* src/eltlparse/Makefile.am, src/ltlvisit/randomltl.cc,
src/ltlvisit/simplify.cc, src/ltlvisit/snf.cc, src/ltlvisit/snf.hh:
Fix GPL to version 2 or later.
Doing so will release all BDD variables used by automata created for
syntactic implication. This way the main translation will create
acceptance variables again in a more natural order, which will help
the degeneralization (until we get a better degeneralization).
* src/ltlvisit/contain.cc, src/ltlvisit/contain.hh
(language_containment_checker::clear): New method to clear the
containment cache.
* src/ltlvisit/simplify.cc, src/ltlvisit/simplify.hh
(clear_as_bdd_cache): Also call language_containment_checker::clear.
Syntactic implication checks may use as_bdd() to compare Boolean
formulae. By doing so, they register Boolean variables in an order
that is usially detrimental to the LTL translator. The new,
clear_as_bdd_cache() function offers a mean to unregister these
variables, so that the LTL translator will register them again in the
a more natural way.
* src/ltlvisit/simplify.hh, src/ltlvisit/simplify.cc
(clear_as_bdd_cache): New function.
* src/tgbatest/ltl2tgba.cc, wrap/python/ajax/spot.in: Call it.
* src/ltlvisit/simplify.cc
(ltl_simplifier_cache::syntactic_implication): If the lhs and rhs are
literals that are not equal, return false immediately.
We need a marked version of !{r} to perform breakpoint unroling.
* src/ltlast/unop.cc, src/ltlast/unop.hh: Declare a NegClosureMarked
operator.
* src/ltlvisit/mark.hh, src/ltlvisit/mark.cc,
src/tgbaalgos/ltl2tgba_fm.cc: Adjust to deal with NegClosureMarked
and NegClosure as apropriate.
* src/ltlvisit/simplify.cc, src/ltlvisit/tostring.cc,
src/ltlvisit/tunabbrev.cc, src/tgbaalgos/eltl2tgba_lacim.cc,
src/tgbaalgos/ltl2taa.cc, src/tgbaalgos/ltl2tgba_lacim.cc,
src/tgba/formula2bdd.cc: Deal with NegClosureMarked in the same way as
we deal with NegClosure.
* src/tgbatest/ltl2tgba.test: More tests.
* src/ltltest/kind.test: Adjust.
* doc/tl/tl.tex: Mention the marked negated closure.
* src/ltlvisit/simplify.cc (reduce_sere_ltl): New function,
to factor the code of the []-> and <>-> rewrittings.
* src/ltltest/reduccmp.test: Add more tests.
* doc/tl/tl.tex: Document these rewritings.
* src/ltlvisit/simplify.cc: Here.
* doc/tl/tl.tex: Document then.
* src/ltlast/bunop.hh (as_KleenStar): New helper function.
* src/ltltest/reduccmp.test: Add more tests.
* src/ltltest/reduc.cc: Also display the resulting formula
without reduce_size_stricly.
* src/ltlvisit/snf.cc, src/ltlvisit/snf.hh: New files.
* src/ltlvisit/Makefile.am: Distribute them.
* src/ltlvisit/simplify.cc, src/ltlvisit/simplify.hh: Call snf(f) for
all f[*].
* src/ltltest/reduccmp.test: Test it.
* doc/tl/tl.tex, doc/tl/tl.bib: Document it.
It was a mistake to try to overload And/Or LTL operator for these when
trivial simplification are performed. The reason is so simple it is
embarassing: And(f,1)=f is a trivial identity that should not be
applied with AndRat. E.g. AndRat(a;b, 1) is equal to 0, not a;b.
* src/ltlast/multop.hh, src/ltlast/multop.cc: Add the AndRat and OrRat
operators.
* src/ltlparse/ltlparse.yy: Build them.
* src/ltlvisit/mark.cc, src/ltlvisit/simplify.cc,
src/ltlvisit/tostring.cc, src/tgba/formula2bdd.cc,
src/tgbaalgos/eltl2tgba_lacim.cc, src/tgbaalgos/ltl2taa.cc,
src/tgbaalgos/ltl2tgba_fm.cc, src/tgbaalgos/ltl2tgba_lacim.cc:
Adjust all switches.
