llvm-project/clang/tools/clang-cc/AnalysisConsumer.cpp

772 lines
23 KiB
C++

//===--- AnalysisConsumer.cpp - ASTConsumer for running Analyses ----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// "Meta" ASTConsumer for running different source analyses.
//
//===----------------------------------------------------------------------===//
#include "ASTConsumers.h"
#include "clang/Frontend/PathDiagnosticClients.h"
#include "clang/Frontend/ManagerRegistry.h"
#include "clang/AST/ASTConsumer.h"
#include "clang/AST/Decl.h"
#include "clang/AST/DeclObjC.h"
#include "llvm/Support/Compiler.h"
#include "llvm/ADT/OwningPtr.h"
#include "clang/AST/CFG.h"
#include "clang/Analysis/Analyses/LiveVariables.h"
#include "clang/Analysis/PathDiagnostic.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Basic/FileManager.h"
#include "clang/AST/ParentMap.h"
#include "clang/Analysis/PathSensitive/BugReporter.h"
#include "clang/Analysis/Analyses/LiveVariables.h"
#include "clang/Analysis/LocalCheckers.h"
#include "clang/Analysis/PathSensitive/GRTransferFuncs.h"
#include "clang/Analysis/PathSensitive/GRExprEngine.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Streams.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/System/Path.h"
#include "llvm/System/Program.h"
using namespace clang;
static ExplodedNodeImpl::Auditor* CreateUbiViz();
//===----------------------------------------------------------------------===//
// Analyzer Options: available analyses.
//===----------------------------------------------------------------------===//
/// Analysis - Set of available source code analyses.
enum Analyses {
#define ANALYSIS(NAME, CMDFLAG, DESC, SCOPE) NAME,
#include "Analyses.def"
NumAnalyses
};
static llvm::cl::list<Analyses>
AnalysisList(llvm::cl::desc("Source Code Analysis - Checks and Analyses"),
llvm::cl::values(
#define ANALYSIS(NAME, CMDFLAG, DESC, SCOPE)\
clEnumValN(NAME, CMDFLAG, DESC),
#include "Analyses.def"
clEnumValEnd));
//===----------------------------------------------------------------------===//
// Analyzer Options: store model.
//===----------------------------------------------------------------------===//
/// AnalysisStores - Set of available analysis store models.
enum AnalysisStores {
#define ANALYSIS_STORE(NAME, CMDFLAG, DESC, CREATFN) NAME##Model,
#include "Analyses.def"
NumStores
};
static llvm::cl::opt<AnalysisStores>
AnalysisStoreOpt("analyzer-store",
llvm::cl::desc("Source Code Analysis - Abstract Memory Store Models"),
llvm::cl::init(BasicStoreModel),
llvm::cl::values(
#define ANALYSIS_STORE(NAME, CMDFLAG, DESC, CREATFN)\
clEnumValN(NAME##Model, CMDFLAG, DESC),
#include "Analyses.def"
clEnumValEnd));
//===----------------------------------------------------------------------===//
// Analyzer Options: constraint engines.
//===----------------------------------------------------------------------===//
/// AnalysisConstraints - Set of available constraint models.
enum AnalysisConstraints {
#define ANALYSIS_CONSTRAINTS(NAME, CMDFLAG, DESC, CREATFN) NAME##Model,
#include "Analyses.def"
NumConstraints
};
static llvm::cl::opt<AnalysisConstraints>
AnalysisConstraintsOpt("analyzer-constraints",
llvm::cl::desc("Source Code Analysis - Symbolic Constraint Engines"),
llvm::cl::init(RangeConstraintsModel),
llvm::cl::values(
#define ANALYSIS_CONSTRAINTS(NAME, CMDFLAG, DESC, CREATFN)\
clEnumValN(NAME##Model, CMDFLAG, DESC),
#include "Analyses.def"
clEnumValEnd));
//===----------------------------------------------------------------------===//
// Analyzer Options: diagnostic clients.
