1 /* Copyright (c) 2011-2022. The SimGrid Team. All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
6 #include "src/mc/checker/LivenessChecker.hpp"
7 #include "src/mc/Session.hpp"
8 #include "src/mc/mc_config.hpp"
9 #include "src/mc/mc_exit.hpp"
10 #include "src/mc/mc_private.hpp"
12 #include <boost/range/algorithm.hpp>
15 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_liveness, mc, "Logging specific to algorithms for liveness properties verification");
17 using api = simgrid::mc::Api;
19 /********* Static functions *********/
24 VisitedPair::VisitedPair(int pair_num, xbt_automaton_state_t automaton_state,
25 std::shared_ptr<const std::vector<int>> atomic_propositions,
26 std::shared_ptr<State> graph_state)
27 : num(pair_num), automaton_state(automaton_state)
29 this->graph_state = std::move(graph_state);
30 if (this->graph_state->system_state_ == nullptr)
31 this->graph_state->system_state_ = std::make_shared<Snapshot>(pair_num);
32 this->heap_bytes_used = api::get().get_remote_heap_bytes();
33 this->actors_count = api::get().get_actors_size();
35 this->atomic_propositions = std::move(atomic_propositions);
38 static bool evaluate_label(const xbt_automaton_exp_label* l, std::vector<int> const& values)
41 case xbt_automaton_exp_label::AUT_OR:
42 return evaluate_label(l->u.or_and.left_exp, values)
43 || evaluate_label(l->u.or_and.right_exp, values);
44 case xbt_automaton_exp_label::AUT_AND:
45 return evaluate_label(l->u.or_and.left_exp, values)
46 && evaluate_label(l->u.or_and.right_exp, values);
47 case xbt_automaton_exp_label::AUT_NOT:
48 return not evaluate_label(l->u.exp_not, values);
49 case xbt_automaton_exp_label::AUT_PREDICAT:
50 return values.at(api::get().compare_automaton_exp_label(l)) != 0;
51 case xbt_automaton_exp_label::AUT_ONE:
54 xbt_die("Unexpected value for automaton");
58 Pair::Pair(unsigned long expanded_pairs) : num(expanded_pairs)
61 std::shared_ptr<const std::vector<int>> LivenessChecker::get_proposition_values() const
63 auto values = api::get().automaton_propositional_symbol_evaluate();
64 return std::make_shared<const std::vector<int>>(std::move(values));
67 std::shared_ptr<VisitedPair> LivenessChecker::insert_acceptance_pair(simgrid::mc::Pair* pair)
70 std::make_shared<VisitedPair>(pair->num, pair->automaton_state, pair->atomic_propositions, pair->graph_state);
72 auto res = boost::range::equal_range(acceptance_pairs_, new_pair.get(), api::get().compare_pair());
74 if (pair->search_cycle) for (auto i = res.first; i != res.second; ++i) {
75 std::shared_ptr<simgrid::mc::VisitedPair> const& pair_test = *i;
76 if (api::get().automaton_state_compare(pair_test->automaton_state, new_pair->automaton_state) != 0 ||
77 *(pair_test->atomic_propositions) != *(new_pair->atomic_propositions) ||
78 not api::get().snapshot_equal(pair_test->graph_state->system_state_.get(), new_pair->graph_state->system_state_.get()))
80 XBT_INFO("Pair %d already reached (equal to pair %d) !", new_pair->num, pair_test->num);
81 exploration_stack_.pop_back();
82 if (dot_output != nullptr)
83 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previous_pair_, pair_test->num,
84 this->previous_request_.c_str());
88 acceptance_pairs_.insert(res.first, new_pair);
92 void LivenessChecker::remove_acceptance_pair(int pair_num)
94 for (auto i = acceptance_pairs_.begin(); i != acceptance_pairs_.end(); ++i)
95 if ((*i)->num == pair_num) {
96 acceptance_pairs_.erase(i);
101 void LivenessChecker::replay()
103 XBT_DEBUG("**** Begin Replay ****");
105 /* Intermediate backtracking */
106 if(_sg_mc_checkpoint > 0) {
107 const Pair* pair = exploration_stack_.back().get();
108 if (pair->graph_state->system_state_) {
109 api::get().restore_state(pair->graph_state->system_state_);
114 get_session().restore_initial_state();
116 /* Traverse the stack from the initial state and re-execute the transitions */
118 for (std::shared_ptr<Pair> const& pair : exploration_stack_) {
119 if (pair == exploration_stack_.back())
122 std::shared_ptr<State> state = pair->graph_state;
124 if (pair->exploration_started) {
125 state->get_transition()->replay();
126 XBT_DEBUG("Replay (depth = %d) : %s (%p)", depth, state->get_transition()->to_string().c_str(), state.get());
129 /* Update statistics */
130 visited_pairs_count_++;
133 XBT_DEBUG("**** End Replay ****");
137 * @brief Checks whether a given pair has already been visited by the algorithm.
