5aaefa510e
libc++ has started splicing standard library headers into much more fine-grained content for maintainability. It's very likely that outdated and naive tooling (some of which is outside of LLVM's scope) will suggest users include things such as <__ranges/access.h> instead of <ranges>, and Hyrum's law suggests that users will eventually begin to rely on this without the help of tooling. As such, this commit intends to protect users from themselves, by making it a hard error for anyone outside of the standard library to include libc++ detail headers. Differential Revision: https://reviews.llvm.org/D106124
81 lines
2.6 KiB
C++
81 lines
2.6 KiB
C++
//===----------------------------------------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#ifndef _LIBCPP___ALGORITHM_COPY_BACKWARD_H
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#define _LIBCPP___ALGORITHM_COPY_BACKWARD_H
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#include <__algorithm/unwrap_iter.h>
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#include <__config>
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#include <__iterator/iterator_traits.h>
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#include <cstring>
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#include <type_traits>
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#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
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# pragma GCC system_header
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# pragma clang include_instead(<algorithm>)
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#endif
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_LIBCPP_BEGIN_NAMESPACE_STD
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template <class _BidirectionalIterator, class _OutputIterator>
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inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
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_OutputIterator
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__copy_backward_constexpr(_BidirectionalIterator __first, _BidirectionalIterator __last, _OutputIterator __result)
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{
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while (__first != __last)
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*--__result = *--__last;
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return __result;
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}
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template <class _BidirectionalIterator, class _OutputIterator>
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inline _LIBCPP_INLINE_VISIBILITY
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_OutputIterator
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__copy_backward(_BidirectionalIterator __first, _BidirectionalIterator __last, _OutputIterator __result)
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{
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return _VSTD::__copy_backward_constexpr(__first, __last, __result);
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}
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template <class _Tp, class _Up>
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inline _LIBCPP_INLINE_VISIBILITY
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typename enable_if
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<
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is_same<typename remove_const<_Tp>::type, _Up>::value &&
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is_trivially_copy_assignable<_Up>::value,
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_Up*
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>::type
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__copy_backward(_Tp* __first, _Tp* __last, _Up* __result)
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{
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const size_t __n = static_cast<size_t>(__last - __first);
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if (__n > 0)
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{
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__result -= __n;
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_VSTD::memmove(__result, __first, __n * sizeof(_Up));
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}
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return __result;
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}
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template <class _BidirectionalIterator1, class _BidirectionalIterator2>
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inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
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_BidirectionalIterator2
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copy_backward(_BidirectionalIterator1 __first, _BidirectionalIterator1 __last,
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_BidirectionalIterator2 __result)
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{
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if (__libcpp_is_constant_evaluated()) {
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return _VSTD::__copy_backward_constexpr(__first, __last, __result);
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} else {
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return _VSTD::__rewrap_iter(__result,
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_VSTD::__copy_backward(_VSTD::__unwrap_iter(__first),
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_VSTD::__unwrap_iter(__last),
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_VSTD::__unwrap_iter(__result)));
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}
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}
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_LIBCPP_END_NAMESPACE_STD
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#endif // _LIBCPP___ALGORITHM_COPY_BACKWARD_H
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