1		% (c) 2009-2025 Lehrstuhl fuer Softwaretechnik und Programmiersprachen,
2		% Heinrich Heine Universitaet Duesseldorf
3		% This software is licenced under EPL 1.0 (http://www.eclipse.org/org/documents/epl-v10.html)
4
5		:- module(state_space,
6		[get_state_space_stats/3, get_state_space_stats/4,
7		gen_new_state_id/1,
8		history/1, forward_history/1,
9		get_action_trace/1, % old trace/1
10		get_action_trace_with_limit/2,
11		get_action_term_trace/1,
12		op_trace_ids/1, add_to_op_trace_ids/1, remove_from_op_trace_ids/1, reset_op_trace_ids/0,
13		get_state_id_trace/1,
14		current_state_id/1, current_expression/2,
15		set_current_state_id/1,
16		current_options/1, set_current_options/1,
17		get_current_predecessor_state_id/1,
18
19		add_id_at_front/1, add_id_at_end/1,
20		add_id_random/1, /* from state_space_open_nodes_c */
21		add_id_with_weight/2, add_id_to_process/3,
22		pop_id_from_front/1, pop_id_from_end/1, pop_id_oldest/1,
23		retract_open_node/1, open_ids_empty/0,
24		top_front_id/1, top_front_weight/1,
25
26		visited_expression/3, visited_expression/2, visited_expression_id/1,
27		find_hashed_packed_visited_expression/3,
28		retract_visited_expression/2,
29		not_all_transitions_added/1,
30		not_invariant_checked/1, set_invariant_checked/1,
31		invariant_not_yet_checked/1, invariant_still_to_be_checked/1,
32		not_interesting/1, % nodes ignored because they do not satisfy a user-provided scope predicate
33		mark_as_not_interesting/1,
34		max_reached_for_node/1,
35		max_reached_or_timeout_for_node/1,
36		use_no_timeout/1, time_out_for_node/1, time_out_for_node/3,
37		hash_to_id/2,id_to_marker/2, hash_to_nauty_id/2,
38		register_back_edge/2, try_compute_depth_of_state_id/2,
39		invariant_violated/1, time_out_for_invariant/1, time_out_for_assertions/1,
40		set_invariant_violated/1,
41
42		state_error_exists/0, state_error/3, store_state_error/3,
43		set_context_state/1, set_context_state/2,
44		update_context_state/1, clear_context_state/0, get_current_context_state/1,
45		store_error_for_context_state/2,
46		copy_current_errors_to_state/2,
47		store_abort_error_for_context_state_if_possible/4,
48		abort_error_exists_in_context_state/1,
49
50		transition/3,transition/4, any_transition/3,
51		store_transition/4,
52		deadlocked_state/1, % no outgoing edge
53		is_initial_state_id/1, is_concrete_constants_state_id/1,
54		multiple_concrete_constants_exist/0,
55		get_constants_state_for_id/2, get_constants_state_for_id/3,
56		get_constants_state_id_for_id/2,
57		try_get_unique_constants_state/1,
58		get_constants_id_for_state_id/2,
59		get_variables_state_for_id/2,
60		out_degree/2,
61		operation_not_yet_covered/1, operation_name_not_yet_covered/1,
62		get_operation_name_coverage_infos/4,
63		mark_operation_as_covered/1,
64		initialise_operation_not_yet_covered/0,
65
66		transition_info/2, store_transition_infos/2,
67		keep_transition_info/1,
68		compute_transitions_if_necessary/1,
69
70		state_space_initialise/0, state_space_initialise_with_stats/0,
71		state_space_reset/0,
72		state_space_add/2, state_space_packed_add/2,
73		delete_node/1,
74
75		current_state_corresponds_to_initialised_b_machine/0,
76		current_state_corresponds_to_fully_setup_b_machine/0,
77		current_state_corresponds_to_setup_constants_b_machine/0,
78		visited_state_corresponds_to_initialised_b_machine/1,
79		visited_state_corresponds_to_setup_constants_b_machine/1,
80
81		specialized_inv/2, %reuse_operation/4,
82		assert_max_reached_for_node/1, assert_time_out_for_node/3,
83		assert_time_out_for_invariant/1, assert_time_out_for_assertions/1,
84
85		set_max_nr_of_new_impl_trans_nodes/1,
86		get_max_nr_of_new_impl_trans_nodes/1,
87		impl_trans_term/3, impl_trans_term_all/2,
88		impl_trans_id/4, impl_trans_not_complete/1,
89		compute_transitions_if_necessary_saved/1,
90		max_nr_of_new_nodes_limit_not_reached/0,
91
92		find_trace_to_initial_state/2, find_initialised_states/1,
93
94		tcltk_save_state_space/1, tcltk_load_state/1,
95		compute_full_state_space_hash/1,
96
97		execute_id_trace_from_current/3,
98		set_trace_by_transition_ids/1, try_set_trace_by_transition_ids/1,
99		extend_trace_by_transition_ids/1,
100		extract_term_trace_from_transition_ids/2,
101
102		add_counterexample_node/1, add_counterexample_op/1,
103		reset_counterexample/0, set_counterexample_by_transition_ids/1,
104		counterexample_node/1, counterexample_op/1 % specific predicates to register counter examples
105		]).
106
107		:- use_module(library(lists)).
108
109		:- use_module(self_check).
110		:- use_module(error_manager).
111		:- use_module(gensym).
112		:- use_module(preferences).
113		:- use_module(tools).
114		%:- use_module(state_space_exploration_modes,[compute_hash/3]).
115
116		:- use_module(extension('counter/counter'),
117		[counter_init/0, new_counter/1, get_counter/2, inc_counter/1, inc_counter/2, inc_counter_by/2, reset_counter/1, set_counter/2]).
118
119		:- use_module(module_information).
120		:- module_info(group,state_space).
121		:- module_info(description,'This module keeps track of the visited states by the animator/model checker.').
122
123		% ----------------------------------
124
125		:- load_files(library(system), [when(compile_time), imports([environ/2])]).
126		:- if((environ(prob_myheap,false) ; \+ predicate_property(load_foreign_resource(_), _))).
127		:- use_module(state_space_open_nodes). %% comment in to use only Prolog datastructures
128		:- else.
129		:- use_module(state_space_open_nodes_c). %% comment in to use C++ multimap queue; can make use of HEURISTIC_FUNCTION
130		:- endif.
131
132		% ----------------------------------
133
134		get_state_space_stats(NrNodes,NrTransitions,ProcessedNodes) :-
135		get_counter(states,N), NrNodes is N+1,
136		get_counter(transitions,NrTransitions),
137		get_counter(processed_nodes,ProcessedNodes).
138
139		get_state_space_stats(NrNodes,NrTransitions,ProcessedNodes,IgnoredNodes) :-
140		get_state_space_stats(NrNodes,NrTransitions,ProcessedNodes),
141		get_counter(not_interesting_nodes,IgnoredNodes).
142
143		gen_new_state_id(Nr) :-
144		inc_counter(states,N1), Nr is N1-1. % only one C call
145		%get_counter(states,Nr), inc_counter(states).
146		reset_state_counter :- reset_counter(states).
147		reset_state_counter(Nr) :- set_counter(states,Nr).
148
149		get_state_id_trace(StateIds) :-
150		history(History),
151		current_state_id(CurID),
152		reverse([CurID|History],StateIds).
153
154		get_current_predecessor_state_id(PriorID) :-
155		history([PriorID|_]).
156
157		:- dynamic history/1.
158		history([]).
159
160
161		:- dynamic forward_history/1.
162
163		:- dynamic current_state_id/1.
164		current_state_id(root).
165		/* INITIAL STATE, third arg: clp(fd) constraints as generated
166		by fd_copy_term */
167
168		current_expression(ID,State) :- current_state_id(ID),
169		visited_expression(ID,State).
170		current_packed_expression(ID,State) :- current_state_id(ID),
171		packed_visited_expression(ID,State).
172
173		:- use_module(specfile,[state_corresponds_to_initialised_b_machine/1,
174		state_corresponds_to_fully_setup_b_machine/1,
175		state_corresponds_to_set_up_constants/1]).
