+++ /dev/null
-/* Copyright (c) 2011-2022. The SimGrid Team. All rights reserved. */
-
-/* This program is free software; you can redistribute it and/or modify it
- * under the terms of the license (GNU LGPL) which comes with this package. */
-
-#include "src/mc/explo/LivenessChecker.hpp"
-#include "src/mc/Session.hpp"
-#include "src/mc/mc_config.hpp"
-#include "src/mc/mc_exit.hpp"
-#include "src/mc/mc_private.hpp"
-
-#include <boost/range/algorithm.hpp>
-#include <cstring>
-
-XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_liveness, mc, "Logging specific to algorithms for liveness properties verification");
-
-using api = simgrid::mc::Api;
-
-/********* Static functions *********/
-
-namespace simgrid {
-namespace mc {
-
-VisitedPair::VisitedPair(int pair_num, xbt_automaton_state_t automaton_state,
- std::shared_ptr<const std::vector<int>> atomic_propositions,
- std::shared_ptr<State> graph_state)
- : num(pair_num), automaton_state(automaton_state)
-{
- this->graph_state = std::move(graph_state);
- if (this->graph_state->system_state_ == nullptr)
- this->graph_state->system_state_ = std::make_shared<Snapshot>(pair_num);
- this->heap_bytes_used = api::get().get_remote_heap_bytes();
- this->actors_count = api::get().get_actors().size();
- this->other_num = -1;
- this->atomic_propositions = std::move(atomic_propositions);
-}
-
-static bool evaluate_label(const xbt_automaton_exp_label* l, std::vector<int> const& values)
-{
- switch (l->type) {
- case xbt_automaton_exp_label::AUT_OR:
- return evaluate_label(l->u.or_and.left_exp, values) || evaluate_label(l->u.or_and.right_exp, values);
- case xbt_automaton_exp_label::AUT_AND:
- return evaluate_label(l->u.or_and.left_exp, values) && evaluate_label(l->u.or_and.right_exp, values);
- case xbt_automaton_exp_label::AUT_NOT:
- return not evaluate_label(l->u.exp_not, values);
- case xbt_automaton_exp_label::AUT_PREDICAT:
- return values.at(api::get().compare_automaton_exp_label(l)) != 0;
- case xbt_automaton_exp_label::AUT_ONE:
- return true;
- default:
- xbt_die("Unexpected value for automaton");
- }
-}
-
-Pair::Pair(unsigned long expanded_pairs) : num(expanded_pairs) {}
-
-std::shared_ptr<const std::vector<int>> LivenessChecker::get_proposition_values() const
-{
- auto values = api::get().automaton_propositional_symbol_evaluate();
- return std::make_shared<const std::vector<int>>(std::move(values));
-}
-
-std::shared_ptr<VisitedPair> LivenessChecker::insert_acceptance_pair(simgrid::mc::Pair* pair)
-{
- auto new_pair =
- std::make_shared<VisitedPair>(pair->num, pair->automaton_state, pair->atomic_propositions, pair->graph_state);
-
- auto res = boost::range::equal_range(acceptance_pairs_, new_pair.get(), api::get().compare_pair());
-
- if (pair->search_cycle)
- for (auto i = res.first; i != res.second; ++i) {
- std::shared_ptr<simgrid::mc::VisitedPair> const& pair_test = *i;
- if (xbt_automaton_state_compare(pair_test->automaton_state, new_pair->automaton_state) != 0 ||
- *(pair_test->atomic_propositions) != *(new_pair->atomic_propositions) ||
- not api::get().snapshot_equal(pair_test->graph_state->system_state_.get(),
- new_pair->graph_state->system_state_.get()))
- continue;
- XBT_INFO("Pair %d already reached (equal to pair %d) !", new_pair->num, pair_test->num);
- exploration_stack_.pop_back();
- if (dot_output != nullptr)
- fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previous_pair_, pair_test->num,
- this->previous_request_.c_str());
- return nullptr;
- }
-
- acceptance_pairs_.insert(res.first, new_pair);
