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/* Store current floating-point environment and clear exceptions.
   Copyright (C) 1997, 1999, 2003 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 Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 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
   Lesser General Public License for more details.

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

#include <fenv.h>
#include <unistd.h>
#include <ldsodefs.h>
#include <dl-procinfo.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));

  /* If the CPU supports SSE we set the MXCSR as well.  */
  if ((GL(dl_hwcap) & HWCAP_I386_XMM) != 0)
    {
      unsigned int xwork;

      /* Get the current control word.  */
      __asm__ ("stmxcsr %0" : "=m" (*&xwork));

      /* Set all exceptions to non-stop.  */
      xwork |= 0x1f80;

      __asm__ ("ldmxcsr %0" : : "m" (*&xwork));
    }

  return 0;
}