diff options
Diffstat (limited to 'boost/multiprecision/cpp_bin_float.hpp')
| -rw-r--r-- | boost/multiprecision/cpp_bin_float.hpp | 89 |
1 files changed, 63 insertions, 26 deletions
diff --git a/boost/multiprecision/cpp_bin_float.hpp b/boost/multiprecision/cpp_bin_float.hpp index 453a406f28..38f5387528 100644 --- a/boost/multiprecision/cpp_bin_float.hpp +++ b/boost/multiprecision/cpp_bin_float.hpp @@ -11,6 +11,16 @@ #include <boost/math/special_functions/trunc.hpp> #include <boost/multiprecision/detail/float_string_cvt.hpp> +// +// Some includes we need from Boost.Math, since we rely on that library to provide these functions: +// +#include <boost/math/special_functions/asinh.hpp> +#include <boost/math/special_functions/acosh.hpp> +#include <boost/math/special_functions/atanh.hpp> +#include <boost/math/special_functions/cbrt.hpp> +#include <boost/math/special_functions/expm1.hpp> +#include <boost/math/special_functions/gamma.hpp> + namespace boost{ namespace multiprecision{ namespace backends{ enum digit_base_type @@ -67,7 +77,7 @@ private: exponent_type m_exponent; bool m_sign; public: - cpp_bin_float() BOOST_MP_NOEXCEPT_IF(noexcept(rep_type())) : m_data(), m_exponent(exponent_nan), m_sign(false) {} + cpp_bin_float() BOOST_MP_NOEXCEPT_IF(noexcept(rep_type())) : m_data(), m_exponent(exponent_zero), m_sign(false) {} cpp_bin_float(const cpp_bin_float &o) BOOST_MP_NOEXCEPT_IF(noexcept(rep_type(std::declval<const rep_type&>()))) : m_data(o.m_data), m_exponent(o.m_exponent), m_sign(o.m_sign) {} @@ -574,7 +584,9 @@ inline void do_eval_subtract(cpp_bin_float<Digits, DigitBase, Allocator, Exponen { bool s = a.sign(); res = b; - if(res.sign() == s) + if(res.exponent() == cpp_bin_float<Digits, DigitBase, Allocator, Exponent, MinE, MaxE>::exponent_zero) + res.sign() = false; + else if(res.sign() == s) res.negate(); } return; @@ -633,7 +645,9 @@ inline void do_eval_subtract(cpp_bin_float<Digits, DigitBase, Allocator, Exponen } copy_and_round(res, dt); - if(res.sign() != s) + if(res.exponent() == cpp_bin_float<Digits, DigitBase, Allocator, Exponent, MinE, MaxE>::exponent_zero) + res.sign() = false; + else if(res.sign() != s) res.negate(); res.check_invariants(); } @@ -1221,7 +1235,8 @@ inline typename boost::enable_if_c<boost::is_float<Float>::value>::type eval_con // // Perform rounding first, then afterwards extract the digits: // - typedef cpp_bin_float<std::numeric_limits<Float>::digits, digit_base_2, void, Exponent, MinE, MaxE> conv_type; + typedef cpp_bin_float<std::numeric_limits<Float>::digits, digit_base_2, void, Exponent, MinE, MaxE> conv_type; + typedef typename common_type<typename conv_type::exponent_type, int>::type common_exp_type; conv_type arg(original_arg); switch(arg.exponent()) { @@ -1239,13 +1254,26 @@ inline typename boost::enable_if_c<boost::is_float<Float>::value>::type eval_con *res = -*res; return; } - typename conv_type::exponent_type e = arg.exponent(); + common_exp_type e = arg.exponent(); + static const common_exp_type min_exp_limit = std::numeric_limits<Float>::min_exponent + - (common_exp_type)cpp_bin_float<std::numeric_limits<Float>::digits, digit_base_2, void, Exponent, MinE, MaxE>::bit_count - std::numeric_limits<Float>::digits - 2; e -= cpp_bin_float<std::numeric_limits<Float>::digits, digit_base_2, void, Exponent, MinE, MaxE>::bit_count - 1; - *res = std::ldexp(static_cast<Float>(*arg.bits().limbs()), e); + if(e < min_exp_limit) + { + *res = 0; + return; + } + if(e > std::numeric_limits<Float>::max_exponent) + { + *res = std::numeric_limits<Float>::has_infinity ? std::numeric_limits<Float>::infinity() : (std::numeric_limits<Float>::max)(); + return; + } + + *res = std::ldexp(static_cast<Float>(*arg.bits().limbs()), static_cast<int>(e)); for(unsigned i = 1; i < arg.bits().size(); ++i) { e += sizeof(*arg.bits().limbs()) * CHAR_BIT; - *res += std::ldexp(static_cast<Float>(arg.bits().limbs()[i]), e); + *res += std::ldexp(static_cast<Float>(arg.bits().limbs()[i]), static_cast<int>(e)); } if(arg.sign()) *res = -*res; @@ -1471,7 +1499,9 @@ inline void eval_ceil(cpp_bin_float<Digits, DigitBase, Allocator, Exponent, MinE } if(shift >= (int)cpp_bin_float<Digits, DigitBase, Allocator, Exponent, MinE, MaxE>::bit_count) { + bool s = arg.sign(); // takes care of signed zeros res = static_cast<signed_limb_type>(arg.sign() ? 