clang  3.9.0
Consumed.cpp
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1 //===- Consumed.cpp --------------------------------------------*- C++ --*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // A intra-procedural analysis for checking consumed properties. This is based,
11 // in part, on research on linear types.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "clang/AST/ASTContext.h"
16 #include "clang/AST/Attr.h"
17 #include "clang/AST/DeclCXX.h"
18 #include "clang/AST/ExprCXX.h"
20 #include "clang/AST/StmtCXX.h"
21 #include "clang/AST/StmtVisitor.h"
22 #include "clang/AST/Type.h"
26 #include "clang/Analysis/CFG.h"
29 #include "llvm/ADT/DenseMap.h"
30 #include "llvm/ADT/SmallVector.h"
31 #include "llvm/Support/Compiler.h"
32 #include "llvm/Support/raw_ostream.h"
33 #include <memory>
34 
35 // TODO: Adjust states of args to constructors in the same way that arguments to
36 // function calls are handled.
37 // TODO: Use information from tests in for- and while-loop conditional.
38 // TODO: Add notes about the actual and expected state for
39 // TODO: Correctly identify unreachable blocks when chaining boolean operators.
40 // TODO: Adjust the parser and AttributesList class to support lists of
41 // identifiers.
42 // TODO: Warn about unreachable code.
43 // TODO: Switch to using a bitmap to track unreachable blocks.
44 // TODO: Handle variable definitions, e.g. bool valid = x.isValid();
45 // if (valid) ...; (Deferred)
46 // TODO: Take notes on state transitions to provide better warning messages.
47 // (Deferred)
48 // TODO: Test nested conditionals: A) Checking the same value multiple times,
49 // and 2) Checking different values. (Deferred)
50 
51 using namespace clang;
52 using namespace consumed;
53 
54 // Key method definition
56 
57 static SourceLocation getFirstStmtLoc(const CFGBlock *Block) {
58  // Find the source location of the first statement in the block, if the block
59  // is not empty.
60  for (const auto &B : *Block)
61  if (Optional<CFGStmt> CS = B.getAs<CFGStmt>())
62  return CS->getStmt()->getLocStart();
63 
64  // Block is empty.
65  // If we have one successor, return the first statement in that block
66  if (Block->succ_size() == 1 && *Block->succ_begin())
67  return getFirstStmtLoc(*Block->succ_begin());
68 
69  return SourceLocation();
70 }
71 
72 static SourceLocation getLastStmtLoc(const CFGBlock *Block) {
73  // Find the source location of the last statement in the block, if the block
74  // is not empty.
75  if (const Stmt *StmtNode = Block->getTerminator()) {
76  return StmtNode->getLocStart();
77  } else {
78  for (CFGBlock::const_reverse_iterator BI = Block->rbegin(),
79  BE = Block->rend(); BI != BE; ++BI) {
80  if (Optional<CFGStmt> CS = BI->getAs<CFGStmt>())
81  return CS->getStmt()->getLocStart();
82  }
83  }
84 
85  // If we have one successor, return the first statement in that block
86  SourceLocation Loc;
87  if (Block->succ_size() == 1 && *Block->succ_begin())
88  Loc = getFirstStmtLoc(*Block->succ_begin());
89  if (Loc.isValid())
90  return Loc;
91 
92  // If we have one predecessor, return the last statement in that block
93  if (Block->pred_size() == 1 && *Block->pred_begin())
94  return getLastStmtLoc(*Block->pred_begin());
95 
96  return Loc;
97 }
98 
100  switch (State) {
101  case CS_Unconsumed:
102  return CS_Consumed;
103  case CS_Consumed:
104  return CS_Unconsumed;
105  case CS_None:
106  return CS_None;
107  case CS_Unknown:
108  return CS_Unknown;
109  }
110  llvm_unreachable("invalid enum");
111 }
112 
113 static bool isCallableInState(const CallableWhenAttr *CWAttr,
115 
116  for (const auto &S : CWAttr->callableStates()) {
117  ConsumedState MappedAttrState = CS_None;
118 
119  switch (S) {
121  MappedAttrState = CS_Unknown;
122  break;
123 
124  case CallableWhenAttr::Unconsumed:
125  MappedAttrState = CS_Unconsumed;
126  break;
127 
128  case CallableWhenAttr::Consumed:
129  MappedAttrState = CS_Consumed;
130  break;
131  }
132 
133  if (MappedAttrState == State)
134  return true;
135  }
136 
137  return false;
138 }
139 
140 
141 static bool isConsumableType(const QualType &QT) {
142  if (QT->isPointerType() || QT->isReferenceType())
143  return false;
144 
145  if (const CXXRecordDecl *RD = QT->getAsCXXRecordDecl())
146  return RD->hasAttr<ConsumableAttr>();
147 
148  return false;
149 }
150 
151 static bool isAutoCastType(const QualType &QT) {
152  if (QT->isPointerType() || QT->isReferenceType())
153  return false;
154 
155  if (const CXXRecordDecl *RD = QT->getAsCXXRecordDecl())
156  return RD->hasAttr<ConsumableAutoCastAttr>();
157 
158  return false;
159 }
160 
161 static bool isSetOnReadPtrType(const QualType &QT) {
162  if (const CXXRecordDecl *RD = QT->getPointeeCXXRecordDecl())
163  return RD->hasAttr<ConsumableSetOnReadAttr>();
164  return false;
165 }
166 
167 
169  switch (State) {
170  case CS_Unconsumed:
171  case CS_Consumed:
172  return true;
173  case CS_None:
174  case CS_Unknown:
175  return false;
176  }
177  llvm_unreachable("invalid enum");
178 }
179 
180 static bool isRValueRef(QualType ParamType) {
181  return ParamType->isRValueReferenceType();
182 }
183 
184 static bool isTestingFunction(const FunctionDecl *FunDecl) {
185  return FunDecl->hasAttr<TestTypestateAttr>();
186 }
187 
188 static bool isPointerOrRef(QualType ParamType) {
189  return ParamType->isPointerType() || ParamType->isReferenceType();
190 }
191 
193  assert(isConsumableType(QT));
194 
195  const ConsumableAttr *CAttr =
196  QT->getAsCXXRecordDecl()->getAttr<ConsumableAttr>();
197 
198  switch (CAttr->getDefaultState()) {
200  return CS_Unknown;
201  case ConsumableAttr::Unconsumed:
202  return CS_Unconsumed;
203  case ConsumableAttr::Consumed:
204  return CS_Consumed;
205  }
206  llvm_unreachable("invalid enum");
207 }
208 
209 static ConsumedState
210 mapParamTypestateAttrState(const ParamTypestateAttr *PTAttr) {
211  switch (PTAttr->getParamState()) {
213  return CS_Unknown;
214  case ParamTypestateAttr::Unconsumed:
215  return CS_Unconsumed;
216  case ParamTypestateAttr::Consumed:
217  return CS_Consumed;
218  }
219  llvm_unreachable("invalid_enum");
220 }
221 
222 static ConsumedState
223 mapReturnTypestateAttrState(const ReturnTypestateAttr *RTSAttr) {
224  switch (RTSAttr->getState()) {
226  return CS_Unknown;
227  case ReturnTypestateAttr::Unconsumed:
228  return CS_Unconsumed;
229  case ReturnTypestateAttr::Consumed:
230  return CS_Consumed;
231  }
232  llvm_unreachable("invalid enum");
233 }
234 
235 static ConsumedState mapSetTypestateAttrState(const SetTypestateAttr *STAttr) {
236  switch (STAttr->getNewState()) {
238  return CS_Unknown;
239  case SetTypestateAttr::Unconsumed:
240  return CS_Unconsumed;
241  case SetTypestateAttr::Consumed:
242  return CS_Consumed;
243  }
244  llvm_unreachable("invalid_enum");
245 }
246 
247 static StringRef stateToString(ConsumedState State) {
248  switch (State) {
249  case consumed::CS_None:
250  return "none";
251 
253  return "unknown";
254 
256  return "unconsumed";
257 
259  return "consumed";
260  }
261  llvm_unreachable("invalid enum");
262 }
263 
264 static ConsumedState testsFor(const FunctionDecl *FunDecl) {
265  assert(isTestingFunction(FunDecl));
266  switch (FunDecl->getAttr<TestTypestateAttr>()->getTestState()) {
267  case TestTypestateAttr::Unconsumed:
268  return CS_Unconsumed;
269  case TestTypestateAttr::Consumed:
270  return CS_Consumed;
271  }
272  llvm_unreachable("invalid enum");
