| //===--- Sema.cpp - AST Builder and Semantic Analysis Implementation ------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements the actions class which performs semantic analysis and |
| // builds an AST out of a parse stream. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "Sema.h" |
| #include "TargetAttributesSema.h" |
| #include "llvm/ADT/DenseMap.h" |
| #include "llvm/ADT/SmallSet.h" |
| #include "llvm/ADT/APFloat.h" |
| #include "clang/AST/ASTConsumer.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/AST/ASTDiagnostic.h" |
| #include "clang/AST/DeclObjC.h" |
| #include "clang/AST/Expr.h" |
| #include "clang/Lex/Preprocessor.h" |
| #include "clang/Basic/PartialDiagnostic.h" |
| #include "clang/Basic/TargetInfo.h" |
| using namespace clang; |
| |
| FunctionScopeInfo::~FunctionScopeInfo() { } |
| |
| void FunctionScopeInfo::Clear(unsigned NumErrors) { |
| NeedsScopeChecking = false; |
| LabelMap.clear(); |
| SwitchStack.clear(); |
| NumErrorsAtStartOfFunction = NumErrors; |
| } |
| |
| BlockScopeInfo::~BlockScopeInfo() { } |
| |
| static inline RecordDecl *CreateStructDecl(ASTContext &C, const char *Name) { |
| if (C.getLangOptions().CPlusPlus) |
| return CXXRecordDecl::Create(C, TagDecl::TK_struct, |
| C.getTranslationUnitDecl(), |
| SourceLocation(), &C.Idents.get(Name)); |
| |
| return RecordDecl::Create(C, TagDecl::TK_struct, |
| C.getTranslationUnitDecl(), |
| SourceLocation(), &C.Idents.get(Name)); |
| } |
| |
| void Sema::ActOnTranslationUnitScope(SourceLocation Loc, Scope *S) { |
| TUScope = S; |
| PushDeclContext(S, Context.getTranslationUnitDecl()); |
| |
| if (PP.getTargetInfo().getPointerWidth(0) >= 64) { |
| TypeSourceInfo *TInfo; |
| |
| // Install [u]int128_t for 64-bit targets. |
| TInfo = Context.getTrivialTypeSourceInfo(Context.Int128Ty); |
| PushOnScopeChains(TypedefDecl::Create(Context, CurContext, |
| SourceLocation(), |
| &Context.Idents.get("__int128_t"), |
| TInfo), TUScope); |
| |
| TInfo = Context.getTrivialTypeSourceInfo(Context.UnsignedInt128Ty); |
| PushOnScopeChains(TypedefDecl::Create(Context, CurContext, |
| SourceLocation(), |
| &Context.Idents.get("__uint128_t"), |
| TInfo), TUScope); |
| } |
| |
| |
| if (!PP.getLangOptions().ObjC1) return; |
| |
| // Built-in ObjC types may already be set by PCHReader (hence isNull checks). |
| if (Context.getObjCSelType().isNull()) { |
| // Create the built-in typedef for 'SEL'. |
| QualType SelT = Context.getPointerType(Context.ObjCBuiltinSelTy); |
| TypeSourceInfo *SelInfo = Context.getTrivialTypeSourceInfo(SelT); |
| TypedefDecl *SelTypedef |
| = TypedefDecl::Create(Context, CurContext, SourceLocation(), |
| &Context.Idents.get("SEL"), SelInfo); |
| PushOnScopeChains(SelTypedef, TUScope); |
| Context.setObjCSelType(Context.getTypeDeclType(SelTypedef)); |
| Context.ObjCSelRedefinitionType = Context.getObjCSelType(); |
| } |
| |
| // Synthesize "@class Protocol; |
| if (Context.getObjCProtoType().isNull()) { |
| ObjCInterfaceDecl *ProtocolDecl = |
| ObjCInterfaceDecl::Create(Context, CurContext, SourceLocation(), |
| &Context.Idents.get("Protocol"), |
| SourceLocation(), true); |
| Context.setObjCProtoType(Context.getObjCInterfaceType(ProtocolDecl)); |
| PushOnScopeChains(ProtocolDecl, TUScope, false); |
| } |
| // Create the built-in typedef for 'id'. |
| if (Context.getObjCIdType().isNull()) { |
| QualType IdT = Context.getObjCObjectPointerType(Context.ObjCBuiltinIdTy); |
| TypeSourceInfo *IdInfo = Context.getTrivialTypeSourceInfo(IdT); |
| TypedefDecl *IdTypedef |
| = TypedefDecl::Create(Context, CurContext, SourceLocation(), |
| &Context.Idents.get("id"), IdInfo); |
| PushOnScopeChains(IdTypedef, TUScope); |
| Context.setObjCIdType(Context.getTypeDeclType(IdTypedef)); |
