Use Heap::CreateFillerArrayAt to create a filler instead of copied code.

src/builtins.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 330 matching lines @@
   STATIC_ASSERT(FixedArray::kLengthOffset == kPointerSize);
   STATIC_ASSERT(FixedArray::kHeaderSize == 2 * kPointerSize);
 
   Object** former_start = HeapObject::RawField(elms, 0);
 
   const int len = elms->length();
 
   // Technically in new space this write might be omitted (except for
   // debug mode which iterates through the heap), but to play safer
   // we still do it.
-  if (to_trim == 1) {
-    former_start[0] = Heap::raw_unchecked_one_pointer_filler_map();
-  } else if (to_trim == 2) {
-    former_start[0] = Heap::raw_unchecked_two_pointer_filler_map();
-  } else {
-    former_start[0] = Heap::raw_unchecked_byte_array_map();
-    ByteArray* as_byte_array = reinterpret_cast<ByteArray*>(elms);
-    as_byte_array->set_length(ByteArray::LengthFor(to_trim * kPointerSize));
-  }
+  Heap::CreateFillerObjectAt(elms->address(), to_trim * kPointerSize);
 
   former_start[to_trim] = Heap::fixed_array_map();
   former_start[to_trim + 1] = reinterpret_cast<Object*>(len - to_trim);
 
   ASSERT_EQ(elms->address() + to_trim * kPointerSize,
             (elms + to_trim * kPointerSize)->address());
   return elms + to_trim * kPointerSize;
 }
 
 
@@ skipping 1170 matching lines @@
       if (entry->contains(pc)) {
         return names_[i];
       }
     }
   }
   return NULL;
 }
 
 
 } }  // namespace v8::internal