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//===--- 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.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "AnalysisConsumer"
#include "AnalysisConsumer.h"
#include "clang/AST/ASTConsumer.h"
#include "clang/AST/Decl.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/ParentMap.h"
#include "clang/AST/RecursiveASTVisitor.h"
#include "clang/Analysis/CFG.h"
#include "clang/Analysis/CallGraph.h"
#include "clang/StaticAnalyzer/Frontend/CheckerRegistration.h"
#include "clang/StaticAnalyzer/Core/CheckerManager.h"
#include "clang/StaticAnalyzer/Checkers/LocalCheckers.h"
#include "clang/StaticAnalyzer/Core/BugReporter/PathDiagnostic.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
#include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
#include "clang/StaticAnalyzer/Core/PathDiagnosticConsumers.h"
#include "clang/Basic/FileManager.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Frontend/AnalyzerOptions.h"
#include "clang/Lex/Preprocessor.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/Program.h"
#include "llvm/Support/Timer.h"
#include "llvm/ADT/DepthFirstIterator.h"
#include "llvm/ADT/OwningPtr.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/Statistic.h"
#include <queue>
using namespace clang;
using namespace ento;
using llvm::SmallPtrSet;
static ExplodedNode::Auditor* CreateUbiViz();
STATISTIC(NumFunctionTopLevel, "The # of functions at top level.");
STATISTIC(NumFunctionsAnalyzed, "The # of functions analysed (as top level).");
STATISTIC(NumBlocksInAnalyzedFunctions,
"The # of basic blocks in the analyzed functions.");
STATISTIC(PercentReachableBlocks, "The % of reachable basic blocks.");
//===----------------------------------------------------------------------===//
// Special PathDiagnosticConsumers.
//===----------------------------------------------------------------------===//
static PathDiagnosticConsumer*
createPlistHTMLDiagnosticConsumer(const std::string& prefix,
const Preprocessor &PP) {
PathDiagnosticConsumer *PD =
createHTMLDiagnosticConsumer(llvm::sys::path::parent_path(prefix), PP);
return createPlistDiagnosticConsumer(prefix, PP, PD);
}
//===----------------------------------------------------------------------===//
// AnalysisConsumer declaration.
//===----------------------------------------------------------------------===//
namespace {
class AnalysisConsumer : public ASTConsumer,
public RecursiveASTVisitor<AnalysisConsumer> {
enum AnalysisMode {
ANALYSIS_SYNTAX,
ANALYSIS_PATH,
ANALYSIS_ALL
};
/// Mode of the analyzes while recursively visiting Decls.
AnalysisMode RecVisitorMode;
/// Bug Reporter to use while recursively visiting Decls.
BugReporter *RecVisitorBR;
public:
ASTContext *Ctx;
const Preprocessor &PP;
const std::string OutDir;
AnalyzerOptions Opts;
ArrayRef<std::string> Plugins;
/// \brief Stores the declarations from the local translation unit.
/// Note, we pre-compute the local declarations at parse time as an
/// optimization to make sure we do not deserialize everything from disk.
/// The local declaration to all declarations ratio might be very small when
/// working with a PCH file.
SetOfDecls LocalTUDecls;
// PD is owned by AnalysisManager.
PathDiagnosticConsumer *PD;
StoreManagerCreator CreateStoreMgr;
ConstraintManagerCreator CreateConstraintMgr;
OwningPtr<CheckerManager> checkerMgr;
OwningPtr<AnalysisManager> Mgr;
/// Time the analyzes time of each translation unit.
static llvm::Timer* TUTotalTimer;
/// The information about analyzed functions shared throughout the
/// translation unit.
FunctionSummariesTy FunctionSummaries;
AnalysisConsumer(const Preprocessor& pp,
const std::string& outdir,
const AnalyzerOptions& opts,
ArrayRef<std::string> plugins)
: RecVisitorMode(ANALYSIS_ALL), RecVisitorBR(0),
Ctx(0), PP(pp), OutDir(outdir), Opts(opts), Plugins(plugins), PD(0) {
DigestAnalyzerOptions();
if (Opts.PrintStats) {
llvm::EnableStatistics();
TUTotalTimer = new llvm::Timer("Analyzer Total Time");
}
}
~AnalysisConsumer() {
if (Opts.PrintStats)
delete TUTotalTimer;
}
void DigestAnalyzerOptions() {
// Create the PathDiagnosticConsumer.
if (!OutDir.empty()) {
switch (Opts.AnalysisDiagOpt) {
default:
#define ANALYSIS_DIAGNOSTICS(NAME, CMDFLAG, DESC, CREATEFN, AUTOCREATE) \
case PD_##NAME: PD = CREATEFN(OutDir, PP); break;
#include "clang/Frontend/Analyses.def"
}
} else if (Opts.AnalysisDiagOpt == PD_TEXT) {
// Create the text client even without a specified output file since
// it just uses diagnostic notes.
