audk/MdePkg/Library/BaseLib/Ia32/MultU64x32.c

48 lines
1.4 KiB
C

/** @file
Calculate the product of a 64-bit integer and a 32-bit integer
Copyright (c) 2006 - 2008, Intel Corporation<BR>
All rights reserved. This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
/**
Multiples a 64-bit unsigned integer by a 32-bit unsigned integer
and generates a 64-bit unsigned result.
This function multiples the 64-bit unsigned value Multiplicand by the 32-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 32-bit unsigned value.
@return Multiplicand * Multiplier
**/
UINT64
EFIAPI
InternalMathMultU64x32 (
IN UINT64 Multiplicand,
IN UINT32 Multiplier
)
{
_asm {
mov ecx, Multiplier
mov eax, ecx
imul ecx, dword ptr [Multiplicand + 4] // overflow not detectable
mul dword ptr [Multiplicand + 0]
add edx, ecx
}
}