css: Add fast-path for parent selector matching

Add a fast path for parent selector matching that uses a bloom filter to
quickly discard selectors that can't possibly match.

Keep in mind that we match using a bloom filter, so we might
accidentally include too many selectors when hash/bucket collisions
occur.
That's not a correctness problem though, because we'll do a real check
afterwards.

The idea for this change is taken from browsers, in particular WebKit.

1 files changed, 2 insertions, 0 deletions

diff --git a/gtk/gtkcssselectorprivate.h b/gtk/gtkcssselectorprivate.h
index 64a05b63f7..a1e265d5d2 100644
--- a/gtk/gtkcssselectorprivate.h
+++ b/gtk/gtkcssselectorprivate.h
@@ -18,6 +18,7 @@
 #ifndef __GTK_CSS_SELECTOR_PRIVATE_H__
 #define __GTK_CSS_SELECTOR_PRIVATE_H__
 
+#include "gtk/gtkcountingbloomfilterprivate.h"
 #include "gtk/gtkcsstypesprivate.h"
 #include "gtk/gtkcssparserprivate.h"
 
@@ -42,6 +43,7 @@ int               _gtk_css_selector_compare         (const GtkCssSelector   *a,
 
 void         _gtk_css_selector_tree_free             (GtkCssSelectorTree       *tree);
 GPtrArray *  _gtk_css_selector_tree_match_all        (const GtkCssSelectorTree *tree,
+                                                      const GtkCountingBloomFilter *filter,
 						      GtkCssNode               *node);
 GtkCssChange _gtk_css_selector_tree_get_change_all   (const GtkCssSelectorTree *tree,
 						      GtkCssNode               *node);