import IR.ClassDescriptor;
public class PrefetchAnalysis {
- State state;
- CallGraph callgraph;
- TypeUtil typeutil;
- LoopExit loop;
-
- Set<FlatNode> tovisit;
- public Hashtable<FlatNode, Hashtable<PrefetchPair, Double>> prefetch_hash;//holds all flatnodes and corresponding prefetch set
- public Hashtable<FlatNode, Hashtable<FlatNode, PairMap>> pmap_hash;//holds all flatnodes and mappings between child prefetch pair and parent prefetch pair
- public static final double PROB_DIFF = 0.05; //threshold for difference in probabilities during first phase of analysis
- public static final double ANALYSIS_THRESHOLD_PROB = 0.10; //threshold for prefetches to stop propagating during first phase of analysis
- public static final double PREFETCH_THRESHOLD_PROB = 0.30;//threshold for prefetches to stop propagating while applying prefetch rules during second phase of analysis
- public static int prefetchsiteid = 1; //initialized to one because there is a prefetch siteid 0 for starting remote thread
- LocalityAnalysis locality;
-
- public PrefetchAnalysis(State state, CallGraph callgraph, TypeUtil typeutil, LocalityAnalysis locality) {
- this.typeutil=typeutil;
- this.state=state;
- this.callgraph=callgraph;
- this.locality=locality;
- prefetch_hash = new Hashtable<FlatNode, Hashtable<PrefetchPair,Double>>();
- pmap_hash = new Hashtable<FlatNode, Hashtable<FlatNode, PairMap>>();
- this.loop=new LoopExit(state);
- DoPrefetch();
- }
-
-
- /** This function starts the prefetch analysis */
- private void DoPrefetch() {
- for (Iterator methodit=locality.getMethods().iterator();methodit.hasNext();) {
- MethodDescriptor md=(MethodDescriptor)methodit.next();
- if (state.excprefetch.contains(md.getClassMethodName()))
- continue; //Skip this method
- Hashtable<FlatNode, HashSet<PrefetchPair>> newprefetchset = new Hashtable<FlatNode, HashSet<PrefetchPair>>();
- FlatMethod fm=state.getMethodFlat(md);
- doFlatNodeAnalysis(fm);
- doInsPrefetchAnalysis(fm, newprefetchset);
- if(newprefetchset.size() > 0) {
- addFlatPrefetchNode(newprefetchset);
- }
- newprefetchset = null;
- }
- }
-
- /** This function calls analysis for every node in a method */
- private void doFlatNodeAnalysis(FlatMethod fm) {
- tovisit = fm.getNodeSet();
- Hashtable<PrefetchPair, Double> nodehash = new Hashtable<PrefetchPair, Double>();
- /* Create Empty Prefetch Sets for all flat nodes in the global hashtable */
- while(!tovisit.isEmpty()) {
- FlatNode fn = (FlatNode)tovisit.iterator().next();
- prefetch_hash.put(fn, nodehash);
- tovisit.remove(fn);
- }
-
- /* Visit and process nodes */
- tovisit = fm.getNodeSet();
- while(!tovisit.isEmpty()) {
- FlatNode fn = (FlatNode)tovisit.iterator().next();
- doChildNodeAnalysis(fm.getMethod(),fn);
- tovisit.remove(fn);
- }
- }
-
- /**
- * This function generates the prefetch sets for a given Flatnode considering the kind of node
- * It calls severals functions based on the kind of the node and
- * returns true: if the prefetch set has changed since last time the node was analysed
- * returns false : otherwise
- */
- private void doChildNodeAnalysis(MethodDescriptor md, FlatNode curr) {
- if (curr.kind()==FKind.FlatCondBranch) {
- processFlatCondBranch((FlatCondBranch)curr, md);
- } else {
- Hashtable<PrefetchPair, Double> child_prefetch_set_copy = new Hashtable<PrefetchPair, Double>();
- if(curr.numNext() != 0) {
- FlatNode child_node = curr.getNext(0);
- if(prefetch_hash.containsKey(child_node)) {
- child_prefetch_set_copy = (Hashtable<PrefetchPair,Double>) prefetch_hash.get(child_node).clone();
- }
-
- }
- switch(curr.kind()) {
- case FKind.FlatCall:
- processCall((FlatCall)curr,child_prefetch_set_copy);
- break;
-
- case FKind.FlatBackEdge:
- case FKind.FlatCheckNode:
- case FKind.FlatReturnNode:
- case FKind.FlatAtomicEnterNode:
- case FKind.FlatAtomicExitNode:
- case FKind.FlatFlagActionNode:
- case FKind.FlatGlobalConvNode:
- case FKind.FlatNop:
- case FKind.FlatNew:
- case FKind.FlatCastNode:
- case FKind.FlatTagDeclaration:
- processDefaultCase(curr,child_prefetch_set_copy);
- break;
- case FKind.FlatMethod:
- //TODO change it to take care of FlatMethod, Flatcalls
- processFlatMethod(curr, child_prefetch_set_copy);
- break;
- case FKind.FlatFieldNode:
- processFlatFieldNode(curr, child_prefetch_set_copy);
- break;
- case FKind.FlatElementNode:
- processFlatElementNode(curr, child_prefetch_set_copy);
- break;
- case FKind.FlatOpNode:
- processFlatOpNode(curr, child_prefetch_set_copy);
- break;
- case FKind.FlatLiteralNode:
- processFlatLiteralNode(curr, child_prefetch_set_copy);
- break;
- case FKind.FlatSetElementNode:
- processFlatSetElementNode(curr, child_prefetch_set_copy);
- break;
- case FKind.FlatSetFieldNode:
- processFlatSetFieldNode(curr, child_prefetch_set_copy);
- break;
- default:
- throw new Error("No such Flatnode kind");
- }
- }
- }
-
- /**This function compares all the prefetch pairs in a Prefetch set hashtable and
- * returns: true if something has changed in the new Prefetch set else
- * returns: false
- */
- private boolean comparePrefetchSets(Hashtable<PrefetchPair, Double> oldPrefetchSet, Hashtable<PrefetchPair, Double> newPrefetchSet) {
- if (oldPrefetchSet.size()!=newPrefetchSet.size())
- return true;
-
- for(Enumeration e = newPrefetchSet.keys();e.hasMoreElements();) {
- PrefetchPair pp = (PrefetchPair) e.nextElement();
- double newprob = newPrefetchSet.get(pp).doubleValue();
- if (!oldPrefetchSet.containsKey(pp))
- return true;
- double oldprob = oldPrefetchSet.get(pp).doubleValue();
-
- if((newprob - oldprob) > PROB_DIFF) {
- return true;
- }
- if (newprob >= PREFETCH_THRESHOLD_PROB && oldprob < PREFETCH_THRESHOLD_PROB) {
- return true;
- }
- if (oldprob>newprob) {
- System.out.println("ERROR:" + pp);
- System.out.println(oldprob + " -> "+ newprob);
- }
- }
- return false;
- }
-
- private void updatePairMap(FlatNode curr, PairMap pm, int index) {
- if (index>=curr.numNext())
- return;
- if (!pmap_hash.containsKey(curr.getNext(index))) {
- pmap_hash.put(curr.getNext(index), new Hashtable<FlatNode, PairMap>());
- }
- pmap_hash.get(curr.getNext(index)).put(curr, pm);
- }
-
- private void updatePrefetchSet(FlatNode curr, Hashtable<PrefetchPair, Double> newset) {
- Hashtable<PrefetchPair, Double>oldset=prefetch_hash.get(curr);
- if (comparePrefetchSets(oldset, newset)) {
- for(int i=0;i<curr.numPrev();i++) {
- tovisit.add(curr.getPrev(i));
- }
- prefetch_hash.put(curr, newset);
- }
- }
-
-
- /** This function processes the prefetch set of FlatFieldNode
- * It generates a new prefetch set after comparision with its children
- * Then compares it with its old prefetch set
- * If old prefetch set is not same as new prefetch set then enqueue the parents
- * of the current FlatFieldNode
- * */
- private void processFlatFieldNode(FlatNode curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
- Hashtable<PrefetchPair, Double> currcopy = new Hashtable<PrefetchPair, Double>();
- Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
- FlatFieldNode currffn = (FlatFieldNode) curr;
- PairMap pm = new PairMap();
-
- /* Do Self analysis of the current node*/
- FieldDescriptor currffn_field = currffn.getField();
- TempDescriptor currffn_src = currffn.getSrc();
- if (currffn_field.getType().isPtr()) {
- PrefetchPair pp = new PrefetchPair(currffn_src, (Descriptor) currffn_field);
- Double prob = new Double(1.0);
- tocompare.put(pp, prob);
- }
-
- /* Get each prefetch pair of the child and match it with the destination temp descriptor of curr FlatFieldNode */
-
- for (Enumeration ecld = child_prefetch_set_copy.keys();ecld.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
- if (childpp.base == currffn.getDst() && (childpp.getDesc()!= null)) {
- if (currffn.getField().getType().isPtr()) {
- ArrayList<Descriptor> newdesc = new ArrayList<Descriptor>();
- newdesc.add(currffn.getField());
- newdesc.addAll(childpp.desc);
- PrefetchPair newpp = new PrefetchPair(currffn.getSrc(), newdesc);
- Double newprob = child_prefetch_set_copy.get(childpp).doubleValue();
- if (tocompare.containsKey(newpp)) {
- Double oldprob=tocompare.get(newpp);
- newprob=1.0-(1.0-oldprob)*(1.0-newprob);
- }
- tocompare.put(newpp, newprob);
- pm.addPair(childpp, newpp);
- }
- //drop if not ptr
- } else if(childpp.base == currffn.getDst() && (childpp.getDesc() == null)) {
- //covered by current prefetch
- child_prefetch_set_copy.remove(childpp);
- } else if(childpp.containsTemp(currffn.getDst())) {
- child_prefetch_set_copy.remove(childpp);
- } else {
- Double newprob = child_prefetch_set_copy.get(childpp).doubleValue();
- if (tocompare.containsKey(childpp)) {
- Double oldprob=tocompare.get(childpp);
- newprob=1.0-(1.0-oldprob)*(1.0-newprob);
- }
- tocompare.put(childpp, newprob);
- pm.addPair(childpp, childpp);
- }
- }
-
- for(Iterator<PrefetchPair> it=tocompare.keySet().iterator();it.hasNext();) {
- PrefetchPair pp=it.next();
- if (tocompare.get(pp)<ANALYSIS_THRESHOLD_PROB)
- it.remove();
-
- }
-
- updatePairMap(curr, pm, 0);
- updatePrefetchSet(curr, tocompare);
- }
-
- /** This function processes the prefetch set of a FlatElementNode
- * It generates a new prefetch set after comparision with its children
- * It compares the old prefetch set with this new prefetch set and enqueues the parents
