1/* $NetBSD: sbrk.S,v 1.4 2001/07/16 05:50:07 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * from: @(#)sbrk.s 5.1 (Berkeley) 4/23/90 36 */ 37 38#include "SYS.h" 39 40 .globl _C_LABEL(end) 41 42#ifdef WEAK_ALIAS 43WEAK_ALIAS(sbrk, _sbrk) 44#endif 45 46 .data 47 .align 0 48 .globl CURBRK 49 .type CURBRK,#object 50CURBRK: 51 .word _C_LABEL(end) 52 53/* 54 * Change the data segment size 55 */ 56ENTRY(_sbrk) 57#ifdef PIC 58 /* Setup the GOT */ 59 ldr r3, Lgot 60 add r3, pc, r3 61.L1: 62 ldr r2, Lcurbrk 63 ldr r2, [r3, r2] 64#else 65 ldr r2, Lcurbrk 66#endif 67 /* Get the current brk address */ 68 ldr r1, [r2] 69 70 /* Calculate new value */ 71 mov r3, r0 72 add r0, r0, r1 73 SYSTRAP(break) 74 bcs PIC_SYM(CERROR, PLT) 75 76 /* Store new curbrk value */ 77 ldr r0, [r2] 78 add r1, r0, r3 79 str r1, [r2] 80 81 /* Return old curbrk value */ 82#ifdef __APCS_26__ 83 movs r15, r14 84#else 85 mov r15, r14 86#endif 87 88 .align 0 89#ifdef PIC 90Lgot: 91 .word _C_LABEL(_GLOBAL_OFFSET_TABLE_) + (. - (.L1+4)) 92#endif 93Lcurbrk: 94 .word PIC_SYM(CURBRK, GOT) 95