MdePkg/Library/BaseMemoryLibMmx/X64/SetMem64.nasm

;------------------------------------------------------------------------------
;
; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
; Module Name:
;
;   SetMem64.nasm
;
; Abstract:
;
;   SetMem64 function
;
; Notes:
;
;------------------------------------------------------------------------------

    DEFAULT REL
    SECTION .text

;------------------------------------------------------------------------------
;  VOID *
;  InternalMemSetMem64 (
;    IN VOID   *Buffer,
;    IN UINTN  Count,
;    IN UINT64 Value
;    )
;------------------------------------------------------------------------------
global ASM_PFX(InternalMemSetMem64)
ASM_PFX(InternalMemSetMem64):
    DB      0x49, 0xf, 0x6e, 0xc0         ; movd mm0, r8 (Value)
    mov     rax, rcx                    ; rax <- Buffer
    xchg    rcx, rdx                    ; rcx <- Count
.0:
    DB      0xf, 0xe7, 0x2              ; movntq  [rdx], mm0
    add     rdx, 8
    loop    .0
    mfence
    ret