PD = createTextPathDiagnosticConsumer("", PP);
}
// Create the analyzer component creators.
switch (Opts.AnalysisStoreOpt) {
default:
llvm_unreachable("Unknown store manager.");
#define ANALYSIS_STORE(NAME, CMDFLAG, DESC, CREATEFN) \
case NAME##Model: CreateStoreMgr = CREATEFN; break;
#include "clang/Frontend/Analyses.def"
}
switch (Opts.AnalysisConstraintsOpt) {
default:
llvm_unreachable("Unknown store manager.");
#define ANALYSIS_CONSTRAINTS(NAME, CMDFLAG, DESC, CREATEFN) \
case NAME##Model: CreateConstraintMgr = CREATEFN; break;
#include "clang/Frontend/Analyses.def"
}
}
void DisplayFunction(const Decl *D, AnalysisMode Mode) {
if (!Opts.AnalyzerDisplayProgress)
return;
SourceManager &SM = Mgr->getASTContext().getSourceManager();
PresumedLoc Loc = SM.getPresumedLoc(D->getLocation());
if (Loc.isValid()) {
llvm::errs() << "ANALYZE";
switch (Mode) {
case ANALYSIS_SYNTAX: llvm::errs() << "(Syntax)"; break;
case ANALYSIS_PATH: llvm::errs() << "(Path Sensitive)"; break;
case ANALYSIS_ALL: break;
};
llvm::errs() << ": " << Loc.getFilename();
if (isa<FunctionDecl>(D) || isa<ObjCMethodDecl>(D)) {
const NamedDecl *ND = cast<NamedDecl>(D);
llvm::errs() << ' ' << *ND << '\n';
}
else if (isa<BlockDecl>(D)) {
llvm::errs() << ' ' << "block(line:" << Loc.getLine() << ",col:"
<< Loc.getColumn() << '\n';
}
else if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
Selector S = MD->getSelector();
llvm::errs() << ' ' << S.getAsString();
}
}
}
virtual void Initialize(ASTContext &Context) {
Ctx = &Context;
checkerMgr.reset(createCheckerManager(Opts, PP.getLangOpts(), Plugins,
PP.getDiagnostics()));
Mgr.reset(new AnalysisManager(*Ctx, PP.getDiagnostics(),
PP.getLangOpts(), PD,
CreateStoreMgr, CreateConstraintMgr,
checkerMgr.get(),
Opts.MaxNodes, Opts.MaxLoop,
Opts.VisualizeEGDot, Opts.VisualizeEGUbi,
Opts.AnalysisPurgeOpt, Opts.EagerlyAssume,
Opts.TrimGraph,
Opts.UnoptimizedCFG, Opts.CFGAddImplicitDtors,
Opts.CFGAddInitializers,
Opts.EagerlyTrimEGraph,
Opts.IPAMode,
Opts.InlineMaxStackDepth,
Opts.InlineMaxFunctionSize,
Opts.InliningMode,
Opts.NoRetryExhausted));
}
/// \brief Store the top level decls in the set to be processed later on.
/// (Doing this pre-processing avoids deserialization of data from PCH.)
virtual bool HandleTopLevelDecl(DeclGroupRef D);
virtual void HandleTopLevelDeclInObjCContainer(DeclGroupRef D);
virtual void HandleTranslationUnit(ASTContext &C);
/// \brief Build the call graph for all the top level decls of this TU and
/// use it to define the order in which the functions should be visited.
void HandleDeclsGallGraph();
/// \brief Run analyzes(syntax or path sensitive) on the given function.
/// \param Mode - determines if we are requesting syntax only or path
/// sensitive only analysis.
