Add kHeaderSize constant to SeqString.

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 6109 matching lines @@
   DISALLOW_IMPLICIT_CONSTRUCTORS(String);
 };
 
 
 // The SeqString abstract class captures sequential string values.
 class SeqString: public String {
  public:
   // Casting.
   static inline SeqString* cast(Object* obj);
 
+  // Layout description.
+  static const int kHeaderSize = String::kSize;
+  static const int kAlignedSize = POINTER_SIZE_ALIGN(kHeaderSize);

[Lasse Reichstein, 2011/09/20 08:42:01]

Do we ever use kAlignedSize any more?
Since we made the string length a Smi, it's always the same as kHeaderSize (even
on x64, where previously it was kIntSize less), so we could remove it now.

[Michael Starzinger, 2011/09/20 16:07:39]

Done.

+
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(SeqString);
 };
 
 
 // The AsciiString class captures sequential ascii string objects.
 // Each character in the AsciiString is an ascii character.
 class SeqAsciiString: public SeqString {
  public:
   static const bool kHasAsciiEncoding = true;
@@ skipping 13 matching lines @@
   // Garbage collection support.  This method is called by the
   // garbage collector to compute the actual size of an AsciiString
   // instance.
   inline int SeqAsciiStringSize(InstanceType instance_type);
 
   // Computes the size for an AsciiString instance of a given length.
   static int SizeFor(int length) {
     return OBJECT_POINTER_ALIGN(kHeaderSize + length * kCharSize);
   }
 
-  // Layout description.
-  static const int kHeaderSize = String::kSize;
-  static const int kAlignedSize = POINTER_SIZE_ALIGN(kHeaderSize);
-
   // Maximal memory usage for a single sequential ASCII string.
   static const int kMaxSize = 512 * MB - 1;
   // Maximal length of a single sequential ASCII string.
   // Q.v. String::kMaxLength which is the maximal size of concatenated strings.
   static const int kMaxLength = (kMaxSize - kHeaderSize);
 
   // Support for StringInputBuffer.
   inline void SeqAsciiStringReadBlockIntoBuffer(ReadBlockBuffer* buffer,
                                                 unsigned* offset,
                                                 unsigned chars);
@@ skipping 30 matching lines @@
   // Garbage collection support.  This method is called by the
   // garbage collector to compute the actual size of a TwoByteString
   // instance.
   inline int SeqTwoByteStringSize(InstanceType instance_type);
 
   // Computes the size for a TwoByteString instance of a given length.
   static int SizeFor(int length) {
     return OBJECT_POINTER_ALIGN(kHeaderSize + length * kShortSize);
   }
 
-  // Layout description.
-  static const int kHeaderSize = String::kSize;
-  static const int kAlignedSize = POINTER_SIZE_ALIGN(kHeaderSize);
-
   // Maximal memory usage for a single sequential two-byte string.
   static const int kMaxSize = 512 * MB - 1;
   // Maximal length of a single sequential two-byte string.
   // Q.v. String::kMaxLength which is the maximal size of concatenated strings.
   static const int kMaxLength = (kMaxSize - kHeaderSize) / sizeof(uint16_t);
 
   // Support for StringInputBuffer.
   inline void SeqTwoByteStringReadBlockIntoBuffer(ReadBlockBuffer* buffer,
                                                   unsigned* offset_ptr,
                                                   unsigned chars);
@@ skipping 1162 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_