Support Smi->Double->HeapObject transitions in constructed Arrays.

src/objects.h

 // Copyright 2011 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 1304 matching lines @@
   static const int kExponentBias = 1023;
   static const int kExponentShift = 20;
   static const int kMantissaBitsInTopWord = 20;
   static const int kNonMantissaBitsInTopWord = 12;
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(HeapNumber);
 };
 
 
+enum EnsureElementsMode {
+  DONT_ALLOW_DOUBLE_ELEMENTS,
+  ALLOW_COPIED_DOUBLE_ELEMENTS,
+  ALLOW_CONVERTED_DOUBLE_ELEMENTS
+};
+
+
 // JSReceiver includes types on which properties can be defined, i.e.,
 // JSObject and JSProxy.
 class JSReceiver: public HeapObject {
  public:
   enum DeleteMode {
     NORMAL_DELETION,
     STRICT_DELETION,
     FORCE_DELETION
   };
 
@@ skipping 273 matching lines @@
   bool HasHiddenProperties();
 
   MUST_USE_RESULT MaybeObject* GetIdentityHash(CreationFlag flag);
   MUST_USE_RESULT MaybeObject* SetIdentityHash(Object* hash, CreationFlag flag);
 
   MUST_USE_RESULT MaybeObject* DeleteProperty(String* name, DeleteMode mode);
   MUST_USE_RESULT MaybeObject* DeleteElement(uint32_t index, DeleteMode mode);
 
   inline void ValidateSmiOnlyElements();
 
-  // Makes sure that this object can contain non-smi Object as elements.
-  inline MaybeObject* EnsureCanContainNonSmiElements();
+  // Makes sure that this object can contain HeapObject as elements.
+  inline MaybeObject* EnsureCanContainHeapObjectElements();
 
   // Makes sure that this object can contain the specified elements.
   inline MaybeObject* EnsureCanContainElements(Object** elements,
-                                               uint32_t count);
-  inline MaybeObject* EnsureCanContainElements(FixedArray* elements);
+                                               uint32_t count,
+                                               EnsureElementsMode mode);
+  inline MaybeObject* EnsureCanContainElements(FixedArrayBase* elements,
+                                               EnsureElementsMode mode);
   MaybeObject* EnsureCanContainElements(Arguments* arguments,
                                         uint32_t first_arg,
-                                        uint32_t arg_count);
+                                        uint32_t arg_count,
+                                        EnsureElementsMode mode);
 
   // Do we want to keep the elements in fast case when increasing the
   // capacity?
   bool ShouldConvertToSlowElements(int new_capacity);
   // Returns true if the backing storage for the slow-case elements of
   // this object takes up nearly as much space as a fast-case backing
   // storage would.  In that case the JSObject should have fast
   // elements.
   bool ShouldConvertToFastElements();
   // Returns true if the elements of JSObject contains only values that can be
@@ skipping 479 matching lines @@
 
   // Setters with less debug checks for the GC to use.
   inline void set_unchecked(int index, Smi* value);
   inline void set_null_unchecked(Heap* heap, int index);
   inline void set_unchecked(Heap* heap, int index, Object* value,
                             WriteBarrierMode mode);
 
   // Gives access to raw memory which stores the array's data.
   inline Object** data_start();
 
+  inline Object** GetFirstElementAddress();
+  inline bool ContainsOnlySmisOrHoles();
+
   // Copy operations.
   MUST_USE_RESULT inline MaybeObject* Copy();
   MUST_USE_RESULT MaybeObject* CopySize(int new_length);
 
   // Add the elements of a JSArray to this FixedArray.
   MUST_USE_RESULT MaybeObject* AddKeysFromJSArray(JSArray* array);
 
   // Compute the union of this and other.
   MUST_USE_RESULT MaybeObject* UnionOfKeys(FixedArray* other);
 
@@ skipping 5247 matching lines @@
 
   MUST_USE_RESULT MaybeObject* JSArrayUpdateLengthFromIndex(uint32_t index,
                                                             Object* value);
 
   // Initialize the array with the given capacity. The function may
   // fail due to out-of-memory situations, but only if the requested
   // capacity is non-zero.
   MUST_USE_RESULT MaybeObject* Initialize(int capacity);
 
   // Set the content of the array to the content of storage.
-  inline MaybeObject* SetContent(FixedArray* storage);
+  inline MaybeObject* SetContent(FixedArrayBase* storage);
 
   // Casting.
   static inline JSArray* cast(Object* obj);
 
   // Uses handles.  Ensures that the fixed array backing the JSArray has at
   // least the stated size.
   inline void EnsureSize(int minimum_size_of_backing_fixed_array);
 
   // Dispatched behavior.
 #ifdef OBJECT_PRINT
@@ skipping 588 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_