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

   1 /* Install given floating-point control modes.  e500 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 <sysdep.h>
  21 #include <sys/prctl.h>
  22
  23 #define SPEFSCR_STATUS 0xff3eff00
  24
  25 int
  26 fesetmode (const femode_t *modep)
  27 {
  28   fenv_union_t u;
  29   INTERNAL_SYSCALL_DECL (err);
  30   int r;
  31
  32   u.fenv = *modep;
  33   unsigned int spefscr = fegetenv_register ();
  34   spefscr = (spefscr & SPEFSCR_STATUS) | (u.l[1] & ~SPEFSCR_STATUS);
  35
  36   fesetenv_register (spefscr);
  37   r = INTERNAL_SYSCALL (prctl, err, 2, PR_SET_FPEXC,
  38                         u.l[0] | PR_FP_EXC_SW_ENABLE);
  39   if (INTERNAL_SYSCALL_ERROR_P (r, err))
  40     return -1;
  41
  42   return 0;
  43 }