1*4bdff4beSrobert //===----------------------------------------------------------------------===// 2*4bdff4beSrobert // 3*4bdff4beSrobert // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4*4bdff4beSrobert // See https://llvm.org/LICENSE.txt for license information. 5*4bdff4beSrobert // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6*4bdff4beSrobert // 7*4bdff4beSrobert //===----------------------------------------------------------------------===// 8*4bdff4beSrobert 9*4bdff4beSrobert #ifndef _LIBCPP___BIT_COUNTR_H 10*4bdff4beSrobert #define _LIBCPP___BIT_COUNTR_H 11*4bdff4beSrobert 12*4bdff4beSrobert #include <__bit/rotate.h> 13*4bdff4beSrobert #include <__concepts/arithmetic.h> 14*4bdff4beSrobert #include <__config> 15*4bdff4beSrobert #include <limits> 16*4bdff4beSrobert 17*4bdff4beSrobert #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 18*4bdff4beSrobert # pragma GCC system_header 19*4bdff4beSrobert #endif 20*4bdff4beSrobert 21*4bdff4beSrobert _LIBCPP_PUSH_MACROS 22*4bdff4beSrobert #include <__undef_macros> 23*4bdff4beSrobert 24*4bdff4beSrobert _LIBCPP_BEGIN_NAMESPACE_STD 25*4bdff4beSrobert 26*4bdff4beSrobert inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR __libcpp_ctz(unsigned __x)27*4bdff4beSrobertint __libcpp_ctz(unsigned __x) _NOEXCEPT { return __builtin_ctz(__x); } 28*4bdff4beSrobert 29*4bdff4beSrobert inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR __libcpp_ctz(unsigned long __x)30*4bdff4beSrobertint __libcpp_ctz(unsigned long __x) _NOEXCEPT { return __builtin_ctzl(__x); } 31*4bdff4beSrobert 32*4bdff4beSrobert inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR __libcpp_ctz(unsigned long long __x)33*4bdff4beSrobertint __libcpp_ctz(unsigned long long __x) _NOEXCEPT { return __builtin_ctzll(__x); } 34*4bdff4beSrobert 35*4bdff4beSrobert #if _LIBCPP_STD_VER >= 20 36*4bdff4beSrobert 37*4bdff4beSrobert template <__libcpp_unsigned_integer _Tp> countr_zero(_Tp __t)38*4bdff4beSrobert_LIBCPP_HIDE_FROM_ABI constexpr int countr_zero(_Tp __t) noexcept { 39*4bdff4beSrobert if (__t == 0) 40*4bdff4beSrobert return numeric_limits<_Tp>::digits; 41*4bdff4beSrobert 42*4bdff4beSrobert if (sizeof(_Tp) <= sizeof(unsigned int)) 43*4bdff4beSrobert return std::__libcpp_ctz(static_cast<unsigned int>(__t)); 44*4bdff4beSrobert else if (sizeof(_Tp) <= sizeof(unsigned long)) 45*4bdff4beSrobert return std::__libcpp_ctz(static_cast<unsigned long>(__t)); 46*4bdff4beSrobert else if (sizeof(_Tp) <= sizeof(unsigned long long)) 47*4bdff4beSrobert return std::__libcpp_ctz(static_cast<unsigned long long>(__t)); 48*4bdff4beSrobert else { 49*4bdff4beSrobert int __ret = 0; 50*4bdff4beSrobert const unsigned int __ulldigits = numeric_limits<unsigned long long>::digits; 51*4bdff4beSrobert while (static_cast<unsigned long long>(__t) == 0uLL) { 52*4bdff4beSrobert __ret += __ulldigits; 53*4bdff4beSrobert __t >>= __ulldigits; 54*4bdff4beSrobert } 55*4bdff4beSrobert return __ret + std::__libcpp_ctz(static_cast<unsigned long long>(__t)); 56*4bdff4beSrobert } 57*4bdff4beSrobert } 58*4bdff4beSrobert 59*4bdff4beSrobert template <__libcpp_unsigned_integer _Tp> countr_one(_Tp __t)60*4bdff4beSrobert_LIBCPP_HIDE_FROM_ABI constexpr int countr_one(_Tp __t) noexcept { 61*4bdff4beSrobert return __t != numeric_limits<_Tp>::max() ? std::countr_zero(static_cast<_Tp>(~__t)) : numeric_limits<_Tp>::digits; 62*4bdff4beSrobert } 63*4bdff4beSrobert 64*4bdff4beSrobert #endif // _LIBCPP_STD_VER >= 20 65*4bdff4beSrobert 66*4bdff4beSrobert _LIBCPP_END_NAMESPACE_STD 67*4bdff4beSrobert 68*4bdff4beSrobert _LIBCPP_POP_MACROS 69*4bdff4beSrobert 70*4bdff4beSrobert #endif // _LIBCPP___BIT_COUNTR_H 71