1 // BugReporter.cpp - Generate PathDiagnostics for Bugs ------------*- C++ -*--// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file defines BugReporter, a utility class for generating 11 // PathDiagnostics. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h" 16 #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h" 17 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h" 18 #include "clang/AST/ASTContext.h" 19 #include "clang/Analysis/CFG.h" 20 #include "clang/AST/DeclObjC.h" 21 #include "clang/AST/Expr.h" 22 #include "clang/AST/ParentMap.h" 23 #include "clang/AST/StmtObjC.h" 24 #include "clang/Basic/SourceManager.h" 25 #include "clang/Analysis/ProgramPoint.h" 26 #include "clang/StaticAnalyzer/Core/BugReporter/PathDiagnostic.h" 27 #include "llvm/Support/raw_ostream.h" 28 #include "llvm/ADT/DenseMap.h" 29 #include "llvm/ADT/SmallString.h" 30 #include "llvm/ADT/STLExtras.h" 31 #include "llvm/ADT/OwningPtr.h" 32 #include "llvm/ADT/IntrusiveRefCntPtr.h" 33 #include <queue> 34 35 using namespace clang; 36 using namespace ento; 37 38 BugReporterVisitor::~BugReporterVisitor() {} 39 40 void BugReporterContext::anchor() {} 41 42 //===----------------------------------------------------------------------===// 43 // Helper routines for walking the ExplodedGraph and fetching statements. 44 //===----------------------------------------------------------------------===// 45 46 static inline const Stmt *GetStmt(const ProgramPoint &P) { 47 if (const StmtPoint* SP = dyn_cast<StmtPoint>(&P)) 48 return SP->getStmt(); 49 else if (const BlockEdge *BE = dyn_cast<BlockEdge>(&P)) 50 return BE->getSrc()->getTerminator(); 51 else if (const CallEnter *CE = dyn_cast<CallEnter>(&P)) 52 return CE->getCallExpr(); 53 else if (const CallExitEnd *CEE = dyn_cast<CallExitEnd>(&P)) 54 return CEE->getCalleeContext()->getCallSite(); 55 56 return 0; 57 } 58 59 static inline const ExplodedNode* 60 GetPredecessorNode(const ExplodedNode *N) { 61 return N->pred_empty() ? NULL : *(N->pred_begin()); 62 } 63 64 static inline const ExplodedNode* 65 GetSuccessorNode(const ExplodedNode *N) { 66 return N->succ_empty() ? NULL : *(N->succ_begin()); 67 } 68 69 static const Stmt *GetPreviousStmt(const ExplodedNode *N) { 70 for (N = GetPredecessorNode(N); N; N = GetPredecessorNode(N)) 71 if (const Stmt *S = GetStmt(N->getLocation())) 72 return S; 73 74 return 0; 75 } 76 77 static const Stmt *GetNextStmt(const ExplodedNode *N) { 78 for (N = GetSuccessorNode(N); N; N = GetSuccessorNode(N)) 79 if (const Stmt *S = GetStmt(N->getLocation())) { 80 // Check if the statement is '?' or '&&'/'||'. These are "merges", 81 // not actual statement points. 82 switch (S->getStmtClass()) { 83 case Stmt::ChooseExprClass: 84 case Stmt::BinaryConditionalOperatorClass: continue; 85 case Stmt::ConditionalOperatorClass: continue; 86 case Stmt::BinaryOperatorClass: { 87 BinaryOperatorKind Op = cast<BinaryOperator>(S)->getOpcode(); 88 if (Op == BO_LAnd || Op == BO_LOr) 89 continue; 90 break; 91 } 92 default: 93 break; 94 } 95 return S; 96 } 97 98 return 0; 99 } 100 101 static inline const Stmt* 102 GetCurrentOrPreviousStmt(const ExplodedNode *N) { 103 if (const Stmt *S = GetStmt(N->getLocation())) 104 return S; 105 106 return GetPreviousStmt(N); 107 } 108 109 static inline const Stmt* 110 GetCurrentOrNextStmt(const ExplodedNode *N) { 111 if (const Stmt *S = GetStmt(N->getLocation())) 112 return S; 113 114 return GetNextStmt(N); 115 } 116 117 //===----------------------------------------------------------------------===// 118 // Diagnostic cleanup. 119 //===----------------------------------------------------------------------===// 120 121 /// Recursively scan through a path and prune out calls and macros pieces 122 /// that aren't needed. Return true if afterwards the path contains 123 /// "interesting stuff" which means it should be pruned from the parent path. 124 bool BugReporter::RemoveUneededCalls(PathPieces &pieces, BugReport *R) { 125 bool containsSomethingInteresting = false; 126 const unsigned N = pieces.size(); 127 128 for (unsigned i = 0 ; i < N ; ++i) { 129 // Remove the front piece from the path. If it is still something we 130 // want to keep once we are done, we will push it back on the end. 131 IntrusiveRefCntPtr<PathDiagnosticPiece> piece(pieces.front()); 132 pieces.pop_front(); 133 134 switch (piece->getKind()) { 135 case PathDiagnosticPiece::Call: { 136 PathDiagnosticCallPiece *call = cast<PathDiagnosticCallPiece>(piece); 137 // Check if the location context is interesting. 138 assert(LocationContextMap.count(call)); 139 if (R->isInteresting(LocationContextMap[call])) { 140 containsSomethingInteresting = true; 141 break; 142 } 143 // Recursively clean out the subclass. Keep this call around if 144 // it contains any informative diagnostics. 145 if (!RemoveUneededCalls(call->path, R)) 146 continue; 147 containsSomethingInteresting = true; 148 break; 149 } 150 case PathDiagnosticPiece::Macro: { 151 PathDiagnosticMacroPiece *macro = cast<PathDiagnosticMacroPiece>(piece); 152 if (!RemoveUneededCalls(macro->subPieces, R)) 153 continue; 154 containsSomethingInteresting = true; 155 break; 156 } 157 case PathDiagnosticPiece::Event: { 158 PathDiagnosticEventPiece *event = cast<PathDiagnosticEventPiece>(piece); 159 // We never throw away an event, but we do throw it away wholesale 160 // as part of a path if we throw the entire path away. 161 containsSomethingInteresting |= !event->isPrunable(); 162 break; 163 } 164 case PathDiagnosticPiece::ControlFlow: 165 break; 166 } 167 168 pieces.push_back(piece); 169 } 170 171 return containsSomethingInteresting; 172 } 173 174 //===----------------------------------------------------------------------===// 175 // PathDiagnosticBuilder and its associated routines and helper objects. 176 //===----------------------------------------------------------------------===// 177 178 typedef llvm::DenseMap<const ExplodedNode*, 179 const ExplodedNode*> NodeBackMap; 180 181 namespace { 182 class NodeMapClosure : public BugReport::NodeResolver { 183 NodeBackMap& M; 184 public: 185 NodeMapClosure(NodeBackMap *m) : M(*m) {} 186 ~NodeMapClosure() {} 187 188 const ExplodedNode *getOriginalNode(const ExplodedNode *N) { 189 NodeBackMap::iterator I = M.find(N); 190 return I == M.end() ? 0 : I->second; 191 } 192 }; 193 194 class PathDiagnosticBuilder : public BugReporterContext { 195 BugReport *R; 196 PathDiagnosticConsumer *PDC; 197 OwningPtr<ParentMap> PM; 198 NodeMapClosure NMC; 199 public: 200 const LocationContext *LC; 201 202 PathDiagnosticBuilder(GRBugReporter &br, 203 BugReport *r, NodeBackMap *Backmap, 204 PathDiagnosticConsumer *pdc) 205 : BugReporterContext(br), 206 R(r), PDC(pdc), NMC(Backmap), LC(r->getErrorNode()->getLocationContext()) 207 {} 208 209 PathDiagnosticLocation ExecutionContinues(const ExplodedNode *N); 210 211 PathDiagnosticLocation ExecutionContinues(llvm::raw_string_ostream &os, 212 const ExplodedNode *N); 213 214 BugReport *getBugReport() { return R; } 215 216 Decl const &getCodeDecl() { return R->getErrorNode()->getCodeDecl(); } 217 218 ParentMap& getParentMap() { return LC->getParentMap(); } 219 220 const Stmt *getParent(const Stmt *S) { 221 return getParentMap().getParent(S); 222 } 223 224 virtual NodeMapClosure& getNodeResolver() { return NMC; } 225 226 PathDiagnosticLocation getEnclosingStmtLocation(const Stmt *S); 227 228 PathDiagnosticConsumer::PathGenerationScheme getGenerationScheme() const { 229 return PDC ? PDC->getGenerationScheme() : PathDiagnosticConsumer::Extensive; 230 } 231 232 bool supportsLogicalOpControlFlow() const { 233 return PDC ? PDC->supportsLogicalOpControlFlow() : true; 234 } 235 }; 236 } // end anonymous namespace 237 238 PathDiagnosticLocation 239 PathDiagnosticBuilder::ExecutionContinues(const ExplodedNode *N) { 240 if (const Stmt *S = GetNextStmt(N)) 241 return PathDiagnosticLocation(S, getSourceManager(), LC); 242 243 return PathDiagnosticLocation::createDeclEnd(N->getLocationContext(), 244 getSourceManager()); 245 } 246 247 PathDiagnosticLocation 248 PathDiagnosticBuilder::ExecutionContinues(llvm::raw_string_ostream &os, 249 const ExplodedNode *N) { 250 251 // Slow, but probably doesn't matter. 