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* src/tgbaalgos/magic.cc: rewrite to externalize the heap and

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prepare it to a bit state hashing version.
* src/tgbaalgos/magic.hh: adapt to the new interface of
magic_search and se05_search.
* src/tgbaalgos/se05.cc: new file.
* src/tgbaalgos/Makefile.am: Add it.
* src/tgbatest/ltl2tgba.cc: Add new emptiness check.
* src/tgbatest/emptchk.test: more tests.
* src/tgbatest/dfs.test: new file.
* src/tgbatest/Makefile.am: Add it.
This commit is contained in:
Denis Poitrenaud 2004-11-09 17:22:58 +00:00
parent 908b6129f4
commit f52082bcfb
9 changed files with 1226 additions and 254 deletions
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227
src/tgbaalgos/magic.hh
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@ -22,107 +22,148 @@
#ifndef SPOT_TGBAALGOS_MAGIC_HH
# define SPOT_TGBAALGOS_MAGIC_HH
#include "misc/hash.hh"
#include <list>
#include <utility>
#include <ostream>
#include "tgba/tgbatba.hh"
#include "tgba/tgba.hh"
#include "emptiness.hh"
namespace spot
{
/// \brief Emptiness check on spot::tgba_tba_proxy automata using
/// the Magic Search algorithm.
/// \brief Returns an emptiness check on the spot::tgba automaton \a a.
///
/// \pre The automaton \a a must have at most one accepting condition (i.e.
/// it is a TBA).
///
/// The method \a check() of the returned checker can be called several times
/// (until it returns a null pointer) to enumerate all the visited accepting
/// paths. The method visits only a finite set of accepting paths.
///
/// The implemented algorithm is the following.
///
/// This algorithm comes from
/// \verbatim
/// @InProceedings{ godefroid.93.pstv,
/// author = {Patrice Godefroid and Gerard .J. Holzmann},
/// title = {On the verification of temporal properties},
/// booktitle = {Proceedings of the 13th IFIP TC6/WG6.1 International
/// Symposium on Protocol Specification, Testing, and
/// Verification (PSTV'93)},
/// month = {May},
/// editor = {Andr{\'e} A. S. Danthine and Guy Leduc
/// and Pierre Wolper},
/// address = {Liege, Belgium},
/// pages = {109--124},
/// publisher = {North-Holland},
/// year = {1993},
/// series = {IFIP Transactions},
/// volume = {C-16},
/// isbn = {0-444-81648-8}
/// }
/// procedure nested_dfs ()
/// begin
/// call dfs_blue(s0);
/// end;
///
/// procedure dfs_blue (s)
/// begin
/// s.color = blue;
/// for all t in post(s) do
/// if t.color == white then
/// call dfs_blue(t);
/// end if;
/// if (the edge (s,t) is accepting) then
/// target = s;
/// call dfs_red(t);
/// end if;
/// end for;
/// end;
///
/// procedure dfs_red(s)
/// begin
/// s.color = red;
/// if s == target then
/// report cycle
/// end if;
/// for all t in post(s) do
/// if t.color != red then
/// call dfs_red(t);
/// end if;
/// end for;
/// end;
/// \endverbatim
struct magic_search : public emptiness_check
{
/// Initialize the Magic Search algorithm on the automaton \a a.
magic_search(const tgba_tba_proxy *a);
virtual ~magic_search();
///
/// It is an adaptation to TBA of the Magic Search algorithm
/// which deals with accepting states and is presented in
///
/// \verbatim
/// Article{ courcoubertis.92.fmsd,
/// author = {Costas Courcoubetis and Moshe Y. Vardi and Pierre
/// Wolper and Mihalis Yannakakis},
/// title = {Memory-Efficient Algorithm for the Verification of
/// Temporal Properties},
/// journal = {Formal Methods in System Design},
/// pages = {275--288},
/// year = {1992},
/// volume = {1}
/// }
/// \endverbatim
emptiness_check* explicit_magic_search(const tgba *a);
/// \brief Perform a Magic Search.
