1//===----------------------------------------------------------------------===// 2// 3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4// See https://llvm.org/LICENSE.txt for license information. 5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6// 7//===----------------------------------------------------------------------===// 8 9#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_CPU_BACKNEDS_FOR_EACH_H 10#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_CPU_BACKNEDS_FOR_EACH_H 11 12#include <__algorithm/for_each.h> 13#include <__algorithm/pstl_backends/cpu_backends/backend.h> 14#include <__config> 15#include <__iterator/concepts.h> 16#include <__type_traits/is_execution_policy.h> 17#include <__utility/empty.h> 18#include <optional> 19 20#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 21# pragma GCC system_header 22#endif 23 24#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17 25 26_LIBCPP_BEGIN_NAMESPACE_STD 27 28template <class _Iterator, class _DifferenceType, class _Function> 29_LIBCPP_HIDE_FROM_ABI _Iterator __simd_walk(_Iterator __first, _DifferenceType __n, _Function __f) noexcept { 30 _PSTL_PRAGMA_SIMD 31 for (_DifferenceType __i = 0; __i < __n; ++__i) 32 __f(__first[__i]); 33 34 return __first + __n; 35} 36 37template <class _ExecutionPolicy, class _ForwardIterator, class _Functor> 38_LIBCPP_HIDE_FROM_ABI optional<__empty> 39__pstl_for_each(__cpu_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Functor __func) { 40 if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> && 41 __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) { 42 return std::__par_backend::__parallel_for( 43 __first, __last, [__func](_ForwardIterator __brick_first, _ForwardIterator __brick_last) { 44 [[maybe_unused]] auto __res = std::__pstl_for_each<__remove_parallel_policy_t<_ExecutionPolicy>>( 45 __cpu_backend_tag{}, __brick_first, __brick_last, __func); 46 _LIBCPP_ASSERT_INTERNAL(__res, "unseq/seq should never try to allocate!"); 47 }); 48 } else if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> && 49 __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) { 50 std::__simd_walk(__first, __last - __first, __func); 51 return __empty{}; 52 } else { 53 std::for_each(__first, __last, __func); 54 return __empty{}; 55 } 56} 57 58_LIBCPP_END_NAMESPACE_STD 59 60#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17 61 62#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_CPU_BACKNEDS_FOR_EACH_H 63