Changeset 39502 in webkit for trunk/JavaScriptCore/runtime/Structure.cpp

Timestamp:

Dec 29, 2008, 4:28:40 PM (16 years ago)

Author:

[email protected]

Message:

2008-12-29 Sam Weinig <​[email protected]>

Reviewed by Oliver Hunt.

Patch for ​https://bugs.webkit.org/show_bug.cgi?id=23026
Move the deleted offsets vector into the PropertyMap

Saves 3 words per Structure.

• runtime/PropertyMapHashTable.h:
• runtime/Structure.cpp: (JSC::Structure::addPropertyTransition): (JSC::Structure::changePrototypeTransition): (JSC::Structure::getterSetterTransition): (JSC::Structure::toDictionaryTransition): (JSC::Structure::fromDictionaryTransition): (JSC::Structure::copyPropertyTable): (JSC::Structure::put): (JSC::Structure::remove): (JSC::Structure::rehashPropertyMapHashTable):
• runtime/Structure.h: (JSC::Structure::propertyStorageSize):

File:

• trunk/JavaScriptCore/runtime/Structure.cpp (modified) (11 diffs)

trunk/JavaScriptCore/runtime/Structure.cpp

@@ -39 +39 @@
 #endif
 
-#define DUMP_STRUCTURE_ID_STATISTICS 0
+#define DUMP_STRUCTURE_ID_STATISTICS 1
 
 #ifndef NDEBUG
@@ -102 +102 @@
             ++numberWithPropertyMaps;
             totalPropertyMapsSize += PropertyMapHashTable::allocationSize(structure->m_propertyTable->size);
+            if (structure->m_propertyTable->deletedOffsets)
+                totalPropertyMapsSize += (structure->m_propertyTable->deletedOffsets->capacity() * sizeof(unsigned)); 
         }
     }
@@ -379 +381 @@
     ASSERT(!structure->m_isDictionary);
     ASSERT(structure->typeInfo().type() == ObjectType);
-    ASSERT(structure->m_deletedOffsets.isEmpty());
     ASSERT(!Structure::addPropertyTransitionToExistingStructure(structure, propertyName, attributes, offset));
 
@@ -451 +452 @@
 
     transition->m_transitionCount = structure->m_transitionCount + 1;
-    transition->m_deletedOffsets = structure->m_deletedOffsets;
     transition->m_propertyStorageCapacity = structure->m_propertyStorageCapacity;
     transition->m_hasGetterSetterProperties = structure->m_hasGetterSetterProperties;
@@ -468 +468 @@
     RefPtr<Structure> transition = create(structure->storedPrototype(), structure->typeInfo());
     transition->m_transitionCount = structure->m_transitionCount + 1;
-    transition->m_deletedOffsets = structure->m_deletedOffsets;
     transition->m_propertyStorageCapacity = structure->m_propertyStorageCapacity;
     transition->m_hasGetterSetterProperties = transition->m_hasGetterSetterProperties;
@@ -487 +486 @@
     RefPtr<Structure> transition = create(structure->m_prototype, structure->typeInfo());
     transition->m_isDictionary = true;
-    transition->m_deletedOffsets = structure->m_deletedOffsets;
     transition->m_propertyStorageCapacity = structure->m_propertyStorageCapacity;
     transition->m_hasGetterSetterProperties = structure->m_hasGetterSetterProperties;
@@ -508 +506 @@
     // FIMXE: We can make this more efficient by canonicalizing the Structure (draining the
     // deleted offsets vector) before transitioning from dictionary. 
-    if (structure->m_deletedOffsets.isEmpty())
+    if (!structure->m_propertyTable || !structure->m_propertyTable->deletedOffsets || structure->m_propertyTable->deletedOffsets->isEmpty())
         structure->m_isDictionary = false;
 
@@ -604 +602 @@
     }
 
+    // Copy the deletedOffsets vector.
+    if (m_propertyTable->deletedOffsets)
+        newTable->deletedOffsets = new Vector<unsigned>(*m_propertyTable->deletedOffsets);
+
     return newTable;
 }
@@ -729 +731 @@
 
     unsigned newOffset;
-    if (!m_deletedOffsets.isEmpty()) {
-        newOffset = m_deletedOffsets.last();
-        m_deletedOffsets.removeLast();
+    if (m_propertyTable->deletedOffsets && !m_propertyTable->deletedOffsets->isEmpty()) {
+        newOffset = m_propertyTable->deletedOffsets->last();
+        m_propertyTable->deletedOffsets->removeLast();
     } else
         newOffset = m_propertyTable->keyCount;
@@ -799 +801 @@
     m_propertyTable->entries()[entryIndex - 1].attributes = 0;
     m_propertyTable->entries()[entryIndex - 1].offset = 0;
-    m_deletedOffsets.append(offset);
+
+    if (!m_propertyTable->deletedOffsets)
+        m_propertyTable->deletedOffsets = new Vector<unsigned>;
+    m_propertyTable->deletedOffsets->append(offset);
 
     ASSERT(m_propertyTable->keyCount >= 1);
@@ -904 +909 @@
     }
     m_propertyTable->lastIndexUsed = lastIndexUsed;
+    m_propertyTable->deletedOffsets = oldTable->deletedOffsets;
 
     fastFree(oldTable);