Changeset 103855 in webkit for trunk/Source/WebCore/html/HTMLSelectElement.h

Timestamp:

Dec 30, 2011, 6:43:33 PM (13 years ago)

Author:

[email protected]

Message:

Cache and reuse the HTMLSelectElement.options collection.
<​http://webkit.org/b/75399>

Reviewed by Anders Carlsson.

Source/WebCore:

Let HTMLSelectElement::options() cache the returned collection and tie it to the
lifetime of the form. This shrinks HTMLSelectElement by sizeof(CollectionCache)
minus one pointer.

Test: fast/dom/select-options-collection-idempotence.html

fast/gc-9.html

• html/HTMLSelectElement.h:
• html/HTMLSelectElement.cpp:

(WebCore::HTMLSelectElement::options):

Cache the HTMLOptionsCollection returned by options() on the HTMLSelectElement.
Remove the per-select CollectionCache and let the collection manage that.

• html/HTMLOptionsCollection.h:
• html/HTMLOptionsCollection.cpp:

(WebCore::HTMLOptionsCollection::create):
(WebCore::HTMLOptionsCollection::HTMLOptionsCollection):

Tell the base class constructor to not retain the back-pointer to the element.

• html/HTMLSelectElement.cpp:

(WebCore::HTMLSelectElement::setRecalcListItems):

• html/HTMLOptionsCollection.cpp:

(WebCore::HTMLOptionsCollection::invalidateCache):

Added so HTMLSelectElement can invalidate the collection without triggering
unnecessary instantiation of a CollectionCache.

LayoutTests:

• Update gc-9.html to document the new lifetime characteristics of HTMLSelectElement.options.
• Add a test to verify that HTMLSelectElement.options returns the same object when called repeatedly.

• fast/dom/gc-9-expected.txt:
• fast/dom/gc-9.html:
• fast/dom/select-options-collection-idempotence-expected.txt: Added.
• fast/dom/select-options-collection-idempotence.html: Added.

File:

• trunk/Source/WebCore/html/HTMLSelectElement.h (modified) (3 diffs)

trunk/Source/WebCore/html/HTMLSelectElement.h

@@ -27 +27 @@
 #define HTMLSelectElement_h
 
-#include "CollectionCache.h"
 #include "Event.h"
 #include "HTMLFormControlElement.h"
+#include "HTMLOptionsCollection.h"
 #include <wtf/Vector.h>
 
@@ -84 +84 @@
     Node* namedItem(const AtomicString& name);
     Node* item(unsigned index);
-
-    CollectionCache* collectionInfo() { m_collectionInfo.checkConsistency(); return &m_collectionInfo; }
 
     void scrollToSelection();
@@ -177 +175 @@
     virtual void childrenChanged(bool changedByParser = false, Node* beforeChange = 0, Node* afterChange = 0, int childCountDelta = 0);
 
-    CollectionCache m_collectionInfo;
+    RefPtr<HTMLOptionsCollection> m_optionsCollection;
+
     // m_listItems contains HTMLOptionElement, HTMLOptGroupElement, and HTMLHRElement objects.
     mutable Vector<HTMLElement*> m_listItems;