[gtk/wip/matthiasc/css-values: 1/23] Revert "css: Faster matching for simple selectors"

[Matthias Clasen <matthiasc src gnome org>]

commit a5dc2caa13698db396305d53b3ec05763c8aa361
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Jan 14 16:59:27 2020 -0500

    Revert "css: Faster matching for simple selectors"
    
    This reverts commit 05f7d68e297107b05460130fa2f40ee2b2029e39.

 gtk/gtkcssmatcher.c        |  40 +++--------
 gtk/gtkcssmatcherprivate.h |  18 ++---
 gtk/gtkcssselector.c       | 163 +++------------------------------------------
 3 files changed, 28 insertions(+), 193 deletions(-)
---
diff --git a/gtk/gtkcssmatcher.c b/gtk/gtkcssmatcher.c
index a1007c1217..0fee1ea6c3 100644
--- a/gtk/gtkcssmatcher.c
+++ b/gtk/gtkcssmatcher.c
@@ -160,14 +160,14 @@ gtk_css_matcher_widget_path_has_position (const GtkCssMatcher *matcher,
 }
 
 static const GtkCssMatcherClass GTK_CSS_MATCHER_WIDGET_PATH = {
-  GTK_CSS_MATCHER_TYPE_WIDGET_PATH,
   gtk_css_matcher_widget_path_get_parent,
   gtk_css_matcher_widget_path_get_previous,
   gtk_css_matcher_widget_path_get_state,
   gtk_css_matcher_widget_path_has_name,
   gtk_css_matcher_widget_path_has_class,
   gtk_css_matcher_widget_path_has_id,
-  gtk_css_matcher_widget_path_has_position
+  gtk_css_matcher_widget_path_has_position,
+  FALSE
 };
 
 gboolean
@@ -336,14 +336,14 @@ gtk_css_matcher_node_has_position (const GtkCssMatcher *matcher,
 }
 
 static const GtkCssMatcherClass GTK_CSS_MATCHER_NODE = {
-  GTK_CSS_MATCHER_TYPE_NODE,
   gtk_css_matcher_node_get_parent,
   gtk_css_matcher_node_get_previous,
   gtk_css_matcher_node_get_state,
   gtk_css_matcher_node_has_name,
   gtk_css_matcher_node_has_class,
   gtk_css_matcher_node_has_id,
-  gtk_css_matcher_node_has_position
+  gtk_css_matcher_node_has_position,
+  FALSE
 };
 
 void
@@ -421,14 +421,14 @@ gtk_css_matcher_any_has_position (const GtkCssMatcher *matcher,
 }
 
 static const GtkCssMatcherClass GTK_CSS_MATCHER_ANY = {
-  GTK_CSS_MATCHER_TYPE_ANY,
   gtk_css_matcher_any_get_parent,
   gtk_css_matcher_any_get_previous,
   gtk_css_matcher_any_get_state,
   gtk_css_matcher_any_has_name,
   gtk_css_matcher_any_has_class,
   gtk_css_matcher_any_has_id,
-  gtk_css_matcher_any_has_position
+  gtk_css_matcher_any_has_position,
+  TRUE
 };
 
 void
@@ -496,15 +496,15 @@ gtk_css_matcher_superset_has_position (const GtkCssMatcher *matcher,
   return TRUE;
 }
 
-static const GtkCssMatcherClass GTK_CSS_MATCHER_SUPERSET = {
-  GTK_CSS_MATCHER_TYPE_SUPERSET,
+static const GtkCssMatcherClass GTK_CSS_MATCHER_SUPERSET2 = {
   gtk_css_matcher_superset_get_parent,
   gtk_css_matcher_superset_get_previous,
   gtk_css_matcher_superset_get_state,
   gtk_css_matcher_superset_has_name,
   gtk_css_matcher_superset_has_class,
   gtk_css_matcher_superset_has_id,
-  gtk_css_matcher_superset_has_position
+  gtk_css_matcher_superset_has_position,
+  FALSE
 };
 
 void
@@ -516,27 +516,8 @@ _gtk_css_matcher_superset_init (GtkCssMatcher       *matcher,
   g_return_if_fail (subset != NULL);
   g_return_if_fail ((relevant & ~(GTK_CSS_CHANGE_CLASS | GTK_CSS_CHANGE_NAME | GTK_CSS_CHANGE_POSITION | 
GTK_CSS_CHANGE_STATE)) == 0);
 