| Context.ObjCIdRedefinitionType = Context.getObjCIdType(); |
| } |
| // Create the built-in typedef for 'Class'. |
| if (Context.getObjCClassType().isNull()) { |
| QualType ClassType |
| = Context.getObjCObjectPointerType(Context.ObjCBuiltinClassTy); |
| TypeSourceInfo *ClassInfo = Context.getTrivialTypeSourceInfo(ClassType); |
| TypedefDecl *ClassTypedef |
| = TypedefDecl::Create(Context, CurContext, SourceLocation(), |
| &Context.Idents.get("Class"), ClassInfo); |
| PushOnScopeChains(ClassTypedef, TUScope); |
| Context.setObjCClassType(Context.getTypeDeclType(ClassTypedef)); |
| Context.ObjCClassRedefinitionType = Context.getObjCClassType(); |
| } |
| } |
| |
| Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer, |
| bool CompleteTranslationUnit, |
| CodeCompleteConsumer *CodeCompleter) |
| : TheTargetAttributesSema(0), |
| LangOpts(pp.getLangOptions()), PP(pp), Context(ctxt), Consumer(consumer), |
| Diags(PP.getDiagnostics()), SourceMgr(PP.getSourceManager()), |
| ExternalSource(0), CodeCompleter(CodeCompleter), CurContext(0), |
| PackContext(0), TopFunctionScope(0), ParsingDeclDepth(0), |
| IdResolver(pp.getLangOptions()), StdNamespace(0), StdBadAlloc(0), |
| GlobalNewDeleteDeclared(false), |
| CompleteTranslationUnit(CompleteTranslationUnit), |
| NumSFINAEErrors(0), NonInstantiationEntries(0), |
| CurrentInstantiationScope(0), TyposCorrected(0) |
| { |
| TUScope = 0; |
| if (getLangOptions().CPlusPlus) |
| FieldCollector.reset(new CXXFieldCollector()); |
| |
| // Tell diagnostics how to render things from the AST library. |
| PP.getDiagnostics().SetArgToStringFn(&FormatASTNodeDiagnosticArgument, |
| &Context); |
| |
| ExprEvalContexts.push_back( |
| ExpressionEvaluationContextRecord(PotentiallyEvaluated, 0)); |
| } |
| |
| Sema::~Sema() { |
| if (PackContext) FreePackedContext(); |
| delete TheTargetAttributesSema; |
| while (!FunctionScopes.empty()) |
| PopFunctionOrBlockScope(); |
| } |
| |
| /// ImpCastExprToType - If Expr is not of type 'Type', insert an implicit cast. |
| /// If there is already an implicit cast, merge into the existing one. |
| /// If isLvalue, the result of the cast is an lvalue. |
| void Sema::ImpCastExprToType(Expr *&Expr, QualType Ty, |
| CastExpr::CastKind Kind, bool isLvalue) { |
| QualType ExprTy = Context.getCanonicalType(Expr->getType()); |
| QualType TypeTy = Context.getCanonicalType(Ty); |
| |
| if (ExprTy == TypeTy) |
| return; |
| |
| if (Expr->getType()->isPointerType() && Ty->isPointerType()) { |
| QualType ExprBaseType = cast<PointerType>(ExprTy)->getPointeeType(); |
| QualType BaseType = cast<PointerType>(TypeTy)->getPointeeType(); |
| if (ExprBaseType.getAddressSpace() != BaseType.getAddressSpace()) { |
| Diag(Expr->getExprLoc(), diag::err_implicit_pointer_address_space_cast) |
| << Expr->getSourceRange(); |
| } |
| } |
| |
| CheckImplicitConversion(Expr, Ty); |
| |
| if (ImplicitCastExpr *ImpCast = dyn_cast<ImplicitCastExpr>(Expr)) { |
| if (ImpCast->getCastKind() == Kind) { |
| ImpCast->setType(Ty); |
| ImpCast->setLvalueCast(isLvalue); |
| return; |
| } |
| } |
| |
| Expr = new (Context) ImplicitCastExpr(Ty, Kind, Expr, isLvalue); |
| } |
| |
| void Sema::DeleteExpr(ExprTy *E) { |
| if (E) static_cast<Expr*>(E)->Destroy(Context); |
| } |
| void Sema::DeleteStmt(StmtTy *S) { |
| if (S) static_cast<Stmt*>(S)->Destroy(Context); |
| } |
| |
| /// ActOnEndOfTranslationUnit - This is called at the very end of the |
| /// translation unit when EOF is reached and all but the top-level scope is |
| /// popped. |
| void Sema::ActOnEndOfTranslationUnit() { |
| |
| // Remove functions that turned out to be used. |
| UnusedStaticFuncs.erase(std::remove_if(UnusedStaticFuncs.begin(), |
| UnusedStaticFuncs.end(), |
