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(debug,[debug_println/1, debug_println/2]).
115		%:- use_module(state_space_exploration_modes,[compute_hash/3]).
116
117		:- use_module(extension('counter/counter'),
118		[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]).
119
120		:- use_module(module_information).
121		:- module_info(group,state_space).
122		:- module_info(description,'This module keeps track of the visited states by the animator/model checker.').
123
124		% ----------------------------------
125
126		:- load_files(library(system), [when(compile_time), imports([environ/2])]).
127		:- if((environ(prob_myheap,false) ; \+ predicate_property(load_foreign_resource(_), _))).
128		:- use_module(state_space_open_nodes). %% comment in to use only Prolog datastructures
129		:- else.
130		:- use_module(state_space_open_nodes_c). %% comment in to use C++ multimap queue; can make use of HEURISTIC_FUNCTION
131		:- endif.
132
133		% ----------------------------------
134
135		get_state_space_stats(NrNodes,NrTransitions,ProcessedNodes) :-
136		get_counter(states,N), NrNodes is N+1,
137		get_counter(transitions,NrTransitions),
138		get_counter(processed_nodes,ProcessedNodes).
139
140		get_state_space_stats(NrNodes,NrTransitions,ProcessedNodes,IgnoredNodes) :-
141		get_state_space_stats(NrNodes,NrTransitions,ProcessedNodes),
142		get_counter(not_interesting_nodes,IgnoredNodes).
143
144		gen_new_state_id(Nr) :-
145		inc_counter(states,N1), Nr is N1-1. % only one C call
146		%get_counter(states,Nr), inc_counter(states).
147		reset_state_counter :- reset_counter(states).
148		reset_state_counter(Nr) :- set_counter(states,Nr).
149
150		get_state_id_trace(StateIds) :-
151		history(History),
152		current_state_id(CurID),
153		reverse([CurID|History],StateIds).
154
155		get_current_predecessor_state_id(PriorID) :-
156		history([PriorID|_]).
157
158		:- dynamic history/1.
159		history([]).
160
161
162		:- dynamic forward_history/1.
163
164		:- dynamic current_state_id/1.
165		current_state_id(root).
166		/* INITIAL STATE, third arg: clp(fd) constraints as generated
167		by fd_copy_term */
168
169		current_expression(ID,State) :- current_state_id(ID),
170		visited_expression(ID,State).
171		current_packed_expression(ID,State) :- current_state_id(ID),
172		packed_visited_expression(ID,State).
173
174		:- use_module(specfile,[state_corresponds_to_initialised_b_machine/1,
175		state_corresponds_to_fully_setup_b_machine/1,
176		state_corresponds_to_set_up_constants/1]).
177		current_state_corresponds_to_initialised_b_machine :-
178		current_packed_expression(_,PS), unpack_state_top_level(PS,TLState),
179		state_corresponds_to_initialised_b_machine(TLState).
180		visited_state_corresponds_to_initialised_b_machine(ID) :-
181		packed_visited_expression(ID,PS), unpack_state_top_level(PS,TLState),
182		state_corresponds_to_initialised_b_machine(TLState).
183
184		current_state_corresponds_to_fully_setup_b_machine :-
185		current_packed_expression(_,PS), unpack_state_top_level(PS,TLState),
186		state_corresponds_to_fully_setup_b_machine(TLState).
187
188		current_state_corresponds_to_setup_constants_b_machine :-
189		current_packed_expression(_,PS), unpack_state_top_level(PS,TLState),
190		state_corresponds_to_set_up_constants(TLState).
191
192		visited_state_corresponds_to_setup_constants_b_machine(ID) :-
193		packed_visited_expression(ID,PS), unpack_state_top_level(PS,TLState),
194		state_corresponds_to_set_up_constants(TLState).
195
196		:- dynamic current_options/1.
197		current_options([]).
198
199		set_current_options(Options) :-
200		retractall( current_options(_) ),
201		assertz( current_options(Options) ).
202
203		:- dynamic packed_visited_expression/2.
204		%packed_visited_expression(v_0,true).
205
206		:- use_module(state_packing).
207
208		retract_visited_expression(ID,State) :- retract(packed_visited_expression(ID,PState)),
209		unpack_state(PState,State).
210
211		retractall_visited_expression(ID) :- retractall(packed_visited_expression(ID,_)).
212
213		state_space_packed_add(Id,PackedTerm) :- assertz(packed_visited_expression(Id,PackedTerm)).
214
215		state_space_add(Id,Term) :-
216		(pack_state(Term,PackedTerm) -> assertz(packed_visited_expression(Id,PackedTerm))
217		; add_internal_error('State packing failed: ',pack_state(Term,_)),
218		assertz(packed_visited_expression(Id,Term))).
219
220		% deprecated:
221		visited_expression(ID,State,true) :- visited_expression(ID,State).
222		% not call(CurBody); for the moment we always have true as last argument
223
224	?	visited_expression(A,B) :- packed_visited_expression(A,PB),
225		(unpack_state(PB,R) -> B=R ; add_internal_error('Unpacking state failed: ',unpack_state(PB,R)),R=A).
226
227		%visited_expression_id(A) :- packed_visited_expression(A,_). % avoid unpacking state
228		% even better: not to look up fact at all to avoid constructing state term, this is done below:
229		:- use_module(library(between),[between/3]).
230		visited_expression_id(ID) :- number(ID),!, ID>=0, get_counter(states,N), ID<N.
231		visited_expression_id(ID) :- ID==root,!.
232		visited_expression_id(root).
233	?	visited_expression_id(Nr) :- Nr \== root, get_counter(states,N), N1 is N-1, between(0,N1,Nr).
234
235		% given a hash and a packed state: find ID (fail if does not exist)
236		find_hashed_packed_visited_expression(Hash,PackedState,ID) :-
237		hash_to_id(Hash,ID),
238		(packed_visited_expression(ID,PackedState)
239		-> true /* warning: may instantiate State if not ground */
240		; functor(PackedState,concrete_constants,1),
241		preference(maxNrOfInitialisations,Max), Max =< 4
242		-> debug_println(19,hash_collision_for_constants(Hash,ID)),fail
243		% this is not too bad if maxNrOfInitialisations small;
244		% can happen due to depth limit in term_depth_hash in compute_hash
245		; write(hash_collision(Hash,ID)),nl,fail
246		).
247
248
249		:- dynamic not_invariant_checked/1.
250		set_invariant_checked(ID) :- %print(inv_checked(ID)),nl,
251		retract(not_invariant_checked(ID)).
252
253		invariant_not_yet_checked(ID) :-
254		not_all_transitions_added(ID) ; /* assumption: if not all transitions added then we haven't checked invariant yet */
255		not_invariant_checked(ID) ;
256		not_interesting(ID). % assumption: if a node is marked as not interesting it will not be examined
257
258		% difference with invariant_not_yet_checked: not interesting nodes not reported and cannot be backtracked
259		invariant_still_to_be_checked(ID) :-
260		(not_all_transitions_added(ID) -> true ; not_invariant_checked(ID) -> true).
261
262		:- dynamic not_interesting/1.
263		%not_interesting(v_0).
264
265		:- dynamic max_reached_for_node/1.
266		/* true if not all outgoing transistions were computed due to the limit
267		on the number of operations/initialisations computed */
268		:- dynamic time_out_for_node/3, use_no_timeout/1, time_out_for_invariant/1, time_out_for_assertions/1.
