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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_WIDTH_H10#define _LIBCPP___BIT_BIT_WIDTH_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#if _LIBCPP_STD_VER >= 2021 22_LIBCPP_BEGIN_NAMESPACE_STD23 24template <__unsigned_integer _Tp>25[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr int bit_width(_Tp __t) noexcept {26 return __t == 0 ? 0 : std::__bit_log2(__t) + 1;27}28 29_LIBCPP_END_NAMESPACE_STD30 31#endif // _LIBCPP_STD_VER >= 2032 33#endif // _LIBCPP___BIT_BIT_WIDTH_H34