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, _Compare, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2, typename _OIter, typename _Compare> _OIter merge(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, _Compare); template<typename _IIter1, typename _IIter2, typename _OIter> _OIter merge(_IIter1, _IIter1, _IIter2, _IIter2, _OIter); template<typename _IIter1, typename _IIter2, typename _OIter, typename _Compare, typename _IterTag1, typename _IterTag2, typename _IterTag3> _OIter __merge_switch(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, _Compare, _IterTag1, _IterTag2, _IterTag3); template<typename _IIter1, typename _IIter2, typename _OIter, typename _Compare> _OIter __merge_switch(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, _Compare, random_access_iterator_tag, random_access_iterator_tag, random_access_iterator_tag); template<typename _FIter> _FIter min_element(_FIter, _FIter); template<typename _FIter> _FIter min_element(_FIter, _FIter, __gnu_parallel::sequential_tag); template<typename _FIter> _FIter min_element(_FIter, _FIter, __gnu_parallel::_Parallelism __parallelism_tag); template<typename _FIter, typename _Compare> _FIter min_element(_FIter, _FIter, _Compare); template<typename _FIter, typename _Compare> _FIter min_element(_FIter, _FIter, _Compare, __gnu_parallel::sequential_tag); template<typename _FIter, typename _Compare> _FIter min_element(_FIter, _FIter, _Compare, __gnu_parallel::_Parallelism); template<typename _FIter, typename _Compare, typename _IterTag> _FIter __min_element_switch(_FIter, _FIter, _Compare, _IterTag); template<typename _RAIter, typename _Compare> _RAIter __min_element_switch( _RAIter, _RAIter, _Compare, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism = __gnu_parallel::parallel_balanced); template<typename _RAIter> void nth_element(_RAIter, _RAIter, _RAIter, __gnu_parallel::sequential_tag); template<typename _RAIter, typename _Compare> void nth_element(_RAIter, _RAIter, _RAIter, _Compare, __gnu_parallel::sequential_tag); template<typename _RAIter, typename _Compare> void nth_element(_RAIter, _RAIter, _RAIter, _Compare); template<typename _RAIter> void nth_element(_RAIter, _RAIter, _RAIter); template<typename _RAIter, typename _Compare> void partial_sort(_RAIter, _RAIter, _RAIter, _Compare, __gnu_parallel::sequential_tag); template<typename _RAIter> void partial_sort(_RAIter, _RAIter, _RAIter, __gnu_parallel::sequential_tag); template<typename _RAIter, typename _Compare> void partial_sort(_RAIter, _RAIter, _RAIter, _Compare); template<typename _RAIter> void partial_sort(_RAIter, _RAIter, _RAIter); template<typename _FIter, typename _Predicate> _FIter partition(_FIter, _FIter, _Predicate, __gnu_parallel::sequential_tag); template<typename _FIter, typename _Predicate> _FIter partition(_FIter, _FIter, _Predicate); template<typename _FIter, typename _Predicate, typename _IterTag> _FIter __partition_switch(_FIter, _FIter, _Predicate, _IterTag); template<typename _RAIter, typename _Predicate> _RAIter __partition_switch( _RAIter, _RAIter, _Predicate, random_access_iterator_tag); template<typename _RAIter> void random_shuffle(_RAIter, _RAIter, __gnu_parallel::sequential_tag); template<typename _RAIter, typename _RandomNumberGenerator> void random_shuffle(_RAIter, _RAIter, _RandomNumberGenerator&, __gnu_parallel::sequential_tag); template<typename _RAIter> void random_shuffle(_RAIter, _RAIter); template<typename _RAIter, typename _RandomNumberGenerator> void random_shuffle(_RAIter, _RAIter, #if __cplusplus >= 201103L _RandomNumberGenerator&&); #else _RandomNumberGenerator&); #endif template<typename _IIter1, typename _IIter2, typename _OIter> _OIter set_union(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2, typename _OIter, typename _Predicate> _OIter set_union(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, _Predicate, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2, typename _OIter> _OIter set_union(_IIter1, _IIter1, _IIter2, _IIter2, _OIter); template<typename _IIter1, typename _IIter2, typename _OIter, typename _Predicate> _OIter set_union(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, _Predicate); template<typename _IIter1, typename _IIter2, typename _Predicate, typename _OIter, typename _IterTag1, typename _IterTag2, typename _IterTag3> _OIter __set_union_switch(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, _Predicate, _IterTag1, _IterTag2, _IterTag3); template<typename _RAIter1, typename _RAIter2, typename _Output_RAIter, typename _Predicate> _Output_RAIter __set_union_switch(_RAIter1, _RAIter1, _RAIter2, _RAIter2, _Output_RAIter, _Predicate, random_access_iterator_tag, random_access_iterator_tag, random_access_iterator_tag); template<typename _IIter1, typename _IIter2, typename _OIter> _OIter set_intersection(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2, typename _OIter, typename _Predicate> _OIter set_intersection(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, _Predicate, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2, typename _OIter> _OIter set_intersection(_IIter1, _IIter1, _IIter2, _IIter2, _OIter); template<typename _IIter1, typename _IIter2, typename _OIter, typename _Predicate> _OIter set_intersection(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, _Predicate); template<typename _IIter1, typename _IIter2, typename _Predicate, typename _OIter, typename _IterTag1, typename _IterTag2, typename _IterTag3> _OIter __set_intersection_switch(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, _Predicate, _IterTag1, _IterTag2, _IterTag3); template<typename _RAIter1, typename _RAIter2, typename _Output_RAIter, typename _Predicate> _Output_RAIter __set_intersection_switch(_RAIter1, _RAIter1, _RAIter2, _RAIter2, _Output_RAIter, _Predicate, random_access_iterator_tag, random_access_iterator_tag, random_access_iterator_tag); template<typename _IIter1, typename _IIter2, typename _OIter> _OIter set_symmetric_difference(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2, typename _OIter, typename _Predicate> _OIter set_symmetric_difference(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, _Predicate, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2, typename _OIter> _OIter set_symmetric_difference(_IIter1, _IIter1, _IIter2, _IIter2, _OIter); template<typename _IIter1, typename _IIter2, typename _OIter, typename _Predicate> _OIter set_symmetric_difference(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, _Predicate); template<typename _IIter1, typename _IIter2, typename _Predicate, typename _OIter, typename _IterTag1, typename _IterTag2, typename _IterTag3> _OIter __set_symmetric_difference_switch(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, _Predicate, _IterTag1, _IterTag2, _IterTag3); template<typename _RAIter1, typename _RAIter2, typename _Output_RAIter, typename _Predicate> _Output_RAIter __set_symmetric_difference_switch(_RAIter1, _RAIter1, _RAIter2, _RAIter2, _Output_RAIter, _Predicate, random_access_iterator_tag, random_access_iterator_tag, random_access_iterator_tag); template<typename _IIter1, typename _IIter2, typename _OIter> _OIter set_difference(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2, typename _OIter, typename _Predicate> _OIter set_difference(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, _Predicate, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2, typename _OIter> _OIter set_difference(_IIter1, _IIter1, _IIter2, _IIter2, _OIter); template<typename _IIter1, typename _IIter2, typename _OIter, typename _Predicate> _OIter set_difference(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, _Predicate); template<typename _IIter1, typename _IIter2, typename _Predicate, typename _OIter, typename _IterTag1, typename _IterTag2, typename _IterTag3> _OIter __set_difference_switch(_IIter1, _IIter1, _IIter2, _IIter2, _OIter, _Predicate, _IterTag1, _IterTag2, _IterTag3); template<typename _RAIter1, typename _RAIter2, typename _Output_RAIter, typename _Predicate> _Output_RAIter __set_difference_switch(_RAIter1, _RAIter1, _RAIter2, _RAIter2, _Output_RAIter, _Predicate, random_access_iterator_tag, random_access_iterator_tag, random_access_iterator_tag); template<typename _RAIter> void sort(_RAIter, _RAIter, __gnu_parallel::sequential_tag); template<typename _RAIter, typename _Compare> void sort(_RAIter, _RAIter, _Compare, __gnu_parallel::sequential_tag); template<typename _RAIter> void sort(_RAIter, _RAIter); template<typename _RAIter, typename _Compare> void sort(_RAIter, _RAIter, _Compare); template<typename _RAIter> void stable_sort(_RAIter, _RAIter, __gnu_parallel::sequential_tag); template<typename _RAIter, typename _Compare> void stable_sort(_RAIter, _RAIter, _Compare, __gnu_parallel::sequential_tag); template<typename _RAIter> void stable_sort(_RAIter, _RAIter); template<typename _RAIter, typename _Compare> void stable_sort(_RAIter, _RAIter, _Compare); template<typename _IIter, typename _OIter> _OIter unique_copy(_IIter, _IIter, _OIter, __gnu_parallel::sequential_tag); template<typename _IIter, typename _OIter, typename _Predicate> _OIter unique_copy(_IIter, _IIter, _OIter, _Predicate, __gnu_parallel::sequential_tag); template<typename _IIter, typename _OIter> _OIter unique_copy(_IIter, _IIter, _OIter); template<typename _IIter, typename _OIter, typename _Predicate> _OIter unique_copy(_IIter, _IIter, _OIter, _Predicate); template<typename _IIter, typename _OIter, typename _Predicate, typename _IterTag1, typename _IterTag2> _OIter __unique_copy_switch(_IIter, _IIter, _OIter, _Predicate, _IterTag1, _IterTag2); template<typename _RAIter, typename _RandomAccess_OIter, typename _Predicate> _RandomAccess_OIter __unique_copy_switch(_RAIter, _RAIter, _RandomAccess_OIter, _Predicate, random_access_iterator_tag, random_access_iterator_tag); } // end namespace __parallel } // end namespace std #endif / _GLIBCXX_PARALLEL_ALGORITHMFWD_H */	31.55 KB	2025-09-15 15:41
📄 balanced_quicksort.h // -- C++ -- // Copyright (C) 2007-2021 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/balanced_quicksort.h * @brief Implementation of a dynamically load-balanced parallel quicksort. * * It works in-place and needs only logarithmic extra memory. * The algorithm is similar to the one proposed in * * P. Tsigas and Y. Zhang. * A simple, fast parallel implementation of quicksort and * its performance evaluation on SUN enterprise 10000. * In 11th Euromicro Conference on Parallel, Distributed and * Network-Based Processing, page 372, 2003. * * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_BALANCED_QUICKSORT_H #define _GLIBCXX_PARALLEL_BALANCED_QUICKSORT_H 1 #include <parallel/basic_iterator.h> #include <bits/stl_algo.h> #include <bits/stl_function.h> #include <parallel/settings.h> #include <parallel/partition.h> #include <parallel/random_number.h> #include <parallel/queue.h> #if _GLIBCXX_PARALLEL_ASSERTIONS #include <parallel/checkers.h> #ifdef _GLIBCXX_HAVE_UNISTD_H #include <unistd.h> #endif #endif namespace __gnu_parallel { /* @brief Information local to one thread in the parallel quicksort run. / template<typename _RAIter> struct _QSBThreadLocal { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::difference_type _DifferenceType; /* @brief Continuous part of the sequence, described by an iterator pair. / typedef std::pair<_RAIter, _RAIter> _Piece; /* @brief Initial piece to work on. / _Piece _M_initial; /* @brief Work-stealing queue. / _RestrictedBoundedConcurrentQueue<_Piece> _M_leftover_parts; /* @brief Number of threads involved in this algorithm. / _ThreadIndex _M_num_threads; /* @brief Pointer to a counter of elements left over to sort. / volatile _DifferenceType _M_elements_leftover; /** @brief The complete sequence to sort. / _Piece _M_global; /* @brief Constructor. * @param __queue_size size of the work-stealing queue. / _QSBThreadLocal(int __queue_size) : _M_leftover_parts(__queue_size) { } }; /* @brief Balanced quicksort divide step. * @param __begin Begin iterator of subsequence. * @param __end End iterator of subsequence. * @param __comp Comparator. * @param __num_threads Number of threads that are allowed to work on * this part. * @pre @c (__end-__begin)>=1 / template<typename _RAIter, typename _Compare> typename std::iterator_traits<_RAIter>::difference_type __qsb_divide(_RAIter __begin, _RAIter __end, _Compare __comp, _ThreadIndex __num_threads) { _GLIBCXX_PARALLEL_ASSERT(__num_threads > 0); typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; _RAIter __pivot_pos = __median_of_three_iterators(__begin, __begin + (__end - __begin) / 2, __end - 1, __comp); #if defined(_GLIBCXX_PARALLEL_ASSERTIONS) // Must be in between somewhere. _DifferenceType __n = __end - __begin; _GLIBCXX_PARALLEL_ASSERT((!__comp(__pivot_pos, __begin) && !__comp((__begin + __n / 2), __pivot_pos)) \|\| (!__comp(__pivot_pos, __begin) && !__comp((__end - 1), __pivot_pos)) \|\| (!__comp(__pivot_pos, (__begin + __n / 2)) && !__comp(__begin, __pivot_pos)) \|\| (!__comp(__pivot_pos, (__begin + __n / 2)) && !__comp((__end - 1), __pivot_pos)) \|\| (!__comp(__pivot_pos, (__end - 1)) && !__comp(__begin, __pivot_pos)) \|\| (!__comp(__pivot_pos, (__end - 1)) && !__comp((__begin + __n / 2), __pivot_pos))); #endif // Swap pivot value to end. if (__pivot_pos != (__end - 1)) std::iter_swap(__pivot_pos, __end - 1); __pivot_pos = __end - 1; __gnu_parallel::__binder2nd<_Compare, _ValueType, _ValueType, bool> __pred(__comp, __pivot_pos); // Divide, returning __end - __begin - 1 in the worst case. _DifferenceType __split_pos = __parallel_partition(__begin, __end - 1, __pred, __num_threads); // Swap back pivot to middle. std::iter_swap(__begin + __split_pos, __pivot_pos); __pivot_pos = __begin + __split_pos; #if _GLIBCXX_PARALLEL_ASSERTIONS _RAIter __r; for (__r = __begin; __r != __pivot_pos; ++__r) _GLIBCXX_PARALLEL_ASSERT(__comp(__r, __pivot_pos)); for (; __r != __end; ++__r) _GLIBCXX_PARALLEL_ASSERT(!__comp(__r, __pivot_pos)); #endif return __split_pos; } /** @brief Quicksort conquer step. * @param __tls Array of thread-local storages. * @param __begin Begin iterator of subsequence. * @param __end End iterator of subsequence. * @param __comp Comparator. * @param __iam Number of the thread processing this function. * @param __num_threads * Number of threads that are allowed to work on this part. / template<typename _RAIter, typename _Compare> void __qsb_conquer(_QSBThreadLocal<_RAIter>* __tls, _RAIter __begin, _RAIter __end, _Compare __comp, _ThreadIndex __iam, _ThreadIndex __num_threads, bool __parent_wait) { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; _DifferenceType __n = __end - __begin; if (__num_threads <= 1 \|\| __n <= 1) { __tls[__iam]->_M_initial.first = __begin; __tls[__iam]->_M_initial.second = __end; __qsb_local_sort_with_helping(__tls, __comp, __iam, __parent_wait); return; } // Divide step. _DifferenceType __split_pos = __qsb_divide(__begin, __end, __comp, __num_threads); #if _GLIBCXX_PARALLEL_ASSERTIONS _GLIBCXX_PARALLEL_ASSERT(0 <= __split_pos && __split_pos < (__end - __begin)); #endif _ThreadIndex __num_threads_leftside = std::max<_ThreadIndex> (1, std::min<_ThreadIndex>(__num_threads - 1, __split_pos * __num_threads / __n)); # pragma omp atomic __tls[__iam]->_M_elements_leftover -= (_DifferenceType)1; // Conquer step. # pragma omp parallel num_threads(2) { bool __wait; if(omp_get_num_threads() < 2) __wait = false; else __wait = __parent_wait; # pragma omp sections { # pragma omp section { __qsb_conquer(__tls, __begin, __begin + __split_pos, __comp, __iam, __num_threads_leftside, __wait); __wait = __parent_wait; } // The pivot_pos is left in place, to ensure termination. # pragma omp section { __qsb_conquer(__tls, __begin + __split_pos + 1, __end, __comp, __iam + __num_threads_leftside, __num_threads - __num_threads_leftside, __wait); __wait = __parent_wait; } } } } /* * @brief Quicksort step doing load-balanced local sort. * @param __tls Array of thread-local storages. * @param __comp Comparator. * @param __iam Number of the thread processing this function. / template<typename _RAIter, typename _Compare> void __qsb_local_sort_with_helping(_QSBThreadLocal<_RAIter>* __tls, _Compare& __comp, _ThreadIndex __iam, bool __wait) { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; typedef std::pair<_RAIter, _RAIter> _Piece; _QSBThreadLocal<_RAIter>& __tl = __tls[__iam]; _DifferenceType __base_case_n = _Settings::get().sort_qsb_base_case_maximal_n; if (__base_case_n < 2) __base_case_n = 2; _ThreadIndex __num_threads = __tl._M_num_threads; // Every thread has its own random number generator. _RandomNumber __rng(__iam + 1); _Piece __current = __tl._M_initial; _DifferenceType __elements_done = 0; #if _GLIBCXX_PARALLEL_ASSERTIONS _DifferenceType __total_elements_done = 0; #endif for (;;) { // Invariant: __current must be a valid (maybe empty) range. _RAIter __begin = __current.first, __end = __current.second; _DifferenceType __n = __end - __begin; if (__n > __base_case_n) { // Divide. _RAIter __pivot_pos = __begin + __rng(__n); // Swap __pivot_pos value to end. if (__pivot_pos != (__end - 1)) std::iter_swap(__pivot_pos, __end - 1); __pivot_pos = __end - 1; __gnu_parallel::__binder2nd <_Compare, _ValueType, _ValueType, bool> __pred(__comp, __pivot_pos); // Divide, leave pivot unchanged in last place. _RAIter __split_pos1, __split_pos2; __split_pos1 = __gnu_sequential::partition(__begin, __end - 1, __pred); // Left side: < __pivot_pos; __right side: >= __pivot_pos. #if _GLIBCXX_PARALLEL_ASSERTIONS _GLIBCXX_PARALLEL_ASSERT(__begin <= __split_pos1 && __split_pos1 < __end); #endif // Swap pivot back to middle. if (__split_pos1 != __pivot_pos) std::iter_swap(__split_pos1, __pivot_pos); __pivot_pos = __split_pos1; // In case all elements are equal, __split_pos1 == 0. if ((__split_pos1 + 1 - __begin) < (__n >> 7) \|\| (__end - __split_pos1) < (__n >> 7)) { // Very unequal split, one part smaller than one 128th // elements not strictly larger than the pivot. __gnu_parallel::__unary_negate<__gnu_parallel::__binder1st <_Compare, _ValueType, _ValueType, bool>, _ValueType> __pred(__gnu_parallel::__binder1st <_Compare, _ValueType, _ValueType, bool> (__comp, __pivot_pos)); // Find other end of pivot-equal range. __split_pos2 = __gnu_sequential::partition(__split_pos1 + 1, __end, __pred); } else // Only skip the pivot. __split_pos2 = __split_pos1 + 1; // Elements equal to pivot are done. __elements_done += (__split_pos2 - __split_pos1); #if _GLIBCXX_PARALLEL_ASSERTIONS __total_elements_done += (__split_pos2 - __split_pos1); #endif // Always push larger part onto stack. if (((__split_pos1 + 1) - __begin) < (__end - (__split_pos2))) { // Right side larger. if ((__split_pos2) != __end) __tl._M_leftover_parts.push_front (std::make_pair(__split_pos2, __end)); //__current.first = __begin; //already set anyway __current.second = __split_pos1; continue; } else { // Left side larger. if (__begin != __split_pos1) __tl._M_leftover_parts.push_front(std::make_pair (__begin, __split_pos1)); __current.first = __split_pos2; //__current.second = __end; //already set anyway continue; } } else { __gnu_sequential::sort(__begin, __end, __comp); __elements_done += __n; #if _GLIBCXX_PARALLEL_ASSERTIONS __total_elements_done += __n; #endif // Prefer own stack, small pieces. if (__tl._M_leftover_parts.pop_front(__current)) continue; # pragma omp atomic __tl._M_elements_leftover -= __elements_done; __elements_done = 0; #if _GLIBCXX_PARALLEL_ASSERTIONS double __search_start = omp_get_wtime(); #endif // Look for new work. bool __successfully_stolen = false; while (__wait && __tl._M_elements_leftover > 0 && !__successfully_stolen #if _GLIBCXX_PARALLEL_ASSERTIONS // Possible dead-lock. && (omp_get_wtime() < (__search_start + 1.0)) #endif ) { _ThreadIndex __victim; __victim = __rng(__num_threads); // Large pieces. __successfully_stolen = (__victim != __iam) && __tls[__victim]->_M_leftover_parts.pop_back(__current); if (!__successfully_stolen) __yield(); #if !defined(__ICC) && !defined(__ECC) # pragma omp flush #endif } #if _GLIBCXX_PARALLEL_ASSERTIONS if (omp_get_wtime() >= (__search_start + 1.0)) { sleep(1); _GLIBCXX_PARALLEL_ASSERT(omp_get_wtime() < (__search_start + 1.0)); } #endif if (!__successfully_stolen) { #if _GLIBCXX_PARALLEL_ASSERTIONS _GLIBCXX_PARALLEL_ASSERT(__tl._M_elements_leftover == 0); #endif return; } } } } /** @brief Top-level quicksort routine. * @param __begin Begin iterator of sequence. * @param __end End iterator of sequence. * @param __comp Comparator. * @param __num_threads Number of threads that are allowed to work on * this part. / template<typename _RAIter, typename _Compare> void __parallel_sort_qsb(_RAIter __begin, _RAIter __end, _Compare __comp, _ThreadIndex __num_threads) { _GLIBCXX_CALL(__end - __begin) typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; typedef std::pair<_RAIter, _RAIter> _Piece; typedef _QSBThreadLocal<_RAIter> _TLSType; _DifferenceType __n = __end - __begin; if (__n <= 1) return; // At least one element per processor. if (__num_threads > __n) __num_threads = static_cast<_ThreadIndex>(__n); // Initialize thread local storage _TLSType* __tls = new _TLSType[__num_threads]; _DifferenceType __queue_size = (__num_threads (_ThreadIndex)(__rd_log2(__n) + 1)); for (_ThreadIndex __t = 0; __t < __num_threads; ++__t) __tls[__t] = new _QSBThreadLocal<_RAIter>(__queue_size); // There can never be more than ceil(__rd_log2(__n)) ranges on the // stack, because // 1. Only one processor pushes onto the stack // 2. The largest range has at most length __n // 3. Each range is larger than half of the range remaining volatile _DifferenceType __elements_leftover = __n; for (_ThreadIndex __i = 0; __i < __num_threads; ++__i) { __tls[__i]->_M_elements_leftover = &__elements_leftover; __tls[__i]->_M_num_threads = __num_threads; __tls[__i]->_M_global = std::make_pair(__begin, __end); // Just in case nothing is left to assign. __tls[__i]->_M_initial = std::make_pair(__end, __end); } // Main recursion call. __qsb_conquer(__tls, __begin, __begin + __n, __comp, 0, __num_threads, true); #if _GLIBCXX_PARALLEL_ASSERTIONS // All stack must be empty. _Piece __dummy; for (_ThreadIndex __i = 1; __i < __num_threads; ++__i) _GLIBCXX_PARALLEL_ASSERT( !__tls[__i]->_M_leftover_parts.pop_back(__dummy)); #endif for (_ThreadIndex __i = 0; __i < __num_threads; ++__i) delete __tls[__i]; delete[] __tls; } } // namespace __gnu_parallel #endif /* _GLIBCXX_PARALLEL_BALANCED_QUICKSORT_H */	16.55 KB	2025-09-15 15:41
📄 base.h // -- C++ -- // Copyright (C) 2007-2021 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/base.h * @brief Sequential helper functions. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_BASE_H #define _GLIBCXX_PARALLEL_BASE_H 1 #include <bits/c++config.h> #include <bits/stl_function.h> #include <omp.h> #include <parallel/features.h> #include <parallel/basic_iterator.h> #include <parallel/parallel.h> // Parallel mode namespaces. /* * @namespace std::__parallel * @brief GNU parallel code, replaces standard behavior with parallel behavior. / namespace std _GLIBCXX_VISIBILITY(default) { namespace __parallel { } } /* * @namespace __gnu_parallel * @brief GNU parallel code for public use. / namespace __gnu_parallel { // Import all the parallel versions of components in namespace std. using namespace std::__parallel; } /* * @namespace __gnu_sequential * @brief GNU sequential classes for public use. / namespace __gnu_sequential { // Import whatever is the serial version. #ifdef _GLIBCXX_PARALLEL using namespace std::_GLIBCXX_STD_A; #else using namespace std; #endif } namespace __gnu_parallel { // NB: Including this file cannot produce (unresolved) symbols from // the OpenMP runtime unless the parallel mode is actually invoked // and active, which imples that the OpenMP runtime is actually // going to be linked in. inline _ThreadIndex __get_max_threads() { _ThreadIndex __i = omp_get_max_threads(); return __i > 1 ? __i : 1; } inline bool __is_parallel(const _Parallelism __p) { return __p != sequential; } /* @brief Calculates the rounded-down logarithm of @c __n for base 2. * @param __n Argument. * @return Returns 0 for any argument <1. / template<typename _Size> inline _Size __rd_log2(_Size __n) { _Size __k; for (__k = 0; __n > 1; __n >>= 1) ++__k; return __k; } /* @brief Encode two integers into one gnu_parallel::_CASable. * @param __a First integer, to be encoded in the most-significant @c * _CASable_bits/2 bits. * @param __b Second integer, to be encoded in the least-significant * @c _CASable_bits/2 bits. * @return value encoding @c __a and @c __b. * @see __decode2 / inline _CASable __encode2(int __a, int __b) //must all be non-negative, actually { return (((_CASable)__a) << (_CASable_bits / 2)) \| (((_CASable)__b) << 0); } /* @brief Decode two integers from one gnu_parallel::_CASable. * @param __x __gnu_parallel::_CASable to decode integers from. * @param __a First integer, to be decoded from the most-significant * @c _CASable_bits/2 bits of @c __x. * @param __b Second integer, to be encoded in the least-significant * @c _CASable_bits/2 bits of @c __x. * @see __encode2 / inline void __decode2(_CASable __x, int& __a, int& __b) { __a = (int)((__x >> (_CASable_bits / 2)) & _CASable_mask); __b = (int)((__x >> 0 ) & _CASable_mask); } //needed for parallel "numeric", even if "algorithm" not included /* @brief Equivalent to std::min. / template<typename _Tp> inline const _Tp& min(const _Tp& __a, const _Tp& __b) { return (__a < __b) ? __a : __b; } /* @brief Equivalent to std::max. / template<typename _Tp> inline const _Tp& max(const _Tp& __a, const _Tp& __b) { return (__a > __b) ? __a : __b; } /* @brief Constructs predicate for equality from strict weak * ordering predicate / template<typename _T1, typename _T2, typename _Compare> class _EqualFromLess : public std::binary_function<_T1, _T2, bool> { private: _Compare& _M_comp; public: _EqualFromLess(_Compare& __comp) : _M_comp(__comp) { } bool operator()(const _T1& __a, const _T2& __b) { return !_M_comp(__a, __b) && !_M_comp(__b, __a); } }; /* @brief Similar to std::unary_negate, * but giving the argument types explicitly. / template<typename _Predicate, typename argument_type> class __unary_negate : public std::unary_function<argument_type, bool> { protected: _Predicate _M_pred; public: explicit __unary_negate(const _Predicate& __x) : _M_pred(__x) { } bool operator()(const argument_type& __x) { return !_M_pred(__x); } }; /* @brief Similar to std::binder1st, * but giving the argument types explicitly. / template<typename _Operation, typename _FirstArgumentType, typename _SecondArgumentType, typename _ResultType> class __binder1st : public std::unary_function<_SecondArgumentType, _ResultType> { protected: _Operation _M_op; _FirstArgumentType _M_value; public: __binder1st(const _Operation& __x, const _FirstArgumentType& __y) : _M_op(__x), _M_value(__y) { } _ResultType operator()(const _SecondArgumentType& __x) { return _M_op(_M_value, __x); } // _GLIBCXX_RESOLVE_LIB_DEFECTS // 109. Missing binders for non-const sequence elements _ResultType operator()(_SecondArgumentType& __x) const { return _M_op(_M_value, __x); } }; /* * @brief Similar to std::binder2nd, but giving the argument types * explicitly. / template<typename _Operation, typename _FirstArgumentType, typename _SecondArgumentType, typename _ResultType> class __binder2nd : public std::unary_function<_FirstArgumentType, _ResultType> { protected: _Operation _M_op; _SecondArgumentType _M_value; public: __binder2nd(const _Operation& __x, const _SecondArgumentType& __y) : _M_op(__x), _M_value(__y) { } _ResultType operator()(const _FirstArgumentType& __x) const { return _M_op(__x, _M_value); } // _GLIBCXX_RESOLVE_LIB_DEFECTS // 109. Missing binders for non-const sequence elements _ResultType operator()(_FirstArgumentType& __x) { return _M_op(__x, _M_value); } }; /* @brief Similar to std::equal_to, but allows two different types. / template<typename _T1, typename _T2> struct _EqualTo : std::binary_function<_T1, _T2, bool> { bool operator()(const _T1& __t1, const _T2& __t2) const { return __t1 == __t2; } }; /* @brief Similar to std::less, but allows two different types. / template<typename _T1, typename _T2> struct _Less : std::binary_function<_T1, _T2, bool> { bool operator()(const _T1& __t1, const _T2& __t2) const { return __t1 < __t2; } bool operator()(const _T2& __t2, const _T1& __t1) const { return __t2 < __t1; } }; // Partial specialization for one type. Same as std::less. template<typename _Tp> struct _Less<_Tp, _Tp> : public std::less<_Tp> { }; /* @brief Similar to std::plus, but allows two different types. / template<typename _Tp1, typename _Tp2, typename _Result = __typeof__(static_cast<_Tp1>(0) + static_cast<_Tp2>(0))> struct _Plus : public std::binary_function<_Tp1, _Tp2, _Result> { _Result operator()(const _Tp1& __x, const _Tp2& __y) const { return __x + __y; } }; // Partial specialization for one type. Same as std::plus. template<typename _Tp> struct _Plus<_Tp, _Tp, _Tp> : public std::plus<_Tp> { }; /* @brief Similar to std::multiplies, but allows two different types. / template<typename _Tp1, typename _Tp2, typename _Result = __typeof__(static_cast<_Tp1>(0) static_cast<_Tp2>(0))> struct _Multiplies : public std::binary_function<_Tp1, _Tp2, _Result> { _Result operator()(const _Tp1& __x, const _Tp2& __y) const { return __x * __y; } }; // Partial specialization for one type. Same as std::multiplies. template<typename _Tp> struct _Multiplies<_Tp, _Tp, _Tp> : public std::multiplies<_Tp> { }; /** @brief _Iterator associated with __gnu_parallel::_PseudoSequence. * If features the usual random-access iterator functionality. * @param _Tp Sequence _M_value type. * @param _DifferenceTp Sequence difference type. / template<typename _Tp, typename _DifferenceTp> class _PseudoSequenceIterator { public: typedef _DifferenceTp _DifferenceType; _PseudoSequenceIterator(const _Tp& __val, _DifferenceType __pos) : _M_val(__val), _M_pos(__pos) { } // Pre-increment operator. _PseudoSequenceIterator& operator++() { ++_M_pos; return this; } // Post-increment operator. _PseudoSequenceIterator operator++(int) { return _PseudoSequenceIterator(_M_pos++); } const _Tp& operator() const { return _M_val; } const _Tp& operator[](_DifferenceType) const { return _M_val; } bool operator==(const _PseudoSequenceIterator& __i2) { return _M_pos == __i2._M_pos; } bool operator!=(const _PseudoSequenceIterator& __i2) { return _M_pos != __i2._M_pos; } _DifferenceType operator-(const _PseudoSequenceIterator& __i2) { return _M_pos - __i2._M_pos; } private: const _Tp& _M_val; _DifferenceType _M_pos; }; /* @brief Sequence that conceptually consists of multiple copies of the same element. * The copies are not stored explicitly, of course. * @param _Tp Sequence _M_value type. * @param _DifferenceTp Sequence difference type. / template<typename _Tp, typename _DifferenceTp> class _PseudoSequence { public: typedef _DifferenceTp _DifferenceType; // Better cast down to uint64_t, than up to _DifferenceTp. typedef _PseudoSequenceIterator<_Tp, uint64_t> iterator; /* @brief Constructor. * @param __val Element of the sequence. * @param __count Number of (virtual) copies. / _PseudoSequence(const _Tp& __val, _DifferenceType __count) : _M_val(__val), _M_count(__count) { } /* @brief Begin iterator. / iterator begin() const { return iterator(_M_val, 0); } /* @brief End iterator. / iterator end() const { return iterator(_M_val, _M_count); } private: const _Tp& _M_val; _DifferenceType _M_count; }; /* @brief Compute the median of three referenced elements, according to @c __comp. * @param __a First iterator. * @param __b Second iterator. * @param __c Third iterator. * @param __comp Comparator. / template<typename _RAIter, typename _Compare> _RAIter __median_of_three_iterators(_RAIter __a, _RAIter __b, _RAIter __c, _Compare __comp) { if (__comp(__a, __b)) if (__comp(__b, __c)) return __b; else if (__comp(__a, __c)) return __c; else return __a; else { // Just swap __a and __b. if (__comp(__a, __c)) return __a; else if (__comp(__b, __c)) return __c; else return __b; } } #if _GLIBCXX_PARALLEL_ASSERTIONS && defined(__glibcxx_assert_impl) # define _GLIBCXX_PARALLEL_ASSERT(_Condition) \ do { __glibcxx_assert_impl(_Condition); } while (false) #else # define _GLIBCXX_PARALLEL_ASSERT(_Condition) do { } while (false) #endif } //namespace __gnu_parallel #endif / _GLIBCXX_PARALLEL_BASE_H */	12.13 KB	2025-09-15 15:41
📄 basic_iterator.h // -- C++ -- // Copyright (C) 2007-2021 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/basic_iterator.h * @brief Includes the original header files concerned with iterators * except for stream iterators. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_BASIC_ITERATOR_H #define _GLIBCXX_PARALLEL_BASIC_ITERATOR_H 1 #include <bits/c++config.h> #include <bits/stl_iterator_base_types.h> #include <bits/stl_iterator_base_funcs.h> #include <bits/stl_iterator.h> #endif / _GLIBCXX_PARALLEL_BASIC_ITERATOR_H */	1.55 KB	2025-09-15 15:41
📄 checkers.h // -- C++ -- // Copyright (C) 2007-2021 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/checkers.h * @brief Routines for checking the correctness of algorithm results. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_CHECKERS_H #define _GLIBCXX_PARALLEL_CHECKERS_H 1 #include <cstdio> #include <bits/stl_algobase.h> #include <bits/stl_function.h> namespace __gnu_parallel { /* * @brief Check whether @c [__begin, @c __end) is sorted according * to @c __comp. * @param __begin Begin iterator of sequence. * @param __end End iterator of sequence. * @param __comp Comparator. * @return @c true if sorted, @c false otherwise. / template<typename _IIter, typename _Compare> bool __is_sorted(_IIter __begin, _IIter __end, _Compare __comp) { if (__begin == __end) return true; _IIter __current(__begin), __recent(__begin); for (__current++; __current != __end; __current++) { if (__comp(__current, __recent)) { return false; } __recent = __current; } return true; } } #endif / _GLIBCXX_PARALLEL_CHECKERS_H */	2.18 KB	2025-09-15 15:41
📄 compatibility.h // -- C++ -- // Copyright (C) 2007-2021 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/compatibility.h * @brief Compatibility layer, mostly concerned with atomic operations. * * This file is a GNU parallel extension to the Standard C++ Library * and contains implementation details for the library's internal use. / // Written by Felix Putze. #ifndef _GLIBCXX_PARALLEL_COMPATIBILITY_H #define _GLIBCXX_PARALLEL_COMPATIBILITY_H 1 #include <parallel/types.h> #include <parallel/base.h> #if !defined(_WIN32) \|\| defined (__CYGWIN__) #include <sched.h> #endif #ifdef __MINGW32__ // Including <windows.h> will drag in all the windows32 names. Since // that can cause user code portability problems, we just declare the // one needed function here. extern "C" __attribute((dllimport)) void __attribute__((stdcall)) Sleep (unsigned long); #endif namespace __gnu_parallel { template<typename _Tp> inline _Tp __add_omp(volatile _Tp __ptr, _Tp __addend) { int64_t __res; #pragma omp critical { __res = __ptr; (__ptr) += __addend; } return __res; } /** @brief Add a value to a variable, atomically. * * @param __ptr Pointer to a signed integer. * @param __addend Value to add. / template<typename _Tp> inline _Tp __fetch_and_add(volatile _Tp __ptr, _Tp __addend) { if (__atomic_always_lock_free(sizeof(_Tp), __ptr)) return __atomic_fetch_add(__ptr, __addend, __ATOMIC_ACQ_REL); return __add_omp(__ptr, __addend); } template<typename _Tp> inline bool __cas_omp(volatile _Tp* __ptr, _Tp __comparand, _Tp __replacement) { bool __res = false; #pragma omp critical { if (__ptr == __comparand) { __ptr = __replacement; __res = true; } } return __res; } /** @brief Compare-and-swap * * Compare @c __ptr and @c __comparand. If equal, let @c __ptr=__replacement and return @c true, return @c false otherwise. * @param __ptr Pointer to signed integer. * @param __comparand Compare value. * @param __replacement Replacement value. / template<typename _Tp> inline bool __compare_and_swap(volatile _Tp __ptr, _Tp __comparand, _Tp __replacement) { if (__atomic_always_lock_free(sizeof(_Tp), __ptr)) return __atomic_compare_exchange_n(__ptr, &__comparand, __replacement, false, __ATOMIC_ACQ_REL, __ATOMIC_RELAXED); return __cas_omp(__ptr, __comparand, __replacement); } /** @brief Yield control to another thread, without waiting for * the end of the time slice. / inline void __yield() { #if defined (_WIN32) && !defined (__CYGWIN__) Sleep(0); #else sched_yield(); #endif } } // end namespace #endif / _GLIBCXX_PARALLEL_COMPATIBILITY_H */	3.7 KB	2025-09-15 15:41
📄 compiletime_settings.h // -- C++ -- // Copyright (C) 2007-2021 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/compiletime_settings.h * @brief Defines on options concerning debugging and performance, at * compile-time. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #include <cstdio> /* @brief Determine verbosity level of the parallel mode. * Level 1 prints a message each time a parallel-mode function is entered. / #define _GLIBCXX_VERBOSE_LEVEL 0 /* @def _GLIBCXX_CALL * @brief Macro to produce log message when entering a function. * @param __n Input size. * @see _GLIBCXX_VERBOSE_LEVEL / #if (_GLIBCXX_VERBOSE_LEVEL == 0) #define _GLIBCXX_CALL(__n) #endif #if (_GLIBCXX_VERBOSE_LEVEL == 1) #define _GLIBCXX_CALL(__n) \ printf(" %__s:\niam = %d, __n = %ld, __num_threads = %d\n", \ __PRETTY_FUNCTION__, omp_get_thread_num(), (__n), __get_max_threads()); #endif #ifndef _GLIBCXX_SCALE_DOWN_FPU /* @brief Use floating-point scaling instead of modulo for mapping * random numbers to a range. This can be faster on certain CPUs. / #define _GLIBCXX_SCALE_DOWN_FPU 0 #endif #ifndef _GLIBCXX_PARALLEL_ASSERTIONS /* @brief Switch on many _GLIBCXX_PARALLEL_ASSERTions in parallel code. * Should be switched on only locally. / #define _GLIBCXX_PARALLEL_ASSERTIONS (_GLIBCXX_ASSERTIONS+0) #endif #ifndef _GLIBCXX_RANDOM_SHUFFLE_CONSIDER_L1 /* @brief Switch on many _GLIBCXX_PARALLEL_ASSERTions in parallel code. * Consider the size of the L1 cache for * gnu_parallel::__parallel_random_shuffle(). / #define _GLIBCXX_RANDOM_SHUFFLE_CONSIDER_L1 0 #endif #ifndef _GLIBCXX_RANDOM_SHUFFLE_CONSIDER_TLB /* @brief Switch on many _GLIBCXX_PARALLEL_ASSERTions in parallel code. * Consider the size of the TLB for * gnu_parallel::__parallel_random_shuffle(). */ #define _GLIBCXX_RANDOM_SHUFFLE_CONSIDER_TLB 0 #endif	2.8 KB	2025-09-15 15:41