//===----------------------------------------------------------------------===//
/// AnalysisDiagClients - Set of available diagnostic clients for rendering
/// analysis results.
enum AnalysisDiagClients {
#define ANALYSIS_DIAGNOSTICS(NAME, CMDFLAG, DESC, CREATFN, AUTOCREAT) PD_##NAME,
#include "Analyses.def"
NUM_ANALYSIS_DIAG_CLIENTS
};
static llvm::cl::opt<AnalysisDiagClients>
AnalysisDiagOpt("analyzer-output",
llvm::cl::desc("Source Code Analysis - Output Options"),
llvm::cl::init(PD_HTML),
llvm::cl::values(
#define ANALYSIS_DIAGNOSTICS(NAME, CMDFLAG, DESC, CREATFN, AUTOCREATE)\
clEnumValN(PD_##NAME, CMDFLAG, DESC),
#include "Analyses.def"
clEnumValEnd));
//===----------------------------------------------------------------------===//
// Misc. fun options.
//===----------------------------------------------------------------------===//
static llvm::cl::opt<bool>
VisualizeEGDot("analyzer-viz-egraph-graphviz",
llvm::cl::desc("Display exploded graph using GraphViz"));
static llvm::cl::opt<bool>
VisualizeEGUbi("analyzer-viz-egraph-ubigraph",
llvm::cl::desc("Display exploded graph using Ubigraph"));
static llvm::cl::opt<bool>
AnalyzeAll("analyzer-opt-analyze-headers",
llvm::cl::desc("Force the static analyzer to analyze "
"functions defined in header files"));
static llvm::cl::opt<bool>
AnalyzerDisplayProgress("analyzer-display-progress",
llvm::cl::desc("Emit verbose output about the analyzer's progress."));
static llvm::cl::opt<bool>
PurgeDead("analyzer-purge-dead",
llvm::cl::init(true),
llvm::cl::desc("Remove dead symbols, bindings, and constraints before"
" processing a statement."));
static llvm::cl::opt<bool>
EagerlyAssume("analyzer-eagerly-assume",
llvm::cl::init(false),
llvm::cl::desc("Eagerly assume the truth/falseness of some "
"symbolic constraints."));
static llvm::cl::opt<std::string>
AnalyzeSpecificFunction("analyze-function",
llvm::cl::desc("Run analysis on specific function"));
static llvm::cl::opt<bool>
TrimGraph("trim-egraph",
llvm::cl::desc("Only show error-related paths in the analysis graph"));
//===----------------------------------------------------------------------===//
// Basic type definitions.
//===----------------------------------------------------------------------===//
namespace {
class AnalysisManager;
typedef void (*CodeAction)(AnalysisManager& Mgr);
} // end anonymous namespace
//===----------------------------------------------------------------------===//
// AnalysisConsumer declaration.
//===----------------------------------------------------------------------===//
namespace {
class VISIBILITY_HIDDEN AnalysisConsumer : public ASTConsumer {
typedef std::vector<CodeAction> Actions;
Actions FunctionActions;
Actions ObjCMethodActions;
Actions ObjCImplementationActions;
Actions TranslationUnitActions;
public:
const LangOptions& LOpts;
Diagnostic &Diags;
ASTContext* Ctx;
Preprocessor* PP;
PreprocessorFactory* PPF;
const std::string OutDir;
llvm::OwningPtr<PathDiagnosticClient> PD;
AnalysisConsumer(Diagnostic &diags, Preprocessor* pp,
PreprocessorFactory* ppf,
const LangOptions& lopts,
const std::string& outdir)
: LOpts(lopts), Diags(diags),
Ctx(0), PP(pp), PPF(ppf),
OutDir(outdir) {}
void addCodeAction(CodeAction action) {
FunctionActions.push_back(action);
ObjCMethodActions.push_back(action);
}
void addObjCImplementationAction(CodeAction action) {
ObjCImplementationActions.push_back(action);
}
void addTranslationUnitAction(CodeAction action) {
TranslationUnitActions.push_back(action);
}
virtual void Initialize(ASTContext &Context) {
Ctx = &Context;
}
virtual void HandleTopLevelDecl(DeclGroupRef D) {
for (DeclGroupRef::iterator I = D.begin(), E = D.end(); I != E; ++I)
HandleTopLevelSingleDecl(*I);
}
void HandleTopLevelSingleDecl(Decl *D);
virtual void HandleTranslationUnit(ASTContext &C);
void HandleCode(Decl* D, Stmt* Body, Actions& actions);
};
class VISIBILITY_HIDDEN AnalysisManager : public BugReporterData {
Decl* D; Stmt* Body;
enum AnalysisScope { ScopeTU, ScopeDecl } AScope;
AnalysisConsumer& C;
bool DisplayedFunction;
llvm::OwningPtr<CFG> cfg;
llvm::OwningPtr<LiveVariables> liveness;
llvm::OwningPtr<ParentMap> PM;
// Configurable components creators.
