1/* $NetBSD: sbrk.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 36WEAK_ALIAS(sbrk, _sbrk) 37 38 .data 39 .align 3 40 .globl _C_LABEL(__curbrk) 41 .hidden _C_LABEL(__curbrk) 42 .type _C_LABEL(__curbrk),#object 43_C_LABEL(__curbrk): 44 .xword _C_LABEL(_end) 45 .size _C_LABEL(_end), 8 46 47/* 48 * Change the data segment size 49 */ 50ENTRY(_sbrk) 51 /* get address or offset to __curbrk */ 52 adrp x9, _C_LABEL(__curbrk) 53 54 /* Get the current brk address */ 55 ldr x1, [x9, #:lo12:_C_LABEL(__curbrk)] 56 57 /* Calculate new value */ 58 mov x10, x0 59 add x0, x0, x1 60 SYSTRAP(break) 61 _INVOKE_CERROR() 62 63 /* Store new curbrk value */ 64 ldr x0, [x9, #:lo12:_C_LABEL(__curbrk)] 65 add x1, x0, x10 66 str x1, [x9, #:lo12:_C_LABEL(__curbrk)] 67 68 /* Return old curbrk value */ 69 ret 70END(_sbrk) 71