On Thu, Mar 7, 2019 at 10:50 AM Martin Liška <mli...@suse.cz> wrote: > > On 3/7/19 9:54 AM, Uros Bizjak wrote: > > On Thu, Mar 7, 2019 at 9:45 AM Martin Liška <mli...@suse.cz> wrote: > >> > >> Hi. > >> > >> Thanks to Intel guys, we've done some re-measurement in PR86952 > >> about usage of jump tables when retpolines are used. > >> Numbers prove that disabling of JT should be the best for now. > >> > >> Patch can bootstrap on x86_64-linux-gnu and survives regression tests. > >> > >> Ready to be installed? > >> Thanks, > >> Martin > > > > Please add a comment above your change. > > Sure, should be improved.
Eh, we didn't understand each other... Please add comment here: + if (ix86_indirect_branch != indirect_branch_keep + && !opts_set->x_flag_jump_tables) + opts->x_flag_jump_tables = 0; so in future, it will still be documented why this part of the code is needed. Uros. > Martin > > > > > Uros. > > > >> > >> gcc/ChangeLog: > >> > >> 2019-03-06 Martin Liska <mli...@suse.cz> > >> > >> PR target/86952 > >> * config/i386/i386.c (ix86_option_override_internal): Disable > >> jump tables when retpolines are used. > >> > >> gcc/testsuite/ChangeLog: > >> > >> 2019-03-06 Martin Liska <mli...@suse.cz> > >> > >> PR target/86952 > >> * gcc.target/i386/pr86952.c: New test. > >> * gcc.target/i386/indirect-thunk-7.c: Use jump tables to match > >> scanned pattern. > >> * gcc.target/i386/indirect-thunk-inline-7.c: Likewise. > >> --- > >> gcc/config/i386/i386.c | 4 ++++ > >> .../gcc.target/i386/indirect-thunk-7.c | 2 +- > >> .../gcc.target/i386/indirect-thunk-inline-7.c | 2 +- > >> gcc/testsuite/gcc.target/i386/pr86952.c | 23 +++++++++++++++++++ > >> 4 files changed, 29 insertions(+), 2 deletions(-) > >> create mode 100644 gcc/testsuite/gcc.target/i386/pr86952.c > >> > >> >
