Add AccessMsrDb.s for MSFT tool chain. It uses raw data to represent instructions...

[mirror_edk2.git] / MdePkg / Library / BaseLib / GetPowerOfTwo64.c

diff --git a/MdePkg/Library/BaseLib/GetPowerOfTwo64.c b/MdePkg/Library/BaseLib/GetPowerOfTwo64.c
index 9994fb8f12e29acd8cc6cf2bfbebc13deb1d5735..344ce27519e0c70522f8a64896016dc043ba4d86 100644 (file)
--- a/MdePkg/Library/BaseLib/GetPowerOfTwo64.c
+++ b/MdePkg/Library/BaseLib/GetPowerOfTwo64.c
@@ -12,11 +12,14 @@
 \r
 **/\r
 \r
+\r
+\r
+\r
 #include "BaseLibInternals.h"\r
 \r
 /**\r
   Returns the value of the highest bit set in a 64-bit value. Equivalent to\r
-  1 << HighBitSet64(x).\r
+  1 << log2(x).\r
 \r
   This function computes the value of the highest bit set in the 64-bit value\r
   specified by Operand. If Operand is zero, then zero is returned.\r
@@ -33,7 +36,9 @@ GetPowerOfTwo64 (
   IN      UINT64                    Operand\r
   )\r
 {\r
-  INTN                              BitPos;\r
+  if (Operand == 0) {\r
+    return 0;\r
+  }\r
 \r
-  return (BitPos = HighBitSet64 (Operand)) > 0 ? LShiftU64 (1, BitPos) : 0;\r
+  return LShiftU64 (1, HighBitSet64 (Operand));\r
 }\r