clang  14.0.0git
BugReporter.cpp
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1 //===- BugReporter.cpp - Generate PathDiagnostics for bugs ----------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file defines BugReporter, a utility class for generating
10 // PathDiagnostics.
11 //
12 //===----------------------------------------------------------------------===//
13 
15 #include "clang/AST/Decl.h"
16 #include "clang/AST/DeclBase.h"
17 #include "clang/AST/DeclObjC.h"
18 #include "clang/AST/Expr.h"
19 #include "clang/AST/ExprCXX.h"
20 #include "clang/AST/ParentMap.h"
21 #include "clang/AST/Stmt.h"
22 #include "clang/AST/StmtCXX.h"
23 #include "clang/AST/StmtObjC.h"
25 #include "clang/Analysis/CFG.h"
29 #include "clang/Basic/LLVM.h"
45 #include "llvm/ADT/ArrayRef.h"
46 #include "llvm/ADT/DenseMap.h"
47 #include "llvm/ADT/DenseSet.h"
48 #include "llvm/ADT/FoldingSet.h"
49 #include "llvm/ADT/None.h"
50 #include "llvm/ADT/Optional.h"
51 #include "llvm/ADT/STLExtras.h"
52 #include "llvm/ADT/SmallPtrSet.h"
53 #include "llvm/ADT/SmallString.h"
54 #include "llvm/ADT/SmallVector.h"
55 #include "llvm/ADT/Statistic.h"
56 #include "llvm/ADT/StringExtras.h"
57 #include "llvm/ADT/StringRef.h"
58 #include "llvm/ADT/iterator_range.h"
59 #include "llvm/Support/Casting.h"
60 #include "llvm/Support/Compiler.h"
61 #include "llvm/Support/ErrorHandling.h"
62 #include "llvm/Support/MemoryBuffer.h"
63 #include "llvm/Support/raw_ostream.h"
64 #include <algorithm>
65 #include <cassert>
66 #include <cstddef>
67 #include <iterator>
68 #include <memory>
69 #include <queue>
70 #include <string>
71 #include <tuple>
72 #include <utility>
73 #include <vector>
74 
75 using namespace clang;
76 using namespace ento;
77 using namespace llvm;
78 
79 #define DEBUG_TYPE "BugReporter"
80 
81 STATISTIC(MaxBugClassSize,
82  "The maximum number of bug reports in the same equivalence class");
83 STATISTIC(MaxValidBugClassSize,
84  "The maximum number of bug reports in the same equivalence class "
85  "where at least one report is valid (not suppressed)");
86 
88 
89 void BugReporterContext::anchor() {}
90 
91 //===----------------------------------------------------------------------===//
92 // PathDiagnosticBuilder and its associated routines and helper objects.
93 //===----------------------------------------------------------------------===//
94 
95 namespace {
96 
97 /// A (CallPiece, node assiciated with its CallEnter) pair.
98 using CallWithEntry =
99  std::pair<PathDiagnosticCallPiece *, const ExplodedNode *>;
100 using CallWithEntryStack = SmallVector<CallWithEntry, 6>;
101 
102 /// Map from each node to the diagnostic pieces visitors emit for them.
103 using VisitorsDiagnosticsTy =
104  llvm::DenseMap<const ExplodedNode *, std::vector<PathDiagnosticPieceRef>>;
105 
106 /// A map from PathDiagnosticPiece to the LocationContext of the inlined
107 /// function call it represents.
108 using LocationContextMap =
109  llvm::DenseMap<const PathPieces *, const LocationContext *>;
110 
111 /// A helper class that contains everything needed to construct a
112 /// PathDiagnostic object. It does no much more then providing convenient
113 /// getters and some well placed asserts for extra security.
114 class PathDiagnosticConstruct {
115  /// The consumer we're constructing the bug report for.
116  const PathDiagnosticConsumer *Consumer;
117  /// Our current position in the bug path, which is owned by
118  /// PathDiagnosticBuilder.
119  const ExplodedNode *CurrentNode;
120  /// A mapping from parts of the bug path (for example, a function call, which
121  /// would span backwards from a CallExit to a CallEnter with the nodes in
122  /// between them) with the location contexts it is associated with.
123  LocationContextMap LCM;
124  const SourceManager &SM;
125 
126 public:
127  /// We keep stack of calls to functions as we're ascending the bug path.
128  /// TODO: PathDiagnostic has a stack doing the same thing, shouldn't we use
129  /// that instead?
130  CallWithEntryStack CallStack;
131  /// The bug report we're constructing. For ease of use, this field is kept
132  /// public, though some "shortcut" getters are provided for commonly used
133  /// methods of PathDiagnostic.
134  std::unique_ptr<PathDiagnostic> PD;
135 
136 public:
137  PathDiagnosticConstruct(const PathDiagnosticConsumer *PDC,
138  const ExplodedNode *ErrorNode,
139  const PathSensitiveBugReport *R);
140 
141  /// \returns the location context associated with the current position in the
142  /// bug path.
143  const LocationContext *getCurrLocationContext() const {
144  assert(CurrentNode && "Already reached the root!");
145  return CurrentNode->getLocationContext();
146  }
147 
148  /// Same as getCurrLocationContext (they should always return the same
149  /// location context), but works after reaching the root of the bug path as
150  /// well.
151  const LocationContext *getLocationContextForActivePath() const {
152  return LCM.find(&PD->getActivePath())->getSecond();
153  }
154 
155  const ExplodedNode *getCurrentNode() const { return CurrentNode; }
156 
157  /// Steps the current node to its predecessor.
158  /// \returns whether we reached the root of the bug path.
159  bool ascendToPrevNode() {
160  CurrentNode = CurrentNode->getFirstPred();
161  return static_cast<bool>(CurrentNode);
162  }
163 
164  const ParentMap &getParentMap() const {
165  return getCurrLocationContext()->getParentMap();
166  }
167 
168  const SourceManager &getSourceManager() const { return SM; }
169 
170  const Stmt *getParent(const Stmt *S) const {
171  return getParentMap().getParent(S);
172  }
173 
174  void updateLocCtxMap(const PathPieces *Path, const LocationContext *LC) {
175  assert(Path && LC);
176  LCM[Path] = LC;
177  }
178 
179  const LocationContext *getLocationContextFor(const PathPieces *Path) const {
180  assert(LCM.count(Path) &&
181  "Failed to find the context associated with these pieces!");
182  return LCM.find(Path)->getSecond();
183  }
184 
185  bool isInLocCtxMap(const PathPieces *Path) const { return LCM.count(Path); }
186 
187  PathPieces &getActivePath() { return PD->getActivePath(); }
188  PathPieces &getMutablePieces() { return PD->getMutablePieces(); }
189 
190  bool shouldAddPathEdges() const { return Consumer->shouldAddPathEdges(); }
191  bool shouldAddControlNotes() const {
192  return Consumer->shouldAddControlNotes();
193  }
194  bool shouldGenerateDiagnostics() const {
195  return Consumer->shouldGenerateDiagnostics();
196  }
197  bool supportsLogicalOpControlFlow() const {
198  return Consumer->supportsLogicalOpControlFlow();
199  }
200 };
201 
202 /// Contains every contextual information needed for constructing a
203 /// PathDiagnostic object for a given bug report. This class and its fields are
204 /// immutable, and passes a BugReportConstruct object around during the
205 /// construction.
206 class PathDiagnosticBuilder : public BugReporterContext {
207  /// A linear path from the error node to the root.
208  std::unique_ptr<const ExplodedGraph> BugPath;
209  /// The bug report we're describing. Visitors create their diagnostics with
210  /// them being the last entities being able to modify it (for example,
211  /// changing interestingness here would cause inconsistencies as to how this
212  /// file and visitors construct diagnostics), hence its const.
213  const PathSensitiveBugReport *R;
214  /// The leaf of the bug path. This isn't the same as the bug reports error
215  /// node, which refers to the *original* graph, not the bug path.
216  const ExplodedNode *const ErrorNode;
217  /// The diagnostic pieces visitors emitted, which is expected to be collected
218  /// by the time this builder is constructed.
219  std::unique_ptr<const VisitorsDiagnosticsTy> VisitorsDiagnostics;
220 
221 public:
222  /// Find a non-invalidated report for a given equivalence class, and returns
223  /// a PathDiagnosticBuilder able to construct bug reports for different
224  /// consumers. Returns None if no valid report is found.
226  findValidReport(ArrayRef<PathSensitiveBugReport *> &bugReports,
227  PathSensitiveBugReporter &Reporter);
228 
229  PathDiagnosticBuilder(
230  BugReporterContext BRC, std::unique_ptr<ExplodedGraph> BugPath,
231  PathSensitiveBugReport *r, const ExplodedNode *ErrorNode,
232  std::unique_ptr<VisitorsDiagnosticsTy> VisitorsDiagnostics);
233 
234  /// This function is responsible for generating diagnostic pieces that are
235  /// *not* provided by bug report visitors.
236  /// These diagnostics may differ depending on the consumer's settings,
237  /// and are therefore constructed separately for each consumer.
238  ///
239  /// There are two path diagnostics generation modes: with adding edges (used
240  /// for plists) and without (used for HTML and text). When edges are added,
241  /// the path is modified to insert artificially generated edges.
242  /// Otherwise, more detailed diagnostics is emitted for block edges,
243  /// explaining the transitions in words.
244  std::unique_ptr<PathDiagnostic>
245  generate(const PathDiagnosticConsumer *PDC) const;
246 
247 private:
248  void updateStackPiecesWithMessage(PathDiagnosticPieceRef P,
249  const CallWithEntryStack &CallStack) const;
250  void generatePathDiagnosticsForNode(PathDiagnosticConstruct &C,
251  PathDiagnosticLocation &PrevLoc) const;
252 
253  void generateMinimalDiagForBlockEdge(PathDiagnosticConstruct &C,
254  BlockEdge BE) const;
255 
257  generateDiagForGotoOP(const PathDiagnosticConstruct &C, const Stmt *S,
258  PathDiagnosticLocation &Start) const;
259 
261  generateDiagForSwitchOP(const PathDiagnosticConstruct &C, const CFGBlock *Dst,
262  PathDiagnosticLocation &Start) const;
263 
265  generateDiagForBinaryOP(const PathDiagnosticConstruct &C, const Stmt *T,
266  const CFGBlock *Src, const CFGBlock *DstC) const;
267 
268  PathDiagnosticLocation
269  ExecutionContinues(const PathDiagnosticConstruct &C) const;
270 
271  PathDiagnosticLocation
272  ExecutionContinues(llvm::raw_string_ostream &os,
273  const PathDiagnosticConstruct &C) const;
274 
275  const PathSensitiveBugReport *getBugReport() const { return R; }
276 };
277 
278 } // namespace
279 
280 //===----------------------------------------------------------------------===//
281 // Base implementation of stack hint generators.
282 //===----------------------------------------------------------------------===//
283 
285 
287  if (!N)
288  return getMessageForSymbolNotFound();
289 
290  ProgramPoint P = N->getLocation();
291  CallExitEnd CExit = P.castAs<CallExitEnd>();
292 
293  // FIXME: Use CallEvent to abstract this over all calls.
294  const Stmt *CallSite = CExit.getCalleeContext()->getCallSite();
295  const auto *CE = dyn_cast_or_null<CallExpr>(CallSite);
296  if (!CE)
297  return {};
298 
299  // Check if one of the parameters are set to the interesting symbol.
300  unsigned ArgIndex = 0;
301  for (CallExpr::const_arg_iterator I = CE->arg_begin(),
302  E = CE->arg_end(); I != E; ++I, ++ArgIndex){
303  SVal SV = N->getSVal(*I);
304 
305  // Check if the variable corresponding to the symbol is passed by value.
306  SymbolRef AS = SV.getAsLocSymbol();
307  if (AS == Sym) {
308  return getMessageForArg(*I, ArgIndex);
309  }
310 
311  // Check if the parameter is a pointer to the symbol.
313  // Do not attempt to dereference void*.
314  if ((*I)->getType()->isVoidPointerType())
315  continue;
316  SVal PSV = N->getState()->getSVal(Reg->getRegion());
317  SymbolRef AS = PSV.getAsLocSymbol();
318  if (AS == Sym) {
319  return getMessageForArg(*I, ArgIndex);
320  }
321  }
322  }
323 
324  // Check if we are returning the interesting symbol.
325  SVal SV = N->getSVal(CE);
326  SymbolRef RetSym = SV.getAsLocSymbol();
327  if (RetSym == Sym) {
328  return getMessageForReturn(CE);
329  }
330 
331  return getMessageForSymbolNotFound();
332 }
333 
335  unsigned ArgIndex) {
336  // Printed parameters start at 1, not 0.
337  ++ArgIndex;
338 
339  return (llvm::Twine(Msg) + " via " + std::to_string(ArgIndex) +
340  llvm::getOrdinalSuffix(ArgIndex) + " parameter").str();
341 }
342 
343 //===----------------------------------------------------------------------===//
344 // Diagnostic cleanup.
345 //===----------------------------------------------------------------------===//
346 
348 eventsDescribeSameCondition(PathDiagnosticEventPiece *X,
349  PathDiagnosticEventPiece *Y) {
350  // Prefer diagnostics that come from ConditionBRVisitor over
351  // those that came from TrackConstraintBRVisitor,
352  // unless the one from ConditionBRVisitor is
353  // its generic fallback diagnostic.
354  const void *tagPreferred = ConditionBRVisitor::getTag();
355  const void *tagLesser = TrackConstraintBRVisitor::getTag();
356 
357  if (X->getLocation() != Y->getLocation())
358  return nullptr;
359 
360  if (X->getTag() == tagPreferred && Y->getTag() == tagLesser)
362 
363  if (Y->getTag() == tagPreferred && X->getTag() == tagLesser)
365 
366  return nullptr;
367 }
368 
369 /// An optimization pass over PathPieces that removes redundant diagnostics
370 /// generated by both ConditionBRVisitor and TrackConstraintBRVisitor. Both
371 /// BugReporterVisitors use different methods to generate diagnostics, with
372 /// one capable of emitting diagnostics in some cases but not in others. This
373 /// can lead to redundant diagnostic pieces at the same point in a path.
374 static void removeRedundantMsgs(PathPieces &path) {
375  unsigned N = path.size();
376  if (N < 2)
377  return;
378  // NOTE: this loop intentionally is not using an iterator. Instead, we
379  // are streaming the path and modifying it in place. This is done by
380  // grabbing the front, processing it, and if we decide to keep it append
381  // it to the end of the path. The entire path is processed in this way.
382  for (unsigned i = 0; i < N; ++i) {
383  auto piece = std::move(path.front());
384  path.pop_front();
385 
386  switch (piece->getKind()) {
388  removeRedundantMsgs(cast<PathDiagnosticCallPiece>(*piece).path);
389  break;
391  removeRedundantMsgs(cast<PathDiagnosticMacroPiece>(*piece).subPieces);
392  break;
394  if (i == N-1)
395  break;
396 
397  if (auto *nextEvent =
398  dyn_cast<PathDiagnosticEventPiece>(path.front().get())) {
399  auto *event = cast<PathDiagnosticEventPiece>(piece.get());
400  // Check to see if we should keep one of the two pieces. If we
401  // come up with a preference, record which piece to keep, and consume
402  // another piece from the path.
403  if (auto *pieceToKeep =
404  eventsDescribeSameCondition(event, nextEvent)) {
405  piece = std::move(pieceToKeep == event ? piece : path.front());
406  path.pop_front();
407  ++i;
408  }
409  }
410  break;
411  }
415  break;
416  }
417  path.push_back(std::move(piece));
418  }
419 }
420 
421 /// Recursively scan through a path and prune out calls and macros pieces
422 /// that aren't needed. Return true if afterwards the path contains
423 /// "interesting stuff" which means it shouldn't be pruned from the parent path.
424 static bool removeUnneededCalls(const PathDiagnosticConstruct &C,
425  PathPieces &pieces,
426  const PathSensitiveBugReport *R,
427  bool IsInteresting = false) {
428  bool containsSomethingInteresting = IsInteresting;
429  const unsigned N = pieces.size();
430 
431  for (unsigned i = 0 ; i < N ; ++i) {
432  // Remove the front piece from the path. If it is still something we
433  // want to keep once we are done, we will push it back on the end.
434  auto piece = std::move(pieces.front());
435  pieces.pop_front();
436 
437  switch (piece->getKind()) {
439  auto &call = cast<PathDiagnosticCallPiece>(*piece);
440  // Check if the location context is interesting.
441  if (!removeUnneededCalls(
442  C, call.path, R,
443  R->isInteresting(C.getLocationContextFor(&call.path))))
444  continue;
445 
446  containsSomethingInteresting = true;
447  break;
448  }
450  auto &macro = cast<PathDiagnosticMacroPiece>(*piece);
451  if (!removeUnneededCalls(C, macro.subPieces, R, IsInteresting))
452  continue;
453  containsSomethingInteresting = true;
454  break;
455  }
457  auto &event = cast<PathDiagnosticEventPiece>(*piece);
458 
459  // We never throw away an event, but we do throw it away wholesale
460  // as part of a path if we throw the entire path away.
461  containsSomethingInteresting |= !event.isPrunable();
462  break;
463  }
467  break;
468  }
469 
470  pieces.push_back(std::move(piece));
471  }
472 
473  return containsSomethingInteresting;
474 }
475 
476 /// Same logic as above to remove extra pieces.
477 static void removePopUpNotes(PathPieces &Path) {
478  for (unsigned int i = 0; i < Path.size(); ++i) {
479  auto Piece = std::move(Path.front());
480  Path.pop_front();
481  if (!isa<PathDiagnosticPopUpPiece>(*Piece))
482  Path.push_back(std::move(Piece));
483  }
484 }
485 
486 /// Returns true if the given decl has been implicitly given a body, either by
487 /// the analyzer or by the compiler proper.
488 static bool hasImplicitBody(const Decl *D) {
489  assert(D);
490  return D->isImplicit() || !D->hasBody();
491 }
492 
493 /// Recursively scan through a path and make sure that all call pieces have
494 /// valid locations.
495 static void
496 adjustCallLocations(PathPieces &Pieces,
497  PathDiagnosticLocation *LastCallLocation = nullptr) {
498  for (const auto &I : Pieces) {
499  auto *Call = dyn_cast<PathDiagnosticCallPiece>(I.get());
500 
501  if (!Call)
502  continue;
503 
504  if (LastCallLocation) {
505  bool CallerIsImplicit = hasImplicitBody(Call->getCaller());
506  if (CallerIsImplicit || !Call->callEnter.asLocation().isValid())
507  Call->callEnter = *LastCallLocation;
508  if (CallerIsImplicit || !Call->callReturn.asLocation().isValid())
509  Call->callReturn = *LastCallLocation;
510  }
511 
512  // Recursively clean out the subclass. Keep this call around if
513  // it contains any informative diagnostics.
514  PathDiagnosticLocation *ThisCallLocation;
515  if (Call->callEnterWithin.asLocation().isValid() &&
516  !hasImplicitBody(Call->getCallee()))
517  ThisCallLocation = &Call->callEnterWithin;
518  else
519  ThisCallLocation = &Call->callEnter;
520 
521  assert(ThisCallLocation && "Outermost call has an invalid location");
522  adjustCallLocations(Call->path, ThisCallLocation);
523  }
524 }
525 
526 /// Remove edges in and out of C++ default initializer expressions. These are
527 /// for fields that have in-class initializers, as opposed to being initialized
528 /// explicitly in a constructor or braced list.
529 static void removeEdgesToDefaultInitializers(PathPieces &Pieces) {
530  for (PathPieces::iterator I = Pieces.begin(), E = Pieces.end(); I != E;) {
531  if (auto *C = dyn_cast<PathDiagnosticCallPiece>(I->get()))
533 
534  if (auto *M = dyn_cast<PathDiagnosticMacroPiece>(I->get()))
535  removeEdgesToDefaultInitializers(M->subPieces);
536 
537  if (auto *CF = dyn_cast<PathDiagnosticControlFlowPiece>(I->get())) {
538  const Stmt *Start = CF->getStartLocation().asStmt();
539  const Stmt *End = CF->getEndLocation().asStmt();
540  if (isa_and_nonnull<CXXDefaultInitExpr>(Start)) {
541  I = Pieces.erase(I);
542  continue;
543  } else if (isa_and_nonnull<CXXDefaultInitExpr>(End)) {
544  PathPieces::iterator Next = std::next(I);
545  if (Next != E) {
546  if (auto *NextCF =
547  dyn_cast<PathDiagnosticControlFlowPiece>(Next->get())) {
548  NextCF->setStartLocation(CF->getStartLocation());
549  }
550  }
551  I = Pieces.erase(I);
552  continue;
553  }
554  }
555 
556  I++;
557  }
558 }
559 
560 /// Remove all pieces with invalid locations as these cannot be serialized.
561 /// We might have pieces with invalid locations as a result of inlining Body
562 /// Farm generated functions.