📄 equally_split.h // -- C++ -- // Copyright (C) 2007-2021 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/equally_split.h * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_EQUALLY_SPLIT_H #define _GLIBCXX_PARALLEL_EQUALLY_SPLIT_H 1 namespace __gnu_parallel { /* @brief function to split a sequence into parts of almost equal size. * * The resulting sequence __s of length __num_threads+1 contains the * splitting positions when splitting the range [0,__n) into parts of * almost equal size (plus minus 1). The first entry is 0, the last * one n. There may result empty parts. * @param __n Number of elements * @param __num_threads Number of parts * @param __s Splitters * @returns End of __splitter sequence, i.e. @c __s+__num_threads+1 / template<typename _DifferenceType, typename _OutputIterator> _OutputIterator __equally_split(_DifferenceType __n, _ThreadIndex __num_threads, _OutputIterator __s) { _DifferenceType __chunk_length = __n / __num_threads; _DifferenceType __num_longer_chunks = __n % __num_threads; _DifferenceType __pos = 0; for (_ThreadIndex __i = 0; __i < __num_threads; ++__i) { __s++ = __pos; __pos += ((__i < __num_longer_chunks) ? (__chunk_length + 1) : __chunk_length); } __s++ = __n; return __s; } /* @brief function to split a sequence into parts of almost equal size. * * Returns the position of the splitting point between * thread number __thread_no (included) and * thread number __thread_no+1 (excluded). * @param __n Number of elements * @param __num_threads Number of parts * @param __thread_no Number of threads * @returns splitting point / template<typename _DifferenceType> _DifferenceType __equally_split_point(_DifferenceType __n, _ThreadIndex __num_threads, _ThreadIndex __thread_no) { _DifferenceType __chunk_length = __n / __num_threads; _DifferenceType __num_longer_chunks = __n % __num_threads; if (__thread_no < __num_longer_chunks) return __thread_no (__chunk_length + 1); else return __num_longer_chunks * (__chunk_length + 1) + (__thread_no - __num_longer_chunks) * __chunk_length; } } #endif /* _GLIBCXX_PARALLEL_EQUALLY_SPLIT_H */	3.28 KB	2025-09-15 15:41
📄 features.h // -- C++ -- // Copyright (C) 2007-2021 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/features.h * @brief Defines on whether to include algorithm variants. * * Less variants reduce executable size and compile time. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_FEATURES_H #define _GLIBCXX_PARALLEL_FEATURES_H 1 #ifndef _GLIBCXX_MERGESORT /* @def _GLIBCXX_MERGESORT * @brief Include parallel multi-way mergesort. * @see __gnu_parallel::_Settings::sort_algorithm / #define _GLIBCXX_MERGESORT 1 #endif #ifndef _GLIBCXX_QUICKSORT /* @def _GLIBCXX_QUICKSORT * @brief Include parallel unbalanced quicksort. * @see __gnu_parallel::_Settings::sort_algorithm / #define _GLIBCXX_QUICKSORT 1 #endif #ifndef _GLIBCXX_BAL_QUICKSORT /* @def _GLIBCXX_BAL_QUICKSORT * @brief Include parallel dynamically load-balanced quicksort. * @see __gnu_parallel::_Settings::sort_algorithm / #define _GLIBCXX_BAL_QUICKSORT 1 #endif #ifndef _GLIBCXX_FIND_GROWING_BLOCKS /* @brief Include the growing blocks variant for std::find. * @see __gnu_parallel::_Settings::find_algorithm / #define _GLIBCXX_FIND_GROWING_BLOCKS 1 #endif #ifndef _GLIBCXX_FIND_CONSTANT_SIZE_BLOCKS /* @brief Include the equal-sized blocks variant for std::find. * @see __gnu_parallel::_Settings::find_algorithm / #define _GLIBCXX_FIND_CONSTANT_SIZE_BLOCKS 1 #endif #ifndef _GLIBCXX_FIND_EQUAL_SPLIT /* @def _GLIBCXX_FIND_EQUAL_SPLIT * @brief Include the equal splitting variant for std::find. * @see __gnu_parallel::_Settings::find_algorithm / #define _GLIBCXX_FIND_EQUAL_SPLIT 1 #endif #ifndef _GLIBCXX_TREE_INITIAL_SPLITTING /* @def _GLIBCXX_TREE_INITIAL_SPLITTING * @brief Include the initial splitting variant for * _Rb_tree::insert_unique(_IIter beg, _IIter __end). * @see __gnu_parallel::_Rb_tree / #define _GLIBCXX_TREE_INITIAL_SPLITTING 1 #endif #ifndef _GLIBCXX_TREE_DYNAMIC_BALANCING /* @def _GLIBCXX_TREE_DYNAMIC_BALANCING * @brief Include the dynamic balancing variant for * _Rb_tree::insert_unique(_IIter beg, _IIter __end). * @see __gnu_parallel::_Rb_tree / #define _GLIBCXX_TREE_DYNAMIC_BALANCING 1 #endif #ifndef _GLIBCXX_TREE_FULL_COPY /* @def _GLIBCXX_TREE_FULL_COPY * @brief In order to sort the input sequence of * _Rb_tree::insert_unique(_IIter beg, _IIter __end) a * full copy of the input elements is done. * @see __gnu_parallel::_Rb_tree / #define _GLIBCXX_TREE_FULL_COPY 1 #endif #endif / _GLIBCXX_PARALLEL_FEATURES_H */	3.46 KB	2025-09-15 15:41
📄 find.h // -- C++ -- // Copyright (C) 2007-2021 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/find.h * @brief Parallel implementation base for std::find(), std::equal() * and related functions. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Felix Putze and Johannes Singler. #ifndef _GLIBCXX_PARALLEL_FIND_H #define _GLIBCXX_PARALLEL_FIND_H 1 #include <bits/stl_algobase.h> #include <parallel/features.h> #include <parallel/parallel.h> #include <parallel/compatibility.h> #include <parallel/equally_split.h> namespace __gnu_parallel { /* * @brief Parallel std::find, switch for different algorithms. * @param __begin1 Begin iterator of first sequence. * @param __end1 End iterator of first sequence. * @param __begin2 Begin iterator of second sequence. Must have same * length as first sequence. * @param __pred Find predicate. * @param __selector _Functionality (e. g. std::find_if(), std::equal(),...) * @return Place of finding in both sequences. / template<typename _RAIter1, typename _RAIter2, typename _Pred, typename _Selector> inline std::pair<_RAIter1, _RAIter2> __find_template(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _Pred __pred, _Selector __selector) { switch (_Settings::get().find_algorithm) { case GROWING_BLOCKS: return __find_template(__begin1, __end1, __begin2, __pred, __selector, growing_blocks_tag()); case CONSTANT_SIZE_BLOCKS: return __find_template(__begin1, __end1, __begin2, __pred, __selector, constant_size_blocks_tag()); case EQUAL_SPLIT: return __find_template(__begin1, __end1, __begin2, __pred, __selector, equal_split_tag()); default: _GLIBCXX_PARALLEL_ASSERT(false); return std::make_pair(__begin1, __begin2); } } #if _GLIBCXX_FIND_EQUAL_SPLIT /* * @brief Parallel std::find, equal splitting variant. * @param __begin1 Begin iterator of first sequence. * @param __end1 End iterator of first sequence. * @param __begin2 Begin iterator of second sequence. Second __sequence * must have same length as first sequence. * @param __pred Find predicate. * @param __selector _Functionality (e. g. std::find_if(), std::equal(),...) * @return Place of finding in both sequences. / template<typename _RAIter1, typename _RAIter2, typename _Pred, typename _Selector> std::pair<_RAIter1, _RAIter2> __find_template(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _Pred __pred, _Selector __selector, equal_split_tag) { _GLIBCXX_CALL(__end1 - __begin1) typedef std::iterator_traits<_RAIter1> _TraitsType; typedef typename _TraitsType::difference_type _DifferenceType; typedef typename _TraitsType::value_type _ValueType; _DifferenceType __length = __end1 - __begin1; _DifferenceType __result = __length; _DifferenceType __borders; omp_lock_t __result_lock; omp_init_lock(&__result_lock); _ThreadIndex __num_threads = __get_max_threads(); # pragma omp parallel num_threads(__num_threads) { # pragma omp single { __num_threads = omp_get_num_threads(); __borders = new _DifferenceType[__num_threads + 1]; __equally_split(__length, __num_threads, __borders); } //single _ThreadIndex __iam = omp_get_thread_num(); _DifferenceType __start = __borders[__iam], __stop = __borders[__iam + 1]; _RAIter1 __i1 = __begin1 + __start; _RAIter2 __i2 = __begin2 + __start; for (_DifferenceType __pos = __start; __pos < __stop; ++__pos) { # pragma omp flush(__result) // Result has been set to something lower. if (__result < __pos) break; if (__selector(__i1, __i2, __pred)) { omp_set_lock(&__result_lock); if (__pos < __result) __result = __pos; omp_unset_lock(&__result_lock); break; } ++__i1; ++__i2; } } //parallel omp_destroy_lock(&__result_lock); delete[] __borders; return std::pair<_RAIter1, _RAIter2>(__begin1 + __result, __begin2 + __result); } #endif #if _GLIBCXX_FIND_GROWING_BLOCKS /** * @brief Parallel std::find, growing block size variant. * @param __begin1 Begin iterator of first sequence. * @param __end1 End iterator of first sequence. * @param __begin2 Begin iterator of second sequence. Second __sequence * must have same length as first sequence. * @param __pred Find predicate. * @param __selector _Functionality (e. g. std::find_if(), std::equal(),...) * @return Place of finding in both sequences. * @see __gnu_parallel::_Settings::find_sequential_search_size * @see __gnu_parallel::_Settings::find_scale_factor * * There are two main differences between the growing blocks and * the constant-size blocks variants. * 1. For GB, the block size grows; for CSB, the block size is fixed. * 2. For GB, the blocks are allocated dynamically; * for CSB, the blocks are allocated in a predetermined manner, * namely spacial round-robin. / template<typename _RAIter1, typename _RAIter2, typename _Pred, typename _Selector> std::pair<_RAIter1, _RAIter2> __find_template(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _Pred __pred, _Selector __selector, growing_blocks_tag) { _GLIBCXX_CALL(__end1 - __begin1) typedef std::iterator_traits<_RAIter1> _TraitsType; typedef typename _TraitsType::difference_type _DifferenceType; typedef typename _TraitsType::value_type _ValueType; const _Settings& __s = _Settings::get(); _DifferenceType __length = __end1 - __begin1; _DifferenceType __sequential_search_size = std::min<_DifferenceType> (__length, __s.find_sequential_search_size); // Try it sequentially first. std::pair<_RAIter1, _RAIter2> __find_seq_result = __selector._M_sequential_algorithm (__begin1, __begin1 + __sequential_search_size, __begin2, __pred); if (__find_seq_result.first != (__begin1 + __sequential_search_size)) return __find_seq_result; // Index of beginning of next free block (after sequential find). _DifferenceType __next_block_start = __sequential_search_size; _DifferenceType __result = __length; omp_lock_t __result_lock; omp_init_lock(&__result_lock); const float __scale_factor = __s.find_scale_factor; _ThreadIndex __num_threads = __get_max_threads(); # pragma omp parallel shared(__result) num_threads(__num_threads) { # pragma omp single __num_threads = omp_get_num_threads(); // Not within first __k elements -> start parallel. _ThreadIndex __iam = omp_get_thread_num(); _DifferenceType __block_size = std::max<_DifferenceType>(1, __scale_factor __next_block_start); _DifferenceType __start = __fetch_and_add<_DifferenceType> (&__next_block_start, __block_size); // Get new block, update pointer to next block. _DifferenceType __stop = std::min<_DifferenceType>(__length, __start + __block_size); std::pair<_RAIter1, _RAIter2> __local_result; while (__start < __length) { # pragma omp flush(__result) // Get new value of result. if (__result < __start) { // No chance to find first element. break; } __local_result = __selector._M_sequential_algorithm (__begin1 + __start, __begin1 + __stop, __begin2 + __start, __pred); if (__local_result.first != (__begin1 + __stop)) { omp_set_lock(&__result_lock); if ((__local_result.first - __begin1) < __result) { __result = __local_result.first - __begin1; // Result cannot be in future blocks, stop algorithm. __fetch_and_add<_DifferenceType>(&__next_block_start, __length); } omp_unset_lock(&__result_lock); } _DifferenceType __block_size = std::max<_DifferenceType>(1, __scale_factor * __next_block_start); // Get new block, update pointer to next block. __start = __fetch_and_add<_DifferenceType>(&__next_block_start, __block_size); __stop = std::min<_DifferenceType>(__length, __start + __block_size); } } //parallel omp_destroy_lock(&__result_lock); // Return iterator on found element. return std::pair<_RAIter1, _RAIter2>(__begin1 + __result, __begin2 + __result); } #endif #if _GLIBCXX_FIND_CONSTANT_SIZE_BLOCKS /** * @brief Parallel std::find, constant block size variant. * @param __begin1 Begin iterator of first sequence. * @param __end1 End iterator of first sequence. * @param __begin2 Begin iterator of second sequence. Second __sequence * must have same length as first sequence. * @param __pred Find predicate. * @param __selector _Functionality (e. g. std::find_if(), std::equal(),...) * @return Place of finding in both sequences. * @see __gnu_parallel::_Settings::find_sequential_search_size * @see __gnu_parallel::_Settings::find_block_size * There are two main differences between the growing blocks and the * constant-size blocks variants. * 1. For GB, the block size grows; for CSB, the block size is fixed. * 2. For GB, the blocks are allocated dynamically; for CSB, the * blocks are allocated in a predetermined manner, namely spacial * round-robin. / template<typename _RAIter1, typename _RAIter2, typename _Pred, typename _Selector> std::pair<_RAIter1, _RAIter2> __find_template(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _Pred __pred, _Selector __selector, constant_size_blocks_tag) { _GLIBCXX_CALL(__end1 - __begin1) typedef std::iterator_traits<_RAIter1> _TraitsType; typedef typename _TraitsType::difference_type _DifferenceType; typedef typename _TraitsType::value_type _ValueType; const _Settings& __s = _Settings::get(); _DifferenceType __length = __end1 - __begin1; _DifferenceType __sequential_search_size = std::min<_DifferenceType> (__length, __s.find_sequential_search_size); // Try it sequentially first. std::pair<_RAIter1, _RAIter2> __find_seq_result = __selector._M_sequential_algorithm (__begin1, __begin1 + __sequential_search_size, __begin2, __pred); if (__find_seq_result.first != (__begin1 + __sequential_search_size)) return __find_seq_result; _DifferenceType __result = __length; omp_lock_t __result_lock; omp_init_lock(&__result_lock); // Not within first __sequential_search_size elements -> start parallel. _ThreadIndex __num_threads = __get_max_threads(); # pragma omp parallel shared(__result) num_threads(__num_threads) { # pragma omp single __num_threads = omp_get_num_threads(); _ThreadIndex __iam = omp_get_thread_num(); _DifferenceType __block_size = __s.find_initial_block_size; // First element of thread's current iteration. _DifferenceType __iteration_start = __sequential_search_size; // Where to work (initialization). _DifferenceType __start = __iteration_start + __iam __block_size; _DifferenceType __stop = std::min<_DifferenceType>(__length, __start + __block_size); std::pair<_RAIter1, _RAIter2> __local_result; while (__start < __length) { // Get new value of result. # pragma omp flush(__result) // No chance to find first element. if (__result < __start) break; __local_result = __selector._M_sequential_algorithm (__begin1 + __start, __begin1 + __stop, __begin2 + __start, __pred); if (__local_result.first != (__begin1 + __stop)) { omp_set_lock(&__result_lock); if ((__local_result.first - __begin1) < __result) __result = __local_result.first - __begin1; omp_unset_lock(&__result_lock); // Will not find better value in its interval. break; } __iteration_start += __num_threads * __block_size; // Where to work. __start = __iteration_start + __iam * __block_size; __stop = std::min<_DifferenceType>(__length, __start + __block_size); } } //parallel omp_destroy_lock(&__result_lock); // Return iterator on found element. return std::pair<_RAIter1, _RAIter2>(__begin1 + __result, __begin2 + __result); } #endif } // end namespace #endif /* _GLIBCXX_PARALLEL_FIND_H */	13.27 KB	2025-09-15 15:41
📄 find_selectors.h // -- C++ -- // Copyright (C) 2007-2021 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/find_selectors.h * @brief _Function objects representing different tasks to be plugged * into the parallel find algorithm. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Felix Putze. #ifndef _GLIBCXX_PARALLEL_FIND_SELECTORS_H #define _GLIBCXX_PARALLEL_FIND_SELECTORS_H 1 #include <parallel/tags.h> #include <parallel/basic_iterator.h> #include <bits/stl_pair.h> namespace __gnu_parallel { /* @brief Base class of all __gnu_parallel::__find_template selectors. / struct __generic_find_selector { }; /* * @brief Test predicate on a single element, used for std::find() * and std::find_if (). / struct __find_if_selector : public __generic_find_selector { /* @brief Test on one position. * @param __i1 _Iterator on first sequence. * @param __i2 _Iterator on second sequence (unused). * @param __pred Find predicate. / template<typename _RAIter1, typename _RAIter2, typename _Pred> bool operator()(_RAIter1 __i1, _RAIter2 __i2, _Pred __pred) { return __pred(__i1); } /** @brief Corresponding sequential algorithm on a sequence. * @param __begin1 Begin iterator of first sequence. * @param __end1 End iterator of first sequence. * @param __begin2 Begin iterator of second sequence. * @param __pred Find predicate. / template<typename _RAIter1, typename _RAIter2, typename _Pred> std::pair<_RAIter1, _RAIter2> _M_sequential_algorithm(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _Pred __pred) { return std::make_pair(find_if(__begin1, __end1, __pred, sequential_tag()), __begin2); } }; /* @brief Test predicate on two adjacent elements. / struct __adjacent_find_selector : public __generic_find_selector { /* @brief Test on one position. * @param __i1 _Iterator on first sequence. * @param __i2 _Iterator on second sequence (unused). * @param __pred Find predicate. / template<typename _RAIter1, typename _RAIter2, typename _Pred> bool operator()(_RAIter1 __i1, _RAIter2 __i2, _Pred __pred) { // Passed end iterator is one short. return __pred(__i1, (__i1 + 1)); } /* @brief Corresponding sequential algorithm on a sequence. * @param __begin1 Begin iterator of first sequence. * @param __end1 End iterator of first sequence. * @param __begin2 Begin iterator of second sequence. * @param __pred Find predicate. / template<typename _RAIter1, typename _RAIter2, typename _Pred> std::pair<_RAIter1, _RAIter2> _M_sequential_algorithm(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _Pred __pred) { // Passed end iterator is one short. _RAIter1 __spot = adjacent_find(__begin1, __end1 + 1, __pred, sequential_tag()); if (__spot == (__end1 + 1)) __spot = __end1; return std::make_pair(__spot, __begin2); } }; /* @brief Test inverted predicate on a single element. / struct __mismatch_selector : public __generic_find_selector { /* * @brief Test on one position. * @param __i1 _Iterator on first sequence. * @param __i2 _Iterator on second sequence (unused). * @param __pred Find predicate. / template<typename _RAIter1, typename _RAIter2, typename _Pred> bool operator()(_RAIter1 __i1, _RAIter2 __i2, _Pred __pred) { return !__pred(__i1, __i2); } /* * @brief Corresponding sequential algorithm on a sequence. * @param __begin1 Begin iterator of first sequence. * @param __end1 End iterator of first sequence. * @param __begin2 Begin iterator of second sequence. * @param __pred Find predicate. / template<typename _RAIter1, typename _RAIter2, typename _Pred> std::pair<_RAIter1, _RAIter2> _M_sequential_algorithm(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _Pred __pred) { return mismatch(__begin1, __end1, __begin2, __pred, sequential_tag()); } }; /* @brief Test predicate on several elements. / template<typename _FIterator> struct __find_first_of_selector : public __generic_find_selector { _FIterator _M_begin; _FIterator _M_end; explicit __find_first_of_selector(_FIterator __begin, _FIterator __end) : _M_begin(__begin), _M_end(__end) { } /* @brief Test on one position. * @param __i1 _Iterator on first sequence. * @param __i2 _Iterator on second sequence (unused). * @param __pred Find predicate. / template<typename _RAIter1, typename _RAIter2, typename _Pred> bool operator()(_RAIter1 __i1, _RAIter2 __i2, _Pred __pred) { for (_FIterator __pos_in_candidates = _M_begin; __pos_in_candidates != _M_end; ++__pos_in_candidates) if (__pred(__i1, __pos_in_candidates)) return true; return false; } /* @brief Corresponding sequential algorithm on a sequence. * @param __begin1 Begin iterator of first sequence. * @param __end1 End iterator of first sequence. * @param __begin2 Begin iterator of second sequence. * @param __pred Find predicate. / template<typename _RAIter1, typename _RAIter2, typename _Pred> std::pair<_RAIter1, _RAIter2> _M_sequential_algorithm(_RAIter1 __begin1, _RAIter1 __end1, _RAIter2 __begin2, _Pred __pred) { return std::make_pair(find_first_of(__begin1, __end1, _M_begin, _M_end, __pred, sequential_tag()), __begin2); } }; } #endif / _GLIBCXX_PARALLEL_FIND_SELECTORS_H */	6.83 KB	2025-09-15 15:41
📄 for_each.h // -- C++ -- // Copyright (C) 2007-2021 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/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 */	3.85 KB	2025-09-15 15:41
📄 for_each_selectors.h // -- C++ -- // Copyright (C) 2007-2021 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/for_each_selectors.h * @brief Functors representing different tasks to be plugged into the * generic parallelization methods for embarrassingly parallel functions. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Felix Putze. #ifndef _GLIBCXX_PARALLEL_FOR_EACH_SELECTORS_H #define _GLIBCXX_PARALLEL_FOR_EACH_SELECTORS_H 1 #include <parallel/basic_iterator.h> namespace __gnu_parallel { /* @brief Generic __selector for embarrassingly parallel functions. / template<typename _It> struct __generic_for_each_selector { /* @brief _Iterator on last element processed; needed for some * algorithms (e. g. std::transform()). / _It _M_finish_iterator; }; /* @brief std::for_each() selector. / template<typename _It> struct __for_each_selector : public __generic_for_each_selector<_It> { /* @brief Functor execution. * @param __o Operator. * @param __i iterator referencing object. / template<typename _Op> bool operator()(_Op& __o, _It __i) { __o(__i); return true; } }; /** @brief std::generate() selector. / template<typename _It> struct __generate_selector : public __generic_for_each_selector<_It> { /* @brief Functor execution. * @param __o Operator. * @param __i iterator referencing object. / template<typename _Op> bool operator()(_Op& __o, _It __i) { __i = __o(); return true; } }; /** @brief std::fill() selector. / template<typename _It> struct __fill_selector : public __generic_for_each_selector<_It> { /* @brief Functor execution. * @param __v Current value. * @param __i iterator referencing object. / template<typename _ValueType> bool operator()(_ValueType& __v, _It __i) { __i = __v; return true; } }; /** @brief std::transform() __selector, one input sequence variant. / template<typename _It> struct __transform1_selector : public __generic_for_each_selector<_It> { /* @brief Functor execution. * @param __o Operator. * @param __i iterator referencing object. / template<typename _Op> bool operator()(_Op& __o, _It __i) { __i.second = __o(__i.first); return true; } }; /* @brief std::transform() __selector, two input sequences variant. / template<typename _It> struct __transform2_selector : public __generic_for_each_selector<_It> { /* @brief Functor execution. * @param __o Operator. * @param __i iterator referencing object. / template<typename _Op> bool operator()(_Op& __o, _It __i) { __i._M_third = __o(__i._M_first, __i._M_second); return true; } }; /** @brief std::replace() selector. / template<typename _It, typename _Tp> struct __replace_selector : public __generic_for_each_selector<_It> { /* @brief Value to replace with. / const _Tp& __new_val; /* @brief Constructor * @param __new_val Value to replace with. / explicit __replace_selector(const _Tp &__new_val) : __new_val(__new_val) {} /* @brief Functor execution. * @param __v Current value. * @param __i iterator referencing object. / bool operator()(_Tp& __v, _It __i) { if (__i == __v) __i = __new_val; return true; } }; /* @brief std::replace() selector. / template<typename _It, typename _Op, typename _Tp> struct __replace_if_selector : public __generic_for_each_selector<_It> { /* @brief Value to replace with. / const _Tp& __new_val; /* @brief Constructor. * @param __new_val Value to replace with. / explicit __replace_if_selector(const _Tp &__new_val) : __new_val(__new_val) { } /* @brief Functor execution. * @param __o Operator. * @param __i iterator referencing object. / bool operator()(_Op& __o, _It __i) { if (__o(__i)) __i = __new_val; return true; } }; /* @brief std::count() selector. / template<typename _It, typename _Diff> struct __count_selector : public __generic_for_each_selector<_It> { /* @brief Functor execution. * @param __v Current value. * @param __i iterator referencing object. * @return 1 if count, 0 if does not count. / template<typename _ValueType> _Diff operator()(_ValueType& __v, _It __i) { return (__v == __i) ? 1 : 0; } }; /** @brief std::count_if () selector. / template<typename _It, typename _Diff> struct __count_if_selector : public __generic_for_each_selector<_It> { /* @brief Functor execution. * @param __o Operator. * @param __i iterator referencing object. * @return 1 if count, 0 if does not count. / template<typename _Op> _Diff operator()(_Op& __o, _It __i) { return (__o(__i)) ? 1 : 0; } }; /** @brief std::accumulate() selector. / template<typename _It> struct __accumulate_selector : public __generic_for_each_selector<_It> { /* @brief Functor execution. * @param __o Operator (unused). * @param __i iterator referencing object. * @return The current value. / template<typename _Op> typename std::iterator_traits<_It>::value_type operator()(_Op __o, _It __i) { return __i; } }; /** @brief std::inner_product() selector. / template<typename _It, typename _It2, typename _Tp> struct __inner_product_selector : public __generic_for_each_selector<_It> { /* @brief Begin iterator of first sequence. / _It __begin1_iterator; /* @brief Begin iterator of second sequence. / _It2 __begin2_iterator; /* @brief Constructor. * @param __b1 Begin iterator of first sequence. * @param __b2 Begin iterator of second sequence. / explicit __inner_product_selector(_It __b1, _It2 __b2) : __begin1_iterator(__b1), __begin2_iterator(__b2) { } /* @brief Functor execution. * @param __mult Multiplication functor. * @param __current iterator referencing object. * @return Inner product elemental __result. / template<typename _Op> _Tp operator()(_Op __mult, _It __current) { typename std::iterator_traits<_It>::difference_type __position = __current - __begin1_iterator; return __mult(__current, (__begin2_iterator + __position)); } }; /* @brief Selector that just returns the passed iterator. / template<typename _It> struct __identity_selector : public __generic_for_each_selector<_It> { /* @brief Functor execution. * @param __o Operator (unused). * @param __i iterator referencing object. * @return Passed iterator. / template<typename _Op> _It operator()(_Op __o, _It __i) { return __i; } }; /* @brief Selector that returns the difference between two adjacent * __elements. / template<typename _It> struct __adjacent_difference_selector : public __generic_for_each_selector<_It> { template<typename _Op> bool operator()(_Op& __o, _It __i) { typename _It::first_type __go_back_one = __i.first; --__go_back_one; __i.second = __o(__i.first, __go_back_one); return true; } }; /** @brief Functor doing nothing * * For some __reduction tasks (this is not a function object, but is * passed as __selector __dummy parameter. / struct _Nothing { /* @brief Functor execution. * @param __i iterator referencing object. / template<typename _It> void operator()(_It __i) { } }; /* @brief Reduction function doing nothing. / struct _DummyReduct { bool operator()(bool, bool) const { return true; } }; /* @brief Reduction for finding the maximum element, using a comparator. / template<typename _Compare, typename _It> struct __min_element_reduct { _Compare& __comp; explicit __min_element_reduct(_Compare &__c) : __comp(__c) { } _It operator()(_It __x, _It __y) { return (__comp(__x, __y)) ? __x : __y; } }; /* @brief Reduction for finding the maximum element, using a comparator. / template<typename _Compare, typename _It> struct __max_element_reduct { _Compare& __comp; explicit __max_element_reduct(_Compare& __c) : __comp(__c) { } _It operator()(_It __x, _It __y) { return (__comp(__x, __y)) ? __y : __x; } }; /* @brief General reduction, using a binary operator. / template<typename _BinOp> struct __accumulate_binop_reduct { _BinOp& __binop; explicit __accumulate_binop_reduct(_BinOp& __b) : __binop(__b) { } template<typename _Result, typename _Addend> _Result operator()(const _Result& __x, const _Addend& __y) { return __binop(__x, __y); } }; } #endif / _GLIBCXX_PARALLEL_FOR_EACH_SELECTORS_H */	10.32 KB	2025-09-15 15:41
📄 iterator.h // -- C++ -- // Copyright (C) 2007-2021 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/iterator.h * @brief Helper iterator classes for the std::transform() functions. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_ITERATOR_H #define _GLIBCXX_PARALLEL_ITERATOR_H 1 #include <parallel/basic_iterator.h> #include <bits/stl_pair.h> namespace __gnu_parallel { /* @brief A pair of iterators. The usual iterator operations are * applied to both child iterators. / template<typename _Iterator1, typename _Iterator2, typename _IteratorCategory> class _IteratorPair : public std::pair<_Iterator1, _Iterator2> { private: typedef std::pair<_Iterator1, _Iterator2> _Base; public: typedef _IteratorCategory iterator_category; typedef void value_type; typedef std::iterator_traits<_Iterator1> _TraitsType; typedef typename _TraitsType::difference_type difference_type; typedef _IteratorPair pointer; typedef _IteratorPair& reference; _IteratorPair() { } _IteratorPair(const _Iterator1& __first, const _Iterator2& __second) : _Base(__first, __second) { } // Pre-increment operator. _IteratorPair& operator++() { ++_Base::first; ++_Base::second; return this; } // Post-increment operator. const _IteratorPair operator++(int) { return _IteratorPair(_Base::first++, _Base::second++); } // Pre-decrement operator. _IteratorPair& operator--() { --_Base::first; --_Base::second; return this; } // Post-decrement operator. const _IteratorPair operator--(int) { return _IteratorPair(_Base::first--, _Base::second--); } // Type conversion. operator _Iterator2() const { return _Base::second; } _IteratorPair& operator=(const _IteratorPair& __other) { _Base::first = __other.first; _Base::second = __other.second; return this; } _IteratorPair operator+(difference_type __delta) const { return _IteratorPair(_Base::first + __delta, _Base::second + __delta); } difference_type operator-(const _IteratorPair& __other) const { return _Base::first - __other.first; } }; /* @brief A triple of iterators. The usual iterator operations are applied to all three child iterators. / template<typename _Iterator1, typename _Iterator2, typename _Iterator3, typename _IteratorCategory> class _IteratorTriple { public: typedef _IteratorCategory iterator_category; typedef void value_type; typedef typename std::iterator_traits<_Iterator1>::difference_type difference_type; typedef _IteratorTriple pointer; typedef _IteratorTriple& reference; _Iterator1 _M_first; _Iterator2 _M_second; _Iterator3 _M_third; _IteratorTriple() { } _IteratorTriple(const _Iterator1& __first, const _Iterator2& __second, const _Iterator3& __third) { _M_first = __first; _M_second = __second; _M_third = __third; } // Pre-increment operator. _IteratorTriple& operator++() { ++_M_first; ++_M_second; ++_M_third; return this; } // Post-increment operator. const _IteratorTriple operator++(int) { return _IteratorTriple(_M_first++, _M_second++, _M_third++); } // Pre-decrement operator. _IteratorTriple& operator--() { --_M_first; --_M_second; --_M_third; return this; } // Post-decrement operator. const _IteratorTriple operator--(int) { return _IteratorTriple(_M_first--, _M_second--, _M_third--); } // Type conversion. operator _Iterator3() const { return _M_third; } _IteratorTriple& operator=(const _IteratorTriple& __other) { _M_first = __other._M_first; _M_second = __other._M_second; _M_third = __other._M_third; return this; } _IteratorTriple operator+(difference_type __delta) const { return _IteratorTriple(_M_first + __delta, _M_second + __delta, _M_third + __delta); } difference_type operator-(const _IteratorTriple& __other) const { return _M_first - __other._M_first; } }; } #endif / _GLIBCXX_PARALLEL_ITERATOR_H */	5.54 KB	2025-09-15 15:41
📄 list_partition.h // -- C++ -- // Copyright (C) 2007-2021 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/list_partition.h * @brief _Functionality to split __sequence referenced by only input * iterators. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Leonor Frias Moya and Johannes Singler. #ifndef _GLIBCXX_PARALLEL_LIST_PARTITION_H #define _GLIBCXX_PARALLEL_LIST_PARTITION_H 1 #include <parallel/parallel.h> #include <vector> namespace __gnu_parallel { /* @brief Shrinks and doubles the ranges. * @param __os_starts Start positions worked on (oversampled). * @param __count_to_two Counts up to 2. * @param __range_length Current length of a chunk. * @param __make_twice Whether the @c __os_starts is allowed to be * grown or not / template<typename _IIter> void __shrink_and_double(std::vector<_IIter>& __os_starts, size_t& __count_to_two, size_t& __range_length, const bool __make_twice) { ++__count_to_two; if (!__make_twice \|\| __count_to_two < 2) __shrink(__os_starts, __count_to_two, __range_length); else { __os_starts.resize((__os_starts.size() - 1) 2 + 1); __count_to_two = 0; } } /** @brief Combines two ranges into one and thus halves the number of ranges. * @param __os_starts Start positions worked on (oversampled). * @param __count_to_two Counts up to 2. * @param __range_length Current length of a chunk. / template<typename _IIter> void __shrink(std::vector<_IIter>& __os_starts, size_t& __count_to_two, size_t& __range_length) { for (typename std::vector<_IIter>::size_type __i = 0; __i <= (__os_starts.size() / 2); ++__i) __os_starts[__i] = __os_starts[__i 2]; __range_length = 2; } /* @brief Splits a sequence given by input iterators into parts of * almost equal size * * The function needs only one pass over the sequence. * @param __begin Begin iterator of input sequence. * @param __end End iterator of input sequence. * @param __starts Start iterators for the resulting parts, dimension * @c __num_parts+1. For convenience, @c __starts @c [__num_parts] * contains the end iterator of the sequence. * @param __lengths Length of the resulting parts. * @param __num_parts Number of parts to split the sequence into. * @param __f Functor to be applied to each element by traversing __it * @param __oversampling Oversampling factor. If 0, then the * partitions will differ in at most * \f$\sqrt{\mathrm{end} - \mathrm{begin}}\f$ * elements. Otherwise, the ratio between the * longest and the shortest part is bounded by * \f$1/(\mathrm{oversampling} \cdot \mathrm{num\_parts})\f$ * @return Length of the whole sequence. / template<typename _IIter, typename _FunctorType> size_t list_partition(const _IIter __begin, const _IIter __end, _IIter __starts, size_t* __lengths, const int __num_parts, _FunctorType& __f, int __oversampling = 0) { bool __make_twice = false; // The resizing algorithm is chosen according to the oversampling factor. if (__oversampling == 0) { __make_twice = true; __oversampling = 1; } std::vector<_IIter> __os_starts(2 * __oversampling * __num_parts + 1); __os_starts[0] = __begin; _IIter __prev = __begin, __it = __begin; size_t __dist_limit = 0, __dist = 0; size_t __cur = 1, __next = 1; size_t __range_length = 1; size_t __count_to_two = 0; while (__it != __end) { __cur = __next; for (; __cur < __os_starts.size() and __it != __end; ++__cur) { for (__dist_limit += __range_length; __dist < __dist_limit and __it != __end; ++__dist) { __f(__it); ++__it; } __os_starts[__cur] = __it; } // Must compare for end and not __cur < __os_starts.size() , because // __cur could be == __os_starts.size() as well if (__it == __end) break; __shrink_and_double(__os_starts, __count_to_two, __range_length, __make_twice); __next = __os_starts.size() / 2 + 1; } // Calculation of the parts (one must be extracted from __current // because the partition beginning at end, consists only of // itself). size_t __size_part = (__cur - 1) / __num_parts; int __size_greater = static_cast<int>((__cur - 1) % __num_parts); __starts[0] = __os_starts[0]; size_t __index = 0; // Smallest partitions. for (int __i = 1; __i < (__num_parts + 1 - __size_greater); ++__i) { __lengths[__i - 1] = __size_part * __range_length; __index += __size_part; __starts[__i] = __os_starts[__index]; } // Biggest partitions. for (int __i = __num_parts + 1 - __size_greater; __i <= __num_parts; ++__i) { __lengths[__i - 1] = (__size_part+1) * __range_length; __index += (__size_part+1); __starts[__i] = __os_starts[__index]; } // Correction of the end size (the end iteration has not finished). __lengths[__num_parts - 1] -= (__dist_limit - __dist); return __dist; } } #endif /* _GLIBCXX_PARALLEL_LIST_PARTITION_H */	6.39 KB	2025-09-15 15:41
