The following applies a micro-optimization to find_hard_regno_for_1, re-ordering the check so we can easily jump-thread by using an else. This reduces the time spent in this function by 15% for the testcase in the PR.
Bootstrap & regtest running on x86_64-unknown-linux-gnu, OK if that passes? Thanks, Richard. PR rtl-optimization/110587 * lra-assigns.cc (find_hard_regno_for_1): Re-order checks. --- gcc/lra-assigns.cc | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/gcc/lra-assigns.cc b/gcc/lra-assigns.cc index b8582dcafff..d2ebcfd5056 100644 --- a/gcc/lra-assigns.cc +++ b/gcc/lra-assigns.cc @@ -522,14 +522,15 @@ find_hard_regno_for_1 (int regno, int *cost, int try_only_hard_regno, r2 != NULL; r2 = r2->start_next) { - if (r2->regno >= lra_constraint_new_regno_start + if (live_pseudos_reg_renumber[r2->regno] < 0 + && r2->regno >= lra_constraint_new_regno_start && lra_reg_info[r2->regno].preferred_hard_regno1 >= 0 - && live_pseudos_reg_renumber[r2->regno] < 0 && rclass_intersect_p[regno_allocno_class_array[r2->regno]]) sparseset_set_bit (conflict_reload_and_inheritance_pseudos, r2->regno); - if (live_pseudos_reg_renumber[r2->regno] >= 0 - && rclass_intersect_p[regno_allocno_class_array[r2->regno]]) + else if (live_pseudos_reg_renumber[r2->regno] >= 0 + && rclass_intersect_p + [regno_allocno_class_array[r2->regno]]) sparseset_set_bit (live_range_hard_reg_pseudos, r2->regno); } } -- 2.35.3