#include "src/mc/explo/UdporChecker.hpp"
#include "src/mc/api/State.hpp"
+#include "src/mc/explo/udpor/Comb.hpp"
+#include "src/mc/explo/udpor/History.hpp"
+#include "src/mc/explo/udpor/maximal_subsets_iterator.hpp"
+
#include <xbt/asserts.h>
#include <xbt/log.h>
namespace simgrid::mc::udpor {
-UdporChecker::UdporChecker(const std::vector<char*>& args) : Exploration(args)
+UdporChecker::UdporChecker(const std::vector<char*>& args) : Exploration(args, true)
{
- /* Create initial data structures, if any ...*/
-
- // TODO: Initialize state structures for the search
+ // Initialize the map
}
void UdporChecker::run()
unfolding.insert(std::move(root_event));
C_root.add_event(root_event_handle);
- explore(std::move(C_root), EventSet(), EventSet(), std::move(initial_state), EventSet());
+ explore(C_root, EventSet(), EventSet(), std::move(initial_state), EventSet());
XBT_INFO("UDPOR exploration terminated -- model checking completed");
}
-void UdporChecker::explore(Configuration C, EventSet D, EventSet A, std::unique_ptr<State> stateC, EventSet prev_exC)
+void UdporChecker::explore(const Configuration& C, EventSet D, EventSet A, std::unique_ptr<State> stateC,
+ EventSet prev_exC)
{
- // Perform the incremental computation of exC
- //
- // TODO: This method will have side effects on
- // the unfolding, but the naming of the method
- // suggests it is doesn't have side effects. We should
- // reconcile this in the future
- auto [exC, enC] = compute_extension(C, prev_exC);
+ auto exC = compute_exC(C, *stateC, prev_exC);
+ const auto enC = compute_enC(C, exC);
// If enC is a subset of D, intuitively
// there aren't any enabled transitions
// "sleep-set blocked" trace.
if (enC.is_subset_of(D)) {
- if (C.get_events().size() > 0) {
-
- // g_var::nb_traces++;
-
- // TODO: Log here correctly
- // XBT_DEBUG("\n Exploring executions: %d : \n", g_var::nb_traces);
- // ...
- // ...
+ if (not C.get_events().empty()) {
+ // Report information...
}
// When `en(C)` is empty, intuitively this means that there
// are no enabled transitions that can be executed from the
// state reached by `C` (denoted `state(C)`), i.e. by some
// execution of the transitions in C obeying the causality
- // relation. Here, then, we would be in a deadlock.
+ // relation. Here, then, we may be in a deadlock (the other
+ // possibility is that we've finished running everything, and
+ // we wouldn't be in deadlock then)
if (enC.empty()) {
get_remote_app().check_deadlock();
}
// TODO: Add verbose logging about which event is being explored
- UnfoldingEvent* e = select_next_unfolding_event(A, enC);
+ const UnfoldingEvent* e = select_next_unfolding_event(A, enC);
xbt_assert(e != nullptr, "\n\n****** INVARIANT VIOLATION ******\n"
"UDPOR guarantees that an event will be chosen at each point in\n"
"the search, yet no events were actually chosen\n"
"*********************************\n\n");
- // Move the application into stateCe and actually make note of that state
+ // Move the application into stateCe and make note of that state
move_to_stateCe(*stateC, *e);
auto stateCe = record_current_state();
// D <-- D + {e}
D.insert(e);
- // TODO: Determine a value of K to use or don't use it at all
constexpr unsigned K = 10;
- auto J = compute_partial_alternative(D, C, K);
- if (!J.empty()) {
- J.subtract(C.get_events());
+ if (auto J = C.compute_k_partial_alternative_to(D, this->unfolding, K); J.has_value()) {
// Before searching the "right half", we need to make
// sure the program actually reflects the fact
restore_program_state_to(*stateC);
// Explore(C, D + {e}, J \ C)
- explore(C, D, std::move(J), std::move(stateC), std::move(prev_exC));
+ auto J_minus_C = J.value().get_events().subtracting(C.get_events());
+ explore(C, D, std::move(J_minus_C), std::move(stateC), std::move(prev_exC));
}
// D <-- D - {e}
clean_up_explore(e, C, D);
}
-std::tuple<EventSet, EventSet> UdporChecker::compute_extension(const Configuration& C, const EventSet& prev_exC) const
+EventSet UdporChecker::compute_exC(const Configuration& C, const State& stateC, const EventSet& prev_exC)
{
// See eqs. 5.7 of section 5.2 of [3]
// C = C' + {e_cur}, i.e. C' = C - {e_cur}
//
// Then
//
- // ex(C) = ex(C' + {e_cur}) = ex(C') / {e_cur} + U{<a, > : H }
- UnfoldingEvent* e_cur = C.get_latest_event();
- EventSet exC = prev_exC;
+ // ex(C) = ex(C' + {e_cur}) = ex(C') / {e_cur} +
+ // U{<a, K> : K is maximal, `a` depends on all of K, `a` enabled at config(K) }
+ const UnfoldingEvent* e_cur = C.get_latest_event();