📄 losertree.h // -- C++ -- // Copyright (C) 2007-2021 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/losertree.h * @brief Many generic loser tree variants. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_LOSERTREE_H #define _GLIBCXX_PARALLEL_LOSERTREE_H 1 #include <bits/stl_algobase.h> #include <bits/stl_function.h> #include <parallel/features.h> #include <parallel/base.h> namespace __gnu_parallel { /* * @brief Guarded loser/tournament tree. * * The smallest element is at the top. * * Guarding is done explicitly through one flag _M_sup per element, * inf is not needed due to a better initialization routine. This * is a well-performing variant. * * @param _Tp the element type * @param _Compare the comparator to use, defaults to std::less<_Tp> / template<typename _Tp, typename _Compare> class _LoserTreeBase { protected: /* @brief Internal representation of a _LoserTree element. / struct _Loser { /* @brief flag, true iff this is a "maximum" __sentinel. / bool _M_sup; /* @brief __index of the __source __sequence. / int _M_source; /* @brief _M_key of the element in the _LoserTree. / _Tp _M_key; }; unsigned int _M_ik, _M_k, _M_offset; /* log_2{_M_k} / unsigned int _M_log_k; /* @brief _LoserTree __elements. / _Loser _M_losers; /** @brief _Compare to use. / _Compare _M_comp; /* * @brief State flag that determines whether the _LoserTree is empty. * * Only used for building the _LoserTree. / bool _M_first_insert; public: /* * @brief The constructor. * * @param __k The number of sequences to merge. * @param __comp The comparator to use. / _LoserTreeBase(unsigned int __k, _Compare __comp) : _M_comp(__comp) { _M_ik = __k; // Compute log_2{_M_k} for the _Loser Tree _M_log_k = __rd_log2(_M_ik - 1) + 1; // Next greater power of 2. _M_k = 1 << _M_log_k; _M_offset = _M_k; // Avoid default-constructing _M_losers[]._M_key _M_losers = static_cast<_Loser>(::operator new(2 * _M_k * sizeof(_Loser))); for (unsigned int __i = _M_ik - 1; __i < _M_k; ++__i) _M_losers[__i + _M_k]._M_sup = true; _M_first_insert = true; } /** * @brief The destructor. / ~_LoserTreeBase() { for (unsigned int __i = 0; __i < (2 _M_k); ++__i) _M_losers[__i].~_Loser(); ::operator delete(_M_losers); } /** * @brief Initializes the sequence "_M_source" with the element "__key". * * @param __key the element to insert * @param __source __index of the __source __sequence * @param __sup flag that determines whether the value to insert is an * explicit __supremum. / void __insert_start(const _Tp& __key, int __source, bool __sup) { unsigned int __pos = _M_k + __source; if (_M_first_insert) { // Construct all keys, so we can easily destruct them. for (unsigned int __i = 0; __i < (2 _M_k); ++__i) ::new(&(_M_losers[__i]._M_key)) _Tp(__key); _M_first_insert = false; } else _M_losers[__pos]._M_key = __key; _M_losers[__pos]._M_sup = __sup; _M_losers[__pos]._M_source = __source; } /** * @return the index of the sequence with the smallest element. / int __get_min_source() { return _M_losers[0]._M_source; } }; /* * @brief Stable _LoserTree variant. * * Provides the stable implementations of insert_start, __init_winner, * __init and __delete_min_insert. * * Unstable variant is done using partial specialisation below. / template<bool __stable/ default == true /, typename _Tp, typename _Compare> class _LoserTree : public _LoserTreeBase<_Tp, _Compare> { typedef _LoserTreeBase<_Tp, _Compare> _Base; using _Base::_M_k; using _Base::_M_comp; using _Base::_M_losers; using _Base::_M_first_insert; public: _LoserTree(unsigned int __k, _Compare __comp) : _Base::_LoserTreeBase(__k, __comp) { } unsigned int __init_winner(unsigned int __root) { if (__root >= _M_k) return __root; else { unsigned int __left = __init_winner(2 __root); unsigned int __right = __init_winner(2 * __root + 1); if (_M_losers[__right]._M_sup \|\| (!_M_losers[__left]._M_sup && !_M_comp(_M_losers[__right]._M_key, _M_losers[__left]._M_key))) { // Left one is less or equal. _M_losers[__root] = _M_losers[__right]; return __left; } else { // Right one is less. _M_losers[__root] = _M_losers[__left]; return __right; } } } void __init() { _M_losers[0] = _M_losers[__init_winner(1)]; } /** * @brief Delete the smallest element and insert a new element from * the previously smallest element's sequence. * * This implementation is stable. / // Do not pass a const reference since __key will be used as // local variable. void __delete_min_insert(_Tp __key, bool __sup) { using std::swap; #if _GLIBCXX_PARALLEL_ASSERTIONS // no dummy sequence can ever be at the top! _GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1); #endif int __source = _M_losers[0]._M_source; for (unsigned int __pos = (_M_k + __source) / 2; __pos > 0; __pos /= 2) { // The smaller one gets promoted, ties are broken by _M_source. if ((__sup && (!_M_losers[__pos]._M_sup \|\| _M_losers[__pos]._M_source < __source)) \|\| (!__sup && !_M_losers[__pos]._M_sup && ((_M_comp(_M_losers[__pos]._M_key, __key)) \|\| (!_M_comp(__key, _M_losers[__pos]._M_key) && _M_losers[__pos]._M_source < __source)))) { // The other one is smaller. std::swap(_M_losers[__pos]._M_sup, __sup); std::swap(_M_losers[__pos]._M_source, __source); swap(_M_losers[__pos]._M_key, __key); } } _M_losers[0]._M_sup = __sup; _M_losers[0]._M_source = __source; _M_losers[0]._M_key = __key; } }; /* * @brief Unstable _LoserTree variant. * * Stability (non-stable here) is selected with partial specialization. / template<typename _Tp, typename _Compare> class _LoserTree</ __stable == /false, _Tp, _Compare> : public _LoserTreeBase<_Tp, _Compare> { typedef _LoserTreeBase<_Tp, _Compare> _Base; using _Base::_M_log_k; using _Base::_M_k; using _Base::_M_comp; using _Base::_M_losers; using _Base::_M_first_insert; public: _LoserTree(unsigned int __k, _Compare __comp) : _Base::_LoserTreeBase(__k, __comp) { } /* * Computes the winner of the competition at position "__root". * * Called recursively (starting at 0) to build the initial tree. * * @param __root __index of the "game" to start. / unsigned int __init_winner(unsigned int __root) { if (__root >= _M_k) return __root; else { unsigned int __left = __init_winner(2 __root); unsigned int __right = __init_winner(2 * __root + 1); if (_M_losers[__right]._M_sup \|\| (!_M_losers[__left]._M_sup && !_M_comp(_M_losers[__right]._M_key, _M_losers[__left]._M_key))) { // Left one is less or equal. _M_losers[__root] = _M_losers[__right]; return __left; } else { // Right one is less. _M_losers[__root] = _M_losers[__left]; return __right; } } } void __init() { _M_losers[0] = _M_losers[__init_winner(1)]; } /** * Delete the _M_key smallest element and insert the element __key * instead. * * @param __key the _M_key to insert * @param __sup true iff __key is an explicitly marked supremum / // Do not pass a const reference since __key will be used as local // variable. void __delete_min_insert(_Tp __key, bool __sup) { using std::swap; #if _GLIBCXX_PARALLEL_ASSERTIONS // no dummy sequence can ever be at the top! _GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1); #endif int __source = _M_losers[0]._M_source; for (unsigned int __pos = (_M_k + __source) / 2; __pos > 0; __pos /= 2) { // The smaller one gets promoted. if (__sup \|\| (!_M_losers[__pos]._M_sup && _M_comp(_M_losers[__pos]._M_key, __key))) { // The other one is smaller. std::swap(_M_losers[__pos]._M_sup, __sup); std::swap(_M_losers[__pos]._M_source, __source); swap(_M_losers[__pos]._M_key, __key); } } _M_losers[0]._M_sup = __sup; _M_losers[0]._M_source = __source; _M_losers[0]._M_key = __key; } }; /* * @brief Base class of _Loser Tree implementation using pointers. / template<typename _Tp, typename _Compare> class _LoserTreePointerBase { protected: /* @brief Internal representation of _LoserTree __elements. / struct _Loser { bool _M_sup; int _M_source; const _Tp _M_keyp; }; unsigned int _M_ik, _M_k, _M_offset; _Loser* _M_losers; _Compare _M_comp; public: _LoserTreePointerBase(unsigned int __k, _Compare __comp = std::less<_Tp>()) : _M_comp(__comp) { _M_ik = __k; // Next greater power of 2. _M_k = 1 << (__rd_log2(_M_ik - 1) + 1); _M_offset = _M_k; _M_losers = new _Loser[_M_k * 2]; for (unsigned int __i = _M_ik - 1; __i < _M_k; __i++) _M_losers[__i + _M_k]._M_sup = true; } ~_LoserTreePointerBase() { delete[] _M_losers; } int __get_min_source() { return _M_losers[0]._M_source; } void __insert_start(const _Tp& __key, int __source, bool __sup) { unsigned int __pos = _M_k + __source; _M_losers[__pos]._M_sup = __sup; _M_losers[__pos]._M_source = __source; _M_losers[__pos]._M_keyp = &__key; } }; /** * @brief Stable _LoserTree implementation. * * The unstable variant is implemented using partial instantiation below. / template<bool __stable/ default == true /, typename _Tp, typename _Compare> class _LoserTreePointer : public _LoserTreePointerBase<_Tp, _Compare> { typedef _LoserTreePointerBase<_Tp, _Compare> _Base; using _Base::_M_k; using _Base::_M_comp; using _Base::_M_losers; public: _LoserTreePointer(unsigned int __k, _Compare __comp = std::less<_Tp>()) : _Base::_LoserTreePointerBase(__k, __comp) { } unsigned int __init_winner(unsigned int __root) { if (__root >= _M_k) return __root; else { unsigned int __left = __init_winner(2 __root); unsigned int __right = __init_winner(2 * __root + 1); if (_M_losers[__right]._M_sup \|\| (!_M_losers[__left]._M_sup && !_M_comp(_M_losers[__right]._M_keyp, _M_losers[__left]._M_keyp))) { // Left one is less or equal. _M_losers[__root] = _M_losers[__right]; return __left; } else { // Right one is less. _M_losers[__root] = _M_losers[__left]; return __right; } } } void __init() { _M_losers[0] = _M_losers[__init_winner(1)]; } void __delete_min_insert(const _Tp& __key, bool __sup) { #if _GLIBCXX_PARALLEL_ASSERTIONS // no dummy sequence can ever be at the top! _GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1); #endif const _Tp* __keyp = &__key; int __source = _M_losers[0]._M_source; for (unsigned int __pos = (_M_k + __source) / 2; __pos > 0; __pos /= 2) { // The smaller one gets promoted, ties are broken by __source. if ((__sup && (!_M_losers[__pos]._M_sup \|\| _M_losers[__pos]._M_source < __source)) \|\| (!__sup && !_M_losers[__pos]._M_sup && ((_M_comp(_M_losers[__pos]._M_keyp, __keyp)) \|\| (!_M_comp(__keyp, _M_losers[__pos]._M_keyp) && _M_losers[__pos]._M_source < __source)))) { // The other one is smaller. std::swap(_M_losers[__pos]._M_sup, __sup); std::swap(_M_losers[__pos]._M_source, __source); std::swap(_M_losers[__pos]._M_keyp, __keyp); } } _M_losers[0]._M_sup = __sup; _M_losers[0]._M_source = __source; _M_losers[0]._M_keyp = __keyp; } }; /** * @brief Unstable _LoserTree implementation. * * The stable variant is above. / template<typename _Tp, typename _Compare> class _LoserTreePointer</ __stable == /false, _Tp, _Compare> : public _LoserTreePointerBase<_Tp, _Compare> { typedef _LoserTreePointerBase<_Tp, _Compare> _Base; using _Base::_M_k; using _Base::_M_comp; using _Base::_M_losers; public: _LoserTreePointer(unsigned int __k, _Compare __comp = std::less<_Tp>()) : _Base::_LoserTreePointerBase(__k, __comp) { } unsigned int __init_winner(unsigned int __root) { if (__root >= _M_k) return __root; else { unsigned int __left = __init_winner(2 __root); unsigned int __right = __init_winner(2 * __root + 1); if (_M_losers[__right]._M_sup \|\| (!_M_losers[__left]._M_sup && !_M_comp(_M_losers[__right]._M_keyp, _M_losers[__left]._M_keyp))) { // Left one is less or equal. _M_losers[__root] = _M_losers[__right]; return __left; } else { // Right one is less. _M_losers[__root] = _M_losers[__left]; return __right; } } } void __init() { _M_losers[0] = _M_losers[__init_winner(1)]; } void __delete_min_insert(const _Tp& __key, bool __sup) { #if _GLIBCXX_PARALLEL_ASSERTIONS // no dummy sequence can ever be at the top! _GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1); #endif const _Tp* __keyp = &__key; int __source = _M_losers[0]._M_source; for (unsigned int __pos = (_M_k + __source) / 2; __pos > 0; __pos /= 2) { // The smaller one gets promoted. if (__sup \|\| (!_M_losers[__pos]._M_sup && _M_comp(_M_losers[__pos]._M_keyp, __keyp))) { // The other one is smaller. std::swap(_M_losers[__pos]._M_sup, __sup); std::swap(_M_losers[__pos]._M_source, __source); std::swap(_M_losers[__pos]._M_keyp, __keyp); } } _M_losers[0]._M_sup = __sup; _M_losers[0]._M_source = __source; _M_losers[0]._M_keyp = __keyp; } }; /** @brief Base class for unguarded _LoserTree implementation. * * The whole element is copied into the tree structure. * * No guarding is done, therefore not a single input sequence must * run empty. Unused __sequence heads are marked with a sentinel which * is > all elements that are to be merged. * * This is a very fast variant. / template<typename _Tp, typename _Compare> class _LoserTreeUnguardedBase { protected: struct _Loser { int _M_source; _Tp _M_key; }; unsigned int _M_ik, _M_k, _M_offset; _Loser _M_losers; _Compare _M_comp; public: _LoserTreeUnguardedBase(unsigned int __k, const _Tp& __sentinel, _Compare __comp = std::less<_Tp>()) : _M_comp(__comp) { _M_ik = __k; // Next greater power of 2. _M_k = 1 << (__rd_log2(_M_ik - 1) + 1); _M_offset = _M_k; // Avoid default-constructing _M_losers[]._M_key _M_losers = static_cast<_Loser>(::operator new(2 _M_k * sizeof(_Loser))); for (unsigned int __i = 0; __i < _M_k; ++__i) { ::new(&(_M_losers[__i]._M_key)) _Tp(__sentinel); _M_losers[__i]._M_source = -1; } for (unsigned int __i = _M_k + _M_ik - 1; __i < (2 * _M_k); ++__i) { ::new(&(_M_losers[__i]._M_key)) _Tp(__sentinel); _M_losers[__i]._M_source = -1; } } ~_LoserTreeUnguardedBase() { for (unsigned int __i = 0; __i < (2 * _M_k); ++__i) _M_losers[__i].~_Loser(); ::operator delete(_M_losers); } int __get_min_source() { #if _GLIBCXX_PARALLEL_ASSERTIONS // no dummy sequence can ever be at the top! _GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1); #endif return _M_losers[0]._M_source; } void __insert_start(const _Tp& __key, int __source, bool) { unsigned int __pos = _M_k + __source; ::new(&(_M_losers[__pos]._M_key)) _Tp(__key); _M_losers[__pos]._M_source = __source; } }; /** * @brief Stable implementation of unguarded _LoserTree. * * Unstable variant is selected below with partial specialization. / template<bool __stable/ default == true /, typename _Tp, typename _Compare> class _LoserTreeUnguarded : public _LoserTreeUnguardedBase<_Tp, _Compare> { typedef _LoserTreeUnguardedBase<_Tp, _Compare> _Base; using _Base::_M_k; using _Base::_M_comp; using _Base::_M_losers; public: _LoserTreeUnguarded(unsigned int __k, const _Tp& __sentinel, _Compare __comp = std::less<_Tp>()) : _Base::_LoserTreeUnguardedBase(__k, __sentinel, __comp) { } unsigned int __init_winner(unsigned int __root) { if (__root >= _M_k) return __root; else { unsigned int __left = __init_winner(2 __root); unsigned int __right = __init_winner(2 * __root + 1); if (!_M_comp(_M_losers[__right]._M_key, _M_losers[__left]._M_key)) { // Left one is less or equal. _M_losers[__root] = _M_losers[__right]; return __left; } else { // Right one is less. _M_losers[__root] = _M_losers[__left]; return __right; } } } void __init() { _M_losers[0] = _M_losers[__init_winner(1)]; #if _GLIBCXX_PARALLEL_ASSERTIONS // no dummy sequence can ever be at the top at the beginning // (0 sequences!) _GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1); #endif } // Do not pass a const reference since __key will be used as // local variable. void __delete_min_insert(_Tp __key, bool) { using std::swap; #if _GLIBCXX_PARALLEL_ASSERTIONS // no dummy sequence can ever be at the top! _GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1); #endif int __source = _M_losers[0]._M_source; for (unsigned int __pos = (_M_k + __source) / 2; __pos > 0; __pos /= 2) { // The smaller one gets promoted, ties are broken by _M_source. if (_M_comp(_M_losers[__pos]._M_key, __key) \|\| (!_M_comp(__key, _M_losers[__pos]._M_key) && _M_losers[__pos]._M_source < __source)) { // The other one is smaller. std::swap(_M_losers[__pos]._M_source, __source); swap(_M_losers[__pos]._M_key, __key); } } _M_losers[0]._M_source = __source; _M_losers[0]._M_key = __key; } }; /** * @brief Non-Stable implementation of unguarded _LoserTree. * * Stable implementation is above. / template<typename _Tp, typename _Compare> class _LoserTreeUnguarded</ __stable == /false, _Tp, _Compare> : public _LoserTreeUnguardedBase<_Tp, _Compare> { typedef _LoserTreeUnguardedBase<_Tp, _Compare> _Base; using _Base::_M_k; using _Base::_M_comp; using _Base::_M_losers; public: _LoserTreeUnguarded(unsigned int __k, const _Tp& __sentinel, _Compare __comp = std::less<_Tp>()) : _Base::_LoserTreeUnguardedBase(__k, __sentinel, __comp) { } unsigned int __init_winner(unsigned int __root) { if (__root >= _M_k) return __root; else { unsigned int __left = __init_winner(2 __root); unsigned int __right = __init_winner(2 * __root + 1); #if _GLIBCXX_PARALLEL_ASSERTIONS // If __left one is sentinel then __right one must be, too. if (_M_losers[__left]._M_source == -1) _GLIBCXX_PARALLEL_ASSERT(_M_losers[__right]._M_source == -1); #endif if (!_M_comp(_M_losers[__right]._M_key, _M_losers[__left]._M_key)) { // Left one is less or equal. _M_losers[__root] = _M_losers[__right]; return __left; } else { // Right one is less. _M_losers[__root] = _M_losers[__left]; return __right; } } } void __init() { _M_losers[0] = _M_losers[__init_winner(1)]; #if _GLIBCXX_PARALLEL_ASSERTIONS // no dummy sequence can ever be at the top at the beginning // (0 sequences!) _GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1); #endif } // Do not pass a const reference since __key will be used as // local variable. void __delete_min_insert(_Tp __key, bool) { using std::swap; #if _GLIBCXX_PARALLEL_ASSERTIONS // no dummy sequence can ever be at the top! _GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1); #endif int __source = _M_losers[0]._M_source; for (unsigned int __pos = (_M_k + __source) / 2; __pos > 0; __pos /= 2) { // The smaller one gets promoted. if (_M_comp(_M_losers[__pos]._M_key, __key)) { // The other one is smaller. std::swap(_M_losers[__pos]._M_source, __source); swap(_M_losers[__pos]._M_key, __key); } } _M_losers[0]._M_source = __source; _M_losers[0]._M_key = __key; } }; /** @brief Unguarded loser tree, keeping only pointers to the * elements in the tree structure. * * No guarding is done, therefore not a single input sequence must * run empty. This is a very fast variant. / template<typename _Tp, typename _Compare> class _LoserTreePointerUnguardedBase { protected: struct _Loser { int _M_source; const _Tp _M_keyp; }; unsigned int _M_ik, _M_k, _M_offset; _Loser* _M_losers; _Compare _M_comp; public: _LoserTreePointerUnguardedBase(unsigned int __k, const _Tp& __sentinel, _Compare __comp = std::less<_Tp>()) : _M_comp(__comp) { _M_ik = __k; // Next greater power of 2. _M_k = 1 << (__rd_log2(_M_ik - 1) + 1); _M_offset = _M_k; // Avoid default-constructing _M_losers[]._M_key _M_losers = new _Loser[2 * _M_k]; for (unsigned int __i = _M_k + _M_ik - 1; __i < (2 * _M_k); ++__i) { _M_losers[__i]._M_keyp = &__sentinel; _M_losers[__i]._M_source = -1; } } ~_LoserTreePointerUnguardedBase() { delete[] _M_losers; } int __get_min_source() { #if _GLIBCXX_PARALLEL_ASSERTIONS // no dummy sequence can ever be at the top! _GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1); #endif return _M_losers[0]._M_source; } void __insert_start(const _Tp& __key, int __source, bool) { unsigned int __pos = _M_k + __source; _M_losers[__pos]._M_keyp = &__key; _M_losers[__pos]._M_source = __source; } }; /** * @brief Stable unguarded _LoserTree variant storing pointers. * * Unstable variant is implemented below using partial specialization. / template<bool __stable/ default == true /, typename _Tp, typename _Compare> class _LoserTreePointerUnguarded : public _LoserTreePointerUnguardedBase<_Tp, _Compare> { typedef _LoserTreePointerUnguardedBase<_Tp, _Compare> _Base; using _Base::_M_k; using _Base::_M_comp; using _Base::_M_losers; public: _LoserTreePointerUnguarded(unsigned int __k, const _Tp& __sentinel, _Compare __comp = std::less<_Tp>()) : _Base::_LoserTreePointerUnguardedBase(__k, __sentinel, __comp) { } unsigned int __init_winner(unsigned int __root) { if (__root >= _M_k) return __root; else { unsigned int __left = __init_winner(2 __root); unsigned int __right = __init_winner(2 * __root + 1); if (!_M_comp(_M_losers[__right]._M_keyp, _M_losers[__left]._M_keyp)) { // Left one is less or equal. _M_losers[__root] = _M_losers[__right]; return __left; } else { // Right one is less. _M_losers[__root] = _M_losers[__left]; return __right; } } } void __init() { _M_losers[0] = _M_losers[__init_winner(1)]; #if _GLIBCXX_PARALLEL_ASSERTIONS // no dummy sequence can ever be at the top at the beginning // (0 sequences!) _GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1); #endif } void __delete_min_insert(const _Tp& __key, bool __sup) { #if _GLIBCXX_PARALLEL_ASSERTIONS // no dummy sequence can ever be at the top! _GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1); #endif const _Tp* __keyp = &__key; int __source = _M_losers[0]._M_source; for (unsigned int __pos = (_M_k + __source) / 2; __pos > 0; __pos /= 2) { // The smaller one gets promoted, ties are broken by _M_source. if (_M_comp(_M_losers[__pos]._M_keyp, __keyp) \|\| (!_M_comp(__keyp, _M_losers[__pos]._M_keyp) && _M_losers[__pos]._M_source < __source)) { // The other one is smaller. std::swap(_M_losers[__pos]._M_source, __source); std::swap(_M_losers[__pos]._M_keyp, __keyp); } } _M_losers[0]._M_source = __source; _M_losers[0]._M_keyp = __keyp; } }; /** * @brief Unstable unguarded _LoserTree variant storing pointers. * * Stable variant is above. / template<typename _Tp, typename _Compare> class _LoserTreePointerUnguarded</ __stable == /false, _Tp, _Compare> : public _LoserTreePointerUnguardedBase<_Tp, _Compare> { typedef _LoserTreePointerUnguardedBase<_Tp, _Compare> _Base; using _Base::_M_k; using _Base::_M_comp; using _Base::_M_losers; public: _LoserTreePointerUnguarded(unsigned int __k, const _Tp& __sentinel, _Compare __comp = std::less<_Tp>()) : _Base::_LoserTreePointerUnguardedBase(__k, __sentinel, __comp) { } unsigned int __init_winner(unsigned int __root) { if (__root >= _M_k) return __root; else { unsigned int __left = __init_winner(2 __root); unsigned int __right = __init_winner(2 * __root + 1); #if _GLIBCXX_PARALLEL_ASSERTIONS // If __left one is sentinel then __right one must be, too. if (_M_losers[__left]._M_source == -1) _GLIBCXX_PARALLEL_ASSERT(_M_losers[__right]._M_source == -1); #endif if (!_M_comp(_M_losers[__right]._M_keyp, _M_losers[__left]._M_keyp)) { // Left one is less or equal. _M_losers[__root] = _M_losers[__right]; return __left; } else { // Right one is less. _M_losers[__root] = _M_losers[__left]; return __right; } } } void __init() { _M_losers[0] = _M_losers[__init_winner(1)]; #if _GLIBCXX_PARALLEL_ASSERTIONS // no dummy sequence can ever be at the top at the beginning // (0 sequences!) _GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1); #endif } void __delete_min_insert(const _Tp& __key, bool __sup) { #if _GLIBCXX_PARALLEL_ASSERTIONS // no dummy sequence can ever be at the top! _GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1); #endif const _Tp* __keyp = &__key; int __source = _M_losers[0]._M_source; for (unsigned int __pos = (_M_k + __source) / 2; __pos > 0; __pos /= 2) { // The smaller one gets promoted. if (_M_comp((_M_losers[__pos]._M_keyp), __keyp)) { // The other one is smaller. std::swap(_M_losers[__pos]._M_source, __source); std::swap(_M_losers[__pos]._M_keyp, __keyp); } } _M_losers[0]._M_source = __source; _M_losers[0]._M_keyp = __keyp; } }; } // namespace __gnu_parallel #endif /* _GLIBCXX_PARALLEL_LOSERTREE_H */	27.92 KB	2025-09-15 15:41
📄 merge.h // -- C++ -- // Copyright (C) 2007-2021 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/merge.h * @brief Parallel implementation of std::merge(). * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_MERGE_H #define _GLIBCXX_PARALLEL_MERGE_H 1 #include <parallel/basic_iterator.h> #include <bits/stl_algo.h> namespace __gnu_parallel { /* @brief Merge routine being able to merge only the @c __max_length * smallest elements. * * The @c __begin iterators are advanced accordingly, they might not * reach @c __end, in contrast to the usual variant. * @param __begin1 Begin iterator of first sequence. * @param __end1 End iterator of first sequence. * @param __begin2 Begin iterator of second sequence. * @param __end2 End iterator of second sequence. * @param __target Target begin iterator. * @param __max_length Maximum number of elements to merge. * @param __comp Comparator. * @return Output end iterator. / template<typename _RAIter1, typename _RAIter2, typename _OutputIterator, typename _DifferenceTp, typename _Compare> _OutputIterator __merge_advance_usual(_RAIter1& __begin1, _RAIter1 __end1, _RAIter2& __begin2, _RAIter2 __end2, _OutputIterator __target, _DifferenceTp __max_length, _Compare __comp) { typedef _DifferenceTp _DifferenceType; while (__begin1 != __end1 && __begin2 != __end2 && __max_length > 0) { // array1[__i1] < array0[i0] if (__comp(__begin2, __begin1)) __target++ = __begin2++; else __target++ = __begin1++; --__max_length; } if (__begin1 != __end1) { __target = std::copy(__begin1, __begin1 + __max_length, __target); __begin1 += __max_length; } else { __target = std::copy(__begin2, __begin2 + __max_length, __target); __begin2 += __max_length; } return __target; } /* @brief Merge routine being able to merge only the @c __max_length * smallest elements. * * The @c __begin iterators are advanced accordingly, they might not * reach @c __end, in contrast to the usual variant. * Specially designed code should allow the compiler to generate * conditional moves instead of branches. * @param __begin1 Begin iterator of first sequence. * @param __end1 End iterator of first sequence. * @param __begin2 Begin iterator of second sequence. * @param __end2 End iterator of second sequence. * @param __target Target begin iterator. * @param __max_length Maximum number of elements to merge. * @param __comp Comparator. * @return Output end iterator. / template<typename _RAIter1, typename _RAIter2, typename _OutputIterator, typename _DifferenceTp, typename _Compare> _OutputIterator __merge_advance_movc(_RAIter1& __begin1, _RAIter1 __end1, _RAIter2& __begin2, _RAIter2 __end2, _OutputIterator __target, _DifferenceTp __max_length, _Compare __comp) { typedef _DifferenceTp _DifferenceType; typedef typename std::iterator_traits<_RAIter1>::value_type _ValueType1; typedef typename std::iterator_traits<_RAIter2>::value_type _ValueType2; #if _GLIBCXX_PARALLEL_ASSERTIONS _GLIBCXX_PARALLEL_ASSERT(__max_length >= 0); #endif while (__begin1 != __end1 && __begin2 != __end2 && __max_length > 0) { _RAIter1 __next1 = __begin1 + 1; _RAIter2 __next2 = __begin2 + 1; _ValueType1 __element1 = __begin1; _ValueType2 __element2 = __begin2; if (__comp(__element2, __element1)) { __element1 = __element2; __begin2 = __next2; } else __begin1 = __next1; __target = __element1; ++__target; --__max_length; } if (__begin1 != __end1) { __target = std::copy(__begin1, __begin1 + __max_length, __target); __begin1 += __max_length; } else { __target = std::copy(__begin2, __begin2 + __max_length, __target); __begin2 += __max_length; } return __target; } /** @brief Merge routine being able to merge only the @c __max_length * smallest elements. * * The @c __begin iterators are advanced accordingly, they might not * reach @c __end, in contrast to the usual variant. * Static switch on whether to use the conditional-move variant. * @param __begin1 Begin iterator of first sequence. * @param __end1 End iterator of first sequence. * @param __begin2 Begin iterator of second sequence. * @param __end2 End iterator of second sequence. * @param __target Target begin iterator. * @param __max_length Maximum number of elements to merge. * @param __comp Comparator. * @return Output end iterator. / template<typename _RAIter1, typename _RAIter2, typename _OutputIterator, typename _DifferenceTp, typename _Compare> inline _OutputIterator __merge_advance(_RAIter1& __begin1, _RAIter1 __end1, _RAIter2& __begin2, _RAIter2 __end2, _OutputIterator __target, _DifferenceTp __max_length, _Compare __comp) { _GLIBCXX_CALL(__max_length) return __merge_advance_movc(__begin1, __end1, __begin2, __end2, __target, __max_length, __comp); } /* @brief Merge routine fallback to sequential in case the iterators of the two input sequences are of different type. * @param __begin1 Begin iterator of first sequence. * @param __end1 End iterator of first sequence. * @param __begin2 Begin iterator of second sequence. * @param __end2 End iterator of second sequence. * @param __target Target begin iterator. * @param __max_length Maximum number of elements to merge. * @param __comp Comparator. * @return Output end iterator. / template<typename _RAIter1, typename _RAIter2, typename _RAIter3, typename _Compare> inline _RAIter3 __parallel_merge_advance(_RAIter1& __begin1, _RAIter1 __end1, _RAIter2& __begin2, // different iterators, parallel implementation // not available _RAIter2 __end2, _RAIter3 __target, typename std::iterator_traits<_RAIter1>:: difference_type __max_length, _Compare __comp) { return __merge_advance(__begin1, __end1, __begin2, __end2, __target, __max_length, __comp); } /* @brief Parallel merge routine being able to merge only the @c * __max_length smallest elements. * * The @c __begin iterators are advanced accordingly, they might not * reach @c __end, in contrast to the usual variant. * The functionality is projected onto parallel_multiway_merge. * @param __begin1 Begin iterator of first sequence. * @param __end1 End iterator of first sequence. * @param __begin2 Begin iterator of second sequence. * @param __end2 End iterator of second sequence. * @param __target Target begin iterator. * @param __max_length Maximum number of elements to merge. * @param __comp Comparator. * @return Output end iterator. / template<typename _RAIter1, typename _RAIter3, typename _Compare> inline _RAIter3 __parallel_merge_advance(_RAIter1& __begin1, _RAIter1 __end1, _RAIter1& __begin2, _RAIter1 __end2, _RAIter3 __target, typename std::iterator_traits<_RAIter1>:: difference_type __max_length, _Compare __comp) { typedef typename std::iterator_traits<_RAIter1>::value_type _ValueType; typedef typename std::iterator_traits<_RAIter1>:: difference_type _DifferenceType1 / == difference_type2 /; typedef typename std::iterator_traits<_RAIter3>:: difference_type _DifferenceType3; typedef typename std::pair<_RAIter1, _RAIter1> _IteratorPair; _IteratorPair __seqs[2] = { std::make_pair(__begin1, __end1), std::make_pair(__begin2, __end2) }; _RAIter3 __target_end = parallel_multiway_merge < / __stable = / true, / __sentinels = / false> (__seqs, __seqs + 2, __target, multiway_merge_exact_splitting < / __stable = / true, _IteratorPair, _Compare, _DifferenceType1>, __max_length, __comp, omp_get_max_threads()); return __target_end; } } //namespace __gnu_parallel #endif /* _GLIBCXX_PARALLEL_MERGE_H */	9.35 KB	2025-09-15 15:41
📄 multiseq_selection.h // -- C++ -- // Copyright (C) 2007-2021 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/multiseq_selection.h * @brief Functions to find elements of a certain global __rank in * multiple sorted sequences. Also serves for splitting such * sequence sets. * * The algorithm description can be found in * * P. J. Varman, S. D. Scheufler, B. R. Iyer, and G. R. Ricard. * Merging Multiple Lists on Hierarchical-Memory Multiprocessors. * Journal of Parallel and Distributed Computing, 12(2):171-177, 1991. * * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_MULTISEQ_SELECTION_H #define _GLIBCXX_PARALLEL_MULTISEQ_SELECTION_H 1 #include <vector> #include <queue> #include <bits/stl_algo.h> namespace __gnu_parallel { /* @brief Compare __a pair of types lexicographically, ascending. / template<typename _T1, typename _T2, typename _Compare> class _Lexicographic : public std::binary_function<std::pair<_T1, _T2>, std::pair<_T1, _T2>, bool> { private: _Compare& _M_comp; public: _Lexicographic(_Compare& __comp) : _M_comp(__comp) { } bool operator()(const std::pair<_T1, _T2>& __p1, const std::pair<_T1, _T2>& __p2) const { if (_M_comp(__p1.first, __p2.first)) return true; if (_M_comp(__p2.first, __p1.first)) return false; // Firsts are equal. return __p1.second < __p2.second; } }; /* @brief Compare __a pair of types lexicographically, descending. / template<typename _T1, typename _T2, typename _Compare> class _LexicographicReverse : public std::binary_function<_T1, _T2, bool> { private: _Compare& _M_comp; public: _LexicographicReverse(_Compare& __comp) : _M_comp(__comp) { } bool operator()(const std::pair<_T1, _T2>& __p1, const std::pair<_T1, _T2>& __p2) const { if (_M_comp(__p2.first, __p1.first)) return true; if (_M_comp(__p1.first, __p2.first)) return false; // Firsts are equal. return __p2.second < __p1.second; } }; /* * @brief Splits several sorted sequences at a certain global __rank, * resulting in a splitting point for each sequence. * The sequences are passed via a sequence of random-access * iterator pairs, none of the sequences may be empty. If there * are several equal elements across the split, the ones on the * __left side will be chosen from sequences with smaller number. * @param __begin_seqs Begin of the sequence of iterator pairs. * @param __end_seqs End of the sequence of iterator pairs. * @param __rank The global rank to partition at. * @param __begin_offsets A random-access __sequence __begin where the * __result will be stored in. Each element of the sequence is an * iterator that points to the first element on the greater part of * the respective __sequence. * @param __comp The ordering functor, defaults to std::less<_Tp>. / template<typename _RanSeqs, typename _RankType, typename _RankIterator, typename _Compare> void multiseq_partition(_RanSeqs __begin_seqs, _RanSeqs __end_seqs, _RankType __rank, _RankIterator __begin_offsets, _Compare __comp = std::less< typename std::iterator_traits<typename std::iterator_traits<_RanSeqs>::value_type:: first_type>::value_type>()) // std::less<_Tp> { _GLIBCXX_CALL(__end_seqs - __begin_seqs) typedef typename std::iterator_traits<_RanSeqs>::value_type::first_type _It; typedef typename std::iterator_traits<_RanSeqs>::difference_type _SeqNumber; typedef typename std::iterator_traits<_It>::difference_type _DifferenceType; typedef typename std::iterator_traits<_It>::value_type _ValueType; _Lexicographic<_ValueType, _SeqNumber, _Compare> __lcomp(__comp); _LexicographicReverse<_ValueType, _SeqNumber, _Compare> __lrcomp(__comp); // Number of sequences, number of elements in total (possibly // including padding). _DifferenceType __m = std::distance(__begin_seqs, __end_seqs), __nn = 0, __nmax, __n, __r; for (_SeqNumber __i = 0; __i < __m; __i++) { __nn += std::distance(__begin_seqs[__i].first, __begin_seqs[__i].second); _GLIBCXX_PARALLEL_ASSERT( std::distance(__begin_seqs[__i].first, __begin_seqs[__i].second) > 0); } if (__rank == __nn) { for (_SeqNumber __i = 0; __i < __m; __i++) __begin_offsets[__i] = __begin_seqs[__i].second; // Very end. // Return __m - 1; return; } _GLIBCXX_PARALLEL_ASSERT(__m != 0); _GLIBCXX_PARALLEL_ASSERT(__nn != 0); _GLIBCXX_PARALLEL_ASSERT(__rank >= 0); _GLIBCXX_PARALLEL_ASSERT(__rank < __nn); _DifferenceType __ns = new _DifferenceType[__m]; _DifferenceType* __a = new _DifferenceType[__m]; _DifferenceType* __b = new _DifferenceType[__m]; _DifferenceType __l; __ns[0] = std::distance(__begin_seqs[0].first, __begin_seqs[0].second); __nmax = __ns[0]; for (_SeqNumber __i = 0; __i < __m; __i++) { __ns[__i] = std::distance(__begin_seqs[__i].first, __begin_seqs[__i].second); __nmax = std::max(__nmax, __ns[__i]); } __r = __rd_log2(__nmax) + 1; // Pad all lists to this length, at least as long as any ns[__i], // equality iff __nmax = 2^__k - 1. __l = (1ULL << __r) - 1; for (_SeqNumber __i = 0; __i < __m; __i++) { __a[__i] = 0; __b[__i] = __l; } __n = __l / 2; // Invariants: // 0 <= __a[__i] <= __ns[__i], 0 <= __b[__i] <= __l #define __S(__i) (__begin_seqs[__i].first) // Initial partition. std::vector<std::pair<_ValueType, _SeqNumber> > __sample; for (_SeqNumber __i = 0; __i < __m; __i++) if (__n < __ns[__i]) //__sequence long enough __sample.push_back(std::make_pair(__S(__i)[__n], __i)); __gnu_sequential::sort(__sample.begin(), __sample.end(), __lcomp); for (_SeqNumber __i = 0; __i < __m; __i++) //conceptual infinity if (__n >= __ns[__i]) //__sequence too short, conceptual infinity __sample.push_back( std::make_pair(__S(__i)[0] /__dummy element/, __i)); _DifferenceType __localrank = __rank / __l; _SeqNumber __j; for (__j = 0; __j < __localrank && ((__n + 1) <= __ns[__sample[__j].second]); ++__j) __a[__sample[__j].second] += __n + 1; for (; __j < __m; __j++) __b[__sample[__j].second] -= __n + 1; // Further refinement. while (__n > 0) { __n /= 2; _SeqNumber __lmax_seq = -1; // to avoid warning const _ValueType* __lmax = 0; // impossible to avoid the warning? for (_SeqNumber __i = 0; __i < __m; __i++) { if (__a[__i] > 0) { if (!__lmax) { __lmax = &(__S(__i)[__a[__i] - 1]); __lmax_seq = __i; } else { // Max, favor rear sequences. if (!__comp(__S(__i)[__a[__i] - 1], __lmax)) { __lmax = &(__S(__i)[__a[__i] - 1]); __lmax_seq = __i; } } } } _SeqNumber __i; for (__i = 0; __i < __m; __i++) { _DifferenceType __middle = (__b[__i] + __a[__i]) / 2; if (__lmax && __middle < __ns[__i] && __lcomp(std::make_pair(__S(__i)[__middle], __i), std::make_pair(__lmax, __lmax_seq))) __a[__i] = std::min(__a[__i] + __n + 1, __ns[__i]); else __b[__i] -= __n + 1; } _DifferenceType __leftsize = 0; for (_SeqNumber __i = 0; __i < __m; __i++) __leftsize += __a[__i] / (__n + 1); _DifferenceType __skew = __rank / (__n + 1) - __leftsize; if (__skew > 0) { // Move to the left, find smallest. std::priority_queue<std::pair<_ValueType, _SeqNumber>, std::vector<std::pair<_ValueType, _SeqNumber> >, _LexicographicReverse<_ValueType, _SeqNumber, _Compare> > __pq(__lrcomp); for (_SeqNumber __i = 0; __i < __m; __i++) if (__b[__i] < __ns[__i]) __pq.push(std::make_pair(__S(__i)[__b[__i]], __i)); for (; __skew != 0 && !__pq.empty(); --__skew) { _SeqNumber __source = __pq.top().second; __pq.pop(); __a[__source] = std::min(__a[__source] + __n + 1, __ns[__source]); __b[__source] += __n + 1; if (__b[__source] < __ns[__source]) __pq.push( std::make_pair(__S(__source)[__b[__source]], __source)); } } else if (__skew < 0) { // Move to the right, find greatest. std::priority_queue<std::pair<_ValueType, _SeqNumber>, std::vector<std::pair<_ValueType, _SeqNumber> >, _Lexicographic<_ValueType, _SeqNumber, _Compare> > __pq(__lcomp); for (_SeqNumber __i = 0; __i < __m; __i++) if (__a[__i] > 0) __pq.push(std::make_pair(__S(__i)[__a[__i] - 1], __i)); for (; __skew != 0; ++__skew) { _SeqNumber __source = __pq.top().second; __pq.pop(); __a[__source] -= __n + 1; __b[__source] -= __n + 1; if (__a[__source] > 0) __pq.push(std::make_pair( __S(__source)[__a[__source] - 1], __source)); } } } // Postconditions: // __a[__i] == __b[__i] in most cases, except when __a[__i] has been // clamped because of having reached the boundary // Now return the result, calculate the offset. // Compare the keys on both edges of the border. // Maximum of left edge, minimum of right edge. _ValueType* __maxleft = 0; _ValueType* __minright = 0; for (_SeqNumber __i = 0; __i < __m; __i++) { if (__a[__i] > 0) { if (!