[PATCH] D34220: [AArch64] Prefer B.cond to CBZ/CBNZ/TBZ/TBNZ when NZCV flags can be set for "free"

[Matthias Braun via Phabricator via llvm-commits]

MatzeB accepted this revision.
MatzeB added a comment.
This revision is now accepted and ready to land.

I'm fine with coding style and transformation.

I'm always a bit sad to see whole new passes for simple/local patterns. There is already other passes like MachineCombiner and MachinePeephole, DeadMachineInstructionElim that also just go through all instruction looking for a pattern and don't need any analysis upfront. Unfortunately none of them is extensible and they are at slightly different positions in the pipeline. I guess we do not need to solve/improve this situation with this patch. Though I reserve the right to ask for a revert and replanning if the bots measure slowdowns in CTMark after committing this.

So LGTM.


https://reviews.llvm.org/D34220