NEWS 184 KB
Newer Older
1
New in spot 2.4.4.dev (net yet released)
2

3
4
5
6
7
8
9
10
  Build:

  - We no longuer distribute the doxygen-generated documentation in
    the tarball of Spot to save space.  This documentation is still
    available online at https://spot.lrde.epita.fr/doxygen/.  If you
    want to build a local copy you can configure Spot with
    --enable-doxygen, or simply run "cd doc && make doc".

11
12
  Tools:

13
14
15
16
  - genltl learned to generate a new family of formulas, taken from
    the SYNTCOMP competition on reactive synthesis:
    --gf-equiv=RANGE      (GFa{1} & GFa{2} & ... & GFa{n}) <-> GFz

17
18
19
20
21
22
  - genltl learned to generate 4 new families of formulas, taken
    from Müller & Sickert's GandALF'17 paper:
    --ms-example=RANGE     GF(a1&X(a2&X(a3&...)))&F(b1&F(b2&F(b3&...)))
    --ms-phi-h=RANGE       FG(a|b)|FG(!a|Xb)|FG(a|XXb)|FG(!a|XXXb)|...
    --ms-phi-r=RANGE       (FGa{n}&GFb{n})|((FGa{n-1}|GFb{n-1})&(...))
    --ms-phi-s=RANGE       (FGa{n}|GFb{n})&((FGa{n-1}&GFb{n-1})|(...))
23

24
25
26
27
  - autfilt learned --streett-like to convert an automaton in order to
    have a Streett-like acceptance condition. It only works with
    ω-automata having an acceptance in disjunctive normal form.

28
29
30
31
32
  - autfilt learned --dca to convert a Streett-like automaton or an
    automaton with an acceptance in disjunctive normal form to a
    deterministic co-Büchi automaton using the new functions
    [nsa-dnf]_to_dca() described below.

33
34
35
36
37
  - autfilt learned --acceptance-is=ACC to filter automata by
    acceptance condition.  ACC can be the name of some acceptance
    class (e.g. Büchi, Fin-less, Streett-like) or a precise acceptance
    formula in the HOA syntax.

38
39
40
41
42
43
44
45
46
  - ltlfilt learned to measure wall-time using --format=%r.

  - ltlfilt learned to measure cpu-time (as opposed to wall-time) using
    --format=%R. User or system time, for children or parent, can be
    measured separately by adding additional %[LETTER]R options.
    The difference between %r (wall-clock time) and %R (CPU time) can
    also be used to detect unreliable measurements. See
      https://spot.lrde.epita.fr/oaut.html#timing

Maximilien Colange's avatar
Maximilien Colange committed
47
48
  - ltlsynt is a new tool for synthesizing a controller from LTL/PSL
    specifications.
Thibaud Michaud's avatar
Thibaud Michaud committed
49

50
51
52
53
54
  - ltl2tgba, autfilt, and dstar2tgba have a new '--parity' option to
    force parity acceptance on the output.  Different styles can be
    requested using for instance --parity='min odd' or --parity='max
    even'.

55
56
  - ltldo learned to limit the number of automata it outputs using -n.

57
58
  - autcross, ltlcross, and ltldo learned --fail-on-timeout.

59
60
61
62
63
64
65
  - ltlcross learned --reference=COMMANDFMT to specify a translator
    that should be trusted.  Doing so makes it possible to reduce the
    number of tests to be performed, as all other translators will be
    compared to the reference's output when available.  Multiple
    reference can be given; in that case other tools are compared
    against the smallest reference automaton.

66
67
68
69
  - The new -x tls-impl=N option allows to fine-tune the
    implication-based simplification rules of ltl2tgba.  See the
    spot-x man-page for details.

70
71
72
73
74
75
76
77
78
79
80
  - The --format=%g option of tools that output automata used to
    print the acceptance condition as a *formula* in the HOA format.
    This %g can now take optional arguments to print the acceptance
    *name* in different formats.  For instance

       ... | autfilt -o '%[s]g.hoa'

    will separate a stream of automata into different files named
    by their acceptance name (Buchi, co-Buchi, Streett, etc.) or
    "other" if no name is known for the acceptance condition.

81
82
83
  - Tools that produce formulas now support --format=%[OP]n to
    display the nesting depth of operator OP.

84
85
86
87
  - All tools learned to check the SPOT_OOM_ABORT environment
    variable.  This is only useful for debuging out-of-memory
    conditions; see the spot-x(7) man page for detail.

88
89
90
91
92
  Library:

  - Rename three methods of spot::scc_info. New names are clearer. The
    old names have been deprecated.

93
94
95
96
97
98
99
  - scc_info now takes an optional argument to disable some feature
    that are expansive and not always necessary.  By default scc_info
    tracks the list of all states that belong to an SCC (you may now
    ask it not to), tracks the successor SCCs of each SCC (that can
    but turned off), and explores all SCCs of the automaton (you may
    request to stop on the first SCC that is found accepting).

100
101
102
103
104
  - The new function scc_info::states_on_acc_cycle_of() is able to
    return all states visited by any accepting cycles of the
    specified SCC. It must only be called on automata with a
    Streett-like acceptance condition.

105
106
107
108
109
  - The new function dnf_to_streett() is able to convert any automaton
    with an acceptance condition in Disjunctive Normal Form to a
    Streett-like automaton. This is used by the new option
    '--streett-like' of autfilt.

110
111
112
113
114
115
116
117
  - The new functions spot::nsa_to_[nca-dca]()
    (or spot::dnf_to_[nca-dca]()) are able to convert when possible a
    Streett-like automaton (or any automaton with an acceptance in DNF)
    to an equivalent 'nca' (nondeterministic co-Büchi automaton) or
    'dca' (deterministic co-Büchi automaton).  Actually the resulting
    automaton will always recognize at least the same language.  It can
    recognize more if the original language can not be expressed with
    a co-Büchi acceptance condition.
118

119
120
121
122
123
124
125
126
127
128
129
  - The new functions spot::is_recurrence() and spot::is_persistence()
    check respectively if a formula f belongs to the recurrence or
    persistence class. Two algorithms are available, one that
    checks if a formula is cobuchi_realizable (then it belongs to the
    persistence class) and the other that checks if it is
    detbuchi_realizable (then it belongs to the recurrence class).
    Force one method or the other by setting the environment variable
    SPOT_PR_CHECK to 1 or 2.
    Note that thanks to the duality of both classes, both algorithms
    will work either on f or its negation.
    (see https://spot.lrde.epita.fr/hierarchy.html for details).
130

131
132
133
134
135
  - A new function spot::is_obligation() can be used to test whether a
    formula is an obligation.  This is used by ltlfilt --obligation,
    and the algorithm used can be controled by the SPOT_O_CHECK
    environment variable (see the spot-x(7) man page for details).

136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
  - The new function spot::is_colored() checks if an automaton is colored
    (i.e., every transition belongs to exactly one acceptance set)

  - The new function spot::change_parity() can convert an automaton with parity
    acceptance condition to an equivalent automaton with another type of parity
    acceptance condition. The type of a parity acceptance condition states
    whether it is an odd or even parity acceptance condition, and whether it is
    a min or max parity acceptance condition.

