xref: /netbsd/lib/libc/arch/sparc64/sys/brk.S (revision bf9ec67e)
1/*	$NetBSD: brk.S,v 1.10 2002/05/07 01:34:22 eeh 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#include <machine/asm.h>
43#if defined(SYSLIBC_SCCS) && !defined(lint)
44#if 0
45	.asciz "@(#)brk.s	8.1 (Berkeley) 6/4/93"
46#else
47	RCSID("$NetBSD: brk.S,v 1.10 2002/05/07 01:34:22 eeh Exp $")
48#endif
49#endif /* SYSLIBC_SCCS and not lint */
50
51#include "SYS.h"
52
53	.globl	_C_LABEL(__curbrk)
54	.globl	_C_LABEL(__minbrk)
55	.globl	_C_LABEL(_end)
56
57#ifdef WEAK_ALIAS
58WEAK_ALIAS(brk, _brk)
59#endif
60
61	.data
62	.align	8
63_C_LABEL(__minbrk):
64	.xword	_C_LABEL(_end)		/* lower brk limit; also for gmon code */
65	.text
66
67ENTRY(_brk)
68#ifdef PIC
69#ifdef BIGPIC
70	PIC_PROLOGUE(%o5,%o4)
71	set	_C_LABEL(__minbrk), %o4
72	ldx	[%o5 + %o4], %o4
73	ldx	[%o4], %o1		/* %o1 = minbrk */
74	cmp	%o1, %o0		/* if (minbrk > %o0) */
75	movg	%xcc, %o1, %o0		/*	%o0 = minbrk */
76	mov	%o0, %o2		/* save argument to syscall */
77	mov	SYS_break, %g1
78	t	ST_SYSCALL
79	set	_C_LABEL(__curbrk), %o3
80	bcc,a,pt	%icc, 1f
81	 ldx	[%o5 + %o3], %o4
82	ERROR()
831:
84	retl				/* success, return 0 & record new break */
85	 stx	%o2, [%o4]
86#else
87	PIC_PROLOGUE(%o5,%o4)
88	ldx	[%o5 + _C_LABEL(__minbrk)], %o4
89	ldx	[%o4], %o1		/* %o1 = minbrk */
90	cmp	%o1, %o0		/* if (minbrk > %o0) */
91	movg	%xcc, %o1, %o0		/*	%o0 = minbrk */
92	mov	%o0, %o2		/* save argument to syscall */
93	mov	SYS_break, %g1
94	t	ST_SYSCALL
95	bcc,a,pt	%icc, 1f
96	 ldx	[%o5 + _C_LABEL(__curbrk)], %o4
97	ERROR()
981:
99	retl				/* success, return 0 & record new break */
100	 stx	%o2, [%o4]
101#endif
102#else
103	sethi	%hi(_C_LABEL(__minbrk)), %o1	/* %o1 = minbrk */
104	ldx	[%o1 + %lo(_C_LABEL(__minbrk))], %o1
105	cmp	%o1, %o0		/* if (minbrk > %o0) */
106	movg	%xcc, %o1, %o0		/*	%o0 = minbrk */
107	mov	%o0, %o2		/* save argument to syscall */
108	mov	SYS_break, %g1
109	t	ST_SYSCALL
110	bcc,a,pt	%icc,1f
111	 sethi	%hi(_C_LABEL(__curbrk)), %g1
112	ERROR()
1131:
114	retl				/* success, return 0 & record new break */
115	 stx	%o2, [%g1 + %lo(_C_LABEL(__curbrk))]
116#endif
117