| 1 |
// -*- C++ -*- |
| 2 |
//===-- execution_impl.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_IMPL_H |
| 11 |
#define _PSTL_EXECUTION_IMPL_H |
| 12 |
|
| 13 |
#include <iterator> |
| 14 |
#include <type_traits> |
| 15 |
|
| 16 |
#include "execution_defs.h" |
| 17 |
|
| 18 |
namespace __pstl |
| 19 |
{ |
| 20 |
namespace __internal |
| 21 |
{ |
| 22 |
|
| 23 |
using namespace __pstl::execution; |
| 24 |
|
| 25 |
/* predicate */ |
| 26 |
|
| 27 |
template <typename _Tp> |
| 28 |
std::false_type __lazy_and(_Tp, std::false_type) |
| 29 |
{ |
| 30 |
return std::false_type{}; |
| 31 |
} |
| 32 |
|
| 33 |
template <typename _Tp> |
| 34 |
inline _Tp |
| 35 |
__lazy_and(_Tp __a, std::true_type) |
| 36 |
{ |
| 37 |
return __a; |
| 38 |
} |
| 39 |
|
| 40 |
template <typename _Tp> |
| 41 |
std::true_type __lazy_or(_Tp, std::true_type) |
| 42 |
{ |
| 43 |
return std::true_type{}; |
| 44 |
} |
| 45 |
|
| 46 |
template <typename _Tp> |
| 47 |
inline _Tp |
| 48 |
__lazy_or(_Tp __a, std::false_type) |
| 49 |
{ |
| 50 |
return __a; |
| 51 |
} |
| 52 |
|
| 53 |
/* iterator */ |
| 54 |
template <typename _IteratorType, typename... _OtherIteratorTypes> |
| 55 |
struct __is_random_access_iterator |
| 56 |
{ |
| 57 |
static constexpr bool value = __internal::__is_random_access_iterator<_IteratorType>::value && |
| 58 |
__internal::__is_random_access_iterator<_OtherIteratorTypes...>::value; |
| 59 |
typedef std::integral_constant<bool, value> type; |
| 60 |
}; |
| 61 |
|
| 62 |
template <typename _IteratorType> |
| 63 |
struct __is_random_access_iterator<_IteratorType> |
| 64 |
: std::is_same<typename std::iterator_traits<_IteratorType>::iterator_category, std::random_access_iterator_tag> |
| 65 |
{ |
| 66 |
}; |
| 67 |
|
| 68 |
/* policy */ |
| 69 |
template <typename _Policy> |
| 70 |
struct __policy_traits |
| 71 |
{ |
| 72 |
}; |
| 73 |
|
| 74 |
template <> |
| 75 |
struct __policy_traits<sequenced_policy> |
| 76 |
{ |
| 77 |
typedef std::false_type allow_parallel; |
| 78 |
typedef std::false_type allow_unsequenced; |
| 79 |
typedef std::false_type allow_vector; |
| 80 |
}; |
| 81 |
|
| 82 |
template <> |
| 83 |
struct __policy_traits<unsequenced_policy> |
| 84 |
{ |
| 85 |
typedef std::false_type allow_parallel; |
| 86 |
typedef std::true_type allow_unsequenced; |
| 87 |
typedef std::true_type allow_vector; |
| 88 |
}; |
| 89 |
|
| 90 |
template <> |
| 91 |
struct __policy_traits<parallel_policy> |
| 92 |
{ |
| 93 |
typedef std::true_type allow_parallel; |
| 94 |
typedef std::false_type allow_unsequenced; |
| 95 |
typedef std::false_type allow_vector; |
| 96 |
}; |
| 97 |
|
| 98 |
template <> |
| 99 |
struct __policy_traits<parallel_unsequenced_policy> |
| 100 |
{ |
| 101 |
typedef std::true_type allow_parallel; |
| 102 |
typedef std::true_type allow_unsequenced; |
| 103 |
typedef std::true_type allow_vector; |
| 104 |
}; |
| 105 |
|
| 106 |
template <typename _ExecutionPolicy> |
| 107 |
using __collector_t = |
| 108 |
typename __internal::__policy_traits<typename std::decay<_ExecutionPolicy>::type>::__collector_type; |
| 109 |
|
| 110 |
template <typename _ExecutionPolicy> |
| 111 |
using __allow_vector = |
| 112 |
typename __internal::__policy_traits<typename std::decay<_ExecutionPolicy>::type>::__allow_vector; |
| 113 |
|
| 114 |
template <typename _ExecutionPolicy> |
| 115 |
using __allow_unsequenced = |
| 116 |
typename __internal::__policy_traits<typename std::decay<_ExecutionPolicy>::type>::__allow_unsequenced; |
| 117 |
|
| 118 |
template <typename _ExecutionPolicy> |
| 119 |
using __allow_parallel = |
| 120 |
typename __internal::__policy_traits<typename std::decay<_ExecutionPolicy>::type>::__allow_parallel; |
| 121 |
|
| 122 |
template <typename _ExecutionPolicy, typename... _IteratorTypes> |
| 123 |
auto |
| 124 |
__is_vectorization_preferred(_ExecutionPolicy&& __exec) |
| 125 |
-> decltype(__internal::__lazy_and(__exec.__allow_vector(), |
| 126 |
typename __internal::__is_random_access_iterator<_IteratorTypes...>::type())) |
| 127 |
{ |
| 128 |
return __internal::__lazy_and(__exec.__allow_vector(), |
| 129 |
typename __internal::__is_random_access_iterator<_IteratorTypes...>::type()); |
| 130 |
} |
| 131 |
|
| 132 |
template <typename _ExecutionPolicy, typename... _IteratorTypes> |
| 133 |
auto |
| 134 |
__is_parallelization_preferred(_ExecutionPolicy&& __exec) |
| 135 |
-> decltype(__internal::__lazy_and(__exec.__allow_parallel(), |
| 136 |
typename __internal::__is_random_access_iterator<_IteratorTypes...>::type())) |
| 137 |
{ |
| 138 |
return __internal::__lazy_and(__exec.__allow_parallel(), |
| 139 |
typename __internal::__is_random_access_iterator<_IteratorTypes...>::type()); |
| 140 |
} |
| 141 |
|
| 142 |
template <typename policy, typename... _IteratorTypes> |
| 143 |
struct __prefer_unsequenced_tag |
| 144 |
{ |
| 145 |
static constexpr bool value = __internal::__allow_unsequenced<policy>::value && |
| 146 |
__internal::__is_random_access_iterator<_IteratorTypes...>::value; |
| 147 |
typedef std::integral_constant<bool, value> type; |
| 148 |
}; |
| 149 |
|
| 150 |
template <typename policy, typename... _IteratorTypes> |
| 151 |
struct __prefer_parallel_tag |
| 152 |
{ |
| 153 |
static constexpr bool value = __internal::__allow_parallel<policy>::value && |
| 154 |
__internal::__is_random_access_iterator<_IteratorTypes...>::value; |
| 155 |
typedef std::integral_constant<bool, value> type; |
| 156 |
}; |
| 157 |
|
| 158 |
} // namespace __internal |
| 159 |
} // namespace __pstl |
| 160 |
|
| 161 |
#endif /* _PSTL_EXECUTION_IMPL_H */ |
