Add new entry in Release_Notes.

[simgrid.git] / src / mc / api / ActorState.hpp

diff --git a/src/mc/api/ActorState.hpp b/src/mc/api/ActorState.hpp
index 18be326..ed40454 100644 (file)
--- a/src/mc/api/ActorState.hpp
+++ b/src/mc/api/ActorState.hpp
@@ -9,6 +9,7 @@
 #include "src/kernel/activity/CommImpl.hpp"
 #include "src/mc/remote/RemotePtr.hpp"
 
+#include <algorithm>
 #include <exception>
 #include <vector>
 
@@ -97,8 +98,10 @@ public:
       mark_done();
     return times_considered_++;
   }
+  unsigned int get_max_considered() const { return max_consider_; }
   unsigned int get_times_considered() const { return times_considered_; }
   unsigned int get_times_not_considered() const { return max_consider_ - times_considered_; }
+  bool has_more_to_consider() const { return get_times_not_considered() > 0; }
   aid_t get_aid() const { return aid_; }
 
   /* returns whether the actor is marked as enabled in the application side */
@@ -115,7 +118,31 @@ public:
   }
   void mark_done() { this->state_ = InterleavingType::done; }
 
-  std::shared_ptr<Transition> get_transition() const { return get_transition(get_times_considered()); }
+  /**
+   * @brief Retrieves the transition that we should consider for execution by
+   * this actor from the State instance with respect to which this ActorState object
+   * is considered
+   */
+  std::shared_ptr<Transition> get_transition() const
+  {
+    // The rationale for this selection is as follows:
+    //
+    // 1. For transitions with only one possibility of execution,
+    // we always wish to select action `0` even if we've
+    // marked the transition already as considered (which
+    // we'll do if we explore a trace following that transition).
+    //
+    // 2. For transitions that can be considered multiple
+    // times, we want to be sure to select the most up-to-date
+    // action. In general, this means selecting that which is
+    // now being considered at this state. If, however, we've
+    // executed the
+    //
+    // The formula satisfies both of the above conditions:
+    //
+    // > std::clamp(times_considered_, 0u, max_consider_ - 1)
+    return get_transition(std::clamp(times_considered_, 0u, max_consider_ - 1));
+  }
 
   std::shared_ptr<Transition> get_transition(unsigned times_considered) const
   {
@@ -137,7 +164,8 @@ public:
 
   const std::vector<std::shared_ptr<Transition>>& get_enabled_transitions() const
   {
-    return this->pending_transitions_;
+    static const auto no_enabled_transitions = std::vector<std::shared_ptr<Transition>>();
+    return this->is_enabled() ? this->pending_transitions_ : no_enabled_transitions;
   };
 };