3 import Analysis.CallGraph.*;
4 import Analysis.OwnershipAnalysis.*;
12 public class MLPAnalysis {
14 // data from the compiler
16 private TypeUtil typeUtil;
17 private CallGraph callGraph;
18 private OwnershipAnalysis ownAnalysis;
20 private SESENode rootTree;
21 private FlatSESEEnterNode rootSESE;
22 private FlatSESEExitNode rootExit;
24 private Hashtable< FlatNode, Stack<FlatSESEEnterNode> > seseStacks;
25 private Hashtable< FlatNode, Set<TempDescriptor> > livenessVirtualReads;
26 private Hashtable< FlatNode, VarSrcTokTable > variableResults;
27 private Hashtable< FlatNode, String > codePlan;
30 public MLPAnalysis( State state,
33 OwnershipAnalysis ownAnalysis
36 double timeStartAnalysis = (double) System.nanoTime();
40 this.callGraph = callGraph;
41 this.ownAnalysis = ownAnalysis;
43 // initialize analysis data structures
44 seseStacks = new Hashtable< FlatNode, Stack<FlatSESEEnterNode> >();
45 livenessVirtualReads = new Hashtable< FlatNode, Set<TempDescriptor> >();
46 variableResults = new Hashtable< FlatNode, VarSrcTokTable >();
47 codePlan = new Hashtable< FlatNode, String >();
50 // build an implicit root SESE to wrap contents of main method
51 rootTree = new SESENode( "root" );
52 rootSESE = new FlatSESEEnterNode( rootTree );
53 rootExit = new FlatSESEExitNode ( rootTree );
54 rootSESE.setFlatExit ( rootExit );
55 rootExit.setFlatEnter( rootSESE );
57 FlatMethod fmMain = state.getMethodFlat( tu.getMain() );
61 // run analysis on each method that is actually called
62 // reachability analysis already computed this so reuse
63 Iterator<Descriptor> methItr = ownAnalysis.descriptorsToAnalyze.iterator();
64 while( methItr.hasNext() ) {
65 Descriptor d = methItr.next();
66 FlatMethod fm = state.getMethodFlat( d );
68 // find every SESE from methods that may be called
69 // and organize them into roots and children
70 buildForestForward( fm );
74 // 2nd pass, results are saved in FlatSESEEnterNode, so
75 // intermediate results, for safety, are discarded
76 livenessAnalysisBackward( rootSESE, true, null, fmMain.getFlatExit() );
80 methItr = ownAnalysis.descriptorsToAnalyze.iterator();
81 while( methItr.hasNext() ) {
82 Descriptor d = methItr.next();
83 FlatMethod fm = state.getMethodFlat( d );
85 // starting from roots do a forward, fixed-point
86 // variable analysis for refinement and stalls
87 variableAnalysisForward( fm );
91 // 4th pass, compute liveness contribution from
92 // virtual reads discovered in variable pass
93 livenessAnalysisBackward( rootSESE, true, null, fmMain.getFlatExit() );
97 methItr = ownAnalysis.descriptorsToAnalyze.iterator();
98 while( methItr.hasNext() ) {
99 Descriptor d = methItr.next();
100 FlatMethod fm = state.getMethodFlat( d );
102 // compute a plan for code injections
103 computeStallsForward( fm );
107 double timeEndAnalysis = (double) System.nanoTime();
108 double dt = (timeEndAnalysis - timeStartAnalysis)/(Math.pow( 10.0, 9.0 ) );
109 String treport = String.format( "The mlp analysis took %.3f sec.", dt );
110 System.out.println( treport );
114 private void buildForestForward( FlatMethod fm ) {
116 // start from flat method top, visit every node in
117 // method exactly once, find SESEs and remember
118 // roots and child relationships
119 Set<FlatNode> flatNodesToVisit = new HashSet<FlatNode>();
120 flatNodesToVisit.add( fm );
122 Set<FlatNode> visited = new HashSet<FlatNode>();
124 Stack<FlatSESEEnterNode> seseStackFirst = new Stack<FlatSESEEnterNode>();
125 seseStackFirst.push( rootSESE );
126 seseStacks.put( fm, seseStackFirst );
128 while( !flatNodesToVisit.isEmpty() ) {
