1/* $NetBSD: brk.S,v 1.1 2014/08/10 05:47:37 matt Exp $ */ 2 3/*- 4 * Copyright (c) 2014 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Matt Thomas of 3am Software Foundry. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32#include "SYS.h" 33 34 .globl _C_LABEL(_end) 35 .globl _C_LABEL(__curbrk) 36 37WEAK_ALIAS(brk, _brk) 38 39 .data 40 .globl _C_LABEL(__minbrk) 41 .hidden _C_LABEL(__minbrk) 42 .type _C_LABEL(__minbrk),#object 43 .align 3 44_C_LABEL(__minbrk): 45 .xword _C_LABEL(_end) 46 .size _C_LABEL(__minbrk), 8 47 48/* 49 * Change the data segment size 50 */ 51ENTRY(_brk) 52 adr x9, _C_LABEL(__minbrk) 53 ldr x10, [x9, #:lo12:_C_LABEL(__minbrk)] 54 55 /* 56 * Valid the address specified and set to the minimum 57 * if the address is below minbrk. 58 */ 59 cmp x0, x10 60 csel x0, x10, x0, lt 61 mov x11, x0 62 SYSTRAP(break) 63 _INVOKE_CERROR() 64 65 /* Store the new address in curbrk */ 66 adr x9, _C_LABEL(__curbrk) 67 str x11, [x9, #:lo12:_C_LABEL(__curbrk)] 68 69 /* Return 0 for success */ 70 mov x0, xzr 71 ret 72END(_brk) 73