diff options
Diffstat (limited to 'compilerplugins/clang/unusedfields.cxx')
| -rw-r--r-- | compilerplugins/clang/unusedfields.cxx | 97 |
1 files changed, 79 insertions, 18 deletions
diff --git a/compilerplugins/clang/unusedfields.cxx b/compilerplugins/clang/unusedfields.cxx index 5ba6ac3c1cd6..bcb2db202cec 100644 --- a/compilerplugins/clang/unusedfields.cxx +++ b/compilerplugins/clang/unusedfields.cxx @@ -159,9 +159,10 @@ public: private: MyFieldInfo niceName(const FieldDecl*); void checkTouchedFromOutside(const FieldDecl* fieldDecl, const Expr* memberExpr); - void checkWriteOnly(const FieldDecl* fieldDecl, const Expr* memberExpr); - void checkReadOnly(const FieldDecl* fieldDecl, const Expr* memberExpr); + void checkIfReadFrom(const FieldDecl* fieldDecl, const Expr* memberExpr); + void checkIfWrittenTo(const FieldDecl* fieldDecl, const Expr* memberExpr); bool isSomeKindOfZero(const Expr* arg); + bool checkForWriteWhenUsingCollectionType(const CXXMethodDecl * calleeMethodDecl); bool IsPassedByNonConst(const FieldDecl* fieldDecl, const Stmt * child, CallerWrapper callExpr, CalleeWrapper calleeFunctionDecl); llvm::Optional<CalleeWrapper> getCallee(CallExpr const *); @@ -453,14 +454,14 @@ bool UnusedFields::VisitMemberExpr( const MemberExpr* memberExpr ) checkTouchedFromOutside(fieldDecl, memberExpr); - checkWriteOnly(fieldDecl, memberExpr); + checkIfReadFrom(fieldDecl, memberExpr); - checkReadOnly(fieldDecl, memberExpr); + checkIfWrittenTo(fieldDecl, memberExpr); return true; } -void UnusedFields::checkWriteOnly(const FieldDecl* fieldDecl, const Expr* memberExpr) +void UnusedFields::checkIfReadFrom(const FieldDecl* fieldDecl, const Expr* memberExpr) { if (insideMoveOrCopyOrCloneDeclParent || insideStreamOutputOperator) { @@ -656,15 +657,10 @@ void UnusedFields::checkWriteOnly(const FieldDecl* fieldDecl, const Expr* member if (bPotentiallyReadFrom) { readFromSet.insert(fieldInfo); - if (fieldInfo.fieldName == "nNextElementNumber") - { - parent->dump(); - memberExpr->dump(); - } } } -void UnusedFields::checkReadOnly(const FieldDecl* fieldDecl, const Expr* memberExpr) +void UnusedFields::checkIfWrittenTo(const FieldDecl* fieldDecl, const Expr* memberExpr) { if (insideMoveOrCopyOrCloneDeclParent) { @@ -749,10 +745,10 @@ void UnusedFields::checkReadOnly(const FieldDecl* fieldDecl, const Expr* memberE { // if calling a non-const operator on the field auto calleeMethodDecl = callee->getAsCXXMethodDecl(); - if (calleeMethodDecl - && operatorCallExpr->getArg(0) == child && !calleeMethodDecl->isConst()) + if (calleeMethodDecl && operatorCallExpr->getArg(0) == child) { - bPotentiallyWrittenTo = true; + if (!calleeMethodDecl->isConst()) + bPotentiallyWrittenTo = checkForWriteWhenUsingCollectionType(calleeMethodDecl); } else if (IsPassedByNonConst(fieldDecl, child, operatorCallExpr, *callee)) { @@ -773,13 +769,13 @@ void UnusedFields::checkReadOnly(const FieldDecl* fieldDecl, const Expr* memberE if (tmp->isBoundMemberFunction(compiler.getASTContext())) { tmp = dyn_cast<MemberExpr>(tmp)->getBase(); } - if (cxxMemberCallExpr->getImplicitObjectArgument() == tmp - && !calleeMethodDecl->isConst()) + if (cxxMemberCallExpr->getImplicitObjectArgument() == tmp) { - bPotentiallyWrittenTo = true; + if (!calleeMethodDecl->isConst()) + bPotentiallyWrittenTo = checkForWriteWhenUsingCollectionType(calleeMethodDecl); break; } - if (IsPassedByNonConst(fieldDecl, child, cxxMemberCallExpr, CalleeWrapper(calleeMethodDecl))) + else if (IsPassedByNonConst(fieldDecl, child, cxxMemberCallExpr, CalleeWrapper(calleeMethodDecl))) bPotentiallyWrittenTo = true; } else @@ -888,6 +884,71 @@ void UnusedFields::checkReadOnly(const FieldDecl* fieldDecl, const Expr* memberE } } +// return true if this not a collection type, or if it is a collection type, and we might be writing to it +bool UnusedFields::checkForWriteWhenUsingCollectionType(const CXXMethodDecl * calleeMethodDecl) +{ + auto const tc = loplugin::TypeCheck(calleeMethodDecl->getParent()); + bool listLike = false, setLike = false, mapLike = false, cssSequence = false; + if (tc.Class("deque").StdNamespace() + || tc.Class("list").StdNamespace() + || tc.Class("queue").StdNamespace() + || tc.Class("vector").StdNamespace()) + { + listLike = true; + } + else if (tc.Class("set").StdNamespace() + || tc.Class("unordered_set").StdNamespace()) + { + setLike = true; + } + else if (tc.Class("map").StdNamespace() + || tc.Class("unordered_map").StdNamespace()) + { + mapLike = true; + } + else if (tc.Class("Sequence").Namespace("uno").Namespace("star").Namespace("sun").Namespace("com").GlobalNamespace()) + { + cssSequence = true; + } + else + return true; + + if (calleeMethodDecl->isOverloadedOperator()) + { + auto oo = calleeMethodDecl->getOverloadedOperator(); + if (oo == OO_Equal) + return true; + // This is operator[]. We only care about things that add elements to the collection. + // if nothing modifies the size of the collection, then nothing useful + // is stored in it. + if (listLike) + return false; + return true; + } + + auto name = calleeMethodDecl->getName(); + if (listLike || setLike || mapLike) + { + if (name == "reserve" || name == "shrink_to_fit" || name == "clear" + || name == "erase" || name == "pop_back" || name == "pop_front" + || name == "front" || name == "back" || name == "data" + || name == "remove" || name == "remove_if" + || name == "unique" || name == "sort" + || name == "begin" || name == "end" + || name == "rbegin" || name == "rend" + || name == "at" || name == "find" || name == "equal_range" + || name == "lower_bound" || name == "upper_bound") + return false; + } + if (cssSequence) + { + if (name == "getArray" || name == "begin" || name == "end") + return false; + } + + return true; +} + bool UnusedFields::IsPassedByNonConst(const FieldDecl* fieldDecl, const Stmt * child, CallerWrapper callExpr, CalleeWrapper calleeFunctionDecl) { |