| /* Boost interval/detail/x86gcc_rounding_control.hpp file |
| * |
| * This header provides a rounding control policy |
| * that avoids flushing results to memory. In |
| * order for this optimization to be reliable, it |
| * should be used only when no underflow or |
| * overflow would happen without it. Indeed, only |
| * values in range are correctly rounded. |
| * |
| * Copyright 2002 Hervé Brönnimann, Guillaume Melquiond, Sylvain Pion |
| * |
| * 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 BOOST_NUMERIC_INTERVAL_EXT_X86_FAST_ROUNDING_CONTROL_HPP |
| #define BOOST_NUMERIC_INTERVAL_EXT_X86_FAST_ROUNDING_CONTROL_HPP |
| |
| namespace boost { |
| namespace numeric { |
| namespace interval_lib { |
| |
| namespace detail { |
| |
| // exceptions masked, expected precision (the mask is 0x0300) |
| static const fpu_rounding_modes rnd_mode_f = { 0x107f, 0x147f, 0x187f, 0x1c7f }; |
| static const fpu_rounding_modes rnd_mode_d = { 0x127f, 0x167f, 0x1a7f, 0x1e7f }; |
| static const fpu_rounding_modes rnd_mode_l = { 0x137f, 0x177f, 0x1b7f, 0x1f7f }; |
| |
| } // namespace detail |
| |
| template<class T> |
| struct x86_fast_rounding_control; |
| |
| template<> |
| struct x86_fast_rounding_control<float>: detail::x86_rounding |
| { |
| static void to_nearest() { set_rounding_mode(detail::rnd_mode_f.to_nearest); } |
| static void downward() { set_rounding_mode(detail::rnd_mode_f.downward); } |
| static void upward() { set_rounding_mode(detail::rnd_mode_f.upward); } |
| static void toward_zero() { set_rounding_mode(detail::rnd_mode_f.toward_zero); } |
| static const float& force_rounding(const float& r) { return r; } |
| }; |
| |
| template<> |
| struct x86_fast_rounding_control<double>: detail::x86_rounding |
| { |
| static void to_nearest() { set_rounding_mode(detail::rnd_mode_d.to_nearest); } |
| static void downward() { set_rounding_mode(detail::rnd_mode_d.downward); } |
| static void upward() { set_rounding_mode(detail::rnd_mode_d.upward); } |
| static void toward_zero() { set_rounding_mode(detail::rnd_mode_d.toward_zero); } |
| static const double& force_rounding(const double& r) { return r; } |
| }; |
| |
| template<> |
| struct x86_fast_rounding_control<long double>: detail::x86_rounding |
| { |
| static void to_nearest() { set_rounding_mode(detail::rnd_mode_l.to_nearest); } |
| static void downward() { set_rounding_mode(detail::rnd_mode_l.downward); } |
| static void upward() { set_rounding_mode(detail::rnd_mode_l.upward); } |
| static void toward_zero() { set_rounding_mode(detail::rnd_mode_l.toward_zero); } |
| static const long double& force_rounding(const long double& r) { return r; } |
| }; |
| |
| } // namespace interval_lib |
| } // namespace numeric |
| } // namespace boost |
| |
| #endif // BOOST_NUMERIC_INTERVAL_EXT_X86_FAST_ROUNDING_CONTROL_HPP |