__maxleft) __maxleft = &(__S(__i)[__a[__i] - 1]); else { // Max, favor rear sequences. if (!__comp(__S(__i)[__a[__i] - 1], __maxleft)) __maxleft = &(__S(__i)[__a[__i] - 1]); } } if (__b[__i] < __ns[__i]) { if (!__minright) __minright = &(__S(__i)[__b[__i]]); else { // Min, favor fore sequences. if (__comp(__S(__i)[__b[__i]], __minright)) __minright = &(__S(__i)[__b[__i]]); } } } _SeqNumber __seq = 0; for (_SeqNumber __i = 0; __i < __m; __i++) __begin_offsets[__i] = __S(__i) + __a[__i]; delete[] __ns; delete[] __a; delete[] __b; } /** * @brief Selects the element at a certain global __rank from several * sorted sequences. * * The sequences are passed via a sequence of random-access * iterator pairs, none of the sequences may be empty. * @param __begin_seqs Begin of the sequence of iterator pairs. * @param __end_seqs End of the sequence of iterator pairs. * @param __rank The global rank to partition at. * @param __offset The rank of the selected element in the global * subsequence of elements equal to the selected element. If the * selected element is unique, this number is 0. * @param __comp The ordering functor, defaults to std::less. / template<typename _Tp, typename _RanSeqs, typename _RankType, typename _Compare> _Tp multiseq_selection(_RanSeqs __begin_seqs, _RanSeqs __end_seqs, _RankType __rank, _RankType& __offset, _Compare __comp = std::less<_Tp>()) { _GLIBCXX_CALL(__end_seqs - __begin_seqs) typedef typename std::iterator_traits<_RanSeqs>::value_type::first_type _It; typedef typename std::iterator_traits<_RanSeqs>::difference_type _SeqNumber; typedef typename std::iterator_traits<_It>::difference_type _DifferenceType; _Lexicographic<_Tp, _SeqNumber, _Compare> __lcomp(__comp); _LexicographicReverse<_Tp, _SeqNumber, _Compare> __lrcomp(__comp); // Number of sequences, number of elements in total (possibly // including padding). _DifferenceType __m = std::distance(__begin_seqs, __end_seqs); _DifferenceType __nn = 0; _DifferenceType __nmax, __n, __r; for (_SeqNumber __i = 0; __i < __m; __i++) __nn += std::distance(__begin_seqs[__i].first, __begin_seqs[__i].second); if (__m == 0 \|\| __nn == 0 \|\| __rank < 0 \|\| __rank >= __nn) { // result undefined if there is no data or __rank is outside bounds throw std::exception(); } _DifferenceType __ns = new _DifferenceType[__m]; _DifferenceType* __a = new _DifferenceType[__m]; _DifferenceType* __b = new _DifferenceType[__m]; _DifferenceType __l; __ns[0] = std::distance(__begin_seqs[0].first, __begin_seqs[0].second); __nmax = __ns[0]; for (_SeqNumber __i = 0; __i < __m; ++__i) { __ns[__i] = std::distance(__begin_seqs[__i].first, __begin_seqs[__i].second); __nmax = std::max(__nmax, __ns[__i]); } __r = __rd_log2(__nmax) + 1; // Pad all lists to this length, at least as long as any ns[__i], // equality iff __nmax = 2^__k - 1 __l = __round_up_to_pow2(__r) - 1; for (_SeqNumber __i = 0; __i < __m; ++__i) { __a[__i] = 0; __b[__i] = __l; } __n = __l / 2; // Invariants: // 0 <= __a[__i] <= __ns[__i], 0 <= __b[__i] <= __l #define __S(__i) (__begin_seqs[__i].first) // Initial partition. std::vector<std::pair<_Tp, _SeqNumber> > __sample; for (_SeqNumber __i = 0; __i < __m; __i++) if (__n < __ns[__i]) __sample.push_back(std::make_pair(__S(__i)[__n], __i)); __gnu_sequential::sort(__sample.begin(), __sample.end(), __lcomp, sequential_tag()); // Conceptual infinity. for (_SeqNumber __i = 0; __i < __m; __i++) if (__n >= __ns[__i]) __sample.push_back( std::make_pair(__S(__i)[0] /__dummy element/, __i)); _DifferenceType __localrank = __rank / __l; _SeqNumber __j; for (__j = 0; __j < __localrank && ((__n + 1) <= __ns[__sample[__j].second]); ++__j) __a[__sample[__j].second] += __n + 1; for (; __j < __m; ++__j) __b[__sample[__j].second] -= __n + 1; // Further refinement. while (__n > 0) { __n /= 2; const _Tp* __lmax = 0; for (_SeqNumber __i = 0; __i < __m; ++__i) { if (__a[__i] > 0) { if (!__lmax) __lmax = &(__S(__i)[__a[__i] - 1]); else { if (__comp(__lmax, __S(__i)[__a[__i] - 1])) //max __lmax = &(__S(__i)[__a[__i] - 1]); } } } _SeqNumber __i; for (__i = 0; __i < __m; __i++) { _DifferenceType __middle = (__b[__i] + __a[__i]) / 2; if (__lmax && __middle < __ns[__i] && __comp(__S(__i)[__middle], __lmax)) __a[__i] = std::min(__a[__i] + __n + 1, __ns[__i]); else __b[__i] -= __n + 1; } _DifferenceType __leftsize = 0; for (_SeqNumber __i = 0; __i < __m; ++__i) __leftsize += __a[__i] / (__n + 1); _DifferenceType __skew = __rank / (__n + 1) - __leftsize; if (__skew > 0) { // Move to the left, find smallest. std::priority_queue<std::pair<_Tp, _SeqNumber>, std::vector<std::pair<_Tp, _SeqNumber> >, _LexicographicReverse<_Tp, _SeqNumber, _Compare> > __pq(__lrcomp); for (_SeqNumber __i = 0; __i < __m; ++__i) if (__b[__i] < __ns[__i]) __pq.push(std::make_pair(__S(__i)[__b[__i]], __i)); for (; __skew != 0 && !__pq.empty(); --__skew) { _SeqNumber __source = __pq.top().second; __pq.pop(); __a[__source] = std::min(__a[__source] + __n + 1, __ns[__source]); __b[__source] += __n + 1; if (__b[__source] < __ns[__source]) __pq.push( std::make_pair(__S(__source)[__b[__source]], __source)); } } else if (__skew < 0) { // Move to the right, find greatest. std::priority_queue<std::pair<_Tp, _SeqNumber>, std::vector<std::pair<_Tp, _SeqNumber> >, _Lexicographic<_Tp, _SeqNumber, _Compare> > __pq(__lcomp); for (_SeqNumber __i = 0; __i < __m; ++__i) if (__a[__i] > 0) __pq.push(std::make_pair(__S(__i)[__a[__i] - 1], __i)); for (; __skew != 0; ++__skew) { _SeqNumber __source = __pq.top().second; __pq.pop(); __a[__source] -= __n + 1; __b[__source] -= __n + 1; if (__a[__source] > 0) __pq.push(std::make_pair( __S(__source)[__a[__source] - 1], __source)); } } } // Postconditions: // __a[__i] == __b[__i] in most cases, except when __a[__i] has been // clamped because of having reached the boundary // Now return the result, calculate the offset. // Compare the keys on both edges of the border. // Maximum of left edge, minimum of right edge. bool __maxleftset = false, __minrightset = false; // Impossible to avoid the warning? _Tp __maxleft, __minright; for (_SeqNumber __i = 0; __i < __m; ++__i) { if (__a[__i] > 0) { if (!__maxleftset) { __maxleft = __S(__i)[__a[__i] - 1]; __maxleftset = true; } else { // Max. if (__comp(__maxleft, __S(__i)[__a[__i] - 1])) __maxleft = __S(__i)[__a[__i] - 1]; } } if (__b[__i] < __ns[__i]) { if (!__minrightset) { __minright = __S(__i)[__b[__i]]; __minrightset = true; } else { // Min. if (__comp(__S(__i)[__b[__i]], __minright)) __minright = __S(__i)[__b[__i]]; } } } // Minright is the __splitter, in any case. if (!__maxleftset \|\| __comp(__minright, __maxleft)) { // Good luck, everything is split unambiguously. __offset = 0; } else { // We have to calculate an offset. __offset = 0; for (_SeqNumber __i = 0; __i < __m; ++__i) { _DifferenceType lb = std::lower_bound(__S(__i), __S(__i) + __ns[__i], __minright, __comp) - __S(__i); __offset += __a[__i] - lb; } } delete[] __ns; delete[] __a; delete[] __b; return __minright; } } #undef __S #endif /* _GLIBCXX_PARALLEL_MULTISEQ_SELECTION_H */	21.56 KB	2025-09-15 15:41
📄 multiway_merge.h // -- C++ -- // Copyright (C) 2007-2021 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/multiway_merge.h * @brief Implementation of sequential and parallel multiway merge. * * Explanations on the high-speed merging routines in the appendix of * * P. Sanders. * Fast priority queues for cached memory. * ACM Journal of Experimental Algorithmics, 5, 2000. * * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler and Manuel Holtgrewe. #ifndef _GLIBCXX_PARALLEL_MULTIWAY_MERGE_H #define _GLIBCXX_PARALLEL_MULTIWAY_MERGE_H #include <vector> #include <bits/stl_algo.h> #include <parallel/features.h> #include <parallel/parallel.h> #include <parallel/losertree.h> #include <parallel/multiseq_selection.h> #if _GLIBCXX_PARALLEL_ASSERTIONS #include <parallel/checkers.h> #endif /* @brief Length of a sequence described by a pair of iterators. / #define _GLIBCXX_PARALLEL_LENGTH(__s) ((__s).second - (__s).first) namespace __gnu_parallel { template<typename _RAIter1, typename _RAIter2, typename _OutputIterator, typename _DifferenceTp, typename _Compare> _OutputIterator __merge_advance(_RAIter1&, _RAIter1, _RAIter2&, _RAIter2, _OutputIterator, _DifferenceTp, _Compare); /* @brief _Iterator wrapper supporting an implicit supremum at the end * of the sequence, dominating all comparisons. * * The implicit supremum comes with a performance cost. * * Deriving from _RAIter is not possible since * _RAIter need not be a class. / template<typename _RAIter, typename _Compare> class _GuardedIterator { private: /* @brief Current iterator __position. / _RAIter _M_current; /* @brief End iterator of the sequence. / _RAIter _M_end; /* @brief _Compare. / _Compare& __comp; public: /* @brief Constructor. Sets iterator to beginning of sequence. * @param __begin Begin iterator of sequence. * @param __end End iterator of sequence. * @param __comp Comparator provided for associated overloaded * compare operators. / _GuardedIterator(_RAIter __begin, _RAIter __end, _Compare& __comp) : _M_current(__begin), _M_end(__end), __comp(__comp) { } /* @brief Pre-increment operator. * @return This. / _GuardedIterator<_RAIter, _Compare>& operator++() { ++_M_current; return this; } /** @brief Dereference operator. * @return Referenced element. / typename std::iterator_traits<_RAIter>::value_type& operator() const { return _M_current; } /* @brief Convert to wrapped iterator. * @return Wrapped iterator. / operator _RAIter() const { return _M_current; } /* @brief Compare two elements referenced by guarded iterators. * @param __bi1 First iterator. * @param __bi2 Second iterator. * @return @c true if less. / friend bool operator<(const _GuardedIterator<_RAIter, _Compare>& __bi1, const _GuardedIterator<_RAIter, _Compare>& __bi2) { if (__bi1._M_current == __bi1._M_end) // __bi1 is sup return __bi2._M_current == __bi2._M_end; // __bi2 is not sup if (__bi2._M_current == __bi2._M_end) // __bi2 is sup return true; return (__bi1.__comp)(__bi1, __bi2); // normal compare } /* @brief Compare two elements referenced by guarded iterators. * @param __bi1 First iterator. * @param __bi2 Second iterator. * @return @c True if less equal. / friend bool operator<=(const _GuardedIterator<_RAIter, _Compare>& __bi1, const _GuardedIterator<_RAIter, _Compare>& __bi2) { if (__bi2._M_current == __bi2._M_end) // __bi1 is sup return __bi1._M_current != __bi1._M_end; // __bi2 is not sup if (__bi1._M_current == __bi1._M_end) // __bi2 is sup return false; return !(__bi1.__comp)(__bi2, __bi1); // normal compare } }; template<typename _RAIter, typename _Compare> class _UnguardedIterator { private: /* @brief Current iterator __position. / _RAIter _M_current; /* @brief _Compare. / _Compare& __comp; public: /* @brief Constructor. Sets iterator to beginning of sequence. * @param __begin Begin iterator of sequence. * @param __end Unused, only for compatibility. * @param __comp Unused, only for compatibility. / _UnguardedIterator(_RAIter __begin, _RAIter / __end /, _Compare& __comp) : _M_current(__begin), __comp(__comp) { } /* @brief Pre-increment operator. * @return This. / _UnguardedIterator<_RAIter, _Compare>& operator++() { ++_M_current; return this; } /** @brief Dereference operator. * @return Referenced element. / typename std::iterator_traits<_RAIter>::value_type& operator() const { return _M_current; } /* @brief Convert to wrapped iterator. * @return Wrapped iterator. / operator _RAIter() const { return _M_current; } /* @brief Compare two elements referenced by unguarded iterators. * @param __bi1 First iterator. * @param __bi2 Second iterator. * @return @c true if less. / friend bool operator<(const _UnguardedIterator<_RAIter, _Compare>& __bi1, const _UnguardedIterator<_RAIter, _Compare>& __bi2) { // Normal compare. return (__bi1.__comp)(__bi1, __bi2); } /* @brief Compare two elements referenced by unguarded iterators. * @param __bi1 First iterator. * @param __bi2 Second iterator. * @return @c True if less equal. / friend bool operator<=(const _UnguardedIterator<_RAIter, _Compare>& __bi1, const _UnguardedIterator<_RAIter, _Compare>& __bi2) { // Normal compare. return !(__bi1.__comp)(__bi2, __bi1); } }; /* @brief Highly efficient 3-way merging procedure. * * Merging is done with the algorithm implementation described by Peter * Sanders. Basically, the idea is to minimize the number of necessary * comparison after merging an element. The implementation trick * that makes this fast is that the order of the sequences is stored * in the instruction pointer (translated into labels in C++). * * This works well for merging up to 4 sequences. * * Note that making the merging stable does @a not come at a * performance hit. * * Whether the merging is done guarded or unguarded is selected by the * used iterator class. * * @param __seqs_begin Begin iterator of iterator pair input sequence. * @param __seqs_end End iterator of iterator pair input sequence. * @param __target Begin iterator of output sequence. * @param __comp Comparator. * @param __length Maximum length to merge, less equal than the * total number of elements available. * * @return End iterator of output sequence. / template<template<typename _RAI, typename _Cp> class iterator, typename _RAIterIterator, typename _RAIter3, typename _DifferenceTp, typename _Compare> _RAIter3 multiway_merge_3_variant(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, _DifferenceTp __length, _Compare __comp) { _GLIBCXX_CALL(__length); typedef _DifferenceTp _DifferenceType; typedef typename std::iterator_traits<_RAIterIterator> ::value_type::first_type _RAIter1; typedef typename std::iterator_traits<_RAIter1>::value_type _ValueType; if (__length == 0) return __target; #if _GLIBCXX_PARALLEL_ASSERTIONS _DifferenceTp __orig_length = __length; #endif iterator<_RAIter1, _Compare> __seq0(__seqs_begin[0].first, __seqs_begin[0].second, __comp), __seq1(__seqs_begin[1].first, __seqs_begin[1].second, __comp), __seq2(__seqs_begin[2].first, __seqs_begin[2].second, __comp); if (__seq0 <= __seq1) { if (__seq1 <= __seq2) goto __s012; else if (__seq2 < __seq0) goto __s201; else goto __s021; } else { if (__seq1 <= __seq2) { if (__seq0 <= __seq2) goto __s102; else goto __s120; } else goto __s210; } #define _GLIBCXX_PARALLEL_MERGE_3_CASE(__a, __b, __c, __c0, __c1) \ __s ## __a ## __b ## __c : \ __target = __seq ## __a; \ ++__target; \ --__length; \ ++__seq ## __a; \ if (__length == 0) goto __finish; \ if (__seq ## __a __c0 __seq ## __b) goto __s ## __a ## __b ## __c; \ if (__seq ## __a __c1 __seq ## __c) goto __s ## __b ## __a ## __c; \ goto __s ## __b ## __c ## __a; _GLIBCXX_PARALLEL_MERGE_3_CASE(0, 1, 2, <=, <=); _GLIBCXX_PARALLEL_MERGE_3_CASE(1, 2, 0, <=, < ); _GLIBCXX_PARALLEL_MERGE_3_CASE(2, 0, 1, < , < ); _GLIBCXX_PARALLEL_MERGE_3_CASE(1, 0, 2, < , <=); _GLIBCXX_PARALLEL_MERGE_3_CASE(0, 2, 1, <=, <=); _GLIBCXX_PARALLEL_MERGE_3_CASE(2, 1, 0, < , < ); #undef _GLIBCXX_PARALLEL_MERGE_3_CASE __finish: ; #if _GLIBCXX_PARALLEL_ASSERTIONS _GLIBCXX_PARALLEL_ASSERT( ((_RAIter1)__seq0 - __seqs_begin[0].first) + ((_RAIter1)__seq1 - __seqs_begin[1].first) + ((_RAIter1)__seq2 - __seqs_begin[2].first) == __orig_length); #endif __seqs_begin[0].first = __seq0; __seqs_begin[1].first = __seq1; __seqs_begin[2].first = __seq2; return __target; } /* * @brief Highly efficient 4-way merging procedure. * * Merging is done with the algorithm implementation described by Peter * Sanders. Basically, the idea is to minimize the number of necessary * comparison after merging an element. The implementation trick * that makes this fast is that the order of the sequences is stored * in the instruction pointer (translated into goto labels in C++). * * This works well for merging up to 4 sequences. * * Note that making the merging stable does @a not come at a * performance hit. * * Whether the merging is done guarded or unguarded is selected by the * used iterator class. * * @param __seqs_begin Begin iterator of iterator pair input sequence. * @param __seqs_end End iterator of iterator pair input sequence. * @param __target Begin iterator of output sequence. * @param __comp Comparator. * @param __length Maximum length to merge, less equal than the * total number of elements available. * * @return End iterator of output sequence. / template<template<typename _RAI, typename _Cp> class iterator, typename _RAIterIterator, typename _RAIter3, typename _DifferenceTp, typename _Compare> _RAIter3 multiway_merge_4_variant(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, _DifferenceTp __length, _Compare __comp) { _GLIBCXX_CALL(__length); typedef _DifferenceTp _DifferenceType; typedef typename std::iterator_traits<_RAIterIterator> ::value_type::first_type _RAIter1; typedef typename std::iterator_traits<_RAIter1>::value_type _ValueType; iterator<_RAIter1, _Compare> __seq0(__seqs_begin[0].first, __seqs_begin[0].second, __comp), __seq1(__seqs_begin[1].first, __seqs_begin[1].second, __comp), __seq2(__seqs_begin[2].first, __seqs_begin[2].second, __comp), __seq3(__seqs_begin[3].first, __seqs_begin[3].second, __comp); #define _GLIBCXX_PARALLEL_DECISION(__a, __b, __c, __d) { \ if (__seq ## __d < __seq ## __a) \ goto __s ## __d ## __a ## __b ## __c; \ if (__seq ## __d < __seq ## __b) \ goto __s ## __a ## __d ## __b ## __c; \ if (__seq ## __d < __seq ## __c) \ goto __s ## __a ## __b ## __d ## __c; \ goto __s ## __a ## __b ## __c ## __d; } if (__seq0 <= __seq1) { if (__seq1 <= __seq2) _GLIBCXX_PARALLEL_DECISION(0,1,2,3) else if (__seq2 < __seq0) _GLIBCXX_PARALLEL_DECISION(2,0,1,3) else _GLIBCXX_PARALLEL_DECISION(0,2,1,3) } else { if (__seq1 <= __seq2) { if (__seq0 <= __seq2) _GLIBCXX_PARALLEL_DECISION(1,0,2,3) else _GLIBCXX_PARALLEL_DECISION(1,2,0,3) } else _GLIBCXX_PARALLEL_DECISION(2,1,0,3) } #define _GLIBCXX_PARALLEL_MERGE_4_CASE(__a, __b, __c, __d, \ __c0, __c1, __c2) \ __s ## __a ## __b ## __c ## __d: \ if (__length == 0) goto __finish; \ __target = __seq ## __a; \ ++__target; \ --__length; \ ++__seq ## __a; \ if (__seq ## __a __c0 __seq ## __b) \ goto __s ## __a ## __b ## __c ## __d; \ if (__seq ## __a __c1 __seq ## __c) \ goto __s ## __b ## __a ## __c ## __d; \ if (__seq ## __a __c2 __seq ## __d) \ goto __s ## __b ## __c ## __a ## __d; \ goto __s ## __b ## __c ## __d ## __a; _GLIBCXX_PARALLEL_MERGE_4_CASE(0, 1, 2, 3, <=, <=, <=); _GLIBCXX_PARALLEL_MERGE_4_CASE(0, 1, 3, 2, <=, <=, <=); _GLIBCXX_PARALLEL_MERGE_4_CASE(0, 2, 1, 3, <=, <=, <=); _GLIBCXX_PARALLEL_MERGE_4_CASE(0, 2, 3, 1, <=, <=, <=); _GLIBCXX_PARALLEL_MERGE_4_CASE(0, 3, 1, 2, <=, <=, <=); _GLIBCXX_PARALLEL_MERGE_4_CASE(0, 3, 2, 1, <=, <=, <=); _GLIBCXX_PARALLEL_MERGE_4_CASE(1, 0, 2, 3, < , <=, <=); _GLIBCXX_PARALLEL_MERGE_4_CASE(1, 0, 3, 2, < , <=, <=); _GLIBCXX_PARALLEL_MERGE_4_CASE(1, 2, 0, 3, <=, < , <=); _GLIBCXX_PARALLEL_MERGE_4_CASE(1, 2, 3, 0, <=, <=, < ); _GLIBCXX_PARALLEL_MERGE_4_CASE(1, 3, 0, 2, <=, < , <=); _GLIBCXX_PARALLEL_MERGE_4_CASE(1, 3, 2, 0, <=, <=, < ); _GLIBCXX_PARALLEL_MERGE_4_CASE(2, 0, 1, 3, < , < , <=); _GLIBCXX_PARALLEL_MERGE_4_CASE(2, 0, 3, 1, < , <=, < ); _GLIBCXX_PARALLEL_MERGE_4_CASE(2, 1, 0, 3, < , < , <=); _GLIBCXX_PARALLEL_MERGE_4_CASE(2, 1, 3, 0, < , <=, < ); _GLIBCXX_PARALLEL_MERGE_4_CASE(2, 3, 0, 1, <=, < , < ); _GLIBCXX_PARALLEL_MERGE_4_CASE(2, 3, 1, 0, <=, < , < ); _GLIBCXX_PARALLEL_MERGE_4_CASE(3, 0, 1, 2, < , < , < ); _GLIBCXX_PARALLEL_MERGE_4_CASE(3, 0, 2, 1, < , < , < ); _GLIBCXX_PARALLEL_MERGE_4_CASE(3, 1, 0, 2, < , < , < ); _GLIBCXX_PARALLEL_MERGE_4_CASE(3, 1, 2, 0, < , < , < ); _GLIBCXX_PARALLEL_MERGE_4_CASE(3, 2, 0, 1, < , < , < ); _GLIBCXX_PARALLEL_MERGE_4_CASE(3, 2, 1, 0, < , < , < ); #undef _GLIBCXX_PARALLEL_MERGE_4_CASE #undef _GLIBCXX_PARALLEL_DECISION __finish: ; __seqs_begin[0].first = __seq0; __seqs_begin[1].first = __seq1; __seqs_begin[2].first = __seq2; __seqs_begin[3].first = __seq3; return __target; } /* @brief Multi-way merging procedure for a high branching factor, * guarded case. * * This merging variant uses a LoserTree class as selected by <tt>_LT</tt>. * * Stability is selected through the used LoserTree class <tt>_LT</tt>. * * At least one non-empty sequence is required. * * @param __seqs_begin Begin iterator of iterator pair input sequence. * @param __seqs_end End iterator of iterator pair input sequence. * @param __target Begin iterator of output sequence. * @param __comp Comparator. * @param __length Maximum length to merge, less equal than the * total number of elements available. * * @return End iterator of output sequence. / template<typename _LT, typename _RAIterIterator, typename _RAIter3, typename _DifferenceTp, typename _Compare> _RAIter3 multiway_merge_loser_tree(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, _DifferenceTp __length, _Compare __comp) { _GLIBCXX_CALL(__length) typedef _DifferenceTp _DifferenceType; typedef typename std::iterator_traits<_RAIterIterator> ::difference_type _SeqNumber; typedef typename std::iterator_traits<_RAIterIterator> ::value_type::first_type _RAIter1; typedef typename std::iterator_traits<_RAIter1>::value_type _ValueType; _SeqNumber __k = static_cast<_SeqNumber>(__seqs_end - __seqs_begin); _LT __lt(__k, __comp); // Default value for potentially non-default-constructible types. _ValueType __arbitrary_element = 0; for (_SeqNumber __t = 0; __t < __k; ++__t) { if(!__arbitrary_element && _GLIBCXX_PARALLEL_LENGTH(__seqs_begin[__t]) > 0) __arbitrary_element = &(__seqs_begin[__t].first); } for (_SeqNumber __t = 0; __t < __k; ++__t) { if (__seqs_begin[__t].first == __seqs_begin[__t].second) __lt.__insert_start(__arbitrary_element, __t, true); else __lt.__insert_start(__seqs_begin[__t].first, __t, false); } __lt.__init(); _SeqNumber __source; for (_DifferenceType __i = 0; __i < __length; ++__i) { //take out __source = __lt.__get_min_source(); (__target++) = (__seqs_begin[__source].first++); // Feed. if (__seqs_begin[__source].first == __seqs_begin[__source].second) __lt.__delete_min_insert(__arbitrary_element, true); else // Replace from same __source. __lt.__delete_min_insert(__seqs_begin[__source].first, false); } return __target; } /* @brief Multi-way merging procedure for a high branching factor, * unguarded case. * * Merging is done using the LoserTree class <tt>_LT</tt>. * * Stability is selected by the used LoserTrees. * * @pre No input will run out of elements during the merge. * * @param __seqs_begin Begin iterator of iterator pair input sequence. * @param __seqs_end End iterator of iterator pair input sequence. * @param __target Begin iterator of output sequence. * @param __comp Comparator. * @param __length Maximum length to merge, less equal than the * total number of elements available. * * @return End iterator of output sequence. / template<typename _LT, typename _RAIterIterator, typename _RAIter3, typename _DifferenceTp, typename _Compare> _RAIter3 multiway_merge_loser_tree_unguarded(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, const typename std::iterator_traits<typename std::iterator_traits< _RAIterIterator>::value_type::first_type>::value_type& __sentinel, _DifferenceTp __length, _Compare __comp) { _GLIBCXX_CALL(__length) typedef _DifferenceTp _DifferenceType; typedef typename std::iterator_traits<_RAIterIterator> ::difference_type _SeqNumber; typedef typename std::iterator_traits<_RAIterIterator> ::value_type::first_type _RAIter1; typedef typename std::iterator_traits<_RAIter1>::value_type _ValueType; _SeqNumber __k = __seqs_end - __seqs_begin; _LT __lt(__k, __sentinel, __comp); for (_SeqNumber __t = 0; __t < __k; ++__t) { #if _GLIBCXX_PARALLEL_ASSERTIONS _GLIBCXX_PARALLEL_ASSERT(__seqs_begin[__t].first != __seqs_begin[__t].second); #endif __lt.__insert_start(__seqs_begin[__t].first, __t, false); } __lt.__init(); _SeqNumber __source; #if _GLIBCXX_PARALLEL_ASSERTIONS _DifferenceType __i = 0; #endif _RAIter3 __target_end = __target + __length; while (__target < __target_end) { // Take out. __source = __lt.__get_min_source(); #if _GLIBCXX_PARALLEL_ASSERTIONS _GLIBCXX_PARALLEL_ASSERT(0 <= __source && __source < __k); _GLIBCXX_PARALLEL_ASSERT(__i == 0 \|\| !__comp((__seqs_begin[__source].first), (__target - 1))); #endif // Feed. (__target++) = (__seqs_begin[__source].first++); #if _GLIBCXX_PARALLEL_ASSERTIONS ++__i; #endif // Replace from same __source. __lt.__delete_min_insert(__seqs_begin[__source].first, false); } return __target; } /* @brief Multi-way merging procedure for a high branching factor, * requiring sentinels to exist. * * @tparam _UnguardedLoserTree Loser Tree variant to use for the unguarded * merging. * * @param __seqs_begin Begin iterator of iterator pair input sequence. * @param __seqs_end End iterator of iterator pair input sequence. * @param __target Begin iterator of output sequence. * @param __comp Comparator. * @param __length Maximum length to merge, less equal than the * total number of elements available. * * @return End iterator of output sequence. / template<typename _UnguardedLoserTree, typename _RAIterIterator, typename _RAIter3, typename _DifferenceTp, typename _Compare> _RAIter3 multiway_merge_loser_tree_sentinel(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, const typename std::iterator_traits<typename std::iterator_traits< _RAIterIterator>::value_type::first_type>::value_type& __sentinel, _DifferenceTp __length, _Compare __comp) { _GLIBCXX_CALL(__length) typedef _DifferenceTp _DifferenceType; typedef std::iterator_traits<_RAIterIterator> _TraitsType; typedef typename std::iterator_traits<_RAIterIterator> ::value_type::first_type _RAIter1; typedef typename std::iterator_traits<_RAIter1>::value_type _ValueType; _RAIter3 __target_end; for (_RAIterIterator __s = __seqs_begin; __s != __seqs_end; ++__s) // Move the sequence ends to the sentinel. This has the // effect that the sentinel appears to be within the sequence. Then, // we can use the unguarded variant if we merge out as many // non-sentinel elements as we have. ++((__s).second); __target_end = multiway_merge_loser_tree_unguarded<_UnguardedLoserTree> (__seqs_begin, __seqs_end, __target, __sentinel, __length, __comp); #if _GLIBCXX_PARALLEL_ASSERTIONS _GLIBCXX_PARALLEL_ASSERT(__target_end == __target + __length); _GLIBCXX_PARALLEL_ASSERT(__is_sorted(__target, __target_end, __comp)); #endif // Restore the sequence ends so the sentinels are not contained in the // sequence any more (see comment in loop above). for (_RAIterIterator __s = __seqs_begin; __s != __seqs_end; ++__s) --((__s).second); return __target_end; } /* * @brief Traits for determining whether the loser tree should * use pointers or copies. * * The field "_M_use_pointer" is used to determine whether to use pointers * in he loser trees or whether to copy the values into the loser tree. * * The default behavior is to use pointers if the data type is 4 times as * big as the pointer to it. * * Specialize for your data type to customize the behavior. * * Example: * * template<> * struct _LoserTreeTraits<int> * { static const bool _M_use_pointer = false; }; * * template<> * struct _LoserTreeTraits<heavyweight_type> * { static const bool _M_use_pointer = true; }; * * @param _Tp type to give the loser tree traits for. / template <typename _Tp> struct _LoserTreeTraits { /* * @brief True iff to use pointers instead of values in loser trees. * * The default behavior is to use pointers if the data type is four * times as big as the pointer to it. / static const bool _M_use_pointer = (sizeof(_Tp) > 4 sizeof(_Tp)); }; /* * @brief Switch for 3-way merging with __sentinels turned off. * * Note that 3-way merging is always stable! / template<bool __sentinels /default == false/, typename _RAIterIterator, typename _RAIter3, typename _DifferenceTp, typename _Compare> struct __multiway_merge_3_variant_sentinel_switch { _RAIter3 operator()(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, _DifferenceTp __length, _Compare __comp) { return multiway_merge_3_variant<_GuardedIterator> (__seqs_begin, __seqs_end, __target, __length, __comp); } }; /* * @brief Switch for 3-way merging with __sentinels turned on. * * Note that 3-way merging is always stable! / template<typename _RAIterIterator, typename _RAIter3, typename _DifferenceTp, typename _Compare> struct __multiway_merge_3_variant_sentinel_switch<true, _RAIterIterator, _RAIter3, _DifferenceTp, _Compare> { _RAIter3 operator()(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, _DifferenceTp __length, _Compare __comp) { return multiway_merge_3_variant<_UnguardedIterator> (__seqs_begin, __seqs_end, __target, __length, __comp); } }; /* * @brief Switch for 4-way merging with __sentinels turned off. * * Note that 4-way merging is always stable! / template<bool __sentinels /default == false/, typename _RAIterIterator, typename _RAIter3, typename _DifferenceTp, typename _Compare> struct __multiway_merge_4_variant_sentinel_switch { _RAIter3 operator()(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, _DifferenceTp __length, _Compare __comp) { return multiway_merge_4_variant<_GuardedIterator> (__seqs_begin, __seqs_end, __target, __length, __comp); } }; /* * @brief Switch for 4-way merging with __sentinels turned on. * * Note that 4-way merging is always stable! / template<typename _RAIterIterator, typename _RAIter3, typename _DifferenceTp, typename _Compare> struct __multiway_merge_4_variant_sentinel_switch<true, _RAIterIterator, _RAIter3, _DifferenceTp, _Compare> { _RAIter3 operator()(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, _DifferenceTp __length, _Compare __comp) { return multiway_merge_4_variant<_UnguardedIterator> (__seqs_begin, __seqs_end, __target, __length, __comp); } }; /* * @brief Switch for k-way merging with __sentinels turned on. / template<bool __sentinels, bool __stable, typename _RAIterIterator, typename _RAIter3, typename _DifferenceTp, typename _Compare> struct __multiway_merge_k_variant_sentinel_switch { _RAIter3 operator()(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, const typename std::iterator_traits<typename std::iterator_traits< _RAIterIterator>::value_type::first_type>::value_type& __sentinel, _DifferenceTp __length, _Compare __comp) { typedef typename std::iterator_traits<_RAIterIterator> ::value_type::first_type _RAIter1; typedef typename std::iterator_traits<_RAIter1>::value_type _ValueType; return multiway_merge_loser_tree_sentinel< typename __gnu_cxx::__conditional_type< _LoserTreeTraits<_ValueType>::_M_use_pointer, _LoserTreePointerUnguarded<__stable, _ValueType, _Compare>, _LoserTreeUnguarded<__stable, _ValueType, _Compare> >::__type> (__seqs_begin, __seqs_end, __target, __sentinel, __length, __comp); } }; /* * @brief Switch for k-way merging with __sentinels turned off. / template<bool __stable, typename _RAIterIterator, typename _RAIter3, typename _DifferenceTp, typename _Compare> struct __multiway_merge_k_variant_sentinel_switch<false, __stable, _RAIterIterator, _RAIter3, _DifferenceTp, _Compare> { _RAIter3 operator()(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, const typename std::iterator_traits<typename std::iterator_traits< _RAIterIterator>::value_type::first_type>::value_type& __sentinel, _DifferenceTp __length, _Compare __comp) { typedef typename std::iterator_traits<_RAIterIterator> ::value_type::first_type _RAIter1; typedef typename std::iterator_traits<_RAIter1>::value_type _ValueType; return multiway_merge_loser_tree< typename __gnu_cxx::__conditional_type< _LoserTreeTraits<_ValueType>::_M_use_pointer, _LoserTreePointer<__stable, _ValueType, _Compare>, _LoserTree<__stable, _ValueType, _Compare> >::__type >(__seqs_begin, __seqs_end, __target, __length, __comp); } }; /* @brief Sequential multi-way merging switch. * * The _GLIBCXX_PARALLEL_DECISION is based on the branching factor and * runtime settings. * @param __seqs_begin Begin iterator of iterator pair input sequence. * @param __seqs_end End iterator of iterator pair input sequence. * @param __target Begin iterator of output sequence. * @param __comp Comparator. * @param __length Maximum length to merge, possibly larger than the * number of elements available. * @param __sentinel The sequences have __a __sentinel element. * @return End iterator of output sequence. / template<bool __stable, bool __sentinels, typename _RAIterIterator, typename _RAIter3, typename _DifferenceTp, typename _Compare> _RAIter3 __sequential_multiway_merge(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, const typename std::iterator_traits<typename std::iterator_traits< _RAIterIterator>::value_type::first_type>::value_type& __sentinel, _DifferenceTp __length, _Compare __comp) { _GLIBCXX_CALL(__length) typedef _DifferenceTp _DifferenceType; typedef typename std::iterator_traits<_RAIterIterator> ::difference_type _SeqNumber; typedef typename std::iterator_traits<_RAIterIterator> ::value_type::first_type _RAIter1; typedef typename std::iterator_traits<_RAIter1>::value_type _ValueType; #if _GLIBCXX_PARALLEL_ASSERTIONS for (_RAIterIterator __s = __seqs_begin; __s != __seqs_end; ++__s) { _GLIBCXX_PARALLEL_ASSERT(__is_sorted((__s).first, (__s).second, __comp)); } #endif _DifferenceTp __total_length = 0; for (_RAIterIterator __s = __seqs_begin; __s != __seqs_end; ++__s) __total_length += _GLIBCXX_PARALLEL_LENGTH(__s); __length = std::min<_DifferenceTp>(__length, __total_length); if(__length == 0) return __target; _RAIter3 __return_target = __target; _SeqNumber __k = static_cast<_SeqNumber>(__seqs_end - __seqs_begin); switch (__k) { case 0: break; case 1: __return_target = std::copy(__seqs_begin[0].first, __seqs_begin[0].first + __length, __target); __seqs_begin[0].first += __length; break; case 2: __return_target = __merge_advance(__seqs_begin[0].first, __seqs_begin[0].second, __seqs_begin[1].first, __seqs_begin[1].second, __target, __length, __comp); break; case 3: __return_target = __multiway_merge_3_variant_sentinel_switch <__sentinels, _RAIterIterator, _RAIter3, _DifferenceTp, _Compare>() (__seqs_begin, __seqs_end, __target, __length, __comp); break; case 4: __return_target = __multiway_merge_4_variant_sentinel_switch <__sentinels, _RAIterIterator, _RAIter3, _DifferenceTp, _Compare>() (__seqs_begin, __seqs_end, __target, __length, __comp); break; default: __return_target = __multiway_merge_k_variant_sentinel_switch <__sentinels, __stable, _RAIterIterator, _RAIter3, _DifferenceTp, _Compare>() (__seqs_begin, __seqs_end, __target, __sentinel, __length, __comp); break; } #if _GLIBCXX_PARALLEL_ASSERTIONS _GLIBCXX_PARALLEL_ASSERT( __is_sorted(__target, __target + __length, __comp)); #endif return __return_target; } /** * @brief Stable sorting functor. * * Used to reduce code instanciation in multiway_merge_sampling_splitting. / template<bool __stable, class _RAIter, class _StrictWeakOrdering> struct _SamplingSorter { void operator()(_RAIter __first, _RAIter __last, _StrictWeakOrdering __comp) { __gnu_sequential::stable_sort(__first, __last, __comp); } }; /* * @brief Non-__stable sorting functor. * * Used to reduce code instantiation in multiway_merge_sampling_splitting. / template<class _RAIter, class _StrictWeakOrdering> struct _SamplingSorter<false, _RAIter, _StrictWeakOrdering> { void operator()(_RAIter __first, _RAIter __last, _StrictWeakOrdering __comp) { __gnu_sequential::sort(__first, __last, __comp); } }; /* * @brief Sampling based splitting for parallel multiway-merge routine. / template<bool __stable, typename _RAIterIterator, typename _Compare, typename _DifferenceType> void multiway_merge_sampling_splitting(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _DifferenceType __length, _DifferenceType __total_length, _Compare __comp, std::vector<std::pair<_DifferenceType, _DifferenceType> > __pieces) { typedef typename std::iterator_traits<_RAIterIterator> ::difference_type _SeqNumber; typedef typename std::iterator_traits<_RAIterIterator> ::value_type::first_type _RAIter1; typedef typename std::iterator_traits<_RAIter1>::value_type _ValueType; // __k sequences. const _SeqNumber __k = static_cast<_SeqNumber>(__seqs_end - __seqs_begin); const _ThreadIndex __num_threads = omp_get_num_threads(); const _DifferenceType __num_samples = __gnu_parallel::_Settings::get().merge_oversampling * __num_threads; _ValueType* __samples = static_cast<_ValueType> (::operator new(sizeof(_ValueType) __k * __num_samples)); // Sample. for (_SeqNumber __s = 0; __s < __k; ++__s) for (_DifferenceType __i = 0; __i < __num_samples; ++__i) { _DifferenceType sample_index = static_cast<_DifferenceType> (_GLIBCXX_PARALLEL_LENGTH(__seqs_begin[__s]) * (double(__i + 1) / (__num_samples + 1)) * (double(__length) / __total_length)); new(&(__samples[__s * __num_samples + __i])) _ValueType(__seqs_begin[__s].first[sample_index]); } // Sort stable or non-stable, depending on value of template parameter // "__stable". _SamplingSorter<__stable, _ValueType, _Compare>() (__samples, __samples + (__num_samples __k), __comp); for (_ThreadIndex __slab = 0; __slab < __num_threads; ++__slab) // For each slab / processor. for (_SeqNumber __seq = 0; __seq < __k; ++__seq) { // For each sequence. if (__slab > 0) __pieces[__slab][__seq].first = std::upper_bound (__seqs_begin[__seq].first, __seqs_begin[__seq].second, __samples[__num_samples * __k * __slab / __num_threads], __comp) - __seqs_begin[__seq].first; else // Absolute beginning. __pieces[__slab][__seq].first = 0; if ((__slab + 1) < __num_threads) __pieces[__slab][__seq].second = std::upper_bound (__seqs_begin[__seq].first, __seqs_begin[__seq].second, __samples[__num_samples * __k * (__slab + 1) / __num_threads], __comp) - __seqs_begin[__seq].first; else // Absolute end. __pieces[__slab][__seq].second = _GLIBCXX_PARALLEL_LENGTH(__seqs_begin[__seq]); } for (_SeqNumber __s = 0; __s < __k; ++__s) for (_DifferenceType __i = 0; __i < __num_samples; ++__i) __samples[__s * __num_samples + __i].