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

src/spaces.h

 // Copyright 2006-2008 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 225 matching lines @@
 
   // Page size in bytes.  This must be a multiple of the OS page size.
   static const int kPageSize = 1 << kPageSizeBits;
 
   // Page size mask.
   static const intptr_t kPageAlignmentMask = (1 << kPageSizeBits) - 1;
 
   static const int kPageHeaderSize = kPointerSize + kPointerSize + kIntSize +
     kIntSize + kPointerSize;
 
-  // The start offset of the object area in a page.
-  static const int kObjectStartOffset = MAP_POINTER_ALIGN(kPageHeaderSize);
+  // The start offset of the object area in a page. Aligned to both maps and
+  // code alignment to be suitabel for both.

[Vitaly Repeshko, 2010/09/24 15:45:38]

Typo: "suitable". 

+  static const int kObjectStartOffset =
+      CODE_POINTER_ALIGN(MAP_POINTER_ALIGN(kPageHeaderSize));
 
   // Object area size in bytes.
   static const int kObjectAreaSize = kPageSize - kObjectStartOffset;
 
   // Maximum object size that fits in a page.
   static const int kMaxHeapObjectSize = kObjectAreaSize;
 
   static const int kDirtyFlagOffset = 2 * kPointerSize;
   static const int kRegionSizeLog2 = 8;
   static const int kRegionSize = 1 << kRegionSizeLog2;
@@ skipping 1992 matching lines @@
 
  private:
   LargeObjectChunk* current_;
   HeapObjectCallback size_func_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_SPACES_H_