MdePkg/Library/BaseMemoryLibSse2/Ia32/ZeroMem.s

   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     .xmm:
  27     .code:
  28
  29 #------------------------------------------------------------------------------
  30 #  VOID *
  31 #  _mem_ZeroMem (
  32 #    IN VOID   *Buffer,
  33 #    IN UINTN  Count
  34 #    )
  35 #------------------------------------------------------------------------------
  36 .global _InternalMemZeroMem
  37 _InternalMemZeroMem:
  38     push    %edi
  39     movl    8(%esp), %edi
  40     movl    12(%esp), %edx
  41     xorl    %ecx, %ecx
  42     subl    %edi, %ecx
  43     xorl    %eax, %eax
  44     andl    $15, %ecx
  45     jz      L0
  46     cmpl    %edx, %ecx
  47     cmova   %edx, %ecx
  48     subl    %ecx, %edx
  49     rep
  50     stosb
  51 L0:
  52     movl    %edx, %ecx
  53     andl    $15, %edx
  54     shrl    $4, %ecx
  55     jz      @ZeroBytes
  56     pxor    %xmm0, %xmm0
  57 L1:
  58     movntdq %xmm0, (%edi)
  59     addl    $16, %edi
  60     loop    L1
  61     mfence
  62 @ZeroBytes:
  63     movl    %edx, %ecx
  64     rep
  65     stosb
  66     movl    8(%esp), %eax
  67     pop     %edi
  68     ret