~_ValueType(); ::operator delete(__samples); } /** * @brief Exact splitting for parallel multiway-merge routine. * * None of the passed sequences may be empty. / template<bool __stable, typename _RAIterIterator, typename _Compare, typename _DifferenceType> void multiway_merge_exact_splitting(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _DifferenceType __length, _DifferenceType __total_length, _Compare __comp, std::vector<std::pair<_DifferenceType, _DifferenceType> > __pieces) { typedef typename std::iterator_traits<_RAIterIterator> ::difference_type _SeqNumber; typedef typename std::iterator_traits<_RAIterIterator> ::value_type::first_type _RAIter1; const bool __tight = (__total_length == __length); // __k sequences. const _SeqNumber __k = __seqs_end - __seqs_begin; const _ThreadIndex __num_threads = omp_get_num_threads(); // (Settings::multiway_merge_splitting // == __gnu_parallel::_Settings::EXACT). std::vector<_RAIter1>* __offsets = new std::vector<_RAIter1>[__num_threads]; std::vector<std::pair<_RAIter1, _RAIter1> > __se(__k); copy(__seqs_begin, __seqs_end, __se.begin()); _DifferenceType* __borders = new _DifferenceType[__num_threads + 1]; __equally_split(__length, __num_threads, __borders); for (_ThreadIndex __s = 0; __s < (__num_threads - 1); ++__s) { __offsets[__s].resize(__k); multiseq_partition(__se.begin(), __se.end(), __borders[__s + 1], __offsets[__s].begin(), __comp); // Last one also needed and available. if (!__tight) { __offsets[__num_threads - 1].resize(__k); multiseq_partition(__se.begin(), __se.end(), _DifferenceType(__length), __offsets[__num_threads - 1].begin(), __comp); } } delete[] __borders; for (_ThreadIndex __slab = 0; __slab < __num_threads; ++__slab) { // For each slab / processor. for (_SeqNumber __seq = 0; __seq < __k; ++__seq) { // For each sequence. if (__slab == 0) { // Absolute beginning. __pieces[__slab][__seq].first = 0; } else __pieces[__slab][__seq].first = __pieces[__slab - 1][__seq].second; if (!__tight \|\| __slab < (__num_threads - 1)) __pieces[__slab][__seq].second = __offsets[__slab][__seq] - __seqs_begin[__seq].first; else { // __slab == __num_threads - 1 __pieces[__slab][__seq].second = _GLIBCXX_PARALLEL_LENGTH(__seqs_begin[__seq]); } } } delete[] __offsets; } /** @brief Parallel multi-way merge routine. * * The _GLIBCXX_PARALLEL_DECISION is based on the branching factor * and runtime settings. * * Must not be called if the number of sequences is 1. * * @tparam _Splitter functor to split input (either __exact or sampling based) * @tparam __stable Stable merging incurs a performance penalty. * @tparam __sentinel Ignored. * * @param __seqs_begin Begin iterator of iterator pair input sequence. * @param __seqs_end End iterator of iterator pair input sequence. * @param __target Begin iterator of output sequence. * @param __comp Comparator. * @param __length Maximum length to merge, possibly larger than the * number of elements available. * @return End iterator of output sequence. / template<bool __stable, bool __sentinels, typename _RAIterIterator, typename _RAIter3, typename _DifferenceTp, typename _Splitter, typename _Compare> _RAIter3 parallel_multiway_merge(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, _Splitter __splitter, _DifferenceTp __length, _Compare __comp, _ThreadIndex __num_threads) { #if _GLIBCXX_PARALLEL_ASSERTIONS _GLIBCXX_PARALLEL_ASSERT(__seqs_end - __seqs_begin > 1); #endif _GLIBCXX_CALL(__length) typedef _DifferenceTp _DifferenceType; typedef typename std::iterator_traits<_RAIterIterator> ::difference_type _SeqNumber; typedef typename std::iterator_traits<_RAIterIterator> ::value_type::first_type _RAIter1; typedef typename std::iterator_traits<_RAIter1>::value_type _ValueType; // Leave only non-empty sequences. typedef std::pair<_RAIter1, _RAIter1> seq_type; seq_type __ne_seqs = new seq_type[__seqs_end - __seqs_begin]; _SeqNumber __k = 0; _DifferenceType __total_length = 0; for (_RAIterIterator __raii = __seqs_begin; __raii != __seqs_end; ++__raii) { _DifferenceTp __seq_length = _GLIBCXX_PARALLEL_LENGTH(__raii); if(__seq_length > 0) { __total_length += __seq_length; __ne_seqs[__k++] = __raii; } } _GLIBCXX_CALL(__total_length) __length = std::min<_DifferenceTp>(__length, __total_length); if (__total_length == 0 \|\| __k == 0) { delete[] __ne_seqs; return __target; } std::vector<std::pair<_DifferenceType, _DifferenceType> >* __pieces; __num_threads = static_cast<_ThreadIndex> (std::min<_DifferenceType>(__num_threads, __total_length)); # pragma omp parallel num_threads (__num_threads) { # pragma omp single { __num_threads = omp_get_num_threads(); // Thread __t will have to merge pieces[__iam][0..__k - 1] __pieces = new std::vector< std::pair<_DifferenceType, _DifferenceType> >[__num_threads]; for (_ThreadIndex __s = 0; __s < __num_threads; ++__s) __pieces[__s].resize(__k); _DifferenceType __num_samples = __gnu_parallel::_Settings::get().merge_oversampling * __num_threads; __splitter(__ne_seqs, __ne_seqs + __k, __length, __total_length, __comp, __pieces); } //single _ThreadIndex __iam = omp_get_thread_num(); _DifferenceType __target_position = 0; for (_SeqNumber __c = 0; __c < __k; ++__c) __target_position += __pieces[__iam][__c].first; seq_type* __chunks = new seq_type[__k]; for (_SeqNumber __s = 0; __s < __k; ++__s) __chunks[__s] = std::make_pair(__ne_seqs[__s].first + __pieces[__iam][__s].first, __ne_seqs[__s].first + __pieces[__iam][__s].second); if(__length > __target_position) __sequential_multiway_merge<__stable, __sentinels> (__chunks, __chunks + __k, __target + __target_position, (__seqs_begin->second), __length - __target_position, __comp); delete[] __chunks; } // parallel #if _GLIBCXX_PARALLEL_ASSERTIONS _GLIBCXX_PARALLEL_ASSERT( __is_sorted(__target, __target + __length, __comp)); #endif __k = 0; // Update ends of sequences. for (_RAIterIterator __raii = __seqs_begin; __raii != __seqs_end; ++__raii) { _DifferenceTp __length = _GLIBCXX_PARALLEL_LENGTH(__raii); if(__length > 0) (__raii).first += __pieces[__num_threads - 1][__k++].second; } delete[] __pieces; delete[] __ne_seqs; return __target + __length; } /* * @brief Multiway Merge Frontend. * * Merge the sequences specified by seqs_begin and __seqs_end into * __target. __seqs_begin and __seqs_end must point to a sequence of * pairs. These pairs must contain an iterator to the beginning * of a sequence in their first entry and an iterator the _M_end of * the same sequence in their second entry. * * Ties are broken arbitrarily. See stable_multiway_merge for a variant * that breaks ties by sequence number but is slower. * * The first entries of the pairs (i.e. the begin iterators) will be moved * forward. * * The output sequence has to provide enough space for all elements * that are written to it. * * This function will merge the input sequences: * * - not stable * - parallel, depending on the input size and Settings * - using sampling for splitting * - not using sentinels * * Example: * * <pre> * int sequences[10][10]; * for (int __i = 0; __i < 10; ++__i) * for (int __j = 0; __i < 10; ++__j) * sequences[__i][__j] = __j; * * int __out[33]; * std::vector<std::pair<int> > seqs; for (int __i = 0; __i < 10; ++__i) * { seqs.push(std::make_pair<int>(sequences[__i], sequences[__i] + 10)) } * * multiway_merge(seqs.begin(), seqs.end(), __target, std::less<int>(), 33); * </pre> * * @see stable_multiway_merge * * @pre All input sequences must be sorted. * @pre Target must provide enough space to merge out length elements or * the number of elements in all sequences, whichever is smaller. * * @post [__target, return __value) contains merged __elements from the * input sequences. * @post return __value - __target = min(__length, number of elements in all * sequences). * * @tparam _RAIterPairIterator iterator over sequence * of pairs of iterators * @tparam _RAIterOut iterator over target sequence * @tparam _DifferenceTp difference type for the sequence * @tparam _Compare strict weak ordering type to compare elements * in sequences * * @param __seqs_begin __begin of sequence __sequence * @param __seqs_end _M_end of sequence __sequence * @param __target target sequence to merge to. * @param __comp strict weak ordering to use for element comparison. * @param __length Maximum length to merge, possibly larger than the * number of elements available. * * @return _M_end iterator of output sequence / // multiway_merge // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut multiway_merge(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, __gnu_parallel::sequential_tag) { typedef _DifferenceTp _DifferenceType; _GLIBCXX_CALL(__seqs_end - __seqs_begin) // catch special case: no sequences if (__seqs_begin == __seqs_end) return __target; // Execute multiway merge sequentially. return __sequential_multiway_merge </ __stable = / false, / __sentinels = / false> (__seqs_begin, __seqs_end, __target, (__seqs_begin->second), __length, __comp); } // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut multiway_merge(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, __gnu_parallel::exact_tag __tag) { typedef _DifferenceTp _DifferenceType; _GLIBCXX_CALL(__seqs_end - __seqs_begin) // catch special case: no sequences if (__seqs_begin == __seqs_end) return __target; // Execute merge; maybe parallel, depending on the number of merged // elements and the number of sequences and global thresholds in // Settings. if ((__seqs_end - __seqs_begin > 1) && _GLIBCXX_PARALLEL_CONDITION( ((__seqs_end - __seqs_begin) >= __gnu_parallel::_Settings::get().multiway_merge_minimal_k) && ((_SequenceIndex)__length >= __gnu_parallel::_Settings::get().multiway_merge_minimal_n))) return parallel_multiway_merge </* __stable = / false, / __sentinels = / false> (__seqs_begin, __seqs_end, __target, multiway_merge_exact_splitting</ __stable = / false, typename std::iterator_traits<_RAIterPairIterator> ::value_type, _Compare, _DifferenceTp>, static_cast<_DifferenceType>(__length), __comp, __tag.__get_num_threads()); else return __sequential_multiway_merge </* __stable = / false, / __sentinels = / false> (__seqs_begin, __seqs_end, __target, (__seqs_begin->second), __length, __comp); } // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut multiway_merge(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, __gnu_parallel::sampling_tag __tag) { typedef _DifferenceTp _DifferenceType; _GLIBCXX_CALL(__seqs_end - __seqs_begin) // catch special case: no sequences if (__seqs_begin == __seqs_end) return __target; // Execute merge; maybe parallel, depending on the number of merged // elements and the number of sequences and global thresholds in // Settings. if ((__seqs_end - __seqs_begin > 1) && _GLIBCXX_PARALLEL_CONDITION( ((__seqs_end - __seqs_begin) >= __gnu_parallel::_Settings::get().multiway_merge_minimal_k) && ((_SequenceIndex)__length >= __gnu_parallel::_Settings::get().multiway_merge_minimal_n))) return parallel_multiway_merge </* __stable = / false, / __sentinels = / false> (__seqs_begin, __seqs_end, __target, multiway_merge_exact_splitting</ __stable = / false, typename std::iterator_traits<_RAIterPairIterator> ::value_type, _Compare, _DifferenceTp>, static_cast<_DifferenceType>(__length), __comp, __tag.__get_num_threads()); else return __sequential_multiway_merge </* __stable = / false, / __sentinels = / false> (__seqs_begin, __seqs_end, __target, (__seqs_begin->second), __length, __comp); } // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut multiway_merge(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, parallel_tag __tag = parallel_tag(0)) { return multiway_merge(__seqs_begin, __seqs_end, __target, __length, __comp, exact_tag(__tag.__get_num_threads())); } // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut multiway_merge(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, default_parallel_tag __tag) { return multiway_merge(__seqs_begin, __seqs_end, __target, __length, __comp, exact_tag(__tag.__get_num_threads())); } // stable_multiway_merge // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut stable_multiway_merge(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, __gnu_parallel::sequential_tag) { typedef _DifferenceTp _DifferenceType; _GLIBCXX_CALL(__seqs_end - __seqs_begin) // catch special case: no sequences if (__seqs_begin == __seqs_end) return __target; // Execute multiway merge sequentially. return __sequential_multiway_merge </* __stable = / true, / __sentinels = / false> (__seqs_begin, __seqs_end, __target, (__seqs_begin->second), __length, __comp); } // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut stable_multiway_merge(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, __gnu_parallel::exact_tag __tag) { typedef _DifferenceTp _DifferenceType; _GLIBCXX_CALL(__seqs_end - __seqs_begin) // catch special case: no sequences if (__seqs_begin == __seqs_end) return __target; // Execute merge; maybe parallel, depending on the number of merged // elements and the number of sequences and global thresholds in // Settings. if ((__seqs_end - __seqs_begin > 1) && _GLIBCXX_PARALLEL_CONDITION( ((__seqs_end - __seqs_begin) >= __gnu_parallel::_Settings::get().multiway_merge_minimal_k) && ((_SequenceIndex)__length >= __gnu_parallel::_Settings::get().multiway_merge_minimal_n))) return parallel_multiway_merge </* __stable = / true, / __sentinels = / false> (__seqs_begin, __seqs_end, __target, multiway_merge_exact_splitting</ __stable = / true, typename std::iterator_traits<_RAIterPairIterator> ::value_type, _Compare, _DifferenceTp>, static_cast<_DifferenceType>(__length), __comp, __tag.__get_num_threads()); else return __sequential_multiway_merge </* __stable = / true, / __sentinels = / false> (__seqs_begin, __seqs_end, __target, (__seqs_begin->second), __length, __comp); } // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut stable_multiway_merge(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, sampling_tag __tag) { typedef _DifferenceTp _DifferenceType; _GLIBCXX_CALL(__seqs_end - __seqs_begin) // catch special case: no sequences if (__seqs_begin == __seqs_end) return __target; // Execute merge; maybe parallel, depending on the number of merged // elements and the number of sequences and global thresholds in // Settings. if ((__seqs_end - __seqs_begin > 1) && _GLIBCXX_PARALLEL_CONDITION( ((__seqs_end - __seqs_begin) >= __gnu_parallel::_Settings::get().multiway_merge_minimal_k) && ((_SequenceIndex)__length >= __gnu_parallel::_Settings::get().multiway_merge_minimal_n))) return parallel_multiway_merge </* __stable = / true, / __sentinels = / false> (__seqs_begin, __seqs_end, __target, multiway_merge_sampling_splitting</ __stable = / true, typename std::iterator_traits<_RAIterPairIterator> ::value_type, _Compare, _DifferenceTp>, static_cast<_DifferenceType>(__length), __comp, __tag.__get_num_threads()); else return __sequential_multiway_merge </* __stable = / true, / __sentinels = / false> (__seqs_begin, __seqs_end, __target, (__seqs_begin->second), __length, __comp); } // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut stable_multiway_merge(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, parallel_tag __tag = parallel_tag(0)) { return stable_multiway_merge (__seqs_begin, __seqs_end, __target, __length, __comp, exact_tag(__tag.__get_num_threads())); } // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut stable_multiway_merge(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, default_parallel_tag __tag) { return stable_multiway_merge (__seqs_begin, __seqs_end, __target, __length, __comp, exact_tag(__tag.__get_num_threads())); } /** * @brief Multiway Merge Frontend. * * Merge the sequences specified by seqs_begin and __seqs_end into * __target. __seqs_begin and __seqs_end must point to a sequence of * pairs. These pairs must contain an iterator to the beginning * of a sequence in their first entry and an iterator the _M_end of * the same sequence in their second entry. * * Ties are broken arbitrarily. See stable_multiway_merge for a variant * that breaks ties by sequence number but is slower. * * The first entries of the pairs (i.e. the begin iterators) will be moved * forward accordingly. * * The output sequence has to provide enough space for all elements * that are written to it. * * This function will merge the input sequences: * * - not stable * - parallel, depending on the input size and Settings * - using sampling for splitting * - using sentinels * * You have to take care that the element the _M_end iterator points to is * readable and contains a value that is greater than any other non-sentinel * value in all sequences. * * Example: * * <pre> * int sequences[10][11]; * for (int __i = 0; __i < 10; ++__i) * for (int __j = 0; __i < 11; ++__j) * sequences[__i][__j] = __j; // __last one is sentinel! * * int __out[33]; * std::vector<std::pair<int> > seqs; for (int __i = 0; __i < 10; ++__i) * { seqs.push(std::make_pair<int>(sequences[__i], sequences[__i] + 10)) } * * multiway_merge(seqs.begin(), seqs.end(), __target, std::less<int>(), 33); * </pre> * * @pre All input sequences must be sorted. * @pre Target must provide enough space to merge out length elements or * the number of elements in all sequences, whichever is smaller. * @pre For each @c __i, @c __seqs_begin[__i].second must be the end * marker of the sequence, but also reference the one more __sentinel * element. * * @post [__target, return __value) contains merged __elements from the * input sequences. * @post return __value - __target = min(__length, number of elements in all * sequences). * * @see stable_multiway_merge_sentinels * * @tparam _RAIterPairIterator iterator over sequence * of pairs of iterators * @tparam _RAIterOut iterator over target sequence * @tparam _DifferenceTp difference type for the sequence * @tparam _Compare strict weak ordering type to compare elements * in sequences * * @param __seqs_begin __begin of sequence __sequence * @param __seqs_end _M_end of sequence __sequence * @param __target target sequence to merge to. * @param __comp strict weak ordering to use for element comparison. * @param __length Maximum length to merge, possibly larger than the * number of elements available. * * @return _M_end iterator of output sequence / // multiway_merge_sentinels // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut multiway_merge_sentinels(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, __gnu_parallel::sequential_tag) { typedef _DifferenceTp _DifferenceType; _GLIBCXX_CALL(__seqs_end - __seqs_begin) // catch special case: no sequences if (__seqs_begin == __seqs_end) return __target; // Execute multiway merge sequentially. return __sequential_multiway_merge </ __stable = / false, / __sentinels = / true> (__seqs_begin, __seqs_end, __target, (__seqs_begin->second), __length, __comp); } // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut multiway_merge_sentinels(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, __gnu_parallel::exact_tag __tag) { typedef _DifferenceTp _DifferenceType; _GLIBCXX_CALL(__seqs_end - __seqs_begin) // catch special case: no sequences if (__seqs_begin == __seqs_end) return __target; // Execute merge; maybe parallel, depending on the number of merged // elements and the number of sequences and global thresholds in // Settings. if ((__seqs_end - __seqs_begin > 1) && _GLIBCXX_PARALLEL_CONDITION( ((__seqs_end - __seqs_begin) >= __gnu_parallel::_Settings::get().multiway_merge_minimal_k) && ((_SequenceIndex)__length >= __gnu_parallel::_Settings::get().multiway_merge_minimal_n))) return parallel_multiway_merge </* __stable = / false, / __sentinels = / true> (__seqs_begin, __seqs_end, __target, multiway_merge_exact_splitting</ __stable = / false, typename std::iterator_traits<_RAIterPairIterator> ::value_type, _Compare, _DifferenceTp>, static_cast<_DifferenceType>(__length), __comp, __tag.__get_num_threads()); else return __sequential_multiway_merge </* __stable = / false, / __sentinels = / true> (__seqs_begin, __seqs_end, __target, (__seqs_begin->second), __length, __comp); } // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut multiway_merge_sentinels(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, sampling_tag __tag) { typedef _DifferenceTp _DifferenceType; _GLIBCXX_CALL(__seqs_end - __seqs_begin) // catch special case: no sequences if (__seqs_begin == __seqs_end) return __target; // Execute merge; maybe parallel, depending on the number of merged // elements and the number of sequences and global thresholds in // Settings. if ((__seqs_end - __seqs_begin > 1) && _GLIBCXX_PARALLEL_CONDITION( ((__seqs_end - __seqs_begin) >= __gnu_parallel::_Settings::get().multiway_merge_minimal_k) && ((_SequenceIndex)__length >= __gnu_parallel::_Settings::get().multiway_merge_minimal_n))) return parallel_multiway_merge </* __stable = / false, / __sentinels = / true> (__seqs_begin, __seqs_end, __target, multiway_merge_sampling_splitting</ __stable = / false, typename std::iterator_traits<_RAIterPairIterator> ::value_type, _Compare, _DifferenceTp>, static_cast<_DifferenceType>(__length), __comp, __tag.__get_num_threads()); else return __sequential_multiway_merge </* __stable = /false, / __sentinels = / true>( __seqs_begin, __seqs_end, __target, (__seqs_begin->second), __length, __comp); } // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut multiway_merge_sentinels(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, parallel_tag __tag = parallel_tag(0)) { return multiway_merge_sentinels (__seqs_begin, __seqs_end, __target, __length, __comp, exact_tag(__tag.__get_num_threads())); } // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut multiway_merge_sentinels(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, default_parallel_tag __tag) { return multiway_merge_sentinels (__seqs_begin, __seqs_end, __target, __length, __comp, exact_tag(__tag.__get_num_threads())); } // stable_multiway_merge_sentinels // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut stable_multiway_merge_sentinels(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, __gnu_parallel::sequential_tag) { typedef _DifferenceTp _DifferenceType; _GLIBCXX_CALL(__seqs_end - __seqs_begin) // catch special case: no sequences if (__seqs_begin == __seqs_end) return __target; // Execute multiway merge sequentially. return __sequential_multiway_merge </* __stable = / true, / __sentinels = / true> (__seqs_begin, __seqs_end, __target, (__seqs_begin->second), __length, __comp); } // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut stable_multiway_merge_sentinels(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, __gnu_parallel::exact_tag __tag) { typedef _DifferenceTp _DifferenceType; _GLIBCXX_CALL(__seqs_end - __seqs_begin) // catch special case: no sequences if (__seqs_begin == __seqs_end) return __target; // Execute merge; maybe parallel, depending on the number of merged // elements and the number of sequences and global thresholds in // Settings. if ((__seqs_end - __seqs_begin > 1) && _GLIBCXX_PARALLEL_CONDITION( ((__seqs_end - __seqs_begin) >= __gnu_parallel::_Settings::get().multiway_merge_minimal_k) && ((_SequenceIndex)__length >= __gnu_parallel::_Settings::get().multiway_merge_minimal_n))) return parallel_multiway_merge </* __stable = / true, / __sentinels = / true> (__seqs_begin, __seqs_end, __target, multiway_merge_exact_splitting</ __stable = / true, typename std::iterator_traits<_RAIterPairIterator> ::value_type, _Compare, _DifferenceTp>, static_cast<_DifferenceType>(__length), __comp, __tag.__get_num_threads()); else return __sequential_multiway_merge </* __stable = / true, / __sentinels = / true> (__seqs_begin, __seqs_end, __target, (__seqs_begin->second), __length, __comp); } // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut stable_multiway_merge_sentinels(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, sampling_tag __tag) { typedef _DifferenceTp _DifferenceType; _GLIBCXX_CALL(__seqs_end - __seqs_begin) // catch special case: no sequences if (__seqs_begin == __seqs_end) return __target; // Execute merge; maybe parallel, depending on the number of merged // elements and the number of sequences and global thresholds in // Settings. if ((__seqs_end - __seqs_begin > 1) && _GLIBCXX_PARALLEL_CONDITION( ((__seqs_end - __seqs_begin) >= __gnu_parallel::_Settings::get().multiway_merge_minimal_k) && ((_SequenceIndex)__length >= __gnu_parallel::_Settings::get().multiway_merge_minimal_n))) return parallel_multiway_merge </* __stable = / true, / __sentinels = / true> (__seqs_begin, __seqs_end, __target, multiway_merge_sampling_splitting</ __stable = / true, typename std::iterator_traits<_RAIterPairIterator> ::value_type, _Compare, _DifferenceTp>, static_cast<_DifferenceType>(__length), __comp, __tag.__get_num_threads()); else return __sequential_multiway_merge </* __stable = / true, / __sentinels = / true> (__seqs_begin, __seqs_end, __target, (__seqs_begin->second), __length, __comp); } // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut stable_multiway_merge_sentinels(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, parallel_tag __tag = parallel_tag(0)) { return stable_multiway_merge_sentinels (__seqs_begin, __seqs_end, __target, __length, __comp, exact_tag(__tag.__get_num_threads())); } // public interface template<typename _RAIterPairIterator, typename _RAIterOut, typename _DifferenceTp, typename _Compare> _RAIterOut stable_multiway_merge_sentinels(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare __comp, default_parallel_tag __tag) { return stable_multiway_merge_sentinels (__seqs_begin, __seqs_end, __target, __length, __comp, exact_tag(__tag.__get_num_threads())); } }; // namespace __gnu_parallel #endif /* _GLIBCXX_PARALLEL_MULTIWAY_MERGE_H */	68.96 KB	2025-09-15 15:41
📄 multiway_mergesort.h // -- C++ -- // Copyright (C) 2007-2021 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/multiway_mergesort.h * @brief Parallel multiway merge sort. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_MULTIWAY_MERGESORT_H #define _GLIBCXX_PARALLEL_MULTIWAY_MERGESORT_H 1 #include <vector> #include <parallel/basic_iterator.h> #include <bits/stl_algo.h> #include <parallel/parallel.h> #include <parallel/multiway_merge.h> namespace __gnu_parallel { /* @brief Subsequence description. / template<typename _DifferenceTp> struct _Piece { typedef _DifferenceTp _DifferenceType; /* @brief Begin of subsequence. / _DifferenceType _M_begin; /* @brief End of subsequence. / _DifferenceType _M_end; }; /* @brief Data accessed by all threads. * * PMWMS = parallel multiway mergesort / template<typename _RAIter> struct _PMWMSSortingData { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; /* @brief Number of threads involved. / _ThreadIndex _M_num_threads; /* @brief Input __begin. / _RAIter _M_source; /* @brief Start indices, per thread. / _DifferenceType _M_starts; /** @brief Storage in which to sort. / _ValueType* _M_temporary; /** @brief Samples. / _ValueType _M_samples; /** @brief Offsets to add to the found positions. / _DifferenceType _M_offsets; /** @brief Pieces of data to merge @c [thread][__sequence] / std::vector<_Piece<_DifferenceType> > _M_pieces; }; /** * @brief Select _M_samples from a sequence. * @param __sd Pointer to algorithm data. _Result will be placed in * @c __sd->_M_samples. * @param __num_samples Number of _M_samples to select. / template<typename _RAIter, typename _DifferenceTp> void __determine_samples(_PMWMSSortingData<_RAIter> __sd, _DifferenceTp __num_samples) { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef _DifferenceTp _DifferenceType; _ThreadIndex __iam = omp_get_thread_num(); _DifferenceType* __es = new _DifferenceType[__num_samples + 2]; __equally_split(__sd->_M_starts[__iam + 1] - __sd->_M_starts[__iam], __num_samples + 1, __es); for (_DifferenceType __i = 0; __i < __num_samples; ++__i) ::new(&(__sd->_M_samples[__iam * __num_samples + __i])) _ValueType(__sd->_M_source[__sd->_M_starts[__iam] + __es[__i + 1]]); delete[] __es; } /** @brief Split consistently. / template<bool __exact, typename _RAIter, typename _Compare, typename _SortingPlacesIterator> struct _SplitConsistently { }; /* @brief Split by exact splitting. / template<typename _RAIter, typename _Compare, typename _SortingPlacesIterator> struct _SplitConsistently<true, _RAIter, _Compare, _SortingPlacesIterator> { void operator()(const _ThreadIndex __iam, _PMWMSSortingData<_RAIter> __sd, _Compare& __comp, const typename std::iterator_traits<_RAIter>::difference_type __num_samples) const { # pragma omp barrier std::vector<std::pair<_SortingPlacesIterator, _SortingPlacesIterator> > __seqs(__sd->_M_num_threads); for (_ThreadIndex __s = 0; __s < __sd->_M_num_threads; __s++) __seqs[__s] = std::make_pair(__sd->_M_temporary[__s], __sd->_M_temporary[__s] + (__sd->_M_starts[__s + 1] - __sd->_M_starts[__s])); std::vector<_SortingPlacesIterator> __offsets(__sd->_M_num_threads); // if not last thread if (__iam < __sd->_M_num_threads - 1) multiseq_partition(__seqs.begin(), __seqs.end(), __sd->_M_starts[__iam + 1], __offsets.begin(), __comp); for (_ThreadIndex __seq = 0; __seq < __sd->_M_num_threads; __seq++) { // for each sequence if (__iam < (__sd->_M_num_threads - 1)) __sd->_M_pieces[__iam][__seq]._M_end = __offsets[__seq] - __seqs[__seq].first; else // very end of this sequence __sd->_M_pieces[__iam][__seq]._M_end = __sd->_M_starts[__seq + 1] - __sd->_M_starts[__seq]; } # pragma omp barrier for (_ThreadIndex __seq = 0; __seq < __sd->_M_num_threads; __seq++) { // For each sequence. if (__iam > 0) __sd->_M_pieces[__iam][__seq]._M_begin = __sd->_M_pieces[__iam - 1][__seq]._M_end; else // Absolute beginning. __sd->_M_pieces[__iam][__seq]._M_begin = 0; } } }; /** @brief Split by sampling. / template<typename _RAIter, typename _Compare, typename _SortingPlacesIterator> struct _SplitConsistently<false, _RAIter, _Compare, _SortingPlacesIterator> { void operator()(const _ThreadIndex __iam, _PMWMSSortingData<_RAIter> __sd, _Compare& __comp, const typename std::iterator_traits<_RAIter>::difference_type __num_samples) const { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; __determine_samples(__sd, __num_samples); # pragma omp barrier # pragma omp single __gnu_sequential::sort(__sd->_M_samples, __sd->_M_samples + (__num_samples * __sd->_M_num_threads), __comp); # pragma omp barrier for (_ThreadIndex __s = 0; __s < __sd->_M_num_threads; ++__s) { // For each sequence. if (__num_samples * __iam > 0) __sd->_M_pieces[__iam][__s]._M_begin = std::lower_bound(__sd->_M_temporary[__s], __sd->_M_temporary[__s] + (__sd->_M_starts[__s + 1] - __sd->_M_starts[__s]), __sd->_M_samples[__num_samples * __iam], __comp) - __sd->_M_temporary[__s]; else // Absolute beginning. __sd->_M_pieces[__iam][__s]._M_begin = 0; if ((__num_samples * (__iam + 1)) < (__num_samples * __sd->_M_num_threads)) __sd->_M_pieces[__iam][__s]._M_end = std::lower_bound(__sd->_M_temporary[__s], __sd->_M_temporary[__s] + (__sd->_M_starts[__s + 1] - __sd->_M_starts[__s]), __sd->_M_samples[__num_samples * (__iam + 1)], __comp) - __sd->_M_temporary[__s]; else // Absolute end. __sd->_M_pieces[__iam][__s]._M_end = (__sd->_M_starts[__s + 1] - __sd->_M_starts[__s]); } } }; template<bool __stable, typename _RAIter, typename _Compare> struct __possibly_stable_sort { }; template<typename _RAIter, typename _Compare> struct __possibly_stable_sort<true, _RAIter, _Compare> { void operator()(const _RAIter& __begin, const _RAIter& __end, _Compare& __comp) const { __gnu_sequential::stable_sort(__begin, __end, __comp); } }; template<typename _RAIter, typename _Compare> struct __possibly_stable_sort<false, _RAIter, _Compare> { void operator()(const _RAIter __begin, const _RAIter __end, _Compare& __comp) const { __gnu_sequential::sort(__begin, __end, __comp); } }; template<bool __stable, typename _Seq_RAIter, typename _RAIter, typename _Compare, typename _DiffType> struct __possibly_stable_multiway_merge { }; template<typename _Seq_RAIter, typename _RAIter, typename _Compare, typename _DiffType> struct __possibly_stable_multiway_merge<true, _Seq_RAIter, _RAIter, _Compare, _DiffType> { void operator()(const _Seq_RAIter& __seqs_begin, const _Seq_RAIter& __seqs_end, const _RAIter& __target, _Compare& __comp, _DiffType __length_am) const { stable_multiway_merge(__seqs_begin, __seqs_end, __target, __length_am, __comp, sequential_tag()); } }; template<typename _Seq_RAIter, typename _RAIter, typename _Compare, typename _DiffType> struct __possibly_stable_multiway_merge<false, _Seq_RAIter, _RAIter, _Compare, _DiffType> { void operator()(const _Seq_RAIter& __seqs_begin, const _Seq_RAIter& __seqs_end, const _RAIter& __target, _Compare& __comp, _DiffType __length_am) const { multiway_merge(__seqs_begin, __seqs_end, __target, __length_am, __comp, sequential_tag()); } }; /** @brief PMWMS code executed by each thread. * @param __sd Pointer to algorithm data. * @param __comp Comparator. / template<bool __stable, bool __exact, typename _RAIter, typename _Compare> void parallel_sort_mwms_pu(_PMWMSSortingData<_RAIter> __sd, _Compare& __comp) { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; _ThreadIndex __iam = omp_get_thread_num(); // Length of this thread's chunk, before merging. _DifferenceType __length_local = __sd->_M_starts[__iam + 1] - __sd->_M_starts[__iam]; // Sort in temporary storage, leave space for sentinel. typedef _ValueType* _SortingPlacesIterator; __sd->_M_temporary[__iam] = static_cast<_ValueType>(::operator new(sizeof(_ValueType) (__length_local + 1))); // Copy there. std::uninitialized_copy(__sd->_M_source + __sd->_M_starts[__iam], __sd->_M_source + __sd->_M_starts[__iam] + __length_local, __sd->_M_temporary[__iam]); __possibly_stable_sort<__stable, _SortingPlacesIterator, _Compare>() (__sd->_M_temporary[__iam], __sd->_M_temporary[__iam] + __length_local, __comp); // Invariant: locally sorted subsequence in sd->_M_temporary[__iam], // __sd->_M_temporary[__iam] + __length_local. // No barrier here: Synchronization is done by the splitting routine. _DifferenceType __num_samples = _Settings::get().sort_mwms_oversampling * __sd->_M_num_threads - 1; _SplitConsistently<__exact, _RAIter, _Compare, _SortingPlacesIterator>() (__iam, __sd, __comp, __num_samples); // Offset from __target __begin, __length after merging. _DifferenceType __offset = 0, __length_am = 0; for (_ThreadIndex __s = 0; __s < __sd->_M_num_threads; __s++) { __length_am += (__sd->_M_pieces[__iam][__s]._M_end - __sd->_M_pieces[__iam][__s]._M_begin); __offset += __sd->_M_pieces[__iam][__s]._M_begin; } typedef std::vector< std::pair<_SortingPlacesIterator, _SortingPlacesIterator> > _SeqVector; _SeqVector __seqs(__sd->_M_num_threads); for (_ThreadIndex __s = 0; __s < __sd->_M_num_threads; ++__s) { __seqs[__s] = std::make_pair(__sd->_M_temporary[__s] + __sd->_M_pieces[__iam][__s]._M_begin, __sd->_M_temporary[__s] + __sd->_M_pieces[__iam][__s]._M_end); } __possibly_stable_multiway_merge< __stable, typename _SeqVector::iterator, _RAIter, _Compare, _DifferenceType>()(__seqs.begin(), __seqs.end(), __sd->_M_source + __offset, __comp, __length_am); # pragma omp barrier for (_DifferenceType __i = 0; __i < __length_local; ++__i) __sd->_M_temporary[__iam][__i].~_ValueType(); ::operator delete(__sd->_M_temporary[__iam]); } /** @brief PMWMS main call. * @param __begin Begin iterator of sequence. * @param __end End iterator of sequence. * @param __comp Comparator. * @param __num_threads Number of threads to use. / template<bool __stable, bool __exact, typename _RAIter, typename _Compare> void parallel_sort_mwms(_RAIter __begin, _RAIter __end, _Compare __comp, _ThreadIndex __num_threads) { _GLIBCXX_CALL(__end - __begin) typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; _DifferenceType __n = __end - __begin; if (__n <= 1) return; // at least one element per thread if (__num_threads > __n) __num_threads = static_cast<_ThreadIndex>(__n); // shared variables _PMWMSSortingData<_RAIter> __sd; _DifferenceType __starts; _DifferenceType __size; # pragma omp parallel num_threads(__num_threads) { __num_threads = omp_get_num_threads(); //no more threads than requested # pragma omp single { __sd._M_num_threads = __num_threads; __sd._M_source = __begin; __sd._M_temporary = new _ValueType[__num_threads]; if (!__exact) { __size = (_Settings::get().sort_mwms_oversampling __num_threads - 1) * __num_threads; __sd._M_samples = static_cast<_ValueType> (::operator new(__size sizeof(_ValueType))); } else __sd._M_samples = 0; __sd._M_offsets = new _DifferenceType[__num_threads - 1]; __sd._M_pieces = new std::vector<_Piece<_DifferenceType> >[__num_threads]; for (_ThreadIndex __s = 0; __s < __num_threads; ++__s) __sd._M_pieces[__s].resize(__num_threads); __starts = __sd._M_starts = new _DifferenceType[__num_threads + 1]; _DifferenceType __chunk_length = __n / __num_threads; _DifferenceType __split = __n % __num_threads; _DifferenceType __pos = 0; for (_ThreadIndex __i = 0; __i < __num_threads; ++__i) { __starts[__i] = __pos; __pos += ((__i < __split) ? (__chunk_length + 1) : __chunk_length); } __starts[__num_threads] = __pos; } //single // Now sort in parallel. parallel_sort_mwms_pu<__stable, __exact>(&__sd, __comp); } //parallel delete[] __starts; delete[] __sd._M_temporary; if (!__exact) { for (_DifferenceType __i = 0; __i < __size; ++__i) __sd._M_samples[__i].~_ValueType(); ::operator delete(__sd._M_samples); } delete[] __sd._M_offsets; delete[] __sd._M_pieces; } } //namespace __gnu_parallel #endif /* _GLIBCXX_PARALLEL_MULTIWAY_MERGESORT_H */	14.92 KB	2025-09-15 15:41
