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- /* 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
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