| //===--- NameLookup.cpp - Swift Name Lookup Routines ----------------------===// |
| // |
| // This source file is part of the Swift.org open source project |
| // |
| // Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors |
| // Licensed under Apache License v2.0 with Runtime Library Exception |
| // |
| // See https://swift.org/LICENSE.txt for license information |
| // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements interfaces for performing name lookup. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "NameLookupImpl.h" |
| #include "swift/AST/NameLookup.h" |
| #include "swift/AST/AST.h" |
| #include "swift/AST/ASTScope.h" |
| #include "swift/AST/ASTVisitor.h" |
| #include "swift/AST/DebuggerClient.h" |
| #include "swift/AST/LazyResolver.h" |
| #include "swift/AST/Initializer.h" |
| #include "swift/AST/ReferencedNameTracker.h" |
| #include "swift/Basic/Fallthrough.h" |
| #include "swift/Basic/SourceManager.h" |
| #include "swift/Basic/STLExtras.h" |
| #include "llvm/ADT/DenseMap.h" |
| #include "llvm/ADT/TinyPtrVector.h" |
| |
| using namespace swift; |
| |
| void DebuggerClient::anchor() {} |
| |
| void AccessFilteringDeclConsumer::foundDecl(ValueDecl *D, |
| DeclVisibilityKind reason) { |
| if (D->getASTContext().LangOpts.EnableAccessControl) { |
| if (TypeResolver) |
| TypeResolver->resolveAccessibility(D); |
| if (D->isInvalid() && !D->hasAccessibility()) |
| return; |
| if (!D->isAccessibleFrom(DC)) |
| return; |
| } |
| ChainedConsumer.foundDecl(D, reason); |
| } |
| |
| |
| template <typename Fn> |
| static void forAllVisibleModules(const DeclContext *DC, const Fn &fn) { |
| DeclContext *moduleScope = DC->getModuleScopeContext(); |
| if (auto file = dyn_cast<FileUnit>(moduleScope)) |
| file->forAllVisibleModules(fn); |
| else |
| cast<ModuleDecl>(moduleScope)->forAllVisibleModules(ModuleDecl::AccessPathTy(), fn); |
| } |
| |
| bool swift::removeOverriddenDecls(SmallVectorImpl<ValueDecl*> &decls) { |
| if (decls.empty()) |
| return false; |
| |
| ASTContext &ctx = decls.front()->getASTContext(); |
| llvm::SmallPtrSet<ValueDecl*, 8> overridden; |
| for (auto decl : decls) { |
| while (auto overrides = decl->getOverriddenDecl()) { |
| overridden.insert(overrides); |
| |
| // Because initializers from Objective-C base classes have greater |
| // visibility than initializers written in Swift classes, we can |
| // have a "break" in the set of declarations we found, where |
| // C.init overrides B.init overrides A.init, but only C.init and |
| // A.init are in the chain. Make sure we still remove A.init from the |
| // set in this case. |
| if (decl->getFullName().getBaseName() == ctx.Id_init) { |
| /// FIXME: Avoid the possibility of an infinite loop by fixing the root |
| /// cause instead (incomplete circularity detection). |
| assert(decl != overrides && "Circular class inheritance?"); |
| decl = overrides; |
| continue; |
| } |
| |
| break; |
| } |
| } |
| |
| // If no methods were overridden, we're done. |
| if (overridden.empty()) return false; |
| |
| // Erase any overridden declarations |
| bool anyOverridden = false; |
| decls.erase(std::remove_if(decls.begin(), decls.end(), |
| [&](ValueDecl *decl) -> bool { |
| if (overridden.count(decl) > 0) { |
| anyOverridden = true; |
| return true; |
| } |
| |
| return false; |
| }), |
| decls.end()); |
| |
| return anyOverridden; |
| } |
| |
| enum class ConstructorComparison { |
| Worse, |
| Same, |
| Better, |
| }; |
| |
| /// Determines whether \p ctor1 is a "better" initializer than \p ctor2. |
| static ConstructorComparison compareConstructors(ConstructorDecl *ctor1, |
| ConstructorDecl *ctor2, |
| const swift::ASTContext &ctx) { |
| bool available1 = !ctor1->getAttrs().isUnavailable(ctx); |
| bool available2 = !ctor2->getAttrs().isUnavailable(ctx); |
| |
| // An unavailable initializer is always worse than an available initializer. |
| if (available1 < available2) |
| return ConstructorComparison::Worse; |
| |
| if (available1 > available2) |
| return ConstructorComparison::Better; |
| |
| CtorInitializerKind kind1 = ctor1->getInitKind(); |
| CtorInitializerKind kind2 = ctor2->getInitKind(); |
| |
| if (kind1 > kind2) |
| return ConstructorComparison::Worse; |
| |
| if (kind1 < kind2) |
| return ConstructorComparison::Better; |
| |
| return ConstructorComparison::Same; |
| } |
| |
| bool swift::removeShadowedDecls(SmallVectorImpl<ValueDecl*> &decls, |
| const ModuleDecl *curModule, |
| LazyResolver *typeResolver) { |
| // Category declarations by their signatures. |
| llvm::SmallDenseMap<std::pair<CanType, Identifier>, |
| llvm::TinyPtrVector<ValueDecl *>> |
| CollidingDeclGroups; |
| |
| /// Objective-C initializers are tracked by their context type and |
| /// full name. |
| llvm::SmallDenseMap<std::pair<CanType, DeclName>, |
| llvm::TinyPtrVector<ConstructorDecl *>> |
| ObjCCollidingConstructors; |
| bool anyCollisions = false; |
| for (auto decl : decls) { |
| // FIXME: Egregious hack to avoid failing when there are no declared types. |
| // FIXME: Pass this down instead of getting it from the ASTContext. |
| if (typeResolver) |
| typeResolver->resolveDeclSignature(decl); |
| |
| // If the decl is currently being validated, this is likely a recursive |
| // reference and we'll want to skip ahead so as to avoid having its type |
| // attempt to desugar itself. |
| if (!decl->hasValidSignature()) |
| continue; |
| |
| // FIXME: the canonical type makes a poor signature, because we don't |
| // canonicalize away default arguments. |
| auto signature = decl->getInterfaceType()->getCanonicalType(); |
| |
| // FIXME: The type of a variable or subscript doesn't include |
| // enough context to distinguish entities from different |
| // constrained extensions, so use the overload signature's |
| // type. This is layering a partial fix upon a total hack. |
| if (auto asd = dyn_cast<AbstractStorageDecl>(decl)) |
| signature = asd->getOverloadSignature().InterfaceType; |
| |
| // If we've seen a declaration with this signature before, note it. |
| auto &knownDecls = |
| CollidingDeclGroups[std::make_pair(signature, decl->getName())]; |
| if (!knownDecls.empty()) |
| anyCollisions = true; |
| |
| knownDecls.push_back(decl); |
| |
| // Specifically keep track of Objective-C initializers, which can come from |
| // either init methods or factory methods. |
| if (decl->hasClangNode()) { |
| if (auto ctor = dyn_cast<ConstructorDecl>(decl)) { |
| auto ctorSignature |
| = std::make_pair(ctor->getDeclContext()->getDeclaredInterfaceType() |
| ->getCanonicalType(), |
| decl->getFullName()); |
| auto &knownCtors = ObjCCollidingConstructors[ctorSignature]; |
| if (!knownCtors.empty()) |
| anyCollisions = true; |
| knownCtors.push_back(ctor); |
| } |
| } |
| } |
| |
| // If there were no signature collisions, there is nothing to do. |
| if (!anyCollisions) |
| return false; |
| |
| // Determine the set of declarations that are shadowed by other declarations. |
| llvm::SmallPtrSet<ValueDecl *, 4> shadowed; |
