1 files changed, 44 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseLib/GetPowerOfTwo64.c b/MdePkg/Library/BaseLib/GetPowerOfTwo64.c
new file mode 100644
index 000000000000..021b30e764b9
--- /dev/null
+++ b/MdePkg/Library/BaseLib/GetPowerOfTwo64.c
@@ -0,0 +1,44 @@
+/** @file
+  Math worker functions.
+
+  Copyright (c) 2006 - 2010, 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 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));
+}