1*bdd1243dSDimitry Andric //===----------------------------------------------------------------------===// 2*bdd1243dSDimitry Andric // 3*bdd1243dSDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4*bdd1243dSDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 5*bdd1243dSDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6*bdd1243dSDimitry Andric // 7*bdd1243dSDimitry Andric //===----------------------------------------------------------------------===// 8*bdd1243dSDimitry Andric 9*bdd1243dSDimitry Andric #ifndef _LIBCPP___BIT_BIT_WIDTH_H 10*bdd1243dSDimitry Andric #define _LIBCPP___BIT_BIT_WIDTH_H 11*bdd1243dSDimitry Andric 12*bdd1243dSDimitry Andric #include <__bit/bit_log2.h> 13*bdd1243dSDimitry Andric #include <__concepts/arithmetic.h> 14*bdd1243dSDimitry Andric #include <__config> 15*bdd1243dSDimitry Andric 16*bdd1243dSDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 17*bdd1243dSDimitry Andric # pragma GCC system_header 18*bdd1243dSDimitry Andric #endif 19*bdd1243dSDimitry Andric 20*bdd1243dSDimitry Andric #if _LIBCPP_STD_VER >= 20 21*bdd1243dSDimitry Andric 22*bdd1243dSDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD 23*bdd1243dSDimitry Andric 24*bdd1243dSDimitry Andric template <__libcpp_unsigned_integer _Tp> 25*bdd1243dSDimitry Andric _LIBCPP_HIDE_FROM_ABI constexpr int bit_width(_Tp __t) noexcept { 26*bdd1243dSDimitry Andric return __t == 0 ? 0 : std::__bit_log2(__t) + 1; 27*bdd1243dSDimitry Andric } 28*bdd1243dSDimitry Andric 29*bdd1243dSDimitry Andric _LIBCPP_END_NAMESPACE_STD 30*bdd1243dSDimitry Andric 31*bdd1243dSDimitry Andric #endif // _LIBCPP_STD_VER >= 20 32*bdd1243dSDimitry Andric 33*bdd1243dSDimitry Andric #endif // _LIBCPP___BIT_BIT_WIDTH_H 34