Branch prediction

Colin Percival colin.percival at wadham.ox.ac.uk
Mon Feb 16 05:51:31 PST 2004


At 16:42 15/02/2004, Trent Nelson wrote:
>does the old adage of "always predict
>false" still hold true the first time a branch is encountered?

   Most processors predict that forward branches are not taken,
and backward branches are taken (since backward branches occur
most often in loops).
   Of course, some processors now have hints (conditional-jump-
which-is-usually-taken, conditional-jump-which-is-usually-not-
taken, etc.)

Colin Percival




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