StoreManagerCreator CreateStoreMgr;
ConstraintManagerCreator CreateConstraintMgr;
public:
AnalysisManager(AnalysisConsumer& c, Decl* d, Stmt* b, bool displayProgress)
: D(d), Body(b), AScope(ScopeDecl), C(c),
DisplayedFunction(!displayProgress) {
setManagerCreators();
}
AnalysisManager(AnalysisConsumer& c, bool displayProgress)
: D(0), Body(0), AScope(ScopeTU), C(c),
DisplayedFunction(!displayProgress) {
setManagerCreators();
}
Decl* getCodeDecl() const {
assert (AScope == ScopeDecl);
return D;
}
Stmt* getBody() const {
assert (AScope == ScopeDecl);
return Body;
}
StoreManagerCreator getStoreManagerCreator() {
return CreateStoreMgr;
};
ConstraintManagerCreator getConstraintManagerCreator() {
return CreateConstraintMgr;
}
virtual CFG* getCFG() {
if (!cfg) cfg.reset(CFG::buildCFG(getBody()));
return cfg.get();
}
virtual ParentMap& getParentMap() {
if (!PM)
PM.reset(new ParentMap(getBody()));
return *PM.get();
}
virtual ASTContext& getContext() {
return *C.Ctx;
}
virtual SourceManager& getSourceManager() {
return getContext().getSourceManager();
}
virtual Diagnostic& getDiagnostic() {
return C.Diags;
}
const LangOptions& getLangOptions() const {
return C.LOpts;
}
virtual PathDiagnosticClient* getPathDiagnosticClient() {
if (C.PD.get() == 0 && !C.OutDir.empty()) {
switch (AnalysisDiagOpt) {
default:
#define ANALYSIS_DIAGNOSTICS(NAME, CMDFLAG, DESC, CREATEFN, AUTOCREATE)\
case PD_##NAME: C.PD.reset(CREATEFN(C.OutDir, C.PP, C.PPF)); break;
#include "Analyses.def"
}
}
return C.PD.get();
}
virtual LiveVariables* getLiveVariables() {
if (!liveness) {
CFG* c = getCFG();
if (!c) return 0;
liveness.reset(new LiveVariables(getContext(), *c));
liveness->runOnCFG(*c);
liveness->runOnAllBlocks(*c, 0, true);
}
return liveness.get();
}
bool shouldVisualizeGraphviz() const { return VisualizeEGDot; }
bool shouldVisualizeUbigraph() const { return VisualizeEGUbi; }
bool shouldVisualize() const {
return VisualizeEGDot || VisualizeEGUbi;
}
bool shouldTrimGraph() const { return TrimGraph; }
void DisplayFunction() {
if (DisplayedFunction)
return;
DisplayedFunction = true;
// FIXME: Is getCodeDecl() always a named decl?
if (isa<FunctionDecl>(getCodeDecl()) ||
isa<ObjCMethodDecl>(getCodeDecl())) {
NamedDecl *ND = cast<NamedDecl>(getCodeDecl());
SourceManager &SM = getContext().getSourceManager();
llvm::cerr << "ANALYZE: "
<< SM.getPresumedLoc(ND->getLocation()).getFilename()
<< ' ' << ND->getNameAsString() << '\n';
}
}
private:
/// Set configurable analyzer components creators. First check if there are
/// components registered at runtime. Otherwise fall back to builtin
/// components.
void setManagerCreators() {
if (ManagerRegistry::StoreMgrCreator != 0) {
CreateStoreMgr = ManagerRegistry::StoreMgrCreator;
}
else {
switch (AnalysisStoreOpt) {
default:
assert(0 && "Unknown store manager.");
#define ANALYSIS_STORE(NAME, CMDFLAG, DESC, CREATEFN) \
case NAME##Model: CreateStoreMgr = CREATEFN; break;
#include "Analyses.def"
}
}
if (ManagerRegistry::ConstraintMgrCreator != 0)
CreateConstraintMgr = ManagerRegistry::ConstraintMgrCreator;
else {
switch (AnalysisConstraintsOpt) {
default:
assert(0 && "Unknown store manager.");
#define ANALYSIS_CONSTRAINTS(NAME, CMDFLAG, DESC, CREATEFN) \
case NAME##Model: CreateConstraintMgr = CREATEFN; break;
#include "Analyses.def"
}
}
// Some DiagnosticClients should be created all the time instead of
// lazily. Create those now.
