1*5d9d9091SRichard Lowe/* 2*5d9d9091SRichard Lowe * CDDL HEADER START 3*5d9d9091SRichard Lowe * 4*5d9d9091SRichard Lowe * The contents of this file are subject to the terms of the 5*5d9d9091SRichard Lowe * Common Development and Distribution License (the "License"). 6*5d9d9091SRichard Lowe * You may not use this file except in compliance with the License. 7*5d9d9091SRichard Lowe * 8*5d9d9091SRichard Lowe * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9*5d9d9091SRichard Lowe * or http://www.opensolaris.org/os/licensing. 10*5d9d9091SRichard Lowe * See the License for the specific language governing permissions 11*5d9d9091SRichard Lowe * and limitations under the License. 12*5d9d9091SRichard Lowe * 13*5d9d9091SRichard Lowe * When distributing Covered Code, include this CDDL HEADER in each 14*5d9d9091SRichard Lowe * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15*5d9d9091SRichard Lowe * If applicable, add the following below this CDDL HEADER, with the 16*5d9d9091SRichard Lowe * fields enclosed by brackets "[]" replaced with your own identifying 17*5d9d9091SRichard Lowe * information: Portions Copyright [yyyy] [name of copyright owner] 18*5d9d9091SRichard Lowe * 19*5d9d9091SRichard Lowe * CDDL HEADER END 20*5d9d9091SRichard Lowe */ 21*5d9d9091SRichard Lowe/* 22*5d9d9091SRichard Lowe * Copyright 2004 Sun Microsystems, Inc. All rights reserved. 23*5d9d9091SRichard Lowe * Use is subject to license terms. 24*5d9d9091SRichard Lowe */ 25*5d9d9091SRichard Lowe 26*5d9d9091SRichard Lowe .file "_mul64.s" 27*5d9d9091SRichard Lowe 28*5d9d9091SRichard Lowe/ 29*5d9d9091SRichard Lowe/ function __mul64(A,B:Longint):Longint; 30*5d9d9091SRichard Lowe/ {Overflow is not checked} 31*5d9d9091SRichard Lowe/ 32*5d9d9091SRichard Lowe/ We essentially do multiply by longhand, using base 2**32 digits. 33*5d9d9091SRichard Lowe/ a b parameter A 34*5d9d9091SRichard Lowe/ x c d parameter B 35*5d9d9091SRichard Lowe/ --------- 36*5d9d9091SRichard Lowe/ ad bd 37*5d9d9091SRichard Lowe/ ac bc 38*5d9d9091SRichard Lowe/ ----------------- 39*5d9d9091SRichard Lowe/ ac ad+bc bd 40*5d9d9091SRichard Lowe/ 41*5d9d9091SRichard Lowe/ We can ignore ac and top 32 bits of ad+bc: if <> 0, overflow happened. 42*5d9d9091SRichard Lowe/ 43*5d9d9091SRichard Lowe 44*5d9d9091SRichard Lowe#include "SYS.h" 45*5d9d9091SRichard Lowe 46*5d9d9091SRichard Lowe ENTRY(__mul64) 47*5d9d9091SRichard Lowe push %ebp 48*5d9d9091SRichard Lowe mov %esp,%ebp 49*5d9d9091SRichard Lowe pushl %esi 50*5d9d9091SRichard Lowe mov 12(%ebp),%eax / A.hi (a) 51*5d9d9091SRichard Lowe mull 16(%ebp) / Multiply A.hi by B.lo (produces ad) 52*5d9d9091SRichard Lowe xchg %ecx,%eax / ecx = bottom half of ad. 53*5d9d9091SRichard Lowe movl 8(%ebp),%eax / A.Lo (b) 54*5d9d9091SRichard Lowe movl %eax,%esi / Save A.lo for later 55*5d9d9091SRichard Lowe mull 16(%ebp) / Multiply A.Lo by B.LO (dx:ax = bd.) 56*5d9d9091SRichard Lowe addl %edx,%ecx / cx is ad 57*5d9d9091SRichard Lowe xchg %eax,%esi / esi is bd, eax = A.lo (d) 58*5d9d9091SRichard Lowe mull 20(%ebp) / Multiply A.lo * B.hi (producing bc) 59*5d9d9091SRichard Lowe addl %ecx,%eax / Produce ad+bc 60*5d9d9091SRichard Lowe movl %esi,%edx 61*5d9d9091SRichard Lowe xchg %eax,%edx 62*5d9d9091SRichard Lowe popl %esi 63*5d9d9091SRichard Lowe movl %ebp,%esp 64*5d9d9091SRichard Lowe popl %ebp 65*5d9d9091SRichard Lowe ret $16 66*5d9d9091SRichard Lowe SET_SIZE(__mul64) 67