brk.S revision 1.9
1 /* $NetBSD: brk.S,v 1.9 2000/07/25 20:15:40 mycroft Exp $ */ 2 3 /* 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This software was developed by the Computer Systems Engineering group 8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 9 * contributed to Berkeley. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * from: Header: brk.s,v 1.3 92/06/25 12:56:05 mccanne Exp 40 */ 41 42 #include <machine/asm.h> 43 #if defined(SYSLIBC_SCCS) && !defined(lint) 44 #if 0 45 .asciz "@(#)brk.s 8.1 (Berkeley) 6/4/93" 46 #else 47 RCSID("$NetBSD: brk.S,v 1.9 2000/07/25 20:15:40 mycroft Exp $") 48 #endif 49 #endif /* SYSLIBC_SCCS and not lint */ 50 51 #include "SYS.h" 52 53 .globl _C_LABEL(__curbrk) 54 .globl _C_LABEL(__minbrk) 55 .globl _C_LABEL(_end) 56 57 #ifdef WEAK_ALIAS 58 WEAK_ALIAS(brk, _brk) 59 #endif 60 61 .data 62 .align 8 63 _C_LABEL(__minbrk): 64 .xword _C_LABEL(_end) /* lower brk limit; also for gmon code */ 65 .text 66 67 ENTRY(_brk) 68 #ifdef PIC 69 PIC_PROLOGUE(%o5,%o4) 70 set _C_LABEL(__minbrk), %o4 71 ldx [%o5 + %o4], %o4 72 ldx [%o4], %o1 /* %o1 = minbrk */ 73 cmp %o1, %o0 /* if (minbrk > %o0) */ 74 movg %xcc, %o1, %o0 /* %o0 = minbrk */ 75 mov %o0, %o2 /* save argument to syscall */ 76 mov SYS_break, %g1 77 t ST_SYSCALL 78 set _C_LABEL(__curbrk), %o3 79 bcc,a,pt %icc, 1f 80 ldx [%o5 + %o3], %o4 81 ERROR() 82 1: 83 retl /* success, return 0 & record new break */ 84 stx %o2, [%o4] 85 #else 86 sethi %hi(_C_LABEL(__minbrk)), %o1 /* %o1 = minbrk */ 87 ldx [%o1 + %lo(_C_LABEL(__minbrk))], %o1 88 cmp %o1, %o0 /* if (minbrk > %o0) */ 89 movg %xcc, %o1, %o0 /* %o0 = minbrk */ 90 mov %o0, %o2 /* save argument to syscall */ 91 mov SYS_break, %g1 92 t ST_SYSCALL 93 bcc,a,pt %icc,1f 94 sethi %hi(_C_LABEL(__curbrk)), %g1 95 ERROR() 96 1: 97 retl /* success, return 0 & record new break */ 98 stx %o2, [%g1 + %lo(_C_LABEL(__curbrk))] 99 #endif 100
Indexes created Tue Oct 28 12:10:06 GMT 2025