gcc/libgcc/config/rs6000/sfp-exceptions.c

/* Copyright (C) 2016 Free Software Foundation, Inc.

   This file is free software; you can redistribute it and/or modify it
   under the terms of the GNU General Public License as published by the
   Free Software Foundation; either version 3, or (at your option) any
   later version.

   This file is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.

   Under Section 7 of GPL version 3, you are granted additional
   permissions described in the GCC Runtime Library Exception, version
   3.1, as published by the Free Software Foundation.

   You should have received a copy of the GNU General Public License and
   a copy of the GCC Runtime Library Exception along with this program;
   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
   <http://www.gnu.org/licenses/>.  */

#include "sfp-machine.h"

/* Only provide exception support if we have hardware floating point and we can
   execute the mtfsf instruction.  This would only be true if we are using the
   emulation routines for IEEE 128-bit floating point on pre-ISA 3.0 machines
   without the IEEE 128-bit floating point support.  */

#ifndef __NO_FPRS__ 

void
__sfp_handle_exceptions (int _fex)
{
  const double fp_max = __DBL_MAX__;
  const double fp_min = __DBL_MIN__;
  const double fp_zero = (double) 0.0;
  const double fp_one = 1.0;
  double tmp;

  if (_fex & FP_EX_INVALID)
    {
      __asm__ __volatile__ ("fdiv %0, %1, %1"
			    : "=f" (tmp)
			    : "f" (fp_zero));
    }
  if (_fex & FP_EX_DIVZERO)
    {
      __asm__ __volatile__ ("fdiv %0, %1, %2"
			    : "=f" (tmp)
			    : "f" (fp_one), "f" (fp_zero));
    }
  if (_fex & FP_EX_OVERFLOW)
    {
      __asm__ __volatile__ ("fadd %0, %1, %1"
			    : "=f" (tmp)
			    : "f" (fp_max));
    }
  if (_fex & FP_EX_UNDERFLOW)
    {
      __asm__ __volatile__ ("fmul %0, %1, %1"
			    : "=f" (tmp)
			    : "f" (fp_min));
    }
  if (_fex & FP_EX_INEXACT)
    {
      __asm__ __volatile__ ("fsub %0, %1, %2"
			    : "=f" (tmp)
			    : "f" (fp_max), "f" (fp_one));
    }
}

#endif	/* !__NO_FPRS__   */