1/* $NetBSD: brk.S,v 1.13 2013/09/12 15:36:15 joerg 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 ldr r1, .Lminbrk 56#ifdef __PIC__ 57 adr r3, .Lminbrk 58 adds r1, r1, r3 59#endif 60 /* Get the minimum allowable brk address */ 61 ldr r1, [r1] 62 63 /* 64 * Valid the address specified and set to the minimum 65 * if the address is below minbrk. 66 */ 67 cmp r0, r1 68#ifdef __thumb__ 69 bcs 1f 70 mov r0, r1 711: 72#else 73 movcc r0, r1 74#endif 75 mov r2, r0 76 SYSTRAP(break) 77 _INVOKE_CERROR() 78 79 ldr r1, .Lcurbrk 80#ifdef __PIC__ 81 adds r1, r1, r3 82#endif 83 /* Store the new address in curbrk */ 84 str r2, [r1] 85 86 /* Return 0 for success */ 87 movs r0, #0 88 RET 89 90 .align 0 91.Lminbrk: 92 .word REL_SYM(_C_LABEL(__minbrk), .Lminbrk) 93.Lcurbrk: 94 .word REL_SYM(_C_LABEL(__curbrk), .Lminbrk) 95END(_brk) 96