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/unwrap_iter.h> 13 #include <__config> 14 #include <__iterator/iterator_traits.h> 15 #include <__iterator/reverse_iterator.h> 16 #include <__utility/move.h> 17 #include <__utility/pair.h> 18 #include <cstring> 19 #include <type_traits> 20 21 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 22 # pragma GCC system_header 23 #endif 24 25 _LIBCPP_BEGIN_NAMESPACE_STD 26 27 // copy 28 29 template <class _InIter, class _Sent, class _OutIter> 30 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 31 pair<_InIter, _OutIter> __copy_impl(_InIter __first, _Sent __last, _OutIter __result) { 32 while (__first != __last) { 33 *__result = *__first; 34 ++__first; 35 ++__result; 36 } 37 return pair<_InIter, _OutIter>(std::move(__first), std::move(__result)); 38 } 39 40 template <class _InValueT, 41 class _OutValueT, 42 class = __enable_if_t<is_same<typename remove_const<_InValueT>::type, _OutValueT>::value 43 && is_trivially_copy_assignable<_OutValueT>::value> > 44 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 45 pair<_InValueT*, _OutValueT*> __copy_impl(_InValueT* __first, _InValueT* __last, _OutValueT* __result) { 46 if (__libcpp_is_constant_evaluated() 47 // TODO: Remove this once GCC supports __builtin_memmove during constant evaluation 48 #ifndef _LIBCPP_COMPILER_GCC 49 && !is_trivially_copyable<_InValueT>::value 50 #endif 51 ) 52 return std::__copy_impl<_InValueT*, _InValueT*, _OutValueT*>(__first, __last, __result); 53 const size_t __n = static_cast<size_t>(__last - __first); 54 if (__n > 0) 55 ::__builtin_memmove(__result, __first, __n * sizeof(_OutValueT)); 56 return std::make_pair(__first + __n, __result + __n); 57 } 58 59 template <class _InIter, class _OutIter, 60 __enable_if_t<is_same<typename remove_const<__iter_value_type<_InIter> >::type, __iter_value_type<_OutIter> >::value 61 && __is_cpp17_contiguous_iterator<_InIter>::value 62 && __is_cpp17_contiguous_iterator<_OutIter>::value 63 && is_trivially_copy_assignable<__iter_value_type<_OutIter> >::value, int> = 0> 64 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 65 pair<reverse_iterator<_InIter>, reverse_iterator<_OutIter> > 66 __copy_impl(reverse_iterator<_InIter> __first, 67 reverse_iterator<_InIter> __last, 68 reverse_iterator<_OutIter> __result) { 69 auto __first_base = std::__unwrap_iter(__first.base()); 70 auto __last_base = std::__unwrap_iter(__last.base()); 71 auto __result_base = std::__unwrap_iter(__result.base()); 72 auto __result_first = __result_base - (__first_base - __last_base); 73 std::__copy_impl(__last_base, __first_base, __result_first); 74 return std::make_pair(__last, reverse_iterator<_OutIter>(std::__rewrap_iter(__result.base(), __result_first))); 75 } 76 77 template <class _InIter, class _Sent, class _OutIter, 78 __enable_if_t<!(is_copy_constructible<_InIter>::value 79 && is_copy_constructible<_Sent>::value 80 && is_copy_constructible<_OutIter>::value), int> = 0 > 81 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 82 pair<_InIter, _OutIter> __copy(_InIter __first, _Sent __last, _OutIter __result) { 83 return std::__copy_impl(std::move(__first), std::move(__last), std::move(__result)); 84 } 85 86 template <class _InIter, class _Sent, class _OutIter, 87 __enable_if_t<is_copy_constructible<_InIter>::value 88 && is_copy_constructible<_Sent>::value 89 && is_copy_constructible<_OutIter>::value, int> = 0> 90 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 91 pair<_InIter, _OutIter> 92 __copy(_InIter __first, _Sent __last, _OutIter __result) { 93 auto __ret = std::__copy_impl(std::__unwrap_iter(__first), std::__unwrap_iter(__last), std::__unwrap_iter(__result)); 94 return std::make_pair(std::__rewrap_iter(__first, __ret.first), std::__rewrap_iter(__result, __ret.second)); 95 } 96 97 template <class _InputIterator, class _OutputIterator> 98 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 99 _OutputIterator 100 copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result) { 101 return std::__copy(__first, __last, __result).second; 102 } 103 104 _LIBCPP_END_NAMESPACE_STD 105 106 #endif // _LIBCPP___ALGORITHM_COPY_H 107