563 static void removePiecesWithInvalidLocations(PathPieces &Pieces) {
564  for (PathPieces::iterator I = Pieces.begin(), E = Pieces.end(); I != E;) {
565  if (auto *C = dyn_cast<PathDiagnosticCallPiece>(I->get()))
567 
568  if (auto *M = dyn_cast<PathDiagnosticMacroPiece>(I->get()))
569  removePiecesWithInvalidLocations(M->subPieces);
570 
571  if (!(*I)->getLocation().isValid() ||
572  !(*I)->getLocation().asLocation().isValid()) {
573  I = Pieces.erase(I);
574  continue;
575  }
576  I++;
577  }
578 }
579 
580 PathDiagnosticLocation PathDiagnosticBuilder::ExecutionContinues(
581  const PathDiagnosticConstruct &C) const {
582  if (const Stmt *S = C.getCurrentNode()->getNextStmtForDiagnostics())
583  return PathDiagnosticLocation(S, getSourceManager(),
584  C.getCurrLocationContext());
585 
586  return PathDiagnosticLocation::createDeclEnd(C.getCurrLocationContext(),
587  getSourceManager());
588 }
589 
590 PathDiagnosticLocation PathDiagnosticBuilder::ExecutionContinues(
591  llvm::raw_string_ostream &os, const PathDiagnosticConstruct &C) const {
592  // Slow, but probably doesn't matter.
593  if (os.str().empty())
594  os << ' ';
595 
596  const PathDiagnosticLocation &Loc = ExecutionContinues(C);
597 
598  if (Loc.asStmt())
599  os << "Execution continues on line "
600  << getSourceManager().getExpansionLineNumber(Loc.asLocation())
601  << '.';
602  else {
603  os << "Execution jumps to the end of the ";
604  const Decl *D = C.getCurrLocationContext()->getDecl();
605  if (isa<ObjCMethodDecl>(D))
606  os << "method";
607  else if (isa<FunctionDecl>(D))
608  os << "function";
609  else {
610  assert(isa<BlockDecl>(D));
611  os << "anonymous block";
612  }
613  os << '.';
614  }
615 
616  return Loc;
617 }
618 
619 static const Stmt *getEnclosingParent(const Stmt *S, const ParentMap &PM) {
620  if (isa<Expr>(S) && PM.isConsumedExpr(cast<Expr>(S)))
621  return PM.getParentIgnoreParens(S);
622 
623  const Stmt *Parent = PM.getParentIgnoreParens(S);
624  if (!Parent)
625  return nullptr;
626 
627  switch (Parent->getStmtClass()) {
628  case Stmt::ForStmtClass:
629  case Stmt::DoStmtClass:
630  case Stmt::WhileStmtClass:
631  case Stmt::ObjCForCollectionStmtClass:
632  case Stmt::CXXForRangeStmtClass:
633  return Parent;
634  default:
635  break;
636  }
637 
638  return nullptr;
639 }
640 
641 static PathDiagnosticLocation
643  bool allowNestedContexts = false) {
644  if (!S)
645  return {};
646 
647  const SourceManager &SMgr = LC->getDecl()->getASTContext().getSourceManager();
648 
649  while (const Stmt *Parent = getEnclosingParent(S, LC->getParentMap())) {
650  switch (Parent->getStmtClass()) {
651  case Stmt::BinaryOperatorClass: {
652  const auto *B = cast<BinaryOperator>(Parent);
653  if (B->isLogicalOp())
654  return PathDiagnosticLocation(allowNestedContexts ? B : S, SMgr, LC);
655  break;
656  }
657  case Stmt::CompoundStmtClass:
658  case Stmt::StmtExprClass:
659  return PathDiagnosticLocation(S, SMgr, LC);
660  case Stmt::ChooseExprClass:
661  // Similar to '?' if we are referring to condition, just have the edge
662  // point to the entire choose expression.
663  if (allowNestedContexts || cast<ChooseExpr>(Parent)->getCond() == S)
664  return PathDiagnosticLocation(Parent, SMgr, LC);
665  else
666  return PathDiagnosticLocation(S, SMgr, LC);
667  case Stmt::BinaryConditionalOperatorClass:
668  case Stmt::ConditionalOperatorClass:
669  // For '?', if we are referring to condition, just have the edge point
670  // to the entire '?' expression.
671  if (allowNestedContexts ||
672  cast<AbstractConditionalOperator>(Parent)->getCond() == S)
673  return PathDiagnosticLocation(Parent, SMgr, LC);
674  else
675  return PathDiagnosticLocation(S, SMgr, LC);
676  case Stmt::CXXForRangeStmtClass:
677  if (cast<CXXForRangeStmt>(Parent)->getBody() == S)
678  return PathDiagnosticLocation(S, SMgr, LC);
679  break;
680  case Stmt::DoStmtClass:
681  return PathDiagnosticLocation(S, SMgr, LC);
682  case Stmt::ForStmtClass:
683  if (cast<ForStmt>(Parent)->getBody() == S)
684  return PathDiagnosticLocation(S, SMgr, LC);
685  break;
686  case Stmt::IfStmtClass:
687  if (cast<IfStmt>(Parent)->getCond() != S)
688  return PathDiagnosticLocation(S, SMgr, LC);
689  break;
690  case Stmt::ObjCForCollectionStmtClass:
691  if (cast<ObjCForCollectionStmt>(Parent)->getBody() == S)
692  return PathDiagnosticLocation(S, SMgr, LC);
693  break;
694  case Stmt::WhileStmtClass:
695  if (cast<WhileStmt>(Parent)->getCond() != S)
696  return PathDiagnosticLocation(S, SMgr, LC);
697  break;
698  default:
699  break;
700  }
701 
702  S = Parent;
703  }
704 
705  assert(S && "Cannot have null Stmt for PathDiagnosticLocation");
706 
707  return PathDiagnosticLocation(S, SMgr, LC);
708 }
709 
710 //===----------------------------------------------------------------------===//
711 // "Minimal" path diagnostic generation algorithm.
712 //===----------------------------------------------------------------------===//
713 
714 /// If the piece contains a special message, add it to all the call pieces on
715 /// the active stack. For example, my_malloc allocated memory, so MallocChecker
716 /// will construct an event at the call to malloc(), and add a stack hint that
717 /// an allocated memory was returned. We'll use this hint to construct a message
718 /// when returning from the call to my_malloc
719 ///
720 /// void *my_malloc() { return malloc(sizeof(int)); }
721 /// void fishy() {
722 /// void *ptr = my_malloc(); // returned allocated memory
723 /// } // leak
724 void PathDiagnosticBuilder::updateStackPiecesWithMessage(
725  PathDiagnosticPieceRef P, const CallWithEntryStack &CallStack) const {
726  if (R->hasCallStackHint(P))
727  for (const auto &I : CallStack) {
728  PathDiagnosticCallPiece *CP = I.first;
729  const ExplodedNode *N = I.second;
730  std::string stackMsg = R->getCallStackMessage(P, N);
731 
732  // The last message on the path to final bug is the most important
733  // one. Since we traverse the path backwards, do not add the message
734  // if one has been previously added.
735  if (!CP->hasCallStackMessage())
736  CP->setCallStackMessage(stackMsg);
737  }
738 }
739 
740 static void CompactMacroExpandedPieces(PathPieces &path,
741  const SourceManager& SM);
742 
743 PathDiagnosticPieceRef PathDiagnosticBuilder::generateDiagForSwitchOP(
744  const PathDiagnosticConstruct &C, const CFGBlock *Dst,
745  PathDiagnosticLocation &Start) const {
746 
747  const SourceManager &SM = getSourceManager();
748  // Figure out what case arm we took.
749  std::string sbuf;
750  llvm::raw_string_ostream os(sbuf);
751  PathDiagnosticLocation End;
752 
753  if (const Stmt *S = Dst->getLabel()) {
754  End = PathDiagnosticLocation(S, SM, C.getCurrLocationContext());
755 
756  switch (S->getStmtClass()) {
757  default:
758  os << "No cases match in the switch statement. "
759  "Control jumps to line "
760  << End.asLocation().getExpansionLineNumber();
761  break;
762  case Stmt::DefaultStmtClass:
763  os << "Control jumps to the 'default' case at line "
764  << End.asLocation().getExpansionLineNumber();
765  break;
766 
767  case Stmt::CaseStmtClass: {
768  os << "Control jumps to 'case ";
769  const auto *Case = cast<CaseStmt>(S);
770  const Expr *LHS = Case->getLHS()->IgnoreParenCasts();
771 
772  // Determine if it is an enum.
773  bool GetRawInt = true;
774 
775  if (const auto *DR = dyn_cast<DeclRefExpr>(LHS)) {
776  // FIXME: Maybe this should be an assertion. Are there cases
777  // were it is not an EnumConstantDecl?
778  const auto *D = dyn_cast<EnumConstantDecl>(DR->getDecl());
779 
780  if (D) {
781  GetRawInt = false;
782  os << *D;
783  }
784  }
785 
786  if (GetRawInt)
787  os << LHS->EvaluateKnownConstInt(getASTContext());
788 
789  os << ":' at line " << End.asLocation().getExpansionLineNumber();
790  break;
791  }
792  }
793  } else {
794  os << "'Default' branch taken. ";
795  End = ExecutionContinues(os, C);
796  }
797  return std::make_shared<PathDiagnosticControlFlowPiece>(Start, End,
798  os.str());
799 }
800 
801 PathDiagnosticPieceRef PathDiagnosticBuilder::generateDiagForGotoOP(
802  const PathDiagnosticConstruct &C, const Stmt *S,
803  PathDiagnosticLocation &Start) const {
804  std::string sbuf;
805  llvm::raw_string_ostream os(sbuf);
806  const PathDiagnosticLocation &End =
807  getEnclosingStmtLocation(S, C.getCurrLocationContext());
808  os << "Control jumps to line " << End.asLocation().getExpansionLineNumber();
809  return std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, os.str());
810 }
811 
812 PathDiagnosticPieceRef PathDiagnosticBuilder::generateDiagForBinaryOP(
813  const PathDiagnosticConstruct &C, const Stmt *T, const CFGBlock *Src,
814  const CFGBlock *Dst) const {
815 
816  const SourceManager &SM = getSourceManager();
817 
818  const auto *B = cast<BinaryOperator>(T);
819  std::string sbuf;
820  llvm::raw_string_ostream os(sbuf);
821  os << "Left side of '";
822  PathDiagnosticLocation Start, End;
823 
824  if (B->getOpcode() == BO_LAnd) {
825  os << "&&"
826  << "' is ";
827 
828  if (*(Src->succ_begin() + 1) == Dst) {
829  os << "false";
830  End = PathDiagnosticLocation(B->getLHS(), SM, C.getCurrLocationContext());
831  Start =
833  } else {
834  os << "true";
835  Start =
836  PathDiagnosticLocation(B->getLHS(), SM, C.getCurrLocationContext());
837  End = ExecutionContinues(C);
838  }
839  } else {
840  assert(B->getOpcode() == BO_LOr);
841  os << "||"
842  << "' is ";
843 
844  if (*(Src->succ_begin() + 1) == Dst) {
845  os << "false";
846  Start =
847  PathDiagnosticLocation(B->getLHS(), SM, C.getCurrLocationContext());
848  End = ExecutionContinues(C);
849  } else {
850  os << "true";
851  End = PathDiagnosticLocation(B->getLHS(), SM, C.getCurrLocationContext());
852  Start =
854  }
855  }
856  return std::make_shared<PathDiagnosticControlFlowPiece>(Start, End,
857  os.str());
858 }
859 
860 void PathDiagnosticBuilder::generateMinimalDiagForBlockEdge(
861  PathDiagnosticConstruct &C, BlockEdge BE) const {
862  const SourceManager &SM = getSourceManager();
863  const LocationContext *LC = C.getCurrLocationContext();
864  const CFGBlock *Src = BE.getSrc();
865  const CFGBlock *Dst = BE.getDst();
866  const Stmt *T = Src->getTerminatorStmt();
867  if (!T)
868  return;
869 
870  auto Start = PathDiagnosticLocation::createBegin(T, SM, LC);
871  switch (T->getStmtClass()) {
872  default:
873  break;
874 
875  case Stmt::GotoStmtClass:
876  case Stmt::IndirectGotoStmtClass: {
877  if (const Stmt *S = C.getCurrentNode()->getNextStmtForDiagnostics())
878  C.getActivePath().push_front(generateDiagForGotoOP(C, S, Start));
879  break;
880  }
881 
882  case Stmt::SwitchStmtClass: {
883  C.getActivePath().push_front(generateDiagForSwitchOP(C, Dst, Start));
884  break;
885  }
886 
887  case Stmt::BreakStmtClass:
888  case Stmt::ContinueStmtClass: {
889  std::string sbuf;
890  llvm::raw_string_ostream os(sbuf);
891  PathDiagnosticLocation End = ExecutionContinues(os, C);
892  C.getActivePath().push_front(
893  std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, os.str()));
894  break;
895  }
896 
897  // Determine control-flow for ternary '?'.
898  case Stmt::BinaryConditionalOperatorClass:
899  case Stmt::ConditionalOperatorClass: {
900  std::string sbuf;
901  llvm::raw_string_ostream os(sbuf);
902  os << "'?' condition is ";
903 
904  if (*(Src->succ_begin() + 1) == Dst)
905  os << "false";
906  else
907  os << "true";
908 
909  PathDiagnosticLocation End = ExecutionContinues(C);
910 
911  if (const Stmt *S = End.asStmt())
912  End = getEnclosingStmtLocation(S, C.getCurrLocationContext());
913 
914  C.getActivePath().push_front(
915  std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, os.str()));
916  break;
917  }
918 
919  // Determine control-flow for short-circuited '&&' and '||'.
920  case Stmt::BinaryOperatorClass: {
921  if (!C.supportsLogicalOpControlFlow())
922  break;
923 
924  C.getActivePath().push_front(generateDiagForBinaryOP(C, T, Src, Dst));
925  break;
926  }
927 
928  case Stmt::DoStmtClass:
929  if (*(Src->succ_begin()) == Dst) {
930  std::string sbuf;
931  llvm::raw_string_ostream os(sbuf);
932 
933  os << "Loop condition is true. ";
934  PathDiagnosticLocation End = ExecutionContinues(os, C);
935 
936  if (const Stmt *S = End.asStmt())
937  End = getEnclosingStmtLocation(S, C.getCurrLocationContext());
938 
939  C.getActivePath().push_front(
940  std::make_shared<PathDiagnosticControlFlowPiece>(Start, End,
941  os.str()));
942  } else {
943  PathDiagnosticLocation End = ExecutionContinues(C);
944 
945  if (const Stmt *S = End.asStmt())
946  End = getEnclosingStmtLocation(S, C.getCurrLocationContext());
947 
948  C.getActivePath().push_front(
949  std::make_shared<PathDiagnosticControlFlowPiece>(
950  Start, End, "Loop condition is false. Exiting loop"));
951  }
952  break;
953 
954  case Stmt::WhileStmtClass:
955  case Stmt::ForStmtClass:
956  if (*(Src->succ_begin() + 1) == Dst) {
957  std::string sbuf;
958  llvm::raw_string_ostream os(sbuf);
959 
960  os << "Loop condition is false. ";
961  PathDiagnosticLocation End = ExecutionContinues(os, C);
962  if (const Stmt *S = End.asStmt())
963  End = getEnclosingStmtLocation(S, C.getCurrLocationContext());
964 
965  C.getActivePath().push_front(
966  std::make_shared<PathDiagnosticControlFlowPiece>(Start, End,
967  os.str()));
968  } else {
969  PathDiagnosticLocation End = ExecutionContinues(C);
970  if (const Stmt *S = End.asStmt())
971  End = getEnclosingStmtLocation(S, C.getCurrLocationContext());
972 
973  C.getActivePath().push_front(
974  std::make_shared<PathDiagnosticControlFlowPiece>(
975  Start, End, "Loop condition is true. Entering loop body"));
976  }
977 
978  break;
979 
980  case Stmt::IfStmtClass: {
981  PathDiagnosticLocation End = ExecutionContinues(C);
982 
983  if (const Stmt *S = End.asStmt())
984  End = getEnclosingStmtLocation(S, C.getCurrLocationContext());
985 
986  if (*(Src->succ_begin() + 1) == Dst)
987  C.getActivePath().push_front(
988  std::make_shared<PathDiagnosticControlFlowPiece>(
989  Start, End, "Taking false branch"));
990  else
991  C.getActivePath().push_front(
992  std::make_shared<PathDiagnosticControlFlowPiece>(
993  Start, End, "Taking true branch"));
994 
995  break;
996  }
997  }
998 }
999 
1000 //===----------------------------------------------------------------------===//
1001 // Functions for determining if a loop was executed 0 times.
1002 //===----------------------------------------------------------------------===//
1003 
1004 static bool isLoop(const Stmt *Term) {
1005  switch (Term->getStmtClass()) {
1006  case Stmt::ForStmtClass:
1007  case Stmt::WhileStmtClass:
1008  case Stmt::ObjCForCollectionStmtClass:
1009  case Stmt::CXXForRangeStmtClass:
1010  return true;
1011  default:
1012  // Note that we intentionally do not include do..while here.
1013  return false;
1014  }
1015 }
1016 
1017 static bool isJumpToFalseBranch(const BlockEdge *BE) {
1018  const CFGBlock *Src = BE->getSrc();
1019  assert(Src->succ_size() == 2);
1020  return (*(Src->succ_begin()+1) == BE->getDst());
1021 }
1022 
1023 static bool isContainedByStmt(const ParentMap &PM, const Stmt *S,
1024  const Stmt *SubS) {
1025  while (SubS) {
1026  if (SubS == S)
1027  return true;
1028  SubS = PM.getParent(SubS);
1029  }
1030  return false;
1031 }
1032 
1033 static const Stmt *getStmtBeforeCond(const ParentMap &PM, const Stmt *Term,
1034  const ExplodedNode *N) {
1035  while (N) {
1036  Optional<StmtPoint> SP = N->getLocation().getAs<StmtPoint>();
1037  if (SP) {
1038  const Stmt *S = SP->getStmt();
1039  if (!isContainedByStmt(PM, Term, S))
1040  return S;
1041  }
1042  N = N->getFirstPred();
1043  }
1044  return nullptr;
1045 }
1046 
1047 static bool isInLoopBody(const ParentMap &PM, const Stmt *S, const Stmt *Term) {
1048  const Stmt *LoopBody = nullptr;
1049  switch (Term->getStmtClass()) {
1050  case Stmt::CXXForRangeStmtClass: {
1051  const auto *FR = cast<CXXForRangeStmt>(Term);
1052  if (isContainedByStmt(PM, FR->getInc(), S))
1053  return true;
1054  if (isContainedByStmt(PM, FR->getLoopVarStmt(), S))
1055  return true;
1056  LoopBody = FR->getBody();
1057  break;
1058  }
1059  case Stmt::ForStmtClass: {
1060  const auto *FS = cast<ForStmt>(Term);
1061  if (isContainedByStmt(PM, FS->getInc(), S))
1062  return true;
1063  LoopBody = FS->getBody();
1064  break;
1065  }
1066  case Stmt::ObjCForCollectionStmtClass: {
1067  const auto *FC = cast<ObjCForCollectionStmt>(Term);
1068  LoopBody = FC->getBody();
1069  break;
1070  }
1071  case Stmt::WhileStmtClass:
1072  LoopBody = cast<WhileStmt>(Term)->getBody();
1073  break;
1074  default:
1075  return false;
1076  }
1077  return isContainedByStmt(PM, LoopBody, S);
1078 }
1079 
1080 /// Adds a sanitized control-flow diagnostic edge to a path.
1081 static void addEdgeToPath(PathPieces &path,
1082  PathDiagnosticLocation &PrevLoc,
1083  PathDiagnosticLocation NewLoc) {
1084  if (!NewLoc.isValid())
1085  return;
1086 
1087  SourceLocation NewLocL = NewLoc.asLocation();
1088  if (NewLocL.isInvalid())
1089  return;
1090 
1091  if (!PrevLoc.isValid() || !PrevLoc.asLocation().isValid()) {
1092  PrevLoc = NewLoc;
1093  return;
1094  }
1095 
1096  // Ignore self-edges, which occur when there are multiple nodes at the same
1097  // statement.
1098  if (NewLoc.asStmt() && NewLoc.asStmt() == PrevLoc.asStmt())
1099  return;
1100 
1101  path.push_front(
1102  std::make_shared<PathDiagnosticControlFlowPiece>(NewLoc, PrevLoc));
1103  PrevLoc = NewLoc;
1104 }
1105 
1106 /// A customized wrapper for CFGBlock::getTerminatorCondition()
1107 /// which returns the element for ObjCForCollectionStmts.
1108 static const Stmt *getTerminatorCondition(const CFGBlock *B) {
1109  const Stmt *S = B->getTerminatorCondition();
1110  if (const auto *FS = dyn_cast_or_null<ObjCForCollectionStmt>(S))
1111  return FS->getElement();
1112  return S;
1113 }
1114 
1115 constexpr llvm::StringLiteral StrEnteringLoop = "Entering loop body";
1116 constexpr llvm::StringLiteral StrLoopBodyZero = "Loop body executed 0 times";
1117 constexpr llvm::StringLiteral StrLoopRangeEmpty =
1118  "Loop body skipped when range is empty";
1119 constexpr llvm::StringLiteral StrLoopCollectionEmpty =
1120  "Loop body skipped when collection is empty";
1121 
1122 static std::unique_ptr<FilesToLineNumsMap>
1123 findExecutedLines(const SourceManager &SM, const ExplodedNode *N);
1124 
1125 void PathDiagnosticBuilder::generatePathDiagnosticsForNode(
1126  PathDiagnosticConstruct &C, PathDiagnosticLocation &PrevLoc) const {
1127  ProgramPoint P = C.getCurrentNode()->getLocation();
1128  const SourceManager &SM = getSourceManager();
1129 
1130  // Have we encountered an entrance to a call? It may be
1131  // the case that we have not encountered a matching
1132  // call exit before this point. This means that the path
1133  // terminated within the call itself.
