摘要 |
<p>A branch prediction mechanism comprises: a prediction memory (40); a hash device (44) connected to receive instruction addressed from an instruction address register (42); an address register (46) connected with the prediction memory for receiving hash addresses from the hash device; an address buffer (48) for receiving hash addresses from the hash address device; a count register (54) for receiving the output from the prediction memory; a count buffer (58) for receiving output counts from the count register: an increment-decrement unit (56) for receiving input counts from said count buffer and branch outcome inormation for updating the count according to the branch outcome; and a write data register (52) for receiving the updated count information from the increment-decrement unit, the branch prediction mechanism, in operation, operating to predict branch instructions on a continuously updated history of recently executed branch instructions. </p> |