273 }
274 
275 namespace {
276 struct VarTestResult {
277  const VarDecl *Var;
278  ConsumedState TestsFor;
279 };
280 } // end anonymous::VarTestResult
281 
282 namespace clang {
283 namespace consumed {
284 
288 };
289 
291  enum {
292  IT_None,
293  IT_State,
294  IT_VarTest,
295  IT_BinTest,
296  IT_Var,
297  IT_Tmp
298  } InfoType;
299 
300  struct BinTestTy {
301  const BinaryOperator *Source;
302  EffectiveOp EOp;
303  VarTestResult LTest;
304  VarTestResult RTest;
305  };
306 
307  union {
309  VarTestResult VarTest;
310  const VarDecl *Var;
312  BinTestTy BinTest;
313  };
314 
315 public:
316  PropagationInfo() : InfoType(IT_None) {}
317 
318  PropagationInfo(const VarTestResult &VarTest)
319  : InfoType(IT_VarTest), VarTest(VarTest) {}
320 
321  PropagationInfo(const VarDecl *Var, ConsumedState TestsFor)
322  : InfoType(IT_VarTest) {
323 
324  VarTest.Var = Var;
325  VarTest.TestsFor = TestsFor;
326  }
327 
329  const VarTestResult &LTest, const VarTestResult &RTest)
330  : InfoType(IT_BinTest) {
331 
332  BinTest.Source = Source;
333  BinTest.EOp = EOp;
334  BinTest.LTest = LTest;
335  BinTest.RTest = RTest;
336  }
337 
339  const VarDecl *LVar, ConsumedState LTestsFor,
340  const VarDecl *RVar, ConsumedState RTestsFor)
341  : InfoType(IT_BinTest) {
342 
343  BinTest.Source = Source;
344  BinTest.EOp = EOp;
345  BinTest.LTest.Var = LVar;
346  BinTest.LTest.TestsFor = LTestsFor;
347  BinTest.RTest.Var = RVar;
348  BinTest.RTest.TestsFor = RTestsFor;
349  }
350 
352  : InfoType(IT_State), State(State) {}
353 
354  PropagationInfo(const VarDecl *Var) : InfoType(IT_Var), Var(Var) {}
356  : InfoType(IT_Tmp), Tmp(Tmp) {}
357 
358  const ConsumedState & getState() const {
359  assert(InfoType == IT_State);
360  return State;
361  }
362 
363  const VarTestResult & getVarTest() const {
364  assert(InfoType == IT_VarTest);
365  return VarTest;
366  }
367 
368  const VarTestResult & getLTest() const {
369  assert(InfoType == IT_BinTest);
370  return BinTest.LTest;
371  }
372 
373  const VarTestResult & getRTest() const {
374  assert(InfoType == IT_BinTest);
375  return BinTest.RTest;
376  }
377 
378  const VarDecl * getVar() const {
379  assert(InfoType == IT_Var);
380  return Var;
381  }
382 
383  const CXXBindTemporaryExpr * getTmp() const {
384  assert(InfoType == IT_Tmp);
385  return Tmp;
386  }
387 
388  ConsumedState getAsState(const ConsumedStateMap *StateMap) const {
389  assert(isVar() || isTmp() || isState());
390 
391  if (isVar())
392  return StateMap->getState(Var);
393  else if (isTmp())
394  return StateMap->getState(Tmp);
395  else if (isState())
396  return State;
397  else
398  return CS_None;
399  }
400 
402  assert(InfoType == IT_BinTest);
403  return BinTest.EOp;
404  }
405 
406  const BinaryOperator * testSourceNode() const {
407  assert(InfoType == IT_BinTest);
408  return BinTest.Source;
409  }
410 
411  inline bool isValid() const { return InfoType != IT_None; }
412  inline bool isState() const { return InfoType == IT_State; }
413  inline bool isVarTest() const { return InfoType == IT_VarTest; }
414  inline bool isBinTest() const { return InfoType == IT_BinTest; }
415  inline bool isVar() const { return InfoType == IT_Var; }
416  inline bool isTmp() const { return InfoType == IT_Tmp; }
417 
418  bool isTest() const {
419  return InfoType == IT_VarTest || InfoType == IT_BinTest;
420  }
421 
422  bool isPointerToValue() const {
423  return InfoType == IT_Var || InfoType == IT_Tmp;
424  }
425 
427  assert(InfoType == IT_VarTest || InfoType == IT_BinTest);
428 
429  if (InfoType == IT_VarTest) {
430  return PropagationInfo(VarTest.Var,
431  invertConsumedUnconsumed(VarTest.TestsFor));
432 
433  } else if (InfoType == IT_BinTest) {
434  return PropagationInfo(BinTest.Source,
435  BinTest.EOp == EO_And ? EO_Or : EO_And,
436  BinTest.LTest.Var, invertConsumedUnconsumed(BinTest.LTest.TestsFor),
437  BinTest.RTest.Var, invertConsumedUnconsumed(BinTest.RTest.TestsFor));
438  } else {
439  return PropagationInfo();
440  }
441  }
442 };
443 
444 static inline void
447 
448  assert(PInfo.isVar() || PInfo.isTmp());
449 
450  if (PInfo.isVar())
451  StateMap->setState(PInfo.getVar(), State);
452  else
453  StateMap->setState(PInfo.getTmp(), State);
454 }
455 
456 class ConsumedStmtVisitor : public ConstStmtVisitor<ConsumedStmtVisitor> {
457 
458  typedef llvm::DenseMap<const Stmt *, PropagationInfo> MapType;
459  typedef std::pair<const Stmt *, PropagationInfo> PairType;
460  typedef MapType::iterator InfoEntry;
461  typedef MapType::const_iterator ConstInfoEntry;
462 
464  ConsumedAnalyzer &Analyzer;
465  ConsumedStateMap *StateMap;
466  MapType PropagationMap;
467 
468  InfoEntry findInfo(const Expr *E) {
469  if (auto Cleanups = dyn_cast<ExprWithCleanups>(E))
470  if (!Cleanups->cleanupsHaveSideEffects())
471  E = Cleanups->getSubExpr();
472  return PropagationMap.find(E->IgnoreParens());
473  }
474  ConstInfoEntry findInfo(const Expr *E) const {
475  if (auto Cleanups = dyn_cast<ExprWithCleanups>(E))
476  if (!Cleanups->cleanupsHaveSideEffects())
477  E = Cleanups->getSubExpr();
478  return PropagationMap.find(E->IgnoreParens());
479  }
480  void insertInfo(const Expr *E, const PropagationInfo &PI) {
481  PropagationMap.insert(PairType(E->IgnoreParens(), PI));
482  }
483 
484  void forwardInfo(const Expr *From, const Expr *To);
485  void copyInfo(const Expr *From, const Expr *To, ConsumedState CS);
486  ConsumedState getInfo(const Expr *From);
487  void setInfo(const Expr *To, ConsumedState NS);
488  void propagateReturnType(const Expr *Call, const FunctionDecl *Fun);
489 
490 public:
491  void checkCallability(const PropagationInfo &PInfo,
492  const FunctionDecl *FunDecl,
493  SourceLocation BlameLoc);
494  bool handleCall(const CallExpr *Call, const Expr *ObjArg,
495  const FunctionDecl *FunD);
496 
497  void VisitBinaryOperator(const BinaryOperator *BinOp);
498  void VisitCallExpr(const CallExpr *Call);
499  void VisitCastExpr(const CastExpr *Cast);
500  void VisitCXXBindTemporaryExpr(const CXXBindTemporaryExpr *Temp);
501  void VisitCXXConstructExpr(const CXXConstructExpr *Call);
502  void VisitCXXMemberCallExpr(const CXXMemberCallExpr *Call);
503  void VisitCXXOperatorCallExpr(const CXXOperatorCallExpr *Call);
504  void VisitDeclRefExpr(const DeclRefExpr *DeclRef);
505  void VisitDeclStmt(const DeclStmt *DelcS);
506  void VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *Temp);
507  void VisitMemberExpr(const MemberExpr *MExpr);
508  void VisitParmVarDecl(const ParmVarDecl *Param);
509  void VisitReturnStmt(const ReturnStmt *Ret);
510  void VisitUnaryOperator(const UnaryOperator *UOp);
511  void VisitVarDecl(const VarDecl *Var);
512 
514  ConsumedStateMap *StateMap)
515  : AC(AC), Analyzer(Analyzer), StateMap(StateMap) {}
516 
517  PropagationInfo getInfo(const Expr *StmtNode) const {
518  ConstInfoEntry Entry = findInfo(StmtNode);
519 
520  if (Entry != PropagationMap.end())
521  return Entry->second;
522  else
523  return PropagationInfo();
524  }
525 
526  void reset(ConsumedStateMap *NewStateMap) {
527  StateMap = NewStateMap;
528  }
529 };
530 
531 
532 void ConsumedStmtVisitor::forwardInfo(const Expr *From, const Expr *To) {
533  InfoEntry Entry = findInfo(From);
534  if (Entry != PropagationMap.end())
535  insertInfo(To, Entry->second);
536 }
537 
538 
539 // Create a new state for To, which is initialized to the state of From.
540 // If NS is not CS_None, sets the state of From to NS.