1134  if (auto CE = P.getAs<CallEnter>()) {
1135 
1136  if (C.shouldAddPathEdges()) {
1137  // Add an edge to the start of the function.
1138  const StackFrameContext *CalleeLC = CE->getCalleeContext();
1139  const Decl *D = CalleeLC->getDecl();
1140  // Add the edge only when the callee has body. We jump to the beginning
1141  // of the *declaration*, however we expect it to be followed by the
1142  // body. This isn't the case for autosynthesized property accessors in
1143  // Objective-C. No need for a similar extra check for CallExit points
1144  // because the exit edge comes from a statement (i.e. return),
1145  // not from declaration.
1146  if (D->hasBody())
1147  addEdgeToPath(C.getActivePath(), PrevLoc,
1149  }
1150 
1151  // Did we visit an entire call?
1152  bool VisitedEntireCall = C.PD->isWithinCall();
1153  C.PD->popActivePath();
1154 
1155  PathDiagnosticCallPiece *Call;
1156  if (VisitedEntireCall) {
1157  Call = cast<PathDiagnosticCallPiece>(C.getActivePath().front().get());
1158  } else {
1159  // The path terminated within a nested location context, create a new
1160  // call piece to encapsulate the rest of the path pieces.
1161  const Decl *Caller = CE->getLocationContext()->getDecl();
1162  Call = PathDiagnosticCallPiece::construct(C.getActivePath(), Caller);
1163  assert(C.getActivePath().size() == 1 &&
1164  C.getActivePath().front().get() == Call);
1165 
1166  // Since we just transferred the path over to the call piece, reset the
1167  // mapping of the active path to the current location context.
1168  assert(C.isInLocCtxMap(&C.getActivePath()) &&
1169  "When we ascend to a previously unvisited call, the active path's "
1170  "address shouldn't change, but rather should be compacted into "
1171  "a single CallEvent!");
1172  C.updateLocCtxMap(&C.getActivePath(), C.getCurrLocationContext());
1173 
1174  // Record the location context mapping for the path within the call.
1175  assert(!C.isInLocCtxMap(&Call->path) &&
1176  "When we ascend to a previously unvisited call, this must be the "
1177  "first time we encounter the caller context!");
1178  C.updateLocCtxMap(&Call->path, CE->getCalleeContext());
1179  }
1180  Call->setCallee(*CE, SM);
1181 
1182  // Update the previous location in the active path.
1183  PrevLoc = Call->getLocation();
1184 
1185  if (!C.CallStack.empty()) {
1186  assert(C.CallStack.back().first == Call);
1187  C.CallStack.pop_back();
1188  }
1189  return;
1190  }
1191 
1192  assert(C.getCurrLocationContext() == C.getLocationContextForActivePath() &&
1193  "The current position in the bug path is out of sync with the "
1194  "location context associated with the active path!");
1195 
1196  // Have we encountered an exit from a function call?
1197  if (Optional<CallExitEnd> CE = P.getAs<CallExitEnd>()) {
1198 
1199  // We are descending into a call (backwards). Construct
1200  // a new call piece to contain the path pieces for that call.
1202  // Record the mapping from call piece to LocationContext.
1203  assert(!C.isInLocCtxMap(&Call->path) &&
1204  "We just entered a call, this must've been the first time we "
1205  "encounter its context!");
1206  C.updateLocCtxMap(&Call->path, CE->getCalleeContext());
1207 
1208  if (C.shouldAddPathEdges()) {
1209  // Add the edge to the return site.
1210  addEdgeToPath(C.getActivePath(), PrevLoc, Call->callReturn);
1211  PrevLoc.invalidate();
1212  }
1213 
1214  auto *P = Call.get();
1215  C.getActivePath().push_front(std::move(Call));
1216 
1217  // Make the contents of the call the active path for now.
1218  C.PD->pushActivePath(&P->path);
1219  C.CallStack.push_back(CallWithEntry(P, C.getCurrentNode()));
1220  return;
1221  }
1222 
1223  if (auto PS = P.getAs<PostStmt>()) {
1224  if (!C.shouldAddPathEdges())
1225  return;
1226 
1227  // Add an edge. If this is an ObjCForCollectionStmt do
1228  // not add an edge here as it appears in the CFG both
1229  // as a terminator and as a terminator condition.
1230  if (!isa<ObjCForCollectionStmt>(PS->getStmt())) {
1231  PathDiagnosticLocation L =
1232  PathDiagnosticLocation(PS->getStmt(), SM, C.getCurrLocationContext());
1233  addEdgeToPath(C.getActivePath(), PrevLoc, L);
1234  }
1235 
1236  } else if (auto BE = P.getAs<BlockEdge>()) {
1237 
1238  if (C.shouldAddControlNotes()) {
1239  generateMinimalDiagForBlockEdge(C, *BE);
1240  }
1241 
1242  if (!C.shouldAddPathEdges()) {
1243  return;
1244  }
1245 
1246  // Are we jumping to the head of a loop? Add a special diagnostic.
1247  if (const Stmt *Loop = BE->getSrc()->getLoopTarget()) {
1248  PathDiagnosticLocation L(Loop, SM, C.getCurrLocationContext());
1249  const Stmt *Body = nullptr;
1250 
1251  if (const auto *FS = dyn_cast<ForStmt>(Loop))
1252  Body = FS->getBody();
1253  else if (const auto *WS = dyn_cast<WhileStmt>(Loop))
1254  Body = WS->getBody();
1255  else if (const auto *OFS = dyn_cast<ObjCForCollectionStmt>(Loop)) {
1256  Body = OFS->getBody();
1257  } else if (const auto *FRS = dyn_cast<CXXForRangeStmt>(Loop)) {
1258  Body = FRS->getBody();
1259  }
1260  // do-while statements are explicitly excluded here
1261 
1262  auto p = std::make_shared<PathDiagnosticEventPiece>(
1263  L, "Looping back to the head of the loop");
1264  p->setPrunable(true);
1265 
1266  addEdgeToPath(C.getActivePath(), PrevLoc, p->getLocation());
1267  // We might've added a very similar control node already
1268  if (!C.shouldAddControlNotes()) {
1269  C.getActivePath().push_front(std::move(p));
1270  }
1271 
1272  if (const auto *CS = dyn_cast_or_null<CompoundStmt>(Body)) {
1273  addEdgeToPath(C.getActivePath(), PrevLoc,
1275  }
1276  }
1277 
1278  const CFGBlock *BSrc = BE->getSrc();
1279  const ParentMap &PM = C.getParentMap();
1280 
1281  if (const Stmt *Term = BSrc->getTerminatorStmt()) {
1282  // Are we jumping past the loop body without ever executing the
1283  // loop (because the condition was false)?
1284  if (isLoop(Term)) {
1285  const Stmt *TermCond = getTerminatorCondition(BSrc);
1286  bool IsInLoopBody = isInLoopBody(
1287  PM, getStmtBeforeCond(PM, TermCond, C.getCurrentNode()), Term);
1288 
1289  StringRef str;
1290 
1291  if (isJumpToFalseBranch(&*BE)) {
1292  if (!IsInLoopBody) {
1293  if (isa<ObjCForCollectionStmt>(Term)) {
1294  str = StrLoopCollectionEmpty;
1295  } else if (isa<CXXForRangeStmt>(Term)) {
1296  str = StrLoopRangeEmpty;
1297  } else {
1298  str = StrLoopBodyZero;
1299  }
1300  }
1301  } else {
1302  str = StrEnteringLoop;
1303  }
1304 
1305  if (!str.empty()) {
1306  PathDiagnosticLocation L(TermCond ? TermCond : Term, SM,
1307  C.getCurrLocationContext());
1308  auto PE = std::make_shared<PathDiagnosticEventPiece>(L, str);
1309  PE->setPrunable(true);
1310  addEdgeToPath(C.getActivePath(), PrevLoc, PE->getLocation());
1311 
1312  // We might've added a very similar control node already
1313  if (!C.shouldAddControlNotes()) {
1314  C.getActivePath().push_front(std::move(PE));
1315  }
1316  }
1317  } else if (isa<BreakStmt, ContinueStmt, GotoStmt>(Term)) {
1318  PathDiagnosticLocation L(Term, SM, C.getCurrLocationContext());
1319  addEdgeToPath(C.getActivePath(), PrevLoc, L);
1320  }
1321  }
1322  }
1323 }
1324 
1325 static std::unique_ptr<PathDiagnostic>
1326 generateDiagnosticForBasicReport(const BasicBugReport *R) {
1327  const BugType &BT = R->getBugType();
1328  return std::make_unique<PathDiagnostic>(
1329  BT.getCheckerName(), R->getDeclWithIssue(), BT.getDescription(),
1330  R->getDescription(), R->getShortDescription(/*UseFallback=*/false),
1331  BT.getCategory(), R->getUniqueingLocation(), R->getUniqueingDecl(),
1332  std::make_unique<FilesToLineNumsMap>());
1333 }
1334 
1335 static std::unique_ptr<PathDiagnostic>
1336 generateEmptyDiagnosticForReport(const PathSensitiveBugReport *R,
1337  const SourceManager &SM) {
1338  const BugType &BT = R->getBugType();
1339  return std::make_unique<PathDiagnostic>(
1340  BT.getCheckerName(), R->getDeclWithIssue(), BT.getDescription(),
1341  R->getDescription(), R->getShortDescription(/*UseFallback=*/false),
1342  BT.getCategory(), R->getUniqueingLocation(), R->getUniqueingDecl(),
1343  findExecutedLines(SM, R->getErrorNode()));
1344 }
1345 
1346 static const Stmt *getStmtParent(const Stmt *S, const ParentMap &PM) {
1347  if (!S)
1348  return nullptr;
1349 
1350  while (true) {
1351  S = PM.getParentIgnoreParens(S);
1352 
1353  if (!S)
1354  break;
1355 
1356  if (isa<FullExpr, CXXBindTemporaryExpr, SubstNonTypeTemplateParmExpr>(S))
1357  continue;
1358 
1359  break;
1360  }
1361 
1362  return S;
1363 }
1364 
1365 static bool isConditionForTerminator(const Stmt *S, const Stmt *Cond) {
1366  switch (S->getStmtClass()) {
1367  case Stmt::BinaryOperatorClass: {
1368  const auto *BO = cast<BinaryOperator>(S);
1369  if (!BO->isLogicalOp())
1370  return false;
1371  return BO->getLHS() == Cond || BO->getRHS() == Cond;
1372  }
1373  case Stmt::IfStmtClass:
1374  return cast<IfStmt>(S)->getCond() == Cond;
1375  case Stmt::ForStmtClass:
1376  return cast<ForStmt>(S)->getCond() == Cond;
1377  case Stmt::WhileStmtClass:
1378  return cast<WhileStmt>(S)->getCond() == Cond;
1379  case Stmt::DoStmtClass:
1380  return cast<DoStmt>(S)->getCond() == Cond;
1381  case Stmt::ChooseExprClass:
1382  return cast<ChooseExpr>(S)->getCond() == Cond;
1383  case Stmt::IndirectGotoStmtClass:
1384  return cast<IndirectGotoStmt>(S)->getTarget() == Cond;
1385  case Stmt::SwitchStmtClass:
1386  return cast<SwitchStmt>(S)->getCond() == Cond;
1387  case Stmt::BinaryConditionalOperatorClass:
1388  return cast<BinaryConditionalOperator>(S)->getCond() == Cond;
1389  case Stmt::ConditionalOperatorClass: {
1390  const auto *CO = cast<ConditionalOperator>(S);
1391  return CO->getCond() == Cond ||
1392  CO->getLHS() == Cond ||
1393  CO->getRHS() == Cond;
1394  }
1395  case Stmt::ObjCForCollectionStmtClass:
1396  return cast<ObjCForCollectionStmt>(S)->getElement() == Cond;
1397  case Stmt::CXXForRangeStmtClass: {
1398  const auto *FRS = cast<CXXForRangeStmt>(S);
1399  return FRS->getCond() == Cond || FRS->getRangeInit() == Cond;
1400  }
1401  default:
1402  return false;
1403  }
1404 }
1405 
1406 static bool isIncrementOrInitInForLoop(const Stmt *S, const Stmt *FL) {
1407  if (const auto *FS = dyn_cast<ForStmt>(FL))
1408  return FS->getInc() == S || FS->getInit() == S;
1409  if (const auto *FRS = dyn_cast<CXXForRangeStmt>(FL))
1410  return FRS->getInc() == S || FRS->getRangeStmt() == S ||
1411  FRS->getLoopVarStmt() || FRS->getRangeInit() == S;
1412  return false;
1413 }
1414 
1416 
1417 /// Adds synthetic edges from top-level statements to their subexpressions.
1418 ///
1419 /// This avoids a "swoosh" effect, where an edge from a top-level statement A
1420 /// points to a sub-expression B.1 that's not at the start of B. In these cases,
1421 /// we'd like to see an edge from A to B, then another one from B to B.1.
1422 static void addContextEdges(PathPieces &pieces, const LocationContext *LC) {
1423  const ParentMap &PM = LC->getParentMap();
1424  PathPieces::iterator Prev = pieces.end();
1425  for (PathPieces::iterator I = pieces.begin(), E = Prev; I != E;
1426  Prev = I, ++I) {
1427  auto *Piece = dyn_cast<PathDiagnosticControlFlowPiece>(I->get());
1428 
1429  if (!Piece)
1430  continue;
1431 
1432  PathDiagnosticLocation SrcLoc = Piece->getStartLocation();
1434 
1435  PathDiagnosticLocation NextSrcContext = SrcLoc;
1436  const Stmt *InnerStmt = nullptr;
1437  while (NextSrcContext.isValid() && NextSrcContext.asStmt() != InnerStmt) {
1438  SrcContexts.push_back(NextSrcContext);
1439  InnerStmt = NextSrcContext.asStmt();
1440  NextSrcContext = getEnclosingStmtLocation(InnerStmt, LC,
1441  /*allowNested=*/true);
1442  }
1443 
1444  // Repeatedly split the edge as necessary.
1445  // This is important for nested logical expressions (||, &&, ?:) where we
1446  // want to show all the levels of context.
1447  while (true) {
1448  const Stmt *Dst = Piece->getEndLocation().getStmtOrNull();
1449 
1450  // We are looking at an edge. Is the destination within a larger
1451  // expression?
1452  PathDiagnosticLocation DstContext =
1453  getEnclosingStmtLocation(Dst, LC, /*allowNested=*/true);
1454  if (!DstContext.isValid() || DstContext.asStmt() == Dst)
1455  break;
1456 
1457  // If the source is in the same context, we're already good.
1458  if (llvm::is_contained(SrcContexts, DstContext))
1459  break;
1460 
1461  // Update the subexpression node to point to the context edge.
1462  Piece->setStartLocation(DstContext);
1463 
1464  // Try to extend the previous edge if it's at the same level as the source
1465  // context.
1466  if (Prev != E) {
1467  auto *PrevPiece = dyn_cast<PathDiagnosticControlFlowPiece>(Prev->get());
1468 
1469  if (PrevPiece) {
1470  if (const Stmt *PrevSrc =
1471  PrevPiece->getStartLocation().getStmtOrNull()) {
1472  const Stmt *PrevSrcParent = getStmtParent(PrevSrc, PM);
1473  if (PrevSrcParent ==
1474  getStmtParent(DstContext.getStmtOrNull(), PM)) {
1475  PrevPiece->setEndLocation(DstContext);
1476  break;
1477  }
1478  }
1479  }
1480  }
1481 
1482  // Otherwise, split the current edge into a context edge and a
1483  // subexpression edge. Note that the context statement may itself have
1484  // context.
1485  auto P =
1486  std::make_shared<PathDiagnosticControlFlowPiece>(SrcLoc, DstContext);
1487  Piece = P.get();
1488  I = pieces.insert(I, std::move(P));
1489  }
1490  }
1491 }
1492 
1493 /// Move edges from a branch condition to a branch target
1494 /// when the condition is simple.
1495 ///
1496 /// This restructures some of the work of addContextEdges. That function
1497 /// creates edges this may destroy, but they work together to create a more
1498 /// aesthetically set of edges around branches. After the call to
1499 /// addContextEdges, we may have (1) an edge to the branch, (2) an edge from
1500 /// the branch to the branch condition, and (3) an edge from the branch
1501 /// condition to the branch target. We keep (1), but may wish to remove (2)
1502 /// and move the source of (3) to the branch if the branch condition is simple.
1503 static void simplifySimpleBranches(PathPieces &pieces) {
1504  for (PathPieces::iterator I = pieces.begin(), E = pieces.end(); I != E; ++I) {
1505  const auto *PieceI = dyn_cast<PathDiagnosticControlFlowPiece>(I->get());
1506 
1507  if (!PieceI)
1508  continue;
1509 
1510  const Stmt *s1Start = PieceI->getStartLocation().getStmtOrNull();
1511  const Stmt *s1End = PieceI->getEndLocation().getStmtOrNull();
1512 
1513  if (!s1Start || !s1End)
1514  continue;
1515 
1516  PathPieces::iterator NextI = I; ++NextI;
1517  if (NextI == E)
1518  break;
1519 
1520  PathDiagnosticControlFlowPiece *PieceNextI = nullptr;
1521 
1522  while (true) {
1523  if (NextI == E)
1524  break;
1525 
1526  const auto *EV = dyn_cast<PathDiagnosticEventPiece>(NextI->get());
1527  if (EV) {
1528  StringRef S = EV->getString();
1529  if (S == StrEnteringLoop || S == StrLoopBodyZero ||
1531  ++NextI;
1532  continue;
1533  }
1534  break;
1535  }
1536 
1537  PieceNextI = dyn_cast<PathDiagnosticControlFlowPiece>(NextI->get());
1538  break;
1539  }
1540 
1541  if (!PieceNextI)
1542  continue;
1543 
1544  const Stmt *s2Start = PieceNextI->getStartLocation().getStmtOrNull();
1545  const Stmt *s2End = PieceNextI->getEndLocation().getStmtOrNull();
1546 
1547  if (!s2Start || !s2End || s1End != s2Start)
1548  continue;
1549 
1550  // We only perform this transformation for specific branch kinds.
1551  // We don't want to do this for do..while, for example.
1553  CXXForRangeStmt>(s1Start))
1554  continue;
1555 
1556  // Is s1End the branch condition?
1557  if (!isConditionForTerminator(s1Start, s1End))
1558  continue;
1559 
1560  // Perform the hoisting by eliminating (2) and changing the start
1561  // location of (3).
1562  PieceNextI->setStartLocation(PieceI->getStartLocation());
1563  I = pieces.erase(I);
1564  }
1565 }
1566 
1567 /// Returns the number of bytes in the given (character-based) SourceRange.
1568 ///
1569 /// If the locations in the range are not on the same line, returns None.
1570 ///
1571 /// Note that this does not do a precise user-visible character or column count.
1573  SourceRange Range) {
1574  SourceRange ExpansionRange(SM.getExpansionLoc(Range.getBegin()),
1575  SM.getExpansionRange(Range.getEnd()).getEnd());
1576 
1577  FileID FID = SM.getFileID(ExpansionRange.getBegin());
1578  if (FID != SM.getFileID(ExpansionRange.getEnd()))
1579  return None;
1580 
1581  Optional<MemoryBufferRef> Buffer = SM.getBufferOrNone(FID);
1582  if (!Buffer)
1583  return None;
1584 
1585  unsigned BeginOffset = SM.getFileOffset(ExpansionRange.getBegin());
1586  unsigned EndOffset = SM.getFileOffset(ExpansionRange.getEnd());
1587  StringRef Snippet = Buffer->getBuffer().slice(BeginOffset, EndOffset);
1588 
1589  // We're searching the raw bytes of the buffer here, which might include
1590  // escaped newlines and such. That's okay; we're trying to decide whether the
1591  // SourceRange is covering a large or small amount of space in the user's
1592  // editor.
1593  if (Snippet.find_first_of("\r\n") != StringRef::npos)
1594  return None;
1595 
1596  // This isn't Unicode-aware, but it doesn't need to be.
1597  return Snippet.size();
1598 }
1599 
1600 /// \sa getLengthOnSingleLine(SourceManager, SourceRange)
1602  const Stmt *S) {
1603  return getLengthOnSingleLine(SM, S->getSourceRange());
1604 }
1605 
1606 /// Eliminate two-edge cycles created by addContextEdges().
1607 ///
1608 /// Once all the context edges are in place, there are plenty of cases where
1609 /// there's a single edge from a top-level statement to a subexpression,
1610 /// followed by a single path note, and then a reverse edge to get back out to
1611 /// the top level. If the statement is simple enough, the subexpression edges
1612 /// just add noise and make it harder to understand what's going on.
1613 ///
1614 /// This function only removes edges in pairs, because removing only one edge
1615 /// might leave other edges dangling.
1616 ///
1617 /// This will not remove edges in more complicated situations:
1618 /// - if there is more than one "hop" leading to or from a subexpression.