- return new_pair;
-}
-
-void LivenessChecker::remove_acceptance_pair(int pair_num)
-{
- for (auto i = acceptance_pairs_.begin(); i != acceptance_pairs_.end(); ++i)
- if ((*i)->num == pair_num) {
- acceptance_pairs_.erase(i);
- break;
- }
-}
-
-void LivenessChecker::replay()
-{
- XBT_DEBUG("**** Begin Replay ****");
-
- /* Intermediate backtracking */
- if (_sg_mc_checkpoint > 0) {
- const Pair* pair = exploration_stack_.back().get();
- if (pair->graph_state->system_state_) {
- api::get().restore_state(pair->graph_state->system_state_);
- return;
- }
- }
-
- get_session().restore_initial_state();
-
- /* Traverse the stack from the initial state and re-execute the transitions */
- int depth = 1;
- for (std::shared_ptr<Pair> const& pair : exploration_stack_) {
- if (pair == exploration_stack_.back())
- break;
-
- std::shared_ptr<State> state = pair->graph_state;
-
- if (pair->exploration_started) {
- state->get_transition()->replay();
- XBT_DEBUG("Replay (depth = %d) : %s (%p)", depth, state->get_transition()->to_string().c_str(), state.get());
- }
-
- /* Update statistics */
- visited_pairs_count_++;
- depth++;
- }
- XBT_DEBUG("**** End Replay ****");
-}
-
-/**
- * @brief Checks whether a given pair has already been visited by the algorithm.
- */
-int LivenessChecker::insert_visited_pair(std::shared_ptr<VisitedPair> visited_pair, simgrid::mc::Pair* pair)
-{
- if (_sg_mc_max_visited_states == 0)
- return -1;
-
- if (visited_pair == nullptr)
- visited_pair =
- std::make_shared<VisitedPair>(pair->num, pair->automaton_state, pair->atomic_propositions, pair->graph_state);
-
- auto range = boost::range::equal_range(visited_pairs_, visited_pair.get(), api::get().compare_pair());
-
- for (auto i = range.first; i != range.second; ++i) {
- const VisitedPair* pair_test = i->get();
- if (xbt_automaton_state_compare(pair_test->automaton_state, visited_pair->automaton_state) != 0 ||
- *(pair_test->atomic_propositions) != *(visited_pair->atomic_propositions) ||
- not api::get().snapshot_equal(pair_test->graph_state->system_state_.get(),
- visited_pair->graph_state->system_state_.get()))
- continue;
- if (pair_test->other_num == -1)
- visited_pair->other_num = pair_test->num;
- else
- visited_pair->other_num = pair_test->other_num;
- if (dot_output == nullptr)
- XBT_DEBUG("Pair %d already visited ! (equal to pair %d)", visited_pair->num, pair_test->num);
- else
- XBT_DEBUG("Pair %d already visited ! (equal to pair %d (pair %d in dot_output))", visited_pair->num,
- pair_test->num, visited_pair->other_num);
- (*i) = std::move(visited_pair);
- return (*i)->other_num;
- }
-
- visited_pairs_.insert(range.first, std::move(visited_pair));
- this->purge_visited_pairs();
- return -1;
-}
-
-void LivenessChecker::purge_visited_pairs()
-{
- if (_sg_mc_max_visited_states != 0 && visited_pairs_.size() > (std::size_t)_sg_mc_max_visited_states) {
- // Remove the oldest entry with a linear search:
- visited_pairs_.erase(
- boost::min_element(visited_pairs_, [](std::shared_ptr<VisitedPair> const a,
- std::shared_ptr<VisitedPair> const& b) { return a->num < b->num; }));
- }
-}
-
-LivenessChecker::LivenessChecker(Session* session) : Exploration(session) {}
-
-RecordTrace LivenessChecker::get_record_trace() // override
-{
- RecordTrace res;
- for (std::shared_ptr<Pair> const& pair : exploration_stack_)
- res.push_back(pair->graph_state->get_transition());
- return res;
-}
-
-void LivenessChecker::log_state() // override
-{
- XBT_INFO("Expanded pairs = %lu", expanded_pairs_count_);
