1 | // -*- C++ -*- |
2 | //===-- execution_defs.h --------------------------------------------------===// |
3 | // |
4 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
5 | // See https://llvm.org/LICENSE.txt for license information. |
6 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
7 | // |
8 | //===----------------------------------------------------------------------===// |
9 | |
10 | #ifndef _PSTL_EXECUTION_POLICY_DEFS_H |
11 | #define _PSTL_EXECUTION_POLICY_DEFS_H |
12 | |
13 | #include <type_traits> |
14 | |
15 | namespace __pstl |
16 | { |
17 | namespace execution |
18 | { |
19 | inline namespace v1 |
20 | { |
21 | |
22 | // 2.4, Sequential execution policy |
23 | class sequenced_policy |
24 | { |
25 | public: |
26 | // For internal use only |
27 | static constexpr std::false_type |
28 | __allow_unsequenced() |
29 | { |
30 | return std::false_type{}; |
31 | } |
32 | static constexpr std::false_type |
33 | __allow_vector() |
34 | { |
35 | return std::false_type{}; |
36 | } |
37 | static constexpr std::false_type |
38 | __allow_parallel() |
39 | { |
40 | return std::false_type{}; |
41 | } |
42 | }; |
43 | |
44 | // 2.5, Parallel execution policy |
45 | class parallel_policy |
46 | { |
47 | public: |
48 | // For internal use only |
49 | static constexpr std::false_type |
50 | __allow_unsequenced() |
51 | { |
52 | return std::false_type{}; |
53 | } |
54 | static constexpr std::false_type |
55 | __allow_vector() |
56 | { |
57 | return std::false_type{}; |
58 | } |
59 | static constexpr std::true_type |
60 | __allow_parallel() |
61 | { |
62 | return std::true_type{}; |
63 | } |
64 | }; |
65 | |
66 | // 2.6, Parallel+Vector execution policy |
67 | class parallel_unsequenced_policy |
68 | { |
69 | public: |
70 | // For internal use only |
71 | static constexpr std::true_type |
72 | __allow_unsequenced() |
73 | { |
74 | return std::true_type{}; |
75 | } |
76 | static constexpr std::true_type |
77 | __allow_vector() |
78 | { |
79 | return std::true_type{}; |
80 | } |
81 | static constexpr std::true_type |
82 | __allow_parallel() |
83 | { |
84 | return std::true_type{}; |
85 | } |
86 | }; |
87 | |
88 | class unsequenced_policy |
89 | { |
90 | public: |
91 | // For internal use only |
92 | static constexpr std::true_type |
93 | __allow_unsequenced() |
94 | { |
95 | return std::true_type{}; |
96 | } |
97 | static constexpr std::true_type |
98 | __allow_vector() |
99 | { |
100 | return std::true_type{}; |
101 | } |
102 | static constexpr std::false_type |
103 | __allow_parallel() |
104 | { |
105 | return std::false_type{}; |
106 | } |
107 | }; |
108 | |
109 | // 2.8, Execution policy objects |
110 | constexpr sequenced_policy seq{}; |
111 | constexpr parallel_policy par{}; |
112 | constexpr parallel_unsequenced_policy par_unseq{}; |
113 | constexpr unsequenced_policy unseq{}; |
114 | |
115 | // 2.3, Execution policy type trait |
116 | template <class _Tp> |
117 | struct is_execution_policy : std::false_type |
118 | { |
119 | }; |
120 | |
121 | template <> |
122 | struct is_execution_policy<__pstl::execution::sequenced_policy> : std::true_type |
123 | { |
124 | }; |
125 | template <> |
126 | struct is_execution_policy<__pstl::execution::parallel_policy> : std::true_type |
127 | { |
128 | }; |
129 | template <> |
130 | struct is_execution_policy<__pstl::execution::parallel_unsequenced_policy> : std::true_type |
131 | { |
132 | }; |
133 | template <> |
134 | struct is_execution_policy<__pstl::execution::unsequenced_policy> : std::true_type |
135 | { |
136 | }; |
137 | |
138 | #if _PSTL_CPP14_VARIABLE_TEMPLATES_PRESENT |
139 | template <class _Tp> |
140 | constexpr bool is_execution_policy_v = __pstl::execution::is_execution_policy<_Tp>::value; |
141 | #endif |
142 | |
143 | } // namespace v1 |
144 | } // namespace execution |
145 | |
146 | namespace __internal |
147 | { |
148 | template <class _ExecPolicy, class _Tp> |
149 | #if _GLIBCXX_RELEASE >= 9 |
150 | using __enable_if_execution_policy = |
151 | typename std::enable_if<__pstl::execution::is_execution_policy<std::__remove_cvref_t<_ExecPolicy>>::value, |
152 | _Tp>::type; |
153 | #else |
154 | using __enable_if_execution_policy = |
155 | typename std::enable_if<__pstl::execution::is_execution_policy<typename std::decay<_ExecPolicy>::type>::value, |
156 | _Tp>::type; |
157 | #endif |
158 | } // namespace __internal |
159 | |
160 | } // namespace __pstl |
161 | |
162 | #endif /* _PSTL_EXECUTION_POLICY_DEFS_H */ |
163 | |