Upgrade to 2022-era LLVM LIBCXX

third_party/libcxx/__algorithm/move.h

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+//===----------------------------------------------------------------------===//
+//
+// 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___ALGORITHM_MOVE_H
+#define _LIBCPP___ALGORITHM_MOVE_H
+
+#include <__algorithm/copy_move_common.h>
+#include <__algorithm/for_each_segment.h>
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/min.h>
+#include <__config>
+#include <__iterator/segmented_iterator.h>
+#include <__type_traits/common_type.h>
+#include <__type_traits/is_copy_constructible.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy, class _InIter, class _Sent, class _OutIter>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+__move(_InIter __first, _Sent __last, _OutIter __result);
+
+template <class _AlgPolicy>
+struct __move_loop {
+  template <class _InIter, class _Sent, class _OutIter>
+  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+  operator()(_InIter __first, _Sent __last, _OutIter __result) const {
+    while (__first != __last) {
+      *__result = _IterOps<_AlgPolicy>::__iter_move(__first);
+      ++__first;
+      ++__result;
+    }
+    return std::make_pair(std::move(__first), std::move(__result));
+  }
+
+  template <class _InIter, class _OutIter>
+  struct _MoveSegment {
+    using _Traits = __segmented_iterator_traits<_InIter>;
+
+    _OutIter& __result_;
+
+    _LIBCPP_HIDE_FROM_ABI _MoveSegment(_OutIter& __result) : __result_(__result) {}
+
+    _LIBCPP_HIDE_FROM_ABI void
+    operator()(typename _Traits::__local_iterator __lfirst, typename _Traits::__local_iterator __llast) {
+      __result_ = std::__move<_AlgPolicy>(__lfirst, __llast, std::move(__result_)).second;
+    }
+  };
+
+  template <class _InIter, class _OutIter, __enable_if_t<__is_segmented_iterator<_InIter>::value, int> = 0>
+  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+  operator()(_InIter __first, _InIter __last, _OutIter __result) const {
+    std::__for_each_segment(__first, __last, _MoveSegment<_InIter, _OutIter>(__result));
+    return std::make_pair(__last, std::move(__result));
+  }
+
+  template <class _InIter,
+            class _OutIter,
+            __enable_if_t<__has_random_access_iterator_category<_InIter>::value &&
+                              !__is_segmented_iterator<_InIter>::value && __is_segmented_iterator<_OutIter>::value,
+                          int> = 0>
+  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+  operator()(_InIter __first, _InIter __last, _OutIter __result) {
+    using _Traits = __segmented_iterator_traits<_OutIter>;
+    using _DiffT  = typename common_type<__iter_diff_t<_InIter>, __iter_diff_t<_OutIter> >::type;
+
+    if (__first == __last)
+      return std::make_pair(std::move(__first), std::move(__result));
+
+    auto __local_first      = _Traits::__local(__result);
+    auto __segment_iterator = _Traits::__segment(__result);
+    while (true) {
+      auto __local_last = _Traits::__end(__segment_iterator);
+      auto __size       = std::min<_DiffT>(__local_last - __local_first, __last - __first);
+      auto __iters      = std::__move<_AlgPolicy>(__first, __first + __size, __local_first);
+      __first           = std::move(__iters.first);
+
+      if (__first == __last)
+        return std::make_pair(std::move(__first), _Traits::__compose(__segment_iterator, std::move(__iters.second)));
+
+      __local_first = _Traits::__begin(++__segment_iterator);
+    }
+  }
+};
+
+struct __move_trivial {
+  // At this point, the iterators have been unwrapped so any `contiguous_iterator` has been unwrapped to a pointer.
+  template <class _In, class _Out,
+            __enable_if_t<__can_lower_move_assignment_to_memmove<_In, _Out>::value, int> = 0>
+  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_In*, _Out*>
+  operator()(_In* __first, _In* __last, _Out* __result) const {
+    return std::__copy_trivial_impl(__first, __last, __result);
+  }
+};
+
+template <class _AlgPolicy, class _InIter, class _Sent, class _OutIter>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+__move(_InIter __first, _Sent __last, _OutIter __result) {
+  return std::__dispatch_copy_or_move<_AlgPolicy, __move_loop<_AlgPolicy>, __move_trivial>(
+      std::move(__first), std::move(__last), std::move(__result));
+}
+
+template <class _InputIterator, class _OutputIterator>
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
+move(_InputIterator __first, _InputIterator __last, _OutputIterator __result) {
+  static_assert(is_copy_constructible<_InputIterator>::value, "Iterators has to be copy constructible.");
+  static_assert(is_copy_constructible<_OutputIterator>::value, "The output iterator has to be copy constructible.");
+
+  return std::__move<_ClassicAlgPolicy>(std::move(__first), std::move(__last), std::move(__result)).second;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_MOVE_H