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diff --git a/UnixPkg/Library/UnixBaseLib/HighBitSet32.c b/UnixPkg/Library/UnixBaseLib/HighBitSet32.c
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+/** @file
+ Math worker functions.
+
+ Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
+ 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 bit position of the highest bit set in a 32-bit value. Equivalent
+ to log2(x).
+
+ This function computes the bit position of the highest bit set in the 32-bit
+ value specified by Operand. If Operand is zero, then -1 is returned.
+ Otherwise, a value between 0 and 31 is returned.
+
+ @param Operand The 32-bit operand to evaluate.
+
+ @retval 0..31 Position of the highest bit set in Operand if found.
+ @retval -1 Operand is zero.
+
+**/
+INTN
+EFIAPI
+HighBitSet32 (
+ IN UINT32 Operand
+ )
+{
+ INTN BitIndex;
+
+ if (Operand == 0) {
+ return - 1;
+ }
+ for (BitIndex = 31; (INT32)Operand > 0; BitIndex--, Operand <<= 1);
+ return BitIndex;
+}