- * of the current node if change occurs and updates the global flatnode hash table
- * */
- private void processFlatElementNode(FlatNode curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
-
- Hashtable<PrefetchPair, Double> currcopy = new Hashtable<PrefetchPair, Double>();
- Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
- FlatElementNode currfen = (FlatElementNode) curr;
- PairMap pm = new PairMap();
-
-
- /* Do Self analysis of the current node*/
- TempDescriptor currfen_index = currfen.getIndex();
- IndexDescriptor idesc = new IndexDescriptor(currfen_index, 0);
- TempDescriptor currfen_src = currfen.getSrc();
- if(currfen.getDst().getType().isPtr()) {
- PrefetchPair pp = new PrefetchPair(currfen_src, (Descriptor) idesc);
- Double prob = new Double(1.0);
- currcopy.put(pp, prob);
- }
-
- /* Get each prefetch pair of the child and match it with the destination temp descriptor of curr FlatFieldNode */
- PrefetchPair currpp = null;
- for (Enumeration ecld = child_prefetch_set_copy.keys();ecld.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
- if (childpp.base == currfen.getDst() && (childpp.getDesc()!= null)) {
- if (currfen.getDst().getType().isPtr()) {
- ArrayList<Descriptor> newdesc = new ArrayList<Descriptor>();
- newdesc.add((Descriptor)idesc);
- newdesc.addAll(childpp.desc);
- PrefetchPair newpp = new PrefetchPair(currfen.getSrc(), newdesc);
- Double newprob = child_prefetch_set_copy.get(childpp).doubleValue();
- tocompare.put(newpp, newprob);
- pm.addPair(childpp, newpp);
- child_prefetch_set_copy.remove(childpp);
- /* Check for independence of prefetch pairs to compute new probability */
- if(child_prefetch_set_copy.containsKey(newpp)) {
- newprob = (1.0 - ((1.0 - child_prefetch_set_copy.get(newpp).doubleValue()) * (1.0 - tocompare.get(newpp).doubleValue())));
- if(newprob < ANALYSIS_THRESHOLD_PROB) {
- tocompare.remove(newpp);
- } else {
- tocompare.put(newpp, newprob);
- pm.addPair(newpp, newpp);
- }
- child_prefetch_set_copy.remove(newpp);
- }
- }
- } else if(childpp.base == currfen.getDst() && (childpp.getDesc() == null)) {
- child_prefetch_set_copy.remove(childpp);
- } else if(childpp.containsTemp(currfen.getDst())) {
- child_prefetch_set_copy.remove(childpp);
- } else {
- continue;
- }
- }
- /* Check if curr prefetch set and the child prefetch set have same prefetch pairs
- * if so calculate the new probability */
- for(Enumeration ecld = child_prefetch_set_copy.keys();ecld.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
- for(Enumeration e = currcopy.keys(); e.hasMoreElements();) {
- currpp = (PrefetchPair) e.nextElement();
- if(currpp.equals(childpp)) {
- pm.addPair(childpp, currpp);
- child_prefetch_set_copy.remove(childpp);
- break;
- }
- }
- }
-
- /* Merge child prefetch pairs */
- for (Enumeration ecld = child_prefetch_set_copy.keys();ecld.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
- tocompare.put(childpp, child_prefetch_set_copy.get(childpp).doubleValue());
- pm.addPair(childpp, childpp);
- child_prefetch_set_copy.remove(childpp);
- }
-
- /* Merge curr prefetch pairs */
- for (Enumeration e = currcopy.keys();e.hasMoreElements();) {
- currpp = (PrefetchPair) e.nextElement();
- tocompare.put(currpp, currcopy.get(currpp).doubleValue());
- currcopy.remove(currpp);
- }
-
- updatePairMap(curr, pm, 0);
- updatePrefetchSet(curr, tocompare);
- }
-
- /** This function processes the prefetch set of a FlatSetFieldNode
- * It generates a new prefetch set after comparision with its children
- * It compares the old prefetch set with this new prefetch set and enqueues the parents
- * of the current node if change occurs and then updates the global flatnode hash table
- * */
- private void processFlatSetFieldNode(FlatNode curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
- Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
- FlatSetFieldNode currfsfn = (FlatSetFieldNode) curr;
- PairMap pm = new PairMap();
-
- for (Enumeration ecld = child_prefetch_set_copy.keys();ecld.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
- if(childpp.base == currfsfn.getDst()) {
- int size = childpp.desc.size();
- if(size >=2) { /*e.g. x.f = g (with child prefetches x.f.g, x.f[0].j) */
- if((childpp.getDescAt(0) instanceof FieldDescriptor) && (childpp.getDescAt(0) == currfsfn.getField())) {
- ArrayList<Descriptor> newdesc = new ArrayList<Descriptor>();
- for(int i = 0;i<(childpp.desc.size()-1); i++) {
- newdesc.add(i,childpp.desc.get(i+1));
- }
- PrefetchPair newpp = new PrefetchPair(currfsfn.getSrc(), newdesc);
- Double newprob = child_prefetch_set_copy.get(childpp).doubleValue();
- tocompare.put(newpp, newprob);
- pm.addPair(childpp, newpp);
- child_prefetch_set_copy.remove(childpp);
- /* Check for independence of prefetch pairs in newly generated prefetch pair
- * to compute new probability */
- if(child_prefetch_set_copy.containsKey(newpp)) {
- newprob = (1.0 - ((1.0 - child_prefetch_set_copy.get(newpp).doubleValue()) * (1.0 - tocompare.get(newpp).doubleValue())));
- if(newprob < ANALYSIS_THRESHOLD_PROB) {
- tocompare.remove(newpp);
- } else {
- tocompare.put(newpp, newprob);
- pm.addPair(newpp, newpp);
- }
- child_prefetch_set_copy.remove(newpp);
- }
- }
- } else if(size==1) { /* e.g x.f = g (with child prefetch x.f) */
- if((childpp.getDescAt(0) instanceof FieldDescriptor) && (childpp.getDescAt(0) == currfsfn.getField())) {
- child_prefetch_set_copy.remove(childpp);
- }
- } else {
- continue;
- }
- }
- }
-
- /* Merge child prefetch pairs */
- for (Enumeration ecld = child_prefetch_set_copy.keys();ecld.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
- tocompare.put(childpp, child_prefetch_set_copy.get(childpp).doubleValue());
- pm.addPair(childpp, childpp);
- child_prefetch_set_copy.remove(childpp);
- }
-
- updatePairMap(curr, pm, 0);
- updatePrefetchSet(curr, tocompare);
- }
-
- /** This function processes the prefetch set of a FlatSetElementNode
- * It generates a new prefetch set after comparision with its children
- * It compares the old prefetch set with this new prefetch set and enqueues the parents
- * of the current node if change occurs and then updates the global flatnode hash table
- * */
- private void processFlatSetElementNode(FlatNode curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
- Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
- FlatSetElementNode currfsen = (FlatSetElementNode) curr;
- PairMap pm = new PairMap();
-
- for (Enumeration ecld = child_prefetch_set_copy.keys();ecld.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
- if (childpp.base == currfsen.getDst()){
- int sizedesc = childpp.desc.size();
- if((childpp.getDescAt(0) instanceof IndexDescriptor)) {
- int sizetempdesc = ((IndexDescriptor)(childpp.getDescAt(0))).tddesc.size();
- if(sizetempdesc == 1) {
- if((((IndexDescriptor)childpp.getDescAt(0)).tddesc.get(0) == currfsen.getIndex()) && (sizedesc>=2)) {
- /* For e.g. a[i] = g with child prefetch set a[i].r or a[i].r.f */
- ArrayList<Descriptor> newdesc = new ArrayList<Descriptor>();
- for(int i = 0;i<(childpp.desc.size()-1); i++) {
- newdesc.add(i,childpp.desc.get(i+1));
- }
- PrefetchPair newpp = new PrefetchPair(currfsen.getSrc(), newdesc);
- Double newprob = child_prefetch_set_copy.get(childpp).doubleValue();
- tocompare.put(newpp, newprob);
- pm.addPair(childpp, newpp);
- child_prefetch_set_copy.remove(childpp);
- /* Check for independence of prefetch pairs to compute new probability */
- if(child_prefetch_set_copy.containsKey(newpp)) {
- newprob = (1.0 - ((1.0 - child_prefetch_set_copy.get(newpp).doubleValue()) * (1.0 - tocompare.get(newpp).doubleValue())));
- if(newprob < ANALYSIS_THRESHOLD_PROB) {
- tocompare.remove(newpp);
- } else {
- tocompare.put(newpp, newprob);
- pm.addPair(newpp, newpp);
- }
- child_prefetch_set_copy.remove(newpp);
- }
- } else if((((IndexDescriptor)childpp.getDescAt(0)).tddesc.get(0) == currfsen.getIndex()) && (sizedesc==1))
- /* For e.g. a[i] = g with child prefetch set a[i] */
- child_prefetch_set_copy.remove(childpp);
- } else {
- continue;
- }
- }
- }
- }
- /* Merge child prefetch pairs */
- for (Enumeration ecld = child_prefetch_set_copy.keys();ecld.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
- tocompare.put(childpp, child_prefetch_set_copy.get(childpp).doubleValue());
- pm.addPair(childpp, childpp);
- child_prefetch_set_copy.remove(childpp);
- }
-
- updatePairMap(curr, pm, 0);
- updatePrefetchSet(curr, tocompare);
- }
-
- /** This function applies rules and does analysis for a FlatOpNode
- * And updates the global prefetch hashtable
- * */
- private void processFlatOpNode(FlatNode curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
- int index;
- Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
- FlatOpNode currfopn = (FlatOpNode) curr;
- PairMap pm = new PairMap();
-
- if(currfopn.getOp().getOp() == Operation.ASSIGN) {
- for (Enumeration ecld = child_prefetch_set_copy.keys();ecld.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
- PrefetchPair copyofchildpp = (PrefetchPair) childpp.clone();
-
- /* For cases like x=y with child prefetch set x[i].z,x.g*/
- if(childpp.base == currfopn.getDest()) {
- ArrayList<Descriptor> newdesc = new ArrayList<Descriptor>();
