[Javapathfinder-devel] javapathfinder/src/gov/nasa/jpf/jvm ThreadInfo.java,1.8,1.9

[pcm <pcm...@us...>]

Update of /cvsroot/javapathfinder/javapathfinder/src/gov/nasa/jpf/jvm
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv15058/src/gov/nasa/jpf/jvm

Modified Files:
	ThreadInfo.java 
Log Message:
moved the idle loop detection out of the core and into gov.nasa.jpf.tools.IdleFilter listener, which
is also a bit more sophisticated. It checks not just for back jump threshold, but abandons the test if it
detects ArrayStoreInstructions or InvokeInstructions, assuming both are doing stuff that shouldn't be
ignored. The thing can be made vastly more sophisticated, but it nicely shows what can be done
with listeners. It passes the

  int[] a = new int[500]; // init loop  -> pass
  for (int i=0; i<a.length; i++) a[i] = i; 

   for (long l=0; l<1000000; l++); // bad idle loop  -> filter

test. To ease creation of listeners like this, I've also added a ListenerAdapter, which dummy implements
both VMListener and SearchListener, so that tools only have to override their relevant notificatiion
methods

Index: ThreadInfo.java
===================================================================
RCS file: /cvsroot/javapathfinder/javapathfinder/src/gov/nasa/jpf/jvm/ThreadInfo.java,v
retrieving revision 1.8
retrieving revision 1.9
diff -u -d -r1.8 -r1.9
--- ThreadInfo.java	7 May 2005 00:40:01 -0000	1.8
+++ ThreadInfo.java	10 May 2005 06:46:55 -0000	1.9
@@ -152,9 +152,6 @@
    */
   LinkedList lockedObjects = new LinkedList();
   
-  /** number of consecutive POR breaks this thread had since the last backtrack
-   */
-  int forcedPorBreaks;
   
   // the following parameters are configurable. Would be nice if we could keep
   // them on a per-instance basis, but there are a few locations
@@ -180,12 +177,7 @@
    * we don't treat access of the corresponding field as a boundary step 
    */
   static boolean porSyncDetection;
-  
-  /** after how many back jumps (potential loop closing GOTOs) do we get suspicious
-   * that we are in an endless loop that would never return from executePorStep
-   */
-  static int porMaxBackJumps;
-  
+    
   static boolean init (Config config) {
     threadDataPool = new HashPool();
     stackFramePool = new HashPool();
@@ -195,7 +187,6 @@
     porInEffect = config.getBoolean("vm.por");
     porFieldBoundaries = config.getBoolean("vm.por.field_boundaries");
     porSyncDetection = config.getBoolean("vm.por.sync_detection");
-    porMaxBackJumps = config.getInt("vm.por.max_backjumps", 50);
     
     return true;
   }
@@ -1222,8 +1213,6 @@
     hasChanged = new BitSet();
     lowestChanged = -1;
     
-    forcedPorBreaks = 0;
-    
     this.data = data;
   }
   
@@ -2088,8 +2077,6 @@
    */
   protected boolean executePorStep () throws JPFException {
         
-    int backJumps =0;
-    
     while (true) {      
       Instruction pc = executeInstruction();
             
@@ -2137,16 +2124,7 @@
       if ( yield || pc.isSchedulingRelevant(list.ks.ss, list.ks, this)) {
         yield = false;
         break;
-      }
-      
-      if (pc.isBackJump()) {
-        if (backJumps++ > porMaxBackJumps) {
-          if (forcedPorBreaks++ > 1) {
-            vm.setIgnoreState(true);
-          }
-          break; // we break before the jump backwards
-        }
-      }
+      }      
     }
     
     return true;