Sprout/sprout/math/fpclassify.hpp
2014-01-08 16:48:12 +09:00

68 lines
2 KiB
C++

/*=============================================================================
Copyright (c) 2011-2014 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_MATH_FPCLASSIFY_HPP
#define SPROUT_MATH_FPCLASSIFY_HPP
#include <cmath>
#include <type_traits>
#include <sprout/config.hpp>
#include <sprout/type_traits/enabler_if.hpp>
#include <sprout/math/detail/config.hpp>
#include <sprout/math/isnan.hpp>
#include <sprout/math/isinf.hpp>
#include <sprout/math/iszero.hpp>
#include <sprout/math/issubnormal.hpp>
namespace sprout {
namespace math {
namespace detail {
#if SPROUT_USE_BUILTIN_CMATH_FUNCTION
template<typename FloatType>
inline SPROUT_CONSTEXPR int
builtin_fpclassify(FloatType x) {
return __builtin_fpclassify(FP_NAN, FP_INFINITE, FP_NORMAL, FP_SUBNORMAL, FP_ZERO, x);
}
#endif
} // namespace detail
//
// fpclassify
//
template<
typename FloatType,
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
>
inline SPROUT_CONSTEXPR int
fpclassify(FloatType x) {
return
#if SPROUT_USE_BUILTIN_CMATH_FUNCTION
sprout::math::detail::builtin_fpclassify(x)
#else
sprout::math::isnan(x) ? FP_NAN
: sprout::math::isinf(x) ? FP_INFINITE
: sprout::math::iszero(x) ? FP_ZERO
: sprout::math::detail::issubnormal_or_zero(x) ? FP_SUBNORMAL
: FP_NORMAL
#endif
;
}
template<
typename IntType,
typename sprout::enabler_if<std::is_integral<IntType>::value>::type = sprout::enabler
>
inline SPROUT_CONSTEXPR int
fpclassify(IntType x) {
return x ? FP_NORMAL
: FP_ZERO
;
}
} // namespace math
using sprout::math::fpclassify;
} // namespace sprout
#endif // #ifndef SPROUT_MATH_FPCLASSIFY_HPP