;; @file

; IPRT - ASMAtomicBitClear().

;

;

; Copyright (C) 2006-2007 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

;;

; Atomically clears a bit in a bitmap.

;

; @param rcx pvBitmap Pointer to the bitmap.

; @param edx iBit The bit to toggle set.

; @remark No memory barrier, take care on smp.

;

BEGINPROC_EXPORTED ASMAtomicBitClear

lock btr [rcx], edx

ret

ENDPROC ASMAtomicBitClear