269
270		time_out_for_node(ID) :- (var(ID) -> visited_expression_id(ID) ; true),
271		(time_out_for_node(ID,_,_) -> true ; fail).
272
273		:- dynamic transition/4.
274		%transition(v_0,a,1,v_1).
275
276		store_transition(Org,Action,Dest,Id) :-
277		%get_counter(transitions,Id), inc_counter(transitions),
278		inc_counter(transitions,Id1), Id is Id1-1, % only one C call
279		assertz(transition(Org,Action,Id,Dest)).
280
281	?	deadlocked_state(Origin) :- \+ any_transition(Origin,_,_).
282
283		is_concrete_constants_state_id(ID) :-
284	?	transition(root,_,ID),
285		packed_visited_expression(ID,concrete_constants(_)).
286
287		% check if we have multiple constant setups
288		multiple_concrete_constants_exist :-
289	?	is_concrete_constants_state_id(ID),
290	?	is_concrete_constants_state_id(ID2), ID2 \= ID,!.
291
292
293		is_initial_state_id(InitialStateID) :-
294		transition(root,_,State),
295		packed_visited_expression(State,P),
296		(P = concrete_constants(_) % also covers '$partial_setup_constants'
297		-> state_space:transition(State,_,InitialStateID)
298		; InitialStateID=State).
299
300		% get the constants for a state (if there are constants), avoid unpacking variables
301		get_constants_state_for_id(ID,CS) :- get_constants_state_for_id(ID,[],CS).
302		get_constants_state_for_id(ID,Opts,ConstantsState) :-
303		packed_visited_expression(ID,PState),
304		unpack_state_top_level(PState,TLState),
305		(TLState = const_and_vars(CID,_) -> get_constants_state_for_id(CID,[],ConstantsState)
306		; unpack_state(PState,UPState),
307		(UPState = concrete_constants(CS) -> ConstantsState=CS
308		; UPState = [_|_], member(allow_variable_list,Opts),
309		ConstantsState=UPState,
310		% could be that we have a state where constants and variables are mixed in a single list
311		% e.g., ProB2's FindStateCommand does currently not create new intermediate constant states
312		add_message(get_constants_state_for_id,'State is a list of bindings and has no reference to a constant valuation: ',ID)
313		)
314		).
315
316		% get the state id for associated constants state for a state (if there are constants)
317		get_constants_state_id_for_id(ID,CstID) :-
318		packed_visited_expression(ID,PState),
319		unpack_state_top_level(PState,TLState),
320		get_constants_id_for_id_aux(TLState,ID,CstID).
321		get_constants_id_for_id_aux(concrete_constants(_),ID,ID).
322		get_constants_id_for_id_aux(const_and_vars(ID,_),_,ID).
323
324		get_variables_state_for_id(ID,VarState) :-
325		visited_expression(ID,State),
326		get_vars_aux(State,VarState).
327		%get_vars_aux(concrete_constants(ConstantsState),[]).
328		get_vars_aux(const_and_vars(_,Vars),State) :- !, State=Vars.
329		get_vars_aux([],[]).
330		get_vars_aux([H|T],[H|T]).
331
332		% check if there is a unique constants state:
333		try_get_unique_constants_state(ConstantsState) :-
334		transition(root,_,_TransID,DestID),
335		\+ (transition(root,_,_,DestID2), DestID2 \= DestID), % no other transition exists
336		\+ max_reached_or_timeout_for_node(root),
337		DestID \= root, % DestID=root should never happen
338		get_constants_state_for_id(DestID,ConstantsState).
339
340		% returns id of constants state for a state (if it exists)
341		get_constants_id_for_state_id(ID,ConstID) :-
342		packed_visited_expression(ID,'$cst_vars'(ConstID,_)).
343
344	?	any_transition(Origin,TransID,Destination) :- transition(Origin,_,TransID,Destination).
345
346	?	transition(Origin,Action,Destination) :- transition(Origin,Action,_TransID,Destination).
347
348		:- dynamic transition_info/2.
349		store_transition_infos([],_TransId).
350		store_transition_infos([Info|Irest],TransId) :-
351		store_transition_info(Info,TransId),
352		store_transition_infos(Irest,TransId).
353		store_transition_info(Info,TransId) :- %print(info(Info,TransId)),nl,
354		(keep_transition_info(Info)
355		-> assertz(transition_info(TransId,Info))
356		; true).
357
358		% Do not store path info by default
359		keep_transition_info(path(_)) :- !, preference(eventtrace,true).
360		keep_transition_info(eventtrace(_)) :- !,preference(eventtrace,true).
361		keep_transition_info(event(_)) :- !,preference(store_event_transinfo,true).
362		keep_transition_info(_). % store everything else
363
364		reset_transition_store :-
365		retractall(transition(_,_,_,_)),
366		retractall(transition_info(_,_)),
367		reset_counter(transitions),
368		reset_counterexample.
369
370		/*
371		Version with packing of transitions:
372		store_transition(Org,Action,Dest,Id) :-
373		retract(transition_counter(Id)),
374		NewId is Id+1,
375		assertz(transition_counter(NewId)),
376		Action =.. [ActionName|Parameters],
377		pack_values(Parameters,PackedParameters),
378		assertz(packed_transition(Org,ActionName,PackedParameters,Id,Dest)).
379
380		transition(Origin,Action,TransID,Destination) :- nonvar(Action),!,
381		Action =.. [ActionName|Parameters],
382		packed_transition(Origin,ActionName,PackedParameters,TransID,Destination),
383		unpack_values(PackedParameters,Parameters).
384		transition(Origin,Action,TransID,Destination) :-
385		packed_transition(Origin,ActionName,PackedParameters,TransID,Destination),
386		unpack_values(PackedParameters,Parameters),
387		Action =.. [ActionName|Parameters].
388		any_transition(Origin,TransID,Destination) :- packed_transition(Origin,_,_,TransID,Destination).
389		*/
390
391		% compute out-degree of a node
392		out_degree(ID,OutDegree) :- findall(0, transition(ID,_,_,_), L), length(L,OutDegree).
393
394		operation_name_not_yet_covered(OpName) :- operation_not_yet_covered(OpName).
395
396
397		get_operation_name_coverage_infos(PossibleNr,FeasibleNr,UncovNr,UncoveredList) :-
398		findall(ON, specfile:get_possible_event(ON), Possible), length(Possible,PossibleNr),
399		findall(OF, specfile:get_feasible_event(OF), Feasible), length(Feasible,FeasibleNr),
400		findall(OpName, state_space: operation_name_not_yet_covered(OpName), UncoveredList),
401		length(UncoveredList,UncovNr).
402
403
404		:- dynamic operation_not_yet_covered/1.
405		%operation_not_yet_covered(b).
406
407		:- use_module(probsrc(debug),[formatsilent/2]).
408		mark_operation_as_covered(OpName) :-
409		(retract(operation_not_yet_covered(OpName))
410		-> (preferences:get_preference(provide_trace_information,true)
411		-> formatsilent('Covered ~w~n',[OpName])
412		; true),
413	?	(operation_not_yet_covered(_) -> true ; formatsilent('~nALL OPERATIONS COVERED~n',[]))
414		; true
415		).
416
417
418		:- use_module(bmachine,[b_top_level_operation/1]).
419		:- use_module(probcspsrc(haskell_csp),[channel/2]).
