1/* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22/* 23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27/* Copyright (c) 1988 AT&T */ 28/* All Rights Reserved */ 29 30 .file "lsub.s" 31 32/* 33 * Double long subtraction routine. Ported from pdp 11/70 version 34 * with considerable effort. All supplied comments were ported. 35 * Ported from m32 version to sparc. No comments about difficulty. 36 * 37 * dl_t 38 * lsub (lop, rop) 39 * dl_t lop; 40 * dl_t rop; 41 */ 42 43#include "SYS.h" 44 45 ENTRY(lsub) 46 47 ld [%o7+8],%o4 ! Instruction at ret-addr should be a 48 cmp %o4,8 ! 'unimp 8' indicating a valid call. 49 be 1f ! if OK, go forward. 50 nop ! delay instruction. 51 jmp %o7+8 ! return 52 nop ! delay instruction. 53 541: 55 ld [%o0+0],%o2 ! fetch lop.dl_hop 56 ld [%o0+4],%o3 ! fetch lop.dl_lop 57 ld [%o1+0],%o4 ! fetch rop.dl_hop 58 ld [%o1+4],%o5 ! fetch rop.dl_lop 59 subcc %o3,%o5,%o3 ! lop.dl_lop - rop.dl_lop (set carry) 60 subxcc %o2,%o4,%o2 ! lop.dl_hop - rop.dl_hop - <carry> 61 ld [%sp+(16*4)],%o0 ! address to store result into 62 st %o2,[%o0] ! store result.dl_hop 63 jmp %o7+12 ! return 64 st %o3,[%o0+4] ! store result.dl_lop 65 66 SET_SIZE(lsub) 67