17c478bd9Sstevel@tonic-gate/* 27c478bd9Sstevel@tonic-gate * CDDL HEADER START 37c478bd9Sstevel@tonic-gate * 47c478bd9Sstevel@tonic-gate * The contents of this file are subject to the terms of the 5*9a70fc3bSMark J. Nelson * Common Development and Distribution License (the "License"). 6*9a70fc3bSMark J. Nelson * You may not use this file except in compliance with the License. 77c478bd9Sstevel@tonic-gate * 87c478bd9Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 97c478bd9Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing. 107c478bd9Sstevel@tonic-gate * See the License for the specific language governing permissions 117c478bd9Sstevel@tonic-gate * and limitations under the License. 127c478bd9Sstevel@tonic-gate * 137c478bd9Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each 147c478bd9Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 157c478bd9Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the 167c478bd9Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying 177c478bd9Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner] 187c478bd9Sstevel@tonic-gate * 197c478bd9Sstevel@tonic-gate * CDDL HEADER END 207c478bd9Sstevel@tonic-gate */ 217c478bd9Sstevel@tonic-gate/* 227c478bd9Sstevel@tonic-gate * Copyright 2004 Sun Microsystems, Inc. All rights reserved. 237c478bd9Sstevel@tonic-gate * Use is subject to license terms. 247c478bd9Sstevel@tonic-gate */ 257c478bd9Sstevel@tonic-gate 26*9a70fc3bSMark J. Nelson .file "_mul64.s" 277c478bd9Sstevel@tonic-gate 287c478bd9Sstevel@tonic-gate/ 297c478bd9Sstevel@tonic-gate/ function __mul64(A,B:Longint):Longint; 307c478bd9Sstevel@tonic-gate/ {Overflow is not checked} 317c478bd9Sstevel@tonic-gate/ 327c478bd9Sstevel@tonic-gate/ We essentially do multiply by longhand, using base 2**32 digits. 337c478bd9Sstevel@tonic-gate/ a b parameter A 347c478bd9Sstevel@tonic-gate/ x c d parameter B 357c478bd9Sstevel@tonic-gate/ --------- 367c478bd9Sstevel@tonic-gate/ ad bd 377c478bd9Sstevel@tonic-gate/ ac bc 387c478bd9Sstevel@tonic-gate/ ----------------- 397c478bd9Sstevel@tonic-gate/ ac ad+bc bd 407c478bd9Sstevel@tonic-gate/ 417c478bd9Sstevel@tonic-gate/ We can ignore ac and top 32 bits of ad+bc: if <> 0, overflow happened. 427c478bd9Sstevel@tonic-gate/ 437c478bd9Sstevel@tonic-gate 447c478bd9Sstevel@tonic-gate#include "SYS.h" 457c478bd9Sstevel@tonic-gate 467c478bd9Sstevel@tonic-gate ENTRY(__mul64) 477c478bd9Sstevel@tonic-gate push %ebp 487c478bd9Sstevel@tonic-gate mov %esp,%ebp 497c478bd9Sstevel@tonic-gate pushl %esi 507c478bd9Sstevel@tonic-gate mov 12(%ebp),%eax / A.hi (a) 517c478bd9Sstevel@tonic-gate mull 16(%ebp) / Multiply A.hi by B.lo (produces ad) 527c478bd9Sstevel@tonic-gate xchg %ecx,%eax / ecx = bottom half of ad. 537c478bd9Sstevel@tonic-gate movl 8(%ebp),%eax / A.Lo (b) 547c478bd9Sstevel@tonic-gate movl %eax,%esi / Save A.lo for later 557c478bd9Sstevel@tonic-gate mull 16(%ebp) / Multiply A.Lo by B.LO (dx:ax = bd.) 567c478bd9Sstevel@tonic-gate addl %edx,%ecx / cx is ad 577c478bd9Sstevel@tonic-gate xchg %eax,%esi / esi is bd, eax = A.lo (d) 587c478bd9Sstevel@tonic-gate mull 20(%ebp) / Multiply A.lo * B.hi (producing bc) 597c478bd9Sstevel@tonic-gate addl %ecx,%eax / Produce ad+bc 607c478bd9Sstevel@tonic-gate movl %esi,%edx 617c478bd9Sstevel@tonic-gate xchg %eax,%edx 627c478bd9Sstevel@tonic-gate popl %esi 637c478bd9Sstevel@tonic-gate movl %ebp,%esp 647c478bd9Sstevel@tonic-gate popl %ebp 657c478bd9Sstevel@tonic-gate ret $16 667c478bd9Sstevel@tonic-gate SET_SIZE(__mul64) 67