1/* $NetBSD: brk.S,v 1.8 2004/08/21 11:30:17 rearnsha 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: @(#)brk.s 5.2 (Berkeley) 12/17/90 32 */ 33 34#include "SYS.h" 35 36 .globl _C_LABEL(_end) 37 .globl CURBRK 38 39#ifdef WEAK_ALIAS 40WEAK_ALIAS(brk, _brk) 41#endif 42 43 .data 44 .align 0 45 .globl _C_LABEL(__minbrk) 46 .type _C_LABEL(__minbrk),#object 47_C_LABEL(__minbrk): 48 .word _C_LABEL(_end) 49 50/* 51 * Change the data segment size 52 */ 53ENTRY(_brk) 54#ifdef PIC 55 /* Setup the GOT */ 56 ldr r3, .Lgot 57 add r3, pc, r3 58.L1: 59 ldr r1, .Lminbrk 60 ldr r1, [r3, r1] 61#else 62 ldr r1, .Lminbrk 63#endif 64 /* Get the minimum allowable brk address */ 65 ldr r1, [r1] 66 67 /* 68 * Valid the address specified and set to the minimum 69 * if the address is below minbrk. 70 */ 71 cmp r0, r1 72 movcc r0, r1 73 mov r2, r0 74 SYSTRAP(break) 75 bcs PIC_SYM(CERROR, PLT) 76 77#ifdef PIC 78 ldr r1, .Lcurbrk 79 ldr r1, [r3, r1] 80#else 81 ldr r1, .Lcurbrk 82#endif 83 /* Store the new address in curbrk */ 84 str r2, [r1] 85 86 /* Return 0 for success */ 87 mov r0, #0x00000000 88 RET 89 90 .align 2 91#ifdef PIC 92.Lgot: 93 .word _C_LABEL(_GLOBAL_OFFSET_TABLE_) + (. - (.L1+4)) 94#endif 95.Lminbrk: 96 .word PIC_SYM(_C_LABEL(__minbrk), GOT) 97.Lcurbrk: 98 .word PIC_SYM(CURBRK, GOT) 99