/// \param VisitedCallees - The output parameter, which is populated with the
/// set of functions which should be considered analyzed after analyzing the
/// given root function.
void HandleCode(Decl *D, AnalysisMode Mode,
SetOfConstDecls *VisitedCallees = 0);
void RunPathSensitiveChecks(Decl *D, SetOfConstDecls *VisitedCallees);
void ActionExprEngine(Decl *D, bool ObjCGCEnabled,
SetOfConstDecls *VisitedCallees);
/// Visitors for the RecursiveASTVisitor.
/// Handle callbacks for arbitrary Decls.
bool VisitDecl(Decl *D) {
checkerMgr->runCheckersOnASTDecl(D, *Mgr, *RecVisitorBR);
return true;
}
bool VisitFunctionDecl(FunctionDecl *FD) {
IdentifierInfo *II = FD->getIdentifier();
if (II && II->getName().startswith("__inline"))
return true;
// We skip function template definitions, as their semantics is
// only determined when they are instantiated.
if (FD->isThisDeclarationADefinition() &&
!FD->isDependentContext()) {
HandleCode(FD, RecVisitorMode);
}
return true;
}
bool VisitObjCMethodDecl(ObjCMethodDecl *MD) {
checkerMgr->runCheckersOnASTDecl(MD, *Mgr, *RecVisitorBR);
if (MD->isThisDeclarationADefinition())
HandleCode(MD, RecVisitorMode);
return true;
}
private:
void storeTopLevelDecls(DeclGroupRef DG);
/// \brief Check if we should skip (not analyze) the given function.
bool skipFunction(Decl *D);
};
} // end anonymous namespace
//===----------------------------------------------------------------------===//
// AnalysisConsumer implementation.
//===----------------------------------------------------------------------===//
llvm::Timer* AnalysisConsumer::TUTotalTimer = 0;
bool AnalysisConsumer::HandleTopLevelDecl(DeclGroupRef DG) {
storeTopLevelDecls(DG);
return true;
}
void AnalysisConsumer::HandleTopLevelDeclInObjCContainer(DeclGroupRef DG) {
storeTopLevelDecls(DG);
}
void AnalysisConsumer::storeTopLevelDecls(DeclGroupRef DG) {
for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I) {
// Skip ObjCMethodDecl, wait for the objc container to avoid
// analyzing twice.
if (isa<ObjCMethodDecl>(*I))
continue;
LocalTUDecls.insert(*I);
}
}
void AnalysisConsumer::HandleDeclsGallGraph() {
// Otherwise, use the Callgraph to derive the order.
// Build the Call Graph.
CallGraph CG;
// Add all the top level declarations to the graph.
for (SetOfDecls::iterator I = LocalTUDecls.begin(),
E = LocalTUDecls.end(); I != E; ++I)
CG.addToCallGraph(*I);
// Find the top level nodes - children of root + the unreachable (parentless)
// nodes.
llvm::SmallVector<CallGraphNode*, 24> TopLevelFunctions;
for (CallGraph::nodes_iterator TI = CG.parentless_begin(),
TE = CG.parentless_end(); TI != TE; ++TI) {
TopLevelFunctions.push_back(*TI);
NumFunctionTopLevel++;
}
CallGraphNode *Entry = CG.getRoot();
for (CallGraphNode::iterator I = Entry->begin(),
E = Entry->end(); I != E; ++I) {
TopLevelFunctions.push_back(*I);
NumFunctionTopLevel++;
}
// Make sure the nodes are sorted in order reverse of their definition in the
// translation unit. This step is very important for performance. It ensures
// that we analyze the root functions before the externally available
// subroutines.
std::queue<CallGraphNode*> BFSQueue;
for (llvm::SmallVector<CallGraphNode*, 24>::reverse_iterator
TI = TopLevelFunctions.rbegin(), TE = TopLevelFunctions.rend();
TI != TE; ++TI)
BFSQueue.push(*TI);
// BFS over all of the functions, while skipping the ones inlined into
// the previously processed functions. Use external Visited set, which is
// also modified when we inline a function.
SmallPtrSet<CallGraphNode*,24> Visited;
while(!BFSQueue.empty()) {
CallGraphNode *N = BFSQueue.front();
BFSQueue.pop();
// Skip the functions which have been processed already or previously
// inlined.
if (Visited.count(N))
continue;
// Analyze the function.
