On Tue, Apr 2, 2024 at 10:03 AM Jan Hubicka <hubi...@ucw.cz> wrote: > > > > I am bit worried about commonly used functions getting "infected" by > > > being called once from ifunc resolver. I think we only use thread local > > > storage for indirect call profiling, so we may just disable indirect > > > call profiling for these functions. > > > > Will change it. > > > > > Also the patch will be noop with -flto -flto-partition=max, so probably > > > we need to compute this flag at WPA time and stream to partitions. > > > > > > > Why is it a nop with -flto -flto-partition=max? I got > > > > (gdb) bt > > #0 symtab_node::check_ifunc_callee_symtab_nodes () > > at /export/gnu/import/git/gitlab/x86-gcc/gcc/symtab.cc:1440 > > #1 0x0000000000e487d3 in symbol_table::compile (this=0x7fffea006000) > > at /export/gnu/import/git/gitlab/x86-gcc/gcc/cgraphunit.cc:2320 > > #2 0x0000000000d23ecf in lto_main () > > at /export/gnu/import/git/gitlab/x86-gcc/gcc/lto/lto.cc:687 > > #3 0x00000000015254d2 in compile_file () > > at /export/gnu/import/git/gitlab/x86-gcc/gcc/toplev.cc:449 > > #4 0x00000000015284a4 in do_compile () > > at /export/gnu/import/git/gitlab/x86-gcc/gcc/toplev.cc:2154 > > #5 0x0000000001528864 in toplev::main (this=0x7fffffffd84a, argc=16, > > argv=0x42261f0) at > > /export/gnu/import/git/gitlab/x86-gcc/gcc/toplev.cc:2310 > > #6 0x00000000030a3fe2 in main (argc=16, argv=0x7fffffffd958) > > at /export/gnu/import/git/gitlab/x86-gcc/gcc/main.cc:39 > > > > Do you have a testcase to show that it is a nop? > Aha, sorry. I tought this is run during late optimization, but it is > done early, so LTo partitioning does not mix things up. So current > patch modified to disable only instrumentation that needs TLS should be > fine. >
Done. Here is the v3 patch: https://gcc.gnu.org/pipermail/gcc-patches/2024-April/648733.html -- H.J.
