/* 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 |