Changeset 96883 in webkit for trunk/Source/JavaScriptCore/runtime

Timestamp:

Oct 6, 2011, 5:47:21 PM (14 years ago)

Author:

[email protected]

Message:

Structure does not reset m_previous when pinning the property map
​https://bugs.webkit.org/show_bug.cgi?id=69583

Reviewed by Gavin Barraclough.

This is an 0.6% performance improvement in V8, and 0.2% overall.

• runtime/Structure.cpp:

(JSC::Structure::changePrototypeTransition):
(JSC::Structure::despecifyFunctionTransition):
(JSC::Structure::getterSetterTransition):
(JSC::Structure::toDictionaryTransition):
(JSC::Structure::preventExtensionsTransition):
(JSC::Structure::addPropertyWithoutTransition):
(JSC::Structure::removePropertyWithoutTransition):
(JSC::Structure::pin):

• runtime/Structure.h:

Location:

trunk/Source/JavaScriptCore/runtime

Files:

• Structure.cpp (modified) (7 diffs)
• Structure.h (modified) (1 diff)

trunk/Source/JavaScriptCore/runtime/Structure.cpp

@@ -370 +370 @@
     structure->materializePropertyMapIfNecessary(globalData);
     transition->m_propertyTable = structure->copyPropertyTable(globalData, transition);
-    transition->m_isPinnedPropertyTable = true;
+    transition->pin();
 
     return transition;
@@ -386 +386 @@
     structure->materializePropertyMapIfNecessary(globalData);
     transition->m_propertyTable = structure->copyPropertyTable(globalData, transition);
-    transition->m_isPinnedPropertyTable = true;
+    transition->pin();
 
     if (transition->m_specificFunctionThrashCount == maxSpecificFunctionThrashCount)
@@ -406 +406 @@
     structure->materializePropertyMapIfNecessary(globalData);
     transition->m_propertyTable = structure->copyPropertyTable(globalData, transition);
-    transition->m_isPinnedPropertyTable = true;
+    transition->pin();
 
     return transition;
@@ -419 +419 @@
     structure->materializePropertyMapIfNecessary(globalData);
     transition->m_propertyTable = structure->copyPropertyTable(globalData, transition);
-    transition->m_isPinnedPropertyTable = true;
     transition->m_dictionaryKind = kind;
+    transition->pin();
 
     return transition;
@@ -472 +472 @@
     structure->materializePropertyMapIfNecessary(globalData);
     transition->m_propertyTable = structure->copyPropertyTable(globalData, transition);
-    transition->m_isPinnedPropertyTable = true;
     transition->m_preventExtensions = true;
+    transition->pin();
 
     return transition;
@@ -550 +550 @@
 
     materializePropertyMapIfNecessary(globalData);
-
-    m_isPinnedPropertyTable = true;
+    
+    pin();
 
     size_t offset = putSpecificValue(globalData, propertyName, attributes, specificValue);
@@ -566 +566 @@
     materializePropertyMapIfNecessary(globalData);
 
-    m_isPinnedPropertyTable = true;
+    pin();
     size_t offset = remove(propertyName);
     return offset;
+}
+
+void Structure::pin()
+{
+    m_isPinnedPropertyTable = true;
+    m_previous.clear();
+    m_nameInPrevious.clear();
 }
 

trunk/Source/JavaScriptCore/runtime/Structure.h

@@ -237 +237 @@
 
         bool isValid(ExecState*, StructureChain* cachedPrototypeChain) const;
+        
+        void pin();
 
         static const int s_maxTransitionLength = 64;