sysdeps/powerpc/fpu/fesetmode.c

   1 /* Install given floating-point control modes.  PowerPC version.
   2    Copyright (C) 2016-2018 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 <fpu_control.h>
  21
  22 #define _FPU_MASK_ALL (_FPU_MASK_ZM | _FPU_MASK_OM | _FPU_MASK_UM       \
  23                        | _FPU_MASK_XM | _FPU_MASK_IM)
  24
  25 #define FPU_STATUS 0xbffff700ULL
  26
  27 int
  28 fesetmode (const femode_t *modep)
  29 {
  30   fenv_union_t old, new;
  31
  32   /* Logic regarding enabled exceptions as in fesetenv.  */
  33
  34   new.fenv = *modep;
  35   old.fenv = fegetenv_register ();
  36   new.l = (new.l & ~FPU_STATUS) | (old.l & FPU_STATUS);
  37
  38   if (old.l == new.l)
  39     return 0;
  40
  41   if ((old.l & _FPU_MASK_ALL) == 0 && (new.l & _FPU_MASK_ALL) != 0)
  42     (void) __fe_nomask_env_priv ();
  43
  44   if ((old.l & _FPU_MASK_ALL) != 0 && (new.l & _FPU_MASK_ALL) == 0)
  45     (void) __fe_mask_env ();
  46
  47   fesetenv_register (new.fenv);
  48   return 0;
  49 }