private static ReadOnlyCollection <PrimitiveType> GetPrimitiveCommonSuperTypes(
PrimitiveType primitiveType1,
PrimitiveType primitiveType2)
{
TypeSemantics.ComputeCommonTypeClosure();
return(TypeSemantics._commonTypeClosure[(int)primitiveType1.PrimitiveTypeKind, (int)primitiveType2.PrimitiveTypeKind]);
}