/* 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 */ |