139 int LivenessChecker::insert_visited_pair(std::shared_ptr<VisitedPair> visited_pair, simgrid::mc::Pair* pair)
141 if (_sg_mc_max_visited_states == 0)
144 if (visited_pair == nullptr)
146 std::make_shared<VisitedPair>(pair->num, pair->automaton_state, pair->atomic_propositions, pair->graph_state);
148 auto range = boost::range::equal_range(visited_pairs_, visited_pair.get(), api::get().compare_pair());
150 for (auto i = range.first; i != range.second; ++i) {
151 const VisitedPair* pair_test = i->get();
152 if (api::get().automaton_state_compare(pair_test->automaton_state, visited_pair->automaton_state) != 0 ||
153 *(pair_test->atomic_propositions) != *(visited_pair->atomic_propositions) ||
154 not api::get().snapshot_equal(pair_test->graph_state->system_state_.get(), visited_pair->graph_state->system_state_.get()))
156 if (pair_test->other_num == -1)
157 visited_pair->other_num = pair_test->num;
159 visited_pair->other_num = pair_test->other_num;
160 if (dot_output == nullptr)
161 XBT_DEBUG("Pair %d already visited ! (equal to pair %d)", visited_pair->num, pair_test->num);
163 XBT_DEBUG("Pair %d already visited ! (equal to pair %d (pair %d in dot_output))",
164 visited_pair->num, pair_test->num, visited_pair->other_num);
165 (*i) = std::move(visited_pair);
166 return (*i)->other_num;
169 visited_pairs_.insert(range.first, std::move(visited_pair));
170 this->purge_visited_pairs();
174 void LivenessChecker::purge_visited_pairs()
176 if (_sg_mc_max_visited_states != 0 && visited_pairs_.size() > (std::size_t)_sg_mc_max_visited_states) {
177 // Remove the oldest entry with a linear search:
178 visited_pairs_.erase(
179 boost::min_element(visited_pairs_, [](std::shared_ptr<VisitedPair> const a,
180 std::shared_ptr<VisitedPair> const& b) { return a->num < b->num; }));
184 LivenessChecker::LivenessChecker(Session* session) : Checker(session) {}
186 RecordTrace LivenessChecker::get_record_trace() // override
189 for (std::shared_ptr<Pair> const& pair : exploration_stack_)
190 res.push_back(pair->graph_state->get_transition());
194 void LivenessChecker::log_state() // override
196 XBT_INFO("Expanded pairs = %lu", expanded_pairs_count_);
197 XBT_INFO("Visited pairs = %lu", visited_pairs_count_);
198 XBT_INFO("Executed transitions = %lu", Transition::get_executed_transitions());
201 void LivenessChecker::show_acceptance_cycle(std::size_t depth)
203 XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
204 XBT_INFO("| ACCEPTANCE CYCLE |");
205 XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
206 XBT_INFO("Counter-example that violates formula:");
207 for (auto const& s : this->get_textual_trace())
208 XBT_INFO(" %s", s.c_str());
209 XBT_INFO("Path = %s", get_record_trace().to_string().c_str());
210 api::get().log_state();
211 XBT_INFO("Counter-example depth: %zu", depth);
214 std::vector<std::string> LivenessChecker::get_textual_trace() // override
216 std::vector<std::string> trace;
217 for (std::shared_ptr<Pair> const& pair : exploration_stack_)
218 trace.push_back(pair->graph_state->get_transition()->to_string());
223 std::shared_ptr<Pair> LivenessChecker::create_pair(const Pair* current_pair, xbt_automaton_state_t state,
224 std::shared_ptr<const std::vector<int>> propositions)
226 ++expanded_pairs_count_;
227 auto next_pair = std::make_shared<Pair>(expanded_pairs_count_);
228 next_pair->automaton_state = state;
229 next_pair->graph_state = std::make_shared<State>();
230 next_pair->atomic_propositions = std::move(propositions);
232 next_pair->depth = current_pair->depth + 1;
234 next_pair->depth = 1;
235 /* Add all enabled actors to the interleave set of the initial state */
236 for (auto& act : api::get().get_actors()) {
237 auto actor = act.copy.get_buffer();
238 if (get_session().actor_is_enabled(actor->get_pid()))
239 next_pair->graph_state->mark_todo(actor->get_pid());
242 next_pair->requests = next_pair->graph_state->count_todo();
243 /* FIXME : get search_cycle value for each accepting state */
244 if (next_pair->automaton_state->type == 1 || (current_pair && current_pair->search_cycle))
245 next_pair->search_cycle = true;
247 next_pair->search_cycle = false;
251 void LivenessChecker::backtrack()
253 /* Traverse the stack backwards until a pair with a non empty interleave
254 set is found, deleting all the pairs that have it empty in the way. */
255 while (not exploration_stack_.empty()) {
256 std::shared_ptr<simgrid::mc::Pair> current_pair = exploration_stack_.back();
257 exploration_stack_.pop_back();
258 if (current_pair->requests > 0) {
