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// -*- C++ -*- // Copyright (C) 2007-2018 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) __glibcxx_assert_impl(_Condition) #else #define _GLIBCXX_PARALLEL_ASSERT(_Condition) #endif } //namespace __gnu_parallel #endif /* _GLIBCXX_PARALLEL_BASE_H */
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