Blame sysdeps/i386/fpu/fraiseexcpt.c

Packit 6c4009
/* Raise given exceptions.
Packit 6c4009
   Copyright (C) 1997-2018 Free Software Foundation, Inc.
Packit 6c4009
   This file is part of the GNU C Library.
Packit 6c4009
   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
Packit 6c4009
Packit 6c4009
   The GNU C Library is free software; you can redistribute it and/or
Packit 6c4009
   modify it under the terms of the GNU Lesser General Public
Packit 6c4009
   License as published by the Free Software Foundation; either
Packit 6c4009
   version 2.1 of the License, or (at your option) any later version.
Packit 6c4009
Packit 6c4009
   The GNU C Library is distributed in the hope that it will be useful,
Packit 6c4009
   but WITHOUT ANY WARRANTY; without even the implied warranty of
Packit 6c4009
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Packit 6c4009
   Lesser General Public License for more details.
Packit 6c4009
Packit 6c4009
   You should have received a copy of the GNU Lesser General Public
Packit 6c4009
   License along with the GNU C Library; if not, see
Packit 6c4009
   <http://www.gnu.org/licenses/>.  */
Packit 6c4009
Packit 6c4009
#include <fenv.h>
Packit 6c4009
#include <math.h>
Packit 6c4009
Packit 6c4009
int
Packit 6c4009
__feraiseexcept (int excepts)
Packit 6c4009
{
Packit 6c4009
  /* Raise exceptions represented by EXPECTS.  But we must raise only
Packit 6c4009
     one signal at a time.  It is important that if the overflow/underflow
Packit 6c4009
     exception and the inexact exception are given at the same time,
Packit 6c4009
     the overflow/underflow exception follows the inexact exception.  */
Packit 6c4009
Packit 6c4009
  /* First: invalid exception.  */
Packit 6c4009
  if ((FE_INVALID & excepts) != 0)
Packit 6c4009
    {
Packit 6c4009
      /* One example of an invalid operation is 0.0 / 0.0.  */
Packit 6c4009
      double d;
Packit 6c4009
      __asm__ __volatile__ ("fldz; fdiv %%st, %%st(0); fwait" : "=t" (d));
Packit 6c4009
      (void) &d;
Packit 6c4009
    }
Packit 6c4009
Packit 6c4009
  /* Next: division by zero.  */
Packit 6c4009
  if ((FE_DIVBYZERO & excepts) != 0)
Packit 6c4009
    {
Packit 6c4009
      double d;
Packit 6c4009
      __asm__ __volatile__ ("fldz; fld1; fdivp %%st, %%st(1); fwait"
Packit 6c4009
			    : "=t" (d));
Packit 6c4009
      (void) &d;
Packit 6c4009
    }
Packit 6c4009
Packit 6c4009
  /* Next: overflow.  */
Packit 6c4009
  if ((FE_OVERFLOW & excepts) != 0)
Packit 6c4009
    {
Packit 6c4009
      /* There is no way to raise only the overflow flag.  Do it the
Packit 6c4009
	 hard way.  */
Packit 6c4009
      fenv_t temp;
Packit 6c4009
Packit 6c4009
      /* Bah, we have to clear selected exceptions.  Since there is no
Packit 6c4009
	 `fldsw' instruction we have to do it the hard way.  */
Packit 6c4009
      __asm__ __volatile__ ("fnstenv %0" : "=m" (*&temp));
Packit 6c4009
Packit 6c4009
      /* Set the relevant bits.  */
Packit 6c4009
      temp.__status_word |= FE_OVERFLOW;
Packit 6c4009
Packit 6c4009
      /* Put the new data in effect.  */
Packit 6c4009
      __asm__ __volatile__ ("fldenv %0" : : "m" (*&temp));
Packit 6c4009
Packit 6c4009
      /* And raise the exception.  */
Packit 6c4009
      __asm__ __volatile__ ("fwait");
Packit 6c4009
    }
Packit 6c4009
Packit 6c4009
  /* Next: underflow.  */
Packit 6c4009
  if ((FE_UNDERFLOW & excepts) != 0)
Packit 6c4009
    {
Packit 6c4009
      /* There is no way to raise only the underflow flag.  Do it the
Packit 6c4009
	 hard way.  */
Packit 6c4009
      fenv_t temp;
Packit 6c4009
Packit 6c4009
      /* Bah, we have to clear selected exceptions.  Since there is no
Packit 6c4009
	 `fldsw' instruction we have to do it the hard way.  */
Packit 6c4009
      __asm__ __volatile__ ("fnstenv %0" : "=m" (*&temp));
Packit 6c4009
Packit 6c4009
      /* Set the relevant bits.  */
Packit 6c4009
      temp.__status_word |= FE_UNDERFLOW;
Packit 6c4009
Packit 6c4009
      /* Put the new data in effect.  */
Packit 6c4009
      __asm__ __volatile__ ("fldenv %0" : : "m" (*&temp));
Packit 6c4009
Packit 6c4009
      /* And raise the exception.  */
Packit 6c4009
      __asm__ __volatile__ ("fwait");
Packit 6c4009
    }
Packit 6c4009
Packit 6c4009
  /* Last: inexact.  */
Packit 6c4009
  if ((FE_INEXACT & excepts) != 0)
Packit 6c4009
    {
Packit 6c4009
      /* There is no way to raise only the inexact flag.  Do it the
Packit 6c4009
	 hard way.  */
Packit 6c4009
      fenv_t temp;
Packit 6c4009
Packit 6c4009
      /* Bah, we have to clear selected exceptions.  Since there is no
Packit 6c4009
	 `fldsw' instruction we have to do it the hard way.  */
Packit 6c4009
      __asm__ __volatile__ ("fnstenv %0" : "=m" (*&temp));
Packit 6c4009
Packit 6c4009
      /* Set the relevant bits.  */
Packit 6c4009
      temp.__status_word |= FE_INEXACT;
Packit 6c4009
Packit 6c4009
      /* Put the new data in effect.  */
Packit 6c4009
      __asm__ __volatile__ ("fldenv %0" : : "m" (*&temp));
Packit 6c4009
Packit 6c4009
      /* And raise the exception.  */
Packit 6c4009
      __asm__ __volatile__ ("fwait");
Packit 6c4009
    }
Packit 6c4009
Packit 6c4009
  /* Success.  */
Packit 6c4009
  return 0;
Packit 6c4009
}
Packit 6c4009
Packit 6c4009
#include <shlib-compat.h>
Packit 6c4009
#if SHLIB_COMPAT (libm, GLIBC_2_1, GLIBC_2_2)
Packit 6c4009
strong_alias (__feraiseexcept, __old_feraiseexcept)
Packit 6c4009
compat_symbol (libm, __old_feraiseexcept, feraiseexcept, GLIBC_2_1);
Packit 6c4009
#endif
Packit 6c4009
Packit 6c4009
libm_hidden_def (__feraiseexcept)
Packit 6c4009
libm_hidden_ver (__feraiseexcept, feraiseexcept)
Packit 6c4009
versioned_symbol (libm, __feraiseexcept, feraiseexcept, GLIBC_2_2);