+++ /dev/null
-package Analysis.TaskStateAnalysis;
-import Analysis.TaskStateAnalysis.*;
-import IR.*;
-import IR.Tree.*;
-import IR.Flat.*;
-import java.util.*;
-import java.io.File;
-import java.io.FileWriter;
-
-public class TaskAnalysis {
- State state;
- Hashtable Adj_List;
- Hashtable flags;
- Hashtable extern_flags;
- Queue<TriggerState> q_main;
-
- /**
- * Class Constructor
- *
- * @param state a flattened State object
- * @see State
- */
- public TaskAnalysis(State state)
- {
- this.state=state;
- }
-
- /** This function returns the number of external flags, etc */
-
- private void getFlagsfromClasses() {
- flags=new Hashtable();
- extern_flags = new Hashtable();
-
- for(Iterator it_classes=state.getClassSymbolTable().getDescriptorsIterator();it_classes.hasNext();) {
-
- ClassDescriptor cd = (ClassDescriptor)it_classes.next();
- System.out.println(cd.getSymbol());
- Vector vFlags=new Vector();
- FlagDescriptor flag[];
- int ctr=0;
-
-
- /* Adding the flags of the super class */
- if (cd.getSuper()!=null) {
- ClassDescriptor superdesc=cd.getSuperDesc();
-
- for(Iterator it_cflags=superdesc.getFlags();it_cflags.hasNext();) {
- FlagDescriptor fd = (FlagDescriptor)it_cflags.next();
- System.out.println(fd.toString());
- vFlags.add(fd);
- }
- }
-
- for(Iterator it_cflags=cd.getFlags();it_cflags.hasNext();) {
- FlagDescriptor fd = (FlagDescriptor)it_cflags.next();
- System.out.println(fd.toString());
- vFlags.add(fd);
- }
-
- if (vFlags.size()!=0) {
- flag=new FlagDescriptor[vFlags.size()];
-
- for(int i=0;i < vFlags.size() ; i++) {
- if (((FlagDescriptor)vFlags.get(i)).getExternal()) {
- flag[ctr]=(FlagDescriptor)vFlags.get(i);
- vFlags.remove(flag[ctr]);
- ctr++;
- }
- }
- for(int i=0;i < vFlags.size() ; i++) {
- flag[i+ctr]=(FlagDescriptor)vFlags.get(i);
- }
- extern_flags.put(cd,new Integer(ctr));
- flags.put(cd,flag);
-
- }
- }
- }
-
- public void taskAnalysis() throws java.io.IOException {
- Adj_List=new Hashtable();
-
- getFlagsfromClasses();
-
- int externs;
- q_main=new LinkedList<TriggerState>();
-
- for(Iterator it_classes=(Iterator)flags.keys();it_classes.hasNext();) {
- ClassDescriptor cd=(ClassDescriptor)it_classes.next();
-
- externs=((Integer)extern_flags.get(cd)).intValue();
-
- FlagDescriptor[] fd=(FlagDescriptor[])flags.get(cd);
- //Debug block
- System.out.println("Inside taskAnalysis;\n Class:"+ cd.getSymbol());
- System.out.println("No of externs " + externs);
- System.out.println("No of flags: "+fd.length);
- //Debug block
- if (fd.length == externs) {
- System.out.println("extern called");
- boolean onlyExterns=true;
- } else {
- if ((fd.length == 1)
- && (fd[0].getSymbol().compareTo("initialstate")==0)) {
- FlagState fstemp=new FlagState(fd, cd);
- Hashtable Adj_List_temp=new Hashtable();
-
- fstemp.put(fd[0],new Boolean(true));
- Vector vtemp=new Vector();
- vtemp.add(new Edge(fstemp,"Runtime"));
- Adj_List_temp.put(new FlagState(fd,cd),vtemp);
- Adj_List.put(cd,Adj_List_temp);
-
- Queue<TriggerState> q_temp=analyseTasks(new TriggerState(cd,fstemp));
-
-
- if ( q_temp != null) {
- q_main.addAll(q_temp);
- }
-
- }
- }
- }
- while (q_main.size() > 0) {
- // ****debug block********
- for (Iterator it_qm=q_main.iterator();it_qm.hasNext();)
- {
- TriggerState ts_qm=(TriggerState)it_qm.next();
