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;------------------------------------------------------------------------------
;
; Copyright (c) 2007, 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:
;
; memset function
;
; Notes:
;
;------------------------------------------------------------------------------
.686
.model flat,C
.mmx
.code
;------------------------------------------------------------------------------
; VOID *
; memset (
; OUT VOID *Buffer,
; IN UINT8 Value,
; IN UINTN Count
; )
;------------------------------------------------------------------------------
memset PROC USES edi
mov al, [esp + 12]
mov ah, al
shrd edx, eax, 16
shld eax, edx, 16
mov ecx, [esp + 16] ; ecx <- Count
cmp ecx, 0 ; if Count == 0, do nothing
je @SetDone
mov edi, [esp + 8] ; edi <- Buffer
mov edx, ecx
and edx, 7
shr ecx, 3 ; # of Qwords to set
jz @SetBytes
add esp, -10h
movq [esp], mm0 ; save mm0
movq [esp + 8], mm1 ; save mm1
movd mm0, eax
movd mm1, eax
psllq mm0, 32
por mm0, mm1 ; fill mm0 with 8 Value's
@@:
movq [edi], mm0
add edi, 8
loop @B
movq mm0, [esp] ; restore mm0
movq mm1, [esp + 8] ; restore mm1
add esp, 10h ; stack cleanup
@SetBytes:
mov ecx, edx
rep stosb
@SetDone:
mov eax, [esp + 8] ; eax <- Buffer as return value
ret
memset ENDP
END
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