1 /* $OpenBSD: fpsetsticky.c,v 1.5 2014/04/17 09:01:25 guenther Exp $ */
2 /* $NetBSD: fpsetsticky.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
fpsetsticky(mask)37 fpsetsticky(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 >> 25) & 0x1f;
45 fpscr = (fpscr & 0xe1ffffffULL) | ((mask & 0xf) << 25);
46 if (mask & FP_X_INV)
47 fpscr |= 0x400;
48 else
49 fpscr &= 0xfe07f8ffULL;
50 __asm__ volatile("mtfsf 0xff,%0" :: "f"(fpscr));
51 return (old);
52 }
53