ports/sysdeps/arm/fesetround.c

   1 /* Set current rounding direction.
   2    Copyright (C) 2004, 2005 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.h>
  20 #include <fpu_control.h>
  21
  22 #include <unistd.h>
  23 #include <ldsodefs.h>
  24 #include <dl-procinfo.h>
  25 #include <sysdep.h>
  26
  27 int
  28 fesetround (int round)
  29 {
  30   if (GLRO (dl_hwcap) & HWCAP_ARM_VFP)
  31     {
  32       fpu_control_t temp;
  33
  34       switch (round)
  35         {
  36         case FE_TONEAREST:
  37         case FE_UPWARD:
  38         case FE_DOWNWARD:
  39         case FE_TOWARDZERO:
  40           _FPU_GETCW (temp);
  41           temp = (temp & ~FE_TOWARDZERO) | round;
  42           _FPU_SETCW (temp);
  43           return 0;
  44         default:
  45           return 1;
  46         }
  47     }
  48   else if (round == FE_TONEAREST)
  49     /* This is the only supported rounding mode for soft-fp.  */
  50     return 0;
  51
  52   /* Unsupported, so fail.  */
  53   return 1;
  54 }
  55
  56 libm_hidden_def (fesetround)