SetOfConstDecls VisitedCallees;
Decl *D = N->getDecl();
assert(D);
HandleCode(D, ANALYSIS_PATH,
(Mgr->InliningMode == All ? 0 : &VisitedCallees));
// Add the visited callees to the global visited set.
for (SetOfConstDecls::const_iterator I = VisitedCallees.begin(),
E = VisitedCallees.end(); I != E; ++I){
CallGraphNode *VN = CG.getNode(*I);
if (VN)
Visited.insert(VN);
}
Visited.insert(N);
// Push the children into the queue.
for (CallGraphNode::const_iterator CI = N->begin(),
CE = N->end(); CI != CE; ++CI) {
BFSQueue.push(*CI);
}
}
}
void AnalysisConsumer::HandleTranslationUnit(ASTContext &C) {
// Don't run the actions if an error has occurred with parsing the file.
DiagnosticsEngine &Diags = PP.getDiagnostics();
if (Diags.hasErrorOccurred() || Diags.hasFatalErrorOccurred())
return;
{
if (TUTotalTimer) TUTotalTimer->startTimer();
// Introduce a scope to destroy BR before Mgr.
BugReporter BR(*Mgr);
TranslationUnitDecl *TU = C.getTranslationUnitDecl();
checkerMgr->runCheckersOnASTDecl(TU, *Mgr, BR);
// Run the AST-only checks using the order in which functions are defined.
// If inlining is not turned on, use the simplest function order for path
// sensitive analyzes as well.
RecVisitorMode = (Mgr->shouldInlineCall() ? ANALYSIS_SYNTAX : ANALYSIS_ALL);
RecVisitorBR = &BR;
// Process all the top level declarations.
for (SetOfDecls::iterator I = LocalTUDecls.begin(),
E = LocalTUDecls.end(); I != E; ++I)
TraverseDecl(*I);
if (Mgr->shouldInlineCall())
HandleDeclsGallGraph();
// After all decls handled, run checkers on the entire TranslationUnit.
checkerMgr->runCheckersOnEndOfTranslationUnit(TU, *Mgr, BR);
RecVisitorBR = 0;
}
// Explicitly destroy the PathDiagnosticConsumer. This will flush its output.
// FIXME: This should be replaced with something that doesn't rely on
// side-effects in PathDiagnosticConsumer's destructor. This is required when
// used with option -disable-free.
Mgr.reset(NULL);
if (TUTotalTimer) TUTotalTimer->stopTimer();
// Count how many basic blocks we have not covered.
NumBlocksInAnalyzedFunctions = FunctionSummaries.getTotalNumBasicBlocks();
if (NumBlocksInAnalyzedFunctions > 0)
PercentReachableBlocks =
(FunctionSummaries.getTotalNumVisitedBasicBlocks() * 100) /
NumBlocksInAnalyzedFunctions;
}
static void FindBlocks(DeclContext *D, SmallVectorImpl<Decl*> &WL) {
if (BlockDecl *BD = dyn_cast<BlockDecl>(D))
WL.push_back(BD);
for (DeclContext::decl_iterator I = D->decls_begin(), E = D->decls_end();
I!=E; ++I)
if (DeclContext *DC = dyn_cast<DeclContext>(*I))
FindBlocks(DC, WL);
}
static std::string getFunctionName(const Decl *D) {
if (const ObjCMethodDecl *ID = dyn_cast<ObjCMethodDecl>(D)) {
return ID->getSelector().getAsString();
}
if (const FunctionDecl *ND = dyn_cast<FunctionDecl>(D)) {
IdentifierInfo *II = ND->getIdentifier();
if (II)
return II->getName();
}
return "";
}
bool AnalysisConsumer::skipFunction(Decl *D) {
if (!Opts.AnalyzeSpecificFunction.empty() &&
getFunctionName(D) != Opts.AnalyzeSpecificFunction)
return true;
// Don't run the actions on declarations in header files unless
// otherwise specified.
SourceManager &SM = Ctx->getSourceManager();
SourceLocation SL = SM.getExpansionLoc(D->getLocation());
if (!Opts.AnalyzeAll && !SM.isFromMainFile(SL))
return true;
return false;
}
void AnalysisConsumer::HandleCode(Decl *D, AnalysisMode Mode,
SetOfConstDecls *VisitedCallees) {
if (skipFunction(D))
return;
DisplayFunction(D, Mode);
// Clear the AnalysisManager of old AnalysisDeclContexts.
Mgr->ClearContexts();
// Dispatch on the actions.
