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//
// Include common header file for this module.
//
#include "CommonHeader.h"
;------------------------------------------------------------------------------
;
; Copyright (c) 2006, Intel Corporation
; All rights reserved. This program and the accompanying materials
; are licensed and made available under the terms and conditions of the BSD License
; which accompanies this distribution. The full text of the license may be found at
; http://opensource.org/licenses/bsd-license.php
;
; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
;
; Module Name:
;
; SetMem.asm
;
; Abstract:
;
; SetMem function
;
; Notes:
;
;------------------------------------------------------------------------------
.686
.model flat,C
.xmm
.code
;------------------------------------------------------------------------------
; VOID *
; EFIAPI
; InternalMemSetMem (
; IN VOID *Buffer,
; IN UINTN Count,
; IN UINT8 Value
; );
;------------------------------------------------------------------------------
InternalMemSetMem PROC USES edi
mov edx, [esp + 12] ; edx <- Count
mov edi, [esp + 8] ; edi <- Buffer
mov al, [esp + 16] ; al <- Value
xor ecx, ecx
sub ecx, edi
and ecx, 15 ; ecx + edi aligns on 16-byte boundary
jz @F
cmp ecx, edx
cmova ecx, edx
sub edx, ecx
rep stosb
@@:
mov ecx, edx
and edx, 15
shr ecx, 4 ; ecx <- # of DQwords to set
jz @SetBytes
mov ah, al ; ax <- Value | (Value << 8)
add esp, -16
movdqu [esp], xmm0 ; save xmm0
movd xmm0, eax
pshuflw xmm0, xmm0, 0 ; xmm0[0..63] <- Value repeats 8 times
movlhps xmm0, xmm0 ; xmm0 <- Value repeats 16 times
@@:
movntdq [edi], xmm0 ; edi should be 16-byte aligned
add edi, 16
loop @B
mfence
movdqu xmm0, [esp] ; restore xmm0
add esp, 16 ; stack cleanup
@SetBytes:
mov ecx, edx
rep stosb
mov eax, [esp + 8] ; eax <- Buffer as return value
ret
InternalMemSetMem ENDP
END
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