1/* $OpenBSD: sbrk.S,v 1.15 2023/12/10 16:45:51 deraadt 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 43__curbrk: 44 .long _end 45 END(__curbrk) 46 .type __curbrk,@object 47 48 .text 49 50 .weak sbrk 51 52ENTRY(sbrk) 53#ifdef __PIC__ 54 PIC_SAVE(%r9) 55 PIC_SETUP 56#endif 57 58#ifdef __PIC__ 59 PIC_LOAD(%r5,__curbrk) 60#else 61 or.u %r5,%r0,%hi16(__curbrk) 62 ld %r5,%r5,%lo16(__curbrk) 63#endif 64 add %r2,%r2,%r5 65 or %r4,%r2,0 66 or %r13,%r0,SYS_break 6799: tb0 0,%r0,450 68 PINSYSCALL(SYS_break, 99b) 69#ifdef __PIC__ 70 br 9f 71#else 72 br CERROR 73#endif 74 /* Save old __curbrk */ 75#ifdef __PIC__ 76 PIC_LOAD(%r2,__curbrk) 77#else 78 or.u %r5,%r0,%hi16(__curbrk) 79 ld %r2,%r5,%lo16(__curbrk) 80#endif 81 /* Update __curbrk */ 82#ifdef __PIC__ 83 PIC_STORE(%r4,__curbrk) 84#else 85 st %r4,%r5,%lo16(__curbrk) 86#endif 87 /* and return old __curbrk */ 88#ifdef __PIC__ 89 PIC_RESTORE(%r9) 90#endif 91 jmp.n %r1 92 or %r3,%r0,0 93 94#ifdef __PIC__ 959: 96 br.n CERROR 97 PIC_RESTORE(%r9) 98#endif 99END(sbrk) 100