Examples with Node soot.jimple.spark.pag.Node used on opensource projects

Example 1 with Node

use of soot.jimple.spark.pag.Node in project soot by Sable.

the class GeomPointsTo method finalizeInternalData.

/**
 * 1. Update the call graph;
 * 2. Eliminate the pointers, objects, and constraints related to the unreachable code.
 */
private void finalizeInternalData() {
    // Compute the set of reachable functions after the points-to analysis
    markReachableMethods();
    // Clean the unreachable objects
    for (Iterator<IVarAbstraction> it = allocations.iterator(); it.hasNext(); ) {
        IVarAbstraction po = it.next();
        AllocNode obj = (AllocNode) po.getWrappedNode();
        SootMethod sm = obj.getMethod();
        if (sm != null && func2int.containsKey(sm) == false)
            it.remove();
    }
    // Clean the unreachable pointers
    final Vector<AllocNode> removeSet = new Vector<AllocNode>();
    for (Iterator<IVarAbstraction> it = pointers.iterator(); it.hasNext(); ) {
        IVarAbstraction pn = it.next();
        // Is this pointer obsoleted?
        Node vn = pn.getWrappedNode();
        SootMethod sm = null;
        if (vn instanceof LocalVarNode) {
            sm = ((LocalVarNode) vn).getMethod();
        } else if (vn instanceof AllocDotField) {
            sm = ((AllocDotField) vn).getBase().getMethod();
        }
        if (sm != null) {
            if (func2int.containsKey(sm) == false) {
                pn.deleteAll();
                vn.discardP2Set();
                it.remove();
                continue;
            }
        }
        if (pn.getRepresentative() != pn)
            continue;
        removeSet.clear();
        if (pn.hasPTResult()) {
            // We remove the useless shapes or objects
            Set<AllocNode> objSet = pn.get_all_points_to_objects();
            for (Iterator<AllocNode> oit = objSet.iterator(); oit.hasNext(); ) {
                AllocNode obj = oit.next();
                IVarAbstraction po = consG.get(obj);
                if (!po.reachable() || pn.isDeadObject(obj)) {
                    removeSet.add(obj);
                }
            }
            for (AllocNode obj : removeSet) pn.remove_points_to(obj);
            pn.drop_duplicates();
        } else {
            // We also remove unreachable objects for SPARK nodes
            PointsToSetInternal pts = vn.getP2Set();
            pts.forall(new P2SetVisitor() {

                @Override
                public void visit(Node n) {
                    IVarAbstraction pan = findInternalNode(n);
                    // The removeSet is misused as a contains set
                    if (pan.reachable())
                        removeSet.add((AllocNode) n);
                }
            });
            pts = vn.makeP2Set();
            for (AllocNode an : removeSet) pts.add(an);
        }
    }
    // Clean the useless constraints
    for (Iterator<PlainConstraint> cIt = constraints.iterator(); cIt.hasNext(); ) {
        PlainConstraint cons = cIt.next();
        IVarAbstraction lhs = cons.getLHS();
        IVarAbstraction rhs = cons.getRHS();
        if (!lhs.reachable() || !rhs.reachable() || getMethodIDFromPtr(lhs) == Constants.UNKNOWN_FUNCTION || getMethodIDFromPtr(rhs) == Constants.UNKNOWN_FUNCTION) {
            cIt.remove();
        }
    }
    // We reassign the IDs to the pointers, objects and constraints
    pointers.reassign();
    allocations.reassign();
    constraints.reassign();
}

Example 2 with Node

use of soot.jimple.spark.pag.Node in project soot by Sable.

the class GeomPointsTo method field_p2set.

