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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_HALF_POSITIVE_H
#define _LIBCPP___ALGORITHM_HALF_POSITIVE_H
#include <__config>
#include <__type_traits/enable_if.h>
#include <__type_traits/is_integral.h>
#include <__type_traits/make_unsigned.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
// Perform division by two quickly for positive integers (llvm.org/PR39129)
template <typename _Integral, __enable_if_t<is_integral<_Integral>::value, int> = 0>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
_Integral
__half_positive(_Integral __value)
{
return static_cast<_Integral>(static_cast<__make_unsigned_t<_Integral> >(__value) / 2);
}
template <typename _Tp, __enable_if_t<!is_integral<_Tp>::value, int> = 0>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
_Tp
__half_positive(_Tp __value)
{
return __value / 2;
}
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___ALGORITHM_HALF_POSITIVE_H
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