Use platform specific stubs for vector-based Load/KeyedLoad.

src/objects.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_OBJECTS_H_
 #define V8_OBJECTS_H_
 
 #include <iosfwd>
 
 #include "src/allocation.h"
@@ skipping 8764 matching lines @@
   static inline bool IsHashFieldComputed(uint32_t field);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(Name);
 };
 
 
 // ES6 symbols.
 class Symbol: public Name {
  public:
-  // [name]: the print name of a symbol, or undefined if none.
+  DECL_ACCESSORS(flags, Smi)
+
+  // [name]: the print name of a symbol, or undefined if none
   DECL_ACCESSORS(name, Object)
 
-  DECL_ACCESSORS(flags, Smi)
-
   // [is_private]: whether this is a private symbol.
   DECL_BOOLEAN_ACCESSORS(is_private)
 
   // [is_own]: whether this is an own symbol, that is, only used to designate
   // own properties of objects.
   DECL_BOOLEAN_ACCESSORS(is_own)
 
   DECLARE_CAST(Symbol)
 
   // Dispatched behavior.
   DECLARE_PRINTER(Symbol)
   DECLARE_VERIFIER(Symbol)
 
   // Layout description.
-  static const int kNameOffset = Name::kSize;
-  static const int kFlagsOffset = kNameOffset + kPointerSize;
-  static const int kSize = kFlagsOffset + kPointerSize;
+  static const int kFlagsOffset = Name::kSize;

[Toon Verwaest, 2015/03/11 17:55:02]

Is this still necessary?
[At this point haven't looked at platform specific files yet, but I seem to
recall that this idea was discarded]

[mvstanton, 2015/03/12 17:05:34]

Yes, I still want to do something in here but I'll move it out to a future CL.

+  static const int kNameOffset = kFlagsOffset + kPointerSize;
+  static const int kSize = kNameOffset + kPointerSize;
 
-  typedef FixedBodyDescriptor<kNameOffset, kFlagsOffset, kSize> BodyDescriptor;
+  typedef FixedBodyDescriptor<kFlagsOffset, kNameOffset + kPointerSize, kSize>
+      BodyDescriptor;
 
   void SymbolShortPrint(std::ostream& os);
 
  private:
   static const int kPrivateBit = 0;
   static const int kOwnBit = 1;
 
   const char* PrivateSymbolToName() const;
 
 #if TRACE_MAPS
@@ skipping 2164 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_