Avoid updating hot bb threshold in call speculation code

This patch removes apparently forgotten debugging hack (which got in during
the speculative call patchset) which reduces hot bb threshold.  This does not
make sense since it is set and reset randomly as the summaries are processed.
One problem is that we set the BB threshold to make certain BBs hot and hten
unrolling or vectorization may reduce it to some fraction of the count that
makes it cold.  We may want to add some buffer and divide the value by,
say 32, but that shoulid be done independently of speculative calls.

gcc/ChangeLog:

2021-12-11  Jan Hubicka  <hubicka@ucw.cz>

	* ipa-profile.c (ipa_profile): Do not update hot bb threshold.

diff --git a/gcc/ipa-profile.c b/gcc/ipa-profile.c
index ce32b538976d2a12a83d41691bbfe0a18918c6e9..02f42d9b0f74ecf44cff1fdf900fa594a3b91ad1 100644 (file)
--- a/gcc/ipa-profile.c
+++ b/gcc/ipa-profile.c
@@ -854,18 +854,6 @@ ipa_profile (void)
              node_map_initialized = true;
              ncommon++;
 
-             if (in_lto_p)
-               {
-                 if (dump_file)
-                   {
-                     fprintf (dump_file,
-                              "Updating hotness threshold in LTO mode.\n");
-                     fprintf (dump_file, "Updated min count: %" PRId64 "\n",
-                              (int64_t) threshold / spec_count);
-                   }
-                 set_hot_bb_threshold (threshold / spec_count);
-               }
-
              unsigned speculative_id = 0;
              profile_count orig = e->count;
              for (unsigned i = 0; i < spec_count; i++)