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 // -*- C++ -*-
 //===----------------------------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef _LIBCPP___CXX03___MEMORY_UNINITIALIZED_ALGORITHMS_H
 #define _LIBCPP___CXX03___MEMORY_UNINITIALIZED_ALGORITHMS_H
 
 #include <__cxx03/__algorithm/copy.h>
 #include <__cxx03/__algorithm/move.h>
 #include <__cxx03/__algorithm/unwrap_iter.h>
 #include <__cxx03/__algorithm/unwrap_range.h>
 #include <__cxx03/__config>
 #include <__cxx03/__iterator/iterator_traits.h>
 #include <__cxx03/__iterator/reverse_iterator.h>
 #include <__cxx03/__memory/addressof.h>
 #include <__cxx03/__memory/allocator_traits.h>
 #include <__cxx03/__memory/construct_at.h>
 #include <__cxx03/__memory/pointer_traits.h>
 #include <__cxx03/__memory/voidify.h>
 #include <__cxx03/__type_traits/extent.h>
 #include <__cxx03/__type_traits/is_array.h>
 #include <__cxx03/__type_traits/is_constant_evaluated.h>
 #include <__cxx03/__type_traits/is_trivially_assignable.h>
 #include <__cxx03/__type_traits/is_trivially_constructible.h>
 #include <__cxx03/__type_traits/is_trivially_relocatable.h>
 #include <__cxx03/__type_traits/is_unbounded_array.h>
 #include <__cxx03/__type_traits/negation.h>
 #include <__cxx03/__type_traits/remove_const.h>
 #include <__cxx03/__type_traits/remove_extent.h>
 #include <__cxx03/__utility/exception_guard.h>
 #include <__cxx03/__utility/move.h>
 #include <__cxx03/__utility/pair.h>
 #include <__cxx03/new>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
 #endif
 
 _LIBCPP_PUSH_MACROS
 #include <__cxx03/__undef_macros>
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
 struct __always_false {
   template <class... _Args>
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool operator()(_Args&&...) const _NOEXCEPT {
     return false;
   }
 };
 
 // uninitialized_copy
 
 template <class _ValueType, class _InputIterator, class _Sentinel1, class _ForwardIterator, class _EndPredicate>
 inline _LIBCPP_HIDE_FROM_ABI pair<_InputIterator, _ForwardIterator> __uninitialized_copy(
     _InputIterator __ifirst, _Sentinel1 __ilast, _ForwardIterator __ofirst, _EndPredicate __stop_copying) {
   _ForwardIterator __idx = __ofirst;
 #ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   try {
 #endif
     for (; __ifirst != __ilast && !__stop_copying(__idx); ++__ifirst, (void)++__idx)
       ::new (std::__voidify(*__idx)) _ValueType(*__ifirst);
 #ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   } catch (...) {
     std::__destroy(__ofirst, __idx);
     throw;
   }
 #endif
 
   return pair<_InputIterator, _ForwardIterator>(std::move(__ifirst), std::move(__idx));
 }
 
 template <class _InputIterator, class _ForwardIterator>
 _LIBCPP_HIDE_FROM_ABI _ForwardIterator
 uninitialized_copy(_InputIterator __ifirst, _InputIterator __ilast, _ForwardIterator __ofirst) {
   typedef typename iterator_traits<_ForwardIterator>::value_type _ValueType;
   auto __result = std::__uninitialized_copy<_ValueType>(
       std::move(__ifirst), std::move(__ilast), std::move(__ofirst), __always_false());
   return std::move(__result.second);
 }
 
