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Table 4.7 Branch management techniques.
ApproachWhat It DoesCostEffect on Branch Delay (Taken Branch)Effect on Branch Prediction
Speedup
Early CC setDetermine outcome of tested condition earlyNilCan save up to a cycleNone
Delayed branch"Small"None
Branch adderDetermine target address earlySmallGenerally saves a cycleNone
Prediction
Static:Use branch opcode or test to predict outcomeSmallNone6070% accurate
Dynamic:
HistoryRecords outcome of each branchSome increase in I-cache sizeNone7090+% accurate
Branch table bufferStores last target inst for each branch in a special associative tableCan be significant for large tablesCan reduce to zero7090+% accuracy; depends on size and application

 
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