| std::mem_fun(&FunctionDecl::isUsed)), |
| UnusedStaticFuncs.end()); |
| |
| while (1) { |
| // C++: Perform implicit template instantiations. |
| // |
| // FIXME: When we perform these implicit instantiations, we do not carefully |
| // keep track of the point of instantiation (C++ [temp.point]). This means |
| // that name lookup that occurs within the template instantiation will |
| // always happen at the end of the translation unit, so it will find |
| // some names that should not be found. Although this is common behavior |
| // for C++ compilers, it is technically wrong. In the future, we either need |
| // to be able to filter the results of name lookup or we need to perform |
| // template instantiations earlier. |
| PerformPendingImplicitInstantiations(); |
| |
| /// If ProcessPendingClassesWithUnmarkedVirtualMembers ends up marking |
| /// any virtual member functions it might lead to more pending template |
| /// instantiations, which is why we need to loop here. |
| if (!ProcessPendingClassesWithUnmarkedVirtualMembers()) |
| break; |
| } |
| |
| // Check for #pragma weak identifiers that were never declared |
| // FIXME: This will cause diagnostics to be emitted in a non-determinstic |
| // order! Iterating over a densemap like this is bad. |
| for (llvm::DenseMap<IdentifierInfo*,WeakInfo>::iterator |
| I = WeakUndeclaredIdentifiers.begin(), |
| E = WeakUndeclaredIdentifiers.end(); I != E; ++I) { |
| if (I->second.getUsed()) continue; |
| |
| Diag(I->second.getLocation(), diag::warn_weak_identifier_undeclared) |
| << I->first; |
| } |
| |
| if (!CompleteTranslationUnit) |
| return; |
| |
| // C99 6.9.2p2: |
| // A declaration of an identifier for an object that has file |
| // scope without an initializer, and without a storage-class |
| // specifier or with the storage-class specifier static, |
| // constitutes a tentative definition. If a translation unit |
| // contains one or more tentative definitions for an identifier, |
| // and the translation unit contains no external definition for |
| // that identifier, then the behavior is exactly as if the |
| // translation unit contains a file scope declaration of that |
| // identifier, with the composite type as of the end of the |
| // translation unit, with an initializer equal to 0. |
| llvm::SmallSet<VarDecl *, 32> Seen; |
| for (unsigned i = 0, e = TentativeDefinitions.size(); i != e; ++i) { |
| VarDecl *VD = TentativeDefinitions[i]->getActingDefinition(); |
| |
| // If the tentative definition was completed, getActingDefinition() returns |
| // null. If we've already seen this variable before, insert()'s second |
| // return value is false. |
| if (VD == 0 || VD->isInvalidDecl() || !Seen.insert(VD)) |
| continue; |
| |
| if (const IncompleteArrayType *ArrayT |
| = Context.getAsIncompleteArrayType(VD->getType())) { |
| if (RequireCompleteType(VD->getLocation(), |
| ArrayT->getElementType(), |
| diag::err_tentative_def_incomplete_type_arr)) { |
| VD->setInvalidDecl(); |
| continue; |
| } |
| |
| // Set the length of the array to 1 (C99 6.9.2p5). |
| Diag(VD->getLocation(), diag::warn_tentative_incomplete_array); |
| llvm::APInt One(Context.getTypeSize(Context.getSizeType()), true); |
| QualType T = Context.getConstantArrayType(ArrayT->getElementType(), |
| One, ArrayType::Normal, 0); |
| VD->setType(T); |
| } else if (RequireCompleteType(VD->getLocation(), VD->getType(), |
| diag::err_tentative_def_incomplete_type)) |
| VD->setInvalidDecl(); |
| |
| // Notify the consumer that we've completed a tentative definition. |
| if (!VD->isInvalidDecl()) |
| Consumer.CompleteTentativeDefinition(VD); |
| |
| } |
| |
| // Output warning for unused functions. |
| for (std::vector<FunctionDecl*>::iterator |
