1 files changed, 78 insertions, 44 deletions

diff --git a/Source/JavaScriptCore/runtime/StructureTransitionTable.h b/Source/JavaScriptCore/runtime/StructureTransitionTable.h
index d66202364..3c0e8131f 100644
--- a/Source/JavaScriptCore/runtime/StructureTransitionTable.h
+++ b/Source/JavaScriptCore/runtime/StructureTransitionTable.h
@@ -10,10 +10,10 @@
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
- * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
@@ -23,14 +23,12 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
  */
 
-#ifndef StructureTransitionTable_h
-#define StructureTransitionTable_h
+#pragma once
 
 #include "IndexingType.h"
 #include "WeakGCMap.h"
 #include <wtf/HashFunctions.h>
-#include <wtf/OwnPtr.h>
-#include <wtf/text/StringImpl.h>
+#include <wtf/text/UniquedStringImpl.h>
 
 namespace JSC {
 
@@ -41,7 +39,7 @@ static const unsigned FirstInternalAttribute = 1 << 6; // Use for transitions th
 
 // Support for attributes used to indicate transitions not related to properties.
 // If any of these are used, the string portion of the key should be 0.
-enum NonPropertyTransition {
+enum class NonPropertyTransition : unsigned {
     AllocateUndecided,
     AllocateInt32,
     AllocateDouble,
@@ -49,56 +47,108 @@ enum NonPropertyTransition {
     AllocateArrayStorage,
     AllocateSlowPutArrayStorage,
     SwitchToSlowPutArrayStorage,
-    AddIndexedAccessors
+    AddIndexedAccessors,
+    PreventExtensions,
+    Seal,
+    Freeze
 };
 
 inline unsigned toAttributes(NonPropertyTransition transition)
 {
-    return transition + FirstInternalAttribute;
+    return static_cast<unsigned>(transition) + FirstInternalAttribute;
+}
+
+inline bool changesIndexingType(NonPropertyTransition transition)
+{
+    switch (transition) {
+    case NonPropertyTransition::AllocateUndecided:
+    case NonPropertyTransition::AllocateInt32:
+    case NonPropertyTransition::AllocateDouble:
+    case NonPropertyTransition::AllocateContiguous:
+    case NonPropertyTransition::AllocateArrayStorage:
+    case NonPropertyTransition::AllocateSlowPutArrayStorage:
+    case NonPropertyTransition::SwitchToSlowPutArrayStorage:
+    case NonPropertyTransition::AddIndexedAccessors:
+        return true;
+    default:
+        return false;
+    }
 }
 
 inline IndexingType newIndexingType(IndexingType oldType, NonPropertyTransition transition)
 {
     switch (transition) {
-    case AllocateUndecided:
+    case NonPropertyTransition::AllocateUndecided:
         ASSERT(!hasIndexedProperties(oldType));
         return oldType | UndecidedShape;
-    case AllocateInt32:
+    case NonPropertyTransition::AllocateInt32:
         ASSERT(!hasIndexedProperties(oldType) || hasUndecided(oldType));
         return (oldType & ~IndexingShapeMask) | Int32Shape;
-    case AllocateDouble:
+    case NonPropertyTransition::AllocateDouble:
         ASSERT(!hasIndexedProperties(oldType) || hasUndecided(oldType) || hasInt32(oldType));
         return (oldType & ~IndexingShapeMask) | DoubleShape;
-    case AllocateContiguous:
+    case NonPropertyTransition::AllocateContiguous:
         ASSERT(!hasIndexedProperties(oldType) || hasUndecided(oldType) || hasInt32(oldType) || hasDouble(oldType));
         return (oldType & ~IndexingShapeMask) | ContiguousShape;
-    case AllocateArrayStorage:
+    case NonPropertyTransition::AllocateArrayStorage:
         ASSERT(!hasIndexedProperties(oldType) || hasUndecided(oldType) || hasInt32(oldType) || hasDouble(oldType) || hasContiguous(oldType));
         return (oldType & ~IndexingShapeMask) | ArrayStorageShape;
-    case AllocateSlowPutArrayStorage:
+    case NonPropertyTransition::AllocateSlowPutArrayStorage:
         ASSERT(!hasIndexedProperties(oldType) || hasUndecided(oldType) || hasInt32(oldType) || hasDouble(oldType) || hasContiguous(oldType) || hasContiguous(oldType));
         return (oldType & ~IndexingShapeMask) | SlowPutArrayStorageShape;
-    case SwitchToSlowPutArrayStorage:
-        ASSERT(hasFastArrayStorage(oldType));
+    case NonPropertyTransition::SwitchToSlowPutArrayStorage:
+        ASSERT(hasArrayStorage(oldType));
         return (oldType & ~IndexingShapeMask) | SlowPutArrayStorageShape;
-    case AddIndexedAccessors:
+    case NonPropertyTransition::AddIndexedAccessors:
         return oldType | MayHaveIndexedAccessors;
     default:
-        RELEASE_ASSERT_NOT_REACHED();
         return oldType;
     }
 }
 
