AnalysisConsumer.cpp revision 3bbd8cd831788c506f2980293eb3c7e1b3ca2501 
1//===--- AnalysisConsumer.cpp - ASTConsumer for running Analyses ----------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// "Meta" ASTConsumer for running different source analyses.
11//
12//===----------------------------------------------------------------------===//
13
14#define DEBUG_TYPE "AnalysisConsumer"
15
16#include "AnalysisConsumer.h"
17#include "clang/AST/ASTConsumer.h"
18#include "clang/AST/Decl.h"
19#include "clang/AST/DeclCXX.h"
20#include "clang/AST/DeclObjC.h"
21#include "clang/AST/ParentMap.h"
22#include "clang/AST/RecursiveASTVisitor.h"
23#include "clang/Analysis/CFG.h"
24#include "clang/Analysis/CallGraph.h"
25#include "clang/StaticAnalyzer/Frontend/CheckerRegistration.h"
26#include "clang/StaticAnalyzer/Core/CheckerManager.h"
27#include "clang/StaticAnalyzer/Checkers/LocalCheckers.h"
28#include "clang/StaticAnalyzer/Core/BugReporter/PathDiagnostic.h"
29#include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
30#include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
31#include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
32#include "clang/StaticAnalyzer/Core/PathDiagnosticConsumers.h"
33
34#include "clang/Basic/FileManager.h"
35#include "clang/Basic/SourceManager.h"
36#include "clang/Frontend/AnalyzerOptions.h"
37#include "clang/Lex/Preprocessor.h"
38#include "llvm/Support/raw_ostream.h"
39#include "llvm/Support/Path.h"
40#include "llvm/Support/Program.h"
41#include "llvm/Support/Timer.h"
42#include "llvm/ADT/DepthFirstIterator.h"
43#include "llvm/ADT/OwningPtr.h"
44#include "llvm/ADT/Statistic.h"
45
46#include <queue>
47
48using namespace clang;
49using namespace ento;
50using llvm::SmallPtrSet;
51
52static ExplodedNode::Auditor* CreateUbiViz();
53
54STATISTIC(NumFunctionTopLevel, "The # of functions at top level.");
55STATISTIC(NumFunctionsAnalyzed, "The # of functions analysed (as top level).");
56
57//===----------------------------------------------------------------------===//
58// Special PathDiagnosticConsumers.
59//===----------------------------------------------------------------------===//
60
61static PathDiagnosticConsumer*
62createPlistHTMLDiagnosticConsumer(const std::string& prefix,
63                                const Preprocessor &PP) {
64  PathDiagnosticConsumer *PD =
65    createHTMLDiagnosticConsumer(llvm::sys::path::parent_path(prefix), PP);
66  return createPlistDiagnosticConsumer(prefix, PP, PD);
67}
68
69//===----------------------------------------------------------------------===//
70// AnalysisConsumer declaration.
71//===----------------------------------------------------------------------===//
72
73namespace {
74
75class AnalysisConsumer : public ASTConsumer,
76                         public RecursiveASTVisitor<AnalysisConsumer> {
77  enum AnalysisMode {
78    ANALYSIS_SYNTAX,
79    ANALYSIS_PATH,
80    ANALYSIS_ALL
81  };
82
83  /// Mode of the analyzes while recursively visiting Decls.
84  AnalysisMode RecVisitorMode;
85  /// Bug Reporter to use while recursively visiting Decls.
86  BugReporter *RecVisitorBR;
87
88public:
89  ASTContext *Ctx;
90  const Preprocessor &PP;
91  const std::string OutDir;
92  AnalyzerOptions Opts;
93  ArrayRef<std::string> Plugins;
94
95  // PD is owned by AnalysisManager.
96  PathDiagnosticConsumer *PD;
97
98  StoreManagerCreator CreateStoreMgr;
99  ConstraintManagerCreator CreateConstraintMgr;
100
101  OwningPtr<CheckerManager> checkerMgr;
102  OwningPtr<AnalysisManager> Mgr;
103
104  /// Time the analyzes time of each translation unit.
105  static llvm::Timer* TUTotalTimer;
106
107  /// The information about analyzed functions shared throughout the
108  /// translation unit.