252 if (os.str().empty()) 253 os << ' '; 254 255 const PathDiagnosticLocation &Loc = ExecutionContinues(N); 256 257 if (Loc.asStmt()) 258 os << "Execution continues on line " 259 << getSourceManager().getExpansionLineNumber(Loc.asLocation()) 260 << '.'; 261 else { 262 os << "Execution jumps to the end of the "; 263 const Decl *D = N->getLocationContext()->getDecl(); 264 if (isa<ObjCMethodDecl>(D)) 265 os << "method"; 266 else if (isa<FunctionDecl>(D)) 267 os << "function"; 268 else { 269 assert(isa<BlockDecl>(D)); 270 os << "anonymous block"; 271 } 272 os << '.'; 273 } 274 275 return Loc; 276 } 277 278 static bool IsNested(const Stmt *S, ParentMap &PM) { 279 if (isa<Expr>(S) && PM.isConsumedExpr(cast<Expr>(S))) 280 return true; 281 282 const Stmt *Parent = PM.getParentIgnoreParens(S); 283 284 if (Parent) 285 switch (Parent->getStmtClass()) { 286 case Stmt::ForStmtClass: 287 case Stmt::DoStmtClass: 288 case Stmt::WhileStmtClass: 289 return true; 290 default: 291 break; 292 } 293 294 return false; 295 } 296 297 PathDiagnosticLocation 298 PathDiagnosticBuilder::getEnclosingStmtLocation(const Stmt *S) { 299 assert(S && "Null Stmt *passed to getEnclosingStmtLocation"); 300 ParentMap &P = getParentMap(); 301 SourceManager &SMgr = getSourceManager(); 302 303 while (IsNested(S, P)) { 304 const Stmt *Parent = P.getParentIgnoreParens(S); 305 306 if (!Parent) 307 break; 308 309 switch (Parent->getStmtClass()) { 310 case Stmt::BinaryOperatorClass: { 311 const BinaryOperator *B = cast<BinaryOperator>(Parent); 312 if (B->isLogicalOp()) 313 return PathDiagnosticLocation(S, SMgr, LC); 314 break; 315 } 316 case Stmt::CompoundStmtClass: 317 case Stmt::StmtExprClass: 318 return PathDiagnosticLocation(S, SMgr, LC); 319 case Stmt::ChooseExprClass: 320 // Similar to '?' if we are referring to condition, just have the edge 321 // point to the entire choose expression. 322 if (cast<ChooseExpr>(Parent)->getCond() == S) 323 return PathDiagnosticLocation(Parent, SMgr, LC); 324 else 325 return PathDiagnosticLocation(S, SMgr, LC); 326 case Stmt::BinaryConditionalOperatorClass: 327 case Stmt::ConditionalOperatorClass: 328 // For '?', if we are referring to condition, just have the edge point 329 // to the entire '?' expression. 330 if (cast<AbstractConditionalOperator>(Parent)->getCond() == S) 331 return PathDiagnosticLocation(Parent, SMgr, LC); 332 else 333 return PathDiagnosticLocation(S, SMgr, LC); 334 case Stmt::DoStmtClass: 335 return PathDiagnosticLocation(S, SMgr, LC); 336 case Stmt::ForStmtClass: 337 if (cast<ForStmt>(Parent)->getBody() == S) 338 return PathDiagnosticLocation(S, SMgr, LC); 339 break; 340 case Stmt::IfStmtClass: 341 if (cast<IfStmt>(Parent)->getCond() != S) 342 return PathDiagnosticLocation(S, SMgr, LC); 343 break; 344 case Stmt::ObjCForCollectionStmtClass: 345 if (cast<ObjCForCollectionStmt>(Parent)->getBody() == S) 346 return PathDiagnosticLocation(S, SMgr, LC); 347 break; 348 case Stmt::WhileStmtClass: 349 if (cast<WhileStmt>(Parent)->getCond() != S) 350 return PathDiagnosticLocation(S, SMgr, LC); 351 break; 352 default: 353 break; 354 } 355 356 S = Parent; 357 } 358 359 assert(S && "Cannot have null Stmt for PathDiagnosticLocation"); 360 361 // Special case: DeclStmts can appear in for statement declarations, in which 362 // case the ForStmt is the context. 363 if (isa<DeclStmt>(S)) { 364 if (const Stmt *Parent = P.getParent(S)) { 365 switch (Parent->getStmtClass()) { 366 case Stmt::ForStmtClass: 367 case Stmt::ObjCForCollectionStmtClass: 368 return PathDiagnosticLocation(Parent, SMgr, LC); 369 default: 370 break; 371 } 372 } 373 } 374 else if (isa<BinaryOperator>(S)) { 375 // Special case: the binary operator represents the initialization 376 // code in a for statement (this can happen when the variable being 377 // initialized is an old variable. 378 if (const ForStmt *FS = 379 dyn_cast_or_null<ForStmt>(P.getParentIgnoreParens(S))) { 380 if (FS->getInit() == S) 381 return PathDiagnosticLocation(FS, SMgr, LC); 382 } 383 } 384 385 return PathDiagnosticLocation(S, SMgr, LC); 386 } 387 388 //===----------------------------------------------------------------------===// 389 // "Minimal" path diagnostic generation algorithm. 390 //===----------------------------------------------------------------------===// 391 typedef std::pair<PathDiagnosticCallPiece*, const ExplodedNode*> StackDiagPair; 392 typedef SmallVector<StackDiagPair, 6> StackDiagVector; 393 394 static void updateStackPiecesWithMessage(PathDiagnosticPiece *P, 395 StackDiagVector &CallStack) { 396 // If the piece contains a special message, add it to all the call 397 // pieces on the active stack. 398 if (PathDiagnosticEventPiece *ep = 399 dyn_cast<PathDiagnosticEventPiece>(P)) { 400 401 if (ep->hasCallStackHint()) 402 for (StackDiagVector::iterator I = CallStack.begin(), 403 E = CallStack.end(); I != E; ++I) { 404 PathDiagnosticCallPiece *CP = I->first; 405 const ExplodedNode *N = I->second; 406 std::string stackMsg = ep->getCallStackMessage(N); 407 408 // The last message on the path to final bug is the most important 409 // one. Since we traverse the path backwards, do not add the message 410 // if one has been previously added. 411 if (!CP->hasCallStackMessage()) 412 CP->setCallStackMessage(stackMsg); 413 } 414 } 415 } 416 417 static void CompactPathDiagnostic(PathPieces &path, const SourceManager& SM); 418 419 static void GenerateMinimalPathDiagnostic(PathDiagnostic& PD, 420 PathDiagnosticBuilder &PDB, 421 const ExplodedNode *N, 422 ArrayRef<BugReporterVisitor *> visitors) { 423 424 SourceManager& SMgr = PDB.getSourceManager(); 425 const LocationContext *LC = PDB.LC; 426 const ExplodedNode *NextNode = N->pred_empty() 427 ? NULL : *(N->pred_begin()); 428 429 StackDiagVector CallStack; 430 431 while (NextNode) { 432 N = NextNode; 433 PDB.LC = N->getLocationContext(); 434 NextNode = GetPredecessorNode(N); 435 436 ProgramPoint P = N->getLocation(); 437 438 do { 439 if (const CallExitEnd *CE = dyn_cast<CallExitEnd>(&P)) { 440 PathDiagnosticCallPiece *C = 441 PathDiagnosticCallPiece::construct(N, *CE, SMgr); 442 GRBugReporter& BR = PDB.getBugReporter(); 443 BR.addCallPieceLocationContextPair(C, CE->getCalleeContext()); 444 PD.getActivePath().push_front(C); 445 PD.pushActivePath(&C->path); 446 CallStack.push_back(StackDiagPair(C, N)); 447 break; 448 } 449 450 if (const CallEnter *CE = dyn_cast<CallEnter>(&P)) { 451 // Flush all locations, and pop the active path. 452 bool VisitedEntireCall = PD.isWithinCall(); 453 PD.popActivePath(); 454 455 // Either we just added a bunch of stuff to the top-level path, or 456 // we have a previous CallExitEnd. If the former, it means that the 457 // path terminated within a function call. We must then take the 458 // current contents of the active path and place it within 459 // a new PathDiagnosticCallPiece. 460 PathDiagnosticCallPiece *C; 461 if (VisitedEntireCall) { 462 C = cast<PathDiagnosticCallPiece>(PD.getActivePath().front()); 463 } else { 464 const Decl *Caller = CE->getLocationContext()->getDecl(); 465 C = PathDiagnosticCallPiece::construct(PD.getActivePath(), Caller); 466 GRBugReporter& BR = PDB.getBugReporter(); 467 BR.addCallPieceLocationContextPair(C, CE->getCalleeContext()); 468 } 469 470 C->setCallee(*CE, SMgr); 471 if (!CallStack.empty()) { 472 assert(CallStack.back().first == C); 473 CallStack.pop_back(); 474 } 475 break; 476 } 477 478 if (const BlockEdge *BE = dyn_cast<BlockEdge>(&P)) { 479 const CFGBlock *Src = BE->getSrc(); 480 const CFGBlock *Dst = BE->getDst(); 481 const Stmt *T = Src->getTerminator(); 482 483 if (!T) 484 break; 485 486 PathDiagnosticLocation Start = 487 PathDiagnosticLocation::createBegin(T, SMgr, 488 N->getLocationContext()); 489 490 switch (T->getStmtClass()) { 491 default: 492 break; 493 494 case Stmt::GotoStmtClass: 495 case Stmt::IndirectGotoStmtClass: { 496 const Stmt *S = GetNextStmt(N); 497 498 if (!S) 499 break; 500 501 std::string sbuf; 502 llvm::raw_string_ostream os(sbuf); 503 const PathDiagnosticLocation &End = PDB.getEnclosingStmtLocation(S); 504 505 os << "Control jumps to line " 506 << End.asLocation().getExpansionLineNumber(); 507 PD.getActivePath().push_front(new PathDiagnosticControlFlowPiece( 508 Start, End, os.str())); 509 break; 510 } 511 512 case Stmt::SwitchStmtClass: { 513 // Figure out what case arm we took. 514 std::string sbuf; 515 llvm::raw_string_ostream os(sbuf); 516 517 if (const Stmt *S = Dst->getLabel()) { 518 PathDiagnosticLocation End(S, SMgr, LC); 519 520 switch (S->getStmtClass()) { 521 default: 522 os << "No cases match in the switch statement. " 523 "Control jumps to line " 524 << End.asLocation().getExpansionLineNumber(); 525 break; 526 case Stmt::DefaultStmtClass: 527 os << "Control jumps to the 'default' case at line " 528 << End.asLocation().getExpansionLineNumber(); 529 break; 530 531 case Stmt::CaseStmtClass: { 532 os << "Control jumps to 'case "; 533 const CaseStmt *Case = cast<CaseStmt>(S); 534 const Expr *LHS = Case->getLHS()->IgnoreParenCasts(); 535 536 // Determine if it is an enum. 537 bool GetRawInt = true; 538 539 if (const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(LHS)) { 540 // FIXME: Maybe this should be an assertion. Are there cases 541 // were it is not an EnumConstantDecl? 