There was never an included auto-calculation of CR or XP in the PFRPG ruleset (or 3.5E), it was up to the GM to fill it out themselves. Probably because in 3.5E the CR/XP calculation can get complex based of the party levels etc. and so it was left to the GM to fill out as required.
There was an extension created by RTFallen that auto calculated XP/CR for an encounter, but that is no longer maintained and not fully compatible.

