}

 private:
  // Returns a cache key proto that identifies an entry in the compilation
  // cache.
  XlaSerializedCacheKey BuildSerializedCacheKey(
      uint64 signature_hash, const xla::HloModuleProto& hlo_module) const;

  XlaSerializedCacheKey BuildSerializedCacheKey(
      uint64 signature_hash, const xla::HloModuleProto& hlo_module,
      bool compiled_using_pjrt) const;