EdkCompatibilityPkg/Foundation/Library/CompilerStub/Ia32/memset.asm

   1 ;------------------------------------------------------------------------------
   2 ;
   3 ; Copyright (c) 2007, Intel Corporation
   4 ; All rights reserved. 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 ;   memset function
  19 ;
  20 ; Notes:
  21 ;
  22 ;------------------------------------------------------------------------------
  23
  24     .686
  25     .model  flat,C
  26     .mmx
  27     .code
  28
  29 ;------------------------------------------------------------------------------
  30 ;  VOID *
  31 ;  memset (
  32 ;    OUT VOID   *Buffer,
  33 ;    IN  UINT8  Value,
  34 ;    IN  UINTN  Count
  35 ;    )
  36 ;------------------------------------------------------------------------------
  37 memset   PROC    USES    edi
  38     mov     al, [esp + 12]
  39     mov     ah, al
  40     shrd    edx, eax, 16
  41     shld    eax, edx, 16
  42     mov     ecx, [esp + 16]             ; ecx <- Count
  43     cmp     ecx, 0                      ; if Count == 0, do nothing
  44     je      @SetDone
  45     mov     edi, [esp + 8]              ; edi <- Buffer
  46     mov     edx, ecx
  47     and     edx, 7
  48     shr     ecx, 3                      ; # of Qwords to set
  49     jz      @SetBytes
  50     add     esp, -10h
  51     movq    [esp], mm0                  ; save mm0
  52     movq    [esp + 8], mm1              ; save mm1
  53     movd    mm0, eax
  54     movd    mm1, eax
  55     psllq   mm0, 32
  56     por     mm0, mm1                    ; fill mm0 with 8 Value's
  57 @@:
  58     movq    [edi], mm0
  59     add     edi, 8
  60     loop    @B
  61     movq    mm0, [esp]                  ; restore mm0
  62     movq    mm1, [esp + 8]              ; restore mm1
  63     add     esp, 10h                    ; stack cleanup
  64 @SetBytes:
  65     mov     ecx, edx
  66     rep     stosb
  67 @SetDone:
  68     mov     eax, [esp + 8]              ; eax <- Buffer as return value
  69     ret
  70 memset   ENDP
  71
  72     END