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 It's very likely that outdated and naive tooling (some of which is outside of LLVM's scope) will suggest users include things such as 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
51 lines
1.3 KiB
C++
51 lines
1.3 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_HALF_POSITIVE_H
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#define _LIBCPP___ALGORITHM_HALF_POSITIVE_H
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#include <__config>
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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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// Perform division by two quickly for positive integers (llvm.org/PR39129)
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template <typename _Integral>
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
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typename enable_if
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<
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is_integral<_Integral>::value,
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_Integral
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>::type
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__half_positive(_Integral __value)
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{
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return static_cast<_Integral>(static_cast<typename make_unsigned<_Integral>::type>(__value) / 2);
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}
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template <typename _Tp>
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
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typename enable_if
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<
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!is_integral<_Tp>::value,
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_Tp
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>::type
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__half_positive(_Tp __value)
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{
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return __value / 2;
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}
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_LIBCPP_END_NAMESPACE_STD
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#endif // _LIBCPP___ALGORITHM_HALF_POSITIVE_H
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