//===--- SemaExprObjC.cpp - Semantic Analysis for ObjC Expressions --------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file implements semantic analysis for Objective-C expressions. // //===----------------------------------------------------------------------===// #include "Sema.h" #include "Lookup.h" #include "SemaInit.h" #include "clang/AST/ASTContext.h" #include "clang/AST/DeclObjC.h" #include "clang/AST/ExprObjC.h" #include "clang/AST/TypeLoc.h" #include "llvm/ADT/SmallString.h" #include "clang/Lex/Preprocessor.h" using namespace clang; Sema::ExprResult Sema::ParseObjCStringLiteral(SourceLocation *AtLocs, ExprTy **strings, unsigned NumStrings) { StringLiteral **Strings = reinterpret_cast(strings); // Most ObjC strings are formed out of a single piece. However, we *can* // have strings formed out of multiple @ strings with multiple pptokens in // each one, e.g. @"foo" "bar" @"baz" "qux" which need to be turned into one // StringLiteral for ObjCStringLiteral to hold onto. StringLiteral *S = Strings[0]; // If we have a multi-part string, merge it all together. if (NumStrings != 1) { // Concatenate objc strings. llvm::SmallString<128> StrBuf; llvm::SmallVector StrLocs; for (unsigned i = 0; i != NumStrings; ++i) { S = Strings[i]; // ObjC strings can't be wide. if (S->isWide()) { Diag(S->getLocStart(), diag::err_cfstring_literal_not_string_constant) << S->getSourceRange(); return true; } // Get the string data. StrBuf.append(S->getStrData(), S->getStrData()+S->getByteLength()); // Get the locations of the string tokens. StrLocs.append(S->tokloc_begin(), S->tokloc_end()); // Free the temporary string. S->Destroy(Context); } // Create the aggregate string with the appropriate content and location // information. S = StringLiteral::Create(Context, &StrBuf[0], StrBuf.size(), false, Context.getPointerType(Context.CharTy), &StrLocs[0], StrLocs.size()); } // Verify that this composite string is acceptable for ObjC strings. if (CheckObjCString(S)) return true; // Initialize the constant string interface lazily. This assumes // the NSString interface is seen in this translation unit. Note: We // don't use NSConstantString, since the runtime team considers this // interface private (even though it appears in the header files). QualType Ty = Context.getObjCConstantStringInterface(); if (!Ty.isNull()) { Ty = Context.getObjCObjectPointerType(Ty); } else if (getLangOptions().NoConstantCFStrings) { IdentifierInfo *NSIdent = &Context.Idents.get("NSConstantString"); NamedDecl *IF = LookupSingleName(TUScope, NSIdent, AtLocs[0], LookupOrdinaryName); if (ObjCInterfaceDecl *StrIF = dyn_cast_or_null(IF)) { Context.setObjCConstantStringInterface(StrIF); Ty = Context.getObjCConstantStringInterface(); Ty = Context.getObjCObjectPointerType(Ty); } else { // If there is no NSConstantString interface defined then treat this // as error and recover from it. Diag(S->getLocStart(), diag::err_no_nsconstant_string_class) << NSIdent << S->getSourceRange(); Ty = Context.getObjCIdType(); } } else { IdentifierInfo *NSIdent = &Context.Idents.get("NSString"); NamedDecl *IF = LookupSingleName(TUScope, NSIdent, AtLocs[0], LookupOrdinaryName); if (ObjCInterfaceDecl *StrIF = dyn_cast_or_null(IF)) { Context.setObjCConstantStringInterface(StrIF); Ty = Context.getObjCConstantStringInterface(); Ty = Context.getObjCObjectPointerType(Ty); } else { // If there is no NSString interface defined then treat constant // strings as untyped objects and let the runtime figure it out later. Ty = Context.getObjCIdType(); } } return new (Context) ObjCStringLiteral(S, Ty, AtLocs[0]); } Expr *Sema::BuildObjCEncodeExpression(SourceLocation AtLoc, TypeSourceInfo *EncodedTypeInfo, SourceLocation RParenLoc) { QualType EncodedType = EncodedTypeInfo->getType(); QualType StrTy; if (EncodedType->isDependentType()) StrTy = Context.DependentTy; else { std::string Str; Context.getObjCEncodingForType(EncodedType, Str); // The type of @encode is the same as the type of the corresponding string, // which is an array type. StrTy = Context.CharTy; // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). if (getLangOptions().CPlusPlus || getLangOptions().ConstStrings) StrTy.addConst(); StrTy = Context.getConstantArrayType(StrTy, llvm::APInt(32, Str.size()+1), ArrayType::Normal, 0); } return