1/* $NetBSD: sbrk.S,v 1.19 2013/06/26 08:38:34 matt Exp $ */ 2 3/*- 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Ralph Campbell. 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 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35#include "SYS.h" 36 37#if defined(LIBC_SCCS) && !defined(lint) 38#if 0 39 RCSID("from: @(#)sbrk.s 8.1 (Berkeley) 6/4/93") 40#else 41 RCSID("$NetBSD: sbrk.S,v 1.19 2013/06/26 08:38:34 matt Exp $") 42#endif 43#endif /* LIBC_SCCS and not lint */ 44 45 .globl _C_LABEL(__curbrk) 46 .globl _C_LABEL(_end) 47 48#ifdef WEAK_ALIAS 49WEAK_ALIAS(sbrk, _sbrk) 50#endif 51 52 .data 53_C_LABEL(__curbrk): 54 PTR_WORD _C_LABEL(_end) 55 .text 56 57LEAF(_sbrk) 58 PIC_PROLOGUE(_sbrk) 59 PTR_LA t0, _C_LABEL(__curbrk) 60 PTR_L t1, 0(t0) 61 PTR_ADDU a0, a0, t1 # compute current break 62 SYSTRAP(break) 63 bne a3, zero, 1f 64 move v0, t1 # return old val of curbrk from above 65 PTR_LA t0, _C_LABEL(__curbrk) 66 PTR_S a0, 0(t0) # save current val of curbrk from above 67 PIC_RETURN() 681: 69 PIC_TAILCALL(__cerror) 70END(_sbrk) 71