- newdesc.addAll(childpp.desc);
- PrefetchPair newpp = new PrefetchPair(currfopn.getLeft(), newdesc);
- Double newprob = child_prefetch_set_copy.get(childpp).doubleValue();
- tocompare.put(newpp, newprob);
- pm.addPair(childpp, newpp);
- child_prefetch_set_copy.remove(childpp);
- /* Check for independence of prefetch pairs to compute new probability */
- if(child_prefetch_set_copy.containsKey(newpp)) {
- newprob = (1.0 - ((1.0 - child_prefetch_set_copy.get(newpp).doubleValue()) * (1.0 - tocompare.get(newpp).doubleValue())));
- if(newprob < ANALYSIS_THRESHOLD_PROB) {
- tocompare.remove(newpp);
- } else {
- tocompare.put(newpp, newprob);
- pm.addPair(newpp, newpp);
- }
- child_prefetch_set_copy.remove(newpp);
- }
- /* For cases like x=y with child prefetch set r[x].p, r[p+x].q where x is a tempdescriptor*/
- } else if(copyofchildpp.containsTemp(currfopn.getDest())) {
- PrefetchPair newpp=copyofchildpp.replaceTemp(currfopn.getDest(), new TempDescriptor[] {currfopn.getLeft()});
- Double newprob = child_prefetch_set_copy.get(childpp).doubleValue();
- tocompare.put(newpp, newprob);
- pm.addPair(childpp, newpp);
- child_prefetch_set_copy.remove(childpp);
- /* Check for independence of prefetch pairs to compute new probability*/
- if(child_prefetch_set_copy.containsKey(newpp)) {
- newprob = (1.0 - ((1.0 - child_prefetch_set_copy.get(newpp).doubleValue()) * (1.0 - tocompare.get(newpp).doubleValue())));
- if(newprob < ANALYSIS_THRESHOLD_PROB) {
- tocompare.remove(newpp);
- } else {
- tocompare.put(newpp, newprob);
- pm.addPair(newpp, newpp);
- }
- child_prefetch_set_copy.remove(newpp);
- }
- newpp = null;
- } else {
- continue;
- }
- }
- //case i = i+z with child prefetch set a[i].x
- } else if(currfopn.getRight()!=null && (currfopn.getOp().getOp() == Operation.ADD)) {
- for (Enumeration ecld = child_prefetch_set_copy.keys();ecld.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
- PrefetchPair copyofchildpp = (PrefetchPair) childpp.clone();
-
- if(copyofchildpp.containsTemp(currfopn.getDest())) {
- PrefetchPair newpp=copyofchildpp.replaceTemp(currfopn.getDest(), new TempDescriptor[] {currfopn.getLeft(), currfopn.getRight()});
- Double newprob = child_prefetch_set_copy.get(childpp).doubleValue();
- tocompare.put(newpp, newprob);
- pm.addPair(childpp, newpp);
- child_prefetch_set_copy.remove(childpp);
- /* Check for independence of prefetch pairs to compute new probability*/
- if(child_prefetch_set_copy.containsKey(newpp)) {
- newprob = (1.0 - ((1.0 - child_prefetch_set_copy.get(newpp).doubleValue()) * (1.0 - tocompare.get(newpp).doubleValue())));
- if(newprob < ANALYSIS_THRESHOLD_PROB) {
- tocompare.remove(newpp);
- } else {
- tocompare.put(newpp, newprob);
- pm.addPair(newpp, newpp);
- }
- child_prefetch_set_copy.remove(newpp);
- }
- } else {
- continue;
- }
- }
- } else if(currfopn.getRight()!=null && (currfopn.getOp().getOp() == Operation.SUB)) {
- for(Enumeration ecld = child_prefetch_set_copy.keys();ecld.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
- if(childpp.containsTemp(currfopn.getDest())) {
- child_prefetch_set_copy.remove(childpp);
+ State state;
+ CallGraph callgraph;
+ TypeUtil typeutil;
+ LoopExit loop;
+
+ Set<FlatNode> tovisit;
+ public Hashtable<FlatNode, Hashtable<PrefetchPair, Double>> prefetch_hash; //holds all flatnodes and corresponding prefetch set
+ public Hashtable<FlatNode, Hashtable<FlatNode, PairMap>> pmap_hash; //holds all flatnodes and mappings between child prefetch pair and parent prefetch pair
+ public static final double PROB_DIFF = 0.05; //threshold for difference in probabilities during first phase of analysis
+ public static final double ANALYSIS_THRESHOLD_PROB = 0.10; //threshold for prefetches to stop propagating during first phase of analysis
+ public static final double PREFETCH_THRESHOLD_PROB = 0.30; //threshold for prefetches to stop propagating while applying prefetch rules during second phase of analysis
+ public static int prefetchsiteid = 1; //initialized to one because there is a prefetch siteid 0 for starting remote thread
+ LocalityAnalysis locality;
+
+ public PrefetchAnalysis(State state, CallGraph callgraph, TypeUtil typeutil, LocalityAnalysis locality) {
+ this.typeutil=typeutil;
+ this.state=state;
+ this.callgraph=callgraph;
+ this.locality=locality;
+ prefetch_hash = new Hashtable<FlatNode, Hashtable<PrefetchPair,Double>>();
+ pmap_hash = new Hashtable<FlatNode, Hashtable<FlatNode, PairMap>>();
+ this.loop=new LoopExit(state);
+ DoPrefetch();
+ }
+
+
+ /** This function starts the prefetch analysis */
+ private void DoPrefetch() {
+ for (Iterator methodit=locality.getMethods().iterator(); methodit.hasNext(); ) {
+ MethodDescriptor md=(MethodDescriptor)methodit.next();
+ if (state.excprefetch.contains(md.getClassMethodName()))
+ continue; //Skip this method
+ Hashtable<FlatNode, HashSet<PrefetchPair>> newprefetchset = new Hashtable<FlatNode, HashSet<PrefetchPair>>();
+ FlatMethod fm=state.getMethodFlat(md);
+ doFlatNodeAnalysis(fm);
+ doInsPrefetchAnalysis(fm, newprefetchset);
+ if(newprefetchset.size() > 0) {
+ addFlatPrefetchNode(newprefetchset);
+ }
+ newprefetchset = null;
+ }
+ }
+
+ /** This function calls analysis for every node in a method */
+ private void doFlatNodeAnalysis(FlatMethod fm) {
+ tovisit = fm.getNodeSet();
+ Hashtable<PrefetchPair, Double> nodehash = new Hashtable<PrefetchPair, Double>();
+ /* Create Empty Prefetch Sets for all flat nodes in the global hashtable */
+ while(!tovisit.isEmpty()) {
+ FlatNode fn = (FlatNode)tovisit.iterator().next();
+ prefetch_hash.put(fn, nodehash);
+ tovisit.remove(fn);
+ }
+
+ /* Visit and process nodes */
+ tovisit = fm.getNodeSet();
+ while(!tovisit.isEmpty()) {
+ FlatNode fn = (FlatNode)tovisit.iterator().next();
+ tovisit.remove(fn);
+
+ doChildNodeAnalysis(fm.getMethod(),fn);
+ }
+ }
+
+ /**
+ * This function generates the prefetch sets for a given Flatnode considering the kind of node
+ * It calls severals functions based on the kind of the node and
+ * returns true: if the prefetch set has changed since last time the node was analysed
+ * returns false : otherwise
+ */
+ private void doChildNodeAnalysis(MethodDescriptor md, FlatNode curr) {
+ if (curr.kind()==FKind.FlatCondBranch) {
+ processFlatCondBranch((FlatCondBranch)curr, md);
+ } else {
+ Hashtable<PrefetchPair, Double> child_prefetch_set_copy = new Hashtable<PrefetchPair, Double>();
+ if(curr.numNext() != 0) {
+ FlatNode child_node = curr.getNext(0);
+ if(prefetch_hash.containsKey(child_node)) {
+ child_prefetch_set_copy = (Hashtable<PrefetchPair,Double>)prefetch_hash.get(child_node).clone();
+ }
+
+ }
+ switch(curr.kind()) {
+ case FKind.FlatCall:
+ processCall((FlatCall)curr,child_prefetch_set_copy);
+ break;
+
+ case FKind.FlatBackEdge:
+ case FKind.FlatCheckNode:
+ case FKind.FlatReturnNode:
+ case FKind.FlatAtomicEnterNode:
+ case FKind.FlatAtomicExitNode:
+ case FKind.FlatFlagActionNode:
+ case FKind.FlatGlobalConvNode:
+ case FKind.FlatNop:
+ case FKind.FlatExit:
+ case FKind.FlatNew:
+ case FKind.FlatCastNode:
+ case FKind.FlatTagDeclaration:
+ case FKind.FlatInstanceOfNode:
+ processDefaultCase(curr,child_prefetch_set_copy);
+ break;
+
+ case FKind.FlatMethod:
+ //TODO change it to take care of FlatMethod, Flatcalls
+ processFlatMethod(curr, child_prefetch_set_copy);
+ break;
+
+ case FKind.FlatFieldNode:
+ processFlatFieldNode(curr, child_prefetch_set_copy);
+ break;
+
+ case FKind.FlatElementNode:
+ processFlatElementNode(curr, child_prefetch_set_copy);
+ break;
+
+ case FKind.FlatOpNode:
+ processFlatOpNode(curr, child_prefetch_set_copy);
+ break;
+
+ case FKind.FlatLiteralNode:
+ processFlatLiteralNode(curr, child_prefetch_set_copy);
+ break;
+
+ case FKind.FlatSetElementNode:
+ processFlatSetElementNode(curr, child_prefetch_set_copy);
+ break;
+
+ case FKind.FlatSetFieldNode:
+ processFlatSetFieldNode(curr, child_prefetch_set_copy);
+ break;
+
+ case FKind.FlatOffsetNode:
+ processDefaultCase(curr,child_prefetch_set_copy);
+ break;
+
+ default:
+ throw new Error("No such Flatnode kind");
+ }
+ }
+ }
+
+ /**This function compares all the prefetch pairs in a Prefetch set hashtable and
+ * returns: true if something has changed in the new Prefetch set else
+ * returns: false
+ */
+ private boolean comparePrefetchSets(Hashtable<PrefetchPair, Double> oldPrefetchSet, Hashtable<PrefetchPair, Double> newPrefetchSet) {
+ if (oldPrefetchSet.size()!=newPrefetchSet.size())
+ return true;
+
+ for(Enumeration e = newPrefetchSet.keys(); e.hasMoreElements(); ) {
+ PrefetchPair pp = (PrefetchPair) e.nextElement();
+ double newprob = newPrefetchSet.get(pp).doubleValue();
+ if (!oldPrefetchSet.containsKey(pp))
+ return true;
+ double oldprob = oldPrefetchSet.get(pp).doubleValue();
+
+ if((newprob - oldprob) > PROB_DIFF) {
+ return true;
+ }
+ if (newprob >= PREFETCH_THRESHOLD_PROB && oldprob < PREFETCH_THRESHOLD_PROB) {
+ return true;
+ }
+ if (oldprob>newprob) {
+ System.out.println("ERROR:" + pp);
+ System.out.println(oldprob + " -> "+ newprob);
+ }
+ }
+ return false;
+ }
+
+ private void updatePairMap(FlatNode curr, PairMap pm, int index) {
+ if (index>=curr.numNext())
+ return;
+ if (!pmap_hash.containsKey(curr.getNext(index))) {