📄 numeric // -- C++ -- // Copyright (C) 2007-2021 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/numeric * * @brief Parallel STL function calls corresponding to stl_numeric.h. * The functions defined here mainly do case switches and * call the actual parallelized versions in other files. * Inlining policy: Functions that basically only contain one function call, * are declared inline. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler and Felix Putze. #ifndef _GLIBCXX_PARALLEL_NUMERIC_H #define _GLIBCXX_PARALLEL_NUMERIC_H 1 #include <numeric> #include <bits/stl_function.h> #include <parallel/numericfwd.h> #include <parallel/iterator.h> #include <parallel/for_each.h> #include <parallel/for_each_selectors.h> #include <parallel/partial_sum.h> namespace std _GLIBCXX_VISIBILITY(default) { namespace __parallel { // Sequential fallback. template<typename _IIter, typename _Tp> inline _Tp accumulate(_IIter __begin, _IIter __end, _Tp __init, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::accumulate(__begin, __end, __init); } template<typename _IIter, typename _Tp, typename _BinaryOperation> inline _Tp accumulate(_IIter __begin, _IIter __end, _Tp __init, _BinaryOperation __binary_op, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::accumulate(__begin, __end, __init, __binary_op); } // Sequential fallback for input iterator case. template<typename _IIter, typename _Tp, typename _IteratorTag> inline _Tp __accumulate_switch(_IIter __begin, _IIter __end, _Tp __init, _IteratorTag) { return accumulate(__begin, __end, __init, __gnu_parallel::sequential_tag()); } template<typename _IIter, typename _Tp, typename _BinaryOperation, typename _IteratorTag> inline _Tp __accumulate_switch(_IIter __begin, _IIter __end, _Tp __init, _BinaryOperation __binary_op, _IteratorTag) { return accumulate(__begin, __end, __init, __binary_op, __gnu_parallel::sequential_tag()); } // Parallel algorithm for random access iterators. template<typename __RAIter, typename _Tp, typename _BinaryOperation> _Tp __accumulate_switch(__RAIter __begin, __RAIter __end, _Tp __init, _BinaryOperation __binary_op, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().accumulate_minimal_n && __gnu_parallel::__is_parallel(__parallelism_tag))) { _Tp __res = __init; __gnu_parallel::__accumulate_selector<__RAIter> __my_selector; __gnu_parallel:: __for_each_template_random_access_ed(__begin, __end, __gnu_parallel::_Nothing(), __my_selector, __gnu_parallel:: __accumulate_binop_reduct <_BinaryOperation>(__binary_op), __res, __res, -1); return __res; } else return accumulate(__begin, __end, __init, __binary_op, __gnu_parallel::sequential_tag()); } // Public interface. template<typename _IIter, typename _Tp> inline _Tp accumulate(_IIter __begin, _IIter __end, _Tp __init, __gnu_parallel::_Parallelism __parallelism_tag) { typedef std::iterator_traits<_IIter> _IteratorTraits; typedef typename _IteratorTraits::value_type _ValueType; typedef typename _IteratorTraits::iterator_category _IteratorCategory; return __accumulate_switch(__begin, __end, __init, __gnu_parallel::_Plus<_Tp, _ValueType>(), _IteratorCategory(), __parallelism_tag); } template<typename _IIter, typename _Tp> inline _Tp accumulate(_IIter __begin, _IIter __end, _Tp __init) { typedef std::iterator_traits<_IIter> _IteratorTraits; typedef typename _IteratorTraits::value_type _ValueType; typedef typename _IteratorTraits::iterator_category _IteratorCategory; return __accumulate_switch(__begin, __end, __init, __gnu_parallel::_Plus<_Tp, _ValueType>(), _IteratorCategory()); } template<typename _IIter, typename _Tp, typename _BinaryOperation> inline _Tp accumulate(_IIter __begin, _IIter __end, _Tp __init, _BinaryOperation __binary_op, __gnu_parallel::_Parallelism __parallelism_tag) { typedef iterator_traits<_IIter> _IteratorTraits; typedef typename _IteratorTraits::iterator_category _IteratorCategory; return __accumulate_switch(__begin, __end, __init, __binary_op, _IteratorCategory(), __parallelism_tag); } template<typename _IIter, typename _Tp, typename _BinaryOperation> inline _Tp accumulate(_IIter __begin, _IIter __end, _Tp __init, _BinaryOperation __binary_op) { typedef iterator_traits<_IIter> _IteratorTraits; typedef typename _IteratorTraits::iterator_category _IteratorCategory; return __accumulate_switch(__begin, __end, __init, __binary_op, _IteratorCategory()); } // Sequential fallback. template<typename _IIter1, typename _IIter2, typename _Tp> inline _Tp inner_product(_IIter1 __first1, _IIter1 __last1, _IIter2 __first2, _Tp __init, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::inner_product( __first1, __last1, __first2, __init); } template<typename _IIter1, typename _IIter2, typename _Tp, typename _BinaryFunction1, typename _BinaryFunction2> inline _Tp inner_product(_IIter1 __first1, _IIter1 __last1, _IIter2 __first2, _Tp __init, _BinaryFunction1 __binary_op1, _BinaryFunction2 __binary_op2, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::inner_product(__first1, __last1, __first2, __init, __binary_op1, __binary_op2); } // Parallel algorithm for random access iterators. template<typename _RAIter1, typename _RAIter2, typename _Tp, typename _BinaryFunction1, typename _BinaryFunction2> _Tp __inner_product_switch(_RAIter1 __first1, _RAIter1 __last1, _RAIter2 __first2, _Tp __init, _BinaryFunction1 __binary_op1, _BinaryFunction2 __binary_op2, random_access_iterator_tag, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism_tag) { if (_GLIBCXX_PARALLEL_CONDITION((__last1 - __first1) >= __gnu_parallel::_Settings::get(). accumulate_minimal_n && __gnu_parallel:: __is_parallel(__parallelism_tag))) { _Tp __res = __init; __gnu_parallel:: __inner_product_selector<_RAIter1, _RAIter2, _Tp> __my_selector(__first1, __first2); __gnu_parallel:: __for_each_template_random_access_ed( __first1, __last1, __binary_op2, __my_selector, __binary_op1, __res, __res, -1); return __res; } else return inner_product(__first1, __last1, __first2, __init, __gnu_parallel::sequential_tag()); } // No parallelism for input iterators. template<typename _IIter1, typename _IIter2, typename _Tp, typename _BinaryFunction1, typename _BinaryFunction2, typename _IteratorTag1, typename _IteratorTag2> inline _Tp __inner_product_switch(_IIter1 __first1, _IIter1 __last1, _IIter2 __first2, _Tp __init, _BinaryFunction1 __binary_op1, _BinaryFunction2 __binary_op2, _IteratorTag1, _IteratorTag2) { return inner_product(__first1, __last1, __first2, __init, __binary_op1, __binary_op2, __gnu_parallel::sequential_tag()); } template<typename _IIter1, typename _IIter2, typename _Tp, typename _BinaryFunction1, typename _BinaryFunction2> inline _Tp inner_product(_IIter1 __first1, _IIter1 __last1, _IIter2 __first2, _Tp __init, _BinaryFunction1 __binary_op1, _BinaryFunction2 __binary_op2, __gnu_parallel::_Parallelism __parallelism_tag) { typedef iterator_traits<_IIter1> _TraitsType1; typedef typename _TraitsType1::iterator_category _IteratorCategory1; typedef iterator_traits<_IIter2> _TraitsType2; typedef typename _TraitsType2::iterator_category _IteratorCategory2; return __inner_product_switch(__first1, __last1, __first2, __init, __binary_op1, __binary_op2, _IteratorCategory1(), _IteratorCategory2(), __parallelism_tag); } template<typename _IIter1, typename _IIter2, typename _Tp, typename _BinaryFunction1, typename _BinaryFunction2> inline _Tp inner_product(_IIter1 __first1, _IIter1 __last1, _IIter2 __first2, _Tp __init, _BinaryFunction1 __binary_op1, _BinaryFunction2 __binary_op2) { typedef iterator_traits<_IIter1> _TraitsType1; typedef typename _TraitsType1::iterator_category _IteratorCategory1; typedef iterator_traits<_IIter2> _TraitsType2; typedef typename _TraitsType2::iterator_category _IteratorCategory2; return __inner_product_switch(__first1, __last1, __first2, __init, __binary_op1, __binary_op2, _IteratorCategory1(), _IteratorCategory2()); } template<typename _IIter1, typename _IIter2, typename _Tp> inline _Tp inner_product(_IIter1 __first1, _IIter1 __last1, _IIter2 __first2, _Tp __init, __gnu_parallel::_Parallelism __parallelism_tag) { typedef iterator_traits<_IIter1> _TraitsType1; typedef typename _TraitsType1::value_type _ValueType1; typedef iterator_traits<_IIter2> _TraitsType2; typedef typename _TraitsType2::value_type _ValueType2; typedef typename __gnu_parallel::_Multiplies<_ValueType1, _ValueType2>::result_type _MultipliesResultType; return __gnu_parallel::inner_product(__first1, __last1, __first2, __init, __gnu_parallel::_Plus<_Tp, _MultipliesResultType>(), __gnu_parallel:: _Multiplies<_ValueType1, _ValueType2>(), __parallelism_tag); } template<typename _IIter1, typename _IIter2, typename _Tp> inline _Tp inner_product(_IIter1 __first1, _IIter1 __last1, _IIter2 __first2, _Tp __init) { typedef iterator_traits<_IIter1> _TraitsType1; typedef typename _TraitsType1::value_type _ValueType1; typedef iterator_traits<_IIter2> _TraitsType2; typedef typename _TraitsType2::value_type _ValueType2; typedef typename __gnu_parallel::_Multiplies<_ValueType1, _ValueType2>::result_type _MultipliesResultType; return __gnu_parallel::inner_product(__first1, __last1, __first2, __init, __gnu_parallel::_Plus<_Tp, _MultipliesResultType>(), __gnu_parallel:: _Multiplies<_ValueType1, _ValueType2>()); } // Sequential fallback. template<typename _IIter, typename _OutputIterator> inline _OutputIterator partial_sum(_IIter __begin, _IIter __end, _OutputIterator __result, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::partial_sum(__begin, __end, __result); } // Sequential fallback. template<typename _IIter, typename _OutputIterator, typename _BinaryOperation> inline _OutputIterator partial_sum(_IIter __begin, _IIter __end, _OutputIterator __result, _BinaryOperation __bin_op, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::partial_sum(__begin, __end, __result, __bin_op); } // Sequential fallback for input iterator case. template<typename _IIter, typename _OutputIterator, typename _BinaryOperation, typename _IteratorTag1, typename _IteratorTag2> inline _OutputIterator __partial_sum_switch(_IIter __begin, _IIter __end, _OutputIterator __result, _BinaryOperation __bin_op, _IteratorTag1, _IteratorTag2) { return _GLIBCXX_STD_A::partial_sum(__begin, __end, __result, __bin_op); } // Parallel algorithm for random access iterators. template<typename _IIter, typename _OutputIterator, typename _BinaryOperation> _OutputIterator __partial_sum_switch(_IIter __begin, _IIter __end, _OutputIterator __result, _BinaryOperation __bin_op, random_access_iterator_tag, random_access_iterator_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().partial_sum_minimal_n)) return __gnu_parallel::__parallel_partial_sum(__begin, __end, __result, __bin_op); else return partial_sum(__begin, __end, __result, __bin_op, __gnu_parallel::sequential_tag()); } // Public interface. template<typename _IIter, typename _OutputIterator> inline _OutputIterator partial_sum(_IIter __begin, _IIter __end, _OutputIterator __result) { typedef typename iterator_traits<_IIter>::value_type _ValueType; return __gnu_parallel::partial_sum(__begin, __end, __result, std::plus<_ValueType>()); } // Public interface template<typename _IIter, typename _OutputIterator, typename _BinaryOperation> inline _OutputIterator partial_sum(_IIter __begin, _IIter __end, _OutputIterator __result, _BinaryOperation __binary_op) { typedef iterator_traits<_IIter> _ITraitsType; typedef typename _ITraitsType::iterator_category _IIteratorCategory; typedef iterator_traits<_OutputIterator> _OTraitsType; typedef typename _OTraitsType::iterator_category _OIterCategory; return __partial_sum_switch(__begin, __end, __result, __binary_op, _IIteratorCategory(), _OIterCategory()); } // Sequential fallback. template<typename _IIter, typename _OutputIterator> inline _OutputIterator adjacent_difference(_IIter __begin, _IIter __end, _OutputIterator __result, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::adjacent_difference(__begin, __end, __result); } // Sequential fallback. template<typename _IIter, typename _OutputIterator, typename _BinaryOperation> inline _OutputIterator adjacent_difference(_IIter __begin, _IIter __end, _OutputIterator __result, _BinaryOperation __bin_op, __gnu_parallel::sequential_tag) { return _GLIBCXX_STD_A::adjacent_difference(__begin, __end, __result, __bin_op); } // Sequential fallback for input iterator case. template<typename _IIter, typename _OutputIterator, typename _BinaryOperation, typename _IteratorTag1, typename _IteratorTag2> inline _OutputIterator __adjacent_difference_switch(_IIter __begin, _IIter __end, _OutputIterator __result, _BinaryOperation __bin_op, _IteratorTag1, _IteratorTag2) { return adjacent_difference(__begin, __end, __result, __bin_op, __gnu_parallel::sequential_tag()); } // Parallel algorithm for random access iterators. template<typename _IIter, typename _OutputIterator, typename _BinaryOperation> _OutputIterator __adjacent_difference_switch(_IIter __begin, _IIter __end, _OutputIterator __result, _BinaryOperation __bin_op, random_access_iterator_tag, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism_tag) { if (_GLIBCXX_PARALLEL_CONDITION( static_cast<__gnu_parallel::_SequenceIndex>(__end - __begin) >= __gnu_parallel::_Settings::get().adjacent_difference_minimal_n && __gnu_parallel::__is_parallel(__parallelism_tag))) { bool __dummy = true; typedef __gnu_parallel::_IteratorPair<_IIter, _OutputIterator, random_access_iterator_tag> _ItTrip; __result = __begin; _ItTrip __begin_pair(__begin + 1, __result + 1), __end_pair(__end, __result + (__end - __begin)); __gnu_parallel::__adjacent_difference_selector<_ItTrip> __functionality; __gnu_parallel:: __for_each_template_random_access_ed( __begin_pair, __end_pair, __bin_op, __functionality, __gnu_parallel::_DummyReduct(), __dummy, __dummy, -1); return __functionality._M_finish_iterator; } else return adjacent_difference(__begin, __end, __result, __bin_op, __gnu_parallel::sequential_tag()); } // Public interface. template<typename _IIter, typename _OutputIterator> inline _OutputIterator adjacent_difference(_IIter __begin, _IIter __end, _OutputIterator __result, __gnu_parallel::_Parallelism __parallelism_tag) { typedef iterator_traits<_IIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; return adjacent_difference(__begin, __end, __result, std::minus<_ValueType>(), __parallelism_tag); } template<typename _IIter, typename _OutputIterator> inline _OutputIterator adjacent_difference(_IIter __begin, _IIter __end, _OutputIterator __result) { typedef iterator_traits<_IIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; return adjacent_difference(__begin, __end, __result, std::minus<_ValueType>()); } template<typename _IIter, typename _OutputIterator, typename _BinaryOperation> inline _OutputIterator adjacent_difference(_IIter __begin, _IIter __end, _OutputIterator __result, _BinaryOperation __binary_op, __gnu_parallel::_Parallelism __parallelism_tag) { typedef iterator_traits<_IIter> _ITraitsType; typedef typename _ITraitsType::iterator_category _IIteratorCategory; typedef iterator_traits<_OutputIterator> _OTraitsType; typedef typename _OTraitsType::iterator_category _OIterCategory; return __adjacent_difference_switch(__begin, __end, __result, __binary_op, _IIteratorCategory(), _OIterCategory(), __parallelism_tag); } template<typename _IIter, typename _OutputIterator, typename _BinaryOperation> inline _OutputIterator adjacent_difference(_IIter __begin, _IIter __end, _OutputIterator __result, _BinaryOperation __binary_op) { typedef iterator_traits<_IIter> _ITraitsType; typedef typename _ITraitsType::iterator_category _IIteratorCategory; typedef iterator_traits<_OutputIterator> _OTraitsType; typedef typename _OTraitsType::iterator_category _OIterCategory; return __adjacent_difference_switch(__begin, __end, __result, __binary_op, _IIteratorCategory(), _OIterCategory()); } } // end namespace } // end namespace #endif / _GLIBCXX_NUMERIC_H */	20.23 KB	2025-09-15 15:41
📄 numericfwd.h // <parallel/numeric> Forward declarations -- C++ -- // Copyright (C) 2007-2021 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/numericfwd.h * This file is a GNU parallel extension to the Standard C++ Library. / #ifndef _GLIBCXX_PARALLEL_NUMERICFWD_H #define _GLIBCXX_PARALLEL_NUMERICFWD_H 1 #pragma GCC system_header #include <parallel/tags.h> #include <parallel/settings.h> namespace std _GLIBCXX_VISIBILITY(default) { namespace __parallel { template<typename _IIter, typename _Tp> _Tp accumulate(_IIter, _IIter, _Tp); template<typename _IIter, typename _Tp> _Tp accumulate(_IIter, _IIter, _Tp, __gnu_parallel::sequential_tag); template<typename _IIter, typename _Tp> _Tp accumulate(_IIter, _IIter, _Tp, __gnu_parallel::_Parallelism); template<typename _IIter, typename _Tp, typename _Tag> _Tp __accumulate_switch(_IIter, _IIter, _Tp, _Tag); template<typename _IIter, typename _Tp, typename _BinaryOper> _Tp accumulate(_IIter, _IIter, _Tp, _BinaryOper); template<typename _IIter, typename _Tp, typename _BinaryOper> _Tp accumulate(_IIter, _IIter, _Tp, _BinaryOper, __gnu_parallel::sequential_tag); template<typename _IIter, typename _Tp, typename _BinaryOper> _Tp accumulate(_IIter, _IIter, _Tp, _BinaryOper, __gnu_parallel::_Parallelism); template<typename _IIter, typename _Tp, typename _BinaryOper, typename _Tag> _Tp __accumulate_switch(_IIter, _IIter, _Tp, _BinaryOper, _Tag); template<typename _RAIter, typename _Tp, typename _BinaryOper> _Tp __accumulate_switch(_RAIter, _RAIter, _Tp, _BinaryOper, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism = __gnu_parallel::parallel_unbalanced); template<typename _IIter, typename _OIter> _OIter adjacent_difference(_IIter, _IIter, _OIter); template<typename _IIter, typename _OIter, typename _BinaryOper> _OIter adjacent_difference(_IIter, _IIter, _OIter, _BinaryOper); template<typename _IIter, typename _OIter> _OIter adjacent_difference(_IIter, _IIter, _OIter, __gnu_parallel::sequential_tag); template<typename _IIter, typename _OIter, typename _BinaryOper> _OIter adjacent_difference(_IIter, _IIter, _OIter, _BinaryOper, __gnu_parallel::sequential_tag); template<typename _IIter, typename _OIter> _OIter adjacent_difference(_IIter, _IIter, _OIter, __gnu_parallel::_Parallelism); template<typename _IIter, typename _OIter, typename _BinaryOper> _OIter adjacent_difference(_IIter, _IIter, _OIter, _BinaryOper, __gnu_parallel::_Parallelism); template<typename _IIter, typename _OIter, typename _BinaryOper, typename _Tag1, typename _Tag2> _OIter __adjacent_difference_switch(_IIter, _IIter, _OIter, _BinaryOper, _Tag1, _Tag2); template<typename _IIter, typename _OIter, typename _BinaryOper> _OIter __adjacent_difference_switch(_IIter, _IIter, _OIter, _BinaryOper, random_access_iterator_tag, random_access_iterator_tag, __gnu_parallel::_Parallelism __parallelism = __gnu_parallel::parallel_unbalanced); template<typename _IIter1, typename _IIter2, typename _Tp> _Tp inner_product(_IIter1, _IIter1, _IIter2, _Tp); template<typename _IIter1, typename _IIter2, typename _Tp> _Tp inner_product(_IIter1, _IIter1, _IIter2, _Tp, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2, typename _Tp> _Tp inner_product(_IIter1, _IIter1, _IIter2, _Tp, __gnu_parallel::_Parallelism); template<typename _IIter1, typename _IIter2, typename _Tp, typename _BinaryFunction1, typename _BinaryFunction2> _Tp inner_product(_IIter1, _IIter1, _IIter2, _Tp, _BinaryFunction1, _BinaryFunction2); template<typename _IIter1, typename _IIter2, typename _Tp, typename _BinaryFunction1, typename _BinaryFunction2> _Tp inner_product(_IIter1, _IIter1, _IIter2, _Tp, _BinaryFunction1, _BinaryFunction2, __gnu_parallel::sequential_tag); template<typename _IIter1, typename _IIter2, typename _Tp, typename _BinaryFunction1, typename _BinaryFunction2> _Tp inner_product(_IIter1, _IIter1, _IIter2, _Tp, _BinaryFunction1, _BinaryFunction2, __gnu_parallel::_Parallelism); template<typename _RAIter1, typename _RAIter2, typename _Tp, typename _BinaryFunction1, typename _BinaryFunction2> _Tp __inner_product_switch(_RAIter1, _RAIter1, _RAIter2, _Tp, _BinaryFunction1, _BinaryFunction2, random_access_iterator_tag, random_access_iterator_tag, __gnu_parallel::_Parallelism = __gnu_parallel::parallel_unbalanced); template<typename _IIter1, typename _IIter2, typename _Tp, typename _BinaryFunction1, typename _BinaryFunction2, typename _Tag1, typename _Tag2> _Tp __inner_product_switch(_IIter1, _IIter1, _IIter2, _Tp, _BinaryFunction1, _BinaryFunction2, _Tag1, _Tag2); template<typename _IIter, typename _OIter> _OIter partial_sum(_IIter, _IIter, _OIter, __gnu_parallel::sequential_tag); template<typename _IIter, typename _OIter, typename _BinaryOper> _OIter partial_sum(_IIter, _IIter, _OIter, _BinaryOper, __gnu_parallel::sequential_tag); template<typename _IIter, typename _OIter> _OIter partial_sum(_IIter, _IIter, _OIter __result); template<typename _IIter, typename _OIter, typename _BinaryOper> _OIter partial_sum(_IIter, _IIter, _OIter, _BinaryOper); template<typename _IIter, typename _OIter, typename _BinaryOper, typename _Tag1, typename _Tag2> _OIter __partial_sum_switch(_IIter, _IIter, _OIter, _BinaryOper, _Tag1, _Tag2); template<typename _IIter, typename _OIter, typename _BinaryOper> _OIter __partial_sum_switch(_IIter, _IIter, _OIter, _BinaryOper, random_access_iterator_tag, random_access_iterator_tag); } // end namespace } // end namespace #endif / _GLIBCXX_PARALLEL_NUMERICFWD_H */	7.33 KB	2025-09-15 15:41
📄 omp_loop.h // -- C++ -- // Copyright (C) 2007-2021 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/omp_loop.h * @brief Parallelization of embarrassingly parallel execution by * means of an OpenMP for loop. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Felix Putze. #ifndef _GLIBCXX_PARALLEL_OMP_LOOP_H #define _GLIBCXX_PARALLEL_OMP_LOOP_H 1 #include <omp.h> #include <parallel/settings.h> #include <parallel/basic_iterator.h> #include <parallel/base.h> namespace __gnu_parallel { /* @brief Embarrassingly parallel algorithm for random access * iterators, using an OpenMP for loop. * * @param __begin Begin iterator of element sequence. * @param __end End iterator of element sequence. * @param __o User-supplied functor (comparator, predicate, adding * functor, etc.). * @param __f Functor to @a process an element with __op (depends on * desired functionality, e. g. for std::for_each(), ...). * @param __r Functor to @a add a single __result to the already * processed elements (depends on functionality). * @param __base Base value for reduction. * @param __output Pointer to position where final result is written to * @param __bound Maximum number of elements processed (e. g. for * std::count_n()). * @return User-supplied functor (that may contain a part of the result). / template<typename _RAIter, typename _Op, typename _Fu, typename _Red, typename _Result> _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) { typedef typename std::iterator_traits<_RAIter>::difference_type _DifferenceType; _DifferenceType __length = __end - __begin; _ThreadIndex __num_threads = __gnu_parallel::min<_DifferenceType> (__get_max_threads(), __length); _Result __thread_results; # pragma omp parallel num_threads(__num_threads) { # pragma omp single { __num_threads = omp_get_num_threads(); __thread_results = new _Result[__num_threads]; for (_ThreadIndex __i = 0; __i < __num_threads; ++__i) __thread_results[__i] = _Result(); } _ThreadIndex __iam = omp_get_thread_num(); #pragma omp for schedule(dynamic, _Settings::get().workstealing_chunk_size) for (_DifferenceType __pos = 0; __pos < __length; ++__pos) __thread_results[__iam] = __r(__thread_results[__iam], __f(__o, __begin+__pos)); } //parallel for (_ThreadIndex __i = 0; __i < __num_threads; ++__i) __output = __r(__output, __thread_results[__i]); delete [] __thread_results; // Points to last element processed (needed as return value for // some algorithms like transform). __f._M_finish_iterator = __begin + __length; return __o; } } // end namespace #endif /* _GLIBCXX_PARALLEL_OMP_LOOP_H */	3.94 KB	2025-09-15 15:41
📄 omp_loop_static.h // -- C++ -- // Copyright (C) 2007-2021 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/omp_loop_static.h * @brief Parallelization of embarrassingly parallel execution by * means of an OpenMP for loop with static scheduling. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Felix Putze. #ifndef _GLIBCXX_PARALLEL_OMP_LOOP_STATIC_H #define _GLIBCXX_PARALLEL_OMP_LOOP_STATIC_H 1 #include <omp.h> #include <parallel/settings.h> #include <parallel/basic_iterator.h> namespace __gnu_parallel { /* @brief Embarrassingly parallel algorithm for random access * iterators, using an OpenMP for loop with static scheduling. * * @param __begin Begin iterator of element sequence. * @param __end End iterator of element sequence. * @param __o User-supplied functor (comparator, predicate, adding * functor, ...). * @param __f Functor to @a process an element with __op (depends on * desired functionality, e. g. for std::for_each(), ...). * @param __r Functor to @a add a single __result to the already processed * __elements (depends on functionality). * @param __base Base value for reduction. * @param __output Pointer to position where final result is written to * @param __bound Maximum number of elements processed (e. g. for * std::count_n()). * @return User-supplied functor (that may contain a part of the result). / template<typename _RAIter, typename _Op, typename _Fu, typename _Red, typename _Result> _Op __for_each_template_random_access_omp_loop_static(_RAIter __begin, _RAIter __end, _Op __o, _Fu& __f, _Red __r, _Result __base, _Result& __output, typename std::iterator_traits<_RAIter>::difference_type __bound) { typedef typename std::iterator_traits<_RAIter>::difference_type _DifferenceType; _DifferenceType __length = __end - __begin; _ThreadIndex __num_threads = std::min<_DifferenceType> (__get_max_threads(), __length); _Result __thread_results; # pragma omp parallel num_threads(__num_threads) { # pragma omp single { __num_threads = omp_get_num_threads(); __thread_results = new _Result[__num_threads]; for (_ThreadIndex __i = 0; __i < __num_threads; ++__i) __thread_results[__i] = _Result(); } _ThreadIndex __iam = omp_get_thread_num(); #pragma omp for schedule(static, _Settings::get().workstealing_chunk_size) for (_DifferenceType __pos = 0; __pos < __length; ++__pos) __thread_results[__iam] = __r(__thread_results[__iam], __f(__o, __begin+__pos)); } //parallel for (_ThreadIndex __i = 0; __i < __num_threads; ++__i) __output = __r(__output, __thread_results[__i]); delete [] __thread_results; // Points to last element processed (needed as return value for // some algorithms like transform). __f.finish_iterator = __begin + __length; return __o; } } // end namespace #endif /* _GLIBCXX_PARALLEL_OMP_LOOP_STATIC_H */	4.01 KB	2025-09-15 15:41
📄 par_loop.h // -- C++ -- // Copyright (C) 2007-2021 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/par_loop.h * @brief Parallelization of embarrassingly parallel execution by * means of equal splitting. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Felix Putze. #ifndef _GLIBCXX_PARALLEL_PAR_LOOP_H #define _GLIBCXX_PARALLEL_PAR_LOOP_H 1 #include <omp.h> #include <parallel/settings.h> #include <parallel/base.h> #include <parallel/equally_split.h> namespace __gnu_parallel { /* @brief Embarrassingly parallel algorithm for random access * iterators, using hand-crafted parallelization by equal splitting * the work. * * @param __begin Begin iterator of element sequence. * @param __end End iterator of element sequence. * @param __o User-supplied functor (comparator, predicate, adding * functor, ...) * @param __f Functor to "process" an element with __op (depends on * desired functionality, e. g. for std::for_each(), ...). * @param __r Functor to "add" a single __result to the already * processed elements (depends on functionality). * @param __base Base value for reduction. * @param __output Pointer to position where final result is written to * @param __bound Maximum number of elements processed (e. g. for * std::count_n()). * @return User-supplied functor (that may contain a part of the result). / template<typename _RAIter, typename _Op, typename _Fu, typename _Red, typename _Result> _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) { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::difference_type _DifferenceType; const _DifferenceType __length = __end - __begin; _Result __thread_results; bool* __constructed; _ThreadIndex __num_threads = __gnu_parallel::min<_DifferenceType> (__get_max_threads(), __length); # pragma omp parallel num_threads(__num_threads) { # pragma omp single { __num_threads = omp_get_num_threads(); __thread_results = static_cast<_Result> (::operator new(__num_threads sizeof(_Result))); __constructed = new bool[__num_threads]; } _ThreadIndex __iam = omp_get_thread_num(); // Neutral element. _Result* __reduct; _DifferenceType __start = __equally_split_point(__length, __num_threads, __iam), __stop = __equally_split_point(__length, __num_threads, __iam + 1); if (__start < __stop) { __reduct = new _Result(__f(__o, __begin + __start)); ++__start; __constructed[__iam] = true; } else __constructed[__iam] = false; for (; __start < __stop; ++__start) __reduct = __r(__reduct, __f(__o, __begin + __start)); if (__constructed[__iam]) { ::new(&__thread_results[__iam]) _Result(__reduct); delete __reduct; } } //parallel for (_ThreadIndex __i = 0; __i < __num_threads; ++__i) if (__constructed[__i]) { __output = __r(__output, __thread_results[__i]); __thread_results[__i].~_Result(); } // Points to last element processed (needed as return value for // some algorithms like transform). __f._M_finish_iterator = __begin + __length; ::operator delete(__thread_results); delete[] __constructed; return __o; } } // end namespace #endif / _GLIBCXX_PARALLEL_PAR_LOOP_H */	4.45 KB	2025-09-15 15:41
📄 parallel.h // -- C++ -- // Copyright (C) 2007-2021 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/parallel.h * @brief End-user include file. Provides advanced settings and * tuning options. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Felix Putze and Johannes Singler. #ifndef _GLIBCXX_PARALLEL_PARALLEL_H #define _GLIBCXX_PARALLEL_PARALLEL_H 1 #include <parallel/features.h> #include <parallel/compiletime_settings.h> #include <parallel/types.h> #include <parallel/tags.h> #include <parallel/settings.h> #endif / _GLIBCXX_PARALLEL_PARALLEL_H */	1.54 KB	2025-09-15 15:41
📄 partial_sum.h // -- C++ -- // Copyright (C) 2007-2021 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/partial_sum.h * @brief Parallel implementation of std::partial_sum(), i.e. prefix * sums. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_PARTIAL_SUM_H #define _GLIBCXX_PARALLEL_PARTIAL_SUM_H 1 #include <omp.h> #include <new> #include <bits/stl_algobase.h> #include <parallel/parallel.h> #include <parallel/numericfwd.h> namespace __gnu_parallel { // Problem: there is no 0-element given. /* @brief Base case prefix sum routine. * @param __begin Begin iterator of input sequence. * @param __end End iterator of input sequence. * @param __result Begin iterator of output sequence. * @param __bin_op Associative binary function. * @param __value Start value. Must be passed since the neutral * element is unknown in general. * @return End iterator of output sequence. / template<typename _IIter, typename _OutputIterator, typename _BinaryOperation> _OutputIterator __parallel_partial_sum_basecase(_IIter __begin, _IIter __end, _OutputIterator __result, _BinaryOperation __bin_op, typename std::iterator_traits <_IIter>::value_type __value) { if (__begin == __end) return __result; while (__begin != __end) { __value = __bin_op(__value, __begin); __result = __value; ++__result; ++__begin; } return __result; } /* @brief Parallel partial sum implementation, two-phase approach, no recursion. * @param __begin Begin iterator of input sequence. * @param __end End iterator of input sequence. * @param __result Begin iterator of output sequence. * @param __bin_op Associative binary function. * @param __n Length of sequence. * @return End iterator of output sequence. / template<typename _IIter, typename _OutputIterator, typename _BinaryOperation> _OutputIterator __parallel_partial_sum_linear(_IIter __begin, _IIter __end, _OutputIterator __result, _BinaryOperation __bin_op, typename std::iterator_traits<_IIter>::difference_type __n) { typedef std::iterator_traits<_IIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; if (__begin == __end) return __result; _ThreadIndex __num_threads = std::min<_DifferenceType>(__get_max_threads(), __n - 1); if (__num_threads < 2) { __result = __begin; return __parallel_partial_sum_basecase(__begin + 1, __end, __result + 1, __bin_op, __begin); } _DifferenceType* __borders; _ValueType* __sums; const _Settings& __s = _Settings::get(); # pragma omp parallel num_threads(__num_threads) { # pragma omp single { __num_threads = omp_get_num_threads(); __borders = new _DifferenceType[__num_threads + 2]; if (__s.partial_sum_dilation == 1.0f) __equally_split(__n, __num_threads + 1, __borders); else { _DifferenceType __first_part_length = std::max<_DifferenceType>(1, __n / (1.0f + __s.partial_sum_dilation * __num_threads)); _DifferenceType __chunk_length = (__n - __first_part_length) / __num_threads; _DifferenceType __borderstart = __n - __num_threads * __chunk_length; __borders[0] = 0; for (_ThreadIndex __i = 1; __i < (__num_threads + 1); ++__i) { __borders[__i] = __borderstart; __borderstart += __chunk_length; } __borders[__num_threads + 1] = __n; } __sums = static_cast<_ValueType>(::operator new(sizeof(_ValueType) __num_threads)); _OutputIterator __target_end; } //single _ThreadIndex __iam = omp_get_thread_num(); if (__iam == 0) { __result = __begin; __parallel_partial_sum_basecase(__begin + 1, __begin + __borders[1], __result + 1, __bin_op, __begin); ::new(&(__sums[__iam])) _ValueType((__result + __borders[1] - 1)); } else { ::new(&(__sums[__iam])) _ValueType(__gnu_parallel::accumulate( __begin + __borders[__iam] + 1, __begin + __borders[__iam + 1], (__begin + __borders[__iam]), __bin_op, __gnu_parallel::sequential_tag())); } # pragma omp barrier # pragma omp single __parallel_partial_sum_basecase(__sums + 1, __sums + __num_threads, __sums + 1, __bin_op, __sums[0]); # pragma omp barrier // Still same team. __parallel_partial_sum_basecase(__begin + __borders[__iam + 1], __begin + __borders[__iam + 2], __result + __borders[__iam + 1], __bin_op, __sums[__iam]); } //parallel for (_ThreadIndex __i = 0; __i < __num_threads; ++__i) __sums[__i].~_ValueType(); ::operator delete(__sums); delete[] __borders; return __result + __n; } /* @brief Parallel partial sum front-__end. * @param __begin Begin iterator of input sequence. * @param __end End iterator of input sequence. * @param __result Begin iterator of output sequence. * @param __bin_op Associative binary function. * @return End iterator of output sequence. / template<typename _IIter, typename _OutputIterator, typename _BinaryOperation> _OutputIterator __parallel_partial_sum(_IIter __begin, _IIter __end, _OutputIterator __result, _BinaryOperation __bin_op) { _GLIBCXX_CALL(__begin - __end) typedef std::iterator_traits<_IIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; _DifferenceType __n = __end - __begin; switch (_Settings::get().partial_sum_algorithm) { case LINEAR: // Need an initial offset. return __parallel_partial_sum_linear(__begin, __end, __result, __bin_op, __n); default: // Partial_sum algorithm not implemented. _GLIBCXX_PARALLEL_ASSERT(0); return __result + __n; } } } #endif / _GLIBCXX_PARALLEL_PARTIAL_SUM_H */	7.3 KB	2025-09-15 15:41