new (Context) ObjCEncodeExpr(StrTy, EncodedTypeInfo, AtLoc, RParenLoc); } Sema::ExprResult Sema::ParseObjCEncodeExpression(SourceLocation AtLoc, SourceLocation EncodeLoc, SourceLocation LParenLoc, TypeTy *ty, SourceLocation RParenLoc) { // FIXME: Preserve type source info ? TypeSourceInfo *TInfo; QualType EncodedType = GetTypeFromParser(ty, &TInfo); if (!TInfo) TInfo = Context.getTrivialTypeSourceInfo(EncodedType, PP.getLocForEndOfToken(LParenLoc)); return BuildObjCEncodeExpression(AtLoc, TInfo, RParenLoc); } Sema::ExprResult Sema::ParseObjCSelectorExpression(Selector Sel, SourceLocation AtLoc, SourceLocation SelLoc, SourceLocation LParenLoc, SourceLocation RParenLoc) { ObjCMethodDecl *Method = LookupInstanceMethodInGlobalPool(Sel, SourceRange(LParenLoc, RParenLoc), false); if (!Method) Method = LookupFactoryMethodInGlobalPool(Sel, SourceRange(LParenLoc, RParenLoc)); if (!Method) Diag(SelLoc, diag::warn_undeclared_selector) << Sel; QualType Ty = Context.getObjCSelType(); return new (Context) ObjCSelectorExpr(Ty, Sel, AtLoc, RParenLoc); } Sema::ExprResult Sema::ParseObjCProtocolExpression(IdentifierInfo *ProtocolId, SourceLocation AtLoc, SourceLocation ProtoLoc, SourceLocation LParenLoc, SourceLocation RParenLoc) { ObjCProtocolDecl* PDecl = LookupProtocol(ProtocolId, ProtoLoc); if (!PDecl) { Diag(ProtoLoc, diag::err_undeclared_protocol) << ProtocolId; return true; } QualType Ty = Context.getObjCProtoType(); if (Ty.isNull()) return true; Ty = Context.getObjCObjectPointerType(Ty); return new (Context) ObjCProtocolExpr(Ty, PDecl, AtLoc, RParenLoc); } bool Sema::CheckMessageArgumentTypes(Expr **Args, unsigned NumArgs, Selector Sel, ObjCMethodDecl *Method, bool isClassMessage, SourceLocation lbrac, SourceLocation rbrac, QualType &ReturnType) { if (!Method) { // Apply default argument promotion as for (C99 6.5.2.2p6). for (unsigned i = 0; i != NumArgs; i++) { if (Args[i]->isTypeDependent()) continue; DefaultArgumentPromotion(Args[i]); } unsigned DiagID = isClassMessage ? diag::warn_class_method_not_found : diag::warn_inst_method_not_found; Diag(lbrac, DiagID) << Sel << isClassMessage << SourceRange(lbrac, rbrac); ReturnType = Context.getObjCIdType(); return false; } ReturnType = Method->getSendResultType(); unsigned NumNamedArgs = Sel.getNumArgs(); // Method might have more arguments than selector indicates. This is due // to addition of c-style arguments in method. if (Method->param_size() > Sel.getNumArgs()) NumNamedArgs = Method->param_size(); // FIXME. This need be cleaned up. if (NumArgs < NumNamedArgs) { Diag(lbrac, diag::err_typecheck_call_too_few_args) << 2 << NumNamedArgs << NumArgs; return false; } bool IsError = false; for (unsigned i = 0; i < NumNamedArgs; i++) { // We can't do any type-checking on a type-dependent argument. if (Args[i]->isTypeDependent()) continue; Expr *argExpr = Args[i]; ParmVarDecl *Param = Method->param_begin()[i]; assert(argExpr && "CheckMessageArgumentTypes(): missing expression"); if (RequireCompleteType(argExpr->getSourceRange().getBegin(), Param->getType(), PDiag(diag::err_call_incomplete_argument) << argExpr->getSourceRange())) return true; InitializedEntity Entity = InitializedEntity::InitializeParameter(Param); OwningExprResult ArgE = PerformCopyInitialization(Entity, SourceLocation(), Owned(argExpr->Retain())); if (ArgE.isInvalid()) IsError = true; else Args[i] = ArgE.takeAs(); } // Promote additional arguments to variadic methods. if (Method->isVariadic()) { for (unsigned i = NumNamedArgs; i < NumArgs; ++i) { if (Args[i]->isTypeDependent()) continue; IsError |= DefaultVariadicArgumentPromotion(Args[i], VariadicMethod, 0); } } else { // Check for extra arguments to non-variadic methods. if (NumArgs != NumNamedArgs) { Diag(Args[NumNamedArgs]->getLocStart(), diag::err_typecheck_call_too_many_args) << 2 /*method*/ << NumNamedArgs << NumArgs << Method->getSourceRange() << SourceRange(Args[NumNamedArgs]->getLocStart(), Args[NumArgs-1]->getLocEnd()); } } DiagnoseSentinelCalls(Method, lbrac, Args, NumArgs); return IsError; } bool Sema::isSelfExpr(Expr *RExpr) { if (DeclRefExpr *DRE = dyn_cast(RExpr)) if (DRE->getDecl()->getIdentifier() == &Context.Idents.get("self")) return true; return false; } // Helper method for ActOnClassMethod/ActOnInstanceMethod. // Will search "local" class/category