Function DebugString

be/src/exprs/conditional-functions.h:80–82

  virtual Status GetCodegendComputeFnImpl(LlvmCodeGen* codegen, llvm::Function** fn)
      override WARN_UNUSED_RESULT;
  virtual std::string DebugString() const override {
    return ScalarExpr::DebugString("IsNullExpr");
  }

 protected:
  friend class ScalarExpr;