| //===--- TypeCheckGeneric.cpp - Generics ----------------------------------===// |
| // |
| // This source file is part of the Swift.org open source project |
| // |
| // Copyright (c) 2014 - 2016 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 support for generics. |
| // |
| //===----------------------------------------------------------------------===// |
| #include "TypeChecker.h" |
| #include "GenericTypeResolver.h" |
| #include "swift/AST/ArchetypeBuilder.h" |
| #include "swift/AST/GenericEnvironment.h" |
| #include "swift/AST/Types.h" |
| #include "swift/Basic/Defer.h" |
| |
| using namespace swift; |
| |
| Type DependentGenericTypeResolver::resolveGenericTypeParamType( |
| GenericTypeParamType *gp) { |
| auto gpDecl = gp->getDecl(); |
| assert(gpDecl && "Missing generic parameter declaration"); |
| |
| // Hack: See parseGenericParameters(). When the issue there is fixed, |
| // we won't need the isInvalid() check anymore. |
| if (gpDecl->isInvalid()) |
| return ErrorType::get(gpDecl->getASTContext()); |
| |
| // Don't resolve generic parameters. |
| return gp; |
| } |
| |
| Type DependentGenericTypeResolver::resolveDependentMemberType( |
| Type baseTy, |
| DeclContext *DC, |
| SourceRange baseRange, |
| ComponentIdentTypeRepr *ref) { |
| auto archetype = Builder.resolveArchetype(baseTy); |
| assert(archetype && "Bad generic context nesting?"); |
| |
| return archetype->getRepresentative() |
| ->getNestedType(ref->getIdentifier(), Builder) |
| ->getDependentType(/*FIXME: */{ }, /*allowUnresolved=*/true); |
| } |
| |
| Type DependentGenericTypeResolver::resolveSelfAssociatedType( |
| Type selfTy, AssociatedTypeDecl *assocType) { |
| auto archetype = Builder.resolveArchetype(selfTy); |
| assert(archetype && "Bad generic context nesting?"); |
| |
| return archetype->getRepresentative() |
| ->getNestedType(assocType->getName(), Builder) |
| ->getDependentType(/*FIXME: */{ }, /*allowUnresolved=*/true); |
| } |
| |
| Type DependentGenericTypeResolver::resolveTypeOfContext(DeclContext *dc) { |
| return dc->getSelfInterfaceType(); |
| } |
| |
| Type DependentGenericTypeResolver::resolveTypeOfDecl(TypeDecl *decl) { |
| return decl->getDeclaredInterfaceType(); |
| } |
| |
| void DependentGenericTypeResolver::recordParamType(ParamDecl *decl, Type type) { |
| // Do nothing |
| } |
| |
| Type GenericTypeToArchetypeResolver::resolveGenericTypeParamType( |
| GenericTypeParamType *gp) { |
| auto gpDecl = gp->getDecl(); |
| assert(gpDecl && "Missing generic parameter declaration"); |
| |
| // Hack: See parseGenericParameters(). When the issue there is fixed, |
| // we won't need the isInvalid() check anymore. |
| if (gpDecl->isInvalid() || !GenericEnv) |
| return ErrorType::get(gpDecl->getASTContext()); |
| |
| auto type = GenericEnv->getMappingIfPresent(gp); |
| if (!type) |
| return ErrorType::get(gpDecl->getASTContext());; |
| |
| return *type; |
| } |
| |
| Type GenericTypeToArchetypeResolver::resolveDependentMemberType( |
| Type baseTy, |
| DeclContext *DC, |
| SourceRange baseRange, |
| ComponentIdentTypeRepr *ref) { |
| llvm_unreachable("Dependent type after archetype substitution"); |
| } |
| |
| Type GenericTypeToArchetypeResolver::resolveSelfAssociatedType( |
| Type selfTy, AssociatedTypeDecl *assocType) { |
| llvm_unreachable("Dependent type after archetype substitution"); |
| } |
| |
| Type GenericTypeToArchetypeResolver::resolveTypeOfContext(DeclContext *dc) { |
| // FIXME: Fallback case. |
| if (!isa<ExtensionDecl>(dc) && |
| dc->isGenericContext() && |
| !dc->isValidGenericContext()) |
| return dc->getSelfInterfaceType(); |
| |
| return ArchetypeBuilder::mapTypeIntoContext( |
| dc->getParentModule(), GenericEnv, |