implementations for a method decl. // If failed, then we search in class's root for an instance method. // Returns 0 if no method is found. ObjCMethodDecl *Sema::LookupPrivateClassMethod(Selector Sel, ObjCInterfaceDecl *ClassDecl) { ObjCMethodDecl *Method = 0; // lookup in class and all superclasses while (ClassDecl && !Method) { if (ObjCImplementationDecl *ImpDecl = ClassDecl->getImplementation()) Method = ImpDecl->getClassMethod(Sel); // Look through local category implementations associated with the class. if (!Method) Method = ClassDecl->getCategoryClassMethod(Sel); // Before we give up, check if the selector is an instance method. // But only in the root. This matches gcc's behaviour and what the // runtime expects. if (!Method && !ClassDecl->getSuperClass()) { Method = ClassDecl->lookupInstanceMethod(Sel); // Look through local category implementations associated // with the root class. if (!Method) Method = LookupPrivateInstanceMethod(Sel, ClassDecl); } ClassDecl = ClassDecl->getSuperClass(); } return Method; } ObjCMethodDecl *Sema::LookupPrivateInstanceMethod(Selector Sel, ObjCInterfaceDecl *ClassDecl) { ObjCMethodDecl *Method = 0; while (ClassDecl && !Method) { // If we have implementations in scope, check "private" methods. if (ObjCImplementationDecl *ImpDecl = ClassDecl->getImplementation()) Method = ImpDecl->getInstanceMethod(Sel); // Look through local category implementations associated with the class. if (!Method) Method = ClassDecl->getCategoryInstanceMethod(Sel); ClassDecl = ClassDecl->getSuperClass(); } return Method; } /// HandleExprPropertyRefExpr - Handle foo.bar where foo is a pointer to an /// objective C interface. This is a property reference expression. Action::OwningExprResult Sema:: HandleExprPropertyRefExpr(const ObjCObjectPointerType *OPT, Expr *BaseExpr, DeclarationName MemberName, SourceLocation MemberLoc) { const ObjCInterfaceType *IFaceT = OPT->getInterfaceType(); ObjCInterfaceDecl *IFace = IFaceT->getDecl(); IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); // Search for a declared property first. if (ObjCPropertyDecl *PD = IFace->FindPropertyDeclaration(Member)) { // Check whether we can reference this property. if (DiagnoseUseOfDecl(PD, MemberLoc)) return ExprError(); QualType ResTy = PD->getType(); Selector Sel = PP.getSelectorTable().getNullarySelector(Member); ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); if (DiagnosePropertyAccessorMismatch(PD, Getter, MemberLoc)) ResTy = Getter->getSendResultType(); return Owned(new (Context) ObjCPropertyRefExpr(PD, ResTy, MemberLoc, BaseExpr)); } // Check protocols on qualified interfaces. for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(), E = OPT->qual_end(); I != E; ++I) if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { // Check whether we can reference this property. if (DiagnoseUseOfDecl(PD, MemberLoc)) return ExprError(); return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), MemberLoc, BaseExpr)); } // If that failed, look for an "implicit" property by seeing if the nullary // selector is implemented. // FIXME: The logic for looking up nullary and unary selectors should be // shared with the code in ActOnInstanceMessage. Selector Sel = PP.getSelectorTable().getNullarySelector(Member); ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); // If this reference is in an @implementation, check for 'private' methods. if (!Getter) Getter = IFace->lookupPrivateInstanceMethod(Sel); // Look through local category implementations associated with the class. if (!Getter) Getter = IFace->getCategoryInstanceMethod(Sel); if (Getter) { // Check if we can reference this property. if (DiagnoseUseOfDecl(Getter, MemberLoc)) return ExprError(); } // If we found a getter then this may be a valid dot-reference, we // will look for the matching setter, in case it is needed. Selector SetterSel = SelectorTable::constructSetterName(PP.getIdentifierTable(), PP.getSelectorTable(), Member); ObjCMethodDecl *Setter = IFace->lookupInstanceMethod(SetterSel); if (!Setter) { // If this reference is in an @implementation, also check for 'private' // methods. Setter = IFace->lookupPrivateInstanceMethod(SetterSel); } // Look through local category implementations associated with the class. if (!Setter) Setter = IFace->getCategoryInstanceMethod(SetterSel); if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) return ExprError(); if (Getter) { QualType PType; PType = Getter->getSendResultType(); return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, PType, Setter, MemberLoc, BaseExpr)); } // Attempt to correct for typos in property names. LookupResult Res(*this, MemberName, MemberLoc, LookupOrdinaryName); if (CorrectTypo(Res, 0, 0, IFace, false, CTC_NoKeywords, OPT) && Res.getAsSingle()) { DeclarationName TypoResult = Res.getLookupName(); Diag(MemberLoc, diag::err_property_not_found_suggest) << MemberName << QualType(OPT, 0) << TypoResult << FixItHint::CreateReplacement(MemberLoc, TypoResult.getAsString()); ObjCPropertyDecl *Property = Res.getAsSingle(); Diag(Property->getLocation(), diag::note_previous_decl) << Property->getDeclName(); return HandleExprPropertyRefExpr(OPT, BaseExpr, TypoResult, MemberLoc); } Diag(MemberLoc, diag::err_property_not_found) << MemberName << QualType(OPT, 0); if (Setter && !Getter) Diag(Setter->getLocation(), diag::note_getter_unavailable) << MemberName << BaseExpr->getSourceRange(); return ExprError(); } Action::OwningExprResult Sema:: ActOnClassPropertyRefExpr(IdentifierInfo &receiverName, IdentifierInfo &propertyName, SourceLocation receiverNameLoc, SourceLocation propertyNameLoc) { IdentifierInfo *receiverNamePtr = &receiverName; ObjCInterfaceDecl *IFace = getObjCInterfaceDecl(receiverNamePtr, receiverNameLoc); if (IFace == 0) { // If the "receiver" is 'super' in a method, handle it as an expression-like // property reference. if (ObjCMethodDecl *CurMethod = getCurMethodDecl()) if (receiverNamePtr->isStr("super")) { if (CurMethod->isInstanceMethod()) { QualType T = Context.getObjCInterfaceType(CurMethod->getClassInterface()); T = Context.getObjCObjectPointerType(T); Expr *SuperExpr = new (Context) ObjCSuperExpr(receiverNameLoc, T); return HandleExprPropertyRefExpr(T->getAsObjCInterfacePointerType(), SuperExpr, &propertyName, propertyNameLoc); } // Otherwise, if this is a class method, try dispatching to our // superclass. IFace = CurMethod->getClassInterface()->getSuperClass(); } if (IFace == 0) { Diag(receiverNameLoc, diag::err_expected_ident_or_lparen); return ExprError(); } } // Search for a declared property first. Selector Sel = PP.getSelectorTable().getNullarySelector(&propertyName); ObjCMethodDecl *Getter = IFace->lookupClassMethod(Sel); // If this reference is in an @implementation, check for 'private' methods. if (!Getter) if (ObjCMethodDecl *CurMeth = getCurMethodDecl()) if (ObjCInterfaceDecl *ClassDecl = CurMeth->getClassInterface()) if (ObjCImplementationDecl *ImpDecl = ClassDecl->getImplementation()) Getter = ImpDecl->getClassMethod(Sel); if (Getter) { // FIXME: refactor/share with ActOnMemberReference(). // Check if we can reference this property. if (DiagnoseUseOfDecl(Getter, propertyNameLoc)) return ExprError(); } // Look for the matching setter, in case it is needed. Selector SetterSel = SelectorTable::constructSetterName(PP.getIdentifierTable(), PP.getSelectorTable(), &propertyName); ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); if (!Setter) { // If this reference is in an @implementation, also check for 'private' // methods. if (ObjCMethodDecl *CurMeth = getCurMethodDecl()) if (ObjCInterfaceDecl *ClassDecl = CurMeth->getClassInterface()) if (ObjCImplementationDecl *ImpDecl = ClassDecl->getImplementation()) Setter = ImpDecl->getClassMethod(SetterSel); } // Look through local category implementations associated with the class. if (!Setter) Setter = IFace->getCategoryClassMethod(SetterSel); if (Setter && DiagnoseUseOfDecl(Setter, propertyNameLoc)) return ExprError(); if (Getter || Setter) { QualType PType; if (Getter) PType = Getter->getSendResultType(); else { for (ObjCMethodDecl::param_iterator PI = Setter->param_begin(), E = Setter->param_end(); PI != E; ++PI) PType = (*PI)->getType(); } return Owned(new (Context) ObjCImplicitSetterGetterRefExpr( Getter, PType, Setter, propertyNameLoc, IFace, receiverNameLoc)); } return ExprError(Diag(propertyNameLoc, diag::err_property_not_found) << &propertyName << Context.getObjCInterfaceType(IFace)); } Sema::ObjCMessageKind Sema::getObjCMessageKind(Scope *S, IdentifierInfo *Name, SourceLocation NameLoc, bool IsSuper, bool