+ EventSet exC = prev_exC;
exC.remove(e_cur);
- // ... fancy computations
+ for (const auto& [aid, actor_state] : stateC.get_actors_list()) {
+ for (const auto& transition : actor_state.get_enabled_transitions()) {
+ // First check for a specialized function that can compute the extension
+ // set "quickly" based on its type. Otherwise, fall back to computing
+ // the set "by hand"
+ const auto specialized_extension_function = incremental_extension_functions.find(transition->type_);
+ if (specialized_extension_function != incremental_extension_functions.end()) {
+ exC.form_union((specialized_extension_function->second)(C, transition));
+ } else {
+ exC.form_union(this->compute_exC_by_enumeration(C, transition));
+ }
+ }
+ }
+ return exC;
+}
+EventSet UdporChecker::compute_exC_by_enumeration(const Configuration& C, const std::shared_ptr<Transition> action)
+{
+ // Here we're computing the following:
+ //
+ // U{<a, K> : K is maximal, `a` depends on all of K, `a` enabled at config(K) }
+ //
+ // where `a` is the `action` given to us. Note that `a` is presumed to be enabled
+ EventSet incremental_exC;
+
+ for (auto begin =
+ maximal_subsets_iterator(C, {[&](const UnfoldingEvent* e) { return e->is_dependent_with(action.get()); }});
+ begin != maximal_subsets_iterator(); ++begin) {
+ const EventSet& maximal_subset = *begin;
+
+ // Determining if `a` is enabled here might not be possible while looking at `a` opaquely
+ // We leave the implementation as-is to ensure that any addition would be simple
+ // if it were ever added
+ const bool enabled_at_config_k = false;
+
+ if (enabled_at_config_k) {
+ auto candidate_handle = std::make_unique<UnfoldingEvent>(maximal_subset, action);
+ if (auto candidate_event = candidate_handle.get(); not unfolding.contains_event_equivalent_to(candidate_event)) {
+ // This is a new event (i.e. one we haven't yet seen)
+ unfolding.insert(std::move(candidate_handle));
+ incremental_exC.insert(candidate_event);
+ }
+ }
+ }
+ return incremental_exC;
+}
+
+EventSet UdporChecker::compute_enC(const Configuration& C, const EventSet& exC) const
+{
EventSet enC;
- return std::tuple<EventSet, EventSet>(exC, enC);
+ for (const auto e : exC) {
+ if (not e->conflicts_with(C)) {
+ enC.insert(e);
+ }
+ }
+ return enC;
}
void UdporChecker::move_to_stateCe(State& state, const UnfoldingEvent& e)
"one transition of the state of an visited event is enabled, yet no\n"
"state was actually enabled. Please report this as a bug.\n"
"*********************************\n\n");
- state.execute_next(next_actor);
+ state.execute_next(next_actor, get_remote_app());
}
void UdporChecker::restore_program_state_to(const State& stateC)
{
- // TODO: Perform state regeneration in the same manner as is done
- // in the DFSChecker.cpp
+ get_remote_app().restore_initial_state();
+ // TODO: We need to have the stack of past states available at this
+ // point. Since the method is recursive, we'll need to keep track of
+ // this as we progress
}
std::unique_ptr<State> UdporChecker::record_current_state()
auto next_state = this->get_current_state();
// In UDPOR, we care about all enabled transitions in a given state
- next_state->mark_all_enabled_todo();
+ next_state->consider_all();
return next_state;
}
-UnfoldingEvent* UdporChecker::select_next_unfolding_event(const EventSet& A, const EventSet& enC)
+const UnfoldingEvent* UdporChecker::select_next_unfolding_event(const EventSet& A, const EventSet& enC)
{
if (!enC.empty()) {
return *(enC.begin());
return nullptr;
}
-EventSet UdporChecker::compute_partial_alternative(const EventSet& D, const Configuration& C, const unsigned k) const
-{
- // TODO: Compute k-partial alternatives using [2]
- return EventSet();
-}
-
void UdporChecker::clean_up_explore(const UnfoldingEvent* e, const Configuration& C, const EventSet& D)
{
- // TODO: Perform clean up here
+ const EventSet C_union_D = C.get_events().make_union(D);
+ const EventSet es_immediate_conflicts = this->unfolding.get_immediate_conflicts_of(e);
+ const EventSet Q_CDU = C_union_D.make_union(es_immediate_conflicts.get_local_config());
+
+ // Move {e} \ Q_CDU from U to G
+ if (Q_CDU.contains(e)) {
+ this->unfolding.remove(e);
+ }
+
+ // foreach ê in #ⁱ_U(e)
+ for (const auto* e_hat : es_immediate_conflicts) {
+ // Move [ê] \ Q_CDU from U to G
+ const EventSet to_remove = e_hat->get_history().subtracting(Q_CDU);
+ this->unfolding.remove(to_remove);
+ }
}
RecordTrace UdporChecker::get_record_trace()