| F = UnusedStaticFuncs.begin(), |
| FEnd = UnusedStaticFuncs.end(); |
| F != FEnd; |
| ++F) |
| Diag((*F)->getLocation(), diag::warn_unused_function) << (*F)->getDeclName(); |
| |
| } |
| |
| |
| //===----------------------------------------------------------------------===// |
| // Helper functions. |
| //===----------------------------------------------------------------------===// |
| |
| DeclContext *Sema::getFunctionLevelDeclContext() { |
| DeclContext *DC = CurContext; |
| |
| while (isa<BlockDecl>(DC)) |
| DC = DC->getParent(); |
| |
| return DC; |
| } |
| |
| /// getCurFunctionDecl - If inside of a function body, this returns a pointer |
| /// to the function decl for the function being parsed. If we're currently |
| /// in a 'block', this returns the containing context. |
| FunctionDecl *Sema::getCurFunctionDecl() { |
| DeclContext *DC = getFunctionLevelDeclContext(); |
| return dyn_cast<FunctionDecl>(DC); |
| } |
| |
| ObjCMethodDecl *Sema::getCurMethodDecl() { |
| DeclContext *DC = getFunctionLevelDeclContext(); |
| return dyn_cast<ObjCMethodDecl>(DC); |
| } |
| |
| NamedDecl *Sema::getCurFunctionOrMethodDecl() { |
| DeclContext *DC = getFunctionLevelDeclContext(); |
| if (isa<ObjCMethodDecl>(DC) || isa<FunctionDecl>(DC)) |
| return cast<NamedDecl>(DC); |
| return 0; |
| } |
| |
| Sema::SemaDiagnosticBuilder::~SemaDiagnosticBuilder() { |
| if (!this->Emit()) |
| return; |
| |
| // If this is not a note, and we're in a template instantiation |
| // that is different from the last template instantiation where |
| // we emitted an error, print a template instantiation |
| // backtrace. |
| if (!SemaRef.Diags.isBuiltinNote(DiagID) && |
| !SemaRef.ActiveTemplateInstantiations.empty() && |
| SemaRef.ActiveTemplateInstantiations.back() |
| != SemaRef.LastTemplateInstantiationErrorContext) { |
| SemaRef.PrintInstantiationStack(); |
| SemaRef.LastTemplateInstantiationErrorContext |
| = SemaRef.ActiveTemplateInstantiations.back(); |
| } |
| } |
| |
| Sema::SemaDiagnosticBuilder |
| Sema::Diag(SourceLocation Loc, const PartialDiagnostic& PD) { |
| SemaDiagnosticBuilder Builder(Diag(Loc, PD.getDiagID())); |
| PD.Emit(Builder); |
| |
| return Builder; |
| } |
| |
| |
| /// \brief Enter a new function scope |
| void Sema::PushFunctionScope() { |
| if (FunctionScopes.empty()) { |
| // Use the "top" function scope rather than having to allocate memory for |
| // a new scope. |
| TopFunctionScope.Clear(getDiagnostics().getNumErrors()); |
| FunctionScopes.push_back(&TopFunctionScope); |
| return; |
| } |
| |
| FunctionScopes.push_back( |
| new FunctionScopeInfo(getDiagnostics().getNumErrors())); |
| } |
| |
| void Sema::PushBlockScope(Scope *BlockScope, BlockDecl *Block) { |
| FunctionScopes.push_back(new BlockScopeInfo(getDiagnostics().getNumErrors(), |
| BlockScope, Block)); |
| } |
| |
| void Sema::PopFunctionOrBlockScope() { |
| if (FunctionScopes.back() != &TopFunctionScope) |
| delete FunctionScopes.back(); |
| else |
| TopFunctionScope.Clear(getDiagnostics().getNumErrors()); |
| |
| FunctionScopes.pop_back(); |
| } |
| |
| /// \brief Determine whether any errors occurred within this function/method/ |
| /// block. |
| bool Sema::hasAnyErrorsInThisFunction() const { |
| unsigned NumErrors = TopFunctionScope.NumErrorsAtStartOfFunction; |
| if (!FunctionScopes.empty()) |
| NumErrors = FunctionScopes.back()->NumErrorsAtStartOfFunction; |
| return NumErrors != getDiagnostics().getNumErrors(); |
| } |
| |
| BlockScopeInfo *Sema::getCurBlock() { |
| if (FunctionScopes.empty()) |
| return 0; |
| |
| return dyn_cast<BlockScopeInfo>(FunctionScopes.back()); |
| } |
| |
| void Sema::ActOnComment(SourceRange Comment) { |
| Context.Comments.push_back(Comment); |
| } |
| |