  - The new function spot::colorize_parity() can colorize an automaton with
    a parity acceptance condition. The resulting automaton is a parity automaton
    and every transition belongs to exactly one acceptance set.

  - The new function spot::cleanup_parity_acceptance() can simplify the
    acceptance condition of an automaton with parity acceptance condition. It
    removes the unused acceptance sets and merges acceptance sets to keep the
    parity acceptance condition.

  - The new functions spot::parity_product() and spot::parity_product_or()
    compute respectively the intersection and the union of two automata with
    parity acceptance condition and keep the parity acceptance condition.

158
159
160
161
  - The new function spot::remove_univ_otf() removes universal
    transitions on the fly from an alternating Büchi automaton
    using Miyano and Hayashi's breakpoint algorithm.

162
163
164
165
166
167
168
169
  - In some cases, spot::degeneralize() would output Büchi automata
    with more SCCs than its input.  This was hard to notice, because
    very often simulation-based simplifications remove those extra
    SCCs.  This situation is now detected by spot::degeneralized() and
    fixed before returning the automaton.  A new optionnal argument
    can be passed to disable this behavior (or use -x degen-remscc=0
    from the command-line).

170
171
172
173
  - The functions for detecting stutter-invariant formulas or automata
    have been overhauled.  Their interface changed slightly.  They are
    now fully documented.

174
175
176
  - In addition to detecting stutter-invariant formulas/automata, some
    can now study a stutter-sensitive automaton and detect the subset
    of states that are stutter-invariant.  See
177
    https://spot.lrde.epita.fr/ipynb/stutter-inv.html for examples.
178

179
180
181
182
183
  - Determinization has been heavily rewritten and optimized. The algorithm has
    (almost) not changed, but it runs muuuch faster now. It also features an
    optimization for stutter-invariant automata that may produce slightly
    smaller automata.

184
185
186
187
188
  - spot::postprocessor::set_type() can now request different forms of
    parity acceptance as output.  However currently the conversions
    are not very smart: if the input does not already have parity
    acceptance, it will simply be degeneralized or determinized.

189
190
191
  - spot::remove_fin() will now call simplify_acceptance(), introduced
    in 2.4, before attempting its different Fin-removal strategies.

192
193
194
195
  - acc_cond::name(fmt) is a new method that name well-known acceptance
    conditions.   The fmt parameter specify the format to use for that
    name (e.g. to the style used in HOA, or that used by print_dot()).

196
197
198
199
200
201
202
203
204
205
  - spot::simplify_acceptance() was already merging identical acceptance
    sets, and detecting complementary sets i and j to perform the following
    simplifications
      Fin(i) & Inf(j) = Fin(i)
      Fin(i) | Inf(j) = Inf(i)
    It now additionally applies the following rules (again assuming i
    and j are complementary):
      Fin(i) & Fin(j) = f          Inf(i) | Inf(j) = t
      Fin(i) & Inf(i) = f          Fin(i) | Inf(i) = t

206
207
208
  - The new spot::formula::is_leaf() method can be used to detect
    formulas without children (atomic propositions, or constants).

209
210
211
212
  - spot::formula::map(fun) and spot::formula::traverse(fun) will
    accept additionnal arguments and pass them to fun().  See
    https://spot.lrde.epita.fr/tut03.html for some examples.

213
214
215
  - A the new function spot::nesting_depth() computes the nesting
    depth of any LTL operator.

Maximilien Colange's avatar
Maximilien Colange committed
216
217
218
219
220
221
222
223
224
  - The new function spot::print_aiger() encodes an automaton as an
    AIGER circuit and prints it. This is only possible for automata
    whose acceptance condition is trivial. It relies on a new named
    property "synthesis outputs" that describes which atomic
    propositions are to be encoded as outputs of the circuits.
    This function is used by ltlsynt to output the synthesized
    controllers in the format required by the synthesis tools
    competition SYNTCOMP.

225
226
227
  - The new function spot::check_determinism() sets both
    prop_semi_deterministic() and prop_universal() appropriately.

228
229
230
231
232
  Python:

  - The "product-states" property of automata is now accessible via
    spot.twa.get_product_states() and spot.set.get_product_states().

233
234
235
236
  - twa_word instances can be displayed as SVG pictures, with one
    signal per atomic proposition.  For some examples, see the use of
    the show() method in https://spot.lrde.epita.fr/ipynb/word.html

237
238
239
240
241
242
243
244
245
  Deprecation notices:

  (These functions still work but compilers emit warnings.)

  - spot::scc_info::used_acc(), spot::scc_info::used_acc_of() and
    spot::scc_info::acc() are deprecated. They have been renamed
    spot::scc_info::marks(), spot::scc_info::marks_of() and
    spot::scc_info::acc_sets_of() respectively.

246
247
248
249
  Backward incompatible changes:

  - The spot::closure(), spot::sl2(), spot::is_stutter_invariant()
    functions no longuer takes && arguments.  The former two have
250
251
    spot::closure_inplace() and spot::sl2_inplace() variants.  These
    functions also do not take a list of atomic propositions as an
252
253
    argument anymore.

254
255
256
257
  - The spot::bmrand() and spot::prand() functions have been removed.
    They were not used at all in Spot, and it's not Spot's objective
    to provide such random functions.

258
259
260
261
  - The spot::bdd_dict::register_all_propositions_of() function has
    been removed.  It's a low-level function was not used anywhere in
    Spot anymore, since it's better to use spot::twa::copy_ap_of().

262
263
  Bugs fixed:

264
265
266
267
  - spot::simplify_acceptance() could produce incorrect output if the
    first edge of the automaton was the only one with no acceptance
    set.  In spot 2.4.x this function was only used by autfilt
    --simplify-acceptance; in 2.5 it is now used in remove_fin().
268

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
269
New in spot 2.4.4 (2017-12-25)
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
270

271
272
273
274
275
276
  Bugs fixed:

  - The generic to_generalized_buchi() function would fail if the
    Fin-less & CNF version of the acceptance condition had several
    unit clauses.

277
278
279
280
  - If the automaton passed to sbacc() was incomplete or
    non-deterministic because of some unreachable states, then it was
    possible that the output would marked similarly while it was in
    fact complete or deterministic.
281

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
282
New in spot 2.4.3 (2017-12-19)
283

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
284
  Bugs fixed:
285
286
287
288

  - couvreur99_new() leaked memory when processing TωA that allocate
    states.

289
290
  - Some mismatched placement-new/delete reported by ASAN were fixed.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
291
292
293
294
295
296
297
  - Static compilation was broken on MinGW.

  - Execution of Jupyter notebooks from the testsuite failed with
    recent versions of Python.

  - Fix some warnings triggered by the development version of g++.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
298
299
300
301
302
New in spot 2.4.2 (2017-11-07)

  Tools:

  - ltlcross and ltldo support ltl3tela, the new name of ltl3hoa.
303

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
304
305
306
307
308
  Bugs fixed:

  - Automata produced by "genaut --ks-nca=N" were incorrectly marked
    as not complete.

