lib/libc/arch/hppa/gen/flt_rounds.c

   1 /*      $NetBSD: flt_rounds.c,v 1.5 2012/03/23 09:34:09 skrll Exp $     */
   2
   3 /*      $OpenBSD: flt_rounds.c,v 1.3 2002/10/21 18:41:05 mickey Exp $   */
   4
   5 /*
   6  * Written by Miodrag Vallat.  Public domain.
   7  */
   8
   9 #include <sys/cdefs.h>
  10 #if defined(LIBC_SCCS) && !defined(lint)
  11 __RCSID("$NetBSD: flt_rounds.c,v 1.5 2012/03/23 09:34:09 skrll Exp $");
  12 #endif /* LIBC_SCCS and not lint */
  13
  14 #include <sys/types.h>
  15 #include <machine/float.h>
  16
  17 static const int map[] = {
  18         1,      /* round to nearest */
  19         0,      /* round to zero */
  20         2,      /* round to positive infinity */
  21         3       /* round to negative infinity */
  22 };
  23
  24 int
  25 __flt_rounds(void)
  26 {
  27         uint64_t fpsr;
  28
  29         __asm volatile("fstd %%fr0,0(%1)" : "=m" (fpsr) : "r" (&fpsr));
  30         return map[(unsigned int)(fpsr >> 41) & 0x03];
  31 }