109  FunctionSummariesTy FunctionSummaries;
110
111  AnalysisConsumer(const Preprocessor& pp,
112                   const std::string& outdir,
113                   const AnalyzerOptions& opts,
114                   ArrayRef<std::string> plugins)
115    : RecVisitorMode(ANALYSIS_ALL), RecVisitorBR(0),
116      Ctx(0), PP(pp), OutDir(outdir), Opts(opts), Plugins(plugins), PD(0) {
117    DigestAnalyzerOptions();
118    if (Opts.PrintStats) {
119      llvm::EnableStatistics();
120      TUTotalTimer = new llvm::Timer("Analyzer Total Time");
121    }
122  }
123
124  ~AnalysisConsumer() {
125    if (Opts.PrintStats)
126      delete TUTotalTimer;
127  }
128
129  void DigestAnalyzerOptions() {
130    // Create the PathDiagnosticConsumer.
131    if (!OutDir.empty()) {
132      switch (Opts.AnalysisDiagOpt) {
133      default:
134#define ANALYSIS_DIAGNOSTICS(NAME, CMDFLAG, DESC, CREATEFN, AUTOCREATE) \
135        case PD_##NAME: PD = CREATEFN(OutDir, PP); break;
136#include "clang/Frontend/Analyses.def"
137      }
138    } else if (Opts.AnalysisDiagOpt == PD_TEXT) {
139      // Create the text client even without a specified output file since
140      // it just uses diagnostic notes.
141      PD = createTextPathDiagnosticConsumer("", PP);
142    }
143
144    // Create the analyzer component creators.
145    switch (Opts.AnalysisStoreOpt) {
146    default:
147      llvm_unreachable("Unknown store manager.");
148#define ANALYSIS_STORE(NAME, CMDFLAG, DESC, CREATEFN)           \
149      case NAME##Model: CreateStoreMgr = CREATEFN; break;
150#include "clang/Frontend/Analyses.def"
151    }
152
153    switch (Opts.AnalysisConstraintsOpt) {
154    default:
155      llvm_unreachable("Unknown store manager.");
156#define ANALYSIS_CONSTRAINTS(NAME, CMDFLAG, DESC, CREATEFN)     \
157      case NAME##Model: CreateConstraintMgr = CREATEFN; break;
158#include "clang/Frontend/Analyses.def"
159    }
160  }
161
162  void DisplayFunction(const Decl *D, AnalysisMode Mode) {
163    if (!Opts.AnalyzerDisplayProgress)
164      return;
165
166    SourceManager &SM = Mgr->getASTContext().getSourceManager();
167    PresumedLoc Loc = SM.getPresumedLoc(D->getLocation());
168    if (Loc.isValid()) {
169      llvm::errs() << "ANALYZE";
170      switch (Mode) {
171        case ANALYSIS_SYNTAX: llvm::errs() << "(Syntax)"; break;
172        case ANALYSIS_PATH: llvm::errs() << "(Path Sensitive)"; break;
173        case ANALYSIS_ALL: break;
174      };
175      llvm::errs() << ": " << Loc.getFilename();
176      if (isa<FunctionDecl>(D) || isa<ObjCMethodDecl>(D)) {
177        const NamedDecl *ND = cast<NamedDecl>(D);
178        llvm::errs() << ' ' << *ND << '\n';
179      }
180      else if (isa<BlockDecl>(D)) {
181        llvm::errs() << ' ' << "block(line:" << Loc.getLine() << ",col:"
182                     << Loc.getColumn() << '\n';
183      }
184      else if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
185        Selector S = MD->getSelector();
186        llvm::errs() << ' ' << S.getAsString();
187      }
188    }
189  }
190
191  virtual void Initialize(ASTContext &Context) {
192    Ctx = &Context;
193    checkerMgr.reset(createCheckerManager(Opts, PP.getLangOpts(), Plugins,
194                                          PP.getDiagnostics()));
195    Mgr.reset(new AnalysisManager(*Ctx, PP.getDiagnostics(),
196                                  PP.getLangOpts(), PD,
197                                  CreateStoreMgr, CreateConstraintMgr,
198                                  checkerMgr.get(),
199                                  /* Indexer */ 0,
200                                  Opts.MaxNodes, Opts.MaxLoop,
201                                  Opts.VisualizeEGDot, Opts.VisualizeEGUbi,
202                                  Opts.AnalysisPurgeOpt, Opts.EagerlyAssume,
203                                  Opts.TrimGraph,
204                                  Opts.UnoptimizedCFG, Opts.CFGAddImplicitDtors,
205                                  Opts.CFGAddInitializers,
206                                  Opts.EagerlyTrimEGraph,
207                                  Opts.IPAMode,
208                                  Opts.InlineMaxStackDepth,
209                                  Opts.InlineMaxFunctionSize,
210                                  Opts.InliningMode,
211                                  Opts.NoRetryExhausted));
212  }
213
214  virtual void HandleTranslationUnit(ASTContext &C);
215
216  /// \brief Build the call graph for the TU and use it to define the order
217  /// in which the functions should be visited.