309
310
311
  - Fix some cases for which the highest setting of formulas
    simplification would produce worse results than lower settings.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
312
New in spot 2.4.1 (2017-10-05)
313

314
315
  Bugs fixed:

Maximilien Colange's avatar
Typos    
Maximilien Colange committed
316
317
  - The formula class failed to build {a->c[*]} although it is
    allowed by our grammar.
318

319
320
321
322
323
324
325
326
327
328
  - spot::scc_info::determine_unknown_acceptance() incorrectly
    considered some rejecting SCC as accepting.

  - spot::streett_to_generalized_buchi() could generate automata with
    empty language if some Fin set did not intersect all accepting
    SCCs.  As a consequence, some Streett-like automata were
    considered empty even though they were not.  Also, the same
    function could crash on input that had a Streett-like acceptance
    not using all declared sets.

Maximilien Colange's avatar
Typos    
Maximilien Colange committed
329
330
331
332
  - The twa_graph::merge_edges() function relied on BDD IDs to sort
    edges.  This in turn caused some algorithms (like the
    degeneralization) to produce slighltly different (but still correct)
    outputs depending on the BDD operations performed before.
333

Maximilien Colange's avatar
Typos    
Maximilien Colange committed
334
335
  - spot::simulation() could incorrectly flag an automaton as
    non-deterministic.
336

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
337
New in spot 2.4 (2017-09-06)
338

339
340
341
342
343
344
345
346
347
348
349
  Build:

  - Spot is now built in C++14 mode, so you need at least GCC 5 or
    clang 3.4.  The current version of all major linux distributions
    ship with at least GCC 6, which defaults to C++14, so this should
    not be a problem.  In *this* release of Spot, most of the header
    files are still C++11 compatible, so you should be able to include
    Spot in a C++11 project in case you do not yet want to upgrade.
    There is also an --enable-c++17 option to configure in case you
    want to force a build of Spot in C++17 mode.

350
351
  Tools:

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
352
353
354
355
356
357
358
359
  - genaut is a new binary that produces families of automata defined
    in the literature (in the same way as we have genltl for LTL
    formulas).

  - autcross is a new binary that compares the output of tools
    transforming automata (in the same way as we have ltlcross for
    LTL translators).

360
  - genltl learned two generate two new families of formulas:
361
362
363
364
365
366
      --fxg-or=RANGE         F(p0 | XG(p1 | XG(p2 | ... XG(pn))))
      --gxf-and=RANGE        G(p0 & XF(p1 & XF(p2 & ... XF(pn))))
    The later is a generalization of --eh-pattern=9, for which a
    single state TGBA always exists (but previous version of Spot
    would build larger automata).

367
  - autfilt learned to build the union (--sum) or the intersection
Maximilien Colange's avatar
Typos    
Maximilien Colange committed
368
369
    (--sum-and) of two languages by putting two automata side-by-side
    and fiddling with the initial states.  This complements the already
370
371
    implemented intersection (--product) and union (--product-or),
    both based on a product.
372

373
  - autfilt learned to complement any alternating automaton with
374
    option --dualize.   (See spot::dualize() below.)
Thomas Medioni's avatar
Thomas Medioni committed
375

376
377
378
379
  - autfilt learned --split-edges to convert labels that are Boolean
    formulas into labels that are min-terms.  (See spot::split_edges()
    below.)

380
381
382
  - autfilt learned --simplify-acceptance to simplify some acceptance
    conditions.  (See spot::simplify_acceptance() below.)

383
384
385
386
  - autfilt --decompote-strength has been renamed to --decompose-scc
    because it can now extract the subautomaton leading to an SCC
    specified by number.  (The old name is still kept as an alias.)

387
388
389
  - The --stats=%c option of tools producing automata can now be
    restricted to count complete SCCs, using %[c]c.

390
391
392
393
394
395
  - Tools producing automata have a --stats=... option, and tools
    producing formulas have a --format=... option.  These two options
    work similarly, the use of different names is just historical.
    Starting with this release, all tools that recognize one of these
    two options also accept the other one as an alias.

396
397
  Library:

398
399
  - A new library, libspotgen, gathers all functions used to generate
    families of automata or LTL formulas, used by genltl and genaut.
400

401
  - spot::sum() and spot::sum_and() implements the union and the
402
    intersection of two automata by putting them side-by-side and
403
    using non-deterministim or universal branching on the initial
404
    state.
405

406
407
408
  - twa objects have a new property: prop_complete().  This obviously
    acts as a cache for the is_complete() function.

Maximilien Colange's avatar
Typos    
Maximilien Colange committed
409
  - spot::dualize() complements any alternating automaton.  Since
410
411
412
    the dual of a deterministic automaton is still deterministic, the
    function spot::dtwa_complement() has been deprecated and simply
    calls spot::dualize().
413

414
415
416
417
418
419
  - spot::decompose_strength() was extended and renamed to
    spot::decompose_scc() as it can now also extract a subautomaton
    leading to a particular SCC.  A demonstration of this feature via
    the Python bindings can be found at
    https://spot.lrde.epita.fr/ipynb/decompose.html

420
421
  - The print_dot() function will now display names for well known
    acceptance conditions under the formula when option 'a' is used.
422
423
    We plan to enable 'a' by default in a future release, so a new
    option 'A' has been added to hide the acceptance condition.
424

425
426
427
428
429
  - The print_dot() function has a new experimental option 'x' to
    output labels are LaTeX formulas.  This is meant to be used in
    conjunction with the dot2tex tool.  See
      https://spot.lrde.epita.fr/oaut.html#dot2tex

430
431
432
433
  - A new named property for automata called "original-states" can be
    used to record the origin of a state before transformation.  It is
    currently defined by the degeneralization algorithms, and by
    transform_accessible() and algorithms based on it (like
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
434
435
436
437
438
    remove_ap::strip(), decompose_scc()).  This is realy meant as an
    aid for writing algorithms that need this mapping, but it can also
    be used to debug these algorithms: the "original-states"
    information is displayed by the dot printer when the 'd' option is
    passed.  For instance in
439
440
441
442
443
444
445

      % ltl2tgba 'GF(a <-> Fb)' --dot=s
      % ltl2tgba 'GF(a <-> Fb)' | autfilt -B --dot=ds

    the second command outputs an automaton with states that show
    references to the first one.

446
447
448
449
  - A new named property for automata called "degen-levels" keeps track
    of the level of a state in a degeneralization. This information
    complements the one carried in "original-states".

450
451
452
453
454
  - A new named property for automata called "simulated-states" can be
    used to record the origin of a state through simulation. The
    behavior is similar to "original-states" above. Determinization
    takes advantage of this in its pretty print.

455
456
457
458
459
460
  - The new function spot::acc_cond::is_streett_like() checks whether
    an acceptance condition is conjunction of disjunctive clauses
    containing at most one Inf and at most one Fin.  It builds a
    vector of pairs to use if we want to assume the automaton has
    Streett acceptance.  The dual function is
    spot::acc_cond::is_rabin_like() works similarly.
461

462
463
464
465
466
  - The degeneralize() function has learned to consider acceptance
    marks common to all edges comming to a state to select its initial
    level.  A similar trick was already used in sbacc(), and saves a
    few states in some cases.

467
468
469
470
471
472
473
  - There is a new spot::split_edges() function that transforms edges
    (labeled by Boolean formulas over atomic propositions) into
    transitions (labeled by conjunctions where each atomic proposition
    appear either positive or negative).  This can be used to
    preprocess automata before feeding them to algorithms or tools
    that expect transitions labeled by letters.