420		initialise_operation_not_yet_covered :- retractall(operation_not_yet_covered(_)),
421		b_or_z_mode,
422	?	b_top_level_operation(Name),
423		% b_get_machine_operation(Name,_,Par,_), length(Par,Arity), functor(Op,Name,Arity),
424		% Note: no '-->' added
425		assertz(operation_not_yet_covered(Name)),
426		fail.
427		/* Missing: treat operations with return values */
428		initialise_operation_not_yet_covered :- csp_mode, \+ csp_with_bz_mode,
429		channel(Name,_),
430		assertz(operation_not_yet_covered(Name)),
431		fail.
432		initialise_operation_not_yet_covered.
433
434		state_error_exists :- state_error(_,_,_),!.
435		:- dynamic state_error/3.
436
437		%state_error([],invariant_violated).
438
439		reset_next_state_error_id_counter :- reset_counter(next_state_error_id).
440		:- use_module(tools_printing, [print_error/1, format_error_with_nl/2]).
441		:- use_module(error_manager,[print_error_span/1]).
442		store_state_error(State,Error,Id) :- state_error(State,Id,Error),!. % do not store identical error twice
443		store_state_error(State,Error,Id) :-
444		%retract( next_state_error_id(Id) ),
445		inc_counter(next_state_error_id,Id),
446		% tools_printing:print_term_summary(Error),nl, tools_printing:nested_print_term(Error),nl,
447		assertz( state_error(State,Id,Error) ).
448		store_error_for_context_state(Error,Id) :-
449		( context_state(State,Errs) ->
450		(Errs<25
451		-> store_state_error(State,Error,Id), E1 is Errs+1,
452		%assertz(context_state(State,E1))
453		set_context_number_of_errors(E1)
454		; store_state_error(State,max_state_errors_reached(25),Id)
455		)
456		;
457		add_internal_error('No known context when calling store_error_for_context_state: ',store_error_for_context_state(Error,Id)),
458		fail).
459
460		% check if we already have a certain type of error in the current context state
461		abort_error_exists_in_context_state(ErrType) :- get_current_context_state(State),
462		Error = abort_error(ErrType,_Msg,_Term,_Pos),
463		state_error(State,_Id,Error).
464
465		% copy current errors from error_manager to state errors
466		copy_current_errors_to_state(StateID,Context) :-
467		% error_manager:logged_error(Source,ErrMsg,_Context,Span), % will not retract
468		error_manager:get_error_with_span(Source,ErrMsg,Span), % will retract
469		store_state_error(StateID,abort_error(Source,ErrMsg,'',span_context(Span,Context)),SID),
470		% TO DO: use other error class
471		debug_println(stored(Source,SID,_Context,ErrMsg)),
472		fail.
473		copy_current_errors_to_state(_,_).
474
475		store_abort_error_for_context_state_if_possible(ErrType,Msg,Term,Span) :-
476		%print(store(Msg,Term,Span)),nl,
477		( get_current_context_state(State) ->
478		error_manager:get_error_context(Context),
479		(abort_error_for_same_location_exists(State,Id1,ErrType,Msg,Span),
480		abort_error_for_same_location_exists(State,Id2,ErrType,Msg,Span),
481		Id2>Id1
482		-> /* two errors of same type, for same state and same source location exists */
483		/* TO DO: maybe merge state errors */
484		simplify_span(Span,Span1),
485		compress_span(Span1,Span2),
486		store_state_error(State,abort_error(ErrType,'Further identical errors occurred (not stored !)',Term,span_context(Span2,Context)),_)
487		;
488		format_error_with_nl('! An error occurred in state ~w: ~w !',[State,ErrType]),
489		% usual errors: precondition_error, while_invariant_violation, while_variant_error,
490		% assert_error, well_definedness_error, card_overflow_error
491		print_error(Msg),
492		print_error_term(Term,Span),
493		% print_error(context_state_id(State)), % printed by print_error_context
494		print_error_context,
495		(debug_mode(on),visited_expression(State,S) -> translate:translate_bstate(S,O),print_error(O) ; true),
496		compress_span(Span,Span2),
497		print_error_span(Span2),
498		store_state_error(State,abort_error(ErrType,Msg,Term,span_context(Span2,Context)),_)
499		),
500		(add_new_event_in_error_scope(abort_error(ErrType)) -> true ; true), % should we use well_definedness_error?
501		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)
502		; % no current context_state exists:
503		compress_span(Span,Span2),
504		add_error(ErrType,Msg,Term,Span2)
505		).
506
507
508		:- use_module(bsyntaxtree, [find_identifier_uses/3]).
509		compress_span(span_context(Span,C),span_context(CS,C)) :- !,
510		compress_span(Span,CS).
511		compress_span(pos_context(Span1,C,Span2),pos_context(CS1,C,CS2)) :- !,
512		compress_span(Span1,CS1),
513		compress_span(Span2,CS2).
514		compress_span(span_predicate(Pred,LS,S),Res) :- find_identifier_uses(Pred,[],Ids),
515		sort(Ids,SIds),
516		filter_state(LS,SIds,FLS),
517		filter_state(S,SIds,FS), % TODO: do we need to store the global state? we can reconstruct it ?
518		% format('Compressed span_predicate (~w)~n',[Ids]),
519		!,
520		Res = span_predicate(Pred,FLS,FS).
521		compress_span(S,S).
522		% avoid storing large useless values
523		% TO DO: probably we should stop storing spans when a certain threshold of number of errors is reached
524
525
526		:- use_module(library(ordsets),[ord_member/2]).
527		filter_state([],_,[]).
528		filter_state([bind(ID,L)|T],Vars,Res) :-
529		(ord_member(ID,Vars) -> Res = [bind(ID,L)|RT] ; Res=RT),
530		filter_state(T,Vars,RT).
531
532
533		:- use_module(translate, [translate_error_term/3]).
534		print_error_term(T,S) :- (var(T);var(S)),!,
535		print_error('### VARIABLE error term or span:'), print_error(print_error_term(T,S)).
536		print_error_term(Term,Span) :- translate_error_term(Term,Span,S),
537		(S='' -> true ; print_error(S)).
538
539		abort_error_for_same_location_exists(State,Id,ErrType,Msg,Span) :-
540		state_error(State,Id,abort_error(ErrType,Msg,_Term2,span_context(Span2,_Ctxt2))),
541		same_span_location(Span2,Span).
542		% should be moved to error_manager ?
543		same_span_location(span_context(Span1,C),span_context(Span2,C)) :- !, same_span_location(Span1,Span2).
544		same_span_location(pos_context(Span1,C,_),pos_context(Span2,C,_)) :- !,
545		same_span_location(Span1,Span2). % should we check second span?
546		same_span_location(span_predicate(Pred1,_,_),span_predicate(Pred2,_,_)) :- !,Pred1=Pred2.
547		same_span_location(X,X).
548
549		:- dynamic saved_nested_context_state/2.
550		save_nested_context_state(_S) :-
551		bb_get(state_space_context_state,ID),
552		bb_get(state_space_context_errors,Errs),!,
553		%print(saving_context_state(_S,ID,Errs)),nl,
554		asserta(saved_nested_context_state(ID,Errs)).
555		save_nested_context_state(_).
556
557		% actually pops context state
558		clear_context_state :-
559		retract(saved_nested_context_state(ID,Errs)),!, %print(restoring_nested(ID,Errs)),nl,
560		bb_put(state_space_context_state,ID),
561		bb_put(state_space_context_errors,Errs).
562		clear_context_state :-
563		(bb_delete(state_space_context_state,_) -> true ; true).
