1/* $OpenBSD: brk.S,v 1.12 2013/01/24 05:24:47 miod 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 * the Systems Programming Group of the University of Utah Computer 9 * Science Department. 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 36#include "SYS.h" 37 38 .globl _end 39 .globl __curbrk 40 41 .data 42 .align 8 43ASGLOBAL(__minbrk) 44 .long _end 45 46ENTRY(brk) 47#ifdef __PIC__ 48 PIC_SAVE(%r9) 49 PIC_SETUP 50#endif 51 52#ifdef __PIC__ 53 PIC_LOAD(%r5,__minbrk) 54#else 55 or.u %r5,%r0,%hi16(__minbrk) 56 ld %r5,%r5,%lo16(__minbrk) 57#endif 58 cmp %r3,%r5,%r2 59 bb1 ls,%r3,1f /* r2 should be > minbrk; can't go below end */ 60 or %r2,%r5,0 /* otherwise, set r2 to minbrk */ 611: 62 or %r4,%r2,0 63 or %r13,%r0,__SYSCALLNAME(SYS_,break) 64 tb0 0,%r0,450 65#ifdef __PIC__ 66 br 9f 67#else 68 br CERROR 69#endif 70 71#ifdef __PIC__ 72 PIC_STORE(%r4,__curbrk) 73#else 74 or.u %r5,%r0,%hi16(__curbrk) 75 st %r4,%r5,%lo16(__curbrk) 76#endif 77 or %r2,%r0,0 /* clear r2/r3 to indicate success */ 78#ifdef __PIC__ 79 PIC_RESTORE(%r9) 80#endif 81 jmp.n %r1 82 or %r3,%r0,0 83 84#ifdef __PIC__ 859: 86 br.n CERROR 87 PIC_RESTORE(%r9) 88#endif 89END(brk) 90