Siirete (hargnemiste) ennustamine.(Branch Prediction)
Pipelined machines must fetch the next instruction before they have completely
executed the previous instruction. If the previous instruction was a branch, then the
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next-instruction fetch could have been to the wrong place. Branch prediction is a
technique that attempts to infer the proper next instruction address, knowing only the
current one. Typically it uses a Branch Target Buffer (BTB), a small, associative
memory that watches the instruction cache index and tries to predict which index
should be accessed next, based on branch history. Optimizing the actual algorithm
used in retaining the history of each entry is an area.