564		%(retract(context_state(_,_)) -> true ; true). % retractall seems to be slowing down with use
565
566		% Note: Each Prolog module maintains its own blackboard for bb_get/bb_put
567		context_state(ID,Errs) :-
568		bb_get(state_space_context_state,ID), bb_get(state_space_context_errors,Errs).
569
570		% sets a new context state; pushing the previous one if necessary
571		set_context_state(State) :- %print(set_id(State)),nl,
572		save_nested_context_state(State),
573		bb_put(state_space_context_state,State),
574		bb_put(state_space_context_errors,0).
575
576		set_context_state(State,_Context) :- % Context can be used for debugging later
577		set_context_state(State).
578
579		% update current context state, without storing nested states
580		update_context_state(State) :-
581		bb_put(state_space_context_state,State),
582		bb_put(state_space_context_errors,0).
583
584		get_current_context_state(ID) :- bb_get(state_space_context_state,ID).
585		%get_current_context_state(ID) :- context_state(ID,_).
586
587		set_context_number_of_errors(Errs) :- bb_put(state_space_context_errors,Errs).
588
589		retractall_invariant_violated(State) :-
590		retractall(state_error(State,_,invariant_violated)).
591		invariant_violated(State) :-
592		state_error(State,_,invariant_violated).
593		set_invariant_violated(State) :-
594		( invariant_violated(State) -> true
595		; time_out_for_invariant(ID) -> print('Timeout for node: '), print(ID),nl,
596		print('Not setting invariant violation status'),nl
597		; store_state_error(State,invariant_violated,_)
598		).
599
600		%:- set_invariant_violated([]). % why is this ??
601
602
603		:- dynamic hash_to_id/2.
604		:- dynamic id_to_marker/2.
605		:- dynamic id_back_edge/3. % optional facts to keep track where a state was constructed from
606
607		:- dynamic hash_to_nauty_id/2. % used in nauty mode to map nauty id's to hash values
608
609		:- dynamic specialized_inv/2. /* stores whether for a node a specialized invariant
610		version could be computed */
611
612		% :- dynamic reuse_operation/4. /* when for a state and given operation name we can reuse the operation computed for another state */
613		% used to be used for OPERATION_REUSE TRUE
614
615		:- use_module(hashing).
616		state_space_startup :- % call once at startup to ensure all counters exist
617		counter_init,
618		new_counter(states), new_counter(processed_nodes), new_counter(transitions),
619		new_counter(next_state_error_id),
620		new_counter(not_interesting_nodes),
621		reset_open_ids. % also calls myheap init
622		state_space_initialise :- counter_init, reset_gennum, reset_gensym,
623		new_counter(states), new_counter(processed_nodes), new_counter(transitions),
624		new_counter(next_state_error_id), new_counter(not_interesting_nodes),
625		reset_state_counter, reset_processed_nodes_counter, reset_next_state_error_id_counter,
626		retractall_visited_expression(_),
627		reset_open_ids,
628		reset_stored_values, % state_packing
629		retractall(not_invariant_checked(_)),
630		reset_not_interesting,
631		retractall(max_reached_for_node(_)),
632		retractall(time_out_for_node(_,_,_)),
633		retractall(time_out_for_invariant(_)),
634		retractall(time_out_for_assertions(_)),
635		retractall(use_no_timeout(_)),
636		retractall(state_error(_,_,_)),
637		clear_context_state,
638		reset_transition_store,
639		retractall(operation_not_yet_covered(_)),
640		retractall(hash_to_id(_,_)),
641		retractall(id_back_edge(_,_,_)),
642		retractall(hash_to_nauty_id(_,_)),
643		retractall(id_to_marker(_,_)),
644		retractall(specialized_inv(_,_)),
645		%retractall(reuse_operation(_,_,_,_)),
646		state_space_add(root,root),
647		add_id_at_front(root),
648		my_term_hash(root,RootHash),
649		assertz(hash_to_id(RootHash,root)),
650		%assertz(not_invariant_checked(root)),
651		state_space_reset.
652
653		:- use_module(eventhandling,[register_event_listener/3]).
654		:- register_event_listener(startup_prob,state_space_startup,
655		'Initialise Statespace Counters.').
656		:- register_event_listener(reset_specification,state_space_initialise,
657		'Reset Statespace.').
658		:- register_event_listener(change_of_animation_mode,state_space_initialise,
659		'Reset Statespace.').
660		:- register_event_listener(specification_initialised,initialise_operation_not_yet_covered,
661		'Init coverage info.').
662		:- register_event_listener(reset_prob,state_space_initialise,
663		'Reset Statespace.').
664
665		/* A version of reset which checks how much memory is used by each fact */
666		/* state_space:init_with_stats */
667		state_space_initialise_with_stats :-
668		reset_gennum, reset_gensym, reset_state_counter, reset_processed_nodes_counter,
669		reset_next_state_error_id_counter,
670		retract_open_ids_with_statistics,
671		retract_with_statistics(state_space,[packed_visited_expression(_,_),
672		not_invariant_checked(_),
673		not_interesting(_),
674		max_reached_for_node(_),
675		time_out_for_node(_,_,_),
676		time_out_for_invariant(_),
677		time_out_for_assertions(_),
678		use_no_timeout(_),
679		state_error(_,_,_),
680		transition(_,_,_,_),
681		transition_info(_,_),
682		operation_not_yet_covered(_),
683		hash_to_id(_,_),
684		hash_to_nauty_id(_,_),
685		id_to_marker(_,_),
686		specialized_inv(_,_),
687		%reuse_operation(_,_,_,_),
688		history(_), forward_history(_), op_trace_ids(_)]),
689		reset_not_interesting,
690		retract_stored_values_with_statistics,
691		clear_context_state,
692		reset_transition_store,
693		state_space_add(root,root),
694		add_id_at_front(root),
695		%assertz(not_invariant_checked(root)),
696		state_space_reset,
697		initialise_operation_not_yet_covered.
698
699
700
701		:- dynamic op_trace_ids/1.
702		reset_trace :- retractall(op_trace_ids(_)), assertz(op_trace_ids([])).
703		get_action_trace(T) :- trace(T).
704		get_action_term_trace(PT) :- get_action_trace_with_limit(0,T), project_on_action_term(T,PT).
705		trace(Trace) :- get_action_trace_with_limit(500,Trace).
706		get_action_trace_with_limit(Limit,Trace) :-
707		op_trace_ids(IDT), reverse(IDT,RIDT),
708		extract_trace_from_transition_ids(RIDT,root,Limit,[],Trace).
709
710		reset_op_trace_ids :- retractall(op_trace_ids(_)), assertz(op_trace_ids([])).
711		add_to_op_trace_ids(OpID) :- retract(op_trace_ids(OpIDS)), assertz(op_trace_ids([OpID|OpIDS])).
712		remove_from_op_trace_ids(OpID) :- retract(op_trace_ids(OpIDS)),
713		(OpIDS = [R|Rest]
714		-> assertz(op_trace_ids(Rest)), OpID = R
715		; assertz(op_trace_ids(OpIDS)), fail).
716
717		% translate a list of transition ids (from root) into a list of operation terms
718		extract_term_trace_from_transition_ids(TransIDListFromRoot,Trace) :-
719		extract_trace_from_transition_ids(TransIDListFromRoot,root,0,[],ActionTrace),
720		reverse_and_project_on_action_term(ActionTrace,[],Trace).