| dc->getSelfInterfaceType()); |
| } |
| |
| Type GenericTypeToArchetypeResolver::resolveTypeOfDecl(TypeDecl *decl) { |
| // Hack for 'out of context' GenericTypeParamDecls when resolving |
| // a generic typealias |
| if (auto *paramDecl = dyn_cast<GenericTypeParamDecl>(decl)) { |
| return decl->getDeclContext()->getGenericEnvironmentOfContext() |
| ->mapTypeIntoContext(paramDecl->getDeclaredInterfaceType() |
| ->castTo<GenericTypeParamType>()); |
| } |
| |
| auto *aliasDecl = cast<TypeAliasDecl>(decl); |
| if (aliasDecl->isInvalid()) |
| return ErrorType::get(aliasDecl->getASTContext()); |
| return aliasDecl->getAliasType(); |
| } |
| |
| void GenericTypeToArchetypeResolver::recordParamType(ParamDecl *decl, Type type) { |
| decl->setType(type); |
| |
| // When type checking a closure or subscript index, this is the only |
| // resolver that runs, so make sure we also set the interface type, |
| // if one was not already set. |
| // |
| // When type checking functions, the CompleteGenericTypeResolver sets |
| // the interface type. |
| if (!decl->hasInterfaceType()) |
| decl->setInterfaceType(ArchetypeBuilder::mapTypeOutOfContext( |
| decl->getDeclContext()->getParentModule(), |
| GenericEnv, |
| type)); |
| } |
| |
| Type CompleteGenericTypeResolver::resolveGenericTypeParamType( |
| GenericTypeParamType *gp) { |
| auto gpDecl = gp->getDecl(); |
| assert(gpDecl && "Missing generic parameter declaration"); |
| |
| // Hack: See parseGenericParameters(). When the issue there is fixed, |
| // we won't need the isInvalid() check anymore. |
| if (gpDecl->isInvalid()) |
| return ErrorType::get(gpDecl->getASTContext()); |
| |
| // Retrieve the potential archetype corresponding to this generic type |
| // parameter. |
| // FIXME: When generic parameters can map down to specific types, do so |
| // here. |
| auto pa = Builder.resolveArchetype(gp); |
| (void)pa; |
| |
| return gp; |
| } |
| |
| |
| Type CompleteGenericTypeResolver::resolveDependentMemberType( |
| Type baseTy, |
| DeclContext *DC, |
| SourceRange baseRange, |
| ComponentIdentTypeRepr *ref) { |
| // Resolve the base to a potential archetype. |
| auto basePA = Builder.resolveArchetype(baseTy); |
| assert(basePA && "Missing potential archetype for base"); |
| basePA = basePA->getRepresentative(); |
| |
| // Retrieve the potential archetype for the nested type. |
| auto nestedPA = basePA->getNestedType(ref->getIdentifier(), Builder); |
| |
| // If this potential archetype was renamed due to typo correction, |
| // complain and fix it. |
| if (nestedPA->wasRenamed()) { |
| auto newName = nestedPA->getName(); |
| TC.diagnose(ref->getIdLoc(), diag::invalid_member_type_suggest, |
| baseTy, ref->getIdentifier(), newName) |
| .fixItReplace(ref->getIdLoc(), newName.str()); |
| ref->overwriteIdentifier(newName); |
| nestedPA->setAlreadyDiagnosedRename(); |
| |
| // Go get the actual nested type. |
| nestedPA = basePA->getNestedType(newName, Builder); |
| assert(!nestedPA->wasRenamed()); |
| } |
| |
| // If the nested type has been resolved to an associated type, use it. |
| if (auto assocType = nestedPA->getResolvedAssociatedType()) { |
| ref->setValue(assocType); |
| return DependentMemberType::get(baseTy, assocType); |
| } |
| |
| // If the nested type comes from a type alias, use either the alias's |
| // concrete type, or resolve its components down to another dependent member. |
| if (auto alias = nestedPA->getTypeAliasDecl()) { |
| ref->setValue(alias); |
| return TC.substMemberTypeWithBase(DC->getParentModule(), alias, baseTy); |
| } |
| |
| Identifier name = ref->getIdentifier(); |
| SourceLoc nameLoc = ref->getIdLoc(); |
| |
| // Check whether the name can be found in the superclass. |
