code: private boolean isPredicateKnown_(int predicate) {
          assert(m_scl.charAt(predicate) != '*');
  
          if (m_matrix[predicate] == -2)
              return false;
  
          if (m_matrix[predicate] == -1)
          {
              m_perform_predicates[predicate] = false;
              m_predicate_count--;
              return true;
          }
  
          if (m_scl.charAt(predicate) != 'T' && m_scl.charAt(predicate) != 'F')
          {
              if (m_matrix[predicate] < m_max_dim[predicate])
              {
                  return false;
              }
              else
              {
                  m_perform_predicates[predicate] = false;
                  m_predicate_count--;
                  return true;
              }
          }
          else
          {
              m_perform_predicates[predicate] = false;
              m_predicate_count--;
              return true;
          }
  	}
docs: Checks whether the predicate is known.