542 const EnumConstantDecl *D = 543 dyn_cast<EnumConstantDecl>(DR->getDecl()); 544 545 if (D) { 546 GetRawInt = false; 547 os << *D; 548 } 549 } 550 551 if (GetRawInt) 552 os << LHS->EvaluateKnownConstInt(PDB.getASTContext()); 553 554 os << ":' at line " 555 << End.asLocation().getExpansionLineNumber(); 556 break; 557 } 558 } 559 PD.getActivePath().push_front(new PathDiagnosticControlFlowPiece( 560 Start, End, os.str())); 561 } 562 else { 563 os << "'Default' branch taken. "; 564 const PathDiagnosticLocation &End = PDB.ExecutionContinues(os, N); 565 PD.getActivePath().push_front(new PathDiagnosticControlFlowPiece( 566 Start, End, os.str())); 567 } 568 569 break; 570 } 571 572 case Stmt::BreakStmtClass: 573 case Stmt::ContinueStmtClass: { 574 std::string sbuf; 575 llvm::raw_string_ostream os(sbuf); 576 PathDiagnosticLocation End = PDB.ExecutionContinues(os, N); 577 PD.getActivePath().push_front(new PathDiagnosticControlFlowPiece( 578 Start, End, os.str())); 579 break; 580 } 581 582 // Determine control-flow for ternary '?'. 583 case Stmt::BinaryConditionalOperatorClass: 584 case Stmt::ConditionalOperatorClass: { 585 std::string sbuf; 586 llvm::raw_string_ostream os(sbuf); 587 os << "'?' condition is "; 588 589 if (*(Src->succ_begin()+1) == Dst) 590 os << "false"; 591 else 592 os << "true"; 593 594 PathDiagnosticLocation End = PDB.ExecutionContinues(N); 595 596 if (const Stmt *S = End.asStmt()) 597 End = PDB.getEnclosingStmtLocation(S); 598 599 PD.getActivePath().push_front(new PathDiagnosticControlFlowPiece( 600 Start, End, os.str())); 601 break; 602 } 603 604 // Determine control-flow for short-circuited '&&' and '||'. 605 case Stmt::BinaryOperatorClass: { 606 if (!PDB.supportsLogicalOpControlFlow()) 607 break; 608 609 const BinaryOperator *B = cast<BinaryOperator>(T); 610 std::string sbuf; 611 llvm::raw_string_ostream os(sbuf); 612 os << "Left side of '"; 613 614 if (B->getOpcode() == BO_LAnd) { 615 os << "&&" << "' is "; 616 617 if (*(Src->succ_begin()+1) == Dst) { 618 os << "false"; 619 PathDiagnosticLocation End(B->getLHS(), SMgr, LC); 620 PathDiagnosticLocation Start = 621 PathDiagnosticLocation::createOperatorLoc(B, SMgr); 622 PD.getActivePath().push_front(new PathDiagnosticControlFlowPiece( 623 Start, End, os.str())); 624 } 625 else { 626 os << "true"; 627 PathDiagnosticLocation Start(B->getLHS(), SMgr, LC); 628 PathDiagnosticLocation End = PDB.ExecutionContinues(N); 629 PD.getActivePath().push_front(new PathDiagnosticControlFlowPiece( 630 Start, End, os.str())); 631 } 632 } 633 else { 634 assert(B->getOpcode() == BO_LOr); 635 os << "||" << "' is "; 636 637 if (*(Src->succ_begin()+1) == Dst) { 638 os << "false"; 639 PathDiagnosticLocation Start(B->getLHS(), SMgr, LC); 640 PathDiagnosticLocation End = PDB.ExecutionContinues(N); 641 PD.getActivePath().push_front(new PathDiagnosticControlFlowPiece( 642 Start, End, os.str())); 643 } 644 else { 645 os << "true"; 646 PathDiagnosticLocation End(B->getLHS(), SMgr, LC); 647 PathDiagnosticLocation Start = 648 PathDiagnosticLocation::createOperatorLoc(B, SMgr); 649 PD.getActivePath().push_front(new PathDiagnosticControlFlowPiece( 650 Start, End, os.str())); 651 } 652 } 653 654 break; 655 } 656 657 case Stmt::DoStmtClass: { 658 if (*(Src->succ_begin()) == Dst) { 659 std::string sbuf; 660 llvm::raw_string_ostream os(sbuf); 661 662 os << "Loop condition is true. "; 663 PathDiagnosticLocation End = PDB.ExecutionContinues(os, N); 664 665 if (const Stmt *S = End.asStmt()) 666 End = PDB.getEnclosingStmtLocation(S); 667 668 PD.getActivePath().push_front(new PathDiagnosticControlFlowPiece( 669 Start, End, os.str())); 670 } 671 else { 672 PathDiagnosticLocation End = PDB.ExecutionContinues(N); 673 674 if (const Stmt *S = End.asStmt()) 675 End = PDB.getEnclosingStmtLocation(S); 676 677 PD.getActivePath().push_front(new PathDiagnosticControlFlowPiece( 678 Start, End, "Loop condition is false. Exiting loop")); 679 } 680 681 break; 682 } 683 684 case Stmt::WhileStmtClass: 685 case Stmt::ForStmtClass: { 686 if (*(Src->succ_begin()+1) == Dst) { 687 std::string sbuf; 688 llvm::raw_string_ostream os(sbuf); 689 690 os << "Loop condition is false. "; 691 PathDiagnosticLocation End = PDB.ExecutionContinues(os, N); 692 if (const Stmt *S = End.asStmt()) 693 End = PDB.getEnclosingStmtLocation(S); 694 695 PD.getActivePath().push_front(new PathDiagnosticControlFlowPiece( 696 Start, End, os.str())); 697 } 698 else { 699 PathDiagnosticLocation End = PDB.ExecutionContinues(N); 700 if (const Stmt *S = End.asStmt()) 701 End = PDB.getEnclosingStmtLocation(S); 702 703 PD.getActivePath().push_front(new PathDiagnosticControlFlowPiece( 704 Start, End, "Loop condition is true. Entering loop body")); 705 } 706 707 break; 708 } 709 710 case Stmt::IfStmtClass: { 711 PathDiagnosticLocation End = PDB.ExecutionContinues(N); 712 713 if (const Stmt *S = End.asStmt()) 714 End = PDB.getEnclosingStmtLocation(S); 715 716 if (*(Src->succ_begin()+1) == Dst) 717 PD.getActivePath().push_front(new PathDiagnosticControlFlowPiece( 718 Start, End, "Taking false branch")); 719 else 720 PD.getActivePath().push_front(new PathDiagnosticControlFlowPiece( 721 Start, End, "Taking true branch")); 722 723 break; 724 } 725 } 726 } 727 } while(0); 728 729 if (NextNode) { 730 // Add diagnostic pieces from custom visitors. 731 BugReport *R = PDB.getBugReport(); 732 for (ArrayRef<BugReporterVisitor *>::iterator I = visitors.begin(), 733 E = visitors.end(); 734 I != E; ++I) { 735 if (PathDiagnosticPiece *p = (*I)->VisitNode(N, NextNode, PDB, *R)) { 736 PD.getActivePath().push_front(p); 737 updateStackPiecesWithMessage(p, CallStack); 738 } 739 } 740 } 741 } 742 743 // After constructing the full PathDiagnostic, do a pass over it to compact 744 // PathDiagnosticPieces that occur within a macro. 745 CompactPathDiagnostic(PD.getMutablePieces(), PDB.getSourceManager()); 746 } 747 748 //===----------------------------------------------------------------------===// 749 // "Extensive" PathDiagnostic generation. 750 //===----------------------------------------------------------------------===// 751 752 static bool IsControlFlowExpr(const Stmt *S) { 753 const Expr *E = dyn_cast<Expr>(S); 754 755 if (!E) 756 return false; 757 758 E = E->IgnoreParenCasts(); 759 760 if (isa<AbstractConditionalOperator>(E)) 761 return true; 762 763 if (const BinaryOperator *B = dyn_cast<BinaryOperator>(E)) 764 if (B->isLogicalOp()) 765 return true; 766 767 return false; 768 } 769 770 namespace { 771 class ContextLocation : public PathDiagnosticLocation { 772 bool IsDead; 773 public: 774 ContextLocation(const PathDiagnosticLocation &L, bool isdead = false) 775 : PathDiagnosticLocation(L), IsDead(isdead) {} 776 777 void markDead() { IsDead = true; } 778 bool isDead() const { return IsDead; } 779 }; 780 781 class EdgeBuilder { 782 std::vector<ContextLocation> CLocs; 783 typedef std::vector<ContextLocation>::iterator iterator; 784 PathDiagnostic &PD; 785 PathDiagnosticBuilder &PDB; 786 PathDiagnosticLocation PrevLoc; 787 788 bool IsConsumedExpr(const PathDiagnosticLocation &L); 789 790 bool containsLocation(const PathDiagnosticLocation &Container, 791 const PathDiagnosticLocation &Containee); 792 793 PathDiagnosticLocation getContextLocation(const PathDiagnosticLocation &L); 794 795 PathDiagnosticLocation cleanUpLocation(PathDiagnosticLocation L, 796 bool firstCharOnly = false) { 797 if (const Stmt *S = L.asStmt()) { 798 const Stmt *Original = S; 799 while (1) { 800 // Adjust the location for some expressions that are best referenced 801 // by one of their subexpressions. 802 switch (S->getStmtClass()) { 803 default: 804 break; 805 case Stmt::ParenExprClass: 806 case Stmt::GenericSelectionExprClass: 807 S = cast<Expr>(S)->IgnoreParens(); 808 firstCharOnly = true; 809 continue; 810 case Stmt::BinaryConditionalOperatorClass: 811 case Stmt::ConditionalOperatorClass: 812 S = cast<AbstractConditionalOperator>(S)->getCond(); 813 firstCharOnly = true; 814 continue; 815 case Stmt::ChooseExprClass: 816 S = cast<ChooseExpr>(S)->getCond(); 817 firstCharOnly = true; 818 continue; 819 case Stmt::BinaryOperatorClass: 820 S = cast<BinaryOperator>(S)->getLHS(); 821 firstCharOnly = true; 822 continue; 823 } 824 825 break; 826 } 827 828 if (S != Original) 829 L = PathDiagnosticLocation(S, L.getManager(), PDB.LC); 830 } 831 832 if (firstCharOnly) 833 L = PathDiagnosticLocation::createSingleLocation(L); 834 835 return L; 836 } 837 838 void popLocation() { 839 if (!CLocs.back().isDead() && CLocs.back().asLocation().isFileID()) { 840 // For contexts, we only one the first character as the range. 