176		current_state_corresponds_to_initialised_b_machine :-
177		current_packed_expression(_,PS), unpack_state_top_level(PS,TLState),
178		state_corresponds_to_initialised_b_machine(TLState).
179		visited_state_corresponds_to_initialised_b_machine(ID) :-
180		packed_visited_expression(ID,PS), unpack_state_top_level(PS,TLState),
181		state_corresponds_to_initialised_b_machine(TLState).
182
183		current_state_corresponds_to_fully_setup_b_machine :-
184		current_packed_expression(_,PS), unpack_state_top_level(PS,TLState),
185		state_corresponds_to_fully_setup_b_machine(TLState).
186
187		current_state_corresponds_to_setup_constants_b_machine :-
188		current_packed_expression(_,PS), unpack_state_top_level(PS,TLState),
189		state_corresponds_to_set_up_constants(TLState).
190
191		visited_state_corresponds_to_setup_constants_b_machine(ID) :-
192		packed_visited_expression(ID,PS), unpack_state_top_level(PS,TLState),
193		state_corresponds_to_set_up_constants(TLState).
194
195		:- dynamic current_options/1.
196		current_options([]).
197
198		set_current_options(Options) :-
199		retractall( current_options(_) ),
200		assertz( current_options(Options) ).
201
202		:- dynamic packed_visited_expression/2.
203		%packed_visited_expression(v_0,true).
204
205		:- use_module(state_packing).
206
207		retract_visited_expression(ID,State) :- retract(packed_visited_expression(ID,PState)),
208		unpack_state(PState,State).
209
210		retractall_visited_expression(ID) :- retractall(packed_visited_expression(ID,_)).
211
212		state_space_packed_add(Id,PackedTerm) :- assertz(packed_visited_expression(Id,PackedTerm)).
213
214		state_space_add(Id,Term) :-
215		(pack_state(Term,PackedTerm) -> assertz(packed_visited_expression(Id,PackedTerm))
216		; add_internal_error('State packing failed: ',pack_state(Term,_)),
217		assertz(packed_visited_expression(Id,Term))).
218
219		% deprecated:
220		visited_expression(ID,State,true) :- visited_expression(ID,State).
221		% not call(CurBody); for the moment we always have true as last argument
222
223	?	visited_expression(A,B) :- packed_visited_expression(A,PB),
224		(unpack_state(PB,R) -> B=R ; add_internal_error('Unpacking state failed: ',unpack_state(PB,R)),R=A).
225
226		%visited_expression_id(A) :- packed_visited_expression(A,_). % avoid unpacking state
227		% even better: not to look up fact at all to avoid constructing state term, this is done below:
228		:- use_module(library(between),[between/3]).
229		visited_expression_id(ID) :- number(ID),!, ID>=0, get_counter(states,N), ID<N.
230		visited_expression_id(ID) :- ID==root,!.
231		visited_expression_id(root).
232	?	visited_expression_id(Nr) :- Nr \== root, get_counter(states,N), N1 is N-1, between(0,N1,Nr).
233
234		% given a hash and a packed state: find ID (fail if does not exist)
235		find_hashed_packed_visited_expression(Hash,PackedState,ID) :-
236		hash_to_id(Hash,ID),
237		(packed_visited_expression(ID,PackedState)
238		-> true /* warning: may instantiate State if not ground */
239		; print(hash_collision(Hash,ID)),nl,fail
240		).
241
242
243		:- dynamic not_invariant_checked/1.
244		set_invariant_checked(ID) :- %print(inv_checked(ID)),nl,
245	?	retract(not_invariant_checked(ID)).
246
247		invariant_not_yet_checked(ID) :-
248		not_all_transitions_added(ID) ; /* assumption: if not all transitions added then we haven't checked invariant yet */
249		not_invariant_checked(ID) ;
250		not_interesting(ID). % assumption: if a node is marked as not interesting it will not be examined
251
252		% difference with invariant_not_yet_checked: not interesting nodes not reported and cannot be backtracked
253		invariant_still_to_be_checked(ID) :-
254		(not_all_transitions_added(ID) -> true ; not_invariant_checked(ID) -> true).
255
256		:- dynamic not_interesting/1.
257		%not_interesting(v_0).
258
259		:- dynamic max_reached_for_node/1.
260		/* true if not all outgoing transistions were computed due to the limit
261		on the number of operations/initialisations computed */
262		:- dynamic time_out_for_node/3, use_no_timeout/1, time_out_for_invariant/1, time_out_for_assertions/1.
263
264		time_out_for_node(ID) :- (var(ID) -> visited_expression_id(ID) ; true),
265		(time_out_for_node(ID,_,_) -> true ; fail).
266
267		:- dynamic transition/4.
268		%transition(v_0,a,1,v_1).
269
270		store_transition(Org,Action,Dest,Id) :-
271		%get_counter(transitions,Id), inc_counter(transitions),
272		inc_counter(transitions,Id1), Id is Id1-1, % only one C call
273		assertz(transition(Org,Action,Id,Dest)).
274
275	?	deadlocked_state(Origin) :- \+ any_transition(Origin,_,_).
276
277		is_concrete_constants_state_id(ID) :-
278	?	transition(root,_,ID),
279		packed_visited_expression(ID,concrete_constants(_)).
280
281		% check if we have multiple constant setups
282		multiple_concrete_constants_exist :-
283	?	is_concrete_constants_state_id(ID),
284	?	is_concrete_constants_state_id(ID2), ID2 \= ID,!.
285
286
287		is_initial_state_id(InitialStateID) :-
288		transition(root,_,State),
289		packed_visited_expression(State,P),
290		(P = concrete_constants(_) % also covers '$partial_setup_constants'
291		-> state_space:transition(State,_,InitialStateID)
292		; InitialStateID=State).
293
294		% get the constants for a state (if there are constants), avoid unpacking variables
295		get_constants_state_for_id(ID,CS) :- get_constants_state_for_id(ID,[],CS).
296		get_constants_state_for_id(ID,Opts,ConstantsState) :-
297		packed_visited_expression(ID,PState),
298		unpack_state_top_level(PState,TLState),
299		(TLState = const_and_vars(CID,_) -> get_constants_state_for_id(CID,[],ConstantsState)
300		; unpack_state(PState,UPState),
301		(UPState = concrete_constants(CS) -> ConstantsState=CS
302		; UPState = [_|_], member(allow_variable_list,Opts),
303		ConstantsState=UPState,
304		% could be that we have a state where constants and variables are mixed in a single list
305		% e.g., ProB2's FindStateCommand does currently not create new intermediate constant states
306		add_message(get_constants_state_for_id,'State is a list of bindings and has no reference to a constant valuation: ',ID)
307		)
308		).
309
310		% get the state id for associated constants state for a state (if there are constants)
311		get_constants_state_id_for_id(ID,CstID) :-
312		packed_visited_expression(ID,PState),
313		unpack_state_top_level(PState,TLState),
314		get_constants_id_for_id_aux(TLState,ID,CstID).
315		get_constants_id_for_id_aux(concrete_constants(_),ID,ID).
316		get_constants_id_for_id_aux(const_and_vars(ID,_),_,ID).
317
318		get_variables_state_for_id(ID,VarState) :-
319		visited_expression(ID,State),
320		get_vars_aux(State,VarState).
321		%get_vars_aux(concrete_constants(ConstantsState),[]).
322		get_vars_aux(const_and_vars(_,Vars),State) :- !, State=Vars.
323		get_vars_aux([],[]).
324		get_vars_aux([H|T],[H|T]).
325
326		% check if there is a unique constants state:
327		try_get_unique_constants_state(ConstantsState) :-
328		transition(root,_,_TransID,DestID),
329		\+ (transition(root,_,_,DestID2), DestID2 \= DestID), % no other transition exists
330		\+ max_reached_or_timeout_for_node(root),
331		DestID \= root, % DestID=root should never happen
332		get_constants_state_for_id(DestID,ConstantsState).
333
334		% returns id of constants state for a state (if it exists)
335		get_constants_id_for_state_id(ID,ConstID) :-
336		packed_visited_expression(ID,'$cst_vars'(ConstID,_)).
