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;------------------------------------------------------------------------------
;
; Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
; Module Name:
;
;   ZeroMem.nasm
;
; Abstract:
;
;   ZeroMem function
;
; Notes:
;
;------------------------------------------------------------------------------

    DEFAULT REL
    SECTION .text

;------------------------------------------------------------------------------
;  VOID *
;  InternalMemZeroMem (
;    IN VOID   *Buffer,
;    IN UINTN  Count
;    );
;------------------------------------------------------------------------------
global ASM_PFX(InternalMemZeroMem)
ASM_PFX(InternalMemZeroMem):
    push    rdi
    mov     rdi, rcx
    mov     rcx, rdx
    mov     r8, rdi
    and     edx, 7
    shr     rcx, 3
    jz      @ZeroBytes
    pxor    mm0, mm0
.0:
    movntq  [rdi], mm0
    add     rdi, 8
    loop    .0
    mfence
@ZeroBytes:
    xor     eax, eax
    mov     ecx, edx
    rep     stosb
    mov     rax, r8
    pop     rdi
    ret