// --------------------------------------------------------------------------------------------------------
// -------------------------------Soot Standard Points-to Query Interface----------------------------------
// --------------------------------------------------------------------------------------------------------
private PointsToSetInternal field_p2set(PointsToSet s, final SparkField f) {
    if (!(s instanceof PointsToSetInternal))
        throw new RuntimeException("Base pointers must be stored in *PointsToSetInternal*.");
    PointsToSetInternal bases = (PointsToSetInternal) s;
    final PointsToSetInternal ret = getSetFactory().newSet(f.getType(), this);
    bases.forall(new P2SetVisitor() {

        public final void visit(Node n) {
            Node nDotF = ((AllocNode) n).dot(f);
            if (nDotF != null) {
                // nDotF.getP2Set() has been discarded in solve()
                IVarAbstraction pn = consG.get(nDotF);
                if (pn == null || hasTransformed || nDotF.getP2Set() != EmptyPointsToSet.v()) {
                    ret.addAll(nDotF.getP2Set(), null);
                    return;
                }
                pn = pn.getRepresentative();
                // PointsToSetInternal ptSet = nDotF.makeP2Set();
                for (AllocNode obj : pn.get_all_points_to_objects()) {
                    ret.add(obj);
                // ptSet.add(obj);
                }
            }
        }
    });
    return ret;
}

Example 3 with Node

use of soot.jimple.spark.pag.Node in project soot by Sable.

the class GeomPointsTo method finalizeSootData.

/**
 * Update the reachable methods and SPARK points-to results.
 */
private void finalizeSootData() {
    // We remove the unreachable functions from Soot internal structures
    Scene.v().releaseReachableMethods();
    // The we rebuild it from the updated Soot call graph
    Scene.v().getReachableMethods();
    if (!opts.geom_trans()) {
        // At querying time, the SPARK points-to container acts as a query cache
        for (IVarAbstraction pn : pointers) {
            // Keep only the points-to results for representatives
            if (pn != pn.getRepresentative()) {
                continue;
            }
            // Simplify
            if (pn.hasPTResult()) {
                pn.keepPointsToOnly();
                Node vn = pn.getWrappedNode();
                vn.discardP2Set();
            }
        }
    } else {
        // Do we need to obtain the context insensitive points-to result?
        transformToCIResult();
    }
}

Example 4 with Node

use of soot.jimple.spark.pag.Node in project soot by Sable.

the class GeomPointsTo method mergeLocalVariables.

/**
 * As pointed out by the single entry graph contraction, temporary variables incur high redundancy in points-to relations.
 * Find and eliminate the redundancies as early as possible.
 *
 * Methodology:
 * If q has unique incoming edge p -> q, p and q are both local to the same function, and they have the same type, we merge them.
 */
private void mergeLocalVariables() {
    IVarAbstraction my_lhs, my_rhs;
    Node lhs, rhs;
    int[] count = new int[pointers.size()];
    // We count how many ways a local pointer can be assigned
    for (PlainConstraint cons : constraints) {
        my_lhs = cons.getLHS();
        my_rhs = cons.getRHS();
        switch(cons.type) {
            case Constants.NEW_CONS:
            case Constants.ASSIGN_CONS:
                count[my_rhs.id]++;
                break;
            case Constants.LOAD_CONS:
                lhs = my_lhs.getWrappedNode();
                count[my_rhs.id] += lhs.getP2Set().size();
                break;
        }
    }
    // Second time scan, we delete those constraints that only duplicate points-to information
    for (Iterator<PlainConstraint> cons_it = constraints.iterator(); cons_it.hasNext(); ) {
        PlainConstraint cons = cons_it.next();
        if (cons.type == Constants.ASSIGN_CONS) {
            my_lhs = cons.getLHS();
            my_rhs = cons.getRHS();
            lhs = my_lhs.getWrappedNode();
            rhs = my_rhs.getWrappedNode();
            if ((lhs instanceof LocalVarNode) && (rhs instanceof LocalVarNode)) {
                SootMethod sm1 = ((LocalVarNode) lhs).getMethod();
                SootMethod sm2 = ((LocalVarNode) rhs).getMethod();
                if (sm1 == sm2 && count[my_rhs.id] == 1 && lhs.getType() == rhs.getType()) {
                    // They are local to the same function and the receiver pointer has unique incoming edge
                    // More importantly, they have the same type.
                    my_rhs.merge(my_lhs);
                    cons_it.remove();
                }
            }
        }
    }
    // Third scan, update the constraints with the representatives
    for (PlainConstraint cons : constraints) {
        my_lhs = cons.getLHS();
        my_rhs = cons.getRHS();
        switch(cons.type) {
            case Constants.NEW_CONS:
                cons.setRHS(my_rhs.getRepresentative());
                break;
            case Constants.ASSIGN_CONS:
            case Constants.LOAD_CONS:
            case Constants.STORE_CONS:
                cons.setLHS(my_lhs.getRepresentative());
                cons.setRHS(my_rhs.getRepresentative());
                break;
        }
    }
}