📄 partition.h // -- C++ -- // Copyright (C) 2007-2021 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/partition.h * @brief Parallel implementation of std::partition(), * std::nth_element(), and std::partial_sort(). * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler and Felix Putze. #ifndef _GLIBCXX_PARALLEL_PARTITION_H #define _GLIBCXX_PARALLEL_PARTITION_H 1 #include <parallel/basic_iterator.h> #include <parallel/sort.h> #include <parallel/random_number.h> #include <bits/stl_algo.h> #include <parallel/parallel.h> /* @brief Decide whether to declare certain variables volatile. / #define _GLIBCXX_VOLATILE volatile namespace __gnu_parallel { /* @brief Parallel implementation of std::partition. * @param __begin Begin iterator of input sequence to split. * @param __end End iterator of input sequence to split. * @param __pred Partition predicate, possibly including some kind * of pivot. * @param __num_threads Maximum number of threads to use for this task. * @return Number of elements not fulfilling the predicate. / template<typename _RAIter, typename _Predicate> typename std::iterator_traits<_RAIter>::difference_type __parallel_partition(_RAIter __begin, _RAIter __end, _Predicate __pred, _ThreadIndex __num_threads) { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; _DifferenceType __n = __end - __begin; _GLIBCXX_CALL(__n) const _Settings& __s = _Settings::get(); // shared _GLIBCXX_VOLATILE _DifferenceType __left = 0, __right = __n - 1, __dist = __n, __leftover_left, __leftover_right, __leftnew, __rightnew; // just 0 or 1, but int to allow atomic operations int __reserved_left = 0, * __reserved_right = 0; _DifferenceType __chunk_size = __s.partition_chunk_size; //at least two chunks per thread if (__dist >= 2 * __num_threads * __chunk_size) # pragma omp parallel num_threads(__num_threads) { # pragma omp single { __num_threads = omp_get_num_threads(); __reserved_left = new int[__num_threads]; __reserved_right = new int[__num_threads]; if (__s.partition_chunk_share > 0.0) __chunk_size = std::max<_DifferenceType> (__s.partition_chunk_size, (double)__n * __s.partition_chunk_share / (double)__num_threads); else __chunk_size = __s.partition_chunk_size; } while (__dist >= 2 * __num_threads * __chunk_size) { # pragma omp single { _DifferenceType __num_chunks = __dist / __chunk_size; for (_ThreadIndex __r = 0; __r < __num_threads; ++__r) { __reserved_left [__r] = 0; // false __reserved_right[__r] = 0; // false } __leftover_left = 0; __leftover_right = 0; } //implicit barrier // Private. _DifferenceType __thread_left, __thread_left_border, __thread_right, __thread_right_border; __thread_left = __left + 1; // Just to satisfy the condition below. __thread_left_border = __thread_left - 1; __thread_right = __n - 1; // Just to satisfy the condition below. __thread_right_border = __thread_right + 1; bool __iam_finished = false; while (!__iam_finished) { if (__thread_left > __thread_left_border) { _DifferenceType __former_dist = __fetch_and_add(&__dist, -__chunk_size); if (__former_dist < __chunk_size) { __fetch_and_add(&__dist, __chunk_size); __iam_finished = true; break; } else { __thread_left = __fetch_and_add(&__left, __chunk_size); __thread_left_border = __thread_left + (__chunk_size - 1); } } if (__thread_right < __thread_right_border) { _DifferenceType __former_dist = __fetch_and_add(&__dist, -__chunk_size); if (__former_dist < __chunk_size) { __fetch_and_add(&__dist, __chunk_size); __iam_finished = true; break; } else { __thread_right = __fetch_and_add(&__right, -__chunk_size); __thread_right_border = __thread_right - (__chunk_size - 1); } } // Swap as usual. while (__thread_left < __thread_right) { while (__pred(__begin[__thread_left]) && __thread_left <= __thread_left_border) ++__thread_left; while (!__pred(__begin[__thread_right]) && __thread_right >= __thread_right_border) --__thread_right; if (__thread_left > __thread_left_border \|\| __thread_right < __thread_right_border) // Fetch new chunk(__s). break; std::iter_swap(__begin + __thread_left, __begin + __thread_right); ++__thread_left; --__thread_right; } } // Now swap the leftover chunks to the right places. if (__thread_left <= __thread_left_border) # pragma omp atomic ++__leftover_left; if (__thread_right >= __thread_right_border) # pragma omp atomic ++__leftover_right; # pragma omp barrier _DifferenceType __leftold = __left, __leftnew = __left - __leftover_left * __chunk_size, __rightold = __right, __rightnew = __right + __leftover_right * __chunk_size; // <=> __thread_left_border + (__chunk_size - 1) >= __leftnew if (__thread_left <= __thread_left_border && __thread_left_border >= __leftnew) { // Chunk already in place, reserve spot. __reserved_left[(__left - (__thread_left_border + 1)) / __chunk_size] = 1; } // <=> __thread_right_border - (__chunk_size - 1) <= __rightnew if (__thread_right >= __thread_right_border && __thread_right_border <= __rightnew) { // Chunk already in place, reserve spot. __reserved_right[((__thread_right_border - 1) - __right) / __chunk_size] = 1; } # pragma omp barrier if (__thread_left <= __thread_left_border && __thread_left_border < __leftnew) { // Find spot and swap. _DifferenceType __swapstart = -1; for (int __r = 0; __r < __leftover_left; ++__r) if (__reserved_left[__r] == 0 && __compare_and_swap(&(__reserved_left[__r]), 0, 1)) { __swapstart = __leftold - (__r + 1) * __chunk_size; break; } #if _GLIBCXX_PARALLEL_ASSERTIONS _GLIBCXX_PARALLEL_ASSERT(__swapstart != -1); #endif std::swap_ranges(__begin + __thread_left_border - (__chunk_size - 1), __begin + __thread_left_border + 1, __begin + __swapstart); } if (__thread_right >= __thread_right_border && __thread_right_border > __rightnew) { // Find spot and swap _DifferenceType __swapstart = -1; for (int __r = 0; __r < __leftover_right; ++__r) if (__reserved_right[__r] == 0 && __compare_and_swap(&(__reserved_right[__r]), 0, 1)) { __swapstart = __rightold + __r * __chunk_size + 1; break; } #if _GLIBCXX_PARALLEL_ASSERTIONS _GLIBCXX_PARALLEL_ASSERT(__swapstart != -1); #endif std::swap_ranges(__begin + __thread_right_border, __begin + __thread_right_border + __chunk_size, __begin + __swapstart); } #if _GLIBCXX_PARALLEL_ASSERTIONS # pragma omp barrier # pragma omp single { for (_DifferenceType __r = 0; __r < __leftover_left; ++__r) _GLIBCXX_PARALLEL_ASSERT(__reserved_left[__r] == 1); for (_DifferenceType __r = 0; __r < __leftover_right; ++__r) _GLIBCXX_PARALLEL_ASSERT(__reserved_right[__r] == 1); } #endif __left = __leftnew; __right = __rightnew; __dist = __right - __left + 1; } # pragma omp flush(__left, __right) } // end "recursion" //parallel _DifferenceType __final_left = __left, __final_right = __right; while (__final_left < __final_right) { // Go right until key is geq than pivot. while (__pred(__begin[__final_left]) && __final_left < __final_right) ++__final_left; // Go left until key is less than pivot. while (!__pred(__begin[__final_right]) && __final_left < __final_right) --__final_right; if (__final_left == __final_right) break; std::iter_swap(__begin + __final_left, __begin + __final_right); ++__final_left; --__final_right; } // All elements on the left side are < piv, all elements on the // right are >= piv delete[] __reserved_left; delete[] __reserved_right; // Element "between" __final_left and __final_right might not have // been regarded yet if (__final_left < __n && !__pred(__begin[__final_left])) // Really swapped. return __final_left; else return __final_left + 1; } /** * @brief Parallel implementation of std::nth_element(). * @param __begin Begin iterator of input sequence. * @param __nth _Iterator of element that must be in position afterwards. * @param __end End iterator of input sequence. * @param __comp Comparator. / template<typename _RAIter, typename _Compare> void __parallel_nth_element(_RAIter __begin, _RAIter __nth, _RAIter __end, _Compare __comp) { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; _GLIBCXX_CALL(__end - __begin) _RAIter __split; _RandomNumber __rng; const _Settings& __s = _Settings::get(); _DifferenceType __minimum_length = std::max<_DifferenceType>(2, std::max(__s.nth_element_minimal_n, __s.partition_minimal_n)); // Break if input range to small. while (static_cast<_SequenceIndex>(__end - __begin) >= __minimum_length) { _DifferenceType __n = __end - __begin; _RAIter __pivot_pos = __begin + __rng(__n); // Swap __pivot_pos value to end. if (__pivot_pos != (__end - 1)) std::iter_swap(__pivot_pos, __end - 1); __pivot_pos = __end - 1; // _Compare must have first_value_type, second_value_type, // result_type // _Compare == // __gnu_parallel::_Lexicographic<S, int, // __gnu_parallel::_Less<S, S> > // __pivot_pos == std::pair<S, int> __gnu_parallel::__binder2nd<_Compare, _ValueType, _ValueType, bool> __pred(__comp, __pivot_pos); // Divide, leave pivot unchanged in last place. _RAIter __split_pos1, __split_pos2; __split_pos1 = __begin + __parallel_partition(__begin, __end - 1, __pred, __get_max_threads()); // Left side: < __pivot_pos; __right side: >= __pivot_pos // Swap pivot back to middle. if (__split_pos1 != __pivot_pos) std::iter_swap(__split_pos1, __pivot_pos); __pivot_pos = __split_pos1; // In case all elements are equal, __split_pos1 == 0 if ((__split_pos1 + 1 - __begin) < (__n >> 7) \|\| (__end - __split_pos1) < (__n >> 7)) { // Very unequal split, one part smaller than one 128th // elements not strictly larger than the pivot. __gnu_parallel::__unary_negate<__gnu_parallel:: __binder1st<_Compare, _ValueType, _ValueType, bool>, _ValueType> __pred(__gnu_parallel::__binder1st<_Compare, _ValueType, _ValueType, bool>(__comp, __pivot_pos)); // Find other end of pivot-equal range. __split_pos2 = __gnu_sequential::partition(__split_pos1 + 1, __end, __pred); } else // Only skip the pivot. __split_pos2 = __split_pos1 + 1; // Compare iterators. if (__split_pos2 <= __nth) __begin = __split_pos2; else if (__nth < __split_pos1) __end = __split_pos1; else break; } // Only at most _Settings::partition_minimal_n __elements __left. __gnu_sequential::nth_element(__begin, __nth, __end, __comp); } /** @brief Parallel implementation of std::partial_sort(). * @param __begin Begin iterator of input sequence. * @param __middle Sort until this position. * @param __end End iterator of input sequence. * @param __comp Comparator. / template<typename _RAIter, typename _Compare> void __parallel_partial_sort(_RAIter __begin, _RAIter __middle, _RAIter __end, _Compare __comp) { __parallel_nth_element(__begin, __middle, __end, __comp); std::sort(__begin, __middle, __comp); } } //namespace __gnu_parallel #undef _GLIBCXX_VOLATILE #endif / _GLIBCXX_PARALLEL_PARTITION_H */	14.61 KB	2025-09-15 15:41
📄 queue.h // -- C++ -- // Copyright (C) 2007-2021 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/queue.h * @brief Lock-free double-ended queue. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_QUEUE_H #define _GLIBCXX_PARALLEL_QUEUE_H 1 #include <parallel/types.h> #include <parallel/base.h> #include <parallel/compatibility.h> /* @brief Decide whether to declare certain variable volatile in this file. / #define _GLIBCXX_VOLATILE volatile namespace __gnu_parallel { /@brief Double-ended queue of bounded size, allowing lock-free atomic access. push_front() and pop_front() must not be called * concurrently to each other, while pop_back() can be called * concurrently at all times. * @c empty(), @c size(), and @c top() are intentionally not provided. * Calling them would not make sense in a concurrent setting. * @param _Tp Contained element type. / template<typename _Tp> class _RestrictedBoundedConcurrentQueue { private: /* @brief Array of elements, seen as cyclic buffer. / _Tp _M_base; /** @brief Maximal number of elements contained at the same time. / _SequenceIndex _M_max_size; /* @brief Cyclic __begin and __end pointers contained in one atomically changeable value. / _GLIBCXX_VOLATILE _CASable _M_borders; public: /* @brief Constructor. Not to be called concurrent, of course. * @param __max_size Maximal number of elements to be contained. / _RestrictedBoundedConcurrentQueue(_SequenceIndex __max_size) { _M_max_size = __max_size; _M_base = new _Tp[__max_size]; _M_borders = __encode2(0, 0); #pragma omp flush } /* @brief Destructor. Not to be called concurrent, of course. / ~_RestrictedBoundedConcurrentQueue() { delete[] _M_base; } /* @brief Pushes one element into the queue at the front end. * Must not be called concurrently with pop_front(). / void push_front(const _Tp& __t) { _CASable __former_borders = _M_borders; int __former_front, __former_back; __decode2(__former_borders, __former_front, __former_back); (_M_base + __former_front % _M_max_size) = __t; #if _GLIBCXX_PARALLEL_ASSERTIONS // Otherwise: front - back > _M_max_size eventually. _GLIBCXX_PARALLEL_ASSERT(((__former_front + 1) - __former_back) <= _M_max_size); #endif __fetch_and_add(&_M_borders, __encode2(1, 0)); } /** @brief Pops one element from the queue at the front end. * Must not be called concurrently with pop_front(). / bool pop_front(_Tp& __t) { int __former_front, __former_back; #pragma omp flush __decode2(_M_borders, __former_front, __former_back); while (__former_front > __former_back) { // Chance. _CASable __former_borders = __encode2(__former_front, __former_back); _CASable __new_borders = __encode2(__former_front - 1, __former_back); if (__compare_and_swap(&_M_borders, __former_borders, __new_borders)) { __t = (_M_base + (__former_front - 1) % _M_max_size); return true; } #pragma omp flush __decode2(_M_borders, __former_front, __former_back); } return false; } /** @brief Pops one element from the queue at the front end. * Must not be called concurrently with pop_front(). / bool pop_back(_Tp& __t) //queue behavior { int __former_front, __former_back; #pragma omp flush __decode2(_M_borders, __former_front, __former_back); while (__former_front > __former_back) { // Chance. _CASable __former_borders = __encode2(__former_front, __former_back); _CASable __new_borders = __encode2(__former_front, __former_back + 1); if (__compare_and_swap(&_M_borders, __former_borders, __new_borders)) { __t = (_M_base + __former_back % _M_max_size); return true; } #pragma omp flush __decode2(_M_borders, __former_front, __former_back); } return false; } }; } //namespace __gnu_parallel #undef _GLIBCXX_VOLATILE #endif /* _GLIBCXX_PARALLEL_QUEUE_H */	5.41 KB	2025-09-15 15:41
📄 quicksort.h // -- C++ -- // Copyright (C) 2007-2021 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/quicksort.h * @brief Implementation of a unbalanced parallel quicksort (in-place). * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_QUICKSORT_H #define _GLIBCXX_PARALLEL_QUICKSORT_H 1 #include <parallel/parallel.h> #include <parallel/partition.h> namespace __gnu_parallel { /* @brief Unbalanced quicksort divide step. * @param __begin Begin iterator of subsequence. * @param __end End iterator of subsequence. * @param __comp Comparator. * @param __pivot_rank Desired __rank of the pivot. * @param __num_samples Choose pivot from that many samples. * @param __num_threads Number of threads that are allowed to work on * this part. / template<typename _RAIter, typename _Compare> typename std::iterator_traits<_RAIter>::difference_type __parallel_sort_qs_divide(_RAIter __begin, _RAIter __end, _Compare __comp, typename std::iterator_traits <_RAIter>::difference_type __pivot_rank, typename std::iterator_traits <_RAIter>::difference_type __num_samples, _ThreadIndex __num_threads) { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; _DifferenceType __n = __end - __begin; __num_samples = std::min(__num_samples, __n); // Allocate uninitialized, to avoid default constructor. _ValueType __samples = static_cast<_ValueType> (::operator new(__num_samples sizeof(_ValueType))); for (_DifferenceType __s = 0; __s < __num_samples; ++__s) { const unsigned long long __index = static_cast<unsigned long long> (__s) * __n / __num_samples; ::new(&(__samples[__s])) _ValueType(__begin[__index]); } __gnu_sequential::sort(__samples, __samples + __num_samples, __comp); _ValueType& __pivot = __samples[__pivot_rank * __num_samples / __n]; __gnu_parallel::__binder2nd<_Compare, _ValueType, _ValueType, bool> __pred(__comp, __pivot); _DifferenceType __split = __parallel_partition(__begin, __end, __pred, __num_threads); for (_DifferenceType __s = 0; __s < __num_samples; ++__s) __samples[__s].~_ValueType(); ::operator delete(__samples); return __split; } /** @brief Unbalanced quicksort conquer step. * @param __begin Begin iterator of subsequence. * @param __end End iterator of subsequence. * @param __comp Comparator. * @param __num_threads Number of threads that are allowed to work on * this part. / template<typename _RAIter, typename _Compare> void __parallel_sort_qs_conquer(_RAIter __begin, _RAIter __end, _Compare __comp, _ThreadIndex __num_threads) { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; if (__num_threads <= 1) { __gnu_sequential::sort(__begin, __end, __comp); return; } _DifferenceType __n = __end - __begin, __pivot_rank; if (__n <= 1) return; _ThreadIndex __num_threads_left; if ((__num_threads % 2) == 1) __num_threads_left = __num_threads / 2 + 1; else __num_threads_left = __num_threads / 2; __pivot_rank = __n __num_threads_left / __num_threads; _DifferenceType __split = __parallel_sort_qs_divide (__begin, __end, __comp, __pivot_rank, _Settings::get().sort_qs_num_samples_preset, __num_threads); #pragma omp parallel sections num_threads(2) { #pragma omp section __parallel_sort_qs_conquer(__begin, __begin + __split, __comp, __num_threads_left); #pragma omp section __parallel_sort_qs_conquer(__begin + __split, __end, __comp, __num_threads - __num_threads_left); } } /** @brief Unbalanced quicksort main call. * @param __begin Begin iterator of input sequence. * @param __end End iterator input sequence, ignored. * @param __comp Comparator. * @param __num_threads Number of threads that are allowed to work on * this part. / template<typename _RAIter, typename _Compare> void __parallel_sort_qs(_RAIter __begin, _RAIter __end, _Compare __comp, _ThreadIndex __num_threads) { _GLIBCXX_CALL(__n) typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; _DifferenceType __n = __end - __begin; // At least one element per processor. if (__num_threads > __n) __num_threads = static_cast<_ThreadIndex>(__n); __parallel_sort_qs_conquer( __begin, __begin + __n, __comp, __num_threads); } } //namespace __gnu_parallel #endif / _GLIBCXX_PARALLEL_QUICKSORT_H */	5.98 KB	2025-09-15 15:41
📄 random_number.h // -- C++ -- // Copyright (C) 2007-2021 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/random_number.h * @brief Random number generator based on the Mersenne twister. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_RANDOM_NUMBER_H #define _GLIBCXX_PARALLEL_RANDOM_NUMBER_H 1 #include <parallel/types.h> #include <tr1/random> #include <limits> namespace __gnu_parallel { /* @brief Random number generator, based on the Mersenne twister. / class _RandomNumber { private: std::tr1::mt19937 _M_mt; uint64_t _M_supremum; uint64_t _M_rand_sup; double _M_supremum_reciprocal; double _M_rand_sup_reciprocal; // Assumed to be twice as long as the usual random number. uint64_t __cache; // Bit results. int __bits_left; static uint32_t __scale_down(uint64_t __x, #if _GLIBCXX_SCALE_DOWN_FPU uint64_t /_M_supremum/, double _M_supremum_reciprocal) #else uint64_t _M_supremum, double /_M_supremum_reciprocal/) #endif { #if _GLIBCXX_SCALE_DOWN_FPU return uint32_t(__x _M_supremum_reciprocal); #else return static_cast<uint32_t>(__x % _M_supremum); #endif } public: /** @brief Default constructor. Seed with 0. / _RandomNumber() : _M_mt(0), _M_supremum(0x100000000ULL), _M_rand_sup(1ULL << std::numeric_limits<uint32_t>::digits), _M_supremum_reciprocal(double(_M_supremum) / double(_M_rand_sup)), _M_rand_sup_reciprocal(1.0 / double(_M_rand_sup)), __cache(0), __bits_left(0) { } /* @brief Constructor. * @param __seed Random __seed. * @param _M_supremum Generate integer random numbers in the * interval @c [0,_M_supremum). / _RandomNumber(uint32_t __seed, uint64_t _M_supremum = 0x100000000ULL) : _M_mt(__seed), _M_supremum(_M_supremum), _M_rand_sup(1ULL << std::numeric_limits<uint32_t>::digits), _M_supremum_reciprocal(double(_M_supremum) / double(_M_rand_sup)), _M_rand_sup_reciprocal(1.0 / double(_M_rand_sup)), __cache(0), __bits_left(0) { } /* @brief Generate unsigned random 32-bit integer. / uint32_t operator()() { return __scale_down(_M_mt(), _M_supremum, _M_supremum_reciprocal); } /* @brief Generate unsigned random 32-bit integer in the interval @c [0,local_supremum). / uint32_t operator()(uint64_t local_supremum) { return __scale_down(_M_mt(), local_supremum, double(local_supremum _M_rand_sup_reciprocal)); } /** @brief Generate a number of random bits, run-time parameter. * @param __bits Number of bits to generate. / unsigned long __genrand_bits(int __bits) { unsigned long __res = __cache & ((1 << __bits) - 1); __cache = __cache >> __bits; __bits_left -= __bits; if (__bits_left < 32) { __cache \|= ((uint64_t(_M_mt())) << __bits_left); __bits_left += 32; } return __res; } }; } // namespace __gnu_parallel #endif / _GLIBCXX_PARALLEL_RANDOM_NUMBER_H */	4.13 KB	2025-09-15 15:41
📄 random_shuffle.h // -- C++ -- // Copyright (C) 2007-2021 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/random_shuffle.h * @brief Parallel implementation of std::random_shuffle(). * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_RANDOM_SHUFFLE_H #define _GLIBCXX_PARALLEL_RANDOM_SHUFFLE_H 1 #include <limits> #include <bits/stl_numeric.h> #include <parallel/parallel.h> #include <parallel/random_number.h> namespace __gnu_parallel { /* @brief Type to hold the index of a bin. * * Since many variables of this type are allocated, it should be * chosen as small as possible. / typedef unsigned short _BinIndex; /* @brief Data known to every thread participating in __gnu_parallel::__parallel_random_shuffle(). / template<typename _RAIter> struct _DRandomShufflingGlobalData { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; /* @brief Begin iterator of the __source. / _RAIter& _M_source; /* @brief Temporary arrays for each thread. / _ValueType* _M_temporaries; /** @brief Two-dimensional array to hold the thread-bin distribution. * * Dimensions (_M_num_threads + 1) __x (_M_num_bins + 1). / _DifferenceType* _M_dist; /** @brief Start indexes of the threads' __chunks. / _DifferenceType _M_starts; /** @brief Number of the thread that will further process the corresponding bin. / _ThreadIndex _M_bin_proc; /** @brief Number of bins to distribute to. / int _M_num_bins; /* @brief Number of bits needed to address the bins. / int _M_num_bits; /* @brief Constructor. / _DRandomShufflingGlobalData(_RAIter& __source) : _M_source(__source) { } }; /* @brief Local data for a thread participating in __gnu_parallel::__parallel_random_shuffle(). / template<typename _RAIter, typename _RandomNumberGenerator> struct _DRSSorterPU { /* @brief Number of threads participating in total. / int _M_num_threads; /* @brief Begin index for bins taken care of by this thread. / _BinIndex _M_bins_begin; /* @brief End index for bins taken care of by this thread. / _BinIndex __bins_end; /* @brief Random _M_seed for this thread. / uint32_t _M_seed; /* @brief Pointer to global data. / _DRandomShufflingGlobalData<_RAIter> _M_sd; }; /** @brief Generate a random number in @c [0,2^__logp). * @param __logp Logarithm (basis 2) of the upper range __bound. * @param __rng Random number generator to use. / template<typename _RandomNumberGenerator> inline int __random_number_pow2(int __logp, _RandomNumberGenerator& __rng) { return __rng.__genrand_bits(__logp); } /* @brief Random shuffle code executed by each thread. * @param __pus Array of thread-local data records. / template<typename _RAIter, typename _RandomNumberGenerator> void __parallel_random_shuffle_drs_pu(_DRSSorterPU<_RAIter, _RandomNumberGenerator> __pus) { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; _ThreadIndex __iam = omp_get_thread_num(); _DRSSorterPU<_RAIter, _RandomNumberGenerator>* __d = &__pus[__iam]; _DRandomShufflingGlobalData<_RAIter>* __sd = __d->_M_sd; // Indexing: _M_dist[bin][processor] _DifferenceType __length = (__sd->_M_starts[__iam + 1] - __sd->_M_starts[__iam]); _BinIndex* __oracles = new _BinIndex[__length]; _DifferenceType* __dist = new _DifferenceType[__sd->_M_num_bins + 1]; _BinIndex* __bin_proc = new _BinIndex[__sd->_M_num_bins]; _ValueType** __temporaries = new _ValueType[__d->_M_num_threads]; // Compute oracles and count appearances. for (_BinIndex __b = 0; __b < __sd->_M_num_bins + 1; ++__b) __dist[__b] = 0; int __num_bits = __sd->_M_num_bits; _RandomNumber __rng(__d->_M_seed); // First main loop. for (_DifferenceType __i = 0; __i < __length; ++__i) { _BinIndex __oracle = __random_number_pow2(__num_bits, __rng); __oracles[__i] = __oracle; // To allow prefix (partial) sum. ++(__dist[__oracle + 1]); } for (_BinIndex __b = 0; __b < __sd->_M_num_bins + 1; ++__b) __sd->_M_dist[__b][__iam + 1] = __dist[__b]; # pragma omp barrier # pragma omp single { // Sum up bins, __sd->_M_dist[__s + 1][__d->_M_num_threads] now // contains the total number of items in bin __s for (_BinIndex __s = 0; __s < __sd->_M_num_bins; ++__s) __gnu_sequential::partial_sum(__sd->_M_dist[__s + 1], __sd->_M_dist[__s + 1] + __d->_M_num_threads + 1, __sd->_M_dist[__s + 1]); } # pragma omp barrier _SequenceIndex __offset = 0, __global_offset = 0; for (_BinIndex __s = 0; __s < __d->_M_bins_begin; ++__s) __global_offset += __sd->_M_dist[__s + 1][__d->_M_num_threads]; # pragma omp barrier for (_BinIndex __s = __d->_M_bins_begin; __s < __d->__bins_end; ++__s) { for (int __t = 0; __t < __d->_M_num_threads + 1; ++__t) __sd->_M_dist[__s + 1][__t] += __offset; __offset = __sd->_M_dist[__s + 1][__d->_M_num_threads]; } __sd->_M_temporaries[__iam] = static_cast<_ValueType> (::operator new(sizeof(_ValueType) * __offset)); # pragma omp barrier // Draw local copies to avoid false sharing. for (_BinIndex __b = 0; __b < __sd->_M_num_bins + 1; ++__b) __dist[__b] = __sd->_M_dist[__b][__iam]; for (_BinIndex __b = 0; __b < __sd->_M_num_bins; ++__b) __bin_proc[__b] = __sd->_M_bin_proc[__b]; for (_ThreadIndex __t = 0; __t < __d->_M_num_threads; ++__t) __temporaries[__t] = __sd->_M_temporaries[__t]; _RAIter __source = __sd->_M_source; _DifferenceType __start = __sd->_M_starts[__iam]; // Distribute according to oracles, second main loop. for (_DifferenceType __i = 0; __i < __length; ++__i) { _BinIndex __target_bin = __oracles[__i]; _ThreadIndex __target_p = __bin_proc[__target_bin]; // Last column [__d->_M_num_threads] stays unchanged. ::new(&(__temporaries[__target_p][__dist[__target_bin + 1]++])) _ValueType((__source + __i + __start)); } delete[] __oracles; delete[] __dist; delete[] __bin_proc; delete[] __temporaries; # pragma omp barrier // Shuffle bins internally. for (_BinIndex __b = __d->_M_bins_begin; __b < __d->__bins_end; ++__b) { _ValueType __begin = (__sd->_M_temporaries[__iam] + (__b == __d->_M_bins_begin ? 0 : __sd->_M_dist[__b][__d->_M_num_threads])), __end = (__sd->_M_temporaries[__iam] + __sd->_M_dist[__b + 1][__d->_M_num_threads]); __sequential_random_shuffle(__begin, __end, __rng); std::copy(__begin, __end, __sd->_M_source + __global_offset + (__b == __d->_M_bins_begin ? 0 : __sd->_M_dist[__b][__d->_M_num_threads])); } for (_SequenceIndex __i = 0; __i < __offset; ++__i) __sd->_M_temporaries[__iam][__i].~_ValueType(); ::operator delete(__sd->_M_temporaries[__iam]); } /* @brief Round up to the next greater power of 2. * @param __x _Integer to round up / template<typename _Tp> _Tp __round_up_to_pow2(_Tp __x) { if (__x <= 1) return 1; else return (_Tp)1 << (__rd_log2(__x - 1) + 1); } /* @brief Main parallel random shuffle step. * @param __begin Begin iterator of sequence. * @param __end End iterator of sequence. * @param __n Length of sequence. * @param __num_threads Number of threads to use. * @param __rng Random number generator to use. / template<typename _RAIter, typename _RandomNumberGenerator> void __parallel_random_shuffle_drs(_RAIter __begin, _RAIter __end, typename std::iterator_traits <_RAIter>::difference_type __n, _ThreadIndex __num_threads, _RandomNumberGenerator& __rng) { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; _GLIBCXX_CALL(__n) const _Settings& __s = _Settings::get(); if (__num_threads > __n) __num_threads = static_cast<_ThreadIndex>(__n); _BinIndex __num_bins, __num_bins_cache; #if _GLIBCXX_RANDOM_SHUFFLE_CONSIDER_L1 // Try the L1 cache first. // Must fit into L1. __num_bins_cache = std::max<_DifferenceType>(1, __n / (__s.L1_cache_size_lb / sizeof(_ValueType))); __num_bins_cache = __round_up_to_pow2(__num_bins_cache); // No more buckets than TLB entries, power of 2 // Power of 2 and at least one element per bin, at most the TLB size. __num_bins = std::min<_DifferenceType>(__n, __num_bins_cache); #if _GLIBCXX_RANDOM_SHUFFLE_CONSIDER_TLB // 2 TLB entries needed per bin. __num_bins = std::min<_DifferenceType>(__s.TLB_size / 2, __num_bins); #endif __num_bins = __round_up_to_pow2(__num_bins); if (__num_bins < __num_bins_cache) { #endif // Now try the L2 cache // Must fit into L2 __num_bins_cache = static_cast<_BinIndex> (std::max<_DifferenceType>(1, __n / (__s.L2_cache_size / sizeof(_ValueType)))); __num_bins_cache = __round_up_to_pow2(__num_bins_cache); // No more buckets than TLB entries, power of 2. __num_bins = static_cast<_BinIndex> (std::min(__n, static_cast<_DifferenceType>(__num_bins_cache))); // Power of 2 and at least one element per bin, at most the TLB size. #if _GLIBCXX_RANDOM_SHUFFLE_CONSIDER_TLB // 2 TLB entries needed per bin. __num_bins = std::min(static_cast<_DifferenceType>(__s.TLB_size / 2), __num_bins); #endif __num_bins = __round_up_to_pow2(__num_bins); #if _GLIBCXX_RANDOM_SHUFFLE_CONSIDER_L1 } #endif __num_bins = __round_up_to_pow2( std::max<_BinIndex>(__num_threads, __num_bins)); if (__num_threads <= 1) { _RandomNumber __derived_rng( __rng(std::numeric_limits<uint32_t>::max())); __sequential_random_shuffle(__begin, __end, __derived_rng); return; } _DRandomShufflingGlobalData<_RAIter> __sd(__begin); _DRSSorterPU<_RAIter, _RandomNumber > __pus; _DifferenceType* __starts; # pragma omp parallel num_threads(__num_threads) { _ThreadIndex __num_threads = omp_get_num_threads(); # pragma omp single { __pus = new _DRSSorterPU<_RAIter, _RandomNumber>[__num_threads]; __sd._M_temporaries = new _ValueType[__num_threads]; __sd._M_dist = new _DifferenceType[__num_bins + 1]; __sd._M_bin_proc = new _ThreadIndex[__num_bins]; for (_BinIndex __b = 0; __b < __num_bins + 1; ++__b) __sd._M_dist[__b] = new _DifferenceType[__num_threads + 1]; for (_BinIndex __b = 0; __b < (__num_bins + 1); ++__b) { __sd._M_dist[0][0] = 0; __sd._M_dist[__b][0] = 0; } __starts = __sd._M_starts = new _DifferenceType[__num_threads + 1]; int __bin_cursor = 0; __sd._M_num_bins = __num_bins; __sd._M_num_bits = __rd_log2(__num_bins); _DifferenceType __chunk_length = __n / __num_threads, __split = __n % __num_threads, __start = 0; _DifferenceType __bin_chunk_length = __num_bins / __num_threads, __bin_split = __num_bins % __num_threads; for (_ThreadIndex __i = 0; __i < __num_threads; ++__i) { __starts[__i] = __start; __start += (__i < __split ? (__chunk_length + 1) : __chunk_length); int __j = __pus[__i]._M_bins_begin = __bin_cursor; // Range of bins for this processor. __bin_cursor += (__i < __bin_split ? (__bin_chunk_length + 1) : __bin_chunk_length); __pus[__i].__bins_end = __bin_cursor; for (; __j < __bin_cursor; ++__j) __sd._M_bin_proc[__j] = __i; __pus[__i]._M_num_threads = __num_threads; __pus[__i]._M_seed = __rng(std::numeric_limits<uint32_t>::max()); __pus[__i]._M_sd = &__sd; } __starts[__num_threads] = __start; } //single // Now shuffle in parallel. __parallel_random_shuffle_drs_pu(__pus); } // parallel delete[] __starts; delete[] __sd._M_bin_proc; for (int __s = 0; __s < (__num_bins + 1); ++__s) delete[] __sd._M_dist[__s]; delete[] __sd._M_dist; delete[] __sd._M_temporaries; delete[] __pus; } /** @brief Sequential cache-efficient random shuffle. * @param __begin Begin iterator of sequence. * @param __end End iterator of sequence. * @param __rng Random number generator to use. / template<typename _RAIter, typename _RandomNumberGenerator> void __sequential_random_shuffle(_RAIter __begin, _RAIter __end, _RandomNumberGenerator& __rng) { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; _DifferenceType __n = __end - __begin; const _Settings& __s = _Settings::get(); _BinIndex __num_bins, __num_bins_cache; #if _GLIBCXX_RANDOM_SHUFFLE_CONSIDER_L1 // Try the L1 cache first, must fit into L1. __num_bins_cache = std::max<_DifferenceType> (1, __n / (__s.L1_cache_size_lb / sizeof(_ValueType))); __num_bins_cache = __round_up_to_pow2(__num_bins_cache); // No more buckets than TLB entries, power of 2 // Power of 2 and at least one element per bin, at most the TLB size __num_bins = std::min(__n, (_DifferenceType)__num_bins_cache); #if _GLIBCXX_RANDOM_SHUFFLE_CONSIDER_TLB // 2 TLB entries needed per bin __num_bins = std::min((_DifferenceType)__s.TLB_size / 2, __num_bins); #endif __num_bins = __round_up_to_pow2(__num_bins); if (__num_bins < __num_bins_cache) { #endif // Now try the L2 cache, must fit into L2. __num_bins_cache = static_cast<_BinIndex> (std::max<_DifferenceType>(1, __n / (__s.L2_cache_size / sizeof(_ValueType)))); __num_bins_cache = __round_up_to_pow2(__num_bins_cache); // No more buckets than TLB entries, power of 2 // Power of 2 and at least one element per bin, at most the TLB size. __num_bins = static_cast<_BinIndex> (std::min(__n, static_cast<_DifferenceType>(__num_bins_cache))); #if _GLIBCXX_RANDOM_SHUFFLE_CONSIDER_TLB // 2 TLB entries needed per bin __num_bins = std::min<_DifferenceType>(__s.TLB_size / 2, __num_bins); #endif __num_bins = __round_up_to_pow2(__num_bins); #if _GLIBCXX_RANDOM_SHUFFLE_CONSIDER_L1 } #endif int __num_bits = __rd_log2(__num_bins); if (__num_bins > 1) { _ValueType __target = static_cast<_ValueType>(::operator new(sizeof(_ValueType) __n)); _BinIndex* __oracles = new _BinIndex[__n]; _DifferenceType* __dist0 = new _DifferenceType[__num_bins + 1], * __dist1 = new _DifferenceType[__num_bins + 1]; for (int __b = 0; __b < __num_bins + 1; ++__b) __dist0[__b] = 0; _RandomNumber __bitrng(__rng(0xFFFFFFFF)); for (_DifferenceType __i = 0; __i < __n; ++__i) { _BinIndex __oracle = __random_number_pow2(__num_bits, __bitrng); __oracles[__i] = __oracle; // To allow prefix (partial) sum. ++(__dist0[__oracle + 1]); } // Sum up bins. __gnu_sequential::partial_sum(__dist0, __dist0 + __num_bins + 1, __dist0); for (int __b = 0; __b < __num_bins + 1; ++__b) __dist1[__b] = __dist0[__b]; // Distribute according to oracles. for (_DifferenceType __i = 0; __i < __n; ++__i) ::new(&(__target[(__dist0[__oracles[__i]])++])) _ValueType((__begin + __i)); for (int __b = 0; __b < __num_bins; ++__b) __sequential_random_shuffle(__target + __dist1[__b], __target + __dist1[__b + 1], __rng); // Copy elements back. std::copy(__target, __target + __n, __begin); delete[] __dist0; delete[] __dist1; delete[] __oracles; for (_DifferenceType __i = 0; __i < __n; ++__i) __target[__i].~_ValueType(); ::operator delete(__target); } else __gnu_sequential::random_shuffle(__begin, __end, __rng); } /* @brief Parallel random public call. * @param __begin Begin iterator of sequence. * @param __end End iterator of sequence. * @param __rng Random number generator to use. / template<typename _RAIter, typename _RandomNumberGenerator> inline void __parallel_random_shuffle(_RAIter __begin, _RAIter __end, _RandomNumberGenerator __rng = _RandomNumber()) { typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::difference_type _DifferenceType; _DifferenceType __n = __end - __begin; __parallel_random_shuffle_drs(__begin, __end, __n, __get_max_threads(), __rng); } } #endif / _GLIBCXX_PARALLEL_RANDOM_SHUFFLE_H */	18.24 KB	2025-09-15 15:41
📄 search.h // -- C++ -- // Copyright (C) 2007-2021 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/search.h * @brief Parallel implementation base for std::search() and * std::search_n(). * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Felix Putze. #ifndef _GLIBCXX_PARALLEL_SEARCH_H #define _GLIBCXX_PARALLEL_SEARCH_H 1 #include <bits/stl_algobase.h> #include <parallel/parallel.h> #include <parallel/equally_split.h> namespace __gnu_parallel { /* * @brief Precalculate __advances for Knuth-Morris-Pratt algorithm. * @param __elements Begin iterator of sequence to search for. * @param __length Length of sequence to search for. * @param __off Returned __offsets. / template<typename _RAIter, typename _DifferenceTp> void __calc_borders(_RAIter __elements, _DifferenceTp __length, _DifferenceTp __off) { typedef _DifferenceTp _DifferenceType; __off[0] = -1; if (__length > 1) __off[1] = 0; _DifferenceType __k = 0; for (_DifferenceType __j = 2; __j <= __length; __j++) { while ((__k >= 0) && !(__elements[__k] == __elements[__j-1])) __k = __off[__k]; __off[__j] = ++__k; } } // Generic parallel find algorithm (requires random access iterator). /** @brief Parallel std::search. * @param __begin1 Begin iterator of first sequence. * @param __end1 End iterator of first sequence. * @param __begin2 Begin iterator of second sequence. * @param __end2 End iterator of second sequence. * @param __pred Find predicate. * @return Place of finding in first sequences. / template<typename __RAIter1, typename __RAIter2, typename _Pred> __RAIter1 __search_template(__RAIter1 __begin1, __RAIter1 __end1, __RAIter2 __begin2, __RAIter2 __end2, _Pred __pred) { typedef std::iterator_traits<__RAIter1> _TraitsType; typedef typename _TraitsType::difference_type _DifferenceType; _GLIBCXX_CALL((__end1 - __begin1) + (__end2 - __begin2)); _DifferenceType __pattern_length = __end2 - __begin2; // Pattern too short. if(__pattern_length <= 0) return __end1; // Last point to start search. _DifferenceType __input_length = (__end1 - __begin1) - __pattern_length; // Where is first occurrence of pattern? defaults to end. _DifferenceType __result = (__end1 - __begin1); _DifferenceType __splitters; // Pattern too long. if (__input_length < 0) return __end1; omp_lock_t __result_lock; omp_init_lock(&__result_lock); _ThreadIndex __num_threads = std::max<_DifferenceType> (1, std::min<_DifferenceType>(__input_length, __get_max_threads())); _DifferenceType __advances[__pattern_length]; __calc_borders(__begin2, __pattern_length, __advances); # pragma omp parallel num_threads(__num_threads) { # pragma omp single { __num_threads = omp_get_num_threads(); __splitters = new _DifferenceType[__num_threads + 1]; __equally_split(__input_length, __num_threads, __splitters); } _ThreadIndex __iam = omp_get_thread_num(); _DifferenceType __start = __splitters[__iam], __stop = __splitters[__iam + 1]; _DifferenceType __pos_in_pattern = 0; bool __found_pattern = false; while (__start <= __stop && !__found_pattern) { // Get new value of result. #pragma omp flush(__result) // No chance for this thread to find first occurrence. if (__result < __start) break; while (__pred(__begin1[__start + __pos_in_pattern], __begin2[__pos_in_pattern])) { ++__pos_in_pattern; if (__pos_in_pattern == __pattern_length) { // Found new candidate for result. omp_set_lock(&__result_lock); __result = std::min(__result, __start); omp_unset_lock(&__result_lock); __found_pattern = true; break; } } // Make safe jump. __start += (__pos_in_pattern - __advances[__pos_in_pattern]); __pos_in_pattern = (__advances[__pos_in_pattern] < 0 ? 0 : __advances[__pos_in_pattern]); } } //parallel omp_destroy_lock(&__result_lock); delete[] __splitters; // Return iterator on found element. return (__begin1 + __result); } } // end namespace #endif /* _GLIBCXX_PARALLEL_SEARCH_H */	5.26 KB	2025-09-15 15:41