337
338	?	any_transition(Origin,TransID,Destination) :- transition(Origin,_,TransID,Destination).
339
340	?	transition(Origin,Action,Destination) :- transition(Origin,Action,_TransID,Destination).
341
342		:- dynamic transition_info/2.
343		store_transition_infos([],_TransId).
344		store_transition_infos([Info|Irest],TransId) :-
345		store_transition_info(Info,TransId),
346		store_transition_infos(Irest,TransId).
347		store_transition_info(Info,TransId) :- %print(info(Info,TransId)),nl,
348		(keep_transition_info(Info)
349		-> assertz(transition_info(TransId,Info))
350		; true).
351
352		% Do not store path info by default
353		keep_transition_info(path(_)) :- !,fail.
354		keep_transition_info(eventtrace(_)) :- !,preference(eventtrace,true).
355		keep_transition_info(event(_)) :- !,preference(store_event_transinfo,true).
356		keep_transition_info(_). % store everything else
357
358		reset_transition_store :-
359		retractall(transition(_,_,_,_)),
360		retractall(transition_info(_,_)),
361		reset_counter(transitions),
362		reset_counterexample.
363
364		/*
365		Version with packing of transitions:
366		store_transition(Org,Action,Dest,Id) :-
367		retract(transition_counter(Id)),
368		NewId is Id+1,
369		assertz(transition_counter(NewId)),
370		Action =.. [ActionName|Parameters],
371		pack_values(Parameters,PackedParameters),
372		assertz(packed_transition(Org,ActionName,PackedParameters,Id,Dest)).
373
374		transition(Origin,Action,TransID,Destination) :- nonvar(Action),!,
375		Action =.. [ActionName|Parameters],
376		packed_transition(Origin,ActionName,PackedParameters,TransID,Destination),
377		unpack_values(PackedParameters,Parameters).
378		transition(Origin,Action,TransID,Destination) :-
379		packed_transition(Origin,ActionName,PackedParameters,TransID,Destination),
380		unpack_values(PackedParameters,Parameters),
381		Action =.. [ActionName|Parameters].
382		any_transition(Origin,TransID,Destination) :- packed_transition(Origin,_,_,TransID,Destination).
383		*/
384
385		% compute out-degree of a node
386		out_degree(ID,OutDegree) :- findall(0, transition(ID,_,_,_), L), length(L,OutDegree).
387
388	?	operation_name_not_yet_covered(OpName) :- operation_not_yet_covered(OpName).
389
390
391		get_operation_name_coverage_infos(PossibleNr,FeasibleNr,UncovNr,UncoveredList) :-
392		findall(ON, specfile:get_possible_event(ON), Possible), length(Possible,PossibleNr),
393		findall(OF, specfile:get_feasible_event(OF), Feasible), length(Feasible,FeasibleNr),
394		findall(OpName, state_space: operation_name_not_yet_covered(OpName), UncoveredList),
395		length(UncoveredList,UncovNr).
396
397
398		:- dynamic operation_not_yet_covered/1.
399		%operation_not_yet_covered(b).
400
401		:- use_module(probsrc(debug),[formatsilent/2]).
402		mark_operation_as_covered(OpName) :-
403		(retract(operation_not_yet_covered(OpName))
404		-> (preferences:get_preference(provide_trace_information,true)
405		-> formatsilent('Covered ~w~n',[OpName])
406		; true),
407	?	(operation_not_yet_covered(_) -> true ; formatsilent('~nALL OPERATIONS COVERED~n',[]))
408		; true
409		).
410
411
412		:- use_module(bmachine,[b_top_level_operation/1]).
413		:- use_module(debug,[debug_println/1]).
414		:- use_module(probcspsrc(haskell_csp),[channel/2]).
415		initialise_operation_not_yet_covered :- retractall(operation_not_yet_covered(_)),
416		b_or_z_mode,
417	?	b_top_level_operation(Name),
418		% b_get_machine_operation(Name,_,Par,_), length(Par,Arity), functor(Op,Name,Arity),
419		% Note: no '-->' added
420		assertz(operation_not_yet_covered(Name)),
421		debug_println(operation_not_yet_covered(Name)),
422		fail.
423		/* Missing: treat operations with return values */
424		initialise_operation_not_yet_covered :- csp_mode, \+ csp_with_bz_mode,
425	?	channel(Name,_),
426		assertz(operation_not_yet_covered(Name)),
427		debug_println(operation_not_yet_covered(Name)),
428		fail.
429		initialise_operation_not_yet_covered.
430
431		state_error_exists :- state_error(_,_,_),!.
432		:- dynamic state_error/3.
433
434		%state_error([],invariant_violated).
435
436		reset_next_state_error_id_counter :- reset_counter(next_state_error_id).
437		:- use_module(tools_printing, [print_error/1, format_error_with_nl/2]).
438		:- use_module(error_manager,[print_error_span/1]).
439		store_state_error(State,Error,Id) :- state_error(State,Id,Error),!. % do not store identical error twice
440		store_state_error(State,Error,Id) :-
441		%retract( next_state_error_id(Id) ),
442		inc_counter(next_state_error_id,Id),
443		% tools_printing:print_term_summary(Error),nl, tools_printing:nested_print_term(Error),nl,
444		assertz( state_error(State,Id,Error) ).
445		store_error_for_context_state(Error,Id) :-
446		( context_state(State,Errs) ->
447		(Errs<25
448		-> store_state_error(State,Error,Id), E1 is Errs+1,
449		%assertz(context_state(State,E1))
450		set_context_number_of_errors(E1)
451		; store_state_error(State,max_state_errors_reached(25),Id)
452		)
453		;
454		add_internal_error('No known context when calling store_error_for_context_state: ',store_error_for_context_state(Error,Id)),
455		fail).
456
457		% check if we already have a certain type of error in the current context state
458		abort_error_exists_in_context_state(ErrType) :- get_current_context_state(State),
459		Error = abort_error(ErrType,_Msg,_Term,_Pos),
460		state_error(State,_Id,Error).
461
462		% copy current errors from error_manager to state errors
463		copy_current_errors_to_state(StateID,Context) :-
464		% error_manager:logged_error(Source,ErrMsg,_Context,Span), % will not retract
465		error_manager:get_error_with_span(Source,ErrMsg,Span), % will retract
466		store_state_error(StateID,abort_error(Source,ErrMsg,'',span_context(Span,Context)),SID),
467		% TO DO: use other error class
468		debug_println(stored(Source,SID,_Context,ErrMsg)),
469		fail.
470		copy_current_errors_to_state(_,_).
471
472		store_abort_error_for_context_state_if_possible(ErrType,Msg,Term,Span) :-
473		%print(store(Msg,Term,Span)),nl,
474		( get_current_context_state(State) ->
475		error_manager:get_error_context(Context),
476		(abort_error_for_same_location_exists(State,Id1,ErrType,Msg,Span),
477		abort_error_for_same_location_exists(State,Id2,ErrType,Msg,Span),
478		Id2>Id1
479		-> /* two errors of same type, for same state and same source location exists */
480		/* TO DO: maybe merge state errors */
481		simplify_span(Span,Span1),
482		compress_span(Span1,Span2),
483		store_state_error(State,abort_error(ErrType,'Further identical errors occurred (not stored !)',Term,span_context(Span2,Context)),_)
484		;
485		format_error_with_nl('! An error occurred in state ~w: ~w !',[State,ErrType]),
486		% usual errors: precondition_error, while_invariant_violation, while_variant_error,
487		% assert_error, well_definedness_error, card_overflow_error
488		print_error(Msg),
489		print_error_term(Term,Span),
490		% print_error(context_state_id(State)), % printed by print_error_context
491		print_error_context,
492		(debug_mode(on),visited_expression(State,S) -> translate:translate_bstate(S,O),print_error(O) ; true),
493		compress_span(Span,Span2),
494		print_error_span(Span2),
495		store_state_error(State,abort_error(ErrType,Msg,Term,span_context(Span2,Context)),_)
496		),
497		(add_new_event_in_error_scope(abort_error(ErrType)) -> true ; true), % should we use well_definedness_error?
