14bee1ae7f
Fixes #174. * spot/twaalgos/totgba.hh, spot/twaalgos/totgba.cc (to_generalized_streett, to_generalized_rabin): New functions. * spot/twa/acc.hh: Declare more methods as static. * bin/autfilt.cc: Implement --generalized-rabin and --generalized-streett options. * NEWS: Mention these. * tests/core/gragsa.test: New file. * tests/Makefile.am: Add it.
559 lines
17 KiB
C++
559 lines
17 KiB
C++
// -*- coding: utf-8 -*-
|
|
// Copyright (C) 2015, 2016 Laboratoire de Recherche et Développement
|
|
// de l'Epita.
|
|
//
|
|
// This file is part of Spot, a model checking library.
|
|
//
|
|
// Spot is free software; you can redistribute it and/or modify it
|
|
// under the terms of the GNU General Public License as published by
|
|
// the Free Software Foundation; either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// Spot is distributed in the hope that it will be useful, but WITHOUT
|
|
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
|
// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
|
|
// License for more details.
|
|
//
|
|
// You should have received a copy of the GNU General Public License
|
|
// along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
#include <spot/twaalgos/totgba.hh>
|
|
#include <spot/twaalgos/remfin.hh>
|
|
#include <spot/twaalgos/cleanacc.hh>
|
|
#include <spot/twaalgos/sccinfo.hh>
|
|
#include <spot/twa/twagraph.hh>
|
|
#include <deque>
|
|
#include <tuple>
|
|
|
|
namespace spot
|
|
{
|
|
namespace
|
|
{
|
|
struct st2gba_state
|
|
{
|
|
acc_cond::mark_t pend;
|
|
unsigned s;
|
|
|
|
st2gba_state(unsigned st, acc_cond::mark_t bv = -1U):
|
|
pend(bv), s(st)
|
|
{
|
|
}
|
|
};
|
|
|
|
struct st2gba_state_hash
|
|
{
|
|
size_t
|
|
operator()(const st2gba_state& s) const
|
|
{
|
|
std::hash<acc_cond::mark_t> h;
|
|
return s.s ^ h(s.pend);
|
|
}
|
|
};
|
|
|
|
struct st2gba_state_equal
|
|
{
|
|
bool
|
|
operator()(const st2gba_state& left,
|
|
const st2gba_state& right) const
|
|
{
|
|
if (left.s != right.s)
|
|
return false;
|
|
return left.pend == right.pend;
|
|
}
|
|
};
|
|
|
|
typedef std::vector<acc_cond::mark_t> terms_t;
|
|
|
|
terms_t cnf_terms(const acc_cond::acc_code& code)
|
|
{
|
|
assert(!code.empty());
|
|
terms_t res;
|
|
auto pos = &code.back();
|
|
auto end = &code.front();
|
|
if (pos->op == acc_cond::acc_op::And)
|
|
--pos;
|
|
while (pos >= end)
|
|
{
|
|
auto term_end = pos - 1 - pos->size;
|
|
if (pos->op == acc_cond::acc_op::Or)
|
|
--pos;
|
|
acc_cond::mark_t m = 0U;
|
|
while (pos > term_end)
|
|
{
|
|
assert(pos->op == acc_cond::acc_op::Inf);
|
|
m |= pos[-1].mark;
|
|
pos -= 2;
|
|
}
|
|
res.push_back(m);
|
|
}
|
|
return res;
|
|
}
|
|
}
|
|
|
|
|
|
// Specialized conversion for Streett -> TGBA
|
|
// ============================================
|
|
//
|
|
// Christof Löding's Diploma Thesis: Methods for the
|
|
// Transformation of ω-Automata: Complexity and Connection to
|
|
// Second Order Logic. Section 3.4.3, gives a transition
|
|
// from Streett with |Q| states to BA with |Q|*(4^n-3^n+2)
|
|
// states, if n is the number of acceptance pairs.
|
|
//
|
|
// Duret-Lutz et al. (ATVA'2009): On-the-fly Emptiness Check of
|
|
// Transition-based Streett Automata. Section 3.3 contains a
|
|
// conversion from transition-based Streett Automata to TGBA using
|
|
// the generalized Büchi acceptance to limit the explosion. It goes
|
|
// from Streett with |Q| states to (T)GBA with |Q|*(2^n+1) states.
