xref: /aosp_15_r20/external/cronet/third_party/libc++/src/include/__pstl/internal/execution_defs.h (revision 6777b5387eb2ff775bb5750e3f5d96f37fb7352b)
1 // -*- C++ -*-
2 //===----------------------------------------------------------------------===//
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 <__config>
14 #include <__type_traits/decay.h>
15 #include <__type_traits/enable_if.h>
16 #include <__type_traits/integral_constant.h>
17 
18 #if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
19 
20 namespace __pstl {
21 namespace execution {
22 inline namespace v1 {
23 
24 // 2.4, Sequential execution policy
25 class sequenced_policy {};
26 
27 // 2.5, Parallel execution policy
28 class parallel_policy {};
29 
30 // 2.6, Parallel+Vector execution policy
31 class parallel_unsequenced_policy {};
32 
33 class unsequenced_policy {};
34 
35 // 2.8, Execution policy objects
36 constexpr sequenced_policy seq{};
37 constexpr parallel_policy par{};
38 constexpr parallel_unsequenced_policy par_unseq{};
39 constexpr unsequenced_policy unseq{};
40 
41 // 2.3, Execution policy type trait
42 template <class>
43 struct is_execution_policy : std::false_type {};
44 
45 template <>
46 struct is_execution_policy<__pstl::execution::sequenced_policy> : std::true_type {};
47 template <>
48 struct is_execution_policy<__pstl::execution::parallel_policy> : std::true_type {};
49 template <>
50 struct is_execution_policy<__pstl::execution::parallel_unsequenced_policy> : std::true_type {};
51 template <>
52 struct is_execution_policy<__pstl::execution::unsequenced_policy> : std::true_type {};
53 
54 template <class _Tp>
55 constexpr bool is_execution_policy_v = __pstl::execution::is_execution_policy<_Tp>::value;
56 } // namespace v1
57 } // namespace execution
58 
59 namespace __internal {
60 template <class _ExecPolicy, class _Tp>
61 using __enable_if_execution_policy =
62     typename std::enable_if<__pstl::execution::is_execution_policy<typename std::decay<_ExecPolicy>::type>::value,
63                             _Tp>::type;
64 
65 template <class _IsVector>
66 struct __serial_tag;
67 template <class _IsVector>
68 struct __parallel_tag;
69 
70 } // namespace __internal
71 
72 } // namespace __pstl
73 
74 #endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
75 
76 #endif /* _PSTL_EXECUTION_POLICY_DEFS_H */
77