switch (AnalysisDiagOpt) {
default: break;
#define ANALYSIS_DIAGNOSTICS(NAME, CMDFLAG, DESC, CREATEFN, AUTOCREATE)\
case PD_##NAME: if (AUTOCREATE) getPathDiagnosticClient(); break;
#include "Analyses.def"
}
}
};
} // end anonymous namespace
namespace llvm {
template <> struct FoldingSetTrait<CodeAction> {
static inline void Profile(CodeAction X, FoldingSetNodeID& ID) {
ID.AddPointer(reinterpret_cast<void*>(reinterpret_cast<uintptr_t>(X)));
}
};
}
//===----------------------------------------------------------------------===//
// AnalysisConsumer implementation.
//===----------------------------------------------------------------------===//
void AnalysisConsumer::HandleTopLevelSingleDecl(Decl *D) {
switch (D->getKind()) {
case Decl::Function: {
FunctionDecl* FD = cast<FunctionDecl>(D);
if (AnalyzeSpecificFunction.size() > 0 &&
AnalyzeSpecificFunction != FD->getIdentifier()->getName())
break;
Stmt* Body = FD->getBody(*Ctx);
if (Body) HandleCode(FD, Body, FunctionActions);
break;
}
case Decl::ObjCMethod: {
ObjCMethodDecl* MD = cast<ObjCMethodDecl>(D);
if (AnalyzeSpecificFunction.size() > 0 &&
AnalyzeSpecificFunction != MD->getSelector().getAsString())
return;
Stmt* Body = MD->getBody();
if (Body) HandleCode(MD, Body, ObjCMethodActions);
break;
}
default:
break;
}
}
void AnalysisConsumer::HandleTranslationUnit(ASTContext &C) {
if(!TranslationUnitActions.empty()) {
AnalysisManager mgr(*this, AnalyzerDisplayProgress);
for (Actions::iterator I = TranslationUnitActions.begin(),
E = TranslationUnitActions.end(); I != E; ++I)
(*I)(mgr);
}
if (!ObjCImplementationActions.empty()) {
TranslationUnitDecl *TUD = C.getTranslationUnitDecl();
for (DeclContext::decl_iterator I = TUD->decls_begin(C),
E = TUD->decls_end(C);
I != E; ++I)
if (ObjCImplementationDecl* ID = dyn_cast<ObjCImplementationDecl>(*I))
HandleCode(ID, 0, ObjCImplementationActions);
}
// Delete the PathDiagnosticClient here just in case the AnalysisConsumer
// object doesn't get released. This will cause any side-effects in the
// destructor of the PathDiagnosticClient to get executed.
PD.reset();
}
void AnalysisConsumer::HandleCode(Decl* D, Stmt* Body, Actions& actions) {
// Don't run the actions if an error has occured with parsing the file.
if (Diags.hasErrorOccurred())
return;
// Don't run the actions on declarations in header files unless
// otherwise specified.
if (!AnalyzeAll && !Ctx->getSourceManager().isFromMainFile(D->getLocation()))
return;
// Create an AnalysisManager that will manage the state for analyzing
// this method/function.
AnalysisManager mgr(*this, D, Body, AnalyzerDisplayProgress);
// Dispatch on the actions.
for (Actions::iterator I = actions.begin(), E = actions.end(); I != E; ++I)
(*I)(mgr);
}
//===----------------------------------------------------------------------===//
// Analyses
//===----------------------------------------------------------------------===//
static void ActionWarnDeadStores(AnalysisManager& mgr) {
if (LiveVariables* L = mgr.getLiveVariables()) {
BugReporter BR(mgr);
CheckDeadStores(*L, BR);
}
}
static void ActionWarnUninitVals(AnalysisManager& mgr) {
if (CFG* c = mgr.getCFG())
CheckUninitializedValues(*c, mgr.getContext(), mgr.getDiagnostic());
}
static void ActionGRExprEngine(AnalysisManager& mgr, GRTransferFuncs* tf,
bool StandardWarnings = true) {
llvm::OwningPtr<GRTransferFuncs> TF(tf);
// Display progress.
mgr.DisplayFunction();
// Construct the analysis engine.
