Split NumberDictionary into a randomly seeded and an unseeded

src/objects.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1467 matching lines @@
   inline bool HasExternalByteElements();
   inline bool HasExternalUnsignedByteElements();
   inline bool HasExternalShortElements();
   inline bool HasExternalUnsignedShortElements();
   inline bool HasExternalIntElements();
   inline bool HasExternalUnsignedIntElements();
   inline bool HasExternalFloatElements();
   inline bool HasExternalDoubleElements();
   bool HasFastArgumentsElements();
   bool HasDictionaryArgumentsElements();
-  inline NumberDictionary* element_dictionary();  // Gets slow elements.
+  inline SeededNumberDictionary* element_dictionary();  // Gets slow elements.
 
   inline void set_map_and_elements(
       Map* map,
       FixedArrayBase* value,
       WriteBarrierMode mode = UPDATE_WRITE_BARRIER);
 
   // Requires: HasFastElements().
   MUST_USE_RESULT inline MaybeObject* EnsureWritableFastElements();
 
   // Collects elements starting at index 0.
@@ skipping 402 matching lines @@
   // added this number can be indicated to have the backing store allocated to
   // an initial capacity for holding these properties.
   static void NormalizeProperties(Handle<JSObject> object,
                                   PropertyNormalizationMode mode,
                                   int expected_additional_properties);
 
   MUST_USE_RESULT MaybeObject* NormalizeProperties(
       PropertyNormalizationMode mode,
       int expected_additional_properties);
 
-  // Convert and update the elements backing store to be a NumberDictionary
-  // dictionary.  Returns the backing after conversion.
-  static Handle<NumberDictionary> NormalizeElements(Handle<JSObject> object);
+  // Convert and update the elements backing store to be a
+  // SeededNumberDictionary dictionary.  Returns the backing after conversion.
+  static Handle<SeededNumberDictionary> NormalizeElements(
+      Handle<JSObject> object);
 
   MUST_USE_RESULT MaybeObject* NormalizeElements();
 
   static void UpdateMapCodeCache(Handle<JSObject> object,
                                  Handle<String> name,
                                  Handle<Code> code);
 
   MUST_USE_RESULT MaybeObject* UpdateMapCodeCache(String* name, Code* code);
 
   // Transform slow named properties to fast variants.
@@ skipping 346 matching lines @@
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(FixedArray);
 };
 
 
 // FixedDoubleArray describes fixed-sized arrays with element type double.
 class FixedDoubleArray: public FixedArrayBase {
  public:
   inline void Initialize(FixedArray* from);
   inline void Initialize(FixedDoubleArray* from);
-  inline void Initialize(NumberDictionary* from);
+  inline void Initialize(SeededNumberDictionary* from);
 
   // Setter and getter for elements.
   inline double get_scalar(int index);
   inline MaybeObject* get(int index);
   inline void set(int index, double value);
   inline void set_the_hole(int index);
 
   // Checking for the hole.
   inline bool is_the_hole(int index);
 
@@ skipping 740 matching lines @@
       int unused_property_fields);
 
   // Find entry for key, otherwise return kNotFound. Optimized version of
   // HashTable::FindEntry.
   int FindEntry(String* key);
 };
 
 
 class NumberDictionaryShape : public BaseShape<uint32_t> {
  public:
-  static const bool UsesSeed = true;
-
   static inline bool IsMatch(uint32_t key, Object* other);
-  static inline uint32_t Hash(uint32_t key);
-  static inline uint32_t SeededHash(uint32_t key, uint32_t seed);
-  static inline uint32_t HashForObject(uint32_t key, Object* object);
-  static inline uint32_t SeededHashForObject(uint32_t key,
-                                             uint32_t seed,
-                                             Object* object);
   MUST_USE_RESULT static inline MaybeObject* AsObject(uint32_t key);
-  static const int kPrefixSize = 2;
   static const int kEntrySize = 3;
   static const bool kIsEnumerable = false;
 };
 
