/**
* given a DelayabilityAnalysis and the computations of each unit, calculates the latest
* computation-point for each expression.<br>
* the <code>equivRhsMap</code> could be calculated on the fly, but it is <b>very</b> likely that
* it already exists (as similar maps are used for calculating Earliestness, Delayed,...<br>
* the shared set allows more efficient set-operations, when they the computation is merged with
* other analyses/computations.
*
* @param dg a ExceptionalUnitGraph
* @param delayed the delayability-analysis of the same graph.
* @param equivRhsMap all computations of the graph
* @param set the shared flowSet
*/
public LatestComputation(
UnitGraph unitGraph, DelayabilityAnalysis delayed, Map equivRhsMap, BoundedFlowSet set) {
unitToLatest = new HashMap<Unit, FlowSet>(unitGraph.size() + 1, 0.7f);
Iterator unitIt = unitGraph.iterator();
while (unitIt.hasNext()) {
/* create a new Earliest-list for each unit */
Unit currentUnit = (Unit) unitIt.next();
/* basically the latest-set is:
* (delayed) INTERSECT (comp UNION (UNION_successors ~Delayed)) =
* (delayed) MINUS ((INTERSECTION_successors Delayed) MINUS comp).
*/
FlowSet delaySet = (FlowSet) delayed.getFlowBefore(currentUnit);
/* Calculate (INTERSECTION_successors Delayed) */
FlowSet succCompSet = (FlowSet) set.topSet();
List succList = unitGraph.getSuccsOf(currentUnit);
Iterator succIt = succList.iterator();
while (succIt.hasNext()) {
Unit successor = (Unit) succIt.next();
succCompSet.intersection((FlowSet) delayed.getFlowBefore(successor), succCompSet);
}
/* remove the computation of this set: succCompSet is then:
* ((INTERSECTION_successors Delayed) MINUS comp) */
if (equivRhsMap.get(currentUnit) != null) succCompSet.remove(equivRhsMap.get(currentUnit));
/* make the difference: */
FlowSet latest = (FlowSet) delaySet.emptySet();
delaySet.difference(succCompSet, latest);
unitToLatest.put(currentUnit, latest);
}
}
/**
* 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();
}
protected void buildMaps(PegGraph pg) {
exceHandlers.addAll(pg.getExceHandlers());
startToThread.putAll(pg.getStartToThread());
startToAllocNodes.putAll(pg.getStartToAllocNodes());
startToBeginNodes.putAll(pg.getStartToBeginNodes());
waitingNodes.putAll(pg.getWaitingNodes());
notifyAll.putAll(pg.getNotifyAll());
canNotBeCompacted.addAll(pg.getCanNotBeCompacted());
synch.addAll(pg.getSynch());
threadNameToStart.putAll(pg.getThreadNameToStart());
specialJoin.addAll(pg.getSpecialJoin());
joinStmtToThread.putAll(pg.getJoinStmtToThread());
threadAllocSites.addAll(pg.getThreadAllocSites());
allocNodeToThread.putAll(pg.getAllocNodeToThread());
}
/**
* given a DelayabilityAnalysis and the computations of each unit, calculates the latest
* computation-point for each expression. the <code>equivRhsMap</code> could be calculated on the
* fly, but it is <b>very</b> likely that it already exists (as similar maps are used for
* calculating Earliestness, Delayed,...
*
* @param dg a ExceptionalUnitGraph
* @param delayed the delayability-analysis of the same graph.
* @param equivRhsMap all computations of the graph
*/
public LatestComputation(UnitGraph unitGraph, DelayabilityAnalysis delayed, Map equivRhsMap) {
this(
unitGraph,
delayed,
equivRhsMap,
new ArrayPackedSet(new CollectionFlowUniverse(equivRhsMap.values())));
}
protected void testJoinStmtToThread() {
System.out.println("=====test JoinStmtToThread");
Set maps = threadNameToStart.entrySet();
for (Iterator iter = maps.iterator(); iter.hasNext(); ) {
Map.Entry entry = (Map.Entry) iter.next();
Object key = entry.getKey();
System.out.println("---key= " + key);
System.out.println("value: " + entry.getValue());
}
System.out.println("=========JoinStmtToThread--ends--------");
}
public void computeMonitorObjs() {
Set maps = monitor.entrySet();
for (Iterator iter = maps.iterator(); iter.hasNext(); ) {
Map.Entry entry = (Map.Entry) iter.next();
FlowSet fs = (FlowSet) entry.getValue();
Iterator it = fs.iterator();
while (it.hasNext()) {
Object obj = it.next();
if (!monitorObjs.contains(obj)) monitorObjs.add(obj);
}
}
}
protected void testThreadNameToStart() {
System.out.println("=====test ThreadNameToStart");
Set maps = threadNameToStart.entrySet();
for (Iterator iter = maps.iterator(); iter.hasNext(); ) {
Map.Entry entry = (Map.Entry) iter.next();
Object key = entry.getKey();
System.out.println("---key= " + key);
JPegStmt stmt = (JPegStmt) entry.getValue();
Tag tag1 = (Tag) stmt.getTags().get(0);
System.out.println("value: " + tag1 + " " + stmt);
}
System.out.println("=========ThreadNameToStart--ends--------");
}
public void testMonitor() {
System.out.println("=====test monitor size: " + monitor.size());
Set maps = monitor.entrySet();
for (Iterator iter = maps.iterator(); iter.hasNext(); ) {
Map.Entry entry = (Map.Entry) iter.next();
String key = (String) entry.getKey();
System.out.println("---key= " + key);
FlowSet list = (FlowSet) entry.getValue();
if (list.size() > 0) {
System.out.println("**set: " + list.size());
Iterator it = list.iterator();
while (it.hasNext()) {
Object obj = it.next();
if (obj instanceof JPegStmt) {
JPegStmt stmt = (JPegStmt) obj;
Tag tag1 = (Tag) stmt.getTags().get(0);
System.out.println(tag1 + " " + stmt);
} else {
System.out.println("---list---");
Iterator listIt = ((List) obj).iterator();
while (listIt.hasNext()) {
Object oo = listIt.next();
if (oo instanceof JPegStmt) {
JPegStmt unit = (JPegStmt) oo;
Tag tag = (Tag) unit.getTags().get(0);
System.out.println(tag + " " + unit);
} else System.out.println(oo);
}
System.out.println("---list--end-");
}
}
}
}
System.out.println("=========monitor--ends--------");
}
/**
* returns the set of expressions, that have their latest computation just before <code>node
* </code>.
*
* @param node an Object of the flow-graph (in our case always a unit).
* @return a FlowSet containing the expressions.
*/
public Object getFlowBefore(Object node) {
return unitToLatest.get(node);
}
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;
}
