Examples with LocalCreation soot.jimple.toolkits.scalar.LocalCreation used on opensource projects

Example 1 with LocalCreation

use of soot.jimple.toolkits.scalar.LocalCreation in project soot by Sable.

the class Util method addExceptionAfterUnit.

/**
 * Insert a runtime exception before unit u of body b. Useful to analyze
 * broken code (which make reference to inexisting class for instance)
 * exceptionType: e.g., "java.lang.RuntimeException"
 */
public static void addExceptionAfterUnit(Body b, String exceptionType, Unit u, String m) {
    LocalCreation lc = new LocalCreation(b.getLocals());
    Local l = lc.newLocal(RefType.v(exceptionType));
    List<Unit> newUnits = new ArrayList<Unit>();
    Unit u1 = Jimple.v().newAssignStmt(l, Jimple.v().newNewExpr(RefType.v(exceptionType)));
    Unit u2 = Jimple.v().newInvokeStmt(Jimple.v().newSpecialInvokeExpr(l, Scene.v().makeMethodRef(Scene.v().getSootClass(exceptionType), "<init>", Collections.singletonList((Type) RefType.v("java.lang.String")), VoidType.v(), false), StringConstant.v(m)));
    Unit u3 = Jimple.v().newThrowStmt(l);
    newUnits.add(u1);
    newUnits.add(u2);
    newUnits.add(u3);
    b.getUnits().insertBefore(newUnits, u);
}

Example 2 with LocalCreation

use of soot.jimple.toolkits.scalar.LocalCreation in project soot by Sable.

the class BusyCodeMotion method internalTransform.

/**
 * performs the busy code motion.
 */
protected void internalTransform(Body b, String phaseName, Map<String, String> opts) {
    BCMOptions options = new BCMOptions(opts);
    HashMap<EquivalentValue, Local> expToHelper = new HashMap<EquivalentValue, Local>();
    Chain<Unit> unitChain = b.getUnits();
    if (Options.v().verbose())
        logger.debug("[" + b.getMethod().getName() + "]     performing Busy Code Motion...");
    CriticalEdgeRemover.v().transform(b, phaseName + ".cer");
    UnitGraph graph = new BriefUnitGraph(b);
    /* map each unit to its RHS. only take binary expressions */
    Map<Unit, EquivalentValue> unitToEquivRhs = new UnitMap<EquivalentValue>(b, graph.size() + 1, 0.7f) {

        protected EquivalentValue mapTo(Unit unit) {
            Value tmp = SootFilter.noInvokeRhs(unit);
            Value tmp2 = SootFilter.binop(tmp);
            if (tmp2 == null)
                tmp2 = SootFilter.concreteRef(tmp);
            return SootFilter.equiVal(tmp2);
        }
    };
    /* same as before, but without exception-throwing expressions */
    Map<Unit, EquivalentValue> unitToNoExceptionEquivRhs = new UnitMap<EquivalentValue>(b, graph.size() + 1, 0.7f) {

        protected EquivalentValue mapTo(Unit unit) {
            Value tmp = SootFilter.binopRhs(unit);
            tmp = SootFilter.noExceptionThrowing(tmp);
            return SootFilter.equiVal(tmp);
        }
    };
    /* if a more precise sideeffect-tester comes out, please change it here! */
    SideEffectTester sideEffect;
    if (Scene.v().hasCallGraph() && !options.naive_side_effect()) {
        sideEffect = new PASideEffectTester();
    } else {
        sideEffect = new NaiveSideEffectTester();
    }
    sideEffect.newMethod(b.getMethod());
    UpSafetyAnalysis upSafe = new UpSafetyAnalysis(graph, unitToEquivRhs, sideEffect);
    DownSafetyAnalysis downSafe = new DownSafetyAnalysis(graph, unitToNoExceptionEquivRhs, sideEffect);
    EarliestnessComputation earliest = new EarliestnessComputation(graph, upSafe, downSafe, sideEffect);
    LocalCreation localCreation = new LocalCreation(b.getLocals(), PREFIX);
    Iterator<Unit> unitIt = unitChain.snapshotIterator();
    {
        /* insert the computations at the earliest positions */
        while (unitIt.hasNext()) {
            Unit currentUnit = unitIt.next();
            for (EquivalentValue equiVal : earliest.getFlowBefore(currentUnit)) {
                // Value exp = equiVal.getValue();
                /* get the unic helper-name for this expression */
                Local helper = expToHelper.get(equiVal);
                // the beginning of the method
                if (currentUnit instanceof IdentityStmt)
                    currentUnit = getFirstNonIdentityStmt(b);
                if (helper == null) {
                    helper = localCreation.newLocal(equiVal.getType());
                    expToHelper.put(equiVal, helper);
                }
                /* insert a new Assignment-stmt before the currentUnit */
                Value insertValue = Jimple.cloneIfNecessary(equiVal.getValue());
                Unit firstComp = Jimple.v().newAssignStmt(helper, insertValue);
                unitChain.insertBefore(firstComp, currentUnit);
            }
        }
    }
    {
        /* replace old computations by the helper-vars */
        unitIt = unitChain.iterator();
        while (unitIt.hasNext()) {
            Unit currentUnit = unitIt.next();
            EquivalentValue rhs = unitToEquivRhs.get(currentUnit);
            if (rhs != null) {
                Local helper = expToHelper.get(rhs);
                if (helper != null)
                    ((AssignStmt) currentUnit).setRightOp(helper);
            }
        }
    }
    if (Options.v().verbose())
        logger.debug("[" + b.getMethod().getName() + "]     Busy Code Motion done!");
}

