sysdeps/hppa/fpu/fesetround.c

   1 /* Set current rounding direction.
   2    Copyright (C) 2000-2023 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    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <fenv.h>
  20
  21 int
  22 __fesetround (int round)
  23 {
  24   union { unsigned long long l; unsigned int sw[2]; } s;
  25
  26   if (round & ~FE_DOWNWARD)
  27     /* round is not a valid rounding mode. */
  28     return 1;
  29
  30   /* Get the current status word. */
  31   __asm__ ("fstd %%fr0,0(%1)" : "=m" (s.l) : "r" (&s.l) : "%r0");
  32   s.sw[0] &= ~FE_DOWNWARD;
  33   s.sw[0] |= round & FE_DOWNWARD;
  34   __asm__ ("fldd 0(%0),%%fr0" : : "r" (&s.l), "m" (s.l) : "%r0");
  35
  36   return 0;
  37 }
  38
  39 libm_hidden_def (__fesetround)
  40 weak_alias (__fesetround, fesetround)
  41 libm_hidden_weak (fesetround)