MdePkg: Replace BSD License with BSD+Patent License

[mirror_edk2.git] / MdePkg / Library / BaseLib / HighBitSet32.c

/** @file\r
  Math worker functions.\r
\r
  Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
\r
\r
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#include "BaseLibInternals.h"\r
\r
/**\r
  Returns the bit position of the highest bit set in a 32-bit value. Equivalent\r
  to log2(x).\r
\r
  This function computes the bit position of the highest bit set in the 32-bit\r
  value specified by Operand. If Operand is zero, then -1 is returned.\r
  Otherwise, a value between 0 and 31 is returned.\r
\r
  @param  Operand The 32-bit operand to evaluate.\r
\r
  @retval 0..31  Position of the highest bit set in Operand if found.\r
  @retval -1     Operand is zero.\r
\r
**/\r
INTN\r
EFIAPI\r
HighBitSet32 (\r
  IN      UINT32                    Operand\r
  )\r
{\r
  INTN                              BitIndex;\r
\r
  if (Operand == 0) {\r
    return - 1;\r
  }\r
  for (BitIndex = 31; (INT32)Operand > 0; BitIndex--, Operand <<= 1);\r
  return BitIndex;\r
}\r