fpsetround.c revision 1.1 
1/*	$NetBSD: fpsetround.c,v 1.1 2004/07/24 19:09:29 chs Exp $	*/
2
3/*	$OpenBSD: fpsetround.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/types.h>
10#include <ieeefp.h>
11
12fp_rnd
13fpsetround(fp_rnd rnd_dir)
14{
15	uint64_t fpsr;
16	fp_rnd old;
17
18	__asm__ __volatile__("fstd %%fr0,0(%1)" : "=m" (fpsr) : "r" (&fpsr));
19	old = (fpsr >> 41) & 0x03;
20	fpsr = (fpsr & 0xfffff9ff00000000LL) |
21	    ((uint64_t)(rnd_dir & 0x03) << 41);
22	__asm__ __volatile__("fldd 0(%0),%%fr0" : : "r" (&fpsr));
23	return (old);
24}
25