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_FOR_EACH_H
10 #define _LIBCPP___ALGORITHM_PSTL_FOR_EACH_H
11 
12 #include <__algorithm/for_each.h>
13 #include <__algorithm/for_each_n.h>
14 #include <__algorithm/pstl_backend.h>
15 #include <__algorithm/pstl_frontend_dispatch.h>
16 #include <__config>
17 #include <__iterator/concepts.h>
18 #include <__iterator/cpp17_iterator_concepts.h>
19 #include <__type_traits/enable_if.h>
20 #include <__type_traits/is_execution_policy.h>
21 #include <__type_traits/remove_cvref.h>
22 #include <__type_traits/void_t.h>
23 #include <__utility/empty.h>
24 #include <__utility/move.h>
25 #include <optional>
26 
27 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
28 #  pragma GCC system_header
29 #endif
30 
31 _LIBCPP_PUSH_MACROS
32 #include <__undef_macros>
33 
34 #if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
35 
36 _LIBCPP_BEGIN_NAMESPACE_STD
37 
38 template <class _ExecutionPolicy,
39           class _ForwardIterator,
40           class _Function,
41           class _RawPolicy                                    = __remove_cvref_t<_ExecutionPolicy>,
42           enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
43 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<__empty>
__for_each(_ExecutionPolicy &&,_ForwardIterator && __first,_ForwardIterator && __last,_Function && __func)44 __for_each(_ExecutionPolicy&&, _ForwardIterator&& __first, _ForwardIterator&& __last, _Function&& __func) noexcept {
45   using _Backend = typename __select_backend<_RawPolicy>::type;
46   return std::__pstl_for_each<_RawPolicy>(_Backend{}, std::move(__first), std::move(__last), std::move(__func));
47 }
48 
49 template <class _ExecutionPolicy,
50           class _ForwardIterator,
51           class _Function,
52           class _RawPolicy                                    = __remove_cvref_t<_ExecutionPolicy>,
53           enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
54 _LIBCPP_HIDE_FROM_ABI void
for_each(_ExecutionPolicy && __policy,_ForwardIterator __first,_ForwardIterator __last,_Function __func)55 for_each(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Function __func) {
56   _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator);
57   if (!std::__for_each(__policy, std::move(__first), std::move(__last), std::move(__func)))
58     std::__throw_bad_alloc();
59 }
60 
61 template <class>
62 void __pstl_for_each_n(); // declaration needed for the frontend dispatch below
63 
64 template <class _ExecutionPolicy,
65           class _ForwardIterator,
66           class _Size,
67           class _Function,
68           class _RawPolicy                                    = __remove_cvref_t<_ExecutionPolicy>,
69           enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
70 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<__empty>
__for_each_n(_ExecutionPolicy && __policy,_ForwardIterator && __first,_Size && __size,_Function && __func)71 __for_each_n(_ExecutionPolicy&& __policy, _ForwardIterator&& __first, _Size&& __size, _Function&& __func) noexcept {
72   return std::__pstl_frontend_dispatch(
73       _LIBCPP_PSTL_CUSTOMIZATION_POINT(__pstl_for_each_n, _RawPolicy),
74       [&](_ForwardIterator __g_first, _Size __g_size, _Function __g_func) -> optional<__empty> {
75         if constexpr (__has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
76           std::for_each(__policy, std::move(__g_first), __g_first + __g_size, std::move(__g_func));
77           return __empty{};
78         } else {
79           std::for_each_n(std::move(__g_first), __g_size, std::move(__g_func));
80           return __empty{};
81         }
82       },
83       std::move(__first),
84       std::move(__size),
85       std::move(__func));
86 }
87 
88 template <class _ExecutionPolicy,
89           class _ForwardIterator,
90           class _Size,
91           class _Function,
92           class _RawPolicy                                    = __remove_cvref_t<_ExecutionPolicy>,
93           enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
94 _LIBCPP_HIDE_FROM_ABI void
for_each_n(_ExecutionPolicy && __policy,_ForwardIterator __first,_Size __size,_Function __func)95 for_each_n(_ExecutionPolicy&& __policy, _ForwardIterator __first, _Size __size, _Function __func) {
96   _LIBCPP_REQUIRE_CPP17_FORWARD_ITERATOR(_ForwardIterator);
97   auto __res = std::__for_each_n(__policy, std::move(__first), std::move(__size), std::move(__func));
98   if (!__res)
99     std::__throw_bad_alloc();
100 }
101 
102 _LIBCPP_END_NAMESPACE_STD
103 
104 #endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
105 
106 _LIBCPP_POP_MACROS
107 
108 #endif // _LIBCPP___ALGORITHM_PSTL_FOR_EACH_H
109