sysdeps/powerpc/fsetexcptflg.c

   1 /* Set floating-point environment exception handling.
   2    Copyright (C) 1997 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 Library General Public License as
   7    published by the Free Software Foundation; either version 2 of the
   8    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    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.  */
  19
  20 #include <fenv_libc.h>
  21
  22 void
  23 fesetexceptflag (const fexcept_t *flagp, int excepts)
  24 {
  25   fenv_union_t u;
  26   fexcept_t flag;
  27
  28   /* Get the current state.  */
  29   u.fenv = fegetenv_register ();
  30
  31   /* Ignore exceptions not listed in 'excepts'.  */
  32   flag = *flagp & excepts;
  33
  34   /* Replace the exception status */
  35   u.l[1] = ((u.l[1] & ~(FPSCR_STICKY_BITS & excepts))
  36             | (flag & FPSCR_STICKY_BITS)
  37             | (flag >> ((31 - FPSCR_VX) - (31 - FPSCR_VXSOFT))
  38                & FE_INVALID_SOFTWARE));
  39
  40   /* Store the new status word (along with the rest of the environment).
  41      This may cause floating-point exceptions if the restored state
  42      requests it.  */
  43   fesetenv_register (u.fenv);
  44
  45   /* Deal with FE_INVALID_SOFTWARE not being implemented on some chips.  */
  46   if (flag & FE_INVALID)
  47     feraiseexcept(FE_INVALID);
  48 }