brk.S revision 1.8 1 /* $NetBSD: brk.S,v 1.8 2000/06/23 15:40:39 kleink 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 1.8 2000/06/23 15:40:39 kleink Exp $")
48 #endif
49 #endif /* SYSLIBC_SCCS and not lint */
50
51 #include "SYS.h"
52
53 .globl CURBRK
54 .globl _C_LABEL(__minbrk)
55 .globl _end
56
57 #ifdef WEAK_ALIAS
58 WEAK_ALIAS(brk, _brk)
59 #endif
60
61 .data
62 _C_LABEL(__minbrk):
63 .long _end ! lower brk limit; also for gmon code
64 .text
65
66 #ifdef WEAK_ALIAS
67 ENTRY(_brk)
68 #else
69 ENTRY(brk)
70 #endif
71 #ifdef PIC
72 PIC_PROLOGUE(%o5,%o4)
73 ld [%o5 + _C_LABEL(__minbrk)], %o4
74 ld [%o4], %o1 ! %o1 = minbrk
75 cmp %o1, %o0 ! if (minbrk > %o0)
76 bg,a 0f
77 mov %o1, %o0 ! %o0 = minbrk
78 0:
79 mov %o0, %o2 ! save argument to syscall
80 mov SYS_break, %g1
81 t ST_SYSCALL
82 bcc,a 1f
83 ld [%o5 + CURBRK], %o4
84 ERROR()
85 1:
86 retl ! success, return 0 & record new break
87 st %o2, [%o4]
88 #else
89 sethi %hi(_C_LABEL(__minbrk)), %o1 ! %o1 = minbrk
90 ld [%o1 + %lo(_C_LABEL(__minbrk))], %o1
91 cmp %o1, %o0 ! if (minbrk > %o0)
92 bg,a 0f
93 mov %o1, %o0 ! %o0 = minbrk
94 0:
95 mov %o0, %o2 ! save argument to syscall
96 mov SYS_break, %g1
97 t ST_SYSCALL
98 bcc,a 1f
99 sethi %hi(CURBRK), %g1
100 ERROR()
101 1:
102 retl ! success, return 0 & record new break
103 st %o2, [%g1 + %lo(CURBRK)]
104 #endif
105