218  void HandleDeclsGallGraph(TranslationUnitDecl *TU);
219
220  /// \brief Run analyzes(syntax or path sensitive) on the given function.
221  /// \param Mode - determines if we are requesting syntax only or path
222  /// sensitive only analysis.
223  /// \param VisitedCallees - The output parameter, which is populated with the
224  /// set of functions which should be considered analyzed after analyzing the
225  /// given root function.
226  void HandleCode(Decl *D, AnalysisMode Mode, SetOfDecls *VisitedCallees = 0);
227
228  /// \brief Check if we should skip (not analyze) the given function.
229  bool skipFunction(Decl *D);
230
231  void RunPathSensitiveChecks(Decl *D, SetOfDecls *VisitedCallees);
232  void ActionExprEngine(Decl *D, bool ObjCGCEnabled, SetOfDecls *VisitedCallees);
233
234  /// Visitors for the RecursiveASTVisitor.
235
236  /// Handle callbacks for arbitrary Decls.
237  bool VisitDecl(Decl *D) {
238    checkerMgr->runCheckersOnASTDecl(D, *Mgr, *RecVisitorBR);
239    return true;
240  }
241
242  bool VisitFunctionDecl(FunctionDecl *FD) {
243    IdentifierInfo *II = FD->getIdentifier();
244    if (II && II->getName().startswith("__inline"))
245      return true;
246
247    // We skip function template definitions, as their semantics is
248    // only determined when they are instantiated.
249    if (FD->isThisDeclarationADefinition() &&
250        !FD->isDependentContext()) {
251      HandleCode(FD, RecVisitorMode);
252    }
253    return true;
254  }
255
256  bool VisitObjCMethodDecl(ObjCMethodDecl *MD) {
257    checkerMgr->runCheckersOnASTDecl(MD, *Mgr, *RecVisitorBR);
258    if (MD->isThisDeclarationADefinition())
259      HandleCode(MD, RecVisitorMode);
260    return true;
261  }
262};
263} // end anonymous namespace
264
265
266//===----------------------------------------------------------------------===//
267// AnalysisConsumer implementation.
268//===----------------------------------------------------------------------===//
269llvm::Timer* AnalysisConsumer::TUTotalTimer = 0;
270
271void AnalysisConsumer::HandleDeclsGallGraph(TranslationUnitDecl *TU) {
272  // Otherwise, use the Callgraph to derive the order.
273  // Build the Call Graph.
274  CallGraph CG;
275  CG.addToCallGraph(TU);
276
277  // Find the top level nodes - children of root + the unreachable (parentless)
278  // nodes.
279  llvm::SmallVector<CallGraphNode*, 24> TopLevelFunctions;
280  for (CallGraph::nodes_iterator TI = CG.parentless_begin(),
281                                 TE = CG.parentless_end(); TI != TE; ++TI) {
282    TopLevelFunctions.push_back(*TI);
283    NumFunctionTopLevel++;
284  }
285  CallGraphNode *Entry = CG.getRoot();
286  for (CallGraphNode::iterator I = Entry->begin(),
287                               E = Entry->end(); I != E; ++I) {
288    TopLevelFunctions.push_back(*I);
289    NumFunctionTopLevel++;
290  }
291
292  // Make sure the nodes are sorted in order reverse of their definition in the
293  // translation unit. This step is very important for performance. It ensures
294  // that we analyze the root functions before the externally available
295  // subroutines.
