1/* $OpenBSD: sbrk.S,v 1.3 2020/07/27 05:08:57 gkoehler Exp $ */ 2 3/* 4 * Copyright (c) 1996 Dale Rahn 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 16 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 19 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28#include "SYS.h" 29 30 .data 31 .globl _end 32 .globl __curbrk 33 .hidden __curbrk 34__curbrk: 35 .quad _end 36 END(__curbrk) 37 .type __curbrk,@object 38 39 .weak sbrk 40 41 .text 42PSEUDO_PREFIX(,sbrk,break) 43 /* call break(__curbrk + size) */ 44 addis %r6, %r2, __curbrk@toc@ha 45 addi %r6, %r6, __curbrk@toc@l /* # %r6 = &__curbrk */ 46 47 ld %r5, 0(%r6) /* # %r5 = *%r6 (old_curbrk) */ 48 add %r3, %r5, %r3 /* # %r3 = new_curbrk */ 49 mr %r7, %r3 50 51 sc 52 53 /* check for error */ 54 cmpwi %r0, 0 55 beq+ .L_sbrk_ok 56 stw %r0, R13_OFFSET_ERRNO(%r13) 57 li %r3, -1 58 blr 59 60 /* update, __curbrk and return */ 61.L_sbrk_ok: 62 std %r7, 0(%r6) /* # remember, %r6=&__curbrk, %r7=new_curbrk */ 63 mr %r3, %r5 /* # remember, %r5=old_curbrk */ 64 blr 65END(sbrk) 66