| ASTContext &ctx = decls[0]->getASTContext(); |
| for (auto &collidingDecls : CollidingDeclGroups) { |
| // If only one declaration has this signature, it isn't shadowed by |
| // anything. |
| if (collidingDecls.second.size() == 1) |
| continue; |
| |
| // Compare each declaration to every other declaration. This is |
| // unavoidably O(n^2) in the number of declarations, but because they |
| // all have the same signature, we expect n to remain small. |
| for (unsigned firstIdx = 0, n = collidingDecls.second.size(); |
| firstIdx != n; ++firstIdx) { |
| auto firstDecl = collidingDecls.second[firstIdx]; |
| auto firstModule = firstDecl->getModuleContext(); |
| for (unsigned secondIdx = firstIdx + 1; secondIdx != n; ++secondIdx) { |
| // Determine whether one module takes precedence over another. |
| auto secondDecl = collidingDecls.second[secondIdx]; |
| auto secondModule = secondDecl->getModuleContext(); |
| |
| // If one declaration is in a protocol or extension thereof and the |
| // other is not, prefer the one that is not. |
| if ((bool)firstDecl->getDeclContext() |
| ->getAsProtocolOrProtocolExtensionContext() |
| != (bool)secondDecl->getDeclContext() |
| ->getAsProtocolOrProtocolExtensionContext()) { |
| if (firstDecl->getDeclContext() |
| ->getAsProtocolOrProtocolExtensionContext()) { |
| shadowed.insert(firstDecl); |
| break; |
| } else { |
| shadowed.insert(secondDecl); |
| continue; |
| } |
| } |
| |
| // If one declaration is available and the other is not, prefer the |
| // available one. |
| if (firstDecl->getAttrs().isUnavailable(ctx) != |
| secondDecl->getAttrs().isUnavailable(ctx)) { |
| if (firstDecl->getAttrs().isUnavailable(ctx)) { |
| shadowed.insert(firstDecl); |
| break; |
| } else { |
| shadowed.insert(secondDecl); |
| continue; |
| } |
| } |
| |
| // Don't apply module-shadowing rules to members of protocol types. |
| if (isa<ProtocolDecl>(firstDecl->getDeclContext()) || |
| isa<ProtocolDecl>(secondDecl->getDeclContext())) |
| continue; |
| |
| // Prefer declarations in the current module over those in another |
| // module. |
| // FIXME: This is a hack. We should query a (lazily-built, cached) |
| // module graph to determine shadowing. |
| if ((firstModule == curModule) == (secondModule == curModule)) |
| continue; |
| |
| // If the first module is the current module, the second declaration |
| // is shadowed by the first. |
| if (firstModule == curModule) { |
| shadowed.insert(secondDecl); |
| continue; |
| } |
| |
| // Otherwise, the first declaration is shadowed by the second. There is |
| // no point in continuing to compare the first declaration to others. |
| shadowed.insert(firstDecl); |
| break; |
| } |
| } |
| } |
| |
| // Check for collisions among Objective-C initializers. When such collisions |
| // exist, we pick the |
| for (const auto &colliding : ObjCCollidingConstructors) { |
| if (colliding.second.size() == 1) |
| continue; |
| |
| // Find the "best" constructor with this signature. |
| ConstructorDecl *bestCtor = colliding.second[0]; |
| for (auto ctor : colliding.second) { |
| auto comparison = compareConstructors(ctor, bestCtor, ctx); |
| if (comparison == ConstructorComparison::Better) |
| bestCtor = ctor; |
| } |
| |
| // Shadow any initializers that are worse. |
| for (auto ctor : colliding.second) { |
| auto comparison = compareConstructors(ctor, bestCtor, ctx); |
| if (comparison == ConstructorComparison::Worse) |
| shadowed.insert(ctor); |
| } |
| } |
| |
| // If none of the declarations were shadowed, we're done. |
| if (shadowed.empty()) |
| return false; |
| |
| // Remove shadowed declarations from the list of declarations. |
| bool anyRemoved = false; |
| decls.erase(std::remove_if(decls.begin(), decls.end(), |
| [&](ValueDecl *vd) { |
| if (shadowed.count(vd) > 0) { |
| anyRemoved = true; |
| return true; |
| } |
| |
| return false; |
| }), |
| decls.end()); |
| |
| return anyRemoved; |
| } |
| |
| namespace { |
| enum class DiscriminatorMatch { |
| NoDiscriminator, |
| Matches, |
| Different |
| }; |
| } // end anonymous namespace |
| |
| static DiscriminatorMatch matchDiscriminator(Identifier discriminator, |
| const ValueDecl *value) { |
| if (value->getFormalAccess() > Accessibility::FilePrivate) |
| return DiscriminatorMatch::NoDiscriminator; |
| |
| auto containingFile = |
| dyn_cast<FileUnit>(value->getDeclContext()->getModuleScopeContext()); |
| if (!containingFile) |
| return DiscriminatorMatch::Different; |
| |
| if (discriminator == containingFile->getDiscriminatorForPrivateValue(value)) |
| return DiscriminatorMatch::Matches; |
| |
| return DiscriminatorMatch::Different; |
| } |
| |
| static DiscriminatorMatch |
| matchDiscriminator(Identifier discriminator, |
| UnqualifiedLookupResult lookupResult) { |
| return matchDiscriminator(discriminator, lookupResult.getValueDecl()); |
| } |
| |
| template <typename Result> |
| static void filterForDiscriminator(SmallVectorImpl<Result> &results, |
| DebuggerClient *debugClient) { |
| Identifier discriminator = debugClient->getPreferredPrivateDiscriminator(); |
| if (discriminator.empty()) |
| return; |
| |
| auto lastMatchIter = std::find_if(results.rbegin(), results.rend(), |
| [discriminator](Result next) -> bool { |
| return |
| matchDiscriminator(discriminator, next) == DiscriminatorMatch::Matches; |
| }); |
| if (lastMatchIter == results.rend()) |
| return; |
| |
| Result lastMatch = *lastMatchIter; |
| |
| auto newEnd = std::remove_if(results.begin(), lastMatchIter.base()-1, |
| [discriminator](Result next) -> bool { |
| return |
| matchDiscriminator(discriminator, next) == DiscriminatorMatch::Different; |
| }); |
| results.erase(newEnd, results.end()); |
| results.push_back(lastMatch); |
| } |
| |
| static void recordLookupOfTopLevelName(DeclContext *topLevelContext, |
| DeclName name, |
| bool isCascading) { |
| auto SF = dyn_cast<SourceFile>(topLevelContext); |
| if (!SF) |
| return; |
| auto *nameTracker = SF->getReferencedNameTracker(); |
| if (!nameTracker) |
| return; |
| nameTracker->addTopLevelName(name.getBaseName(), isCascading); |
| } |
| |
| /// Determine the local declaration visibility key for an \c ASTScope in which |
| /// name lookup successfully resolved. |
| static DeclVisibilityKind getLocalDeclVisibilityKind(const ASTScope *scope) { |
| switch (scope->getKind()) { |
| case ASTScopeKind::Preexpanded: |
| case ASTScopeKind::SourceFile: |
| case ASTScopeKind::TypeDecl: |
| case ASTScopeKind::AbstractFunctionDecl: |
| case ASTScopeKind::TypeOrExtensionBody: |
| case ASTScopeKind::AbstractFunctionBody: |
| case ASTScopeKind::DefaultArgument: |
| case ASTScopeKind::PatternBinding: |
| case ASTScopeKind::IfStmt: |
| case ASTScopeKind::GuardStmt: |
| case ASTScopeKind::RepeatWhileStmt: |
| case ASTScopeKind::ForEachStmt: |
| case ASTScopeKind::DoCatchStmt: |
| case ASTScopeKind::SwitchStmt: |
| case ASTScopeKind::ForStmt: |
| case ASTScopeKind::Accessors: |
| case ASTScopeKind::TopLevelCode: |
| llvm_unreachable("no local declarations?"); |
| |
