Implement caching scheme for Date fields.

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 875 matching lines @@
   INLINE(bool IsTrue());
   INLINE(bool IsFalse());
   inline bool IsArgumentsMarker();
   inline bool NonFailureIsHeapObject();
 
   // Filler objects (fillers and free space objects).
   inline bool IsFiller();
 
   // Extract the number.
   inline double Number();
+  inline bool IsNaN();
 
   // Returns true if the object is of the correct type to be used as a
   // implementation of a JSObject's elements.
   inline bool HasValidElements();
 
   inline bool HasSpecificClassOf(String* name);
 
   MUST_USE_RESULT MaybeObject* ToObject();             // ECMA-262 9.9.
   Object* ToBoolean();                                 // ECMA-262 9.2.
 
@@ skipping 5120 matching lines @@
   DISALLOW_IMPLICIT_CONSTRUCTORS(JSValue);
 };
 
 
 // Representation for JS date objects.
 class JSDate: public JSObject {
  public:
   // If one component is NaN, all of them are, indicating a NaN time value.
   // [value]: the time value.
   DECL_ACCESSORS(value, Object)
+  // [local]: the offset for the local time value.
+  DECL_ACCESSORS(local, Object)
   // [year]: caches year. Either undefined, smi, or NaN.
   DECL_ACCESSORS(year, Object)
   // [month]: caches month. Either undefined, smi, or NaN.
   DECL_ACCESSORS(month, Object)
   // [day]: caches day. Either undefined, smi, or NaN.
   DECL_ACCESSORS(day, Object)
   // [hour]: caches hours. Either undefined, smi, or NaN.
   DECL_ACCESSORS(hour, Object)
   // [min]: caches minutes. Either undefined, smi, or NaN.
   DECL_ACCESSORS(min, Object)
   // [sec]: caches seconds. Either undefined, smi, or NaN.
   DECL_ACCESSORS(sec, Object)
-  // [ms]: caches milliseconds. Either undefined, smi, or NaN.
-  DECL_ACCESSORS(ms, Object)
+  // [weekday]: caches day of week. Either undefined, smi, or NaN.
+  DECL_ACCESSORS(weekday, Object)
 
   // Casting.
   static inline JSDate* cast(Object* obj);
 
   // Dispatched behavior.
 #ifdef OBJECT_PRINT
   inline void JSDatePrint() {
     JSDatePrint(stdout);
   }
   void JSDatePrint(FILE* out);
 #endif
 #ifdef DEBUG
   void JSDateVerify();
 #endif
 
   // Layout description.
   static const int kValueOffset = JSObject::kHeaderSize;
-  static const int kYearOffset = kValueOffset + kPointerSize;
+  static const int kLocalOffset = kValueOffset + kPointerSize;
+  static const int kYearOffset = kLocalOffset + kPointerSize;
   static const int kMonthOffset = kYearOffset + kPointerSize;
   static const int kDayOffset = kMonthOffset + kPointerSize;
   static const int kHourOffset = kDayOffset + kPointerSize;
   static const int kMinOffset = kHourOffset + kPointerSize;
   static const int kSecOffset = kMinOffset + kPointerSize;
-  static const int kMsOffset = kSecOffset + kPointerSize;
-  static const int kSize = kMsOffset + kPointerSize;
+  static const int kWeekdayOffset = kSecOffset + kPointerSize;
+  static const int kSize = kWeekdayOffset + kPointerSize;
 
   // Index of first field not requiring a write barrier.
-  static const int kFirstBarrierFree = 1;  // year
+  static const int kFirstBarrierFree = 2;  // year
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(JSDate);
 };
 
 
 // Representation of message objects used for error reporting through
 // the API. The messages are formatted in JavaScript so this object is
 // a real JavaScript object. The information used for formatting the
 // error messages are not directly accessible from JavaScript to
@@ skipping 2436 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_