Example 5 with Node

use of soot.jimple.spark.pag.Node in project soot by Sable.

the class GeomPointsTo method preprocess.

/**
 *	Read in the program facts generated by SPARK.
 *  We also construct our own call graph and pointer variables.
 */
private void preprocess() {
    int id;
    int s, t;
    // Build the call graph
    n_func = Scene.v().getReachableMethods().size() + 1;
    call_graph = new CgEdge[n_func];
    n_calls = 0;
    n_reach_spark_user_methods = 0;
    id = 1;
    QueueReader<MethodOrMethodContext> smList = Scene.v().getReachableMethods().listener();
    CallGraph soot_callgraph = Scene.v().getCallGraph();
    while (smList.hasNext()) {
        final SootMethod func = smList.next().method();
        func2int.put(func, id);
        int2func.put(id, func);
        /*
			 * We cannot identify all entry methods since some entry methods call themselves.
			 * In that case, the Soot CallGraph.isEntryMethod() function returns false.
			 */
        if (soot_callgraph.isEntryMethod(func) || func.isEntryMethod()) {
            CgEdge p = new CgEdge(Constants.SUPER_MAIN, id, null, call_graph[Constants.SUPER_MAIN]);
            call_graph[Constants.SUPER_MAIN] = p;
            n_calls++;
        }
        if (!func.isJavaLibraryMethod())
            ++n_reach_spark_user_methods;
        id++;
    }
    // Next, we scan all the call edges and rebuild the call graph in our own vocabulary
    QueueReader<Edge> edgeList = Scene.v().getCallGraph().listener();
    while (edgeList.hasNext()) {
        Edge edge = edgeList.next();
        if (edge.isClinit()) {
            continue;
        }
        SootMethod src_func = edge.src();
        SootMethod tgt_func = edge.tgt();
        s = func2int.get(src_func);
        t = func2int.get(tgt_func);
        // Create a new call edge in our own format
        CgEdge p = new CgEdge(s, t, edge, call_graph[s]);
        call_graph[s] = p;
        edgeMapping.put(edge, p);
        // We collect callsite information
        Stmt callsite = edge.srcStmt();
        if (edge.isThreadRunCall() || edge.kind().isExecutor() || edge.kind().isAsyncTask()) {
            // We don't modify the treatment to the thread run() calls
            thread_run_callsites.add(callsite);
        } else if (edge.isInstance() && !edge.isSpecial()) {
            // We try to refine the virtual callsites (virtual + interface) with multiple call targets
            InstanceInvokeExpr expr = (InstanceInvokeExpr) callsite.getInvokeExpr();
            if (expr.getMethodRef().getSignature().contains("<java.lang.Thread: void start()>")) {
                // It is a thread start function
                thread_run_callsites.add(callsite);
            } else {
                p.base_var = findLocalVarNode(expr.getBase());
                if (SootInfo.countCallEdgesForCallsite(callsite, true) > 1 && p.base_var != null) {
                    multiCallsites.add(callsite);
                }
            }
        }
        ++n_calls;
    }
    // We build the wrappers for all the pointers built by SPARK
    for (Iterator<VarNode> it = getVarNodeNumberer().iterator(); it.hasNext(); ) {
        VarNode vn = it.next();
        IVarAbstraction pn = makeInternalNode(vn);
        pointers.add(pn);
    }
    for (Iterator<AllocDotField> it = getAllocDotFieldNodeNumberer().iterator(); it.hasNext(); ) {
        AllocDotField adf = it.next();
        // Some allocdotfield is invalid, we check and remove them