498		assert_real_error_occurred(abort_error) % Note that in this case the error manager list of errors maybe empty even though real_error_occured is true. (see ProB2 kernel test de.prob.cli.integration.rules.RulesMachineTest > testReuseStateSpace)
499		; % no current context_state exists:
500		compress_span(Span,Span2),
501		add_error(ErrType,Msg,Term,Span2)
502		).
503
504
505		:- use_module(bsyntaxtree, [find_identifier_uses/3]).
506		compress_span(span_context(Span,C),span_context(CS,C)) :- !,
507		compress_span(Span,CS).
508		compress_span(pos_context(Span1,C,Span2),pos_context(CS1,C,CS2)) :- !,
509		compress_span(Span1,CS1),
510		compress_span(Span2,CS2).
511		compress_span(span_predicate(Pred,LS,S),Res) :- find_identifier_uses(Pred,[],Ids),
512		sort(Ids,SIds),
513		filter_state(LS,SIds,FLS),
514		filter_state(S,SIds,FS), % TODO: do we need to store the global state? we can reconstruct it ?
515		% format('Compressed span_predicate (~w)~n',[Ids]),
516		!,
517		Res = span_predicate(Pred,FLS,FS).
518		compress_span(S,S).
519		% avoid storing large useless values
520		% TO DO: probably we should stop storing spans when a certain threshold of number of errors is reached
521
522
523		:- use_module(library(ordsets),[ord_member/2]).
524		filter_state([],_,[]).
525		filter_state([bind(ID,L)|T],Vars,Res) :-
526		(ord_member(ID,Vars) -> Res = [bind(ID,L)|RT] ; Res=RT),
527		filter_state(T,Vars,RT).
528
529
530		:- use_module(translate, [translate_error_term/3]).
531		print_error_term(T,S) :- (var(T);var(S)),!,
532		print_error('### VARIABLE error term or span:'), print_error(print_error_term(T,S)).
533		print_error_term(Term,Span) :- translate_error_term(Term,Span,S),
534		(S='' -> true ; print_error(S)).
535
536		abort_error_for_same_location_exists(State,Id,ErrType,Msg,Span) :-
537	?	state_error(State,Id,abort_error(ErrType,Msg,_Term2,span_context(Span2,_Ctxt2))),
538		same_span_location(Span2,Span).
539		% should be moved to error_manager ?
540		same_span_location(span_context(Span1,C),span_context(Span2,C)) :- !, same_span_location(Span1,Span2).
541		same_span_location(pos_context(Span1,C,_),pos_context(Span2,C,_)) :- !,
542		same_span_location(Span1,Span2). % should we check second span?
543		same_span_location(span_predicate(Pred1,_,_),span_predicate(Pred2,_,_)) :- !,Pred1=Pred2.
544		same_span_location(X,X).
545
546		:- dynamic saved_nested_context_state/2.
547		save_nested_context_state(_S) :-
548		bb_get(state_space_context_state,ID),
549		bb_get(state_space_context_errors,Errs),!,
550		%print(saving_context_state(_S,ID,Errs)),nl,
551		asserta(saved_nested_context_state(ID,Errs)).
552		save_nested_context_state(_).
553
554		% actually pops context state
555		clear_context_state :-
556	?	retract(saved_nested_context_state(ID,Errs)),!, %print(restoring_nested(ID,Errs)),nl,
557		bb_put(state_space_context_state,ID),
558		bb_put(state_space_context_errors,Errs).
559		clear_context_state :-
560		(bb_delete(state_space_context_state,_) -> true ; true).
561		%(retract(context_state(_,_)) -> true ; true). % retractall seems to be slowing down with use
562
563		% Note: Each Prolog module maintains its own blackboard for bb_get/bb_put
564		context_state(ID,Errs) :-
565		bb_get(state_space_context_state,ID), bb_get(state_space_context_errors,Errs).
566
567		% sets a new context state; pushing the previous one if necessary
568		set_context_state(State) :- %print(set_id(State)),nl,
569		save_nested_context_state(State),
570		bb_put(state_space_context_state,State),
571		bb_put(state_space_context_errors,0).
572
573		set_context_state(State,_Context) :- % Context can be used for debugging later
574		set_context_state(State).
575
576		% update current context state, without storing nested states
577		update_context_state(State) :-
578		bb_put(state_space_context_state,State),
579		bb_put(state_space_context_errors,0).
580
581		get_current_context_state(ID) :- bb_get(state_space_context_state,ID).
582		%get_current_context_state(ID) :- context_state(ID,_).
583
584		set_context_number_of_errors(Errs) :- bb_put(state_space_context_errors,Errs).
585
586		retractall_invariant_violated(State) :-
587		retractall(state_error(State,_,invariant_violated)).
588		invariant_violated(State) :-
589	?	state_error(State,_,invariant_violated).
590		set_invariant_violated(State) :-
591		( invariant_violated(State) -> true
592		; time_out_for_invariant(ID) -> print('Timeout for node: '), print(ID),nl,
593		print('Not setting invariant violation status'),nl
594		; store_state_error(State,invariant_violated,_)
595		).
596
597		%:- set_invariant_violated([]). % why is this ??
598
599
600		:- dynamic hash_to_id/2.
601		:- dynamic id_to_marker/2.
602		:- dynamic id_back_edge/3. % optional facts to keep track where a state was constructed from
603
604		:- dynamic hash_to_nauty_id/2. % used in nauty mode to map nauty id's to hash values
605
606		:- dynamic specialized_inv/2. /* stores whether for a node a specialized invariant
607		version could be computed */
608
609		% :- dynamic reuse_operation/4. /* when for a state and given operation name we can reuse the operation computed for another state */
610		% used to be used for OPERATION_REUSE TRUE
611
612		:- use_module(hashing).
613		state_space_startup :- % call once at startup to ensure all counters exist
614		counter_init,
615		new_counter(states), new_counter(processed_nodes), new_counter(transitions),
616		new_counter(next_state_error_id),
617		new_counter(not_interesting_nodes),
618		reset_open_ids. % also calls myheap init
619		state_space_initialise :- counter_init, reset_gennum, reset_gensym,
620		new_counter(states), new_counter(processed_nodes), new_counter(transitions),
621		new_counter(next_state_error_id), new_counter(not_interesting_nodes),
622		reset_state_counter, reset_processed_nodes_counter, reset_next_state_error_id_counter,
623		retractall_visited_expression(_),
624		reset_open_ids,
625		reset_stored_values, % state_packing
626		retractall(not_invariant_checked(_)),
627		reset_not_interesting,
628		retractall(max_reached_for_node(_)),
629		retractall(time_out_for_node(_,_,_)),
630		retractall(time_out_for_invariant(_)),
631		retractall(time_out_for_assertions(_)),
632		retractall(use_no_timeout(_)),
633		retractall(state_error(_,_,_)),
634		clear_context_state,
635		reset_transition_store,
636		retractall(operation_not_yet_covered(_)),
637		retractall(hash_to_id(_,_)),
638		retractall(id_back_edge(_,_,_)),
639		retractall(hash_to_nauty_id(_,_)),
640		retractall(id_to_marker(_,_)),
641		retractall(specialized_inv(_,_)),
642		%retractall(reuse_operation(_,_,_,_)),
643		state_space_add(root,root),
644		add_id_at_front(root),
645		my_term_hash(root,RootHash),
646		assertz(hash_to_id(RootHash,root)),
647		%assertz(not_invariant_checked(root)),
648		state_space_reset.
649
650		:- use_module(eventhandling,[register_event_listener/3]).
651		:- register_event_listener(startup_prob,state_space_startup,
652		'Initialise Statespace Counters.').
653		:- register_event_listener(reset_specification,state_space_initialise,
654		'Reset Statespace.').
655		:- register_event_listener(change_of_animation_mode,state_space_initialise,
656		'Reset Statespace.').
657		:- register_event_listener(specification_initialised,initialise_operation_not_yet_covered,
658		'Init coverage info.').
659		:- register_event_listener(reset_prob,state_space_initialise,
660		'Reset Statespace.').