541 void ConsumedStmtVisitor::copyInfo(const Expr *From, const Expr *To,
542  ConsumedState NS) {
543  InfoEntry Entry = findInfo(From);
544  if (Entry != PropagationMap.end()) {
545  PropagationInfo& PInfo = Entry->second;
546  ConsumedState CS = PInfo.getAsState(StateMap);
547  if (CS != CS_None)
548  insertInfo(To, PropagationInfo(CS));
549  if (NS != CS_None && PInfo.isPointerToValue())
550  setStateForVarOrTmp(StateMap, PInfo, NS);
551  }
552 }
553 
554 
555 // Get the ConsumedState for From
556 ConsumedState ConsumedStmtVisitor::getInfo(const Expr *From) {
557  InfoEntry Entry = findInfo(From);
558  if (Entry != PropagationMap.end()) {
559  PropagationInfo& PInfo = Entry->second;
560  return PInfo.getAsState(StateMap);
561  }
562  return CS_None;
563 }
564 
565 
566 // If we already have info for To then update it, otherwise create a new entry.
567 void ConsumedStmtVisitor::setInfo(const Expr *To, ConsumedState NS) {
568  InfoEntry Entry = findInfo(To);
569  if (Entry != PropagationMap.end()) {
570  PropagationInfo& PInfo = Entry->second;
571  if (PInfo.isPointerToValue())
572  setStateForVarOrTmp(StateMap, PInfo, NS);
573  } else if (NS != CS_None) {
574  insertInfo(To, PropagationInfo(NS));
575  }
576 }
577 
578 
579 
581  const FunctionDecl *FunDecl,
582  SourceLocation BlameLoc) {
583  assert(!PInfo.isTest());
584 
585  const CallableWhenAttr *CWAttr = FunDecl->getAttr<CallableWhenAttr>();
586  if (!CWAttr)
587  return;
588 
589  if (PInfo.isVar()) {
590  ConsumedState VarState = StateMap->getState(PInfo.getVar());
591 
592  if (VarState == CS_None || isCallableInState(CWAttr, VarState))
593  return;
594 
595  Analyzer.WarningsHandler.warnUseInInvalidState(
596  FunDecl->getNameAsString(), PInfo.getVar()->getNameAsString(),
597  stateToString(VarState), BlameLoc);
598 
599  } else {
600  ConsumedState TmpState = PInfo.getAsState(StateMap);
601 
602  if (TmpState == CS_None || isCallableInState(CWAttr, TmpState))
603  return;
604 
605  Analyzer.WarningsHandler.warnUseOfTempInInvalidState(
606  FunDecl->getNameAsString(), stateToString(TmpState), BlameLoc);
607  }
608 }
609 
610 
611 // Factors out common behavior for function, method, and operator calls.
612 // Check parameters and set parameter state if necessary.
613 // Returns true if the state of ObjArg is set, or false otherwise.
614 bool ConsumedStmtVisitor::handleCall(const CallExpr *Call, const Expr *ObjArg,
615  const FunctionDecl *FunD) {
616  unsigned Offset = 0;
617  if (isa<CXXOperatorCallExpr>(Call) && isa<CXXMethodDecl>(FunD))
618  Offset = 1; // first argument is 'this'
619 
620  // check explicit parameters
621  for (unsigned Index = Offset; Index < Call->getNumArgs(); ++Index) {
622  // Skip variable argument lists.
623  if (Index - Offset >= FunD->getNumParams())
624  break;
625 
626  const ParmVarDecl *Param = FunD->getParamDecl(Index - Offset);
627  QualType ParamType = Param->getType();
628 
629  InfoEntry Entry = findInfo(Call->getArg(Index));
630 
631  if (Entry == PropagationMap.end() || Entry->second.isTest())
632  continue;
633  PropagationInfo PInfo = Entry->second;
634 
635  // Check that the parameter is in the correct state.
636  if (ParamTypestateAttr *PTA = Param->getAttr<ParamTypestateAttr>()) {
637  ConsumedState ParamState = PInfo.getAsState(StateMap);
638  ConsumedState ExpectedState = mapParamTypestateAttrState(PTA);
639 
640  if (ParamState != ExpectedState)
641  Analyzer.WarningsHandler.warnParamTypestateMismatch(
642  Call->getArg(Index)->getExprLoc(),
643  stateToString(ExpectedState), stateToString(ParamState));
644  }
645 
646  if (!(Entry->second.isVar() || Entry->second.isTmp()))
647  continue;
648 
649  // Adjust state on the caller side.
650  if (isRValueRef(ParamType))
651  setStateForVarOrTmp(StateMap, PInfo, consumed::CS_Consumed);
652  else if (ReturnTypestateAttr *RT = Param->getAttr<ReturnTypestateAttr>())
653  setStateForVarOrTmp(StateMap, PInfo, mapReturnTypestateAttrState(RT));
654  else if (isPointerOrRef(ParamType) &&
655  (!ParamType->getPointeeType().isConstQualified() ||
656  isSetOnReadPtrType(ParamType)))
657  setStateForVarOrTmp(StateMap, PInfo, consumed::CS_Unknown);
658  }
659 
660  if (!ObjArg)
661  return false;
662 
663  // check implicit 'self' parameter, if present
664  InfoEntry Entry = findInfo(ObjArg);
665  if (Entry != PropagationMap.end()) {
666  PropagationInfo PInfo = Entry->second;
667  checkCallability(PInfo, FunD, Call->getExprLoc());
668 
669  if (SetTypestateAttr *STA = FunD->getAttr<SetTypestateAttr>()) {
670  if (PInfo.isVar()) {
671  StateMap->setState(PInfo.getVar(), mapSetTypestateAttrState(STA));
672  return true;
673  }
674  else if (PInfo.isTmp()) {
675  StateMap->setState(PInfo.getTmp(), mapSetTypestateAttrState(STA));
676  return true;
677  }
678  }
679  else if (isTestingFunction(FunD) && PInfo.isVar()) {
680  PropagationMap.insert(PairType(Call,
681  PropagationInfo(PInfo.getVar(), testsFor(FunD))));
682  }
683  }
684  return false;
685 }
686 
687 
688 void ConsumedStmtVisitor::propagateReturnType(const Expr *Call,
689  const FunctionDecl *Fun) {
690  QualType RetType = Fun->getCallResultType();
691  if (RetType->isReferenceType())
692  RetType = RetType->getPointeeType();
693 
694  if (isConsumableType(RetType)) {
695  ConsumedState ReturnState;
696  if (ReturnTypestateAttr *RTA = Fun->getAttr<ReturnTypestateAttr>())
697  ReturnState = mapReturnTypestateAttrState(RTA);
698  else
699  ReturnState = mapConsumableAttrState(RetType);
700 
701  PropagationMap.insert(PairType(Call, PropagationInfo(ReturnState)));
702  }
703 }
704 
705 
707  switch (BinOp->getOpcode()) {
708  case BO_LAnd:
709  case BO_LOr : {
710  InfoEntry LEntry = findInfo(BinOp->getLHS()),
711  REntry = findInfo(BinOp->getRHS());
712 
713  VarTestResult LTest, RTest;
714 
715  if (LEntry != PropagationMap.end() && LEntry->second.isVarTest()) {
716  LTest = LEntry->second.getVarTest();
717 
718  } else {
719  LTest.Var = nullptr;
720  LTest.TestsFor = CS_None;
721  }
722 
723  if (REntry != PropagationMap.end() && REntry->second.isVarTest()) {
724  RTest = REntry->second.getVarTest();
725 
726  } else {
727  RTest.Var = nullptr;
728  RTest.TestsFor = CS_None;
729  }
730 
731  if (!(LTest.Var == nullptr && RTest.Var == nullptr))
732  PropagationMap.insert(PairType(BinOp, PropagationInfo(BinOp,
733  static_cast<EffectiveOp>(BinOp->getOpcode() == BO_LOr), LTest, RTest)));
734 
735  break;
736  }
737 
738  case BO_PtrMemD:
739  case BO_PtrMemI:
740  forwardInfo(BinOp->getLHS(), BinOp);
741  break;
742 
743  default:
744  break;
745  }
746 }
747 
749  const FunctionDecl *FunDecl = Call->getDirectCallee();
750  if (!FunDecl)
751  return;
752 
753  // Special case for the std::move function.
754  // TODO: Make this more specific. (Deferred)
755  if (Call->getNumArgs() == 1 && FunDecl->getNameAsString() == "move" &&
756  FunDecl->isInStdNamespace()) {
757  copyInfo(Call->getArg(0), Call, CS_Consumed);
758  return;
759  }
760 
761  handleCall(Call, nullptr, FunDecl);
762  propagateReturnType(Call, FunDecl);
763 }
764 
766  forwardInfo(Cast->getSubExpr(), Cast);
767 }
768 
770  const CXXBindTemporaryExpr *Temp) {
771 
772  InfoEntry Entry = findInfo(Temp->getSubExpr());
773 
774  if (Entry != PropagationMap.end() && !Entry->second.isTest()) {
775  StateMap->setState(Temp, Entry->second.getAsState(StateMap));
776  PropagationMap.insert(PairType(Temp, PropagationInfo(Temp)));
777  }
778 }
779 
781  CXXConstructorDecl *Constructor = Call->getConstructor();
782 
783  ASTContext &CurrContext = AC.getASTContext();
784  QualType ThisType = Constructor->getThisType(CurrContext)->getPointeeType();
785 
786  if (!isConsumableType(ThisType))
787  return;
788 
789  // FIXME: What should happen if someone annotates the move constructor?