| // FIXME: The archetype builder should be doing this and mapping down to a |
| // concrete type. |
| if (auto superclassTy = basePA->getSuperclass()) { |
| if (auto lookup = TC.lookupMemberType(DC, superclassTy, name)) { |
| if (lookup.isAmbiguous()) { |
| TC.diagnoseAmbiguousMemberType(baseTy, baseRange, name, nameLoc, |
| lookup); |
| return ErrorType::get(TC.Context); |
| } |
| |
| ref->setValue(lookup.front().first); |
| // FIXME: Record (via type sugar) that this was referenced via baseTy. |
| return lookup.front().second; |
| } |
| } |
| |
| // Complain that there is no suitable type. |
| TC.diagnose(nameLoc, diag::invalid_member_type, name, baseTy) |
| .highlight(baseRange); |
| return ErrorType::get(TC.Context); |
| } |
| |
| Type CompleteGenericTypeResolver::resolveSelfAssociatedType( |
| Type selfTy, AssociatedTypeDecl *assocType) { |
| return Builder.resolveArchetype(selfTy)->getRepresentative() |
| ->getNestedType(assocType->getName(), Builder) |
| ->getDependentType(/*FIXME: */{ }, /*allowUnresolved=*/false); |
| } |
| |
| Type CompleteGenericTypeResolver::resolveTypeOfContext(DeclContext *dc) { |
| return dc->getSelfInterfaceType(); |
| } |
| |
| Type CompleteGenericTypeResolver::resolveTypeOfDecl(TypeDecl *decl) { |
| return decl->getDeclaredInterfaceType(); |
| } |
| |
| void |
| CompleteGenericTypeResolver::recordParamType(ParamDecl *decl, Type type) { |
| decl->setInterfaceType(type); |
| } |
| |
| /// Check the generic parameters in the given generic parameter list (and its |
| /// parent generic parameter lists) according to the given resolver. |
| void TypeChecker::checkGenericParamList(ArchetypeBuilder *builder, |
| GenericParamList *genericParams, |
| GenericSignature *parentSig, |
| GenericTypeResolver *resolver) { |
| // If there is a parent context, add the generic parameters and requirements |
| // from that context. |
| if (builder) |
| builder->addGenericSignature(parentSig); |
| |
| // If there aren't any generic parameters at this level, we're done. |
| if (!genericParams) |
| return; |
| |
| assert(genericParams->size() > 0 && "Parsed an empty generic parameter list?"); |
| |
| // Determine where and how to perform name lookup for the generic |
| // parameter lists and where clause. |
| TypeResolutionOptions options; |
| DeclContext *lookupDC = genericParams->begin()[0]->getDeclContext(); |
| if (!lookupDC->isModuleScopeContext()) { |
| assert(isa<GenericTypeDecl>(lookupDC) || isa<ExtensionDecl>(lookupDC) || |
| isa<AbstractFunctionDecl>(lookupDC) && |
| "not a proper generic parameter context?"); |
| options = TR_GenericSignature; |
| } |
| |
| // First, add the generic parameters to the archetype builder. |
| // Do this before checking the inheritance clause, since it may |
| // itself be dependent on one of these parameters. |
| if (builder) { |
| for (auto param : *genericParams) |
| builder->addGenericParameter(param); |
| } |
| |
| // Now, check the inheritance clauses of each parameter. |
| for (auto param : *genericParams) { |
| checkInheritanceClause(param, resolver); |
| |
| if (builder) { |
| builder->addGenericParameterRequirements(param); |
| |
| // Infer requirements from the inherited types. |
| for (const auto &inherited : param->getInherited()) { |
| builder->inferRequirements(inherited, genericParams); |
| } |
| } |
| } |
| |
| // Visit each of the requirements, adding them to the builder. |
| // Add the requirements clause to the builder, validating the types in |
| // the requirements clause along the way. |
| for (auto &req : genericParams->getRequirements()) { |
| if (req.isInvalid()) |
| continue; |
| |
| switch (req.getKind()) { |
| case RequirementReprKind::TypeConstraint: { |
