| // -*- C++ -*- |
| //===----------------------------------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef _PSTL_EXECUTION_IMPL_H |
| #define _PSTL_EXECUTION_IMPL_H |
| |
| #include <iterator> |
| #include <type_traits> |
| |
| #include "pstl_config.h" |
| #include "execution_defs.h" |
| |
| _PSTL_HIDE_FROM_ABI_PUSH |
| |
| namespace __pstl |
| { |
| namespace __internal |
| { |
| |
| template <typename _IteratorTag, typename... _IteratorTypes> |
| using __are_iterators_of = std::conjunction< |
| std::is_base_of<_IteratorTag, typename std::iterator_traits<std::decay_t<_IteratorTypes>>::iterator_category>...>; |
| |
| template <typename... _IteratorTypes> |
| using __are_random_access_iterators = __are_iterators_of<std::random_access_iterator_tag, _IteratorTypes...>; |
| |
| struct __serial_backend_tag |
| { |
| }; |
| struct __tbb_backend_tag |
| { |
| }; |
| struct __openmp_backend_tag |
| { |
| }; |
| |
| #if defined(_PSTL_PAR_BACKEND_TBB) |
| using __par_backend_tag = __tbb_backend_tag; |
| #elif defined(_PSTL_PAR_BACKEND_OPENMP) |
| using __par_backend_tag = __openmp_backend_tag; |
| #elif defined(_PSTL_PAR_BACKEND_SERIAL) |
| using __par_backend_tag = __serial_backend_tag; |
| #else |
| # error "A parallel backend must be specified"; |
| #endif |
| |
| template <class _IsVector> |
| struct __serial_tag |
| { |
| using __is_vector = _IsVector; |
| }; |
| |
| template <class _IsVector> |
| struct __parallel_tag |
| { |
| using __is_vector = _IsVector; |
| // backend tag can be change depending on |
| // TBB availability in the environment |
| using __backend_tag = __par_backend_tag; |
| }; |
| |
| template <class _IsVector, class... _IteratorTypes> |
| using __tag_type = typename std::conditional<__internal::__are_random_access_iterators<_IteratorTypes...>::value, |
| __parallel_tag<_IsVector>, __serial_tag<_IsVector>>::type; |
| |
| template <class... _IteratorTypes> |
| __serial_tag</*_IsVector = */ std::false_type> |
| __select_backend(__pstl::execution::sequenced_policy, _IteratorTypes&&...) |
| { |
| return {}; |
| } |
| |
| template <class... _IteratorTypes> |
| __serial_tag<__internal::__are_random_access_iterators<_IteratorTypes...>> |
| __select_backend(__pstl::execution::unsequenced_policy, _IteratorTypes&&...) |
| { |
| return {}; |
| } |
| |
| template <class... _IteratorTypes> |
| __tag_type</*_IsVector = */ std::false_type, _IteratorTypes...> |
| __select_backend(__pstl::execution::parallel_policy, _IteratorTypes&&...) |
| { |
| return {}; |
| } |
| |
| template <class... _IteratorTypes> |
| __tag_type<__internal::__are_random_access_iterators<_IteratorTypes...>, _IteratorTypes...> |
| __select_backend(__pstl::execution::parallel_unsequenced_policy, _IteratorTypes&&...) |
| { |
| return {}; |
| } |
| |
| } // namespace __internal |
| } // namespace __pstl |
| |
| _PSTL_HIDE_FROM_ABI_POP |
| |
| #endif /* _PSTL_EXECUTION_IMPL_H */ |