 // uninitialized_copy_n
 
 template <class _ValueType, class _InputIterator, class _Size, class _ForwardIterator, class _EndPredicate>
 inline _LIBCPP_HIDE_FROM_ABI pair<_InputIterator, _ForwardIterator>
 __uninitialized_copy_n(_InputIterator __ifirst, _Size __n, _ForwardIterator __ofirst, _EndPredicate __stop_copying) {
   _ForwardIterator __idx = __ofirst;
 #ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   try {
 #endif
     for (; __n > 0 && !__stop_copying(__idx); ++__ifirst, (void)++__idx, (void)--__n)
       ::new (std::__voidify(*__idx)) _ValueType(*__ifirst);
 #ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   } catch (...) {
     std::__destroy(__ofirst, __idx);
     throw;
   }
 #endif
 
   return pair<_InputIterator, _ForwardIterator>(std::move(__ifirst), std::move(__idx));
 }
 
 template <class _InputIterator, class _Size, class _ForwardIterator>
 inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator
 uninitialized_copy_n(_InputIterator __ifirst, _Size __n, _ForwardIterator __ofirst) {
   typedef typename iterator_traits<_ForwardIterator>::value_type _ValueType;
   auto __result =
       std::__uninitialized_copy_n<_ValueType>(std::move(__ifirst), __n, std::move(__ofirst), __always_false());
   return std::move(__result.second);
 }
 
 // uninitialized_fill
 
 template <class _ValueType, class _ForwardIterator, class _Sentinel, class _Tp>
 inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator
 __uninitialized_fill(_ForwardIterator __first, _Sentinel __last, const _Tp& __x) {
   _ForwardIterator __idx = __first;
 #ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   try {
 #endif
     for (; __idx != __last; ++__idx)
       ::new (std::__voidify(*__idx)) _ValueType(__x);
 #ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   } catch (...) {
     std::__destroy(__first, __idx);
     throw;
   }
 #endif
 
   return __idx;
 }
 
 template <class _ForwardIterator, class _Tp>
 inline _LIBCPP_HIDE_FROM_ABI void
 uninitialized_fill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __x) {
   typedef typename iterator_traits<_ForwardIterator>::value_type _ValueType;
   (void)std::__uninitialized_fill<_ValueType>(__first, __last, __x);
 }
 
 // uninitialized_fill_n
 
 template <class _ValueType, class _ForwardIterator, class _Size, class _Tp>
 inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator
 __uninitialized_fill_n(_ForwardIterator __first, _Size __n, const _Tp& __x) {
   _ForwardIterator __idx = __first;
 #ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   try {
 #endif
     for (; __n > 0; ++__idx, (void)--__n)
       ::new (std::__voidify(*__idx)) _ValueType(__x);
 #ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   } catch (...) {
     std::__destroy(__first, __idx);
     throw;
   }
 #endif
 
   return __idx;
 }
 
 template <class _ForwardIterator, class _Size, class _Tp>
 inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator
 uninitialized_fill_n(_ForwardIterator __first, _Size __n, const _Tp& __x) {
   typedef typename iterator_traits<_ForwardIterator>::value_type _ValueType;
   return std::__uninitialized_fill_n<_ValueType>(__first, __n, __x);
 }
 
 #if _LIBCPP_STD_VER >= 17
 
 // uninitialized_default_construct
 
 template <class _ValueType, class _ForwardIterator, class _Sentinel>
 inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator
 __uninitialized_default_construct(_ForwardIterator __first, _Sentinel __last) {
   auto __idx = __first;
 #  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   try {
 #  endif
     for (; __idx != __last; ++__idx)
       ::new (std::__voidify(*__idx)) _ValueType;
 #  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   } catch (...) {
     std::__destroy(__first, __idx);
     throw;
   }
 #  endif
 
   return __idx;
 }
 
 template <class _ForwardIterator>
 inline _LIBCPP_HIDE_FROM_ABI void uninitialized_default_construct(_ForwardIterator __first, _ForwardIterator __last) {
   using _ValueType = typename iterator_traits<_ForwardIterator>::value_type;
   (void)std::__uninitialized_default_construct<_ValueType>(std::move(__first), std::move(__last));
 }
 