296  std::queue<CallGraphNode*> BFSQueue;
297  for (llvm::SmallVector<CallGraphNode*, 24>::reverse_iterator
298         TI = TopLevelFunctions.rbegin(), TE = TopLevelFunctions.rend();
299         TI != TE; ++TI)
300    BFSQueue.push(*TI);
301
302  // BFS over all of the functions, while skipping the ones inlined into
303  // the previously processed functions. Use external Visited set, which is
304  // also modified when we inline a function.
305  SmallPtrSet<CallGraphNode*,24> Visited;
306  while(!BFSQueue.empty()) {
307    CallGraphNode *N = BFSQueue.front();
308    BFSQueue.pop();
309
310    // Skip the functions which have been processed already or previously
311    // inlined.
312    if (Visited.count(N))
313      continue;
314
315    // Analyze the function.
316    SetOfDecls VisitedCallees;
317    Decl *D = N->getDecl();
318    assert(D);
319    HandleCode(D, ANALYSIS_PATH,
320               (Mgr->InliningMode == All ? 0 : &VisitedCallees));
321
322    // Add the visited callees to the global visited set.
323    for (SetOfDecls::const_iterator I = VisitedCallees.begin(),
324                                    E = VisitedCallees.end(); I != E; ++I) {
325      CallGraphNode *VN = CG.getNode(*I);
326      if (VN)
327        Visited.insert(VN);
328    }
329    Visited.insert(N);
330
331    // Push the children into the queue.
332    for (CallGraphNode::const_iterator CI = N->begin(),
333                                       CE = N->end(); CI != CE; ++CI) {
334      BFSQueue.push(*CI);
335    }
336  }
337}
338
339void AnalysisConsumer::HandleTranslationUnit(ASTContext &C) {
340  // Don't run the actions if an error has occurred with parsing the file.
341  DiagnosticsEngine &Diags = PP.getDiagnostics();
342  if (Diags.hasErrorOccurred() || Diags.hasFatalErrorOccurred())
343    return;
344
345  {
346    if (TUTotalTimer) TUTotalTimer->startTimer();
347
348    // Introduce a scope to destroy BR before Mgr.
349    BugReporter BR(*Mgr);
350    TranslationUnitDecl *TU = C.getTranslationUnitDecl();
351    checkerMgr->runCheckersOnASTDecl(TU, *Mgr, BR);
352
353    // Run the AST-only checks using the order in which functions are defined.
354    // If inlining is not turned on, use the simplest function order for path
355    // sensitive analyzes as well.
356    RecVisitorMode = (Mgr->shouldInlineCall() ? ANALYSIS_SYNTAX : ANALYSIS_ALL);
357    RecVisitorBR = &BR;
358    TraverseDecl(TU);
359
360    if (Mgr->shouldInlineCall())
361      HandleDeclsGallGraph(TU);
362
363    // After all decls handled, run checkers on the entire TranslationUnit.
364    checkerMgr->runCheckersOnEndOfTranslationUnit(TU, *Mgr, BR);
365
366    RecVisitorBR = 0;
367  }
368
369  // Explicitly destroy the PathDiagnosticConsumer.  This will flush its output.
370  // FIXME: This should be replaced with something that doesn't rely on
371  // side-effects in PathDiagnosticConsumer's destructor. This is required when
372  // used with option -disable-free.
373  Mgr.reset(NULL);
374
375  if (TUTotalTimer) TUTotalTimer->stopTimer();
376}
377
378static void FindBlocks(DeclContext *D, SmallVectorImpl<Decl*> &WL) {
379  if (BlockDecl *BD = dyn_cast<BlockDecl>(D))
380    WL.push_back(BD);
381
382  for (DeclContext::decl_iterator I = D->decls_begin(), E = D->decls_end();
383       I!=E; ++I)
384    if (DeclContext *DC = dyn_cast<DeclContext>(*I))
385      FindBlocks(DC, WL);
386}
387
388static std::string getFunctionName(const Decl *D) {
389  if (const ObjCMethodDecl *ID = dyn_cast<ObjCMethodDecl>(D)) {
390    return ID->getSelector().getAsString();
391  }
392  if (const FunctionDecl *ND = dyn_cast<FunctionDecl>(D)) {
393    IdentifierInfo *II = ND->getIdentifier();
394    if (II)
395      return II->getName();
396  }
397  return "";
398}
399
400bool AnalysisConsumer::skipFunction(Decl *D) {
401  if (!Opts.AnalyzeSpecificFunction.empty() &&
402      getFunctionName(D) != Opts.AnalyzeSpecificFunction)
403    return true;
404
405  // Don't run the actions on declarations in header files unless
406  // otherwise specified.
