https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114412
--- Comment #5 from Tamar Christina <tnfchris at gcc dot gnu.org> --- (In reply to Filip Kastl from comment #4) > (In reply to Tamar Christina from comment #3) > > Hi Filip, > > > > Do you generate these runs with counters based PGO or compiler > > instrumentation? > > > > Just so I know before I start trying to reproduce them. > > Hi Tamar, > > By counters you mean some sort of hardware counters? I didn't know there > were multiple ways to do PGO with GCC. > > I think that the answer to your question is "compiler instrumentation". I > just do -fprofile-generate, run the instrumented binary and then > -fprofile-use. Yeah, with some elbow grease the perf record method works too, but it's not very accurate on Armv8. I'll try to reproduce and bisect these over the weekend!
