brk.S revision 1.2
11.2Smrg/* $NetBSD: brk.S,v 1.2 2019/02/05 13:02:35 mrg Exp $ */ 21.1Smatt 31.1Smatt/*- 41.1Smatt * Copyright (c) 2014 The NetBSD Foundation, Inc. 51.1Smatt * All rights reserved. 61.1Smatt * 71.1Smatt * This code is derived from software contributed to The NetBSD Foundation 81.1Smatt * by Matt Thomas of 3am Software Foundry. 91.1Smatt * 101.1Smatt * Redistribution and use in source and binary forms, with or without 111.1Smatt * modification, are permitted provided that the following conditions 121.1Smatt * are met: 131.1Smatt * 1. Redistributions of source code must retain the above copyright 141.1Smatt * notice, this list of conditions and the following disclaimer. 151.1Smatt * 2. Redistributions in binary form must reproduce the above copyright 161.1Smatt * notice, this list of conditions and the following disclaimer in the 171.1Smatt * documentation and/or other materials provided with the distribution. 181.1Smatt * 191.1Smatt * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 201.1Smatt * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 211.1Smatt * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 221.1Smatt * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 231.1Smatt * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 241.1Smatt * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 251.1Smatt * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 261.1Smatt * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 271.1Smatt * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 281.1Smatt * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 291.1Smatt * POSSIBILITY OF SUCH DAMAGE. 301.1Smatt */ 311.1Smatt 321.1Smatt#include "SYS.h" 331.1Smatt 341.1Smatt .globl _C_LABEL(_end) 351.1Smatt .globl _C_LABEL(__curbrk) 361.1Smatt 371.1SmattWEAK_ALIAS(brk, _brk) 381.1Smatt 391.1Smatt .data 401.1Smatt .globl _C_LABEL(__minbrk) 411.1Smatt .hidden _C_LABEL(__minbrk) 421.1Smatt .type _C_LABEL(__minbrk),#object 431.1Smatt .align 3 441.1Smatt_C_LABEL(__minbrk): 451.1Smatt .xword _C_LABEL(_end) 461.1Smatt .size _C_LABEL(__minbrk), 8 471.1Smatt 481.1Smatt/* 491.1Smatt * Change the data segment size 501.1Smatt */ 511.1SmattENTRY(_brk) 521.2Smrg adrp x9, _C_LABEL(__minbrk) 531.1Smatt ldr x10, [x9, #:lo12:_C_LABEL(__minbrk)] 541.1Smatt 551.1Smatt /* 561.1Smatt * Valid the address specified and set to the minimum 571.1Smatt * if the address is below minbrk. 581.1Smatt */ 591.1Smatt cmp x0, x10 601.1Smatt csel x0, x10, x0, lt 611.1Smatt mov x11, x0 621.1Smatt SYSTRAP(break) 631.1Smatt _INVOKE_CERROR() 641.1Smatt 651.1Smatt /* Store the new address in curbrk */ 661.2Smrg adrp x9, _C_LABEL(__curbrk) 671.1Smatt str x11, [x9, #:lo12:_C_LABEL(__curbrk)] 681.1Smatt 691.1Smatt /* Return 0 for success */ 701.1Smatt mov x0, xzr 711.1Smatt ret 721.1SmattEND(_brk) 73