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_COPY_H 10 #define _LIBCPP___ALGORITHM_COPY_H 11 12 #include <__algorithm/copy_move_common.h> 13 #include <__algorithm/iterator_operations.h> 14 #include <__algorithm/min.h> 15 #include <__config> 16 #include <__iterator/segmented_iterator.h> 17 #include <__type_traits/common_type.h> 18 #include <__utility/move.h> 19 #include <__utility/pair.h> 20 21 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 22 # pragma GCC system_header 23 #endif 24 25 _LIBCPP_PUSH_MACROS 26 #include <__undef_macros> 27 28 _LIBCPP_BEGIN_NAMESPACE_STD 29 30 template <class, class _InIter, class _Sent, class _OutIter> 31 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter> __copy(_InIter, _Sent, _OutIter); 32 33 template <class _AlgPolicy> 34 struct __copy_loop { 35 template <class _InIter, class _Sent, class _OutIter> 36 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter> 37 operator()(_InIter __first, _Sent __last, _OutIter __result) const { 38 while (__first != __last) { 39 *__result = *__first; 40 ++__first; 41 ++__result; 42 } 43 44 return std::make_pair(std::move(__first), std::move(__result)); 45 } 46 47 template <class _InIter, class _OutIter, __enable_if_t<__is_segmented_iterator<_InIter>::value, int> = 0> 48 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter> 49 operator()(_InIter __first, _InIter __last, _OutIter __result) const { 50 using _Traits = __segmented_iterator_traits<_InIter>; 51 auto __sfirst = _Traits::__segment(__first); 52 auto __slast = _Traits::__segment(__last); 53 if (__sfirst == __slast) { 54 auto __iters = std::__copy<_AlgPolicy>(_Traits::__local(__first), _Traits::__local(__last), std::move(__result)); 55 return std::make_pair(__last, std::move(__iters.second)); 56 } 57 58 __result = std::__copy<_AlgPolicy>(_Traits::__local(__first), _Traits::__end(__sfirst), std::move(__result)).second; 59 ++__sfirst; 60 while (__sfirst != __slast) { 61 __result = 62 std::__copy<_AlgPolicy>(_Traits::__begin(__sfirst), _Traits::__end(__sfirst), std::move(__result)).second; 63 ++__sfirst; 64 } 65 __result = 66 std::__copy<_AlgPolicy>(_Traits::__begin(__sfirst), _Traits::__local(__last), std::move(__result)).second; 67 return std::make_pair(__last, std::move(__result)); 68 } 69 70 template <class _InIter, 71 class _OutIter, 72 __enable_if_t<__is_cpp17_random_access_iterator<_InIter>::value && 73 !__is_segmented_iterator<_InIter>::value && __is_segmented_iterator<_OutIter>::value, 74 int> = 0> 75 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter> 76 operator()(_InIter __first, _InIter __last, _OutIter __result) { 77 using _Traits = __segmented_iterator_traits<_OutIter>; 78 using _DiffT = typename common_type<__iter_diff_t<_InIter>, __iter_diff_t<_OutIter> >::type; 79 80 if (__first == __last) 81 return std::make_pair(std::move(__first), std::move(__result)); 82 83 auto __local_first = _Traits::__local(__result); 84 auto __segment_iterator = _Traits::__segment(__result); 85 while (true) { 86 auto __local_last = _Traits::__end(__segment_iterator); 87 auto __size = std::min<_DiffT>(__local_last - __local_first, __last - __first); 88 auto __iters = std::__copy<_AlgPolicy>(__first, __first + __size, __local_first); 89 __first = std::move(__iters.first); 90 91 if (__first == __last) 92 return std::make_pair(std::move(__first), _Traits::__compose(__segment_iterator, std::move(__iters.second))); 93 94 __local_first = _Traits::__begin(++__segment_iterator); 95 } 96 } 97 }; 98 99 struct __copy_trivial { 100 // At this point, the iterators have been unwrapped so any `contiguous_iterator` has been unwrapped to a pointer. 101 template <class _In, class _Out, 102 __enable_if_t<__can_lower_copy_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 pair<_InIter, _OutIter> inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 111 __copy(_InIter __first, _Sent __last, _OutIter __result) { 112 return std::__dispatch_copy_or_move<_AlgPolicy, __copy_loop<_AlgPolicy>, __copy_trivial>( 113 std::move(__first), std::move(__last), std::move(__result)); 114 } 115 116 template <class _InputIterator, class _OutputIterator> 117 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator 118 copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result) { 119 return std::__copy<_ClassicAlgPolicy>(__first, __last, __result).second; 120 } 121 122 _LIBCPP_END_NAMESPACE_STD 123 124 _LIBCPP_POP_MACROS 125 126 #endif // _LIBCPP___ALGORITHM_COPY_H 127