private static void makeMainLoop(CFGBuilder builder, Step firstStep, PsiType inType) {
    builder.doWhileUnknown()
           .assign(builder.createTempVariable(inType), DfTypes.typedObject(inType, DfaPsiUtil.getTypeNullability(inType)))
           .chain(firstStep::iteration).end();
  }
private static void makeMainLoop(CFGBuilder builder, Step firstStep, PsiType inType)