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

   This file is part of the GNU C Library.

   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>

int

feenableexcept (int excepts)

{

  fpu_control_t fpcr;

  fpu_control_t fpcr_new;

  fpu_control_t updated_fpcr;

  _FPU_GETCW (fpcr);

  excepts &= FE_ALL_EXCEPT;

  fpcr_new = fpcr | (excepts << FE_EXCEPT_SHIFT);

  if (fpcr != fpcr_new)

    {

      _FPU_SETCW (fpcr_new);

      /* Trapping exceptions are optional in AArch64; the relevant enable

	 bits in FPCR are RES0 hence the absence of support can be detected

	 by reading back the FPCR and comparing with the required value.  */

      _FPU_GETCW (updated_fpcr);

      if (fpcr_new & ~updated_fpcr)

	return -1;

    }

  return (fpcr >> FE_EXCEPT_SHIFT) & FE_ALL_EXCEPT;

}