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 <__algorithm/copy_move_common.h> 13 #include <__algorithm/for_each_segment.h> 14 #include <__algorithm/iterator_operations.h> 15 #include <__algorithm/min.h> 16 #include <__config> 17 #include <__iterator/iterator_traits.h> 18 #include <__iterator/segmented_iterator.h> 19 #include <__type_traits/common_type.h> 20 #include <__type_traits/enable_if.h> 21 #include <__type_traits/is_constructible.h> 22 #include <__utility/move.h> 23 #include <__utility/pair.h> 24 25 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 26 # pragma GCC system_header 27 #endif 28 29 _LIBCPP_PUSH_MACROS 30 #include <__undef_macros> 31 32 _LIBCPP_BEGIN_NAMESPACE_STD 33 34 template <class _AlgPolicy, class _InIter, class _Sent, class _OutIter> 35 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter> 36 __move(_InIter __first, _Sent __last, _OutIter __result); 37 38 template <class _AlgPolicy> 39 struct __move_impl { 40 template <class _InIter, class _Sent, class _OutIter> 41 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter> 42 operator()(_InIter __first, _Sent __last, _OutIter __result) const { 43 while (__first != __last) { 44 *__result = _IterOps<_AlgPolicy>::__iter_move(__first); 45 ++__first; 46 ++__result; 47 } 48 return std::make_pair(std::move(__first), std::move(__result)); 49 } 50 51 template <class _InIter, class _OutIter> 52 struct _MoveSegment { 53 using _Traits _LIBCPP_NODEBUG = __segmented_iterator_traits<_InIter>; 54 55 _OutIter& __result_; 56 57 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit _MoveSegment(_OutIter& __result) 58 : __result_(__result) {} 59 60 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void 61 operator()(typename _Traits::__local_iterator __lfirst, typename _Traits::__local_iterator __llast) { 62 __result_ = std::__move<_AlgPolicy>(__lfirst, __llast, std::move(__result_)).second; 63 } 64 }; 65 66 template <class _InIter, class _OutIter, __enable_if_t<__is_segmented_iterator<_InIter>::value, int> = 0> 67 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter> 68 operator()(_InIter __first, _InIter __last, _OutIter __result) const { 69 std::__for_each_segment(__first, __last, _MoveSegment<_InIter, _OutIter>(__result)); 70 return std::make_pair(__last, std::move(__result)); 71 } 72 73 template <class _InIter, 74 class _OutIter, 75 __enable_if_t<__has_random_access_iterator_category<_InIter>::value && 76 !__is_segmented_iterator<_InIter>::value && __is_segmented_iterator<_OutIter>::value, 77 int> = 0> 78 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter> 79 operator()(_InIter __first, _InIter __last, _OutIter __result) const { 80 using _Traits = __segmented_iterator_traits<_OutIter>; 81 using _DiffT = typename common_type<__iter_diff_t<_InIter>, __iter_diff_t<_OutIter> >::type; 82 83 if (__first == __last) 84 return std::make_pair(std::move(__first), std::move(__result)); 85 86 auto __local_first = _Traits::__local(__result); 87 auto __segment_iterator = _Traits::__segment(__result); 88 while (true) { 89 auto __local_last = _Traits::__end(__segment_iterator); 90 auto __size = std::min<_DiffT>(__local_last - __local_first, __last - __first); 91 auto __iters = std::__move<_AlgPolicy>(__first, __first + __size, __local_first); 92 __first = std::move(__iters.first); 93 94 if (__first == __last) 95 return std::make_pair(std::move(__first), _Traits::__compose(__segment_iterator, std::move(__iters.second))); 96 97 __local_first = _Traits::__begin(++__segment_iterator); 98 } 99 } 100 101 // At this point, the iterators have been unwrapped so any `contiguous_iterator` has been unwrapped to a pointer. 102 template <class _In, class _Out, __enable_if_t<__can_lower_move_assignment_to_memmove<_In, _Out>::value, int> = 0> 103 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_In*, _Out*> 104 operator()(_In* __first, _In* __last, _Out* __result) const { 105 return std::__copy_trivial_impl(__first, __last, __result); 106 } 107 }; 108 109 template <class _AlgPolicy, class _InIter, class _Sent, class _OutIter> 110 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter> 111 __move(_InIter __first, _Sent __last, _OutIter __result) { 112 return std::__copy_move_unwrap_iters<__move_impl<_AlgPolicy> >( 113 std::move(__first), std::move(__last), std::move(__result)); 114 } 115 116 template <class _InputIterator, class _OutputIterator> 117 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator 118 move(_InputIterator __first, _InputIterator __last, _OutputIterator __result) { 119 static_assert(is_copy_constructible<_InputIterator>::value, "Iterators has to be copy constructible."); 120 static_assert(is_copy_constructible<_OutputIterator>::value, "The output iterator has to be copy constructible."); 121 122 return std::__move<_ClassicAlgPolicy>(std::move(__first), std::move(__last), std::move(__result)).second; 123 } 124 125 _LIBCPP_END_NAMESPACE_STD 126 127 _LIBCPP_POP_MACROS 128 129 #endif // _LIBCPP___ALGORITHM_MOVE_H 130