790  if (ReturnTypestateAttr *RTA = Constructor->getAttr<ReturnTypestateAttr>()) {
791  // TODO: Adjust state of args appropriately.
793  PropagationMap.insert(PairType(Call, PropagationInfo(RetState)));
794  } else if (Constructor->isDefaultConstructor()) {
795  PropagationMap.insert(PairType(Call,
797  } else if (Constructor->isMoveConstructor()) {
798  copyInfo(Call->getArg(0), Call, CS_Consumed);
799  } else if (Constructor->isCopyConstructor()) {
800  // Copy state from arg. If setStateOnRead then set arg to CS_Unknown.
801  ConsumedState NS =
802  isSetOnReadPtrType(Constructor->getThisType(CurrContext)) ?
804  copyInfo(Call->getArg(0), Call, NS);
805  } else {
806  // TODO: Adjust state of args appropriately.
807  ConsumedState RetState = mapConsumableAttrState(ThisType);
808  PropagationMap.insert(PairType(Call, PropagationInfo(RetState)));
809  }
810 }
811 
812 
814  const CXXMemberCallExpr *Call) {
815  CXXMethodDecl* MD = Call->getMethodDecl();
816  if (!MD)
817  return;
818 
819  handleCall(Call, Call->getImplicitObjectArgument(), MD);
820  propagateReturnType(Call, MD);
821 }
822 
823 
825  const CXXOperatorCallExpr *Call) {
826 
827  const FunctionDecl *FunDecl =
828  dyn_cast_or_null<FunctionDecl>(Call->getDirectCallee());
829  if (!FunDecl) return;
830 
831  if (Call->getOperator() == OO_Equal) {
832  ConsumedState CS = getInfo(Call->getArg(1));
833  if (!handleCall(Call, Call->getArg(0), FunDecl))
834  setInfo(Call->getArg(0), CS);
835  return;
836  }
837 
838  if (const CXXMemberCallExpr *MCall = dyn_cast<CXXMemberCallExpr>(Call))
839  handleCall(MCall, MCall->getImplicitObjectArgument(), FunDecl);
840  else
841  handleCall(Call, Call->getArg(0), FunDecl);
842 
843  propagateReturnType(Call, FunDecl);
844 }
845 
847  if (const VarDecl *Var = dyn_cast_or_null<VarDecl>(DeclRef->getDecl()))
848  if (StateMap->getState(Var) != consumed::CS_None)
849  PropagationMap.insert(PairType(DeclRef, PropagationInfo(Var)));
850 }
851 
853  for (const auto *DI : DeclS->decls())
854  if (isa<VarDecl>(DI))
855  VisitVarDecl(cast<VarDecl>(DI));
856 
857  if (DeclS->isSingleDecl())
858  if (const VarDecl *Var = dyn_cast_or_null<VarDecl>(DeclS->getSingleDecl()))
859  PropagationMap.insert(PairType(DeclS, PropagationInfo(Var)));
860 }
861 
863  const MaterializeTemporaryExpr *Temp) {
864 
865  forwardInfo(Temp->GetTemporaryExpr(), Temp);
866 }
867 
869  forwardInfo(MExpr->getBase(), MExpr);
870 }
871 
872 
874  QualType ParamType = Param->getType();
875  ConsumedState ParamState = consumed::CS_None;
876 
877  if (const ParamTypestateAttr *PTA = Param->getAttr<ParamTypestateAttr>())
878  ParamState = mapParamTypestateAttrState(PTA);
879  else if (isConsumableType(ParamType))
880  ParamState = mapConsumableAttrState(ParamType);
881  else if (isRValueRef(ParamType) &&
882  isConsumableType(ParamType->getPointeeType()))
883  ParamState = mapConsumableAttrState(ParamType->getPointeeType());
884  else if (ParamType->isReferenceType() &&
885  isConsumableType(ParamType->getPointeeType()))
886  ParamState = consumed::CS_Unknown;
887 
888  if (ParamState != CS_None)
889  StateMap->setState(Param, ParamState);
890 }
891 
893  ConsumedState ExpectedState = Analyzer.getExpectedReturnState();
894 
895  if (ExpectedState != CS_None) {
896  InfoEntry Entry = findInfo(Ret->getRetValue());
897 
898  if (Entry != PropagationMap.end()) {
899  ConsumedState RetState = Entry->second.getAsState(StateMap);
900 
901  if (RetState != ExpectedState)
902  Analyzer.WarningsHandler.warnReturnTypestateMismatch(
903  Ret->getReturnLoc(), stateToString(ExpectedState),
904  stateToString(RetState));
905  }
906  }
907 
908  StateMap->checkParamsForReturnTypestate(Ret->getLocStart(),
909  Analyzer.WarningsHandler);
910 }
911 
913  InfoEntry Entry = findInfo(UOp->getSubExpr());
914  if (Entry == PropagationMap.end()) return;
915 
916  switch (UOp->getOpcode()) {
917  case UO_AddrOf:
918  PropagationMap.insert(PairType(UOp, Entry->second));
919  break;
920 
921  case UO_LNot:
922  if (Entry->second.isTest())
923  PropagationMap.insert(PairType(UOp, Entry->second.invertTest()));
924  break;
925 
926  default:
927  break;
928  }
929 }
930 
931 // TODO: See if I need to check for reference types here.
933  if (isConsumableType(Var->getType())) {
934  if (Var->hasInit()) {
935  MapType::iterator VIT = findInfo(Var->getInit()->IgnoreImplicit());
936  if (VIT != PropagationMap.end()) {
937  PropagationInfo PInfo = VIT->second;
938  ConsumedState St = PInfo.getAsState(StateMap);
939 
940  if (St != consumed::CS_None) {
941  StateMap->setState(Var, St);
942  return;
943  }
944  }
945  }
946  // Otherwise
947  StateMap->setState(Var, consumed::CS_Unknown);
948  }
949 }
950 }} // end clang::consumed::ConsumedStmtVisitor
951 
952 namespace clang {
953 namespace consumed {
954 
955 static void splitVarStateForIf(const IfStmt *IfNode, const VarTestResult &Test,
956  ConsumedStateMap *ThenStates,
957  ConsumedStateMap *ElseStates) {
958  ConsumedState VarState = ThenStates->getState(Test.Var);
959 
960  if (VarState == CS_Unknown) {
961  ThenStates->setState(Test.Var, Test.TestsFor);
962  ElseStates->setState(Test.Var, invertConsumedUnconsumed(Test.TestsFor));
963 
964  } else if (VarState == invertConsumedUnconsumed(Test.TestsFor)) {
965  ThenStates->markUnreachable();
966 
967  } else if (VarState == Test.TestsFor) {
968  ElseStates->markUnreachable();
969  }
970 }
971 
972 static void splitVarStateForIfBinOp(const PropagationInfo &PInfo,
973  ConsumedStateMap *ThenStates,
974  ConsumedStateMap *ElseStates) {
975  const VarTestResult &LTest = PInfo.getLTest(),
976  &RTest = PInfo.getRTest();
977 
978  ConsumedState LState = LTest.Var ? ThenStates->getState(LTest.Var) : CS_None,
979  RState = RTest.Var ? ThenStates->getState(RTest.Var) : CS_None;
980 
981  if (LTest.Var) {
982  if (PInfo.testEffectiveOp() == EO_And) {
983  if (LState == CS_Unknown) {
984  ThenStates->setState(LTest.Var, LTest.TestsFor);
985 
986  } else if (LState == invertConsumedUnconsumed(LTest.TestsFor)) {
987  ThenStates->markUnreachable();
988 
989  } else if (LState == LTest.TestsFor && isKnownState(RState)) {
990  if (RState == RTest.TestsFor)
991  ElseStates->markUnreachable();
992  else
993  ThenStates->markUnreachable();
994  }
995 
996  } else {
997  if (LState == CS_Unknown) {
998  ElseStates->setState(LTest.Var,
999  invertConsumedUnconsumed(LTest.TestsFor));
1000 
1001  } else if (LState == LTest.TestsFor) {
1002  ElseStates->markUnreachable();
1003 
1004  } else if (LState == invertConsumedUnconsumed(LTest.TestsFor) &&