HasTrailingDot, TypeTy *&ReceiverType) { ReceiverType = 0; // If the identifier is "super" and there is no trailing dot, we're // messaging super. if (IsSuper && !HasTrailingDot && S->isInObjcMethodScope()) return ObjCSuperMessage; LookupResult Result(*this, Name, NameLoc, LookupOrdinaryName); LookupName(Result, S); switch (Result.getResultKind()) { case LookupResult::NotFound: // Normal name lookup didn't find anything. If we're in an // Objective-C method, look for ivars. If we find one, we're done! // FIXME: This is a hack. Ivar lookup should be part of normal lookup. if (ObjCMethodDecl *Method = getCurMethodDecl()) { ObjCInterfaceDecl *ClassDeclared; if (Method->getClassInterface()->lookupInstanceVariable(Name, ClassDeclared)) return ObjCInstanceMessage; } // Break out; we'll perform typo correction below. break; case LookupResult::NotFoundInCurrentInstantiation: case LookupResult::FoundOverloaded: case LookupResult::FoundUnresolvedValue: case LookupResult::Ambiguous: Result.suppressDiagnostics(); return ObjCInstanceMessage; case LookupResult::Found: { // We found something. If it's a type, then we have a class // message. Otherwise, it's an instance message. NamedDecl *ND = Result.getFoundDecl(); QualType T; if (ObjCInterfaceDecl *Class = dyn_cast(ND)) T = Context.getObjCInterfaceType(Class); else if (TypeDecl *Type = dyn_cast(ND)) T = Context.getTypeDeclType(Type); else return ObjCInstanceMessage; // We have a class message, and T is the type we're // messaging. Build source-location information for it. TypeSourceInfo *TSInfo = Context.getTrivialTypeSourceInfo(T, NameLoc); ReceiverType = CreateLocInfoType(T, TSInfo).getAsOpaquePtr(); return ObjCClassMessage; } } // Determine our typo-correction context. CorrectTypoContext CTC = CTC_Expression; if (ObjCMethodDecl *Method = getCurMethodDecl()) if (Method->getClassInterface() && Method->getClassInterface()->getSuperClass()) CTC = CTC_ObjCMessageReceiver; if (DeclarationName Corrected = CorrectTypo(Result, S, 0, 0, false, CTC)) { if (Result.isSingleResult()) { // If we found a declaration, correct when it refers to an Objective-C // class. NamedDecl *ND = Result.getFoundDecl(); if (ObjCInterfaceDecl *Class = dyn_cast(ND)) { Diag(NameLoc, diag::err_unknown_receiver_suggest) << Name << Result.getLookupName() << FixItHint::CreateReplacement(SourceRange(NameLoc), ND->getNameAsString()); Diag(ND->getLocation(), diag::note_previous_decl) << Corrected; QualType T = Context.getObjCInterfaceType(Class); TypeSourceInfo *TSInfo = Context.getTrivialTypeSourceInfo(T, NameLoc); ReceiverType = CreateLocInfoType(T, TSInfo).getAsOpaquePtr(); return ObjCClassMessage; } } else if (Result.empty() && Corrected.getAsIdentifierInfo() && Corrected.getAsIdentifierInfo()->isStr("super")) { // If we've found the keyword "super", this is a send to super. Diag(NameLoc, diag::err_unknown_receiver_suggest) << Name << Corrected << FixItHint::CreateReplacement(SourceRange(NameLoc), "super"); Name = Corrected.getAsIdentifierInfo(); return ObjCSuperMessage; } } // Fall back: let the parser try to parse it as an instance message. return ObjCInstanceMessage; } Sema::OwningExprResult Sema::ActOnSuperMessage(Scope *S, SourceLocation SuperLoc, Selector Sel, SourceLocation LBracLoc, SourceLocation SelectorLoc, SourceLocation RBracLoc, MultiExprArg Args) { // Determine whether we are inside a method or not. ObjCMethodDecl *Method = getCurMethodDecl(); if (!Method) { Diag(SuperLoc, diag::err_invalid_receiver_to_message_super); return ExprError(); } ObjCInterfaceDecl *Class = Method->getClassInterface(); if (!Class) { Diag(SuperLoc, diag::error_no_super_class_message) << Method->getDeclName(); return ExprError(); } ObjCInterfaceDecl *Super = Class->getSuperClass(); if (!Super) { // The current class does not have a superclass. Diag(SuperLoc, diag::error_no_super_class) << Class->getIdentifier(); return ExprError(); } // We are in a method whose class has a superclass, so 'super' // is acting as a keyword. if (Method->isInstanceMethod()) { // Since we are in an instance method, this is an instance // message to the superclass instance. QualType SuperTy = Context.getObjCInterfaceType(Super); SuperTy = Context.getObjCObjectPointerType(SuperTy); return BuildInstanceMessage(ExprArg(*this), SuperTy, SuperLoc, Sel, /*Method=*/0, LBracLoc, RBracLoc, move(Args)); } // Since