xref: /netbsd-src/lib/libc/arch/sparc/gen/setjmp.S (revision 5e4c038a45edbc7d63b7c2daa76e29f88b64a4e3)
1/*	$NetBSD: setjmp.S,v 1.7 1998/09/29 05:55:49 christos Exp $	*/
2
3/*
4 * Copyright (c) 1992, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * This software was developed by the Computer Systems Engineering group
8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
9 * contributed to Berkeley.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 *    must display the following acknowledgement:
21 *	This product includes software developed by the University of
22 *	California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 *    may be used to endorse or promote products derived from this software
25 *    without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 *
39 * from: Header: setjmp.s,v 1.2 92/06/25 03:18:43 torek Exp
40 */
41
42#include <machine/asm.h>
43#if defined(LIBC_SCCS) && !defined(lint)
44#if 0
45	.asciz "@(#)setjmp.s	8.1 (Berkeley) 6/4/93"
46#else
47	RCSID("$NetBSD: setjmp.S,v 1.7 1998/09/29 05:55:49 christos Exp $")
48#endif
49#endif /* LIBC_SCCS and not lint */
50
51/*
52 * C library -- setjmp, longjmp
53 *
54 *	longjmp(a,v)
55 * will generate a "return(v)" from
56 * the last call to
57 *	setjmp(a)
58 * by restoring registers from the stack,
59 * and a struct sigcontext, see <signal.h>
60 */
61
62#include "SYS.h"
63
64ENTRY(setjmp)
65	/*
66	 * We use the caller's `arg dump' area (%sp+0x44; there are 6 ints
67	 * reserved there for us) to avoid having to allocate stack space
68	 * here.
69	 */
70	mov	%o0, %o2	/* build sigcontext in [%o2] */
71	mov	1, %o0		/* SIG_BLOCK */
72	mov	SYS_compat_13_sigprocmask13, %g1
73	clr	%o1		/* sigprocmask(SIG_BLOCK, (sigset_t *)NULL) */
74	t	ST_SYSCALL
75	st	%o0, [%o2 + 4]	/* sc.sc_mask = current mask; */
76	mov	SYS___sigaltstack14, %g1
77	clr	%o0		/* sigaltstack(NULL, &foo) */
78	add	%sp, 0x48, %o1	/* (foo being in arg dump area) */
79	t	ST_SYSCALL
80	ld	[%sp + 0x50], %o0	/* foo.ss_flags */
81	and	%o0, 1, %o1	/* onstack = foo.ss_flags & 1; */
82	st	%o0, [%o2 + 0]	/* sc.sc_onstack = current onstack; */
83	st	%sp, [%o2 + 8]	/* sc.sc_sp = sp (both ours and caller's) */
84	add	%o7, 8, %o0
85	st	%o0, [%o2 + 12]	/* sc.sc_pc = return_pc */
86	add	%o7, 12, %o0
87	st	%o0, [%o2 + 16]	/* sc.sc_npc = return_pc + 4 */
88	st	%g0, [%o2 + 20]	/* sc.sc_psr = (clean psr) */
89	st	%fp, [%o2 + 24]	/* sc.sc_g1 = %fp (misuse, but what the heck) */
90				/* sc.sc_o0 = random(), set in longjmp */
91	retl			/* return 0 */
92	 clr	%o0
93
94/*
95 * All we need to do here is force sigreturn to load a new stack pointer,
96 * new <pc,npc>, and appropriate %o0 return value from the sigcontext built
97 * in setjmp.  The %i and %l registers will be reloaded from the place to
98 * which %sp points, due to sigreturn() semantics (sigreturn does not modify
99 * the window pointer in the psr, hence it must force all windows to reload).
100 */
101ENTRY(longjmp)
102	save	%sp, -96, %sp
103	ld	[%i0 + 8], %o2	/* make sure sc->sc_sp, sc->sc_fp nonzero */
104	ld	[%i0 + 24], %o3
105	orcc	%o2, %o3, %g0
106	bz	Lbotch
107	 tst	%i1		/* if (v == 0) v = 1; */
108	bz,a	1f
109	 mov	1, %i1
1101:
111	st	%i1, [%i0 + 28]	/* sc.sc_o0 = v; */
112	mov	SYS_compat_13_sigreturn13, %g1
113	mov	%i0, %o0
114	t	ST_SYSCALL	/* sigreturn(scp); */
115
116Lbotch:
117	/* oops, caller botched it */
118	call	_C_LABEL(longjmperror)
119	 nop
120	unimp	0
121