474
475
476
  - spot::scc_info has two new methods to easily iterate over the
    edges of an SCC: edges_of() and inner_edges_of().

477
478
479
  - spot::scc_info can now be passed a filter function to ignore
    or cut some edges.

480
481
482
483
484
  - spot::scc_info now keeps track of acceptance sets that are common
    to all edges in an SCC.  These can be retrieved using
    scc_info::common_sets_of(scc), and they are used by scc_info to
    classify some SCCs as rejecting more easily.

485
486
487
488
489
490
  - The new function acc_code::remove() removes all the given
    acceptance sets from the acceptance condition.

  - It is now possible to change an automaton acceptance condition
    directly by calling twa::set_acceptance().

491
492
493
494
495
  - spot::cleanup_acceptance_here now takes an additional boolean
    parameter specifying whether to strip useless marks from the
    automaton.  This parameter is defaulted to true, in order to
    keep this modification backward-compatible.

496
497
498
499
  - The new function spot::simplify_acceptance() is able to perform
    some simplifications on an acceptance condition, and might lead
    to the removal of some acceptance sets.

500
  - The function spot::streett_to_generalized_buchi() is now able to
501
    work on automata with Streett-like acceptance.
502

503
504
505
506
507
  - The function for converting deterministic Rabin automata to
    deterministic Büchi automata (when possible), internal to the
    remove_fin() procedure, has been updated to work with
    transition-based acceptance and with Rabin-like acceptance.

508
509
510
511
  - spot::relabel_here() was used on automata to rename atomic
    propositions, it can now replace atomic propositions by Boolean
    subformula.  This makes it possible to use relabeling maps
    produced by relabel_bse() on formulas.
512

513
514
515
516
  - twa_graph::copy_state_names_from() can be used to copy the state
    names from another automaton, honoring "original-states" if
    present.

517
518
  - Building automata for LTL formula with a large number N of atomic
    propositions can be costly, because several loops and
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
519
    data-structures are exponential in N.  However a formula like
520
521
522
523
524
525
526
527
      ((a & b & c) | (d & e & f)) U ((d & e & f) | (g & h & i))
    can be translated more efficiently by first building an automaton
    for (p0 | p1) U (p1 | p2), and then substituting p0, p1, p2 by the
    appropriate Boolean formula.  Such a trick is now attempted
    for translation of formulas with 4 atomic propositions or
    more (this threshold can be changed, see -x relabel-bool=N in
    the spot-x(7) man page).

528
529
530
531
  - The LTL simplification routines learned that an LTL formula like
    G(a & XF(b & XFc & Fd) can be simplified to G(a & Fb & Fc & Fd),
    and dually F(a | XG(b | XGc | Gd)) = F(a | Gb | Gc | Gd).

532
533
534
535
    When working with SERE, the simplification of "expr[*0..1]" was
    improved.  E.g. {{a[*]|b}[*0..1]} becomes {a[*]|b} instead of
    {{a[+]|b}[*0..1]}.

536
537
538
539
  - The new function spot::to_weak_alternating() is able to take an
    input automaton with generalized Büchi/co-Büchi acceptance and
    convert it to a weak alternating automaton.

540
541
  - spot::sbacc() is can now also convert alternating automata
    to state-based acceptance.
542

543
544
545
  - spot::sbacc() and spot::degeneralize() learned to merge
    accepting sinks.

546
  - If the SPOT_BDD_TRACE environment variable is set, statistics
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
547
548
    about BDD garbage collection and table resizing are shown.

549
  - The & and | operators for acceptannce conditions have been changed
550
    slightly to be more symmetrical.  In older versions, operator &
551
552
553
554
    would move Fin() terms to the front, but that is not the case
    anymore.  Also operator & was already grouping all Inf() terms
    (for efficiency reasons), in this version operator | is
    symmetrically grouping all Fin() terms.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
555

556
557
558
559
  - The automaton parser is now reentrant, making it possible to
    process automata from different streams at the same time (i.e.,
    using multiple spot::automaton_stream_parser instances at once).

560
561
562
563
564
565
566
567
568
  - The print_hoa() and parse_automaton() functions have been updated
    to recognize the "exist-branch" property of the non-released HOA
    v1.1, as well as the new meaning of property "deterministic".  (In
    HOA v1 "properties: deterministic" means that the automaton has no
    existential branching; in HOA v1.1 it disallows universal
    branching as well.)  The meaning of "deterministic" in Spot has
    been adjusted to these new semantics, see "Backward-incompatible
    changes" below.

Maximilien Colange's avatar
Typos    
Maximilien Colange committed
569
  - The parser for HOA now recognizes and verifies correct use of the
570
    "univ-branch" property.  This is known to be a problem with option
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
571
    -H1 of ltl3ba 1.1.2 and ltl3dra 0.2.4, so the environment variable
572
573
    SPOT_HOA_TOLERANT can be set to disable the diagnostic.

574
575
576
577
578
  Python:

  - The 'spot.gen' package exports the functions from libspotgen.
    See https://spot.lrde.epita.fr/ipynb/gen.html for examples.

579
580
581
582
  Bugs fixed:

  - When the remove_fin() function was called on some automaton with
    Inf-less acceptance involving at least one disjunction (e.g.,
Maximilien Colange's avatar
Typos    
Maximilien Colange committed
583
    generalized co-Büchi), it would sometimes output an automaton with
584
585
    transition-based acceptance but marked as state-based.

586
587
  - The complete() function could complete an empty co-Büchi automaton
    into an automaton accepting everything.
588

589
590
591
592
593
594
595
596
597
598
  Backward-incompatible changes:

  - spot::acc_cond::mark_t::operator bool() has been marked as
    explicit.  The implicit converion to bool (and, via bool, to int)
    was a source of bugs.

  - spot::twa_graph::set_init_state(const state*) has been removed.
    It was never used.  You always want to use
    spot::twa_graph::set_init_state(unsigned) in practice.

599
600
601
602
603
604
605
  - The previous implementation of spot::is_deterministic() has been
    renamed to spot::is_universal().  The new version of
    spot::is_deterministic() requires the automaton to be both
    universal and existential.  This should not make any difference in
    existing code unless you work with the recently added support for
    alternating automata.

606
607
608
  - spot::acc_cond::mark_t::sets() now returns an internal iterable
    object instead of an std::vector<unsigned>.

609
610
611
612
  - The color palette optionally used by print_dot() has been extended
    from 9 to 16 colors.  While the first 8 colors are similar, they
    are a bit more saturated now.

613
  deprecation notices:
614

615
  (these functions still work but compilers emit warnings.)
616

617
618
619
  - spot::decompose_strength() is deprecated, it has been renamed
    to spot::decompose_scc().

620
  - spot::dtwa_complement() is deprecated.  prefer the more generic
621
622
    spot::dualize() instead.