///
/// \return true iff the algorithm has found a new accepting
/// path.
///
/// check() can be called several times until it return false,
/// to enumerate all accepting paths.
virtual emptiness_check_result* check();
private:
// The names "stack", "h", and "x", are those used in the paper.
/// \brief Records whether a state has be seen with the magic bit
/// on or off.
struct magic
{
bool seen_without : 1;
bool seen_with : 1;
};
/// \brief A state for the spot::magic_search algorithm.
struct magic_state
{
const state* s;
bool m; ///< The state of the magic demon.
};
typedef std::pair<magic_state, tgba_succ_iterator*> state_iter_pair;
typedef std::list<state_iter_pair> stack_type;
stack_type stack; ///< Stack of visited states on the path.
typedef std::pair<bdd, bdd> tstack_item;
typedef std::list<tstack_item> tstack_type;
/// \brief Stack of transitions.
///
/// This is an addition to the data from the paper.
tstack_type tstack;
typedef Sgi::hash_map<const state*, magic,
state_ptr_hash, state_ptr_equal> hash_type;
hash_type h; ///< Map of visited states.
/// Append a new state to the current path.
void push(const state* s, bool m);
/// Check whether we already visited \a s with the Magic bit set to \a m.
bool has(const state* s, bool m) const;
const tgba_tba_proxy* a; ///< The automata to check.
/// The state for which we are currently seeking an SCC.
const state* x;
#ifndef SWIG
class result: public emptiness_check_result
{
public:
result(magic_search& ms);
virtual tgba_run* accepting_run();
private:
magic_search& ms_;
};
#endif // SWIG
};
/// \brief Returns an emptiness check on the spot::tgba automaton \a a.
///
/// \pre The automaton \a a must have at most one accepting condition (i.e.
/// it is a TBA).
///
/// The method \a check() of the returned checker can be called several times
/// (until it returns a null pointer) to enumerate all the visited accepting
/// paths. The method visits only a finite set of accepting paths.
///
/// The implemented algorithm is the following:
///
/// procedure nested_dfs ()
/// begin
/// weight = 0;
/// call dfs_blue(s0);
/// end;
///
/// procedure dfs_blue (s)
/// begin
/// s.color = cyan;
/// s.weight = weight;
/// for all t in post(s) do
/// if t.color == white then
/// if the edge (s,t) is accepting then
/// weight = weight + 1;
/// end if;
/// call dfs_blue(t);
/// if the edge (s,t) is accepting then
/// weight = weight - 1;
/// end if;
/// else if t.color == cyan and
/// (the edge (s,t) is accepting or
/// weight > t.weight) then
/// report cycle;
/// end if;
/// if the edge (s,t) is accepting then
/// call dfs_red(t);
/// end if;
/// end for;
/// s.color = blue;
/// end;
///
/// procedure dfs_red(s)
/// begin
/// if s.color == cyan then
/// report cycle;
/// end if;
/// s.color = red;
/// for all t in post(s) do
/// if t.color != red then
/// call dfs_red(t);
/// end if;
/// end for;
/// end;
///
/// It is an adaptation to TBA and an extension of the one
/// presented in
/// \verbatim
/// InProceedings{ schwoon.05.tacas,
/// author = {Stephan Schwoon and Javier Esparza},
/// title = {A Note on On-The-Fly Verification Algorithms},
/// booktitle = {TACAS'05},
/// pages = {},
/// year = {2005},
/// volume = {},
/// series = {LNCS},
/// publisher = {Springer-Verlag}
/// }
/// \endverbatim
///
/// the extention consists in the introduction of a weight associated
/// to each state in the blue stack. The weight represents the number of
/// accepting arcs traversed to reach it from the initial state.
///
emptiness_check* explicit_se05_search(const tgba *a);
}