brk.S revision 92999
1/*- 2 * Copyright (c) 1990 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * William Jolitz. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37#if defined(SYSLIBC_SCCS) && !defined(lint) 38 .asciz "@(#)brk.s 5.2 (Berkeley) 12/17/90" 39#endif /* SYSLIBC_SCCS and not lint */ 40#include <machine/asm.h> 41__FBSDID("$FreeBSD: head/lib/libc/i386/sys/brk.S 92999 2002-03-23 02:10:28Z obrien $"); 42 43#include "SYS.h" 44 45 .globl HIDENAME(curbrk) 46 .globl HIDENAME(minbrk) 47ENTRY(_brk) 48 jmp ok 49 50ENTRY(brk) 51#ifdef PIC 52 movl 4(%esp),%eax 53 PIC_PROLOGUE 54 movl PIC_GOT(HIDENAME(curbrk)),%edx # set up GOT addressing 55 movl PIC_GOT(HIDENAME(minbrk)),%ecx # 56 PIC_EPILOGUE 57 cmpl %eax,(%ecx) 58 jbe ok 59 movl (%ecx),%eax 60 movl %eax,4(%esp) 61ok: 62 mov $SYS_break,%eax 63 KERNCALL 64 jb err 65 movl 4(%esp),%eax 66 movl %eax,(%edx) 67 movl $0,%eax 68 ret 69err: 70 PIC_PROLOGUE 71 jmp PIC_PLT(HIDENAME(cerror)) 72 73#else 74 75 movl 4(%esp),%eax 76 cmpl %eax,HIDENAME(minbrk) 77 jbe ok 78 movl HIDENAME(minbrk),%eax 79 movl %eax,4(%esp) 80ok: 81 mov $SYS_break,%eax 82 KERNCALL 83 jb err 84 movl 4(%esp),%eax 85 movl %eax,HIDENAME(curbrk) 86 movl $0,%eax 87 ret 88err: 89 jmp HIDENAME(cerror) 90#endif 91