+ pmap_hash.put(curr.getNext(index), new Hashtable<FlatNode, PairMap>());
+ }
+ pmap_hash.get(curr.getNext(index)).put(curr, pm);
+ }
+
+ private void updatePrefetchSet(FlatNode curr, Hashtable<PrefetchPair, Double> newset) {
+ Hashtable<PrefetchPair, Double>oldset=prefetch_hash.get(curr);
+ if (comparePrefetchSets(oldset, newset)) {
+ for(int i=0; i<curr.numPrev(); i++) {
+ tovisit.add(curr.getPrev(i));
+ }
+ prefetch_hash.put(curr, newset);
+ }
+ }
+
+
+ /** This function processes the prefetch set of FlatFieldNode
+ * It generates a new prefetch set after comparision with its children
+ * Then compares it with its old prefetch set
+ * If old prefetch set is not same as new prefetch set then enqueue the parents
+ * of the current FlatFieldNode
+ * */
+ private void processFlatFieldNode(FlatNode curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
+ Hashtable<PrefetchPair, Double> currcopy = new Hashtable<PrefetchPair, Double>();
+ Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
+ FlatFieldNode currffn = (FlatFieldNode) curr;
+ PairMap pm = new PairMap();
+
+ /* Do Self analysis of the current node*/
+ FieldDescriptor currffn_field = currffn.getField();
+ TempDescriptor currffn_src = currffn.getSrc();
+ if (currffn_field.getType().isPtr()) {
+ PrefetchPair pp = new PrefetchPair(currffn_src, (Descriptor) currffn_field);
+ Double prob = new Double(1.0);
+ tocompare.put(pp, prob);
+ }
+
+ /* Get each prefetch pair of the child and match it with the destination temp descriptor of curr FlatFieldNode */
+
+ for (Enumeration ecld = child_prefetch_set_copy.keys(); ecld.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
+ if (childpp.base == currffn.getDst() && (childpp.getDesc()!= null)) {
+ if (currffn.getField().getType().isPtr()) {
+ ArrayList<Descriptor> newdesc = new ArrayList<Descriptor>();
+ newdesc.add(currffn.getField());
+ newdesc.addAll(childpp.desc);
+ PrefetchPair newpp = new PrefetchPair(currffn.getSrc(), newdesc);
+ Double newprob = child_prefetch_set_copy.get(childpp).doubleValue();
+ if (tocompare.containsKey(newpp)) {
+ Double oldprob=tocompare.get(newpp);
+ newprob=1.0-(1.0-oldprob)*(1.0-newprob);
+ }
+ tocompare.put(newpp, newprob);
+ pm.addPair(childpp, newpp);
+ }
+ //drop if not ptr
+ } else if(childpp.base == currffn.getDst() && (childpp.getDesc() == null)) {
+ //covered by current prefetch
+ child_prefetch_set_copy.remove(childpp);
+ } else if(childpp.containsTemp(currffn.getDst())) {
+ child_prefetch_set_copy.remove(childpp);
+ } else {
+ Double newprob = child_prefetch_set_copy.get(childpp).doubleValue();
+ if (tocompare.containsKey(childpp)) {
+ Double oldprob=tocompare.get(childpp);
+ newprob=1.0-(1.0-oldprob)*(1.0-newprob);
+ }
+ tocompare.put(childpp, newprob);
+ pm.addPair(childpp, childpp);
+ }
+ }
+
+ for(Iterator<PrefetchPair> it=tocompare.keySet().iterator(); it.hasNext(); ) {
+ PrefetchPair pp=it.next();
+ if (tocompare.get(pp)<ANALYSIS_THRESHOLD_PROB)
+ it.remove();
+
+ }
+
+ updatePairMap(curr, pm, 0);
+ updatePrefetchSet(curr, tocompare);
+ }
+
+ /** This function processes the prefetch set of a FlatElementNode
+ * It generates a new prefetch set after comparision with its children
+ * It compares the old prefetch set with this new prefetch set and enqueues the parents
+ * of the current node if change occurs and updates the global flatnode hash table
+ * */
+ private void processFlatElementNode(FlatNode curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
+
+ Hashtable<PrefetchPair, Double> currcopy = new Hashtable<PrefetchPair, Double>();
+ Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
+ FlatElementNode currfen = (FlatElementNode) curr;
+ PairMap pm = new PairMap();
+
+
+ /* Do Self analysis of the current node*/
+ TempDescriptor currfen_index = currfen.getIndex();
+ IndexDescriptor idesc = new IndexDescriptor(currfen_index, 0);
+ TempDescriptor currfen_src = currfen.getSrc();
+ if(currfen.getDst().getType().isPtr()) {
+ PrefetchPair pp = new PrefetchPair(currfen_src, (Descriptor) idesc);
+ Double prob = new Double(1.0);
+ currcopy.put(pp, prob);
+ }
+
+ /* Get each prefetch pair of the child and match it with the destination temp descriptor of curr FlatFieldNode */
+ PrefetchPair currpp = null;
+ for (Enumeration ecld = child_prefetch_set_copy.keys(); ecld.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
+ if (childpp.base == currfen.getDst() && (childpp.getDesc()!= null)) {
+ if (currfen.getDst().getType().isPtr()) {
+ ArrayList<Descriptor> newdesc = new ArrayList<Descriptor>();
+ newdesc.add((Descriptor)idesc);
+ newdesc.addAll(childpp.desc);
+ PrefetchPair newpp = new PrefetchPair(currfen.getSrc(), newdesc);
+ Double newprob = child_prefetch_set_copy.get(childpp).doubleValue();
+ tocompare.put(newpp, newprob);
+ pm.addPair(childpp, newpp);
+ child_prefetch_set_copy.remove(childpp);
+ /* Check for independence of prefetch pairs to compute new probability */
+ if(child_prefetch_set_copy.containsKey(newpp)) {
+ newprob = (1.0 - ((1.0 - child_prefetch_set_copy.get(newpp).doubleValue()) * (1.0 - tocompare.get(newpp).doubleValue())));
+ if(newprob < ANALYSIS_THRESHOLD_PROB) {
+ tocompare.remove(newpp);
+ } else {
+ tocompare.put(newpp, newprob);
+ pm.addPair(newpp, newpp);
}
+ child_prefetch_set_copy.remove(newpp);
+ }
}
- } else {
- //FIXME Is not taken care of for cases like x = -y followed by a[x].i
- }
-
- /* Merge child prefetch pairs */
- for (Enumeration ecld = child_prefetch_set_copy.keys();ecld.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
- tocompare.put(childpp, child_prefetch_set_copy.get(childpp).doubleValue());
- pm.addPair(childpp, childpp);
- child_prefetch_set_copy.remove(childpp);
- }
-
- updatePairMap(curr, pm, 0);
- updatePrefetchSet(curr, tocompare);
- }
-
- /** This function processes a FlatLiteralNode where cases such as
- * for e.g. i = 0 with child prefetch sets a[i].r, a[j+i].r or a[j].b[i].r
- * are handled */
- private void processFlatLiteralNode(FlatNode curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
- Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
- FlatLiteralNode currfln = (FlatLiteralNode) curr;
- PairMap pm = new PairMap();
-
- if(currfln.getType().isIntegerType()) {
- for (Enumeration ecld = child_prefetch_set_copy.keys();ecld.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
- PrefetchPair copyofchildpp = (PrefetchPair) childpp.clone();
- if(copyofchildpp.containsTemp(currfln.getDst())) {
- ArrayList<Descriptor> copychilddesc = (ArrayList<Descriptor>) copyofchildpp.getDesc();
- int sizetempdesc = copychilddesc.size();
- for(ListIterator it = copychilddesc.listIterator();it.hasNext();) {
- Object o = it.next();
- if(o instanceof IndexDescriptor) {
- ArrayList<TempDescriptor> td = (ArrayList<TempDescriptor>)((IndexDescriptor)o).tddesc;
- int sizetddesc = td.size();
- if(td.contains(currfln.getDst())) {
- int index = td.indexOf(currfln.getDst());
- td.remove(index);
- ((IndexDescriptor)o).offset += (Integer)currfln.getValue();
- }
- }
- }
- ArrayList<Descriptor> newdesc = new ArrayList<Descriptor>();
- newdesc.addAll(copychilddesc);
- PrefetchPair newpp = new PrefetchPair(childpp.base, newdesc);
- Double newprob = (child_prefetch_set_copy.get(childpp)).doubleValue();
- tocompare.put(newpp, newprob);
- pm.addPair(childpp, newpp);
- child_prefetch_set_copy.remove(childpp);
- /* Check for independence of prefetch pairs to compute new probability */
- if(child_prefetch_set_copy.containsKey(newpp)) {
- newprob = (1.0 - ((1.0 - child_prefetch_set_copy.get(newpp).doubleValue()) * (1.0 - tocompare.get(newpp).doubleValue())));
- if(newprob < ANALYSIS_THRESHOLD_PROB) {
- tocompare.remove(newpp);
- } else {
- tocompare.put(newpp, newprob);
- pm.addPair(newpp, newpp);
- }
- child_prefetch_set_copy.remove(newpp);
- }
- }
- }
- }
-
- /* Merge child prefetch pairs */
- for (Enumeration ecld = child_prefetch_set_copy.keys();ecld.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
- tocompare.put(childpp, child_prefetch_set_copy.get(childpp).doubleValue());
- pm.addPair(childpp, childpp);
- child_prefetch_set_copy.remove(childpp);
- }
-
- updatePairMap(curr, pm, 0);
- updatePrefetchSet(curr, tocompare);
- }
-
- /** This function processes a FlatMethod where the method propagates
- * the entire prefetch set of its child node */
- private void processFlatMethod(FlatNode curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
- Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
- FlatMethod currfm = (FlatMethod) curr;
- PairMap pm = new PairMap();
-
- /* Merge child prefetch pairs */
- for (Enumeration ecld = child_prefetch_set_copy.keys();ecld.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
- tocompare.put(childpp, child_prefetch_set_copy.get(childpp).doubleValue());
- pm.addPair(childpp, childpp);
- }
-
- updatePairMap(curr, pm, 0);
- updatePrefetchSet(curr, tocompare);
- }
-
- /** This function handles the processes the FlatNode of type FlatCondBranch
- * It combines prefetches of both child elements and create a new hash table called
- * branch_prefetch_set to contains the entries of both its children
- */
- private void processFlatCondBranch(FlatCondBranch fcb, MethodDescriptor md) {
- Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();//temporary hash table