 
-class NumberDictionary: public Dictionary<NumberDictionaryShape, uint32_t> {
+class SeededNumberDictionaryShape : public NumberDictionaryShape {
  public:
-  static NumberDictionary* cast(Object* obj) {
+  static const bool UsesSeed = true;
+  static const int kPrefixSize = 2;
+
+  static inline uint32_t SeededHash(uint32_t key, uint32_t seed);
+  static inline uint32_t SeededHashForObject(uint32_t key,
+                                             uint32_t seed,
+                                             Object* object);
+};
+
+
+class UnseededNumberDictionaryShape : public NumberDictionaryShape {
+ public:
+  static const int kPrefixSize = 0;
+
+  static inline uint32_t Hash(uint32_t key);
+  static inline uint32_t HashForObject(uint32_t key, Object* object);
+};
+
+
+class SeededNumberDictionary
+    : public Dictionary<SeededNumberDictionaryShape, uint32_t> {
+ public:
+  static SeededNumberDictionary* cast(Object* obj) {
     ASSERT(obj->IsDictionary());
-    return reinterpret_cast<NumberDictionary*>(obj);
+    return reinterpret_cast<SeededNumberDictionary*>(obj);
   }
 
   // Type specific at put (default NONE attributes is used when adding).
   MUST_USE_RESULT MaybeObject* AtNumberPut(uint32_t key, Object* value);
   MUST_USE_RESULT MaybeObject* AddNumberEntry(uint32_t key,
                                               Object* value,
                                               PropertyDetails details);
 
   // Set an existing entry or add a new one if needed.
   // Return the updated dictionary.
-  MUST_USE_RESULT static Handle<NumberDictionary> Set(
-      Handle<NumberDictionary> dictionary,
+  MUST_USE_RESULT static Handle<SeededNumberDictionary> Set(
+      Handle<SeededNumberDictionary> dictionary,
       uint32_t index,
       Handle<Object> value,
       PropertyDetails details);
 
   MUST_USE_RESULT MaybeObject* Set(uint32_t key,
                                    Object* value,
                                    PropertyDetails details);
 
   void UpdateMaxNumberKey(uint32_t key);
 
@@ skipping 10 matching lines @@
   // requires_slow_elements returns false.
   inline uint32_t max_number_key();
 
   // Bit masks.
   static const int kRequiresSlowElementsMask = 1;
   static const int kRequiresSlowElementsTagSize = 1;
   static const uint32_t kRequiresSlowElementsLimit = (1 << 29) - 1;
 };
 
 
+class UnseededNumberDictionary
+    : public Dictionary<UnseededNumberDictionaryShape, uint32_t> {
+ public:
+  static UnseededNumberDictionary* cast(Object* obj) {
+    ASSERT(obj->IsDictionary());
+    return reinterpret_cast<UnseededNumberDictionary*>(obj);
+  }
+
+  // Type specific at put (default NONE attributes is used when adding).
+  MUST_USE_RESULT MaybeObject* AtNumberPut(uint32_t key, Object* value);
+  MUST_USE_RESULT MaybeObject* AddNumberEntry(uint32_t key, Object* value);
+
+  // Set an existing entry or add a new one if needed.
+  // Return the updated dictionary.
+  MUST_USE_RESULT static Handle<UnseededNumberDictionary> Set(
+      Handle<UnseededNumberDictionary> dictionary,
+      uint32_t index,
+      Handle<Object> value);
+
+  MUST_USE_RESULT MaybeObject* Set(uint32_t key, Object* value);
+};
+
+
 template <int entrysize>
 class ObjectHashTableShape : public BaseShape<Object*> {
  public:
   static inline bool IsMatch(Object* key, Object* other);
   static inline uint32_t Hash(Object* key);
   static inline uint32_t HashForObject(Object* key, Object* object);
   MUST_USE_RESULT static inline MaybeObject* AsObject(Object* key);
   static const int kPrefixSize = 0;
   static const int kEntrySize = entrysize;
 };
@@ skipping 5040 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_