Advanced Computer Architecture, Imperial College 2001
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Correlating branch prediction - Summary
•Saturating counter (bimodal) scheme handles highly-biased branches well
•Some applications have highly dynamic branches
•The idea of correlating prediction is to use recent branch history to predict future
•Issues:
–How much branch history (BHR size)
–How to minimise interference in the BHT
–How to weight local history vs global history
–Combining different policies dynamically (selective scheme) is expensive - but effective