Changeset 172517 in webkit

Timestamp:

Aug 13, 2014, 3:13:43 AM (11 years ago)

Author:

Antti Koivisto

Message:

Don't recurse into non-rendered subtrees when computing style
​https://bugs.webkit.org/show_bug.cgi?id=135844

Reviewed by Andreas Kling.

• style/StyleResolveTree.cpp:

(WebCore::Style::resetStyleForNonRenderedDescendants):

Do a simple reset of the style dirty bits and any computed style in non-renderer subtrees.

(WebCore::Style::attachRenderTree):
(WebCore::Style::resolveTree):

Don't recurse into descendants if the element does not create a renderer.
We didn't compute style anyway in such subtrees.

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• style/StyleResolveTree.cpp (modified) (7 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2014-08-13  Antti Koivisto  <antti@apple.com>
+
+        Don't recurse into non-rendered subtrees when computing style
+        https://bugs.webkit.org/show_bug.cgi?id=135844
+
+        Reviewed by Andreas Kling.
+
+        * style/StyleResolveTree.cpp:
+        (WebCore::Style::resetStyleForNonRenderedDescendants):
+        
+        Do a simple reset of the style dirty bits and any computed style in non-renderer subtrees.
+
+        (WebCore::Style::attachRenderTree):
+        (WebCore::Style::resolveTree):
+        
+        Don't recurse into descendants if the element does not create a renderer.
+        We didn't compute style anyway in such subtrees.
+
 2014-08-11  Myles C. Maxfield  <mmaxfield@apple.com>
 

trunk/Source/WebCore/style/StyleResolveTree.cpp

@@ -556 +556 @@
 }
 
+static void resetStyleForNonRenderedDescendants(Element& current)
+{
+    ASSERT(!current.renderStyle());
+    for (auto& child : childrenOfType<Element>(current)) {
+        ASSERT(!child.renderer());
+        if (child.needsStyleRecalc()) {
+            child.resetComputedStyle();
+            child.clearNeedsStyleRecalc();
+        }
+        if (child.childNeedsStyleRecalc()) {
+            resetStyleForNonRenderedDescendants(child);
+            child.clearChildNeedsStyleRecalc();
+        }
+    }
+}
+
 static bool needsPseudoElement(Element& current, PseudoId pseudoId)
 {
@@ -583 +599 @@
     WidgetHierarchyUpdatesSuspensionScope suspendWidgetHierarchyUpdates;
 
+    if (isInsertionPoint(current)) {
+        attachDistributedChildren(toInsertionPoint(current), inheritedStyle, renderTreePosition);
+        current.clearNeedsStyleRecalc();
+        current.clearChildNeedsStyleRecalc();
+        return;
+    }
+
     if (current.hasCustomStyleResolveCallbacks())
         current.willAttachRenderers();
@@ -588 +611 @@
     createRendererIfNeeded(current, inheritedStyle, renderTreePosition, resolvedStyle);
 
-    StyleResolverParentPusher parentPusher(&current);
-
-    RenderTreePosition childRenderTreePosition(current.renderer());
-    attachBeforeOrAfterPseudoElementIfNeeded(current, BEFORE, childRenderTreePosition);
-
-    if (ShadowRoot* shadowRoot = current.shadowRoot()) {
-        parentPusher.push();
-        attachShadowRoot(*shadowRoot);
-    } else if (current.firstChild())
-        parentPusher.push();
-
-    if (isInsertionPoint(current))
-        attachDistributedChildren(toInsertionPoint(current), inheritedStyle, renderTreePosition);
-    else
-        attachChildren(current, current.renderStyle(), childRenderTreePosition);
+    if (RenderStyle* style = current.renderStyle()) {
+        StyleResolverParentPusher parentPusher(&current);
+
+        RenderTreePosition childRenderTreePosition(current.renderer());
+        attachBeforeOrAfterPseudoElementIfNeeded(current, BEFORE, childRenderTreePosition);
+
+        if (ShadowRoot* shadowRoot = current.shadowRoot()) {
+            parentPusher.push();
+            attachShadowRoot(*shadowRoot);
+        } else if (current.firstChild())
+            parentPusher.push();
+
+        attachChildren(current, style, childRenderTreePosition);
+
+        if (AXObjectCache* cache = current.document().axObjectCache())
+            cache->updateCacheAfterNodeIsAttached(&current);
+
+        attachBeforeOrAfterPseudoElementIfNeeded(current, AFTER, childRenderTreePosition);
+
+        current.updateFocusAppearanceAfterAttachIfNeeded();
+    } else
+        resetStyleForNonRenderedDescendants(current);
 
     current.clearNeedsStyleRecalc();
     current.clearChildNeedsStyleRecalc();
-
-    if (AXObjectCache* cache = current.document().axObjectCache())
-        cache->updateCacheAfterNodeIsAttached(&current);
-
-    attachBeforeOrAfterPseudoElementIfNeeded(current, AFTER, childRenderTreePosition);
-
-    current.updateFocusAppearanceAfterAttachIfNeeded();
 
     if (current.hasCustomStyleResolveCallbacks())
@@ -867 +890 @@
     ASSERT(change != Detach);
 
+    if (isInsertionPoint(current)) {
+        current.clearNeedsStyleRecalc();
+        current.clearChildNeedsStyleRecalc();
+        return;
+    }
+
     if (current.hasCustomStyleResolveCallbacks()) {
         if (!current.willRecalcStyle(change))
@@ -885 +914 @@
         change = resolveLocal(current, inheritedStyle, renderTreePosition, change);
 
-    if (change != Detach) {
+    RenderStyle* style = current.renderStyle();
+
+    if (change != Detach && style) {
         StyleResolverParentPusher parentPusher(&current);
 
@@ -918 +949 @@
             if (change >= Inherit || childElement->childNeedsStyleRecalc() || childElement->needsStyleRecalc()) {
                 parentPusher.push();
-                resolveTree(*childElement, current.renderStyle(), childRenderTreePosition, change);
+                resolveTree(*childElement, style, childRenderTreePosition, change);
             }
             forceCheckOfNextElementSibling = childRulesChanged && hasDirectAdjacentRules;
@@ -926 +957 @@
         updateBeforeOrAfterPseudoElement(current, change, AFTER, childRenderTreePosition);
     }
+    if (change != Detach && !style)
+        resetStyleForNonRenderedDescendants(current);
 
     current.clearNeedsStyleRecalc();