- XBT_INFO("Visited pairs = %lu", visited_pairs_count_);
- XBT_INFO("Executed transitions = %lu", Transition::get_executed_transitions());
-}
-
-void LivenessChecker::show_acceptance_cycle(std::size_t depth)
-{
- XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
- XBT_INFO("| ACCEPTANCE CYCLE |");
- XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
- XBT_INFO("Counter-example that violates formula:");
- for (auto const& s : this->get_textual_trace())
- XBT_INFO(" %s", s.c_str());
- XBT_INFO("Path = %s", get_record_trace().to_string().c_str());
- log_state();
- XBT_INFO("Counter-example depth: %zu", depth);
-}
-
-std::vector<std::string> LivenessChecker::get_textual_trace() // override
-{
- std::vector<std::string> trace;
- for (std::shared_ptr<Pair> const& pair : exploration_stack_)
- trace.push_back(pair->graph_state->get_transition()->to_string());
-
- return trace;
-}
-
-std::shared_ptr<Pair> LivenessChecker::create_pair(const Pair* current_pair, xbt_automaton_state_t state,
- std::shared_ptr<const std::vector<int>> propositions)
-{
- ++expanded_pairs_count_;
- auto next_pair = std::make_shared<Pair>(expanded_pairs_count_);
- next_pair->automaton_state = state;
- next_pair->graph_state = std::make_shared<State>();
- next_pair->atomic_propositions = std::move(propositions);
- if (current_pair)
- next_pair->depth = current_pair->depth + 1;
- else
- next_pair->depth = 1;
- /* Add all enabled actors to the interleave set of the initial state */
- for (auto& act : api::get().get_actors()) {
- auto actor = act.copy.get_buffer();
- if (get_session().actor_is_enabled(actor->get_pid()))
- next_pair->graph_state->mark_todo(actor->get_pid());
- }
-
- next_pair->requests = next_pair->graph_state->count_todo();
- /* FIXME : get search_cycle value for each accepting state */
- if (next_pair->automaton_state->type == 1 || (current_pair && current_pair->search_cycle))
- next_pair->search_cycle = true;
- else
- next_pair->search_cycle = false;
- return next_pair;
-}
-
-void LivenessChecker::backtrack()
-{
- /* Traverse the stack backwards until a pair with a non empty interleave
- set is found, deleting all the pairs that have it empty in the way. */
- while (not exploration_stack_.empty()) {
- std::shared_ptr<simgrid::mc::Pair> current_pair = exploration_stack_.back();
- exploration_stack_.pop_back();
- if (current_pair->requests > 0) {
- /* We found a backtracking point */
- XBT_DEBUG("Backtracking to depth %d", current_pair->depth);
- exploration_stack_.push_back(std::move(current_pair));
- this->replay();
- XBT_DEBUG("Backtracking done");
- break;
- } else {
- XBT_DEBUG("Delete pair %d at depth %d", current_pair->num, current_pair->depth);
- if (current_pair->automaton_state->type == 1)
- this->remove_acceptance_pair(current_pair->num);
- }
- }
-}
-
-void LivenessChecker::run()
-{
- XBT_INFO("Check the liveness property %s", _sg_mc_property_file.get().c_str());
- api::get().automaton_load(_sg_mc_property_file.get().c_str());
-
- XBT_DEBUG("Starting the liveness algorithm");
- get_session().take_initial_snapshot();
-
- /* Initialize */
- this->previous_pair_ = 0;
-
- std::shared_ptr<const std::vector<int>> propos = this->get_proposition_values();
-
- // For each initial state of the property automaton, push a
- // (application_state, automaton_state) pair to the exploration stack:
- auto automaton_stack = api::get().get_automaton_state();
- for (auto* automaton_state : automaton_stack) {
- if (automaton_state->type == -1)
