1/* $NetBSD: brk.S,v 1.11 2013/08/01 05:54:24 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: @(#)brk.s 5.2 (Berkeley) 12/17/90 32 */ 33 34#include "SYS.h" 35 36 .globl _C_LABEL(_end) 37 .globl _C_LABEL(__curbrk) 38 39#ifdef WEAK_ALIAS 40WEAK_ALIAS(brk, _brk) 41#endif 42 43 .data 44 .align 0 45 .globl _C_LABEL(__minbrk) 46 .hidden _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 */ 54ENTRY(_brk) 55#ifdef PIC 56 /* Setup the GOT */ 57 ldr r3, .Lgot 58 add r3, pc, r3 59.L1: 60 ldr r1, .Lminbrk 61 add 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 CERROR 77 78#ifdef PIC 79 ldr r1, .Lcurbrk 80 add 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 RET 90 91 .align 2 92#ifdef PIC 93.Lgot: 94 .word _C_LABEL(_GLOBAL_OFFSET_TABLE_) + (. - (.L1+4)) 95#endif 96.Lminbrk: 97 .word PIC_SYM(_C_LABEL(__minbrk), GOTOFF) 98.Lcurbrk: 99 .word PIC_SYM(_C_LABEL(__curbrk), GOTOFF) 100