- PairMap truepm = new PairMap();
- PairMap falsepm = new PairMap();
- Hashtable<PrefetchPair, Double> truechild=prefetch_hash.get(fcb.getNext(0));
- Hashtable<PrefetchPair, Double> falsechild=prefetch_hash.get(fcb.getNext(1));
-
- HashSet<PrefetchPair> allpp=new HashSet<PrefetchPair>();
- allpp.addAll(truechild.keySet());
- allpp.addAll(falsechild.keySet());
-
- for(Iterator<PrefetchPair> ppit=allpp.iterator();ppit.hasNext();) {
- PrefetchPair pp=ppit.next();
- double trueprob=0,falseprob=0;
- if (truechild.containsKey(pp))
- trueprob=truechild.get(pp).doubleValue();
- if (falsechild.containsKey(pp))
- falseprob=falsechild.get(pp).doubleValue();
-
- double newprob=trueprob*fcb.getTrueProb()+falseprob*fcb.getFalseProb();
- if (loop.isLoopingBranch(md,fcb)&&
- newprob<falseprob) {
- newprob=falseprob;
- }
-
- if(newprob < ANALYSIS_THRESHOLD_PROB) //Skip pp that are below threshold
- continue;
-
- tocompare.put(pp, newprob);
- if (truechild.containsKey(pp))
- truepm.addPair(pp, pp);
-
- if (falsechild.containsKey(pp))
- falsepm.addPair(pp, pp);
-
- }
-
- updatePairMap(fcb, truepm, 0);
- updatePairMap(fcb, falsepm, 1);
- updatePrefetchSet(fcb, tocompare);
- }
-
- /** If FlatNode is not concerned with the prefetch set of its Child then propagate
- * prefetches up the FlatNode*/
- private void processDefaultCase(FlatNode curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
- PairMap pm = new PairMap();
- Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
-
- /* Propagate all child nodes */
- nexttemp:
- for(Enumeration e = child_prefetch_set_copy.keys(); e.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) e.nextElement();
- TempDescriptor[] writearray=curr.writesTemps();
- for(int i=0;i<writearray.length;i++) {
- TempDescriptor wtd=writearray[i];
- if(childpp.base == wtd||
- childpp.containsTemp(wtd))
- continue nexttemp;
- }
- tocompare.put(childpp, child_prefetch_set_copy.get(childpp));
- pm.addPair(childpp, childpp);
- }
-
- updatePairMap(curr, pm, 0);
- updatePrefetchSet(curr, tocompare);
- }
-
- /** If FlatNode is not concerned with the prefetch set of its Child then propagate
- * prefetches up the FlatNode*/
- private void processCall(FlatCall curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
- PairMap pm = new PairMap();
- Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
-
- /* Don't propagate prefetches across cache clear */
- if (!curr.getMethod().getClassMethodName().equals("System.clearPrefetchCache")) {
- /* Propagate all child nodes */
- nexttemp:
- for(Enumeration e = child_prefetch_set_copy.keys(); e.hasMoreElements();) {
- PrefetchPair childpp = (PrefetchPair) e.nextElement();
- TempDescriptor[] writearray=curr.writesTemps();
- for(int i=0;i<writearray.length;i++) {
- TempDescriptor wtd=writearray[i];
- if(childpp.base == wtd||
- childpp.containsTemp(wtd))
- continue nexttemp;
- }
- tocompare.put(childpp, child_prefetch_set_copy.get(childpp));
- pm.addPair(childpp, childpp);
- }
-
- }
- updatePairMap(curr, pm, 0);
- updatePrefetchSet(curr, tocompare);
- }
-
- /** This function prints the Prefetch pairs of a given flatnode */
- private void printPrefetchPairs(FlatNode fn) {
- System.out.println(fn);
- if(prefetch_hash.containsKey(fn)) {
- System.out.print("Prefetch" + "(");
- Hashtable<PrefetchPair, Double> currhash = (Hashtable) prefetch_hash.get(fn);
- for(Enumeration pphash= currhash.keys(); pphash.hasMoreElements();) {
- PrefetchPair pp = (PrefetchPair) pphash.nextElement();
- System.out.print(pp.toString() + ", ");
- }
- System.out.println(")");
- } else {
- System.out.println("Flatnode is currently not present in the global hash: Prefetch Set is Empty");
- }
- }
-
- private void doInsPrefetchAnalysis(FlatMethod fm, Hashtable<FlatNode, HashSet<PrefetchPair>> newprefetchset) {
- Hashtable<FlatNode, HashSet<PrefetchPair>> pset1_hash = new Hashtable<FlatNode, HashSet<PrefetchPair>>();
- HashSet<PrefetchPair> pset1_init = new HashSet<PrefetchPair>();
- LinkedList<FlatNode> newtovisit = new LinkedList<FlatNode>();
- LinkedList<FlatNode> newvisited = new LinkedList<FlatNode>();
-
- newtovisit.addLast((FlatNode)fm);
- while(!newtovisit.isEmpty()) {
- FlatNode fn = (FlatNode) newtovisit.iterator().next();
- newtovisit.remove(0);
- pset1_hash.put(fn, pset1_init); //Initialize pset1_hash
- newvisited.addLast(fn);
- for(int i=0; i<fn.numNext(); i++) {
- FlatNode nn = fn.getNext(i);
- if(!newtovisit.contains(nn) && !newvisited.contains(nn)){
- newtovisit.addLast(nn);
- }
- }
- }
-
- /* Start with a top down sorted order of nodes */
- while(!newvisited.isEmpty()) {
- applyPrefetchInsertRules((FlatNode) newvisited.getFirst(), newvisited, pset1_hash, newprefetchset);
- newvisited.remove(0);
- }
- delSubsetPPairs(newprefetchset);
- }
-
- /** This function deletes the smaller prefetch pair subset from a list of prefetch pairs
- * for e.g. if there are 2 prefetch pairs a.b.c.d and a.b.c for a given flatnode
- * then this function drops a.b.c from the prefetch set of the flatnode */
- private void delSubsetPPairs(Hashtable<FlatNode, HashSet<PrefetchPair>> newprefetchset) {
- for (Enumeration e = newprefetchset.keys();e.hasMoreElements();) {
- FlatNode fn = (FlatNode) e.nextElement();
- Set<PrefetchPair> ppairs = newprefetchset.get(fn);
- Set<PrefetchPair> toremove=new HashSet<PrefetchPair>();
-
- for(Iterator<PrefetchPair> it1=ppairs.iterator();it1.hasNext();) {
- PrefetchPair pp1=it1.next();
- if (toremove.contains(pp1))
- continue;
- int l1=pp1.desc.size()+1;
- for(Iterator<PrefetchPair> it2=ppairs.iterator();it2.hasNext();) {
- PrefetchPair pp2=it2.next();
- int l2=pp2.desc.size()+1;
-
- if (l1<l2&&isSubSet(pp1,pp2))
- toremove.add(pp1);
- else
- if (l2>l1&&isSubSet(pp2,pp1))
- toremove.add(pp2);
- }
- }
-
- ppairs.removeAll(toremove);
- }
- }
-
- /** This function returns: true if the shorter prefetch pair is a subset of the longer prefetch
- * pair else it returns: false */
- private boolean isSubSet(PrefetchPair shrt, PrefetchPair lng) {
- if (shrt.base != lng.base) {
- return false;
- }
- for (int j = 0; j < shrt.desc.size(); j++) {
- if(shrt.getDescAt(j) instanceof IndexDescriptor) {
- IndexDescriptor shrtid = (IndexDescriptor) shrt.getDescAt(j);
- if(lng.getDescAt(j) instanceof IndexDescriptor){
- IndexDescriptor lngid = (IndexDescriptor) lng.getDescAt(j);
- if(shrtid.equals(lngid)) {
- continue;
- } else {
- return false;
- }
- } else {
- return false;
- }
- } else {
- if ((Descriptor)shrt.getDescAt(j) != (Descriptor)lng.getDescAt(j)){
- return false;
- }
- }
- }
- return true;
- }
-
- /**This function compares all the prefetch pairs in a Prefetch set hashtable and
- * returns: true if something has changed in the new Prefetch set else
- * returns: false
- */
- private boolean comparePSet1(HashSet<PrefetchPair> oldPSet, HashSet<PrefetchPair>newPSet) {
- if(oldPSet.size() != newPSet.size()) {
- return true;
- } else {
- for(Iterator it = newPSet.iterator();it.hasNext();) {
- if(!oldPSet.contains((PrefetchPair)it.next())) {
- return true;
- }
- }
- }
- return false;
- }
-
- /** This function creates a set called pset1 that contains prefetch pairs that have already
- * been prefetched. While traversing the graph of a flat representation in a top down fashion,
- * this function creates pset1 such that it contains prefetch pairs that have been prefetched at
- * the previous nodes */
-
- private void applyPrefetchInsertRules(FlatNode fn, LinkedList<FlatNode> newvisited, Hashtable<FlatNode, HashSet<PrefetchPair>> pset1_hash, Hashtable<FlatNode, HashSet<PrefetchPair>> newprefetchset) {
- if(fn.kind() == FKind.FlatMethod) {
- HashSet<PrefetchPair> pset1 = new HashSet<PrefetchPair>();
- Hashtable<PrefetchPair, Double> prefetchset = prefetch_hash.get(fn);
- for(Enumeration e = prefetchset.keys();e.hasMoreElements();) {
- PrefetchPair pp = (PrefetchPair) e.nextElement();
- /* Apply initial rule */
- if(prefetchset.get(pp).doubleValue() >= PREFETCH_THRESHOLD_PROB) {
- pset1.add(pp);
- }
- }
- /* Enqueue child node if Pset1 has changed */
- if (comparePSet1(pset1_hash.get(fn), pset1)) {
- for(int j=0; j<fn.numNext(); j++) {
- FlatNode nn = fn.getNext(j);
- newvisited.addLast((FlatNode)nn);
- }
- pset1_hash.put(fn, pset1);
- }
- newprefetchset.put(fn, pset1);
- } else { /* Nodes other than Flat Method Node */
- HashSet<PrefetchPair> pset2 = new HashSet<PrefetchPair>();
- HashSet<PrefetchPair> newpset = new HashSet<PrefetchPair>();
- Hashtable<PrefetchPair, Double> prefetchset = prefetch_hash.get(fn);
- Hashtable<FlatNode, PairMap> ppairmaphash = pmap_hash.get(fn);
- for(Enumeration epset = prefetchset.keys(); epset.hasMoreElements();) {
- PrefetchPair pp = (PrefetchPair) epset.nextElement();
- boolean pprobIsGreater = (prefetchset.get(pp).doubleValue() >= PREFETCH_THRESHOLD_PROB);
- boolean mapprobIsLess=false;
- boolean mapIsPresent=true;
- for(int i=0;i<fn.numPrev();i++) {
- FlatNode parentnode=fn.getPrev(i);
- PairMap pm = (PairMap) ppairmaphash.get(parentnode);
- //Find if probability is less for previous node
- if(pm!=null&&pm.getPair(pp) != null) {
- PrefetchPair mappedpp = pm.getPair(pp);
- if(prefetch_hash.get(parentnode).containsKey(mappedpp)) {
- double prob = prefetch_hash.get(parentnode).get(mappedpp).doubleValue();
