xref: /csrg-svn/lib/libc/sparc/gen/_setjmp.s (revision 54385)
1*54385Storek/*
2*54385Storek * Copyright (c) 1992 The Regents of the University of California.
3*54385Storek * All rights reserved.
4*54385Storek *
5*54385Storek * This software was developed by the Computer Systems Engineering group
6*54385Storek * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
7*54385Storek * contributed to Berkeley.
8*54385Storek *
9*54385Storek * %sccs.include.redist.c%
10*54385Storek *
11*54385Storek * from: $Header: _setjmp.s,v 1.1 91/07/06 16:45:53 torek Exp $
12*54385Storek */
13*54385Storek
14*54385Storek#if defined(LIBC_SCCS) && !defined(lint)
15*54385Storek	.asciz "@(#)_setjmp.s	5.1 (Berkeley) 06/25/92"
16*54385Storek#endif /* LIBC_SCCS and not lint */
17*54385Storek
18*54385Storek/*
19*54385Storek * C library -- _setjmp, _longjmp
20*54385Storek *
21*54385Storek *	_longjmp(a,v)
22*54385Storek * will generate a "return(v?v:1)" from
23*54385Storek * the last call to
24*54385Storek *	_setjmp(a)
25*54385Storek * by unwinding the call stack.
26*54385Storek * The previous signal state is NOT restored.
27*54385Storek */
28*54385Storek
29*54385Storek#include "DEFS.h"
30*54385Storek
31*54385StorekENTRY(_setjmp)
32*54385Storek	std	%sp, [%o0+0]	/* caller's stack pointer and return pc */
33*54385Storek	st	%fp, [%o0+8]	/* store caller's frame pointer */
34*54385Storek	retl
35*54385Storek	 clr	%o0		! return 0
36*54385Storek
37*54385StorekENTRY(_longjmp)
38*54385Storek	addcc	%o1, %g0, %g6	! compute v ? v : 1 in a global register
39*54385Storek	be,a	0f
40*54385Storek	 mov	1, %g6
41*54385Storek0:
42*54385Storek	mov	%o0, %g1	! save a in another global register
43*54385Storek	ld	[%g1+8], %g7	/* get caller's frame */
44*54385Storek1:
45*54385Storek	cmp	%fp, %g7	! compare against desired frame
46*54385Storek	bl,a	1b		! if below,
47*54385Storek	 restore		!    pop frame and loop
48*54385Storek	be,a	2f		! if there,
49*54385Storek	 ldd	[%g1+0], %o2	!    fetch return %sp and pc, and get out
50*54385Storek
51*54385StorekLbotch:
52*54385Storek	call	_longjmperror	! otherwise, went too far; bomb out
53*54385Storek	nop
54*54385Storek	unimp	0
55*54385Storek
56*54385Storek2:
57*54385Storek	cmp	%o2, %sp	! %sp must not decrease
58*54385Storek	bge,a	3f
59*54385Storek	 mov	%o2, %sp	! it is OK, put it in place
60*54385Storek	b,a	Lbotch
61*54385Storek3:
62*54385Storek	jmp	%o3 + 8		! success, return %g6
63*54385Storek	 mov	%g6, %o0
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