sbrk.S revision 1.4 
1/*
2 * Copyright (c) 1983, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#if defined(SYSLIBC_SCCS) && !defined(lint)
35	/* .asciz "@(#)sbrk.s	8.1 (Berkeley) 6/4/93" */
36	.asciz "$NetBSD: sbrk.S,v 1.4 2000/06/23 15:40:39 kleink Exp $"
37#endif /* SYSLIBC_SCCS and not lint */
38
39#include "SYS.h"
40
41
42	.globl	_end
43	.globl	___minbrk
44	.globl	curbrk
45
46#ifdef WEAK_ALIAS
47WEAK_ALIAS(sbrk, _sbrk)
48#endif
49
50	.data
51___minbrk:
52	.long	_end
53curbrk:	.long	_end
54	.text
55
56#ifdef WEAK_ALIAS
57ENTRY(_sbrk, 0)
58#else
59ENTRY(sbrk, 0)
60#endif
61	addl3	curbrk,4(ap),-(sp)
62	pushl	$1
63	movl	ap,r3
64	movl	sp,ap
65	chmk	$ SYS_break
66	jcs 	err
67	movl	curbrk,r0
68	addl2	4(r3),curbrk
69	ret
70err:
71	jmp	cerror
72