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-rw-r--r--MdePkg/Library/BaseLib/LowBitSet32.c49
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diff --git a/MdePkg/Library/BaseLib/LowBitSet32.c b/MdePkg/Library/BaseLib/LowBitSet32.c
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+/** @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 common header file for this module.
+//
+#include "CommonHeader.h"
+
+#include "BaseLibInternals.h"
+
+/**
+ Returns the bit position of the lowest bit set in a 32-bit value.
+
+ This function computes the bit position of the lowest 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.
+
+ @return Position of the lowest bit set in Operand if found.
+ @retval -1 Operand is zero.
+
+**/
+INTN
+EFIAPI
+LowBitSet32 (
+ IN UINT32 Operand
+ )
+{
+ INTN BitIndex;
+
+ if (Operand == 0) {
+ return -1;
+ }
+
+ for (BitIndex = 0; (Operand & 1) == 0; BitIndex++, Operand >>= 1);
+ return BitIndex;
+}