MdePkg/Library/BaseMemoryLibMmx/Ia32/SetMem.asm

   1 ;------------------------------------------------------------------------------
   2 ;
   3 ; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
   4 ; This program and the accompanying materials
   5 ; are licensed and made available under the terms and conditions of the BSD License
   6 ; which accompanies this distribution.  The full text of the license may be found at
   7 ; http://opensource.org/licenses/bsd-license.php.
   8 ;
   9 ; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 ; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11 ;
  12 ; Module Name:
  13 ;
  14 ;   SetMem.asm
  15 ;
  16 ; Abstract:
  17 ;
  18 ;   SetMem function
  19 ;
  20 ; Notes:
  21 ;
  22 ;------------------------------------------------------------------------------
  23
  24     .686
  25     .model  flat,C
  26     .mmx
  27     .code
  28
  29 ;------------------------------------------------------------------------------
  30 ;  VOID *
  31 ;  EFIAPI
  32 ;  InternalMemSetMem (
  33 ;    IN VOID   *Buffer,
  34 ;    IN UINTN  Count,
  35 ;    IN UINT8  Value
  36 ;    )
  37 ;------------------------------------------------------------------------------
  38 InternalMemSetMem   PROC    USES    edi
  39     mov     al, [esp + 16]
  40     mov     ah, al
  41     shrd    edx, eax, 16
  42     shld    eax, edx, 16
  43     mov     ecx, [esp + 12]             ; ecx <- Count
  44     mov     edi, [esp + 8]              ; edi <- Buffer
  45     mov     edx, ecx
  46     and     edx, 7
  47     shr     ecx, 3                      ; # of Qwords to set
  48     jz      @SetBytes
  49     add     esp, -10h
  50     movq    [esp], mm0                  ; save mm0
  51     movq    [esp + 8], mm1              ; save mm1
  52     movd    mm0, eax
  53     movd    mm1, eax
  54     psllq   mm0, 32
  55     por     mm0, mm1                    ; fill mm0 with 8 Value's
  56 @@:
  57     movq    [edi], mm0
  58     add     edi, 8
  59     loop    @B
  60     movq    mm0, [esp]                  ; restore mm0
  61     movq    mm1, [esp + 8]              ; restore mm1
  62     add     esp, 10h                    ; stack cleanup
  63 @SetBytes:
  64     mov     ecx, edx
  65     rep     stosb
  66     mov     eax, [esp + 8]              ; eax <- Buffer as return value
  67     ret
  68 InternalMemSetMem   ENDP
  69
  70     END