minix/lib/libc/arch/arm/sys/sbrk.S

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/* $NetBSD: sbrk.S,v 1.8 2004/08/21 11:30:17 rearnsha Exp $ */
/*-
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: @(#)sbrk.s 5.1 (Berkeley) 4/23/90
*/
#include "SYS.h"
.globl _C_LABEL(end)
#ifdef WEAK_ALIAS
WEAK_ALIAS(sbrk, _sbrk)
#endif
.data
.align 0
.globl CURBRK
.type CURBRK,#object
CURBRK:
.word _C_LABEL(end)
/*
* Change the data segment size
*/
ENTRY(_sbrk)
#ifdef PIC
/* Setup the GOT */
ldr r3, .Lgot
add r3, pc, r3
.L1:
ldr r2, .Lcurbrk
ldr r2, [r3, r2]
#else
ldr r2, .Lcurbrk
#endif
/* Get the current brk address */
ldr r1, [r2]
/* Calculate new value */
mov r3, r0
add r0, r0, r1
SYSTRAP(break)
bcs PIC_SYM(CERROR, PLT)
/* Store new curbrk value */
ldr r0, [r2]
add r1, r0, r3
str r1, [r2]
/* Return old curbrk value */
RET
.align 0
#ifdef PIC
.Lgot:
.word _C_LABEL(_GLOBAL_OFFSET_TABLE_) + (. - (.L1+4))
#endif
.Lcurbrk:
.word PIC_SYM(CURBRK, GOT)