;; @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. ;******************************************************************************* ;* 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