- FlagState fs_qm=ts_qm.getState();
- System.out.println("/***********contents of main q**********/");
- System.out.println("FS : "+fs_qm.toString((FlagDescriptor [])flags.get(ts_qm.getClassDescriptor())));
-
-
- }
- System.out.println("/*********************************/");
- // ****debug block********
- Queue<TriggerState> q_temp=analyseTasks(q_main.poll());
- if ( q_temp != null) {
- q_main.addAll(q_temp);
- }
- }
-
- //Creating DOT files
- Enumeration e=Adj_List.keys();
-
- while (e.hasMoreElements()) {
- System.out.println("creating dot file");
- ClassDescriptor cdtemp=(ClassDescriptor)e.nextElement();
- System.out.println((cdtemp.getSymbol()));
- createDOTfile(cdtemp);
- }
-
- }
-
-
- public Queue<TriggerState> analyseTasks(TriggerState ts) throws java.io.IOException {
- Queue<FlagState> q;
- Queue<FlagState> qft;
-
- Hashtable Adj_List_temp;
- Queue<TriggerState> q_retval;
-
- ClassDescriptor cd=ts.getClassDescriptor();
-
- if (Adj_List.containsKey(cd)) {
- //Debug block
- System.out.println("Inside analyseTasks;\n Checking if adj_list contains the class desc:"+ cd.getSymbol());
- //Debug block
-
- Adj_List_temp=(Hashtable)Adj_List.get(cd);
- } else {
- Adj_List_temp=new Hashtable();
- Adj_List.put(cd,Adj_List_temp);
- }
-
-
- int externs=((Integer)extern_flags.get(cd)).intValue();
- FlagDescriptor[] fd=(FlagDescriptor[])flags.get(cd);
-
- q = new LinkedList<FlagState>();
- q_retval=new LinkedList<TriggerState>();
- q.offer(ts.getState());
-
- //***Debug Block***
-
- while (q.size() != 0) {
- System.out.println("inside while loop in analysetasks \n");
-
- FlagState fsworking=q.poll();
-
- //***Debug Block***
- FlagDescriptor[] ftemp=(FlagDescriptor[])flags.get(cd);
- System.out.println("Processing state: "+cd.getSymbol()+" " + fsworking.toString(ftemp));
-
- //***Debug Block***
-
-
- for(Iterator it_tasks=state.getTaskSymbolTable().getDescriptorsIterator();it_tasks.hasNext();) {
- TaskDescriptor td = (TaskDescriptor)it_tasks.next();
- boolean taskistriggered=false;
- int ctr=0;
- String taskname=getTaskName(td);
-
-
-
- //***Debug Block***
-
- System.out.println();
- System.out.println("Method: AnalyseTasks");
- System.out.println(taskname);
- System.out.println();
-
- //***Debug Block***
-
-
- for(int i=0; i < td.numParameters(); i++) {
- FlagExpressionNode fen=td.getFlag(td.getParameter(i));
- if (isTaskTrigger(fen,fsworking))
- taskistriggered = true;
- }
-
- if (taskistriggered) {
- //***Debug Block***
- //
- System.out.println("inside taskistriggered");
-
- //***Debug Block***
- if (wasFlagStateProcessed(Adj_List_temp,fsworking)) {
- if (! (fd.length == externs))
- continue;
- } else
- Adj_List_temp.put(fsworking,new Vector());
-
- FlatMethod fm = state.getMethodFlat(td);
- FlatNode fn=fm.methodEntryNode();
-
- HashSet tovisit= new HashSet();
- HashSet visited= new HashSet();
-
- tovisit.add(fn);
- while(!tovisit.isEmpty()) {
- FlatNode fn1 = (FlatNode)tovisit.iterator().next();
- tovisit.remove(fn1);
- visited.add(fn1);
- for(int i = 0; i < fn1.numNext(); i++) {
- FlatNode nn=fn1.getNext(i);
- if (nn.kind()==13) {
- //***Debug Block***
- if (((FlatFlagActionNode)nn).getFFANType() == FlatFlagActionNode.PRE) {
- throw new Error("PRE FlagActions not supported");
