Branch lookahead prefetch for microprocessors

Electrical computers and digital processing systems: processing – Dynamic instruction dependency checking – monitoring or... – Reducing an impact of a stall or pipeline bubble

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C712S237000

Reexamination Certificate

active

07877580

ABSTRACT:
A method of handling program instructions in a microprocessor which reduces delays associated with mispredicted branch instructions, by detecting the occurrence of a stall condition during execution of the program instructions, speculatively executing one or more pending instructions which include at least one branch instruction during the stall condition, and determining the validity of data utilized by the speculative execution. Dispatch logic determines the validity of the data by marking one or more registers of an instruction dispatch unit to indicate which results of the pending instructions are invalid. The speculative execution of instructions can occur across multiple pipeline stages of the microprocessor, and the validity of the data is tracked during their execution in the multiple pipeline stages while monitoring a dependency of the speculatively executed instructions relative to one another during their execution in the multiple pipeline stages.

REFERENCES:
patent: 5471626 (1995-11-01), Carnevale et al.
patent: 5758051 (1998-05-01), Moreno et al.
patent: 5974538 (1999-10-01), Wilmot, II
patent: 5987594 (1999-11-01), Panwar et al.
patent: 6356918 (2002-03-01), Chuang et al.
patent: 6427207 (2002-07-01), Col et al.
patent: 6430683 (2002-08-01), Arimilli et al.
patent: 6473837 (2002-10-01), Hughes et al.
patent: 6950925 (2005-09-01), Sander et al.
patent: 7114060 (2006-09-01), Chaudhry et al.
patent: 7194604 (2007-03-01), Bigelow et al.
patent: 7257699 (2007-08-01), Chaudhry et al.
patent: 7376794 (2008-05-01), Steely, Jr. et al.
patent: 7421567 (2008-09-01), Eickemeyer et al.
patent: 7444498 (2008-10-01), Eickemeyer et al.
patent: 7490229 (2009-02-01), Tremblay et al.
patent: 2003/0126406 (2003-07-01), Hammarlund et al.
patent: 2005/0055541 (2005-03-01), Aamodt et al.
patent: 2005/0223200 (2005-10-01), Tremblay et al.
Balasubramonian et al., “Dynamically Allocating Processor Resources between Nearby and Distant ILP,” ACM SIGARCH Computer Architecture News pp. 26-37 (May 2001).

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Branch lookahead prefetch for microprocessors does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Branch lookahead prefetch for microprocessors, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Branch lookahead prefetch for microprocessors will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2646724

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.