MdePkg/Library/BaseLib/Ia32/MultU64x64.c

/** @file
  Calculate the product of a 64-bit integer and another 64-bit integer

  Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>
  SPDX-License-Identifier: BSD-2-Clause-Patent

**/

/**
  Multiplies a 64-bit unsigned integer by a 64-bit unsigned integer
  and generates a 64-bit unsigned result.

  This function multiplies the 64-bit unsigned value Multiplicand by the 64-bit
  unsigned value Multiplier and generates a 64-bit unsigned result. This 64-
  bit unsigned result is returned.

  @param  Multiplicand  A 64-bit unsigned value.
  @param  Multiplier    A 64-bit unsigned value.

  @return Multiplicand * Multiplier

**/
UINT64
EFIAPI
InternalMathMultU64x64 (
  IN      UINT64  Multiplicand,
  IN      UINT64  Multiplier
  )
{
  _asm {
    mov     ebx, dword ptr [Multiplicand + 0]
    mov     edx, dword ptr [Multiplier + 0]
    mov     ecx, ebx
    mov     eax, edx
    imul    ebx, dword ptr [Multiplier + 4]
    imul    edx, dword ptr [Multiplicand + 4]
    add     ebx, edx
    mul     ecx
    add     edx, ebx
  }
}