https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114787
--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
It is the
if (dump_file && (dump_flags & TDF_DETAILS)
&& max_loop_iterations_int (loop) >= 0)
{
fprintf (dump_file,
"Loop %d iterates at most %i times.\n", loop->num,
(int)max_loop_iterations_int (loop));
}
if (dump_file && (dump_flags & TDF_DETAILS)
&& likely_max_loop_iterations_int (loop) >= 0)
{
fprintf (dump_file, "Loop %d likely iterates at most %i times.\n",
loop->num, (int)likely_max_loop_iterations_int (loop));
}
cases which trigger the different code generation with
-fdump-tree-profile_estimate-details -O1, either of them; guess
max_loop_iterations_int and likely_max_loop_iterations_int cache the results
and while it doesn't change the IL from the profile_estimate pass, it changes
the behavior of the cunroll pass later on.