 // uninitialized_default_construct_n
 
 template <class _ValueType, class _ForwardIterator, class _Size>
 inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator __uninitialized_default_construct_n(_ForwardIterator __first, _Size __n) {
   auto __idx = __first;
 #  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   try {
 #  endif
     for (; __n > 0; ++__idx, (void)--__n)
       ::new (std::__voidify(*__idx)) _ValueType;
 #  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   } catch (...) {
     std::__destroy(__first, __idx);
     throw;
   }
 #  endif
 
   return __idx;
 }
 
 template <class _ForwardIterator, class _Size>
 inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator uninitialized_default_construct_n(_ForwardIterator __first, _Size __n) {
   using _ValueType = typename iterator_traits<_ForwardIterator>::value_type;
   return std::__uninitialized_default_construct_n<_ValueType>(std::move(__first), __n);
 }
 
 // uninitialized_value_construct
 
 template <class _ValueType, class _ForwardIterator, class _Sentinel>
 inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator
 __uninitialized_value_construct(_ForwardIterator __first, _Sentinel __last) {
   auto __idx = __first;
 #  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   try {
 #  endif
     for (; __idx != __last; ++__idx)
       ::new (std::__voidify(*__idx)) _ValueType();
 #  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   } catch (...) {
     std::__destroy(__first, __idx);
     throw;
   }
 #  endif
 
   return __idx;
 }
 
 template <class _ForwardIterator>
 inline _LIBCPP_HIDE_FROM_ABI void uninitialized_value_construct(_ForwardIterator __first, _ForwardIterator __last) {
   using _ValueType = typename iterator_traits<_ForwardIterator>::value_type;
   (void)std::__uninitialized_value_construct<_ValueType>(std::move(__first), std::move(__last));
 }
 
 // uninitialized_value_construct_n
 
 template <class _ValueType, class _ForwardIterator, class _Size>
 inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator __uninitialized_value_construct_n(_ForwardIterator __first, _Size __n) {
   auto __idx = __first;
 #  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   try {
 #  endif
     for (; __n > 0; ++__idx, (void)--__n)
       ::new (std::__voidify(*__idx)) _ValueType();
 #  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   } catch (...) {
     std::__destroy(__first, __idx);
     throw;
   }
 #  endif
 
   return __idx;
 }
 
 template <class _ForwardIterator, class _Size>
 inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator uninitialized_value_construct_n(_ForwardIterator __first, _Size __n) {
   using _ValueType = typename iterator_traits<_ForwardIterator>::value_type;
   return std::__uninitialized_value_construct_n<_ValueType>(std::move(__first), __n);
 }
 
 // uninitialized_move
 
 template <class _ValueType,
           class _InputIterator,
           class _Sentinel1,
           class _ForwardIterator,
           class _EndPredicate,
           class _IterMove>
 inline _LIBCPP_HIDE_FROM_ABI pair<_InputIterator, _ForwardIterator> __uninitialized_move(
     _InputIterator __ifirst,
     _Sentinel1 __ilast,
     _ForwardIterator __ofirst,
     _EndPredicate __stop_moving,
     _IterMove __iter_move) {
   auto __idx = __ofirst;
 #  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   try {
 #  endif
     for (; __ifirst != __ilast && !__stop_moving(__idx); ++__idx, (void)++__ifirst) {
       ::new (std::__voidify(*__idx)) _ValueType(__iter_move(__ifirst));
     }
 #  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   } catch (...) {
     std::__destroy(__ofirst, __idx);
     throw;
   }
 #  endif
 
   return {std::move(__ifirst), std::move(__idx)};
 }
 
 template <class _InputIterator, class _ForwardIterator>
 inline _LIBCPP_HIDE_FROM_ABI _ForwardIterator
 uninitialized_move(_InputIterator __ifirst, _InputIterator __ilast, _ForwardIterator __ofirst) {
   using _ValueType = typename iterator_traits<_ForwardIterator>::value_type;
   auto __iter_move = [](auto&& __iter) -> decltype(auto) { return std::move(*__iter); };
 
   auto __result = std::__uninitialized_move<_ValueType>(
       std::move(__ifirst), std::move(__ilast), std::move(__ofirst), __always_false(), __iter_move);
   return std::move(__result.second);
 }
 