-  switch (subset->klass->matcher_type)
-    {
-    case GTK_CSS_MATCHER_TYPE_NODE:
-      matcher->node = subset->node;
-      if (!(relevant & GTK_CSS_CHANGE_STATE))
-        matcher->node.node_state = gtk_css_matcher_superset_get_state (matcher);
-      break;
-    case GTK_CSS_MATCHER_TYPE_WIDGET_PATH:
-      matcher->path = subset->path;
-      break;
-    case GTK_CSS_MATCHER_TYPE_ANY:
-      break;
-    case GTK_CSS_MATCHER_TYPE_SUPERSET:
-    default:
-      g_assert_not_reached ();
-      break;
-    }
-
-  *klass = GTK_CSS_MATCHER_SUPERSET;
+  *klass = GTK_CSS_MATCHER_SUPERSET2;
 
-  klass->matcher_type = subset->klass->matcher_type;
   if (relevant & GTK_CSS_CHANGE_CLASS)
     klass->has_class = subset->klass->has_class;
   if (relevant & GTK_CSS_CHANGE_NAME)
@@ -548,5 +529,6 @@ _gtk_css_matcher_superset_init (GtkCssMatcher       *matcher,
   if (relevant & GTK_CSS_CHANGE_STATE)
     klass->get_state = subset->klass->get_state;
 
+  *matcher = *subset;
   matcher->klass = klass;
 }
diff --git a/gtk/gtkcssmatcherprivate.h b/gtk/gtkcssmatcherprivate.h
index 89c889bd61..6f5e9d195c 100644
--- a/gtk/gtkcssmatcherprivate.h
+++ b/gtk/gtkcssmatcherprivate.h
@@ -29,15 +29,7 @@ typedef struct _GtkCssMatcherSuperset GtkCssMatcherSuperset;
 typedef struct _GtkCssMatcherWidgetPath GtkCssMatcherWidgetPath;
 typedef struct _GtkCssMatcherClass GtkCssMatcherClass;
 
-typedef enum {
-  GTK_CSS_MATCHER_TYPE_WIDGET_PATH,
-  GTK_CSS_MATCHER_TYPE_NODE,
-  GTK_CSS_MATCHER_TYPE_ANY,
-  GTK_CSS_MATCHER_TYPE_SUPERSET
-} GtkCssMatcherType;
-
 struct _GtkCssMatcherClass {
-  GtkCssMatcherType matcher_type;
   gboolean        (* get_parent)                  (GtkCssMatcher          *matcher,
                                                    const GtkCssMatcher    *child);
   gboolean        (* get_previous)                (GtkCssMatcher          *matcher,
@@ -54,6 +46,7 @@ struct _GtkCssMatcherClass {
                                                    gboolean               forward,
                                                    int                    a,
                                                    int                    b);
+  gboolean is_any;
 };
 
 struct _GtkCssMatcherWidgetPath {
@@ -74,10 +67,17 @@ struct _GtkCssMatcherNode {
   guint                     n_classes;
 };
 
+struct _GtkCssMatcherSuperset {
+  const GtkCssMatcherClass *klass;
+  const GtkCssMatcher      *subset;
+  GtkCssChange              relevant;
+};
+
 union _GtkCssMatcher {
   const GtkCssMatcherClass *klass;
   GtkCssMatcherWidgetPath   path;
   GtkCssMatcherNode         node;
+  GtkCssMatcherSuperset     superset;
 };
 
 gboolean          _gtk_css_matcher_init           (GtkCssMatcher          *matcher,
@@ -145,7 +145,7 @@ _gtk_css_matcher_has_position (const GtkCssMatcher *matcher,
 static inline gboolean
 _gtk_css_matcher_matches_any (const GtkCssMatcher *matcher)
 {
-  return matcher->klass->matcher_type == GTK_CSS_MATCHER_TYPE_ANY;
+  return matcher->klass->is_any;
 }
 
 
diff --git a/gtk/gtkcssselector.c b/gtk/gtkcssselector.c
index b1f7d3350c..2b7461e5eb 100644
--- a/gtk/gtkcssselector.c
+++ b/gtk/gtkcssselector.c
@@ -1803,91 +1803,6 @@ gtk_css_selectors_skip_initial_selector (GtkCssSelector *selector, const GtkCssS
   return (GtkCssSelector *)gtk_css_selector_previous (selector);
 }
 