+inline bool preventsExtensions(NonPropertyTransition transition)
+{
+    switch (transition) {
+    case NonPropertyTransition::PreventExtensions:
+    case NonPropertyTransition::Seal:
+    case NonPropertyTransition::Freeze:
+        return true;
+    default:
+        return false;
+    }
+}
+
+inline bool setsDontDeleteOnAllProperties(NonPropertyTransition transition)
+{
+    switch (transition) {
+    case NonPropertyTransition::Seal:
+    case NonPropertyTransition::Freeze:
+        return true;
+    default:
+        return false;
+    }
+}
+
+inline bool setsReadOnlyOnNonAccessorProperties(NonPropertyTransition transition)
+{
+    switch (transition) {
+    case NonPropertyTransition::Freeze:
+        return true;
+    default:
+        return false;
+    }
+}
+
 class StructureTransitionTable {
     static const intptr_t UsingSingleSlotFlag = 1;
 
     
     struct Hash {
-        typedef std::pair<StringImpl*, unsigned> Key;
+        typedef std::pair<UniquedStringImpl*, unsigned> Key;
         
         static unsigned hash(const Key& p)
         {
-            return PtrHash<StringImpl*>::hash(p.first) + p.second;
+            return PtrHash<UniquedStringImpl*>::hash(p.first) + p.second;
         }
 
         static bool equal(const Key& a, const Key& b)
@@ -130,11 +180,13 @@ public:
         WeakSet::deallocate(impl);
     }
 
-    inline void add(VM&, Structure*);
-    inline bool contains(StringImpl* rep, unsigned attributes) const;
-    inline Structure* get(StringImpl* rep, unsigned attributes) const;
+    void add(VM&, Structure*);
+    bool contains(UniquedStringImpl*, unsigned attributes) const;
+    Structure* get(UniquedStringImpl*, unsigned attributes) const;
 
 private:
+    friend class SingleSlotTransitionWeakOwner;
+
     bool isUsingSingleSlot() const
     {
         return m_data & UsingSingleSlotFlag;
@@ -165,28 +217,10 @@ private:
         ASSERT(!isUsingSingleSlot());
     }
 
-    Structure* singleTransition() const
-    {
-        ASSERT(isUsingSingleSlot());
-        if (WeakImpl* impl = this->weakImpl()) {
-            if (impl->state() == WeakImpl::Live)
-                return reinterpret_cast<Structure*>(impl->jsValue().asCell());
-        }
-        return 0;
-    }
-    
-    void setSingleTransition(VM&, Structure* structure)
-    {
-        ASSERT(isUsingSingleSlot());
-        if (WeakImpl* impl = this->weakImpl())
-            WeakSet::deallocate(impl);
-        WeakImpl* impl = WeakSet::allocate(reinterpret_cast<JSCell*>(structure));
-        m_data = reinterpret_cast<intptr_t>(impl) | UsingSingleSlotFlag;
-    }
+    Structure* singleTransition() const;
+    void setSingleTransition(Structure*);
 
     intptr_t m_data;
 };
 
 } // namespace JSC
-
-#endif // StructureTransitionTable_h