From: Jan Hubicka <hubicka@ucw.cz>
Date: Tue, 23 Jan 2018 09:55:37 +0000 (+0100)
Subject: predict.c (probably_never_executed): Only use precise profile info.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=9f4b0885e77f836169c290e93faa87b58ab34276;p=gcc.git

predict.c (probably_never_executed): Only use precise profile info.

	* predict.c (probably_never_executed): Only use precise profile info.
	(compute_function_frequency): Skip after inlining hack since we now
	have quality checking.

From-SVN: r256975
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 4a29b02e488..747c3b48ab9 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2018-01-23  Jan Hubicka  <hubicka@ucw.cz>
+
+	* predict.c (probably_never_executed): Only use precise profile info.
+	(compute_function_frequency): Skip after inlining hack since we now
+	have quality checking.
+
 2018-01-23  Jan Hubicka  <hubicka@ucw.cz>
 
 	* profile-count.h (profile_probability::very_unlikely,
diff --git a/gcc/predict.c b/gcc/predict.c
index 340c7667434..724ba458db9 100644
--- a/gcc/predict.c
+++ b/gcc/predict.c
@@ -212,7 +212,12 @@ probably_never_executed (struct function *fun,
   gcc_checking_assert (fun);
   if (count == profile_count::zero ())
     return true;
-  if (count.initialized_p () && profile_status_for_fn (fun) == PROFILE_READ)
+  /* Do not trust adjusted counts.  This will make us to drop int cold section
+     code with low execution count as a result of inlining. These low counts
+     are not safe even with read profile and may lead us to dropping
+     code which actually gets executed into cold section of binary that is not
+     desirable.  */
+  if (count.precise_p () && profile_status_for_fn (fun) == PROFILE_READ)
     {
       int unlikely_count_fraction = PARAM_VALUE (UNLIKELY_BB_COUNT_FRACTION);
       if (count.apply_scale (unlikely_count_fraction, 1) >= profile_info->runs)
@@ -3759,15 +3764,10 @@ compute_function_frequency (void)
       return;
     }
 
-  /* Only first time try to drop function into unlikely executed.
-     After inlining the roundoff errors may confuse us.
-     Ipa-profile pass will drop functions only called from unlikely
-     functions to unlikely and that is most of what we care about.  */
-  if (!cfun->after_inlining)
-    {
-      node->frequency = NODE_FREQUENCY_UNLIKELY_EXECUTED;
-      warn_function_cold (current_function_decl);
-    }
+  node->frequency = NODE_FREQUENCY_UNLIKELY_EXECUTED;
+  warn_function_cold (current_function_decl);
+  if (ENTRY_BLOCK_PTR_FOR_FN (cfun)->count.ipa() == profile_count::zero ())
+    return;
   FOR_EACH_BB_FN (bb, cfun)
     {
       if (maybe_hot_bb_p (cfun, bb))