Allocate as many object-literal properties as possible inobject....

src/objects.h

Index: src/objects.h
===================================================================
--- src/objects.h	(revision 1049)
+++ src/objects.h	(working copy)
@@ -166,9 +166,20 @@
   uint32_t value_;
 };
 
+
 // Setter that skips the write barrier if mode is SKIP_WRITE_BARRIER.
 enum WriteBarrierMode { SKIP_WRITE_BARRIER, UPDATE_WRITE_BARRIER };
 
+
+// PropertyNormalizationMode is used to specify wheter or not to
+// keep inobject properties when normalizing properties of a
+// JSObject.
+enum PropertyNormalizationMode {
+  CLEAR_INOBJECT_PROPERTIES,
+  KEEP_INOBJECT_PROPERTIES
+};
+
+
 // All Maps have a field instance_type containing a InstanceType.
 // It describes the type of the instances.
 //
@@ -560,9 +571,9 @@
   inline void set_##name(bool value);  \
 
 
-#define DECL_ACCESSORS(name, type)    \
-  inline type* name();                \
-  inline void set_##name(type* value, \
+#define DECL_ACCESSORS(name, type)                                      \
+  inline type* name();                                                  \
+  inline void set_##name(type* value,                                   \
                          WriteBarrierMode mode = UPDATE_WRITE_BARRIER); \
 
 
@@ -1357,7 +1368,7 @@
 
   // Convert the object to use the canonical dictionary
   // representation.
-  Object* NormalizeProperties();
+  Object* NormalizeProperties(PropertyNormalizationMode mode);
   Object* NormalizeElements();
 
   // Transform slow named properties to fast variants.
@@ -2293,7 +2304,7 @@
 //  - How to iterate over an object (for garbage collection)
 class Map: public HeapObject {
  public:
-  // instance size.
+  // Instance size.
   inline int instance_size();
   inline void set_instance_size(int value);
 
@@ -2301,16 +2312,16 @@
   inline int inobject_properties();
   inline void set_inobject_properties(int value);
 
-  // instance type.
+  // Instance type.
   inline InstanceType instance_type();
   inline void set_instance_type(InstanceType value);
 
-  // tells how many unused property fields are available in the instance.
-  // (only used for JSObject in fast mode).
+  // Tells how many unused property fields are available in the
+  // instance (only used for JSObject in fast mode).
   inline int unused_property_fields();
   inline void set_unused_property_fields(int value);
 
-  // bit field.
+  // Bit field.
   inline byte bit_field();
   inline void set_bit_field(byte value);
 
@@ -2463,7 +2474,6 @@
   static const int kInObjectPropertiesOffset = kInstanceSizesOffset + 1;
   // The bytes at positions 2 and 3 are not in use at the moment.
 
-
   // Byte offsets within kInstanceAttributesOffset attributes.
   static const int kInstanceTypeOffset = kInstanceAttributesOffset + 0;
   static const int kUnusedPropertyFieldsOffset = kInstanceAttributesOffset + 1;