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1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef _LIBCPP___BIT_BIT_FLOOR_H10#define _LIBCPP___BIT_BIT_FLOOR_H11 12#include <__bit/bit_log2.h>13#include <__config>14#include <__type_traits/integer_traits.h>15 16#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)17# pragma GCC system_header18#endif19 20_LIBCPP_BEGIN_NAMESPACE_STD21 22#if _LIBCPP_STD_VER >= 2023 24template <__unsigned_integer _Tp>25[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Tp bit_floor(_Tp __t) noexcept {26 return __t == 0 ? 0 : _Tp{1} << std::__bit_log2(__t);27}28 29#endif // _LIBCPP_STD_VER >= 2030 31_LIBCPP_END_NAMESPACE_STD32 33#endif // _LIBCPP___BIT_BIT_FLOOR_H34