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;; @file
; IPRT - ASMProbeReadByte().
;
;
; Copyright (C) 2006-2019 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.
;
;*******************************************************************************
;* 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.
BEGINPROC_EXPORTED ASMProbeReadByte
mov al, [rcx]
ret
ENDPROC ASMProbeReadByte
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