diff options
Diffstat (limited to 'contrib/llvm/tools/clang/lib/Checker/BugReporter.cpp')
| -rw-r--r-- | contrib/llvm/tools/clang/lib/Checker/BugReporter.cpp | 1896 |
1 files changed, 1896 insertions, 0 deletions
diff --git a/contrib/llvm/tools/clang/lib/Checker/BugReporter.cpp b/contrib/llvm/tools/clang/lib/Checker/BugReporter.cpp new file mode 100644 index 0000000..3bcc03f --- /dev/null +++ b/contrib/llvm/tools/clang/lib/Checker/BugReporter.cpp @@ -0,0 +1,1896 @@ +// 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. +// +//===----------------------------------------------------------------------===// + +#include "clang/Checker/BugReporter/BugReporter.h" +#include "clang/Checker/BugReporter/BugType.h" +#include "clang/Checker/PathSensitive/GRExprEngine.h" +#include "clang/AST/ASTContext.h" +#include "clang/Analysis/CFG.h" +#include "clang/AST/Expr.h" +#include "clang/AST/ParentMap.h" +#include "clang/AST/StmtObjC.h" +#include "clang/Basic/SourceManager.h" +#include "clang/Analysis/ProgramPoint.h" +#include "clang/Checker/BugReporter/PathDiagnostic.h" +#include "llvm/Support/raw_ostream.h" +#include "llvm/ADT/DenseMap.h" +#include "llvm/ADT/STLExtras.h" +#include "llvm/ADT/OwningPtr.h" +#include <queue> + +using namespace clang; + +BugReporterVisitor::~BugReporterVisitor() {} +BugReporterContext::~BugReporterContext() { + for (visitor_iterator I = visitor_begin(), E = visitor_end(); I != E; ++I) + if ((*I)->isOwnedByReporterContext()) delete *I; +} + +void BugReporterContext::addVisitor(BugReporterVisitor* visitor) { + if (!visitor) + return; + + llvm::FoldingSetNodeID ID; + visitor->Profile(ID); + void *InsertPos; + + if (CallbacksSet.FindNodeOrInsertPos(ID, InsertPos)) { + delete visitor; + return; + } + + CallbacksSet.InsertNode(visitor, InsertPos); + Callbacks = F.Add(visitor, Callbacks); +} + +//===----------------------------------------------------------------------===// +// Helper routines for walking the ExplodedGraph and fetching statements. +//===----------------------------------------------------------------------===// + +static inline const Stmt* GetStmt(const ProgramPoint &P) { + if (const StmtPoint* SP = dyn_cast<StmtPoint>(&P)) + return SP->getStmt(); + else if (const BlockEdge* BE = dyn_cast<BlockEdge>(&P)) + return BE->getSrc()->getTerminator(); + + return 0; +} + +static inline const ExplodedNode* +GetPredecessorNode(const ExplodedNode* N) { + return N->pred_empty() ? NULL : *(N->pred_begin()); +} + +static inline const ExplodedNode* +GetSuccessorNode(const ExplodedNode* N) { + return N->succ_empty() ? NULL : *(N->succ_begin()); +} + +static const Stmt* GetPreviousStmt(const ExplodedNode* N) { + for (N = GetPredecessorNode(N); N; N = GetPredecessorNode(N)) + if (const Stmt *S = GetStmt(N->getLocation())) + return S; + + return 0; +} + +static const Stmt* GetNextStmt(const ExplodedNode* N) { + for (N = GetSuccessorNode(N); N; N = GetSuccessorNode(N)) + if (const Stmt *S = GetStmt(N->getLocation())) { + // Check if the statement is '?' or '&&'/'||'. These are "merges", + // not actual statement points. + switch (S->getStmtClass()) { + case Stmt::ChooseExprClass: + case Stmt::ConditionalOperatorClass: continue; + case Stmt::BinaryOperatorClass: { + BinaryOperator::Opcode Op = cast<BinaryOperator>(S)->getOpcode(); + if (Op == BinaryOperator::LAnd || Op == BinaryOperator::LOr) + continue; + break; + } + default: + break; + } + + // Some expressions don't have locations. + if (S->getLocStart().isInvalid()) + continue; + + return S; + } + + return 0; +} + +static inline const Stmt* +GetCurrentOrPreviousStmt(const ExplodedNode* N) { + if (const Stmt *S = GetStmt(N->getLocation())) + return S; + + return GetPreviousStmt(N); +} + +static inline const Stmt* +GetCurrentOrNextStmt(const ExplodedNode* N) { + if (const Stmt *S = GetStmt(N->getLocation())) + return S; + + return GetNextStmt(N); +} + +//===----------------------------------------------------------------------===// +// PathDiagnosticBuilder and its associated routines and helper objects. +//===----------------------------------------------------------------------===// + +typedef llvm::DenseMap<const ExplodedNode*, +const ExplodedNode*> NodeBackMap; + +namespace { +class NodeMapClosure : public BugReport::NodeResolver { + NodeBackMap& M; +public: + NodeMapClosure(NodeBackMap *m) : M(*m) {} + ~NodeMapClosure() {} + + const ExplodedNode* getOriginalNode(const ExplodedNode* N) { + NodeBackMap::iterator I = M.find(N); + return I == M.end() ? 0 : I->second; + } +}; + +class PathDiagnosticBuilder : public BugReporterContext { + BugReport *R; + PathDiagnosticClient *PDC; + llvm::OwningPtr<ParentMap> PM; + NodeMapClosure NMC; +public: + PathDiagnosticBuilder(GRBugReporter &br, + BugReport *r, NodeBackMap *Backmap, + PathDiagnosticClient *pdc) + : BugReporterContext(br), + R(r), PDC(pdc), NMC(Backmap) { + addVisitor(R); + } + + PathDiagnosticLocation ExecutionContinues(const ExplodedNode* N); + + PathDiagnosticLocation ExecutionContinues(llvm::raw_string_ostream& os, + const ExplodedNode* N); + + Decl const &getCodeDecl() { return R->getEndNode()->getCodeDecl(); } + + ParentMap& getParentMap() { return R->getEndNode()->getParentMap(); } + + const Stmt *getParent(const Stmt *S) { + return getParentMap().getParent(S); + } + + virtual NodeMapClosure& getNodeResolver() { return NMC; } + BugReport& getReport() { return *R; } + + PathDiagnosticLocation getEnclosingStmtLocation(const Stmt *S); + + PathDiagnosticLocation + getEnclosingStmtLocation(const PathDiagnosticLocation &L) { + if (const Stmt *S = L.asStmt()) + return getEnclosingStmtLocation(S); + + return L; + } + + PathDiagnosticClient::PathGenerationScheme getGenerationScheme() const { + return PDC ? PDC->getGenerationScheme() : PathDiagnosticClient::Extensive; + } + + bool supportsLogicalOpControlFlow() const { + return PDC ? PDC->supportsLogicalOpControlFlow() : true; + } +}; +} // end anonymous namespace + +PathDiagnosticLocation +PathDiagnosticBuilder::ExecutionContinues(const ExplodedNode* N) { + if (const Stmt *S = GetNextStmt(N)) + return PathDiagnosticLocation(S, getSourceManager()); + + return FullSourceLoc(N->getLocationContext()->getDecl()->getBodyRBrace(), + getSourceManager()); +} + +PathDiagnosticLocation +PathDiagnosticBuilder::ExecutionContinues(llvm::raw_string_ostream& os, + const ExplodedNode* N) { + + // Slow, but probably doesn't matter. + if (os.str().empty()) + os << ' '; + + const PathDiagnosticLocation &Loc = ExecutionContinues(N); + + if (Loc.asStmt()) + os << "Execution continues on line " + << getSourceManager().getInstantiationLineNumber(Loc.asLocation()) + << '.'; + else { + os << "Execution jumps to the end of the "; + const Decl *D = N->getLocationContext()->getDecl(); + if (isa<ObjCMethodDecl>(D)) + os << "method"; + else if (isa<FunctionDecl>(D)) + os << "function"; + else { + assert(isa<BlockDecl>(D)); + os << "anonymous block"; + } + os << '.'; + } + + return Loc; +} + +static bool IsNested(const Stmt *S, ParentMap &PM) { + if (isa<Expr>(S) && PM.isConsumedExpr(cast<Expr>(S))) + return true; + + const Stmt *Parent = PM.getParentIgnoreParens(S); + + if (Parent) + switch (Parent->getStmtClass()) { + case Stmt::ForStmtClass: + case Stmt::DoStmtClass: + case Stmt::WhileStmtClass: + return true; + default: + break; + } + + return false; +} + +PathDiagnosticLocation +PathDiagnosticBuilder::getEnclosingStmtLocation(const Stmt *S) { + assert(S && "Null Stmt* passed to getEnclosingStmtLocation"); + ParentMap &P = getParentMap(); + SourceManager &SMgr = getSourceManager(); + + while (IsNested(S, P)) { + const Stmt *Parent = P.getParentIgnoreParens(S); + + if (!Parent) + break; + + switch (Parent->getStmtClass()) { + case Stmt::BinaryOperatorClass: { + const BinaryOperator *B = cast<BinaryOperator>(Parent); + if (B->isLogicalOp()) + return PathDiagnosticLocation(S, SMgr); + break; + } + case Stmt::CompoundStmtClass: + case Stmt::StmtExprClass: + return PathDiagnosticLocation(S, SMgr); + case Stmt::ChooseExprClass: + // Similar to '?' if we are referring to condition, just have the edge + // point to the entire choose expression. + if (cast<ChooseExpr>(Parent)->getCond() == S) + return PathDiagnosticLocation(Parent, SMgr); + else + return PathDiagnosticLocation(S, SMgr); + case Stmt::ConditionalOperatorClass: + // For '?', if we are referring to condition, just have the edge point + // to the entire '?' expression. + if (cast<ConditionalOperator>(Parent)->getCond() == S) + return PathDiagnosticLocation(Parent, SMgr); + else + return PathDiagnosticLocation(S, SMgr); + case Stmt::DoStmtClass: + return PathDiagnosticLocation(S, SMgr); + case Stmt::ForStmtClass: + if (cast<ForStmt>(Parent)->getBody() == S) + return PathDiagnosticLocation(S, SMgr); + break; + case Stmt::IfStmtClass: + if (cast<IfStmt>(Parent)->getCond() != S) + return PathDiagnosticLocation(S, SMgr); + break; + case Stmt::ObjCForCollectionStmtClass: + if (cast<ObjCForCollectionStmt>(Parent)->getBody() == S) + return PathDiagnosticLocation(S, SMgr); + break; + case Stmt::WhileStmtClass: + if (cast<WhileStmt>(Parent)->getCond() != S) + return PathDiagnosticLocation(S, SMgr); + break; + default: + break; + } + + S = Parent; + } + + assert(S && "Cannot have null Stmt for PathDiagnosticLocation"); + + // Special case: DeclStmts can appear in for statement declarations, in which + // case the ForStmt is the context. + if (isa<DeclStmt>(S)) { + if (const Stmt *Parent = P.getParent(S)) { + switch (Parent->getStmtClass()) { + case Stmt::ForStmtClass: + case Stmt::ObjCForCollectionStmtClass: + return PathDiagnosticLocation(Parent, SMgr); + default: + break; + } + } + } + else if (isa<BinaryOperator>(S)) { + // Special case: the binary operator represents the initialization + // code in a for statement (this can happen when the variable being + // initialized is an old variable. + if (const ForStmt *FS = + dyn_cast_or_null<ForStmt>(P.getParentIgnoreParens(S))) { + if (FS->getInit() == S) + return PathDiagnosticLocation(FS, SMgr); + } + } + + return PathDiagnosticLocation(S, SMgr); +} + +//===----------------------------------------------------------------------===// +// ScanNotableSymbols: closure-like callback for scanning Store bindings. +//===----------------------------------------------------------------------===// + +static const VarDecl* +GetMostRecentVarDeclBinding(const ExplodedNode* N, + GRStateManager& VMgr, SVal X) { + + for ( ; N ; N = N->pred_empty() ? 0 : *N->pred_begin()) { + + ProgramPoint P = N->getLocation(); + + if (!isa<PostStmt>(P)) + continue; + + const DeclRefExpr* DR = dyn_cast<DeclRefExpr>(cast<PostStmt>(P).getStmt()); + + if (!DR) + continue; + + SVal Y = N->getState()->getSVal(DR); + + if (X != Y) + continue; + + const VarDecl* VD = dyn_cast<VarDecl>(DR->getDecl()); + + if (!VD) + continue; + + return VD; + } + + return 0; +} + +namespace { +class NotableSymbolHandler +: public StoreManager::BindingsHandler { + + SymbolRef Sym; + const GRState* PrevSt; + const Stmt* S; + GRStateManager& VMgr; + const ExplodedNode* Pred; + PathDiagnostic& PD; + BugReporter& BR; + +public: + + NotableSymbolHandler(SymbolRef sym, const GRState* prevst, const Stmt* s, + GRStateManager& vmgr, const ExplodedNode* pred, + PathDiagnostic& pd, BugReporter& br) + : Sym(sym), PrevSt(prevst), S(s), VMgr(vmgr), Pred(pred), PD(pd), BR(br) {} + + bool HandleBinding(StoreManager& SMgr, Store store, const MemRegion* R, + SVal V) { + + SymbolRef ScanSym = V.getAsSymbol(); + + if (ScanSym != Sym) + return true; + + // Check if the previous state has this binding. + SVal X = PrevSt->getSVal(loc::MemRegionVal(R)); + + if (X == V) // Same binding? + return true; + + // Different binding. Only handle assignments for now. We don't pull + // this check out of the loop because we will eventually handle other + // cases. + + VarDecl *VD = 0; + + if (const BinaryOperator* B = dyn_cast<BinaryOperator>(S)) { + if (!B->isAssignmentOp()) + return true; + + // What variable did we assign to? + DeclRefExpr* DR = dyn_cast<DeclRefExpr>(B->getLHS()->IgnoreParenCasts()); + + if (!DR) + return true; + + VD = dyn_cast<VarDecl>(DR->getDecl()); + } + else if (const DeclStmt* DS = dyn_cast<DeclStmt>(S)) { + // FIXME: Eventually CFGs won't have DeclStmts. Right now we + // assume that each DeclStmt has a single Decl. This invariant + // holds by contruction in the CFG. + VD = dyn_cast<VarDecl>(*DS->decl_begin()); + } + + if (!VD) + return true; + + // What is the most recently referenced variable with this binding? + const VarDecl* MostRecent = GetMostRecentVarDeclBinding(Pred, VMgr, V); + + if (!MostRecent) + return true; + + // Create the diagnostic. + FullSourceLoc L(S->getLocStart(), BR.getSourceManager()); + + if (Loc::IsLocType(VD->getType())) { + std::string msg = "'" + std::string(VD->getNameAsString()) + + "' now aliases '" + MostRecent->getNameAsString() + "'"; + + PD.push_front(new PathDiagnosticEventPiece(L, msg)); + } + + return true; + } +}; +} + +static void HandleNotableSymbol(const ExplodedNode* N, + const Stmt* S, + SymbolRef Sym, BugReporter& BR, + PathDiagnostic& PD) { + + const ExplodedNode* Pred = N->pred_empty() ? 0 : *N->pred_begin(); + const GRState* PrevSt = Pred ? Pred->getState() : 0; + + if (!PrevSt) + return; + + // Look at the region bindings of the current state that map to the + // specified symbol. Are any of them not in the previous state? + GRStateManager& VMgr = cast<GRBugReporter>(BR).getStateManager(); + NotableSymbolHandler H(Sym, PrevSt, S, VMgr, Pred, PD, BR); + cast<GRBugReporter>(BR).getStateManager().iterBindings(N->getState(), H); +} + +namespace { +class ScanNotableSymbols +: public StoreManager::BindingsHandler { + + llvm::SmallSet<SymbolRef, 10> AlreadyProcessed; + const ExplodedNode* N; + const Stmt* S; + GRBugReporter& BR; + PathDiagnostic& PD; + +public: + ScanNotableSymbols(const ExplodedNode* n, const Stmt* s, + GRBugReporter& br, PathDiagnostic& pd) + : N(n), S(s), BR(br), PD(pd) {} + + bool HandleBinding(StoreManager& SMgr, Store store, + const MemRegion* R, SVal V) { + + SymbolRef ScanSym = V.getAsSymbol(); + + if (!ScanSym) + return true; + + if (!BR.isNotable(ScanSym)) + return true; + + if (AlreadyProcessed.count(ScanSym)) + return true; + + AlreadyProcessed.insert(ScanSym); + + HandleNotableSymbol(N, S, ScanSym, BR, PD); + return true; + } +}; +} // end anonymous namespace + +//===----------------------------------------------------------------------===// +// "Minimal" path diagnostic generation algorithm. +//===----------------------------------------------------------------------===// + +static void CompactPathDiagnostic(PathDiagnostic &PD, const SourceManager& SM); + +static void GenerateMinimalPathDiagnostic(PathDiagnostic& PD, + PathDiagnosticBuilder &PDB, + const ExplodedNode *N) { + + SourceManager& SMgr = PDB.getSourceManager(); + const ExplodedNode* NextNode = N->pred_empty() + ? NULL : *(N->pred_begin()); + while (NextNode) { + N = NextNode; + NextNode = GetPredecessorNode(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 Start(T->getLocStart(), SMgr); + + switch (T->getStmtClass()) { + default: + break; + + case Stmt::GotoStmtClass: + case Stmt::IndirectGotoStmtClass: { + const Stmt* S = GetNextStmt(N); + + if (!S) + continue; + + std::string sbuf; + llvm::raw_string_ostream os(sbuf); + const PathDiagnosticLocation &End = PDB.getEnclosingStmtLocation(S); + + os << "Control jumps to line " + << End.asLocation().getInstantiationLineNumber(); + PD.push_front(new PathDiagnosticControlFlowPiece(Start, End, + os.str())); + break; + } + + case Stmt::SwitchStmtClass: { + // Figure out what case arm we took. + std::string sbuf; + llvm::raw_string_ostream os(sbuf); + + if (Stmt* S = Dst->getLabel()) { + PathDiagnosticLocation End(S, SMgr); + + switch (S->getStmtClass()) { + default: + os << "No cases match in the switch statement. " + "Control jumps to line " + << End.asLocation().getInstantiationLineNumber(); + break; + case Stmt::DefaultStmtClass: + os << "Control jumps to the 'default' case at line " + << End.asLocation().getInstantiationLineNumber(); + 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; + } + } + + if (GetRawInt) + os << LHS->EvaluateAsInt(PDB.getASTContext()); + + os << ":' at line " + << End.asLocation().getInstantiationLineNumber(); + break; + } + } + PD.push_front(new PathDiagnosticControlFlowPiece(Start, End, + os.str())); + } + else { + os << "'Default' branch taken. "; + const PathDiagnosticLocation &End = PDB.ExecutionContinues(os, N); + PD.push_front(new PathDiagnosticControlFlowPiece(Start, End, + os.str())); + } + + break; + } + + case Stmt::BreakStmtClass: + case Stmt::ContinueStmtClass: { + std::string sbuf; + llvm::raw_string_ostream os(sbuf); + PathDiagnosticLocation End = PDB.ExecutionContinues(os, N); + PD.push_front(new PathDiagnosticControlFlowPiece(Start, End, + os.str())); + break; + } + + // Determine control-flow for ternary '?'. + case Stmt::ConditionalOperatorClass: { + std::string sbuf; + llvm::raw_string_ostream os(sbuf); + os << "'?' condition is "; + + if (*(Src->succ_begin()+1) == Dst) + os << "false"; + else + os << "true"; + + PathDiagnosticLocation End = PDB.ExecutionContinues(N); + + if (const Stmt *S = End.asStmt()) + End = PDB.getEnclosingStmtLocation(S); + + PD.push_front(new PathDiagnosticControlFlowPiece(Start, End, + os.str())); + break; + } + + // Determine control-flow for short-circuited '&&' and '||'. + case Stmt::BinaryOperatorClass: { + if (!PDB.supportsLogicalOpControlFlow()) + break; + + BinaryOperator *B = cast<BinaryOperator>(T); + std::string sbuf; + llvm::raw_string_ostream os(sbuf); + os << "Left side of '"; + + if (B->getOpcode() == BinaryOperator::LAnd) { + os << "&&" << "' is "; + + if (*(Src->succ_begin()+1) == Dst) { + os << "false"; + PathDiagnosticLocation End(B->getLHS(), SMgr); + PathDiagnosticLocation Start(B->getOperatorLoc(), SMgr); + PD.push_front(new PathDiagnosticControlFlowPiece(Start, End, + os.str())); + } + else { + os << "true"; + PathDiagnosticLocation Start(B->getLHS(), SMgr); + PathDiagnosticLocation End = PDB.ExecutionContinues(N); + PD.push_front(new PathDiagnosticControlFlowPiece(Start, End, + os.str())); + } + } + else { + assert(B->getOpcode() == BinaryOperator::LOr); + os << "||" << "' is "; + + if (*(Src->succ_begin()+1) == Dst) { + os << "false"; + PathDiagnosticLocation Start(B->getLHS(), SMgr); + PathDiagnosticLocation End = PDB.ExecutionContinues(N); + PD.push_front(new PathDiagnosticControlFlowPiece(Start, End, + os.str())); + } + else { + os << "true"; + PathDiagnosticLocation End(B->getLHS(), SMgr); + PathDiagnosticLocation Start(B->getOperatorLoc(), SMgr); + PD.push_front(new PathDiagnosticControlFlowPiece(Start, End, + os.str())); + } + } + + break; + } + + case Stmt::DoStmtClass: { + if (*(Src->succ_begin()) == Dst) { + std::string sbuf; + llvm::raw_string_ostream os(sbuf); + + os << "Loop condition is true. "; + PathDiagnosticLocation End = PDB.ExecutionContinues(os, N); + + if (const Stmt *S = End.asStmt()) + End = PDB.getEnclosingStmtLocation(S); + + PD.push_front(new PathDiagnosticControlFlowPiece(Start, End, + os.str())); + } + else { + PathDiagnosticLocation End = PDB.ExecutionContinues(N); + + if (const Stmt *S = End.asStmt()) + End = PDB.getEnclosingStmtLocation(S); + + PD.push_front(new PathDiagnosticControlFlowPiece(Start, End, + "Loop condition is false. Exiting loop")); + } + + break; + } + + case Stmt::WhileStmtClass: + case Stmt::ForStmtClass: { + if (*(Src->succ_begin()+1) == Dst) { + std::string sbuf; + llvm::raw_string_ostream os(sbuf); + + os << "Loop condition is false. "; + PathDiagnosticLocation End = PDB.ExecutionContinues(os, N); + if (const Stmt *S = End.asStmt()) + End = PDB.getEnclosingStmtLocation(S); + + PD.push_front(new PathDiagnosticControlFlowPiece(Start, End, + os.str())); + } + else { + PathDiagnosticLocation End = PDB.ExecutionContinues(N); + if (const Stmt *S = End.asStmt()) + End = PDB.getEnclosingStmtLocation(S); + + PD.push_front(new PathDiagnosticControlFlowPiece(Start, End, + "Loop condition is true. Entering loop body")); + } + + break; + } + + case Stmt::IfStmtClass: { + PathDiagnosticLocation End = PDB.ExecutionContinues(N); + + if (const Stmt *S = End.asStmt()) + End = PDB.getEnclosingStmtLocation(S); + + if (*(Src->succ_begin()+1) == Dst) + PD.push_front(new PathDiagnosticControlFlowPiece(Start, End, + "Taking false branch")); + else + PD.push_front(new PathDiagnosticControlFlowPiece(Start, End, + "Taking true branch")); + + break; + } + } + } + + if (NextNode) { + for (BugReporterContext::visitor_iterator I = PDB.visitor_begin(), + E = PDB.visitor_end(); I!=E; ++I) { + if (PathDiagnosticPiece* p = (*I)->VisitNode(N, NextNode, PDB)) + PD.push_front(p); + } + } + + if (const PostStmt* PS = dyn_cast<PostStmt>(&P)) { + // Scan the region bindings, and see if a "notable" symbol has a new + // lval binding. + ScanNotableSymbols SNS(N, PS->getStmt(), PDB.getBugReporter(), PD); + PDB.getStateManager().iterBindings(N->getState(), SNS); + } + } + + // After constructing the full PathDiagnostic, do a pass over it to compact + // PathDiagnosticPieces that occur within a macro. + CompactPathDiagnostic(PD, PDB.getSourceManager()); +} + +//===----------------------------------------------------------------------===// +// "Extensive" PathDiagnostic generation. +//===----------------------------------------------------------------------===// + +static bool IsControlFlowExpr(const Stmt *S) { + const Expr *E = dyn_cast<Expr>(S); + + if (!E) + return false; + + E = E->IgnoreParenCasts(); + + if (isa<ConditionalOperator>(E)) + return true; + + if (const BinaryOperator *B = dyn_cast<BinaryOperator>(E)) + if (B->isLogicalOp()) + return true; + + return false; +} + +namespace { +class ContextLocation : public PathDiagnosticLocation { + bool IsDead; +public: + ContextLocation(const PathDiagnosticLocation &L, bool isdead = false) + : PathDiagnosticLocation(L), IsDead(isdead) {} + + void markDead() { IsDead = true; } + bool isDead() const { return IsDead; } +}; + +class EdgeBuilder { + std::vector<ContextLocation> CLocs; + typedef std::vector<ContextLocation>::iterator iterator; + PathDiagnostic &PD; + PathDiagnosticBuilder &PDB; + PathDiagnosticLocation PrevLoc; + + bool IsConsumedExpr(const PathDiagnosticLocation &L); + + bool containsLocation(const PathDiagnosticLocation &Container, + const PathDiagnosticLocation &Containee); + + PathDiagnosticLocation getContextLocation(const PathDiagnosticLocation &L); + + PathDiagnosticLocation cleanUpLocation(PathDiagnosticLocation L, + bool firstCharOnly = false) { + if (const Stmt *S = L.asStmt()) { + const Stmt *Original = S; + while (1) { + // Adjust the location for some expressions that are best referenced + // by one of their subexpressions. + switch (S->getStmtClass()) { + default: + break; + case Stmt::ParenExprClass: + S = cast<ParenExpr>(S)->IgnoreParens(); + firstCharOnly = true; + continue; + case Stmt::ConditionalOperatorClass: + S = cast<ConditionalOperator>(S)->getCond(); + firstCharOnly = true; + continue; + case Stmt::ChooseExprClass: + S = cast<ChooseExpr>(S)->getCond(); + firstCharOnly = true; + continue; + case Stmt::BinaryOperatorClass: + S = cast<BinaryOperator>(S)->getLHS(); + firstCharOnly = true; + continue; + } + + break; + } + + if (S != Original) + L = PathDiagnosticLocation(S, L.getManager()); + } + + if (firstCharOnly) + L = PathDiagnosticLocation(L.asLocation()); + + return L; + } + + void popLocation() { + if (!CLocs.back().isDead() && CLocs.back().asLocation().isFileID()) { + // For contexts, we only one the first character as the range. + rawAddEdge(cleanUpLocation(CLocs.back(), true)); + } + CLocs.pop_back(); + } + + PathDiagnosticLocation IgnoreParens(const PathDiagnosticLocation &L); + +public: + EdgeBuilder(PathDiagnostic &pd, PathDiagnosticBuilder &pdb) + : PD(pd), PDB(pdb) { + + // If the PathDiagnostic already has pieces, add the enclosing statement + // of the first piece as a context as well. + if (!PD.empty()) { + PrevLoc = PD.begin()->getLocation(); + + if (const Stmt *S = PrevLoc.asStmt()) + addExtendedContext(PDB.getEnclosingStmtLocation(S).asStmt()); + } + } + + ~EdgeBuilder() { + while (!CLocs.empty()) popLocation(); + + // Finally, add an initial edge from the start location of the first + // statement (if it doesn't already exist). + // FIXME: Should handle CXXTryStmt if analyser starts supporting C++. + if (const CompoundStmt *CS = + PDB.getCodeDecl().getCompoundBody()) + if (!CS->body_empty()) { + SourceLocation Loc = (*CS->body_begin())->getLocStart(); + rawAddEdge(PathDiagnosticLocation(Loc, PDB.getSourceManager())); + } + + } + + void addEdge(PathDiagnosticLocation NewLoc, bool alwaysAdd = false); + + void addEdge(const Stmt *S, bool alwaysAdd = false) { + addEdge(PathDiagnosticLocation(S, PDB.getSourceManager()), alwaysAdd); + } + + void rawAddEdge(PathDiagnosticLocation NewLoc); + + void addContext(const Stmt *S); + void addExtendedContext(const Stmt *S); +}; +} // end anonymous namespace + + +PathDiagnosticLocation +EdgeBuilder::getContextLocation(const PathDiagnosticLocation &L) { + if (const Stmt *S = L.asStmt()) { + if (IsControlFlowExpr(S)) + return L; + + return PDB.getEnclosingStmtLocation(S); + } + + return L; +} + +bool EdgeBuilder::containsLocation(const PathDiagnosticLocation &Container, + const PathDiagnosticLocation &Containee) { + + if (Container == Containee) + return true; + + if (Container.asDecl()) + return true; + + if (const Stmt *S = Containee.asStmt()) + if (const Stmt *ContainerS = Container.asStmt()) { + while (S) { + if (S == ContainerS) + return true; + S = PDB.getParent(S); + } + return false; + } + + // Less accurate: compare using source ranges. + SourceRange ContainerR = Container.asRange(); + SourceRange ContaineeR = Containee.asRange(); + + SourceManager &SM = PDB.getSourceManager(); + SourceLocation ContainerRBeg = SM.getInstantiationLoc(ContainerR.getBegin()); + SourceLocation ContainerREnd = SM.getInstantiationLoc(ContainerR.getEnd()); + SourceLocation ContaineeRBeg = SM.getInstantiationLoc(ContaineeR.getBegin()); + SourceLocation ContaineeREnd = SM.getInstantiationLoc(ContaineeR.getEnd()); + + unsigned ContainerBegLine = SM.getInstantiationLineNumber(ContainerRBeg); + unsigned ContainerEndLine = SM.getInstantiationLineNumber(ContainerREnd); + unsigned ContaineeBegLine = SM.getInstantiationLineNumber(ContaineeRBeg); + unsigned ContaineeEndLine = SM.getInstantiationLineNumber(ContaineeREnd); + + assert(ContainerBegLine <= ContainerEndLine); + assert(ContaineeBegLine <= ContaineeEndLine); + + return (ContainerBegLine <= ContaineeBegLine && + ContainerEndLine >= ContaineeEndLine && + (ContainerBegLine != ContaineeBegLine || + SM.getInstantiationColumnNumber(ContainerRBeg) <= + SM.getInstantiationColumnNumber(ContaineeRBeg)) && + (ContainerEndLine != ContaineeEndLine || + SM.getInstantiationColumnNumber(ContainerREnd) >= + SM.getInstantiationColumnNumber(ContainerREnd))); +} + +PathDiagnosticLocation +EdgeBuilder::IgnoreParens(const PathDiagnosticLocation &L) { + if (const Expr* E = dyn_cast_or_null<Expr>(L.asStmt())) + return PathDiagnosticLocation(E->IgnoreParenCasts(), + PDB.getSourceManager()); + return L; +} + +void EdgeBuilder::rawAddEdge(PathDiagnosticLocation NewLoc) { + if (!PrevLoc.isValid()) { + PrevLoc = NewLoc; + return; + } + + const PathDiagnosticLocation &NewLocClean = cleanUpLocation(NewLoc); + const PathDiagnosticLocation &PrevLocClean = cleanUpLocation(PrevLoc); + + if (NewLocClean.asLocation() == PrevLocClean.asLocation()) + return; + + // FIXME: Ignore intra-macro edges for now. + if (NewLocClean.asLocation().getInstantiationLoc() == + PrevLocClean.asLocation().getInstantiationLoc()) + return; + + PD.push_front(new PathDiagnosticControlFlowPiece(NewLocClean, PrevLocClean)); + PrevLoc = NewLoc; +} + +void EdgeBuilder::addEdge(PathDiagnosticLocation NewLoc, bool alwaysAdd) { + + if (!alwaysAdd && NewLoc.asLocation().isMacroID()) + return; + + const PathDiagnosticLocation &CLoc = getContextLocation(NewLoc); + + while (!CLocs.empty()) { + ContextLocation &TopContextLoc = CLocs.back(); + + // Is the top location context the same as the one for the new location? + if (TopContextLoc == CLoc) { + if (alwaysAdd) { + if (IsConsumedExpr(TopContextLoc) && + !IsControlFlowExpr(TopContextLoc.asStmt())) + TopContextLoc.markDead(); + + rawAddEdge(NewLoc); + } + + return; + } + + if (containsLocation(TopContextLoc, CLoc)) { + if (alwaysAdd) { + rawAddEdge(NewLoc); + + if (IsConsumedExpr(CLoc) && !IsControlFlowExpr(CLoc.asStmt())) { + CLocs.push_back(ContextLocation(CLoc, true)); + return; + } + } + + CLocs.push_back(CLoc); + return; + } + + // Context does not contain the location. Flush it. + popLocation(); + } + + // If we reach here, there is no enclosing context. Just add the edge. + rawAddEdge(NewLoc); +} + +bool EdgeBuilder::IsConsumedExpr(const PathDiagnosticLocation &L) { + if (const Expr *X = dyn_cast_or_null<Expr>(L.asStmt())) + return PDB.getParentMap().isConsumedExpr(X) && !IsControlFlowExpr(X); + + return false; +} + +void EdgeBuilder::addExtendedContext(const Stmt *S) { + if (!S) + return; + + const Stmt *Parent = PDB.getParent(S); + while (Parent) { + if (isa<CompoundStmt>(Parent)) + Parent = PDB.getParent(Parent); + else + break; + } + + if (Parent) { + switch (Parent->getStmtClass()) { + case Stmt::DoStmtClass: + case Stmt::ObjCAtSynchronizedStmtClass: + addContext(Parent); + default: + break; + } + } + + addContext(S); +} + +void EdgeBuilder::addContext(const Stmt *S) { + if (!S) + return; + + PathDiagnosticLocation L(S, PDB.getSourceManager()); + + while (!CLocs.empty()) { + const PathDiagnosticLocation &TopContextLoc = CLocs.back(); + + // Is the top location context the same as the one for the new location? + if (TopContextLoc == L) + return; + + if (containsLocation(TopContextLoc, L)) { + CLocs.push_back(L); + return; + } + + // Context does not contain the location. Flush it. + popLocation(); + } + + CLocs.push_back(L); +} + +static void GenerateExtensivePathDiagnostic(PathDiagnostic& PD, + PathDiagnosticBuilder &PDB, + const ExplodedNode *N) { + EdgeBuilder EB(PD, PDB); + + const ExplodedNode* NextNode = N->pred_empty() ? NULL : *(N->pred_begin()); + while (NextNode) { + N = NextNode; + NextNode = GetPredecessorNode(N); + ProgramPoint P = N->getLocation(); + + do { + // Block edges. + if (const BlockEdge *BE = dyn_cast<BlockEdge>(&P)) { + const CFGBlock &Blk = *BE->getSrc(); + const Stmt *Term = Blk.getTerminator(); + + // Are we jumping to the head of a loop? Add a special diagnostic. + if (const Stmt *Loop = BE->getDst()->getLoopTarget()) { + PathDiagnosticLocation L(Loop, PDB.getSourceManager()); + const CompoundStmt *CS = NULL; + + if (!Term) { + if (const ForStmt *FS = dyn_cast<ForStmt>(Loop)) + CS = dyn_cast<CompoundStmt>(FS->getBody()); + else if (const WhileStmt *WS = dyn_cast<WhileStmt>(Loop)) + CS = dyn_cast<CompoundStmt>(WS->getBody()); + } + + PathDiagnosticEventPiece *p = + new PathDiagnosticEventPiece(L, + "Looping back to the head of the loop"); + + EB.addEdge(p->getLocation(), true); + PD.push_front(p); + + if (CS) { + PathDiagnosticLocation BL(CS->getRBracLoc(), + PDB.getSourceManager()); + BL = PathDiagnosticLocation(BL.asLocation()); + EB.addEdge(BL); + } + } + + if (Term) + EB.addContext(Term); + + break; + } + + if (const BlockEntrance *BE = dyn_cast<BlockEntrance>(&P)) { + if (const Stmt* S = BE->getFirstStmt()) { + if (IsControlFlowExpr(S)) { + // Add the proper context for '&&', '||', and '?'. + EB.addContext(S); + } + else + EB.addExtendedContext(PDB.getEnclosingStmtLocation(S).asStmt()); + } + + break; + } + } while (0); + + if (!NextNode) + continue; + + for (BugReporterContext::visitor_iterator I = PDB.visitor_begin(), + E = PDB.visitor_end(); I!=E; ++I) { + if (PathDiagnosticPiece* p = (*I)->VisitNode(N, NextNode, PDB)) { + const PathDiagnosticLocation &Loc = p->getLocation(); + EB.addEdge(Loc, true); + PD.push_front(p); + if (const Stmt *S = Loc.asStmt()) + EB.addExtendedContext(PDB.getEnclosingStmtLocation(S).asStmt()); + } + } + } +} + +//===----------------------------------------------------------------------===// +// Methods for BugType and subclasses. +//===----------------------------------------------------------------------===// +BugType::~BugType() { + // Free up the equivalence class objects. Observe that we get a pointer to + // the object first before incrementing the iterator, as destroying the + // node before doing so means we will read from freed memory. + for (iterator I = begin(), E = end(); I !=E; ) { + BugReportEquivClass *EQ = &*I; + ++I; + delete EQ; + } +} +void BugType::FlushReports(BugReporter &BR) {} + +//===----------------------------------------------------------------------===// +// Methods for BugReport and subclasses. +//===----------------------------------------------------------------------===// +BugReport::~BugReport() {} +RangedBugReport::~RangedBugReport() {} + +const Stmt* BugReport::getStmt() const { + ProgramPoint ProgP = EndNode->getLocation(); + const Stmt *S = NULL; + + if (BlockEntrance* BE = dyn_cast<BlockEntrance>(&ProgP)) { + CFGBlock &Exit = ProgP.getLocationContext()->getCFG()->getExit(); + if (BE->getBlock() == &Exit) + S = GetPreviousStmt(EndNode); + } + if (!S) + S = GetStmt(ProgP); + + return S; +} + +PathDiagnosticPiece* +BugReport::getEndPath(BugReporterContext& BRC, + const ExplodedNode* EndPathNode) { + + const Stmt* S = getStmt(); + + if (!S) + return NULL; + + const SourceRange *Beg, *End; + getRanges(Beg, End); + PathDiagnosticLocation L(S, BRC.getSourceManager()); + + // Only add the statement itself as a range if we didn't specify any + // special ranges for this report. + PathDiagnosticPiece* P = new PathDiagnosticEventPiece(L, getDescription(), + Beg == End); + + for (; Beg != End; ++Beg) + P->addRange(*Beg); + + return P; +} + +void BugReport::getRanges(const SourceRange*& beg, const SourceRange*& end) { + if (const Expr* E = dyn_cast_or_null<Expr>(getStmt())) { + R = E->getSourceRange(); + assert(R.isValid()); + beg = &R; + end = beg+1; + } + else + beg = end = 0; +} + +SourceLocation BugReport::getLocation() const { + if (EndNode) + if (const Stmt* S = GetCurrentOrPreviousStmt(EndNode)) { + // For member expressions, return the location of the '.' or '->'. + if (const MemberExpr *ME = dyn_cast<MemberExpr>(S)) + return ME->getMemberLoc(); + // For binary operators, return the location of the operator. + if (const BinaryOperator *B = dyn_cast<BinaryOperator>(S)) + return B->getOperatorLoc(); + + return S->getLocStart(); + } + + return FullSourceLoc(); +} + +PathDiagnosticPiece* BugReport::VisitNode(const ExplodedNode* N, + const ExplodedNode* PrevN, + BugReporterContext &BRC) { + return NULL; +} + +//===----------------------------------------------------------------------===// +// Methods for BugReporter and subclasses. +//===----------------------------------------------------------------------===// + +BugReportEquivClass::~BugReportEquivClass() { + for (iterator I=begin(), E=end(); I!=E; ++I) delete *I; +} + +GRBugReporter::~GRBugReporter() { } +BugReporterData::~BugReporterData() {} + +ExplodedGraph &GRBugReporter::getGraph() { return Eng.getGraph(); } + +GRStateManager& +GRBugReporter::getStateManager() { return Eng.getStateManager(); } + +BugReporter::~BugReporter() { FlushReports(); } + +void BugReporter::FlushReports() { + if (BugTypes.isEmpty()) + return; + + // First flush the warnings for each BugType. This may end up creating new + // warnings and new BugTypes. Because ImmutableSet is a functional data + // structure, we do not need to worry about the iterators being invalidated. + for (BugTypesTy::iterator I=BugTypes.begin(), E=BugTypes.end(); I!=E; ++I) + const_cast<BugType*>(*I)->FlushReports(*this); + + // Iterate through BugTypes a second time. BugTypes may have been updated + // with new BugType objects and new warnings. + for (BugTypesTy::iterator I=BugTypes.begin(), E=BugTypes.end(); I!=E; ++I) { + BugType *BT = const_cast<BugType*>(*I); + + typedef llvm::FoldingSet<BugReportEquivClass> SetTy; + SetTy& EQClasses = BT->EQClasses; + + for (SetTy::iterator EI=EQClasses.begin(), EE=EQClasses.end(); EI!=EE;++EI){ + BugReportEquivClass& EQ = *EI; + FlushReport(EQ); + } + + // Delete the BugType object. + delete BT; + } + + // Remove all references to the BugType objects. + BugTypes = F.GetEmptySet(); +} + +//===----------------------------------------------------------------------===// +// PathDiagnostics generation. +//===----------------------------------------------------------------------===// + +static std::pair<std::pair<ExplodedGraph*, NodeBackMap*>, + std::pair<ExplodedNode*, unsigned> > +MakeReportGraph(const ExplodedGraph* G, + const ExplodedNode** NStart, + const ExplodedNode** NEnd) { + + // Create the trimmed graph. It will contain the shortest paths from the + // error nodes to the root. In the new graph we should only have one + // error node unless there are two or more error nodes with the same minimum + // path length. + ExplodedGraph* GTrim; + InterExplodedGraphMap* NMap; + + llvm::DenseMap<const void*, const void*> InverseMap; + llvm::tie(GTrim, NMap) = G->Trim(NStart, NEnd, &InverseMap); + + // Create owning pointers for GTrim and NMap just to ensure that they are + // released when this function exists. + llvm::OwningPtr<ExplodedGraph> AutoReleaseGTrim(GTrim); + llvm::OwningPtr<InterExplodedGraphMap> AutoReleaseNMap(NMap); + + // Find the (first) error node in the trimmed graph. We just need to consult + // the node map (NMap) which maps from nodes in the original graph to nodes + // in the new graph. + + std::queue<const ExplodedNode*> WS; + typedef llvm::DenseMap<const ExplodedNode*, unsigned> IndexMapTy; + IndexMapTy IndexMap; + + for (const ExplodedNode** I = NStart; I != NEnd; ++I) + if (const ExplodedNode *N = NMap->getMappedNode(*I)) { + unsigned NodeIndex = (I - NStart) / sizeof(*I); + WS.push(N); + IndexMap[*I] = NodeIndex; + } + + assert(!WS.empty() && "No error node found in the trimmed graph."); + + // Create a new (third!) graph with a single path. This is the graph + // that will be returned to the caller. + ExplodedGraph *GNew = new ExplodedGraph(GTrim->getContext()); + + // Sometimes the trimmed graph can contain a cycle. Perform a reverse BFS + // to the root node, and then construct a new graph that contains only + // a single path. + llvm::DenseMap<const void*,unsigned> Visited; + + unsigned cnt = 0; + const ExplodedNode* Root = 0; + + while (!WS.empty()) { + const ExplodedNode* Node = WS.front(); + WS.pop(); + + if (Visited.find(Node) != Visited.end()) + continue; + + Visited[Node] = cnt++; + + if (Node->pred_empty()) { + Root = Node; + break; + } + + for (ExplodedNode::const_pred_iterator I=Node->pred_begin(), + E=Node->pred_end(); I!=E; ++I) + WS.push(*I); + } + + assert(Root); + + // Now walk from the root down the BFS path, always taking the successor + // with the lowest number. + ExplodedNode *Last = 0, *First = 0; + NodeBackMap *BM = new NodeBackMap(); + unsigned NodeIndex = 0; + + for ( const ExplodedNode *N = Root ;;) { + // Lookup the number associated with the current node. + llvm::DenseMap<const void*,unsigned>::iterator I = Visited.find(N); + assert(I != Visited.end()); + + // Create the equivalent node in the new graph with the same state + // and location. + ExplodedNode* NewN = GNew->getNode(N->getLocation(), N->getState()); + + // Store the mapping to the original node. + llvm::DenseMap<const void*, const void*>::iterator IMitr=InverseMap.find(N); + assert(IMitr != InverseMap.end() && "No mapping to original node."); + (*BM)[NewN] = (const ExplodedNode*) IMitr->second; + + // Link up the new node with the previous node. + if (Last) + NewN->addPredecessor(Last, *GNew); + + Last = NewN; + + // Are we at the final node? + IndexMapTy::iterator IMI = + IndexMap.find((const ExplodedNode*)(IMitr->second)); + if (IMI != IndexMap.end()) { + First = NewN; + NodeIndex = IMI->second; + break; + } + + // Find the next successor node. We choose the node that is marked + // with the lowest DFS number. + ExplodedNode::const_succ_iterator SI = N->succ_begin(); + ExplodedNode::const_succ_iterator SE = N->succ_end(); + N = 0; + + for (unsigned MinVal = 0; SI != SE; ++SI) { + + I = Visited.find(*SI); + + if (I == Visited.end()) + continue; + + if (!N || I->second < MinVal) { + N = *SI; + MinVal = I->second; + } + } + + assert(N); + } + + assert(First); + + return std::make_pair(std::make_pair(GNew, BM), + std::make_pair(First, NodeIndex)); +} + +/// CompactPathDiagnostic - This function postprocesses a PathDiagnostic object +/// and collapses PathDiagosticPieces that are expanded by macros. +static void CompactPathDiagnostic(PathDiagnostic &PD, const SourceManager& SM) { + typedef std::vector<std::pair<PathDiagnosticMacroPiece*, SourceLocation> > + MacroStackTy; + + typedef std::vector<PathDiagnosticPiece*> + PiecesTy; + + MacroStackTy MacroStack; + PiecesTy Pieces; + + for (PathDiagnostic::iterator I = PD.begin(), E = PD.end(); I!=E; ++I) { + // Get the location of the PathDiagnosticPiece. + const FullSourceLoc Loc = I->getLocation().asLocation(); + + // Determine the instantiation location, which is the location we group + // related PathDiagnosticPieces. + SourceLocation InstantiationLoc = Loc.isMacroID() ? + SM.getInstantiationLoc(Loc) : + SourceLocation(); + + if (Loc.isFileID()) { + MacroStack.clear(); + Pieces.push_back(&*I); + continue; + } + + assert(Loc.isMacroID()); + + // Is the PathDiagnosticPiece within the same macro group? + if (!MacroStack.empty() && InstantiationLoc == MacroStack.back().second) { + MacroStack.back().first->push_back(&*I); + continue; + } + + // We aren't in the same group. Are we descending into a new macro + // or are part of an old one? + PathDiagnosticMacroPiece *MacroGroup = 0; + + SourceLocation ParentInstantiationLoc = InstantiationLoc.isMacroID() ? + SM.getInstantiationLoc(Loc) : + SourceLocation(); + + // Walk the entire macro stack. + while (!MacroStack.empty()) { + if (InstantiationLoc == MacroStack.back().second) { + MacroGroup = MacroStack.back().first; + break; + } + + if (ParentInstantiationLoc == MacroStack.back().second) { + MacroGroup = MacroStack.back().first; + break; + } + + MacroStack.pop_back(); + } + + if (!MacroGroup || ParentInstantiationLoc == MacroStack.back().second) { + // Create a new macro group and add it to the stack. + PathDiagnosticMacroPiece *NewGroup = new PathDiagnosticMacroPiece(Loc); + + if (MacroGroup) + MacroGroup->push_back(NewGroup); + else { + assert(InstantiationLoc.isFileID()); + Pieces.push_back(NewGroup); + } + + MacroGroup = NewGroup; + MacroStack.push_back(std::make_pair(MacroGroup, InstantiationLoc)); + } + + // Finally, add the PathDiagnosticPiece to the group. + MacroGroup->push_back(&*I); + } + + // Now take the pieces and construct a new PathDiagnostic. + PD.resetPath(false); + + for (PiecesTy::iterator I=Pieces.begin(), E=Pieces.end(); I!=E; ++I) { + if (PathDiagnosticMacroPiece *MP=dyn_cast<PathDiagnosticMacroPiece>(*I)) + if (!MP->containsEvent()) { + delete MP; + continue; + } + + PD.push_back(*I); + } +} + +void GRBugReporter::GeneratePathDiagnostic(PathDiagnostic& PD, + BugReportEquivClass& EQ) { + + std::vector<const ExplodedNode*> Nodes; + + for (BugReportEquivClass::iterator I=EQ.begin(), E=EQ.end(); I!=E; ++I) { + const ExplodedNode* N = I->getEndNode(); + if (N) Nodes.push_back(N); + } + + if (Nodes.empty()) + return; + + // Construct a new graph that contains only a single path from the error + // node to a root. + const std::pair<std::pair<ExplodedGraph*, NodeBackMap*>, + std::pair<ExplodedNode*, unsigned> >& + GPair = MakeReportGraph(&getGraph(), &Nodes[0], &Nodes[0] + Nodes.size()); + + // Find the BugReport with the original location. + BugReport *R = 0; + unsigned i = 0; + for (BugReportEquivClass::iterator I=EQ.begin(), E=EQ.end(); I!=E; ++I, ++i) + if (i == GPair.second.second) { R = *I; break; } + + assert(R && "No original report found for sliced graph."); + + llvm::OwningPtr<ExplodedGraph> ReportGraph(GPair.first.first); + llvm::OwningPtr<NodeBackMap> BackMap(GPair.first.second); + const ExplodedNode *N = GPair.second.first; + + // Start building the path diagnostic... + PathDiagnosticBuilder PDB(*this, R, BackMap.get(), getPathDiagnosticClient()); + + if (PathDiagnosticPiece* Piece = R->getEndPath(PDB, N)) + PD.push_back(Piece); + else + return; + + // Register node visitors. + R->registerInitialVisitors(PDB, N); + bugreporter::registerNilReceiverVisitor(PDB); + + switch (PDB.getGenerationScheme()) { + case PathDiagnosticClient::Extensive: + GenerateExtensivePathDiagnostic(PD, PDB, N); + break; + case PathDiagnosticClient::Minimal: + GenerateMinimalPathDiagnostic(PD, PDB, N); + break; + } +} + +void BugReporter::Register(BugType *BT) { + BugTypes = F.Add(BugTypes, BT); +} + +void BugReporter::EmitReport(BugReport* R) { + // Compute the bug report's hash to determine its equivalence class. + llvm::FoldingSetNodeID ID; + R->Profile(ID); + + // Lookup the equivance class. If there isn't one, create it. + BugType& BT = R->getBugType(); + Register(&BT); + void *InsertPos; + BugReportEquivClass* EQ = BT.EQClasses.FindNodeOrInsertPos(ID, InsertPos); + + if (!EQ) { + EQ = new BugReportEquivClass(R); + BT.EQClasses.InsertNode(EQ, InsertPos); + } + else + EQ->AddReport(R); +} + + +//===----------------------------------------------------------------------===// +// Emitting reports in equivalence classes. +//===----------------------------------------------------------------------===// + +namespace { +struct FRIEC_WLItem { + const ExplodedNode *N; + ExplodedNode::const_succ_iterator I, E; + + FRIEC_WLItem(const ExplodedNode *n) + : N(n), I(N->succ_begin()), E(N->succ_end()) {} +}; +} + +static BugReport *FindReportInEquivalenceClass(BugReportEquivClass& EQ) { + BugReportEquivClass::iterator I = EQ.begin(), E = EQ.end(); + assert(I != E); + BugReport *R = *I; + BugType& BT = R->getBugType(); + + if (!BT.isSuppressOnSink()) + return R; + + // For bug reports that should be suppressed when all paths are post-dominated + // by a sink node, iterate through the reports in the equivalence class + // until we find one that isn't post-dominated (if one exists). We use a + // DFS traversal of the ExplodedGraph to find a non-sink node. We could write + // this as a recursive function, but we don't want to risk blowing out the + // stack for very long paths. + for (; I != E; ++I) { + R = *I; + const ExplodedNode *N = R->getEndNode(); + + if (!N) + continue; + + if (N->isSink()) { + assert(false && + "BugType::isSuppressSink() should not be 'true' for sink end nodes"); + return R; + } + + if (N->succ_empty()) + return R; + + // At this point we know that 'N' is not a sink and it has at least one + // successor. Use a DFS worklist to find a non-sink end-of-path node. + typedef FRIEC_WLItem WLItem; + typedef llvm::SmallVector<WLItem, 10> DFSWorkList; + llvm::DenseMap<const ExplodedNode *, unsigned> Visited; + + DFSWorkList WL; + WL.push_back(N); + Visited[N] = 1; + + while (!WL.empty()) { + WLItem &WI = WL.back(); + assert(!WI.N->succ_empty()); + + for (; WI.I != WI.E; ++WI.I) { + const ExplodedNode *Succ = *WI.I; + // End-of-path node? + if (Succ->succ_empty()) { + // If we found an end-of-path node that is not a sink, then return + // this report. + if (!Succ->isSink()) + return R; + + // Found a sink? Continue on to the next successor. + continue; + } + + // Mark the successor as visited. If it hasn't been explored, + // enqueue it to the DFS worklist. + unsigned &mark = Visited[Succ]; + if (!mark) { + mark = 1; + WL.push_back(Succ); + break; + } + } + + if (&WL.back() == &WI) + WL.pop_back(); + } + } + + // If we reach here, the end nodes for all reports in the equivalence + // class are post-dominated by a sink node. + return NULL; +} + + +//===----------------------------------------------------------------------===// +// DiagnosticCache. This is a hack to cache analyzer diagnostics. It +// uses global state, which eventually should go elsewhere. +//===----------------------------------------------------------------------===// +namespace { +class DiagCacheItem : public llvm::FoldingSetNode { + llvm::FoldingSetNodeID ID; +public: + DiagCacheItem(BugReport *R, PathDiagnostic *PD) { + ID.AddString(R->getBugType().getName()); + ID.AddString(R->getBugType().getCategory()); + ID.AddString(R->getDescription()); + ID.AddInteger(R->getLocation().getRawEncoding()); + PD->Profile(ID); + } + + void Profile(llvm::FoldingSetNodeID &id) { + id = ID; + } + + llvm::FoldingSetNodeID &getID() { return ID; } +}; +} + +static bool IsCachedDiagnostic(BugReport *R, PathDiagnostic *PD) { + // FIXME: Eventually this diagnostic cache should reside in something + // like AnalysisManager instead of being a static variable. This is + // really unsafe in the long term. + typedef llvm::FoldingSet<DiagCacheItem> DiagnosticCache; + static DiagnosticCache DC; + + void *InsertPos; + DiagCacheItem *Item = new DiagCacheItem(R, PD); + + if (DC.FindNodeOrInsertPos(Item->getID(), InsertPos)) { + delete Item; + return true; + } + + DC.InsertNode(Item, InsertPos); + return false; +} + +void BugReporter::FlushReport(BugReportEquivClass& EQ) { + BugReport *R = FindReportInEquivalenceClass(EQ); + + if (!R) + return; + + PathDiagnosticClient* PD = getPathDiagnosticClient(); + + // FIXME: Make sure we use the 'R' for the path that was actually used. + // Probably doesn't make a difference in practice. + BugType& BT = R->getBugType(); + + llvm::OwningPtr<PathDiagnostic> + D(new PathDiagnostic(R->getBugType().getName(), + !PD || PD->useVerboseDescription() + ? R->getDescription() : R->getShortDescription(), + BT.getCategory())); + + GeneratePathDiagnostic(*D.get(), EQ); + + if (IsCachedDiagnostic(R, D.get())) + return; + + // 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 summary diagnostic to the regular Diagnostics engine. + const SourceRange *Beg = 0, *End = 0; + R->getRanges(Beg, End); + Diagnostic& Diag = getDiagnostic(); + FullSourceLoc L(R->getLocation(), getSourceManager()); + + // Search the description for '%', as that will be interpretted as a + // format character by FormatDiagnostics. + llvm::StringRef desc = R->getShortDescription(); + unsigned ErrorDiag; + { + llvm::SmallString<512> TmpStr; + llvm::raw_svector_ostream Out(TmpStr); + for (llvm::StringRef::iterator I=desc.begin(), E=desc.end(); I!=E; ++I) + if (*I == '%') + Out << "%%"; + else + Out << *I; + + Out.flush(); + ErrorDiag = Diag.getCustomDiagID(Diagnostic::Warning, TmpStr); + } + + switch (End-Beg) { + default: assert(0 && "Don't handle this many ranges yet!"); + case 0: Diag.Report(L, ErrorDiag); break; + case 1: Diag.Report(L, ErrorDiag) << Beg[0]; break; + case 2: Diag.Report(L, ErrorDiag) << Beg[0] << Beg[1]; break; + case 3: Diag.Report(L, ErrorDiag) << Beg[0] << Beg[1] << Beg[2]; break; + } + + // Emit a full diagnostic for the path if we have a PathDiagnosticClient. + if (!PD) + return; + + if (D->empty()) { + PathDiagnosticPiece* piece = + new PathDiagnosticEventPiece(L, R->getDescription()); + + for ( ; Beg != End; ++Beg) piece->addRange(*Beg); + D->push_back(piece); + } + + PD->HandlePathDiagnostic(D.take()); +} + +void BugReporter::EmitBasicReport(llvm::StringRef name, llvm::StringRef str, + SourceLocation Loc, + SourceRange* RBeg, unsigned NumRanges) { + EmitBasicReport(name, "", str, Loc, RBeg, NumRanges); +} + +void BugReporter::EmitBasicReport(llvm::StringRef name, + llvm::StringRef category, + llvm::StringRef str, SourceLocation Loc, + SourceRange* RBeg, unsigned NumRanges) { + + // 'BT' will be owned by BugReporter as soon as we call 'EmitReport'. + BugType *BT = new BugType(name, category); + FullSourceLoc L = getContext().getFullLoc(Loc); + RangedBugReport *R = new DiagBugReport(*BT, str, L); + for ( ; NumRanges > 0 ; --NumRanges, ++RBeg) R->addRange(*RBeg); + EmitReport(R); +} |