129 Iterator<FlatNode> fnItr = flatNodesToVisit.iterator();
130 FlatNode fn = fnItr.next();
132 Stack<FlatSESEEnterNode> seseStack = seseStacks.get( fn );
133 assert seseStack != null;
135 flatNodesToVisit.remove( fn );
138 buildForest_nodeActions( fn, seseStack );
140 for( int i = 0; i < fn.numNext(); i++ ) {
141 FlatNode nn = fn.getNext( i );
143 if( !visited.contains( nn ) ) {
144 flatNodesToVisit.add( nn );
146 // clone stack and send along each analysis path
147 seseStacks.put( nn, (Stack<FlatSESEEnterNode>)seseStack.clone() );
152 if( state.MLPDEBUG ) {
157 private void buildForest_nodeActions( FlatNode fn,
158 Stack<FlatSESEEnterNode> seseStack ) {
159 switch( fn.kind() ) {
161 case FKind.FlatSESEEnterNode: {
162 FlatSESEEnterNode fsen = (FlatSESEEnterNode) fn;
163 assert !seseStack.empty();
164 seseStack.peek().addChild( fsen );
165 fsen.setParent( seseStack.peek() );
166 seseStack.push( fsen );
169 case FKind.FlatSESEExitNode: {
170 FlatSESEExitNode fsexn = (FlatSESEExitNode) fn;
171 assert !seseStack.empty();
172 FlatSESEEnterNode fsen = seseStack.pop();
175 case FKind.FlatReturnNode: {
176 FlatReturnNode frn = (FlatReturnNode) fn;
177 if( !seseStack.empty() &&
178 !seseStack.peek().equals( rootSESE ) ) {
179 throw new Error( "Error: return statement enclosed within "+seseStack.peek() );
186 private void printSESEForest() {
187 // our forest is actually a tree now that
188 // there is an implicit root SESE
189 printSESETree( rootSESE, 0 );
190 System.out.println( "" );
193 private void printSESETree( FlatSESEEnterNode fsen, int depth ) {
194 for( int i = 0; i < depth; ++i ) {
195 System.out.print( " " );
197 System.out.println( fsen.getPrettyIdentifier() );
199 Iterator<FlatSESEEnterNode> childItr = fsen.getChildren().iterator();
200 while( childItr.hasNext() ) {
201 FlatSESEEnterNode fsenChild = childItr.next();
202 printSESETree( fsenChild, depth + 1 );
207 private void livenessAnalysisBackward( FlatSESEEnterNode fsen, boolean toplevel, Hashtable<FlatSESEExitNode, Set<TempDescriptor>> liveout, FlatExit fexit) {
208 // start from an SESE exit, visit nodes in reverse up to
209 // SESE enter in a fixed-point scheme, where children SESEs
210 // should already be analyzed and therefore can be skipped
211 // because child SESE enter node has all necessary info
212 Set<FlatNode> flatNodesToVisit = new HashSet<FlatNode>();
214 FlatSESEExitNode fsexn = fsen.getFlatExit();
217 flatNodesToVisit.add( fexit );
219 flatNodesToVisit.add( fsexn );
220 Hashtable<FlatNode, Set<TempDescriptor>> livenessResults=new Hashtable<FlatNode, Set<TempDescriptor>>();
223 liveout=new Hashtable<FlatSESEExitNode, Set<TempDescriptor>>();
225 while( !flatNodesToVisit.isEmpty() ) {
226 FlatNode fn = (FlatNode) flatNodesToVisit.iterator().next();
227 flatNodesToVisit.remove( fn );
229 Set<TempDescriptor> prev = livenessResults.get( fn );
231 // merge sets from control flow joins
232 Set<TempDescriptor> u = new HashSet<TempDescriptor>();
233 for( int i = 0; i < fn.numNext(); i++ ) {
234 FlatNode nn = fn.getNext( i );
235 Set<TempDescriptor> s = livenessResults.get( nn );
241 Set<TempDescriptor> curr = liveness_nodeActions( fn, u, fsen, toplevel, liveout);
243 // if a new result, schedule backward nodes for analysis
244 if(!curr.equals(prev)) {
245 livenessResults.put( fn, curr );
247 // don't flow backwards past current SESE enter
248 if( !fn.equals( fsen ) ) {
249 for( int i = 0; i < fn.numPrev(); i++ ) {
250 FlatNode nn = fn.getPrev( i );
251 flatNodesToVisit.add( nn );
257 Set<TempDescriptor> s = livenessResults.get( fsen );
259 fsen.addInVarSet( s );