| case ASTScopeKind::ExtensionGenericParams: |
| case ASTScopeKind::GenericParams: |
| return DeclVisibilityKind::GenericParameter; |
| |
| case ASTScopeKind::AbstractFunctionParams: |
| case ASTScopeKind::Closure: |
| case ASTScopeKind::PatternInitializer: // lazy var 'self' |
| return DeclVisibilityKind::FunctionParameter; |
| |
| case ASTScopeKind::AfterPatternBinding: |
| case ASTScopeKind::ConditionalClause: |
| case ASTScopeKind::ForEachPattern: |
| case ASTScopeKind::BraceStmt: |
| case ASTScopeKind::CatchStmt: |
| case ASTScopeKind::CaseStmt: |
| case ASTScopeKind::ForStmtInitializer: |
| return DeclVisibilityKind::LocalVariable; |
| } |
| |
| llvm_unreachable("Unhandled ASTScopeKind in switch."); |
| } |
| |
| UnqualifiedLookup::UnqualifiedLookup(DeclName Name, DeclContext *DC, |
| LazyResolver *TypeResolver, |
| bool IsKnownNonCascading, |
| SourceLoc Loc, bool IsTypeLookup, |
| bool AllowProtocolMembers, |
| bool IgnoreAccessControl) { |
| ModuleDecl &M = *DC->getParentModule(); |
| ASTContext &Ctx = M.getASTContext(); |
| const SourceManager &SM = Ctx.SourceMgr; |
| DebuggerClient *DebugClient = M.getDebugClient(); |
| |
| NamedDeclConsumer Consumer(Name, Results, IsTypeLookup); |
| |
| Optional<bool> isCascadingUse; |
| if (IsKnownNonCascading) |
| isCascadingUse = false; |
| |
| SmallVector<UnqualifiedLookupResult, 4> UnavailableInnerResults; |
| |
| if (Loc.isValid() && |
| DC->getParentSourceFile()->Kind != SourceFileKind::REPL && |
| Ctx.LangOpts.EnableASTScopeLookup) { |
| // Find the source file in which we are performing the lookup. |
| SourceFile &sourceFile = *DC->getParentSourceFile(); |
| |
| // Find the scope from which we will initiate unqualified name lookup. |
| const ASTScope *lookupScope |
| = sourceFile.getScope().findInnermostEnclosingScope(Loc); |
| |
| // Operator lookup is always at module scope. |
| if (Name.isOperator()) { |
| if (!isCascadingUse.hasValue()) { |
| DeclContext *innermostDC = |
| lookupScope->getInnermostEnclosingDeclContext(); |
| isCascadingUse = |
| innermostDC->isCascadingContextForLookup( |
| /*functionsAreNonCascading=*/true); |
| } |
| |
| lookupScope = &sourceFile.getScope(); |
| } |
| |
| // Walk scopes outward from the innermost scope until we find something. |
| ParamDecl *selfDecl = nullptr; |
| for (auto currentScope = lookupScope; currentScope; |
| currentScope = currentScope->getParent()) { |
| // Perform local lookup within this scope. |
| auto localBindings = currentScope->getLocalBindings(); |
| for (auto local : localBindings) { |
| Consumer.foundDecl(local, |
| getLocalDeclVisibilityKind(currentScope)); |
| } |
| |
| // If we found anything, we're done. |
| if (!Results.empty()) |
| return; |
| |
| // When we are in the body of a method, get the 'self' declaration. |
| if (currentScope->getKind() == ASTScopeKind::AbstractFunctionBody && |
| currentScope->getAbstractFunctionDecl()->getDeclContext() |
| ->isTypeContext()) { |
| selfDecl = |
| currentScope->getAbstractFunctionDecl()->getImplicitSelfDecl(); |
| continue; |
| } |
| |
| // If there is a declaration context associated with this scope, we might |
| // want to look in it. |
| if (auto dc = currentScope->getDeclContext()) { |
| // If we haven't determined whether we have a cascading use, do so now. |
| if (!isCascadingUse.hasValue()) { |
| isCascadingUse = |
| dc->isCascadingContextForLookup(/*functionsAreNonCascading=*/false); |
| } |
| |
| // Pattern binding initializers are only interesting insofar as they |
| // affect lookup in an enclosing nominal type or extension thereof. |
| if (auto *bindingInit = dyn_cast<PatternBindingInitializer>(dc)) { |
| if (auto binding = bindingInit->getBinding()) { |
| // Look for 'self' for a lazy variable initializer. |
| if (auto singleVar = binding->getSingleVar()) |
| // We only care about lazy variables. |
| if (singleVar->getAttrs().hasAttribute<LazyAttr>()) { |
| |
| // 'self' will be listed in the local bindings. |
| for (auto local : localBindings) { |
| auto param = dyn_cast<ParamDecl>(local); |
| if (!param) continue; |
| |
| |
| // If we have a variable that's the implicit self of its enclosing |
| // context, mark it as 'self'. |
| if (auto func = dyn_cast<FuncDecl>(param->getDeclContext())) { |
| if (param == func->getImplicitSelfDecl()) { |
| selfDecl = param; |
| break; |
| } |
| } |
| } |
| } |
| } |
| continue; |
| } |
| |
| // Default arguments only have 'static' access to the members of the |
| // enclosing type, if there is one. |
| if (isa<DefaultArgumentInitializer>(dc)) continue; |
| |
| // Functions/initializers/deinitializers are only interesting insofar as |
| // they affect lookup in an enclosing nominal type or extension thereof. |
| if (isa<AbstractFunctionDecl>(dc)) continue; |
| |
| // Subscripts have no lookup of their own. |
| if (isa<SubscriptDecl>(dc)) continue; |
| |
| // Closures have no lookup of their own. |
| if (isa<AbstractClosureExpr>(dc)) continue; |
| |
| // Top-level declarations have no lookup of their own. |
| if (isa<TopLevelCodeDecl>(dc)) continue; |
| |
| // Typealiases have no lookup of their own. |
| if (isa<TypeAliasDecl>(dc)) continue; |
| |
| // Lookup in the source file's scope marks the end. |
| if (isa<SourceFile>(dc)) { |
| // FIXME: A bit of a hack. |
| DC = dc; |
| break; |
| } |
| |
| // We have a nominal type or an extension thereof. Perform lookup into |
| // the nominal type. |
| auto nominal = dc->getAsNominalTypeOrNominalTypeExtensionContext(); |
| if (!nominal) continue; |
| |
| // FIXME: This is overkill for name lookup. |
| if (TypeResolver) |
| TypeResolver->resolveDeclSignature(nominal); |
| |
| // Dig out the type we're looking into. |
| // FIXME: We shouldn't need to compute a type to perform this lookup. |
| Type lookupType = dc->getSelfTypeInContext(); |
| |
| // FIXME: Hack to deal with missing 'Self' archetypes. |
| if (!lookupType) { |
| if (auto proto = dc->getAsProtocolOrProtocolExtensionContext()) |
| lookupType = proto->getDeclaredType(); |
| } |
| |
| if (!lookupType || lookupType->hasError()) continue; |
| |
| // Perform lookup into the type. |
| NLOptions options = NL_UnqualifiedDefault; |
| if (isCascadingUse.getValue()) |
| options |= NL_KnownCascadingDependency; |
| else |
| options |= NL_KnownNonCascadingDependency; |
| |
| if (AllowProtocolMembers) |
| options |= NL_ProtocolMembers; |
| if (IsTypeLookup) |
| options |= NL_OnlyTypes; |
| if (IgnoreAccessControl) |
| options |= NL_IgnoreAccessibility; |
| |
| SmallVector<ValueDecl *, 4> lookup; |
| dc->lookupQualified(lookupType, Name, options, TypeResolver, lookup); |
| ValueDecl *baseDecl = nominal; |
| if (selfDecl) baseDecl = selfDecl; |
| for (auto result : lookup) { |
| Results.push_back(UnqualifiedLookupResult(baseDecl, result)); |
| } |
| |
| if (!Results.empty()) { |
| // Predicate that determines whether a lookup result should |
| // be unavailable except as a last-ditch effort. |
| auto unavailableLookupResult = |
| [&](const UnqualifiedLookupResult &result) { |