|
|
// However the definition of the number of acceptance sets in that
|
|
// paper is suboptimal: only n are needed, not 2^n.
|
|
//
|
|
// This implements this second version.
|
|
twa_graph_ptr
|
|
streett_to_generalized_buchi(const const_twa_graph_ptr& in)
|
|
{
|
|
// While "t" is Streett, it is also generalized Büchi, so
|
|
// do not do anything.
|
|
if (in->acc().is_generalized_buchi())
|
|
return std::const_pointer_cast<twa_graph>(in);
|
|
int p = in->acc().is_streett();
|
|
if (p <= 0)
|
|
throw std::runtime_error("streett_to_generalized_buchi() should only be"
|
|
" called on automata with Streett acceptance");
|
|
|
|
// In Streett acceptance, inf sets are odd, while fin sets are
|
|
// even.
|
|
acc_cond::mark_t inf;
|
|
acc_cond::mark_t fin;
|
|
std::tie(inf, fin) = in->get_acceptance().used_inf_fin_sets();
|
|
assert((inf >> 1U) == fin);
|
|
|
|
scc_info si(in);
|
|
|
|
// Compute the acceptance sets present in each SCC
|
|
unsigned nscc = si.scc_count();
|
|
std::vector<std::tuple<acc_cond::mark_t, acc_cond::mark_t, bool>> sccfi;
|
|
sccfi.reserve(nscc);
|
|
for (unsigned s = 0; s < nscc; ++s)
|
|
{
|
|
auto acc = si.acc_sets_of(s); // {0,1,2,3,4,6,7,9}
|
|
auto acc_fin = acc & fin; // {0, 2, 4,6}
|
|
auto acc_inf = acc & inf; // { 1, 3, 7,9}
|
|
auto fin_wo_inf = acc_fin - (acc_inf >> 1U); // {4}
|
|
auto inf_wo_fin = acc_inf - (acc_fin << 1U); // {9}
|
|
sccfi.emplace_back(fin_wo_inf, inf_wo_fin, acc_fin == 0U);
|
|
}
|
|
|
|
auto out = make_twa_graph(in->get_dict());
|
|
out->copy_ap_of(in);
|
|
out->prop_copy(in, {false, false, false, true});
|
|
out->set_generalized_buchi(p);
|
|
acc_cond::mark_t outall = out->acc().all_sets();
|
|
|
|
// Map st2gba pairs to the state numbers used in out.
|
|
typedef std::unordered_map<st2gba_state, unsigned,
|
|
st2gba_state_hash,
|
|
st2gba_state_equal> bs2num_map;
|
|
bs2num_map bs2num;
|
|
|
|
// Queue of states to be processed.
|
|
typedef std::deque<st2gba_state> queue_t;
|
|
queue_t todo;
|
|
|
|
st2gba_state s(in->get_init_state_number());
|
|
bs2num[s] = out->new_state();
|
|
todo.push_back(s);
|
|
|
|
bool sbacc = in->prop_state_acc().is_true();
|
|
|
|
// States of the original automaton are marked with s.pend == -1U.
|
|
const acc_cond::mark_t orig_copy(-1U);
|
|
|
|
while (!todo.empty())
|
|
{
|
|
s = todo.front();
|
|
todo.pop_front();
|
|
unsigned src = bs2num[s];
|
|
|
|
unsigned scc_src = si.scc_of(s.s);
|
|
bool maybe_acc_scc = !si.is_rejecting_scc(scc_src);
|
|
|
|
acc_cond::mark_t scc_fin_wo_inf;
|
|
acc_cond::mark_t scc_inf_wo_fin;
|
|
bool no_fin;
|
|
std::tie(scc_fin_wo_inf, scc_inf_wo_fin, no_fin) = sccfi[scc_src];
|
|
|
|
for (auto& t: in->out(s.s))
|
|
{
|
|
acc_cond::mark_t pend = s.pend;
|
|
acc_cond::mark_t acc = 0U;
|
|
|
|
bool maybe_acc = maybe_acc_scc && (scc_src == si.scc_of(t.dst));
|
|
|
|
if (pend != orig_copy)
|
|
{
|
|
if (!maybe_acc)
|
|
continue;
|
|
// No point going to some place we will never leave
|
|
if (t.acc & scc_fin_wo_inf)
|
|
continue;
|
|
// For any Fin set we see, we want to see the
|
|
// corresponding Inf set.
