[PATCH] D36504: [CodeGenPrepare][WIP] Convert uncond. branch to return into a return to help with shrink-wrapping

[Krzysztof Parzyszek via Phabricator via llvm-commits]

kparzysz added a comment.

In https://reviews.llvm.org/D36504#913010, @sfertile wrote:

> So I attempted this in the PreRA tail-duplication pass. Unfortunately by the time we get there the opportunity is gone.  If we do not duplicate the return then CodegenPrepare will end up deleting  the `for.cond.cleanup.loopexit` block and we loose the shrink wrapping opportunity.


Then perhaps shrink-wrapping should be extended to be able to add blocks.  CodeGenPrepare is not the place for this.


Repository:
  rL LLVM

https://reviews.llvm.org/D36504