-static inline gboolean
-match_node_name (const GtkCssMatcher *matcher,
-                 const char          *name)
-{
-  return matcher->node.node_name == name;
-}
-
-static inline gboolean
-match_node_id (const GtkCssMatcher *matcher,
-               const char          *id)
-{
-  return matcher->node.node_id == id;
-}
-
-static inline gboolean
-match_node_class (const GtkCssMatcher *matcher,
-                  GQuark               class_name)
-{
-  const GQuark *classes = matcher->node.classes;
-
-  switch (matcher->node.n_classes)
-    {
-    case 3:
-      if (classes[2] == class_name)
-        return TRUE;
-      G_GNUC_FALLTHROUGH;
-
-    case 2:
-      if (classes[1] == class_name)
-        return TRUE;
-      G_GNUC_FALLTHROUGH;
-
-    case 1:
-      if (classes[0] == class_name)
-        return TRUE;
-      G_GNUC_FALLTHROUGH;
-
-    case 0:
-      return FALSE;
-
-    default:
-      return gtk_css_node_has_class (matcher->node.node, class_name);
-    }
-
-  return FALSE;
-}
-
-static inline gboolean
-match_node_state (const GtkCssMatcher *matcher,
-                  GtkStateFlags        state)
-{
-  return (matcher->node.node_state & state) == state;
-}
-
-static inline gboolean
-gtk_css_selector_match_node (const GtkCssSelector *selector,
-                             const GtkCssMatcher  *matcher)
-{
-  if (selector->class == &GTK_CSS_SELECTOR_NAME)
-    return match_node_name (matcher, selector->name.name);
-
-  if (selector->class == &GTK_CSS_SELECTOR_CLASS)
-    return match_node_class (matcher, selector->style_class.style_class);
-
-  if (selector->class == &GTK_CSS_SELECTOR_PSEUDOCLASS_STATE)
-    return match_node_state (matcher, selector->state.state);
-
-  if (selector->class == &GTK_CSS_SELECTOR_ID)
-    return match_node_id (matcher, selector->id.name);
-
-  if (selector->class == &GTK_CSS_SELECTOR_NOT_NAME)
-    return !match_node_name (matcher, selector->name.name);
-
-  if (selector->class == &GTK_CSS_SELECTOR_NOT_CLASS)
-    return !match_node_class (matcher, selector->style_class.style_class);
-
-  if (selector->class == &GTK_CSS_SELECTOR_NOT_PSEUDOCLASS_STATE)
-    return !match_node_state (matcher, selector->state.state);
-
-  if (selector->class == &GTK_CSS_SELECTOR_NOT_ID)
-    return !match_node_id (matcher, selector->id.name);
-
-  return gtk_css_selector_match (selector, matcher);
-}
-
 static gboolean
 gtk_css_selector_tree_match_foreach (const GtkCssSelector *selector,
                                      const GtkCssMatcher  *matcher,
@@ -1909,42 +1824,15 @@ gtk_css_selector_tree_match_foreach (const GtkCssSelector *selector,
   return FALSE;
 }
 
-static gboolean
-gtk_css_selector_tree_match_node_foreach (const GtkCssSelector *selector,
-                                          const GtkCssMatcher  *matcher,
-                                          gpointer              res)
-{
-  const GtkCssSelectorTree *tree = (const GtkCssSelectorTree *) selector;
-  const GtkCssSelectorTree *prev;
-
-  if (!gtk_css_selector_match_node (selector, matcher))
-    return FALSE;
-
-  gtk_css_selector_tree_found_match (tree, res);
-
-  for (prev = gtk_css_selector_tree_get_previous (tree);
-       prev != NULL;
-       prev = gtk_css_selector_tree_get_sibling (prev))
-    gtk_css_selector_foreach (&prev->selector, matcher, gtk_css_selector_tree_match_node_foreach, res);
-
-  return FALSE;
-}
-
 GPtrArray *
 _gtk_css_selector_tree_match_all (const GtkCssSelectorTree *tree,
                                  const GtkCssMatcher *matcher)
 {
   GPtrArray *array = NULL;
-  GtkCssSelectorForeachFunc func;
-
-  if (matcher->klass->matcher_type == GTK_CSS_MATCHER_TYPE_NODE)
-    func = gtk_css_selector_tree_match_node_foreach;
-  else
-    func = gtk_css_selector_tree_match_foreach;
 
