MdePkg/Library/BaseMemoryLibMmx/X64/CompareMem.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 ;   CompareMem.Asm
  15 ;
  16 ; Abstract:
  17 ;
  18 ;   CompareMem function
  19 ;
  20 ; Notes:
  21 ;
  22 ;   The following BaseMemoryLib instances share the same version of this file:
  23 ;
  24 ;       BaseMemoryLibRepStr
  25 ;       BaseMemoryLibMmx
  26 ;       BaseMemoryLibSse2
  27 ;
  28 ;------------------------------------------------------------------------------
  29
  30     .code
  31
  32 ;------------------------------------------------------------------------------
  33 ; INTN
  34 ; EFIAPI
  35 ; InternalMemCompareMem (
  36 ;   IN      CONST VOID                *DestinationBuffer,
  37 ;   IN      CONST VOID                *SourceBuffer,
  38 ;   IN      UINTN                     Length
  39 ;   );
  40 ;------------------------------------------------------------------------------
  41 InternalMemCompareMem   PROC    USES    rsi rdi
  42     mov     rsi, rcx
  43     mov     rdi, rdx
  44     mov     rcx, r8
  45     repe    cmpsb
  46     movzx   rax, byte ptr [rsi - 1]
  47     movzx   rdx, byte ptr [rdi - 1]
  48     sub     rax, rdx
  49     ret
  50 InternalMemCompareMem   ENDP
  51
  52     END