1/*	$NetBSD: setjmp.S,v 1.18 2024/04/04 00:46:41 riastradh Exp $	*/
2
3/*-
4 * Copyright (c) 1990 The Regents of the University of California.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * William Jolitz.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 *	from: @(#)setjmp.s	5.1 (Berkeley) 4/23/90
35 */
36
37#include <machine/asm.h>
38#if defined(LIBC_SCCS)
39	RCSID("$NetBSD: setjmp.S,v 1.18 2024/04/04 00:46:41 riastradh Exp $")
40#endif
41
42/*
43 * C library -- _setjmp, _longjmp
44 *
45 *	longjmp(a,v)
46 * will generate a "return(v)" from the last call to
47 *	setjmp(a)
48 * by restoring registers from the stack.
49 * The previous signal state is restored.
50 */
51
52/*
53 * setjmp(jmp_buf env@esp[4,8))
54 *
55 * ELF symbol: __setjmp14, because the size of jmp_buf changed on some
56 * platforms in 1.4.
57 */
58ENTRY(__setjmp14)
59	/*
60	 * Save the callee-saves registers: %ebp, %ebx, %edi, %esi,
61	 * plus %esp and the return address on the stack since it
62	 * will be overwritten if the caller makes any subroutine
63	 * calls before longjmp.
64	 */
65	movl	4(%esp),%ecx		/* ecx := env */
66	movl	0(%esp),%edx		/* edx := return address */
67	movl	%edx,0(%ecx)
68	movl	%ebx,4(%ecx)
69	movl	%esp,8(%ecx)
70	movl	%ebp,12(%ecx)
71	movl	%esi,16(%ecx)
72	movl	%edi,20(%ecx)
73
74	/* Get the signal mask. */
75	leal	24(%ecx),%edx
76
77	PIC_PROLOGUE
78	pushl	%edx			/* oset (signal mask saved to) */
79	pushl	$0			/* set := NULL */
80	pushl	$0			/* how := 0 (ignored) */
81#ifdef __PIC__
82	call	PIC_PLT(_C_LABEL(__sigprocmask14))
83#else
84	call	_C_LABEL(__sigprocmask14)
85#endif
86	addl	$12,%esp		/* pop sigprocmask args */
87	PIC_EPILOGUE
88
89	xorl	%eax,%eax		/* return 0 first time around */
90	ret
91END(__setjmp14)
92
93/*
94 * longjmp(jmp_buf env@esp[4,8), int val@[8,12))
95 *
96 * ELF symbol: __longjmp14, because the size of jmp_buf changed on some
97 * platforms in 1.4.
98 */
99ENTRY(__longjmp14)
100	/*
101	 * Restore the callee-saves registers: %ebp, %ebx, %edi, %esi,
102	 * plus %esp and the return address on the stack.
103	 */
104	movl	4(%esp),%edx		/* edx := env */
105	movl	8(%esp),%eax		/* eax := val */
106	movl	0(%edx),%ecx		/* ecx := return address */
107	movl	4(%edx),%ebx
108	movl	8(%edx),%esp
109	movl	12(%edx),%ebp
110	movl	16(%edx),%esi
111	movl	20(%edx),%edi
112	movl	%ecx,0(%esp)		/* restore return address */
113
114	/* Restore the signal mask. */
115	leal	24(%edx),%edx
116
117	pushl	%eax			/* save val@eax */
118
119	PIC_PROLOGUE
120	pushl	$0			/* oset := NULL */
121	pushl	%edx			/* set (signal mask restored from) */
122	pushl	$3			/* how := SIG_SETMASK */
123#ifdef __PIC__
124	call	PIC_PLT(_C_LABEL(__sigprocmask14))
125#else
126	call	_C_LABEL(__sigprocmask14)
127#endif
128	addl	$12,%esp		/* pop sigprocmask args */
129	PIC_EPILOGUE
130
131	popl	%eax			/* restore val@eax */
132
133	testl	%eax,%eax		/* val == 0? */
134	jz	3f			/* jump if val == 0 */
135	ret				/* return val@eax */
136
1373:	incl	%eax			/* val@eax := 1 */
138	ret				/* return val@eax */
139END(__longjmp14)
140