xref: /openbsd/lib/libc/arch/aarch64/gen/fpsetsticky.c (revision 09467b48)
1 /*	$OpenBSD: fpsetsticky.c,v 1.1 2017/01/11 18:09:24 patrick Exp $	*/
2 /*
3  * Copyright (C) 2014 Andrew Turner
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  *
27  */
28 
29 #include <sys/cdefs.h>
30 
31 #include <sys/types.h>
32 #include <ieeefp.h>
33 
34 #ifdef __weak_alias
35 __weak_alias(_fpsetsticky,fpsetsticky);
36 #endif
37 
38 #define FP_X_MASK	(FP_X_INV | FP_X_DZ | FP_X_OFL | FP_X_UFL | FP_X_IMP)
39 
40 fp_except
41 fpsetsticky(fp_except except)
42 {
43 	fp_except old, new;
44 
45 	__asm __volatile("mrs %x0, fpcr" : "=&r"(old));
46 	new = old & ~(FP_X_MASK);
47 	new &= ~except;
48 	__asm __volatile("msr fpcr, %x0" : : "r"(new));
49 
50 	return (old & except);
51 }
52