private void searchRef(StringArrayRef ref, Loop loop) {
String temp_name = ref.getArrayName();
Iterator<Unit> iter = loop.getBodyBlocks().get(0).getBody().getUnits().iterator();
while (iter.hasNext()) {
Unit curr = iter.next();
if (defines(curr, temp_name) && curr instanceof AssignStmt) {
AssignStmt assign = (AssignStmt) curr;
Value right = assign.getRightOp();
if (right instanceof FieldRef) {
FieldRef field_ref = (FieldRef) right;
ref.setFieldSignature(field_ref.getField().getSignature());
ref.setField(field_ref.getField().getName());
}
}
}
}
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;
}
@Override
public Type appliesInternal(AndroidMethod method) {
SootMethod sm = getSootMethod(method);
// We are only interested in getters and setters
if (!sm.getName().startsWith("get") && !sm.getName().startsWith("set"))
return Type.NOT_SUPPORTED;
String baseName = sm.getName().substring(3);
String getterName = "get" + baseName;
String setterName = "set" + baseName;
try {
// Find the getter and the setter
SootMethod getter =
getSootMethod(new AndroidMethod(getterName, "", sm.getDeclaringClass().getName()));
SootMethod setter =
getSootMethod(new AndroidMethod(setterName, "", sm.getDeclaringClass().getName()));
if (getter == null || setter == null) return Type.FALSE;
if (!setter.isConcrete() || !getter.isConcrete()) return Type.NOT_SUPPORTED;
Body bodyGetter = null;
try {
bodyGetter = getter.retrieveActiveBody();
} catch (Exception ex) {
return Type.NOT_SUPPORTED;
}
// Find the local that gets returned
Local returnLocal = null;
for (Unit u : bodyGetter.getUnits())
if (u instanceof ReturnStmt) {
ReturnStmt ret = (ReturnStmt) u;
if (ret.getOp() instanceof Local) {
returnLocal = (Local) ret.getOp();
break;
}
}
if (returnLocal == null) return Type.FALSE;
// Find where the local is assigned a value in the code
List<FieldRef> accessPath = new ArrayList<FieldRef>();
Local returnBase = returnLocal;
while (returnBase != null)
for (Unit u : bodyGetter.getUnits()) {
if (u instanceof AssignStmt) {
AssignStmt assign = (AssignStmt) u;
if (assign.getLeftOp().equals(returnBase))
if (assign.getRightOp() instanceof InstanceFieldRef) {
InstanceFieldRef ref = (InstanceFieldRef) assign.getRightOp();
accessPath.add(0, ref);
returnBase = (Local) ref.getBase();
break;
} else returnBase = null;
} else if (u instanceof IdentityStmt) {
IdentityStmt id = (IdentityStmt) u;
if (id.getLeftOp().equals(returnBase)) returnBase = null;
}
}
if (accessPath.isEmpty()) return Type.FALSE;
/*
// Find the corresponding access path in the setter
for (Unit u : bodySetter.getUnits())
if (u instanceof AssignStmt) {
AssignStmt assign = (AssignStmt) u;
if (assign.getLeftOp() instanceof InstanceFieldRef
&& assign.getRightOp() instanceof Local) {
InstanceFieldRef iref = (InstanceFieldRef) assign.getLeftOp();
if (iref.getFieldRef().toString().equals(accessPath.get(accessPath.size() - 1).getFieldRef().toString())) {
// This is a starting point
boolean pathFound = false;
Local startLocal = (Local) iref.getBase();
int accessPathPos = accessPath.size() - 2;
while (startLocal != null) {
for (Unit u2 : bodySetter.getUnits()) {
if (u2 instanceof AssignStmt) {
AssignStmt assign2 = (AssignStmt) u2;
if (assign2.getLeftOp().equals(startLocal))
if (assign2.getRightOp() instanceof InstanceFieldRef) {
InstanceFieldRef ref = (InstanceFieldRef) assign2.getRightOp();
if (accessPath.get(accessPathPos--).getFieldRef().toString().equals(ref.getFieldRef().toString())) {
startLocal = (Local) ref.getBase();
break;
}
else
startLocal = null;
}
else
startLocal = null;
}
else if (u2 instanceof IdentityStmt) {
IdentityStmt id = (IdentityStmt) u2;
if (id.getLeftOp().equals(startLocal)) {
startLocal = null;
pathFound = true;
break;
}
}
}
}
if (pathFound) {
if (assign.getRightOp() instanceof Local) {
// Find the parameter being set
for (Unit u2 : bodySetter.getUnits())
if (u2 instanceof IdentityStmt) {
IdentityStmt id = (IdentityStmt) u2;
if (id.getLeftOp().equals(assign.getRightOp()))
return Type.TRUE;
}
}
break;
}
}
}
}
return Type.FALSE;
*/
return Type.TRUE;
} catch (Exception ex) {
System.err.println("Something went wrong:");
ex.printStackTrace();
return Type.NOT_SUPPORTED;
}
}