721
722		reverse_and_project_on_action_term([],A,A).
723		reverse_and_project_on_action_term([action(_,Term)|T],Acc,Res) :- !,
724		reverse_and_project_on_action_term(T,[Term|Acc],Res).
725		reverse_and_project_on_action_term([H|T],Acc,Res) :-
726		add_error(reverse_and_project_on_action_term,'Illegal action: ',H),
727		reverse_and_project_on_action_term(T,[H|Acc],Res).
728
729		project_on_action_term([],[]).
730		project_on_action_term([action(_,Term)|T],Res) :- !, Res=[Term|TR],
731		project_on_action_term(T,TR).
732		project_on_action_term([H|T],Res) :-
733		add_error(project_on_action_term,'Illegal action: ',H),
734		project_on_action_term(T,Res).
735
736		extract_trace_from_transition_ids([],_CurrentState,_,Trace,Trace).
737		extract_trace_from_transition_ids([TransId|Rest],CurrentState,Limit,AccTrace,Trace) :-
738		compute_op_string(TransId,CurrentState,Limit,OpTerm,OpString,DestState),!,
739		extract_trace_from_transition_ids(Rest,DestState,Limit,
740		[action(OpString,OpTerm)|AccTrace],Trace).
741		extract_trace_from_transition_ids([TransId|_],CurrentState,_,_,_Trace) :-
742		add_error(state_space,'Could not execute transition id: ', TransId:from(CurrentState)),fail.
743
744		:- use_module(translate,[translate_event_with_src_and_target_id/5]).
745		compute_op_string(jump(TO),_CurID,_,Term,String,DestID) :- !, Term=jump,String=jump,DestID=TO.
746		compute_op_string(TransId,CurID,Limit,Term,String,DestID) :- transition(CurID,Term,TransId,DestID),
747		translate_event_with_src_and_target_id(Term,CurID,DestID,Limit,String).
748
749		% reset history and forward history, but not state-space itself
750		state_space_reset :-
751		reset_trace,
752		retractall(history(_)),
753		retractall(forward_history(_)),
754		retractall(current_state_id(_)),
755		retractall(current_options(_)),
756		assertz(history([])),
757		assertz(current_state_id(root)).
758
759		reset_not_interesting :- retractall(not_interesting(_)), reset_counter(not_interesting_nodes).
760
761		mark_as_not_interesting(ID) :- assertz(not_interesting(ID)), inc_counter(not_interesting_nodes).
762
763		set_current_state_id(ID) :- (retract(current_state_id(_)) -> true ; true),
764		assertz(current_state_id(ID)).
765
766		state_space_clean_all :-
767		retractall(state_space_version_in_file(_)),
768		retractall_visited_expression(_),
769		reset_open_ids,
770		retractall(not_invariant_checked(_)),
771		reset_not_interesting,
772		retractall(max_reached_for_node(_)),
773		retractall(time_out_for_node(_,_,_)),
774		retractall(time_out_for_invariant(_)),
775		retractall(time_out_for_assertions(_)),
776		retractall(use_no_timeout(_)),
777		retractall(state_error(_,_,_)),
778		clear_context_state,
779		reset_transition_store,
780		retractall(operation_not_yet_covered(_)),
781		retractall(hash_to_id(_,_)),
782		retractall(id_back_edge(_,_,_)),
783		retractall(hash_to_nauty_id(_,_)),
784		retractall(id_to_marker(_,_)),
785		retractall(specialized_inv(_,_)),
786		%retractall(reuse_operation(_,_,_,_)),
787		retractall(history(_)),
788		retractall(forward_history(_)),
789		retractall(op_trace_ids(_)),
790		retractall(current_state_id(_)),
791		retractall(current_options(_)).
792
793		% this is only used from within the Tcl/Tk animator at the moment:
794		delete_node(ID) :- print(deleting(ID)),nl,
795		retractall_visited_expression(ID),
796		retractall_invariant_violated(ID),
797		retract_open_node_and_update_processed_nodes(ID),
798		retractall(not_invariant_checked(ID)),
799		(retract(not_interesting(ID)) -> inc_counter_by(not_interesting_nodes,-1) ; true),
800		retractall(max_reached_for_node(ID)),
801		retractall(time_out_for_node(ID,_,_)),
802		retractall(time_out_for_invariant(ID)),
803		retractall(time_out_for_assertions(ID)),
804		retractall(use_no_timeout(ID)),
805		retractall(state_error(ID,_,_)),
806		retractall(transition(ID,_,_,_)),
807		% to do: check if operation_not_yet_covered(_) changes
808		retract_hash(ID),
809		retractall(id_to_marker(ID,_)).
810
811		retract_hash(ID) :- retract(hash_to_id(Hash,ID)), retractall(hash_to_nauty_id(_TermHash,Hash)),fail.
812		retract_hash(_).
813
814		assert_max_reached_for_node(Id) :- %print_message(max_reached_for_node(Id)),
815		(max_reached_for_node(Id) -> true ; assertz(max_reached_for_node(Id))).
816
817		:- use_module(probsrc(debug),[debug_mode/1]).
818		assert_time_out_for_node(Id,OpName,TypeOfTimeOut) :-
819		(debug_mode(off),functor(TypeOfTimeOut,virtual_time_out,_) -> true % can easily happen when parameters are unbounded
820		; print_message(time_out_for_node(Id,OpName,TypeOfTimeOut))),
821		(time_out_for_node(Id,OpName,_) -> true ; assertz(time_out_for_node(Id,OpName,TypeOfTimeOut))).
822		assert_time_out_for_invariant(Id) :- print_message(time_out_for_invariant(Id)),
823		(time_out_for_invariant(Id) -> true ; assertz(time_out_for_invariant(Id))).
824		assert_time_out_for_assertions(Id) :- print_message(time_out_for_assertions(Id)),
825		(time_out_for_assertions(Id) -> true ; assertz(time_out_for_assertions(Id))).
826
827		max_reached_or_timeout_for_node(Id) :-
828		(max_reached_for_node(Id) ; time_out_for_node(Id,_,_)).
829		/* ---------------------- */
830		/* state space saving */
831		/* ---------------------- */
832
833		:- dynamic state_space_version_in_file/1. %
834		state_space_version(1).
835
836		check_state_space_version :- state_space_version(V),
837		(state_space_version_in_file(F) -> true ; F=0),
838		(V>F -> add_message(state_space,'Warning: saved state_space may be incompatible with current version: ',F:V) ; true).
839
840		% save all infos of state space (transitions, evaluated invariants, ...)
841		tcltk_save_state_space(File) :-
842		print('% saving full state space to: '), print(File),nl,
843		open(File,write,Stream,[encoding(utf8)]),
844		print_state_space(Stream),
845		close(Stream),
846		print_message(done).
847
848
849		:- use_module(tools_printing, [print_dynamic_fact/2,print_dynamic_pred/4]).
850		print_state_space(Stream) :-
851		state_space_version(V),
852		print_dynamic_fact(Stream,state_space_version_in_file(V)),
853		% TO DO: maybe also save some important preferences, and warn user and/or propose to adapt preferences ?
