+#elif defined (COMPILER_MSVC)
+ unsigned long index;
+#ifdef WIN64
+ if (0 != _BitScanForward64(&index, (__int64)x))
+#else
+ if (0 != _BitScanForward(&index, (unsigned long)x))
+#endif
+ index++; // Make the result 1-based
+ else
+ index = 0; // All bits were zero
+
+ return (int)index;