+/* Copyright (c) 2008-2023. 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/odpor/ReversibleRaceCalculator.hpp"
+#include "src/mc/explo/odpor/Execution.hpp"
+#include "src/mc/transition/Transition.hpp"
+#include "src/mc/transition/TransitionSynchro.hpp"
+
+#include <functional>
+#include <unordered_map>
+#include <xbt/asserts.h>
+#include <xbt/ex.h>
+
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_odpor_reversible_race, mc_dfs, "ODPOR exploration algorithm of the model-checker");
+
+namespace simgrid::mc::odpor {
+
+/**
+ The reversible race detector should only be used if we already have the assumption
+ e1 <* e2 (see Source set: a foundation for ODPOR). In particular this means that :
+ - e1 -->_E e2
+ - proc(e1) != proc(e2)
+ - there is no event e3 s.t. e1 --> e3 --> e2
+*/
+
+bool ReversibleRaceCalculator::is_race_reversible(const Execution& E, Execution::EventHandle e1,
+ Execution::EventHandle e2)
+{
+ using Action = Transition::Type;
+ using Handler = std::function<bool(const Execution&, const Transition*, const Transition*)>;
+ using HandlerMap = std::unordered_map<Action, Handler>;
+
+ const static HandlerMap handlers = {
+ {Action::ACTOR_JOIN, &ReversibleRaceCalculator::is_race_reversible_ActorJoin},
+ {Action::BARRIER_ASYNC_LOCK, &ReversibleRaceCalculator::is_race_reversible_BarrierAsyncLock},
+ {Action::BARRIER_WAIT, &ReversibleRaceCalculator::is_race_reversible_BarrierWait},
+ {Action::COMM_ASYNC_SEND, &ReversibleRaceCalculator::is_race_reversible_CommSend},
+ {Action::COMM_ASYNC_RECV, &ReversibleRaceCalculator::is_race_reversible_CommRecv},
+ {Action::COMM_TEST, &ReversibleRaceCalculator::is_race_reversible_CommTest},
+ {Action::COMM_WAIT, &ReversibleRaceCalculator::is_race_reversible_CommWait},
+ {Action::MUTEX_ASYNC_LOCK, &ReversibleRaceCalculator::is_race_reversible_MutexAsyncLock},
+ {Action::MUTEX_TEST, &ReversibleRaceCalculator::is_race_reversible_MutexTest},
+ {Action::MUTEX_TRYLOCK, &ReversibleRaceCalculator::is_race_reversible_MutexTrylock},
+ {Action::MUTEX_UNLOCK, &ReversibleRaceCalculator::is_race_reversible_MutexUnlock},
+ {Action::MUTEX_WAIT, &ReversibleRaceCalculator::is_race_reversible_MutexWait},
+ {Action::OBJECT_ACCESS, &ReversibleRaceCalculator::is_race_reversible_ObjectAccess},
+ {Action::RANDOM, &ReversibleRaceCalculator::is_race_reversible_Random},
+ {Action::SEM_ASYNC_LOCK, &ReversibleRaceCalculator::is_race_reversible_SemAsyncLock},
+ {Action::SEM_UNLOCK, &ReversibleRaceCalculator::is_race_reversible_SemUnlock},
+ {Action::SEM_WAIT, &ReversibleRaceCalculator::is_race_reversible_SemWait},
+ {Action::TESTANY, &ReversibleRaceCalculator::is_race_reversible_TestAny},
+ {Action::WAITANY, &ReversibleRaceCalculator::is_race_reversible_WaitAny}};
+
+ const auto* other_transition = E.get_transition_for_handle(e1);
+ const auto* t2 = E.get_transition_for_handle(e2);
+ if (const auto handler = handlers.find(t2->type_); handler != handlers.end()) {
+ return handler->second(E, other_transition, t2);
+ } else {
+ xbt_die("There is currently no specialized computation for the transition "
+ "'%s' for computing reversible races in ODPOR, so the model checker cannot "
+ "determine how to proceed. Please submit a bug report requesting "
+ "that the transition be supported in SimGrid using ODPPR and consider "
+ "using the other model-checking algorithms supported by SimGrid instead "
+ "in the meantime",
+ t2->to_string().c_str());
+ }
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_ActorJoin(const Execution&, const Transition* /*other_transition*/,
+ const Transition* /*t2*/)
+{
+ // ActorJoin races with another event iff its target `T` is the same as
+ // the actor executing the other transition. Clearly, then, we could not join
+ // on that actor `T` and then run a transition by `T`, so no race is reversible
+ return false;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_BarrierAsyncLock(const Execution&,
+ const Transition* /*other_transition*/,
+ const Transition* /*t2*/)
+{
+ // BarrierAsyncLock is always enabled
+ return true;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_BarrierWait(const Execution& E, const Transition* other_transition,
+ const Transition* /*t2*/)
+{
+ // If the other event is a barrier lock event, then we
+ // are not reversible; otherwise we are reversible.
