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diff --git a/src/VBox/Runtime/common/math/watcom/U8RS-x86-32.asm b/src/VBox/Runtime/common/math/watcom/U8RS-x86-32.asm
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+; $Id: U8RS-x86-32.asm $
+;; @file
+; BS3Kit - 32-bit Watcom C/C++, 64-bit unsigned integer right shift.
+;
+
+;
+; 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 "iprt/asmdefs.mac"
+
+
+BEGINCODE
+
+
+;;
+; 64-bit unsigned integer right shift.
+;
+; @returns EDX:EAX
+; @param EDX:EAX Value to shift.
+; @param BL Shift count (it's specified as ECX:EBX, but we only use BL).
+;
+global __U8RS
+__U8RS:
+ push ecx ; We're allowed to trash ECX, but why bother.
+
+ mov cl, bl
+ and cl, 3fh
+ test cl, 20h
+ jnz .big_shift
+
+ ; Shifting less than 32.
+ shrd eax, edx, cl
+ shr edx, cl
+
+.return:
+ pop ecx
+ ret
+
+.big_shift:
+ ; Shifting 32 or more.
+ mov eax, edx
+ shr eax, cl ; Only uses lower 5 bits.
+ xor edx, edx
+ jmp .return
+