xref: /openbsd/lib/libc/arch/powerpc64/gen/fpsetmask.c (revision 09467b48)
1 /*	$OpenBSD: fpsetmask.c,v 1.1 2020/06/25 02:03:55 drahn Exp $	*/
2 /*	$NetBSD: fpsetmask.c,v 1.1 1999/07/07 01:55:08 danw Exp $	*/
3 
4 /*
5  * Copyright (c) 1999 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Dan Winship.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/types.h>
34 #include <ieeefp.h>
35 
36 fp_except
37 fpsetmask(mask)
38 	fp_except mask;
39 {
40 	u_int64_t fpscr;
41 	fp_rnd old;
42 
43 	__asm__ volatile("mffs %0" : "=f"(fpscr));
44 	old = (fpscr >> 3) & 0x1f;
45 	fpscr = (fpscr & 0xffffff07ULL) | (mask << 3);
46 	__asm__ volatile("mtfsf 0xff,%0" :: "f"(fpscr));
47 	return (old);
48 }
49