[Soot-list] PointsToAnalysis RuntimeError Aliasing

[Florian Strauß]

Hi everyone,

 

thanks for your help last time. 

 

I have an exception that I don’t understand. Maybe you have an idea:

I try to implement an aliasing analysis, which based on soot
pointsTo-Interfaces. 

Goal: All aliases of the local variable ‘variable’

Step 1 - Get all reachable objects:

p2Analysis = Scene.v().getPointsToAnalysis();

PointsToSet variablePointsTo = p2Analysis.reachingObjects(variable);

Step 2 – Unfortunately I don’t see a way to go backwards: From a referenced
object to the variable.* Hence, the next step is visiting all other
variables:

Step 2.1 – Compare ‘variable’ with all other local variables:

            for (Local local : allLocals) {

                  if(local != variable){

                        PointsToSet localPointsTo =
p2Analysis.reachingObjects(local);                     

 
if(localPointsTo.hasNonEmptyIntersection(variablePointsTo)){

                             aliases.add(local);

                        }

                  }

            }

Step 2.2 – Compare ‘variable’ with fields:

            for (SootField field : allFields) {

                  if(field.isStatic()){

                        PointsToSet staticFieldPointsTo =
p2Analysis.reachingObjects(field);

 
if(staticFieldPointsTo.hasNonEmptyIntersection(variablePointsTo)){

                             aliases.add(field);

                        }

                  }else{

                        for (Local local : allLocals) {

                             PointsToSet fieldPointsTo =
p2Analysis.reachingObjects(local, field); //raises RuntimeErrors

 
if(fieldPointsTo.hasNonEmptyIntersection(variablePointsTo)){

                                   aliases.add(field);

                             }

 

                        }

                  }

 

Step 2.1 works fine, but step 2.2 crashes and I do not see the reason. The
annotated line causes a runtime error:

Exception in thread "main" java.lang.RuntimeException: unnumbered:
<java.lang.String: int offset>

      at soot.util.ArrayNumberer.get(ArrayNumberer.java:51)

      at soot.util.JeddNumberer.get(JeddNumberer.java:35)

      at jedd.internal.Jedd.literal(Jedd.java:158)

      at
soot.jimple.paddle.BDDPointsToAnalysis.reachingObjects(BDDPointsToAnalysis.j
ava:103)

      at
soot.jimple.paddle.BDDPointsToAnalysis.reachingObjects(BDDPointsToAnalysis.j
ava:122)

 

*) Up to now, I use paddle. Maybe spark has the opportunity to go backwards
(at least internal?).

 

What am I doing wrong?

 

Best regards,

Florian

 

 

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