Fixing more potential bugs for the reachability analysis.

[jpf-core.git] / src / main / gov / nasa / jpf / listener / DPORStateReducer.java

diff --git a/src/main/gov/nasa/jpf/listener/DPORStateReducer.java b/src/main/gov/nasa/jpf/listener/DPORStateReducer.java
index 0c513f21372d531a3d5b59754bb1de3445010380..104af2bd9993dd0cabb776e3e793e1a2060ba2fa 100644 (file)
--- a/src/main/gov/nasa/jpf/listener/DPORStateReducer.java
+++ b/src/main/gov/nasa/jpf/listener/DPORStateReducer.java
@@ -490,14 +490,14 @@ public class DPORStateReducer extends ListenerAdapter {
     // Update the state variables
     // Line 19 in the paper page 11 (see the heading note above)
     int stateId = search.getStateId();
-    currVisitedStates.add(stateId);
     // Insert state ID into the map if it is new
     if (!stateToEventMap.containsKey(stateId)) {
       HashSet<Integer> eventSet = new HashSet<>();
       stateToEventMap.put(stateId, eventSet);
     }
-    justVisitedStates.add(stateId);
     analyzeReachabilityAndCreateBacktrackPoints(search.getVM(), stateId);
+    justVisitedStates.add(stateId);
+    currVisitedStates.add(stateId);
   }
 
   // --- Functions related to Read/Write access analysis on shared fields
@@ -835,8 +835,14 @@ public class DPORStateReducer extends ListenerAdapter {
   // 2) We need to analyze and find conflicts for the reachable choices/events in the cycle
   // 3) Then we create a new backtrack point for every new conflict
   private void analyzeReachabilityAndCreateBacktrackPoints(VM vm, int stateId) {
-    // Perform this analysis only when there is a state match and state > 0 (state 0 is for boolean CG)
-    if (!vm.isNewState() && (stateId > 0)) {
+    // Perform this analysis only when:
+    // 1) there is a state match,
+    // 2) this is not during a switch to a new execution,
+    // 3) at least 2 choices/events have been explored (choiceCounter > 1),
+    // 4) the matched state has been encountered in the current execution, and
+    // 5) state > 0 (state 0 is for boolean CG)
+    if (!vm.isNewState() && !isEndOfExecution && choiceCounter > 1 &&
+            currVisitedStates.contains(stateId) && (stateId > 0)) {
       // Find the choice/event that marks the start of this cycle: first choice we explore for conflicts
       int conflictChoice = stateToChoiceCounterMap.get(stateId);
       int currentChoice = choiceCounter - 1;