;; @file

; IPRT - ASMProbeReadByte().

;

;

; Copyright (C) 2006-2010 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