+ const auto other_action = other_transition->type_;
+ return other_action != Transition::Type::BARRIER_ASYNC_LOCK;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_CommRecv(const Execution&, const Transition* /*other_transition*/,
+ const Transition* /*t2*/)
+{
+ // CommRecv is always enabled
+ return true;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_CommSend(const Execution&, const Transition* /*other_transition*/,
+ const Transition* /*t2*/)
+{
+ // CommSend is always enabled
+ return true;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_CommWait(const Execution& E, const Transition* other_transition,
+ const Transition* /*t2*/)
+{
+ // If the other event is a communication event, then we
+ // are not reversible; otherwise we are reversible.
+ const auto other_action = other_transition->type_;
+ return other_action != Transition::Type::COMM_ASYNC_SEND && other_action != Transition::Type::COMM_ASYNC_RECV;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_CommTest(const Execution&, const Transition* /*other_transition*/,
+ const Transition* /*t2*/)
+{
+ // CommTest is always enabled
+ return true;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_MutexAsyncLock(const Execution&,
+ const Transition* /*other_transition*/,
+ const Transition* /*t2*/)
+{
+ // MutexAsyncLock is always enabled
+ return true;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_MutexTest(const Execution&, const Transition* /*other_transition*/,
+ const Transition* /*t2*/)
+{
+ // MutexTest is always enabled
+ return true;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_MutexTrylock(const Execution&, const Transition* /*other_transition*/,
+ const Transition* /*t2*/)
+{
+ // MutexTrylock is always enabled
+ return true;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_MutexUnlock(const Execution&, const Transition* /*other_transition*/,
+ const Transition* /*t2*/)
+{
+ // MutexUnlock is always enabled
+ return true;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_MutexWait(const Execution& E, const Transition* /*other_transition*/,
+ const Transition* /*t2*/)
+{
+ // TODO: for now we over approximate the reversibility
+
+ return true;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_SemAsyncLock(const Execution&, const Transition* /*other_transition*/,
+ const Transition* /*t2*/)
+{
+ // SemAsyncLock is always enabled
+ return true;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_SemUnlock(const Execution&, const Transition* /*other_transition*/,
+ const Transition* /*t2*/)
+{
+ // SemUnlock is always enabled
+ return true;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_SemWait(const Execution& E, const Transition* other_transition,
+ const Transition* /*t2*/)
+{
+
+ if (other_transition->type_ == Transition::Type::SEM_UNLOCK &&
+ static_cast<const SemaphoreTransition*>(other_transition)->get_capacity() <= 1) {
+ return false;
+ }
+ xbt_die("SEM_WAIT that is dependent with a SEM_UNLOCK should not be reversible. FixMe");
+ return true;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_ObjectAccess(const Execution&, const Transition* /*other_transition*/,
+ const Transition* /*t2*/)
+{
+ // Object access is always enabled
+ return true;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_Random(const Execution&, const Transition* /*other_transition*/,
+ const Transition* /*t2*/)
+{
+ // Random is always enabled
+ return true;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_TestAny(const Execution&, const Transition* /*other_transition*/,
+ const Transition* /*t2*/)
+{
+ // TestAny is always enabled
+ return true;
+}
+
+bool ReversibleRaceCalculator::is_race_reversible_WaitAny(const Execution&, const Transition* /*other_transition*/,
+ const Transition* /*t2*/)
+{
+ // TODO: We need to check if any of the transitions
+ // waited on occurred before `e1`
+ return true; // Let's overapproximate to not miss branches
+}
+
+} // namespace simgrid::mc::odpor
