sysdeps/ia64/fpu/fraiseexcpt.c

   1 /* Raise given exceptions.
   2    Copyright (C) 1997, 1998, 2000, 2001, 2002 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Jes Sorensen <Jes.Sorensen@cern.ch>, 2000.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 #include <fenv.h>
  22 #include <float.h>
  23 #include <math.h>
  24 #include <signal.h>
  25 #include <unistd.h>
  26
  27 int
  28 feraiseexcept (int excepts)
  29 {
  30   double tmp;
  31   double dummy;
  32
  33   /* Raise exceptions represented by EXPECTS.  But we must raise only
  34      one signal at a time.  It is important the if the overflow/underflow
  35      exception and the inexact exception are given at the same time,
  36      the overflow/underflow exception precedes the inexact exception.  */
  37
  38   /* We do these bits in assembly to be certain GCC doesn't optimize
  39      away something important.  */
  40
  41   /* First: invalid exception.  */
  42   if (FE_INVALID & excepts)
  43     {
  44       /* One example of a invalid operation is 0 * Infinity.  */
  45       tmp = 0;
  46       __asm__ __volatile__ ("frcpa.s0 %0,p1=f0,f0" : "=f" (tmp) : : "p1" );
  47     }
  48
  49   /* Next: division by zero.  */
  50   if (FE_DIVBYZERO & excepts)
  51     __asm__ __volatile__ ("frcpa.s0 %0,p1=f1,f0" : "=f" (tmp) : : "p1" );
  52
  53   /* Next: overflow.  */
  54   if (FE_OVERFLOW & excepts)
  55     {
  56       dummy = DBL_MAX;
  57
  58       __asm__ __volatile__ ("fadd.d.s0 %0=%1,%1" : "=f" (dummy) : "0" (dummy));
  59     }
  60
  61   /* Next: underflow.  */
  62   if (FE_UNDERFLOW & excepts)
  63     {
  64       dummy = DBL_MIN;
  65
  66       __asm__ __volatile__ ("fnma.d.s0 %0=%1,%1,f0" : "=f" (tmp) : "f" (dummy));
  67   }
  68
  69   /* Last: inexact.  */
  70   if (FE_INEXACT & excepts)
  71     {
  72       dummy = DBL_MAX;
  73       __asm__ __volatile__ ("fadd.d.s0 %0=%1,f1" : "=f" (dummy) : "0" (dummy));
  74     }
  75
  76   /* Success.  */
  77   return 0;
  78 }
  79 libm_hidden_def (feraiseexcept)