1619 /// - if there is an inlined call between the edges instead of a single event.
1620 /// - if the whole statement is large enough that having subexpression arrows
1621 /// might be helpful.
1622 static void removeContextCycles(PathPieces &Path, const SourceManager &SM) {
1623  for (PathPieces::iterator I = Path.begin(), E = Path.end(); I != E; ) {
1624  // Pattern match the current piece and its successor.
1625  const auto *PieceI = dyn_cast<PathDiagnosticControlFlowPiece>(I->get());
1626 
1627  if (!PieceI) {
1628  ++I;
1629  continue;
1630  }
1631 
1632  const Stmt *s1Start = PieceI->getStartLocation().getStmtOrNull();
1633  const Stmt *s1End = PieceI->getEndLocation().getStmtOrNull();
1634 
1635  PathPieces::iterator NextI = I; ++NextI;
1636  if (NextI == E)
1637  break;
1638 
1639  const auto *PieceNextI =
1640  dyn_cast<PathDiagnosticControlFlowPiece>(NextI->get());
1641 
1642  if (!PieceNextI) {
1643  if (isa<PathDiagnosticEventPiece>(NextI->get())) {
1644  ++NextI;
1645  if (NextI == E)
1646  break;
1647  PieceNextI = dyn_cast<PathDiagnosticControlFlowPiece>(NextI->get());
1648  }
1649 
1650  if (!PieceNextI) {
1651  ++I;
1652  continue;
1653  }
1654  }
1655 
1656  const Stmt *s2Start = PieceNextI->getStartLocation().getStmtOrNull();
1657  const Stmt *s2End = PieceNextI->getEndLocation().getStmtOrNull();
1658 
1659  if (s1Start && s2Start && s1Start == s2End && s2Start == s1End) {
1660  const size_t MAX_SHORT_LINE_LENGTH = 80;
1661  Optional<size_t> s1Length = getLengthOnSingleLine(SM, s1Start);
1662  if (s1Length && *s1Length <= MAX_SHORT_LINE_LENGTH) {
1663  Optional<size_t> s2Length = getLengthOnSingleLine(SM, s2Start);
1664  if (s2Length && *s2Length <= MAX_SHORT_LINE_LENGTH) {
1665  Path.erase(I);
1666  I = Path.erase(NextI);
1667  continue;
1668  }
1669  }
1670  }
1671 
1672  ++I;
1673  }
1674 }
1675 
1676 /// Return true if X is contained by Y.
1677 static bool lexicalContains(const ParentMap &PM, const Stmt *X, const Stmt *Y) {
1678  while (X) {
1679  if (X == Y)
1680  return true;
1681  X = PM.getParent(X);
1682  }
1683  return false;
1684 }
1685 
1686 // Remove short edges on the same line less than 3 columns in difference.
1687 static void removePunyEdges(PathPieces &path, const SourceManager &SM,
1688  const ParentMap &PM) {
1689  bool erased = false;
1690 
1691  for (PathPieces::iterator I = path.begin(), E = path.end(); I != E;
1692  erased ? I : ++I) {
1693  erased = false;
1694 
1695  const auto *PieceI = dyn_cast<PathDiagnosticControlFlowPiece>(I->get());
1696 
1697  if (!PieceI)
1698  continue;
1699 
1700  const Stmt *start = PieceI->getStartLocation().getStmtOrNull();
1701  const Stmt *end = PieceI->getEndLocation().getStmtOrNull();
1702 
1703  if (!start || !end)
1704  continue;
1705 
1706  const Stmt *endParent = PM.getParent(end);
1707  if (!endParent)
1708  continue;
1709 
1710  if (isConditionForTerminator(end, endParent))
1711  continue;
1712 
1713  SourceLocation FirstLoc = start->getBeginLoc();
1714  SourceLocation SecondLoc = end->getBeginLoc();
1715 
1716  if (!SM.isWrittenInSameFile(FirstLoc, SecondLoc))
1717  continue;
1718  if (SM.isBeforeInTranslationUnit(SecondLoc, FirstLoc))
1719  std::swap(SecondLoc, FirstLoc);
1720 
1721  SourceRange EdgeRange(FirstLoc, SecondLoc);
1722  Optional<size_t> ByteWidth = getLengthOnSingleLine(SM, EdgeRange);
1723 
1724  // If the statements are on different lines, continue.
1725  if (!ByteWidth)
1726  continue;
1727 
1728  const size_t MAX_PUNY_EDGE_LENGTH = 2;
1729  if (*ByteWidth <= MAX_PUNY_EDGE_LENGTH) {
1730  // FIXME: There are enough /bytes/ between the endpoints of the edge, but
1731  // there might not be enough /columns/. A proper user-visible column count
1732  // is probably too expensive, though.
1733  I = path.erase(I);
1734  erased = true;
1735  continue;
1736  }
1737  }
1738 }
1739 
1740 static void removeIdenticalEvents(PathPieces &path) {
1741  for (PathPieces::iterator I = path.begin(), E = path.end(); I != E; ++I) {
1742  const auto *PieceI = dyn_cast<PathDiagnosticEventPiece>(I->get());
1743 
1744  if (!PieceI)
1745  continue;
1746 
1747  PathPieces::iterator NextI = I; ++NextI;
1748  if (NextI == E)
1749  return;
1750 
1751  const auto *PieceNextI = dyn_cast<PathDiagnosticEventPiece>(NextI->get());
1752 
1753  if (!PieceNextI)
1754  continue;
1755 
1756  // Erase the second piece if it has the same exact message text.
1757  if (PieceI->getString() == PieceNextI->getString()) {
1758  path.erase(NextI);
1759  }
1760  }
1761 }
1762 
1763 static bool optimizeEdges(const PathDiagnosticConstruct &C, PathPieces &path,
1764  OptimizedCallsSet &OCS) {
1765  bool hasChanges = false;
1766  const LocationContext *LC = C.getLocationContextFor(&path);
1767  assert(LC);
1768  const ParentMap &PM = LC->getParentMap();
1769  const SourceManager &SM = C.getSourceManager();
1770 
1771  for (PathPieces::iterator I = path.begin(), E = path.end(); I != E; ) {
1772  // Optimize subpaths.
1773  if (auto *CallI = dyn_cast<PathDiagnosticCallPiece>(I->get())) {
1774  // Record the fact that a call has been optimized so we only do the
1775  // effort once.
1776  if (!OCS.count(CallI)) {
1777  while (optimizeEdges(C, CallI->path, OCS)) {
1778  }
1779  OCS.insert(CallI);
1780  }
1781  ++I;
1782  continue;
1783  }
1784 
1785  // Pattern match the current piece and its successor.
1786  auto *PieceI = dyn_cast<PathDiagnosticControlFlowPiece>(I->get());
1787 
1788  if (!PieceI) {
1789  ++I;
1790  continue;
1791  }
1792 
1793  const Stmt *s1Start = PieceI->getStartLocation().getStmtOrNull();
1794  const Stmt *s1End = PieceI->getEndLocation().getStmtOrNull();
1795  const Stmt *level1 = getStmtParent(s1Start, PM);
1796  const Stmt *level2 = getStmtParent(s1End, PM);
1797 
1798  PathPieces::iterator NextI = I; ++NextI;
1799  if (NextI == E)
1800  break;
1801 
1802  const auto *PieceNextI = dyn_cast<PathDiagnosticControlFlowPiece>(NextI->get());
1803 
1804  if (!PieceNextI) {
1805  ++I;
1806  continue;
1807  }
1808 
1809  const Stmt *s2Start = PieceNextI->getStartLocation().getStmtOrNull();
1810  const Stmt *s2End = PieceNextI->getEndLocation().getStmtOrNull();
1811  const Stmt *level3 = getStmtParent(s2Start, PM);
1812  const Stmt *level4 = getStmtParent(s2End, PM);
1813 
1814  // Rule I.
1815  //
1816  // If we have two consecutive control edges whose end/begin locations
1817  // are at the same level (e.g. statements or top-level expressions within
1818  // a compound statement, or siblings share a single ancestor expression),
1819  // then merge them if they have no interesting intermediate event.
1820  //
1821  // For example:
1822  //
1823  // (1.1 -> 1.2) -> (1.2 -> 1.3) becomes (1.1 -> 1.3) because the common
1824  // parent is '1'. Here 'x.y.z' represents the hierarchy of statements.
1825  //
1826  // NOTE: this will be limited later in cases where we add barriers
1827  // to prevent this optimization.
1828  if (level1 && level1 == level2 && level1 == level3 && level1 == level4) {
1829  PieceI->setEndLocation(PieceNextI->getEndLocation());
1830  path.erase(NextI);
1831  hasChanges = true;
1832  continue;
1833  }
1834 
1835  // Rule II.
1836  //
1837  // Eliminate edges between subexpressions and parent expressions
1838  // when the subexpression is consumed.
1839  //
1840  // NOTE: this will be limited later in cases where we add barriers
1841  // to prevent this optimization.
1842  if (s1End && s1End == s2Start && level2) {
1843  bool removeEdge = false;
1844  // Remove edges into the increment or initialization of a
1845  // loop that have no interleaving event. This means that
1846  // they aren't interesting.
1847  if (isIncrementOrInitInForLoop(s1End, level2))
1848  removeEdge = true;
1849  // Next only consider edges that are not anchored on
1850  // the condition of a terminator. This are intermediate edges
1851  // that we might want to trim.
1852  else if (!isConditionForTerminator(level2, s1End)) {
1853  // Trim edges on expressions that are consumed by
1854  // the parent expression.
1855  if (isa<Expr>(s1End) && PM.isConsumedExpr(cast<Expr>(s1End))) {
1856  removeEdge = true;
1857  }
1858  // Trim edges where a lexical containment doesn't exist.
1859  // For example:
1860  //
1861  // X -> Y -> Z
1862  //
1863  // If 'Z' lexically contains Y (it is an ancestor) and
1864  // 'X' does not lexically contain Y (it is a descendant OR
1865  // it has no lexical relationship at all) then trim.
1866  //
1867  // This can eliminate edges where we dive into a subexpression
1868  // and then pop back out, etc.
1869  else if (s1Start && s2End &&
1870  lexicalContains(PM, s2Start, s2End) &&
1871  !lexicalContains(PM, s1End, s1Start)) {
1872  removeEdge = true;
1873  }
1874  // Trim edges from a subexpression back to the top level if the
1875  // subexpression is on a different line.
1876  //
1877  // A.1 -> A -> B
1878  // becomes
1879  // A.1 -> B
1880  //
1881  // These edges just look ugly and don't usually add anything.
1882  else if (s1Start && s2End &&
1883  lexicalContains(PM, s1Start, s1End)) {
1884  SourceRange EdgeRange(PieceI->getEndLocation().asLocation(),
1885  PieceI->getStartLocation().asLocation());
1886  if (!getLengthOnSingleLine(SM, EdgeRange).hasValue())
1887  removeEdge = true;
1888  }
1889  }
1890 
1891  if (removeEdge) {
1892  PieceI->setEndLocation(PieceNextI->getEndLocation());
1893  path.erase(NextI);
1894  hasChanges = true;
1895  continue;
1896  }
1897  }
1898 
1899  // Optimize edges for ObjC fast-enumeration loops.
1900  //
1901  // (X -> collection) -> (collection -> element)
1902  //
1903  // becomes:
1904  //
1905  // (X -> element)
1906  if (s1End == s2Start) {
1907  const auto *FS = dyn_cast_or_null<ObjCForCollectionStmt>(level3);
1908  if (FS && FS->getCollection()->IgnoreParens() == s2Start &&
1909  s2End == FS->getElement()) {
1910  PieceI->setEndLocation(PieceNextI->getEndLocation());
1911  path.erase(NextI);
1912  hasChanges = true;
1913  continue;
1914  }
1915  }
1916 
1917  // No changes at this index? Move to the next one.
1918  ++I;
1919  }
1920 
1921  if (!hasChanges) {
1922  // Adjust edges into subexpressions to make them more uniform
1923  // and aesthetically pleasing.
1924  addContextEdges(path, LC);
1925  // Remove "cyclical" edges that include one or more context edges.
1926  removeContextCycles(path, SM);
1927  // Hoist edges originating from branch conditions to branches
1928  // for simple branches.
1929  simplifySimpleBranches(path);
1930  // Remove any puny edges left over after primary optimization pass.
1931  removePunyEdges(path, SM, PM);
1932  // Remove identical events.
1933  removeIdenticalEvents(path);
1934  }
1935 
1936  return hasChanges;
1937 }
1938 
1939 /// Drop the very first edge in a path, which should be a function entry edge.
1940 ///
1941 /// If the first edge is not a function entry edge (say, because the first
1942 /// statement had an invalid source location), this function does nothing.
1943 // FIXME: We should just generate invalid edges anyway and have the optimizer
1944 // deal with them.
1945 static void dropFunctionEntryEdge(const PathDiagnosticConstruct &C,
1946  PathPieces &Path) {
1947  const auto *FirstEdge =
1948  dyn_cast<PathDiagnosticControlFlowPiece>(Path.front().get());
1949  if (!FirstEdge)
1950  return;
1951 
1952  const Decl *D = C.getLocationContextFor(&Path)->getDecl();
1953  PathDiagnosticLocation EntryLoc =
1954  PathDiagnosticLocation::createBegin(D, C.getSourceManager());
1955  if (FirstEdge->getStartLocation() != EntryLoc)
1956  return;
1957 
1958  Path.pop_front();
1959 }
1960 
1961 /// Populate executes lines with lines containing at least one diagnostics.
1962 static void updateExecutedLinesWithDiagnosticPieces(PathDiagnostic &PD) {
1963 
1964  PathPieces path = PD.path.flatten(/*ShouldFlattenMacros=*/true);
1965  FilesToLineNumsMap &ExecutedLines = PD.getExecutedLines();
1966 
1967  for (const auto &P : path) {
1968  FullSourceLoc Loc = P->getLocation().asLocation().getExpansionLoc();
1969  FileID FID = Loc.getFileID();
1970  unsigned LineNo = Loc.getLineNumber();
1971  assert(FID.isValid());
1972  ExecutedLines[FID].insert(LineNo);
1973  }
1974 }
1975 
1976 PathDiagnosticConstruct::PathDiagnosticConstruct(
1977  const PathDiagnosticConsumer *PDC, const ExplodedNode *ErrorNode,
1978  const PathSensitiveBugReport *R)
1979  : Consumer(PDC), CurrentNode(ErrorNode),
1980  SM(CurrentNode->getCodeDecl().getASTContext().getSourceManager()),
1981  PD(generateEmptyDiagnosticForReport(R, getSourceManager())) {
1982  LCM[&PD->getActivePath()] = ErrorNode->getLocationContext();
1983 }
1984 
1985 PathDiagnosticBuilder::PathDiagnosticBuilder(
1986  BugReporterContext BRC, std::unique_ptr<ExplodedGraph> BugPath,
1987  PathSensitiveBugReport *r, const ExplodedNode *ErrorNode,
1988  std::unique_ptr<VisitorsDiagnosticsTy> VisitorsDiagnostics)
1989  : BugReporterContext(BRC), BugPath(std::move(BugPath)), R(r),
1990  ErrorNode(ErrorNode),
1991  VisitorsDiagnostics(std::move(VisitorsDiagnostics)) {}
1992 
1993 std::unique_ptr<PathDiagnostic>
1994 PathDiagnosticBuilder::generate(const PathDiagnosticConsumer *PDC) const {
1995  PathDiagnosticConstruct Construct(PDC, ErrorNode, R);
1996 
1997  const SourceManager &SM = getSourceManager();
1998  const AnalyzerOptions &Opts = getAnalyzerOptions();
1999 
2000  if (!PDC->shouldGenerateDiagnostics())
2001  return generateEmptyDiagnosticForReport(R, getSourceManager());
2002 
2003  // Construct the final (warning) event for the bug report.
2004  auto EndNotes = VisitorsDiagnostics->find(ErrorNode);
2005  PathDiagnosticPieceRef LastPiece;
2006  if (EndNotes != VisitorsDiagnostics->end()) {
2007  assert(!EndNotes->second.empty());
2008  LastPiece = EndNotes->second[0];
2009  } else {
2010  LastPiece = BugReporterVisitor::getDefaultEndPath(*this, ErrorNode,
2011  *getBugReport());
2012  }
2013  Construct.PD->setEndOfPath(LastPiece);
2014 
2015  PathDiagnosticLocation PrevLoc = Construct.PD->getLocation();
2016  // From the error node to the root, ascend the bug path and construct the bug
2017  // report.
2018  while (Construct.ascendToPrevNode()) {
2019  generatePathDiagnosticsForNode(Construct, PrevLoc);
2020 
2021  auto VisitorNotes = VisitorsDiagnostics->find(Construct.getCurrentNode());
2022  if (VisitorNotes == VisitorsDiagnostics->end())
2023  continue;
2024 
2025  // This is a workaround due to inability to put shared PathDiagnosticPiece
2026  // into a FoldingSet.
2027  std::set<llvm::FoldingSetNodeID> DeduplicationSet;
2028 
2029  // Add pieces from custom visitors.
2030  for (const PathDiagnosticPieceRef &Note : VisitorNotes->second) {
2031  llvm::FoldingSetNodeID ID;
2032  Note->Profile(ID);
2033  if (!DeduplicationSet.insert(ID).second)
2034  continue;
2035 
2036  if (PDC->shouldAddPathEdges())
2037  addEdgeToPath(Construct.getActivePath(), PrevLoc, Note->getLocation());
2038  updateStackPiecesWithMessage(Note, Construct.CallStack);
2039  Construct.getActivePath().push_front(Note);
2040  }
2041  }
2042 
2043  if (PDC->shouldAddPathEdges()) {
2044  // Add an edge to the start of the function.
2045  // We'll prune it out later, but it helps make diagnostics more uniform.
2046  const StackFrameContext *CalleeLC =
2047  Construct.getLocationContextForActivePath()->getStackFrame();
2048  const Decl *D = CalleeLC->getDecl();
2049  addEdgeToPath(Construct.getActivePath(), PrevLoc,
2050  PathDiagnosticLocation::createBegin(D, SM));
2051  }
2052 
2053 
2054  // Finally, prune the diagnostic path of uninteresting stuff.
2055  if (!Construct.PD->path.empty()) {
2056  if (R->shouldPrunePath() && Opts.ShouldPrunePaths) {
2057  bool stillHasNotes =
2058  removeUnneededCalls(Construct, Construct.getMutablePieces(), R);
2059  assert(stillHasNotes);
2060  (void)stillHasNotes;
2061  }
2062 
2063  // Remove pop-up notes if needed.
2064  if (!Opts.ShouldAddPopUpNotes)
2065  removePopUpNotes(Construct.getMutablePieces());
2066 
2067  // Redirect all call pieces to have valid locations.
2068  adjustCallLocations(Construct.getMutablePieces());
2069  removePiecesWithInvalidLocations(Construct.getMutablePieces());
2070 
2071  if (PDC->shouldAddPathEdges()) {
2072 
2073  // Reduce the number of edges from a very conservative set
2074  // to an aesthetically pleasing subset that conveys the
2075  // necessary information.
2076  OptimizedCallsSet OCS;
2077  while (optimizeEdges(Construct, Construct.getMutablePieces(), OCS)) {
2078  }
2079 
2080  // Drop the very first function-entry edge. It's not really necessary
2081  // for top-level functions.
2082  dropFunctionEntryEdge(Construct, Construct.getMutablePieces());
2083  }
2084 
2085  // Remove messages that are basically the same, and edges that may not
2086  // make sense.
2087  // We have to do this after edge optimization in the Extensive mode.
2088  removeRedundantMsgs(Construct.getMutablePieces());
2089  removeEdgesToDefaultInitializers(Construct.getMutablePieces());
2090  }
2091 
2092  if (Opts.ShouldDisplayMacroExpansions)
2093  CompactMacroExpandedPieces(Construct.getMutablePieces(), SM);
2094 
2095  return std::move(Construct.PD);
2096 }
2097 
2098 //===----------------------------------------------------------------------===//
2099 // Methods for BugType and subclasses.
2100 //===----------------------------------------------------------------------===//
2101 
2102 void BugType::anchor() {}
2103 
2104 void BuiltinBug::anchor() {}
2105 
2106 //===----------------------------------------------------------------------===//
2107 // Methods for BugReport and subclasses.
