xref: /openbsd/lib/libc/arch/sh/gen/flt_rounds.c (revision 404b540a)
1 /*	$OpenBSD: flt_rounds.c,v 1.2 2006/11/14 09:51:25 otto Exp $	*/
2 /*
3  * Copyright (c) 2006 Miodrag Vallat.
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice, this permission notice, and the disclaimer below
8  * appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/types.h>
20 #include <machine/float.h>
21 #include <machine/ieeefp.h>
22 
23 static const int rndmap[] = {
24 	1,	/* round to nearest */
25 	0,	/* round to zero */
26 	2,	/* round to positive infinity */
27 	3	/* round to negative infinity */
28 };
29 
30 int
31 __flt_rounds()
32 {
33 #if !defined(SOFTFLOAT)
34 	register_t fpscr;
35 
36 	__asm__ __volatile__ ("sts fpscr, %0" : "=r" (fpscr));
37 	return rndmap[fpscr & 0x03];
38 #else
39 	return rndmap[fpgetround()];
40 #endif
41 }
42