return labels;
}

// Generate new unnamed labels for the expression.
// For example, if we have GenerateLabels(2, {'b', 'c', 'd'}) for "...xy"
// We will have "dcxy" for the ellipsis expression since it's rank 4,
// we will have dcbxy if it's rank 5.
std::string GenerateLabels(int count,
                           const llvm::SetVector<char>& available_labels) {
  std::string new_labels(count, 0);