Changeset 169695 in webkit

Timestamp:

Jun 9, 2014 11:07:37 AM (10 years ago)

Author:

mark.lam@apple.com

Message:

Structure should initialize its previousID in its constructor.
<​https://webkit.org/b/133606>

Reviewed by Mark Hahnenberg.

Currently, the Structure constructor that takes a previous structure will
initialize its previousID to point to the previous structure's previousID.
This is incorrect. However, the caller of the Structure::create() factory
method (which instantiated the Structure) will later call setPreviousID()
to set the previousID to the correct previous structure. This makes the
code confusing to read and more error prone in that the structure relies
on client code to fix its invalid previousID.

This patch fixes this by making the Structure constructor initialize
previousID correctly.

• runtime/Structure.cpp:

(JSC::Structure::Structure):
(JSC::Structure::addPropertyTransition):
(JSC::Structure::nonPropertyTransition):

• runtime/Structure.h:
• runtime/StructureInlines.h:

(JSC::Structure::create):

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• runtime/Structure.cpp (modified) (4 diffs)
• runtime/Structure.h (modified) (1 diff)
• runtime/StructureInlines.h (modified) (1 diff)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2014-06-07  Mark Lam  <mark.lam@apple.com>
+
+        Structure should initialize its previousID in its constructor.
+        <https://webkit.org/b/133606>
+
+        Reviewed by Mark Hahnenberg.
+
+        Currently, the Structure constructor that takes a previous structure will
+        initialize its previousID to point to the previous structure's previousID.
+        This is incorrect.  However, the caller of the Structure::create() factory
+        method (which instantiated the Structure) will later call setPreviousID()
+        to set the previousID to the correct previous structure.  This makes the
+        code confusing to read and more error prone in that the structure relies
+        on client code to fix its invalid previousID.
+
+        This patch fixes this by making the Structure constructor initialize
+        previousID correctly.
+
+        * runtime/Structure.cpp:
+        (JSC::Structure::Structure):
+        (JSC::Structure::addPropertyTransition):
+        (JSC::Structure::nonPropertyTransition):
+        * runtime/Structure.h:
+        * runtime/StructureInlines.h:
+        (JSC::Structure::create):
+
 2014-06-06  Andreas Kling  <akling@apple.com>
 

trunk/Source/JavaScriptCore/runtime/Structure.cpp

@@ -212 +212 @@
 }
 
-Structure::Structure(VM& vm, const Structure* previous)
+Structure::Structure(VM& vm, Structure* previous)
     : JSCell(vm, vm.structureStructure.get())
     , m_prototype(vm, this, previous->storedPrototype())
@@ -237 +237 @@
     if (previous->typeInfo().structureHasRareData() && previous->rareData()->needsCloning())
         cloneRareDataFrom(vm, previous);
-    else if (previous->previousID())
-        m_previousOrRareData.set(vm, this, previous->previousID());
+    setPreviousID(vm, this, previous);
 
     previous->notifyTransitionFromThisStructure();
@@ -460 +459 @@
 
     transition->m_cachedPrototypeChain.setMayBeNull(vm, transition, structure->m_cachedPrototypeChain.get());
-    transition->setPreviousID(vm, transition, structure);
     transition->m_nameInPrevious = propertyName.uid();
     transition->m_attributesInPrevious = attributes;
@@ -673 +671 @@
     
     Structure* transition = create(vm, structure);
-    transition->setPreviousID(vm, transition, structure);
     transition->m_attributesInPrevious = attributes;
     transition->m_blob.setIndexingType(indexingType);

trunk/Source/JavaScriptCore/runtime/Structure.h

@@ -390 +390 @@
     JS_EXPORT_PRIVATE Structure(VM&, JSGlobalObject*, JSValue prototype, const TypeInfo&, const ClassInfo*, IndexingType, unsigned inlineCapacity);
     Structure(VM&);
-    Structure(VM&, const Structure*);
-
-    static Structure* create(VM&, const Structure*);
+    Structure(VM&, Structure*);
+
+    static Structure* create(VM&, Structure*);
     
     static Structure* addPropertyTransitionToExistingStructureImpl(Structure*, StringImpl* uid, unsigned attributes, JSCell* specificValue, PropertyOffset&);

trunk/Source/JavaScriptCore/runtime/StructureInlines.h

@@ -50 +50 @@
 }
 
-inline Structure* Structure::create(VM& vm, const Structure* structure)
+inline Structure* Structure::create(VM& vm, Structure* structure)
 {
     ASSERT(vm.structureStructure);