661
662		/* A version of reset which checks how much memory is used by each fact */
663		/* state_space:init_with_stats */
664		state_space_initialise_with_stats :-
665		reset_gennum, reset_gensym, reset_state_counter, reset_processed_nodes_counter,
666		reset_next_state_error_id_counter,
667	?	retract_open_ids_with_statistics,
668	?	retract_with_statistics(state_space,[packed_visited_expression(_,_),
669		not_invariant_checked(_),
670		not_interesting(_),
671		max_reached_for_node(_),
672		time_out_for_node(_,_,_),
673		time_out_for_invariant(_),
674		time_out_for_assertions(_),
675		use_no_timeout(_),
676		state_error(_,_,_),
677		transition(_,_,_,_),
678		transition_info(_,_),
679		operation_not_yet_covered(_),
680		hash_to_id(_,_),
681		hash_to_nauty_id(_,_),
682		id_to_marker(_,_),
683		specialized_inv(_,_),
684		%reuse_operation(_,_,_,_),
685		history(_), forward_history(_), op_trace_ids(_)]),
686		reset_not_interesting,
687	?	retract_stored_values_with_statistics,
688		clear_context_state,
689		reset_transition_store,
690		state_space_add(root,root),
691		add_id_at_front(root),
692		%assertz(not_invariant_checked(root)),
693		state_space_reset,
694		initialise_operation_not_yet_covered.
695
696
697
698		:- dynamic op_trace_ids/1.
699		reset_trace :- retractall(op_trace_ids(_)), assertz(op_trace_ids([])).
700		get_action_trace(T) :- trace(T).
701		get_action_term_trace(PT) :- get_action_trace_with_limit(0,T), project_on_action_term(T,PT).
702		trace(Trace) :- get_action_trace_with_limit(500,Trace).
703		get_action_trace_with_limit(Limit,Trace) :-
704		op_trace_ids(IDT), reverse(IDT,RIDT),
705		extract_trace_from_transition_ids(RIDT,root,Limit,[],Trace).
706
707		reset_op_trace_ids :- retractall(op_trace_ids(_)), assertz(op_trace_ids([])).
708		add_to_op_trace_ids(OpID) :- retract(op_trace_ids(OpIDS)), assertz(op_trace_ids([OpID|OpIDS])).
709		remove_from_op_trace_ids(OpID) :- retract(op_trace_ids(OpIDS)),
710		(OpIDS = [R|Rest]
711		-> assertz(op_trace_ids(Rest)), OpID = R
712		; assertz(op_trace_ids(OpIDS)), fail).
713
714		% translate a list of transition ids (from root) into a list of operation terms
715		extract_term_trace_from_transition_ids(TransIDListFromRoot,Trace) :-
716		extract_trace_from_transition_ids(TransIDListFromRoot,root,0,[],ActionTrace),
717		reverse_and_project_on_action_term(ActionTrace,[],Trace).
718
719		reverse_and_project_on_action_term([],A,A).
720		reverse_and_project_on_action_term([action(_,Term)|T],Acc,Res) :- !,
721		reverse_and_project_on_action_term(T,[Term|Acc],Res).
722		reverse_and_project_on_action_term([H|T],Acc,Res) :-
723		add_error(reverse_and_project_on_action_term,'Illegal action: ',H),
724		reverse_and_project_on_action_term(T,[H|Acc],Res).
725
726		project_on_action_term([],[]).
727		project_on_action_term([action(_,Term)|T],Res) :- !, Res=[Term|TR],
728		project_on_action_term(T,TR).
729		project_on_action_term([H|T],Res) :-
730		add_error(project_on_action_term,'Illegal action: ',H),
731		project_on_action_term(T,Res).
732
733		extract_trace_from_transition_ids([],_CurrentState,_,Trace,Trace).
734		extract_trace_from_transition_ids([TransId|Rest],CurrentState,Limit,AccTrace,Trace) :-
735		compute_op_string(TransId,CurrentState,Limit,OpTerm,OpString,DestState),!,
736		extract_trace_from_transition_ids(Rest,DestState,Limit,
737		[action(OpString,OpTerm)|AccTrace],Trace).
738		extract_trace_from_transition_ids([TransId|_],CurrentState,_,_,_Trace) :-
739		add_error(state_space,'Could not execute transition id: ', TransId:from(CurrentState)),fail.
740
741		:- use_module(translate,[translate_event_with_src_and_target_id/5]).
742		compute_op_string(jump(TO),_CurID,_,Term,String,DestID) :- !, Term=jump,String=jump,DestID=TO.
743		compute_op_string(TransId,CurID,Limit,Term,String,DestID) :- transition(CurID,Term,TransId,DestID),
744		translate_event_with_src_and_target_id(Term,CurID,DestID,Limit,String).
745
746		% reset history and forward history, but not state-space itself
747		state_space_reset :-
748		reset_trace,
749		retractall(history(_)),
750		retractall(forward_history(_)),
751		retractall(current_state_id(_)),
752		retractall(current_options(_)),
753		assertz(history([])),
754		assertz(current_state_id(root)).
755
756		reset_not_interesting :- retractall(not_interesting(_)), reset_counter(not_interesting_nodes).
757
758		mark_as_not_interesting(ID) :- assertz(not_interesting(ID)), inc_counter(not_interesting_nodes).
759
760		set_current_state_id(ID) :- (retract(current_state_id(_)) -> true ; true),
761		assertz(current_state_id(ID)).
762
763		state_space_clean_all :-
764		retractall(state_space_version_in_file(_)),
765		retractall_visited_expression(_),
766		reset_open_ids,
767		retractall(not_invariant_checked(_)),
768		reset_not_interesting,
769		retractall(max_reached_for_node(_)),
770		retractall(time_out_for_node(_,_,_)),
771		retractall(time_out_for_invariant(_)),
772		retractall(time_out_for_assertions(_)),
773		retractall(use_no_timeout(_)),
774		retractall(state_error(_,_,_)),
775		clear_context_state,
776		reset_transition_store,
777		retractall(operation_not_yet_covered(_)),
778		retractall(hash_to_id(_,_)),
779		retractall(id_back_edge(_,_,_)),
780		retractall(hash_to_nauty_id(_,_)),
781		retractall(id_to_marker(_,_)),
782		retractall(specialized_inv(_,_)),
783		%retractall(reuse_operation(_,_,_,_)),
784		retractall(history(_)),
785		retractall(forward_history(_)),
786		retractall(op_trace_ids(_)),
787		retractall(current_state_id(_)),
788		retractall(current_options(_)).
789
790		% this is only used from within the Tcl/Tk animator at the moment:
791		delete_node(ID) :- print(deleting(ID)),nl,
792		retractall_visited_expression(ID),
793		retractall_invariant_violated(ID),
794		retract_open_node_and_update_processed_nodes(ID),
795		retractall(not_invariant_checked(ID)),
796		(retract(not_interesting(ID)) -> inc_counter_by(not_interesting_nodes,-1) ; true),
797		retractall(max_reached_for_node(ID)),
798		retractall(time_out_for_node(ID,_,_)),
799		retractall(time_out_for_invariant(ID)),
800		retractall(time_out_for_assertions(ID)),
801		retractall(use_no_timeout(ID)),
802		retractall(state_error(ID,_,_)),
803		retractall(transition(ID,_,_,_)),
804		% to do: check if operation_not_yet_covered(_) changes
805		retract_hash(ID),
806		retractall(id_to_marker(ID,_)).
807
808		retract_hash(ID) :- retract(hash_to_id(Hash,ID)), retractall(hash_to_nauty_id(_TermHash,Hash)),fail.
809		retract_hash(_).
810
811		assert_max_reached_for_node(Id) :- %print_message(max_reached_for_node(Id)),
812		(max_reached_for_node(Id) -> true ; assertz(max_reached_for_node(Id))).
813
814		:- use_module(probsrc(debug),[debug_mode/1]).
815		assert_time_out_for_node(Id,OpName,TypeOfTimeOut) :-
816		(debug_mode(off),functor(TypeOfTimeOut,virtual_time_out,_) -> true % can easily happen when parameters are unbounded
817		; print_message(time_out_for_node(Id,OpName,TypeOfTimeOut))),
818		(time_out_for_node(Id,OpName,_) -> true ; assertz(time_out_for_node(Id,OpName,TypeOfTimeOut))).
