2 ms·

Conditional moves tend to work even better on small in-order designs than later OoOE cores.

• kramerger 3y ago
  My assumption is that larger designs means longer pipelines and that increases the penalty of missed conditional jumps. On a 3 or 5-stage pipeline things are not as bad.
  • monocasa 3y ago
    Sort of. The bigger issue is that in larger OoOE cores, the predicate ends up being a speculation barrier if you don't predict it. So you need hardware similar to a branch predictor guessing those predicates. At that point it's easier to just point people towards conditional jumps where you ostensibly have very good branch prediction if you have any sort of predictability and spend your gate budget there where it's more likely to be more generally used.