[PATCH] D22317: Codegen: Tail Merge: Be less aggressive with special cases.

[David Li via llvm-commits]

davidxl added a comment.

There are two independent issues here

1. one issue is the interaction of tailDup and tailMerge.  The right fix is to make the post-layout tailMerge really restrictive (such that it does not undo post-layout tailDup decisions).   Your current patch with added check !AfterPlacement as I suggested can probably accomplish that

2. the bug you mentioned that merges loop top and bottom tests.

We shall probably proceed with 1) and make tailDup enhancement your have in.   The right way to approach 2) can be handled later. WDT?


Repository:
  rL LLVM

https://reviews.llvm.org/D22317