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;------------------------------------------------------------------------------
;
; Copyright (c) 2006, 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
xor rcx, rcx
xor eax, eax
sub rcx, rdi
and rcx, 15
mov r8, rdi
jz .0
cmp rcx, rdx
cmova rcx, rdx
sub rdx, rcx
rep stosb
.0:
mov rcx, rdx
and edx, 15
shr rcx, 4
jz @ZeroBytes
pxor xmm0, xmm0
.1:
movntdq [rdi], xmm0 ; rdi should be 16-byte aligned
add rdi, 16
loop .1
mfence
@ZeroBytes:
mov ecx, edx
rep stosb
mov rax, r8
pop rdi
ret
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