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_MOVE_H
10 #define _LIBCPP___ALGORITHM_PSTL_MOVE_H
11 
12 #include <__algorithm/copy_n.h>
13 #include <__algorithm/pstl_backend.h>
14 #include <__algorithm/pstl_frontend_dispatch.h>
15 #include <__algorithm/pstl_transform.h>
16 #include <__config>
17 #include <__functional/identity.h>
18 #include <__iterator/iterator_traits.h>
19 #include <__type_traits/enable_if.h>
20 #include <__type_traits/is_constant_evaluated.h>
21 #include <__type_traits/is_execution_policy.h>
22 #include <__type_traits/is_trivially_copyable.h>
23 #include <__type_traits/remove_cvref.h>
24 #include <optional>
25 
26 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
27 #  pragma GCC system_header
28 #endif
29 
30 _LIBCPP_PUSH_MACROS
31 #include <__undef_macros>
32 
33 #if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
34 
35 _LIBCPP_BEGIN_NAMESPACE_STD
36 
37 // TODO: Use the std::copy/move shenanigans to forward to std::memmove
38 //       Investigate whether we want to still forward to std::transform(policy)
39 //       in that case for the execution::par part, or whether we actually want
40 //       to run everything serially in that case.
41 
42 template <class>
43 void __pstl_move();
44 
45 template <class _ExecutionPolicy,
46           class _ForwardIterator,
47           class _ForwardOutIterator,
48           class _RawPolicy                                    = __remove_cvref_t<_ExecutionPolicy>,
49           enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
50 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator>
51 __move(_ExecutionPolicy&& __policy,
52        _ForwardIterator&& __first,
53        _ForwardIterator&& __last,
54        _ForwardOutIterator&& __result) noexcept {
55   return std::__pstl_frontend_dispatch(
56       _LIBCPP_PSTL_CUSTOMIZATION_POINT(__pstl_move, _RawPolicy),
57       [&__policy](_ForwardIterator __g_first, _ForwardIterator __g_last, _ForwardOutIterator __g_result) {
58         return std::__transform(__policy, __g_first, __g_last, __g_result, [](auto&& __v) { return std::move(__v); });
59       },
60       std::move(__first),
61       std::move(__last),
62       std::move(__result));
63 }
64 
65 template <class _ExecutionPolicy,
66           class _ForwardIterator,
67           class _ForwardOutIterator,
68           class _RawPolicy                                    = __remove_cvref_t<_ExecutionPolicy>,
69           enable_if_t<is_execution_policy_v<_RawPolicy>, int> = 0>
70 _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator
71 move(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _ForwardOutIterator __result) {
72   auto __res = std::__move(__policy, std::move(__first), std::move(__last), std::move(__result));
73   if (!__res)
74     std::__throw_bad_alloc();
75   return *__res;
76 }
77 
78 _LIBCPP_END_NAMESPACE_STD
79 
80 #endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
81 
82 _LIBCPP_POP_MACROS
83 
84 #endif // _LIBCPP___ALGORITHM_PSTL_MOVE_H
85