Swiftdiff options
Diffstat (limited to '3rdParty/Boost/src/boost/math/special_functions/sign.hpp')
| -rw-r--r-- | 3rdParty/Boost/src/boost/math/special_functions/sign.hpp | 71 |
1 files changed, 60 insertions, 11 deletions
diff --git a/3rdParty/Boost/src/boost/math/special_functions/sign.hpp b/3rdParty/Boost/src/boost/math/special_functions/sign.hpp index 6de88b2..f5c562d 100644 --- a/3rdParty/Boost/src/boost/math/special_functions/sign.hpp +++ b/3rdParty/Boost/src/boost/math/special_functions/sign.hpp @@ -31,7 +31,10 @@ namespace detail { } #endif - template<class T> + // Generic versions first, note that these do not handle + // signed zero or NaN. + + template<class T> inline int signbit_impl(T x, generic_tag<true> const&) { return x < 0; @@ -43,7 +46,25 @@ namespace detail { return x < 0; } - template<class T> +#if defined(__GNUC__) && (LDBL_MANT_DIG == 106) + // + // Special handling for GCC's "double double" type, + // in this case the sign is the same as the sign we + // get by casting to double, no overflow/underflow + // can occur since the exponents are the same magnitude + // for the two types: + // + inline int signbit_impl(long double x, generic_tag<true> const&) + { + return boost::math::signbit(static_cast<double>(x)); + } + inline int signbit_impl(long double x, generic_tag<false> const&) + { + return boost::math::signbit(static_cast<double>(x)); + } +#endif + + template<class T> inline int signbit_impl(T x, ieee_copy_all_bits_tag const&) { typedef BOOST_DEDUCED_TYPENAME fp_traits<T>::type traits; @@ -65,6 +86,9 @@ namespace detail { } // Changesign + + // Generic versions first, note that these do not handle + // signed zero or NaN. template<class T> inline T (changesign_impl)(T x, generic_tag<true> const&) @@ -77,7 +101,27 @@ namespace detail { { return -x; } - +#if defined(__GNUC__) && (LDBL_MANT_DIG == 106) + // + // Special handling for GCC's "double double" type, + // in this case we need to change the sign of both + // components of the "double double": + // + inline long double (changesign_impl)(long double x, generic_tag<true> const&) + { + double* pd = reinterpret_cast<double*>(&x); + pd[0] = boost::math::changesign(pd[0]); + pd[1] = boost::math::changesign(pd[1]); + return x; + } + inline long double (changesign_impl)(long double x, generic_tag<false> const&) + { + double* pd = reinterpret_cast<double*>(&x); + pd[0] = boost::math::changesign(pd[0]); + pd[1] = boost::math::changesign(pd[1]); + return x; + } +#endif template<class T> inline T changesign_impl(T x, ieee_copy_all_bits_tag const&) @@ -110,8 +154,9 @@ template<class T> int (signbit)(T x) { typedef typename detail::fp_traits<T>::type traits; typedef typename traits::method method; - typedef typename boost::is_floating_point<T>::type fp_tag; - return detail::signbit_impl(x, method()); + // typedef typename boost::is_floating_point<T>::type fp_tag; + typedef typename tools::promote_args_permissive<T>::type result_type; + return detail::signbit_impl(static_cast<result_type>(x), method()); } template <class T> @@ -120,20 +165,24 @@ inline int sign BOOST_NO_MACRO_EXPAND(const T& z) return (z == 0) ? 0 : (boost::math::signbit)(z) ? -1 : 1; } -template<class T> T (changesign)(const T& x) +template <class T> typename tools::promote_args_permissive<T>::type (changesign)(const T& x) { //!< \brief return unchanged binary pattern of x, except for change of sign bit. typedef typename detail::fp_traits<T>::sign_change_type traits; typedef typename traits::method method; - typedef typename boost::is_floating_point<T>::type fp_tag; + // typedef typename boost::is_floating_point<T>::type fp_tag; + typedef typename tools::promote_args_permissive<T>::type result_type; - return detail::changesign_impl(x, method()); + return detail::changesign_impl(static_cast<result_type>(x), method()); } -template <class T> -inline T copysign BOOST_NO_MACRO_EXPAND(const T& x, const T& y) +template <class T, class U> +inline typename tools::promote_args_permissive<T, U>::type + copysign BOOST_NO_MACRO_EXPAND(const T& x, const U& y) { BOOST_MATH_STD_USING - return (boost::math::signbit)(x) != (boost::math::signbit)(y) ? (boost::math::changesign)(x) : x; + typedef typename tools::promote_args_permissive<T, U>::type result_type; + return (boost::math::signbit)(static_cast<result_type>(x)) != (boost::math::signbit)(static_cast<result_type>(y)) + ? (boost::math::changesign)(static_cast<result_type>(x)) : static_cast<result_type>(x); } } // namespace math |