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diff --git a/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-cmn-RegGetTr.asm b/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-cmn-RegGetTr.asm
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+++ b/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-cmn-RegGetTr.asm
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+; $Id: bs3-cmn-RegGetTr.asm $
+;; @file
+; BS3Kit - Bs3RegGetTr
+;
+
+;
+; Copyright (C) 2007-2019 Oracle Corporation
+;
+; This file is part of VirtualBox Open Source Edition (OSE), as
+; available from http://www.virtualbox.org. This file is free software;
+; you can redistribute it and/or modify it under the terms of the GNU
+; General Public License (GPL) as published by the Free Software
+; Foundation, in version 2 as it comes in the "COPYING" file of the
+; VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+; hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+;
+; The contents of this file may alternatively be used under the terms
+; of the Common Development and Distribution License Version 1.0
+; (CDDL) only, as it comes in the "COPYING.CDDL" file of the
+; VirtualBox OSE 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.
+;
+
+%include "bs3kit-template-header.mac"
+
+
+BS3_EXTERN_CMN Bs3Syscall
+%if TMPL_BITS == 16
+BS3_EXTERN_DATA16 g_bBs3CurrentMode
+%endif
+BS3_EXTERN_SYSTEM16 Bs3Gdt
+TMPL_BEGIN_TEXT
+
+
+;;
+; @cproto BS3_CMN_PROTO_STUB(uint16_t, Bs3RegGetTr,(void));
+;
+; @returns The LDTR value.
+
+; @remarks Does not require 20h of parameter scratch space in 64-bit mode.
+;
+; @uses No GPRs.
+;
+BS3_PROC_BEGIN_CMN Bs3RegGetTr, BS3_PBC_HYBRID_SAFE
+ BS3_CALL_CONV_PROLOG 0
+ push xBP
+ mov xBP, xSP
+
+%if TMPL_BITS == 16
+ ; If V8086 mode we have to go thru a syscall.
+ test byte [BS3_DATA16_WRT(g_bBs3CurrentMode)], BS3_MODE_CODE_V86
+ jnz .via_system_call
+%endif
+ ; Load it.
+ str ax
+ jmp .return
+
+.via_system_call:
+ mov ax, BS3_SYSCALL_GET_TR
+ call Bs3Syscall
+
+.return:
+ pop xBP
+ BS3_CALL_CONV_EPILOG 0
+ BS3_HYBRID_RET
+BS3_PROC_END_CMN Bs3RegGetTr
+