A mechanism for exception and interrupt handling in multithreaded
multiprocessors is provided. The mechanism allows the handling of
exceptions and interruptions in a multithreaded multiprocessor computer,
while hiding the multiprocessor nature of the computer from the operating
system. Generally, when an operating system is cognizant of the
multiprocessor nature of a computer, additional overhead may be required
when handling exceptions and interruptions. Due to the overhead involved
in saving and restoring processing states, the performance of a processor
may be significantly impacted. Additional circuitry is provided which
allows the multiprocessor nature of the computer to be hidden from the
operating system, while minimizing the overhead necessary for proper
handling.