854		print_dynamic_pred(Stream,state_space,history,1),
855		print_dynamic_pred(Stream,state_space,forward_history,1),
856		print_dynamic_pred(Stream,state_space,op_trace_ids,1),
857		print_dynamic_pred(Stream,state_space,current_state_id,1),
858		print_dynamic_pred(Stream,state_space,current_options,1),
859		print_dynamic_pred(Stream,state_space,packed_visited_expression,2),
860		print_dynamic_pred(Stream,state_space,not_invariant_checked,1),
861		print_dynamic_pred(Stream,state_space,not_interesting,1),
862		print_dynamic_pred(Stream,state_space,max_reached_for_node,1),
863		print_dynamic_pred(Stream,state_space,time_out_for_node,3),
864		print_dynamic_pred(Stream,state_space,use_no_timeout,1),
865		print_dynamic_pred(Stream,state_space,transition,4),
866		print_dynamic_pred(Stream,state_space,transition_info,2),
867		print_dynamic_pred(Stream,state_space,operation_not_yet_covered,1),
868		print_dynamic_pred(Stream,state_space,state_error,3),
869		print_state_space_open_nodes(Stream),
870		print_stored_values(Stream),
871		get_counter(states,X),
872		write_term(Stream,saved_gennum_count(X),[quoted(true)]),write(Stream,'.'),nl(Stream).
873
874		saved_gennum_count(99999).
875
876		/* ---------------------- */
877		/* state space loading */
878		/* ---------------------- */
879
880		tcltk_load_state(File) :- state_space_clean_all,
881		print('Loading: '), print(File),nl,
882		user_consult_without_redefine_warning(File), % this will read in bind_skeleton/2, ..., next_value_id/1
883		check_state_space_version,
884		print('Generating open node info'),nl,
885		transfer_open_node_info,
886		print('Transfer state packing info'),nl,
887		transfer_state_packing_info,
888		print('Recomputing hash index'),nl,
889		recompute_all_hash,
890		(saved_gennum_count(X) -> reset_state_counter(X) ; true),
891		reset_processed_nodes_counter, % TO DO: restore or save it
892		reset_next_state_error_id_counter, % DITTO
893		print('Done'),nl,!.
894		tcltk_load_state(File) :-
895		add_error(tcltk_load_state,'Could not load state from file: ',File),
896		state_space_initialise.
897
898		:- dynamic not_all_z_saved/1, not_all_transitions_added_saved/1.
899		:- dynamic bind_skeleton/2, stored_value/2, stored_value_hash_to_id/2, next_value_id/1.
900
901		% transfer facts read into state_space into other modules:
902		transfer_open_node_info :- retract(not_all_z_saved(X)), %print(not_all_z(X)),nl,
903		assert_not_all_z(X),fail.
904		transfer_open_node_info :- retract(not_all_transitions_added_saved(X)),
905		assert_not_all_transitions_added(X),fail.
906		transfer_open_node_info.
907		% now for transferring to state_packing module info generated by print_stored_values
908		transfer_state_packing_info :- retract(bind_skeleton(X,Y)), %print(skel(X)),nl,
909		assertz(state_packing:bind_skeleton(X,Y)),fail.
910		transfer_state_packing_info :- retract(stored_value(X,Y)),
911		assertz(state_packing:stored_value(X,Y)),fail.
912		transfer_state_packing_info :- retract(stored_value_hash_to_id(X,Y)),
913		assertz(state_packing:stored_value_hash_to_id(X,Y)),fail.
914		transfer_state_packing_info :- retract(next_value_id(X)),
915		state_packing:set_next_value_id(X),fail.
916		transfer_state_packing_info.
917
918		recompute_all_hash :-
919		retractall(hash_to_id(_,_)),retractall(id_to_marker(_,_)),
920		retractall(hash_to_nauty_id(_,_)),
921		visited_expression(ID,StateTemplate),
922		state_space_exploration_modes:compute_hash(StateTemplate,Hash,Marker),
923		assertz(hash_to_id(Hash,ID)),
924		assertz(id_to_marker(ID,Marker)),
925		fail.
926		recompute_all_hash.
927
928		:- use_module(hashing,[my_term_hash/2]).
929		% generates a hash for the entire state space not depending on the order in which states where added
930		compute_full_state_space_hash(Hash) :-
931		%listing(hash_to_id/2), listing(packed_visited_expression/2),
932		findall(Hash,hash_to_id(Hash,_),ListOfHashCodes),
933		sort(ListOfHashCodes,SortedList),
934		my_term_hash(SortedList,Hash).
935		% TO DO: also provide transition hashes
936
937		:- use_module(tools_meta,[safe_on_exception/3]).
938		user_consult_without_redefine_warning(File) :-
939		get_set_optional_prolog_flag(redefine_warnings, Old, off),
940		get_set_optional_prolog_flag(single_var_warnings, Old2, off),
941		(safe_on_exception(Exc,
942		%consult(File), %
943		load_files([File], [load_type(source),compilation_mode(consult),encoding(utf8)]),
944		(nl,print('Exception occurred:'),print(Exc),nl,fail))
945		-> OK=true ; OK=false),
946		get_set_optional_prolog_flag(redefine_warnings, _, Old),
947		get_set_optional_prolog_flag(single_var_warnings, _, Old2),
948		OK=true.
949
950
951
952		execute_id_trace_from_current(ID,OpIDL,StateIDList) :-
953		current_state_id(CurID),
954		reverse([CurID|StateIDList],Rev),
955		Rev = [Dest|TRev], (Dest==ID -> true ; print(not_eq(Dest,ID)),nl),
956		retract(history(H)),
957		update_forward_history(OpIDL), % check if OpIDL conforms to forward history and keep it
958		append(TRev,H,NewH),
959		assertz(history(NewH)),
960		retract(op_trace_ids(OldTrace)),
961		reverse(OpIDL,NewTrace),
962		append(NewTrace,OldTrace,Trace),
963		assertz(op_trace_ids(Trace)),
964		retractall(current_state_id(_)),
965		assertz(current_state_id(ID)).
966		%execute_trace_to_node(OpL,StateIDList). /* <----- BOTTLENECK FOR LONG SEQUENCES */
967		%generate_trace([],Acc,Acc).
968		%generate_trace([OpTerm|T],Acc,Res) :-
969		% translate:translate_event(OpTerm,OpString),
970		% generate_trace(T,[action(OpString,OpTerm)|Acc],Res).
971
972		update_forward_history(TransitionIds) :-
973		(retract(forward_history(Forward)),
974		prune_forward_history(TransitionIds,Forward,NewForward)
975		-> assert(forward_history(NewForward))
976		; true).
977		% try and prune forward history if it matches operation trace
978		prune_forward_history([],ForwardHistory,ForwardHistory).
979		prune_forward_history([TransID|T],[forward(_,TransID)|TF],Res) :-
980		prune_forward_history(T,TF,Res).
981
982		try_set_trace_by_transition_ids(TransIds) :-
983		(set_trace_by_transition_ids(TransIds) -> true
984		; add_internal_error('Call failed:',set_trace_by_transition_ids(TransIds))).
985
986		set_trace_by_transition_ids(TransitionIds) :-
987		extract_history_from_transition_ids(TransitionIds,root,[],[],Last,History,OpTrace),
988		%visited_expression(Last,LastState,LastCond),
989		retractall(history(_)),
990		retractall(forward_history(_)), % TODO: we could try and recover a new forward history if transition ids match current history^forward history
991		update_forward_history(TransitionIds),
992		retractall(current_state_id(_)),
993		retractall(op_trace_ids(_)),
994		assertz(history(History)),
995		assertz(op_trace_ids(OpTrace)),
996		assertz(current_state_id(Last)).