| return result.getValueDecl()->getAttrs() |
| .isUnavailableInSwiftVersion(); |
| }; |
| |
| // If all of the results we found are unavailable, keep looking. |
| if (std::all_of(Results.begin(), Results.end(), |
| unavailableLookupResult)) { |
| UnavailableInnerResults.append(Results.begin(), Results.end()); |
| Results.clear(); |
| } else { |
| if (DebugClient) |
| filterForDiscriminator(Results, DebugClient); |
| return; |
| } |
| } |
| |
| // Forget the 'self' declaration. |
| selfDecl = nullptr; |
| } |
| } |
| } else { |
| // Never perform local lookup for operators. |
| if (Name.isOperator()) { |
| if (!isCascadingUse.hasValue()) { |
| isCascadingUse = |
| DC->isCascadingContextForLookup(/*functionsAreNonCascading=*/true); |
| } |
| DC = DC->getModuleScopeContext(); |
| |
| } else { |
| // If we are inside of a method, check to see if there are any ivars in |
| // scope, and if so, whether this is a reference to one of them. |
| // FIXME: We should persist this information between lookups. |
| while (!DC->isModuleScopeContext()) { |
| ValueDecl *BaseDecl = nullptr; |
| ValueDecl *MetaBaseDecl = nullptr; |
| GenericParamList *GenericParams = nullptr; |
| Type ExtendedType; |
| bool isTypeLookup = false; |
| |
| // If this declcontext is an initializer for a static property, then we're |
| // implicitly doing a static lookup into the parent declcontext. |
| if (auto *PBI = dyn_cast<PatternBindingInitializer>(DC)) |
| if (!DC->getParent()->isModuleScopeContext()) { |
| if (auto *PBD = PBI->getBinding()) { |
| isTypeLookup = PBD->isStatic(); |
| DC = DC->getParent(); |
| } |
| } |
| |
| if (auto *AFD = dyn_cast<AbstractFunctionDecl>(DC)) { |
| // Look for local variables; normally, the parser resolves these |
| // for us, but it can't do the right thing inside local types. |
| // FIXME: when we can parse and typecheck the function body partially |
| // for code completion, AFD->getBody() check can be removed. |
| if (Loc.isValid() && AFD->getBody()) { |
| if (!isCascadingUse.hasValue()) { |
| isCascadingUse = |
| !SM.rangeContainsTokenLoc(AFD->getBodySourceRange(), Loc); |
| } |
| |
| namelookup::FindLocalVal localVal(SM, Loc, Consumer); |
| localVal.visit(AFD->getBody()); |
| if (!Results.empty()) |
| return; |
| for (auto *PL : AFD->getParameterLists()) |
| localVal.checkParameterList(PL); |
| if (!Results.empty()) |
| return; |
| } |
| if (!isCascadingUse.hasValue() || isCascadingUse.getValue()) |
| isCascadingUse = AFD->isCascadingContextForLookup(false); |
| |
| if (AFD->getDeclContext()->isTypeContext()) { |
| ExtendedType = AFD->getDeclContext()->getSelfTypeInContext(); |
| // FIXME: Hack to deal with missing 'Self' archetypes. |
| if (!ExtendedType) |
| if (auto *PD = AFD->getDeclContext() |
| ->getAsProtocolOrProtocolExtensionContext()) |
| ExtendedType = PD->getDeclaredType(); |
| |
| BaseDecl = AFD->getImplicitSelfDecl(); |
| MetaBaseDecl = AFD->getDeclContext() |
| ->getAsNominalTypeOrNominalTypeExtensionContext(); |
| DC = DC->getParent(); |
| |
| if (auto *FD = dyn_cast<FuncDecl>(AFD)) |
| if (FD->isStatic()) |
| isTypeLookup = true; |
| |
| // If we're not in the body of the function, the base declaration |
| // is the nominal type, not 'self'. |
| if (Loc.isValid() && |
| AFD->getBodySourceRange().isValid() && |
| !SM.rangeContainsTokenLoc(AFD->getBodySourceRange(), Loc)) { |
| BaseDecl = MetaBaseDecl; |
| } |
| } |
| |
| // Look in the generic parameters after checking our local declaration. |
| GenericParams = AFD->getGenericParams(); |
| } else if (auto *ACE = dyn_cast<AbstractClosureExpr>(DC)) { |
| // Look for local variables; normally, the parser resolves these |
| // for us, but it can't do the right thing inside local types. |
| if (Loc.isValid()) { |
| if (auto *CE = dyn_cast<ClosureExpr>(ACE)) { |
| namelookup::FindLocalVal localVal(SM, Loc, Consumer); |
| localVal.visit(CE->getBody()); |
| if (!Results.empty()) |
| return; |
| localVal.checkParameterList(CE->getParameters()); |
| if (!Results.empty()) |
| return; |
| } |
| } |
| if (!isCascadingUse.hasValue()) |
| isCascadingUse = ACE->isCascadingContextForLookup(false); |
| } else if (ExtensionDecl *ED = dyn_cast<ExtensionDecl>(DC)) { |
| ExtendedType = ED->getSelfTypeInContext(); |
| |
| BaseDecl = ED->getAsNominalTypeOrNominalTypeExtensionContext(); |
| MetaBaseDecl = BaseDecl; |
| if (!isCascadingUse.hasValue()) |
| isCascadingUse = ED->isCascadingContextForLookup(false); |
| } else if (NominalTypeDecl *ND = dyn_cast<NominalTypeDecl>(DC)) { |
| ExtendedType = ND->getDeclaredType(); |
| BaseDecl = ND; |
| MetaBaseDecl = BaseDecl; |
| if (!isCascadingUse.hasValue()) |
| isCascadingUse = ND->isCascadingContextForLookup(false); |
| } else if (auto I = dyn_cast<DefaultArgumentInitializer>(DC)) { |
| // In a default argument, skip immediately out of both the |
| // initializer and the function. |
| isCascadingUse = false; |
| DC = I->getParent()->getParent(); |
| continue; |
| } else { |
| assert(isa<TopLevelCodeDecl>(DC) || isa<Initializer>(DC) || |
| isa<TypeAliasDecl>(DC)); |
| if (!isCascadingUse.hasValue()) |
| isCascadingUse = DC->isCascadingContextForLookup(false); |
| } |
| |
| // Check the generic parameters for something with the given name. |
| if (GenericParams) { |
| namelookup::FindLocalVal localVal(SM, Loc, Consumer); |
| localVal.checkGenericParams(GenericParams); |
| |
| if (!Results.empty()) |
| return; |
| } |
| |
| if (BaseDecl) { |
| if (TypeResolver) |
| TypeResolver->resolveDeclSignature(BaseDecl); |
| |
| NLOptions options = NL_UnqualifiedDefault; |
| if (isCascadingUse.getValue()) |
| options |= NL_KnownCascadingDependency; |
| else |
| options |= NL_KnownNonCascadingDependency; |
| |
| if (AllowProtocolMembers) |
| options |= NL_ProtocolMembers; |
| if (IsTypeLookup) |
| options |= NL_OnlyTypes; |
| if (IgnoreAccessControl) |
| options |= NL_IgnoreAccessibility; |
| |
| if (!ExtendedType) |
| ExtendedType = ErrorType::get(Ctx); |
| |
| SmallVector<ValueDecl *, 4> Lookup; |
| DC->lookupQualified(ExtendedType, Name, options, TypeResolver, Lookup); |
| bool FoundAny = false; |
| for (auto Result : Lookup) { |
| // In Swift 3 mode, unqualified lookup skips static methods when |
| // performing lookup from instance context. |
| // |
| // We don't want to carry this forward to Swift 4, since it makes |
| // for poor diagnostics. |
| // |
| // Also, it was quite a special case and not as general as it |
| // should be -- it didn't apply to properties or subscripts, and |
| // the opposite case where we're in static context and an instance |
| // member shadows the module member wasn't handled either. |
| if (Ctx.isSwiftVersion3() && |
| !isTypeLookup && |
| isa<FuncDecl>(Result) && |
| cast<FuncDecl>(Result)->isStatic()) { |
| continue; |
| } |
| |
| // Classify this declaration. |
| FoundAny = true; |
| |
| // Types are local or metatype members. |
| if (auto TD = dyn_cast<TypeDecl>(Result)) { |
| if (isa<GenericTypeParamDecl>(TD)) |
| Results.push_back(UnqualifiedLookupResult(Result)); |
