From: DeLesley Hutchins Date: Fri, 21 Oct 2011 18:10:14 +0000 (+0000) Subject: Thread safety analysis refactoring: invalid lock expressions. X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=f1ac63702143d84db778d32eb185a77fc97db5f5;p=clang Thread safety analysis refactoring: invalid lock expressions. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@142666 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td index 38ba954d35..41581ae49c 100644 --- a/include/clang/Basic/DiagnosticSemaKinds.td +++ b/include/clang/Basic/DiagnosticSemaKinds.td @@ -1575,7 +1575,7 @@ def warn_fun_excludes_mutex : Warning< "cannot call function '%0' while mutex '%1' is locked">, InGroup, DefaultIgnore; def warn_cannot_resolve_lock : Warning< - "cannot resolve lock expression to a specific lockable object">, + "cannot resolve lock expression">, InGroup, DefaultIgnore; diff --git a/lib/Analysis/ThreadSafety.cpp b/lib/Analysis/ThreadSafety.cpp index 5f03b5832b..5b813ff2ea 100644 --- a/lib/Analysis/ThreadSafety.cpp +++ b/lib/Analysis/ThreadSafety.cpp @@ -164,6 +164,11 @@ class MutexID { /// ensure that the original expression is a valid mutex expression. void buildMutexID(Expr *Exp, Expr *Parent, int NumArgs, const NamedDecl **FunArgDecls, Expr **FunArgs) { + if (!Exp) { + DeclSeq.clear(); + return; + } + if (DeclRefExpr *DRE = dyn_cast(Exp)) { if (FunArgDecls) { // Substitute call arguments for references to function parameters @@ -204,6 +209,7 @@ class MutexID { Expr **FunArgs = 0; SmallVector FunArgDecls; + // If we are processing a raw attribute expression, with no substitutions. if (DeclExp == 0) { buildMutexID(MutexExp, 0, 0, 0, 0); return; @@ -254,6 +260,18 @@ public: return !DeclSeq.empty(); } + /// Issue a warning about an invalid lock expression + static void warnInvalidLock(ThreadSafetyHandler &Handler, Expr* MutexExp, + Expr *DeclExp, const NamedDecl* D) { + SourceLocation Loc; + if (DeclExp) + Loc = DeclExp->getExprLoc(); + + // FIXME: add a note about the attribute location in MutexExp or D + if (Loc.isValid()) + Handler.handleInvalidLockExp(Loc); + } + bool operator==(const MutexID &other) const { return DeclSeq == other.DeclSeq; } @@ -333,6 +351,8 @@ typedef llvm::ImmutableMap Lockset; /// output error messages related to missing locks. /// FIXME: In future, we may be able to not inherit from a visitor. class BuildLockset : public StmtVisitor { + friend class ThreadSafetyAnalyzer; + ThreadSafetyHandler &Handler; Lockset LSet; Lockset::Factory &LocksetFactory; @@ -343,6 +363,8 @@ class BuildLockset : public StmtVisitor { template void addLocksToSet(LockKind LK, AttrType *Attr, Expr *Exp, NamedDecl *D); + void removeLocksFromSet(UnlockFunctionAttr *Attr, + Expr *Exp, NamedDecl* FunDecl); const ValueDecl *getValueDecl(Expr *Exp); void warnIfMutexNotHeld (const NamedDecl *D, Expr *Exp, AccessKind AK, @@ -407,7 +429,8 @@ void BuildLockset::addLock(SourceLocation LockLoc, MutexID &Mutex, // FIXME: Don't always warn when we have support for reentrant locks. if (locksetContains(Mutex)) Handler.handleDoubleLock(Mutex.getName(), LockLoc); - LSet = LocksetFactory.add(LSet, Mutex, NewLock); + else + LSet = LocksetFactory.add(LSet, Mutex, NewLock); } /// \brief Remove a lock from the lockset, warning if the lock is not there. @@ -417,8 +440,8 @@ void BuildLockset::removeLock(SourceLocation UnlockLoc, MutexID &Mutex) { Lockset NewLSet = LocksetFactory.remove(LSet, Mutex); if(NewLSet == LSet) Handler.handleUnmatchedUnlock(Mutex.getName(), UnlockLoc); - - LSet = NewLSet; + else + LSet = NewLSet; } /// \brief This function, parameterized by an attribute type, is used to add a @@ -432,10 +455,9 @@ void BuildLockset::addLocksToSet(LockKind LK, AttrType *Attr, if (Attr->args_size() == 0) { // The mutex held is the "this" object. - MutexID Mutex(0, Exp, FunDecl); if (!Mutex.isValid()) - Handler.handleInvalidLockExp(Exp->getExprLoc()); + MutexID::warnInvalidLock(Handler, 0, Exp, FunDecl); else addLock(ExpLocation, Mutex, LK); return; @@ -444,12 +466,39 @@ void BuildLockset::addLocksToSet(LockKind LK, AttrType *Attr, for (iterator_type I=Attr->args_begin(), E=Attr->args_end(); I != E; ++I) { MutexID Mutex(*I, Exp, FunDecl); if (!Mutex.isValid()) - Handler.handleInvalidLockExp(Exp->getExprLoc()); + MutexID::warnInvalidLock(Handler, *I, Exp, FunDecl); else addLock(ExpLocation, Mutex, LK); } } +/// \brief This function removes a set of locks specified as attribute +/// arguments from the lockset. +void BuildLockset::removeLocksFromSet(UnlockFunctionAttr *Attr, + Expr *Exp, NamedDecl* FunDecl) { + SourceLocation ExpLocation; + if (Exp) ExpLocation = Exp->getExprLoc(); + + if (Attr->args_size() == 0) { + // The mutex held is the "this" object. + MutexID Mu(0, Exp, FunDecl); + if (!Mu.isValid()) + MutexID::warnInvalidLock(Handler, 0, Exp, FunDecl); + else + removeLock(ExpLocation, Mu); + return; + } + + for (UnlockFunctionAttr::args_iterator I = Attr->args_begin(), + E = Attr->args_end(); I != E; ++I) { + MutexID Mutex(*I, Exp, FunDecl); + if (!Mutex.isValid()) + MutexID::warnInvalidLock(Handler, *I, Exp, FunDecl); + else + removeLock(ExpLocation, Mutex); + } +} + /// \brief Gets the value decl pointer from DeclRefExprs or MemberExprs const ValueDecl *BuildLockset::getValueDecl(Expr *Exp) { if (const DeclRefExpr *DR = dyn_cast(Exp)) @@ -470,7 +519,7 @@ void BuildLockset::warnIfMutexNotHeld(const NamedDecl *D, Expr *Exp, MutexID Mutex(MutexExp, Exp, D); if (!Mutex.isValid()) - Handler.handleInvalidLockExp(MutexExp->getExprLoc()); + MutexID::warnInvalidLock(Handler, MutexExp, Exp, D); else if (!locksetContainsAtLeast(Mutex, LK)) Handler.handleMutexNotHeld(D, POK, Mutex.getName(), LK, Exp->getExprLoc()); } @@ -533,8 +582,6 @@ void BuildLockset::checkAccess(Expr *Exp, AccessKind AK) { /// FIXME: Do not flag an error for member variables accessed in constructors/ /// destructors void BuildLockset::handleCall(Expr *Exp, NamedDecl *D) { - SourceLocation ExpLocation = Exp->getExprLoc(); - AttrVec &ArgAttrs = D->getAttrs(); for(unsigned i = 0; i < ArgAttrs.size(); ++i) { Attr *Attr = ArgAttrs[i]; @@ -559,24 +606,7 @@ void BuildLockset::handleCall(Expr *Exp, NamedDecl *D) { // mutexes from the lockset, and flag a warning if they are not there. case attr::UnlockFunction: { UnlockFunctionAttr *UFAttr = cast(Attr); - - if (UFAttr->args_size() == 0) { // The lock held is the "this" object. - MutexID Mu(0, Exp, D); - if (!Mu.isValid()) - Handler.handleInvalidLockExp(Exp->getExprLoc()); - else - removeLock(ExpLocation, Mu); - break; - } - - for (UnlockFunctionAttr::args_iterator I = UFAttr->args_begin(), - E = UFAttr->args_end(); I != E; ++I) { - MutexID Mutex(*I, Exp, D); - if (!Mutex.isValid()) - Handler.handleInvalidLockExp(Exp->getExprLoc()); - else - removeLock(ExpLocation, Mutex); - } + removeLocksFromSet(UFAttr, Exp, D); break; } @@ -605,10 +635,10 @@ void BuildLockset::handleCall(Expr *Exp, NamedDecl *D) { E = LEAttr->args_end(); I != E; ++I) { MutexID Mutex(*I, Exp, D); if (!Mutex.isValid()) - Handler.handleInvalidLockExp((*I)->getExprLoc()); + MutexID::warnInvalidLock(Handler, *I, Exp, D); else if (locksetContains(Mutex)) Handler.handleFunExcludesLock(D->getName(), Mutex.getName(), - ExpLocation); + Exp->getExprLoc()); } break; } @@ -741,7 +771,7 @@ Lockset ThreadSafetyAnalyzer::addLock(Lockset &LSet, Expr *MutexExp, LockKind LK, SourceLocation Loc) { MutexID Mutex(MutexExp, 0, D); if (!Mutex.isValid()) { - Handler.handleInvalidLockExp(MutexExp->getExprLoc()); + MutexID::warnInvalidLock(Handler, MutexExp, 0, D); return LSet; } LockData NewLock(Loc, LK); diff --git a/lib/Sema/AnalysisBasedWarnings.cpp b/lib/Sema/AnalysisBasedWarnings.cpp index a8ee0b8617..bd34dece6e 100644 --- a/lib/Sema/AnalysisBasedWarnings.cpp +++ b/lib/Sema/AnalysisBasedWarnings.cpp @@ -648,15 +648,21 @@ struct SortDiagBySourceLocation { class ThreadSafetyReporter : public clang::thread_safety::ThreadSafetyHandler { Sema &S; DiagList Warnings; + SourceLocation FunLocation; // Helper functions void warnLockMismatch(unsigned DiagID, Name LockName, SourceLocation Loc) { + // Gracefully handle rare cases when the analysis can't get a more + // precise source location. + if (!Loc.isValid()) + Loc = FunLocation; PartialDiagnostic Warning = S.PDiag(DiagID) << LockName; Warnings.push_back(DelayedDiag(Loc, Warning)); } public: - ThreadSafetyReporter(Sema &S) : S(S) {} + ThreadSafetyReporter(Sema &S, SourceLocation FL) + : S(S), FunLocation(FL) {} /// \brief Emit all buffered diagnostics in order of sourcelocation. /// We need to output diagnostics produced while iterating through @@ -913,7 +919,8 @@ AnalysisBasedWarnings::IssueWarnings(sema::AnalysisBasedWarnings::Policy P, // Check for thread safety violations if (P.enableThreadSafetyAnalysis) { - thread_safety::ThreadSafetyReporter Reporter(S); + SourceLocation FL = AC.getDecl()->getLocation(); + thread_safety::ThreadSafetyReporter Reporter(S, FL); thread_safety::runThreadSafetyAnalysis(AC, Reporter); Reporter.emitDiagnostics(); } diff --git a/test/SemaCXX/warn-thread-safety-analysis.cpp b/test/SemaCXX/warn-thread-safety-analysis.cpp index 06c013887a..14ef6d1c04 100644 --- a/test/SemaCXX/warn-thread-safety-analysis.cpp +++ b/test/SemaCXX/warn-thread-safety-analysis.cpp @@ -749,23 +749,22 @@ Mutex UPmu; // FIXME: add support for lock expressions involving arrays. Mutex mua[5]; -int x __attribute__((guarded_by(UPmu = sls_mu))); // \ - // expected-warning{{cannot resolve lock expression to a specific lockable object}} -int y __attribute__((guarded_by(mua[0]))); // \ - // expected-warning{{cannot resolve lock expression to a specific lockable object}} +int x __attribute__((guarded_by(UPmu = sls_mu))); +int y __attribute__((guarded_by(mua[0]))); void testUnparse() { - // no errors, since the lock expressions are not resolved - x = 5; - y = 5; + x = 5; // \ + // expected-warning{{cannot resolve lock expression}} + y = 5; // \ + // expected-warning{{cannot resolve lock expression}} } void testUnparse2() { mua[0].Lock(); // \ - // expected-warning{{cannot resolve lock expression to a specific lockable object}} + // expected-warning{{cannot resolve lock expression}} (&(mua[0]) + 4)->Lock(); // \ - // expected-warning{{cannot resolve lock expression to a specific lockable object}} + // expected-warning{{cannot resolve lock expression}} } @@ -1476,6 +1475,7 @@ namespace substitution_test { } // end namespace substituation_test + namespace constructor_destructor_tests { Mutex fooMu; int myVar GUARDED_BY(fooMu); @@ -1494,3 +1494,21 @@ namespace constructor_destructor_tests { } } + +namespace invalid_lock_expression_test { + +class LOCKABLE MyLockable { +public: + MyLockable() __attribute__((exclusive_lock_function)) { } + ~MyLockable() __attribute__((unlock_function)) { } +}; + +// create an empty lock expression +void foo() { + MyLockable lock; // \ + // expected-warning {{cannot resolve lock expression}} +} + +} // end namespace invalid_lock_expression_test + +