2108 //===----------------------------------------------------------------------===//
2109 
2110 LLVM_ATTRIBUTE_USED static bool
2111 isDependency(const CheckerRegistryData &Registry, StringRef CheckerName) {
2112  for (const std::pair<StringRef, StringRef> &Pair : Registry.Dependencies) {
2113  if (Pair.second == CheckerName)
2114  return true;
2115  }
2116  return false;
2117 }
2118 
2119 LLVM_ATTRIBUTE_USED static bool isHidden(const CheckerRegistryData &Registry,
2120  StringRef CheckerName) {
2121  for (const CheckerInfo &Checker : Registry.Checkers) {
2122  if (Checker.FullName == CheckerName)
2123  return Checker.IsHidden;
2124  }
2125  llvm_unreachable(
2126  "Checker name not found in CheckerRegistry -- did you retrieve it "
2127  "correctly from CheckerManager::getCurrentCheckerName?");
2128 }
2129 
2130 PathSensitiveBugReport::PathSensitiveBugReport(
2131  const BugType &bt, StringRef shortDesc, StringRef desc,
2132  const ExplodedNode *errorNode, PathDiagnosticLocation LocationToUnique,
2133  const Decl *DeclToUnique)
2134  : BugReport(Kind::PathSensitive, bt, shortDesc, desc), ErrorNode(errorNode),
2135  ErrorNodeRange(getStmt() ? getStmt()->getSourceRange() : SourceRange()),
2136  UniqueingLocation(LocationToUnique), UniqueingDecl(DeclToUnique) {
2137  assert(!isDependency(ErrorNode->getState()
2138  ->getAnalysisManager()
2139  .getCheckerManager()
2140  ->getCheckerRegistryData(),
2141  bt.getCheckerName()) &&
2142  "Some checkers depend on this one! We don't allow dependency "
2143  "checkers to emit warnings, because checkers should depend on "
2144  "*modeling*, not *diagnostics*.");
2145 
2146  assert(
2147  (bt.getCheckerName().startswith("debug") ||
2149  ->getAnalysisManager()
2150  .getCheckerManager()
2151  ->getCheckerRegistryData(),
2152  bt.getCheckerName())) &&
2153  "Hidden checkers musn't emit diagnostics as they are by definition "
2154  "non-user facing!");
2155 }
2156 
2158  std::unique_ptr<BugReporterVisitor> visitor) {
2159  if (!visitor)
2160  return;
2161 
2162  llvm::FoldingSetNodeID ID;
2163  visitor->Profile(ID);
2164 
2165  void *InsertPos = nullptr;
2166  if (CallbacksSet.FindNodeOrInsertPos(ID, InsertPos)) {
2167  return;
2168  }
2169 
2170  Callbacks.push_back(std::move(visitor));
2171 }
2172 
2174  Callbacks.clear();
2175 }
2176 
2178  const ExplodedNode *N = getErrorNode();
2179  if (!N)
2180  return nullptr;
2181 
2182  const LocationContext *LC = N->getLocationContext();
2183  return LC->getStackFrame()->getDecl();
2184 }
2185 
2186 void BasicBugReport::Profile(llvm::FoldingSetNodeID& hash) const {
2187  hash.AddInteger(static_cast<int>(getKind()));
2188  hash.AddPointer(&BT);
2189  hash.AddString(Description);
2190  assert(Location.isValid());
2191  Location.Profile(hash);
2192 
2193  for (SourceRange range : Ranges) {
2194  if (!range.isValid())
2195  continue;
2196  hash.Add(range.getBegin());
2197  hash.Add(range.getEnd());
2198  }
2199 }
2200 
2201 void PathSensitiveBugReport::Profile(llvm::FoldingSetNodeID &hash) const {
2202  hash.AddInteger(static_cast<int>(getKind()));
2203  hash.AddPointer(&BT);
2204  hash.AddString(Description);
2206  if (UL.isValid()) {
2207  UL.Profile(hash);
2208  } else {
2209  // TODO: The statement may be null if the report was emitted before any
2210  // statements were executed. In particular, some checkers by design
2211  // occasionally emit their reports in empty functions (that have no
2212  // statements in their body). Do we profile correctly in this case?
2214  }
2215 
2216  for (SourceRange range : Ranges) {
2217  if (!range.isValid())
2218  continue;
2219  hash.Add(range.getBegin());
2220  hash.Add(range.getEnd());
2221  }
2222 }
2223 
2224 template <class T>
2226  llvm::DenseMap<T, bugreporter::TrackingKind> &InterestingnessMap, T Val,
2227  bugreporter::TrackingKind TKind) {
2228  auto Result = InterestingnessMap.insert({Val, TKind});
2229 
2230  if (Result.second)
2231  return;
2232 
2233  // Even if this symbol/region was already marked as interesting as a
2234  // condition, if we later mark it as interesting again but with
2235  // thorough tracking, overwrite it. Entities marked with thorough
2236  // interestiness are the most important (or most interesting, if you will),
2237  // and we wouldn't like to downplay their importance.
2238 
2239  switch (TKind) {
2241  Result.first->getSecond() = bugreporter::TrackingKind::Thorough;
2242  return;
2244  return;
2245  }
2246 
2247  llvm_unreachable(
2248  "BugReport::markInteresting currently can only handle 2 different "
2249  "tracking kinds! Please define what tracking kind should this entitiy"
2250  "have, if it was already marked as interesting with a different kind!");
2251 }
2252 
2254  bugreporter::TrackingKind TKind) {
2255  if (!sym)
2256  return;
2257 
2259 
2260  // FIXME: No tests exist for this code and it is questionable:
2261  // How to handle multiple metadata for the same region?
2262  if (const auto *meta = dyn_cast<SymbolMetadata>(sym))
2263  markInteresting(meta->getRegion(), TKind);
2264 }
2265 
2267  if (!sym)
2268  return;
2269  InterestingSymbols.erase(sym);
2270 
2271  // The metadata part of markInteresting is not reversed here.
2272  // Just making the same region not interesting is incorrect
2273  // in specific cases.
2274  if (const auto *meta = dyn_cast<SymbolMetadata>(sym))
2275  markNotInteresting(meta->getRegion());
2276 }
2277 
2279  bugreporter::TrackingKind TKind) {
2280  if (!R)
2281  return;
2282 
2283  R = R->getBaseRegion();
2285 
2286  if (const auto *SR = dyn_cast<SymbolicRegion>(R))
2287  markInteresting(SR->getSymbol(), TKind);
2288 }
2289 
2291  if (!R)
2292  return;
2293 
2294  R = R->getBaseRegion();
2295  InterestingRegions.erase(R);
2296 
2297  if (const auto *SR = dyn_cast<SymbolicRegion>(R))
2298  markNotInteresting(SR->getSymbol());
2299 }
2300 
2302  bugreporter::TrackingKind TKind) {
2303  markInteresting(V.getAsRegion(), TKind);
2304  markInteresting(V.getAsSymbol(), TKind);
2305 }
2306 
2308  if (!LC)
2309  return;
2310  InterestingLocationContexts.insert(LC);
2311 }
2312 
2315  auto RKind = getInterestingnessKind(V.getAsRegion());
2316  auto SKind = getInterestingnessKind(V.getAsSymbol());
2317  if (!RKind)
2318  return SKind;
2319  if (!SKind)
2320  return RKind;
2321 
2322  // If either is marked with throrough tracking, return that, we wouldn't like
2323  // to downplay a note's importance by 'only' mentioning it as a condition.
2324  switch(*RKind) {
2326  return RKind;
2328  return SKind;
2329  }
2330 
2331  llvm_unreachable(
2332  "BugReport::getInterestingnessKind currently can only handle 2 different "
2333  "tracking kinds! Please define what tracking kind should we return here "
2334  "when the kind of getAsRegion() and getAsSymbol() is different!");
2335  return None;
2336 }
2337 
2340  if (!sym)
2341  return None;
2342  // We don't currently consider metadata symbols to be interesting
2343  // even if we know their region is interesting. Is that correct behavior?
2344  auto It = InterestingSymbols.find(sym);
2345  if (It == InterestingSymbols.end())
2346  return None;
2347  return It->getSecond();
2348 }
2349 
2352  if (!R)
2353  return None;
2354 
2355  R = R->getBaseRegion();
2356  auto It = InterestingRegions.find(R);
2357  if (It != InterestingRegions.end())
2358  return It->getSecond();
2359 
2360  if (const auto *SR = dyn_cast<SymbolicRegion>(R))
2361  return getInterestingnessKind(SR->getSymbol());
2362  return None;
2363 }
2364 
2366  return getInterestingnessKind(V).hasValue();
2367 }
2368 
2370  return getInterestingnessKind(sym).hasValue();
2371 }
2372 
2374  return getInterestingnessKind(R).hasValue();
2375 }
2376 
2378  if (!LC)
2379  return false;
2380  return InterestingLocationContexts.count(LC);
2381 }
2382 
2384  if (!ErrorNode)
2385  return nullptr;
2386 
2387  ProgramPoint ProgP = ErrorNode->getLocation();
2388  const Stmt *S = nullptr;
2389 
2390  if (Optional<BlockEntrance> BE = ProgP.getAs<BlockEntrance>()) {
2391  CFGBlock &Exit = ProgP.getLocationContext()->getCFG()->getExit();
2392  if (BE->getBlock() == &Exit)
2394  }
2395  if (!S)
2397 
2398  return S;
2399 }
2400 
2403  // If no custom ranges, add the range of the statement corresponding to
2404  // the error node.
2405  if (Ranges.empty() && isa_and_nonnull<Expr>(getStmt()))
2406  return ErrorNodeRange;
2407 
2408  return Ranges;
2409 }
2410 
2413  assert(ErrorNode && "Cannot create a location with a null node.");
2414  const Stmt *S = ErrorNode->getStmtForDiagnostics();
2416  const LocationContext *LC = P.getLocationContext();
2417  SourceManager &SM =
2418  ErrorNode->getState()->getStateManager().getContext().getSourceManager();
2419 
2420  if (!S) {
2421  // If this is an implicit call, return the implicit call point location.
2422  if (Optional<PreImplicitCall> PIE = P.getAs<PreImplicitCall>())
2423  return PathDiagnosticLocation(PIE->getLocation(), SM);
2424  if (auto FE = P.getAs<FunctionExitPoint>()) {
2425  if (const ReturnStmt *RS = FE->getStmt())
2426  return PathDiagnosticLocation::createBegin(RS, SM, LC);
2427  }
2429  }
2430 
2431  if (S) {
2432  // For member expressions, return the location of the '.' or '->'.
2433  if (const auto *ME = dyn_cast<MemberExpr>(S))
2435 
2436  // For binary operators, return the location of the operator.
2437  if (const auto *B = dyn_cast<BinaryOperator>(S))
2439 
2440  if (P.getAs<PostStmtPurgeDeadSymbols>())
2441  return PathDiagnosticLocation::createEnd(S, SM, LC);
2442 
2443  if (S->getBeginLoc().isValid())
2444  return PathDiagnosticLocation(S, SM, LC);
2445 
2446  return PathDiagnosticLocation(
2448  }
2449 
2451  SM);
2452 }
2453 
2454 //===----------------------------------------------------------------------===//
2455 // Methods for BugReporter and subclasses.
2456 //===----------------------------------------------------------------------===//
2457 
2459  return Eng.getGraph();
2460 }
2461 
2463  return Eng.getStateManager();
2464 }
2465 
2468  // Make sure reports are flushed.
2469  assert(StrBugTypes.empty() &&
2470  "Destroying BugReporter before diagnostics are emitted!");
2471 
2472  // Free the bug reports we are tracking.
2473  for (const auto I : EQClassesVector)
2474  delete I;
2475 }
2476 
2478  // We need to flush reports in deterministic order to ensure the order
2479  // of the reports is consistent between runs.
2480  for (const auto EQ : EQClassesVector)
2481  FlushReport(*EQ);
2482 
2483  // BugReporter owns and deletes only BugTypes created implicitly through
2484  // EmitBasicReport.
2485  // FIXME: There are leaks from checkers that assume that the BugTypes they
2486  // create will be destroyed by the BugReporter.
2487  StrBugTypes.clear();
2488 }
2489 
2490 //===----------------------------------------------------------------------===//
2491 // PathDiagnostics generation.
2492 //===----------------------------------------------------------------------===//
2493 
2494 namespace {
2495 
2496 /// A wrapper around an ExplodedGraph that contains a single path from the root
2497 /// to the error node.
2498 class BugPathInfo {
2499 public:
2500  std::unique_ptr<ExplodedGraph> BugPath;
2501  PathSensitiveBugReport *Report;
2502  const ExplodedNode *ErrorNode;
2503 };
2504 
2505 /// A wrapper around an ExplodedGraph whose leafs are all error nodes. Can
2506 /// conveniently retrieve bug paths from a single error node to the root.
2507 class BugPathGetter {
2508  std::unique_ptr<ExplodedGraph> TrimmedGraph;
2509 
2510  using PriorityMapTy = llvm::DenseMap<const ExplodedNode *, unsigned>;
2511 
2512  /// Assign each node with its distance from the root.
2513  PriorityMapTy PriorityMap;
2514 
2515  /// Since the getErrorNode() or BugReport refers to the original ExplodedGraph,
2516  /// we need to pair it to the error node of the constructed trimmed graph.
2517  using ReportNewNodePair =
2518  std::pair<PathSensitiveBugReport *, const ExplodedNode *>;
2520 
2521  BugPathInfo CurrentBugPath;
2522 
2523  /// A helper class for sorting ExplodedNodes by priority.
2524  template <bool Descending>
2525  class PriorityCompare {
2526  const PriorityMapTy &PriorityMap;
2527 
2528  public:
2529  PriorityCompare(const PriorityMapTy &M) : PriorityMap(M) {}
2530 
2531  bool operator()(const ExplodedNode *LHS, const ExplodedNode *RHS) const {
2532  PriorityMapTy::const_iterator LI = PriorityMap.find(LHS);
2533  PriorityMapTy::const_iterator RI = PriorityMap.find(RHS);
2534  PriorityMapTy::const_iterator E = PriorityMap.end();
2535 
2536  if (LI == E)
2537  return Descending;
2538  if (RI == E)
2539  return !Descending;
2540 
2541  return Descending ? LI->second > RI->second
2542  : LI->second < RI->second;
2543  }
2544 
2545  bool operator()(const ReportNewNodePair &LHS,
2546  const ReportNewNodePair &RHS) const {
2547  return (*this)(LHS.second, RHS.second);
2548  }
2549  };
2550 
2551 public:
2552  BugPathGetter(const ExplodedGraph *OriginalGraph,
2554 
2555  BugPathInfo *getNextBugPath();
2556 };
2557 
2558 } // namespace
2559 
2560 BugPathGetter::BugPathGetter(const ExplodedGraph *OriginalGraph,
2561  ArrayRef<PathSensitiveBugReport *> &bugReports) {
2563  for (const auto I : bugReports) {
2564  assert(I->isValid() &&
2565  "We only allow BugReporterVisitors and BugReporter itself to "
2566  "invalidate reports!");
2567  Nodes.emplace_back(I->getErrorNode());
2568  }
2569 
2570  // The trimmed graph is created in the body of the constructor to ensure
2571  // that the DenseMaps have been initialized already.
2572  InterExplodedGraphMap ForwardMap;
2573  TrimmedGraph = OriginalGraph->trim(Nodes, &ForwardMap);
2574 
2575  // Find the (first) error node in the trimmed graph. We just need to consult
2576  // the node map which maps from nodes in the original graph to nodes
2577  // in the new graph.
2579 
2580  for (PathSensitiveBugReport *Report : bugReports) {
2581  const ExplodedNode *NewNode = ForwardMap.lookup(Report->getErrorNode());
2582  assert(NewNode &&
2583  "Failed to construct a trimmed graph that contains this error "
2584  "node!");
2585  ReportNodes.emplace_back(Report, NewNode);
2586  RemainingNodes.insert(NewNode);
2587  }
2588 
2589  assert(!RemainingNodes.empty() && "No error node found in the trimmed graph");
2590 
2591  // Perform a forward BFS to find all the shortest paths.
2592  std::queue<const ExplodedNode *> WS;
2593 
2594  assert(TrimmedGraph->num_roots() == 1);
2595  WS.push(*TrimmedGraph->roots_begin());
2596  unsigned Priority = 0;
2597 
2598  while (!WS.empty()) {
2599  const ExplodedNode *Node = WS.front();
2600  WS.pop();
2601 
2602  PriorityMapTy::iterator PriorityEntry;
2603  bool IsNew;
2604  std::tie(PriorityEntry, IsNew) = PriorityMap.insert({Node, Priority});
2605  ++Priority;
2606 
2607  if (!IsNew) {
2608  assert(PriorityEntry->second <= Priority);
2609  continue;
2610  }
2611 
2612  if (RemainingNodes.erase(Node))
2613  if (RemainingNodes.empty())
2614  break;
2615 
2616  for (const ExplodedNode *Succ : Node->succs())
2617  WS.push(Succ);
2618  }
2619 
2620  // Sort the error paths from longest to shortest.
2621  llvm::sort(ReportNodes, PriorityCompare<true>(PriorityMap));
2622 }
2623 
2624 BugPathInfo *BugPathGetter::getNextBugPath() {
2625  if (ReportNodes.empty())
2626  return nullptr;
2627 
2628  const ExplodedNode *OrigN;
2629  std::tie(CurrentBugPath.Report, OrigN) = ReportNodes.pop_back_val();
2630  assert(PriorityMap.find(OrigN) != PriorityMap.end() &&
2631  "error node not accessible from root");
2632 
2633  // Create a new graph with a single path. This is the graph that will be
2634  // returned to the caller.
2635  auto GNew = std::make_unique<ExplodedGraph>();
2636 
2637  // Now walk from the error node up the BFS path, always taking the
2638  // predeccessor with the lowest number.
2639  ExplodedNode *Succ = nullptr;
2640  while (true) {
2641  // Create the equivalent node in the new graph with the same state
2642  // and location.
2643  ExplodedNode *NewN = GNew->createUncachedNode(
2644  OrigN->getLocation(), OrigN->getState(),
2645  OrigN->getID(), OrigN->isSink());
2646 
2647  // Link up the new node with the previous node.
2648  if (Succ)
2649  Succ->addPredecessor(NewN, *GNew);
2650  else
2651  CurrentBugPath.ErrorNode = NewN;
2652 
2653  Succ = NewN;
2654 
2655  // Are we at the final node?
2656  if (OrigN->pred_empty()) {
2657  GNew->addRoot(NewN);
2658  break;
2659  }
2660 
2661  // Find the next predeccessor node. We choose the node that is marked
2662  // with the lowest BFS number.
2663  OrigN = *std::min_element(OrigN->pred_begin(), OrigN->pred_end(),
2664  PriorityCompare<false>(PriorityMap));
2665  }
2666 
2667  CurrentBugPath.BugPath = std::move(GNew);
2668 
2669  return &CurrentBugPath;
2670 }
2671 
2672 /// CompactMacroExpandedPieces - This function postprocesses a PathDiagnostic
2673 /// object and collapses PathDiagosticPieces that are expanded by macros.
2674 static void CompactMacroExpandedPieces(PathPieces &path,
2675  const SourceManager& SM) {
2676  using MacroStackTy = std::vector<
2677  std::pair<std::shared_ptr<PathDiagnosticMacroPiece>, SourceLocation>>;
2678 
2679  using PiecesTy = std::vector<PathDiagnosticPieceRef>;
2680 
2681  MacroStackTy MacroStack;
2682  PiecesTy Pieces;
2683 
2684  for (PathPieces::const_iterator I = path.begin(), E = path.end();
2685  I != E; ++I) {
2686  const auto &piece = *I;
2687 
2688  // Recursively compact calls.
2689  if (auto *call = dyn_cast<PathDiagnosticCallPiece>(&*piece)) {
2690  CompactMacroExpandedPieces(call->path, SM);
2691  }
2692 
2693  // Get the location of the PathDiagnosticPiece.
2694  const FullSourceLoc Loc = piece->getLocation().asLocation();
2695 
2696  // Determine the instantiation location, which is the location we group
2697  // related PathDiagnosticPieces.
2698  SourceLocation InstantiationLoc = Loc.isMacroID() ?
2699  SM.getExpansionLoc(Loc) :
2700  SourceLocation();
2701 
2702  if (Loc.isFileID()) {
2703  MacroStack.clear();
2704  Pieces.push_back(piece);
2705  continue;
2706  }
2707 
2708  assert(Loc.isMacroID());
2709 
2710  // Is the PathDiagnosticPiece within the same macro group?
2711  if (!MacroStack.empty() && InstantiationLoc == MacroStack.back().second) {
2712  MacroStack.back().first->subPieces.push_back(piece);
2713  continue;
2714  }
2715 
2716  // We aren't in the same group. Are we descending into a new macro
2717  // or are part of an old one?
2718  std::shared_ptr<PathDiagnosticMacroPiece> MacroGroup;
2719 
2720  SourceLocation ParentInstantiationLoc = InstantiationLoc.isMacroID() ?
2721  SM.getExpansionLoc(Loc) :
2722  SourceLocation();
2723 
2724  // Walk the entire macro stack.
2725  while (!MacroStack.empty()) {
2726  if (InstantiationLoc == MacroStack.back().second) {
2727  MacroGroup = MacroStack.back().first;
2728  break;
2729  }
2730 
2731  if (ParentInstantiationLoc == MacroStack.back().second) {
2732  MacroGroup = MacroStack.back().first;
2733  break;
2734  }
2735 
2736  MacroStack.pop_back();
2737  }
2738 
2739  if (!MacroGroup || ParentInstantiationLoc == MacroStack.back().second) {
2740  // Create a new macro group and add it to the stack.
2741  auto NewGroup = std::make_shared<PathDiagnosticMacroPiece>(
2742  PathDiagnosticLocation::createSingleLocation(piece->getLocation()));
2743 
2744  if (MacroGroup)
2745  MacroGroup->subPieces.push_back(NewGroup);
2746  else {
2747  assert(InstantiationLoc.isFileID());
2748  Pieces.push_back(NewGroup);
2749  }
2750 
2751  MacroGroup = NewGroup;
2752  MacroStack.push_back(std::make_pair(MacroGroup, InstantiationLoc));
2753  }
2754 
2755  // Finally, add the PathDiagnosticPiece to the group.