- } else if (((FlatFlagActionNode)nn).getFFANType() == FlatFlagActionNode.NEWOBJECT) {
- //***Debug Block***
- System.out.println("NEWObject");
- //***Debug Block***
-
-
- TempDescriptor[] tdArray = ((FlatFlagActionNode)nn).readsTemps();
-
- //Under the safe assumption that all the temps in FFAN.NewObject node are of the same type(class)
- ClassDescriptor cd_new=tdArray[0].getType().getClassDesc();
-
- System.out.println("Class: "+cd_new.getSymbol());
-
- FlagState fstemp=new FlagState((FlagDescriptor[])flags.get(cd_new), cd_new);
-
- for(Iterator it_tfp=((FlatFlagActionNode)nn).getTempFlagPairs();it_tfp.hasNext();) {
- TempFlagPair tfp=(TempFlagPair)it_tfp.next();
- if (tfp.getFlag()==null) {
- System.out.println("test1");
- q_retval.addAll(createPossibleRuntimeStates(new TriggerState(cd_new,new FlagState((FlagDescriptor[])flags.get(cd_new), cd_new))));
- // ****debug block********
- System.out.println("/***********contents of q ret**********/");
- for (Iterator it_qret=q_retval.iterator();it_qret.hasNext();) {
- TriggerState ts_qret=(TriggerState)it_qret.next();
- FlagState fs_qret=ts_qret.getState();
-
- System.out.println("FS : "+fs_qret.toString((FlagDescriptor [])flags.get(ts_qret.getClassDescriptor())));
- }
- System.out.println("/*********************************/");
- // ****debug block********
- } else
- fstemp.put(tfp.getFlag(),new Boolean(((FlatFlagActionNode)nn).getFlagChange(tfp)));
-
-
- }
-
- //***Debug Block***
- System.out.println("test2");
- System.out.println("Newobj fsworking "+fsworking.toString((FlagDescriptor [])flags.get(cd_new)));
- System.out.println("Newobj fstemp "+fstemp.toString((FlagDescriptor [])flags.get(cd_new)));
-
- //***Debug Block***
-
- q_retval.offer(new TriggerState(cd_new,fstemp));
-
- //make this a function containsExterns()
- int extrns=((Integer)extern_flags.get(cd_new)).intValue();
-
- if ((extrns >0) && (extrns!=((FlagDescriptor[])flags.get(cd_new)).length))
- q_retval.addAll(createPossibleRuntimeStates(new TriggerState(cd_new,fstemp)));
-
- fstemp=null;
- // ****debug block********
- System.out.println("/***********contents of q ret 1**********/");
- for (Iterator it_qret=q_retval.iterator();it_qret.hasNext();) {
- TriggerState ts_qret=(TriggerState)it_qret.next();
- FlagState fs_qret=ts_qret.getState();
-
- System.out.println("FS : "+fs_qret.toString((FlagDescriptor [])flags.get(ts_qret.getClassDescriptor())));
- }
- System.out.println("/*********************************/");
- // ****debug block********
-
- }
- if (((FlatFlagActionNode)nn).getFFANType() == FlatFlagActionNode.TASKEXIT) {
- //***Debug Block***
- //
- System.out.println("TaskExit");
- //***Debug Block***
-
- FlagState fstemp=new FlagState(fsworking.getStateTable(), null); //WHAT CLASS IS THIS
-
- for(Iterator it_tfp=((FlatFlagActionNode)nn).getTempFlagPairs();it_tfp.hasNext();) {
- TempFlagPair tfp=(TempFlagPair)it_tfp.next();
- fstemp.put(tfp.getFlag(),new Boolean(((FlatFlagActionNode)nn).getFlagChange(tfp)));
- }
- //***Debug Block***
- System.out.println();
- System.out.println(fstemp.toString((FlagDescriptor [])flags.get(cd)));
- System.out.println();
- System.out.println("taskexit fsworking "+fsworking.toString((FlagDescriptor [])flags.get(cd)));
- System.out.println("taskexit fstemp "+fstemp.toString((FlagDescriptor [])flags.get(cd)));
