Move the initial code space to be before the young space instead of after it....

src/heap.cc

 // 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 2443 matching lines @@
   if (!MemoryAllocator::Setup(MaxCapacity())) return false;
   void* chunk
       = MemoryAllocator::ReserveInitialChunk(2 * young_generation_size_);
   if (chunk == NULL) return false;
 
   // Put the initial chunk of the old space at the start of the initial
   // chunk, then the two new space semispaces, then the initial chunk of
   // code space.  Align the pair of semispaces to their size, which must be
   // a power of 2.
   ASSERT(IsPowerOf2(young_generation_size_));
-  Address old_space_start = reinterpret_cast<Address>(chunk);
-  Address new_space_start = RoundUp(old_space_start, young_generation_size_);
-  Address code_space_start = new_space_start + young_generation_size_;
-  int old_space_size = new_space_start - old_space_start;
-  int code_space_size = young_generation_size_ - old_space_size;
+  Address code_space_start = reinterpret_cast<Address>(chunk);
+  Address new_space_start = RoundUp(code_space_start, young_generation_size_);
+  Address old_space_start = new_space_start + young_generation_size_;
+  int code_space_size = new_space_start - code_space_start;
+  int old_space_size = young_generation_size_ - code_space_size;
 
   // Initialize new space.
   new_space_ = new NewSpace(initial_semispace_size_,
                             semispace_size_,
                             NEW_SPACE);
   if (new_space_ == NULL) return false;
   if (!new_space_->Setup(new_space_start, young_generation_size_)) return false;
 
   // Initialize old space, set the maximum capacity to the old generation
   // size. It will not contain code.
@@ skipping 556 matching lines @@
       return "Scavenge";
     case MARK_COMPACTOR:
       return MarkCompactCollector::HasCompacted() ? "Mark-compact"
                                                   : "Mark-sweep";
   }
   return "Unknown GC";
 }
 
 
 } }  // namespace v8::internal