  E-generalization computes common generalizations of given ground terms w.r.t.
a given equational background theory E. In 2005 [arXiv:1403.8118], we had
presented a computation approach based on standard regular tree grammar
algorithms, and a Prolog prototype implementation. In this report, we present
algorithmic improvements, prove them correct and complete, and give some
details of an efficiency-oriented implementation in C that allows us to handle
problems larger by several orders of magnitude.
