xref: /minix/lib/libc/arch/m68k/hardfloat/fpsetround.c (revision ebfedea0)
1 /*-
2  * Copyright (c) 2013 The NetBSD Foundation, Inc.
3  * All rights reserved.
4  *
5  * This code is derived from software contributed to The NetBSD Foundation
6  * by Matt Thomas of 3am Software Foundry.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
18  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
19  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
20  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
21  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27  * POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include "namespace.h"
31 
32 #include <ieeefp.h>
33 #include <m68k/fpreg.h>
34 
35 #ifdef __weak_alias
36 __weak_alias(fpsetround,_fpsetround)
37 #endif
38 
39 fp_rnd
40 _fpsetround(fp_rnd new)
41 {
42 	int old_fpcr, new_fpcr;
43 
44 	__asm("fmovel %%fpcr,%0" : "=d"(old_fpcr));
45 
46 	new_fpcr = (old_fpcr & ~FPCR_ROUND) | __SHIFTIN(new, FPCR_ROUND);
47 
48 	__asm("fmovel %0,%%fpcr" :: "d"(new_fpcr));
49 
50 	return __SHIFTOUT(old_fpcr, FPCR_ROUND);
51 }
52