997
998
999		extract_history_from_transition_ids([],CurrentState,History,Trace,CurrentState,History,Trace).
1000		extract_history_from_transition_ids([TransId|Rest],CurrentState,AccHist,AccTrace,Last,History,Trace) :-
1001		transition(CurrentState,_,TransId,DestState),!,
1002		extract_history_from_transition_ids(Rest,DestState,[CurrentState|AccHist],
1003		[TransId|AccTrace],Last,History,Trace).
1004		extract_history_from_transition_ids([skip|Rest],CurrentState,AccHist,AccTrace,Last,History,Trace) :- !,
1005		extract_history_from_transition_ids(Rest,CurrentState,AccHist,AccTrace,Last,History,Trace).
1006		extract_history_from_transition_ids([TransId|_],CurrentState,_,_,_,_,_Trace) :-
1007		add_error(state_space,'Could not execute transition id: ', TransId:from(CurrentState)),fail.
1008
1009		% extend trace from current state
1010		extend_trace_by_transition_ids(TransitionIds) :-
1011		current_state_id(CurID),
1012		history(OldH), op_trace_ids(OldOT),
1013		extract_history_from_transition_ids(TransitionIds,CurID,OldH,OldOT,Last,History,OpTrace),
1014		retractall(history(_)), retractall(forward_history(_)),
1015		retractall(current_state_id(_)),
1016		retractall(op_trace_ids(_)),
1017		assertz(history(History)),
1018		assertz(op_trace_ids(OpTrace)),
1019		assertz(current_state_id(Last)).
1020
1021		/* --------------------------------- */
1022		:- dynamic max_nr_of_new_nodes/1.
1023
1024		% negative number or non-number signifies no limit
1025		set_max_nr_of_new_impl_trans_nodes(MaxNrOfNewNodes) :-
1026		retractall(max_nr_of_new_nodes(_)),
1027		(number(MaxNrOfNewNodes), MaxNrOfNewNodes>=0
1028		-> assertz(max_nr_of_new_nodes(MaxNrOfNewNodes))
1029		; true). % no need to store limit; we will explore as much as needed
1030
1031		get_max_nr_of_new_impl_trans_nodes(MaxNrOfNewNodes) :-
1032		(max_nr_of_new_nodes(Max) -> MaxNrOfNewNodes=Max; MaxNrOfNewNodes = 0).
1033
1034		% used e.g., in refinement or ltl checker
1035		impl_trans_term(From,ActionAsTerm,To) :-
1036		compute_transitions_if_necessary_saved(From),
1037		transition(From,ActionAsTerm,_TID,To).
1038
1039		% a variation also giving the transition id:
1040		impl_trans_id(From,ActionAsTerm,TransitionID,To) :-
1041		compute_transitions_if_necessary_saved(From),
1042		transition(From,ActionAsTerm,TransitionID,To).
1043
1044		impl_trans_term_all(From,Ops) :-
1045		compute_transitions_if_necessary_saved(From),
1046		findall(op(Id,ActionAsTerm,To),
1047		transition(From,ActionAsTerm,Id,To),
1048		Ops).
1049
1050		% true if e.g., a time-out occurred during computation of all transitions
1051		impl_trans_not_complete(From) :- max_reached_or_timeout_for_node(From).
1052
1053		compute_transitions_if_necessary_saved(From) :-
1054		catch(
1055		compute_transitions_if_necessary(From),
1056		error(forced_interrupt_error('User has interrupted the current execution'),_),
1057		user_interrupts:process_interrupted_error_message).
1058
1059		:- use_module(tcltk_interface,[compute_all_transitions_if_necessary/2]).
1060		compute_transitions_if_necessary(From) :-
1061		not_all_transitions_added(From),!,
1062		decrease_max_nr_of_new_nodes(From),
1063		compute_all_transitions_if_necessary(From,false).
1064		compute_transitions_if_necessary(_From).
1065
1066		decrease_max_nr_of_new_nodes(ID) :-
1067		retract(max_nr_of_new_nodes(Max)),!,
1068		( Max>0 ->
1069		NewMax is Max-1,
1070		assertz(max_nr_of_new_nodes(NewMax))
1071		; Max=0 -> NM is -1,
1072		assertz(max_nr_of_new_nodes(NM)),
1073		add_warning(state_space,'Maximum number of new nodes reached for CTL/LTL/refinement check, node id = ',ID),
1074		fail
1075		; % negative number: re-assert and fail
1076		assertz(max_nr_of_new_nodes(Max)),
1077		fail).
1078		decrease_max_nr_of_new_nodes(_). % no limit stored; just proceed
1079
1080		% will be called from TCL/TK side
1081		max_nr_of_new_nodes_limit_not_reached :-
1082		max_nr_of_new_nodes(N),N>0.
1083
1084		:- use_module(specfile,[b_or_z_mode/0, csp_mode/0, csp_with_bz_mode/0]).
1085		retract_open_node(NodeID) :- retract_open_node_and_update_processed_nodes(NodeID),
1086		(b_or_z_mode -> assertz(not_invariant_checked(NodeID)) ; true).
1087
1088		reset_processed_nodes_counter :- reset_counter(processed_nodes).
1089		%reset_processed_nodes_counter(Nr) :- set_counter(processed_nodes,Nr).
1090
1091		retract_open_node_and_update_processed_nodes(NodeID) :-
1092		retract_open_node_direct(NodeID),
1093		inc_processed.
1094
1095		inc_processed :-
1096		inc_counter(processed_nodes).
1097
1098		pop_id_from_front(ID) :- pop_id_from_front_direct(ID), inc_processed.
1099		pop_id_from_end(ID) :- pop_id_from_end_direct(ID), inc_processed.
1100	?	pop_id_oldest(ID) :- pop_id_oldest_direct(ID), inc_processed.
1101
1102
1103
1104		/* --------------------------------- */
1105
1106		% find initialised states; very similar to is_initial_state_id/1
1107		% but is used by ltl/ctl/sap
1108		% TO DO: merge these two variations of the same concept
1109
1110		:- use_module(specfile,[animation_mode/1]).
1111
1112		find_initialised_states(Init) :-
1113		animation_mode(Mode),
1114		( init_states_mode_cst_init(Mode) ->
1115		findall(I,find_init1(root,I,_),Init)
1116		; init_states_mode_one_step(Mode) ->
1117		next_states_from_root(Init)
1118		;
1119		fail).
1120
1121		% find trace to some initialised state
1122		find_trace_to_initial_state(Target,Trace) :- animation_mode(Mode),
1123		find_aux(Mode,Target,Trace).
1124		find_aux(Mode,Target,[root,Target]) :-
1125		init_states_mode_one_step(Mode).
1126		find_aux(Mode,Target,[root|Trace]) :-
1127		init_states_mode_cst_init(Mode),
1128		find_init1(root,Target,Trace).
1129
1130
1131		init_states_mode_cst_init(b).
1132		init_states_mode_cst_init(z).
1133		init_states_mode_cst_init(csp_and_b).
1134
1135		init_states_mode_one_step(csp).
1136		init_states_mode_one_step(cspm).
1137		init_states_mode_one_step(xtl).
1138		%init_states_mode_one_step(promela).
1139
1140		next_states_from_root(States) :-
1141		impl_trans_term_all(root,Ops),
1142		findall(S, member(op(_Id,_,S),Ops), States).
