+///\r
+/// Pointer to the start of a variable argument list stored in a memory buffer. Same as UINT8 *.\r
+///\r
+typedef UINTN *BASE_LIST;\r
+\r
+/**\r
+ Returns an argument of a specified type from a variable argument list and updates \r
+ the pointer to the variable argument list to point to the next argument. \r
+\r
+ This function returns an argument of the type specified by TYPE from the beginning \r
+ of the variable argument list specified by Marker. Marker is then updated to point \r
+ to the next argument in the variable argument list. The method for computing the \r
+ pointer to the next argument in the argument list is CPU specific following the EFIAPI ABI.\r
+\r
+ @param Marker Pointer to the beginning of a variable argument list.\r
+ @param TYPE The type of argument to retrieve from the beginning \r
+ of the variable argument list.\r
+ \r
+ @return An argument of the type specified by TYPE.\r
+\r
+**/\r
+#define BASE_ARG(Marker, TYPE) (*(TYPE *)((UINT8 *)(Marker = (BASE_LIST)((UINT8 *)Marker + _INT_SIZE_OF (TYPE))) - _INT_SIZE_OF (TYPE)))\r
+\r