| // Validate the types. |
| if (validateType(req.getSubjectLoc(), lookupDC, options, resolver)) { |
| req.setInvalid(); |
| continue; |
| } |
| |
| if (validateType(req.getConstraintLoc(), lookupDC, options, |
| resolver)) { |
| req.setInvalid(); |
| continue; |
| } |
| |
| // FIXME: Feels too early to perform this check. |
| if (!req.getConstraint()->isExistentialType() && |
| !req.getConstraint()->getClassOrBoundGenericClass()) { |
| diagnose(genericParams->getWhereLoc(), |
| diag::requires_conformance_nonprotocol, |
| req.getSubjectLoc(), req.getConstraintLoc()); |
| req.getConstraintLoc().setInvalidType(Context); |
| req.setInvalid(); |
| continue; |
| } |
| |
| break; |
| } |
| |
| case RequirementReprKind::SameType: |
| if (validateType(req.getFirstTypeLoc(), lookupDC, options, |
| resolver)) { |
| req.setInvalid(); |
| continue; |
| } |
| |
| if (validateType(req.getSecondTypeLoc(), lookupDC, options, |
| resolver)) { |
| req.setInvalid(); |
| continue; |
| } |
| |
| break; |
| } |
| |
| if (builder && builder->addRequirement(req)) |
| req.setInvalid(); |
| } |
| } |
| |
| /// Check the signature of a generic function. |
| static bool checkGenericFuncSignature(TypeChecker &tc, |
| ArchetypeBuilder *builder, |
| AbstractFunctionDecl *func, |
| GenericTypeResolver &resolver) { |
| bool badType = false; |
| func->setIsBeingTypeChecked(); |
| |
| // Check the generic parameter list. |
| auto genericParams = func->getGenericParams(); |
| |
| tc.checkGenericParamList( |
| builder, genericParams, |
| func->getDeclContext()->getGenericSignatureOfContext(), |
| &resolver); |
| |
| // Check the parameter patterns. |
| for (auto params : func->getParameterLists()) { |
| // Check the pattern. |
| if (tc.typeCheckParameterList(params, func, TypeResolutionOptions(), |
| resolver)) |
| badType = true; |
| |
| // Infer requirements from the pattern. |
| if (builder) { |
| builder->inferRequirements(params, genericParams); |
| } |
| } |
| |
| // If there is a declared result type, check that as well. |
| if (auto fn = dyn_cast<FuncDecl>(func)) { |
| if (!fn->getBodyResultTypeLoc().isNull()) { |
| // Check the result type of the function. |
| TypeResolutionOptions options; |
| if (fn->hasDynamicSelf()) |
| options |= TR_DynamicSelfResult; |
| |
| if (tc.validateType(fn->getBodyResultTypeLoc(), fn, options, &resolver)) { |
| badType = true; |
| } |
| |
| // Infer requirements from it. |
| if (builder && fn->getBodyResultTypeLoc().getTypeRepr()) { |
| builder->inferRequirements(fn->getBodyResultTypeLoc(), genericParams); |
| } |
| } |
| } |
| |
| func->setIsBeingTypeChecked(false); |
| return badType; |
| } |
| |
| /// Determine whether the given type is \c Self, an associated type of \c Self, |
| /// or a concrete type. |
| static bool isSelfDerivedOrConcrete(Type protoSelf, Type type) { |
| // Check for a concrete type. |
| if (!type->hasTypeParameter()) |
| return true; |
| |
| // Unwrap dependent member types. |
| while (auto depMem = type->getAs<DependentMemberType>()) { |
| type = depMem->getBase(); |
| } |
| |
| if (type->is<GenericTypeParamType>()) |
| return type->isEqual(protoSelf); |
| |
| return false; |
| } |
| |
| void |
| TypeChecker::prepareGenericParamList(GenericParamList *gp, |
| DeclContext *dc) { |
| Accessibility access; |
| if (auto *fd = dyn_cast<FuncDecl>(dc)) |
| access = fd->getFormalAccess(); |
| else if (auto *nominal = dyn_cast<NominalTypeDecl>(dc)) |
| access = nominal->getFormalAccess(); |
| else |
| access = Accessibility::Internal; |
| access = std::max(access, Accessibility::Internal); |
| |
| unsigned depth = gp->getDepth(); |
| for (auto paramDecl : *gp) { |
| paramDecl->setDepth(depth); |
| if (!paramDecl->hasAccessibility()) |
| paramDecl->setAccessibility(access); |
| } |
| } |
| |
| GenericSignature * |
| TypeChecker::validateGenericFuncSignature(AbstractFunctionDecl *func) { |
| bool invalid = false; |
| |
| auto *gp = func->getGenericParams(); |
| if (gp) |
| prepareGenericParamList(gp, func); |
| |
| // Create the archetype builder. |
| ArchetypeBuilder builder = createArchetypeBuilder(func->getParentModule()); |
| |
| // Type check the function declaration, treating all generic type |
| // parameters as dependent, unresolved. |
| DependentGenericTypeResolver dependentResolver(builder); |
| if (checkGenericFuncSignature(*this, &builder, func, dependentResolver)) |
| invalid = true; |
| |
| // If this triggered a recursive validation, back out: we're done. |
| // FIXME: This is an awful hack. |
| if (func->hasInterfaceType()) |
| return nullptr; |
| |
| // Finalize the generic requirements. |
| (void)builder.finalize(func->getLoc()); |
| |
| // The archetype builder now has all of the requirements, although there might |
| // still be errors that have not yet been diagnosed. Revert the generic |
| // function signature and type-check it again, completely. |
| revertGenericFuncSignature(func); |
| if (gp) |
| revertGenericParamList(gp); |
| |
| CompleteGenericTypeResolver completeResolver(*this, builder); |
| if (checkGenericFuncSignature(*this, nullptr, func, completeResolver)) |
| invalid = true; |
| if (builder.diagnoseRemainingRenames(func->getLoc())) |
| invalid = true; |
| |
| // The generic function signature is complete and well-formed. Determine |
| // the type of the generic function. |
| auto sig = builder.getGenericSignature(); |
| |
| // For a generic requirement in a protocol, make sure that the requirement |
| // set didn't add any requirements to Self or its associated types. |
| if (!invalid && func->getGenericParams() && |
| isa<ProtocolDecl>(func->getDeclContext())) { |
| auto proto = cast<ProtocolDecl>(func->getDeclContext()); |
| auto protoSelf = proto->getSelfInterfaceType(); |
| for (auto req : sig->getRequirements()) { |
| // If one of the types in the requirement is dependent on a non-Self |
| // type parameter, this requirement is okay. |
| if (!isSelfDerivedOrConcrete(protoSelf, req.getFirstType()) || |
| !isSelfDerivedOrConcrete(protoSelf, req.getSecondType())) |
| continue; |
| |
| // The conformance of 'Self' to the protocol is okay. |
| if (req.getKind() == RequirementKind::Conformance && |
| req.getSecondType()->getAs<ProtocolType>()->getDecl() == proto && |
| req.getFirstType()->is<GenericTypeParamType>()) |
| continue; |
| |
| diagnose(func, |
| Context.LangOpts.EffectiveLanguageVersion[0] >= 4 |
| ? diag::requirement_restricts_self |
| : diag::requirement_restricts_self_swift3, |
| func->getDescriptiveKind(), func->getFullName(), |
| req.getFirstType().getString(), |
| static_cast<unsigned>(req.getKind()), |
| req.getSecondType().getString()); |
| |
| if (Context.LangOpts.EffectiveLanguageVersion[0] >= 4) |
| invalid = true; |
| } |
| } |
| |
| // Debugging of the archetype builder and generic signature generation. |
| if (Context.LangOpts.DebugGenericSignatures) { |
| func->dumpRef(llvm::errs()); |
| llvm::errs() << "\n"; |
| builder.dump(llvm::errs()); |
| llvm::errs() << "Generic signature: "; |
| sig->print(llvm::errs()); |
| llvm::errs() << "\n"; |
| llvm::errs() << "Canonical generic signature: "; |
| sig->getCanonicalSignature()->print(llvm::errs()); |
| llvm::errs() << "\n"; |
| } |
| |
| if (invalid) { |
| func->setInterfaceType(ErrorType::get(Context)); |
| func->setInvalid(); |
| // null doesn't mean error here: callers still expect the signature. |
| return sig; |
| } |
| |