1005  isKnownState(RState)) {
1006 
1007  if (RState == RTest.TestsFor)
1008  ElseStates->markUnreachable();
1009  else
1010  ThenStates->markUnreachable();
1011  }
1012  }
1013  }
1014 
1015  if (RTest.Var) {
1016  if (PInfo.testEffectiveOp() == EO_And) {
1017  if (RState == CS_Unknown)
1018  ThenStates->setState(RTest.Var, RTest.TestsFor);
1019  else if (RState == invertConsumedUnconsumed(RTest.TestsFor))
1020  ThenStates->markUnreachable();
1021 
1022  } else {
1023  if (RState == CS_Unknown)
1024  ElseStates->setState(RTest.Var,
1025  invertConsumedUnconsumed(RTest.TestsFor));
1026  else if (RState == RTest.TestsFor)
1027  ElseStates->markUnreachable();
1028  }
1029  }
1030 }
1031 
1033  const CFGBlock *TargetBlock) {
1034 
1035  assert(CurrBlock && "Block pointer must not be NULL");
1036  assert(TargetBlock && "TargetBlock pointer must not be NULL");
1037 
1038  unsigned int CurrBlockOrder = VisitOrder[CurrBlock->getBlockID()];
1039  for (CFGBlock::const_pred_iterator PI = TargetBlock->pred_begin(),
1040  PE = TargetBlock->pred_end(); PI != PE; ++PI) {
1041  if (*PI && CurrBlockOrder < VisitOrder[(*PI)->getBlockID()] )
1042  return false;
1043  }
1044  return true;
1045 }
1046 
1048  const CFGBlock *Block, ConsumedStateMap *StateMap,
1049  std::unique_ptr<ConsumedStateMap> &OwnedStateMap) {
1050 
1051  assert(Block && "Block pointer must not be NULL");
1052 
1053  auto &Entry = StateMapsArray[Block->getBlockID()];
1054 
1055  if (Entry) {
1056  Entry->intersect(*StateMap);
1057  } else if (OwnedStateMap)
1058  Entry = std::move(OwnedStateMap);
1059  else
1060  Entry = llvm::make_unique<ConsumedStateMap>(*StateMap);
1061 }
1062 
1064  std::unique_ptr<ConsumedStateMap> StateMap) {
1065 
1066  assert(Block && "Block pointer must not be NULL");
1067 
1068  auto &Entry = StateMapsArray[Block->getBlockID()];
1069 
1070  if (Entry) {
1071  Entry->intersect(*StateMap);
1072  } else {
1073  Entry = std::move(StateMap);
1074  }
1075 }
1076 
1078  assert(Block && "Block pointer must not be NULL");
1079  assert(StateMapsArray[Block->getBlockID()] && "Block has no block info");
1080 
1081  return StateMapsArray[Block->getBlockID()].get();
1082 }
1083 
1085  StateMapsArray[Block->getBlockID()] = nullptr;
1086 }
1087 
1088 std::unique_ptr<ConsumedStateMap>
1090  assert(Block && "Block pointer must not be NULL");
1091 
1092  auto &Entry = StateMapsArray[Block->getBlockID()];
1093  return isBackEdgeTarget(Block) ? llvm::make_unique<ConsumedStateMap>(*Entry)
1094  : std::move(Entry);
1095 }
1096 
1097 bool ConsumedBlockInfo::isBackEdge(const CFGBlock *From, const CFGBlock *To) {
1098  assert(From && "From block must not be NULL");
1099  assert(To && "From block must not be NULL");
1100 
1101  return VisitOrder[From->getBlockID()] > VisitOrder[To->getBlockID()];
1102 }
1103 
1105  assert(Block && "Block pointer must not be NULL");
1106 
1107  // Anything with less than two predecessors can't be the target of a back
1108  // edge.
1109  if (Block->pred_size() < 2)
1110  return false;
1111 
1112  unsigned int BlockVisitOrder = VisitOrder[Block->getBlockID()];
1113  for (CFGBlock::const_pred_iterator PI = Block->pred_begin(),
1114  PE = Block->pred_end(); PI != PE; ++PI) {
1115  if (*PI && BlockVisitOrder < VisitOrder[(*PI)->getBlockID()])
1116  return true;
1117  }
1118  return false;
1119 }
1120 
1122  ConsumedWarningsHandlerBase &WarningsHandler) const {
1123 
1124  for (const auto &DM : VarMap) {
1125  if (isa<ParmVarDecl>(DM.first)) {
1126  const ParmVarDecl *Param = cast<ParmVarDecl>(DM.first);
1127  const ReturnTypestateAttr *RTA = Param->getAttr<ReturnTypestateAttr>();
1128 
1129  if (!RTA)
1130  continue;
1131 
1132  ConsumedState ExpectedState = mapReturnTypestateAttrState(RTA);
1133  if (DM.second != ExpectedState)
1134  WarningsHandler.warnParamReturnTypestateMismatch(BlameLoc,
1135  Param->getNameAsString(), stateToString(ExpectedState),
1136  stateToString(DM.second));
1137  }
1138  }
1139 }
1140 
1142  TmpMap.clear();
1143 }
1144 
1146  VarMapType::const_iterator Entry = VarMap.find(Var);
1147 
1148  if (Entry != VarMap.end())
1149  return Entry->second;
1150 
1151  return CS_None;
1152 }
1153 
1156  TmpMapType::const_iterator Entry = TmpMap.find(Tmp);
1157 
1158  if (Entry != TmpMap.end())
1159  return Entry->second;
1160 
1161  return CS_None;
1162 }
1163 
1165  ConsumedState LocalState;
1166 
1167  if (this->From && this->From == Other.From && !Other.Reachable) {
1168  this->markUnreachable();
1169  return;
1170  }
1171 
1172  for (const auto &DM : Other.VarMap) {
1173  LocalState = this->getState(DM.first);
1174 
1175  if (LocalState == CS_None)
1176  continue;
1177 
1178  if (LocalState != DM.second)
1179  VarMap[DM.first] = CS_Unknown;
1180  }
1181 }
1182 
1184  const CFGBlock *LoopBack, const ConsumedStateMap *LoopBackStates,
1185  ConsumedWarningsHandlerBase &WarningsHandler) {
1186 
1187  ConsumedState LocalState;
1188  SourceLocation BlameLoc = getLastStmtLoc(LoopBack);
1189 
1190  for (const auto &DM : LoopBackStates->VarMap) {
1191  LocalState = this->getState(DM.first);
1192 
1193  if (LocalState == CS_None)
1194  continue;
1195 
1196  if (LocalState != DM.second) {
1197  VarMap[DM.first] = CS_Unknown;
1198  WarningsHandler.warnLoopStateMismatch(BlameLoc,
1199  DM.first->getNameAsString());
1200  }
1201  }
1202 }
1203 
1205  this->Reachable = false;
1206  VarMap.clear();
1207  TmpMap.clear();
1208 }
1209 
1211  VarMap[Var] = State;
1212 }
1213 
1215  ConsumedState State) {
1216  TmpMap[Tmp] = State;
1217 }
1218 
1220  TmpMap.erase(Tmp);
1221 }
1222 
1224  for (const auto &DM : Other->VarMap)
1225  if (this->getState(DM.first) != DM.second)
1226  return true;
1227  return false;
1228 }
1229 
1230 void ConsumedAnalyzer::determineExpectedReturnState(AnalysisDeclContext &AC,
1231  const FunctionDecl *D) {
1232  QualType ReturnType;
1233  if (const CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) {
1234  ASTContext &CurrContext = AC.getASTContext();
1235  ReturnType = Constructor->getThisType(CurrContext)->getPointeeType();
1236  } else
1237  ReturnType = D->getCallResultType();
1238 
1239  if (const ReturnTypestateAttr *RTSAttr = D->getAttr<ReturnTypestateAttr>()) {
1240  const CXXRecordDecl *RD = ReturnType->getAsCXXRecordDecl();
1241  if (!RD || !RD->hasAttr<ConsumableAttr>()) {
1242  // FIXME: This should be removed when template instantiation propagates
1243  // attributes at template specialization definition, not
1244  // declaration. When it is removed the test needs to be enabled
1245  // in SemaDeclAttr.cpp.
