CloverBootloader/MdePkg/Library/BaseLib/GetPowerOfTwo64.c
2019-09-03 12:58:42 +03:00

39 lines
780 B
C

/** @file
Math worker functions.
Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include "BaseLibInternals.h"
/**
Returns the value of the highest bit set in a 64-bit value. Equivalent to
1 << log2(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
)
{
if (Operand == 0) {
return 0;
}
return LShiftU64 (1, (UINTN) HighBitSet64 (Operand));
}