- if(prob < PREFETCH_THRESHOLD_PROB)
- mapprobIsLess = true;
- } else
- mapprobIsLess = true;
- } else {
- mapprobIsLess = true;
- }
- /* Build pset2 */
- if(pm !=null) {
- HashSet pset = pset1_hash.get(parentnode);
- if(pset.isEmpty()||!pset.contains((PrefetchPair) pm.getPair(pp)))
- mapIsPresent = false;
- } else
- mapIsPresent=false;
- }
-
- if(mapIsPresent)
- pset2.add(pp);
-
- if(pprobIsGreater && mapprobIsLess)
- newpset.add(pp);
- }
-
- HashSet<PrefetchPair> pset1 = new HashSet<PrefetchPair>();
- pset1.addAll(pset2);
- pset1.addAll(newpset);
- /* Enqueue child node if Pset1 has changed */
- if (comparePSet1(pset1_hash.get(fn), pset1)) {
- for(int i=0; i<fn.numNext(); i++) {
- FlatNode nn = fn.getNext(i);
- newvisited.addLast((FlatNode)nn);
- }
- pset1_hash.put(fn, pset1);
- }
-
- /* To insert prefetch, apply rule: if the newpset minus pset2 is nonempty
- * then insert a new prefetch node here*/
-
- HashSet<PrefetchPair> s = new HashSet<PrefetchPair>();
- s.addAll(newpset);
- s.removeAll(pset2);
- newprefetchset.put(fn, s);
- }
- }
-
- private void addFlatPrefetchNode(Hashtable<FlatNode, HashSet<PrefetchPair>> newprefetchset) {
- boolean isFNPresent = false; /* Detects presence of FlatNew node */
- /* This modifies the Flat representation graph */
- for(Enumeration e = newprefetchset.keys();e.hasMoreElements();) {
- FlatNode fn = (FlatNode) e.nextElement();
- FlatPrefetchNode fpn = new FlatPrefetchNode();
- if(newprefetchset.get(fn).size() > 0) {
- fpn.insAllpp((HashSet)newprefetchset.get(fn));
- if(fn.kind() == FKind.FlatMethod) {
- FlatNode nn = fn.getNext(0);
- fn.setNext(0, fpn);
- fpn.addNext(nn);
- fpn.siteid = prefetchsiteid++;
- } else {
- /* Check if previous node of this FlatNode is a NEW node
- * If yes, delete this flatnode and its prefetch set from hash table
- * This eliminates prefetches for NULL ptrs*/
- for(int i = 0; i< fn.numPrev(); i++) {
- FlatNode nn = fn.getPrev(i);
- if(nn.kind() == FKind.FlatNew) {
- isFNPresent = true;
+ } else if(childpp.base == currfen.getDst() && (childpp.getDesc() == null)) {
+ child_prefetch_set_copy.remove(childpp);
+ } else if(childpp.containsTemp(currfen.getDst())) {
+ child_prefetch_set_copy.remove(childpp);
+ } else {
+ continue;
+ }
+ }
+ /* Check if curr prefetch set and the child prefetch set have same prefetch pairs
+ * if so calculate the new probability */
+ for(Enumeration ecld = child_prefetch_set_copy.keys(); ecld.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
+ for(Enumeration e = currcopy.keys(); e.hasMoreElements(); ) {
+ currpp = (PrefetchPair) e.nextElement();
+ if(currpp.equals(childpp)) {
+ pm.addPair(childpp, currpp);
+ child_prefetch_set_copy.remove(childpp);
+ break;
+ }
+ }
+ }
+
+ /* Merge child prefetch pairs */
+ for (Enumeration ecld = child_prefetch_set_copy.keys(); ecld.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
+ tocompare.put(childpp, child_prefetch_set_copy.get(childpp).doubleValue());
+ pm.addPair(childpp, childpp);
+ child_prefetch_set_copy.remove(childpp);
+ }
+
+ /* Merge curr prefetch pairs */
+ for (Enumeration e = currcopy.keys(); e.hasMoreElements(); ) {
+ currpp = (PrefetchPair) e.nextElement();
+ tocompare.put(currpp, currcopy.get(currpp).doubleValue());
+ currcopy.remove(currpp);
+ }
+
+ updatePairMap(curr, pm, 0);
+ updatePrefetchSet(curr, tocompare);
+ }
+
+ /** This function processes the prefetch set of a FlatSetFieldNode
+ * It generates a new prefetch set after comparision with its children
+ * It compares the old prefetch set with this new prefetch set and enqueues the parents
+ * of the current node if change occurs and then updates the global flatnode hash table
+ * */
+ private void processFlatSetFieldNode(FlatNode curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
+ Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
+ FlatSetFieldNode currfsfn = (FlatSetFieldNode) curr;
+ PairMap pm = new PairMap();
+
+ for (Enumeration ecld = child_prefetch_set_copy.keys(); ecld.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
+ if(childpp.base == currfsfn.getDst()) {
+ int size = childpp.desc.size();
+ if(size >=2) { /*e.g. x.f = g (with child prefetches x.f.g, x.f[0].j) */
+ if((childpp.getDescAt(0) instanceof FieldDescriptor) && (childpp.getDescAt(0) == currfsfn.getField())) {
+ ArrayList<Descriptor> newdesc = new ArrayList<Descriptor>();
+ for(int i = 0; i<(childpp.desc.size()-1); i++) {
+ newdesc.add(i,childpp.desc.get(i+1));
+ }
+ PrefetchPair newpp = new PrefetchPair(currfsfn.getSrc(), newdesc);
+ Double newprob = child_prefetch_set_copy.get(childpp).doubleValue();
+ tocompare.put(newpp, newprob);
+ pm.addPair(childpp, newpp);
+ child_prefetch_set_copy.remove(childpp);
+ /* Check for independence of prefetch pairs in newly generated prefetch pair
+ * to compute new probability */
+ if(child_prefetch_set_copy.containsKey(newpp)) {
+ newprob = (1.0 - ((1.0 - child_prefetch_set_copy.get(newpp).doubleValue()) * (1.0 - tocompare.get(newpp).doubleValue())));
+ if(newprob < ANALYSIS_THRESHOLD_PROB) {
+ tocompare.remove(newpp);
+ } else {
+ tocompare.put(newpp, newprob);
+ pm.addPair(newpp, newpp);
}
+ child_prefetch_set_copy.remove(newpp);
}
- if(!isFNPresent) {
- while(fn.numPrev() > 0) {
- FlatNode nn = fn.getPrev(0);
- for(int j = 0; j<nn.numNext(); j++) {
- if(nn.getNext(j) == fn) {
- nn.setNext(j, fpn);
- }
+ }
+ } else if(size==1) { /* e.g x.f = g (with child prefetch x.f) */
+ if((childpp.getDescAt(0) instanceof FieldDescriptor) && (childpp.getDescAt(0) == currfsfn.getField())) {
+ child_prefetch_set_copy.remove(childpp);
+ }
+ } else {
+ continue;
+ }
+ }
+ }
+
+ /* Merge child prefetch pairs */
+ for (Enumeration ecld = child_prefetch_set_copy.keys(); ecld.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
+ tocompare.put(childpp, child_prefetch_set_copy.get(childpp).doubleValue());
+ pm.addPair(childpp, childpp);
+ child_prefetch_set_copy.remove(childpp);
+ }
+
+ updatePairMap(curr, pm, 0);
+ updatePrefetchSet(curr, tocompare);
+ }
+
+ /** This function processes the prefetch set of a FlatSetElementNode
+ * It generates a new prefetch set after comparision with its children
+ * It compares the old prefetch set with this new prefetch set and enqueues the parents
+ * of the current node if change occurs and then updates the global flatnode hash table
+ * */
+ private void processFlatSetElementNode(FlatNode curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
+ Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
+ FlatSetElementNode currfsen = (FlatSetElementNode) curr;
+ PairMap pm = new PairMap();
+
+ for (Enumeration ecld = child_prefetch_set_copy.keys(); ecld.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
+ if (childpp.base == currfsen.getDst()) {
+ int sizedesc = childpp.desc.size();
+ if((childpp.getDescAt(0) instanceof IndexDescriptor)) {
+ int sizetempdesc = ((IndexDescriptor)(childpp.getDescAt(0))).tddesc.size();
+ if(sizetempdesc == 1) {
+ if((((IndexDescriptor)childpp.getDescAt(0)).tddesc.get(0) == currfsen.getIndex()) && (sizedesc>=2)) {
+ /* For e.g. a[i] = g with child prefetch set a[i].r or a[i].r.f */
+ ArrayList<Descriptor> newdesc = new ArrayList<Descriptor>();
+ for(int i = 0; i<(childpp.desc.size()-1); i++) {
+ newdesc.add(i,childpp.desc.get(i+1));
+ }
+ PrefetchPair newpp = new PrefetchPair(currfsen.getSrc(), newdesc);
+ Double newprob = child_prefetch_set_copy.get(childpp).doubleValue();
+ tocompare.put(newpp, newprob);
+ pm.addPair(childpp, newpp);
+ child_prefetch_set_copy.remove(childpp);
+ /* Check for independence of prefetch pairs to compute new probability */
+ if(child_prefetch_set_copy.containsKey(newpp)) {
+ newprob = (1.0 - ((1.0 - child_prefetch_set_copy.get(newpp).doubleValue()) * (1.0 - tocompare.get(newpp).doubleValue())));
+ if(newprob < ANALYSIS_THRESHOLD_PROB) {
+ tocompare.remove(newpp);
+ } else {
+ tocompare.put(newpp, newprob);
+ pm.addPair(newpp, newpp);
}
+ child_prefetch_set_copy.remove(newpp);
}
- fpn.addNext(fn);
- fpn.siteid = prefetchsiteid++;
+ } else if((((IndexDescriptor)childpp.getDescAt(0)).tddesc.get(0) == currfsen.getIndex()) && (sizedesc==1))
+ /* For e.g. a[i] = g with child prefetch set a[i] */
+ child_prefetch_set_copy.remove(childpp);
+ } else {
+ continue;
+ }
+ }
+ }
+ }
+ /* Merge child prefetch pairs */
+ for (Enumeration ecld = child_prefetch_set_copy.keys(); ecld.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
+ tocompare.put(childpp, child_prefetch_set_copy.get(childpp).doubleValue());
+ pm.addPair(childpp, childpp);
+ child_prefetch_set_copy.remove(childpp);
+ }
+
+ updatePairMap(curr, pm, 0);
+ updatePrefetchSet(curr, tocompare);
+ }
+
+ /** This function applies rules and does analysis for a FlatOpNode
+ * And updates the global prefetch hashtable
+ * */
+ private void processFlatOpNode(FlatNode curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
+ int index;
+ Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
+ FlatOpNode currfopn = (FlatOpNode) curr;
+ PairMap pm = new PairMap();
+
+ if(currfopn.getOp().getOp() == Operation.ASSIGN) {
+ for (Enumeration ecld = child_prefetch_set_copy.keys(); ecld.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
+ PrefetchPair copyofchildpp = (PrefetchPair) childpp.clone();
