Allow smis for singleton types

src/heap.cc

 // Copyright 2012 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 2683 matching lines @@
   { MaybeObject* maybe_result = AllocateRawCell();
     if (!maybe_result->ToObject(&result)) return maybe_result;
   }
   HeapObject::cast(result)->set_map_no_write_barrier(
       global_property_cell_map());
   JSGlobalPropertyCell::cast(result)->set_value(value);
   return result;
 }
 
 
+MaybeObject* Heap::AllocateBox(Object* value, PretenureFlag pretenure) {
+  Box* result;
+  MaybeObject* maybe_result = AllocateStruct(BOX_TYPE);
+  if (!maybe_result->To(&result)) return maybe_result;
+  result->set_value(value);
+  return result;
+}
+
+
 MaybeObject* Heap::CreateOddball(const char* to_string,
                                  Object* to_number,
                                  byte kind) {
   Object* result;
   { MaybeObject* maybe_result = Allocate(oddball_map(), OLD_POINTER_SPACE);
     if (!maybe_result->ToObject(&result)) return maybe_result;
   }
   return Oddball::cast(result)->Initialize(to_string, to_number, kind);
 }
 
@@ skipping 5182 matching lines @@
   if (FLAG_parallel_recompilation) {
     heap_->relocation_mutex_->Lock();
 #ifdef DEBUG
     heap_->relocation_mutex_locked_by_optimizer_thread_ =
         heap_->isolate()->optimizing_compiler_thread()->IsOptimizerThread();
 #endif  // DEBUG
   }
 }
 
 } }  // namespace v8::internal