XSB extends Prolog with tabled resolution and HiLog (a standard extension of Prolog permitting limited higher-order logic programming).[1]Tabled resolution is a very useful feature in logic programming. SWI-Prolog has its own implementation which seems to be less mature than XSB's[2]. SWI-Prolog's documentation of the feature states its two uses: memoization[3] and avoiding non-termination. Check http://www.swi-prolog.org/pldoc/man?section=tabling for more details.
All of the following operations are performed on a 64-bit Linux Debian "jessie" 8.0 machine.