841 rawAddEdge(cleanUpLocation(CLocs.back(), true)); 842 } 843 CLocs.pop_back(); 844 } 845 846 public: 847 EdgeBuilder(PathDiagnostic &pd, PathDiagnosticBuilder &pdb) 848 : PD(pd), PDB(pdb) { 849 850 // If the PathDiagnostic already has pieces, add the enclosing statement 851 // of the first piece as a context as well. 852 if (!PD.path.empty()) { 853 PrevLoc = (*PD.path.begin())->getLocation(); 854 855 if (const Stmt *S = PrevLoc.asStmt()) 856 addExtendedContext(PDB.getEnclosingStmtLocation(S).asStmt()); 857 } 858 } 859 860 ~EdgeBuilder() { 861 while (!CLocs.empty()) popLocation(); 862 863 // Finally, add an initial edge from the start location of the first 864 // statement (if it doesn't already exist). 865 PathDiagnosticLocation L = PathDiagnosticLocation::createDeclBegin( 866 PDB.LC, 867 PDB.getSourceManager()); 868 if (L.isValid()) 869 rawAddEdge(L); 870 } 871 872 void flushLocations() { 873 while (!CLocs.empty()) 874 popLocation(); 875 PrevLoc = PathDiagnosticLocation(); 876 } 877 878 void addEdge(PathDiagnosticLocation NewLoc, bool alwaysAdd = false); 879 880 void rawAddEdge(PathDiagnosticLocation NewLoc); 881 882 void addContext(const Stmt *S); 883 void addContext(const PathDiagnosticLocation &L); 884 void addExtendedContext(const Stmt *S); 885 }; 886 } // end anonymous namespace 887 888 889 PathDiagnosticLocation 890 EdgeBuilder::getContextLocation(const PathDiagnosticLocation &L) { 891 if (const Stmt *S = L.asStmt()) { 892 if (IsControlFlowExpr(S)) 893 return L; 894 895 return PDB.getEnclosingStmtLocation(S); 896 } 897 898 return L; 899 } 900 901 bool EdgeBuilder::containsLocation(const PathDiagnosticLocation &Container, 902 const PathDiagnosticLocation &Containee) { 903 904 if (Container == Containee) 905 return true; 906 907 if (Container.asDecl()) 908 return true; 909 910 if (const Stmt *S = Containee.asStmt()) 911 if (const Stmt *ContainerS = Container.asStmt()) { 912 while (S) { 913 if (S == ContainerS) 914 return true; 915 S = PDB.getParent(S); 916 } 917 return false; 918 } 919 920 // Less accurate: compare using source ranges. 921 SourceRange ContainerR = Container.asRange(); 922 SourceRange ContaineeR = Containee.asRange(); 923 924 SourceManager &SM = PDB.getSourceManager(); 925 SourceLocation ContainerRBeg = SM.getExpansionLoc(ContainerR.getBegin()); 926 SourceLocation ContainerREnd = SM.getExpansionLoc(ContainerR.getEnd()); 927 SourceLocation ContaineeRBeg = SM.getExpansionLoc(ContaineeR.getBegin()); 928 SourceLocation ContaineeREnd = SM.getExpansionLoc(ContaineeR.getEnd()); 929 930 unsigned ContainerBegLine = SM.getExpansionLineNumber(ContainerRBeg); 931 unsigned ContainerEndLine = SM.getExpansionLineNumber(ContainerREnd); 932 unsigned ContaineeBegLine = SM.getExpansionLineNumber(ContaineeRBeg); 933 unsigned ContaineeEndLine = SM.getExpansionLineNumber(ContaineeREnd); 934 935 assert(ContainerBegLine <= ContainerEndLine); 936 assert(ContaineeBegLine <= ContaineeEndLine); 937 938 return (ContainerBegLine <= ContaineeBegLine && 939 ContainerEndLine >= ContaineeEndLine && 940 (ContainerBegLine != ContaineeBegLine || 941 SM.getExpansionColumnNumber(ContainerRBeg) <= 942 SM.getExpansionColumnNumber(ContaineeRBeg)) && 943 (ContainerEndLine != ContaineeEndLine || 944 SM.getExpansionColumnNumber(ContainerREnd) >= 945 SM.getExpansionColumnNumber(ContaineeREnd))); 946 } 947 948 void EdgeBuilder::rawAddEdge(PathDiagnosticLocation NewLoc) { 949 if (!PrevLoc.isValid()) { 950 PrevLoc = NewLoc; 951 return; 952 } 953 954 const PathDiagnosticLocation &NewLocClean = cleanUpLocation(NewLoc); 955 const PathDiagnosticLocation &PrevLocClean = cleanUpLocation(PrevLoc); 956 957 if (NewLocClean.asLocation() == PrevLocClean.asLocation()) 958 return; 959 960 // FIXME: Ignore intra-macro edges for now. 961 if (NewLocClean.asLocation().getExpansionLoc() == 962 PrevLocClean.asLocation().getExpansionLoc()) 963 return; 964 965 PD.getActivePath().push_front(new PathDiagnosticControlFlowPiece(NewLocClean, PrevLocClean)); 966 PrevLoc = NewLoc; 967 } 968 969 void EdgeBuilder::addEdge(PathDiagnosticLocation NewLoc, bool alwaysAdd) { 970 971 if (!alwaysAdd && NewLoc.asLocation().isMacroID()) 972 return; 973 974 const PathDiagnosticLocation &CLoc = getContextLocation(NewLoc); 975 976 while (!CLocs.empty()) { 977 ContextLocation &TopContextLoc = CLocs.back(); 978 979 // Is the top location context the same as the one for the new location? 980 if (TopContextLoc == CLoc) { 981 if (alwaysAdd) { 982 if (IsConsumedExpr(TopContextLoc) && 983 !IsControlFlowExpr(TopContextLoc.asStmt())) 984 TopContextLoc.markDead(); 985 986 rawAddEdge(NewLoc); 987 } 988 989 return; 990 } 991 992 if (containsLocation(TopContextLoc, CLoc)) { 993 if (alwaysAdd) { 994 rawAddEdge(NewLoc); 995 996 if (IsConsumedExpr(CLoc) && !IsControlFlowExpr(CLoc.asStmt())) { 997 CLocs.push_back(ContextLocation(CLoc, true)); 998 return; 999 } 1000 } 1001 1002 CLocs.push_back(CLoc); 1003 return; 1004 } 1005 1006 // Context does not contain the location. Flush it. 1007 popLocation(); 1008 } 1009 1010 // If we reach here, there is no enclosing context. Just add the edge. 1011 rawAddEdge(NewLoc); 1012 } 1013 1014 bool EdgeBuilder::IsConsumedExpr(const PathDiagnosticLocation &L) { 1015 if (const Expr *X = dyn_cast_or_null<Expr>(L.asStmt())) 1016 return PDB.getParentMap().isConsumedExpr(X) && !IsControlFlowExpr(X); 1017 1018 return false; 1019 } 1020 1021 void EdgeBuilder::addExtendedContext(const Stmt *S) { 1022 if (!S) 1023 return; 1024 1025 const Stmt *Parent = PDB.getParent(S); 1026 while (Parent) { 1027 if (isa<CompoundStmt>(Parent)) 1028 Parent = PDB.getParent(Parent); 1029 else 1030 break; 1031 } 1032 1033 if (Parent) { 1034 switch (Parent->getStmtClass()) { 1035 case Stmt::DoStmtClass: 1036 case Stmt::ObjCAtSynchronizedStmtClass: 1037 addContext(Parent); 1038 default: 1039 break; 1040 } 1041 } 1042 1043 addContext(S); 1044 } 1045 1046 void EdgeBuilder::addContext(const Stmt *S) { 1047 if (!S) 1048 return; 1049 1050 PathDiagnosticLocation L(S, PDB.getSourceManager(), PDB.LC); 1051 addContext(L); 1052 } 1053 1054 void EdgeBuilder::addContext(const PathDiagnosticLocation &L) { 1055 while (!CLocs.empty()) { 1056 const PathDiagnosticLocation &TopContextLoc = CLocs.back(); 1057 1058 // Is the top location context the same as the one for the new location? 1059 if (TopContextLoc == L) 1060 return; 1061 1062 if (containsLocation(TopContextLoc, L)) { 1063 CLocs.push_back(L); 1064 return; 1065 } 1066 1067 // Context does not contain the location. Flush it. 1068 popLocation(); 1069 } 1070 1071 CLocs.push_back(L); 1072 } 1073 1074 // Cone-of-influence: support the reverse propagation of "interesting" symbols 1075 // and values by tracing interesting calculations backwards through evaluated 1076 // expressions along a path. This is probably overly complicated, but the idea 1077 // is that if an expression computed an "interesting" value, the child 1078 // expressions are are also likely to be "interesting" as well (which then 1079 // propagates to the values they in turn compute). This reverse propagation 1080 // is needed to track interesting correlations across function call boundaries, 1081 // where formal arguments bind to actual arguments, etc. This is also needed 1082 // because the constraint solver sometimes simplifies certain symbolic values 1083 // into constants when appropriate, and this complicates reasoning about 1084 // interesting values. 1085 typedef llvm::DenseSet<const Expr *> InterestingExprs; 1086 1087 static void reversePropagateIntererstingSymbols(BugReport &R, 1088 InterestingExprs &IE, 1089 const ProgramState *State, 1090 const Expr *Ex, 1091 const LocationContext *LCtx) { 1092 SVal V = State->getSVal(Ex, LCtx); 1093 if (!(R.isInteresting(V) || IE.count(Ex))) 1094 return; 1095 1096 switch (Ex->getStmtClass()) { 1097 default: 1098 if (!isa<CastExpr>(Ex)) 1099 break; 1100 // Fall through. 1101 case Stmt::BinaryOperatorClass: 1102 case Stmt::UnaryOperatorClass: { 1103 for (Stmt::const_child_iterator CI = Ex->child_begin(), 1104 CE = Ex->child_end(); 1105 CI != CE; ++CI) { 1106 if (const Expr *child = dyn_cast_or_null<Expr>(*CI)) { 1107 IE.insert(child); 1108 SVal ChildV = State->getSVal(child, LCtx); 1109 R.markInteresting(ChildV); 1110 } 1111 break; 1112 } 1113 } 1114 } 1115 1116 R.markInteresting(V); 1117 } 1118 1119 static void reversePropagateInterestingSymbols(BugReport &R, 1120 InterestingExprs &IE, 1121 const ProgramState *State, 1122 const LocationContext *CalleeCtx, 1123 const LocationContext *CallerCtx) 1124 { 1125 // FIXME: Handle non-CallExpr-based CallEvents. 