819		assert_time_out_for_invariant(Id) :- print_message(time_out_for_invariant(Id)),
820		(time_out_for_invariant(Id) -> true ; assertz(time_out_for_invariant(Id))).
821		assert_time_out_for_assertions(Id) :- print_message(time_out_for_assertions(Id)),
822		(time_out_for_assertions(Id) -> true ; assertz(time_out_for_assertions(Id))).
823
824		max_reached_or_timeout_for_node(Id) :-
825	?	(max_reached_for_node(Id) ; time_out_for_node(Id,_,_)).
826		/* ---------------------- */
827		/* state space saving */
828		/* ---------------------- */
829
830		:- dynamic state_space_version_in_file/1. %
831		state_space_version(1).
832
833		check_state_space_version :- state_space_version(V),
834		(state_space_version_in_file(F) -> true ; F=0),
835		(V>F -> add_message(state_space,'Warning: saved state_space may be incompatible with current version: ',F:V) ; true).
836
837		% save all infos of state space (transitions, evaluated invariants, ...)
838		tcltk_save_state_space(File) :-
839		print('% saving full state space to: '), print(File),nl,
840		open(File,write,Stream,[encoding(utf8)]),
841		print_state_space(Stream),
842		close(Stream),
843		print_message(done).
844
845
846		:- use_module(tools_printing, [print_dynamic_fact/2,print_dynamic_pred/4]).
847		print_state_space(Stream) :-
848		state_space_version(V),
849		print_dynamic_fact(Stream,state_space_version_in_file(V)),
850		% TO DO: maybe also save some important preferences, and warn user and/or propose to adapt preferences ?
851		print_dynamic_pred(Stream,state_space,history,1),
852		print_dynamic_pred(Stream,state_space,forward_history,1),
853		print_dynamic_pred(Stream,state_space,op_trace_ids,1),
854		print_dynamic_pred(Stream,state_space,current_state_id,1),
855		print_dynamic_pred(Stream,state_space,current_options,1),
856		print_dynamic_pred(Stream,state_space,packed_visited_expression,2),
857		print_dynamic_pred(Stream,state_space,not_invariant_checked,1),
858		print_dynamic_pred(Stream,state_space,not_interesting,1),
859		print_dynamic_pred(Stream,state_space,max_reached_for_node,1),
860		print_dynamic_pred(Stream,state_space,time_out_for_node,3),
861		print_dynamic_pred(Stream,state_space,use_no_timeout,1),
862		print_dynamic_pred(Stream,state_space,transition,4),
863		print_dynamic_pred(Stream,state_space,transition_info,2),
864		print_dynamic_pred(Stream,state_space,operation_not_yet_covered,1),
865		print_dynamic_pred(Stream,state_space,state_error,3),
866		print_state_space_open_nodes(Stream),
867		print_stored_values(Stream),
868		get_counter(states,X),
869		write_term(Stream,saved_gennum_count(X),[quoted(true)]),write(Stream,'.'),nl(Stream).
870
871		saved_gennum_count(99999).
872
873		/* ---------------------- */
874		/* state space loading */
875		/* ---------------------- */
876
877		tcltk_load_state(File) :- state_space_clean_all,
878		print('Loading: '), print(File),nl,
879		user_consult_without_redefine_warning(File), % this will read in bind_skeleton/2, ..., next_value_id/1
880		check_state_space_version,
881		print('Generating open node info'),nl,
882		transfer_open_node_info,
883		print('Transfer state packing info'),nl,
884		transfer_state_packing_info,
885		print('Recomputing hash index'),nl,
886		recompute_all_hash,
887		(saved_gennum_count(X) -> reset_state_counter(X) ; true),
888		reset_processed_nodes_counter, % TO DO: restore or save it
889		reset_next_state_error_id_counter, % DITTO
890		print('Done'),nl,!.
891		tcltk_load_state(File) :-
892		add_error(tcltk_load_state,'Could not load state from file: ',File),
893		state_space_initialise.
894
895		:- dynamic not_all_z_saved/1, not_all_transitions_added_saved/1.
896		:- dynamic bind_skeleton/2, stored_value/2, stored_value_hash_to_id/2, next_value_id/1.
897
898		% transfer facts read into state_space into other modules:
899		transfer_open_node_info :- retract(not_all_z_saved(X)), %print(not_all_z(X)),nl,
900		assert_not_all_z(X),fail.
901		transfer_open_node_info :- retract(not_all_transitions_added_saved(X)),
902		assert_not_all_transitions_added(X),fail.
903		transfer_open_node_info.
904		% now for transferring to state_packing module info generated by print_stored_values
905		transfer_state_packing_info :- retract(bind_skeleton(X,Y)), %print(skel(X)),nl,
906		assertz(state_packing:bind_skeleton(X,Y)),fail.
907		transfer_state_packing_info :- retract(stored_value(X,Y)),
908		assertz(state_packing:stored_value(X,Y)),fail.
909		transfer_state_packing_info :- retract(stored_value_hash_to_id(X,Y)),
910		assertz(state_packing:stored_value_hash_to_id(X,Y)),fail.
911		transfer_state_packing_info :- retract(next_value_id(X)),
912		state_packing:set_next_value_id(X),fail.
913		transfer_state_packing_info.
914
915		recompute_all_hash :-
916		retractall(hash_to_id(_,_)),retractall(id_to_marker(_,_)),
917		retractall(hash_to_nauty_id(_,_)),
918	?	visited_expression(ID,StateTemplate),
919		state_space_exploration_modes:compute_hash(StateTemplate,Hash,Marker),
920		assertz(hash_to_id(Hash,ID)),
921		assertz(id_to_marker(ID,Marker)),
922		fail.
923		recompute_all_hash.
924
925		:- use_module(hashing,[my_term_hash/2]).
926		% generates a hash for the entire state space not depending on the order in which states where added
927		compute_full_state_space_hash(Hash) :-
928		%listing(hash_to_id/2), listing(packed_visited_expression/2),
929		findall(Hash,hash_to_id(Hash,_),ListOfHashCodes),
930		sort(ListOfHashCodes,SortedList),
931		my_term_hash(SortedList,Hash).
932		% TO DO: also provide transition hashes
933
934		:- use_module(tools_meta,[safe_on_exception/3]).
935		user_consult_without_redefine_warning(File) :-
936		get_set_optional_prolog_flag(redefine_warnings, Old, off),
937		get_set_optional_prolog_flag(single_var_warnings, Old2, off),
938		(safe_on_exception(Exc,
939		%consult(File), %
940		load_files([File], [load_type(source),compilation_mode(consult),encoding(utf8)]),
941		(nl,print('Exception occurred:'),print(Exc),nl,fail))
942		-> OK=true ; OK=false),
943		get_set_optional_prolog_flag(redefine_warnings, _, Old),
944		get_set_optional_prolog_flag(single_var_warnings, _, Old2),
945		OK=true.
946
947
948
949		execute_id_trace_from_current(ID,OpIDL,StateIDList) :-
950		current_state_id(CurID),
951		reverse([CurID|StateIDList],Rev),
952		Rev = [Dest|TRev], (Dest==ID -> true ; print(not_eq(Dest,ID)),nl),
953		retract(history(H)),
954		update_forward_history(OpIDL), % check if OpIDL conforms to forward history and keep it
955		append(TRev,H,NewH),
956		assertz(history(NewH)),
957		retract(op_trace_ids(OldTrace)),
958		reverse(OpIDL,NewTrace),
959		append(NewTrace,OldTrace,Trace),
960		assertz(op_trace_ids(Trace)),
961		retractall(current_state_id(_)),
962		assertz(current_state_id(ID)).
963		%execute_trace_to_node(OpL,StateIDList). /* <----- BOTTLENECK FOR LONG SEQUENCES */
964		%generate_trace([],Acc,Acc).
965		%generate_trace([OpTerm|T],Acc,Res) :-
966		% translate:translate_event(OpTerm,OpString),
967		% generate_trace(T,[action(OpString,OpTerm)|Acc],Res).