1246  WarningsHandler.warnReturnTypestateForUnconsumableType(
1247  RTSAttr->getLocation(), ReturnType.getAsString());
1248  ExpectedReturnState = CS_None;
1249  } else
1250  ExpectedReturnState = mapReturnTypestateAttrState(RTSAttr);
1251  } else if (isConsumableType(ReturnType)) {
1252  if (isAutoCastType(ReturnType)) // We can auto-cast the state to the
1253  ExpectedReturnState = CS_None; // expected state.
1254  else
1255  ExpectedReturnState = mapConsumableAttrState(ReturnType);
1256  }
1257  else
1258  ExpectedReturnState = CS_None;
1259 }
1260 
1261 bool ConsumedAnalyzer::splitState(const CFGBlock *CurrBlock,
1262  const ConsumedStmtVisitor &Visitor) {
1263 
1264  std::unique_ptr<ConsumedStateMap> FalseStates(
1265  new ConsumedStateMap(*CurrStates));
1266  PropagationInfo PInfo;
1267 
1268  if (const IfStmt *IfNode =
1269  dyn_cast_or_null<IfStmt>(CurrBlock->getTerminator().getStmt())) {
1270 
1271  const Expr *Cond = IfNode->getCond();
1272 
1273  PInfo = Visitor.getInfo(Cond);
1274  if (!PInfo.isValid() && isa<BinaryOperator>(Cond))
1275  PInfo = Visitor.getInfo(cast<BinaryOperator>(Cond)->getRHS());
1276 
1277  if (PInfo.isVarTest()) {
1278  CurrStates->setSource(Cond);
1279  FalseStates->setSource(Cond);
1280  splitVarStateForIf(IfNode, PInfo.getVarTest(), CurrStates.get(),
1281  FalseStates.get());
1282 
1283  } else if (PInfo.isBinTest()) {
1284  CurrStates->setSource(PInfo.testSourceNode());
1285  FalseStates->setSource(PInfo.testSourceNode());
1286  splitVarStateForIfBinOp(PInfo, CurrStates.get(), FalseStates.get());
1287 
1288  } else {
1289  return false;
1290  }
1291 
1292  } else if (const BinaryOperator *BinOp =
1293  dyn_cast_or_null<BinaryOperator>(CurrBlock->getTerminator().getStmt())) {
1294 
1295  PInfo = Visitor.getInfo(BinOp->getLHS());
1296  if (!PInfo.isVarTest()) {
1297  if ((BinOp = dyn_cast_or_null<BinaryOperator>(BinOp->getLHS()))) {
1298  PInfo = Visitor.getInfo(BinOp->getRHS());
1299 
1300  if (!PInfo.isVarTest())
1301  return false;
1302 
1303  } else {
1304  return false;
1305  }
1306  }
1307 
1308  CurrStates->setSource(BinOp);
1309  FalseStates->setSource(BinOp);
1310 
1311  const VarTestResult &Test = PInfo.getVarTest();
1312  ConsumedState VarState = CurrStates->getState(Test.Var);
1313 
1314  if (BinOp->getOpcode() == BO_LAnd) {
1315  if (VarState == CS_Unknown)
1316  CurrStates->setState(Test.Var, Test.TestsFor);
1317  else if (VarState == invertConsumedUnconsumed(Test.TestsFor))
1318  CurrStates->markUnreachable();
1319 
1320  } else if (BinOp->getOpcode() == BO_LOr) {
1321  if (VarState == CS_Unknown)
1322  FalseStates->setState(Test.Var,
1323  invertConsumedUnconsumed(Test.TestsFor));
1324  else if (VarState == Test.TestsFor)
1325  FalseStates->markUnreachable();
1326  }
1327 
1328  } else {
1329  return false;
1330  }
1331 
1332  CFGBlock::const_succ_iterator SI = CurrBlock->succ_begin();
1333 
1334  if (*SI)
1335  BlockInfo.addInfo(*SI, std::move(CurrStates));
1336  else
1337  CurrStates = nullptr;
1338 
1339  if (*++SI)
1340  BlockInfo.addInfo(*SI, std::move(FalseStates));
1341 
1342  return true;
1343 }
1344 
1346  const FunctionDecl *D = dyn_cast_or_null<FunctionDecl>(AC.getDecl());
1347  if (!D)
1348  return;
1349 
1350  CFG *CFGraph = AC.getCFG();
1351  if (!CFGraph)
1352  return;
1353 
1354  determineExpectedReturnState(AC, D);
1355 
1356  PostOrderCFGView *SortedGraph = AC.getAnalysis<PostOrderCFGView>();
1357  // AC.getCFG()->viewCFG(LangOptions());
1358 
1359  BlockInfo = ConsumedBlockInfo(CFGraph->getNumBlockIDs(), SortedGraph);
1360 
1361  CurrStates = llvm::make_unique<ConsumedStateMap>();
1362  ConsumedStmtVisitor Visitor(AC, *this, CurrStates.get());
1363 
1364  // Add all trackable parameters to the state map.
1365  for (const auto *PI : D->parameters())
1366  Visitor.VisitParmVarDecl(PI);
1367 
1368  // Visit all of the function's basic blocks.
1369  for (const auto *CurrBlock : *SortedGraph) {
1370  if (!CurrStates)
1371  CurrStates = BlockInfo.getInfo(CurrBlock);
1372 
1373  if (!CurrStates) {
1374  continue;
1375 
1376  } else if (!CurrStates->isReachable()) {
1377  CurrStates = nullptr;
1378  continue;
1379  }
1380 
1381  Visitor.reset(CurrStates.get());
1382 
1383  // Visit all of the basic block's statements.
1384  for (const auto &B : *CurrBlock) {
1385  switch (B.getKind()) {
1386  case CFGElement::Statement:
1387  Visitor.Visit(B.castAs<CFGStmt>().getStmt());
1388  break;
1389 
1391  const CFGTemporaryDtor &DTor = B.castAs<CFGTemporaryDtor>();
1392  const CXXBindTemporaryExpr *BTE = DTor.getBindTemporaryExpr();
1393 
1394  Visitor.checkCallability(PropagationInfo(BTE),
1395  DTor.getDestructorDecl(AC.getASTContext()),
1396  BTE->getExprLoc());
1397  CurrStates->remove(BTE);
1398  break;
1399  }
1400 
1402  const CFGAutomaticObjDtor &DTor = B.castAs<CFGAutomaticObjDtor>();
1403  SourceLocation Loc = DTor.getTriggerStmt()->getLocEnd();
1404  const VarDecl *Var = DTor.getVarDecl();
1405 
1406  Visitor.checkCallability(PropagationInfo(Var),
1407  DTor.getDestructorDecl(AC.getASTContext()),
1408  Loc);
1409  break;
1410  }
1411 
1412  default:
1413  break;
1414  }
1415  }
1416 
1417  // TODO: Handle other forms of branching with precision, including while-
1418  // and for-loops. (Deferred)
1419  if (!splitState(CurrBlock, Visitor)) {
1420  CurrStates->setSource(nullptr);
1421 
1422  if (CurrBlock->succ_size() > 1 ||
1423  (CurrBlock->succ_size() == 1 &&
1424  (*CurrBlock->succ_begin())->pred_size() > 1)) {
1425 
1426  auto *RawState = CurrStates.get();
1427 
1428  for (CFGBlock::const_succ_iterator SI = CurrBlock->succ_begin(),
1429  SE = CurrBlock->succ_end(); SI != SE; ++SI) {
1430 
1431  if (*SI == nullptr) continue;
1432 
1433  if (BlockInfo.isBackEdge(CurrBlock, *SI)) {
1434  BlockInfo.borrowInfo(*SI)->intersectAtLoopHead(
1435  *SI, CurrBlock, RawState, WarningsHandler);
1436 
1437  if (BlockInfo.allBackEdgesVisited(CurrBlock, *SI))
1438  BlockInfo.discardInfo(*SI);
1439  } else {
1440  BlockInfo.addInfo(*SI, RawState, CurrStates);
1441  }
1442  }
1443 
1444  CurrStates = nullptr;
1445  }
1446  }
1447 
1448  if (CurrBlock == &AC.getCFG()->getExit() &&
1449  D->getCallResultType()->isVoidType())
1450  CurrStates->checkParamsForReturnTypestate(D->getLocation(),
1451  WarningsHandler);
1452  } // End of block iterator.
1453 
1454  // Delete the last existing state map.
1455  CurrStates = nullptr;
1456 
1457  WarningsHandler.emitDiagnostics();
1458 }
1459 }} // end namespace clang::consumed
A call to an overloaded operator written using operator syntax.
Definition: ExprCXX.h:52
Defines the clang::ASTContext interface.
FunctionDecl - An instance of this class is created to represent a function declaration or definition...
Definition: Decl.h:1561
ASTContext & getASTContext() const
pred_iterator pred_end()
Definition: CFG.h:532
A (possibly-)qualified type.
Definition: Type.h:598
Expr * getArg(unsigned Arg)
getArg - Return the specified argument.
Definition: Expr.h:2217
QualType getCallResultType() const
Determine the type of an expression that calls this function.
Definition: Decl.h:2045
ConstStmtVisitor - This class implements a simple visitor for Stmt subclasses.
Definition: StmtVisitor.h:187
void VisitCastExpr(const CastExpr *Cast)
Definition: Consumed.cpp:765
succ_iterator succ_begin()
Definition: CFG.h:541
IfStmt - This represents an if/then/else.
Definition: Stmt.h:881
Expr * GetTemporaryExpr() const
Retrieve the temporary-generating subexpression whose value will be materialized into a glvalue...
Definition: ExprCXX.h:4003
C Language Family Type Representation.
void addInfo(const CFGBlock *Block, ConsumedStateMap *StateMap, std::unique_ptr< ConsumedStateMap > &OwnedStateMap)
Definition: Consumed.cpp:1047
virtual void warnParamReturnTypestateMismatch(SourceLocation Loc, StringRef VariableName, StringRef ExpectedState, StringRef ObservedState)
Warn about parameter typestate mismatches upon return.