407  SourceManager &SM = Ctx->getSourceManager();
408  SourceLocation SL = SM.getExpansionLoc(D->getLocation());
409  if (!Opts.AnalyzeAll && !SM.isFromMainFile(SL))
410    return true;
411
412  return false;
413}
414
415void AnalysisConsumer::HandleCode(Decl *D, AnalysisMode Mode,
416                                  SetOfDecls *VisitedCallees) {
417  if (skipFunction(D))
418    return;
419
420  DisplayFunction(D, Mode);
421
422  // Clear the AnalysisManager of old AnalysisDeclContexts.
423  Mgr->ClearContexts();
424
425  // Dispatch on the actions.
426  SmallVector<Decl*, 10> WL;
427  WL.push_back(D);
428
429  if (D->hasBody() && Opts.AnalyzeNestedBlocks)
430    FindBlocks(cast<DeclContext>(D), WL);
431
432  BugReporter BR(*Mgr);
433  for (SmallVectorImpl<Decl*>::iterator WI=WL.begin(), WE=WL.end();
434       WI != WE; ++WI)
435    if ((*WI)->hasBody()) {
436      if (Mode != ANALYSIS_PATH)
437        checkerMgr->runCheckersOnASTBody(*WI, *Mgr, BR);
438      if (Mode != ANALYSIS_SYNTAX && checkerMgr->hasPathSensitiveCheckers()) {
439        RunPathSensitiveChecks(*WI, VisitedCallees);
440        NumFunctionsAnalyzed++;
441      }
442    }
443}
444
445//===----------------------------------------------------------------------===//
446// Path-sensitive checking.
447//===----------------------------------------------------------------------===//
448
449void AnalysisConsumer::ActionExprEngine(Decl *D, bool ObjCGCEnabled,
450                                        SetOfDecls *VisitedCallees) {
451  // Construct the analysis engine.  First check if the CFG is valid.
452  // FIXME: Inter-procedural analysis will need to handle invalid CFGs.
453  if (!Mgr->getCFG(D))
454    return;
455
456  ExprEngine Eng(*Mgr, ObjCGCEnabled, VisitedCallees, &FunctionSummaries);
457
458  // Set the graph auditor.
459  OwningPtr<ExplodedNode::Auditor> Auditor;
460  if (Mgr->shouldVisualizeUbigraph()) {
461    Auditor.reset(CreateUbiViz());
462    ExplodedNode::SetAuditor(Auditor.get());
463  }
464
465  // Execute the worklist algorithm.
466  Eng.ExecuteWorkList(Mgr->getAnalysisDeclContextManager().getStackFrame(D, 0),
467                      Mgr->getMaxNodes());
468
469  // Release the auditor (if any) so that it doesn't monitor the graph
470  // created BugReporter.
471  ExplodedNode::SetAuditor(0);
472
473  // Visualize the exploded graph.
474  if (Mgr->shouldVisualizeGraphviz())
475    Eng.ViewGraph(Mgr->shouldTrimGraph());
476
477  // Display warnings.
478  Eng.getBugReporter().FlushReports();
479}
480
481void AnalysisConsumer::RunPathSensitiveChecks(Decl *D, SetOfDecls *Visited) {
482
483  switch (Mgr->getLangOpts().getGC()) {
484  case LangOptions::NonGC:
485    ActionExprEngine(D, false, Visited);
486    break;
487
488  case LangOptions::GCOnly:
489    ActionExprEngine(D, true, Visited);
490    break;
491
492  case LangOptions::HybridGC:
493    ActionExprEngine(D, false, Visited);
494    ActionExprEngine(D, true, Visited);
495    break;
496  }
497}
498
499//===----------------------------------------------------------------------===//
500// AnalysisConsumer creation.
501//===----------------------------------------------------------------------===//
502
503ASTConsumer* ento::CreateAnalysisConsumer(const Preprocessor& pp,
504                                          const std::string& outDir,
505                                          const AnalyzerOptions& opts,
506                                          ArrayRef<std::string> plugins) {
507  // Disable the effects of '-Werror' when using the AnalysisConsumer.