 // uninitialized_move_n
 
 template <class _ValueType,
           class _InputIterator,
           class _Size,
           class _ForwardIterator,
           class _EndPredicate,
           class _IterMove>
 inline _LIBCPP_HIDE_FROM_ABI pair<_InputIterator, _ForwardIterator> __uninitialized_move_n(
     _InputIterator __ifirst, _Size __n, _ForwardIterator __ofirst, _EndPredicate __stop_moving, _IterMove __iter_move) {
   auto __idx = __ofirst;
 #  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   try {
 #  endif
     for (; __n > 0 && !__stop_moving(__idx); ++__idx, (void)++__ifirst, --__n)
       ::new (std::__voidify(*__idx)) _ValueType(__iter_move(__ifirst));
 #  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
   } catch (...) {
     std::__destroy(__ofirst, __idx);
     throw;
   }
 #  endif
 
   return {std::move(__ifirst), std::move(__idx)};
 }
 
 template <class _InputIterator, class _Size, class _ForwardIterator>
 inline _LIBCPP_HIDE_FROM_ABI pair<_InputIterator, _ForwardIterator>
 uninitialized_move_n(_InputIterator __ifirst, _Size __n, _ForwardIterator __ofirst) {
   using _ValueType = typename iterator_traits<_ForwardIterator>::value_type;
   auto __iter_move = [](auto&& __iter) -> decltype(auto) { return std::move(*__iter); };
 
   return std::__uninitialized_move_n<_ValueType>(
       std::move(__ifirst), __n, std::move(__ofirst), __always_false(), __iter_move);
 }
 
 // TODO: Rewrite this to iterate left to right and use reverse_iterators when calling
 // Destroys every element in the range [first, last) FROM RIGHT TO LEFT using allocator
 // destruction. If elements are themselves C-style arrays, they are recursively destroyed
 // in the same manner.
 //
 // This function assumes that destructors do not throw, and that the allocator is bound to
 // the correct type.
 template <class _Alloc,
           class _BidirIter,
           __enable_if_t<__has_bidirectional_iterator_category<_BidirIter>::value, int> = 0>
 _LIBCPP_HIDE_FROM_ABI constexpr void
 __allocator_destroy_multidimensional(_Alloc& __alloc, _BidirIter __first, _BidirIter __last) noexcept {
   using _ValueType = typename iterator_traits<_BidirIter>::value_type;
   static_assert(is_same_v<typename allocator_traits<_Alloc>::value_type, _ValueType>,
                 "The allocator should already be rebound to the correct type");
 
   if (__first == __last)
     return;
 
   if constexpr (is_array_v<_ValueType>) {
     static_assert(!__libcpp_is_unbounded_array<_ValueType>::value,
                   "arrays of unbounded arrays don't exist, but if they did we would mess up here");
 
     using _Element = remove_extent_t<_ValueType>;
     __allocator_traits_rebind_t<_Alloc, _Element> __elem_alloc(__alloc);
     do {
       --__last;
       decltype(auto) __array = *__last;
       std::__allocator_destroy_multidimensional(__elem_alloc, __array, __array + extent_v<_ValueType>);
     } while (__last != __first);
   } else {
     do {
       --__last;
       allocator_traits<_Alloc>::destroy(__alloc, std::addressof(*__last));
     } while (__last != __first);
   }
 }
 
 // Constructs the object at the given location using the allocator's construct method.
 //
 // If the object being constructed is an array, each element of the array is allocator-constructed,
 // recursively. If an exception is thrown during the construction of an array, the initialized
 // elements are destroyed in reverse order of initialization using allocator destruction.
 //
 // This function assumes that the allocator is bound to the correct type.
 template <class _Alloc, class _Tp>
 _LIBCPP_HIDE_FROM_ABI constexpr void __allocator_construct_at_multidimensional(_Alloc& __alloc, _Tp* __loc) {
   static_assert(is_same_v<typename allocator_traits<_Alloc>::value_type, _Tp>,
                 "The allocator should already be rebound to the correct type");
 
   if constexpr (is_array_v<_Tp>) {
     using _Element = remove_extent_t<_Tp>;
     __allocator_traits_rebind_t<_Alloc, _Element> __elem_alloc(__alloc);
     size_t __i   = 0;
     _Tp& __array = *__loc;
 
