Microprocessor having branch prediction function

Details Microprocessor having branch prediction function Microprocessor having branch prediction function

1991-05-22

1994-07-05

Bowler, Alyssa H.

Boots, shoes, and leggings

395800, 364DIG1, 3642613, 3642631, 3642617, G06F 926

Patent

active

053275365

ABSTRACT:
A microprocessor which prefetches instructions in words which contain a fixed plurality of bytes based on addresses which disregard one or more less significant bits and in which instructions comprises a variable number of bytes includes an adder for supplying information regarding the starting location for each instruction within a multi-byte, prefetched word held in a queue for alignment of the instruction for decoding by an instruction decoder. Upon the occurrence of an unconditional branch instruction or a conditional branch instruction in which the condition is met, a multiplexer is used to substitute a starting location stored in a branch hit table for the branch target instruction within a multi-byte, prefetched word for the starting for the starting location developed by the adder. Prefetching is performed by incrementing addresses by a number corresponding to the number of less significant bits disregarded in the addresses and accessing a branch prediction table and also the branch hit table when a branching instruction is encountered. An acknowledgement of a prefetch is then used to serialize prefetching of the word containing the start location of the branch target. If the branch target is also a branch instruction, this serialization allows repetition of the prefetch through a number of branching instructions limited only by the capacity of the branch hit table and disturbance of pipelined processing is thereby reduced.

REFERENCES:
patent: 4725947 (1988-02-01), Shonai et al.
patent: 4894772 (1990-01-01), Langendorf
patent: 4943908 (1990-07-01), Emma et al.
patent: 4984154 (1991-01-01), Hanatani et al.
patent: 5093778 (1992-03-01), Favor et al.
patent: 5185869 (1993-02-01), Suzuki et al.

Affiliated with

Also associated with

Rating

Microprocessor having branch prediction function does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Microprocessor having branch prediction function, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Microprocessor having branch prediction function will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-803167