| else |
| Results.push_back(UnqualifiedLookupResult(MetaBaseDecl, Result)); |
| continue; |
| } |
| |
| Results.push_back(UnqualifiedLookupResult(BaseDecl, Result)); |
| } |
| |
| if (FoundAny) { |
| // Predicate that determines whether a lookup result should |
| // be unavailable except as a last-ditch effort. |
| auto unavailableLookupResult = |
| [&](const UnqualifiedLookupResult &result) { |
| return result.getValueDecl()->getAttrs() |
| .isUnavailableInSwiftVersion(); |
| }; |
| |
| // If all of the results we found are unavailable, keep looking. |
| if (std::all_of(Results.begin(), Results.end(), |
| unavailableLookupResult)) { |
| UnavailableInnerResults.append(Results.begin(), Results.end()); |
| Results.clear(); |
| FoundAny = false; |
| } else { |
| if (DebugClient) |
| filterForDiscriminator(Results, DebugClient); |
| return; |
| } |
| } |
| |
| // Check the generic parameters if our context is a generic type or |
| // extension thereof. |
| GenericParamList *dcGenericParams = nullptr; |
| if (auto nominal = dyn_cast<NominalTypeDecl>(DC)) |
| dcGenericParams = nominal->getGenericParams(); |
| else if (auto ext = dyn_cast<ExtensionDecl>(DC)) |
| dcGenericParams = ext->getGenericParams(); |
| |
| while (dcGenericParams) { |
| namelookup::FindLocalVal localVal(SM, Loc, Consumer); |
| localVal.checkGenericParams(dcGenericParams); |
| |
| if (!Results.empty()) |
| return; |
| |
| if (!isa<ExtensionDecl>(DC)) |
| break; |
| |
| dcGenericParams = dcGenericParams->getOuterParameters(); |
| } |
| } |
| |
| DC = DC->getParent(); |
| } |
| |
| if (!isCascadingUse.hasValue()) |
| isCascadingUse = true; |
| } |
| |
| if (auto SF = dyn_cast<SourceFile>(DC)) { |
| if (Loc.isValid()) { |
| // Look for local variables in top-level code; normally, the parser |
| // resolves these for us, but it can't do the right thing for |
| // local types. |
| namelookup::FindLocalVal localVal(SM, Loc, Consumer); |
| localVal.checkSourceFile(*SF); |
| if (!Results.empty()) |
| return; |
| } |
| } |
| } |
| |
| // TODO: Does the debugger client care about compound names? |
| if (Name.isSimpleName() |
| && DebugClient && DebugClient->lookupOverrides(Name.getBaseName(), DC, |
| Loc, IsTypeLookup, Results)) |
| return; |
| |
| recordLookupOfTopLevelName(DC, Name, isCascadingUse.getValue()); |
| |
| // Add private imports to the extra search list. |
| SmallVector<ModuleDecl::ImportedModule, 8> extraImports; |
| if (auto FU = dyn_cast<FileUnit>(DC)) |
| FU->getImportedModules(extraImports, ModuleDecl::ImportFilter::Private); |
| |
| using namespace namelookup; |
| SmallVector<ValueDecl *, 8> CurModuleResults; |
| auto resolutionKind = |
| IsTypeLookup ? ResolutionKind::TypesOnly : ResolutionKind::Overloadable; |
| lookupInModule(&M, {}, Name, CurModuleResults, NLKind::UnqualifiedLookup, |
| resolutionKind, TypeResolver, DC, extraImports); |
| |
| for (auto VD : CurModuleResults) |
| Results.push_back(UnqualifiedLookupResult(VD)); |
| |
| if (DebugClient) |
| filterForDiscriminator(Results, DebugClient); |
| |
| // Now add any names the DebugClient knows about to the lookup. |
| if (Name.isSimpleName() && DebugClient) |
| DebugClient->lookupAdditions(Name.getBaseName(), DC, Loc, IsTypeLookup, |
| Results); |
| |
| // If we've found something, we're done. |
| if (!Results.empty()) |
| return; |
| |
| // If we still haven't found anything, but we do have some |
| // declarations that are "unavailable in the current Swift", drop |
| // those in. |
| if (!UnavailableInnerResults.empty()) { |
| Results = std::move(UnavailableInnerResults); |
| return; |
| } |
| |
| if (!Name.isSimpleName()) |
| return; |
| |
| // Look for a module with the given name. |
| if (Name.isSimpleName(M.getName())) { |
| Results.push_back(UnqualifiedLookupResult(&M)); |
| return; |
| } |
| |
| ModuleDecl *desiredModule = Ctx.getLoadedModule(Name.getBaseName()); |
| if (!desiredModule && Name == Ctx.TheBuiltinModule->getName()) |
| desiredModule = Ctx.TheBuiltinModule; |
| if (desiredModule) { |
| forAllVisibleModules(DC, [&](const ModuleDecl::ImportedModule &import) -> bool { |
| if (import.second == desiredModule) { |
| Results.push_back(UnqualifiedLookupResult(import.second)); |
| return false; |
| } |
| return true; |
| }); |
| } |
| } |
| |
| TypeDecl* UnqualifiedLookup::getSingleTypeResult() { |
| if (Results.size() != 1) |
| return nullptr; |
| return dyn_cast<TypeDecl>(Results.back().getValueDecl()); |
| } |
| |
| #pragma mark Member lookup table |
| |
| void LazyMemberLoader::anchor() {} |
| |
| /// Lookup table used to store members of a nominal type (and its extensions) |
| /// for fast retrieval. |
| class swift::MemberLookupTable { |
| /// The last extension that was included within the member lookup table's |
| /// results. |
| ExtensionDecl *LastExtensionIncluded = nullptr; |
| |
| /// The type of the internal lookup table. |
| typedef llvm::DenseMap<DeclName, llvm::TinyPtrVector<ValueDecl *>> |
| LookupTable; |
| |
| /// Lookup table mapping names to the set of declarations with that name. |
| LookupTable Lookup; |
| |
| public: |
| /// Create a new member lookup table. |
| explicit MemberLookupTable(ASTContext &ctx); |
| |
| /// Destroy the lookup table. |
| void destroy(); |
| |
| /// Update a lookup table with members from newly-added extensions. |
| void updateLookupTable(NominalTypeDecl *nominal); |
| |
| /// \brief Add the given member to the lookup table. |
| void addMember(Decl *members); |
| |
| /// \brief Add the given members to the lookup table. |
| void addMembers(DeclRange members); |
| |
| /// \brief The given extension has been extended with new members; add them |
| /// if appropriate. |
| void addExtensionMembers(NominalTypeDecl *nominal, |
| ExtensionDecl *ext, |
| DeclRange members); |
| |
| /// Iterator into the lookup table. |
| typedef LookupTable::iterator iterator; |
| |
| iterator begin() { return Lookup.begin(); } |
| iterator end() { return Lookup.end(); } |
| |
| iterator find(DeclName name) { |
| return Lookup.find(name); |
| } |
| |
| // Only allow allocation of member lookup tables using the allocator in |
| // ASTContext or by doing a placement new. |
| void *operator new(size_t Bytes, ASTContext &C, |
| unsigned Alignment = alignof(MemberLookupTable)) { |
| return C.Allocate(Bytes, Alignment); |
| } |
| void *operator new(size_t Bytes, void *Mem) { |
| assert(Mem); |
| return Mem; |
| } |
| }; |
| |
| namespace { |
| /// Stores the set of Objective-C methods with a given selector within the |
| /// Objective-C method lookup table. |
| struct StoredObjCMethods { |
| /// The generation count at which this list was last updated. |
| unsigned Generation = 0; |
| |
| /// The set of methods with the given selector. |
| llvm::TinyPtrVector<AbstractFunctionDecl *> Methods; |
| }; |
| } // end anonymous namespace |
| |
| /// Class member lookup table, which is a member lookup table with a second |
| /// table for lookup based on Objective-C selector. |
| class ClassDecl::ObjCMethodLookupTable |