     // If an exception is thrown, destroy what we have constructed so far in reverse order.
     auto __guard = std::__make_exception_guard([&]() {
       std::__allocator_destroy_multidimensional(__elem_alloc, __array, __array + __i);
     });
 
     for (; __i != extent_v<_Tp>; ++__i) {
       std::__allocator_construct_at_multidimensional(__elem_alloc, std::addressof(__array[__i]));
     }
     __guard.__complete();
   } else {
     allocator_traits<_Alloc>::construct(__alloc, __loc);
   }
 }
 
 // Constructs the object at the given location using the allocator's construct method, passing along
 // the provided argument.
 //
 // If the object being constructed is an array, the argument is also assumed to be an array. Each
 // each element of the array being constructed is allocator-constructed from the corresponding
 // element of the argument array. If an exception is thrown during the construction of an array,
 // the initialized elements are destroyed in reverse order of initialization using allocator
 // destruction.
 //
 // This function assumes that the allocator is bound to the correct type.
 template <class _Alloc, class _Tp, class _Arg>
 _LIBCPP_HIDE_FROM_ABI constexpr void
 __allocator_construct_at_multidimensional(_Alloc& __alloc, _Tp* __loc, _Arg const& __arg) {
   static_assert(is_same_v<typename allocator_traits<_Alloc>::value_type, _Tp>,
                 "The allocator should already be rebound to the correct type");
 
   if constexpr (is_array_v<_Tp>) {
     static_assert(is_array_v<_Arg>,
                   "Provided non-array initialization argument to __allocator_construct_at_multidimensional when "
                   "trying to construct an array.");
 
     using _Element = remove_extent_t<_Tp>;
     __allocator_traits_rebind_t<_Alloc, _Element> __elem_alloc(__alloc);
     size_t __i   = 0;
     _Tp& __array = *__loc;
 
     // If an exception is thrown, destroy what we have constructed so far in reverse order.
     auto __guard = std::__make_exception_guard([&]() {
       std::__allocator_destroy_multidimensional(__elem_alloc, __array, __array + __i);
     });
     for (; __i != extent_v<_Tp>; ++__i) {
       std::__allocator_construct_at_multidimensional(__elem_alloc, std::addressof(__array[__i]), __arg[__i]);
     }
     __guard.__complete();
   } else {
     allocator_traits<_Alloc>::construct(__alloc, __loc, __arg);
   }
 }
 
 // Given a range starting at it and containing n elements, initializes each element in the
 // range from left to right using the construct method of the allocator (rebound to the
 // correct type).
 //
 // If an exception is thrown, the initialized elements are destroyed in reverse order of
 // initialization using allocator_traits destruction. If the elements in the range are C-style
 // arrays, they are initialized element-wise using allocator construction, and recursively so.
 template <class _Alloc,
           class _BidirIter,
           class _Tp,
           class _Size = typename iterator_traits<_BidirIter>::difference_type>
 _LIBCPP_HIDE_FROM_ABI constexpr void
 __uninitialized_allocator_fill_n_multidimensional(_Alloc& __alloc, _BidirIter __it, _Size __n, _Tp const& __value) {
   using _ValueType = typename iterator_traits<_BidirIter>::value_type;
   __allocator_traits_rebind_t<_Alloc, _ValueType> __value_alloc(__alloc);
   _BidirIter __begin = __it;
 
   // If an exception is thrown, destroy what we have constructed so far in reverse order.
   auto __guard =
       std::__make_exception_guard([&]() { std::__allocator_destroy_multidimensional(__value_alloc, __begin, __it); });
   for (; __n != 0; --__n, ++__it) {
     std::__allocator_construct_at_multidimensional(__value_alloc, std::addressof(*__it), __value);
   }
   __guard.__complete();
 }
 
