Hi, > Ping? Sorry for the delay. I think I finally got auto-fdo running on my box and indeed I see that if function is cloned later, the profile is lost. There are .suffixes added before afdo pass (such as openmp offloading or nested functions) and there are .suffixes added afer afdo (by ipa cloning and LTO privatization). I see we want to merge those created by ipa cloning (after afdo pass). But I do not think we want to merge those for i.e. nested functions since those are actual different functions or for openmp offloading.
I also wonder what happens with LTO privatization - i.e. how we look up what static function does the symbol belong? Overwritting the data by the last clone is definitely bad, so the patch is OK, but we should figure out what happens in the cases above. Also if we merge, it may happen that the clone is noticeably different from original - for example with ipa split it may be missing part of the body. Merging the tables elementwise is safe then? Honza > > Thanks, > Kugan > > > > > On 9 May 2025, at 11:54 am, Kugan Vivekanandarajah > > <kvivekana...@nvidia.com> wrote: > > > > External email: Use caution opening links or attachments > > > > > > This patch add support for merging profiles from multiple clones. > > That is, when optimized binaries have clones such as IPA-CP clone or SRA > > clones, genarted gcov will have profiled them spereately. > > Currently we pick one and ignore the rest. This patch fixes this by > > merging the profiles. > > > > > > Regression tested on aarch64-linux-gnu with no new regression. > > Also successfully done autoprofiledbootstrap with the relevant patch. > > > > Is this OK for trunk? > > Thanks, > > Kugan > > >
