Use Representation::Integer32() for smi types on 32-bit-tagged systems.

src/types.cc

 // Copyright 2013 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 550 matching lines @@
           Convert<OtherType>(OtherType::UnionGet(unioned, i), region));
     }
     return Config::from_union(new_unioned);
   }
 }
 
 
 // TODO(rossberg): this does not belong here.
 Representation Representation::FromType(Type* type) {
   if (type->Is(Type::None())) return Representation::None();
-  if (type->Is(Type::Smi())) return Representation::Smi();
+  if (type->Is(Type::Smi())) return SmiValuesAre31Bits()
+      ? Representation::Smi() : Representation::Integer32();
   if (type->Is(Type::Signed32())) return Representation::Integer32();
   if (type->Is(Type::Number())) return Representation::Double();
   return Representation::Tagged();
 }
 
 
 #ifdef OBJECT_PRINT
 template<class Config>
 void TypeImpl<Config>::TypePrint() {
   TypePrint(stdout);
@@ skipping 65 matching lines @@
 
 template TypeImpl<ZoneTypeConfig>::TypeHandle
   TypeImpl<ZoneTypeConfig>::Convert<HeapType>(
     TypeImpl<HeapTypeConfig>::TypeHandle, TypeImpl<ZoneTypeConfig>::Region*);
 template TypeImpl<HeapTypeConfig>::TypeHandle
   TypeImpl<HeapTypeConfig>::Convert<Type>(
     TypeImpl<ZoneTypeConfig>::TypeHandle, TypeImpl<HeapTypeConfig>::Region*);
 
 
 } }  // namespace v8::internal