1/* $NetBSD: brk.S,v 1.6 2003/08/07 16:42:04 agc 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 <machine/asm.h> 35__FBSDID("$FreeBSD: releng/10.2/lib/libc/arm/sys/brk.S 271337 2014-09-09 22:24:01Z ian $"); 36#include "SYS.h" 37 38 .globl _C_LABEL(_end) 39 .globl CURBRK 40 41#ifdef WEAK_ALIAS 42WEAK_ALIAS(brk, _brk) 43#endif 44 45 .data 46 .align 0 47 .globl _C_LABEL(minbrk) 48 .type _C_LABEL(minbrk),#object 49_C_LABEL(minbrk): 50 .word _C_LABEL(_end) 51 52/* 53 * Change the data segment size 54 */ 55ENTRY(_brk) 56#ifdef PIC 57 /* Setup the GOT */ 58 ldr r3, .Lgot 59 add r3, pc, r3 60.L1: 61 ldr r1, .Lminbrk 62 ldr r1, [r3, r1] 63#else 64 ldr r1, .Lminbrk 65#endif 66 /* Get the minimum allowable brk address */ 67 ldr r1, [r1] 68 69 /* 70 * Valid the address specified and set to the minimum 71 * if the address is below minbrk. 72 */ 73 cmp r0, r1 74 movlt r0, r1 75 mov r2, r0 76 SYSTRAP(break) 77 bcs PIC_SYM(CERROR, PLT) 78 79#ifdef PIC 80 ldr r1, .Lcurbrk 81 ldr r1, [r3, r1] 82#else 83 ldr r1, .Lcurbrk 84#endif 85 /* Store the new address in curbrk */ 86 str r2, [r1] 87 88 /* Return 0 for success */ 89 mov r0, #0x00000000 90 RET 91 92 .align 2 93#ifdef PIC 94.Lgot: 95 .word _GLOBAL_OFFSET_TABLE_ - (.L1+4) 96#endif 97.Lminbrk: 98 .word PIC_SYM(_C_LABEL(minbrk), GOT) 99.Lcurbrk: 100 .word PIC_SYM(CURBRK, GOT) 101END(_brk) 102