xref: /openbsd-src/regress/sys/arch/amd64/fpu/fdump.c (revision 49a6e16f2c2c8e509184b1f777366d1a6f337e1c)
1 /*	$OpenBSD: fdump.c,v 1.2 2021/12/13 16:56:49 deraadt Exp $	*/
2 /*
3  * Copyright (c) 2018 Alexander Bluhm <bluhm@openbsd.org>
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 and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include <sys/types.h>
19 
20 #include <err.h>
21 #include <fenv.h>
22 #include <stdio.h>
23 #include <unistd.h>
24 
25 #define nitems(_a)     (sizeof((_a)) / sizeof((_a)[0]))
26 
27 int
main(int argc,char * argv[])28 main(int argc, char *argv[])
29 {
30 	struct {
31 		fenv_t	fenv;
32 		/* Try to read more and check env length. */
33 		char	pad[1];
34 	} buf;
35 	fenv_t *fenv = &buf.fenv;
36 	ssize_t len;
37 	size_t i;
38 
39 	len = read(0, &buf, sizeof(buf));
40 	if (len < 0 )
41 		err(1, "read");
42 	if (len != sizeof(fenv_t))
43 		errx(1, "read len %zd is not size %zu", len, sizeof(fenv_t));
44 
45 	printf("control\t%08x\n", fenv->__x87.__control);
46 	printf("status\t%08x\n", fenv->__x87.__status);
47 	printf("tag\t%08x\n", fenv->__x87.__tag);
48 	for (i = 0; i < nitems(fenv->__x87.__others); i++) {
49 		printf("others[%zu]\t%08x\n", i, fenv->__x87.__others[i]);
50 	}
51 	printf("mxcsr\t%08x\n", fenv->__mxcsr);
52 
53 	return 0;
54 }
55