;; @file

; innotek Portable Runtime - ASMAtomicBitTestAndToggle().

;

;

; 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

;;

; Atomically tests and toggles a bit in a bitmap.

;

; @returns al(rax) true if the bit was set.

; @returns al(rax) false if the bit was clear.

; @param rcx pvBitmap Pointer to the bitmap.

; @param edx iBit The bit to test and toggle.

BEGINPROC_EXPORTED ASMAtomicBitTestAndToggle

lock btc [rcx], edx

sbb eax, eax

ret

ENDPROC ASMAtomicBitTestAndToggle