Commit 516e9536 authored by Maximilien Colange's avatar Maximilien Colange

LAR made smarter with symmetry-based degeneralization

* spot/twaalgos/toparity.cc: here
* spot/twa/acc.hh, spot/twa/acc.cc: compute symmetries of an acceptance
  condition
* tests/python/accparse2.py, tests/python/toparity.py: test it
parent 3303b86a
Pipeline #3114 passed with stages
in 144 minutes and 6 seconds
......@@ -958,7 +958,6 @@ namespace spot
const acc_cond::acc_code& rhs)
{
auto used = lhs.used_sets() | rhs.used_sets();
unsigned c = used.count();
unsigned umax = used.max_set();
......@@ -975,6 +974,54 @@ namespace spot
}
}
std::vector<unsigned>
acc_cond::acc_code::symmetries() const
{
auto used = used_sets();
unsigned umax = used.max_set();
bdd_allocator ba;
int base = ba.allocate_variables(umax+2);
assert(base == 0);
std::vector<bdd> r;
for (unsigned i = 0; r.size() < umax; ++i)
r.emplace_back(bdd_ithvar(base++));
bdd bddcode = to_bdd_rec(&back(), &r[0]);
bdd tmp;
std::vector<unsigned> res(umax);
for (unsigned x = 0; x < umax; ++x)
res[x] = x;
for (unsigned x : used.sets())
for (unsigned y : used.sets())
{
if (x >= y)
continue;
if (res[x] != x)
continue;
{
bddPair* p = bdd_newpair();
bdd_setpair(p, x, umax + 0);
bdd_setpair(p, y, umax + 1);
tmp = bdd_replace(bddcode, p);
bdd_freepair(p);
p = bdd_newpair();
bdd_setpair(p, umax + 0, y);
bdd_setpair(p, umax + 1, x);
tmp = bdd_replace(tmp, p);
bdd_freepair(p);
}
if (tmp == bddcode)
res[y] = x;
}
return res;
}
bool acc_cond::is_parity(bool& max, bool& odd, bool equiv) const
{
unsigned sets = num_;
......
......@@ -904,6 +904,12 @@ namespace spot
trival maybe_accepting(mark_t infinitely_often,
mark_t always_present) const;
// Return all symmetric marks of the condition.
// If two marks x and y are symmetric, it means that swapping them does
// not change (logically) the acc_code.
// In the returned vector, each mark points to the "root" of its symmetry
// class.
std::vector<unsigned> symmetries() const;
// Remove all the acceptance sets in rem.
//
......
......@@ -34,10 +34,19 @@ namespace spot
{
unsigned state;
std::vector<unsigned> perm;
std::vector<unsigned> count;
bool operator<(const lar_state& s) const
{
return state == s.state ? perm < s.perm : state < s.state;
if (state == s.state)
{
if (perm == s.perm)
return count < s.count;
else
return perm < s.perm;
}
else
return state < s.state;
}
std::string to_string() const
......@@ -46,11 +55,12 @@ namespace spot
s << state << " [";
for (unsigned i = 0; i != perm.size(); ++i)
{
s << perm[i];
s << perm[i] << '@' << count[i];
if (i < perm.size() - 1)
s << ',';
s << ", ";
}
s << ']';
return s.str();
}
};
......@@ -71,10 +81,42 @@ namespace spot
twa_graph_ptr run()
{
auto symm = aut_->acc().get_acceptance().symmetries();
// we need to know for each symmetry class:
// - its id
// - its elements in order (any arbitrary order will do)
// - its size
std::vector<acc_cond::mark_t> classes;
std::vector<unsigned> acc2class(aut_->num_sets(), -1U);
std::vector<unsigned> accpos(aut_->num_sets(), -1U);
for (unsigned k : aut_->acc().all_sets().sets())
{
unsigned r = symm[k];
if (k == r) // new class
{
acc2class[k] = classes.size();
accpos[k] = 0;
classes.push_back({k});
}
else
{
unsigned c = acc2class[r];
acc2class[k] = c;
accpos[k] = classes[c].count();
classes[c].set(k);
}
}
// create resulting automaton
res_ = make_twa_graph(aut_->get_dict());
res_->copy_ap_of(aut_);
std::deque<lar_state> todo;
struct stack_elem
{
unsigned num;
lar_state s;
};
std::deque<stack_elem> todo;
auto get_state = [this, &todo](const lar_state& s)
{
auto it = lar2num.emplace(s, -1U);
......@@ -82,16 +124,21 @@ namespace spot
{
unsigned nb = res_->new_state();