968
969		update_forward_history(TransitionIds) :-
970		(retract(forward_history(Forward)),
971		prune_forward_history(TransitionIds,Forward,NewForward)
972		-> assert(forward_history(NewForward))
973		; true).
974		% try and prune forward history if it matches operation trace
975		prune_forward_history([],ForwardHistory,ForwardHistory).
976		prune_forward_history([TransID|T],[forward(_,TransID)|TF],Res) :-
977		prune_forward_history(T,TF,Res).
978
979		try_set_trace_by_transition_ids(TransIds) :-
980		(set_trace_by_transition_ids(TransIds) -> true
981		; add_internal_error('Call failed:',set_trace_by_transition_ids(TransIds))).
982
983		set_trace_by_transition_ids(TransitionIds) :-
984		extract_history_from_transition_ids(TransitionIds,root,[],[],Last,History,OpTrace),
985		%visited_expression(Last,LastState,LastCond),
986		retractall(history(_)),
987		retractall(forward_history(_)), % TODO: we could try and recover a new forward history if transition ids match current history^forward history
988		update_forward_history(TransitionIds),
989		retractall(current_state_id(_)),
990		retractall(op_trace_ids(_)),
991		assertz(history(History)),
992		assertz(op_trace_ids(OpTrace)),
993		assertz(current_state_id(Last)).
994
995
996		extract_history_from_transition_ids([],CurrentState,History,Trace,CurrentState,History,Trace).
997		extract_history_from_transition_ids([TransId|Rest],CurrentState,AccHist,AccTrace,Last,History,Trace) :-
998		transition(CurrentState,_,TransId,DestState),!,
999		extract_history_from_transition_ids(Rest,DestState,[CurrentState|AccHist],
1000		[TransId|AccTrace],Last,History,Trace).
1001		extract_history_from_transition_ids([skip|Rest],CurrentState,AccHist,AccTrace,Last,History,Trace) :- !,
1002		extract_history_from_transition_ids(Rest,CurrentState,AccHist,AccTrace,Last,History,Trace).
1003		extract_history_from_transition_ids([TransId|_],CurrentState,_,_,_,_,_Trace) :-
1004		add_error(state_space,'Could not execute transition id: ', TransId:from(CurrentState)),fail.
1005
1006		% extend trace from current state
1007		extend_trace_by_transition_ids(TransitionIds) :-
1008		current_state_id(CurID),
1009		history(OldH), op_trace_ids(OldOT),
1010		extract_history_from_transition_ids(TransitionIds,CurID,OldH,OldOT,Last,History,OpTrace),
1011		retractall(history(_)), retractall(forward_history(_)),
1012		retractall(current_state_id(_)),
1013		retractall(op_trace_ids(_)),
1014		assertz(history(History)),
1015		assertz(op_trace_ids(OpTrace)),
1016		assertz(current_state_id(Last)).
1017
1018		/* --------------------------------- */
1019		:- dynamic max_nr_of_new_nodes/1.
1020
1021		% negative number or non-number signifies no limit
1022		set_max_nr_of_new_impl_trans_nodes(MaxNrOfNewNodes) :-
1023		retractall(max_nr_of_new_nodes(_)),
1024		(number(MaxNrOfNewNodes), MaxNrOfNewNodes>=0
1025		-> assertz(max_nr_of_new_nodes(MaxNrOfNewNodes))
1026		; true). % no need to store limit; we will explore as much as needed
1027
1028		get_max_nr_of_new_impl_trans_nodes(MaxNrOfNewNodes) :-
1029		(max_nr_of_new_nodes(Max) -> MaxNrOfNewNodes=Max; MaxNrOfNewNodes = 0).
1030
1031		% used e.g., in refinement or ltl checker
1032		impl_trans_term(From,ActionAsTerm,To) :-
1033		compute_transitions_if_necessary_saved(From),
1034	?	transition(From,ActionAsTerm,_TID,To).
1035
1036		% a variation also giving the transition id:
1037		impl_trans_id(From,ActionAsTerm,TransitionID,To) :-
1038		compute_transitions_if_necessary_saved(From),
1039	?	transition(From,ActionAsTerm,TransitionID,To).
1040
1041		impl_trans_term_all(From,Ops) :-
1042		compute_transitions_if_necessary_saved(From),
1043		findall(op(Id,ActionAsTerm,To),
1044		transition(From,ActionAsTerm,Id,To),
1045		Ops).
1046
1047		% true if e.g., a time-out occurred during computation of all transitions
1048		impl_trans_not_complete(From) :- max_reached_or_timeout_for_node(From).
1049
1050		compute_transitions_if_necessary_saved(From) :-
1051		catch(
1052		compute_transitions_if_necessary(From),
1053		error(forced_interrupt_error('User has interrupted the current execution'),_),
1054		user_interrupts:process_interrupted_error_message).
1055
1056		:- use_module(tcltk_interface,[compute_all_transitions_if_necessary/2]).
1057		compute_transitions_if_necessary(From) :-
1058		not_all_transitions_added(From),!,
1059		decrease_max_nr_of_new_nodes(From),
1060		compute_all_transitions_if_necessary(From,false).
1061		compute_transitions_if_necessary(_From).
1062
1063		decrease_max_nr_of_new_nodes(ID) :-
1064		retract(max_nr_of_new_nodes(Max)),!,
1065		( Max>0 ->
1066		NewMax is Max-1,
1067		assertz(max_nr_of_new_nodes(NewMax))
1068		; Max=0 -> NM is -1,
1069		assertz(max_nr_of_new_nodes(NM)),
1070		add_warning(state_space,'Maximum number of new nodes reached for CTL/LTL/refinement check, node id = ',ID),
1071		fail
1072		; % negative number: re-assert and fail
1073		assertz(max_nr_of_new_nodes(Max)),
1074		fail).
1075		decrease_max_nr_of_new_nodes(_). % no limit stored; just proceed
1076
1077		% will be called from TCL/TK side
1078		max_nr_of_new_nodes_limit_not_reached :-
1079		max_nr_of_new_nodes(N),N>0.
1080
1081		:- use_module(specfile,[b_or_z_mode/0, csp_mode/0, csp_with_bz_mode/0]).
1082		retract_open_node(NodeID) :- retract_open_node_and_update_processed_nodes(NodeID),
1083		(b_or_z_mode -> assertz(not_invariant_checked(NodeID)) ; true).
1084
1085		reset_processed_nodes_counter :- reset_counter(processed_nodes).
1086		%reset_processed_nodes_counter(Nr) :- set_counter(processed_nodes,Nr).
1087
1088		retract_open_node_and_update_processed_nodes(NodeID) :-
1089		retract_open_node_direct(NodeID),
1090		inc_processed.
1091
1092		inc_processed :-
1093		inc_counter(processed_nodes).
1094
1095		pop_id_from_front(ID) :- pop_id_from_front_direct(ID), inc_processed.
1096		pop_id_from_end(ID) :- pop_id_from_end_direct(ID), inc_processed.
1097	?	pop_id_oldest(ID) :- pop_id_oldest_direct(ID), inc_processed.
1098
1099
1100
1101		/* --------------------------------- */
1102
1103		% find initialised states; very similar to is_initial_state_id/1
1104		% but is used by ltl/ctl/sap
1105		% TO DO: merge these two variations of the same concept
1106
1107		:- use_module(specfile,[animation_mode/1]).
1108
1109		find_initialised_states(Init) :-
1110		animation_mode(Mode),
1111		( init_states_mode_cst_init(Mode) ->
1112		findall(I,find_init1(root,I,_),Init)
1113		; init_states_mode_one_step(Mode) ->
1114		next_states_from_root(Init)
1115		;
1116		fail).
1117
1118		% find trace to some initialised state
1119		find_trace_to_initial_state(Target,Trace) :- animation_mode(Mode),
1120	?	find_aux(Mode,Target,Trace).
1121		find_aux(Mode,Target,[root,Target]) :-
1122		init_states_mode_one_step(Mode).
1123		find_aux(Mode,Target,[root|Trace]) :-
1124		init_states_mode_cst_init(Mode),
1125	?	find_init1(root,Target,Trace).
