/** * Make sure that all invoke special targets are cloned into the class from ancestors. This might * mean that we have to clone hidden methods, and change their names. So clone them in, and update * the clone to original map, and update the invoke special Also, this will update invoke specials * that target methods cloned in previous call to above cloneReachableNonHiddenAncestorMethods() */ private void cloneHiddenAncestorMethodsAndFixInvokeSpecial() { Set<SootClass> parents = SootUtils.getParents(clazz); boolean debug = false; // (clazz.getName().contains("ResultDisplayer")); boolean cloneAdded = false; do { cloneAdded = false; for (SootMethod method : clazz.getMethods()) { if (method.isAbstract() || method.isPhantom() || !method.isConcrete()) continue; if (debug) System.out.println(method); Body body = null; try { body = method.retrieveActiveBody(); } catch (Exception ex) { logger.info("Exception retrieving method body {}", ex); continue; } StmtBody stmtBody = (StmtBody) body; Chain units = stmtBody.getUnits(); Iterator stmtIt = units.iterator(); while (stmtIt.hasNext()) { Stmt stmt = (Stmt) stmtIt.next(); if (stmt.containsInvokeExpr() && stmt.getInvokeExpr() instanceof SpecialInvokeExpr) { SpecialInvokeExpr si = (SpecialInvokeExpr) stmt.getInvokeExpr(); SootMethod target = resolveSpecialInvokeTarget(si); // si.getMethod(); if (debug) System.out.printf("\t%s %s", si, target); if (clonedToOriginal.values().contains(target)) { // found target of invoke special, and it has been cloned, so change the invoke // special SootMethod cloneOfTarget = clonedToOriginal.inverse().get(target); si.setMethodRef(cloneOfTarget.makeRef()); if (debug) System.out.println("\tChange ref " + cloneOfTarget); } else if (parents.contains(target.getDeclaringClass())) { // target has not been cloned, but should be cloned, so clone it and change ref of // invoke String name = target.getName() + CLONED_METHOD_SUFFIX + (cloned_method_id++); SootMethod clonedMethod = cloneMethod(target, name); si.setMethodRef(clonedMethod.makeRef()); cloneAdded = true; if (debug) System.out.println("\tClone and Change ref " + clonedMethod); } } } } } while (cloneAdded); }
/** * Traverse the statements in the given body, looking for aggregation possibilities; that is, * given a def d and a use u, d has no other uses, u has no other defs, collapse d and u. * * <p>option: only-stack-locals; if this is true, only aggregate variables starting with $ */ protected void internalTransform(Body b, String phaseName, Map<String, String> options) { StmtBody body = (StmtBody) b; boolean onlyStackVars = PhaseOptions.getBoolean(options, "only-stack-locals"); int aggregateCount = 1; if (Options.v().time()) Timers.v().aggregationTimer.start(); boolean changed = false; Map<ValueBox, Zone> boxToZone = new HashMap<ValueBox, Zone>(body.getUnits().size() * 2 + 1, 0.7f); // Determine the zone of every box { Zonation zonation = new Zonation(body); for (Unit u : body.getUnits()) { Zone zone = zonation.getZoneOf(u); for (ValueBox box : u.getUseBoxes()) { boxToZone.put(box, zone); } for (ValueBox box : u.getDefBoxes()) { boxToZone.put(box, zone); } } } do { if (Options.v().verbose()) G.v() .out .println( "[" + body.getMethod().getName() + "] Aggregating iteration " + aggregateCount + "..."); // body.printTo(new java.io.PrintWriter(G.v().out, true)); changed = internalAggregate(body, boxToZone, onlyStackVars); aggregateCount++; } while (changed); if (Options.v().time()) Timers.v().aggregationTimer.end(); }
private static boolean internalAggregate( StmtBody body, Map<ValueBox, Zone> boxToZone, boolean onlyStackVars) { LocalUses localUses; LocalDefs localDefs; ExceptionalUnitGraph graph; boolean hadAggregation = false; Chain<Unit> units = body.getUnits(); graph = new ExceptionalUnitGraph(body); localDefs = new SmartLocalDefs(graph, new SimpleLiveLocals(graph)); localUses = new SimpleLocalUses(graph, localDefs); List<Unit> unitList = new PseudoTopologicalOrderer<Unit>().newList(graph, false); for (Unit u : unitList) { if (!(u instanceof AssignStmt)) continue; AssignStmt s = (AssignStmt) u; Value lhs = s.getLeftOp(); if (!