[llvm] [BranchFolding] Fold fallthroughs into conditional tailcalls if profitable (PR #140476)

[Nabeel Omer via llvm-commits]

omern1 wrote:

Hi @RKSimon, this slipped through the cracks.

Apologies for the force push, I accidentally rebased instead of merging.

Pinging @llvm/pr-subscribers-pgo for reviews.

https://github.com/llvm/llvm-project/pull/140476