1126
1127
1128		init_states_mode_cst_init(b).
1129		init_states_mode_cst_init(z).
1130		init_states_mode_cst_init(csp_and_b).
1131
1132		init_states_mode_one_step(csp).
1133		init_states_mode_one_step(cspm).
1134		init_states_mode_one_step(xtl).
1135		%init_states_mode_one_step(promela).
1136
1137		next_states_from_root(States) :-
1138		impl_trans_term_all(root,Ops),
1139		findall(S, member(op(_Id,_,S),Ops), States).
1140
1141		find_init1(Start,Init,Trace) :- Start==Init,!,Trace=[]. % usually called with Start=Init=root
1142		find_init1(Start,Init,[State|Rest]) :-
1143	?	impl_trans_term(Start,O,State),
1144	?	find_init2(O,State,Init,Rest).
1145		find_init2(O,Init,Init,[]) :-
1146		has_functor_and_maybe_tau(O,'$initialise_machine').
1147		find_init2(O,State,Init,Path) :-
1148		has_functor_and_maybe_tau(O,'$setup_constants'),
1149	?	find_init1(State,Init,Path).
1150		find_init2(start_cspm_MAIN,State,Init,Path) :-
1151	?	find_init1(State,Init,Path).
1152		find_init2(start_cspm(_Proc),State,Init,Path) :-
1153		find_init1(State,Init,Path).
1154
1155		% has_functor_and_maybe_tau(Term,Functor)
1156		% checks if Term has the form "Functor(...)" or "tau(Functor(...))"
1157		% this is used for CSP||B specification where the initialisation is wrapped with
1158		% in a tau operator
1159		has_functor_and_maybe_tau(tau(Term),Functor) :-
1160		has_functor_and_maybe_tau(Term,Functor),!.
1161		has_functor_and_maybe_tau(Term,Functor) :-
1162		functor(Term,Functor,_).
1163
1164		% compute how far the state is from the root node using back_edge markers (if available)
1165		try_compute_depth_of_state_id(root,R) :- !, R=0.
1166		try_compute_depth_of_state_id(Node,Depth) :- id_back_edge(Node,Depth,_Back).
1167
1168		% optional registering of back_edges: to quickly find trace from root and to computed depth/diameter
1169		register_back_edge(ID,FromID) :-
1170		try_compute_depth_of_state_id(FromID,D),!,
1171		D1 is D+1,
1172		assertz(id_back_edge(ID,D1,FromID)).
1173		register_back_edge(ID,FromID) :- write(cannot_store_back_edge(ID,FromID)),nl.
1174
1175		/* --------------------------------- */
1176
1177		%
1178		% Code to compute equivalence classes
1179		% using the standard DFA minimization algorithm
1180
1181		:- dynamic equivalent/2.
1182		% state_space:compute_equivalence_classes
1183		:- public compute_equivalence_classes/0.
1184
1185		compute_equivalence_classes :- init_equi,
1186		split_equivalence_classes,nl,
1187		print_equi.
1188
1189		print_equi :- state_space:equivalent(A,B), visited_expression(A,State),
1190		visited_expression(B,StateB),
1191		nl,
1192		print(A), print(' : '), print(State),nl,
1193		print(B), print(' : '), print(StateB),nl,fail.
1194		print_equi.
1195
1196		init_equi :- retractall(equivalent(_,_)),
1197		packed_visited_expression(ID,_State),
1198		\+ not_all_transitions_added(ID),
1199		findall(Action,transition(ID,Action,_,_),List),
1200		packed_visited_expression(ID2,_S2), ID2 @> ID,
1201		\+ not_all_transitions_added(ID2),
1202		findall(Action,transition(ID2,Action,_,_),List),
1203		assertz(equivalent(ID,ID2)), % they have the same signature
1204		%print(equivalent(ID,ID2)),nl,
1205		fail.
1206		init_equi :- print(finished_initialising),nl.
1207
1208		split_equivalence_classes :- retractall(echange),
1209		equivalent(ID1,ID2),
1210		transition(ID1,A,_,Dest1),
1211		transition(ID2,A,_,Dest2),
1212		\+ check_equi(Dest1,Dest2),
1213		retract(equivalent(ID1,ID2)), % splitting class
1214		% print(diff(ID1,ID2, A, Dest1, Dest2)),nl,
1215		assert_echange,
1216		fail.
1217		split_equivalence_classes :- echange -> split_equivalence_classes ; true.
1218
1219		:- dynamic echange/0.
1220		assert_echange :- echange -> true ; assertz(echange),print('.'),flush_output.
1221
1222		check_equi(A,B) :- A=B -> true ; A @<B -> equivalent(A,B) ; equivalent(B,A).
1223
1224		/*
1225		% benchmark how much time it takes to copy the state space state_space:bench_state_space.
1226		bench_state_space :-
1227		statistics(walltime,_),
1228		(state_space:packed_visited_expression(ID,S), assertz(pve(ID,S)),fail ; true),
1229		statistics(walltime,[_,Delta]), format('Time to copy packed_visited_expression: ~w ms~n',[Delta]),
1230		(state_space:transition(A,B,C,D), assertz(tr(A,B,C,D)),fail ; true),
1231		statistics(walltime,[_,Delta2]), format('Time to copy transition: ~w ms~n',[Delta2]),
1232		(state_packing:stored_value(A,B), assertz(sv(A,B)),fail ; true),
1233		(state_packing:stored_value_hash_to_id(A,B), assertz(svhi(A,B)),fail ; true),
1234		statistics(walltime,[_,Delta3]), format('Time to copy stored_value: ~w ms~n',[Delta3]).
1235		*/
1236
1237		:- public portray_state_space/0.
1238		portray_state_space :- packed_visited_expression(ID,S), functor(S,F,N),
1239		format('State ~w : ~w/~w~n',[ID,F,N]), fail.
1240		portray_state_space :- transition(ID,Action,TransID,DestID),
1241		format(' ~w: ~w -- ~w --> ~w~n',[TransID,ID,Action,DestID]),fail.
1242		portray_state_space.
1243
1244		bench_state_space :- statistics(walltime,[W1,_]),
1245		(packed_visited_expression(_,_), fail ; true),
1246		statistics(walltime,[W2,_]), T1 is W2-W1,
1247		format('Time to inspect all states: ~w ms walltime~n',[T1]),
1248		(visited_expression(_,_), fail ; true),
1249		statistics(walltime,[W3,_]), T2 is W3-W2,
1250		format('Time to inspect and unpack all states: ~w ms walltime~n',[T2]),
1251		(transition(_,_,_,_), fail ; true),
1252		statistics(walltime,[W4,_]), T3 is W4-W3,
1253		format('Time to inspect all transitions: ~w ms walltime~n',[T3]),
1254		(visited_expression(_,E), my_term_hash(E,_), fail ; true),
1255		statistics(walltime,[W5,_]), T4 is W5-W4,
1256		format('Time to inspect, unpack and hash all states: ~w ms walltime~n',[T4]).
1257
1258		% ----------------------------
1259		% COUNTER EXAMPLE MANAGEMENT
1260
1261		% store counter example nodes and transition ids; used by LTL model checking for example
1262
1263
1264		:- dynamic counterexample_node/1.
1265		:- dynamic counterexample_op/1.
1266
1267		add_counterexample_node(NodeID) :- assertz(counterexample_node(NodeID)).
1268		add_counterexample_op(TransID) :-
1269		(counterexample_op(TransID) -> true ; assertz(counterexample_op(TransID))).
1270
1271
1272		reset_counterexample :-
1273		retractall(counterexample_node(_)),
1274		retractall(counterexample_op(_)).
1275
1276		:- register_event_listener(play_counterexample,reset_counterexample,
1277		'Reset marked nodes from previous counterexamples.').
1278
1279		set_counterexample_by_transition_ids(TransIds) :-
1280		set_trace_by_transition_ids(TransIds),
1281		maplist(add_counterexample_op,TransIds),
1282		extract_history_from_transition_ids(TransIds,root,[],[],_Last,History,_OpTrace),
1283		maplist(add_counterexample_node,History).