LiveVariables* L = mgr.getLiveVariables();
if (!L) return;
GRExprEngine Eng(*mgr.getCFG(), *mgr.getCodeDecl(), mgr.getContext(), *L, mgr,
PurgeDead, EagerlyAssume,
mgr.getStoreManagerCreator(),
mgr.getConstraintManagerCreator());
Eng.setTransferFunctions(tf);
if (StandardWarnings) {
Eng.RegisterInternalChecks();
RegisterAppleChecks(Eng);
}
// Set the graph auditor.
llvm::OwningPtr<ExplodedNodeImpl::Auditor> Auditor;
if (mgr.shouldVisualizeUbigraph()) {
Auditor.reset(CreateUbiViz());
ExplodedNodeImpl::SetAuditor(Auditor.get());
}
// Execute the worklist algorithm.
Eng.ExecuteWorkList();
// Release the auditor (if any) so that it doesn't monitor the graph
// created BugReporter.
ExplodedNodeImpl::SetAuditor(0);
// Visualize the exploded graph.
if (mgr.shouldVisualizeGraphviz())
Eng.ViewGraph(mgr.shouldTrimGraph());
// Display warnings.
Eng.getBugReporter().FlushReports();
}
static void ActionCheckerCFRefAux(AnalysisManager& mgr, bool GCEnabled,
bool StandardWarnings) {
GRTransferFuncs* TF = MakeCFRefCountTF(mgr.getContext(),
GCEnabled,
mgr.getLangOptions());
ActionGRExprEngine(mgr, TF, StandardWarnings);
}
static void ActionCheckerCFRef(AnalysisManager& mgr) {
switch (mgr.getLangOptions().getGCMode()) {
default:
assert (false && "Invalid GC mode.");
case LangOptions::NonGC:
ActionCheckerCFRefAux(mgr, false, true);
break;
case LangOptions::GCOnly:
ActionCheckerCFRefAux(mgr, true, true);
break;
case LangOptions::HybridGC:
ActionCheckerCFRefAux(mgr, false, true);
ActionCheckerCFRefAux(mgr, true, false);
break;
}
}
static void ActionCheckerSimple(AnalysisManager& mgr) {
ActionGRExprEngine(mgr, MakeGRSimpleValsTF());
}
static void ActionDisplayLiveVariables(AnalysisManager& mgr) {
if (LiveVariables* L = mgr.getLiveVariables()) {
mgr.DisplayFunction();
L->dumpBlockLiveness(mgr.getSourceManager());
}
}
static void ActionCFGDump(AnalysisManager& mgr) {
if (CFG* c = mgr.getCFG()) {
mgr.DisplayFunction();
c->dump();
}
}
static void ActionCFGView(AnalysisManager& mgr) {
if (CFG* c = mgr.getCFG()) {
mgr.DisplayFunction();
c->viewCFG();
}
}
static void ActionWarnObjCDealloc(AnalysisManager& mgr) {
if (mgr.getLangOptions().getGCMode() == LangOptions::GCOnly)
return;
BugReporter BR(mgr);
CheckObjCDealloc(cast<ObjCImplementationDecl>(mgr.getCodeDecl()),
mgr.getLangOptions(), BR);
}
static void ActionWarnObjCUnusedIvars(AnalysisManager& mgr) {
BugReporter BR(mgr);
CheckObjCUnusedIvar(cast<ObjCImplementationDecl>(mgr.getCodeDecl()), BR);
}
static void ActionWarnObjCMethSigs(AnalysisManager& mgr) {
BugReporter BR(mgr);
CheckObjCInstMethSignature(cast<ObjCImplementationDecl>(mgr.getCodeDecl()),
BR);
}
//===----------------------------------------------------------------------===//
// AnalysisConsumer creation.