-
- //***Debug Block***
- if (!edgeexists(Adj_List_temp,fsworking,fstemp,taskname)) {
- ((Vector)Adj_List_temp.get(fsworking)).add(new Edge(fstemp,taskname));
- }
- if (!wasFlagStateProcessed(Adj_List_temp,fstemp)) {
- q.offer(fstemp);
- }
- fstemp=null;
-
- }
- }
-
- if (!visited.contains(nn) && !tovisit.contains(nn)) {
- tovisit.add(nn);
- }
- }
- }
- }
- }
- }
- if (q_retval.size()==0)
- return null;
- else
- return q_retval;
- }
-
- private boolean isTaskTrigger(FlagExpressionNode fen,FlagState fs) {
- if (fen instanceof FlagNode)
- return fs.get(((FlagNode)fen).getFlag());
- else
- switch (((FlagOpNode)fen).getOp().getOp()) {
- case Operation.LOGIC_AND:
- return ((isTaskTrigger(((FlagOpNode)fen).getLeft(),fs)) && (isTaskTrigger(((FlagOpNode)fen).getRight(),fs)));
- case Operation.LOGIC_OR:
- return ((isTaskTrigger(((FlagOpNode)fen).getLeft(),fs)) || (isTaskTrigger(((FlagOpNode)fen).getRight(),fs)));
- case Operation.LOGIC_NOT:
- return !(isTaskTrigger(((FlagOpNode)fen).getLeft(),fs));
- default:
- return false;
- }
- }
-
- private boolean wasFlagStateProcessed(Hashtable Adj_List,FlagState fs) {
- Enumeration e=Adj_List.keys();
-
- while(e.hasMoreElements()) {
- FlagState fsv = (FlagState)(e.nextElement());
-
- if (fsv.isEqual(fs))
- return true;
- }
- return false;
- }
-
- private boolean existsInQueue(TriggerState ts) {
- for(Iterator it_queue=q_main.iterator();it_queue.hasNext();) {
- TriggerState ts_local=(TriggerState)it_queue.next();
-
- if (ts_local.equals(ts))
- return true;
- }
- return false;
- }
-
- private boolean existsInFSQueue(Queue q,FlagState fs) {
- for (Iterator it_q=q.iterator();it_q.hasNext();) {
- if(((FlagState)it_q.next()).isEqual(fs))
- return true;
- }
- return false;
- }
-
- public void printAdjList(ClassDescriptor cd) {
- Enumeration e=((Hashtable)Adj_List.get(cd)).keys();
- while(e.hasMoreElements()) {
- FlagState fsv = (FlagState)(e.nextElement());
- System.out.println(fsv.toString((FlagDescriptor [])flags.get(cd)));
- }
- }
-
- public void createDOTfile(ClassDescriptor cd) throws java.io.IOException {
- File dotfile= new File("graph"+cd.getSymbol()+".dot");
-
- FileWriter dotwriter=new FileWriter(dotfile,true);
-
- dotwriter.write("digraph G{ \n");
- dotwriter.write("center=true;\norientation=landscape;\n");
-
- Enumeration e=((Hashtable)Adj_List.get(cd)).keys();
- while(e.hasMoreElements()) {
- FlagState fsv = (FlagState)(e.nextElement());
- System.out.println(fsv.toString());
- Hashtable test=(Hashtable)Adj_List.get(cd);
- Vector edges=(Vector)test.get(fsv);
- for(int i=0;i < edges.size();i++) {
- dotwriter.write(fsv.toString((FlagDescriptor [])flags.get(cd))+" -> "+((Edge)edges.get(i)).getState().toString((FlagDescriptor [])flags.get(cd))+"[label=\""+((Edge)edges.get(i)).getName()+"\"];\n");
- }
-
- }
- dotwriter.write("}\n");
- dotwriter.flush();
- dotwriter.close();
- }
-
- private String getTaskName(TaskDescriptor td) {
- StringTokenizer st = new StringTokenizer(td.toString(),"(");
- return st.nextToken();
- }
-
- private boolean edgeexists(Hashtable Adj_List_local,FlagState v1, FlagState v2,String name) {
- Vector edges=(Vector)Adj_List_local.get(v1);
-
- if (edges == null) {
- System.out.println("no edges");
- } else {
- for(int i=0;i < edges.size();i++) {
