1/* $OpenBSD: brk.S,v 1.4 2004/10/01 04:08:45 jsg Exp $ */ 2/* $NetBSD: brk.S,v 1.7 2003/12/26 11:23:44 martin 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: @(#)brk.s 5.2 (Berkeley) 12/17/90 33 */ 34 35#include "SYS.h" 36 37 .globl _C_LABEL(end) 38 .globl CURBRK 39 40#ifdef WEAK_ALIAS 41WEAK_ALIAS(brk, _brk) 42#endif 43 44 .data 45 .align 0 46 .globl _C_LABEL(__minbrk) 47 .type _C_LABEL(__minbrk),#object 48_C_LABEL(__minbrk): 49 .word _C_LABEL(end) 50 51/* 52 * Change the data segment size 53 */ 54SYSENTRY(_brk) 55#ifdef PIC 56 /* Setup the GOT */ 57 ldr r3, .Lgot 58 ldr r1, .Lminbrk 59.L1: 60 add r3, pc, r3 61 ldr r1, [r3, r1] 62#else 63 ldr r1, .Lminbrk 64#endif 65 /* Get the minimum allowable brk address */ 66 ldr r1, [r1] 67 68 /* 69 * Valid the address specified and set to the minimum 70 * if the address is below minbrk. 71 */ 72 cmp r0, r1 73 movcc r0, r1 74 mov r2, r0 75 SYSTRAP(break) 76 bcs PIC_SYM(CERROR, PLT) 77 78#ifdef PIC 79 ldr r1, .Lcurbrk 80 ldr r1, [r3, r1] 81#else 82 ldr r1, .Lcurbrk 83#endif 84 /* Store the new address in curbrk */ 85 str r2, [r1] 86 87 /* Return 0 for success */ 88 mov r0, #0x00000000 89 mov r15, r14 90 91 .align 2 92#ifdef PIC 93.Lgot: 94 .word _C_LABEL(_GLOBAL_OFFSET_TABLE_) - (.L1+8) 95#endif 96.Lminbrk: 97 .word PIC_SYM(_C_LABEL(__minbrk), GOT) 98.Lcurbrk: 99 .word PIC_SYM(CURBRK, GOT) 100