[PATCH] D30309: CodeGen: BlockPlacement: Precompute layout for chains of triangles.

[David Li via Phabricator via llvm-commits]

davidxl added a comment.

if BP is not correct,  it is better to improve static branch prediction.  We explicitly added a threshold for the cost based analysis result to kick in just to be conservative when the branch probability is not biased enough.    Even for the long chain case, tail dup is enabled for 50/50 case, but the real profile is 40/60, taildup will hurt performance. I don't see the reason to by pass the branch prob + cost analysis by just looking at the shape.


Repository:
  rL LLVM

https://reviews.llvm.org/D30309