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diff --git a/src/VBox/Runtime/win/amd64/ASMProbeReadByte.asm b/src/VBox/Runtime/win/amd64/ASMProbeReadByte.asm
new file mode 100644
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+++ b/src/VBox/Runtime/win/amd64/ASMProbeReadByte.asm
@@ -0,0 +1,58 @@
+;; @file
+; IPRT - ASMProbeReadByte().
+;
+
+;
+; Copyright (C) 2006-2023 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
+;
+
+;*******************************************************************************
+;* Header Files                                                                *
+;*******************************************************************************
+%include "iprt/asmdefs.mac"
+
+BEGINCODE
+
+;;
+; Probes a byte pointer for read access.
+;
+; While the function will not fault if the byte is not read accessible,
+; the idea is to do this in a safe place like before acquiring locks
+; and such like.
+;
+; Also, this functions guarantees that an eager compiler is not going
+; to optimize the probing away.
+;
+; @param   rcx  pvByte      Pointer to the byte.
+RT_BEGINPROC ASMProbeReadByte
+        mov     al, [rcx]
+        ret
+ENDPROC ASMProbeReadByte
+