508  pp.getDiagnostics().setWarningsAsErrors(false);
509
510  return new AnalysisConsumer(pp, outDir, opts, plugins);
511}
512
513//===----------------------------------------------------------------------===//
514// Ubigraph Visualization.  FIXME: Move to separate file.
515//===----------------------------------------------------------------------===//
516
517namespace {
518
519class UbigraphViz : public ExplodedNode::Auditor {
520  OwningPtr<raw_ostream> Out;
521  llvm::sys::Path Dir, Filename;
522  unsigned Cntr;
523
524  typedef llvm::DenseMap<void*,unsigned> VMap;
525  VMap M;
526
527public:
528  UbigraphViz(raw_ostream *out, llvm::sys::Path& dir,
529              llvm::sys::Path& filename);
530
531  ~UbigraphViz();
532
533  virtual void AddEdge(ExplodedNode *Src, ExplodedNode *Dst);
534};
535
536} // end anonymous namespace
537
538static ExplodedNode::Auditor* CreateUbiViz() {
539  std::string ErrMsg;
540
541  llvm::sys::Path Dir = llvm::sys::Path::GetTemporaryDirectory(&ErrMsg);
542  if (!ErrMsg.empty())
543    return 0;
544
545  llvm::sys::Path Filename = Dir;
546  Filename.appendComponent("llvm_ubi");
547  Filename.makeUnique(true,&ErrMsg);
548
549  if (!ErrMsg.empty())
550    return 0;
551
552  llvm::errs() << "Writing '" << Filename.str() << "'.\n";
553
554  OwningPtr<llvm::raw_fd_ostream> Stream;
555  Stream.reset(new llvm::raw_fd_ostream(Filename.c_str(), ErrMsg));
556
557  if (!ErrMsg.empty())
558    return 0;
559
560  return new UbigraphViz(Stream.take(), Dir, Filename);
561}
562
563void UbigraphViz::AddEdge(ExplodedNode *Src, ExplodedNode *Dst) {
564
565  assert (Src != Dst && "Self-edges are not allowed.");
566
567  // Lookup the Src.  If it is a new node, it's a root.
568  VMap::iterator SrcI= M.find(Src);
569  unsigned SrcID;
570
571  if (SrcI == M.end()) {
572    M[Src] = SrcID = Cntr++;
573    *Out << "('vertex', " << SrcID << ", ('color','#00ff00'))\n";
574  }
575  else
576    SrcID = SrcI->second;
577
578  // Lookup the Dst.
579  VMap::iterator DstI= M.find(Dst);
580  unsigned DstID;
581
582  if (DstI == M.end()) {
583    M[Dst] = DstID = Cntr++;
584    *Out << "('vertex', " << DstID << ")\n";
585  }
586  else {
587    // We have hit DstID before.  Change its style to reflect a cache hit.
588    DstID = DstI->second;
589    *Out << "('change_vertex_style', " << DstID << ", 1)\n";
590  }
591
592  // Add the edge.
593  *Out << "('edge', " << SrcID << ", " << DstID
594       << ", ('arrow','true'), ('oriented', 'true'))\n";
595}
596
597UbigraphViz::UbigraphViz(raw_ostream *out, llvm::sys::Path& dir,
598                         llvm::sys::Path& filename)
599  : Out(out), Dir(dir), Filename(filename), Cntr(0) {
600
601  *Out << "('vertex_style_attribute', 0, ('shape', 'icosahedron'))\n";
602  *Out << "('vertex_style', 1, 0, ('shape', 'sphere'), ('color', '#ffcc66'),"
603          " ('size', '1.5'))\n";
604}
605
606UbigraphViz::~UbigraphViz() {
607  Out.reset(0);
608  llvm::errs() << "Running 'ubiviz' program... ";
609  std::string ErrMsg;
610  llvm::sys::Path Ubiviz = llvm::sys::Program::FindProgramByName("ubiviz");
611  std::vector<const char*> args;
612  args.push_back(Ubiviz.c_str());
613  args.push_back(Filename.c_str());
614  args.push_back(0);
615
616  if (llvm::sys::Program::ExecuteAndWait(Ubiviz, &args[0],0,0,0,0,&ErrMsg)) {
617    llvm::errs() << "Error viewing graph: " << ErrMsg << "\n";
618  }
619
620  // Delete the directory.
621  Dir.eraseFromDisk(true);
622}
623