Gather statistics on how many sub-ranges are used in widest_irangeranger

throughout the compilation unit.

git-svn-id: https://gcc.gnu.org/svn/gcc/branches/ranger@278677 138bc75d-0d04-0410-961f-82ee72b054a4

3 files changed, 44 insertions, 0 deletions

diff --git a/gcc/toplev.c b/gcc/toplev.c
index d4583bac66c..cb335e97e3f 100644
--- a/gcc/toplev.c
+++ b/gcc/toplev.c
@@ -2112,6 +2112,7 @@ dump_memory_report (const char *header)
   dump_ggc_loc_statistics ();
   dump_alias_stats (stderr);
   dump_pta_stats (stderr);
+  dump_value_range_stats (stderr);
 }
 
 /* Clean up: close opened files, etc.  */
diff --git a/gcc/value-range.cc b/gcc/value-range.cc
index e6abf639511..e99b68a2c45 100644
--- a/gcc/value-range.cc
+++ b/gcc/value-range.cc
@@ -256,6 +256,8 @@ widest_irange::widest_irange (const irange &other)
 
 widest_irange::~widest_irange ()
 {
+  if (CHECKING_P)
+    stats_register_use ();
   if (m_blob)
     free (m_blob);
 }
@@ -309,6 +311,39 @@ widest_irange::invert ()
   resize_if_needed (size);
   irange::invert ();
 }
+
+int widest_irange::stats_used_buckets[11];
+
+void
+widest_irange::stats_register_use (void)
+{
+  int n = num_pairs ();
+  if (n < 10)
+    stats_used_buckets[n]++;
+  else
+    stats_used_buckets[10]++;
+}
+
+void
+widest_irange::stats_dump (FILE *file)
+{
+  fprintf (file, "\nwidest_irange stats:\n");
+  for (int i = 0; i < 11; ++i)
+    {
+      if (stats_used_buckets[i] == 0)
+	continue;
+      if (i < 10)
+	fprintf (file, "%2d sub-ranges: %d\n", i, stats_used_buckets[i]);
+      else
+	fprintf (file, "10+ sub-ranges: %d\n", stats_used_buckets[i]);
+    }
+}
+
+void
+dump_value_range_stats (FILE *file)
+{
+  widest_irange::stats_dump (file);
+}
 
 void
 vrange::set_undefined ()
diff --git a/gcc/value-range.h b/gcc/value-range.h
index 8d0d796c3b6..8cc71b16005 100644
--- a/gcc/value-range.h
+++ b/gcc/value-range.h
@@ -180,11 +180,18 @@ public:
 
   virtual void union_ (const vrange &);
   virtual void invert ();
+#if CHECKING_P
+  static void stats_dump (FILE *);
+#endif
 private:
   static const unsigned m_sub_ranges_in_local_storage = 5;
   void init_widest_irange ();
   void resize_if_needed (unsigned);
 
+  // Memory usage stats.
+  void stats_register_use (void);
+  static int stats_used_buckets[11];
+
   tree *m_blob;
   tree m_ranges[m_sub_ranges_in_local_storage*2];
 };
@@ -197,6 +204,7 @@ extern bool range_has_numeric_bounds_p (const irange *);
 extern bool ranges_from_anti_range (const value_range *,
 				    value_range *, value_range *);
 extern void dump_value_range (FILE *, const vrange *);
+extern void dump_value_range_stats (FILE *);
 extern bool vrp_val_is_min (const_tree);
 extern bool vrp_val_is_max (const_tree);
 extern tree vrp_val_min (const_tree);