623
  - the spot::twa::prop_deterministic() methods have been renamed to
624
    spot::twa::prop_universal() for consistency with the change to
625
    is_deterministic() listed above.  we have kept
626
627
    spot::twa::prop_deterministic() as a deprecated synonym for
    spot::twa::prop_universal() to help backward compatibility.
628

629
  - the spot::copy() function is deprecated.  use
630
631
    spot::make_twa_graph() instead.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
632
New in spot 2.3.5 (2017-06-22)
633

634
635
  Bugs fixed:

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
636
  - We have fixed new cases where translating multiple formulas in a
637
638
    single ltl2tgba run could produce automata different from those
    produced by individual runs.
639

640
641
642
643
644
  - The print_dot() function had a couple of issues when printing
    alternating automata: in particular, when using flag 's' (display
    SCC) or 'y' (split universal destination by colors) universal
    edges could be connected to undefined states.

645
646
647
648
649
650
  - Using --stats=%s or --stats=%s or --stats=%t could take an
    unnecessary long time on automata with many atomic propositions,
    due to a typo.  Furthermore, %s/%e/%t/%E/%T were printing
    a number of reachable states/edges/transitions, but %S was
    incorrectly counting all states even unreachable.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
651
652
653
  - Our verson of BuDDy had an incorrect optimization for the
    biimp operator.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
654
New in spot 2.3.4 (2017-05-11)
655

656
657
  Bugs fixed:

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
658
  - The transformation to state-based acceptance (spot::sbacc()) was
659
    incorrect on automata where the empty acceptance mark is accepting.
660

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
661
  - The --help output of randaut and ltl2tgba was showing an
662
663
    unsupported %b stat.

664
665
666
  - ltldo and ltlcross could leave temporary files behind when
    aborting on error.

667
668
669
670
  - The LTL simplifcation rule that turns F(f)|q into F(f|q)
    when q is a subformula that is both eventual and universal
    was documented but not applied in some forgotten cases.

671
672
673
674
  - Because of some caching inside of ltl2tgba, translating multiple
    formula in single ltl2tgba run could produce automata different
    from those produced by individual runs.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
675
New in spot 2.3.3 (2017-04-11)
676

677
678
679
680
681
  Tools:

  - ltldo and ltlcross learned shorthands to talk to ltl2da, ltl2dpa,
    and ltl2ldba (from Owl) without needing to specify %f>%O.

682
  - genltl learned --spec-patterns as an alias for --dac-patterns; it
683
684
685
    also learned two new sets of LTL formulas under --hkrss-patterns
    (a.k.a. --liberouter-patterns) and --p-patterns
    (a.k.a. --beem-patterns).
686

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
687
  Bugs fixed:
688

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
689
690
  - In "lenient" mode the formula parser would fail to recover from a
    missing closing brace.
691

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
692
693
  - The output of 'genltl --r-left=1 --r-right=1 --format=%F' had
    typos.
694

695
696
697
698
  - 'ltl2tgba Fa | autfilt --complement' would incorrectly claim that
    the output is "terminal" because dtwa_complement() failed to reset
    that property.

699
700
701
  - spot::twa_graph::purge_unreachable_states() was misbehaving on
    alternating automata.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
702
703
  - In bench/stutter/ the .cc files were not compiling due to warnings
    being caught as errors.
704

705
706
707
708
709
710
  - The code in charge of detecting DBA-type Rabin automata is
    actually written to handle a slightly larger class of acceptance
    conditions (e.g., Fin(0)|(Fin(1)&Inf(2))), however it failed to
    correctly detect DBA-typeness in some of these non-Rabin
    acceptance.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
711
New in spot 2.3.2 (2017-03-15)
712

713
714
  Tools:

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
715
  - In tools that output automata, the number of atomic propositions
716
    can be output using --stats=%x (output automaton) or --stats=%X
717
    (input automaton).  Additional options can be passed to list
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
718
    atomic propositions instead of counting them.  Tools that output
719
    formulas also support --format=%x for this purpose.
720

721
722
  Python:

723
724
  - The bdd_to_formula(), and to_generalized_buchi() functions can now
    be called in Python.
725

726
727
728
729
730
  Documentation:

  - https://spot.lrde.epita.fr/tut11.html is a new page describing
    how to build monitors in Shell, Python, or C++.

731
732
733
734
735
  Bugs fixed:

  - The tests using LTSmin's patched version of divine would fail
    if the current (non-patched) version of divine was installed.

736
737
738
  - Because of a typo, the output of --stats='...%P...' was correct
    only if %p was used as well.

739
740
741
  - genltl was never meant to have (randomly attributed) short
    options for --postive and --negative.

742
743
744
745
  - a typo in the code for transformating transition-based acceptance
    to state-based acceptance could cause a superfluous initial state
    to be output in some cases (the result was still correct).

746
747
  - 'ltl2tgba --any -C -M ...' would not complete automata.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
748
  - While not incorrect, the HOA properties output by 'ltl2tgba -M'
749
750
751
752
    could be 'inherently-weak' or 'terminal', while 'ltl2tgba -M -D'
    would always report 'weak' automata.  Both variants now report the
    most precise between 'weak' or 'terminal'.

753
754
755
  - spot::twa_graph::set_univ_init_state() could not be called with
    an initializer list.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
756
  - The Python wrappers for spot::twa_graph::state_from_number and
757
758
    spot::twa_graph::state_acc_sets were broken in 2.3.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
759
  - Instantiating an emptiness check on an automaton with unsupported
760
761
762
763
    acceptance condition should throw an exception.  This used to be
    just an assertion, disabled in release builds; the difference
    matters for the Python bindings.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
764
  Deprecation notice:
765
766
767
768

  - Using --format=%a to print the number of atomic propositions in
    ltlfilt, genltl, and randltl still works, but it is not documented
    anymore and should be replaced by the newly-introduced --format=%x
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
769
770
    for consistency with tools producing automata, where %a means
    something else.
771

772

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
773
New in spot 2.3.1 (2017-02-20)
774

775
776
777
778
779
780
  Tools:

  - ltldo learnt to act like a portfolio: --smallest and --greatest
    will select the best output automaton for each formula translated.
    See https://spot.lrde.epita.fr/ltldo.html#portfolio for examples.

781
782
783
  - The colors used in the output of ltlcross have been adjusted to
    work better with white backgrounds and black backgrounds.

784
785
786
  - The option (y) has been added to --dot. It splits the universal
    edges with the same targets but different colors.

787
788
789
790
791
  - genltl learnt three new families for formulas: --kr-n2=RANGE,
    --kr-nlogn=RANGE, and --kr-n=RANGE.  These formulas, from
    Kupferman & Rosenberg [MoChArt'10] are recognizable by
    deterministic Büchi automata with at least 2^2^n states.

792
793
794
795
  Library:

  - spot::twa_run::as_twa() has an option to preserve state names.

796
797
798
799
  - the method spot::twa::is_alternating(), introduced in Spot 2.3 was
    badly named and has been deprecated.  Use the negation of the new
    spot::twa::is_existential() instead.

800
801
802
803
804
805
806
  Bugs fixed:

  - spot::otf_product() was incorrectly registering atomic
    propositions.

  - spot::ltsmin_model::kripke() forgot to register the "dead"
    proposition.
807

808
809
810
811
812
813
  - The spot::acc_word type (used to construct acceptance condition)
    was using some non-standard anonymous struct.  It is unlikely that
    this type was actually used outside Spot, but if you do use it,
    spot::acc_word::op and spot::acc_word::type had to be renamed as
    spot::acc_word::sub.op and spot::acc_word::sub.type.

