From 8a5bb6cb5ff1bc032c5253880f2dbc934bdf6749 Mon Sep 17 00:00:00 2001
From: Matthias Clasen <mclasen@redhat.com>
Date: Tue, 11 Feb 2020 17:30:28 -0500
Subject: [PATCH] lookup: Merge rulesets more efficiently

Keep lookups sorted, and take advantage of the fact
that the rulesets are sorted, too. We can merge them
in a linear sweep.
---
 gtk/gtkcsslookup.c        | 60 +++++++++++++++++++++------------------
 gtk/gtkcsslookupprivate.h |  8 ++----
 gtk/gtkcssprovider.c      | 11 +------
 3 files changed, 36 insertions(+), 43 deletions(-)

diff --git a/gtk/gtkcsslookup.c b/gtk/gtkcsslookup.c
index bcce8d2a49..65d8e6d844 100644
--- a/gtk/gtkcsslookup.c
+++ b/gtk/gtkcsslookup.c
@@ -68,41 +68,45 @@ gtk_css_lookup_unref (GtkCssLookup *lookup)
     gtk_css_lookup_free (lookup);
 }
 
-gboolean
-gtk_css_lookup_is_missing (const GtkCssLookup *lookup,
-                           guint               id)
-{
-  gtk_internal_return_val_if_fail (lookup != NULL, FALSE);
-
-  return !_gtk_bitmask_get (lookup->set_values, id);
-}
-
-/**
- * _gtk_css_lookup_set:
- * @lookup: the lookup
- * @id: id of the property to set, see _gtk_style_property_get_id()
- * @section: (allow-none): The @section the value was defined in or %NULL
- * @value: the “cascading value” to use
+/*
+ * gtk_css_lookup_fill:
+ * @lookup: the #GtkCssLookup to populate
+ * @values: array of values to place into unpopulated slots in @lookup
+ * @n_values: the length of @values
  *
- * Sets the @value for a given @id. No value may have been set for @id
- * before. See _gtk_css_lookup_is_missing(). This function is used to
- * set the “winning declaration” of a lookup. Note that for performance
- * reasons @value and @section are not copied. It is your responsibility
- * to ensure they are kept alive until _gtk_css_lookup_free() is called.
- **/
+ * Add the @values to @lookup for properties for which
+ * @lookup does not have a value yet.
+ */
 void
-gtk_css_lookup_set (GtkCssLookup      *lookup,
-                    guint              id,
-                    GtkCssLookupValue *value)
+gtk_css_lookup_fill (GtkCssLookup      *lookup,
+                     GtkCssLookupValue *values,
+                     guint              n_values)
 {
+  int i, j;
+
   gtk_internal_return_if_fail (lookup != NULL);
-  gtk_internal_return_if_fail (value != NULL);
+  gtk_internal_return_if_fail (values != NULL);
 
   if (!lookup->values)
-    lookup->values = g_ptr_array_sized_new (16);
+    lookup->values = g_ptr_array_sized_new (MAX (16, n_values));
 
-  g_ptr_array_add (lookup->values, value);
-  lookup->set_values = _gtk_bitmask_set (lookup->set_values, id, TRUE);
+  for (i = 0, j = 0; j < n_values; j++, i++)
+    {
+      GtkCssLookupValue *v = NULL;
+
+      for (; i < lookup->values->len; i++)
+        {
+          v =  g_ptr_array_index (lookup->values, i);
+          if (v->id >= values[j].id)
+            break;
+        }
+
+      if (i == lookup->values->len || v->id > values[j].id)
+        {
+          g_ptr_array_insert (lookup->values, i, &values[j]);
+          lookup->set_values = _gtk_bitmask_set (lookup->set_values, values[j].id, TRUE);
+        }
+    }
 }
 
 GtkCssSection *
diff --git a/gtk/gtkcsslookupprivate.h b/gtk/gtkcsslookupprivate.h
index 2d61d9b2c0..b7113076a4 100644
--- a/gtk/gtkcsslookupprivate.h
+++ b/gtk/gtkcsslookupprivate.h
@@ -46,11 +46,9 @@ GtkCssLookup *           gtk_css_lookup_new (void);
 GtkCssLookup *           gtk_css_lookup_ref (GtkCssLookup *lookup);
 void                     gtk_css_lookup_unref (GtkCssLookup *lookup);
 
-gboolean                 gtk_css_lookup_is_missing              (const GtkCssLookup         *lookup,
-                                                                 guint                       id);
-void                     gtk_css_lookup_set                     (GtkCssLookup               *lookup,
-                                                                 guint                       id,
-                                                                 GtkCssLookupValue          *value);
+void                     gtk_css_lookup_fill                    (GtkCssLookup               *lookup,
+                                                                 GtkCssLookupValue          *values,
+                                                                 guint                       n_values);
 GtkCssSection *          gtk_css_lookup_get_section             (GtkCssLookup               *lookup,
                                                                  guint                       id);
 
diff --git a/gtk/gtkcssprovider.c b/gtk/gtkcssprovider.c
index 995f9fd40f..ac8ffcabe4 100644
--- a/gtk/gtkcssprovider.c
+++ b/gtk/gtkcssprovider.c
@@ -462,7 +462,6 @@ gtk_css_style_provider_lookup (GtkStyleProvider             *provider,
   GtkCssProvider *css_provider = GTK_CSS_PROVIDER (provider);
   GtkCssProviderPrivate *priv = gtk_css_provider_get_instance_private (css_provider);
   GtkCssRuleset *ruleset;
-  guint j;
   int i;
   GtkArray tree_rules_array;
   GtkCssRuleset *rules_stack[32];
@@ -484,15 +483,7 @@ gtk_css_style_provider_lookup (GtkStyleProvider             *provider,
           if (ruleset->styles == NULL)
             continue;
 
-          for (j = 0; j < ruleset->n_styles; j++)
-            {
-              guint id = ruleset->styles[j].id;
-
-              if (!gtk_css_lookup_is_missing (lookup, id))
-                continue;
-
-              gtk_css_lookup_set (lookup, id, (GtkCssLookupValue *)&ruleset->styles[j]);
-            }
+          gtk_css_lookup_fill (lookup, (GtkCssLookupValue *)ruleset->styles, ruleset->n_styles);
         }
 
       gtk_array_free (&tree_rules_array, NULL);