1143
1144		find_init1(Start,Init,Trace) :- Start==Init,!,Trace=[]. % usually called with Start=Init=root
1145		find_init1(Start,Init,[State|Rest]) :-
1146		impl_trans_term(Start,O,State),
1147		find_init2(O,State,Init,Rest).
1148		find_init2(O,Init,Init,[]) :-
1149		has_functor_and_maybe_tau(O,'$initialise_machine').
1150		find_init2(O,State,Init,Path) :-
1151		has_functor_and_maybe_tau(O,'$setup_constants'),
1152		find_init1(State,Init,Path).
1153		find_init2(start_cspm_MAIN,State,Init,Path) :-
1154		find_init1(State,Init,Path).
1155		find_init2(start_cspm(_Proc),State,Init,Path) :-
1156		find_init1(State,Init,Path).
1157
1158		% has_functor_and_maybe_tau(Term,Functor)
1159		% checks if Term has the form "Functor(...)" or "tau(Functor(...))"
1160		% this is used for CSP||B specification where the initialisation is wrapped with
1161		% in a tau operator
1162		has_functor_and_maybe_tau(tau(Term),Functor) :-
1163		has_functor_and_maybe_tau(Term,Functor),!.
1164		has_functor_and_maybe_tau(Term,Functor) :-
1165		functor(Term,Functor,_).
1166
1167		% compute how far the state is from the root node using back_edge markers (if available)
1168		try_compute_depth_of_state_id(root,R) :- !, R=0.
1169		try_compute_depth_of_state_id(Node,Depth) :- id_back_edge(Node,Depth,_Back).
1170
1171		% optional registering of back_edges: to quickly find trace from root and to computed depth/diameter
1172		register_back_edge(ID,FromID) :-
1173		try_compute_depth_of_state_id(FromID,D),!,
1174		D1 is D+1,
1175		assertz(id_back_edge(ID,D1,FromID)).
1176		register_back_edge(ID,FromID) :- write(cannot_store_back_edge(ID,FromID)),nl.
1177
1178		/* --------------------------------- */
1179
1180		%
1181		% Code to compute equivalence classes
1182		% using the standard DFA minimization algorithm
1183
1184		:- dynamic equivalent/2.
1185		% state_space:compute_equivalence_classes
1186		:- public compute_equivalence_classes/0.
1187
1188		compute_equivalence_classes :- init_equi,
1189		split_equivalence_classes,nl,
1190		print_equi.
1191
1192		print_equi :- state_space:equivalent(A,B), visited_expression(A,State),
1193		visited_expression(B,StateB),
1194		nl,
1195		print(A), print(' : '), print(State),nl,
1196		print(B), print(' : '), print(StateB),nl,fail.
1197		print_equi.
1198
1199		init_equi :- retractall(equivalent(_,_)),
1200		packed_visited_expression(ID,_State),
1201		\+ not_all_transitions_added(ID),
1202		findall(Action,transition(ID,Action,_,_),List),
1203		packed_visited_expression(ID2,_S2), ID2 @> ID,
1204		\+ not_all_transitions_added(ID2),
1205		findall(Action,transition(ID2,Action,_,_),List),
1206		assertz(equivalent(ID,ID2)), % they have the same signature
1207		%print(equivalent(ID,ID2)),nl,
1208		fail.
1209		init_equi :- print(finished_initialising),nl.
1210
1211		split_equivalence_classes :- retractall(echange),
1212		equivalent(ID1,ID2),
1213		transition(ID1,A,_,Dest1),
1214		transition(ID2,A,_,Dest2),
1215		\+ check_equi(Dest1,Dest2),
1216		retract(equivalent(ID1,ID2)), % splitting class
1217		% print(diff(ID1,ID2, A, Dest1, Dest2)),nl,
1218		assert_echange,
1219		fail.
1220		split_equivalence_classes :- echange -> split_equivalence_classes ; true.
1221
1222		:- dynamic echange/0.
1223		assert_echange :- echange -> true ; assertz(echange),print('.'),flush_output.
1224
1225		check_equi(A,B) :- A=B -> true ; A @<B -> equivalent(A,B) ; equivalent(B,A).
1226
1227		/*
1228		% benchmark how much time it takes to copy the state space state_space:bench_state_space.
1229		bench_state_space :-
1230		statistics(walltime,_),
1231		(state_space:packed_visited_expression(ID,S), assertz(pve(ID,S)),fail ; true),
1232		statistics(walltime,[_,Delta]), format('Time to copy packed_visited_expression: ~w ms~n',[Delta]),
1233		(state_space:transition(A,B,C,D), assertz(tr(A,B,C,D)),fail ; true),
1234		statistics(walltime,[_,Delta2]), format('Time to copy transition: ~w ms~n',[Delta2]),
1235		(state_packing:stored_value(A,B), assertz(sv(A,B)),fail ; true),
1236		(state_packing:stored_value_hash_to_id(A,B), assertz(svhi(A,B)),fail ; true),
1237		statistics(walltime,[_,Delta3]), format('Time to copy stored_value: ~w ms~n',[Delta3]).
1238		*/
1239
1240		:- public portray_state_space/0.
1241		portray_state_space :- packed_visited_expression(ID,S), functor(S,F,N),
1242		format('State ~w : ~w/~w~n',[ID,F,N]), fail.
1243		portray_state_space :- transition(ID,Action,TransID,DestID),
1244		format(' ~w: ~w -- ~w --> ~w~n',[TransID,ID,Action,DestID]),fail.
1245		portray_state_space.
1246
1247		bench_state_space :- statistics(walltime,[W1,_]),
1248		(packed_visited_expression(_,_), fail ; true),
1249		statistics(walltime,[W2,_]), T1 is W2-W1,
1250		format('Time to inspect all states: ~w ms walltime~n',[T1]),
1251		(visited_expression(_,_), fail ; true),
1252		statistics(walltime,[W3,_]), T2 is W3-W2,
1253		format('Time to inspect and unpack all states: ~w ms walltime~n',[T2]),
1254		(transition(_,_,_,_), fail ; true),
1255		statistics(walltime,[W4,_]), T3 is W4-W3,
1256		format('Time to inspect all transitions: ~w ms walltime~n',[T3]),
1257		(visited_expression(_,E), my_term_hash(E,_), fail ; true),
1258		statistics(walltime,[W5,_]), T4 is W5-W4,
1259		format('Time to inspect, unpack and hash all states: ~w ms walltime~n',[T4]).
1260
1261		% ----------------------------
1262		% COUNTER EXAMPLE MANAGEMENT
1263
1264		% store counter example nodes and transition ids; used by LTL model checking for example
1265
1266
1267		:- dynamic counterexample_node/1.
1268		:- dynamic counterexample_op/1.
1269
1270		add_counterexample_node(NodeID) :- assertz(counterexample_node(NodeID)).
1271		add_counterexample_op(TransID) :-
1272		(counterexample_op(TransID) -> true ; assertz(counterexample_op(TransID))).
1273
1274
1275		reset_counterexample :-
1276		retractall(counterexample_node(_)),
1277		retractall(counterexample_op(_)).
1278
1279		:- register_event_listener(play_counterexample,reset_counterexample,
1280		'Reset marked nodes from previous counterexamples.').
1281
1282		set_counterexample_by_transition_ids(TransIds) :-
1283		set_trace_by_transition_ids(TransIds),
1284		maplist(add_counterexample_op,TransIds),
1285		extract_history_from_transition_ids(TransIds,root,[],[],_Last,History,_OpTrace),
1286		maplist(add_counterexample_node,History).