Changeset 50254 in webkit for trunk/JavaScriptCore/runtime/Structure.h

Timestamp:

Oct 28, 2009, 6:25:02 PM (16 years ago)

Author:

[email protected]

Message:

Improve for..in enumeration performance
​https://bugs.webkit.org/show_bug.cgi?id=30887

Reviewed by Geoff Garen.

Improve indexing of an object with a for..in iterator by
identifying cases where get_by_val is being used with a iterator
as the subscript and replace it with a new get_by_pname
bytecode. get_by_pname then optimizes lookups that directly access
the base object.

File:

• trunk/JavaScriptCore/runtime/Structure.h (modified) (4 diffs)

trunk/JavaScriptCore/runtime/Structure.h

@@ -96 +96 @@
 
         void growPropertyStorageCapacity();
-        size_t propertyStorageCapacity() const { return m_propertyStorageCapacity; }
-        size_t propertyStorageSize() const { return m_propertyTable ? m_propertyTable->keyCount + m_propertyTable->anonymousSlotCount + (m_propertyTable->deletedOffsets ? m_propertyTable->deletedOffsets->size() : 0) : m_offset + 1; }
+        unsigned propertyStorageCapacity() const { return m_propertyStorageCapacity; }
+        unsigned propertyStorageSize() const { return m_propertyTable ? m_propertyTable->keyCount + m_propertyTable->anonymousSlotCount + (m_propertyTable->deletedOffsets ? m_propertyTable->deletedOffsets->size() : 0) : m_offset + 1; }
         bool isUsingInlineStorage() const;
 
@@ -120 +120 @@
         void setHasGetterSetterProperties(bool hasGetterSetterProperties) { m_hasGetterSetterProperties = hasGetterSetterProperties; }
 
+        bool hasNonEnumerableProperties() const { return m_hasNonEnumerableProperties; }
+
+        bool hasAnonymousSlots() const { return m_propertyTable && m_propertyTable->anonymousSlotCount; }
+        
         bool isEmpty() const { return m_propertyTable ? !m_propertyTable->keyCount : m_offset == noOffset; }
 
@@ -191 +195 @@
         PropertyMapHashTable* m_propertyTable;
 
-        size_t m_propertyStorageCapacity;
+        uint32_t m_propertyStorageCapacity;
         signed char m_offset;
 
@@ -197 +201 @@
         bool m_isPinnedPropertyTable : 1;
         bool m_hasGetterSetterProperties : 1;
+        bool m_hasNonEnumerableProperties : 1;
 #if COMPILER(WINSCW)
         // Workaround for Symbian WINSCW compiler that cannot resolve unsigned type of the declared