|
|
pend |= (t.acc & fin) << 1U;
|
|
pend -= t.acc & inf;
|
|
// Label this transition with all non-pending
|
|
// inf sets. The strip will shift everything
|
|
// to the correct numbers in the targets.
|
|
acc = (inf - pend).strip(fin) & outall;
|
|
// Adjust the pending sets to what will be necessary
|
|
// required on the destination state.
|
|
if (sbacc)
|
|
{
|
|
auto a = in->state_acc_sets(t.dst);
|
|
if (a & scc_fin_wo_inf)
|
|
continue;
|
|
pend |= (a & fin) << 1U;
|
|
pend -= a & inf;
|
|
}
|
|
pend |= scc_inf_wo_fin;
|
|
}
|
|
else if (no_fin && maybe_acc)
|
|
{
|
|
assert(maybe_acc);
|
|
acc = outall;
|
|
}
|
|
|
|
st2gba_state d(t.dst, pend);
|
|
// Have we already seen this destination?
|
|
unsigned dest;
|
|
auto dres = bs2num.emplace(d, 0);
|
|
if (!dres.second)
|
|
{
|
|
dest = dres.first->second;
|
|
}
|
|
else // No, this is a new state
|
|
{
|
|
dest = dres.first->second = out->new_state();
|
|
todo.push_back(d);
|
|
}
|
|
out->new_edge(src, dest, t.cond, acc);
|
|
|
|
// Nondeterministically jump to level ∅. We need to do
|
|
// that only once per cycle. As an approximation, we
|
|
// only to that for transition where t.src >= t.dst as
|
|
// this has to occur at least once per cycle.
|
|
if (pend == orig_copy && (t.src >= t.dst) && maybe_acc && !no_fin)
|
|
{
|
|
acc_cond::mark_t pend = 0U;
|
|
if (sbacc)
|
|
{
|
|
auto a = in->state_acc_sets(t.dst);
|
|
if (a & scc_fin_wo_inf)
|
|
continue;
|
|
pend = (a & fin) << 1U;
|
|
pend -= a & inf;
|
|
}
|
|
st2gba_state d(t.dst, pend | scc_inf_wo_fin);
|
|
// Have we already seen this destination?
|
|
unsigned dest;
|
|
auto dres = bs2num.emplace(d, 0);
|
|
if (!dres.second)
|
|
{
|
|
dest = dres.first->second;
|
|
}
|
|
else // No, this is a new state
|
|
{
|
|
dest = dres.first->second = out->new_state();
|
|
todo.push_back(d);
|
|
}
|
|
out->new_edge(src, dest, t.cond);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
// for (auto s: bs2num)
|
|
// {
|
|
// std::cerr << s.second << " ("
|
|
// << s.first.s << ", ";
|
|
// if (s.first.pend == orig_copy)
|
|
// std::cerr << "-)\n";
|
|
// else
|
|
// std::cerr << s.first.pend << ")\n";
|
|
// }
|
|
return out;
|
|
}
|
|
|
|
twa_graph_ptr
|
|
streett_to_generalized_buchi_maybe(const const_twa_graph_ptr& in)
|
|
{
|
|
static int min = [&]() {
|
|
const char* c = getenv("SPOT_STREETT_CONV_MIN");
|
|
if (!c)
|
|
return 3;
|
|
errno = 0;
|
|
int val = strtol(c, nullptr, 10);
|
|
if (val < 0 || errno != 0)
|
|
throw std::runtime_error("unexpected value for SPOT_STREETT_CONV_MIN");
|
|
return val;
|
|
}();
|
|
if (min == 0 || min > in->acc().is_streett())
|
|
return nullptr;
|
|
else
|
|
return streett_to_generalized_buchi(in);
|
|
}
|
|
|
|
/// \brief Take an automaton with any acceptance condition and return
|
|
/// an equivalent Generalized Büchi automaton.
|
|
twa_graph_ptr
|
|
to_generalized_buchi(const const_twa_graph_ptr& aut)
|
|
{
|
|
auto maybe = streett_to_generalized_buchi_maybe(aut);
|
|
if (maybe)
|
|
return maybe;
|
|
|
|
auto res = remove_fin(cleanup_acceptance(aut));
|
|
if (res->acc().is_generalized_buchi())
|
|
return res;
|
|
|
|
auto cnf = res->get_acceptance().to_cnf();
|
|
// If we are very lucky, building a CNF actually gave us a GBA...
|
|
if (cnf.empty() ||
|
|
(cnf.size() == 2 && cnf.back().op == acc_cond::acc_op::Inf))
|
|
{
|
|
res->set_acceptance(res->num_sets(), cnf);
|
|
cleanup_acceptance_here(res);
|
|
return res;
|
|
}
|
|
|
|
// Handle false specifically. We want the output
|
|
// an automaton with Acceptance: t, that has a single
|
|
// state without successor.
|
|
if (cnf.is_f())
|
|
{
|
|
assert(cnf.front().mark == 0U);
|
|
res = make_twa_graph(aut->get_dict());
|
|
res->set_init_state(res->new_state());
|
|
res->prop_state_acc(true);
|
|
res->prop_weak(true);
|
|
res->prop_deterministic(true);
|
|
res->prop_stutter_invariant(true);
|
|
return res;
|
|
}
|
|
|
|
auto terms = cnf_terms(cnf);
|
|
unsigned nterms = terms.size();
|
|
assert(nterms > 0);
|
|
res->set_generalized_buchi(nterms);
|
|
|
|
for (auto& t: res->edges())
|
|
{
|
|
acc_cond::mark_t cur_m = t.acc;
|
|
acc_cond::mark_t new_m = 0U;
|
|
for (unsigned n = 0; n < nterms; ++n)
|
|
if (cur_m & terms[n])
|
|
new_m.set(n);
|
|
t.acc = new_m;
|
|
}
|
|
return res;
|
|
}
|
|
|
|
namespace
|
|
{
|
|
// If the DNF is
|
|
// Fin(1)&Inf(2)&Inf(4) | Fin(2)&Fin(3)&Inf(1) |
|
|
// Inf(1)&Inf(3) | Inf(1)&Inf(2) | Fin(4)
|
|
// this returns the following vector of pairs:
|
|
// [({1}, {2,4})
|
|
// ({2,3}, {1}),
|
|
// ({}, {1,3}),
|
|
// ({}, {2}),
|
|
// ({4}, t)]
|
|
static std::vector<std::pair<acc_cond::mark_t, acc_cond::mark_t>>
|
|
split_dnf_acc(const acc_cond::acc_code& acc)
|
|
{
|
|
std::vector<std::pair<acc_cond::mark_t, acc_cond::mark_t>> res;
|
|
if (acc.empty())
|
|
{
|
|
res.emplace_back(0U, 0U);
|
|
return res;
|
|
}
|
|
auto pos = &acc.back();
|
|
if (pos->op == acc_cond::acc_op::Or)
|
|
--pos;
|
|
auto start = &acc.front();
|
|
while (pos > start)
|
|
{
|
|
if (pos->op == acc_cond::acc_op::Fin)
|
|
{
|
|
// We have only a Fin term, without Inf. In this case
|
|
// only, the Fin() may encode a disjunction of sets.
|
|
for (auto s: pos[-1].mark.sets())
|
|
res.emplace_back(acc_cond::mark_t({s}), 0U);
|
|
pos -= pos->size + 1;
|
|
}
|
|
else
|
|
{
|
|
// We have a conjunction of Fin and Inf sets.
|
|
auto end = pos - pos->size - 1;
|
|
acc_cond::mark_t fin = 0U;
|
|
acc_cond::mark_t inf = 0U;
|
|
while (pos > end)
|
|
{
|
|
switch (pos->op)
|
|
{
|
|
case acc_cond::acc_op::And:
|
|
--pos;
|
|
break;
|
|
case acc_cond::acc_op::Fin:
|
|
fin |= pos[-1].mark;
|
|
assert(pos[-1].mark.count() == 1);
|
|
pos -= 2;
|
|
break;
|
|
case acc_cond::acc_op::Inf:
|
|
inf |= pos[-1].mark;
|
|
pos -= 2;
|
|
break;
|
|
case acc_cond::acc_op::FinNeg:
|
|
case acc_cond::acc_op::InfNeg:
|
|
case acc_cond::acc_op::Or:
|
|
SPOT_UNREACHABLE();
|
|
break;
|
|
}
|
|
}
|
|
assert(pos == end);
|
|
res.emplace_back(fin, inf);
|
|
}
|
|
}
|
|
return res;
|
|
}
|
|
|
|
|
|
static twa_graph_ptr
|
|
to_generalized_rabin_aux(const const_twa_graph_ptr& aut,
|
|
bool share_inf, bool complement)
|
|
{
|
|
auto res = cleanup_acceptance(aut);
|
|
auto oldacc = res->get_acceptance();
|
|
if (complement)
|
|
res->set_acceptance(res->acc().num_sets(), oldacc.complement());
|
|
|
|
{
|
|
std::vector<unsigned> pairs;
|
|
if (res->acc().is_generalized_rabin(pairs))
|
|
{
|
|
if (complement)
|
|
res->set_acceptance(res->acc().num_sets(), oldacc);
|
|
return res;
|
|
}
|
|
}
|
|
auto dnf = res->get_acceptance().to_dnf();
|
|
if (dnf.is_f())
|
|
{
|
|
if (complement)
|
|
res->set_acceptance(0, acc_cond::acc_code::t());
|
|
return res;
|
|
}
|
|
|
|
auto v = split_dnf_acc(dnf);
|
|
|
|
// Decide how we will rename each input set.
