xref: /openbsd/lib/libc/arch/sparc64/sys/tfork_thread.S (revision 09467b48)
1/*	$OpenBSD: tfork_thread.S,v 1.3 2015/09/05 06:22:47 guenther Exp $	*/
2
3/*
4 * Copyright (c) 2005, Miodrag Vallat
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 ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18 * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
19 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
20 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
23 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
24 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25 * POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#include "SYS.h"
29
30/*
31 * int __tfork_thread(const struct __tfork *param, size_t psize, void (*func)(void *), void *arg);
32 */
33ENTRY(__tfork_thread)
34	/*
35	 * We can not invoke __tfork as a G2-style system call since we want
36	 * different return paths.
37	 */
38	mov	SYS___tfork, %g1
39	t	ST_SYSCALL
40	bcs	9f
41	 nop
42
43	cmp	%o0, 0
44	be	1f
45	 nop
46
47	/*
48	 * In parent process: just return.
49	 */
50	retl
51	 nop
52
531:
54	/*
55	 * In child process: invoke function, then exit.
56	 */
57	call	%o2				/* func */
58	 mov	%o3, %o0			/* arg */
59
60	mov	SYS___threxit, %g1
61	clr	%o0
62	t	ST_SYSCALL	/* will not return */
63
649:
65	/*
66	 * System call failure.
67	 */
68	ERROR()
69END(__tfork_thread)
70