https://gcc.gnu.org/bugzilla/show_bug.cgi?id=28614
Tobias Burnus <burnus at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |burnus at gcc dot gnu.org
--- Comment #10 from Tobias Burnus <burnus at gcc dot gnu.org> ---
AMD GCN result (cc1 -O1) sampled with 'perf', aborting after 10½min:
Samples: 2M of event 'cpu_core/cycles/Pu', Event count (approx.):
2374461441070, Thread: cc1, DSO: cc1
Overhead Com Symbol
26,65% cc1 [.] assign_by_spills()
22,36% cc1 [.] bitmap_set_bit(bitmap_head*, int)
20,02% cc1 [.] update_lives(int, bool)
17,91% cc1 [.] bitmap_clear_bit(bitmap_head*, int)
5,73% cc1 [.] insert_in_live_range_start_chain(int)
1,83% cc1 [.] find_hard_regno_for_1(int, int*, int, bool, HARD_REG_SET)
0,84% cc1 [.] process_bb_lives(basic_block_def*, int&, bool)
0,75% cc1 [.] lra_spill()
the assign_by_spills is dominated by
if (hard_regno < 0 && reload_p)
hard_regno = spill_for (regno, &all_spilled_pseudos, iter == 1);
namely in spill_for, the
for (r = lra_reg_info[spill_regno].live_ranges;
r != NULL;
r = r->next)
{
...
if (r2->regno >= lra_constraint_new_regno_start)
sparseset_set_bit (live_range_reload_inheritance_pseudos,
r2->regno);
dominates.