814
815
816
  - alternation_removal() was not always reporting the unsupported
    non-weak automata.

817
818
819
820
  - a long-standing typo in the configure code checking for Python
    caused any user-defined CPPFLAGS to be ignored while building
    Spot.

821
822
823
824
  - The display of clusters with universal edges was confused, because the
    intermediate node was not in the cluster even if one of the target was
    in the same one.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
825
New in spot 2.3 (2017-01-19)
826

827
828
829
830
831
832
833
834
835
836
837
  Build:

  * While Spot only relies on C++11 features, the configure script
    learned --enable-c++14 to compile in C++14 mode.  This allows us
    check that nothing breaks when we will switch to C++14.

  * Spot is now distributed with PicoSAT 965, and uses it for
    SAT-based minimization of automata without relying on temporary
    files.  It is still possible to use an external SAT solver by
    setting the SPOT_SATSOLVER environment variable.

838
839
840
  * The development Debian packages for Spot now install static
    libraries as well.

841
842
  * We now install configuration files for users of pkg-config.

843
844
  Tools:

845
846
847
  * ltlcross supports translators that output alternating automata in
    the HOA format.  Cross-comparison checks will only work with weak
    alternating automata (not necessarily *very* weak), but "ltlcross
848
849
    --no-check --product=0 --csv=..." will work with any alternating
    automaton if you just want satistics.
850

851
852
853
854
855
856
  * autfilt can read alternating automata.  This is still experimental
    (see below). Some of the algorithms proposed by autfilt will
    refuse to work because they have not yet been updated to work with
    alternating automata, but in any case they should display a
    diagnostic: if you see a crash, please report it.

857
858
859
  * autfilt has three new filters: --is-very-weak, --is-alternating,
    and --is-semi-deterministic.

860
861
  * the --check option of autfilt/ltl2tgba/ltldo/dstar2tgba can now
    take "semi-determinism" as argument.
862

863
  * autfilt --highlight-languages will color states that recognize
864
    identical languages.  (Only works for deterministic automata.)
865

866
867
868
869
870
  * 'autfilt --sat-minimize' and 'ltl2tgba -x sat-minimize' have
    undergone some backward incompatible changes.  They use binary
    search by default, and support different options than they used
    too.  See spot-x(7) for details.  The defaults are those that were
    best for the benchmark in bench/dtgbasat/.
871

872
873
874
875
  * ltlfilt learned --recurrence and --persistence to match formulas
    belonging to these two classes of the temporal hierarchy.  Unlike
    --syntactic-recurrence and --syntactic-persistence, the new checks
    are automata-based and will also match pathological formulas.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
876
    See https://spot.lrde.epita.fr/hierarchy.html
877

878
  * The --format option of ltlfilt/genltl/randltl/ltlgrind learned to
879
    print the class of a formula in the temporal hierarchy of Manna &
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
880
    Pnueli using %h.  See https://spot.lrde.epita.fr/hierarchy.html
881

882
883
884
885
886
887
  * ltldo and ltlcross learned a --relabel option to force the
    relabeling of atomic propositions to p0, p1, etc.  This is more
    useful with ltldo, as it allows calling a tool that restricts the
    atomic propositions it supports, and the output automaton will
    then be fixed to use the original atomic propositions.

888
889
890
  * ltldo and ltlcross have learned how to call ltl3hoa, so
    'ltl3hoa -f %f>%O' can be abbreviated to just 'ltl3hoa'.

891
892
893
  Library:

  * A twa is required to have at least one state, the initial state.
894
895
    An automaton can only be empty while it is being constructed,
    but should not be passed to other algorithms.
896

897
  * Couvreur's emptiness check has been rewritten to use the explicit
898
899
    interface when possible, to avoid overkill memory allocations.
    The new version has further optimizations for weak and terminal
900
901
902
    automata.  Overall, this new version is roughly 4x faster on
    explicit automata than the former one.  The old version has been
    kept for backward compatibility, but will be removed eventually.
903

904
  * The new version of the Couvreur emptiness check is now the default
905
906
    one, used by twa::is_empty() and twa::accepting_run().  Always
    prefer these functions over an explicit call to Couvreur.
907

908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
  * experimental support for alternating automata:

    - twa_graph objects can now represent alternating automata.  Use
      twa_graph::new_univ_edge() and twa_graph::set_univ_init_state()
      to create universal edges an initial states; and use
      twa_graph::univ_dests() to iterate over the universal
      destinations of an edge.

    - the automaton parser will now read alternating automata in the
      HOA format.  The HOA and dot printers can output them.

    - the file twaalgos/alternation.hh contains a few algorithms
      specific to alternating automata:
      + remove_alternation() will transform *weak* alternating automata
        into TGBA.
      + the class outedge_combiner can be used to perform "and" and "or"
        on the outgoing edges of some alternating automaton.

926
    - scc_info has been adjusted to handle universal edges as if they
927
928
929
      were existential edges.  As a consequence, acceptance
      information is not accurate.

930
931
932
933
934
935
936
    - postprocessor will call remove_alternation() right away, so
      it can be used as a way to transform alternating automata
      into different sub-types of (generalized) Büchi automata.
      Note that although prostprocessor optimize the resulting
      automata, it still has no simplification algorithms that work
      at the alternating automaton level.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
937
938
939
    - See https://spot.lrde.epita.fr/tut23.html
      https://spot.lrde.epita.fr/tut24.html and
      https://spot.lrde.epita.fr/tut31.html for some code examples.
940

941
942
943
944
  * twa objects have two new properties, very-weak and
    semi-deterministic, that can be set or retrieved via
    twa::prop_very_weak()/twa::prop_semi_deterministic(), and that can
    be tested by is_very_weak_automaton()/is_semi_deterministic().
945

946
947
948
949
950
951
  * twa::prop_set has a new attribute used in twa::prop_copy() and
    twa::prop_keep() to indicate that determinism may be improved by
    an algorithm.  In other words properties like
    deterministic/semi-deterministic/unambiguous should be preserved
    only if they are positive.

952
  * language_map() and highlight_languages() are new functions that
953
    implement autfilt's --highlight-languages option mentionned above.
954

955
  * dtgba_sat_minimize_dichotomy() and dwba_sat_minimize_dichotomy()
956
    use language_map() to estimate a lower bound for binary search.
957

958
  * The encoding part of SAT-based minimization consumes less memory.
959

960
961
962
963
  * SAT-based minimization of automata can now be done using two
    incremental techniques that take a solved minimization and attempt
    to forbid the use of some states.  This is done either by adding
    clauses, or by using assumptions.
964

965
966
967
968
  * If the environment variable "SPOT_XCNF" is set during incremental
    SAT-based minimization, XCNF files suitable for the incremental SAT
    competition will be generated.  This requires the use of an exteral
    SAT solver, setup with "SPOT_SATSOLVER".  See spot-x(7).
969

970
971
972
  * The new function mp_class(f) returns the class of the formula
    f in the temporal hierarchy of Manna & Pnueli.

