Nah it didn't have an extra chip -- but large portions of the game were written in microcode for the N64's processor specifically. It's part of what makes it and Rogue Squadron kind of a pain to emulate -- along with using their own audio drivers (MoSYS/MusyX that were later used as the basis for the GameCube sound systems).
IIRC there was an official Windows port at some point though. Not sure how well it worked or works on modern systems.