sysdeps/powerpc/powerpc32/e500/nofpu/fedisblxcpt.c

   1 /* Disable floating-point exceptions.  e500 version.
   2    Copyright (C) 2004-2014 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <fenv_libc.h>
  20 #include <sysdep.h>
  21 #include <sys/prctl.h>
  22
  23 int
  24 fedisableexcept (int excepts)
  25 {
  26   int result = 0, pflags, r;
  27   INTERNAL_SYSCALL_DECL (err);
  28
  29   r = INTERNAL_SYSCALL (prctl, err, 2, PR_GET_FPEXC, &pflags);
  30   if (INTERNAL_SYSCALL_ERROR_P (r, err))
  31     return -1;
  32
  33   /* Save old enable bits.  */
  34   result = __fexcepts_from_prctl (pflags);
  35
  36   pflags &= ~__fexcepts_to_prctl (excepts);
  37   r = INTERNAL_SYSCALL (prctl, err, 2, PR_SET_FPEXC,
  38                         pflags | PR_FP_EXC_SW_ENABLE);
  39   if (INTERNAL_SYSCALL_ERROR_P (r, err))
  40     return -1;
  41
  42   /* If disabling signals for "inexact", also disable trapping to the
  43      kernel.  */
  44   if ((excepts & FE_INEXACT) != 0)
  45     {
  46       unsigned long fpescr;
  47
  48       fpescr = fegetenv_register ();
  49       fpescr &= ~SPEFSCR_FINXE;
  50       fesetenv_register (fpescr);
  51     }
  52
  53   return result;
  54 }