+
+ /* For cases like x=y with child prefetch set x[i].z,x.g*/
+ if(childpp.base == currfopn.getDest()) {
+ ArrayList<Descriptor> newdesc = new ArrayList<Descriptor>();
+ newdesc.addAll(childpp.desc);
+ PrefetchPair newpp = new PrefetchPair(currfopn.getLeft(), newdesc);
+ Double newprob = child_prefetch_set_copy.get(childpp).doubleValue();
+ tocompare.put(newpp, newprob);
+ pm.addPair(childpp, newpp);
+ child_prefetch_set_copy.remove(childpp);
+ /* Check for independence of prefetch pairs to compute new probability */
+ if(child_prefetch_set_copy.containsKey(newpp)) {
+ newprob = (1.0 - ((1.0 - child_prefetch_set_copy.get(newpp).doubleValue()) * (1.0 - tocompare.get(newpp).doubleValue())));
+ if(newprob < ANALYSIS_THRESHOLD_PROB) {
+ tocompare.remove(newpp);
+ } else {
+ tocompare.put(newpp, newprob);
+ pm.addPair(newpp, newpp);
}
- } //end of else
- } //End of if
- } //end of for
+ child_prefetch_set_copy.remove(newpp);
+ }
+ /* For cases like x=y with child prefetch set r[x].p, r[p+x].q where x is a tempdescriptor*/
+ } else if(copyofchildpp.containsTemp(currfopn.getDest())) {
+ PrefetchPair newpp=copyofchildpp.replaceTemp(currfopn.getDest(), new TempDescriptor[] {currfopn.getLeft()});
+ Double newprob = child_prefetch_set_copy.get(childpp).doubleValue();
+ tocompare.put(newpp, newprob);
+ pm.addPair(childpp, newpp);
+ child_prefetch_set_copy.remove(childpp);
+ /* Check for independence of prefetch pairs to compute new probability*/
+ if(child_prefetch_set_copy.containsKey(newpp)) {
+ newprob = (1.0 - ((1.0 - child_prefetch_set_copy.get(newpp).doubleValue()) * (1.0 - tocompare.get(newpp).doubleValue())));
+ if(newprob < ANALYSIS_THRESHOLD_PROB) {
+ tocompare.remove(newpp);
+ } else {
+ tocompare.put(newpp, newprob);
+ pm.addPair(newpp, newpp);
+ }
+ child_prefetch_set_copy.remove(newpp);
+ }
+ newpp = null;
+ } else {
+ continue;
+ }
+ }
+ //case i = i+z with child prefetch set a[i].x
+ } else if(currfopn.getRight()!=null && (currfopn.getOp().getOp() == Operation.ADD)) {
+ for (Enumeration ecld = child_prefetch_set_copy.keys(); ecld.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
+ PrefetchPair copyofchildpp = (PrefetchPair) childpp.clone();
+
+ if(copyofchildpp.containsTemp(currfopn.getDest())) {
+ PrefetchPair newpp=copyofchildpp.replaceTemp(currfopn.getDest(), new TempDescriptor[] {currfopn.getLeft(), currfopn.getRight()});
+ Double newprob = child_prefetch_set_copy.get(childpp).doubleValue();
+ tocompare.put(newpp, newprob);
+ pm.addPair(childpp, newpp);
+ child_prefetch_set_copy.remove(childpp);
+ /* Check for independence of prefetch pairs to compute new probability*/
+ if(child_prefetch_set_copy.containsKey(newpp)) {
+ newprob = (1.0 - ((1.0 - child_prefetch_set_copy.get(newpp).doubleValue()) * (1.0 - tocompare.get(newpp).doubleValue())));
+ if(newprob < ANALYSIS_THRESHOLD_PROB) {
+ tocompare.remove(newpp);
+ } else {
+ tocompare.put(newpp, newprob);
+ pm.addPair(newpp, newpp);
+ }
+ child_prefetch_set_copy.remove(newpp);
+ }
+ } else {
+ continue;
+ }
+ }
+ } else if(currfopn.getRight()!=null && (currfopn.getOp().getOp() == Operation.SUB)) {
+ for(Enumeration ecld = child_prefetch_set_copy.keys(); ecld.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
+ if(childpp.containsTemp(currfopn.getDest())) {
+ child_prefetch_set_copy.remove(childpp);
+ }
+ }
+ } else {
+ //FIXME Is not taken care of for cases like x = -y followed by a[x].i
+ }
+
+ /* Merge child prefetch pairs */
+ for (Enumeration ecld = child_prefetch_set_copy.keys(); ecld.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
+ tocompare.put(childpp, child_prefetch_set_copy.get(childpp).doubleValue());
+ pm.addPair(childpp, childpp);
+ child_prefetch_set_copy.remove(childpp);
+ }
+
+ updatePairMap(curr, pm, 0);
+ updatePrefetchSet(curr, tocompare);
+ }
+
+ /** This function processes a FlatLiteralNode where cases such as
+ * for e.g. i = 0 with child prefetch sets a[i].r, a[j+i].r or a[j].b[i].r
+ * are handled */
+ private void processFlatLiteralNode(FlatNode curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
+ Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
+ FlatLiteralNode currfln = (FlatLiteralNode) curr;
+ PairMap pm = new PairMap();
+
+ if(currfln.getType().isIntegerType()) {
+ for (Enumeration ecld = child_prefetch_set_copy.keys(); ecld.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
+ PrefetchPair copyofchildpp = (PrefetchPair) childpp.clone();
+ if(copyofchildpp.containsTemp(currfln.getDst())) {
+ ArrayList<Descriptor> copychilddesc = (ArrayList<Descriptor>)copyofchildpp.getDesc();
+ int sizetempdesc = copychilddesc.size();
+ for(ListIterator it = copychilddesc.listIterator(); it.hasNext(); ) {
+ Object o = it.next();
+ if(o instanceof IndexDescriptor) {
+ ArrayList<TempDescriptor> td = (ArrayList<TempDescriptor>)((IndexDescriptor)o).tddesc;
+ int sizetddesc = td.size();
+ if(td.contains(currfln.getDst())) {
+ int index = td.indexOf(currfln.getDst());
+ td.remove(index);
+ ((IndexDescriptor)o).offset += (Integer)currfln.getValue();
+ }
+ }
+ }
+ ArrayList<Descriptor> newdesc = new ArrayList<Descriptor>();
+ newdesc.addAll(copychilddesc);
+ PrefetchPair newpp = new PrefetchPair(childpp.base, newdesc);
+ Double newprob = (child_prefetch_set_copy.get(childpp)).doubleValue();
+ tocompare.put(newpp, newprob);
+ pm.addPair(childpp, newpp);
+ child_prefetch_set_copy.remove(childpp);
+ /* Check for independence of prefetch pairs to compute new probability */
+ if(child_prefetch_set_copy.containsKey(newpp)) {
+ newprob = (1.0 - ((1.0 - child_prefetch_set_copy.get(newpp).doubleValue()) * (1.0 - tocompare.get(newpp).doubleValue())));
+ if(newprob < ANALYSIS_THRESHOLD_PROB) {
+ tocompare.remove(newpp);
+ } else {
+ tocompare.put(newpp, newprob);
+ pm.addPair(newpp, newpp);
+ }
+ child_prefetch_set_copy.remove(newpp);
+ }
+ }
+ }
+ }
+
+ /* Merge child prefetch pairs */
+ for (Enumeration ecld = child_prefetch_set_copy.keys(); ecld.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
+ tocompare.put(childpp, child_prefetch_set_copy.get(childpp).doubleValue());
+ pm.addPair(childpp, childpp);
+ child_prefetch_set_copy.remove(childpp);
+ }
+
+ updatePairMap(curr, pm, 0);
+ updatePrefetchSet(curr, tocompare);
+ }
+
+ /** This function processes a FlatMethod where the method propagates
+ * the entire prefetch set of its child node */
+ private void processFlatMethod(FlatNode curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
+ Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
+ FlatMethod currfm = (FlatMethod) curr;
+ PairMap pm = new PairMap();
+
+ /* Merge child prefetch pairs */
+ for (Enumeration ecld = child_prefetch_set_copy.keys(); ecld.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) ecld.nextElement();
+ tocompare.put(childpp, child_prefetch_set_copy.get(childpp).doubleValue());
+ pm.addPair(childpp, childpp);
+ }
+
+ updatePairMap(curr, pm, 0);
+ updatePrefetchSet(curr, tocompare);
+ }
+
+ /** This function handles the processes the FlatNode of type FlatCondBranch
+ * It combines prefetches of both child elements and create a new hash table called
+ * branch_prefetch_set to contains the entries of both its children
+ */
+ private void processFlatCondBranch(FlatCondBranch fcb, MethodDescriptor md) {
+ Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>(); //temporary hash table
+ PairMap truepm = new PairMap();
+ PairMap falsepm = new PairMap();
+ Hashtable<PrefetchPair, Double> truechild=prefetch_hash.get(fcb.getNext(0));
+ Hashtable<PrefetchPair, Double> falsechild=prefetch_hash.get(fcb.getNext(1));
+
+ HashSet<PrefetchPair> allpp=new HashSet<PrefetchPair>();
+ allpp.addAll(truechild.keySet());
+ allpp.addAll(falsechild.keySet());
+
+ for(Iterator<PrefetchPair> ppit=allpp.iterator(); ppit.hasNext(); ) {
+ PrefetchPair pp=ppit.next();
+ double trueprob=0,falseprob=0;
+ if (truechild.containsKey(pp))
+ trueprob=truechild.get(pp).doubleValue();
+ if (falsechild.containsKey(pp))
+ falseprob=falsechild.get(pp).doubleValue();
+
+ double newprob=trueprob*fcb.getTrueProb()+falseprob*fcb.getFalseProb();
+ if (loop.isLoopingBranch(md,fcb)&&
+ newprob<falseprob) {
+ newprob=falseprob;
+ }
+
+ if(newprob < ANALYSIS_THRESHOLD_PROB) //Skip pp that are below threshold
+ continue;
+
+ tocompare.put(pp, newprob);
+ if (truechild.containsKey(pp))
+ truepm.addPair(pp, pp);
+
+ if (falsechild.containsKey(pp))
+ falsepm.addPair(pp, pp);
+
+ }
+
+ updatePairMap(fcb, truepm, 0);
+ updatePairMap(fcb, falsepm, 1);
+ updatePrefetchSet(fcb, tocompare);
+ }
+
+ /** If FlatNode is not concerned with the prefetch set of its Child then propagate
+ * prefetches up the FlatNode*/
+ private void processDefaultCase(FlatNode curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
+ PairMap pm = new PairMap();
+ Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
+
+ /* Propagate all child nodes */
+nexttemp:
+ for(Enumeration e = child_prefetch_set_copy.keys(); e.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) e.nextElement();
+ TempDescriptor[] writearray=curr.writesTemps();
+ for(int i=0; i<writearray.length; i++) {
+ TempDescriptor wtd=writearray[i];
+ if(childpp.base == wtd||
+ childpp.containsTemp(wtd))
+ continue nexttemp;