| : public llvm::DenseMap<std::pair<ObjCSelector, char>, |
| StoredObjCMethods> |
| { |
| public: |
| void destroy() { |
| this->~ObjCMethodLookupTable(); |
| } |
| |
| // Only allow allocation of member lookup tables using the allocator in |
| // ASTContext or by doing a placement new. |
| void *operator new(size_t Bytes, ASTContext &C, |
| unsigned Alignment = alignof(MemberLookupTable)) { |
| return C.Allocate(Bytes, Alignment); |
| } |
| void *operator new(size_t Bytes, void *Mem) { |
| assert(Mem); |
| return Mem; |
| } |
| }; |
| |
| MemberLookupTable::MemberLookupTable(ASTContext &ctx) { |
| // Register a cleanup with the ASTContext to call the lookup table |
| // destructor. |
| ctx.addCleanup([this]() { |
| this->destroy(); |
| }); |
| } |
| |
| void MemberLookupTable::addMember(Decl *member) { |
| // Only value declarations matter. |
| auto vd = dyn_cast<ValueDecl>(member); |
| if (!vd) |
| return; |
| |
| // Unnamed entities cannot be found by name lookup. |
| if (!vd->hasName()) |
| return; |
| |
| // If this declaration is already in the lookup table, don't add it |
| // again. |
| if (vd->ValueDeclBits.AlreadyInLookupTable) { |
| return; |
| } |
| vd->ValueDeclBits.AlreadyInLookupTable = true; |
| |
| // Add this declaration to the lookup set under its compound name and simple |
| // name. |
| vd->getFullName().addToLookupTable(Lookup, vd); |
| } |
| |
| void MemberLookupTable::addMembers(DeclRange members) { |
| for (auto member : members) { |
| addMember(member); |
| } |
| } |
| |
| void MemberLookupTable::addExtensionMembers(NominalTypeDecl *nominal, |
| ExtensionDecl *ext, |
| DeclRange members) { |
| // We have not processed any extensions yet, so there's nothing to do. |
| if (!LastExtensionIncluded) |
| return; |
| |
| // If this extension shows up in the list of extensions not yet included |
| // in the lookup table, there's nothing to do. |
| for (auto notIncluded = LastExtensionIncluded->NextExtension.getPointer(); |
| notIncluded; |
| notIncluded = notIncluded->NextExtension.getPointer()) { |
| if (notIncluded == ext) |
| return; |
| } |
| |
| // Add the new members to the lookup table. |
| addMembers(members); |
| } |
| |
| void MemberLookupTable::updateLookupTable(NominalTypeDecl *nominal) { |
| // If the last extension we included is the same as the last known extension, |
| // we're already up-to-date. |
| if (LastExtensionIncluded == nominal->LastExtension) |
| return; |
| |
| // Add members from each of the extensions that we have not yet visited. |
| for (auto next = LastExtensionIncluded |
| ? LastExtensionIncluded->NextExtension.getPointer() |
| : nominal->FirstExtension; |
| next; |
| (LastExtensionIncluded = next,next = next->NextExtension.getPointer())) { |
| addMembers(next->getMembers()); |
| } |
| } |
| |
| void MemberLookupTable::destroy() { |
| this->~MemberLookupTable(); |
| } |
| |
| void NominalTypeDecl::addedMember(Decl *member) { |
| // If we have a lookup table, add the new member to it. |
| if (LookupTable.getPointer()) { |
| LookupTable.getPointer()->addMember(member); |
| } |
| } |
| |
| void ExtensionDecl::addedMember(Decl *member) { |
| if (NextExtension.getInt()) { |
| if (getExtendedType()->hasError()) |
| return; |
| |
| auto nominal = getExtendedType()->getAnyNominal(); |
| if (nominal->LookupTable.getPointer()) { |
| // Make sure we have the complete list of extensions. |
| // FIXME: This is completely unnecessary. We want to determine whether |
| // our own extension has already been included in the lookup table. |
| (void)nominal->getExtensions(); |
| |
| nominal->LookupTable.getPointer()->addMember(member); |
| } |
| } |
| } |
| |
| void NominalTypeDecl::prepareLookupTable(bool ignoreNewExtensions) { |
| // If we haven't allocated the lookup table yet, do so now. |
| if (!LookupTable.getPointer()) { |
| auto &ctx = getASTContext(); |
| LookupTable.setPointer(new (ctx) MemberLookupTable(ctx)); |
| } |
| |
| // If we haven't walked the member list yet to update the lookup |
| // table, do so now. |
| if (!LookupTable.getInt()) { |
| // Note that we'll have walked the members now. |
| LookupTable.setInt(true); |
| |
| // Add the members of the nominal declaration to the table. |
| LookupTable.getPointer()->addMembers(getMembers()); |
| } |
| |
| if (!ignoreNewExtensions) { |
| // Update the lookup table to introduce members from extensions. |
| LookupTable.getPointer()->updateLookupTable(this); |
| } |
| } |
| |
| void NominalTypeDecl::makeMemberVisible(ValueDecl *member) { |
| if (!LookupTable.getPointer()) { |
| auto &ctx = getASTContext(); |
| LookupTable.setPointer(new (ctx) MemberLookupTable(ctx)); |
| } |
| |
| LookupTable.getPointer()->addMember(member); |
| } |
| |
| ArrayRef<ValueDecl *> NominalTypeDecl::lookupDirect(DeclName name, |
| bool ignoreNewExtensions) { |
| // Make sure we have the complete list of members (in this nominal and in all |
| // extensions). |
| if (!ignoreNewExtensions) { |
| for (auto E : getExtensions()) |
| (void)E->getMembers(); |
| } |
| |
| (void)getMembers(); |
| |
| prepareLookupTable(ignoreNewExtensions); |
| |
| // Look for the declarations with this name. |
| auto known = LookupTable.getPointer()->find(name); |
| if (known == LookupTable.getPointer()->end()) |
| return { }; |
| |
| // We found something; return it. |
| return { known->second.begin(), known->second.size() }; |
| } |
| |
| void ClassDecl::createObjCMethodLookup() { |
| assert(!ObjCMethodLookup && "Already have an Objective-C member table"); |
| auto &ctx = getASTContext(); |
| ObjCMethodLookup = new (ctx) ObjCMethodLookupTable(); |
| |
| // Register a cleanup with the ASTContext to call the lookup table |
| // destructor. |
| ctx.addCleanup([this]() { |
| this->ObjCMethodLookup->destroy(); |
| }); |
| } |
| |
| MutableArrayRef<AbstractFunctionDecl *> |
| ClassDecl::lookupDirect(ObjCSelector selector, bool isInstance) { |
| if (!ObjCMethodLookup) { |
| createObjCMethodLookup(); |
| } |
| |
| // If any modules have been loaded since we did the search last (or if we |
| // hadn't searched before), look in those modules, too. |
| auto &stored = (*ObjCMethodLookup)[{selector, isInstance}]; |
| ASTContext &ctx = getASTContext(); |
| if (ctx.getCurrentGeneration() > stored.Generation) { |
| ctx.loadObjCMethods(this, selector, isInstance, stored.Generation, |
| stored.Methods); |
| stored.Generation = ctx.getCurrentGeneration(); |
| } |
| |
| return { stored.Methods.begin(), stored.Methods.end() }; |
| } |
| |
| void ClassDecl::recordObjCMethod(AbstractFunctionDecl *method) { |
| if (!ObjCMethodLookup) { |
| createObjCMethodLookup(); |
| } |
| |
| assert(method->isObjC() && "Not an Objective-C method"); |
| |
| // Record the method. |
| bool isInstanceMethod = method->isObjCInstanceMethod(); |
| auto selector = method->getObjCSelector(); |
| auto &vec = (*ObjCMethodLookup)[{selector, isInstanceMethod}].Methods; |
| |
| // In a non-empty vector, we could have duplicates or conflicts. |
| if (!vec.empty()) { |
