xref: /illumos-gate/usr/src/cmd/dtrace/test/tst/sparc/ustack/tst.helper.c (revision 915894ef19890baaed00080f85f6b69e225cda98)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <stdint.h>
30 #include <stdlib.h>
31 #include <strings.h>
32 
33 int
34 baz(void)
35 {
36 	return (8);
37 }
38 
39 static int
40 foo(void)
41 {
42 	/*
43 	 * In order to assure that our helper is properly employed to identify
44 	 * the frame, we're going to trampoline through data.
45 	 */
46 	uint32_t instr[] = {
47 	    0x9de3bfa0,		/* save %sp, -0x60, %sp	*/
48 	    0x40000000,		/* call baz		*/
49 	    0x01000000,		/* nop			*/
50 	    0x81c7e008,		/* ret			*/
51 	    0x81e80000		/* restore		*/
52 	};
53 	uint32_t *fp = malloc(sizeof (instr));
54 
55 	/*
56 	 * Do our little relocation dance.
57 	 */
58 	instr[1] |= ((uintptr_t)baz - (uintptr_t)&fp[1]) >> 2;
59 
60 	/*
61 	 * Copy the code to the heap (it's a pain to build in ON with an
62 	 * executable stack).
63 	 */
64 	bcopy(instr, fp, sizeof (instr));
65 
66 	(*(int (*)(void))fp)();
67 
68 	free(fp);
69 
70 	return (0);
71 }
72 
73 int
74 main(int argc, char **argv)
75 {
76 	for (;;) {
77 		foo();
78 	}
79 
80 	return (0);
81 }
82