brk.S revision 1.1 
1/*	$NetBSD: brk.S,v 1.1 1997/03/29 20:56:02 thorpej 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: brk.s,v 1.3 92/06/25 12:56:05 mccanne Exp
40 */
41
42#if defined(LIBC_SCCS) && !defined(lint)
43	.asciz "@(#)brk.s	8.1 (Berkeley) 6/4/93"
44#endif /* LIBC_SCCS and not lint */
45
46#include "SYS.h"
47
48	.globl	curbrk
49
50	.text
51
52#ifdef PIC
53	XXX
54#else
55ENTRY(brk)
56	lis	5,_end@ha		# r5 = &_end
57	addi	5,5,_end@l
58	cmplw	5,3			# if (&_end <= r3)
59	bgt	0f
60	mr	5,3			# r5 = r3
610:
62	mr	3,5			# new break value
63	li	0,SYS_break
64	sc				# assume, that r5 is kept
65	bso	1f
66	lis	6,curbrk@ha
67	stw	5,curbrk@l(6)		# record new break
68	blr				# return 0
69
701:
71	b	cerror
72#endif
73