we are in a class method, this is a class message to // the superclass. return BuildClassMessage(/*ReceiverTypeInfo=*/0, Context.getObjCInterfaceType(Super), SuperLoc, Sel, /*Method=*/0, LBracLoc, RBracLoc, move(Args)); } /// \brief Build an Objective-C class message expression. /// /// This routine takes care of both normal class messages and /// class messages to the superclass. /// /// \param ReceiverTypeInfo Type source information that describes the /// receiver of this message. This may be NULL, in which case we are /// sending to the superclass and \p SuperLoc must be a valid source /// location. /// \param ReceiverType The type of the object receiving the /// message. When \p ReceiverTypeInfo is non-NULL, this is the same /// type as that refers to. For a superclass send, this is the type of /// the superclass. /// /// \param SuperLoc The location of the "super" keyword in a /// superclass message. /// /// \param Sel The selector to which the message is being sent. /// /// \param Method The method that this class message is invoking, if /// already known. /// /// \param LBracLoc The location of the opening square bracket ']'. /// /// \param RBrac The location of the closing square bracket ']'. /// /// \param Args The message arguments. Sema::OwningExprResult Sema::BuildClassMessage(TypeSourceInfo *ReceiverTypeInfo, QualType ReceiverType, SourceLocation SuperLoc, Selector Sel, ObjCMethodDecl *Method, SourceLocation LBracLoc, SourceLocation RBracLoc, MultiExprArg ArgsIn) { if (ReceiverType->isDependentType()) { // If the receiver type is dependent, we can't type-check anything // at this point. Build a dependent expression. unsigned NumArgs = ArgsIn.size(); Expr **Args = reinterpret_cast(ArgsIn.release()); assert(SuperLoc.isInvalid() && "Message to super with dependent type"); return Owned(ObjCMessageExpr::Create(Context, ReceiverType, LBracLoc, ReceiverTypeInfo, Sel, /*Method=*/0, Args, NumArgs, RBracLoc)); } SourceLocation Loc = SuperLoc.isValid()? SuperLoc : ReceiverTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(); // Find the class to which we are sending this message. ObjCInterfaceDecl *Class = 0; const ObjCObjectType *ClassType = ReceiverType->getAs(); if (!ClassType || !(Class = ClassType->getInterface())) { Diag(Loc, diag::err_invalid_receiver_class_message) << ReceiverType; return ExprError(); } assert(Class && "We don't know which class we're messaging?"); // Find the method we are messaging. if (!Method) { if (Class->isForwardDecl()) { // A forward class used in messaging is treated as a 'Class' Diag(Loc, diag::warn_receiver_forward_class) << Class->getDeclName(); Method = LookupFactoryMethodInGlobalPool(Sel, SourceRange(LBracLoc, RBracLoc)); if (Method) Diag(Method->getLocation(), diag::note_method_sent_forward_class) << Method->getDeclName(); } if (!Method) Method = Class->lookupClassMethod(Sel); // If we have an implementation in scope, check "private" methods. if (!Method) Method = LookupPrivateClassMethod(Sel, Class); if (Method && DiagnoseUseOfDecl(Method, Loc)) return ExprError(); } // Check the argument types and determine the result type. QualType ReturnType; unsigned NumArgs = ArgsIn.size(); Expr **Args = reinterpret_cast(ArgsIn.release()); if (CheckMessageArgumentTypes(Args, NumArgs, Sel, Method, true, LBracLoc, RBracLoc, ReturnType)) { for (unsigned I = 0; I != NumArgs; ++I) Args[I]->Destroy(Context); return ExprError(); } // Construct the appropriate ObjCMessageExpr. Expr *Result; if (SuperLoc.isValid()) Result = ObjCMessageExpr::Create(Context, ReturnType, LBracLoc, SuperLoc, /*IsInstanceSuper=*/false, ReceiverType, Sel, Method, Args, NumArgs, RBracLoc); else Result = ObjCMessageExpr::Create(Context, ReturnType, LBracLoc, ReceiverTypeInfo, Sel, Method, Args, NumArgs, RBracLoc); return MaybeBindToTemporary(Result); } // ActOnClassMessage - used for both unary and keyword messages. // ArgExprs is optional - if it is present, the number of expressions // is obtained from Sel.getNumArgs(). Sema::OwningExprResult Sema::ActOnClassMessage(Scope *S, TypeTy *Receiver, Selector Sel, SourceLocation LBracLoc, SourceLocation SelectorLoc, SourceLocation RBracLoc, MultiExprArg Args) { TypeSourceInfo *ReceiverTypeInfo; QualType ReceiverType = GetTypeFromParser(Receiver, &ReceiverTypeInfo); if (ReceiverType.isNull()) return ExprError(); if (!ReceiverTypeInfo) ReceiverTypeInfo = Context.getTrivialTypeSourceInfo(ReceiverType, LBracLoc); return BuildClassMessage(ReceiverTypeInfo, ReceiverType, /*SuperLoc=*/SourceLocation(), Sel, /*Method=*/0, LBracLoc, RBracLoc, move(Args)); } /// \brief Build an Objective-C instance message expression. /// /// This routine takes care of both normal instance messages and /// instance messages to the superclass instance. /// /// \param Receiver The expression that computes the object that will /// receive this message. This may be empty, in which case we are /// sending to the superclass instance and \p SuperLoc must be a valid /// source location. /// /// \param ReceiverType The (static) type of the object receiving the /// message. When a \p Receiver expression is provided, this is the /// same type as that expression. For a superclass instance send, this /// is a pointer to the type of the superclass. /// /// \param SuperLoc The location of the "super" keyword in a /// superclass instance message. /// /// \param Sel The selector to which the message is being sent. /// /// \param Method The method that this instance message is invoking, if /// already known. /// /// \param LBracLoc The location of the opening square bracket ']'. /// /// \param RBrac The location of the closing square bracket ']'. /// /// \param Args The message arguments. Sema::OwningExprResult Sema::BuildInstanceMessage(ExprArg ReceiverE, QualType ReceiverType, SourceLocation SuperLoc, Selector Sel, ObjCMethodDecl *Method, SourceLocation LBracLoc, SourceLocation RBracLoc, MultiExprArg ArgsIn) { // If we have a receiver expression, perform appropriate promotions // and determine receiver type. Expr *Receiver = ReceiverE.takeAs(); if (Receiver) { if (Receiver->isTypeDependent()) { // If the receiver is type-dependent, we can't type-check anything // at this point. Build a dependent expression. unsigned NumArgs = ArgsIn.size(); Expr **Args = reinterpret_cast(ArgsIn.release()); assert(SuperLoc.isInvalid() && "Message to super with dependent type"); return Owned(ObjCMessageExpr::Create(Context, Context.DependentTy, LBracLoc, Receiver, Sel, /*Method=*/0, Args, NumArgs, RBracLoc)); } // If necessary, apply function/array conversion to the receiver. // C99 6.7.5.3p[7,8]. DefaultFunctionArrayLvalueConversion(Receiver); ReceiverType = Receiver->getType(); } // The location of the receiver. SourceLocation Loc = SuperLoc.isValid()? SuperLoc : Receiver->getLocStart(); if (!Method) { // Handle messages to id. if (ReceiverType->isObjCIdType() || ReceiverType->isBlockPointerType() || (Receiver && Context.isObjCNSObjectType(Receiver->getType()))) { Method = LookupInstanceMethodInGlobalPool(Sel, SourceRange(LBracLoc, RBracLoc)); if (!Method) Method = LookupFactoryMethodInGlobalPool(Sel, SourceRange(LBracLoc, RBracLoc)); } else if (ReceiverType->isObjCClassType() || ReceiverType->isObjCQualifiedClassType()) { // Handle messages to Class. if (ObjCMethodDecl *CurMeth = getCurMethodDecl()) { if (ObjCInterfaceDecl *ClassDecl = CurMeth->getClassInterface()) { // First check the public methods in the class interface. Method = ClassDecl->lookupClassMethod(Sel); if (!Method) Method = LookupPrivateClassMethod(Sel, ClassDecl); // FIXME: if we still haven't found a method, we need to look in // protocols (if we have qualifiers). } if (Method && DiagnoseUseOfDecl(Method, Loc)) return ExprError(); } if (!Method) { // If not messaging 'self', look for any factory method named 'Sel'. if (!Receiver || !isSelfExpr(Receiver)) { Method = LookupFactoryMethodInGlobalPool(Sel, SourceRange(LBracLoc, RBracLoc)); if (!Method) { // If no class (factory) method was found, check if an _instance_ // method of the same name exists in the root class only. Method = LookupInstanceMethodInGlobalPool(Sel, SourceRange(LBracLoc, RBracLoc)); if (Method) if (const ObjCInterfaceDecl *ID = dyn_cast(Method->getDeclContext())) { if (ID->getSuperClass()) Diag(Loc, diag::warn_root_inst_method_not_found) << Sel << SourceRange(LBracLoc, RBracLoc); } } } } } else { ObjCInterfaceDecl* ClassDecl = 0; // We allow sending a message to a qualified ID ("id"), which is ok as // long as one of the protocols implements the selector (if