Definition: Consumed.h:71
std::string getAsString() const
Definition: Type.h:924
void VisitUnaryOperator(const UnaryOperator *UOp)
Definition: Consumed.cpp:912
bool isCopyConstructor(unsigned &TypeQuals) const
Whether this constructor is a copy constructor (C++ [class.copy]p2, which can be used to copy the cla...
Definition: DeclCXX.cpp:1872
bool handleCall(const CallExpr *Call, const Expr *ObjArg, const FunctionDecl *FunD)
Definition: Consumed.cpp:614
const Expr * getInit() const
Definition: Decl.h:1139
Represents a call to a C++ constructor.
Definition: ExprCXX.h:1162
void run(AnalysisDeclContext &AC)
Check a function's CFG for consumed violations.
Definition: Consumed.cpp:1345
SourceLocation getLocStart() const LLVM_READONLY
Definition: Stmt.h:1396
Represents a C++ constructor within a class.
Definition: DeclCXX.h:2187
Represents a prvalue temporary that is written into memory so that a reference can bind to it...
Definition: ExprCXX.h:3962
static ConsumedState testsFor(const FunctionDecl *FunDecl)
Definition: Consumed.cpp:264
void setState(const VarDecl *Var, ConsumedState State)
Set the consumed state of a given variable.
Definition: Consumed.cpp:1210
VarDecl - An instance of this class is created to represent a variable declaration or definition...
Definition: Decl.h:768
SourceLocation getReturnLoc() const
Definition: Stmt.h:1385
void VisitCXXMemberCallExpr(const CXXMemberCallExpr *Call)
Definition: Consumed.cpp:813
const VarTestResult & getLTest() const
Definition: Consumed.cpp:368
unsigned succ_size() const
Definition: CFG.h:551
QualType getThisType(ASTContext &C) const
Returns the type of the this pointer.
Definition: DeclCXX.cpp:1672
Expr * IgnoreImplicit() LLVM_READONLY
IgnoreImplicit - Skip past any implicit AST nodes which might surround this expression.
Definition: Expr.h:724
const BinaryOperator * testSourceNode() const
Definition: Consumed.cpp:406
void remove(const CXXBindTemporaryExpr *Tmp)
Remove the temporary value from our state map.
Definition: Consumed.cpp:1219
ParmVarDecl - Represents a parameter to a function.
Definition: Decl.h:1377
Defines the clang::Expr interface and subclasses for C++ expressions.
bool isVoidType() const
Definition: Type.h:5680
PropagationInfo(const VarTestResult &VarTest)
Definition: Consumed.cpp:318
PropagationInfo(const VarDecl *Var)
Definition: Consumed.cpp:354
void intersectAtLoopHead(const CFGBlock *LoopHead, const CFGBlock *LoopBack, const ConsumedStateMap *LoopBackStates, ConsumedWarningsHandlerBase &WarningsHandler)
Definition: Consumed.cpp:1183
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:92
LineState State
ConsumedStmtVisitor(AnalysisDeclContext &AC, ConsumedAnalyzer &Analyzer, ConsumedStateMap *StateMap)
Definition: Consumed.cpp:513
bool isReferenceType() const
Definition: Type.h:5491
AnalysisDeclContext contains the context data for the function or method under analysis.
CFGAutomaticObjDtor - Represents C++ object destructor implicitly generated for automatic object or t...
Definition: CFG.h:194
Expr * getImplicitObjectArgument() const
Retrieves the implicit object argument for the member call.
Definition: ExprCXX.cpp:459
const CXXRecordDecl * getPointeeCXXRecordDecl() const
If this is a pointer or reference to a RecordType, return the CXXRecordDecl that that type refers to...
Definition: Type.cpp:1513
PropagationInfo(const BinaryOperator *Source, EffectiveOp EOp, const VarDecl *LVar, ConsumedState LTestsFor, const VarDecl *RVar, ConsumedState RTestsFor)
Definition: Consumed.cpp:338
static void splitVarStateForIf(const IfStmt *IfNode, const VarTestResult &Test, ConsumedStateMap *ThenStates, ConsumedStateMap *ElseStates)
Definition: Consumed.cpp:955
PropagationInfo invertTest() const
Definition: Consumed.cpp:426
T castAs() const
Convert to the specified CFGElement type, asserting that this CFGElement is of the desired type...
Definition: CFG.h:87
bool isMoveConstructor(unsigned &TypeQuals) const
Determine whether this constructor is a move constructor (C++11 [class.copy]p3), which can be used to...
Definition: DeclCXX.cpp:1877
PropagationInfo(const CXXBindTemporaryExpr *Tmp)
Definition: Consumed.cpp:355
static ConsumedState mapReturnTypestateAttrState(const ReturnTypestateAttr *RTSAttr)
Definition: Consumed.cpp:223
Expr * getSubExpr()
Definition: Expr.h:2684
void markUnreachable()
Mark the block as unreachable.
Definition: Consumed.cpp:1204
const VarTestResult & getVarTest() const
Definition: Consumed.cpp:363
const CXXBindTemporaryExpr * getBindTemporaryExpr() const
Definition: CFG.h:285
Expr * getLHS() const
Definition: Expr.h:2943
ConsumedState getState(const VarDecl *Var) const
Get the consumed state of a given variable.
Definition: Consumed.cpp:1145
const VarTestResult & getRTest() const
Definition: Consumed.cpp:373
void checkParamsForReturnTypestate(SourceLocation BlameLoc, ConsumedWarningsHandlerBase &WarningsHandler) const
Warn if any of the parameters being tracked are not in the state they were declared to be in upon ret...
Definition: Consumed.cpp:1121
bool allBackEdgesVisited(const CFGBlock *CurrBlock, const CFGBlock *TargetBlock)
Definition: Consumed.cpp:1032
uint32_t Offset
Definition: CacheTokens.cpp:44
const VarDecl * getVarDecl() const
Definition: CFG.h:199
const CXXBindTemporaryExpr * Tmp
Definition: Consumed.cpp:311
unsigned pred_size() const
Definition: CFG.h:554
T * getAnalysis()
Return the specified analysis object, lazily running the analysis if necessary.
void VisitCXXBindTemporaryExpr(const CXXBindTemporaryExpr *Temp)
Definition: Consumed.cpp:769
A builtin binary operation expression such as "x + y" or "x <= y".
Definition: Expr.h:2897
std::unique_ptr< ConsumedStateMap > getInfo(const CFGBlock *Block)
Definition: Consumed.cpp:1089
std::string getNameAsString() const
getNameAsString - Get a human-readable name for the declaration, even if it is one of the special kin...
Definition: Decl.h:252
CastExpr - Base class for type casts, including both implicit casts (ImplicitCastExpr) and explicit c...
Definition: Expr.h:2632
Represents binding an expression to a temporary.
Definition: ExprCXX.h:1119
const Decl * getDecl() const
const Stmt * getTriggerStmt() const
Definition: CFG.h:204
QualType getType() const
Definition: Decl.h:599
reverse_iterator rend()
Definition: CFG.h:511
static bool isConsumableType(const QualType &QT)
Definition: Consumed.cpp:141
RetTy Visit(PTR(Stmt) S)
Definition: StmtVisitor.h:40
static void splitVarStateForIfBinOp(const PropagationInfo &PInfo, ConsumedStateMap *ThenStates, ConsumedStateMap *ElseStates)
Definition: Consumed.cpp:972
CXXMethodDecl * getMethodDecl() const
Retrieves the declaration of the called method.
Definition: ExprCXX.cpp:471
CFGBlock - Represents a single basic block in a source-level CFG.
Definition: CFG.h:353
QualType getPointeeType() const
If this is a pointer, ObjC object pointer, or block pointer, this returns the respective pointee...
Definition: Type.cpp:415
virtual void warnLoopStateMismatch(SourceLocation Loc, StringRef VariableName)
Warn that a variable's state doesn't match at the entry and exit of a loop.
Definition: Consumed.h:59
static bool isPointerOrRef(QualType ParamType)
Definition: Consumed.cpp:188
bool isBackEdge(const CFGBlock *From, const CFGBlock *To)
Definition: Consumed.cpp:1097
void clearTemporaries()
Clear the TmpMap.
Definition: Consumed.cpp:1141
Expr - This represents one expression.
Definition: Expr.h:105
static StringRef stateToString(ConsumedState State)
Definition: Consumed.cpp:247
CFG - Represents a source-level, intra-procedural CFG that represents the control-flow of a Stmt...
Definition: CFG.h:721
const CXXBindTemporaryExpr * getTmp() const
Definition: Consumed.cpp:383
Defines an enumeration for C++ overloaded operators.
const ParmVarDecl * getParamDecl(unsigned i) const
Definition: Decl.h:2011
void VisitDeclRefExpr(const DeclRefExpr *DeclRef)
Definition: Consumed.cpp:846
PropagationInfo(ConsumedState State)
Definition: Consumed.cpp:351
AdjacentBlocks::const_iterator const_pred_iterator
Definition: CFG.h:522
Expr * getSubExpr() const
Definition: Expr.h:1695
unsigned getBlockID() const
Definition: CFG.h:638
ReturnStmt - This represents a return, optionally of an expression: return; return 4;...
