bool IsAlpha(char c) {
  return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z');
}

bool IsAlphaNum(char c) { return IsAlpha(c) || (c >= '0' && c <= '9'); }

// Convert an XLA type into a C++ type.
Status XLATypeToCpp(xla::PrimitiveType type, string* str) {
  switch (type) {
    case xla::PRED:
      *str = "bool";
      break;
    case xla::S8:
      *str = "tensorflow::int8";
      break;
    case xla::S16: