| // BugReporter.cpp - Generate PathDiagnostics for Bugs ------------*- C++ -*--// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file defines BugReporter, a utility class for generating |
| // PathDiagnostics for analyses based on GRSimpleVals. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/Analysis/PathSensitive/BugReporter.h" |
| #include "clang/Analysis/PathSensitive/GRExprEngine.h" |
| #include "clang/Basic/SourceManager.h" |
| #include "clang/Basic/SourceLocation.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/AST/CFG.h" |
| #include "clang/AST/Expr.h" |
| #include "clang/Analysis/ProgramPoint.h" |
| #include "clang/Analysis/PathDiagnostic.h" |
| #include <sstream> |
| |
| using namespace clang; |
| |
| BugReporter::~BugReporter() {} |
| BugType::~BugType() {} |
| BugReport::~BugReport() {} |
| RangedBugReport::~RangedBugReport() {} |
| |
| ExplodedGraph<ValueState>& BugReporter::getGraph() { return Eng.getGraph(); } |
| |
| static inline Stmt* GetStmt(const ProgramPoint& P) { |
| if (const PostStmt* PS = dyn_cast<PostStmt>(&P)) { |
| return PS->getStmt(); |
| } |
| else if (const BlockEdge* BE = dyn_cast<BlockEdge>(&P)) { |
| return BE->getSrc()->getTerminator(); |
| } |
| else if (const BlockEntrance* BE = dyn_cast<BlockEntrance>(&P)) { |
| return BE->getFirstStmt(); |
| } |
| |
| assert (false && "Unsupported ProgramPoint."); |
| return NULL; |
| } |
| |
| static inline Stmt* GetStmt(const CFGBlock* B) { |
| if (B->empty()) |
| return const_cast<Stmt*>(B->getTerminator()); |
| else |
| return (*B)[0]; |
| } |
| |
| static inline ExplodedNode<ValueState>* |
| GetNextNode(ExplodedNode<ValueState>* N) { |
| return N->pred_empty() ? NULL : *(N->pred_begin()); |
| } |
| |
| static Stmt* GetLastStmt(ExplodedNode<ValueState>* N) { |
| assert (isa<BlockEntrance>(N->getLocation())); |
| |
| for (N = GetNextNode(N); N; N = GetNextNode(N)) { |
| |
| ProgramPoint P = N->getLocation(); |
| |
| if (PostStmt* PS = dyn_cast<PostStmt>(&P)) |
| return PS->getStmt(); |
| } |
| |
| return NULL; |
| } |
| |
| static void ExecutionContinues(std::ostringstream& os, SourceManager& SMgr, |
| Stmt* S) { |
| |
| if (!S) |
| return; |
| |
| // Slow, but probably doesn't matter. |
| if (os.str().empty()) |
| os << ' '; |
| |
| os << "Execution continues on line " |
| << SMgr.getLogicalLineNumber(S->getLocStart()) << '.'; |
| } |
| |
| |
| static inline void ExecutionContinues(std::ostringstream& os, |
| SourceManager& SMgr, |
| ExplodedNode<ValueState>* N) { |
| |
| ExecutionContinues(os, SMgr, GetStmt(N->getLocation())); |
| } |
| |
| static inline void ExecutionContinues(std::ostringstream& os, |
| SourceManager& SMgr, |
| const CFGBlock* B) { |
| |
| ExecutionContinues(os, SMgr, GetStmt(B)); |
| } |
| |
| |
| Stmt* BugReport::getStmt(BugReporter& BR) const { |
| |
| ProgramPoint ProgP = EndNode->getLocation(); |
| Stmt *S = NULL; |
| |
| if (BlockEntrance* BE = dyn_cast<BlockEntrance>(&ProgP)) |
| if (BE->getBlock() == &BR.getCFG().getExit()) |
| S = GetLastStmt(EndNode); |
| if (!S) |
| S = GetStmt(ProgP); |
| |
| return S; |
| } |
| |
| PathDiagnosticPiece* |
| BugReport::getEndPath(BugReporter& BR, |
| ExplodedNode<ValueState>* EndPathNode) { |
| |
| Stmt* S = getStmt(BR); |
| |
| if (!S) |
| return NULL; |
| |
| FullSourceLoc L(S->getLocStart(), BR.getContext().getSourceManager()); |
| PathDiagnosticPiece* P = new PathDiagnosticPiece(L, getDescription()); |
| |
| const SourceRange *Beg, *End; |
| getRanges(BR, Beg, End); |
| |
| for (; Beg != End; ++Beg) |
| P->addRange(*Beg); |
| |
| return P; |
| } |
| |
| void BugReport::getRanges(BugReporter& BR, const SourceRange*& beg, |
| const SourceRange*& end) { |
| |
| if (Expr* E = dyn_cast_or_null<Expr>(getStmt(BR))) { |
| R = E->getSourceRange(); |
| beg = &R; |
| end = beg+1; |
| } |
| else |
| beg = end = 0; |
| } |
| |
| FullSourceLoc BugReport::getLocation(SourceManager& Mgr) { |
| |
| if (!EndNode) |
| return FullSourceLoc(); |
| |
| Stmt* S = GetStmt(EndNode->getLocation()); |
| |
| if (!S) |
| return FullSourceLoc(); |
| |
| return FullSourceLoc(S->getLocStart(), Mgr); |
| } |
| |
| PathDiagnosticPiece* BugReport::VisitNode(ExplodedNode<ValueState>* N, |
| ExplodedNode<ValueState>* PrevN, |
| ExplodedGraph<ValueState>& G, |
| BugReporter& BR) { |
| return NULL; |
| } |
| |
| static std::pair<ExplodedGraph<ValueState>*, ExplodedNode<ValueState>*> |
| MakeReportGraph(ExplodedGraph<ValueState>* G, ExplodedNode<ValueState>* N) { |
| |
| llvm::OwningPtr<ExplodedGraph<ValueState> > GTrim(G->Trim(&N, &N+1)); |
| |
| // Find the error node in the trimmed graph. |
| |
| ExplodedNode<ValueState>* NOld = N; |
| N = 0; |
| |
| for (ExplodedGraph<ValueState>::node_iterator |
| I = GTrim->nodes_begin(), E = GTrim->nodes_end(); I != E; ++I) { |
| |
| if (I->getState() == NOld->getState() && |
| I->getLocation() == NOld->getLocation()) { |
| N = &*I; |
| break; |
| } |
| } |
| |
| assert(N); |
| |
| // Create a new graph with a single path. |
| |
| G = new ExplodedGraph<ValueState>(GTrim->getCFG(), GTrim->getCodeDecl(), |
| GTrim->getContext()); |
| |
| |
| ExplodedNode<ValueState> *Last = 0, *First = 0; |
| |
| while (N) { |
| ExplodedNode<ValueState>* NewN = |
| G->getNode(N->getLocation(), N->getState()); |
| |
| if (!First) First = NewN; |
| if (Last) Last->addPredecessor(NewN); |
| |
| Last = NewN; |
| N = N->pred_empty() ? 0 : *(N->pred_begin()); |
| } |
| |
| return std::make_pair(G, First); |
| } |
| |
| void BugReporter::GeneratePathDiagnostic(PathDiagnostic& PD, |
| BugReport& R) { |
| |
| ExplodedNode<ValueState>* N = R.getEndNode(); |
| |
| if (!N) return; |
| |
| // Construct a new graph that contains only a single path from the error |
| // node to a root. |
| |
| const std::pair<ExplodedGraph<ValueState>*,ExplodedNode<ValueState>*> |
| GPair = MakeReportGraph(&getGraph(), N); |
| |
| llvm::OwningPtr<ExplodedGraph<ValueState> > ReportGraph(GPair.first); |
| assert(GPair.second->getLocation() == N->getLocation()); |
| N = GPair.second; |
| |
| // Start building the path diagnostic... |
| |
| if (PathDiagnosticPiece* Piece = R.getEndPath(*this, N)) |
| PD.push_back(Piece); |
| else |
| return; |
| |
| ExplodedNode<ValueState>* NextNode = N->pred_empty() |
| ? NULL : *(N->pred_begin()); |
| |
| SourceManager& SMgr = Ctx.getSourceManager(); |
| |
| while (NextNode) { |
| |
| ExplodedNode<ValueState>* LastNode = N; |
| N = NextNode; |
| NextNode = GetNextNode(N); |
| |
| ProgramPoint P = N->getLocation(); |
| |
| if (const BlockEdge* BE = dyn_cast<BlockEdge>(&P)) { |
| |
| CFGBlock* Src = BE->getSrc(); |
| CFGBlock* Dst = BE->getDst(); |
| |
| Stmt* T = Src->getTerminator(); |
| |
| if (!T) |
| continue; |
| |
| FullSourceLoc L(T->getLocStart(), SMgr); |
| |
| switch (T->getStmtClass()) { |
| default: |
| break; |
| |
| case Stmt::GotoStmtClass: |
| case Stmt::IndirectGotoStmtClass: { |
| |
| Stmt* S = GetStmt(LastNode->getLocation()); |
| |
| if (!S) |
| continue; |
| |
| std::ostringstream os; |
| |
| os << "Control jumps to line " |
| << SMgr.getLogicalLineNumber(S->getLocStart()) << ".\n"; |
| |
| PD.push_front(new PathDiagnosticPiece(L, os.str())); |
| break; |
| } |
| |
| case Stmt::SwitchStmtClass: { |
| |
| // Figure out what case arm we took. |
| |
| std::ostringstream os; |
| |
| if (Stmt* S = Dst->getLabel()) |
| switch (S->getStmtClass()) { |
| |
| default: |
| assert(false && "Not a valid switch label."); |
| continue; |
| |
| case Stmt::DefaultStmtClass: { |
| |
| os << "Control jumps to the 'default' case at line " |
| << SMgr.getLogicalLineNumber(S->getLocStart()) << ".\n"; |
| |
| break; |
| } |
| |
| case Stmt::CaseStmtClass: { |
| |
| os << "Control jumps to 'case "; |
| |
| CaseStmt* Case = cast<CaseStmt>(S); |
| Expr* LHS = Case->getLHS()->IgnoreParenCasts(); |
| |
| // Determine if it is an enum. |
| |
| bool GetRawInt = true; |
| |
| if (DeclRefExpr* DR = dyn_cast<DeclRefExpr>(LHS)) { |
| |
| // FIXME: Maybe this should be an assertion. Are there cases |
| // were it is not an EnumConstantDecl? |
| |
| EnumConstantDecl* D = dyn_cast<EnumConstantDecl>(DR->getDecl()); |
| |
| if (D) { |
| GetRawInt = false; |
| os << D->getName(); |
| } |
| } |
| |
| if (GetRawInt) { |
| |
| // Not an enum. |
| Expr* CondE = cast<SwitchStmt>(T)->getCond(); |
| unsigned bits = Ctx.getTypeSize(CondE->getType()); |
| llvm::APSInt V(bits, false); |
| |
| if (!LHS->isIntegerConstantExpr(V, Ctx, 0, true)) { |
| assert (false && "Case condition must be constant."); |
| continue; |
| } |
| |
| os << V.toString(); |
| } |
| |
| os << ":' at line " |
| << SMgr.getLogicalLineNumber(S->getLocStart()) << ".\n"; |
| |
| break; |
| |
| } |
| } |
| else { |
| os << "'Default' branch taken."; |
| ExecutionContinues(os, SMgr, LastNode); |
| } |
| |
| PD.push_front(new PathDiagnosticPiece(L, os.str())); |
| break; |
| } |
| |
| case Stmt::BreakStmtClass: |
| case Stmt::ContinueStmtClass: { |
| std::ostringstream os; |
| ExecutionContinues(os, SMgr, LastNode); |
| PD.push_front(new PathDiagnosticPiece(L, os.str())); |
| break; |
| } |
| |
| case Stmt::ConditionalOperatorClass: { |
| |
| std::ostringstream os; |
| os << "'?' condition evaluates to "; |
| |
| if (*(Src->succ_begin()+1) == Dst) |
| os << "false."; |
| else |
| os << "true."; |
| |
| PD.push_front(new PathDiagnosticPiece(L, os.str())); |
| |
| break; |
| } |
| |
| case Stmt::DoStmtClass: { |
| |
| if (*(Src->succ_begin()) == Dst) { |
| |
| std::ostringstream os; |
| |
| os << "Loop condition is true."; |
| ExecutionContinues(os, SMgr, Dst); |
| |
| PD.push_front(new PathDiagnosticPiece(L, os.str())); |
| } |
| else |
| PD.push_front(new PathDiagnosticPiece(L, |
| "Loop condition is false. Exiting loop.")); |
| |
| break; |
| } |
| |
| case Stmt::WhileStmtClass: |
| case Stmt::ForStmtClass: { |
| |
| if (*(Src->succ_begin()+1) == Dst) { |
| |
| std::ostringstream os; |
| |
| os << "Loop condition is false."; |
| ExecutionContinues(os, SMgr, Dst); |
| |
| PD.push_front(new PathDiagnosticPiece(L, os.str())); |
| } |
| else |
| PD.push_front(new PathDiagnosticPiece(L, |
| "Loop condition is true. Entering loop body.")); |
| |
| break; |
| } |
| |
| case Stmt::IfStmtClass: { |
| |
| if (*(Src->succ_begin()+1) == Dst) |
| PD.push_front(new PathDiagnosticPiece(L, "Taking false branch.")); |
| else |
| PD.push_front(new PathDiagnosticPiece(L, "Taking true branch.")); |
| |
| break; |
| } |
| } |
| } |
| |
| if (PathDiagnosticPiece* p = R.VisitNode(N, NextNode, *ReportGraph, *this)) |
| PD.push_front(p); |
| } |
| } |
| |
| bool BugTypeCacheLocation::isCached(BugReport& R) { |
| |
| ExplodedNode<ValueState>* N = R.getEndNode(); |
| |
| if (!N) |
| return false; |
| |
| // Cache the location of the error. Don't emit the same |
| // warning for the same error type that occurs at the same program |
| // location but along a different path. |
| |
| return isCached(N->getLocation()); |
| } |
| |
| bool BugTypeCacheLocation::isCached(ProgramPoint P) { |
| |
| void* p = P.getRawData(); |
| |
| if (CachedErrors.count(p)) |
| return true; |
| |
| CachedErrors.insert(p); |
| return false; |
| } |
| |
| void BugReporter::EmitWarning(BugReport& R) { |
| |
| if (R.getBugType().isCached(R)) |
| return; |
| |
| llvm::OwningPtr<PathDiagnostic> D(new PathDiagnostic(R.getName())); |
| GeneratePathDiagnostic(*D.get(), R); |
| |
| // Get the meta data. |
| |
| std::pair<const char**, const char**> Meta = R.getExtraDescriptiveText(); |
| |
| for (const char** s = Meta.first; s != Meta.second; ++s) |
| D->addMeta(*s); |
| |
| // Emit a full diagnostic for the path if we have a PathDiagnosticClient. |
| |
| if (PD && !D->empty()) { |
| PD->HandlePathDiagnostic(D.take()); |
| return; |
| } |
| |
| // We don't have a PathDiagnosticClient, but we can still emit a single |
| // line diagnostic. Determine the location. |
| |
| FullSourceLoc L = D->empty() ? R.getLocation(Ctx.getSourceManager()) |
| : D->back()->getLocation(); |
| |
| |
| // Determine the range. |
| |
| const SourceRange *Beg, *End; |
| |
| if (!D->empty()) { |
| Beg = D->back()->ranges_begin(); |
| End = D->back()->ranges_end(); |
| } |
| else |
| R.getRanges(*this, Beg, End); |
| |
| if (PD) { |
| PathDiagnosticPiece* piece = new PathDiagnosticPiece(L, R.getDescription()); |
| |
| for ( ; Beg != End; ++Beg) |
| piece->addRange(*Beg); |
| |
| D->push_back(piece); |
| PD->HandlePathDiagnostic(D.take()); |
| } |
| else { |
| std::ostringstream os; |
| os << "[CHECKER] "; |
| |
| if (D->empty()) |
| os << R.getDescription(); |
| else |
| os << D->back()->getString(); |
| |
| |
| unsigned ErrorDiag = Diag.getCustomDiagID(Diagnostic::Warning, |
| os.str().c_str()); |
| |
| Diag.Report(L, ErrorDiag, NULL, 0, Beg, End - Beg); |
| } |
| } |