spot/spot/twaalgos/genem.hh
Alexandre Duret-Lutz 7f0ef7ad59 genem: improve the worst case
* spot/twaalgos/genem.cc, spot/twaalgos/genem.hh: Improve the worst
case by not recurring twice into each disjunct individually.  Keep
the previous two implementation available and add a function
generic_emptiness_check_select_version() so we can benchmark the
difference.
* tests/python/genem.py: Test the three versions.
2020-03-06 12:38:20 +01:00

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3 KiB
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// -*- coding: utf-8 -*-
// Copyright (C) 2017-2020 Laboratoire de Recherche et Developpement
// de l'Epita (LRDE).
//
// 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/>.
#pragma once
#include <spot/twaalgos/emptiness.hh>
#include <spot/twaalgos/sccinfo.hh>
namespace spot
{
/// \ingroup emptiness_check_algorithms
/// \brief Emptiness check of an automaton, for any acceptance condition.
///
/// Currently only implemented for twa_graph automata, i.e., not automata
/// constructed on-the-fly.
///
/// \cite baier.19.atva
SPOT_API bool
generic_emptiness_check(const const_twa_graph_ptr& aut);
/// \ingroup emptiness_check_algorithms
/// \brief Accepting run search in an automaton, for any acceptance condition.
/// \return An accepting run over the automaton, or nullptr if the language is
/// empty.
///
/// Currently only implemented for twa_graph automata, i.e., not automata
/// constructed on-the-fly.
SPOT_API twa_run_ptr
generic_accepting_run(const const_twa_graph_ptr& aut);
/// \ingroup emptiness_check_algorithms
/// \brief Emptiness check of one SCC, for any acceptance condition.
///
/// \cite baier.19.atva
SPOT_API bool
generic_emptiness_check_for_scc(const scc_info& si, unsigned scc);
/// \ingroup emptiness_check_algorithms
/// \brief Emptiness check of one SCC, for any acceptance condition.
///
/// This version makes it possible to ignore the acceptance
/// condition of the automaton, and use \a forced_acc.
///
/// \cite baier.19.atva
SPOT_API bool
generic_emptiness_check_for_scc(const scc_info& si, unsigned scc,
const acc_cond& forced_acc);
/// \ingroup emptiness_check_algorithms
///
/// Select the version of the generic-emptiness check to use, this
/// is mainly for benchmarking purpose.
///
/// We currently have three versions:
/// - "spot28" is similar to the algorithm described our ATVA'19 paper
/// \cite baier.19.atva , however it has an implementation bug
/// that cause superfluous recursive calls to be performed (the
/// result is still correct.
/// - "atva19" is similar to the algorithm described our ATVA'19 paper
/// \cite baier.19.atva , with the above bug fixed.
/// - "spot29" improves upon the worst case of atva19. This is
/// the default.
SPOT_API void
generic_emptiness_check_select_version(const char* emversion = nullptr);
}