973
974
975
976
977
978
979
980
981
Python:

  * spot.show_mp_hierarchy() can be used to display the membership of
    a formula to the Manna & Pnueli hierarchy, in notebooks.  An
    example is in https://spot.lrde.epita.fr/ipynb/formulas.html

  * The on-line translator will now display the temporal hierarchy
    in the "Formula > property information" output.

982
Bugs fixed:
983
984
985
986
987
988
989
990

  * The minimize_wdba() function was not correctly minimizing automata
    with useless SCCs.  This was not an issue for the LTL translation
    (where useless SCCs are always removed first), but it was an issue
    when deciding if a formula was safety or guarantee.  As a
    consequence, some tricky safety or guarantee properties were only
    recognized as obligations.

991
992
993
994
  * When ltlcross was running a translator taking the Spin syntax as
    input (%s) it would not automatically relabel any unsupported
    atomic propositions as ltldo already do.

995
996
997
998
  * When running "autfilt --sat-minimize" on a automaton representing
    an obligation property, the result would always be a complete
    automaton even without the -C option.

999
1000
1001
  * ltlcross --products=0 --csv should not output any product-related
    column in the CSV output since it has nothing to display there.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1002
New in spot 2.2.2 (2016-12-16)
1003

1004
1005
1006
1007
1008
  Build:

  * If the system has an installed libltdl library, use it instead of
    the one we distribute.

1009
1010
1011
1012
  Bug fixes:

  * scc_filter() had a left-over print statement that would print
    "names" when copying the name of the states.
1013

1014
1015
1016
1017
1018
  * is_terminal() should reject automata that have accepting
    transitions going into rejecting SCCs.  The whole point of
    being a terminal automaton is that reaching an accepting
    transition guarantees that any suffix will be accepted.

1019
1020
1021
1022
1023
  * The HOA parser incorrectly read "Acceptance: 1 Bar(0)" as a valid
    way to specify "Acceptance: 1 Fin(0)" because it assumed that
    everything that was not Inf was Fin.  These errors are now
    diagnosed.

1024
1025
1026
1027
  * Some of the installed headers (spot/misc/fixpool.hh,
    spot/misc/mspool.hh, spot/twaalgos/emptiness_stats.hh) were not
    self-contained.

1028
1029
1030
  * ltlfilt --from-ltlf should ensure that "alive" holds initially in
    order to reject empty traces.

1031
1032
1033
  * the on-line translator had a bug where a long ltl3ba process would
    continue running even after the script had timeout'ed.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1034
New in spot 2.2.1 (2016-11-21)
1035

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1036
  Bug fix:
1037

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1038
1039
  * The bdd_noderesize() function, as modified in 2.2, would always
    crash.
1040

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1041
New in spot 2.2 (2016-11-14)
1042

1043
1044
1045
1046
1047
1048
  Command-line tools:

  * ltlfilt has a new option --from-ltlf to help reducing LTLf (i.e.,
    LTL over finite words) model checking to LTL model checking.  This
    is based on a transformation by De Giacomo & Vardi (IJCAI'13).

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1049
1050
1051
1052
  * "ltldo --stats=%R", which used to display the serial number of the
    formula processed, was renamed to "ltldo --stats=%#" to free %R
    for the following feature.

1053
1054
1055
  * autfilt, dstar2tgba, ltl2tgba, ltlcross, ltldo learned to measure
    cpu-time (as opposed to wall-time) using --stats=%R.  User or
    system time, for children or parent, can be measured separately by
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1056
1057
1058
1059
    adding additional %[LETTER]R options.  The difference between %r
    (wall-clock time) and %R (CPU time) can also be used to detect
    unreliable measurements.  See
      https://spot.lrde.epita.fr/oaut.html#timing
1060

1061
1062
  Library:

1063
1064
1065
  * from_ltlf() is a new function implementing the --from-ltlf
    transformation described above.

1066
  * is_unambiguous() was rewritten in a more efficient way.
1067

1068
  * scc_info learned to determine the acceptance of simple SCCs made
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1069
    of a single self-loop without resorting to remove_fin() for complex
1070
1071
1072
1073
1074
1075
    acceptance conditions.

  * remove_fin() has been improved to better deal with automata with
    "unclean" acceptance, i.e., acceptance sets that are declared but
    not used.  In particular, this helps scc_info to be more efficient
    at deciding the acceptance of SCCs in presence of Fin acceptance.
1076

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1077
1078
  * Simulation-based reductions now implement just bisimulation-based
    reductions on deterministic automata, to save time.  As an example,
1079
1080
1081
    this halves the run time of
       genltl --rv-counter=10 | ltl2tgba

1082
1083
  * scc_filter() learned to preserve state names and highlighted states.

1084
1085
1086
1087
1088
  * The BuDDy library has been slightly optimized: the initial setup
    of the unicity table can now be vectorized by GCC, and all calls
    to setjmp are now avoided when variable reordering is disabled
    (the default).

1089
1090
1091
1092
1093
1094
1095
1096
  * The twa class has three new methods:
      aut->intersects(other)
      aut->intersecting_run(other)
      aut->intersecting_word(other)
    currently these are just convenient wrappers around
      !otf_product(aut, other)->is_empty()
      otf_product(aut, other)->accepting_run()->project(aut)
      otf_product(aut, other)->accepting_word()
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1097
1098
1099
    with any Fin-acceptance removal performed before the product.
    However the plan is to implement these more efficiently in the
    future.
1100

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1101
  Bug fixes:
1102

1103
  * ltl2tgba was always using the highest settings for the LTL
1104
1105
1106
1107
    simplifier, ignoring the --low and --medium options.  Now
      genltl --go-theta=12 | ltl2tgba --low --any
    is instantaneous as it should be.

1108
1109
1110
  * The int-vector compression code could encode 6 and 22 in the
    same way, causing inevitable issues in our LTSmin interface.
    (This affects tests/ltsmin/modelcheck with option -z, not -Z.)
1111

1112
1113
1114
  * str_sere() and str_utf8_sere() were not returning the same
    string that print_sere() and print_utf8_sere() would print.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1115
  * Running the LTL parser in debug mode would crash.
1116

1117
  * tgba_determinize() could produce incorrect deterministic automata
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1118
    when run with use_simulation=true (the default) on non-simplified
1119
1120
    automata.

1121
1122
  * When the automaton_stream_parser reads an automaton from an
    already opened file descriptor, it will not close the file
1123
1124
1125
1126
    anymore.  Before that the spot.automata() python function used to
    close a file descriptor twice when reading from a pipe, and this
    led to crashes of the 0MQ library used by Jupyter, killing the
    Python kernel.
1127

1128
1129
1130
  * remove_fin() could produce incorrect result on incomplete
    automata tagged as weak and deterministic.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1131
1132
1133
  * calling set_acceptance() several times on an automaton could
    result in unexpected behaviors, because set_acceptance(0,...)
    used to set the state-based acceptance flag automatically.
1134

1135
  * Some buffering issue caused syntax errors to be displayed out
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1136
    of place by the on-line translator.
1137

1138
New in spot 2.1.2 (2016-10-14)
1139

1140
1141
1142
1143
1144
1145
  Command-line tools:

  * genltl learned 5 new families of formulas
    (--tv-f1, --tv-f2, --tv-g1, --tv-g2, --tv-uu)
    defined in Tabakov & Vardi's RV'10 paper.