| configureInterfaceType(func, sig); |
| return sig; |
| } |
| |
| void TypeChecker::configureInterfaceType(AbstractFunctionDecl *func, |
| GenericSignature *sig) { |
| Type funcTy; |
| Type initFuncTy; |
| |
| if (auto fn = dyn_cast<FuncDecl>(func)) { |
| funcTy = fn->getBodyResultTypeLoc().getType(); |
| if (!funcTy) |
| funcTy = TupleType::getEmpty(Context); |
| |
| } else if (auto ctor = dyn_cast<ConstructorDecl>(func)) { |
| auto *dc = ctor->getDeclContext(); |
| |
| funcTy = dc->getSelfInterfaceType(); |
| if (!funcTy) |
| funcTy = ErrorType::get(Context); |
| |
| // Adjust result type for failability. |
| if (ctor->getFailability() != OTK_None) |
| funcTy = OptionalType::get(ctor->getFailability(), funcTy); |
| |
| initFuncTy = funcTy; |
| } else { |
| assert(isa<DestructorDecl>(func)); |
| funcTy = TupleType::getEmpty(Context); |
| } |
| |
| auto paramLists = func->getParameterLists(); |
| SmallVector<ParameterList*, 4> storedParamLists; |
| |
| // FIXME: Destructors don't have the '()' pattern in their signature, so |
| // paste it here. |
| if (isa<DestructorDecl>(func)) { |
| assert(paramLists.size() == 1 && "Only the self paramlist"); |
| storedParamLists.push_back(paramLists[0]); |
| storedParamLists.push_back(ParameterList::createEmpty(Context)); |
| paramLists = storedParamLists; |
| } |
| |
| bool hasSelf = func->getDeclContext()->isTypeContext(); |
| for (unsigned i = 0, e = paramLists.size(); i != e; ++i) { |
| Type argTy; |
| Type initArgTy; |
| |
| Type selfTy; |
| if (i == e-1 && hasSelf) { |
| selfTy = func->computeInterfaceSelfType(); |
| // Substitute in our own 'self' parameter. |
| |
| argTy = selfTy; |
| if (initFuncTy) { |
| initArgTy = func->computeInterfaceSelfType(/*isInitializingCtor=*/true); |
| } |
| } else { |
| argTy = paramLists[e - i - 1]->getInterfaceType(Context); |
| |
| if (initFuncTy) |
| initArgTy = argTy; |
| } |
| |
| // 'throws' only applies to the innermost function. |
| AnyFunctionType::ExtInfo info; |
| if (i == 0 && func->hasThrows()) |
| info = info.withThrows(); |
| |
| assert(!argTy->hasArchetype()); |
| assert(!funcTy->hasArchetype()); |
| if (initFuncTy) |
| assert(!initFuncTy->hasArchetype()); |
| |
| if (sig && i == e-1) { |
| funcTy = GenericFunctionType::get(sig, argTy, funcTy, info); |
| if (initFuncTy) |
| initFuncTy = GenericFunctionType::get(sig, initArgTy, initFuncTy, info); |
| } else { |
| funcTy = FunctionType::get(argTy, funcTy, info); |
| if (initFuncTy) |
| initFuncTy = FunctionType::get(initArgTy, initFuncTy, info); |
| } |
| } |
| |
| // Record the interface type. |
| func->setInterfaceType(funcTy); |
| if (initFuncTy) |
| cast<ConstructorDecl>(func)->setInitializerInterfaceType(initFuncTy); |
| |
| if (func->getGenericParams()) { |
| // Collect all generic params referenced in parameter types, |
| // return type or requirements. |
| SmallPtrSet<GenericTypeParamDecl *, 4> referencedGenericParams; |
| |
| auto visitorFn = [&referencedGenericParams](Type t) { |
| if (auto *paramTy = t->getAs<GenericTypeParamType>()) |
| referencedGenericParams.insert(paramTy->getDecl()); |
| }; |
| |
| funcTy->castTo<AnyFunctionType>()->getInput().visit(visitorFn); |
| funcTy->castTo<AnyFunctionType>()->getResult().visit(visitorFn); |
| |
| auto requirements = sig->getRequirements(); |
| for (auto req : requirements) { |
| if (req.getKind() == RequirementKind::SameType) { |
| // Same type requirements may allow for generic |
| // inference, even if this generic parameter |
| // is not mentioned in the function signature. |
| // TODO: Make the test more precise. |
| auto left = req.getFirstType(); |
| auto right = req.getSecondType(); |
| // For now consider any references inside requirements |
