1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
|
// -*- C++ -*-
//===-- execution_impl.h --------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _PSTL_EXECUTION_IMPL_H
#define _PSTL_EXECUTION_IMPL_H
#include <iterator>
#include <type_traits>
#include "execution_defs.h"
namespace __pstl
{
namespace __internal
{
#if __glibcxx_concepts
template<typename _Iter>
concept __is_random_access_iter
= std::is_base_of_v<std::random_access_iterator_tag,
std::__iter_category_t<_Iter>>
|| std::random_access_iterator<_Iter>;
template <typename... _IteratorTypes>
using __are_random_access_iterators
= std::bool_constant<(__is_random_access_iter<std::remove_cvref_t<_IteratorTypes>> && ...)>;
#else
template <typename... _IteratorTypes>
using __are_random_access_iterators
= std::__and_<
std::is_base_of<std::random_access_iterator_tag,
std::__iter_category_t<std::__remove_cvref_t<_IteratorTypes>>>...
>;
#endif
struct __serial_backend_tag
{
};
struct __tbb_backend_tag
{
};
struct __openmp_backend_tag
{
};
#if defined(_PSTL_PAR_BACKEND_TBB)
using __par_backend_tag = __tbb_backend_tag;
#elif defined(_PSTL_PAR_BACKEND_OPENMP)
using __par_backend_tag = __openmp_backend_tag;
#elif defined(_PSTL_PAR_BACKEND_SERIAL)
using __par_backend_tag = __serial_backend_tag;
#else
# error "A parallel backend must be specified";
#endif
template <class _IsVector>
struct __serial_tag
{
using __is_vector = _IsVector;
};
template <class _IsVector>
struct __parallel_tag
{
using __is_vector = _IsVector;
// backend tag can be change depending on
// TBB availability in the environment
using __backend_tag = __par_backend_tag;
};
template <class _IsVector, class... _IteratorTypes>
using __tag_type = typename std::conditional<__internal::__are_random_access_iterators<_IteratorTypes...>::value,
__parallel_tag<_IsVector>, __serial_tag<_IsVector>>::type;
template <class... _IteratorTypes>
__serial_tag</*_IsVector = */ std::false_type>
__select_backend(__pstl::execution::sequenced_policy, _IteratorTypes&&...)
{
return {};
}
template <class... _IteratorTypes>
__serial_tag<__internal::__are_random_access_iterators<_IteratorTypes...>>
__select_backend(__pstl::execution::unsequenced_policy, _IteratorTypes&&...)
{
return {};
}
template <class... _IteratorTypes>
__tag_type</*_IsVector = */ std::false_type, _IteratorTypes...>
__select_backend(__pstl::execution::parallel_policy, _IteratorTypes&&...)
{
return {};
}
template <class... _IteratorTypes>
__tag_type<__internal::__are_random_access_iterators<_IteratorTypes...>, _IteratorTypes...>
__select_backend(__pstl::execution::parallel_unsequenced_policy, _IteratorTypes&&...)
{
return {};
}
} // namespace __internal
} // namespace __pstl
#endif /* _PSTL_EXECUTION_IMPL_H */
|