   for (; tree != NULL;
-         tree = gtk_css_selector_tree_get_sibling (tree))
-      gtk_css_selector_foreach (&tree->selector, matcher, func, &array);
+       tree = gtk_css_selector_tree_get_sibling (tree))
+    gtk_css_selector_foreach (&tree->selector, matcher, gtk_css_selector_tree_match_foreach, &array);
 
   return array;
 }
@@ -1980,14 +1868,13 @@ static GtkCssChange
 gtk_css_selector_tree_get_change (const GtkCssSelectorTree *tree,
                                  const GtkCssMatcher      *matcher)
 {
-  const GtkCssSelector *selector = &tree->selector;
   GtkCssChange change = 0;
   const GtkCssSelectorTree *prev;
 
-  if (!gtk_css_selector_match (selector, matcher))
+  if (!gtk_css_selector_match (&tree->selector, matcher))
     return 0;
 
-  if (!selector->class->is_simple)
+  if (!tree->selector.class->is_simple)
     return tree->change | GTK_CSS_CHANGE_GOT_MATCH;
 
   for (prev = gtk_css_selector_tree_get_previous (tree);
@@ -1996,32 +1883,7 @@ gtk_css_selector_tree_get_change (const GtkCssSelectorTree *tree,
     change |= gtk_css_selector_tree_get_change (prev, matcher);
 
   if (change || gtk_css_selector_tree_get_matches (tree))
-    change = tree->selector.class->get_change (selector, change & ~GTK_CSS_CHANGE_GOT_MATCH) | 
GTK_CSS_CHANGE_GOT_MATCH;
-
-  return change;
-}
-
-static GtkCssChange
-gtk_css_selector_tree_get_change_node (const GtkCssSelectorTree *tree,
-                                      const GtkCssMatcher      *matcher)
-{
-  const GtkCssSelector *selector = &tree->selector;
-  GtkCssChange change = 0;
-  const GtkCssSelectorTree *prev;
-
-  if (!gtk_css_selector_match_node (selector, matcher))
-    return 0;
-
-  if (!selector->class->is_simple)
-    return tree->change | GTK_CSS_CHANGE_GOT_MATCH;
-
-  for (prev = gtk_css_selector_tree_get_previous (tree);
-       prev != NULL;
-       prev = gtk_css_selector_tree_get_sibling (prev))
-    change |= gtk_css_selector_tree_get_change_node (prev, matcher);
-
-  if (change || gtk_css_selector_tree_get_matches (tree))
-    change = tree->selector.class->get_change (selector, change & ~GTK_CSS_CHANGE_GOT_MATCH) | 
GTK_CSS_CHANGE_GOT_MATCH;
+    change = tree->selector.class->get_change (&tree->selector, change & ~GTK_CSS_CHANGE_GOT_MATCH) | 
GTK_CSS_CHANGE_GOT_MATCH;
 
   return change;
 }
@@ -2041,18 +1903,9 @@ _gtk_css_selector_tree_get_change_all (const GtkCssSelectorTree *tree,
   change = 0;
 
   /* no need to foreach here because we abort for non-simple selectors */
-  if (matcher->klass->matcher_type == GTK_CSS_MATCHER_TYPE_NODE)
-    {
-      for (; tree != NULL;
-           tree = gtk_css_selector_tree_get_sibling (tree))
-         change |= gtk_css_selector_tree_get_change_node (tree, matcher);
-    }
-  else
-    {
-      for (; tree != NULL;
-           tree = gtk_css_selector_tree_get_sibling (tree))
-         change |= gtk_css_selector_tree_get_change (tree, matcher);
-    }
+  for (; tree != NULL;
+       tree = gtk_css_selector_tree_get_sibling (tree))
+    change |= gtk_css_selector_tree_get_change (tree, matcher);
 
   /* Never return reserved bit set */
   return change & ~GTK_CSS_CHANGE_RESERVED_BIT;