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Add an algorithm (from Couvreur) working on BDDs to reduce the

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size of TGBAs represented as BDDs by deleting unaccepting SCCs.

* src/eltlparse/eltlparse.yy: Remove a warning.
* src/tgba/tgbabddconcrete.cc, src/tgba/tgbabddconcrete.hh,
src/tgba/tgbabddcoredata.cc, src/tgba/tgbabddcoredata.hh: Add a
new function delete_unaccepting_scc in both classes.
* src/tgbatest/eltl2tgba.cc, src/tgbatest/spotlbtt.test: Use this
new function in LaCIM for ELTL and bench it.
* src/tgbatest/defs.in: Fix it.
* bench/ltl2tgba/algorithms, bench/ltl2tgba/defs.in: Add LaCIM for
ELTL in benchs.
This commit is contained in:
Damien Lefortier 2009-09-04 21:29:29 +02:00
parent dc8cb56b67
commit edd4b2b532
11 changed files with 136 additions and 7 deletions
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63
src/tgba/tgbabddcoredata.cc
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@ -130,4 +130,67 @@ namespace spot
acc_set &= acc;
negacc_set &= !acc;
}
void
tgba_bdd_core_data::delete_unaccepting_scc(bdd init)
{
bdd er = bdd_exist(relation, var_set); /// existsRelation
bdd s0 = bddfalse;
bdd s1 = bdd_exist(bdd_exist(init & relation, var_set), now_set);
s1 = bdd_replace(s1, dict->next_to_now);
/// Find all reachable states
while (s0 != s1)
{
s0 = s1;
/// Compute s1 = succ(s0) | s
s1 = bdd_replace(bdd_exist(s0 & er, now_set), dict->next_to_now) | s0;
}
/// Find states which can be visited infinitely often while seeing
/// all acceptance conditions
s0 = bddfalse;
while (s0 != s1)
{
s0 = s1;
bdd all = all_acceptance_conditions;
while (all != bddfalse)
{
bdd next = bdd_satone(all);
all -= next;
s1 = infinitely_often(s1, next, er);
}
}
relation = s0 & (relation & bdd_replace(s0, dict->now_to_next));
}
bdd
tgba_bdd_core_data::infinitely_often(bdd s, bdd acc, bdd er)
{
bdd ar = acc & (relation & acceptance_conditions); /// accRelation
bdd s0 = bddfalse;
bdd s1 = s;
while (s0 != s1)
{
s0 = s1;
bdd as = bdd_replace(s0, dict->now_to_next) & ar;
as = bdd_exist(bdd_exist(as, next_set), var_set) & s0;
/// Do predStar
bdd s0_ = bddfalse;
bdd s1_ = bdd_exist(as, acc_set);
while (s0_ != s1_)
{
s0_ = s1_;
/// Compute s1_ = pred(s0_) | s0_
s1_ = bdd_exist(er & bdd_replace(s0_, dict->now_to_next), next_set);
s1_ = (s1_ & s0) | s0_;
}
s1 = s0_;
}
return s0;
}
}