not, warn). if (const ObjCObjectPointerType *QIdTy = ReceiverType->getAsObjCQualifiedIdType()) { // Search protocols for instance methods. for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), E = QIdTy->qual_end(); I != E; ++I) { ObjCProtocolDecl *PDecl = *I; if (PDecl && (Method = PDecl->lookupInstanceMethod(Sel))) break; // Since we aren't supporting "Class", look for a class method. if (PDecl && (Method = PDecl->lookupClassMethod(Sel))) break; } } else if (const ObjCObjectPointerType *OCIType = ReceiverType->getAsObjCInterfacePointerType()) { // We allow sending a message to a pointer to an interface (an object). ClassDecl = OCIType->getInterfaceDecl(); // FIXME: consider using LookupInstanceMethodInGlobalPool, since it will be // faster than the following method (which can do *many* linear searches). // The idea is to add class info to InstanceMethodPool. Method = ClassDecl->lookupInstanceMethod(Sel); if (!Method) { // Search protocol qualifiers. for (ObjCObjectPointerType::qual_iterator QI = OCIType->qual_begin(), E = OCIType->qual_end(); QI != E; ++QI) { if ((Method = (*QI)->lookupInstanceMethod(Sel))) break; } } if (!Method) { // If we have implementations in scope, check "private" methods. Method = LookupPrivateInstanceMethod(Sel, ClassDecl); if (!Method && (!Receiver || !isSelfExpr(Receiver))) { // If we still haven't found a method, look in the global pool. This // behavior isn't very desirable, however we need it for GCC // compatibility. FIXME: should we deviate?? if (OCIType->qual_empty()) { Method = LookupInstanceMethodInGlobalPool(Sel, SourceRange(LBracLoc, RBracLoc)); if (Method && !OCIType->getInterfaceDecl()->isForwardDecl()) Diag(Loc, diag::warn_maynot_respond) << OCIType->getInterfaceDecl()->getIdentifier() << Sel; } } } if (Method && DiagnoseUseOfDecl(Method, Loc)) return ExprError(); } else if (!Context.getObjCIdType().isNull() && (ReceiverType->isPointerType() || (ReceiverType->isIntegerType() && ReceiverType->isScalarType()))) { // Implicitly convert integers and pointers to 'id' but emit a warning. Diag(Loc, diag::warn_bad_receiver_type) << ReceiverType << Receiver->getSourceRange(); if (ReceiverType->isPointerType()) ImpCastExprToType(Receiver, Context.getObjCIdType(), CastExpr::CK_BitCast); else ImpCastExprToType(Receiver, Context.getObjCIdType(), CastExpr::CK_IntegralToPointer); ReceiverType = Receiver->getType(); } else if (getLangOptions().CPlusPlus && !PerformContextuallyConvertToObjCId(Receiver)) { if (ImplicitCastExpr *ICE = dyn_cast(Receiver)) { Receiver = ICE->getSubExpr(); ReceiverType = Receiver->getType(); } return BuildInstanceMessage(Owned(Receiver), ReceiverType, SuperLoc, Sel, Method, LBracLoc, RBracLoc, move(ArgsIn)); } else { // Reject other random receiver types (e.g. structs). Diag(Loc, diag::err_bad_receiver_type) << ReceiverType << Receiver->getSourceRange(); return ExprError(); } } } // Check the message arguments. unsigned NumArgs = ArgsIn.size(); Expr **Args = reinterpret_cast(ArgsIn.release()); QualType ReturnType; if (CheckMessageArgumentTypes(Args, NumArgs, Sel, Method, false, LBracLoc, RBracLoc, ReturnType)) return ExprError(); if (!ReturnType->isVoidType()) { if (RequireCompleteType(LBracLoc, ReturnType, diag::err_illegal_message_expr_incomplete_type)) return ExprError(); } // Construct the appropriate ObjCMessageExpr instance. Expr *Result; if (SuperLoc.isValid()) Result = ObjCMessageExpr::Create(Context, ReturnType, LBracLoc, SuperLoc, /*IsInstanceSuper=*/true, ReceiverType, Sel, Method, Args, NumArgs, RBracLoc); else Result = ObjCMessageExpr::Create(Context, ReturnType, LBracLoc, Receiver, Sel, Method, Args, NumArgs, RBracLoc); return MaybeBindToTemporary(Result); } // ActOnInstanceMessage - used for both unary and keyword messages. // ArgExprs is optional - if it is present, the number of expressions // is obtained from Sel.getNumArgs(). Sema::OwningExprResult Sema::ActOnInstanceMessage(Scope *S, ExprArg ReceiverE, Selector Sel, SourceLocation LBracLoc, SourceLocation SelectorLoc, SourceLocation RBracLoc, MultiExprArg Args) { Expr *Receiver = static_cast(ReceiverE.get()); if (!Receiver) return ExprError(); return BuildInstanceMessage(move(ReceiverE), Receiver->getType(), /*SuperLoc=*/SourceLocation(), Sel, /*Method=*/0, LBracLoc, RBracLoc, move(Args)); }