| // Check whether we have a duplicate. This only checks more than one |
| // element in ill-formed code, so the linear search is acceptable. |
| if (std::find(vec.begin(), vec.end(), method) != vec.end()) |
| return; |
| |
| if (vec.size() == 1) { |
| // We have a conflict. |
| getASTContext().recordObjCMethodConflict(this, selector, |
| isInstanceMethod); |
| } |
| } else { |
| // Record the first method that has this selector. |
| getASTContext().recordObjCMethod(method); |
| } |
| |
| vec.push_back(method); |
| } |
| |
| static bool checkAccessibility(const DeclContext *useDC, |
| const DeclContext *sourceDC, |
| Accessibility access) { |
| if (!useDC) |
| return access >= Accessibility::Public; |
| |
| assert(sourceDC && "ValueDecl being accessed must have a valid DeclContext"); |
| switch (access) { |
| case Accessibility::Private: |
| return useDC == sourceDC || useDC->isChildContextOf(sourceDC); |
| case Accessibility::FilePrivate: |
| return useDC->getModuleScopeContext() == sourceDC->getModuleScopeContext(); |
| case Accessibility::Internal: { |
| const ModuleDecl *sourceModule = sourceDC->getParentModule(); |
| const DeclContext *useFile = useDC->getModuleScopeContext(); |
| if (useFile->getParentModule() == sourceModule) |
| return true; |
| if (auto *useSF = dyn_cast<SourceFile>(useFile)) |
| if (useSF->hasTestableImport(sourceModule)) |
| return true; |
| return false; |
| } |
| case Accessibility::Public: |
| case Accessibility::Open: |
| return true; |
| } |
| llvm_unreachable("bad Accessibility"); |
| } |
| |
| bool ValueDecl::isAccessibleFrom(const DeclContext *DC) const { |
| return checkAccessibility(DC, getDeclContext(), getFormalAccess()); |
| } |
| |
| bool AbstractStorageDecl::isSetterAccessibleFrom(const DeclContext *DC) const { |
| assert(isSettable(DC)); |
| |
| // If a stored property does not have a setter, it is still settable from the |
| // designated initializer constructor. In this case, don't check setter |
| // accessibility, it is not set. |
| if (hasStorage() && !isSettable(nullptr)) |
| return true; |
| |
| return checkAccessibility(DC, getDeclContext(), getSetterAccessibility()); |
| } |
| |
| bool DeclContext::lookupQualified(Type type, |
| DeclName member, |
| NLOptions options, |
| LazyResolver *typeResolver, |
| SmallVectorImpl<ValueDecl *> &decls) const { |
| using namespace namelookup; |
| assert(decls.empty() && "additive lookup not supported"); |
| |
| if (type->hasError()) |
| return false; |
| |
| auto checkLookupCascading = [this, options]() -> Optional<bool> { |
| switch (static_cast<unsigned>(options & NL_KnownDependencyMask)) { |
| case 0: |
| return isCascadingContextForLookup(/*functionsAreNonCascading=*/false); |
| case NL_KnownNonCascadingDependency: |
| return false; |
| case NL_KnownCascadingDependency: |
| return true; |
| case NL_KnownNoDependency: |
| return None; |
| default: |
| // FIXME: Use llvm::CountPopulation_64 when that's declared constexpr. |
| #if defined(__clang__) || defined(__GNUC__) |
| static_assert(__builtin_popcountll(NL_KnownDependencyMask) == 2, |
| "mask should only include four values"); |
| #endif |
| llvm_unreachable("mask only includes four values"); |
| } |
| }; |
| |
| // Look for module references. |
| if (auto moduleTy = type->getAs<ModuleType>()) { |
| ModuleDecl *module = moduleTy->getModule(); |
| auto topLevelScope = getModuleScopeContext(); |
| if (module == topLevelScope->getParentModule()) { |
| if (auto maybeLookupCascade = checkLookupCascading()) { |
| recordLookupOfTopLevelName(topLevelScope, member, |
| maybeLookupCascade.getValue()); |
| } |
| lookupInModule(module, /*accessPath=*/{}, member, decls, |
| NLKind::QualifiedLookup, ResolutionKind::Overloadable, |
| typeResolver, topLevelScope); |
| } else { |
| // Note: This is a lookup into another module. Unless we're compiling |
| // multiple modules at once, or if the other module re-exports this one, |
| // it shouldn't be possible to have a dependency from that module on |
| // anything in this one. |
| |
| // Perform the lookup in all imports of this module. |
| forAllVisibleModules(this, |
| [&](const ModuleDecl::ImportedModule &import) -> bool { |
| if (import.second != module) |
| return true; |
| lookupInModule(import.second, import.first, member, decls, |
| NLKind::QualifiedLookup, ResolutionKind::Overloadable, |
| typeResolver, topLevelScope); |
| // If we're able to do an unscoped lookup, we see everything. No need |
| // to keep going. |
| return !import.first.empty(); |
| }); |
| } |
| |
| llvm::SmallPtrSet<ValueDecl *, 4> knownDecls; |
| decls.erase(std::remove_if(decls.begin(), decls.end(), |
| [&](ValueDecl *vd) -> bool { |
| // If we're performing a type lookup, don't even attempt to validate |
| // the decl if its not a type. |
| if ((options & NL_OnlyTypes) && !isa<TypeDecl>(vd)) |
| return true; |
| |
| return !knownDecls.insert(vd).second; |
| }), decls.end()); |
| |
| if (auto *debugClient = topLevelScope->getParentModule()->getDebugClient()) |
| filterForDiscriminator(decls, debugClient); |
| |
| return !decls.empty(); |
| } |
| |
| auto &ctx = getASTContext(); |
| if (!ctx.LangOpts.EnableAccessControl) |
| options |= NL_IgnoreAccessibility; |
| |
| // The set of nominal type declarations we should (and have) visited. |
| SmallVector<NominalTypeDecl *, 4> stack; |
| llvm::SmallPtrSet<NominalTypeDecl *, 4> visited; |
| |
| // Handle nominal types. |
| bool wantProtocolMembers = false; |
| bool wantLookupInAllClasses = false; |
| if (auto nominal = type->getAnyNominal()) { |
| visited.insert(nominal); |
| stack.push_back(nominal); |
| |
| wantProtocolMembers = (options & NL_ProtocolMembers) && |
| !isa<ProtocolDecl>(nominal); |
| |
| // If we want dynamic lookup and we're searching in the |
| // AnyObject protocol, note this for later. |
| if (options & NL_DynamicLookup) { |
| if (auto proto = dyn_cast<ProtocolDecl>(nominal)) { |
| if (proto->isSpecificProtocol(KnownProtocolKind::AnyObject)) |
| wantLookupInAllClasses = true; |
| } |
| } |
| } |
| // Handle archetypes |
| else if (auto archetypeTy = type->getAs<ArchetypeType>()) { |
| // Look in the protocols to which the archetype conforms (always). |
| for (auto proto : archetypeTy->getConformsTo()) |
| if (visited.insert(proto).second) |
| stack.push_back(proto); |
| |
| // Look into the superclasses of this archetype. |
| if (auto superclassTy = archetypeTy->getSuperclass()) { |
| if (auto superclassDecl = superclassTy->getAnyNominal()) { |
| if (visited.insert(superclassDecl).second) { |
| stack.push_back(superclassDecl); |
| |
| wantProtocolMembers = (options & NL_ProtocolMembers) && |
| !isa<ProtocolDecl>(superclassDecl); |
| } |
| } |
| } |
| } |
| // Handle protocol compositions. |
| else if (auto compositionTy = type->getAs<ProtocolCompositionType>()) { |
| SmallVector<ProtocolDecl *, 4> protocols; |
| if (compositionTy->isExistentialType(protocols)) { |
| for (auto proto : protocols) { |
| if (visited.insert(proto).second) { |
| stack.push_back(proto); |