1146
1147
1148
1149
1150
1151
  * ltlcross's --csv and --json output was changed to not include
    information about the ambiguity or strength of the automata by
    default.   Computing those can be costly and not needed by
    every user, so it should now be requested explicitely using
    options --strength and --ambiguous.

1152
1153
1154
1155
1156
1157
1158
1159
  Library:

  * New LTL simplification rule:

    - GF(f & q) = G(F(f) & q) if q is
      purely universal and a pure eventuality.  In particular
      GF(f & GF(g)) now ultimately simplifies to G(F(f) & F(g)).

1160
1161
  Bug fixes:

1162
  * Fix spurious uninitialized read reported by valgrind when
1163
    is_Kleene_star() is compiled by clang++.
1164

1165
  * Using "ltlfilt some-large-file --some-costly-filter" could take
1166
1167
1168
1169
1170
1171
1172
    to a lot of time before displaying the first results, because the
    output of ltlfilt is buffered: the buffer had to fill up before
    being flushed.  The issue did not manifest when the input is
    standard input, because of the C++ feature that reading std::cin
    should flush std::cout; however it was well visible when reading
    from files.  Flushing is now done more regularly.

1173
1174
1175
1176
  * Fix compilation warnings when -Wimplicit-fallthrough it enabled.

  * Fix python errors on Darwin when using methods from the spot module
    inside of the spot.ltsmin submodule.
1177

1178
1179
  * Fix ltlcross crash when combining --no-check with --verbose.

1180
1181
1182
  * Adjust paths and options used in bench/dtgbasat/ to match the
    changes introduced in Spot 2.0.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1183
New in spot 2.1.1 (2016-09-20)
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1184

1185
1186
1187
  Command-line tools:

  * ltlfilt, randltl, genltl, and ltlgrind learned to display the size
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1188
    (%s), Boolean size (%b), and number of atomic propositions (%a)
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1189
1190
    with the --format and --output options.  A typical use-case is to
    sort formulas by size:
1191
1192
1193
1194
       genltl --dac --format='%s,%f' | sort -n | cut -d, -f2
    or to group formulas by number of atomic propositions:
       genltl --dac --output='ap-%a.ltl'

1195
1196
1197
  * autfilt --stats learned the missing %D, %N, %P, and %W sequences,
    to complete the existing %d, %n, %p, and %w.

1198
  * The --stats %c option of ltl2tgba, autfilt, ltldo, and dstar2tgba
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1199
    now accepts options to filter the SCCs to count.  For instance
1200
1201
1202
    --stats='%[awT]c' will count the SCCs that are (a)ccepting and
    (w)eak, but (not t)erminal.  See --help for all supported filters.

1203
1204
1205
  Bugs fixed:

  * Fix several cases where command-line tools would fail to diagnose
1206
    write errors (e.g. when writing to a filesystem that is full).
1207
  * Typos in genltl --help and in the man page spot-x(7).
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1208

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1209
New in spot 2.1 (2016-08-08)
1210

1211
1212
  Command-line tools:

1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
  * All tools that input formulas or automata (i.e., autfilt,
    dstar2tgba, ltl2tgba, ltl2tgta, ltlcross, ltldo, ltlfilt,
    ltlgrind) now have a more homogeneous handling of the default
    input.

    - If no formula/automaton have been specified, and the standard
    input is a not a tty, then the default is to read that. This is a
    change for ltl2tgba and ltl2tgta.  In particular, it simplifies

        genltl --dac | ltl2tgba -F- | autfilt ...

    into

        genltl --dac | ltl2tgba | autfilt ...

    - If standard input is a tty and no other input has been
    specified, then an error message is printed.  This is a change for
    autfilt, dstar2tgba, ltlcross, ltldo, ltlfilt, ltlgrind, that used
    to expect the user to type formula or automata at the terminal,
    confusing people.

    - All tools now accept - as a shorthand for -F-, to force reading
    input from the standard input (regardless of whether it is a tty
    or not).  This is a change for ltl2tgba, ltl2tgta, ltlcross, and
    ltldo.

1239
1240
1241
  * ltldo has a new option --errors=... to specify how to deal
    with errors from executed tools.

1242
1243
  * ltlcross and ltldo learned to bypass the shell when executing
    simple commands (with support for single or double-quoted
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
    arguments, and redirection of stdin and stdout, but nothing more).

  * ltlcross and ltldo learned a new syntax to specify that an input
    formula should be written in some given syntax after rewriting
    some operators away.  For instance the defaults arguments passed
    to ltl2dstar have been changed from
         --output-format=hoa %L %O
    into
         --output-format=hoa %[WM]L %O
    where [WM] specifies that operators W and M should be rewritten
    away.  As a consequence running
         ltldo ltl2dstar -f 'a M b'
    will now work and call ltl2dstar on the equivalent formula
    'b U (a & b)' instead.  The operators that can be listed between
    brackets are the same as those of ltlfilt --unabbreviate option.

  * ltlcross learned to show some counterexamples when diagnosing
    failures of cross-comparison checks against random state spaces.
1262

1263
1264
  * autfilt learned to filter automata by count of SCCs (--sccs=RANGE)
    or by type of SCCs (--accepting-sccs=RANGE,
1265
1266
1267
    --rejecting-sccs=RANGE, trivial-sccs=RANGE, --terminal-sccs=RANGE,
    --weak-sccs=RANGE, --inherently-weak-sccs=RANGE).

1268
  * autfilt learned --remove-unused-ap to remove atomic propositions
1269
1270
    that are declared in the input automaton, but not actually used.
    This of course makes sense only for input/output formats that
1271
    declare atomic propositions (HOA & DSTAR).
1272

1273
  * autfilt learned two options to filter automata by count of used or
1274
1275
1276
1277
    unused atomic propositions: --used-ap=RANGE --unused-ap=RANGE.
    These differ from --ap=RANGE that only consider *declared* atomic
    propositions, regardless of whether they are actually used.

1278
1279
  * autfilt learned to filter automata by count of nondeterministsic
    states with --nondet-states=RANGE.
1280

1281
  * autfilt learned to filter automata representing stutter-invariant
1282
1283
    properties with --is-stutter-invariant.

1284
  * autfilt learned two new options to highlight non-determinism:
1285
    --highlight-nondet-states=NUM and --highlight-nondet-states=NUM
1286
1287
    where NUM is a color number.  Additionally --highlight-nondet=NUM is
    a shorthand for using the two.
1288

1289
  * autfilt learned to highlight a run matching a given word using the
1290
1291
1292
    --highlight-word=[NUM,]WORD option.  However currently this only
    work on automata with Fin-less acceptance.

1293
1294
1295
  * autfilt learned two options --generalized-rabin and
    --generalized-streett to convert the acceptance conditions.

1296
  * genltl learned three new families: --dac-patterns=1..45,
1297
1298
1299
    --eh-patterns=1..12, and --sb-patterns=1..27.  Unlike other options
    these do not output scalable patterns, but simply a list of formulas
    appearing in these three papers: Dwyer et al (FMSP'98), Etessami &
1300
    Holzmann (Concur'00), Somenzi & Bloem (CAV'00).
1301