xref: /freebsd/contrib/llvm-project/libcxx/include/__algorithm/move.h (revision 349cc55c9796c4596a5b9904cd3281af295f878f)
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_MOVE_H
10 #define _LIBCPP___ALGORITHM_MOVE_H
11 
12 #include <__config>
13 #include <__algorithm/unwrap_iter.h>
14 #include <__utility/move.h>
15 #include <cstring>
16 #include <utility>
17 #include <type_traits>
18 
19 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
20 #pragma GCC system_header
21 #endif
22 
23 _LIBCPP_BEGIN_NAMESPACE_STD
24 
25 // move
26 
27 template <class _InputIterator, class _OutputIterator>
28 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
29 _OutputIterator
30 __move_constexpr(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
31 {
32     for (; __first != __last; ++__first, (void) ++__result)
33         *__result = _VSTD::move(*__first);
34     return __result;
35 }
36 
37 template <class _InputIterator, class _OutputIterator>
38 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
39 _OutputIterator
40 __move(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
41 {
42     return _VSTD::__move_constexpr(__first, __last, __result);
43 }
44 
45 template <class _Tp, class _Up>
46 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
47 typename enable_if
48 <
49     is_same<typename remove_const<_Tp>::type, _Up>::value &&
50     is_trivially_move_assignable<_Up>::value,
51     _Up*
52 >::type
53 __move(_Tp* __first, _Tp* __last, _Up* __result)
54 {
55     const size_t __n = static_cast<size_t>(__last - __first);
56     if (__n > 0)
57         _VSTD::memmove(__result, __first, __n * sizeof(_Up));
58     return __result + __n;
59 }
60 
61 template <class _InputIterator, class _OutputIterator>
62 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
63 _OutputIterator
64 move(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
65 {
66     if (__libcpp_is_constant_evaluated()) {
67         return _VSTD::__move_constexpr(__first, __last, __result);
68     } else {
69         return _VSTD::__rewrap_iter(__result,
70             _VSTD::__move(_VSTD::__unwrap_iter(__first),
71                           _VSTD::__unwrap_iter(__last),
72                           _VSTD::__unwrap_iter(__result)));
73     }
74 }
75 
76 _LIBCPP_END_NAMESPACE_STD
77 
78 #endif // _LIBCPP___ALGORITHM_MOVE_H
79