1/* $NetBSD: sbrk.S,v 1.10 2013/08/01 05:32:33 matt 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: @(#)sbrk.s 5.1 (Berkeley) 4/23/90 32 */ 33 34#include "SYS.h" 35 36 .globl _C_LABEL(_end) 37 38#ifdef WEAK_ALIAS 39WEAK_ALIAS(sbrk, _sbrk) 40#endif 41 42 .data 43 .align 0 44 .globl _C_LABEL(__curbrk) 45 .hidden _C_LABEL(__curbrk) 46 .type _C_LABEL(__curbrk),#object 47_C_LABEL(__curbrk): 48 .word _C_LABEL(_end) 49 50/* 51 * Change the data segment size 52 */ 53ENTRY(_sbrk) 54 /* get address or PC offset to __curbrk */ 55 ldr r2, .Lcurbrk 56#ifdef PIC 57 add r2, pc, r2 58.L1: 59#endif 60 61 /* Get the current brk address */ 62 ldr r1, [r2] 63 64 /* Calculate new value */ 65 mov r3, r0 66 add r0, r0, r1 67 SYSTRAP(break) 68 bcs CERROR 69 70 /* Store new curbrk value */ 71 ldr r0, [r2] 72 add r1, r0, r3 73 str r1, [r2] 74 75 /* Return old curbrk value */ 76 RET 77 78 .align 0 79.Lcurbrk: 80#ifdef PIC 81 .word _C_LABEL(__curbrk) - (.L1+4) 82#else 83 .word _C_LABEL(__curbrk) 84#endif 85