📄 set_operations.h // -- C++ -- // Copyright (C) 2007-2021 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/set_operations.h * @brief Parallel implementations of set operations for random-access * iterators. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Marius Elvert and Felix Bondarenko. #ifndef _GLIBCXX_PARALLEL_SET_OPERATIONS_H #define _GLIBCXX_PARALLEL_SET_OPERATIONS_H 1 #include <omp.h> #include <parallel/settings.h> #include <parallel/multiseq_selection.h> namespace __gnu_parallel { template<typename _IIter, typename _OutputIterator> _OutputIterator __copy_tail(std::pair<_IIter, _IIter> __b, std::pair<_IIter, _IIter> __e, _OutputIterator __r) { if (__b.first != __e.first) { do { __r++ = __b.first++; } while (__b.first != __e.first); } else { while (__b.second != __e.second) __r++ = __b.second++; } return __r; } template<typename _IIter, typename _OutputIterator, typename _Compare> struct __symmetric_difference_func { typedef std::iterator_traits<_IIter> _TraitsType; typedef typename _TraitsType::difference_type _DifferenceType; typedef typename std::pair<_IIter, _IIter> _IteratorPair; __symmetric_difference_func(_Compare __comp) : _M_comp(__comp) {} _Compare _M_comp; _OutputIterator _M_invoke(_IIter __a, _IIter __b, _IIter __c, _IIter __d, _OutputIterator __r) const { while (__a != __b && __c != __d) { if (_M_comp(__a, __c)) { __r = __a; ++__a; ++__r; } else if (_M_comp(__c, __a)) { __r = __c; ++__c; ++__r; } else { ++__a; ++__c; } } return std::copy(__c, __d, std::copy(__a, __b, __r)); } _DifferenceType __count(_IIter __a, _IIter __b, _IIter __c, _IIter __d) const { _DifferenceType __counter = 0; while (__a != __b && __c != __d) { if (_M_comp(__a, __c)) { ++__a; ++__counter; } else if (_M_comp(__c, __a)) { ++__c; ++__counter; } else { ++__a; ++__c; } } return __counter + (__b - __a) + (__d - __c); } _OutputIterator __first_empty(_IIter __c, _IIter __d, _OutputIterator __out) const { return std::copy(__c, __d, __out); } _OutputIterator __second_empty(_IIter __a, _IIter __b, _OutputIterator __out) const { return std::copy(__a, __b, __out); } }; template<typename _IIter, typename _OutputIterator, typename _Compare> struct __difference_func { typedef std::iterator_traits<_IIter> _TraitsType; typedef typename _TraitsType::difference_type _DifferenceType; typedef typename std::pair<_IIter, _IIter> _IteratorPair; __difference_func(_Compare __comp) : _M_comp(__comp) {} _Compare _M_comp; _OutputIterator _M_invoke(_IIter __a, _IIter __b, _IIter __c, _IIter __d, _OutputIterator __r) const { while (__a != __b && __c != __d) { if (_M_comp(__a, __c)) { __r = __a; ++__a; ++__r; } else if (_M_comp(__c, __a)) { ++__c; } else { ++__a; ++__c; } } return std::copy(__a, __b, __r); } _DifferenceType __count(_IIter __a, _IIter __b, _IIter __c, _IIter __d) const { _DifferenceType __counter = 0; while (__a != __b && __c != __d) { if (_M_comp(__a, __c)) { ++__a; ++__counter; } else if (_M_comp(__c, __a)) { ++__c; } else { ++__a; ++__c; } } return __counter + (__b - __a); } _OutputIterator __first_empty(_IIter, _IIter, _OutputIterator __out) const { return __out; } _OutputIterator __second_empty(_IIter __a, _IIter __b, _OutputIterator __out) const { return std::copy(__a, __b, __out); } }; template<typename _IIter, typename _OutputIterator, typename _Compare> struct __intersection_func { typedef std::iterator_traits<_IIter> _TraitsType; typedef typename _TraitsType::difference_type _DifferenceType; typedef typename std::pair<_IIter, _IIter> _IteratorPair; __intersection_func(_Compare __comp) : _M_comp(__comp) {} _Compare _M_comp; _OutputIterator _M_invoke(_IIter __a, _IIter __b, _IIter __c, _IIter __d, _OutputIterator __r) const { while (__a != __b && __c != __d) { if (_M_comp(__a, __c)) { ++__a; } else if (_M_comp(__c, __a)) { ++__c; } else { __r = __a; ++__a; ++__c; ++__r; } } return __r; } _DifferenceType __count(_IIter __a, _IIter __b, _IIter __c, _IIter __d) const { _DifferenceType __counter = 0; while (__a != __b && __c != __d) { if (_M_comp(__a, __c)) { ++__a; } else if (_M_comp(__c, __a)) { ++__c; } else { ++__a; ++__c; ++__counter; } } return __counter; } _OutputIterator __first_empty(_IIter, _IIter, _OutputIterator __out) const { return __out; } _OutputIterator __second_empty(_IIter, _IIter, _OutputIterator __out) const { return __out; } }; template<class _IIter, class _OutputIterator, class _Compare> struct __union_func { typedef typename std::iterator_traits<_IIter>::difference_type _DifferenceType; __union_func(_Compare __comp) : _M_comp(__comp) {} _Compare _M_comp; _OutputIterator _M_invoke(_IIter __a, const _IIter __b, _IIter __c, const _IIter __d, _OutputIterator __r) const { while (__a != __b && __c != __d) { if (_M_comp(__a, __c)) { __r = __a; ++__a; } else if (_M_comp(__c, __a)) { __r = __c; ++__c; } else { __r = __a; ++__a; ++__c; } ++__r; } return std::copy(__c, __d, std::copy(__a, __b, __r)); } _DifferenceType __count(_IIter __a, _IIter __b, _IIter __c, _IIter __d) const { _DifferenceType __counter = 0; while (__a != __b && __c != __d) { if (_M_comp(__a, __c)) { ++__a; } else if (_M_comp(__c, __a)) { ++__c; } else { ++__a; ++__c; } ++__counter; } __counter += (__b - __a); __counter += (__d - __c); return __counter; } _OutputIterator __first_empty(_IIter __c, _IIter __d, _OutputIterator __out) const { return std::copy(__c, __d, __out); } _OutputIterator __second_empty(_IIter __a, _IIter __b, _OutputIterator __out) const { return std::copy(__a, __b, __out); } }; template<typename _IIter, typename _OutputIterator, typename _Operation> _OutputIterator __parallel_set_operation(_IIter __begin1, _IIter __end1, _IIter __begin2, _IIter __end2, _OutputIterator __result, _Operation __op) { _GLIBCXX_CALL((__end1 - __begin1) + (__end2 - __begin2)) typedef std::iterator_traits<_IIter> _TraitsType; typedef typename _TraitsType::difference_type _DifferenceType; typedef typename std::pair<_IIter, _IIter> _IteratorPair; if (__begin1 == __end1) return __op.__first_empty(__begin2, __end2, __result); if (__begin2 == __end2) return __op.__second_empty(__begin1, __end1, __result); const _DifferenceType __size = (__end1 - __begin1) + (__end2 - __begin2); const _IteratorPair __sequence[2] = { std::make_pair(__begin1, __end1), std::make_pair(__begin2, __end2) }; _OutputIterator __return_value = __result; _DifferenceType __borders; _IteratorPair __block_begins; _DifferenceType __lengths; _ThreadIndex __num_threads = std::min<_DifferenceType>(__get_max_threads(), std::min(__end1 - __begin1, __end2 - __begin2)); # pragma omp parallel num_threads(__num_threads) { # pragma omp single { __num_threads = omp_get_num_threads(); __borders = new _DifferenceType[__num_threads + 2]; __equally_split(__size, __num_threads + 1, __borders); __block_begins = new _IteratorPair[__num_threads + 1]; // Very __start. __block_begins[0] = std::make_pair(__begin1, __begin2); __lengths = new _DifferenceType[__num_threads]; } //single _ThreadIndex __iam = omp_get_thread_num(); // _Result from multiseq_partition. _IIter __offset[2]; const _DifferenceType __rank = __borders[__iam + 1]; multiseq_partition(__sequence, __sequence + 2, __rank, __offset, __op._M_comp); // allowed to read? // together // (__offset[ 0 ] - 1) == __offset[ 1 ] if (__offset[ 0 ] != __begin1 && __offset[1] != __end2 && !__op._M_comp((__offset[0] - 1), __offset[1]) && !__op._M_comp(__offset[1], (__offset[0] - 1))) { // Avoid split between globally equal elements: move one to // front in first sequence. --__offset[0]; } _IteratorPair __block_end = __block_begins[__iam + 1] = _IteratorPair(__offset[0], __offset[1]); // Make sure all threads have their block_begin result written out. # pragma omp barrier _IteratorPair __block_begin = __block_begins[__iam]; // Begin working for the first block, while the others except // the last start to count. if (__iam == 0) { // The first thread can copy already. __lengths[ __iam ] = __op._M_invoke(__block_begin.first, __block_end.first, __block_begin.second, __block_end.second, __result) - __result; } else { __lengths[ __iam ] = __op.__count(__block_begin.first, __block_end.first, __block_begin.second, __block_end.second); } // Make sure everyone wrote their lengths. # pragma omp barrier _OutputIterator __r = __result; if (__iam == 0) { // Do the last block. for (_ThreadIndex __i = 0; __i < __num_threads; ++__i) __r += __lengths[__i]; __block_begin = __block_begins[__num_threads]; // Return the result iterator of the last block. __return_value = __op._M_invoke(__block_begin.first, __end1, __block_begin.second, __end2, __r); } else { for (_ThreadIndex __i = 0; __i < __iam; ++__i) __r += __lengths[ __i ]; // Reset begins for copy pass. __op._M_invoke(__block_begin.first, __block_end.first, __block_begin.second, __block_end.second, __r); } } return __return_value; } template<typename _IIter, typename _OutputIterator, typename _Compare> inline _OutputIterator __parallel_set_union(_IIter __begin1, _IIter __end1, _IIter __begin2, _IIter __end2, _OutputIterator __result, _Compare __comp) { return __parallel_set_operation(__begin1, __end1, __begin2, __end2, __result, __union_func< _IIter, _OutputIterator, _Compare>(__comp)); } template<typename _IIter, typename _OutputIterator, typename _Compare> inline _OutputIterator __parallel_set_intersection(_IIter __begin1, _IIter __end1, _IIter __begin2, _IIter __end2, _OutputIterator __result, _Compare __comp) { return __parallel_set_operation(__begin1, __end1, __begin2, __end2, __result, __intersection_func<_IIter, _OutputIterator, _Compare>(__comp)); } template<typename _IIter, typename _OutputIterator, typename _Compare> inline _OutputIterator __parallel_set_difference(_IIter __begin1, _IIter __end1, _IIter __begin2, _IIter __end2, _OutputIterator __result, _Compare __comp) { return __parallel_set_operation(__begin1, __end1, __begin2, __end2, __result, __difference_func<_IIter, _OutputIterator, _Compare>(__comp)); } template<typename _IIter, typename _OutputIterator, typename _Compare> inline _OutputIterator __parallel_set_symmetric_difference(_IIter __begin1, _IIter __end1, _IIter __begin2, _IIter __end2, _OutputIterator __result, _Compare __comp) { return __parallel_set_operation(__begin1, __end1, __begin2, __end2, __result, __symmetric_difference_func<_IIter, _OutputIterator, _Compare>(__comp)); } } #endif /* _GLIBCXX_PARALLEL_SET_OPERATIONS_H */	14.25 KB	2025-09-15 15:41
📄 settings.h // -- C++ -- // Copyright (C) 2007-2021 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/settings.h * @brief Runtime settings and tuning parameters, heuristics to decide * whether to use parallelized algorithms. * * This file is a GNU parallel extension to the Standard C++ Library. * * @section parallelization_decision Deciding whether to run an algorithm in parallel. * * There are several ways the user can switch on and off the parallel * execution of an algorithm, both at compile- and run-time. * * Only sequential execution can be forced at compile-time. This * reduces code size and protects code parts that have * non-thread-safe side effects. * * Ultimately, forcing parallel execution at compile-time makes * sense. Often, the sequential algorithm implementation is used as * a subroutine, so no reduction in code size can be achieved. Also, * the machine the program is run on might have only one processor * core, so to avoid overhead, the algorithm is executed * sequentially. * * To force sequential execution of an algorithm ultimately at * compile-time, the user must add the tag * gnu_parallel::sequential_tag() to the end of the parameter list, * e. g. * * \code * std::sort(__v.begin(), __v.end(), __gnu_parallel::sequential_tag()); * \endcode * * This is compatible with all overloaded algorithm variants. No * additional code will be instantiated, at all. The same holds for * most algorithm calls with iterators not providing random access. * * If the algorithm call is not forced to be executed sequentially * at compile-time, the decision is made at run-time. * The global variable __gnu_parallel::_Settings::algorithm_strategy * is checked. It is a tristate variable corresponding to: * - a. force_sequential, meaning the sequential algorithm is executed. * - b. force_parallel, meaning the parallel algorithm is executed. * - c. heuristic * * For heuristic, the parallel algorithm implementation is called * only if the input size is sufficiently large. For most * algorithms, the input size is the (combined) length of the input * sequence(__s). The threshold can be set by the user, individually * for each algorithm. The according variables are called * gnu_parallel::_Settings::[algorithm]_minimal_n . * * For some of the algorithms, there are even more tuning options, * e. g. the ability to choose from multiple algorithm variants. See * below for details. / // Written by Johannes Singler and Felix Putze. #ifndef _GLIBCXX_PARALLEL_SETTINGS_H #define _GLIBCXX_PARALLEL_SETTINGS_H 1 #include <parallel/types.h> /* * @brief Determine at compile(?)-time if the parallel variant of an * algorithm should be called. * @param __c A condition that is convertible to bool that is overruled by * __gnu_parallel::_Settings::algorithm_strategy. Usually a decision * based on the input size. / #define _GLIBCXX_PARALLEL_CONDITION(__c) \ (__gnu_parallel::_Settings::get().algorithm_strategy \ != __gnu_parallel::force_sequential \ && ((__gnu_parallel::__get_max_threads() > 1 && (__c)) \ \|\| __gnu_parallel::_Settings::get().algorithm_strategy \ == __gnu_parallel::force_parallel)) / inline bool parallel_condition(bool __c) { bool ret = false; const _Settings& __s = _Settings::get(); if (__s.algorithm_strategy != force_seqential) { if (__s.algorithm_strategy == force_parallel) ret = true; else ret = __get_max_threads() > 1 && __c; } return ret; } / namespace __gnu_parallel { /// class _Settings /// Run-time settings for the parallel mode including all tunable parameters. struct _Settings { _AlgorithmStrategy algorithm_strategy; _SortAlgorithm sort_algorithm; _PartialSumAlgorithm partial_sum_algorithm; _MultiwayMergeAlgorithm multiway_merge_algorithm; _FindAlgorithm find_algorithm; _SplittingAlgorithm sort_splitting; _SplittingAlgorithm merge_splitting; _SplittingAlgorithm multiway_merge_splitting; // Per-algorithm settings. /// Minimal input size for accumulate. _SequenceIndex accumulate_minimal_n; /// Minimal input size for adjacent_difference. unsigned int adjacent_difference_minimal_n; /// Minimal input size for count and count_if. _SequenceIndex count_minimal_n; /// Minimal input size for fill. _SequenceIndex fill_minimal_n; /// Block size increase factor for find. double find_increasing_factor; /// Initial block size for find. _SequenceIndex find_initial_block_size; /// Maximal block size for find. _SequenceIndex find_maximum_block_size; /// Start with looking for this many elements sequentially, for find. _SequenceIndex find_sequential_search_size; /// Minimal input size for for_each. _SequenceIndex for_each_minimal_n; /// Minimal input size for generate. _SequenceIndex generate_minimal_n; /// Minimal input size for max_element. _SequenceIndex max_element_minimal_n; /// Minimal input size for merge. _SequenceIndex merge_minimal_n; /// Oversampling factor for merge. unsigned int merge_oversampling; /// Minimal input size for min_element. _SequenceIndex min_element_minimal_n; /// Minimal input size for multiway_merge. _SequenceIndex multiway_merge_minimal_n; /// Oversampling factor for multiway_merge. int multiway_merge_minimal_k; /// Oversampling factor for multiway_merge. unsigned int multiway_merge_oversampling; /// Minimal input size for nth_element. _SequenceIndex nth_element_minimal_n; /// Chunk size for partition. _SequenceIndex partition_chunk_size; /// Chunk size for partition, relative to input size. If > 0.0, /// this value overrides partition_chunk_size. double partition_chunk_share; /// Minimal input size for partition. _SequenceIndex partition_minimal_n; /// Minimal input size for partial_sort. _SequenceIndex partial_sort_minimal_n; /// Ratio for partial_sum. Assume "sum and write result" to be /// this factor slower than just "sum". float partial_sum_dilation; /// Minimal input size for partial_sum. unsigned int partial_sum_minimal_n; /// Minimal input size for random_shuffle. unsigned int random_shuffle_minimal_n; /// Minimal input size for replace and replace_if. _SequenceIndex replace_minimal_n; /// Minimal input size for set_difference. _SequenceIndex set_difference_minimal_n; /// Minimal input size for set_intersection. _SequenceIndex set_intersection_minimal_n; /// Minimal input size for set_symmetric_difference. _SequenceIndex set_symmetric_difference_minimal_n; /// Minimal input size for set_union. _SequenceIndex set_union_minimal_n; /// Minimal input size for parallel sorting. _SequenceIndex sort_minimal_n; /// Oversampling factor for parallel std::sort (MWMS). unsigned int sort_mwms_oversampling; /// Such many samples to take to find a good pivot (quicksort). unsigned int sort_qs_num_samples_preset; /// Maximal subsequence __length to switch to unbalanced __base case. /// Applies to std::sort with dynamically load-balanced quicksort. _SequenceIndex sort_qsb_base_case_maximal_n; /// Minimal input size for parallel std::transform. _SequenceIndex transform_minimal_n; /// Minimal input size for unique_copy. _SequenceIndex unique_copy_minimal_n; _SequenceIndex workstealing_chunk_size; // Hardware dependent tuning parameters. /// size of the L1 cache in bytes (underestimation). unsigned long long L1_cache_size; /// size of the L2 cache in bytes (underestimation). unsigned long long L2_cache_size; /// size of the Translation Lookaside Buffer (underestimation). unsigned int TLB_size; /// Overestimation of cache line size. Used to avoid false /// sharing, i.e. elements of different threads are at least this /// amount apart. unsigned int cache_line_size; // Statistics. /// The number of stolen ranges in load-balanced quicksort. _SequenceIndex qsb_steals; /// Minimal input size for search and search_n. _SequenceIndex search_minimal_n; /// Block size scale-down factor with respect to current position. float find_scale_factor; /// Get the global settings. _GLIBCXX_CONST static const _Settings& get() throw(); /// Set the global settings. static void set(_Settings&) throw(); explicit _Settings() : algorithm_strategy(heuristic), sort_algorithm(MWMS), partial_sum_algorithm(LINEAR), multiway_merge_algorithm(LOSER_TREE), find_algorithm(CONSTANT_SIZE_BLOCKS), sort_splitting(EXACT), merge_splitting(EXACT), multiway_merge_splitting(EXACT), accumulate_minimal_n(1000), adjacent_difference_minimal_n(1000), count_minimal_n(1000), fill_minimal_n(1000), find_increasing_factor(2.0), find_initial_block_size(256), find_maximum_block_size(8192), find_sequential_search_size(256), for_each_minimal_n(1000), generate_minimal_n(1000), max_element_minimal_n(1000), merge_minimal_n(1000), merge_oversampling(10), min_element_minimal_n(1000), multiway_merge_minimal_n(1000), multiway_merge_minimal_k(2), multiway_merge_oversampling(10), nth_element_minimal_n(1000), partition_chunk_size(1000), partition_chunk_share(0.0), partition_minimal_n(1000), partial_sort_minimal_n(1000), partial_sum_dilation(1.0f), partial_sum_minimal_n(1000), random_shuffle_minimal_n(1000), replace_minimal_n(1000), set_difference_minimal_n(1000), set_intersection_minimal_n(1000), set_symmetric_difference_minimal_n(1000), set_union_minimal_n(1000), sort_minimal_n(1000), sort_mwms_oversampling(10), sort_qs_num_samples_preset(100), sort_qsb_base_case_maximal_n(100), transform_minimal_n(1000), unique_copy_minimal_n(10000), workstealing_chunk_size(100), L1_cache_size(16 << 10), L2_cache_size(256 << 10), TLB_size(128), cache_line_size(64), qsb_steals(0), search_minimal_n(1000), find_scale_factor(0.01f) { } }; } #endif / _GLIBCXX_PARALLEL_SETTINGS_H */	12.17 KB	2025-09-15 15:41
📄 sort.h // -- C++ -- // Copyright (C) 2007-2021 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/sort.h * @brief Parallel sorting algorithm switch. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler. #ifndef _GLIBCXX_PARALLEL_SORT_H #define _GLIBCXX_PARALLEL_SORT_H 1 #include <parallel/basic_iterator.h> #include <parallel/features.h> #include <parallel/parallel.h> #if _GLIBCXX_PARALLEL_ASSERTIONS #include <parallel/checkers.h> #endif #if _GLIBCXX_MERGESORT #include <parallel/multiway_mergesort.h> #endif #if _GLIBCXX_QUICKSORT #include <parallel/quicksort.h> #endif #if _GLIBCXX_BAL_QUICKSORT #include <parallel/balanced_quicksort.h> #endif namespace __gnu_parallel { //prototype template<bool __stable, typename _RAIter, typename _Compare, typename _Parallelism> void __parallel_sort(_RAIter __begin, _RAIter __end, _Compare __comp, _Parallelism __parallelism); /* * @brief Choose multiway mergesort, splitting variant at run-time, * for parallel sorting. * @param __begin Begin iterator of input sequence. * @param __end End iterator of input sequence. * @param __comp Comparator. * @tparam __stable Sort stable. * @callgraph / template<bool __stable, typename _RAIter, typename _Compare> inline void __parallel_sort(_RAIter __begin, _RAIter __end, _Compare __comp, multiway_mergesort_tag __parallelism) { _GLIBCXX_CALL(__end - __begin) if(_Settings::get().sort_splitting == EXACT) parallel_sort_mwms<__stable, true> (__begin, __end, __comp, __parallelism.__get_num_threads()); else parallel_sort_mwms<__stable, false> (__begin, __end, __comp, __parallelism.__get_num_threads()); } /* * @brief Choose multiway mergesort with exact splitting, * for parallel sorting. * @param __begin Begin iterator of input sequence. * @param __end End iterator of input sequence. * @param __comp Comparator. * @tparam __stable Sort stable. * @callgraph / template<bool __stable, typename _RAIter, typename _Compare> inline void __parallel_sort(_RAIter __begin, _RAIter __end, _Compare __comp, multiway_mergesort_exact_tag __parallelism) { _GLIBCXX_CALL(__end - __begin) parallel_sort_mwms<__stable, true> (__begin, __end, __comp, __parallelism.__get_num_threads()); } /* * @brief Choose multiway mergesort with splitting by sampling, * for parallel sorting. * @param __begin Begin iterator of input sequence. * @param __end End iterator of input sequence. * @param __comp Comparator. * @tparam __stable Sort stable. * @callgraph / template<bool __stable, typename _RAIter, typename _Compare> inline void __parallel_sort(_RAIter __begin, _RAIter __end, _Compare __comp, multiway_mergesort_sampling_tag __parallelism) { _GLIBCXX_CALL(__end - __begin) parallel_sort_mwms<__stable, false> (__begin, __end, __comp, __parallelism.__get_num_threads()); } /* * @brief Choose quicksort for parallel sorting. * @param __begin Begin iterator of input sequence. * @param __end End iterator of input sequence. * @param __comp Comparator. * @tparam __stable Sort stable. * @callgraph / template<bool __stable, typename _RAIter, typename _Compare> inline void __parallel_sort(_RAIter __begin, _RAIter __end, _Compare __comp, quicksort_tag __parallelism) { _GLIBCXX_CALL(__end - __begin) _GLIBCXX_PARALLEL_ASSERT(__stable == false); __parallel_sort_qs(__begin, __end, __comp, __parallelism.__get_num_threads()); } /* * @brief Choose balanced quicksort for parallel sorting. * @param __begin Begin iterator of input sequence. * @param __end End iterator of input sequence. * @param __comp Comparator. * @tparam __stable Sort stable. * @callgraph / template<bool __stable, typename _RAIter, typename _Compare> inline void __parallel_sort(_RAIter __begin, _RAIter __end, _Compare __comp, balanced_quicksort_tag __parallelism) { _GLIBCXX_CALL(__end - __begin) _GLIBCXX_PARALLEL_ASSERT(__stable == false); __parallel_sort_qsb(__begin, __end, __comp, __parallelism.__get_num_threads()); } /* * @brief Choose multiway mergesort with exact splitting, * for parallel sorting. * @param __begin Begin iterator of input sequence. * @param __end End iterator of input sequence. * @param __comp Comparator. * @tparam __stable Sort stable. * @callgraph / template<bool __stable, typename _RAIter, typename _Compare> inline void __parallel_sort(_RAIter __begin, _RAIter __end, _Compare __comp, default_parallel_tag __parallelism) { _GLIBCXX_CALL(__end - __begin) __parallel_sort<__stable> (__begin, __end, __comp, multiway_mergesort_exact_tag(__parallelism.__get_num_threads())); } /* * @brief Choose a parallel sorting algorithm. * @param __begin Begin iterator of input sequence. * @param __end End iterator of input sequence. * @param __comp Comparator. * @tparam __stable Sort stable. * @callgraph / template<bool __stable, typename _RAIter, typename _Compare> inline void __parallel_sort(_RAIter __begin, _RAIter __end, _Compare __comp, parallel_tag __parallelism) { _GLIBCXX_CALL(__end - __begin) typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; if (false) ; #if _GLIBCXX_MERGESORT else if (__stable \|\| _Settings::get().sort_algorithm == MWMS) { if(_Settings::get().sort_splitting == EXACT) parallel_sort_mwms<__stable, true> (__begin, __end, __comp, __parallelism.__get_num_threads()); else parallel_sort_mwms<false, false> (__begin, __end, __comp, __parallelism.__get_num_threads()); } #endif #if _GLIBCXX_QUICKSORT else if (_Settings::get().sort_algorithm == QS) __parallel_sort_qs(__begin, __end, __comp, __parallelism.__get_num_threads()); #endif #if _GLIBCXX_BAL_QUICKSORT else if (_Settings::get().sort_algorithm == QS_BALANCED) __parallel_sort_qsb(__begin, __end, __comp, __parallelism.__get_num_threads()); #endif else __gnu_sequential::sort(__begin, __end, __comp); } } // end namespace __gnu_parallel #endif / _GLIBCXX_PARALLEL_SORT_H */	7.53 KB	2025-09-15 15:41
📄 tags.h // -- C++ -- // Copyright (C) 2007-2021 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 */	5.84 KB	2025-09-15 15:41
📄 types.h // -- C++ -- // Copyright (C) 2007-2021 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/types.h * @brief Basic types and typedefs. * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Johannes Singler and Felix Putze. #ifndef _GLIBCXX_PARALLEL_TYPES_H #define _GLIBCXX_PARALLEL_TYPES_H 1 #include <cstdlib> #include <limits> #include <tr1/cstdint> namespace __gnu_parallel { // Enumerated types. /// Run-time equivalents for the compile-time tags. enum _Parallelism { /// Not parallel. sequential, /// Parallel unbalanced (equal-sized chunks). parallel_unbalanced, /// Parallel balanced (work-stealing). parallel_balanced, /// Parallel with OpenMP dynamic load-balancing. parallel_omp_loop, /// Parallel with OpenMP static load-balancing. parallel_omp_loop_static, /// Parallel with OpenMP taskqueue construct. parallel_taskqueue }; /// Strategies for run-time algorithm selection: // force_sequential, force_parallel, heuristic. enum _AlgorithmStrategy { heuristic, force_sequential, force_parallel }; /// Sorting algorithms: // multi-way mergesort, quicksort, load-balanced quicksort. enum _SortAlgorithm { MWMS, QS, QS_BALANCED }; /// Merging algorithms: // bubblesort-alike, loser-tree variants, enum __sentinel. enum _MultiwayMergeAlgorithm { LOSER_TREE }; /// Partial sum algorithms: recursive, linear. enum _PartialSumAlgorithm { RECURSIVE, LINEAR }; /// Sorting/merging algorithms: sampling, __exact. enum _SplittingAlgorithm { SAMPLING, EXACT }; /// Find algorithms: // growing blocks, equal-sized blocks, equal splitting. enum _FindAlgorithm { GROWING_BLOCKS, CONSTANT_SIZE_BLOCKS, EQUAL_SPLIT }; /* * @brief Unsigned integer to index __elements. * The total number of elements for each algorithm must fit into this type. / typedef uint64_t _SequenceIndex; /* * @brief Unsigned integer to index a thread number. * The maximum thread number (for each processor) must fit into this type. / typedef uint16_t _ThreadIndex; // XXX atomics interface? /// Longest compare-and-swappable integer type on this platform. typedef int64_t _CASable; /// Number of bits of _CASable. static const int _CASable_bits = std::numeric_limits<_CASable>::digits; /// ::_CASable with the right half of bits set to 1. static const _CASable _CASable_mask = ((_CASable(1) << (_CASable_bits / 2)) - 1); } #endif / _GLIBCXX_PARALLEL_TYPES_H */	3.63 KB	2025-09-15 15:41
📄 unique_copy.h // -- C++ -- // Copyright (C) 2007-2021 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/unique_copy.h * @brief Parallel implementations of std::unique_copy(). * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Robert Geisberger and Robin Dapp. #ifndef _GLIBCXX_PARALLEL_UNIQUE_COPY_H #define _GLIBCXX_PARALLEL_UNIQUE_COPY_H 1 #include <parallel/parallel.h> #include <parallel/multiseq_selection.h> namespace __gnu_parallel { /* @brief Parallel std::unique_copy(), w/__o explicit equality predicate. * @param __first Begin iterator of input sequence. * @param __last End iterator of input sequence. * @param __result Begin iterator of result __sequence. * @param __binary_pred Equality predicate. * @return End iterator of result __sequence. / template<typename _IIter, class _OutputIterator, class _BinaryPredicate> _OutputIterator __parallel_unique_copy(_IIter __first, _IIter __last, _OutputIterator __result, _BinaryPredicate __binary_pred) { _GLIBCXX_CALL(__last - __first) typedef std::iterator_traits<_IIter> _TraitsType; typedef typename _TraitsType::value_type _ValueType; typedef typename _TraitsType::difference_type _DifferenceType; _DifferenceType __size = __last - __first; if (__size == 0) return __result; // Let the first thread process two parts. _DifferenceType __counter; _DifferenceType __borders; _ThreadIndex __num_threads = __get_max_threads(); // First part contains at least one element. # pragma omp parallel num_threads(__num_threads) { # pragma omp single { __num_threads = omp_get_num_threads(); __borders = new _DifferenceType[__num_threads + 2]; __equally_split(__size, __num_threads + 1, __borders); __counter = new _DifferenceType[__num_threads + 1]; } _ThreadIndex __iam = omp_get_thread_num(); _DifferenceType __begin, __end; // Check for length without duplicates // Needed for position in output _DifferenceType __i = 0; _OutputIterator __out = __result; if (__iam == 0) { __begin = __borders[0] + 1; // == 1 __end = __borders[__iam + 1]; ++__i; __out++ = __first; for (_IIter __iter = __first + __begin; __iter < __first + __end; ++__iter) { if (!__binary_pred(__iter, (__iter - 1))) { ++__i; __out++ = __iter; } } } else { __begin = __borders[__iam]; //one part __end = __borders[__iam + 1]; for (_IIter __iter = __first + __begin; __iter < __first + __end; ++__iter) { if (!__binary_pred(__iter, (__iter - 1))) ++__i; } } __counter[__iam] = __i; // Last part still untouched. _DifferenceType __begin_output; # pragma omp barrier // Store result in output on calculated positions. __begin_output = 0; if (__iam == 0) { for (_ThreadIndex __t = 0; __t < __num_threads; ++__t) __begin_output += __counter[__t]; __i = 0; _OutputIterator __iter_out = __result + __begin_output; __begin = __borders[__num_threads]; __end = __size; for (_IIter __iter = __first + __begin; __iter < __first + __end; ++__iter) { if (__iter == __first \|\| !__binary_pred(__iter, (__iter - 1))) { ++__i; __iter_out++ = __iter; } } __counter[__num_threads] = __i; } else { for (_ThreadIndex __t = 0; __t < __iam; __t++) __begin_output += __counter[__t]; _OutputIterator __iter_out = __result + __begin_output; for (_IIter __iter = __first + __begin; __iter < __first + __end; ++__iter) { if (!__binary_pred(__iter, (__iter - 1))) __iter_out++ = __iter; } } } _DifferenceType __end_output = 0; for (_ThreadIndex __t = 0; __t < __num_threads + 1; __t++) __end_output += __counter[__t]; delete[] __borders; return __result + __end_output; } /* @brief Parallel std::unique_copy(), without explicit equality predicate * @param __first Begin iterator of input sequence. * @param __last End iterator of input sequence. * @param __result Begin iterator of result __sequence. * @return End iterator of result __sequence. / template<typename _IIter, class _OutputIterator> inline _OutputIterator __parallel_unique_copy(_IIter __first, _IIter __last, _OutputIterator __result) { typedef typename std::iterator_traits<_IIter>::value_type _ValueType; return __parallel_unique_copy(__first, __last, __result, std::equal_to<_ValueType>()); } }//namespace __gnu_parallel #endif / _GLIBCXX_PARALLEL_UNIQUE_COPY_H */	6.02 KB	2025-09-15 15:41
📄 workstealing.h // -- C++ -- // Copyright (C) 2007-2021 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/workstealing.h * @brief Parallelization of embarrassingly parallel execution by * means of work-stealing. * * Work stealing is described in * * R. D. Blumofe and C. E. Leiserson. * Scheduling multithreaded computations by work stealing. * Journal of the ACM, 46(5):720-748, 1999. * * This file is a GNU parallel extension to the Standard C++ Library. / // Written by Felix Putze. #ifndef _GLIBCXX_PARALLEL_WORKSTEALING_H #define _GLIBCXX_PARALLEL_WORKSTEALING_H 1 #include <parallel/parallel.h> #include <parallel/random_number.h> #include <parallel/compatibility.h> namespace __gnu_parallel { #define _GLIBCXX_JOB_VOLATILE volatile /* @brief One __job for a certain thread. / template<typename _DifferenceTp> struct _Job { typedef _DifferenceTp _DifferenceType; /* @brief First element. * * Changed by owning and stealing thread. By stealing thread, * always incremented. / _GLIBCXX_JOB_VOLATILE _DifferenceType _M_first; /* @brief Last element. * * Changed by owning thread only. / _GLIBCXX_JOB_VOLATILE _DifferenceType _M_last; /* @brief Number of elements, i.e. @c _M_last-_M_first+1. * * Changed by owning thread only. / _GLIBCXX_JOB_VOLATILE _DifferenceType _M_load; }; /* @brief Work stealing algorithm for random access iterators. * * Uses O(1) additional memory. Synchronization at job lists is * done with atomic operations. * @param __begin Begin iterator of element sequence. * @param __end End iterator of element sequence. * @param __op User-supplied functor (comparator, predicate, adding * functor, ...). * @param __f Functor to @a process an element with __op (depends on * desired functionality, e. g. for std::for_each(), ...). * @param __r Functor to @a add a single __result to the already * processed elements (depends on functionality). * @param __base Base value for reduction. * @param __output Pointer to position where final result is written to * @param __bound Maximum number of elements processed (e. g. for * std::count_n()). * @return User-supplied functor (that may contain a part of the result). / template<typename _RAIter, typename _Op, typename _Fu, typename _Red, typename _Result> _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) { _GLIBCXX_CALL(__end - __begin) typedef std::iterator_traits<_RAIter> _TraitsType; typedef typename _TraitsType::difference_type _DifferenceType; const _Settings& __s = _Settings::get(); _DifferenceType __chunk_size = static_cast<_DifferenceType>(__s.workstealing_chunk_size); // How many jobs? _DifferenceType __length = (__bound < 0) ? (__end - __begin) : __bound; // To avoid false sharing in a cache line. const int __stride = (__s.cache_line_size 10 / sizeof(_Job<_DifferenceType>) + 1); // Total number of threads currently working. _ThreadIndex __busy = 0; _Job<_DifferenceType> __job; omp_lock_t __output_lock; omp_init_lock(&__output_lock); // Write base value to output. __output = __base; // No more threads than jobs, at least one thread. _ThreadIndex __num_threads = __gnu_parallel::max<_ThreadIndex> (1, __gnu_parallel::min<_DifferenceType>(__length, __get_max_threads())); # pragma omp parallel shared(__busy) num_threads(__num_threads) { # pragma omp single { __num_threads = omp_get_num_threads(); // Create job description array. __job = new _Job<_DifferenceType>[__num_threads __stride]; } // Initialization phase. // Flags for every thread if it is doing productive work. bool __iam_working = false; // Thread id. _ThreadIndex __iam = omp_get_thread_num(); // This job. _Job<_DifferenceType>& __my_job = __job[__iam * __stride]; // Random number (for work stealing). _ThreadIndex __victim; // Local value for reduction. _Result __result = _Result(); // Number of elements to steal in one attempt. _DifferenceType __steal; // Every thread has its own random number generator // (modulo __num_threads). _RandomNumber __rand_gen(__iam, __num_threads); // This thread is currently working. # pragma omp atomic ++__busy; __iam_working = true; // How many jobs per thread? last thread gets the rest. __my_job._M_first = static_cast<_DifferenceType> (__iam * (__length / __num_threads)); __my_job._M_last = (__iam == (__num_threads - 1) ? (__length - 1) : ((__iam + 1) * (__length / __num_threads) - 1)); __my_job._M_load = __my_job._M_last - __my_job._M_first + 1; // Init result with _M_first value (to have a base value for reduction) if (__my_job._M_first <= __my_job._M_last) { // Cannot use volatile variable directly. _DifferenceType __my_first = __my_job._M_first; __result = __f(__op, __begin + __my_first); ++__my_job._M_first; --__my_job._M_load; } _RAIter __current; # pragma omp barrier // Actual work phase // Work on own or stolen current start while (__busy > 0) { // Work until no productive thread left. # pragma omp flush(__busy) // Thread has own work to do while (__my_job._M_first <= __my_job._M_last) { // fetch-and-add call // Reserve current job block (size __chunk_size) in my queue. _DifferenceType __current_job = __fetch_and_add<_DifferenceType>(&(__my_job._M_first), __chunk_size); // Update _M_load, to make the three values consistent, // _M_first might have been changed in the meantime __my_job._M_load = __my_job._M_last - __my_job._M_first + 1; for (_DifferenceType __job_counter = 0; __job_counter < __chunk_size && __current_job <= __my_job._M_last; ++__job_counter) { // Yes: process it! __current = __begin + __current_job; ++__current_job; // Do actual work. __result = __r(__result, __f(__op, __current)); } # pragma omp flush(__busy) } // After reaching this point, a thread's __job list is empty. if (__iam_working) { // This thread no longer has work. # pragma omp atomic --__busy; __iam_working = false; } _DifferenceType __supposed_first, __supposed_last, __supposed_load; do { // Find random nonempty deque (not own), do consistency check. __yield(); # pragma omp flush(__busy) __victim = __rand_gen(); __supposed_first = __job[__victim * __stride]._M_first; __supposed_last = __job[__victim * __stride]._M_last; __supposed_load = __job[__victim * __stride]._M_load; } while (__busy > 0 && ((__supposed_load <= 0) \|\| ((__supposed_first + __supposed_load - 1) != __supposed_last))); if (__busy == 0) break; if (__supposed_load > 0) { // Has work and work to do. // Number of elements to steal (at least one). __steal = (__supposed_load < 2) ? 1 : __supposed_load / 2; // Push __victim's current start forward. _DifferenceType __stolen_first = __fetch_and_add<_DifferenceType> (&(__job[__victim * __stride]._M_first), __steal); _DifferenceType __stolen_try = (__stolen_first + __steal - _DifferenceType(1)); __my_job._M_first = __stolen_first; __my_job._M_last = __gnu_parallel::min(__stolen_try, __supposed_last); __my_job._M_load = __my_job._M_last - __my_job._M_first + 1; // Has potential work again. # pragma omp atomic ++__busy; __iam_working = true; # pragma omp flush(__busy) } # pragma omp flush(__busy) } // end while __busy > 0 // Add accumulated result to output. omp_set_lock(&__output_lock); __output = __r(__output, __result); omp_unset_lock(&__output_lock); } delete[] __job; // Points to last element processed (needed as return value for // some algorithms like transform) __f._M_finish_iterator = __begin + __length; omp_destroy_lock(&__output_lock); return __op; } } // end namespace #endif /* _GLIBCXX_PARALLEL_WORKSTEALING_H */	9.38 KB	2025-09-15 15:41

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