1126 const StackFrameContext *Callee = CalleeCtx->getCurrentStackFrame(); 1127 const Stmt *CallSite = Callee->getCallSite(); 1128 if (const CallExpr *CE = dyn_cast_or_null<CallExpr>(CallSite)) { 1129 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(CalleeCtx->getDecl())) { 1130 FunctionDecl::param_const_iterator PI = FD->param_begin(), 1131 PE = FD->param_end(); 1132 CallExpr::const_arg_iterator AI = CE->arg_begin(), AE = CE->arg_end(); 1133 for (; AI != AE && PI != PE; ++AI, ++PI) { 1134 if (const Expr *ArgE = *AI) { 1135 if (const ParmVarDecl *PD = *PI) { 1136 Loc LV = State->getLValue(PD, CalleeCtx); 1137 if (R.isInteresting(LV) || R.isInteresting(State->getRawSVal(LV))) 1138 IE.insert(ArgE); 1139 } 1140 } 1141 } 1142 } 1143 } 1144 } 1145 1146 static void GenerateExtensivePathDiagnostic(PathDiagnostic& PD, 1147 PathDiagnosticBuilder &PDB, 1148 const ExplodedNode *N, 1149 ArrayRef<BugReporterVisitor *> visitors) { 1150 EdgeBuilder EB(PD, PDB); 1151 const SourceManager& SM = PDB.getSourceManager(); 1152 StackDiagVector CallStack; 1153 InterestingExprs IE; 1154 1155 const ExplodedNode *NextNode = N->pred_empty() ? NULL : *(N->pred_begin()); 1156 while (NextNode) { 1157 N = NextNode; 1158 NextNode = GetPredecessorNode(N); 1159 ProgramPoint P = N->getLocation(); 1160 1161 do { 1162 if (const PostStmt *PS = dyn_cast<PostStmt>(&P)) { 1163 if (const Expr *Ex = PS->getStmtAs<Expr>()) 1164 reversePropagateIntererstingSymbols(*PDB.getBugReport(), IE, 1165 N->getState().getPtr(), Ex, 1166 N->getLocationContext()); 1167 } 1168 1169 if (const CallExitEnd *CE = dyn_cast<CallExitEnd>(&P)) { 1170 const Stmt *S = CE->getCalleeContext()->getCallSite(); 1171 if (const Expr *Ex = dyn_cast_or_null<Expr>(S)) { 1172 reversePropagateIntererstingSymbols(*PDB.getBugReport(), IE, 1173 N->getState().getPtr(), Ex, 1174 N->getLocationContext()); 1175 } 1176 1177 PathDiagnosticCallPiece *C = 1178 PathDiagnosticCallPiece::construct(N, *CE, SM); 1179 GRBugReporter& BR = PDB.getBugReporter(); 1180 BR.addCallPieceLocationContextPair(C, CE->getCalleeContext()); 1181 1182 EB.addEdge(C->callReturn, true); 1183 EB.flushLocations(); 1184 1185 PD.getActivePath().push_front(C); 1186 PD.pushActivePath(&C->path); 1187 CallStack.push_back(StackDiagPair(C, N)); 1188 break; 1189 } 1190 1191 // Pop the call hierarchy if we are done walking the contents 1192 // of a function call. 1193 if (const CallEnter *CE = dyn_cast<CallEnter>(&P)) { 1194 // Add an edge to the start of the function. 1195 const Decl *D = CE->getCalleeContext()->getDecl(); 1196 PathDiagnosticLocation pos = 1197 PathDiagnosticLocation::createBegin(D, SM); 1198 EB.addEdge(pos); 1199 1200 // Flush all locations, and pop the active path. 1201 bool VisitedEntireCall = PD.isWithinCall(); 1202 EB.flushLocations(); 1203 PD.popActivePath(); 1204 PDB.LC = N->getLocationContext(); 1205 1206 // Either we just added a bunch of stuff to the top-level path, or 1207 // we have a previous CallExitEnd. If the former, it means that the 1208 // path terminated within a function call. We must then take the 1209 // current contents of the active path and place it within 1210 // a new PathDiagnosticCallPiece. 1211 PathDiagnosticCallPiece *C; 1212 if (VisitedEntireCall) { 1213 C = cast<PathDiagnosticCallPiece>(PD.getActivePath().front()); 1214 } else { 1215 const Decl *Caller = CE->getLocationContext()->getDecl(); 1216 C = PathDiagnosticCallPiece::construct(PD.getActivePath(), Caller); 1217 GRBugReporter& BR = PDB.getBugReporter(); 1218 BR.addCallPieceLocationContextPair(C, CE->getCalleeContext()); 1219 } 1220 1221 C->setCallee(*CE, SM); 1222 EB.addContext(C->getLocation()); 1223 1224 if (!CallStack.empty()) { 1225 assert(CallStack.back().first == C); 1226 CallStack.pop_back(); 1227 } 1228 break; 1229 } 1230 1231 // Note that is important that we update the LocationContext 1232 // after looking at CallExits. CallExit basically adds an 1233 // edge in the *caller*, so we don't want to update the LocationContext 1234 // too soon. 1235 PDB.LC = N->getLocationContext(); 1236 1237 // Block edges. 1238 if (const BlockEdge *BE = dyn_cast<BlockEdge>(&P)) { 1239 // Does this represent entering a call? If so, look at propagating 1240 // interesting symbols across call boundaries. 1241 if (NextNode) { 1242 const LocationContext *CallerCtx = NextNode->getLocationContext(); 1243 const LocationContext *CalleeCtx = PDB.LC; 1244 if (CallerCtx != CalleeCtx) { 1245 reversePropagateInterestingSymbols(*PDB.getBugReport(), IE, 1246 N->getState().getPtr(), 1247 CalleeCtx, CallerCtx); 1248 } 1249 } 1250 1251 const CFGBlock &Blk = *BE->getSrc(); 1252 const Stmt *Term = Blk.getTerminator(); 1253 1254 // Are we jumping to the head of a loop? Add a special diagnostic. 1255 if (const Stmt *Loop = BE->getDst()->getLoopTarget()) { 1256 PathDiagnosticLocation L(Loop, SM, PDB.LC); 1257 const CompoundStmt *CS = NULL; 1258 1259 if (!Term) { 1260 if (const ForStmt *FS = dyn_cast<ForStmt>(Loop)) 1261 CS = dyn_cast<CompoundStmt>(FS->getBody()); 1262 else if (const WhileStmt *WS = dyn_cast<WhileStmt>(Loop)) 1263 CS = dyn_cast<CompoundStmt>(WS->getBody()); 1264 } 1265 1266 PathDiagnosticEventPiece *p = 1267 new PathDiagnosticEventPiece(L, 1268 "Looping back to the head of the loop"); 1269 p->setPrunable(true); 1270 1271 EB.addEdge(p->getLocation(), true); 1272 PD.getActivePath().push_front(p); 1273 1274 if (CS) { 1275 PathDiagnosticLocation BL = 1276 PathDiagnosticLocation::createEndBrace(CS, SM); 1277 EB.addEdge(BL); 1278 } 1279 } 1280 1281 if (Term) 1282 EB.addContext(Term); 1283 1284 break; 1285 } 1286 1287 if (const BlockEntrance *BE = dyn_cast<BlockEntrance>(&P)) { 1288 if (const CFGStmt *S = BE->getFirstElement().getAs<CFGStmt>()) { 1289 const Stmt *stmt = S->getStmt(); 1290 if (IsControlFlowExpr(stmt)) { 1291 // Add the proper context for '&&', '||', and '?'. 1292 EB.addContext(stmt); 1293 } 1294 else 1295 EB.addExtendedContext(PDB.getEnclosingStmtLocation(stmt).asStmt()); 1296 } 1297 1298 break; 1299 } 1300 1301 1302 } while (0); 1303 1304 if (!NextNode) 1305 continue; 1306 1307 // Add pieces from custom visitors. 1308 BugReport *R = PDB.getBugReport(); 1309 for (ArrayRef<BugReporterVisitor *>::iterator I = visitors.begin(), 1310 E = visitors.end(); 1311 I != E; ++I) { 1312 if (PathDiagnosticPiece *p = (*I)->VisitNode(N, NextNode, PDB, *R)) { 1313 const PathDiagnosticLocation &Loc = p->getLocation(); 1314 EB.addEdge(Loc, true); 1315 PD.getActivePath().push_front(p); 1316 updateStackPiecesWithMessage(p, CallStack); 1317 1318 if (const Stmt *S = Loc.asStmt()) 1319 EB.addExtendedContext(PDB.getEnclosingStmtLocation(S).asStmt()); 1320 } 1321 } 1322 } 1323 } 1324 1325 //===----------------------------------------------------------------------===// 1326 // Methods for BugType and subclasses. 1327 //===----------------------------------------------------------------------===// 1328 BugType::~BugType() { } 1329 1330 void BugType::FlushReports(BugReporter &BR) {} 1331 1332 void BuiltinBug::anchor() {} 1333 1334 //===----------------------------------------------------------------------===// 1335 // Methods for BugReport and subclasses. 1336 //===----------------------------------------------------------------------===// 1337 1338 void BugReport::NodeResolver::anchor() {} 1339 1340 void BugReport::addVisitor(BugReporterVisitor* visitor) { 1341 if (!visitor) 1342 return; 1343 1344 llvm::FoldingSetNodeID ID; 1345 visitor->Profile(ID); 1346 void *InsertPos; 1347 1348 if (CallbacksSet.FindNodeOrInsertPos(ID, InsertPos)) { 1349 delete visitor; 1350 return; 1351 } 1352 1353 CallbacksSet.InsertNode(visitor, InsertPos); 1354 Callbacks.push_back(visitor); 1355 ++ConfigurationChangeToken; 1356 } 1357 1358 BugReport::~BugReport() { 1359 for (visitor_iterator I = visitor_begin(), E = visitor_end(); I != E; ++I) { 1360 delete *I; 1361 } 1362 while (!interestingSymbols.empty()) { 1363 popInterestingSymbolsAndRegions(); 1364 } 1365 } 1366 1367 const Decl *BugReport::getDeclWithIssue() const { 1368 if (DeclWithIssue) 1369 return DeclWithIssue; 1370 1371 const ExplodedNode *N = getErrorNode(); 1372 if (!N) 1373 return 0; 1374 1375 const LocationContext *LC = N->getLocationContext(); 1376 return LC->getCurrentStackFrame()->getDecl(); 1377 } 1378 1379 void BugReport::Profile(llvm::FoldingSetNodeID& hash) const { 1380 hash.AddPointer(&BT); 1381 hash.AddString(Description); 1382 if (UniqueingLocation.isValid()) { 1383 UniqueingLocation.Profile(hash); 1384 } else if (Location.isValid()) { 1385 Location.Profile(hash); 1386 } else { 1387 assert(ErrorNode); 1388 hash.AddPointer(GetCurrentOrPreviousStmt(ErrorNode)); 1389 } 1390 1391 for (SmallVectorImpl<SourceRange>::const_iterator I = 1392 Ranges.begin(), E = Ranges.end(); I != E; ++I) { 1393 const SourceRange range = *I; 1394 if (!range.isValid()) 1395 continue; 1396 hash.AddInteger(range.getBegin().getRawEncoding()); 1397 hash.AddInteger(range.getEnd().getRawEncoding()); 1398 } 1399 } 1400 1401 void BugReport::markInteresting(SymbolRef sym) { 1402 if (!sym) 1403 return; 1404 1405 // If the symbol wasn't already in our set, note a configuration change. 1406 if (getInterestingSymbols().insert(sym).second) 1407 ++ConfigurationChangeToken; 1408 1409 if (const SymbolMetadata *meta = dyn_cast<SymbolMetadata>(sym)) 1410 getInterestingRegions().insert(meta->getRegion()); 1411 } 1412 1413 void BugReport::markInteresting(const MemRegion *R) { 1414 if (!R) 1415 return; 1416 1417 // If the base region wasn't already in our set, note a configuration change. 1418 R = R->getBaseRegion(); 1419 if (getInterestingRegions().insert(R).second) 1420 ++ConfigurationChangeToken; 1421 1422 if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R)) 1423 getInterestingSymbols().insert(SR->getSymbol()); 1424 } 1425 1426 void BugReport::markInteresting(SVal V) { 1427 markInteresting(V.getAsRegion()); 1428 markInteresting(V.getAsSymbol()); 1429 } 1430 1431 void BugReport::markInteresting(const LocationContext *LC) { 1432 if (!LC) 1433 return; 1434 InterestingLocationContexts.insert(LC); 1435 } 1436 1437 bool BugReport::isInteresting(SVal V) { 1438 return isInteresting(V.getAsRegion()) || isInteresting(V.getAsSymbol()); 1439 } 1440 1441 bool BugReport::isInteresting(SymbolRef sym) { 1442 if (!sym) 1443 return false; 1444 // We don't currently consider metadata symbols to be interesting 1445 // even if we know their region is interesting. Is that correct behavior? 1446 return getInterestingSymbols().count(sym); 1447 } 1448 1449 bool BugReport::isInteresting(const MemRegion *R) { 1450 if (!R) 1451 return false; 1452 R = R->getBaseRegion(); 1453 bool b = getInterestingRegions().count(R); 1454 if (b) 1455 return true; 1456 if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R)) 1457 return getInterestingSymbols().count(SR->getSymbol()); 1458 return false; 1459 } 1460 1461 bool BugReport::isInteresting(const LocationContext *LC) { 1462 if (!LC) 1463 return false; 1464 return InterestingLocationContexts.count(LC); 1465 } 1466 1467 void BugReport::lazyInitializeInterestingSets() { 1468 if (interestingSymbols.empty()) { 1469 interestingSymbols.push_back(new Symbols()); 1470 interestingRegions.push_back(new Regions()); 1471 } 1472 } 1473 1474 BugReport::Symbols &BugReport::getInterestingSymbols() { 1475 lazyInitializeInterestingSets(); 1476 return *interestingSymbols.back(); 1477 } 1478 1479 BugReport::Regions &BugReport::getInterestingRegions() { 1480 lazyInitializeInterestingSets(); 1481 return *interestingRegions.back(); 1482 } 1483 1484 void BugReport::pushInterestingSymbolsAndRegions() { 1485 interestingSymbols.push_back(new Symbols(getInterestingSymbols())); 1486 interestingRegions.push_back(new Regions(getInterestingRegions())); 1487 } 1488 1489 void BugReport::popInterestingSymbolsAndRegions() { 1490 delete interestingSymbols.back(); 1491 interestingSymbols.pop_back(); 1492 delete interestingRegions.back(); 1493 interestingRegions.pop_back(); 1494 } 1495 1496 const Stmt *BugReport::getStmt() const { 1497 if (!ErrorNode) 1498 return 0; 1499 1500 ProgramPoint ProgP = ErrorNode->getLocation(); 1501 const Stmt *S = NULL; 1502 1503 if (BlockEntrance *BE = dyn_cast<BlockEntrance>(&ProgP)) { 1504 CFGBlock &Exit = ProgP.getLocationContext()->getCFG()->getExit(); 1505 if (BE->getBlock() == &Exit) 1506 S = GetPreviousStmt(ErrorNode); 1507 } 1508 if (!S) 1509 S = GetStmt(ProgP); 1510 1511 return S; 1512 } 1513 1514 std::pair<BugReport::ranges_iterator, BugReport::ranges_iterator> 1515 BugReport::getRanges() { 1516 // If no custom ranges, add the range of the statement corresponding to 1517 // the error node. 1518 if (Ranges.empty()) { 1519 if (const Expr *E = dyn_cast_or_null<Expr>(getStmt())) 1520 addRange(E->getSourceRange()); 1521 else 1522 return std::make_pair(ranges_iterator(), ranges_iterator()); 1523 } 1524 1525 // User-specified absence of range info. 1526 if (Ranges.size() == 1 && !Ranges.begin()->isValid()) 1527 return std::make_pair(ranges_iterator(), ranges_iterator()); 1528 1529 return std::make_pair(Ranges.begin(), Ranges.end()); 1530 } 1531 1532 PathDiagnosticLocation BugReport::getLocation(const SourceManager &SM) const { 1533 if (ErrorNode) { 1534 assert(!Location.isValid() && 1535 "Either Location or ErrorNode should be specified but not both."); 1536 1537 if (const Stmt *S = GetCurrentOrPreviousStmt(ErrorNode)) { 1538 const LocationContext *LC = ErrorNode->getLocationContext(); 1539 1540 // For member expressions, return the location of the '.' or '->'. 1541 if (const MemberExpr *ME = dyn_cast<MemberExpr>(S)) 1542 return PathDiagnosticLocation::createMemberLoc(ME, SM); 1543 // For binary operators, return the location of the operator. 1544 if (const BinaryOperator *B = dyn_cast<BinaryOperator>(S)) 1545 return PathDiagnosticLocation::createOperatorLoc(B, SM); 1546 1547 return PathDiagnosticLocation::createBegin(S, SM, LC); 1548 } 1549 } else { 1550 assert(Location.isValid()); 1551 return Location; 1552 } 1553 1554 return PathDiagnosticLocation(); 1555 } 1556 1557 //===----------------------------------------------------------------------===// 1558 // Methods for BugReporter and subclasses. 1559 //===----------------------------------------------------------------------===// 1560 1561 BugReportEquivClass::~BugReportEquivClass() { } 1562 GRBugReporter::~GRBugReporter() { } 1563 BugReporterData::~BugReporterData() {} 1564 1565 ExplodedGraph &GRBugReporter::getGraph() { return Eng.getGraph(); } 1566 1567 ProgramStateManager& 1568 GRBugReporter::getStateManager() { return Eng.getStateManager(); } 1569 1570 BugReporter::~BugReporter() { 1571 FlushReports(); 1572 1573 // Free the bug reports we are tracking. 1574 typedef std::vector<BugReportEquivClass *> ContTy; 1575 for (ContTy::iterator I = EQClassesVector.begin(), E = EQClassesVector.end(); 1576 I != E; ++I) { 1577 delete *I; 1578 } 1579 } 1580 1581 void BugReporter::FlushReports() { 1582 if (BugTypes.isEmpty()) 1583 return; 1584 1585 // First flush the warnings for each BugType. This may end up creating new 1586 // warnings and new BugTypes. 1587 // FIXME: Only NSErrorChecker needs BugType's FlushReports. 1588 // Turn NSErrorChecker into a proper checker and remove this. 1589 SmallVector<const BugType*, 16> bugTypes; 1590 for (BugTypesTy::iterator I=BugTypes.begin(), E=BugTypes.end(); I!=E; ++I) 1591 bugTypes.push_back(*I); 1592 for (SmallVector<const BugType*, 16>::iterator 1593 I = bugTypes.begin(), E = bugTypes.end(); I != E; ++I) 1594 const_cast<BugType*>(*I)->FlushReports(*this); 1595 1596 // We need to flush reports in deterministic order to ensure the order 1597 // of the reports is consistent between runs. 1598 typedef std::vector<BugReportEquivClass *> ContVecTy; 1599 for (ContVecTy::iterator EI=EQClassesVector.begin(), EE=EQClassesVector.end(); 1600 EI != EE; ++EI){ 1601 BugReportEquivClass& EQ = **EI; 1602 FlushReport(EQ); 1603 } 1604 1605 // BugReporter owns and deletes only BugTypes created implicitly through 1606 // EmitBasicReport. 1607 // FIXME: There are leaks from checkers that assume that the BugTypes they 1608 // create will be destroyed by the BugReporter. 1609 for (llvm::StringMap<BugType*>::iterator 1610 I = StrBugTypes.begin(), E = StrBugTypes.end(); I != E; ++I) 1611 delete I->second; 1612 1613 // Remove all references to the BugType objects. 1614 BugTypes = F.getEmptySet(); 1615 } 1616 1617 //===----------------------------------------------------------------------===// 1618 // PathDiagnostics generation. 1619 //===----------------------------------------------------------------------===// 1620 1621 static std::pair<std::pair<ExplodedGraph*, NodeBackMap*>, 1622 std::pair<ExplodedNode*, unsigned> > 1623 MakeReportGraph(const ExplodedGraph* G, 1624 SmallVectorImpl<const ExplodedNode*> &nodes) { 1625 1626 // Create the trimmed graph. It will contain the shortest paths from the 1627 // error nodes to the root. In the new graph we should only have one 1628 // error node unless there are two or more error nodes with the same minimum 1629 // path length. 1630 ExplodedGraph* GTrim; 1631 InterExplodedGraphMap* NMap; 1632 1633 llvm::DenseMap<const void*, const void*> InverseMap; 1634 llvm::tie(GTrim, NMap) = G->Trim(nodes.data(), nodes.data() + nodes.size(), 1635 &InverseMap); 1636 1637 // Create owning pointers for GTrim and NMap just to ensure that they are 1638 // released when this function exists. 1639 OwningPtr<ExplodedGraph> AutoReleaseGTrim(GTrim); 1640 OwningPtr<InterExplodedGraphMap> AutoReleaseNMap(NMap); 1641 1642 // Find the (first) error node in the trimmed graph. We just need to consult 1643 // the node map (NMap) which maps from nodes in the original graph to nodes 1644 // in the new graph. 1645 1646 std::queue<const ExplodedNode*> WS; 1647 typedef llvm::DenseMap<const ExplodedNode*, unsigned> IndexMapTy; 1648 IndexMapTy IndexMap; 1649 1650 for (unsigned nodeIndex = 0 ; nodeIndex < nodes.size(); ++nodeIndex) { 1651 const ExplodedNode *originalNode = nodes[nodeIndex]; 1652 if (const ExplodedNode *N = NMap->getMappedNode(originalNode)) { 1653 WS.push(N); 1654 IndexMap[originalNode] = nodeIndex; 1655 } 1656 } 1657 1658 assert(!WS.empty() && "No error node found in the trimmed graph."); 1659 1660 // Create a new (third!) graph with a single path. This is the graph 1661 // that will be returned to the caller. 1662 ExplodedGraph *GNew = new ExplodedGraph(); 1663 1664 // Sometimes the trimmed graph can contain a cycle. Perform a reverse BFS 1665 // to the root node, and then construct a new graph that contains only 1666 // a single path. 1667 llvm::DenseMap<const void*,unsigned> Visited; 1668 1669 unsigned cnt = 0; 1670 const ExplodedNode *Root = 0; 1671 1672 while (!WS.empty()) { 1673 const ExplodedNode *Node = WS.front(); 1674 WS.pop(); 1675 1676 if (Visited.find(Node) != Visited.end()) 1677 continue; 1678 1679 Visited[Node] = cnt++; 1680 1681 if (Node->pred_empty()) { 1682 Root = Node; 1683 break; 1684 } 1685 1686 for (ExplodedNode::const_pred_iterator I=Node->pred_begin(), 1687 E=Node->pred_end(); I!=E; ++I) 1688 WS.push(*I); 1689 } 1690 1691 assert(Root); 1692 1693 // Now walk from the root down the BFS path, always taking the successor 1694 // with the lowest number. 1695 ExplodedNode *Last = 0, *First = 0; 1696 NodeBackMap *BM = new NodeBackMap(); 1697 unsigned NodeIndex = 0; 1698 1699 for ( const ExplodedNode *N = Root ;;) { 1700 // Lookup the number associated with the current node. 1701 llvm::DenseMap<const void*,unsigned>::iterator I = Visited.find(N); 1702 assert(I != Visited.end()); 1703 1704 // Create the equivalent node in the new graph with the same state 1705 // and location. 1706 ExplodedNode *NewN = GNew->getNode(N->getLocation(), N->getState()); 1707 1708 // Store the mapping to the original node. 1709 llvm::DenseMap<const void*, const void*>::iterator IMitr=InverseMap.find(N); 1710 assert(IMitr != InverseMap.end() && "No mapping to original node."); 1711 (*BM)[NewN] = (const ExplodedNode*) IMitr->second; 1712 1713 // Link up the new node with the previous node. 1714 if (Last) 1715 NewN->addPredecessor(Last, *GNew); 1716 1717 Last = NewN; 1718 1719 // Are we at the final node? 1720 IndexMapTy::iterator IMI = 1721 IndexMap.find((const ExplodedNode*)(IMitr->second)); 1722 if (IMI != IndexMap.end()) { 1723 First = NewN; 1724 NodeIndex = IMI->second; 1725 break; 1726 } 1727 1728 // Find the next successor node. We choose the node that is marked 1729 // with the lowest DFS number. 1730 ExplodedNode::const_succ_iterator SI = N->succ_begin(); 1731 ExplodedNode::const_succ_iterator SE = N->succ_end(); 1732 N = 0; 1733 1734 for (unsigned MinVal = 0; SI != SE; ++SI) { 1735 1736 I = Visited.find(*SI); 1737 1738 if (I == Visited.end()) 1739 continue; 1740 1741 if (!N || I->second < MinVal) { 1742 N = *SI; 1743 MinVal = I->second; 1744 } 1745 } 1746 1747 assert(N); 1748 } 1749 1750 assert(First); 1751 1752 return std::make_pair(std::make_pair(GNew, BM), 1753 std::make_pair(First, NodeIndex)); 1754 } 1755 1756 /// CompactPathDiagnostic - This function postprocesses a PathDiagnostic object 1757 /// and collapses PathDiagosticPieces that are expanded by macros. 1758 static void CompactPathDiagnostic(PathPieces &path, const SourceManager& SM) { 1759 typedef std::vector<std::pair<IntrusiveRefCntPtr<PathDiagnosticMacroPiece>, 1760 SourceLocation> > MacroStackTy; 1761 1762 typedef std::vector<IntrusiveRefCntPtr<PathDiagnosticPiece> > 1763 PiecesTy; 1764 1765 MacroStackTy MacroStack; 1766 PiecesTy Pieces; 1767 1768 for (PathPieces::const_iterator I = path.begin(), E = path.end(); 1769 I!=E; ++I) { 1770 1771 PathDiagnosticPiece *piece = I->getPtr(); 1772 1773 // Recursively compact calls. 1774 if (PathDiagnosticCallPiece *call=dyn_cast<PathDiagnosticCallPiece>(piece)){ 1775 CompactPathDiagnostic(call->path, SM); 1776 } 1777 1778 // Get the location of the PathDiagnosticPiece. 1779 const FullSourceLoc Loc = piece->getLocation().asLocation(); 1780 1781 // Determine the instantiation location, which is the location we group 1782 // related PathDiagnosticPieces. 1783 SourceLocation InstantiationLoc = Loc.isMacroID() ? 1784 SM.getExpansionLoc(Loc) : 1785 SourceLocation(); 1786 1787 if (Loc.isFileID()) { 1788 MacroStack.clear(); 1789 Pieces.push_back(piece); 1790 continue; 1791 } 1792 1793 assert(Loc.isMacroID()); 1794 1795 // Is the PathDiagnosticPiece within the same macro group? 1796 if (!MacroStack.empty() && InstantiationLoc == MacroStack.back().second) { 1797 MacroStack.back().first->subPieces.push_back(piece); 1798 continue; 1799 } 1800 1801 // We aren't in the same group. Are we descending into a new macro 1802 // or are part of an old one? 1803 IntrusiveRefCntPtr<PathDiagnosticMacroPiece> MacroGroup; 1804 1805 SourceLocation ParentInstantiationLoc = InstantiationLoc.isMacroID() ? 1806 SM.getExpansionLoc(Loc) : 1807 SourceLocation(); 1808 1809 // Walk the entire macro stack. 1810 while (!MacroStack.empty()) { 1811 if (InstantiationLoc == MacroStack.back().second) { 1812 MacroGroup = MacroStack.back().first; 1813 break; 1814 } 1815 1816 if (ParentInstantiationLoc == MacroStack.back().second) { 1817 MacroGroup = MacroStack.back().first; 1818 break; 1819 } 1820 1821 MacroStack.pop_back(); 1822 } 1823 1824 if (!MacroGroup || ParentInstantiationLoc == MacroStack.back().second) { 1825 // Create a new macro group and add it to the stack. 1826 PathDiagnosticMacroPiece *NewGroup = 1827 new PathDiagnosticMacroPiece( 1828 PathDiagnosticLocation::createSingleLocation(piece->getLocation())); 1829 1830 if (MacroGroup) 1831 MacroGroup->subPieces.push_back(NewGroup); 1832 else { 1833 assert(InstantiationLoc.isFileID()); 1834 Pieces.push_back(NewGroup); 1835 } 1836 1837 MacroGroup = NewGroup; 1838 MacroStack.push_back(std::make_pair(MacroGroup, InstantiationLoc)); 1839 } 1840 1841 // Finally, add the PathDiagnosticPiece to the group. 1842 MacroGroup->subPieces.push_back(piece); 1843 } 1844 1845 // Now take the pieces and construct a new PathDiagnostic. 1846 path.clear(); 1847 1848 for (PiecesTy::iterator I=Pieces.begin(), E=Pieces.end(); I!=E; ++I) 1849 path.push_back(*I); 1850 } 1851 1852 void GRBugReporter::GeneratePathDiagnostic(PathDiagnostic& PD, 1853 PathDiagnosticConsumer &PC, 1854 ArrayRef<BugReport *> &bugReports) { 1855 1856 assert(!bugReports.empty()); 1857 SmallVector<const ExplodedNode *, 10> errorNodes; 1858 for (ArrayRef<BugReport*>::iterator I = bugReports.begin(), 1859 E = bugReports.end(); I != E; ++I) { 1860 errorNodes.push_back((*I)->getErrorNode()); 1861 } 1862 1863 // Construct a new graph that contains only a single path from the error 1864 // node to a root. 1865 const std::pair<std::pair<ExplodedGraph*, NodeBackMap*>, 1866 std::pair<ExplodedNode*, unsigned> >& 1867 GPair = MakeReportGraph(&getGraph(), errorNodes); 1868 1869 // Find the BugReport with the original location. 1870 assert(GPair.second.second < bugReports.size()); 1871 BugReport *R = bugReports[GPair.second.second]; 1872 assert(R && "No original report found for sliced graph."); 1873 1874 OwningPtr<ExplodedGraph> ReportGraph(GPair.first.first); 1875 OwningPtr<NodeBackMap> BackMap(GPair.first.second); 1876 const ExplodedNode *N = GPair.second.first; 1877 1878 // Start building the path diagnostic... 1879 PathDiagnosticBuilder PDB(*this, R, BackMap.get(), &PC); 1880 1881 // Register additional node visitors. 1882 R->addVisitor(new NilReceiverBRVisitor()); 1883 R->addVisitor(new ConditionBRVisitor()); 1884 1885 BugReport::VisitorList visitors; 1886 unsigned originalReportConfigToken, finalReportConfigToken; 1887 1888 // While generating diagnostics, it's possible the visitors will decide 1889 // new symbols and regions are interesting, or add other visitors based on 1890 // the information they find. If they do, we need to regenerate the path 1891 // based on our new report configuration. 1892 do { 1893 // Get a clean copy of all the visitors. 1894 for (BugReport::visitor_iterator I = R->visitor_begin(), 1895 E = R->visitor_end(); I != E; ++I) 1896 visitors.push_back((*I)->clone()); 1897 1898 // Clear out the active path from any previous work. 1899 PD.resetPath(); 1900 originalReportConfigToken = R->getConfigurationChangeToken(); 1901 1902 // Generate the very last diagnostic piece - the piece is visible before 1903 // the trace is expanded. 