| // as a possibility to infer the generic type. |
| left.visit(visitorFn); |
| right.visit(visitorFn); |
| } |
| } |
| |
| // Find the depth of the function's own generic parameters. |
| unsigned fnGenericParamsDepth = func->getGenericParams()->getDepth(); |
| |
| // Check that every generic parameter type from the signature is |
| // among referencedArchetypes. |
| for (auto *genParam : sig->getGenericParams()) { |
| auto *paramDecl = genParam->getDecl(); |
| if (paramDecl->getDepth() != fnGenericParamsDepth) |
| continue; |
| if (!referencedGenericParams.count(paramDecl)) { |
| // Produce an error that this generic parameter cannot be bound. |
| diagnose(paramDecl->getLoc(), diag::unreferenced_generic_parameter, |
| paramDecl->getNameStr()); |
| func->setInvalid(); |
| } |
| } |
| } |
| } |
| |
| /// Visit the given generic parameter lists from the outermost to the innermost, |
| /// calling the visitor function for each list. |
| static void visitOuterToInner( |
| GenericParamList *genericParams, |
| llvm::function_ref<void(GenericParamList *)> visitor) { |
| if (auto outerGenericParams = genericParams->getOuterParameters()) |
| visitOuterToInner(outerGenericParams, visitor); |
| |
| visitor(genericParams); |
| } |
| |
| GenericEnvironment *TypeChecker::checkGenericEnvironment( |
| GenericParamList *genericParams, |
| DeclContext *dc, |
| GenericSignature *parentSig, |
| bool allowConcreteGenericParams, |
| llvm::function_ref<void(ArchetypeBuilder &)> |
| inferRequirements) { |
| assert(genericParams && "Missing generic parameters?"); |
| bool recursivelyVisitGenericParams = |
| genericParams->getOuterParameters() && !parentSig; |
| |
| // Create the archetype builder. |
| Module *module = dc->getParentModule(); |
| ArchetypeBuilder builder = createArchetypeBuilder(module); |
| |
| // Type check the generic parameters, treating all generic type |
| // parameters as dependent, unresolved. |
| DependentGenericTypeResolver dependentResolver(builder); |
| if (recursivelyVisitGenericParams) { |
| visitOuterToInner(genericParams, |
| [&](GenericParamList *gpList) { |
| checkGenericParamList(&builder, gpList, nullptr, &dependentResolver); |
| }); |
| } else { |
| checkGenericParamList(&builder, genericParams, parentSig, |
| &dependentResolver); |
| } |
| |
| /// Perform any necessary requirement inference. |
| inferRequirements(builder); |
| |
| // Finalize the generic requirements. |
| (void)builder.finalize(genericParams->getSourceRange().Start, |
| allowConcreteGenericParams); |
| |
| // The archetype builder now has all of the requirements, although there might |
| // still be errors that have not yet been diagnosed. Revert the signature |
| // and type-check it again, completely. |
| if (recursivelyVisitGenericParams) { |
| visitOuterToInner(genericParams, |
| [&](GenericParamList *gpList) { |
| revertGenericParamList(gpList); |
| }); |
| } else { |
| revertGenericParamList(genericParams); |
| } |
| CompleteGenericTypeResolver completeResolver(*this, builder); |
| if (recursivelyVisitGenericParams) { |
| visitOuterToInner(genericParams, |
| [&](GenericParamList *gpList) { |
| checkGenericParamList(nullptr, gpList, nullptr, &completeResolver); |
| }); |
| } else { |
| checkGenericParamList(nullptr, genericParams, parentSig, |
| &completeResolver); |
| } |
| |
| /// Perform any necessary requirement inference. |
| inferRequirements(builder); |
| |
| // Finalize the generic requirements. |
| (void)builder.finalize(genericParams->getSourceRange().Start, |
| allowConcreteGenericParams); |
| (void)builder.diagnoseRemainingRenames(genericParams->getSourceRange().Start); |
| |
| // Record the generic type parameter types and the requirements. |
