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;------------------------------------------------------------------------------
;
; Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
; Module Name:
;
;   InterlockedDecrement.Asm
;
; Abstract:
;
;   InterlockedDecrement function
;
; Notes:
;
;------------------------------------------------------------------------------

    DEFAULT REL
    SECTION .text

;------------------------------------------------------------------------------
; UINT32
; EFIAPI
; InternalSyncDecrement (
;   IN      volatile UINT32           *Value
;   );
;------------------------------------------------------------------------------
global ASM_PFX(InternalSyncDecrement)
ASM_PFX(InternalSyncDecrement):
    mov       eax, 0FFFFFFFFh
    lock xadd dword [rcx], eax
    dec       eax
    ret