1/* 2 * Copyright (c) 1992, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This software was developed by the Computer Systems Engineering group 6 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 7 * contributed to Berkeley. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed by the University of 20 * California, Berkeley and its contributors. 21 * 4. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * from: Header: brk.s,v 1.3 92/06/25 12:56:05 mccanne Exp 38 * $Id: brk.S,v 1.2 1994/02/10 20:15:56 pk Exp $ 39 */ 40 41#if defined(LIBC_SCCS) && !defined(lint) 42 .asciz "@(#)brk.s 8.1 (Berkeley) 6/4/93" 43#endif /* LIBC_SCCS and not lint */ 44 45#include "SYS.h" 46 47 .globl curbrk 48 .globl minbrk 49 50 .data 51minbrk: .long _end ! lower brk limit; also for gmon code 52 .text 53 54#ifdef PIC 55ENTRY(brk) 56 PIC_PROLOGUE(%o5,%o4) 57 ld [%o5 + minbrk], %o4 58 ld [%o4], %o1 ! %o1 = minbrk 59 cmp %o1, %o0 ! if (minbrk > %o0) 60 bg,a 0f 61 mov %o1, %o0 ! %o0 = minbrk 620: 63 mov %o0, %o2 ! save argument to syscall 64 mov SYS_break, %g1 65 t ST_SYSCALL 66 bcc,a 1f 67 ld [%o5 + curbrk], %o4 68 ERROR() 691: 70 retl ! success, return 0 & record new break 71 st %o2, [%o4] 72#else 73ENTRY(brk) 74 sethi %hi(minbrk), %o1 ! %o1 = minbrk 75 ld [%o1 + %lo(minbrk)], %o1 76 cmp %o1, %o0 ! if (minbrk > %o0) 77 bg,a 0f 78 mov %o1, %o0 ! %o0 = minbrk 790: 80 mov %o0, %o2 ! save argument to syscall 81 mov SYS_break, %g1 82 t ST_SYSCALL 83 bcc,a 1f 84 sethi %hi(curbrk), %g1 85 ERROR() 861: 87 retl ! success, return 0 & record new break 88 st %o2, [%g1 + %lo(curbrk)] 89#endif 90