it.first->second = nb;
todo.push_back(s);
todo.push_back({nb, s});
}
return it.first->second;
};
// initial state
{
std::vector<unsigned> p0;
for (unsigned k : aut_->acc().all_sets().sets())
p0.push_back(k);
lar_state s0{aut_->get_init_state_number(), p0};
std::vector<unsigned> c0;
for (unsigned i = 0; i < classes.size(); ++i)
{
p0.push_back(i);
c0.push_back(0);
}
lar_state s0{aut_->get_init_state_number(), p0, c0};
unsigned init = get_state(s0); // put s0 in todo
res_->set_init_state(init);
}
......@@ -99,39 +146,67 @@ namespace spot
// main loop
while (!todo.empty())
{
lar_state current = todo.front();
lar_state current = std::move(todo.front().s);
unsigned src_num = todo.front().num;
todo.pop_front();
// TODO todo could store this number to avoid one lookup
unsigned src_num = get_state(current);
for (const auto& e : aut_->out(current.state))
{
// find the new permutation
std::vector<unsigned> new_perm = current.perm;
std::vector<unsigned> new_count = current.count;
std::vector<unsigned> hits(new_count.size(), 0);
unsigned h = 0;
for (unsigned k : e.acc.sets())
{
auto it = std::find(new_perm.begin(), new_perm.end(), k);
h = std::max(h, unsigned(new_perm.end() - it));
std::rotate(it, it+1, new_perm.end());
unsigned c = acc2class[k];
if (accpos[k] == new_count[c])
new_count[c] += 1;
else
++hits[c];
if (new_count[c] == classes[c].count())
{
new_count[c] = 0;
auto it =
std::find(new_perm.begin(), new_perm.end(), c);
assert(it != new_perm.end());
h = std::max(h, unsigned(new_perm.end() - it));
std::rotate(it, it+1, new_perm.end());
}
}
lar_state dst{e.dst, new_perm};
lar_state dst{e.dst, new_perm, new_count};
unsigned dst_num = get_state(dst);
// do the h last elements satisfy the acceptance condition?
acc_cond::mark_t m(new_perm.end() - h, new_perm.end());
acc_cond::mark_t m({});
for (auto c = new_perm.end() - h; c != new_perm.end(); ++c)
m |= classes[*c];
for (auto c = new_perm.begin(); c != new_perm.end() - h; ++c)
{
for (unsigned k : classes[*c].sets())
{
if (hits[*c] == 0)
break;
m.set(k);
--hits[*c];
}
}
if (aut_->acc().accepting(m))
res_->new_edge(src_num, dst_num, e.cond, {2*h});
res_->new_edge(src_num, dst_num, e.cond, {2*m.count()});
else
res_->new_edge(src_num, dst_num, e.cond, {2*h+1});
res_->new_edge(src_num, dst_num, e.cond, {2*m.count()+1});
}
}
// parity max even
res_->set_acceptance(2*aut_->num_sets() + 2,
acc_cond::acc_code::parity(true, false, 2*aut_->num_sets() + 2));
unsigned nb_colors = 2*aut_->num_sets() + 2;
res_->set_acceptance(nb_colors,
acc_cond::acc_code::parity(true, false, nb_colors));
// inherit properties of the input automaton
res_->prop_copy(aut_, { false, false, true, false, true, true });
if (pretty_print)
{
......
# -*- mode: python; coding: utf-8 -*-
# Copyright (C) 2015, 2017 Laboratoire de Recherche et Développement
# Copyright (C) 2015, 2017-2018 Laboratoire de Recherche et Développement
# de l'Epita
#
# This file is part of Spot, a model checking library.
......@@ -107,3 +107,10 @@ assert(a.is_streett() == -1)
a.set_acceptance('(Fin(0)|Inf(1))&(Inf(1)|Fin(0))&(Inf(3)|Fin(2))')
assert(a.is_rabin() == -1)
assert(a.is_streett() == 2)
a = spot.acc_code('Inf(0)&Inf(1)&Inf(3) | Fin(0)&(Fin(1)|Fin(3))')
u = a.symmetries()
assert u[0] == 0
assert u[1] == 1
assert u[2] == 2
assert u[3] == 1
......@@ -20,6 +20,21 @@
import spot
a = spot.automaton("""HOA: v1
States: 1
Start: 0
AP: 2 "a" "b"
Acceptance: 2 Inf(0)|Inf(1)
--BODY--
State: 0
[0&1] 0 {0 1}
[0&!1] 0 {0}
[!0&1] 0 {1}
[!0&!1] 0
--END--""")
p = spot.to_parity(a)
assert spot.are_equivalent(a, p)
for f in spot.randltl(4, 400):
d = spot.translate(f, "det", "G")
p = spot.to_parity(d)
......
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