2756  MacroGroup->subPieces.push_back(piece);
2757  }
2758 
2759  // Now take the pieces and construct a new PathDiagnostic.
2760  path.clear();
2761 
2762  path.insert(path.end(), Pieces.begin(), Pieces.end());
2763 }
2764 
2765 /// Generate notes from all visitors.
2766 /// Notes associated with @c ErrorNode are generated using
2767 /// @c getEndPath, and the rest are generated with @c VisitNode.
2768 static std::unique_ptr<VisitorsDiagnosticsTy>
2769 generateVisitorsDiagnostics(PathSensitiveBugReport *R,
2770  const ExplodedNode *ErrorNode,
2771  BugReporterContext &BRC) {
2772  std::unique_ptr<VisitorsDiagnosticsTy> Notes =
2773  std::make_unique<VisitorsDiagnosticsTy>();
2775 
2776  // Run visitors on all nodes starting from the node *before* the last one.
2777  // The last node is reserved for notes generated with @c getEndPath.
2778  const ExplodedNode *NextNode = ErrorNode->getFirstPred();
2779  while (NextNode) {
2780 
2781  // At each iteration, move all visitors from report to visitor list. This is
2782  // important, because the Profile() functions of the visitors make sure that
2783  // a visitor isn't added multiple times for the same node, but it's fine
2784  // to add the a visitor with Profile() for different nodes (e.g. tracking
2785  // a region at different points of the symbolic execution).
2786  for (std::unique_ptr<BugReporterVisitor> &Visitor : R->visitors())
2787  visitors.push_back(std::move(Visitor));
2788 
2789  R->clearVisitors();
2790 
2791  const ExplodedNode *Pred = NextNode->getFirstPred();
2792  if (!Pred) {
2793  PathDiagnosticPieceRef LastPiece;
2794  for (auto &V : visitors) {
2795  V->finalizeVisitor(BRC, ErrorNode, *R);
2796 
2797  if (auto Piece = V->getEndPath(BRC, ErrorNode, *R)) {
2798  assert(!LastPiece &&
2799  "There can only be one final piece in a diagnostic.");
2800  assert(Piece->getKind() == PathDiagnosticPiece::Kind::Event &&
2801  "The final piece must contain a message!");
2802  LastPiece = std::move(Piece);
2803  (*Notes)[ErrorNode].push_back(LastPiece);
2804  }
2805  }
2806  break;
2807  }
2808 
2809  for (auto &V : visitors) {
2810  auto P = V->VisitNode(NextNode, BRC, *R);
2811  if (P)
2812  (*Notes)[NextNode].push_back(std::move(P));
2813  }
2814 
2815  if (!R->isValid())
2816  break;
2817 
2818  NextNode = Pred;
2819  }
2820 
2821  return Notes;
2822 }
2823 
2824 Optional<PathDiagnosticBuilder> PathDiagnosticBuilder::findValidReport(
2826  PathSensitiveBugReporter &Reporter) {
2827 
2828  BugPathGetter BugGraph(&Reporter.getGraph(), bugReports);
2829 
2830  while (BugPathInfo *BugPath = BugGraph.getNextBugPath()) {
2831  // Find the BugReport with the original location.
2832  PathSensitiveBugReport *R = BugPath->Report;
2833  assert(R && "No original report found for sliced graph.");
2834  assert(R->isValid() && "Report selected by trimmed graph marked invalid.");
2835  const ExplodedNode *ErrorNode = BugPath->ErrorNode;
2836 
2837  // Register refutation visitors first, if they mark the bug invalid no
2838  // further analysis is required
2839  R->addVisitor<LikelyFalsePositiveSuppressionBRVisitor>();
2840 
2841  // Register additional node visitors.
2842  R->addVisitor<NilReceiverBRVisitor>();
2843  R->addVisitor<ConditionBRVisitor>();
2844  R->addVisitor<TagVisitor>();
2845 
2846  BugReporterContext BRC(Reporter);
2847 
2848  // Run all visitors on a given graph, once.
2849  std::unique_ptr<VisitorsDiagnosticsTy> visitorNotes =
2850  generateVisitorsDiagnostics(R, ErrorNode, BRC);
2851 
2852  if (R->isValid()) {
2853  if (Reporter.getAnalyzerOptions().ShouldCrosscheckWithZ3) {
2854  // If crosscheck is enabled, remove all visitors, add the refutation
2855  // visitor and check again
2856  R->clearVisitors();
2857  R->addVisitor<FalsePositiveRefutationBRVisitor>();
2858 
2859  // We don't overwrite the notes inserted by other visitors because the
2860  // refutation manager does not add any new note to the path
2861  generateVisitorsDiagnostics(R, BugPath->ErrorNode, BRC);
2862  }
2863 
2864  // Check if the bug is still valid
2865  if (R->isValid())
2866  return PathDiagnosticBuilder(
2867  std::move(BRC), std::move(BugPath->BugPath), BugPath->Report,
2868  BugPath->ErrorNode, std::move(visitorNotes));
2869  }
2870  }
2871 
2872  return {};
2873 }
2874 
2875 std::unique_ptr<DiagnosticForConsumerMapTy>
2878  ArrayRef<PathSensitiveBugReport *> &bugReports) {
2879  assert(!bugReports.empty());
2880 
2881  auto Out = std::make_unique<DiagnosticForConsumerMapTy>();
2882 
2884  PathDiagnosticBuilder::findValidReport(bugReports, *this);
2885 
2886  if (PDB) {
2887  for (PathDiagnosticConsumer *PC : consumers) {
2888  if (std::unique_ptr<PathDiagnostic> PD = PDB->generate(PC)) {
2889  (*Out)[PC] = std::move(PD);
2890  }
2891  }
2892  }
2893 
2894  return Out;
2895 }
2896 
2897 void BugReporter::emitReport(std::unique_ptr<BugReport> R) {
2898  bool ValidSourceLoc = R->getLocation().isValid();
2899  assert(ValidSourceLoc);
2900  // If we mess up in a release build, we'd still prefer to just drop the bug
2901  // instead of trying to go on.
2902  if (!ValidSourceLoc)
2903  return;
2904 
2905  // Compute the bug report's hash to determine its equivalence class.
2906  llvm::FoldingSetNodeID ID;
2907  R->Profile(ID);
2908 
2909  // Lookup the equivance class. If there isn't one, create it.
2910  void *InsertPos;
2911  BugReportEquivClass* EQ = EQClasses.FindNodeOrInsertPos(ID, InsertPos);
2912 
2913  if (!EQ) {
2914  EQ = new BugReportEquivClass(std::move(R));
2915  EQClasses.InsertNode(EQ, InsertPos);
2916  EQClassesVector.push_back(EQ);
2917  } else
2918  EQ->AddReport(std::move(R));
2919 }
2920 
2921 void PathSensitiveBugReporter::emitReport(std::unique_ptr<BugReport> R) {
2922  if (auto PR = dyn_cast<PathSensitiveBugReport>(R.get()))
2923  if (const ExplodedNode *E = PR->getErrorNode()) {
2924  // An error node must either be a sink or have a tag, otherwise
2925  // it could get reclaimed before the path diagnostic is created.
2926  assert((E->isSink() || E->getLocation().getTag()) &&
2927  "Error node must either be a sink or have a tag");
2928 
2929  const AnalysisDeclContext *DeclCtx =
2930  E->getLocationContext()->getAnalysisDeclContext();
2931  // The source of autosynthesized body can be handcrafted AST or a model
2932  // file. The locations from handcrafted ASTs have no valid source
2933  // locations and have to be discarded. Locations from model files should
2934  // be preserved for processing and reporting.
2935  if (DeclCtx->isBodyAutosynthesized() &&
2937  return;
2938  }
2939 
2940  BugReporter::emitReport(std::move(R));
2941 }
2942 
2943 //===----------------------------------------------------------------------===//
2944 // Emitting reports in equivalence classes.
2945 //===----------------------------------------------------------------------===//
2946 
2947 namespace {
2948 
2949 struct FRIEC_WLItem {
2950  const ExplodedNode *N;
2952 
2953  FRIEC_WLItem(const ExplodedNode *n)
2954  : N(n), I(N->succ_begin()), E(N->succ_end()) {}
2955 };
2956 
2957 } // namespace
2958 
2959 BugReport *PathSensitiveBugReporter::findReportInEquivalenceClass(
2960  BugReportEquivClass &EQ, SmallVectorImpl<BugReport *> &bugReports) {
2961  // If we don't need to suppress any of the nodes because they are
2962  // post-dominated by a sink, simply add all the nodes in the equivalence class
2963  // to 'Nodes'. Any of the reports will serve as a "representative" report.
2964  assert(EQ.getReports().size() > 0);
2965  const BugType& BT = EQ.getReports()[0]->getBugType();
2966  if (!BT.isSuppressOnSink()) {
2967  BugReport *R = EQ.getReports()[0].get();
2968  for (auto &J : EQ.getReports()) {
2969  if (auto *PR = dyn_cast<PathSensitiveBugReport>(J.get())) {
2970  R = PR;
2971  bugReports.push_back(PR);
2972  }
2973  }
2974  return R;
2975  }
2976 
2977  // For bug reports that should be suppressed when all paths are post-dominated
2978  // by a sink node, iterate through the reports in the equivalence class
2979  // until we find one that isn't post-dominated (if one exists). We use a
2980  // DFS traversal of the ExplodedGraph to find a non-sink node. We could write
2981  // this as a recursive function, but we don't want to risk blowing out the
2982  // stack for very long paths.
2983  BugReport *exampleReport = nullptr;
2984 
2985  for (const auto &I: EQ.getReports()) {
2986  auto *R = dyn_cast<PathSensitiveBugReport>(I.get());
2987  if (!R)
2988  continue;
2989 
2990  const ExplodedNode *errorNode = R->getErrorNode();
2991  if (errorNode->isSink()) {
2992  llvm_unreachable(
2993  "BugType::isSuppressSink() should not be 'true' for sink end nodes");
2994  }
2995  // No successors? By definition this nodes isn't post-dominated by a sink.
2996  if (errorNode->succ_empty()) {
2997  bugReports.push_back(R);
2998  if (!exampleReport)
2999  exampleReport = R;
3000  continue;
3001  }
3002 
3003  // See if we are in a no-return CFG block. If so, treat this similarly
3004  // to being post-dominated by a sink. This works better when the analysis
3005  // is incomplete and we have never reached the no-return function call(s)
3006  // that we'd inevitably bump into on this path.
3007  if (const CFGBlock *ErrorB = errorNode->getCFGBlock())
3008  if (ErrorB->isInevitablySinking())
3009  continue;
3010 
3011  // At this point we know that 'N' is not a sink and it has at least one
3012  // successor. Use a DFS worklist to find a non-sink end-of-path node.
3013  using WLItem = FRIEC_WLItem;
3014  using DFSWorkList = SmallVector<WLItem, 10>;
3015 
3016  llvm::DenseMap<const ExplodedNode *, unsigned> Visited;
3017 
3018  DFSWorkList WL;
3019  WL.push_back(errorNode);
3020  Visited[errorNode] = 1;
3021 
3022  while (!WL.empty()) {
3023  WLItem &WI = WL.back();
3024  assert(!WI.N->succ_empty());
3025 
3026  for (; WI.I != WI.E; ++WI.I) {
3027  const ExplodedNode *Succ = *WI.I;
3028  // End-of-path node?
3029  if (Succ->succ_empty()) {
3030  // If we found an end-of-path node that is not a sink.
3031  if (!Succ->isSink()) {
3032  bugReports.push_back(R);
3033  if (!exampleReport)
3034  exampleReport = R;
3035  WL.clear();
3036  break;
3037  }
3038  // Found a sink? Continue on to the next successor.
3039  continue;
3040  }
3041  // Mark the successor as visited. If it hasn't been explored,
3042  // enqueue it to the DFS worklist.
3043  unsigned &mark = Visited[Succ];
3044  if (!mark) {
3045  mark = 1;
3046  WL.push_back(Succ);
3047  break;
3048  }
3049  }
3050 
3051  // The worklist may have been cleared at this point. First
3052  // check if it is empty before checking the last item.
3053  if (!WL.empty() && &WL.back() == &WI)
3054  WL.pop_back();
3055  }
3056  }
3057 
3058  // ExampleReport will be NULL if all the nodes in the equivalence class
3059  // were post-dominated by sinks.
3060  return exampleReport;
3061 }
3062 
3063 void BugReporter::FlushReport(BugReportEquivClass& EQ) {
3064  SmallVector<BugReport*, 10> bugReports;
3065  BugReport *report = findReportInEquivalenceClass(EQ, bugReports);
3066  if (!report)
3067  return;
3068 
3069  // See whether we need to silence the checker/package.
3070  for (const std::string &CheckerOrPackage :
3071  getAnalyzerOptions().SilencedCheckersAndPackages) {
3072  if (report->getBugType().getCheckerName().startswith(
3073  CheckerOrPackage))
3074  return;
3075  }
3076 
3078  std::unique_ptr<DiagnosticForConsumerMapTy> Diagnostics =
3079  generateDiagnosticForConsumerMap(report, Consumers, bugReports);
3080 
3081  for (auto &P : *Diagnostics) {
3082  PathDiagnosticConsumer *Consumer = P.first;
3083  std::unique_ptr<PathDiagnostic> &PD = P.second;
3084 
3085  // If the path is empty, generate a single step path with the location
3086  // of the issue.
3087  if (PD->path.empty()) {
3088  PathDiagnosticLocation L = report->getLocation();
3089  auto piece = std::make_unique<PathDiagnosticEventPiece>(
3090  L, report->getDescription());
3091  for (SourceRange Range : report->getRanges())
3092  piece->addRange(Range);
3093  PD->setEndOfPath(std::move(piece));
3094  }
3095 
3096  PathPieces &Pieces = PD->getMutablePieces();
3097  if (getAnalyzerOptions().ShouldDisplayNotesAsEvents) {
3098  // For path diagnostic consumers that don't support extra notes,
3099  // we may optionally convert those to path notes.
3100  for (auto I = report->getNotes().rbegin(),
3101  E = report->getNotes().rend(); I != E; ++I) {
3102  PathDiagnosticNotePiece *Piece = I->get();
3103  auto ConvertedPiece = std::make_shared<PathDiagnosticEventPiece>(
3104  Piece->getLocation(), Piece->getString());
3105  for (const auto &R: Piece->getRanges())
3106  ConvertedPiece->addRange(R);
3107 
3108  Pieces.push_front(std::move(ConvertedPiece));
3109  }
3110  } else {
3111  for (auto I = report->getNotes().rbegin(),
3112  E = report->getNotes().rend(); I != E; ++I)
3113  Pieces.push_front(*I);
3114  }
3115 
3116  for (const auto &I : report->getFixits())
3117  Pieces.back()->addFixit(I);
3118 
3120  Consumer->HandlePathDiagnostic(std::move(PD));
3121  }
3122 }
3123 
3124 /// Insert all lines participating in the function signature \p Signature
3125 /// into \p ExecutedLines.
3127  const Decl *Signature, const SourceManager &SM,
3128  FilesToLineNumsMap &ExecutedLines) {
3129  SourceRange SignatureSourceRange;
3130  const Stmt* Body = Signature->getBody();
3131  if (const auto FD = dyn_cast<FunctionDecl>(Signature)) {
3132  SignatureSourceRange = FD->getSourceRange();
3133  } else if (const auto OD = dyn_cast<ObjCMethodDecl>(Signature)) {
3134  SignatureSourceRange = OD->getSourceRange();
3135  } else {
3136  return;
3137  }
3138  SourceLocation Start = SignatureSourceRange.getBegin();
3139  SourceLocation End = Body ? Body->getSourceRange().getBegin()
3140  : SignatureSourceRange.getEnd();
3141  if (!Start.isValid() || !End.isValid())
3142  return;
3143  unsigned StartLine = SM.getExpansionLineNumber(Start);
3144  unsigned EndLine = SM.getExpansionLineNumber(End);
3145 
3146  FileID FID = SM.getFileID(SM.getExpansionLoc(Start));
3147  for (unsigned Line = StartLine; Line <= EndLine; Line++)
3148  ExecutedLines[FID].insert(Line);
3149 }
3150 
3152  const Stmt *S, const SourceManager &SM,
3153  FilesToLineNumsMap &ExecutedLines) {
3154  SourceLocation Loc = S->getSourceRange().getBegin();
3155  if (!Loc.isValid())
3156  return;
3157  SourceLocation ExpansionLoc = SM.getExpansionLoc(Loc);
3158  FileID FID = SM.getFileID(ExpansionLoc);
3159  unsigned LineNo = SM.getExpansionLineNumber(ExpansionLoc);
3160  ExecutedLines[FID].insert(LineNo);
3161 }
3162 
3163 /// \return all executed lines including function signatures on the path
3164 /// starting from \p N.
3165 static std::unique_ptr<FilesToLineNumsMap>
3166 findExecutedLines(const SourceManager &SM, const ExplodedNode *N) {
3167  auto ExecutedLines = std::make_unique<FilesToLineNumsMap>();
3168 
3169  while (N) {
3170  if (N->getFirstPred() == nullptr) {
3171  // First node: show signature of the entrance point.
3172  const Decl *D = N->getLocationContext()->getDecl();
3173  populateExecutedLinesWithFunctionSignature(D, SM, *ExecutedLines);
3174  } else if (auto CE = N->getLocationAs<CallEnter>()) {
3175  // Inlined function: show signature.
3176  const Decl* D = CE->getCalleeContext()->getDecl();
3177  populateExecutedLinesWithFunctionSignature(D, SM, *ExecutedLines);
3178  } else if (const Stmt *S = N->getStmtForDiagnostics()) {
3179  populateExecutedLinesWithStmt(S, SM, *ExecutedLines);
3180 
3181  // Show extra context for some parent kinds.
3182  const Stmt *P = N->getParentMap().getParent(S);
3183 
3184  // The path exploration can die before the node with the associated
3185  // return statement is generated, but we do want to show the whole
3186  // return.
3187  if (const auto *RS = dyn_cast_or_null<ReturnStmt>(P)) {
3188  populateExecutedLinesWithStmt(RS, SM, *ExecutedLines);
3189  P = N->getParentMap().getParent(RS);
3190  }
3191 
3192  if (isa_and_nonnull<SwitchCase, LabelStmt>(P))
3193  populateExecutedLinesWithStmt(P, SM, *ExecutedLines);
3194  }
3195 
3196  N = N->getFirstPred();
3197  }
3198  return ExecutedLines;
3199 }
3200 
3201 std::unique_ptr<DiagnosticForConsumerMapTy>
3203  BugReport *exampleReport, ArrayRef<PathDiagnosticConsumer *> consumers,
3204  ArrayRef<BugReport *> bugReports) {
3205  auto *basicReport = cast<BasicBugReport>(exampleReport);
3206  auto Out = std::make_unique<DiagnosticForConsumerMapTy>();
3207  for (auto *Consumer : consumers)
3208  (*Out)[Consumer] = generateDiagnosticForBasicReport(basicReport);
3209  return Out;
3210 }
3211 
3212 static PathDiagnosticCallPiece *
3213 getFirstStackedCallToHeaderFile(PathDiagnosticCallPiece *CP,
3214  const SourceManager &SMgr) {
3215  SourceLocation CallLoc = CP->callEnter.asLocation();
3216 
3217  // If the call is within a macro, don't do anything (for now).
3218  if (CallLoc.isMacroID())
3219  return nullptr;
3220 
3221  assert(AnalysisManager::isInCodeFile(CallLoc, SMgr) &&
3222  "The call piece should not be in a header file.");
3223 
3224  // Check if CP represents a path through a function outside of the main file.
3225  if (!AnalysisManager::isInCodeFile(CP->callEnterWithin.asLocation(), SMgr))
3226  return CP;
3227 
3228  const PathPieces &Path = CP->path;
3229  if (Path.empty())
3230  return nullptr;
3231 
3232  // Check if the last piece in the callee path is a call to a function outside
3233  // of the main file.
3234  if (auto *CPInner = dyn_cast<PathDiagnosticCallPiece>(Path.back().get()))
3235  return getFirstStackedCallToHeaderFile(CPInner, SMgr);
3236 
3237  // Otherwise, the last piece is in the main file.
3238  return nullptr;
3239 }
3240 
3241 static void resetDiagnosticLocationToMainFile(PathDiagnostic &PD) {
3242  if (PD.path.empty())
3243  return;
3244 
3245  PathDiagnosticPiece *LastP = PD.path.back().get();
3246  assert(LastP);
3247  const SourceManager &SMgr = LastP->getLocation().getManager();
3248 
3249  // We only need to check if the report ends inside headers, if the last piece
3250  // is a call piece.
3251  if (auto *CP = dyn_cast<PathDiagnosticCallPiece>(LastP)) {
3252  CP = getFirstStackedCallToHeaderFile(CP, SMgr);
3253  if (CP) {
3254  // Mark the piece.
3255  CP->setAsLastInMainSourceFile();
3256 
3257  // Update the path diagnostic message.
