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
28 template <class _Iterator, class _DifferenceType, class _Function>
__simd_walk(_Iterator __first,_DifferenceType __n,_Function __f)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
37 template <class _ExecutionPolicy, class _ForwardIterator, class _Functor>
38 _LIBCPP_HIDE_FROM_ABI optional<__empty>
__pstl_for_each(__cpu_backend_tag,_ForwardIterator __first,_ForwardIterator __last,_Functor __func)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