262 if( state.MLPDEBUG ) {
263 System.out.println( "SESE "+fsen.getPrettyIdentifier()+" has in-set:" );
264 Iterator<TempDescriptor> tItr = fsen.getInVarSet().iterator();
265 while( tItr.hasNext() ) {
266 System.out.println( " "+tItr.next() );
268 System.out.println( "and out-set:" );
269 tItr = fsen.getOutVarSet().iterator();
270 while( tItr.hasNext() ) {
271 System.out.println( " "+tItr.next() );
273 System.out.println( "" );
275 // post-order traversal, so do children first
276 Iterator<FlatSESEEnterNode> childItr = fsen.getChildren().iterator();
277 while( childItr.hasNext() ) {
278 FlatSESEEnterNode fsenChild = childItr.next();
279 livenessAnalysisBackward( fsenChild, false, liveout, null);
283 private Set<TempDescriptor> liveness_nodeActions( FlatNode fn,
284 Set<TempDescriptor> liveIn,
285 FlatSESEEnterNode currentSESE,
287 Hashtable<FlatSESEExitNode, Set<TempDescriptor>> liveout) {
289 switch( fn.kind() ) {
291 case FKind.FlatSESEExitNode:
292 if (toplevel==true) {
293 FlatSESEExitNode exitn=(FlatSESEExitNode) fn;
294 //update liveout set for FlatSESEExitNode
295 if (!liveout.containsKey(exitn))
296 liveout.put(exitn, new HashSet<TempDescriptor>());
297 liveout.get(exitn).addAll(liveIn);
299 // no break, sese exits should also execute default actions
302 // handle effects of statement in reverse, writes then reads
303 TempDescriptor [] writeTemps = fn.writesTemps();
304 for( int i = 0; i < writeTemps.length; ++i ) {
305 liveIn.remove( writeTemps[i] );
308 FlatSESEExitNode exitnode=currentSESE.getFlatExit();
309 Set<TempDescriptor> livetemps=liveout.get(exitnode);
310 if (livetemps.contains(writeTemps[i])) {
311 //write to a live out temp...
312 //need to put in SESE liveout set
313 currentSESE.addOutVar(writeTemps[i]);
318 TempDescriptor [] readTemps = fn.readsTemps();
319 for( int i = 0; i < readTemps.length; ++i ) {
320 liveIn.add( readTemps[i] );
323 Set<TempDescriptor> virtualReadTemps = livenessVirtualReads.get( fn );
324 if( virtualReadTemps != null ) {
325 Iterator<TempDescriptor> vrItr = virtualReadTemps.iterator();
326 while( vrItr.hasNext() ) {
327 liveIn.add( vrItr.next() );
338 private void variableAnalysisForward( FlatMethod fm ) {
340 Set<FlatNode> flatNodesToVisit = new HashSet<FlatNode>();
341 flatNodesToVisit.add( fm );
343 while( !flatNodesToVisit.isEmpty() ) {
344 FlatNode fn = (FlatNode) flatNodesToVisit.iterator().next();
345 flatNodesToVisit.remove( fn );
347 Stack<FlatSESEEnterNode> seseStack = seseStacks.get( fn );
348 assert seseStack != null;
350 VarSrcTokTable prev = variableResults.get( fn );
352 // merge sets from control flow joins
353 VarSrcTokTable inUnion = new VarSrcTokTable();
354 for( int i = 0; i < fn.numPrev(); i++ ) {
355 FlatNode nn = fn.getPrev( i );
357 inUnion.merge( variableResults.get( nn ) );
360 VarSrcTokTable curr = variable_nodeActions( fn, inUnion, seseStack.peek() );
362 // if a new result, schedule forward nodes for analysis
363 if( !curr.equals( prev ) ) {
365 variableResults.put( fn, curr );
367 for( int i = 0; i < fn.numNext(); i++ ) {
368 FlatNode nn = fn.getNext( i );
369 flatNodesToVisit.add( nn );
375 private VarSrcTokTable variable_nodeActions( FlatNode fn,
376 VarSrcTokTable vstTable,
377 FlatSESEEnterNode currentSESE ) {
378 switch( fn.kind() ) {
380 case FKind.FlatSESEEnterNode: {
381 FlatSESEEnterNode fsen = (FlatSESEEnterNode) fn;
382 assert fsen.equals( currentSESE );
383 vstTable.age( currentSESE );
386 case FKind.FlatSESEExitNode: {
387 FlatSESEExitNode fsexn = (FlatSESEExitNode) fn;
388 FlatSESEEnterNode fsen = fsexn.getFlatEnter();
