1/* $NetBSD: sbrk.S,v 1.22 2014/05/23 02:34:19 uebayasi Exp $ */ 2 3/*- 4 * Copyright (c) 1990 The Regents of the University of California. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * William Jolitz. 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 * from: @(#)sbrk.s 5.1 (Berkeley) 4/23/90 35 */ 36 37#include <machine/asm.h> 38#if defined(SYSLIBC_SCCS) && !defined(lint) 39 RCSID("$NetBSD: sbrk.S,v 1.22 2014/05/23 02:34:19 uebayasi Exp $") 40#endif /* SYSLIBC_SCCS and not lint */ 41 42#include "SYS.h" 43 44 .globl _end 45 .globl CURBRK 46 47#ifdef WEAK_ALIAS 48WEAK_ALIAS(sbrk, _sbrk) 49#endif 50 51 .data 52CURBRK: .long _end 53 .text 54 55ENTRY(_sbrk) 56#ifdef __PIC__ 57 movl 4(%esp),%ecx 58 PIC_PROLOGUE 59 movl PIC_GOT(CURBRK),%edx 60 PIC_EPILOGUE 61 movl (%edx),%eax 62 test %ecx,%ecx 63 jz out 64 addl %eax,%ecx 65 movl %ecx,4(%esp) 66 OSYSTRAP(break) /* don't clobber %ecx */ 67 jc err 68 PIC_PROLOGUE 69 movl PIC_GOT(CURBRK),%edx 70 PIC_EPILOGUE 71 movl (%edx),%eax 72 movl %ecx,(%edx) 73out: 74 ret 75err: 76 jmp CERROR 77#else 78 movl 4(%esp),%ecx 79 movl CURBRK,%eax 80 test %ecx,%ecx 81 jz out 82 addl %eax,4(%esp) 83 OSYSTRAP(break) /* don't clobber %ecx */ 84 jc err 85 movl CURBRK,%eax 86 addl %ecx,CURBRK 87out: 88 ret 89err: 90 jmp CERROR 91#endif 92END(_sbrk) 93