| /* Boost interval/detail/ppc_rounding_control.hpp file |
| * |
| * Copyright 2000 Jens Maurer |
| * Copyright 2002 Hervé Brönnimann, Guillaume Melquiond, Sylvain Pion |
| * Copyright 2005 Guillaume Melquiond |
| * |
| * 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_DETAIL_PPC_ROUNDING_CONTROL_HPP |
| #define BOOST_NUMERIC_INTERVAL_DETAIL_PPC_ROUNDING_CONTROL_HPP |
| |
| #if !defined(powerpc) && !defined(__powerpc__) && !defined(__ppc__) |
| #error This header only works on PPC CPUs. |
| #endif |
| |
| #if defined(__GNUC__ ) || (__IBMCPP__ >= 700) |
| |
| namespace boost { |
| namespace numeric { |
| namespace interval_lib { |
| namespace detail { |
| |
| typedef union { |
| ::boost::long_long_type imode; |
| double dmode; |
| } rounding_mode_struct; |
| |
| static const rounding_mode_struct mode_upward = { 0xFFF8000000000002LL }; |
| static const rounding_mode_struct mode_downward = { 0xFFF8000000000003LL }; |
| static const rounding_mode_struct mode_to_nearest = { 0xFFF8000000000000LL }; |
| static const rounding_mode_struct mode_toward_zero = { 0xFFF8000000000001LL }; |
| |
| struct ppc_rounding_control |
| { |
| typedef double rounding_mode; |
| |
| static void set_rounding_mode(const rounding_mode mode) |
| { __asm__ __volatile__ ("mtfsf 255,%0" : : "f"(mode)); } |
| |
| static void get_rounding_mode(rounding_mode& mode) |
| { __asm__ __volatile__ ("mffs %0" : "=f"(mode)); } |
| |
| static void downward() { set_rounding_mode(mode_downward.dmode); } |
| static void upward() { set_rounding_mode(mode_upward.dmode); } |
| static void to_nearest() { set_rounding_mode(mode_to_nearest.dmode); } |
| static void toward_zero() { set_rounding_mode(mode_toward_zero.dmode); } |
| }; |
| |
| } // namespace detail |
| |
| // Do not declare the following C99 symbols if <math.h> provides them. |
| // Otherwise, conflicts may occur, due to differences between prototypes. |
| #if !defined(_ISOC99_SOURCE) && !defined(__USE_ISOC99) |
| extern "C" { |
| float rintf(float); |
| double rint(double); |
| } |
| #endif |
| |
| template<> |
| struct rounding_control<float>: |
| detail::ppc_rounding_control |
| { |
| static float force_rounding(const float r) |
| { |
| float tmp; |
| __asm__ __volatile__ ("frsp %0, %1" : "=f" (tmp) : "f" (r)); |
| return tmp; |
| } |
| static float to_int(const float& x) { return rintf(x); } |
| }; |
| |
| template<> |
| struct rounding_control<double>: |
| detail::ppc_rounding_control |
| { |
| static const double & force_rounding(const double& r) { return r; } |
| static double to_int(const double& r) { return rint(r); } |
| }; |
| |
| template<> |
| struct rounding_control<long double>: |
| detail::ppc_rounding_control |
| { |
| static const long double & force_rounding(const long double& r) { return r; } |
| static long double to_int(const long double& r) { return rint(r); } |
| }; |
| |
| } // namespace interval_lib |
| } // namespace numeric |
| } // namespace boost |
| |
| #undef BOOST_NUMERIC_INTERVAL_NO_HARDWARE |
| #endif |
| |
| #endif /* BOOST_NUMERIC_INTERVAL_DETAIL_PPC_ROUNDING_CONTROL_HPP */ |