1/* $OpenBSD: sbrk.S,v 1.9 2016/08/06 19:16:09 guenther Exp $ */ 2/* $NetBSD: sbrk.S,v 1.7 2003/08/07 16:42:05 agc Exp $ */ 3 4/*- 5 * Copyright (c) 1990 The Regents of the University of California. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * from: @(#)sbrk.s 5.1 (Berkeley) 4/23/90 33 */ 34 35#include "SYS.h" 36 37 .globl _C_LABEL(_end) 38 39 .data 40 .align 0 41 .globl __curbrk 42 .type __curbrk,#object 43 .hidden __curbrk 44__curbrk: 45 .word _C_LABEL(_end) 46 END(__curbrk) 47 48 .weak sbrk 49/* 50 * Change the data segment size 51 */ 52ENTRY(sbrk) 53#ifdef __PIC__ 54 /* Setup the GOT */ 55 ldr r3, .Lgot 56 ldr r2, .Lcurbrk 57.L1: 58 add r3, pc, r3 59 ldr r2, [r3, r2] 60#else 61 ldr r2, .Lcurbrk 62#endif 63 /* Get the current brk address */ 64 ldr r1, [r2] 65 66 /* Calculate new value */ 67 mov r3, r0 68 add r0, r0, r1 69 SYSTRAP(break) 70 bcs CERROR 71 72 /* Store new curbrk value */ 73 ldr r0, [r2] 74 add r1, r0, r3 75 str r1, [r2] 76 77 /* Return old curbrk value */ 78 mov r15, r14 79 80 .align 0 81#ifdef __PIC__ 82.Lgot: 83 .word _C_LABEL(_GLOBAL_OFFSET_TABLE_) - (.L1+8) 84#endif 85.Lcurbrk: 86 .word PIC_SYM(__curbrk, GOT) 87END(sbrk) 88