1/* $NetBSD: brk.S,v 1.13 2013/09/12 15:36:16 joerg 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. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * from: Header: brk.s,v 1.3 92/06/25 12:56:05 mccanne Exp 36 */ 37 38#include <machine/asm.h> 39#if defined(SYSLIBC_SCCS) && !defined(lint) 40#if 0 41 .asciz "@(#)brk.s 8.1 (Berkeley) 6/4/93" 42#else 43 RCSID("$NetBSD: brk.S,v 1.13 2013/09/12 15:36:16 joerg Exp $") 44#endif 45#endif /* SYSLIBC_SCCS and not lint */ 46 47#include "SYS.h" 48 49 .globl _C_LABEL(__curbrk) 50 .globl _C_LABEL(__minbrk) 51 .globl _C_LABEL(_end) 52 53#ifdef WEAK_ALIAS 54WEAK_ALIAS(brk, _brk) 55#endif 56 57 .data 58 .align 8 59_C_LABEL(__minbrk): 60 .xword _C_LABEL(_end) /* lower brk limit; also for gmon code */ 61 .text 62 63#if __PIC__ - 0 >= 2 64 65ENTRY(_brk) 66 PIC_PROLOGUE(%o5,%o4) 67 set _C_LABEL(__minbrk), %o4 68 ldx [%o5 + %o4], %o4 69 ldx [%o4], %o1 /* %o1 = minbrk */ 70 cmp %o1, %o0 /* if (minbrk > %o0) */ 71 movgu %xcc, %o1, %o0 /* %o0 = minbrk */ 72 mov %o0, %o2 /* save argument to syscall */ 73 mov SYS_break, %g1 74 t ST_SYSCALL 75 set _C_LABEL(__curbrk), %o3 76 bcc,a,pt %icc, 1f 77 ldx [%o5 + %o3], %o4 78 ERROR() 791: 80 retl /* success, return 0 & record new break */ 81 stx %o2, [%o4] 82 83#elif __PIC__ - 0 >= 1 84 85ENTRY(_brk) 86 PIC_PROLOGUE(%o5,%o4) 87 ldx [%o5 + _C_LABEL(__minbrk)], %o4 88 ldx [%o4], %o1 /* %o1 = minbrk */ 89 cmp %o1, %o0 /* if (minbrk > %o0) */ 90 movgu %xcc, %o1, %o0 /* %o0 = minbrk */ 91 mov %o0, %o2 /* save argument to syscall */ 92 mov SYS_break, %g1 93 t ST_SYSCALL 94 bcc,a,pt %icc, 1f 95 ldx [%o5 + _C_LABEL(__curbrk)], %o4 96 ERROR() 971: 98 retl /* success, return 0 & record new break */ 99 stx %o2, [%o4] 100 101#else 102 103ENTRY(_brk) 104 sethi %hi(_C_LABEL(__minbrk)), %o1 /* %o1 = minbrk */ 105 ldx [%o1 + %lo(_C_LABEL(__minbrk))], %o1 106 cmp %o1, %o0 /* if (minbrk > %o0) */ 107 movgu %xcc, %o1, %o0 /* %o0 = minbrk */ 108 mov %o0, %o2 /* save argument to syscall */ 109 mov SYS_break, %g1 110 t ST_SYSCALL 111 bcc,a,pt %icc,1f 112 sethi %hi(_C_LABEL(__curbrk)), %g1 113 ERROR() 1141: 115 retl /* success, return 0 & record new break */ 116 stx %o2, [%g1 + %lo(_C_LABEL(__curbrk))] 117 118#endif 119