On Tue, Oct 15, 2013 at 2:03 PM, Jan Hubicka <hubi...@ucw.cz> wrote: >> Yes, that would work. So let's discard this patch because the fix for >> comdat can also fix this problem. > > Unforutnately ipa-profile-estimate is an IPA pass and as such it does > not have access to profile_status_to_function.
I see. I was coding that up today but hadn't tested it yet. > You can probably just factor this out into a function that can be called > and for normal FDO we call it where the loop stis now and for auto-FDO we can > probably have another invocation from before early passes where auto-FDO is > collected. Ok, let's go with that approach for now. It won't address the 0 count COMDAT calling another 0 count COMDAT problem, but I will probably just find a way to deal with this when inlining. >> >>> + if (node->count) >> >>> + continue; > Also here we should sum the counts and consider function non unlikely executed > in the same way as probably_never_executed does. I assume you mean by doing the same comparison to the number of profile->runs. Yes, this makes sense. > > I can prepare updated patch, but i am currently travelling, so i would not > be disapointed if you beat me ;) I'm working on it, and I think based on Dehao's needs I am going to split up the patch into two phases, the one that does just the part you had sent a patch for (making sure 0 count routines with non-zero calls are marked guessed and have their node frequency set appropriately), and a subsequent one to do the count application when we inline a 0-count routine into a non-zero callsite. I'll shoot for getting this ready by tomorrow. BTW, in your original patch you are checking for both e->count or cgraph_maybe_hot_edge_p(e), but AFAICT the call to cgraph_maybe_hot_edge_p will never return true when e->count is zero. When there is a profile it will return false via maybe_hot_count_p since e->count == 0. When there is no profile it will return false when the callee has NODE_FREQUENCY_UNLIKELY_EXECUTED. So I think just checking for e->count >0 is sufficient here. Thanks, Teresa > > Honza -- Teresa Johnson | Software Engineer | tejohn...@google.com | 408-460-2413
