@NotNull
  private static Multimap<FqName, Pair<FunctionDescriptor, PsiMethod>>
      getSuperclassToFunctionsMultimap(
          @NotNull PsiMethodWrapper method,
          @NotNull BindingContext bindingContext,
          @NotNull ClassDescriptor containingClass) {
    Multimap<FqName, Pair<FunctionDescriptor, PsiMethod>> result = HashMultimap.create();

    Name functionName = Name.identifier(method.getName());
    int parameterCount = method.getParameters().size();

    for (JetType supertype : TypeUtils.getAllSupertypes(containingClass.getDefaultType())) {
      ClassifierDescriptor klass = supertype.getConstructor().getDeclarationDescriptor();
      assert klass != null;
      FqName fqName = DescriptorUtils.getFQName(klass).toSafe();

      for (FunctionDescriptor fun :
          klass.getDefaultType().getMemberScope().getFunctions(functionName)) {
        if (fun.getKind().isReal() && fun.getValueParameters().size() == parameterCount) {
          PsiElement declaration = BindingContextUtils.descriptorToDeclaration(bindingContext, fun);
          if (declaration instanceof PsiMethod) {
            result.put(fqName, Pair.create(fun, (PsiMethod) declaration));
          } // else declaration is null or JetNamedFunction: both cases are processed later
        }
      }
    }
    return result;
  }
 private static Map<ClassDescriptor, JetType> getSuperclassToSupertypeMap(
     ClassDescriptor containingClass) {
   Map<ClassDescriptor, JetType> superclassToSupertype = Maps.newHashMap();
   for (JetType supertype : TypeUtils.getAllSupertypes(containingClass.getDefaultType())) {
     ClassifierDescriptor superclass = supertype.getConstructor().getDeclarationDescriptor();
     assert superclass instanceof ClassDescriptor;
     superclassToSupertype.put((ClassDescriptor) superclass, supertype);
   }
   return superclassToSupertype;
 }