Changeset 36401 in webkit for trunk/JavaScriptCore/kjs/StructureID.h

Timestamp:

Sep 14, 2008, 1:18:49 AM (17 years ago)

Author:

[email protected]

Message:

Bug 20821: Cache property transitions to speed up object initialization
​https://bugs.webkit.org/show_bug.cgi?id=20821

Reviewed by Cameron Zwarich.

Implement a transition cache to improve the performance of new properties
being added to objects. This is extremely beneficial in constructors and
shows up as a 34% improvement on access-binary-trees in SunSpider (0.8%
overall)

File:

• trunk/JavaScriptCore/kjs/StructureID.h (modified) (3 diffs)

trunk/JavaScriptCore/kjs/StructureID.h

@@ -73 +73 @@
     class StructureID : public RefCounted<StructureID> {
     public:
+        friend class CTI;
         static PassRefPtr<StructureID> create(JSValue* prototype, JSType type = ObjectType)
         {
@@ -98 +99 @@
         JSValue* storedPrototype() const { return m_prototype; }
         JSValue* prototypeForLookup(ExecState*); 
-        
+
+        StructureID* previousID() const { return m_previous.get(); }
+
         void setCachedPrototypeChain(PassRefPtr<StructureIDChain> cachedPrototypeChain) { m_cachedPrototypeChain = cachedPrototypeChain; }
         StructureIDChain* cachedPrototypeChain() const { return m_cachedPrototypeChain.get(); }
@@ -104 +107 @@
         const PropertyMap& propertyMap() const { return m_propertyMap; }
         PropertyMap& propertyMap() { return m_propertyMap; }
+
+        static void transitionTo(StructureID* oldStructureID, StructureID* newStructureID, JSObject* slotBase);
 
     private: