[gtk/css-lookup-caching] wip: Count duplicate lookups

[Matthias Clasen <matthiasc src gnome org>]

commit b388fd688a3c87552063388d902eaf9abb4c0c19
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Feb 11 18:55:17 2020 -0500

    wip: Count duplicate lookups

 gtk/gtkcsslookup.c        | 113 ++++++++++++++++++++++++++++++++++++++++++++++
 gtk/gtkcsslookupprivate.h |   2 +
 gtk/gtkcssstaticstyle.c   |   4 ++
 3 files changed, 119 insertions(+)
---
diff --git a/gtk/gtkcsslookup.c b/gtk/gtkcsslookup.c
index 7e52359b65..8be44da66f 100644
--- a/gtk/gtkcsslookup.c
+++ b/gtk/gtkcsslookup.c
@@ -25,6 +25,77 @@
 #include "gtkprivate.h"
 
 
+static GHashTable *lookups;
+
+static gboolean
+gtk_css_lookup_equal (const GtkCssLookup *l1,
+                      const GtkCssLookup *l2)
+{
+  int i;
+
+  if (!_gtk_bitmask_equals (l1->set_values, l2->set_values))
+    return FALSE;
+
+  if (l1->values == NULL && l2->values == NULL)
+    return TRUE;
+
+  if (l1->values == NULL || l2->values == NULL)
+    return FALSE;
+
+  if (l1->values->len != l2->values->len)
+    return FALSE;
+
+  for (i = 0; i < l1->values->len; i++)
+    {
+      GtkCssLookupValue *v1 = g_ptr_array_index (l1->values, i);
+      GtkCssLookupValue *v2 = g_ptr_array_index (l2->values, i);
+
+      if (!_gtk_css_value_equal (v1->value, v2->value))
+        return FALSE;
+    }
+
+  return TRUE;
+}
+
+static guint
+gtk_css_lookup_hash (const GtkCssLookup *l)
+{
+  int i;
+  guint h;
+
+  if (l->values == NULL)
+    return 0;
+
+  h = 0;
+  for (i = 0; i < l->values->len; i++)
+    {
+      GtkCssLookupValue *v = g_ptr_array_index (l->values, i);
+      char *s = _gtk_css_value_to_string (v->value);
+      h += g_str_hash (s);
+      g_free (s);
+    }
+
+  return h;
+}
+
+static gboolean
+dump_lookups (gpointer data)
+{
+  GHashTableIter iter;
+  GtkCssLookup *key;
+  gpointer value;
+
+  g_print ("lookup counts: ");
+  g_hash_table_iter_init (&iter, lookups);
+  while (g_hash_table_iter_next (&iter, (gpointer *)&key, (gpointer *)&value))
+    {
+      g_print ("%d ", GPOINTER_TO_INT (value));
+    }
+  g_print ("\n");
+
+  return G_SOURCE_CONTINUE;
+}
+
 GtkCssLookup *
 gtk_css_lookup_new (void)
 {
@@ -33,12 +104,50 @@ gtk_css_lookup_new (void)
   lookup->ref_count = 1;
   lookup->set_values = _gtk_bitmask_new ();
 
+  if (!lookups)
+    {
+      lookups = g_hash_table_new (gtk_css_lookup_hash, gtk_css_lookup_equal);
+      g_timeout_add (1000, dump_lookups, NULL);
+    }
+
   return lookup;
 }
 
+void
+gtk_css_lookup_register (GtkCssLookup *lookup)
+{
+  gint count;
+
+  count = GPOINTER_TO_INT (g_hash_table_lookup (lookups, lookup));
+  count++;
+
+  if (count == 1)
+    gtk_css_lookup_ref (lookup);
+
+  g_hash_table_insert (lookups, lookup, GINT_TO_POINTER (count));
+}
+
+static void
+gtk_css_lookup_unregister (GtkCssLookup *lookup)
+{
+  gint count;
+
+  count = GPOINTER_TO_INT (g_hash_table_lookup (lookups, lookup));
+  g_assert (count > 0);
+  if (count == 1)
+    g_hash_table_remove (lookups, lookup);
+  else
+    {
+      count--;
+      g_hash_table_insert (lookups, lookup, GINT_TO_POINTER (count));
+    }
+}
+
 static void
 gtk_css_lookup_free (GtkCssLookup *lookup)
 {
+  gtk_css_lookup_unregister (lookup);
+
   _gtk_bitmask_free (lookup->set_values);
   if (lookup->values)
     g_ptr_array_unref (lookup->values);
@@ -64,6 +173,10 @@ gtk_css_lookup_unref (GtkCssLookup *lookup)
 
   lookup->ref_count--;
 
+  if (lookup->ref_count == 1 &&
+      GPOINTER_TO_INT (g_hash_table_lookup (lookups, lookup)) == 1)
+    lookup->ref_count--;
+
   if (lookup->ref_count == 0)
     gtk_css_lookup_free (lookup);
 }
diff --git a/gtk/gtkcsslookupprivate.h b/gtk/gtkcsslookupprivate.h
index f73d8f56de..d2dd82cee4 100644
--- a/gtk/gtkcsslookupprivate.h
+++ b/gtk/gtkcsslookupprivate.h
@@ -77,6 +77,8 @@ gtk_css_lookup_get (GtkCssLookup *lookup,
   return NULL;
 } 
 
+void gtk_css_lookup_register (GtkCssLookup *lookup);
+
 G_END_DECLS
 
 #endif /* __GTK_CSS_LOOKUP_PRIVATE_H__ */
diff --git a/gtk/gtkcssstaticstyle.c b/gtk/gtkcssstaticstyle.c
index 8ccc1fe9f0..b3bdc476f2 100644
--- a/gtk/gtkcssstaticstyle.c
+++ b/gtk/gtkcssstaticstyle.c
@@ -970,6 +970,8 @@ gtk_css_lookup_resolve (GtkCssLookup      *lookup,
     gtk_css_other_values_new_compute (sstyle, provider, parent_style, lookup);
 }
 
+extern GHashTable *lookups;
+
 GtkCssStyle *
 gtk_css_static_style_new_compute (GtkStyleProvider             *provider,
                                   const GtkCountingBloomFilter *filter,
@@ -993,6 +995,8 @@ gtk_css_static_style_new_compute (GtkStyleProvider             *provider,
                                    node,
                                    lookup,
                                    change == 0 ? &change : NULL);
+
+      gtk_css_lookup_register (lookup);
     }
 
   result = g_object_new (GTK_TYPE_CSS_STATIC_STYLE, NULL);