4748b24d77
2. Fix one bug for GetPowerOfTwo32.c and GetPowerOfTwo64.c, when Operand is 1, 1 should be returned git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@873 6f19259b-4bc3-4df7-8a09-765794883524
41 lines
1.2 KiB
C
41 lines
1.2 KiB
C
/** @file
|
|
Math worker functions.
|
|
|
|
Copyright (c) 2006, 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.
|
|
|
|
**/
|
|
|
|
#include "BaseLibInternals.h"
|
|
|
|
/**
|
|
Returns the value of the highest bit set in a 64-bit value. Equivalent to
|
|
1 << HighBitSet64(x).
|
|
|
|
This function computes the value of the highest bit set in the 64-bit value
|
|
specified by Operand. If Operand is zero, then zero is returned.
|
|
|
|
@param Operand The 64-bit operand to evaluate.
|
|
|
|
@return 1 << HighBitSet64(Operand)
|
|
@retval 0 Operand is zero.
|
|
|
|
**/
|
|
UINT64
|
|
EFIAPI
|
|
GetPowerOfTwo64 (
|
|
IN UINT64 Operand
|
|
)
|
|
{
|
|
INTN BitPos;
|
|
|
|
BitPos = HighBitSet64 (Operand);
|
|
return BitPos >= 0 ? LShiftU64 (1, BitPos) : 0;
|
|
}
|