ASMProbeReadByte.asm revision de8e40551b020624bc0683e5905f06b51f3ceebe
;; @file
; innotek Portable Runtime - ASMProbeReadByte().
;
;
; Copyright (C) 2006-2007 innotek GmbH
;
; 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 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.
;
; If you received this file as part of a commercial VirtualBox
; distribution, then only the terms of your commercial VirtualBox
; license agreement apply instead of the previous paragraph.
;
;*******************************************************************************
;* 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