389 assert currentSESE.getChildren().contains( fsen );
390 vstTable.remapChildTokens( fsen );
392 Set<TempDescriptor> liveIn = currentSESE.getInVarSet();
393 Set<TempDescriptor> virLiveIn = vstTable.removeParentAndSiblingTokens( fsen, liveIn );
394 Set<TempDescriptor> virLiveInOld = livenessVirtualReads.get( fn );
395 if( virLiveInOld != null ) {
396 virLiveIn.addAll( virLiveInOld );
398 livenessVirtualReads.put( fn, virLiveIn );
401 case FKind.FlatOpNode: {
402 FlatOpNode fon = (FlatOpNode) fn;
404 if( fon.getOp().getOp() == Operation.ASSIGN ) {
405 TempDescriptor lhs = fon.getDest();
406 TempDescriptor rhs = fon.getLeft();
408 vstTable.remove( lhs );
410 Iterator<VariableSourceToken> itr = vstTable.get( rhs ).iterator();
411 while( itr.hasNext() ) {
412 VariableSourceToken vst = itr.next();
414 HashSet<TempDescriptor> ts = new HashSet<TempDescriptor>();
417 // if this is from a child, keep the source information
418 if( currentSESE.getChildren().contains( vst.getSESE() ) ) {
419 vstTable.add( new VariableSourceToken( ts,
426 // otherwise, it's our or an ancestor's token so we
427 // can assume we have everything we need
429 vstTable.add( new VariableSourceToken( ts,
438 // only break if this is an ASSIGN op node,
439 // otherwise fall through to default case
444 // note that FlatOpNode's that aren't ASSIGN
445 // fall through to this default case
447 TempDescriptor [] writeTemps = fn.writesTemps();
448 if( writeTemps.length > 0 ) {
449 assert writeTemps.length == 1;
451 vstTable.remove( writeTemps[0] );
453 HashSet<TempDescriptor> ts = new HashSet<TempDescriptor>();
454 ts.add( writeTemps[0] );
456 vstTable.add( new VariableSourceToken( ts,
471 private void computeStallsForward( FlatMethod fm ) {
473 // start from flat method top, visit every node in
474 // method exactly once
475 Set<FlatNode> flatNodesToVisit = new HashSet<FlatNode>();
476 flatNodesToVisit.add( fm );
478 Set<FlatNode> visited = new HashSet<FlatNode>();
480 while( !flatNodesToVisit.isEmpty() ) {
481 Iterator<FlatNode> fnItr = flatNodesToVisit.iterator();
482 FlatNode fn = fnItr.next();
484 flatNodesToVisit.remove( fn );
487 Stack<FlatSESEEnterNode> seseStack = seseStacks.get( fn );
488 assert seseStack != null;
490 // use incoming results as "dot statement" or just
491 // before the current statement
492 VarSrcTokTable dotST = new VarSrcTokTable();
493 for( int i = 0; i < fn.numPrev(); i++ ) {
494 FlatNode nn = fn.getPrev( i );
495 dotST.merge( variableResults.get( nn ) );
498 computeStalls_nodeActions( fn, dotST, seseStack.peek() );
500 for( int i = 0; i < fn.numNext(); i++ ) {
501 FlatNode nn = fn.getNext( i );
503 if( !visited.contains( nn ) ) {
504 flatNodesToVisit.add( nn );
509 if( state.MLPDEBUG ) {
510 System.out.println( fm.printMethod( codePlan ) );
514 private void computeStalls_nodeActions( FlatNode fn,
515 VarSrcTokTable vstTable,
516 FlatSESEEnterNode currentSESE ) {
519 switch( fn.kind() ) {
521 case FKind.FlatSESEEnterNode: {
522 FlatSESEEnterNode fsen = (FlatSESEEnterNode) fn;
525 case FKind.FlatSESEExitNode: {
526 FlatSESEExitNode fsexn = (FlatSESEExitNode) fn;
530 Set<VariableSourceToken> stallSet = vstTable.getStallSet( currentSESE );
531 TempDescriptor[] readarray=fn.readsTemps();
532 for(int i=0;i<readarray.length;i++) {
533 TempDescriptor readtmp=readarray[i];
534 Set<VariableSourceToken> readSet = vstTable.get(readtmp);
536 for(Iterator<VariableSourceToken> readit=readSet.iterator();readit.hasNext();) {
537 VariableSourceToken vst=readit.next();
538 if (stallSet.contains(vst)) {
541 s+="("+vst+" "+readtmp+")";
552 codePlan.put( fn, s );