Example 3 with LocalCreation

use of soot.jimple.toolkits.scalar.LocalCreation in project soot by Sable.

the class DexNullArrayRefTransformer method internalTransform.

protected void internalTransform(final Body body, String phaseName, Map<String, String> options) {
    final ExceptionalUnitGraph g = new ExceptionalUnitGraph(body, DalvikThrowAnalysis.v());
    final LocalDefs defs = LocalDefs.Factory.newLocalDefs(g);
    final LocalCreation lc = new LocalCreation(body.getLocals(), "ex");
    boolean changed = false;
    for (Iterator<Unit> unitIt = body.getUnits().snapshotIterator(); unitIt.hasNext(); ) {
        Stmt s = (Stmt) unitIt.next();
        if (s.containsArrayRef()) {
            // Check array reference
            Value base = s.getArrayRef().getBase();
            if (isAlwaysNullBefore(s, (Local) base, defs)) {
                createThrowStmt(body, s, lc);
                changed = true;
            }
        } else if (s instanceof AssignStmt) {
            AssignStmt ass = (AssignStmt) s;
            Value rightOp = ass.getRightOp();
            if (rightOp instanceof LengthExpr) {
                // Check lengthof expression
                LengthExpr l = (LengthExpr) ass.getRightOp();
                Value base = l.getOp();
                if (base instanceof IntConstant) {
                    IntConstant ic = (IntConstant) base;
                    if (ic.value == 0) {
                        createThrowStmt(body, s, lc);
                        changed = true;
                    }
                } else if (base == NullConstant.v() || isAlwaysNullBefore(s, (Local) base, defs)) {
                    createThrowStmt(body, s, lc);
                    changed = true;
                }
            }
        }
    }
    if (changed)
        UnreachableCodeEliminator.v().transform(body);
}

Example 4 with LocalCreation

use of soot.jimple.toolkits.scalar.LocalCreation in project soot by Sable.

the class DexReturnValuePropagator method internalTransform.

@Override
protected void internalTransform(Body body, String phaseName, Map<String, String> options) {
    ExceptionalUnitGraph graph = new ExceptionalUnitGraph(body, DalvikThrowAnalysis.v(), true);
    LocalDefs localDefs = LocalDefs.Factory.newLocalDefs(graph);
    LocalUses localUses = null;
    LocalCreation localCreation = null;
    // a copy statement, we take the original operand
    for (Unit u : body.getUnits()) if (u instanceof ReturnStmt) {
        ReturnStmt retStmt = (ReturnStmt) u;
        if (retStmt.getOp() instanceof Local) {
            List<Unit> defs = localDefs.getDefsOfAt((Local) retStmt.getOp(), retStmt);
            if (defs.size() == 1 && defs.get(0) instanceof AssignStmt) {
                AssignStmt assign = (AssignStmt) defs.get(0);
                final Value rightOp = assign.getRightOp();
                final Value leftOp = assign.getLeftOp();
                // Copy over the left side if it is a local
                if (rightOp instanceof Local) {
                    // to return a;
                    if (!isRedefined((Local) rightOp, u, assign, graph))
                        retStmt.setOp(rightOp);
                } else if (rightOp instanceof Constant) {
                    retStmt.setOp(rightOp);
                } else // we rename the local to help splitting
                if (rightOp instanceof FieldRef) {
                    if (localUses == null)
                        localUses = LocalUses.Factory.newLocalUses(body, localDefs);
                    if (localUses.getUsesOf(assign).size() == 1) {
                        if (localCreation == null)
                            localCreation = new LocalCreation(body.getLocals(), "ret");
                        Local newLocal = localCreation.newLocal(leftOp.getType());
                        assign.setLeftOp(newLocal);
                        retStmt.setOp(newLocal);
                    }
                }
            }
        }
    }
}