sbrk.S revision 267654 
1/*	$NetBSD: sbrk.S,v 1.16 2005/04/22 06:58:01 simonb Exp $	*/
2
3/*-
4 * Copyright (c) 1991, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Ralph Campbell.
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
35#include <machine/asm.h>
36__FBSDID("$FreeBSD: releng/9.3/lib/libc/mips/sys/sbrk.S 209521 2010-06-25 05:36:36Z jchandra $");
37#include "SYS.h"
38
39#if defined(LIBC_SCCS) && !defined(lint)
40	ASMSTR("from: @(#)sbrk.s	8.1 (Berkeley) 6/4/93")
41	ASMSTR("$NetBSD: sbrk.S,v 1.16 2005/04/22 06:58:01 simonb Exp $")
42#endif /* LIBC_SCCS and not lint */
43
44	.globl	_C_LABEL(__curbrk)
45	.globl	_C_LABEL(_end)
46
47	.data
48_C_LABEL(__curbrk):
49	PTR_WORD	_C_LABEL(_end)
50	.text
51
52LEAF(__sys_sbrk)
53	WEAK_ALIAS(sbrk, __sys_sbrk)
54	WEAK_ALIAS(_sbrk, __sys_sbrk)
55	PIC_PROLOGUE(__sys_sbrk)
56	PTR_LA	t0, _C_LABEL(__curbrk)
57	PTR_L	t0, 0(t0)
58	PTR_ADDU a0, a0, t0
59
60	li	v0, SYS_break
61	syscall
62
63	bne	a3, zero, 1f
64	nop
65	move	v0, t0			# return old val of curbrk from above
66	PTR_LA	t0, _C_LABEL(__curbrk)
67	PTR_S	a0, 0(t0)		# save current val of curbrk from above
68	PIC_RETURN()
69	j	ra
70
711:
72	PIC_TAILCALL(__cerror)
73END(__sys_sbrk)
74