[PATCH] D33577: CodeGen: BlockPlacement: Use Branching factor to choose between near equals.

[David Li via Phabricator via llvm-commits]

davidxl added a comment.

It is basically a choice between a layout (exiting) that has 50% chance of not taking any branches , 25% of taking one branch, and 25% of taking more than one branches   vs the new layout that has only 6.25% chance of taking zero branch and 93.75% of taking only one branch.

The existing layout only has 25% chance of taking more than 2 branches -- is it worth sacrificing  43.75% of chances to not take any branches for the improvement for the 25% cases?


Repository:
  rL LLVM

https://reviews.llvm.org/D33577