- FlagState fs=((Edge)edges.get(i)).getState();
- if (fs.isEqual(v2) && (name.compareTo(((Edge)edges.get(i)).getName())==0))
- return true;
- }
- }
- return false;
- }
-
- private void processExterns(boolean onlyExterns,ClassDescriptor cd) throws java.io.IOException {
- int noOfIterations;
- Hashtable Adj_List_temp;
- if (Adj_List.containsKey(cd)) {
- Adj_List_temp=(Hashtable)Adj_List.get(cd);
- } else {
- Adj_List_temp=new Hashtable();
- Adj_List.put(cd,Adj_List_temp);
- }
-
-
- if (onlyExterns) {
- FlagDescriptor [] fd=(FlagDescriptor [])flags.get(cd);
- System.out.println("onlyExterns"+fd.length);
- noOfIterations=1<<fd.length;
- boolean BoolValTable[]=new boolean[fd.length];
-
- for(int i=0; i < fd.length ; i++) {
- System.out.println(fd[i].getSymbol());
- BoolValTable[i]=false;
- }
- Adj_List_temp.put(new FlagState(fd,cd),new Vector());
-
- for(int k=1; k<noOfIterations; k++) {
- for(int j=0; j< fd.length ;j++) {
- if ((k% (1<<j)) == 0)
- BoolValTable[j]=(!BoolValTable[j]);
- }
-
- FlagState fstemp=new FlagState(fd,cd);
- int i=0;
- for(Enumeration e=fstemp.getStateTable().keys(); e.hasMoreElements() && i < fd.length;i++) {
- fstemp.put((FlagDescriptor)e.nextElement(),new Boolean(BoolValTable[i]));
- }
- Adj_List_temp.put(fstemp,new Vector());
- }
-
- Enumeration e=Adj_List_temp.keys();
- while(e.hasMoreElements()) {
- FlagState fstemp=(FlagState)e.nextElement();
- Enumeration en=Adj_List_temp.keys();
- while (en.hasMoreElements()) {
- FlagState fs=(FlagState)en.nextElement();
- if(fstemp == fs) {
- continue;
- } else {
- ((Vector)Adj_List_temp.get(fstemp)).add(new Edge(fs,"Runtime"));
- }
- }
- }
- }
- }
-
- private Queue createPossibleRuntimeStates(TriggerState ts) throws java.io.IOException {
- int noOfIterations, externs;
- Hashtable Adj_List_temp;
- boolean onlyExterns;
-
- System.out.println("Inside CreatePossible runtime states");
-
- ClassDescriptor cd = ts.getClassDescriptor();
- FlagState fs= ts.getState();
- if (Adj_List.containsKey(cd)) {
- Adj_List_temp=(Hashtable)Adj_List.get(cd);
- } else {
- Adj_List_temp=new Hashtable();
- Adj_List.put(cd,Adj_List_temp);
- }
-
- externs=((Integer)extern_flags.get(cd)).intValue();
-
- FlagDescriptor[] fd=(FlagDescriptor[])flags.get(cd);
-
- onlyExterns= (fd.length==externs);
-
- Queue q_ret=new LinkedList();
-
- if (onlyExterns) {
- noOfIterations=1<<fd.length;
- boolean BoolValTable[]=new boolean[fd.length];
-
- for(int i=0; i < fd.length ; i++) {
- System.out.println(fd[i].getSymbol());
- BoolValTable[i]=false;
- }
-
- if (! wasFlagStateProcessed(Adj_List_temp,fs)) {
- TriggerState ts_local=new TriggerState(cd,fs);
- if (!existsInQueue(ts_local)) {
- q_ret.offer(ts_local);
- }
- Adj_List_temp.put(fs,new Vector());
- }
-
- for(int k=1; k<noOfIterations; k++) {
- for(int j=0; j< fd.length ;j++) {
- if ((k% (1<<j))==0)
- BoolValTable[j]=(!BoolValTable[j]);
- }
-
- FlagState fstemp=new FlagState(fs.getStateTable(),cd);
- int i=0;
- for(Enumeration e=fstemp.getStateTable().keys(); e.hasMoreElements() && i < fd.length;i++) {
- fstemp.put((FlagDescriptor)e.nextElement(),new Boolean(BoolValTable[i]));
- }
-
- if (wasFlagStateProcessed(Adj_List_temp,fstemp)) {
- continue;
- } else {
- TriggerState ts_local=new TriggerState(cd,fstemp);