Definition: Stmt.h:1366
UnaryOperator - This represents the unary-expression's (except sizeof and alignof), the postinc/postdec operators from postfix-expression, and various extensions.
Definition: Expr.h:1668
ValueDecl * getDecl()
Definition: Expr.h:1017
const ConsumedState & getState() const
Definition: Consumed.cpp:358
bool operator!=(const ConsumedStateMap *Other) const
Tests to see if there is a mismatch in the states stored in two maps.
Definition: Consumed.cpp:1223
void checkCallability(const PropagationInfo &PInfo, const FunctionDecl *FunDecl, SourceLocation BlameLoc)
Definition: Consumed.cpp:580
reverse_iterator rbegin()
Definition: CFG.h:510
void VisitVarDecl(const VarDecl *Var)
Definition: Consumed.cpp:932
void VisitReturnStmt(const ReturnStmt *Ret)
Definition: Consumed.cpp:892
void VisitDeclStmt(const DeclStmt *DelcS)
Definition: Consumed.cpp:852
const VarDecl * getVar() const
Definition: Consumed.cpp:378
static ConsumedState mapConsumableAttrState(const QualType QT)
Definition: Consumed.cpp:192
CFGTerminator getTerminator()
Definition: CFG.h:622
Encodes a location in the source.
unsigned getNumParams() const
getNumParams - Return the number of parameters this function must have based on its FunctionType...
Definition: Decl.cpp:2742
const TemplateArgument * iterator
Definition: Type.h:4233
bool isValid() const
Return true if this is a valid SourceLocation object.
bool isSingleDecl() const
isSingleDecl - This method returns true if this DeclStmt refers to a single Decl. ...
Definition: Stmt.h:457
Represents a call to a member function that may be written either with member call syntax (e...
Definition: ExprCXX.h:121
DeclStmt - Adaptor class for mixing declarations with statements and expressions. ...
Definition: Stmt.h:443
Represents a static or instance method of a struct/union/class.
Definition: DeclCXX.h:1736
const Stmt * getStmt() const
Definition: CFG.h:119
static bool isTestingFunction(const FunctionDecl *FunDecl)
Definition: Consumed.cpp:184
static bool isKnownState(ConsumedState State)
Definition: Consumed.cpp:168
ArrayRef< ParmVarDecl * > parameters() const
Definition: Decl.h:1989
PropagationInfo(const BinaryOperator *Source, EffectiveOp EOp, const VarTestResult &LTest, const VarTestResult &RTest)
Definition: Consumed.cpp:328
void VisitMemberExpr(const MemberExpr *MExpr)
Definition: Consumed.cpp:868
static bool isSetOnReadPtrType(const QualType &QT)
Definition: Consumed.cpp:161
const CXXDestructorDecl * getDestructorDecl(ASTContext &astContext) const
Definition: CFG.cpp:3895
void VisitCXXOperatorCallExpr(const CXXOperatorCallExpr *Call)
Definition: Consumed.cpp:824
AdjacentBlocks::const_iterator const_succ_iterator
Definition: CFG.h:527
Opcode getOpcode() const
Definition: Expr.h:1692
const Decl * getSingleDecl() const
Definition: Stmt.h:461
SourceLocation getExprLoc() const LLVM_READONLY
getExprLoc - Return the preferred location for the arrow when diagnosing a problem with a generic exp...
Definition: Expr.cpp:193
pred_iterator pred_begin()
Definition: CFG.h:531
void reset(ConsumedStateMap *NewStateMap)
Definition: Consumed.cpp:526
FunctionDecl * getDirectCallee()
If the callee is a FunctionDecl, return it. Otherwise return 0.
Definition: Expr.cpp:1209
static void setStateForVarOrTmp(ConsumedStateMap *StateMap, const PropagationInfo &PInfo, ConsumedState State)
Definition: Consumed.cpp:445
detail::InMemoryDirectory::const_iterator E
A class that handles the analysis of uniqueness violations.
Definition: Consumed.h:238
const Expr * getRetValue() const
Definition: Stmt.cpp:899
unsigned getNumArgs() const
getNumArgs - Return the number of actual arguments to this call.
Definition: Expr.h:2205
Stmt * getStmt()
Definition: CFG.h:310
bool isRValueReferenceType() const
Definition: Type.h:5497
static bool isRValueRef(QualType ParamType)
Definition: Consumed.cpp:180
static const TypeInfo & getInfo(unsigned id)
Definition: Types.cpp:34
void VisitParmVarDecl(const ParmVarDecl *Param)
Definition: Consumed.cpp:873
ConsumedStateMap * borrowInfo(const CFGBlock *Block)
Definition: Consumed.cpp:1077
PropagationInfo(const VarDecl *Var, ConsumedState TestsFor)
Definition: Consumed.cpp:321
Expr * getArg(unsigned Arg)
Return the specified argument.
Definition: ExprCXX.h:1288
CXXConstructorDecl * getConstructor() const
Get the constructor that this expression will (ultimately) call.
Definition: ExprCXX.h:1225
decl_range decls()
Definition: Stmt.h:491
CXXRecordDecl * getAsCXXRecordDecl() const
Retrieves the CXXRecordDecl that this type refers to, either because the type is a RecordType or beca...
Definition: Type.cpp:1528
bool isDefaultConstructor() const
Whether this constructor is a default constructor (C++ [class.ctor]p5), which can be used to default-...
Definition: DeclCXX.cpp:1863
void discardInfo(const CFGBlock *Block)
Definition: Consumed.cpp:1084
Expr * getBase() const
Definition: Expr.h:2405
Defines the C++ Decl subclasses, other than those for templates (found in DeclTemplate.h) and friends (in DeclFriend.h).
static SourceLocation getFirstStmtLoc(const CFGBlock *Block)
Definition: Consumed.cpp:57
MemberExpr - [C99 6.5.2.3] Structure and Union Members.
Definition: Expr.h:2315
OverloadedOperatorKind getOperator() const
Returns the kind of overloaded operator that this expression refers to.
Definition: ExprCXX.h:77
Defines the clang::SourceLocation class and associated facilities.
void VisitCallExpr(const CallExpr *Call)
Definition: Consumed.cpp:748
void VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *Temp)
Definition: Consumed.cpp:862
Represents a C++ struct/union/class.
Definition: DeclCXX.h:263
static bool isAutoCastType(const QualType &QT)
Definition: Consumed.cpp:151
Opcode getOpcode() const
Definition: Expr.h:2940
void VisitBinaryOperator(const BinaryOperator *BinOp)
Definition: Consumed.cpp:706
CFGElement - Represents a top-level expression in a basic block.
Definition: CFG.h:53
bool isBackEdgeTarget(const CFGBlock *Block)
Definition: Consumed.cpp:1104
CallExpr - Represents a function call (C99 6.5.2.2, C++ [expr.call]).
Definition: Expr.h:2148
Expr * getRHS() const
Definition: Expr.h:2945
static ConsumedState mapParamTypestateAttrState(const ParamTypestateAttr *PTAttr)
Definition: Consumed.cpp:210
static bool isCallableInState(const CallableWhenAttr *CWAttr, ConsumedState State)
Definition: Consumed.cpp:113
A reference to a declared variable, function, enum, etc.
Definition: Expr.h:932
void VisitCXXConstructExpr(const CXXConstructExpr *Call)
Definition: Consumed.cpp:780
const Expr * getSubExpr() const
Definition: ExprCXX.h:1143
static SourceLocation getLastStmtLoc(const CFGBlock *Block)
Definition: Consumed.cpp:72
static ConsumedState mapSetTypestateAttrState(const SetTypestateAttr *STAttr)
Definition: Consumed.cpp:235
PropagationInfo getInfo(const Expr *StmtNode) const
Definition: Consumed.cpp:517
bool isConstQualified() const
Determine whether this type is const-qualified.
Definition: Type.h:5318
unsigned getNumBlockIDs() const
getNumBlockIDs - Returns the total number of BlockIDs allocated (which start at 0).
Definition: CFG.h:931
CFGTemporaryDtor - Represents C++ object destructor implicitly generated at the end of full expressio...
Definition: CFG.h:280
static ConsumedState invertConsumedUnconsumed(ConsumedState State)
Definition: Consumed.cpp:99
ConsumedState getAsState(const ConsumedStateMap *StateMap) const
Definition: Consumed.cpp:388
EffectiveOp testEffectiveOp() const
Definition: Consumed.cpp:401
Expr * IgnoreParens() LLVM_READONLY
IgnoreParens - Ignore parentheses.
Definition: Expr.cpp:2295
void intersect(const ConsumedStateMap &Other)
Merge this state map with another map.
Definition: Consumed.cpp:1164
bool isPointerType() const
Definition: Type.h:5482
CFGBlock & getExit()
Definition: CFG.h:864
bool hasInit() const
Definition: Decl.cpp:2040