xref: /netbsd-src/lib/libc/arch/m68k/sys/brk.S (revision ae9172d6cd9432a6a1a56760d86b32c57a66c39c)
1/*-
2 * Copyright (c) 1990 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * the Systems Programming Group of the University of Utah Computer
7 * Science Department.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 *    must display the following acknowledgement:
19 *	This product includes software developed by the University of
20 *	California, Berkeley and its contributors.
21 * 4. Neither the name of the University nor the names of its contributors
22 *    may be used to endorse or promote products derived from this software
23 *    without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 */
37
38#if defined(LIBC_SCCS) && !defined(lint)
39	.text
40	/*.asciz "from: @(#)brk.s	5.1 (Berkeley) 5/12/90"*/
41	.asciz "$Id: brk.S,v 1.4 1994/08/04 05:02:41 chopps Exp $"
42#endif /* LIBC_SCCS and not lint */
43
44#include "SYS.h"
45
46	.globl	_end
47	.globl	minbrk
48	.globl	curbrk
49
50	.data
51minbrk:	.long	_end
52	.text
53
54ENTRY(brk)
55#ifdef	PIC
56	movl	#__GLOBAL_OFFSET_TABLE_,a1
57	lea	pc@(0,a1:l),a1
58	movl	a1@(minbrk:w),a0
59	movl	a0@,d0
60#else
61	movl	minbrk,d0
62#endif
63	cmpl	sp@(4),d0
64	jle	ok
65	movl	d0,sp@(4)
66ok:
67	movl	#SYS_break,d0
68	trap	#0
69	jcs	err
70#ifdef	PIC
71	movl	a1@(curbrk:w),a0
72	movl	sp@(4),a0@
73#else
74	movl	sp@(4),curbrk
75#endif
76	clrl	d0
77	rts
78err:
79	jra	cerror
80