- if (!existsInQueue(ts_local)) {
- q_ret.offer(ts_local);
- }
-
-
- Adj_List_temp.put(fstemp,new Vector());
- }
-
- }
-
- Enumeration e=Adj_List_temp.keys();
- while(e.hasMoreElements()) {
- FlagState fstemp=(FlagState)e.nextElement();
- Enumeration en=Adj_List_temp.keys();
- while (en.hasMoreElements()) {
- FlagState fs_local=(FlagState)en.nextElement();
- if(fstemp == fs_local)
- continue;
- else
- ((Vector)Adj_List_temp.get(fstemp)).add(new Edge(fs_local,"Runtime"));
- }
- }
-
- return q_ret;
- } else {
- System.out.println("inside else part");
- noOfIterations=1<<externs;
- boolean BoolValTable[]=new boolean[externs];
- Hashtable Adj_List_local;
-
-
- Adj_List_local=new Hashtable();
-
- for(int i=0; i < externs ; i++) {
- System.out.println(fd[i].getSymbol());
- BoolValTable[i]=fs.get(fd[i]);
- }
-
- for(int k=1; k<noOfIterations; k++) {
- for(int j=0; j< fd.length ;j++) {
- if ((k% (1<<j))==0)
- BoolValTable[j]=(!BoolValTable[j]);
- }
-
- FlagState fstemp=new FlagState(fs.getStateTable(),cd);
- FlagDescriptor fdtemp[]=(FlagDescriptor [])flags.get(cd);
-
- for(int i=0; i < externs;i++)
- {
- fstemp.put(fdtemp[i],new Boolean(BoolValTable[i]));
- }
-
- q_ret.offer(new TriggerState(cd,fstemp));
- }
-
- return q_ret;
-
- }
- }
-
- private Queue createPossibleRuntimeStates(ClassDescriptor cd,FlagState fs) throws java.io.IOException {
- int noOfIterations, externs;
- Hashtable Adj_List_temp;
- boolean onlyExterns;
-
- System.out.println("Inside CreatePossible runtime states(flagstates)");
-
- if (Adj_List.containsKey(cd))
- Adj_List_temp=(Hashtable)Adj_List.get(cd);
- else {
- Adj_List_temp=new Hashtable();
- Adj_List.put(cd,Adj_List_temp);
- }
-
- externs=((Integer)extern_flags.get(cd)).intValue();
-
- FlagDescriptor[] fd=(FlagDescriptor[])flags.get(cd);
-
- onlyExterns=fd.length==externs;
-
- Queue q_ret;
-
- q_ret=new LinkedList();
-
- if (onlyExterns) {
- noOfIterations=1<<fd.length;
- boolean BoolValTable[]=new boolean[fd.length];
-
- for(int i=0; i < fd.length ; i++) {
- System.out.println(fd[i].getSymbol());
- BoolValTable[i]=false;
- }
-
- return q_ret;
- } else {
- System.out.println("inside else part(fs)");
- noOfIterations=1<<externs;
- boolean BoolValTable[]=new boolean[externs];
- Hashtable Adj_List_local;
-
-
- Adj_List_local=new Hashtable();
-
- for(int i=0; i < externs ; i++) {
- System.out.println(fd[i].getSymbol());
- BoolValTable[i]=fs.get(fd[i]);
- }
-
- if (! wasFlagStateProcessed(Adj_List_temp,fs)) {
- Adj_List_temp.put(fs,new Vector());
- }
- for(int k=1; k<noOfIterations; k++) {
- for(int j=0; j< fd.length ;j++) {
- if ((k% (1<<j))==0)
- BoolValTable[j]=(!BoolValTable[j]);
- }
-
- FlagState fstemp=new FlagState(fs.getStateTable(),cd);
- FlagDescriptor fdtemp[]=(FlagDescriptor [])flags.get(cd);
-
- for(int i=0; i < externs;i++) {
- fstemp.put(fdtemp[i],new Boolean(BoolValTable[i]));
- }
-
- q_ret.offer(fstemp);
- ((Vector)(Adj_List_temp.get(fs))).add(new Edge(fstemp,"Runtime"));
-
- }
- return q_ret;
-
- }
- }
-
-
- private void processTasksWithPost(ClassDescriptor cd, Hashtable pre) {
- }
-
- private ClassDescriptor processFlatNew(FlatNode fn) {
- if (! (fn.getNext(0).kind() == 13)) {
- return (((FlatNew)fn).getType().getClassDesc());
- }
- return null;
- }
-
-}
projects / IRC.git / blobdiff