[PATCH] D45377: [SampleFDO] Don't let inliner treat warm callsite with inline instance in the profile as cold
Wei Mi via Phabricator via llvm-commits
llvm-commits at lists.llvm.org
Wed Apr 18 08:45:31 PDT 2018
wmi added a comment.
Herald added a subscriber: chrib.
> The problem of letting regular inliner to handle warm callsites is that the callee may have profile missing if it is fully inlined. Maybe instead of comparing total_count/num_calle_bb to hot
> threshold, just compare total_count to hot threshold? I agree this may increase code size a little, but it should not be worst than the previous afdo binary?
>> Yes, that is the same concern I have in my reply to David's suggestion, but the result seems fine. I can measure your suggested way and see how it looks like.
I tested the solution of comparing total_count to hot threshold, for the two server benchmarks the performance had no change. But for the regressed benchmark, it is a little worse than the solution of comparing total_count/num_callee_bb to hot threshold -- in my three runs there were two runs for which the regression was larger than the fluctuation range the target benchmarks allows. I know it is possible there is other side-effect taking place here, but for now I don't have detail perf profile for me to find out.
Repository:
rL LLVM
https://reviews.llvm.org/D45377
More information about the llvm-commits
mailing list