3258  const auto *ND = dyn_cast<NamedDecl>(CP->getCallee());
3259  if (ND) {
3260  SmallString<200> buf;
3261  llvm::raw_svector_ostream os(buf);
3262  os << " (within a call to '" << ND->getDeclName() << "')";
3263  PD.appendToDesc(os.str());
3264  }
3265 
3266  // Reset the report containing declaration and location.
3267  PD.setDeclWithIssue(CP->getCaller());
3268  PD.setLocation(CP->getLocation());
3269 
3270  return;
3271  }
3272  }
3273 }
3274 
3275 
3276 
3277 std::unique_ptr<DiagnosticForConsumerMapTy>
3278 PathSensitiveBugReporter::generateDiagnosticForConsumerMap(
3279  BugReport *exampleReport, ArrayRef<PathDiagnosticConsumer *> consumers,
3280  ArrayRef<BugReport *> bugReports) {
3281  std::vector<BasicBugReport *> BasicBugReports;
3282  std::vector<PathSensitiveBugReport *> PathSensitiveBugReports;
3283  if (isa<BasicBugReport>(exampleReport))
3284  return BugReporter::generateDiagnosticForConsumerMap(exampleReport,
3285  consumers, bugReports);
3286 
3287  // Generate the full path sensitive diagnostic, using the generation scheme
3288  // specified by the PathDiagnosticConsumer. Note that we have to generate
3289  // path diagnostics even for consumers which do not support paths, because
3290  // the BugReporterVisitors may mark this bug as a false positive.
3291  assert(!bugReports.empty());
3292  MaxBugClassSize.updateMax(bugReports.size());
3293 
3294  // Avoid copying the whole array because there may be a lot of reports.
3295  ArrayRef<PathSensitiveBugReport *> convertedArrayOfReports(
3296  reinterpret_cast<PathSensitiveBugReport *const *>(&*bugReports.begin()),
3297  reinterpret_cast<PathSensitiveBugReport *const *>(&*bugReports.end()));
3298  std::unique_ptr<DiagnosticForConsumerMapTy> Out = generatePathDiagnostics(
3299  consumers, convertedArrayOfReports);
3300 
3301  if (Out->empty())
3302  return Out;
3303 
3304  MaxValidBugClassSize.updateMax(bugReports.size());
3305 
3306  // Examine the report and see if the last piece is in a header. Reset the
3307  // report location to the last piece in the main source file.
3308  const AnalyzerOptions &Opts = getAnalyzerOptions();
3309  for (auto const &P : *Out)
3310  if (Opts.ShouldReportIssuesInMainSourceFile && !Opts.AnalyzeAll)
3312 
3313  return Out;
3314 }
3315 
3316 void BugReporter::EmitBasicReport(const Decl *DeclWithIssue,
3317  const CheckerBase *Checker, StringRef Name,
3318  StringRef Category, StringRef Str,
3319  PathDiagnosticLocation Loc,
3320  ArrayRef<SourceRange> Ranges,
3321  ArrayRef<FixItHint> Fixits) {
3322  EmitBasicReport(DeclWithIssue, Checker->getCheckerName(), Name, Category, Str,
3323  Loc, Ranges, Fixits);
3324 }
3325 
3326 void BugReporter::EmitBasicReport(const Decl *DeclWithIssue,
3327  CheckerNameRef CheckName,
3328  StringRef name, StringRef category,
3329  StringRef str, PathDiagnosticLocation Loc,
3330  ArrayRef<SourceRange> Ranges,
3331  ArrayRef<FixItHint> Fixits) {
3332  // 'BT' is owned by BugReporter.
3333  BugType *BT = getBugTypeForName(CheckName, name, category);
3334  auto R = std::make_unique<BasicBugReport>(*BT, str, Loc);
3335  R->setDeclWithIssue(DeclWithIssue);
3336  for (const auto &SR : Ranges)
3337  R->addRange(SR);
3338  for (const auto &FH : Fixits)
3339  R->addFixItHint(FH);
3340  emitReport(std::move(R));
3341 }
3342 
3343 BugType *BugReporter::getBugTypeForName(CheckerNameRef CheckName,
3344  StringRef name, StringRef category) {
3345  SmallString<136> fullDesc;
3346  llvm::raw_svector_ostream(fullDesc) << CheckName.getName() << ":" << name
3347  << ":" << category;
3348  std::unique_ptr<BugType> &BT = StrBugTypes[fullDesc];
3349  if (!BT)
3350  BT = std::make_unique<BugType>(CheckName, name, category);
3351  return BT.get();
3352 }
CompactMacroExpandedPieces
static void CompactMacroExpandedPieces(PathPieces &path, const SourceManager &SM)
CompactMacroExpandedPieces - This function postprocesses a PathDiagnostic object and collapses PathDi...
Definition: BugReporter.cpp:2674
clang::ento::PathDiagnosticPiece::Event
@ Event
Definition: PathDiagnostic.h:407
resetDiagnosticLocationToMainFile
static void resetDiagnosticLocationToMainFile(PathDiagnostic &PD)
Definition: BugReporter.cpp:3241
getFirstStackedCallToHeaderFile
static PathDiagnosticCallPiece * getFirstStackedCallToHeaderFile(PathDiagnosticCallPiece *CP, const SourceManager &SMgr)
Definition: BugReporter.cpp:3213
AnalyzerOptions.h
clang::Decl::getASTContext
ASTContext & getASTContext() const LLVM_READONLY
Definition: DeclBase.cpp:414
clang::ento::PathSensitiveBugReport::InterestingLocationContexts
llvm::SmallSet< const LocationContext *, 2 > InterestingLocationContexts
A set of location contexts that correspoind to call sites which should be considered "interesting".
Definition: BugReporter.h:325
clang::ento::ExprEngine::getStateManager
ProgramStateManager & getStateManager()
Definition: ExprEngine.h:415
clang::ento::PathSensitiveBugReport::addVisitor
void addVisitor(std::unique_ptr< BugReporterVisitor > visitor)
Add custom or predefined bug report visitors to this report.
Definition: BugReporter.cpp:2157
llvm
Definition: Dominators.h:30
isHidden
static LLVM_ATTRIBUTE_USED bool isHidden(const CheckerRegistryData &Registry, StringRef CheckerName)
Definition: BugReporter.cpp:2119
clang::ento::PathDiagnosticLocation
Definition: PathDiagnostic.h:197
clang::ento::ExplodedNode::getLocationContext
const LocationContext * getLocationContext() const
Definition: ExplodedGraph.h:146
clang::LocationContext
It wraps the AnalysisDeclContext to represent both the call stack with the help of StackFrameContext ...
Definition: AnalysisDeclContext.h:215
clang::CFGBlock::getLoopTarget
const Stmt * getLoopTarget() const
Definition: CFG.h:1067
clang::LocationContext::getStackFrame
const StackFrameContext * getStackFrame() const
Definition: AnalysisDeclContext.cpp:463
SVals.h
clang::FullSourceLoc
A SourceLocation and its associated SourceManager.
Definition: SourceLocation.h:370
clang::ento::BugReporterData
Definition: BugReporter.h:571
Nodes
BoundNodesTreeBuilder Nodes
Definition: ASTMatchFinder.cpp:82
clang::SourceRange
A trivial tuple used to represent a source range.
Definition: SourceLocation.h:212
removeRedundantMsgs
static void removeRedundantMsgs(PathPieces &path)
An optimization pass over PathPieces that removes redundant diagnostics generated by both ConditionBR...
Definition: BugReporter.cpp:374
string
string(SUBSTRING ${CMAKE_CURRENT_BINARY_DIR} 0 ${PATH_LIB_START} PATH_HEAD) string(SUBSTRING $
Definition: CMakeLists.txt:22
clang::WhileStmt
WhileStmt - This represents a 'while' stmt.
Definition: Stmt.h:2341
clang::AnalysisDeclContext::isBodyAutosynthesized
bool isBodyAutosynthesized() const
Definition: AnalysisDeclContext.cpp:131
clang::ento::BasicBugReport::Profile
void Profile(llvm::FoldingSetNodeID &hash) const override
Reports are uniqued to ensure that we do not emit multiple diagnostics for each bug.
Definition: BugReporter.cpp:2186
clang::ento::PathDiagnosticPieceRef
std::shared_ptr< PathDiagnosticPiece > PathDiagnosticPieceRef
Definition: PathDiagnostic.h:494
clang::ento::BugType::getCheckerName
StringRef getCheckerName() const
Definition: BugType.h:52
clang::CFGBlock::succ_size
unsigned succ_size() const
Definition: CFG.h:973
clang::CFGBlock::succ_begin
succ_iterator succ_begin()
Definition: CFG.h:955
AnalysisDeclContext.h
clang::ento::PathDiagnosticLocation::createEnd
static PathDiagnosticLocation createEnd(const Stmt *S, const SourceManager &SM, const LocationOrAnalysisDeclContext LAC)
Create a location for the end of the statement.
Definition: PathDiagnostic.cpp:594
llvm::SmallVector
Definition: LLVM.h:38
clang::SourceLocation
Encodes a location in the source.
Definition: SourceLocation.h:88
clang::ento::PathDiagnosticLocation::getValidSourceLocation
static SourceLocation getValidSourceLocation(const Stmt *S, LocationOrAnalysisDeclContext LAC, bool UseEndOfStatement=false)
Construct a source location that corresponds to either the beginning or the end of the given statemen...
Definition: PathDiagnostic.cpp:478
findExecutedLines
static std::unique_ptr< FilesToLineNumsMap > findExecutedLines(const SourceManager &SM, const ExplodedNode *N)
Definition: BugReporter.cpp:3166
clang::SourceRange::getBegin
SourceLocation getBegin() const
Definition: SourceLocation.h:221
clang::ento::PathSensitiveBugReport::ErrorNode
const ExplodedNode * ErrorNode
The ExplodedGraph node against which the report was thrown.
Definition: BugReporter.h:300
clang::Stmt::getSourceRange
SourceRange getSourceRange() const LLVM_READONLY
SourceLocation tokens are not useful in isolation - they are low level value objects created/interpre...
Definition: Stmt.cpp:324
AttributeLangSupport::C
@ C
Definition: SemaDeclAttr.cpp:54
clang::AnalysisDeclContext
AnalysisDeclContext contains the context data for the function, method or block under analysis.
Definition: AnalysisDeclContext.h:72
getStmtBeforeCond
static const Stmt * getStmtBeforeCond(const ParentMap &PM, const Stmt *Term, const ExplodedNode *N)
Definition: BugReporter.cpp:1033
clang::Decl::hasBody
virtual bool hasBody() const
Returns true if this Decl represents a declaration for a body of code, such as a function or method d...
Definition: DeclBase.h:1016
clang::ento::ExplodedNode
Definition: ExplodedGraph.h:65
isInLoopBody
static bool isInLoopBody(const ParentMap &PM, const Stmt *S, const Stmt *Term)
Definition: BugReporter.cpp:1047
updateExecutedLinesWithDiagnosticPieces
static void updateExecutedLinesWithDiagnosticPieces(PathDiagnostic &PD)
Populate executes lines with lines containing at least one diagnostics.
Definition: BugReporter.cpp:1962
clang::ento::PathDiagnosticLocation::createSingleLocation
static PathDiagnosticLocation createSingleLocation(const PathDiagnosticLocation &PDL)
Convert the given location into a single kind location.
Definition: PathDiagnostic.cpp:736
SymbolManager.h
clang::ento::ConditionBRVisitor::getTag
static const char * getTag()
Return the tag associated with this visitor.
Definition: BugReporterVisitors.cpp:2547
adjustCallLocations
static void adjustCallLocations(PathPieces &Pieces, PathDiagnosticLocation *LastCallLocation=nullptr)
Recursively scan through a path and make sure that all call pieces have valid locations.
Definition: BugReporter.cpp:496
clang::IfStmt
IfStmt - This represents an if/then/else.
Definition: Stmt.h:1904
clang::ento::PathDiagnosticLocation::createMemberLoc
static PathDiagnosticLocation createMemberLoc(const MemberExpr *ME, const SourceManager &SM)
For member expressions, return the location of the '.
Definition: PathDiagnostic.cpp:617
clang::ento::SymbolRef
const SymExpr * SymbolRef
Definition: SymExpr.h:110
clang::CallExitEnd::getCalleeContext
const StackFrameContext * getCalleeContext() const
Definition: ProgramPoint.h:695
clang::ento::StackHintGeneratorForSymbol::getMessage
std::string getMessage(const ExplodedNode *N) override
Search the call expression for the symbol Sym and dispatch the 'getMessageForX()' methods to construc...
Definition: BugReporter.cpp:286
llvm::Optional
Definition: LLVM.h:40
clang::ento::bugreporter::TrackingKind
TrackingKind
Specifies the type of tracking for an expression.
Definition: BugReporterVisitors.h:95
llvm::SmallPtrSet
Definition: ASTContext.h:82
clang::StackFrameContext
It represents a stack frame of the call stack (based on CallEvent).
Definition: AnalysisDeclContext.h:295
SourceManager.h
removeIdenticalEvents
static void removeIdenticalEvents(PathPieces &path)
Definition: BugReporter.cpp:1740
clang::ento::PathSensitiveBugReport::getStmt
const Stmt * getStmt() const
Definition: BugReporter.cpp:2383
clang::serialized_diags::Note
@ Note
Definition: SerializedDiagnostics.h:45
clang::tooling::X
static ToolExecutorPluginRegistry::Add< AllTUsToolExecutorPlugin > X("all-TUs", "Runs FrontendActions on all TUs in the compilation database. " "Tool results are stored in memory.")
clang::ento::PathSensitiveBugReport::InterestingSymbols
llvm::DenseMap< SymbolRef, bugreporter::TrackingKind > InterestingSymbols
Profile to identify equivalent bug reports for error report coalescing.
Definition: BugReporter.h:313
clang::ObjCForCollectionStmt
Represents Objective-C's collection statement.
Definition: StmtObjC.h:23
clang::index::SymbolRole::Call
@ Call
removePiecesWithInvalidLocations
static void removePiecesWithInvalidLocations(PathPieces &Pieces)
Remove all pieces with invalid locations as these cannot be serialized.
Definition: BugReporter.cpp:563
clang::interp::EQ
bool EQ(InterpState &S, CodePtr OpPC)
Definition: Interp.h:218
isConditionForTerminator
static bool isConditionForTerminator(const Stmt *S, const Stmt *Cond)
Definition: BugReporter.cpp:1365
clang::tooling::fixit::internal::getSourceRange
CharSourceRange getSourceRange(const SourceRange &Range)
Returns the token CharSourceRange corresponding to Range.
Definition: FixIt.h:32
clang::ento::loc::MemRegionVal
Definition: SVals.h:606
End
SourceLocation End
Definition: USRLocFinder.cpp:167
getEnclosingStmtLocation
static PathDiagnosticLocation getEnclosingStmtLocation(const Stmt *S, const LocationContext *LC, bool allowNestedContexts=false)
Definition: BugReporter.cpp:642
clang::ASTContext::getSourceManager
SourceManager & getSourceManager()
Definition: ASTContext.h:695
clang::ento::BugReport::BT
const BugType & BT
Definition: BugReporter.h:130
clang::ento::BugReporter::FlushReports
void FlushReports()
Generate and flush diagnostics for all bug reports.
Definition: BugReporter.cpp:2477
clang::ProgramPoint::getLocationContext
const LocationContext * getLocationContext() const
Definition: ProgramPoint.h:179
isJumpToFalseBranch
static bool isJumpToFalseBranch(const BlockEdge *BE)
Definition: BugReporter.cpp:1017
clang::ento::PathSensitiveBugReport::getUniqueingLocation
PathDiagnosticLocation getUniqueingLocation() const override
Get the location on which the report should be uniqued.
Definition: BugReporter.h:414
clang::SourceManager
This class handles loading and caching of source files into memory.
Definition: SourceManager.h:626
getLengthOnSingleLine
static Optional< size_t > getLengthOnSingleLine(const SourceManager &SM, SourceRange Range)
Returns the number of bytes in the given (character-based) SourceRange.
Definition: BugReporter.cpp:1572
clang::ento::SVal::getAs
Optional< T > getAs() const
Convert to the specified SVal type, returning None if this SVal is not of the desired type.
Definition: SVals.h:111
macro
macro(clang_diag_gen component) clang_tablegen(Diagnostic$
Definition: CMakeLists.txt:1
Decl.h
DeclObjC.h
clang::ento::MemRegion
MemRegion - The root abstract class for all memory regions.
Definition: MemRegion.h:94
clang::BlockEdge::getSrc
const CFGBlock * getSrc() const
Definition: ProgramPoint.h:511
clang::CFGBlock
Represents a single basic block in a source-level CFG.
Definition: CFG.h:576
clang::ento::PathDiagnosticPiece::Call
@ Call
Definition: PathDiagnostic.h:407
clang::ento::SVal::getAsLocSymbol
SymbolRef getAsLocSymbol(bool IncludeBaseRegions=false) const
If this SVal is a location and wraps a symbol, return that SymbolRef.
Definition: SVals.cpp:87
clang::ento::TrackConstraintBRVisitor::getTag
static const char * getTag()
Return the tag associated with this visitor.
Definition: BugReporterVisitors.cpp:1644
V
#define V(N, I)
Definition: ASTContext.h:3121
clang::ento::ExplodedNode::getState
const ProgramStateRef & getState() const
Definition: ExplodedGraph.h:169
ProgramPoint.h
clang::ento::BugReport::Ranges
SmallVector< SourceRange, 4 > Ranges
Definition: BugReporter.h:134
insertToInterestingnessMap
static void insertToInterestingnessMap(llvm::DenseMap< T, bugreporter::TrackingKind > &InterestingnessMap, T Val, bugreporter::TrackingKind TKind)
Definition: BugReporter.cpp:2225
clang::ento::BugReporter::~BugReporter
virtual ~BugReporter()
Definition: BugReporter.cpp:2467
clang::AnalysisDeclContext::isBodyAutosynthesizedFromModelFile
bool isBodyAutosynthesizedFromModelFile() const
Definition: AnalysisDeclContext.cpp:137
clang::ento::AnalysisManager::isInCodeFile
static bool isInCodeFile(SourceLocation SL, const SourceManager &SM)
Definition: AnalysisManager.h:125
clang::StmtPoint
Definition: ProgramPoint.h:271
Node
DynTypedNode Node
Definition: ASTMatchFinder.cpp:67
lexicalContains
static bool lexicalContains(const ParentMap &PM, const Stmt *X, const Stmt *Y)
Return true if X is contained by Y.
Definition: BugReporter.cpp:1677
DeclBase.h
clang::ento::StackHintGenerator::~StackHintGenerator
virtual ~StackHintGenerator()=0
clang::ento::BugReporter::emitReport
virtual void emitReport(std::unique_ptr< BugReport > R)
Add the given report to the set of reports tracked by BugReporter.
Definition: BugReporter.cpp:2897
clang::SourceRange::getEnd
SourceLocation getEnd() const
Definition: SourceLocation.h:222
CheckerManager.h
isDependency
static LLVM_ATTRIBUTE_USED bool isDependency(const CheckerRegistryData &Registry, StringRef CheckerName)
Definition: BugReporter.cpp:2111
BugReporter.h
clang::ento::BugReporter::getPathDiagnosticConsumers
ArrayRef< PathDiagnosticConsumer * > getPathDiagnosticConsumers()
Definition: BugReporter.h:607
clang::PostStmtPurgeDeadSymbols
Represents a point after we ran remove dead bindings AFTER processing the given statement.
Definition: ProgramPoint.h:489
clang::Stmt::CastIterator
Iterator for iterating over Stmt * arrays that contain only T *.
Definition: Stmt.h:1119
clang::ProgramPoint::getAs
Optional< T > getAs() const
Convert to the specified ProgramPoint type, returning None if this ProgramPoint is not of the desired...
Definition: ProgramPoint.h:151
clang::FileID::isValid
bool isValid() const
Definition: SourceLocation.h:46
clang::ento::SymExpr
Symbolic value.
Definition: SymExpr.h:29
clang::ento::PathDiagnosticLocation::isValid
bool isValid() const
Definition: PathDiagnostic.h:337
clang::CallExitEnd
Represents a point when we finish the call exit sequence (for inlined call).
Definition: ProgramPoint.h:688
clang::ento::PathSensitiveBugReport::getErrorNode
const ExplodedNode * getErrorNode() const
Definition: BugReporter.h:404
clang::ento::BugType
Definition: BugType.h:29
clang::ento::bugreporter::TrackingKind::Condition
@ Condition
Specifies that a more moderate tracking should be used for the expression value.
SMTConv.h
clang::FunctionExitPoint
Definition: ProgramPoint.h:335
clang::ForStmt
ForStmt - This represents a 'for (init;cond;inc)' stmt.
Definition: Stmt.h:2534
clang::ento::PathDiagnosticLocation::createOperatorLoc
static PathDiagnosticLocation createOperatorLoc(const BinaryOperator *BO, const SourceManager &SM)
Create the location for the operator of the binary expression.
Definition: PathDiagnostic.cpp:604
clang::ento::BugReporter::getAnalyzerOptions
const AnalyzerOptions & getAnalyzerOptions()
Definition: BugReporter.h:620
clang::isa
bool isa(CodeGen::Address addr)
Definition: Address.h:111
Expr.h
llvm::SmallString
Definition: LLVM.h:37
clang::ento::ExplodedNode::getPreviousStmtForDiagnostics
const Stmt * getPreviousStmtForDiagnostics() const
Find the statement that was executed immediately before this node.
