From 5b06b3b8771d0dc06426986be32b8599e97bb451 Mon Sep 17 00:00:00 2001 From: Jan Hubicka Date: Thu, 27 Jul 2023 15:58:52 +0200 Subject: [PATCH] Fix profile update in tree-ssa-loop-im.cc This fixes two bugs in tree-ssa-loop-im.cc. First is that cap probability is not reliable, but it is constructed with adjusted quality. Second is that sometimes the conditional has wrong joiner BB count. This is visible on testsuite/gcc.dg/pr102385.c however the testcase triggers another profile update bug in pcom, so I will update it in followup patch. gcc/ChangeLog: * tree-ssa-loop-im.cc (execute_sm_if_changed): Turn cap probability to guessed; fix count of new_bb. --- gcc/tree-ssa-loop-im.cc | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/gcc/tree-ssa-loop-im.cc b/gcc/tree-ssa-loop-im.cc index f5b01e986ae..268f466bdc9 100644 --- a/gcc/tree-ssa-loop-im.cc +++ b/gcc/tree-ssa-loop-im.cc @@ -2059,7 +2059,8 @@ execute_sm_if_changed (edge ex, tree mem, tree tmp_var, tree flag, nbbs++; } - profile_probability cap = profile_probability::always ().apply_scale (2, 3); + profile_probability cap + = profile_probability::guessed_always ().apply_scale (2, 3); if (flag_probability.initialized_p ()) ; @@ -2103,6 +2104,8 @@ execute_sm_if_changed (edge ex, tree mem, tree tmp_var, tree flag, old_dest = ex->dest; new_bb = split_edge (ex); + if (append_cond_position) + new_bb->count += last_cond_fallthru->count (); then_bb = create_empty_bb (new_bb); then_bb->count = new_bb->count.apply_probability (flag_probability); if (irr)