Add CODE_POINTER_ALIGN, use it in Page to align generated code.

src/objects.h

 // Copyright 2006-2009 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 2991 matching lines @@
   // Dispatched behavior.
   int CodeSize() { return SizeFor(body_size()); }
   inline void CodeIterateBody(ObjectVisitor* v);
 
   template<typename StaticVisitor>
   inline void CodeIterateBody();
 #ifdef DEBUG
   void CodePrint();
   void CodeVerify();
 #endif
-  // Code entry points are aligned to 32 bytes.
-  static const int kCodeAlignmentBits = 5;
-  static const int kCodeAlignment = 1 << kCodeAlignmentBits;
-  static const int kCodeAlignmentMask = kCodeAlignment - 1;
-
   // Layout description.
   static const int kInstructionSizeOffset = HeapObject::kHeaderSize;
   static const int kRelocationInfoOffset = kInstructionSizeOffset + kIntSize;
   static const int kFlagsOffset = kRelocationInfoOffset + kPointerSize;
   static const int kKindSpecificFlagsOffset  = kFlagsOffset + kIntSize;
   // Add padding to align the instruction start following right after
   // the Code object header.
   static const int kHeaderSize =
-      (kKindSpecificFlagsOffset + kIntSize + kCodeAlignmentMask) &
-          ~kCodeAlignmentMask;
+      CODE_POINTER_ALIGN(kKindSpecificFlagsOffset + kIntSize);
 
   // Byte offsets within kKindSpecificFlagsOffset.
   static const int kStubMajorKeyOffset = kKindSpecificFlagsOffset + 1;
 
   // Flags layout.
   static const int kFlagsICStateShift        = 0;
   static const int kFlagsICInLoopShift       = 3;
   static const int kFlagsTypeShift           = 4;
   static const int kFlagsKindShift           = 7;
   static const int kFlagsICHolderShift       = 11;
@@ skipping 2675 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_