| |
| // If we want dynamic lookup and this is the AnyObject |
| // protocol, note this for later. |
| if ((options & NL_DynamicLookup) && |
| proto->isSpecificProtocol(KnownProtocolKind::AnyObject)) |
| wantLookupInAllClasses = true; |
| } |
| } |
| } |
| } else { |
| llvm_unreachable("Bad type for qualified lookup"); |
| } |
| |
| // Allow filtering of the visible declarations based on various |
| // criteria. |
| bool onlyCompleteObjectInits = false; |
| auto isAcceptableDecl = [&](NominalTypeDecl *current, ValueDecl *decl) -> bool { |
| // If the decl is currently being type checked, then we have something |
| // cyclic going on. Instead of poking at parts that are potentially not |
| // set up, just assume it is acceptable. This will make sure we produce an |
| // error later. |
| if (!decl->hasValidSignature()) |
| return true; |
| |
| // Filter out designated initializers, if requested. |
| if (onlyCompleteObjectInits) { |
| if (auto ctor = dyn_cast<ConstructorDecl>(decl)) { |
| if (!ctor->isInheritable()) |
| return false; |
| } else { |
| return false; |
| } |
| } |
| |
| // Ignore stub implementations. |
| if (auto ctor = dyn_cast<ConstructorDecl>(decl)) { |
| if (ctor->hasStubImplementation()) |
| return false; |
| } |
| |
| // Check access. |
| if (!(options & NL_IgnoreAccessibility)) |
| return decl->isAccessibleFrom(this); |
| |
| return true; |
| }; |
| |
| ReferencedNameTracker *tracker = nullptr; |
| if (auto containingSourceFile = dyn_cast<SourceFile>(getModuleScopeContext())) |
| tracker = containingSourceFile->getReferencedNameTracker(); |
| |
| bool isLookupCascading; |
| if (tracker) { |
| if (auto maybeLookupCascade = checkLookupCascading()) |
| isLookupCascading = maybeLookupCascade.getValue(); |
| else |
| tracker = nullptr; |
| } |
| |
| // Visit all of the nominal types we know about, discovering any others |
| // we need along the way. |
| while (!stack.empty()) { |
| auto current = stack.back(); |
| stack.pop_back(); |
| |
| if (tracker) |
| tracker->addUsedMember({current, member.getBaseName()},isLookupCascading); |
| |
| // Make sure we've resolved implicit constructors, if we need them. |
| if (member.getBaseName() == ctx.Id_init && typeResolver) |
| typeResolver->resolveImplicitConstructors(current); |
| |
| // Look for results within the current nominal type and its extensions. |
| bool currentIsProtocol = isa<ProtocolDecl>(current); |
| for (auto decl : current->lookupDirect(member)) { |
| // If we're performing a type lookup, don't even attempt to validate |
| // the decl if its not a type. |
| if ((options & NL_OnlyTypes) && !isa<TypeDecl>(decl)) |
| continue; |
| |
| // Resolve the declaration signature when we find the |
| // declaration. |
| if (typeResolver) |
| typeResolver->resolveDeclSignature(decl); |
| |
| if (isAcceptableDecl(current, decl)) |
| decls.push_back(decl); |
| } |
| |
| // Visit superclass. |
| if (auto classDecl = dyn_cast<ClassDecl>(current)) { |
| // If we're looking for initializers, only look at the superclass if the |
| // current class permits inheritance. Even then, only find complete |
| // object initializers. |
| bool visitSuperclass = true; |
| if (member.getBaseName() == ctx.Id_init) { |
| if (classDecl->inheritsSuperclassInitializers(typeResolver)) |
| onlyCompleteObjectInits = true; |
| else |
| visitSuperclass = false; |
| } |
| |
| if (visitSuperclass) { |
| if (auto superclassType = classDecl->getSuperclass()) |
| if (auto superclassDecl = superclassType->getClassOrBoundGenericClass()) |
| if (visited.insert(superclassDecl).second) |
| stack.push_back(superclassDecl); |
| } |
| } |
| |
| // If we're not looking at a protocol and we're not supposed to |
| // visit the protocols that this type conforms to, skip the next |
| // step. |
| if (!wantProtocolMembers && !currentIsProtocol) |
| continue; |
| |
| SmallVector<ProtocolDecl *, 4> protocols; |
| for (auto proto : current->getAllProtocols()) { |
| if (visited.insert(proto).second) { |
| stack.push_back(proto); |
| } |
| } |
| |
| // For a class, we don't need to visit the protocol members of the |
| // superclass: that's already handled. |
| if (isa<ClassDecl>(current)) |
| wantProtocolMembers = false; |
| } |
| |
| // If we want to perform lookup into all classes, do so now. |
| if (wantLookupInAllClasses) { |
| if (tracker) |
| tracker->addDynamicLookupName(member.getBaseName(), isLookupCascading); |
| |
| // Collect all of the visible declarations. |
| SmallVector<ValueDecl *, 4> allDecls; |
| forAllVisibleModules(this, [&](ModuleDecl::ImportedModule import) { |
| import.second->lookupClassMember(import.first, member, allDecls); |
| }); |
| |
| // For each declaration whose context is not something we've |
| // already visited above, add it to the list of declarations. |
| llvm::SmallPtrSet<ValueDecl *, 4> knownDecls; |
| for (auto decl : allDecls) { |
| // If we're performing a type lookup, don't even attempt to validate |
| // the decl if its not a type. |
| if ((options & NL_OnlyTypes) && !isa<TypeDecl>(decl)) |
| continue; |
| |
| if (typeResolver) |
| typeResolver->resolveDeclSignature(decl); |
| |
| // If the declaration has an override, name lookup will also have |
| // found the overridden method. Skip this declaration, because we |
| // prefer the overridden method. |
| if (decl->getOverriddenDecl()) |
| continue; |
| |
| auto dc = decl->getDeclContext(); |
| auto nominal = dyn_cast<NominalTypeDecl>(dc); |
| if (!nominal) { |
| auto ext = cast<ExtensionDecl>(dc); |
| nominal = ext->getExtendedType()->getAnyNominal(); |
| assert(nominal && "Couldn't find nominal type?"); |
| } |
| |
| // If we didn't visit this nominal type above, add this |
| // declaration to the list. |
| if (!visited.count(nominal) && knownDecls.insert(decl).second && |
| isAcceptableDecl(nominal, decl)) |
| decls.push_back(decl); |
| } |
| } |
| |
| // If we're supposed to remove overridden declarations, do so now. |
| if (options & NL_RemoveOverridden) |
| removeOverriddenDecls(decls); |
| |
| // If we're supposed to remove shadowed/hidden declarations, do so now. |
| ModuleDecl *M = getParentModule(); |
| if (options & NL_RemoveNonVisible) |
| removeShadowedDecls(decls, M, typeResolver); |
| |
| if (auto *debugClient = M->getDebugClient()) |
| filterForDiscriminator(decls, debugClient); |
| |
| // We're done. Report success/failure. |
| return !decls.empty(); |
| } |
| |
| void DeclContext::lookupAllObjCMethods( |
| ObjCSelector selector, |
| SmallVectorImpl<AbstractFunctionDecl *> &results) const { |
| // Collect all of the methods with this selector. |
| forAllVisibleModules(this, [&](ModuleDecl::ImportedModule import) { |
| import.second->lookupObjCMethods(selector, results); |
| }); |
| |
| // Filter out duplicates. |
| llvm::SmallPtrSet<AbstractFunctionDecl *, 8> visited; |
| results.erase( |
| std::remove_if(results.begin(), results.end(), |
| [&](AbstractFunctionDecl *func) -> bool { |
| return !visited.insert(func).second; |
| }), |
| results.end()); |
| } |