 // Same as __uninitialized_allocator_fill_n_multidimensional, but doesn't pass any initialization argument
 // to the allocator's construct method, which results in value initialization.
 template <class _Alloc, class _BidirIter, class _Size = typename iterator_traits<_BidirIter>::difference_type>
 _LIBCPP_HIDE_FROM_ABI constexpr void
 __uninitialized_allocator_value_construct_n_multidimensional(_Alloc& __alloc, _BidirIter __it, _Size __n) {
   using _ValueType = typename iterator_traits<_BidirIter>::value_type;
   __allocator_traits_rebind_t<_Alloc, _ValueType> __value_alloc(__alloc);
   _BidirIter __begin = __it;
 
   // If an exception is thrown, destroy what we have constructed so far in reverse order.
   auto __guard =
       std::__make_exception_guard([&]() { std::__allocator_destroy_multidimensional(__value_alloc, __begin, __it); });
   for (; __n != 0; --__n, ++__it) {
     std::__allocator_construct_at_multidimensional(__value_alloc, std::addressof(*__it));
   }
   __guard.__complete();
 }
 
 #endif // _LIBCPP_STD_VER >= 17
 
 // Destroy all elements in [__first, __last) from left to right using allocator destruction.
 template <class _Alloc, class _Iter, class _Sent>
 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
 __allocator_destroy(_Alloc& __alloc, _Iter __first, _Sent __last) {
   for (; __first != __last; ++__first)
     allocator_traits<_Alloc>::destroy(__alloc, std::__to_address(__first));
 }
 
 template <class _Alloc, class _Iter>
 class _AllocatorDestroyRangeReverse {
 public:
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
   _AllocatorDestroyRangeReverse(_Alloc& __alloc, _Iter& __first, _Iter& __last)
       : __alloc_(__alloc), __first_(__first), __last_(__last) {}
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void operator()() const {
     std::__allocator_destroy(__alloc_, std::reverse_iterator<_Iter>(__last_), std::reverse_iterator<_Iter>(__first_));
   }
 
 private:
   _Alloc& __alloc_;
   _Iter& __first_;
   _Iter& __last_;
 };
 
 // Copy-construct [__first1, __last1) in [__first2, __first2 + N), where N is distance(__first1, __last1).
 //
 // The caller has to ensure that __first2 can hold at least N uninitialized elements. If an exception is thrown the
 // already copied elements are destroyed in reverse order of their construction.
 template <class _Alloc, class _Iter1, class _Sent1, class _Iter2>
 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Iter2
 __uninitialized_allocator_copy_impl(_Alloc& __alloc, _Iter1 __first1, _Sent1 __last1, _Iter2 __first2) {
   auto __destruct_first = __first2;
   auto __guard =
       std::__make_exception_guard(_AllocatorDestroyRangeReverse<_Alloc, _Iter2>(__alloc, __destruct_first, __first2));
   while (__first1 != __last1) {
     allocator_traits<_Alloc>::construct(__alloc, std::__to_address(__first2), *__first1);
     ++__first1;
     ++__first2;
   }
   __guard.__complete();
   return __first2;
 }
 
 template <class _Alloc, class _Type>
 struct __allocator_has_trivial_copy_construct : _Not<__has_construct<_Alloc, _Type*, const _Type&> > {};
 
 template <class _Type>
 struct __allocator_has_trivial_copy_construct<allocator<_Type>, _Type> : true_type {};
 
 template <class _Alloc,
           class _In,
           class _RawTypeIn = __remove_const_t<_In>,
           class _Out,
           __enable_if_t<
               // using _RawTypeIn because of the allocator<T const> extension
               is_trivially_copy_constructible<_RawTypeIn>::value && is_trivially_copy_assignable<_RawTypeIn>::value &&
                   is_same<__remove_const_t<_In>, __remove_const_t<_Out> >::value &&
                   __allocator_has_trivial_copy_construct<_Alloc, _RawTypeIn>::value,
               int> = 0>
 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Out*
 __uninitialized_allocator_copy_impl(_Alloc&, _In* __first1, _In* __last1, _Out* __first2) {
   // TODO: Remove the const_cast once we drop support for std::allocator<T const>
   if (__libcpp_is_constant_evaluated()) {
     while (__first1 != __last1) {
       std::__construct_at(std::__to_address(__first2), *__first1);
       ++__first1;
       ++__first2;
     }
     return __first2;
   } else {
     return std::copy(__first1, __last1, const_cast<_RawTypeIn*>(__first2));
   }
 }
 