Definition: ExplodedGraph.cpp:378
clang::ento::BugReporterVisitor::~BugReporterVisitor
virtual ~BugReporterVisitor()
clang::ento::BugReporter::generateDiagnosticForConsumerMap
virtual std::unique_ptr< DiagnosticForConsumerMapTy > generateDiagnosticForConsumerMap(BugReport *exampleReport, ArrayRef< PathDiagnosticConsumer * > consumers, ArrayRef< BugReport * > bugReports)
Generate the diagnostics for the given bug report.
Definition: BugReporter.cpp:3202
clang::ento::BugReportEquivClass
Definition: BugReporter.h:546
clang::ento::PathDiagnosticConsumer
Definition: PathDiagnostic.h:94
clang::ento::PathSensitiveBugReport::VisitorList
SmallVector< std::unique_ptr< BugReporterVisitor >, 8 > VisitorList
Definition: BugReporter.h:293
clang::ento::bugreporter::TrackingKind::Thorough
@ Thorough
Default tracking kind – specifies that as much information should be gathered about the tracked expre...
clang::ento::FilesToLineNumsMap
std::map< FileID, std::set< unsigned > > FilesToLineNumsMap
File IDs mapped to sets of line numbers.
Definition: PathDiagnostic.h:762
populateExecutedLinesWithStmt
static void populateExecutedLinesWithStmt(const Stmt *S, const SourceManager &SM, FilesToLineNumsMap &ExecutedLines)
Definition: BugReporter.cpp:3151
clang::SourceLocation::isFileID
bool isFileID() const
Definition: SourceLocation.h:104
llvm::DenseSet
Definition: Sema.h:78
clang::Expr::EvaluateKnownConstInt
llvm::APSInt EvaluateKnownConstInt(const ASTContext &Ctx, SmallVectorImpl< PartialDiagnosticAt > *Diag=nullptr) const
EvaluateKnownConstInt - Call EvaluateAsRValue and return the folded integer.
Definition: ExprConstant.cpp:14958
clang::BlockEdge::getDst
const CFGBlock * getDst() const
Definition: ProgramPoint.h:515
PathDiagnostic.h
clang::ento::PathDiagnosticLocation::createDeclEnd
static PathDiagnosticLocation createDeclEnd(const LocationContext *LC, const SourceManager &SM)
Constructs a location for the end of the enclosing declaration body.
Definition: PathDiagnostic.cpp:658
clang::ento::BugReport::getKind
Kind getKind() const
Definition: BugReporter.h:149
ExprCXX.h
clang::CFGBlock::getTerminatorCondition
Stmt * getTerminatorCondition(bool StripParens=true)
Definition: CFG.cpp:5992
STATISTIC
STATISTIC(MaxBugClassSize, "The maximum number of bug reports in the same equivalence class")
StrLoopCollectionEmpty
constexpr llvm::StringLiteral StrLoopCollectionEmpty
Definition: BugReporter.cpp:1119
clang::ento::PathDiagnosticCallPiece
Definition: PathDiagnostic.h:566
clang::CFG::getExit
CFGBlock & getExit()
Definition: CFG.h:1333
clang::ento::ExplodedGraph
Definition: ExplodedGraph.h:304
Line
const AnnotatedLine * Line
Definition: UsingDeclarationsSorter.cpp:68
ExplodedGraph.h
clang::Decl::isImplicit
bool isImplicit() const
isImplicit - Indicates whether the declaration was implicitly generated by the implementation.
Definition: DeclBase.h:563
clang::ento::PathDiagnosticPiece::PopUp
@ PopUp
Definition: PathDiagnostic.h:407
StmtObjC.h
clang::ento::PathSensitiveBugReport::CallbacksSet
llvm::FoldingSet< BugReporterVisitor > CallbacksSet
Used for ensuring the visitors are only added once.
Definition: BugReporter.h:332
CFGStmtMap.h
CheckerRegistryData.h
dropFunctionEntryEdge
static void dropFunctionEntryEdge(const PathDiagnosticConstruct &C, PathPieces &Path)
Drop the very first edge in a path, which should be a function entry edge.
Definition: BugReporter.cpp:1945
clang::ento::PathDiagnosticLocation::Profile
void Profile(llvm::FoldingSetNodeID &ID) const
Definition: PathDiagnostic.cpp:1085
generateEmptyDiagnosticForReport
static std::unique_ptr< PathDiagnostic > generateEmptyDiagnosticForReport(const PathSensitiveBugReport *R, const SourceManager &SM)
Definition: BugReporter.cpp:1336
removeContextCycles
static void removeContextCycles(PathPieces &Path, const SourceManager &SM)
Eliminate two-edge cycles created by addContextEdges().
Definition: BugReporter.cpp:1622
isIncrementOrInitInForLoop
static bool isIncrementOrInitInForLoop(const Stmt *S, const Stmt *FL)
Definition: BugReporter.cpp:1406
clang::BlockEntrance
Definition: ProgramPoint.h:225
clang::Expr::IgnoreParenCasts
Expr * IgnoreParenCasts() LLVM_READONLY
Skip past any parentheses and casts which might surround this expression until reaching a fixed point...
Definition: Expr.cpp:2924
clang::ParentMap
Definition: ParentMap.h:20
clang::PostStmt
Definition: ProgramPoint.h:311
clang::ento::PathSensitiveBugReport::getDeclWithIssue
const Decl * getDeclWithIssue() const override
The smallest declaration that contains the bug location.
Definition: BugReporter.cpp:2177
SourceLocation.h
removePopUpNotes
static void removePopUpNotes(PathPieces &Path)
Same logic as above to remove extra pieces.
Definition: BugReporter.cpp:477
P
StringRef P
Definition: ASTMatchersInternal.cpp:563
clang::ento::PathSensitiveBugReporter::emitReport
void emitReport(std::unique_ptr< BugReport > R) override
Add the given report to the set of reports tracked by BugReporter.
Definition: BugReporter.cpp:2921
clang::ento::PathSensitiveBugReporter::getGraph
const ExplodedGraph & getGraph() const
getGraph - Get the exploded graph created by the analysis engine for the analyzed method or function.
Definition: BugReporter.cpp:2458
removePunyEdges
static void removePunyEdges(PathPieces &path, const SourceManager &SM, const ParentMap &PM)
Definition: BugReporter.cpp:1687
clang::Stmt::getStmtClass
StmtClass getStmtClass() const
Definition: Stmt.h:1163
clang::ento::BugReport::Description
std::string Description
Definition: BugReporter.h:132
clang::ento::PathSensitiveBugReport::getRanges
ArrayRef< SourceRange > getRanges() const override
Get the SourceRanges associated with the report.
Definition: BugReporter.cpp:2402
clang::ento::ProgramStateManager
Definition: ProgramState.h:463
populateExecutedLinesWithFunctionSignature
static void populateExecutedLinesWithFunctionSignature(const Decl *Signature, const SourceManager &SM, FilesToLineNumsMap &ExecutedLines)
Insert all lines participating in the function signature Signature into ExecutedLines.
Definition: BugReporter.cpp:3126
BugType.h
clang::ento::BugReporter::EmitBasicReport
void EmitBasicReport(const Decl *DeclWithIssue, const CheckerBase *Checker, StringRef BugName, StringRef BugCategory, StringRef BugStr, PathDiagnosticLocation Loc, ArrayRef< SourceRange > Ranges=None, ArrayRef< FixItHint > Fixits=None)
clang::ento::ConditionBRVisitor::isPieceMessageGeneric
static bool isPieceMessageGeneric(const PathDiagnosticPiece *Piece)
Definition: BugReporterVisitors.cpp:3074
clang::ento::ExplodedNode::const_succ_iterator
const ExplodedNode *const * const_succ_iterator
Definition: ExplodedGraph.h:230
clang::ento::PathSensitiveBugReport::InterestingRegions
llvm::DenseMap< const MemRegion *, bugreporter::TrackingKind > InterestingRegions
A (stack of) set of regions that are registered with this report as being "interesting",...
Definition: BugReporter.h:321
StrLoopRangeEmpty
constexpr llvm::StringLiteral StrLoopRangeEmpty
Definition: BugReporter.cpp:1117
hasImplicitBody
static bool hasImplicitBody(const Decl *D)
Returns true if the given decl has been implicitly given a body, either by the analyzer or by the com...
Definition: BugReporter.cpp:488
eventsDescribeSameCondition
static PathDiagnosticEventPiece * eventsDescribeSameCondition(PathDiagnosticEventPiece *X, PathDiagnosticEventPiece *Y)
Definition: BugReporter.cpp:348
clang::ento::ExplodedNode::getNextStmtForDiagnostics
const Stmt * getNextStmtForDiagnostics() const
Find the next statement that was executed on this node's execution path.
Definition: ExplodedGraph.cpp:351
clang::CFGBlock::getLabel
Stmt * getLabel()
Definition: CFG.h:1069
llvm::ArrayRef
Definition: LLVM.h:34
clang::Decl
Decl - This represents one declaration (or definition), e.g.
Definition: DeclBase.h:89
clang::ento::PathSensitiveBugReport::Callbacks
VisitorList Callbacks
A set of custom visitors which generate "event" diagnostics at interesting points in the path.
Definition: BugReporter.h:329
simplifySimpleBranches
static void simplifySimpleBranches(PathPieces &pieces)
Move edges from a branch condition to a branch target when the condition is simple.
Definition: BugReporter.cpp:1503
StrLoopBodyZero
constexpr llvm::StringLiteral StrLoopBodyZero
Definition: BugReporter.cpp:1116
BugReporterVisitors.h
clang::StackFrameContext::getCallSite
const Stmt * getCallSite() const
Definition: AnalysisDeclContext.h:321
addContextEdges
static void addContextEdges(PathPieces &pieces, const LocationContext *LC)
Adds synthetic edges from top-level statements to their subexpressions.
Definition: BugReporter.cpp:1422
clang::PreImplicitCall
Represents a program point just before an implicit call event.
Definition: ProgramPoint.h:583
clang::ento::PathSensitiveBugReporter::getStateManager
ProgramStateManager & getStateManager() const
getStateManager - Return the state manager used by the analysis engine.
Definition: BugReporter.cpp:2462
LLVM.h
clang::AnalyzerOptions
Stores options for the analyzer from the command line.
Definition: AnalyzerOptions.h:163
addEdgeToPath
static void addEdgeToPath(PathPieces &path, PathDiagnosticLocation &PrevLoc, PathDiagnosticLocation NewLoc)
Adds a sanitized control-flow diagnostic edge to a path.
Definition: BugReporter.cpp:1081
generateDiagnosticForBasicReport
static std::unique_ptr< PathDiagnostic > generateDiagnosticForBasicReport(const BasicBugReport *R)
Definition: BugReporter.cpp:1326
clang::ento::BugReporter::BugReporter
BugReporter(BugReporterData &d)
Definition: BugReporter.cpp:2466
clang::ParentMap::getParent
Stmt * getParent(Stmt *) const
Definition: ParentMap.cpp:134
generateVisitorsDiagnostics
static std::unique_ptr< VisitorsDiagnosticsTy > generateVisitorsDiagnostics(PathSensitiveBugReport *R, const ExplodedNode *ErrorNode, BugReporterContext &BRC)
Generate notes from all visitors.
Definition: BugReporter.cpp:2769
clang::ento::PathDiagnosticLocation::createEndBrace
static PathDiagnosticLocation createEndBrace(const CompoundStmt *CS, const SourceManager &SM)
Create a location for the end of the compound statement.
Definition: PathDiagnostic.cpp:638
getEnclosingParent
static const Stmt * getEnclosingParent(const Stmt *S, const ParentMap &PM)
Definition: BugReporter.cpp:619
clang::FullSourceLoc::getFileID
FileID getFileID() const
Definition: SourceLocation.cpp:159
getTerminatorCondition
static const Stmt * getTerminatorCondition(const CFGBlock *B)
A customized wrapper for CFGBlock::getTerminatorCondition() which returns the element for ObjCForColl...
Definition: BugReporter.cpp:1108
clang::ento::PathDiagnosticEventPiece
Definition: PathDiagnostic.h:536
Priority
int Priority
Definition: Format.cpp:2337
clang::SourceLocation::isMacroID
bool isMacroID() const
Definition: SourceLocation.h:105
clang::CXXForRangeStmt
CXXForRangeStmt - This represents C++0x [stmt.ranged]'s ranged for statement, represented as 'for (ra...
Definition: StmtCXX.h:134
ProgramState.h
StrEnteringLoop
constexpr llvm::StringLiteral StrEnteringLoop
Definition: BugReporter.cpp:1115
clang::Decl::getBody
virtual Stmt * getBody() const
getBody - If this Decl represents a declaration for a body of code, such as a function or method defi...
Definition: DeclBase.h:1010
clang::ento::BugReport::Kind
Kind
Definition: BugReporter.h:123
Checker.h
std
Definition: Format.h:4034
clang::ento::PathSensitiveBugReport
Definition: BugReporter.h:291
ExprEngine.h
clang::ento::PathSensitiveBugReport::markNotInteresting
void markNotInteresting(SymbolRef sym)
Definition: BugReporter.cpp:2266
ParentMap.h
clang::ento::BugReport
This class provides an interface through which checkers can create individual bug reports.
Definition: BugReporter.h:121
clang::Builtin::ID
ID
Definition: Builtins.h:48
clang::SourceLocation::isInvalid
bool isInvalid() const
Definition: SourceLocation.h:113
clang
Definition: CalledOnceCheck.h:17
clang::ento::PathDiagnosticPiece::Note
@ Note
Definition: PathDiagnostic.h:407
clang::ento::PathSensitiveBugReport::getInterestingnessKind
Optional< bugreporter::TrackingKind > getInterestingnessKind(SymbolRef sym) const
Definition: BugReporter.cpp:2339
clang::transformer::range
RangeSelector range(RangeSelector Begin, RangeSelector End)
DEPRECATED. Use enclose.
Definition: RangeSelector.h:41
clang::ento::ExplodedNode::getLocation
ProgramPoint getLocation() const
getLocation - Returns the edge associated with the given node.
Definition: ExplodedGraph.h:144
CFG.h
clang::Stmt
Stmt - This represents one statement.
Definition: Stmt.h:69
removeUnneededCalls
static bool removeUnneededCalls(const PathDiagnosticConstruct &C, PathPieces &pieces, const PathSensitiveBugReport *R, bool IsInteresting=false)
Recursively scan through a path and prune out calls and macros pieces that aren't needed.
Definition: BugReporter.cpp:424
clang::ento::PathDiagnosticPiece::Macro
@ Macro
Definition: PathDiagnostic.h:407
clang::CFGBlock::getTerminatorStmt
Stmt * getTerminatorStmt()
Definition: CFG.h:1050
clang::ento::PathSensitiveBugReport::ErrorNodeRange
const SourceRange ErrorNodeRange
The range that corresponds to ErrorNode's program point.
Definition: BugReporter.h:304
MemRegion.h
clang::FileID
An opaque identifier used by SourceManager which refers to a source file (MemoryBuffer) along with it...
Definition: SourceLocation.h:40
clang::SourceLocation::isValid
bool isValid() const
Return true if this is a valid SourceLocation object.
Definition: SourceLocation.h:112
clang::ParentMap::getParentIgnoreParens
Stmt * getParentIgnoreParens(Stmt *) const
Definition: ParentMap.cpp:140
clang::ento::PathDiagnosticLocation::createBegin
static PathDiagnosticLocation createBegin(const Decl *D, const SourceManager &SM)
Create a location for the beginning of the declaration.
Definition: PathDiagnostic.cpp:580
clang::ento::ExplodedNode::getSVal
SVal getSVal(const Stmt *S) const
Get the value of an arbitrary expression at this node.
Definition: ExplodedGraph.h:177
clang::ento::PathDiagnosticCallPiece::construct
static std::shared_ptr< PathDiagnosticCallPiece > construct(const CallExitEnd &CE, const SourceManager &SM)
Definition: PathDiagnostic.cpp:847
clang::ento::PathSensitiveBugReport::markInteresting
void markInteresting(SymbolRef sym, bugreporter::TrackingKind TKind=bugreporter::TrackingKind::Thorough)
Marks a symbol as interesting.
clang::Stmt::getBeginLoc
SourceLocation getBeginLoc() const LLVM_READONLY
Definition: Stmt.cpp:336
isContainedByStmt
static bool isContainedByStmt(const ParentMap &PM, const Stmt *S, const Stmt *SubS)
Definition: BugReporter.cpp:1023
clang::ento::PathSensitiveBugReport::Profile
void Profile(llvm::FoldingSetNodeID &hash) const override
Profile to identify equivalent bug reports for error report coalescing.
Definition: BugReporter.cpp:2201
clang::ento::PathSensitiveBugReporter::generatePathDiagnostics
std::unique_ptr< DiagnosticForConsumerMapTy > generatePathDiagnostics(ArrayRef< PathDiagnosticConsumer * > consumers, ArrayRef< PathSensitiveBugReport * > &bugReports)
bugReports A set of bug reports within a single equivalence class
Definition: BugReporter.cpp:2876
isLoop
static bool isLoop(const Stmt *Term)
Definition: BugReporter.cpp:1004
clang::ento::ExplodedNode::getStmtForDiagnostics
const Stmt * getStmtForDiagnostics() const
If the node's program point corresponds to a statement, retrieve that statement.
Definition: ExplodedGraph.cpp:320
clang::CallEnter
Represents a point when we begin processing an inlined call.
Definition: ProgramPoint.h:630
clang::ento::PathSensitiveBugReport::clearVisitors
void clearVisitors()
Remove all visitors attached to this bug report.
Definition: BugReporter.cpp:2173
clang::BlockEdge
Definition: ProgramPoint.h:503
clang::ento::PathSensitiveBugReport::isInteresting
bool isInteresting(SymbolRef sym) const
Definition: BugReporter.cpp:2369
clang::ento::ExplodedNode::getCurrentOrPreviousStmtForDiagnostics
const Stmt * getCurrentOrPreviousStmtForDiagnostics() const
Find the statement that was executed at or immediately before this node.
Definition: ExplodedGraph.cpp:386
clang::ento::PathDiagnosticPiece::ControlFlow
@ ControlFlow
Definition: PathDiagnostic.h:407
clang::ento::SVal
SVal - This represents a symbolic expression, which can be either an L-value or an R-value.
Definition: SVals.h:75
Parent
NodeId Parent
Definition: ASTDiff.cpp:192
clang::LocationContext::getCFG
CFG * getCFG() const
Definition: AnalysisDeclContext.h:249
Stmt.h
optimizeEdges
static bool optimizeEdges(const PathDiagnosticConstruct &C, PathPieces &path, OptimizedCallsSet &OCS)
Definition: BugReporter.cpp:1763
llvm::SmallVectorImpl
Definition: LLVM.h:39
clang::ento::MemRegion::getBaseRegion
const MemRegion * getBaseRegion() const
Definition: MemRegion.cpp:1292
clang::ParentMap::isConsumedExpr
bool isConsumedExpr(Expr *E) const
Definition: ParentMap.cpp:171
clang::Expr
This represents one expression.
Definition: Expr.h:109
SM
#define SM(sm)
Definition: Cuda.cpp:78
clang::FullSourceLoc::getLineNumber
unsigned getLineNumber(bool *Invalid=nullptr) const
Definition: SourceLocation.cpp:211
clang::ento::InterExplodedGraphMap
llvm::DenseMap< const ExplodedNode *, const ExplodedNode * > InterExplodedGraphMap
Definition: ExplodedGraph.h:302
clang::transformer::name
RangeSelector name(std::string ID)
Given a node with a "name", (like NamedDecl, DeclRefExpr, CxxCtorInitializer, and TypeLoc) selects th...
Definition: RangeSelector.cpp:200
getStmtParent
static const Stmt * getStmtParent(const Stmt *S, const ParentMap &PM)
Definition: BugReporter.cpp:1346
clang::ento::PathSensitiveBugReport::getLocation
PathDiagnosticLocation getLocation() const override
The primary location of the bug report that points at the undesirable behavior in the code.
Definition: BugReporter.cpp:2412
clang::ento::StackHintGeneratorForSymbol::getMessageForArg
virtual std::string getMessageForArg(const Expr *ArgE, unsigned ArgIndex)
Produces the message of the following form: 'Msg via Nth parameter'.
Definition: BugReporter.cpp:334
clang::LocationContext::getDecl
const Decl * getDecl() const
Definition: AnalysisDeclContext.h:247
clang::ProgramPoint
Definition: ProgramPoint.h:59
removeEdgesToDefaultInitializers
static void removeEdgesToDefaultInitializers(PathPieces &Pieces)
Remove edges in and out of C++ default initializer expressions.
Definition: BugReporter.cpp:529
StmtCXX.h
clang::ento::ExprEngine::getGraph
ExplodedGraph & getGraph()
Definition: ExprEngine.h:261
clang::ReturnStmt
ReturnStmt - This represents a return, optionally of an expression: return; return 4;.
Definition: Stmt.h:2760
clang::AnalyzerOptions::AnalyzeAll
unsigned AnalyzeAll
Definition: AnalyzerOptions.h:243
clang::LocationContext::getParentMap
const ParentMap & getParentMap() const
Definition: AnalysisDeclContext.h:253