/* Enable floating-point exceptions.

   Copyright (C) 2001-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   Contributed by Philip Blundell <philb@gnu.org>, 2001.

   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, see

   <http://www.gnu.org/licenses/>.  */

#include <fenv.h>

#include <fpu_control.h>

#include <arm-features.h>

int

feenableexcept (int excepts)

{

  fpu_control_t fpscr, new_fpscr, updated_fpscr;

  /* Fail if a VFP unit isn't present.  */

  if (!ARM_HAVE_VFP)

    return -1;

  _FPU_GETCW (fpscr);

  excepts &= FE_ALL_EXCEPT;

  new_fpscr = fpscr | (excepts << FE_EXCEPT_SHIFT);

  if (new_fpscr != fpscr)

    {

      _FPU_SETCW (new_fpscr);

      /* Not all VFP architectures support trapping exceptions, so

	 test whether the relevant bits were set and fail if not.  */

      _FPU_GETCW (updated_fpscr);

      if (new_fpscr & ~updated_fpscr)

	return -1;

    }

  return (fpscr >> FE_EXCEPT_SHIFT) & FE_ALL_EXCEPT;

}