[PATCH]: Guard division by zero in ipa-icf dumps

[Uros Bizjak]

Hello!

2014-10-24  Martin Liska  <mli...@suse.cz>

    * ipa-icf.c (sem_item_optimizer::parse_nonsingleton_classes): Guard
    division by zero in dumps.
    (sem_item_optimizer::merge_classes): Ditto.

Tested on alphaev68-linux-gnu, committed to mainline as obvious.

Uros.

diff --git a/gcc/ipa-icf.c b/gcc/ipa-icf.c
index d1238a4..e7a293e 100644
--- a/gcc/ipa-icf.c
+++ b/gcc/ipa-icf.c
@@ -1736,7 +1736,7 @@ sem_item_optimizer::parse_nonsingleton_classes (void)
 
   if (dump_file)
     fprintf (dump_file, "Init called for %u items (%.2f%%).\n", 
init_called_count,
-            100.0f * init_called_count / m_items.length ());
+            m_items.length () ? 100.0f * init_called_count / m_items.length 
(): 0.0f);
 }
 
 /* Equality function for semantic items is used to subdivide existing
@@ -2196,14 +2196,15 @@ sem_item_optimizer::merge_classes (unsigned int 
prev_class_count)
       fprintf (dump_file, "Congruent classes before: %u, after: %u\n",
               prev_class_count, class_count);
       fprintf (dump_file, "Average class size before: %.2f, after: %.2f\n",
-              1.0f * item_count / prev_class_count,
-              1.0f * item_count / class_count);
+              prev_class_count ? 1.0f * item_count / prev_class_count : 0.0f,
+              class_count ? 1.0f * item_count / class_count : 0.0f);
       fprintf (dump_file, "Average non-singular class size: %.2f, count: %u\n",
-              1.0f * non_singular_classes_sum / non_singular_classes_count,
+              non_singular_classes_count ? 1.0f * non_singular_classes_sum /
+              non_singular_classes_count : 0.0f,
               non_singular_classes_count);
       fprintf (dump_file, "Equal symbols: %u\n", equal_items);
       fprintf (dump_file, "Fraction of visited symbols: %.2f%%\n\n",
-              100.0f * equal_items / item_count);
+              item_count ? 100.0f * equal_items / item_count : 0.0f);
     }
 
   for (hash_table<congruence_class_group_hash>::iterator it = m_classes.begin 
();