namespace {
  // Hello - The first implementation, without getAnalysisUsage.
  struct Hello : public ModulePass {
    static char ID; // Pass identification, replacement for typeid
    Hello() : ModulePass(ID) {}

    bool runOnModule(Module &M) override {
      if (auto main = M.getFunction("main")) {
        ValueToValueMapTy vmap;
        auto newF = CloneFunction(main, vmap, true);
        M.getFunctionList().push_back(newF);
        IRBuilder<> IRB(&*main->getEntryBlock().getFirstInsertionPt());
        IRB.CreateCall(newF, {&main->getArgumentList().front(), &main->getArgumentList().back()});
      }
      return true;
    }
  };
}