>> Cost model used by self-recursive cloning is mainly based on existing stuffs >> in ipa-cp cloning, size growth and time benefit are considered. But since >> recursive cloning is a more aggressive cloning, we will actually have another >> problem, which is opposite to your concern. By default, current parameter >> set used to control ipa-cp and recursive-inliner gives priority to code size, >> not completely for performance. This makes ipa-cp behave somewhat
> Yes, for a while the cost model is quite off. On Firefox it does just > few clonings where code size increases so it desprately needs retuning. > But since rescursive cloning is quite a different case from normal one, > perhaps having independent set of limits would help in particular ... I did consider this way, but this seems to be contradictory for normal and recursive cloning. > > Do you have some data on code size/performance effects of this change? > For spec2017, no obvious code size and performance change with default > setting. > Specifically, for exchange2, with ipa-cp-eval-threshold=1 and > ipcp-unit-growth=80, > performance +31%, size +7%, on aarch64. > ... it will help here since ipa-cp-eval-threshold value needed are quite off > of what we need to do. > I wonder about the 80% of unit growth which is also more than we can > enable by default. How it comes the overal size change is only 7%? 343624 -> 365632 (this contains debug info, -g) recursion-depth=8 273488 -> 273760 (no debug info) recursion-depth=8