 template <class _Alloc, class _Iter1, class _Sent1, class _Iter2>
 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Iter2
 __uninitialized_allocator_copy(_Alloc& __alloc, _Iter1 __first1, _Sent1 __last1, _Iter2 __first2) {
   auto __unwrapped_range = std::__unwrap_range(__first1, __last1);
   auto __result          = std::__uninitialized_allocator_copy_impl(
       __alloc, __unwrapped_range.first, __unwrapped_range.second, std::__unwrap_iter(__first2));
   return std::__rewrap_iter(__first2, __result);
 }
 
 template <class _Alloc, class _Type>
 struct __allocator_has_trivial_move_construct : _Not<__has_construct<_Alloc, _Type*, _Type&&> > {};
 
 template <class _Type>
 struct __allocator_has_trivial_move_construct<allocator<_Type>, _Type> : true_type {};
 
 template <class _Alloc, class _Tp>
 struct __allocator_has_trivial_destroy : _Not<__has_destroy<_Alloc, _Tp*> > {};
 
 template <class _Tp, class _Up>
 struct __allocator_has_trivial_destroy<allocator<_Tp>, _Up> : true_type {};
 
 // __uninitialized_allocator_relocate relocates the objects in [__first, __last) into __result.
 // Relocation means that the objects in [__first, __last) are placed into __result as-if by move-construct and destroy,
 // except that the move constructor and destructor may never be called if they are known to be equivalent to a memcpy.
 //
 // Preconditions:  __result doesn't contain any objects and [__first, __last) contains objects
 // Postconditions: __result contains the objects from [__first, __last) and
 //                 [__first, __last) doesn't contain any objects
 //
 // The strong exception guarantee is provided if any of the following are true:
 // - is_nothrow_move_constructible<_Tp>
 // - is_copy_constructible<_Tp>
 // - __libcpp_is_trivially_relocatable<_Tp>
 template <class _Alloc, class _Tp>
 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
 __uninitialized_allocator_relocate(_Alloc& __alloc, _Tp* __first, _Tp* __last, _Tp* __result) {
   static_assert(__is_cpp17_move_insertable<_Alloc>::value,
                 "The specified type does not meet the requirements of Cpp17MoveInsertable");
   if (__libcpp_is_constant_evaluated() || !__libcpp_is_trivially_relocatable<_Tp>::value ||
       !__allocator_has_trivial_move_construct<_Alloc, _Tp>::value ||
       !__allocator_has_trivial_destroy<_Alloc, _Tp>::value) {
     auto __destruct_first = __result;
     auto __guard =
         std::__make_exception_guard(_AllocatorDestroyRangeReverse<_Alloc, _Tp*>(__alloc, __destruct_first, __result));
     auto __iter = __first;
     while (__iter != __last) {
 #ifndef _LIBCPP_HAS_NO_EXCEPTIONS
       allocator_traits<_Alloc>::construct(__alloc, __result, std::move_if_noexcept(*__iter));
 #else
       allocator_traits<_Alloc>::construct(__alloc, __result, std::move(*__iter));
 #endif
       ++__iter;
       ++__result;
     }
     __guard.__complete();
     std::__allocator_destroy(__alloc, __first, __last);
   } else {
     // Casting to void* to suppress clang complaining that this is technically UB.
     __builtin_memcpy(static_cast<void*>(__result), __first, sizeof(_Tp) * (__last - __first));
   }
 }
 
 _LIBCPP_END_NAMESPACE_STD
 
 _LIBCPP_POP_MACROS
 
 #endif // _LIBCPP___CXX03___MEMORY_UNINITIALIZED_ALGORITHMS_H

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