Hi Honza, > On 26 May 2025, at 5:28 pm, Jan Hubicka <hubi...@ucw.cz> wrote: > > External email: Use caution opening links or attachments > > > 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.
IMO get_original_name should handle this. We want to strip the suffix only for the functions that are cloned afterwards. Stripping suffixes for all the functions is not correct. We need to know the suffixes that are created later and stip only them Clone names we should strip: * SRA clones (of the form foo.isra.0) * IPA-CP clonse (in the form bar.constprop.123) * Partial inlining clones (foo.part.0, foo.cold) Others that should not be stripped: * target_clones (foo.arch_x86_64_v2, foo.avx2) * OpenMP related suffixes (.omp_fn.N, .omp_cpyfn.N) Is that what you want? > > I also wonder what happens with LTO privatization - i.e. how we look up > what static function does the symbol belong? This as Dhruv mentioned need change to gcov itself. Private (static) functions with the same name also will have the same issue. Dhruv is working on an RFC for this. Thanks, Kugan > > 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 >>> >> > > >
