MdePkg/Library/BaseMemoryLibMmx/Ia32/ZeroMem.asm

   1 ;------------------------------------------------------------------------------
   2 ;
   3 ; Copyright (c) 2006, 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 ;   ZeroMem.asm
  15 ;
  16 ; Abstract:
  17 ;
  18 ;   ZeroMem function
  19 ;
  20 ; Notes:
  21 ;
  22 ;------------------------------------------------------------------------------
  23
  24     .686
  25     .model  flat,C
  26     .mmx
  27     .code
  28
  29 ;------------------------------------------------------------------------------
  30 ;  VOID *
  31 ;  InternalMemZeroMem (
  32 ;    IN VOID   *Buffer,
  33 ;    IN UINTN  Count
  34 ;    );
  35 ;------------------------------------------------------------------------------
  36 InternalMemZeroMem  PROC    USES    edi
  37     mov     edi, [esp + 8]
  38     mov     ecx, [esp + 12]
  39     mov     edx, ecx
  40     shr     ecx, 3
  41     jz      @ZeroBytes
  42     pxor    mm0, mm0
  43 @@:
  44     movq    [edi], mm0
  45     add     edi, 8
  46     loop    @B
  47 @ZeroBytes:
  48     and     edx, 7
  49     xor     eax, eax
  50     mov     ecx, edx
  51     rep     stosb
  52     mov     eax, [esp + 8]
  53     ret
  54 InternalMemZeroMem  ENDP
  55
  56     END