ports/sysdeps/ia64/fpu/fraiseexcpt.c

   1 /* Raise given exceptions.
   2    Copyright (C) 1997-2014 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, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #include <fenv.h>
  21 #include <float.h>
  22 #include <math.h>
  23 #include <signal.h>
  24 #include <unistd.h>
  25
  26 int
  27 feraiseexcept (int excepts)
  28 {
  29   double tmp;
  30   double dummy;
  31
  32   /* Raise exceptions represented by EXPECTS.  But we must raise only
  33      one signal at a time.  It is important the if the overflow/underflow
  34      exception and the inexact exception are given at the same time,
  35      the overflow/underflow exception precedes the inexact exception.  */
  36
  37   /* We do these bits in assembly to be certain GCC doesn't optimize
  38      away something important.  */
  39
  40   /* First: invalid exception.  */
  41   if (FE_INVALID & excepts)
  42     {
  43       /* One example of an invalid operation is 0 * Infinity.  */
  44       tmp = 0;
  45       __asm__ __volatile__ ("frcpa.s0 %0,p1=f0,f0" : "=f" (tmp) : : "p1" );
  46     }
  47
  48   /* Next: division by zero.  */
  49   if (FE_DIVBYZERO & excepts)
  50     __asm__ __volatile__ ("frcpa.s0 %0,p1=f1,f0" : "=f" (tmp) : : "p1" );
  51
  52   /* Next: overflow.  */
  53   if (FE_OVERFLOW & excepts)
  54     {
  55       dummy = DBL_MAX;
  56
  57       __asm__ __volatile__ ("fadd.d.s0 %0=%1,%1" : "=f" (dummy) : "0" (dummy));
  58     }
  59
  60   /* Next: underflow.  */
  61   if (FE_UNDERFLOW & excepts)
  62     {
  63       dummy = DBL_MIN;
  64
  65       __asm__ __volatile__ ("fnma.d.s0 %0=%1,%1,f0" : "=f" (tmp) : "f" (dummy));
  66   }
  67
  68   /* Last: inexact.  */
  69   if (FE_INEXACT & excepts)
  70     {
  71       dummy = DBL_MAX;
  72       __asm__ __volatile__ ("fsub.d.s0 %0=%1,f1" : "=f" (dummy) : "0" (dummy));
  73     }
  74
  75   /* Success.  */
  76   return 0;
  77 }
  78 libm_hidden_def (feraiseexcept)