|
|
//
|
|
// inf_rename is only used if hoa_style=false, to
|
|
// reuse previously used Inf sets.
|
|
|
|
unsigned ns = res->num_sets();
|
|
std::vector<acc_cond::mark_t> rename(ns);
|
|
std::vector<unsigned> inf_rename(ns);
|
|
|
|
unsigned next_set = 0;
|
|
// The output acceptance conditions.
|
|
acc_cond::acc_code code =
|
|
complement ? acc_cond::acc_code::t() : acc_cond::acc_code::f();
|
|
for (auto& i: v)
|
|
{
|
|
unsigned fin_set = 0U;
|
|
|
|
if (!complement)
|
|
{
|
|
for (auto s: i.first.sets())
|
|
rename[s].set(next_set);
|
|
fin_set = next_set++;
|
|
}
|
|
|
|
acc_cond::mark_t infsets = 0U;
|
|
|
|
if (share_inf)
|
|
for (auto s: i.second.sets())
|
|
{
|
|
unsigned n = inf_rename[s];
|
|
if (n == 0)
|
|
n = inf_rename[s] = next_set++;
|
|
rename[s].set(n);
|
|
infsets.set(n);
|
|
}
|
|
else // HOA style
|
|
{
|
|
for (auto s: i.second.sets())
|
|
{
|
|
unsigned n = next_set++;
|
|
rename[s].set(n);
|
|
infsets.set(n);
|
|
}
|
|
}
|
|
|
|
// The definition of Streett wants the Fin first in clauses,
|
|
// so we do the same for generalized Streett since HOA does
|
|
// not specify anything. See
|
|
// https://github.com/adl/hoaf/issues/62
|
|
if (complement)
|
|
{
|
|
for (auto s: i.first.sets())
|
|
rename[s].set(next_set);
|
|
fin_set = next_set++;
|
|
|
|
auto pair = acc_cond::inf({fin_set});
|
|
pair |= acc_cond::acc_code::fin(infsets);
|
|
pair &= std::move(code);
|
|
code = std::move(pair);
|
|
}
|
|
else
|
|
{
|
|
auto pair = acc_cond::acc_code::inf(infsets);
|
|
pair &= acc_cond::fin({fin_set});
|
|
pair |= std::move(code);
|
|
code = std::move(pair);
|
|
}
|
|
}
|
|
|
|
// Fix the automaton
|
|
res->set_acceptance(next_set, code);
|
|
for (auto& e: res->edges())
|
|
{
|
|
acc_cond::mark_t m = 0U;
|
|
for (auto s: e.acc.sets())
|
|
m |= rename[s];
|
|
e.acc = m;
|
|
}
|
|
return res;
|
|
}
|
|
|
|
|
|
}
|
|
|
|
|
|
|
|
twa_graph_ptr
|
|
to_generalized_rabin(const const_twa_graph_ptr& aut,
|
|
bool share_inf)
|
|
{
|
|
return to_generalized_rabin_aux(aut, share_inf, false);
|
|
}
|
|
|
|
twa_graph_ptr
|
|
to_generalized_streett(const const_twa_graph_ptr& aut,
|
|
bool share_fin)
|
|
{
|
|
return to_generalized_rabin_aux(aut, share_fin, true);
|
|
}
|
|
}
|