sbrk.S revision 1.8 
1/*	$NetBSD: sbrk.S,v 1.8 1997/07/16 14:37:32 christos 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. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *	This product includes software developed by the University of
21 *	California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 *    may be used to endorse or promote products derived from this software
24 *    without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 *
38 *	from: @(#)sbrk.s	5.1 (Berkeley) 4/23/90
39 */
40
41#include <machine/asm.h>
42#if defined(SYSLIBC_SCCS) && !defined(lint)
43	RCSID("$NetBSD: sbrk.S,v 1.8 1997/07/16 14:37:32 christos Exp $")
44#endif /* SYSLIBC_SCCS and not lint */
45
46#include "SYS.h"
47
48	.globl	_end
49	.globl	curbrk
50
51	.data
52curbrk:	.long	_end
53	.text
54
55ENTRY(sbrk)
56#ifdef PIC
57	movl	4(%esp),%ecx
58	PIC_PROLOGUE
59	movl	PIC_GOT(curbrk),%edx
60	PIC_EPILOGUE
61	movl	(%edx),%eax
62	addl	%eax,4(%esp)
63	movl	$(SYS_break),%eax
64	int	$0x80
65	jc	err
66	PIC_PROLOGUE
67	movl	PIC_GOT(curbrk),%edx
68	PIC_EPILOGUE
69	movl	(%edx),%eax
70	addl	%ecx,(%edx)
71	ret
72err:
73	jmp	PIC_PLT(cerror)
74
75#else
76
77	movl	4(%esp),%ecx
78	movl	curbrk,%eax
79	addl	%eax,4(%esp)
80	movl	$(SYS_break),%eax
81	int	$0x80
82	jc	err
83	movl	curbrk,%eax
84	addl	%ecx,curbrk
85	ret
86err:
87	jmp	cerror
88#endif
89