glibc/sysdeps/i386/fpu/feholdexcpt.c

/* Store current floating-point environment and clear exceptions.
   Copyright (C) 1997, 1999 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The GNU C Library 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <fenv.h>

int
feholdexcept (fenv_t *envp)
{
  unsigned short int work;

  /* Store the environment.  */
  __asm__ ("fnstenv %0" : "=m" (*envp));

  /* Now set all exceptions to non-stop.  */
  work = envp->__control_word | 0x3f;
  __asm__ ("fldcw %0" : : "m" (*&work));

  return 0;
}