MdePkg/Library/BaseLib/GetPowerOfTwo32.c

   1 /** @file
   2   Math worker functions.
   3
   4   Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
   5   SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7 **/
   8
   9 #include "BaseLibInternals.h"
  10
  11 /**
  12   Returns the value of the highest bit set in a 32-bit value. Equivalent to
  13   1 << log2(x).
  14
  15   This function computes the value of the highest bit set in the 32-bit value
  16   specified by Operand. If Operand is zero, then zero is returned.
  17
  18   @param  Operand The 32-bit operand to evaluate.
  19
  20   @return 1 << HighBitSet32(Operand)
  21   @retval 0 Operand is zero.
  22
  23 **/
  24 UINT32
  25 EFIAPI
  26 GetPowerOfTwo32 (
  27   IN      UINT32  Operand
  28   )
  29 {
  30   if (0 == Operand) {
  31     return 0;
  32   }
  33
  34   return 1ul << HighBitSet32 (Operand);
  35 }