FAULT TOLERANT DATA PROCESSING SYSTEM AND METHOD THEREFOR

摘要

A fault tolerant data processing system includes means for maintaining copies of original index registers and copies of modified index registers such that in the event original copies of the index registers are needed, they may be restored. Thus, in the event of a rollback, original copies of the index registers may be restored to a processor (36), even if some of the index registers were modified in the previous execution of a command by the processor (36).