* src/ltlast/bunop.hh, src/ltlast/bunop.cc, src/ltlvisit/randomltl.cc,
src/ltlvisit/simplify.cc, src/ltlvisit/tostring.cc,
src/tgbaalgos/ltl2tgba_fm.cc: Remove all traces of these two
operators since they are not handled like sugar.
* doc/tl/tl.tex: Adjust documentation to reflect the fact that these
two operators are sugar.
* src/ltlast/multop.hh, src/ltlast/multop.cc (all_but): New method
used to simplify the removal of one element of a multop.
* src/ltlvisit/simplify.cc: Implement the new rewriting rules.
* doc/tl/tl.tex: Document them.
* src/ltltest/reduccmp.test: Test them.
* src/ltlvisit/simplify.hh (ltl_simplifier_options): New option
reduce_size_stricly.
* src/ltlvisit/simplify.cc (simplify_visitor): Implement these
rules.
* src/ltltest/reduc.cc: Check with reduce_size_strictly unset or
set, but only use the latter result to check sizes.
* src/ltltest/reduccmp.test: Test them.
* doc/tl/tl.tex: Document them.
The actual rules are a bit more complex:
a & X(G(a&b...)&c...) = Ga & X(G(b...)&c...)
a | X(Fa | c) = F(a) | c
with the second rule being applied only if all XF can
be removed. See the documentation for an example.
* src/ltlvisit/simplify.cc: Implement these new rules.
* doc/tl/tl.tex: Document them.
* src/ltltest/reduccmp.test: Add test cases.
* src/ltlvisit/simplify.cc: Implement them here, and augment them
to support M, and W operators.
* src/ltltest/reduccmp.test: Add some tests.
* doc/tl/tl.tex (Simplifications Based on Implications): Document
these rules.
* doc/tl/tl.bib (babiak.12.tacas): New entry.
* src/ltlvisit/simplify.cc (simplify_visitor): Do it.
* src/ltltest/reduccmp.test: Add a test.
* doc/tl/tl.tex: Document it.
* src/ltlast/multop.cc: Fix the computation of is.accepting_eword
for Fusion. The Fusion operator never accepts [*0].
* src/ltlvisit/simplify.cc (syntactic_implication_aux): Refine
rules to deal with pure eventualities and purely universal
properties.
* src/ltltest/reduccmp.test: Add tests.
* src/ltlvisit/simplify.hh, src/ltlvisit/simplify.cc
(ltl_simplifier::ltl_simplifier, ltl_simplifier::get_dict): Make
it possible to supply and retrieve the dictionary used.
(ltl_simplifier::as_bdd): New function, exported from the cache.
* src/tgbaalgos/ltl2tgba_fm.cc (translate_dict): Store the
ltl_simplifier object.
(translate_dict::boolean_to_bdd): Call ltl_simplifier::as_bdd.
(translate_ratexp): New wrapper around the ratexp_trad_visitor,
calling boolean_to_bdd whenever possible.
(ratexp_trad_visitor): Do not deal with negated formulae, there
are necessarily Boolean and handled by translate_ratexp().
(ltl_visitor): Adjust to call translate_ratexp.
(ltl_to_tgba_fm): Adjust passing of the ltl_simplifier to the
translate_dict, and make sure everybody is using the same
dictionary.
* src/tgbatest/ltl2tgba.cc: Pass the dictionary to the
ltl_simplifier.
* src/ltlvisit/simplify.cc, src/ltlvisit/simplify.hh
(are_equivalent): Export this function from the cache.
* src/ltltest/reduc.cc, src/ltltest/equals.cc: Use
are_equivalent() to check that the reductions are legitimate.
So that we can latter use some combined optimizations.
* src/ltlvisit/simplify.hh, src/ltlvisit/simplify.cc: Integrate
the code from syntimpl.cc
* src/ltlvisit/syntimpl.hh, src/ltlvisit/syntimpl.cc: Delete. All
code has been moved above.
* src/ltlvisit/Makefile.am: Adjust.
* src/ltltest/syntimpl.cc: Adjust code.
* src/ltlvisit/simplify.hh, src/ltlvisit/simplify.cc
(ltl_simplify::negative_normal_form): Remove the third
parameter and always rewrite XOR, =>, and <=>. This avoid
problems with the cache, that could have been populated with
a different value for this third parameter.
* src/ltltest/reduc.cc, src/tgbaalgos/ltl2tgba_fm.cc: Adjust
calls to negative_normal_form().
* src/ltltest/nenoform.test: Adjust tests.
