interval/detail/sparc_rounding_control.hpp

0001 /* Boost interval/detail/sparc_rounding_control.hpp file
0002  *
0003  * Copyright 2000 Jens Maurer
0004  * Copyright 2002 Hervé Brönnimann, Guillaume Melquiond, Sylvain Pion
0005  *
0006  * Distributed under the Boost Software License, Version 1.0.
0007  * (See accompanying file LICENSE_1_0.txt or
0008  * copy at http://www.boost.org/LICENSE_1_0.txt)
0009  *
0010  * The basic code in this file was kindly provided by Jeremy Siek.
0011  */
0012
0013 #ifndef BOOST_NUMERIC_INTERVAL_DETAIL_SPARC_ROUNDING_CONTROL_HPP
0014 #define BOOST_NUMERIC_INTERVAL_DETAIL_SPARC_ROUNDING_CONTROL_HPP
0015
0016 #if !defined(sparc) && !defined(__sparc__)
0017 #  error This header is only intended for SPARC CPUs.
0018 #endif
0019
0020 #ifdef __SUNPRO_CC
0021 #  include <ieeefp.h>
0022 #endif
0023
0024
0025 namespace boost {
0026 namespace numeric {
0027 namespace interval_lib {
0028 namespace detail {
0029
0030 struct sparc_rounding_control
0031 {
0032   typedef unsigned int rounding_mode;
0033
0034   static void set_rounding_mode(const rounding_mode& mode)
0035   {
0036 #   if defined(__GNUC__)
0037     __asm__ __volatile__("ld %0, %%fsr" : : "m"(mode));
0038 #   elif defined (__SUNPRO_CC)
0039     fpsetround(fp_rnd(mode));
0040 #   elif defined(__KCC)
0041     asm("sethi %hi(mode), %o1");
0042     asm("ld [%o1+%lo(mode)], %fsr");
0043 #   else
0044 #     error Unsupported compiler for Sparc rounding control.
0045 #   endif
0046   }
0047
0048   static void get_rounding_mode(rounding_mode& mode)
0049   {
0050 #   if defined(__GNUC__)
0051     __asm__ __volatile__("st %%fsr, %0" : "=m"(mode));
0052 #   elif defined (__SUNPRO_CC)
0053     mode = fpgetround();
0054 #   elif defined(__KCC)
0055 #     error KCC on Sun SPARC get_round_mode: please fix me
0056     asm("st %fsr, [mode]");
0057 #   else
0058 #     error Unsupported compiler for Sparc rounding control.
0059 #   endif
0060   }
0061
0062 #if defined(__SUNPRO_CC)
0063   static void downward()    { set_rounding_mode(FP_RM); }
0064   static void upward()      { set_rounding_mode(FP_RP); }
0065   static void to_nearest()  { set_rounding_mode(FP_RN); }
0066   static void toward_zero() { set_rounding_mode(FP_RZ); }
0067 #else
0068   static void downward()    { set_rounding_mode(0xc0000000); }
0069   static void upward()      { set_rounding_mode(0x80000000); }
0070   static void to_nearest()  { set_rounding_mode(0x00000000); }
0071   static void toward_zero() { set_rounding_mode(0x40000000); }
0072 #endif
0073 };
0074
0075 } // namespace detail
0076
0077 extern "C" {
0078   float rintf(float);
0079   double rint(double);
0080 }
0081
0082 template<>
0083 struct rounding_control<float>:
0084   detail::sparc_rounding_control
0085 {
0086   static const float& force_rounding(const float& x) { return x; }
0087   static float to_int(const float& x) { return rintf(x); }
0088 };
0089
0090 template<>
0091 struct rounding_control<double>:
0092   detail::sparc_rounding_control
0093 {
0094   static const double& force_rounding(const double& x) { return x; }
0095   static double to_int(const double& x) { return rint(x); }
0096 };
0097
0098 template<>
0099 struct rounding_control<long double>:
0100   detail::sparc_rounding_control
0101 {
0102   static const long double& force_rounding(const long double& x) { return x; }
0103   static long double to_int(const long double& x) { return rint(x); }
0104 };
0105
0106 } // namespace interval_lib
0107 } // namespace numeric
0108 } // namespace boost
0109
0110 #undef BOOST_NUMERIC_INTERVAL_NO_HARDWARE
0111
0112 #endif /* BOOST_NUMERIC_INTERVAL_DETAIL_SPARC_ROUNDING_CONTROL_HPP */