MdePkg/Library/BaseLib/Ia32/MultU64x64.c

   1 /** @file
   2   Calculate the product of a 64-bit integer and another 64-bit integer
   3
   4   Copyright (c) 2006 - 2007, Intel Corporation<BR>
   5   All rights reserved. This program and the accompanying materials
   6   are licensed and made available under the terms and conditions of the BSD License
   7   which accompanies this distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 //
  16 // Include common header file for this module.
  17 //
  18 #include "CommonHeader.h"
  19
  20 UINT64
  21 EFIAPI
  22 InternalMathMultU64x64 (
  23   IN      UINT64                    Multiplicand,
  24   IN      UINT64                    Multiplier
  25   )
  26 {
  27   _asm {
  28     mov     ebx, dword ptr [Multiplicand + 0]
  29     mov     edx, dword ptr [Multiplier + 0]
  30     mov     ecx, ebx
  31     mov     eax, edx
  32     imul    ebx, dword ptr [Multiplier + 4]
  33     imul    edx, dword ptr [Multiplicand + 4]
  34     add     ebx, edx
  35     mul     ecx
  36     add     edx, ebx
  37   }
  38 }
  39