+ }
+ tocompare.put(childpp, child_prefetch_set_copy.get(childpp));
+ pm.addPair(childpp, childpp);
+ }
+
+ updatePairMap(curr, pm, 0);
+ updatePrefetchSet(curr, tocompare);
+ }
+
+ /** If FlatNode is not concerned with the prefetch set of its Child then propagate
+ * prefetches up the FlatNode*/
+ private void processCall(FlatCall curr, Hashtable<PrefetchPair, Double> child_prefetch_set_copy) {
+ PairMap pm = new PairMap();
+ Hashtable<PrefetchPair, Double> tocompare = new Hashtable<PrefetchPair, Double>();
+
+ /* Don't propagate prefetches across cache clear */
+ if (!(curr.getMethod().getClassMethodName().equals("System.clearPrefetchCache")||
+ curr.getMethod().getClassMethodName().equals("Barrier.enterBarrier"))) {
+ /* Propagate all child nodes */
+nexttemp:
+ for(Enumeration e = child_prefetch_set_copy.keys(); e.hasMoreElements(); ) {
+ PrefetchPair childpp = (PrefetchPair) e.nextElement();
+ TempDescriptor[] writearray=curr.writesTemps();
+ for(int i=0; i<writearray.length; i++) {
+ TempDescriptor wtd=writearray[i];
+ if(childpp.base == wtd||
+ childpp.containsTemp(wtd))
+ continue nexttemp;
+ }
+ tocompare.put(childpp, child_prefetch_set_copy.get(childpp));
+ pm.addPair(childpp, childpp);
+ }
+
}
+ updatePairMap(curr, pm, 0);
+ updatePrefetchSet(curr, tocompare);
+ }
+
+ /** This function prints the Prefetch pairs of a given flatnode */
+ private void printPrefetchPairs(FlatNode fn) {
+ System.out.println(fn);
+ if(prefetch_hash.containsKey(fn)) {
+ System.out.print("Prefetch" + "(");
+ Hashtable<PrefetchPair, Double> currhash = (Hashtable) prefetch_hash.get(fn);
+ for(Enumeration pphash= currhash.keys(); pphash.hasMoreElements(); ) {
+ PrefetchPair pp = (PrefetchPair) pphash.nextElement();
+ double v=currhash.get(pp).doubleValue();
+ if (v>.2)
+ System.out.print(pp.toString() +"-"+v + ", ");
+ }
+ System.out.println(")");
+ } else {
+ System.out.println("Flatnode is currently not present in the global hash: Prefetch Set is Empty");
+ }
+ }
+
+ private void doInsPrefetchAnalysis(FlatMethod fm, Hashtable<FlatNode, HashSet<PrefetchPair>> newprefetchset) {
+ Hashtable<FlatNode, HashSet<PrefetchPair>> pset1_hash = new Hashtable<FlatNode, HashSet<PrefetchPair>>();
+
+ Set visitset=fm.getNodeSet();
+ while(!visitset.isEmpty()) {
+ FlatNode fn = (FlatNode) visitset.iterator().next();
+ visitset.remove(fn);
+ pset1_hash.put(fn, new HashSet<PrefetchPair>());
+ }
+
+ Set tovisit=fm.getNodeSet();
+ /* Start with a top down sorted order of nodes */
+ while(!tovisit.isEmpty()) {
+ FlatNode fn=(FlatNode)tovisit.iterator().next();
+ tovisit.remove(fn);
+ applyPrefetchInsertRules(fn, tovisit, pset1_hash, newprefetchset);
+ }
+ delSubsetPPairs(newprefetchset);
+ }
+
+ /** This function deletes the smaller prefetch pair subset from a list of prefetch pairs
+ * for e.g. if there are 2 prefetch pairs a.b.c.d and a.b.c for a given flatnode
+ * then this function drops a.b.c from the prefetch set of the flatnode */
+ private void delSubsetPPairs(Hashtable<FlatNode, HashSet<PrefetchPair>> newprefetchset) {
+ for (Enumeration e = newprefetchset.keys(); e.hasMoreElements(); ) {
+ FlatNode fn = (FlatNode) e.nextElement();
+ Set<PrefetchPair> ppairs = newprefetchset.get(fn);
+ Set<PrefetchPair> toremove=new HashSet<PrefetchPair>();
+
+ for(Iterator<PrefetchPair> it1=ppairs.iterator(); it1.hasNext(); ) {
+ PrefetchPair pp1=it1.next();
+ if (toremove.contains(pp1))
+ continue;
+ int l1=pp1.desc.size()+1;
+ for(Iterator<PrefetchPair> it2=ppairs.iterator(); it2.hasNext(); ) {
+ PrefetchPair pp2=it2.next();
+ int l2=pp2.desc.size()+1;
+
+ if (l1<l2&&isSubSet(pp1,pp2))
+ toremove.add(pp1);
+ else
+ if (l2>l1&&isSubSet(pp2,pp1))
+ toremove.add(pp2);
+ }
+ }
+
+ ppairs.removeAll(toremove);
+ }
+ }
+
+ /** This function returns: true if the shorter prefetch pair is a subset of the longer prefetch
+ * pair else it returns: false */
+ private boolean isSubSet(PrefetchPair shrt, PrefetchPair lng) {
+ if (shrt.base != lng.base) {
+ return false;
+ }
+ for (int j = 0; j < shrt.desc.size(); j++) {
+ if(shrt.getDescAt(j) instanceof IndexDescriptor) {
+ IndexDescriptor shrtid = (IndexDescriptor) shrt.getDescAt(j);
+ if(lng.getDescAt(j) instanceof IndexDescriptor) {
+ IndexDescriptor lngid = (IndexDescriptor) lng.getDescAt(j);
+ if(shrtid.equals(lngid)) {
+ continue;
+ } else {
+ return false;
+ }
+ } else {
+ return false;
+ }
+ } else {
+ if ((Descriptor)shrt.getDescAt(j) != (Descriptor)lng.getDescAt(j)) {
+ return false;
+ }
+ }
+ }
+ return true;
+ }
+
+ /**This function compares all the prefetch pairs in a Prefetch set hashtable and
+ * returns: true if something has changed in the new Prefetch set else
+ * returns: false
+ */
+ private boolean comparePSet1(HashSet<PrefetchPair> oldPSet, HashSet<PrefetchPair>newPSet) {
+ if(oldPSet.size() != newPSet.size()) {
+ return true;
+ } else {
+ for(Iterator it = newPSet.iterator(); it.hasNext(); ) {
+ if(!oldPSet.contains((PrefetchPair)it.next())) {
+ return true;
+ }
+ }
+ }
+ return false;
+ }
+
+ /** This function creates a set called pset1 that contains prefetch pairs that have already
+ * been prefetched. While traversing the graph of a flat representation in a top down fashion,
+ * this function creates pset1 such that it contains prefetch pairs that have been prefetched at
+ * the previous nodes */
+
+ private void applyPrefetchInsertRules(FlatNode fn, Set tovisit, Hashtable<FlatNode, HashSet<PrefetchPair>> pset1_hash, Hashtable<FlatNode, HashSet<PrefetchPair>> newprefetchset) {
+ if(fn.kind() == FKind.FlatMethod) {
+ HashSet<PrefetchPair> pset1 = new HashSet<PrefetchPair>();
+ Hashtable<PrefetchPair, Double> prefetchset = prefetch_hash.get(fn);
+ for(Enumeration e = prefetchset.keys(); e.hasMoreElements(); ) {
+ PrefetchPair pp = (PrefetchPair) e.nextElement();
+ /* Apply initial rule */
+ if(prefetchset.get(pp).doubleValue() >= PREFETCH_THRESHOLD_PROB) {
+ pset1.add(pp);
+ }
+ }
+ /* Enqueue child node if Pset1 has changed */
+ if (comparePSet1(pset1_hash.get(fn), pset1)) {
+ for(int j=0; j<fn.numNext(); j++) {
+ FlatNode nn = fn.getNext(j);
+ tovisit.add(nn);
+ }
+ pset1_hash.put(fn, pset1);
+ }
+ newprefetchset.put(fn, pset1);
+ } else { /* Nodes other than Flat Method Node */
+ HashSet<PrefetchPair> pset2 = new HashSet<PrefetchPair>();
+ HashSet<PrefetchPair> newpset = new HashSet<PrefetchPair>();
+ Hashtable<PrefetchPair, Double> prefetchset = prefetch_hash.get(fn);
+ Hashtable<FlatNode, PairMap> ppairmaphash = pmap_hash.get(fn);
+ for(Enumeration epset = prefetchset.keys(); epset.hasMoreElements(); ) {
+ PrefetchPair pp = (PrefetchPair) epset.nextElement();
+ boolean pprobIsGreater = (prefetchset.get(pp).doubleValue() >= PREFETCH_THRESHOLD_PROB);
+ boolean mapprobIsLess=false;
+ boolean mapIsPresent=true;
+ for(int i=0; i<fn.numPrev(); i++) {
+ FlatNode parentnode=fn.getPrev(i);
+ PairMap pm = (PairMap) ppairmaphash.get(parentnode);
+ //Find if probability is less for previous node
+ if(pm!=null&&pm.getPair(pp) != null) {
+ PrefetchPair mappedpp = pm.getPair(pp);
+ if(prefetch_hash.get(parentnode).containsKey(mappedpp)) {
+ double prob = prefetch_hash.get(parentnode).get(mappedpp).doubleValue();
+ if(prob < PREFETCH_THRESHOLD_PROB)
+ mapprobIsLess = true;
+ } else
+ mapprobIsLess = true;
+ } else {
+ mapprobIsLess = true;
+ }
+ /* Build pset2 */
+ if(pm !=null) {
+ HashSet pset = pset1_hash.get(parentnode);
+ if(!pset.contains((PrefetchPair) pm.getPair(pp)))
+ mapIsPresent = false;
+ } else
+ mapIsPresent=false;
+ }
+
+ if(mapIsPresent)
+ pset2.add(pp);
+
+ if(pprobIsGreater && mapprobIsLess)
+ newpset.add(pp);
+ }
+
+ HashSet<PrefetchPair> pset1 = new HashSet<PrefetchPair>();
+ pset1.addAll(pset2);
+ pset1.addAll(newpset);
+
+ /* Enqueue child node if Pset1 has changed */
+ if (comparePSet1(pset1_hash.get(fn), pset1)) {
+ for(int i=0; i<fn.numNext(); i++) {
+ FlatNode nn = fn.getNext(i);
+ tovisit.add(nn);
+ }
+ pset1_hash.put(fn, pset1);
+ }
+
+ /* To insert prefetch, apply rule: if the newpset minus pset2 is nonempty
+ * then insert a new prefetch node here*/
+
+ HashSet<PrefetchPair> s = new HashSet<PrefetchPair>();
+ s.addAll(newpset);
+ s.removeAll(pset2);
+ newprefetchset.put(fn, s);
+ }
+ }
+
+ private void addFlatPrefetchNode(Hashtable<FlatNode, HashSet<PrefetchPair>> newprefetchset) {
+ /* This modifies the Flat representation graph */
+ for(Enumeration e = newprefetchset.keys(); e.hasMoreElements(); ) {
+ FlatNode fn = (FlatNode) e.nextElement();
+ FlatPrefetchNode fpn = new FlatPrefetchNode();
+ if(newprefetchset.get(fn).size() > 0) {
+ fpn.insAllpp((HashSet)newprefetchset.get(fn));
+ if(fn.kind() == FKind.FlatMethod) {
+ FlatNode nn = fn.getNext(0);
+ fn.setNext(0, fpn);
+ fpn.addNext(nn);
+ fpn.siteid = prefetchsiteid++;
+ } else {
+ /* Check if previous node of this FlatNode is a NEW node
+ * If yes, delete this flatnode and its prefetch set from hash table
+ * This eliminates prefetches for NULL ptrs*/
+ while(fn.numPrev() > 0) {
+ FlatNode nn = fn.getPrev(0);
+ for(int j = 0; j<nn.numNext(); j++) {
+ if(nn.getNext(j) == fn) {
+ nn.setNext(j, fpn);
+ }
+ }
+ }
+ fpn.addNext(fn);
+ fpn.siteid = prefetchsiteid++;
+ } //end of else
+ } //End of if
+ } //end of for
+ }
}
projects / IRC.git / blobdiff