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Diffstat (limited to '')
-rw-r--r-- | src/VBox/ValidationKit/bootsectors/bs3kit/bs3-wc16-U4D.asm | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-wc16-U4D.asm b/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-wc16-U4D.asm new file mode 100644 index 00000000..989ff869 --- /dev/null +++ b/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-wc16-U4D.asm @@ -0,0 +1,124 @@ +; $Id: bs3-wc16-U4D.asm $ +;; @file +; BS3Kit - 16-bit Watcom C/C++, 32-bit unsigned integer division. +; + +; +; Copyright (C) 2007-2023 Oracle and/or its affiliates. +; +; This file is part of VirtualBox base platform packages, as +; available from https://www.virtualbox.org. +; +; This program is free software; you can redistribute it and/or +; modify it under the terms of the GNU General Public License +; as published by the Free Software Foundation, in version 3 of the +; License. +; +; This program is distributed in the hope that it will be useful, but +; WITHOUT ANY WARRANTY; without even the implied warranty of +; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +; General Public License for more details. +; +; You should have received a copy of the GNU General Public License +; along with this program; if not, see <https://www.gnu.org/licenses>. +; +; The contents of this file may alternatively be used under the terms +; of the Common Development and Distribution License Version 1.0 +; (CDDL), a copy of it is provided in the "COPYING.CDDL" file included +; in the VirtualBox distribution, in which case the provisions of the +; CDDL are applicable instead of those of the GPL. +; +; You may elect to license modified versions of this file under the +; terms and conditions of either the GPL or the CDDL or both. +; +; SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0 +; + +%include "bs3kit-template-header.mac" + + + +;; +; 32-bit unsigned integer division. +; +; @returns DX:AX quotient, CX:BX remainder. +; @param DX:AX Dividend. +; @param CX:BX Divisor +; +; @uses Nothing. +; +%ifdef BS3KIT_WITH_REAL_WATCOM_INTRINSIC_NAMES +global __U4D +__U4D: +%endif +global $_?U4D +$_?U4D: +%if TMPL_BITS >= 32 + ; Move dividend into EDX:EAX + shl eax, 10h + mov ax, dx + xor edx, edx + + ; Move divisor into ebx. + shl ebx, 10h + mov bx, cx + + ; Do it! + div ebx + + ; Reminder in to CX:BX + mov bx, dx + shr edx, 10h + mov cx, dx + + ; Quotient into DX:AX + mov edx, eax + shr edx, 10h +%else + push ds + push es + + ; + ; Convert to a C __cdecl call - too lazy to do this in assembly. + ; + + ; Set up a frame of sorts, allocating 8 bytes for the result buffer. + push bp + sub sp, 08h + mov bp, sp + + ; Pointer to the return buffer. + push ss + push bp + add bp, 08h ; Correct bp. + + ; The divisor. + push cx + push bx + + ; The dividend. + push dx + push ax + + BS3_EXTERN_CMN Bs3UInt32Div + call Bs3UInt32Div + + ; Load the reminder. + mov cx, [bp - 08h + 6] + mov bx, [bp - 08h + 4] + ; Load the quotient. + mov dx, [bp - 08h + 2] + mov ax, [bp - 08h] + + mov sp, bp + pop bp + pop es + pop ds + +%endif +%ifdef ASM_MODEL_FAR_CODE + retf +%else + ret +%endif + |