1/*	$NetBSD: brk.S,v 1.6 2003/08/07 16:42:04 agc Exp $	*/
2
3/*-
4 * Copyright (c) 1990 The Regents of the University of California.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 *	from: @(#)brk.s	5.2 (Berkeley) 12/17/90
32 */
33
34#include <machine/asm.h>
35__FBSDID("$FreeBSD: releng/10.3/lib/libc/arm/sys/brk.S 271337 2014-09-09 22:24:01Z ian $");
36#include "SYS.h"
37
38	.globl	_C_LABEL(_end)
39	.globl	CURBRK
40
41#ifdef WEAK_ALIAS
42WEAK_ALIAS(brk, _brk)
43#endif
44
45	.data
46	.align	0
47	.globl	_C_LABEL(minbrk)
48	.type	_C_LABEL(minbrk),#object
49_C_LABEL(minbrk):
50	.word	_C_LABEL(_end)
51
52/*
53 * Change the data segment size
54 */
55ENTRY(_brk)
56#ifdef PIC
57	/* Setup the GOT */
58	ldr	r3, .Lgot
59	add	r3, pc, r3
60.L1:
61	ldr	r1, .Lminbrk
62	ldr	r1, [r3, r1]
63#else
64	ldr	r1, .Lminbrk
65#endif
66	/* Get the minimum allowable brk address */
67	ldr	r1, [r1]
68
69	/*
70	 * Valid the address specified and set to the minimum
71	 * if the address is below minbrk.
72	 */
73	cmp	r0, r1
74	movlt	r0, r1
75	mov	r2, r0
76	SYSTRAP(break)
77	bcs	PIC_SYM(CERROR, PLT)
78
79#ifdef PIC
80	ldr	r1, .Lcurbrk
81	ldr	r1, [r3, r1]
82#else
83	ldr	r1, .Lcurbrk
84#endif
85	/* Store the new address in curbrk */
86	str	r2, [r1]
87
88	/* Return 0 for success */
89	mov	r0, #0x00000000
90	RET
91
92	.align	2
93#ifdef PIC
94.Lgot:
95	.word	_GLOBAL_OFFSET_TABLE_ - (.L1+4)
96#endif
97.Lminbrk:
98	.word	PIC_SYM(_C_LABEL(minbrk), GOT)
99.Lcurbrk:
100	.word	PIC_SYM(CURBRK, GOT)
101END(_brk)
102