0 : 1); + res.sign() = s; return; } bool fractional = (int)eval_lsb(arg.bits()) < shift; @@ -1514,6 +1544,22 @@ struct is_explicitly_convertible<FloatT, backends::cpp_bin_float<D2, B2, A2, E2, } #endif +template<unsigned Digits, boost::multiprecision::backends::digit_base_type DigitBase, class Exponent, Exponent MinE, Exponent MaxE, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates> +inline int signbit BOOST_PREVENT_MACRO_SUBSTITUTION(const boost::multiprecision::number<boost::multiprecision::backends::cpp_bin_float<Digits, DigitBase, Allocator, Exponent, MinE, MaxE>, ExpressionTemplates>& arg) +{ + return arg.backend().sign(); +} + +template<unsigned Digits, boost::multiprecision::backends::digit_base_type DigitBase, class Exponent, Exponent MinE, Exponent MaxE, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates> +inline boost::multiprecision::number<boost::multiprecision::backends::cpp_bin_float<Digits, DigitBase, Allocator, Exponent, MinE, MaxE>, ExpressionTemplates> +copysign BOOST_PREVENT_MACRO_SUBSTITUTION( + const boost::multiprecision::number<boost::multiprecision::backends::cpp_bin_float<Digits, DigitBase, Allocator, Exponent, MinE, MaxE>, ExpressionTemplates>& a, + const boost::multiprecision::number<boost::multiprecision::backends::cpp_bin_float<Digits, DigitBase, Allocator, Exponent, MinE, MaxE>, ExpressionTemplates>& b) +{ + boost::multiprecision::number<boost::multiprecision::backends::cpp_bin_float<Digits, DigitBase, Allocator, Exponent, MinE, MaxE>, ExpressionTemplates> res(a); + res.backend().sign() = b.backend().sign(); + return res; +} using backends::cpp_bin_float; using backends::digit_base_2; @@ -1540,23 +1586,8 @@ typedef number<backends::cpp_bin_float<113, backends::digit_base_2, void, boost: namespace math { - template<unsigned Digits, boost::multiprecision::backends::digit_base_type DigitBase, class Exponent, Exponent MinE, Exponent MaxE, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates> - inline int signbit BOOST_PREVENT_MACRO_SUBSTITUTION(const boost::multiprecision::number<boost::multiprecision::backends::cpp_bin_float<Digits, DigitBase, Allocator, Exponent, MinE, MaxE>, ExpressionTemplates>& arg) - { - return arg.backend().sign(); - } - - template<unsigned Digits, boost::multiprecision::backends::digit_base_type DigitBase, class Exponent, Exponent MinE, Exponent MaxE, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates> - inline boost::multiprecision::number<boost::multiprecision::backends::cpp_bin_float<Digits, DigitBase, Allocator, Exponent, MinE, MaxE>, ExpressionTemplates> - copysign BOOST_PREVENT_MACRO_SUBSTITUTION( - const boost::multiprecision::number<boost::multiprecision::backends::cpp_bin_float<Digits, DigitBase, Allocator, Exponent, MinE, MaxE>, ExpressionTemplates>& a, - const boost::multiprecision::number<boost::multiprecision::backends::cpp_bin_float<Digits, DigitBase, Allocator, Exponent, MinE, MaxE>, ExpressionTemplates>& b) - { - boost::multiprecision::number<boost::multiprecision::backends::cpp_bin_float<Digits, DigitBase, Allocator, Exponent, MinE, MaxE>, ExpressionTemplates> res(a); - res.backend().sign() = b.backend().sign(); - return res; - } - + using boost::multiprecision::signbit; + using boost::multiprecision::copysign; } // namespace math @@ -1649,7 +1680,6 @@ public: BOOST_STATIC_CONSTEXPR bool has_denorm_loss = false; static number_type infinity() { - // returns epsilon/2 initializer.do_nothing(); static std::pair<bool, number_type> value; if(!value.first) @@ -1661,7 +1691,14 @@ public: } static number_type quiet_NaN() { - return number_type(); + initializer.do_nothing(); + static std::pair<bool, number_type> value; + if(!value.first) + { + value.first = true; + value.second.backend().exponent() = boost::multiprecision::cpp_bin_float<Digits, DigitBase, Allocator, Exponent, MinE, MaxE>::exponent_nan; + } + return value.second; } BOOST_STATIC_CONSTEXPR number_type signaling_NaN() { |