functionality of the old tgba_tba_proxy.
* src/tgba/tgbatba.cc (tgba_tba_proxy_succ_iterator,
tgba_tba_proxy): Rewrite to produce TBA with at most N copies of
each state, skipping the `bddtrue' stage now used only in
tgba_sba_proxy. Doing so removes approximately 6% of states in
the degeneralized tests of spotlbtt.test.
(tgba_sba_proxy): Implement it.
* src/tgbaalgos/neverclaim.hh, src/tgbaalgos/neverclaim.cc: Adjust
to take a tgba_sba_proxy.
* src/tgbatest/ltl2tgba.cc: Add option -DS and adjust call to
never_claim_reachable().
arguments.
* src/tgbaalgos/neverclaim.cc (never_claim_bfs::state_is_accepting):
New method.
(never_claim_bfs::get_state_label, never_claim_bfs::process_state):
Use it.
Convert a formula into a string parsable by Spin.
* src/tgbaalgos/neverclaim.hh, src/tgbaalgos/neverclaim.cc: New files.
Print the never claim in Spin format of a degeneralized TGBA.
* src/tgbaalgos/Makefile.am: Add them.
* src/tgbatest/ltl2tgba.cc: Add the option -N which outputs the
never claim in Spin format of a degeneralized TGBA.
* src/tgbatest/ltl2neverclaim.test: New file.
* src/tgbatest/Makefile.am: Add it.
