mirror of
https://github.com/bolero-MURAKAMI/Sprout.git
synced 2024-11-29 01:03:45 +00:00
50 lines
1.4 KiB
C++
50 lines
1.4 KiB
C++
/*=============================================================================
|
|
Copyright (c) 2011-2017 Bolero MURAKAMI
|
|
https://github.com/bolero-MURAKAMI/Sprout
|
|
|
|
Distributed under the Boost Software License, Version 1.0. (See accompanying
|
|
file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
|
|
=============================================================================*/
|
|
#ifndef SPROUT_BIT_CLRSB_HPP
|
|
#define SPROUT_BIT_CLRSB_HPP
|
|
|
|
#include <type_traits>
|
|
#include <sprout/config.hpp>
|
|
#include <sprout/bit/clz.hpp>
|
|
|
|
namespace sprout {
|
|
namespace detail {
|
|
# if SPROUT_USE_BUILTIN_BIT_OPERATION
|
|
inline SPROUT_CONSTEXPR int
|
|
clrsb(unsigned x) {
|
|
return __builtin_clrsb(x);
|
|
}
|
|
inline SPROUT_CONSTEXPR int
|
|
clrsb(unsigned long x) {
|
|
return __builtin_clrsbl(x);
|
|
}
|
|
inline SPROUT_CONSTEXPR int
|
|
clrsb(unsigned long long x) {
|
|
return __builtin_clrsbll(x);
|
|
}
|
|
# endif
|
|
template<typename Integral>
|
|
inline SPROUT_CONSTEXPR int
|
|
clrsb(Integral x) SPROUT_NOEXCEPT {
|
|
return sprout::clz(~x);
|
|
}
|
|
} // namespace detail
|
|
//
|
|
// clrsb
|
|
//
|
|
template<typename Integral>
|
|
inline SPROUT_CONSTEXPR typename std::enable_if<
|
|
std::is_integral<Integral>::value,
|
|
int
|
|
>::type
|
|
clrsb(Integral x) SPROUT_NOEXCEPT {
|
|
return sprout::detail::clrsb(x);
|
|
}
|
|
} // namespace sprout
|
|
|
|
#endif // #ifndef SPROUT_BIT_CLRSB_HPP
|