1904 PathDiagnosticPiece *LastPiece = 0; 1905 for (BugReport::visitor_iterator I = visitors.begin(), E = visitors.end(); 1906 I != E; ++I) { 1907 if (PathDiagnosticPiece *Piece = (*I)->getEndPath(PDB, N, *R)) { 1908 assert (!LastPiece && 1909 "There can only be one final piece in a diagnostic."); 1910 LastPiece = Piece; 1911 } 1912 } 1913 if (!LastPiece) 1914 LastPiece = BugReporterVisitor::getDefaultEndPath(PDB, N, *R); 1915 if (LastPiece) 1916 PD.setEndOfPath(LastPiece); 1917 else 1918 return; 1919 1920 switch (PDB.getGenerationScheme()) { 1921 case PathDiagnosticConsumer::Extensive: 1922 GenerateExtensivePathDiagnostic(PD, PDB, N, visitors); 1923 break; 1924 case PathDiagnosticConsumer::Minimal: 1925 GenerateMinimalPathDiagnostic(PD, PDB, N, visitors); 1926 break; 1927 case PathDiagnosticConsumer::None: 1928 llvm_unreachable("PathDiagnosticConsumer::None should never appear here"); 1929 } 1930 1931 // Clean up the visitors we used. 1932 llvm::DeleteContainerPointers(visitors); 1933 1934 // Did anything change while generating this path? 1935 finalReportConfigToken = R->getConfigurationChangeToken(); 1936 } while(finalReportConfigToken != originalReportConfigToken); 1937 1938 // Finally, prune the diagnostic path of uninteresting stuff. 1939 if (R->shouldPrunePath()) { 1940 bool hasSomethingInteresting = RemoveUneededCalls(PD.getMutablePieces(), R); 1941 assert(hasSomethingInteresting); 1942 (void) hasSomethingInteresting; 1943 } 1944 } 1945 1946 void BugReporter::Register(BugType *BT) { 1947 BugTypes = F.add(BugTypes, BT); 1948 } 1949 1950 void BugReporter::EmitReport(BugReport* R) { 1951 // Compute the bug report's hash to determine its equivalence class. 1952 llvm::FoldingSetNodeID ID; 1953 R->Profile(ID); 1954 1955 // Lookup the equivance class. If there isn't one, create it. 1956 BugType& BT = R->getBugType(); 1957 Register(&BT); 1958 void *InsertPos; 1959 BugReportEquivClass* EQ = EQClasses.FindNodeOrInsertPos(ID, InsertPos); 1960 1961 if (!EQ) { 1962 EQ = new BugReportEquivClass(R); 1963 EQClasses.InsertNode(EQ, InsertPos); 1964 EQClassesVector.push_back(EQ); 1965 } 1966 else 1967 EQ->AddReport(R); 1968 } 1969 1970 1971 //===----------------------------------------------------------------------===// 1972 // Emitting reports in equivalence classes. 1973 //===----------------------------------------------------------------------===// 1974 1975 namespace { 1976 struct FRIEC_WLItem { 1977 const ExplodedNode *N; 1978 ExplodedNode::const_succ_iterator I, E; 1979 1980 FRIEC_WLItem(const ExplodedNode *n) 1981 : N(n), I(N->succ_begin()), E(N->succ_end()) {} 1982 }; 1983 } 1984 1985 static BugReport * 1986 FindReportInEquivalenceClass(BugReportEquivClass& EQ, 1987 SmallVectorImpl<BugReport*> &bugReports) { 1988 1989 BugReportEquivClass::iterator I = EQ.begin(), E = EQ.end(); 1990 assert(I != E); 1991 BugType& BT = I->getBugType(); 1992 1993 // If we don't need to suppress any of the nodes because they are 1994 // post-dominated by a sink, simply add all the nodes in the equivalence class 1995 // to 'Nodes'. Any of the reports will serve as a "representative" report. 1996 if (!BT.isSuppressOnSink()) { 1997 BugReport *R = I; 1998 for (BugReportEquivClass::iterator I=EQ.begin(), E=EQ.end(); I!=E; ++I) { 1999 const ExplodedNode *N = I->getErrorNode(); 2000 if (N) { 2001 R = I; 2002 bugReports.push_back(R); 2003 } 2004 } 2005 return R; 2006 } 2007 2008 // For bug reports that should be suppressed when all paths are post-dominated 2009 // by a sink node, iterate through the reports in the equivalence class 2010 // until we find one that isn't post-dominated (if one exists). We use a 2011 // DFS traversal of the ExplodedGraph to find a non-sink node. We could write 2012 // this as a recursive function, but we don't want to risk blowing out the 2013 // stack for very long paths. 2014 BugReport *exampleReport = 0; 2015 2016 for (; I != E; ++I) { 2017 const ExplodedNode *errorNode = I->getErrorNode(); 2018 2019 if (!errorNode) 2020 continue; 2021 if (errorNode->isSink()) { 2022 llvm_unreachable( 2023 "BugType::isSuppressSink() should not be 'true' for sink end nodes"); 2024 } 2025 // No successors? By definition this nodes isn't post-dominated by a sink. 2026 if (errorNode->succ_empty()) { 2027 bugReports.push_back(I); 2028 if (!exampleReport) 2029 exampleReport = I; 2030 continue; 2031 } 2032 2033 // At this point we know that 'N' is not a sink and it has at least one 2034 // successor. Use a DFS worklist to find a non-sink end-of-path node. 2035 typedef FRIEC_WLItem WLItem; 2036 typedef SmallVector<WLItem, 10> DFSWorkList; 2037 llvm::DenseMap<const ExplodedNode *, unsigned> Visited; 2038 2039 DFSWorkList WL; 2040 WL.push_back(errorNode); 2041 Visited[errorNode] = 1; 2042 2043 while (!WL.empty()) { 2044 WLItem &WI = WL.back(); 2045 assert(!WI.N->succ_empty()); 2046 2047 for (; WI.I != WI.E; ++WI.I) { 2048 const ExplodedNode *Succ = *WI.I; 2049 // End-of-path node? 2050 if (Succ->succ_empty()) { 2051 // If we found an end-of-path node that is not a sink. 2052 if (!Succ->isSink()) { 2053 bugReports.push_back(I); 2054 if (!exampleReport) 2055 exampleReport = I; 2056 WL.clear(); 2057 break; 2058 } 2059 // Found a sink? Continue on to the next successor. 2060 continue; 2061 } 2062 // Mark the successor as visited. If it hasn't been explored, 2063 // enqueue it to the DFS worklist. 2064 unsigned &mark = Visited[Succ]; 2065 if (!mark) { 2066 mark = 1; 2067 WL.push_back(Succ); 2068 break; 2069 } 2070 } 2071 2072 // The worklist may have been cleared at this point. First 2073 // check if it is empty before checking the last item. 2074 if (!WL.empty() && &WL.back() == &WI) 2075 WL.pop_back(); 2076 } 2077 } 2078 2079 // ExampleReport will be NULL if all the nodes in the equivalence class 2080 // were post-dominated by sinks. 2081 return exampleReport; 2082 } 2083 2084 void BugReporter::FlushReport(BugReportEquivClass& EQ) { 2085 SmallVector<BugReport*, 10> bugReports; 2086 BugReport *exampleReport = FindReportInEquivalenceClass(EQ, bugReports); 2087 if (exampleReport) { 2088 const PathDiagnosticConsumers &C = getPathDiagnosticConsumers(); 2089 for (PathDiagnosticConsumers::const_iterator I=C.begin(), 2090 E=C.end(); I != E; ++I) { 2091 FlushReport(exampleReport, **I, bugReports); 2092 } 2093 } 2094 } 2095 2096 void BugReporter::FlushReport(BugReport *exampleReport, 2097 PathDiagnosticConsumer &PD, 2098 ArrayRef<BugReport*> bugReports) { 2099 2100 // FIXME: Make sure we use the 'R' for the path that was actually used. 2101 // Probably doesn't make a difference in practice. 2102 BugType& BT = exampleReport->getBugType(); 2103 2104 OwningPtr<PathDiagnostic> 2105 D(new PathDiagnostic(exampleReport->getDeclWithIssue(), 2106 exampleReport->getBugType().getName(), 2107 exampleReport->getDescription(), 2108 exampleReport->getShortDescription(/*Fallback=*/false), 2109 BT.getCategory())); 2110 2111 // Generate the full path diagnostic, using the generation scheme 2112 // specified by the PathDiagnosticConsumer. 2113 if (PD.getGenerationScheme() != PathDiagnosticConsumer::None) { 2114 if (!bugReports.empty()) 2115 GeneratePathDiagnostic(*D.get(), PD, bugReports); 2116 } 2117 2118 // If the path is empty, generate a single step path with the location 2119 // of the issue. 2120 if (D->path.empty()) { 2121 PathDiagnosticLocation L = exampleReport->getLocation(getSourceManager()); 2122 PathDiagnosticPiece *piece = 2123 new PathDiagnosticEventPiece(L, exampleReport->getDescription()); 2124 BugReport::ranges_iterator Beg, End; 2125 llvm::tie(Beg, End) = exampleReport->getRanges(); 2126 for ( ; Beg != End; ++Beg) 2127 piece->addRange(*Beg); 2128 D->setEndOfPath(piece); 2129 } 2130 2131 // Get the meta data. 2132 const BugReport::ExtraTextList &Meta = exampleReport->getExtraText(); 2133 for (BugReport::ExtraTextList::const_iterator i = Meta.begin(), 2134 e = Meta.end(); i != e; ++i) { 2135 D->addMeta(*i); 2136 } 2137 2138 PD.HandlePathDiagnostic(D.take()); 2139 } 2140 2141 void BugReporter::EmitBasicReport(const Decl *DeclWithIssue, 2142 StringRef name, 2143 StringRef category, 2144 StringRef str, PathDiagnosticLocation Loc, 2145 SourceRange* RBeg, unsigned NumRanges) { 2146 2147 // 'BT' is owned by BugReporter. 2148 BugType *BT = getBugTypeForName(name, category); 2149 BugReport *R = new BugReport(*BT, str, Loc); 2150 R->setDeclWithIssue(DeclWithIssue); 2151 for ( ; NumRanges > 0 ; --NumRanges, ++RBeg) R->addRange(*RBeg); 2152 EmitReport(R); 2153 } 2154 2155 BugType *BugReporter::getBugTypeForName(StringRef name, 2156 StringRef category) { 2157 SmallString<136> fullDesc; 2158 llvm::raw_svector_ostream(fullDesc) << name << ":" << category; 2159 llvm::StringMapEntry<BugType *> & 2160 entry = StrBugTypes.GetOrCreateValue(fullDesc); 2161 BugType *BT = entry.getValue(); 2162 if (!BT) { 2163 BT = new BugType(name, category); 2164 entry.setValue(BT); 2165 } 2166 return BT; 2167 } 2168