//===----------------------------------------------------------------------===//
ASTConsumer* clang::CreateAnalysisConsumer(Diagnostic &diags, Preprocessor* pp,
PreprocessorFactory* ppf,
const LangOptions& lopts,
const std::string& OutDir) {
llvm::OwningPtr<AnalysisConsumer> C(new AnalysisConsumer(diags, pp, ppf,
lopts, OutDir));
for (unsigned i = 0; i < AnalysisList.size(); ++i)
switch (AnalysisList[i]) {
#define ANALYSIS(NAME, CMD, DESC, SCOPE)\
case NAME:\
C->add ## SCOPE ## Action(&Action ## NAME);\
break;
#include "Analyses.def"
default: break;
}
return C.take();
}
//===----------------------------------------------------------------------===//
// Ubigraph Visualization. FIXME: Move to separate file.
//===----------------------------------------------------------------------===//
namespace {
class UbigraphViz : public ExplodedNodeImpl::Auditor {
llvm::OwningPtr<llvm::raw_ostream> Out;
llvm::sys::Path Dir, Filename;
unsigned Cntr;
typedef llvm::DenseMap<void*,unsigned> VMap;
VMap M;
public:
UbigraphViz(llvm::raw_ostream* out, llvm::sys::Path& dir,
llvm::sys::Path& filename);
~UbigraphViz();
virtual void AddEdge(ExplodedNodeImpl* Src, ExplodedNodeImpl* Dst);
};
} // end anonymous namespace
static ExplodedNodeImpl::Auditor* CreateUbiViz() {
std::string ErrMsg;
llvm::sys::Path Dir = llvm::sys::Path::GetTemporaryDirectory(&ErrMsg);
if (!ErrMsg.empty())
return 0;
llvm::sys::Path Filename = Dir;
Filename.appendComponent("llvm_ubi");
Filename.makeUnique(true,&ErrMsg);
if (!ErrMsg.empty())
return 0;
llvm::cerr << "Writing '" << Filename << "'.\n";
llvm::OwningPtr<llvm::raw_fd_ostream> Stream;
std::string filename = Filename.toString();
Stream.reset(new llvm::raw_fd_ostream(filename.c_str(), false, ErrMsg));
if (!ErrMsg.empty())
return 0;
return new UbigraphViz(Stream.take(), Dir, Filename);
}
void UbigraphViz::AddEdge(ExplodedNodeImpl* Src, ExplodedNodeImpl* Dst) {
assert (Src != Dst && "Self-edges are not allowed.");
// Lookup the Src. If it is a new node, it's a root.
VMap::iterator SrcI= M.find(Src);
unsigned SrcID;
if (SrcI == M.end()) {
M[Src] = SrcID = Cntr++;
*Out << "('vertex', " << SrcID << ", ('color','#00ff00'))\n";
}
else
SrcID = SrcI->second;
// Lookup the Dst.
VMap::iterator DstI= M.find(Dst);
unsigned DstID;
if (DstI == M.end()) {
M[Dst] = DstID = Cntr++;
*Out << "('vertex', " << DstID << ")\n";
}
else {
// We have hit DstID before. Change its style to reflect a cache hit.
DstID = DstI->second;
*Out << "('change_vertex_style', " << DstID << ", 1)\n";
}
// Add the edge.
*Out << "('edge', " << SrcID << ", " << DstID
<< ", ('arrow','true'), ('oriented', 'true'))\n";
}
UbigraphViz::UbigraphViz(llvm::raw_ostream* out, llvm::sys::Path& dir,
llvm::sys::Path& filename)
: Out(out), Dir(dir), Filename(filename), Cntr(0) {
*Out << "('vertex_style_attribute', 0, ('shape', 'icosahedron'))\n";
*Out << "('vertex_style', 1, 0, ('shape', 'sphere'), ('color', '#ffcc66'),"
" ('size', '1.5'))\n";
}
UbigraphViz::~UbigraphViz() {
Out.reset(0);
llvm::cerr << "Running 'ubiviz' program... ";
std::string ErrMsg;
llvm::sys::Path Ubiviz = llvm::sys::Program::FindProgramByName("ubiviz");
std::vector<const char*> args;
args.push_back(Ubiviz.c_str());
args.push_back(Filename.c_str());
args.push_back(0);
if (llvm::sys::Program::ExecuteAndWait(Ubiviz, &args[0],0,0,0,0,&ErrMsg)) {
llvm::cerr << "Error viewing graph: " << ErrMsg << "\n";
}
// Delete the directory.
Dir.eraseFromDisk(true);
}