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, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22/* Copyright (c) 1988 AT&T */ 23/* All Rights Reserved */ 24 25 26/* Copyright (c) 1989 by Sun Microsystems, Inc. */ 27 28.ident "%Z%%M% %I% %E% SMI" /* SVr4.0 1.1 */ 29 30/* 31 * Double long subtraction routine. Ported from pdp 11/70 version 32 * with considerable effort. All supplied comments were ported. 33 * Ported from m32 version to sparc. No comments about difficulty. 34 * 35 * dl_t 36 * lsub (lop, rop) 37 * dl_t lop; 38 * dl_t rop; 39 */ 40 41 .file "lsub.s" 42 43#include <sys/asm_linkage.h> 44 45 ANSI_PRAGMA_WEAK(lsub,function) 46 47#include "synonyms.h" 48 49 ENTRY(lsub) 50 51 ld [%o7+8],%o4 ! Instruction at ret-addr should be a 52 cmp %o4,8 ! 'unimp 8' indicating a valid call. 53 be 1f ! if OK, go forward. 54 nop ! delay instruction. 55 jmp %o7+8 ! return 56 nop ! delay instruction. 57 581: 59 ld [%o0+0],%o2 ! fetch lop.dl_hop 60 ld [%o0+4],%o3 ! fetch lop.dl_lop 61 ld [%o1+0],%o4 ! fetch rop.dl_hop 62 ld [%o1+4],%o5 ! fetch rop.dl_lop 63 subcc %o3,%o5,%o3 ! lop.dl_lop - rop.dl_lop (set carry) 64 subxcc %o2,%o4,%o2 ! lop.dl_hop - rop.dl_hop - <carry> 65 ld [%sp+(16*4)],%o0 ! address to store result into 66 st %o2,[%o0] ! store result.dl_hop 67 jmp %o7+12 ! return 68 st %o3,[%o0+4] ! store result.dl_lop 69 70 SET_SIZE(lsub) 71