        SparkField field = adf.getField();
        if (field instanceof SootField) {
            // This is an instance field of a class
            Type decType = ((SootField) field).getDeclaringClass().getType();
            Type baseType = adf.getBase().getType();
            // baseType must be a sub type of decType
            if (!castNeverFails(baseType, decType))
                continue;
        }
        IVarAbstraction pn = makeInternalNode(adf);
        pointers.add(pn);
    }
    for (Iterator<AllocNode> it = getAllocNodeNumberer().iterator(); it.hasNext(); ) {
        AllocNode obj = it.next();
        IVarAbstraction pn = makeInternalNode(obj);
        allocations.add(pn);
    }
    // The address constraints, new obj -> p
    for (Object object : allocSources()) {
        IVarAbstraction obj = makeInternalNode((AllocNode) object);
        Node[] succs = allocLookup((AllocNode) object);
        for (Node element0 : succs) {
            PlainConstraint cons = new PlainConstraint();
            IVarAbstraction p = makeInternalNode(element0);
            cons.expr.setPair(obj, p);
            cons.type = Constants.NEW_CONS;
            constraints.add(cons);
        }
    }
    // The assign constraints, p -> q
    Pair<Node, Node> intercall = new Pair<Node, Node>();
    for (Object object : simpleSources()) {
        IVarAbstraction p = makeInternalNode((VarNode) object);
        Node[] succs = simpleLookup((VarNode) object);
        for (Node element0 : succs) {
            PlainConstraint cons = new PlainConstraint();
            IVarAbstraction q = makeInternalNode(element0);
            cons.expr.setPair(p, q);
            cons.type = Constants.ASSIGN_CONS;
            intercall.setPair((VarNode) object, element0);
            cons.interCallEdges = lookupEdgesForAssignment(intercall);
            constraints.add(cons);
        }
    }
    intercall = null;
    assign2edges.clear();
    // The load constraints, p.f -> q
    for (Object object : loadSources()) {
        FieldRefNode frn = (FieldRefNode) object;
        IVarAbstraction p = makeInternalNode(frn.getBase());
        Node[] succs = loadLookup(frn);
        for (Node element0 : succs) {
            PlainConstraint cons = new PlainConstraint();
            IVarAbstraction q = makeInternalNode(element0);
            cons.f = frn.getField();
            cons.expr.setPair(p, q);
            cons.type = Constants.LOAD_CONS;
            constraints.add(cons);
        }
    }
    // The store constraints, p -> q.f
    for (Object object : storeSources()) {
        IVarAbstraction p = makeInternalNode((VarNode) object);
        Node[] succs = storeLookup((VarNode) object);
        for (Node element0 : succs) {
            PlainConstraint cons = new PlainConstraint();
            FieldRefNode frn = (FieldRefNode) element0;
            IVarAbstraction q = makeInternalNode(frn.getBase());
            cons.f = frn.getField();
            cons.expr.setPair(p, q);
            cons.type = Constants.STORE_CONS;
            constraints.add(cons);
        }
    }
    n_init_constraints = constraints.size();
    // Initialize other stuff
    low_cg = new int[n_func];
    vis_cg = new int[n_func];
    rep_cg = new int[n_func];
    indeg_cg = new int[n_func];
    scc_size = new int[n_func];
    block_num = new int[n_func];
    context_size = new long[n_func];
    max_context_size_block = new long[n_func];
}