259 /* We found a backtracking point */
260 XBT_DEBUG("Backtracking to depth %d", current_pair->depth);
261 exploration_stack_.push_back(std::move(current_pair));
263 XBT_DEBUG("Backtracking done");
266 XBT_DEBUG("Delete pair %d at depth %d", current_pair->num, current_pair->depth);
267 if (current_pair->automaton_state->type == 1)
268 this->remove_acceptance_pair(current_pair->num);
273 void LivenessChecker::run()
275 XBT_INFO("Check the liveness property %s", _sg_mc_property_file.get().c_str());
276 api::get().automaton_load(_sg_mc_property_file.get().c_str());
278 XBT_DEBUG("Starting the liveness algorithm");
279 get_session().take_initial_snapshot();
282 this->previous_pair_ = 0;
284 std::shared_ptr<const std::vector<int>> propos = this->get_proposition_values();
286 // For each initial state of the property automaton, push a
287 // (application_state, automaton_state) pair to the exploration stack:
288 auto automaton_stack = api::get().get_automaton_state();
289 for (auto* automaton_state : automaton_stack) {
290 if (automaton_state->type == -1)
291 exploration_stack_.push_back(this->create_pair(nullptr, automaton_state, propos));
294 /* Actually run the double DFS search for counter-examples */
295 while (not exploration_stack_.empty()) {
296 std::shared_ptr<Pair> current_pair = exploration_stack_.back();
298 /* Update current state in buchi automaton */
299 api::get().set_property_automaton(current_pair->automaton_state);
302 "********************* ( Depth = %d, search_cycle = %d, interleave size = %zu, pair_num = %d, requests = %d)",
303 current_pair->depth, current_pair->search_cycle, current_pair->graph_state->count_todo(), current_pair->num,
304 current_pair->requests);
306 if (current_pair->requests == 0) {
311 std::shared_ptr<VisitedPair> reached_pair;
312 if (current_pair->automaton_state->type == 1 && not current_pair->exploration_started) {
313 reached_pair = this->insert_acceptance_pair(current_pair.get());
314 if (reached_pair == nullptr) {
315 this->show_acceptance_cycle(current_pair->depth);
316 throw LivenessError();
320 /* Pair already visited ? stop the exploration on the current path */
321 if (not current_pair->exploration_started) {
322 int visited_num = this->insert_visited_pair(reached_pair, current_pair.get());
323 if (visited_num != -1) {
324 if (dot_output != nullptr) {
325 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previous_pair_, visited_num,
326 this->previous_request_.c_str());
329 XBT_DEBUG("Pair already visited (equal to pair %d), exploration on the current path stopped.", visited_num);
330 current_pair->requests = 0;
336 current_pair->graph_state->execute_next(current_pair->graph_state->next_transition());
337 XBT_DEBUG("Execute: %s", current_pair->graph_state->get_transition()->to_string().c_str());
339 if (dot_output != nullptr) {
340 if (this->previous_pair_ != 0 && this->previous_pair_ != current_pair->num) {
341 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previous_pair_, current_pair->num,
342 this->previous_request_.c_str());
343 this->previous_request_.clear();
345 this->previous_pair_ = current_pair->num;
346 this->previous_request_ = api::get().request_get_dot_output(current_pair->graph_state->get_transition());
347 if (current_pair->search_cycle)
348 fprintf(dot_output, "%d [shape=doublecircle];\n", current_pair->num);
352 if (not current_pair->exploration_started)
353 visited_pairs_count_++;
355 current_pair->requests--;
356 current_pair->exploration_started = true;
358 /* Get values of atomic propositions (variables used in the property formula) */
359 std::shared_ptr<const std::vector<int>> prop_values = this->get_proposition_values();
361 // For each enabled transition in the property automaton, push a
362 // (application_state, automaton_state) pair to the exploration stack:
363 for (int i = api::get().get_dynar_length(current_pair->automaton_state->out) - 1; i >= 0; i--) {
364 auto transition_succ_label = api::get().get_automaton_transition_label(current_pair->automaton_state->out, i);
365 auto transition_succ_dst = api::get().get_automaton_transition_dst(current_pair->automaton_state->out, i);
366 if (evaluate_label(transition_succ_label, *prop_values))
367 exploration_stack_.push_back(this->create_pair(current_pair.get(), transition_succ_dst, prop_values));
371 XBT_INFO("No property violation found.");
372 api::get().log_state();
375 Checker* create_liveness_checker(Session* session)
377 return new LivenessChecker(session);
381 } // namespace simgrid