(lhs instanceof Local)) continue; Local lhsLocal = (Local) lhs; if (onlyStackVars && !lhsLocal.getName().startsWith("$")) continue; List<UnitValueBoxPair> lu = localUses.getUsesOf(s); if (lu.size() != 1) continue; UnitValueBoxPair usepair = lu.get(0); Unit use = usepair.unit; ValueBox useBox = usepair.valueBox; List<Unit> ld = localDefs.getDefsOfAt(lhsLocal, use); if (ld.size() != 1) continue; // Check to make sure aggregation pair in the same zone if (boxToZone.get(s.getRightOpBox()) != boxToZone.get(usepair.valueBox)) { continue; } /* we need to check the path between def and use */ /* to see if there are any intervening re-defs of RHS */ /* in fact, we should check that this path is unique. */ /* if the RHS uses only locals, then we know what to do; if RHS has a method invocation f(a, b, c) or field access, we must ban field writes, other method calls and (as usual) writes to a, b, c. */ boolean cantAggr = false; boolean propagatingInvokeExpr = false; boolean propagatingFieldRef = false; boolean propagatingArrayRef = false; ArrayList<FieldRef> fieldRefList = new ArrayList<FieldRef>(); LinkedList<Value> localsUsed = new LinkedList<Value>(); for (ValueBox vb : s.getUseBoxes()) { Value v = vb.getValue(); if (v instanceof Local) localsUsed.add(v); else if (v instanceof InvokeExpr) propagatingInvokeExpr = true; else if (v instanceof ArrayRef) propagatingArrayRef = true; else if (v instanceof FieldRef) { propagatingFieldRef = true; fieldRefList.add((FieldRef) v); } } // look for a path from s to use in graph. // only look in an extended basic block, though. List<Unit> path = graph.getExtendedBasicBlockPathBetween(s, use); if (path == null) continue; Iterator<Unit> pathIt = path.iterator(); // skip s. if (pathIt.hasNext()) pathIt.next(); while (pathIt.hasNext() && !cantAggr) { Stmt between = (Stmt) (pathIt.next()); if (between != use) { // Check for killing definitions for (ValueBox vb : between.getDefBoxes()) { Value v = vb.getValue(); if (localsUsed.contains(v)) { cantAggr = true; break; } if (propagatingInvokeExpr || propagatingFieldRef || propagatingArrayRef) { if (v instanceof FieldRef) { if (propagatingInvokeExpr) { cantAggr = true; break; } else if (propagatingFieldRef) { // Can't aggregate a field access if passing a definition of a field // with the same name, because they might be aliased for (FieldRef fieldRef : fieldRefList) { if (((FieldRef) v).getField() == fieldRef.getField()) { cantAggr = true; break; } } } } else if (v instanceof ArrayRef) { if (propagatingInvokeExpr) { // Cannot aggregate an invoke expr past an array write cantAggr = true; break; } else if (propagatingArrayRef) { // cannot aggregate an array read past a write // this is somewhat conservative // (if types differ they may not be aliased) cantAggr = true; break; } } } } // Make sure not propagating past a {enter,exit}Monitor if (propagatingInvokeExpr && between instanceof MonitorStmt) cantAggr = true; } // Check for intervening side effects due to method calls if (propagatingInvokeExpr || propagatingFieldRef || propagatingArrayRef) { for (final ValueBox box : between.getUseBoxes()) { if (between == use && box == useBox) { // Reached use point, stop looking for // side effects break; } Value v = box.getValue(); if (v instanceof InvokeExpr || (propagatingInvokeExpr && (v instanceof FieldRef || v instanceof ArrayRef))) { cantAggr = true; break; } } } } // we give up: can't aggregate. if (cantAggr) { continue; } /* assuming that the d-u chains are correct, */ /* we need not check the actual contents of ld */ Value aggregatee = s.getRightOp(); if (usepair.valueBox.canContainValue(aggregatee)) { boolean wasSimpleCopy = isSimpleCopy(usepair.unit); usepair.valueBox.setValue(aggregatee); units.remove(s); hadAggregation = true; // clean up the tags. If s was not a simple copy, the new statement should get // the tags of s. // OK, this fix was wrong. The condition should not be // "If s was not a simple copy", but rather "If usepair.unit // was a simple copy". This way, when there's a load of a constant // followed by an invoke, the invoke gets the tags. if (wasSimpleCopy) { // usepair.unit.removeAllTags(); usepair.unit.addAllTagsOf(s); } } else { /* if(Options.v().verbose()) { G.v().out.println("[debug] failed aggregation"); G.v().out.println("[debug] tried to put "+aggregatee+ " into "+usepair.stmt + ": in particular, "+usepair.valueBox); G.v().out.println("[debug] aggregatee instanceof Expr: " +(aggregatee instanceof Expr)); }*/ } } return hadAggregation; }