- exploration_stack_.push_back(this->create_pair(nullptr, automaton_state, propos));
- }
-
- /* Actually run the double DFS search for counter-examples */
- while (not exploration_stack_.empty()) {
- std::shared_ptr<Pair> current_pair = exploration_stack_.back();
-
- /* Update current state in buchi automaton */
- api::get().set_property_automaton(current_pair->automaton_state);
-
- XBT_DEBUG(
- "********************* ( Depth = %d, search_cycle = %d, interleave size = %zu, pair_num = %d, requests = %d)",
- current_pair->depth, current_pair->search_cycle, current_pair->graph_state->count_todo(), current_pair->num,
- current_pair->requests);
-
- if (current_pair->requests == 0) {
- this->backtrack();
- continue;
- }
-
- std::shared_ptr<VisitedPair> reached_pair;
- if (current_pair->automaton_state->type == 1 && not current_pair->exploration_started) {
- reached_pair = this->insert_acceptance_pair(current_pair.get());
- if (reached_pair == nullptr) {
- this->show_acceptance_cycle(current_pair->depth);
- throw LivenessError();
- }
- }
-
- /* Pair already visited ? stop the exploration on the current path */
- if (not current_pair->exploration_started) {
- int visited_num = this->insert_visited_pair(reached_pair, current_pair.get());
- if (visited_num != -1) {
- if (dot_output != nullptr) {
- fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previous_pair_, visited_num,
- this->previous_request_.c_str());
- fflush(dot_output);
- }
- XBT_DEBUG("Pair already visited (equal to pair %d), exploration on the current path stopped.", visited_num);
- current_pair->requests = 0;
- this->backtrack();
- continue;
- }
- }
-
- current_pair->graph_state->execute_next(current_pair->graph_state->next_transition());
- XBT_DEBUG("Execute: %s", current_pair->graph_state->get_transition()->to_string().c_str());
-
- if (dot_output != nullptr) {
- if (this->previous_pair_ != 0 && this->previous_pair_ != current_pair->num) {
- fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previous_pair_, current_pair->num,
- this->previous_request_.c_str());
- this->previous_request_.clear();
- }
- this->previous_pair_ = current_pair->num;
- this->previous_request_ = current_pair->graph_state->get_transition()->dot_string();
- if (current_pair->search_cycle)
- fprintf(dot_output, "%d [shape=doublecircle];\n", current_pair->num);
- fflush(dot_output);
- }
-
- if (not current_pair->exploration_started)
- visited_pairs_count_++;
-
- current_pair->requests--;
- current_pair->exploration_started = true;
-
- /* Get values of atomic propositions (variables used in the property formula) */
- std::shared_ptr<const std::vector<int>> prop_values = this->get_proposition_values();
-
- // For each enabled transition in the property automaton, push a
- // (application_state, automaton_state) pair to the exploration stack:
- for (int i = xbt_dynar_length(current_pair->automaton_state->out) - 1; i >= 0; i--) {
- auto transition_succ_label = api::get().get_automaton_transition_label(current_pair->automaton_state->out, i);
- auto transition_succ_dst = api::get().get_automaton_transition_dst(current_pair->automaton_state->out, i);
- if (evaluate_label(transition_succ_label, *prop_values))
- exploration_stack_.push_back(this->create_pair(current_pair.get(), transition_succ_dst, prop_values));
- }
- }
-
- XBT_INFO("No property violation found.");
- log_state();
-}
-
-Exploration* create_liveness_checker(Session* session)
-{
- return new LivenessChecker(session);
-}
-
-} // namespace mc
-} // namespace simgrid