SmallVector<Decl*, 10> WL;
WL.push_back(D);
if (D->hasBody() && Opts.AnalyzeNestedBlocks)
FindBlocks(cast<DeclContext>(D), WL);
BugReporter BR(*Mgr);
for (SmallVectorImpl<Decl*>::iterator WI=WL.begin(), WE=WL.end();
WI != WE; ++WI)
if ((*WI)->hasBody()) {
if (Mode != ANALYSIS_PATH)
checkerMgr->runCheckersOnASTBody(*WI, *Mgr, BR);
if (Mode != ANALYSIS_SYNTAX && checkerMgr->hasPathSensitiveCheckers()) {
RunPathSensitiveChecks(*WI, VisitedCallees);
NumFunctionsAnalyzed++;
}
}
}
//===----------------------------------------------------------------------===//
// Path-sensitive checking.
//===----------------------------------------------------------------------===//
void AnalysisConsumer::ActionExprEngine(Decl *D, bool ObjCGCEnabled,
SetOfConstDecls *VisitedCallees) {
// Construct the analysis engine. First check if the CFG is valid.
// FIXME: Inter-procedural analysis will need to handle invalid CFGs.
if (!Mgr->getCFG(D))
return;
ExprEngine Eng(*Mgr, ObjCGCEnabled, VisitedCallees, &FunctionSummaries);
// Set the graph auditor.
OwningPtr<ExplodedNode::Auditor> Auditor;
if (Mgr->shouldVisualizeUbigraph()) {
Auditor.reset(CreateUbiViz());
ExplodedNode::SetAuditor(Auditor.get());
}
// Execute the worklist algorithm.
Eng.ExecuteWorkList(Mgr->getAnalysisDeclContextManager().getStackFrame(D, 0),
Mgr->getMaxNodes());
// Release the auditor (if any) so that it doesn't monitor the graph
// created BugReporter.
ExplodedNode::SetAuditor(0);
// Visualize the exploded graph.
if (Mgr->shouldVisualizeGraphviz())
Eng.ViewGraph(Mgr->shouldTrimGraph());
// Display warnings.
Eng.getBugReporter().FlushReports();
}
void AnalysisConsumer::RunPathSensitiveChecks(Decl *D,
SetOfConstDecls *Visited) {
switch (Mgr->getLangOpts().getGC()) {
case LangOptions::NonGC:
ActionExprEngine(D, false, Visited);
break;
case LangOptions::GCOnly:
ActionExprEngine(D, true, Visited);
break;
case LangOptions::HybridGC:
ActionExprEngine(D, false, Visited);
ActionExprEngine(D, true, Visited);
break;
}
}
//===----------------------------------------------------------------------===//
// AnalysisConsumer creation.
//===----------------------------------------------------------------------===//
ASTConsumer* ento::CreateAnalysisConsumer(const Preprocessor& pp,
const std::string& outDir,
const AnalyzerOptions& opts,
ArrayRef<std::string> plugins) {
// Disable the effects of '-Werror' when using the AnalysisConsumer.
pp.getDiagnostics().setWarningsAsErrors(false);
return new AnalysisConsumer(pp, outDir, opts, plugins);
}
//===----------------------------------------------------------------------===//
// Ubigraph Visualization. FIXME: Move to separate file.
//===----------------------------------------------------------------------===//
namespace {
class UbigraphViz : public ExplodedNode::Auditor {
OwningPtr<raw_ostream> Out;
llvm::sys::Path Dir, Filename;
unsigned Cntr;
typedef llvm::DenseMap<void*,unsigned> VMap;
VMap M;
public:
UbigraphViz(raw_ostream *out, llvm::sys::Path& dir,
llvm::sys::Path& filename);
~UbigraphViz();
virtual void AddEdge(ExplodedNode *Src, ExplodedNode *Dst);
};
} // end anonymous namespace
static ExplodedNode::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::errs() << "Writing '" << Filename.str() << "'.\n";
OwningPtr<llvm::raw_fd_ostream> Stream;
Stream.reset(new llvm::raw_fd_ostream(Filename.c_str(), ErrMsg));
if (!ErrMsg.empty())
return 0;
return new UbigraphViz(Stream.take(), Dir, Filename);
}
void UbigraphViz::AddEdge(ExplodedNode *Src, ExplodedNode *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(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::errs() << "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::errs() << "Error viewing graph: " << ErrMsg << "\n";
}
// Delete the directory.
Dir.eraseFromDisk(true);
}