| auto sig = builder.getGenericSignature(); |
| |
| // Debugging of the archetype builder and generic signature generation. |
| if (Context.LangOpts.DebugGenericSignatures) { |
| dc->printContext(llvm::errs()); |
| llvm::errs() << "\n"; |
| builder.dump(llvm::errs()); |
| llvm::errs() << "Generic signature: "; |
| sig->print(llvm::errs()); |
| llvm::errs() << "\n"; |
| llvm::errs() << "Canonical generic signature: "; |
| sig->getCanonicalSignature()->print(llvm::errs()); |
| llvm::errs() << "\n"; |
| } |
| |
| // Form the generic environment. |
| return builder.getGenericEnvironment(sig); |
| } |
| |
| static void revertDependentTypeLoc(TypeLoc &tl) { |
| // If there's no type representation, there's nothing to revert. |
| if (!tl.getTypeRepr()) |
| return; |
| |
| // Don't revert an error type; we've already complained. |
| if (tl.wasValidated() && tl.isError()) |
| return; |
| |
| // Make sure we validate the type again. |
| tl.setType(Type(), /*validated=*/false); |
| } |
| |
| /// Revert the dependent types within the given generic parameter list. |
| void TypeChecker::revertGenericParamList(GenericParamList *genericParams) { |
| // Revert the inherited clause of the generic parameter list. |
| for (auto param : *genericParams) { |
| param->setCheckedInheritanceClause(false); |
| for (auto &inherited : param->getInherited()) |
| revertDependentTypeLoc(inherited); |
| } |
| |
| // Revert the requirements of the generic parameter list. |
| for (auto &req : genericParams->getRequirements()) { |
| if (req.isInvalid()) |
| continue; |
| |
| switch (req.getKind()) { |
| case RequirementReprKind::TypeConstraint: { |
| revertDependentTypeLoc(req.getSubjectLoc()); |
| revertDependentTypeLoc(req.getConstraintLoc()); |
| break; |
| } |
| |
| case RequirementReprKind::SameType: |
| revertDependentTypeLoc(req.getFirstTypeLoc()); |
| revertDependentTypeLoc(req.getSecondTypeLoc()); |
| break; |
| } |
| } |
| } |
| |
| void TypeChecker::validateGenericTypeSignature(GenericTypeDecl *typeDecl) { |
| if (typeDecl->isValidatingGenericSignature()) |
| return; |
| |
| typeDecl->setIsValidatingGenericSignature(); |
| |
| SWIFT_DEFER { typeDecl->setIsValidatingGenericSignature(false); }; |
| |
| auto *gp = typeDecl->getGenericParams(); |
| auto *dc = typeDecl->getDeclContext(); |
| |
| if (!gp) { |
| auto *parentEnv = dc->getGenericEnvironmentOfContext(); |
| typeDecl->setGenericEnvironment(parentEnv); |
| return; |
| } |
| |
| gp->setOuterParameters(dc->getGenericParamsOfContext()); |
| |
| prepareGenericParamList(gp, typeDecl); |
| |
| auto *env = checkGenericEnvironment(gp, dc, dc->getGenericSignatureOfContext(), |
| /*allowConcreteGenericParams=*/false); |
| typeDecl->setGenericEnvironment(env); |
| } |
| |
| void TypeChecker::revertGenericFuncSignature(AbstractFunctionDecl *func) { |
| // Revert the result type. |
| if (auto fn = dyn_cast<FuncDecl>(func)) |
| if (!fn->getBodyResultTypeLoc().isNull()) |
| revertDependentTypeLoc(fn->getBodyResultTypeLoc()); |
| |
| // Revert the body parameter types. |
| for (auto paramList : func->getParameterLists()) { |
| for (auto ¶m : *paramList) { |
| revertDependentTypeLoc(param->getTypeLoc()); |
| } |
| } |
| } |
| |
| /// Create a text string that describes the bindings of generic parameters that |
| /// are relevant to the given set of types, e.g., "[with T = Bar, U = Wibble]". |
| /// |
| /// \param types The types that will be scanned for generic type parameters, |
| /// which will be used in the resulting type. |
| /// |
| /// \param genericSig The actual generic parameters, whose names will be used |
| /// in the resulting text. |
| /// |
| /// \param substitutions The generic parameter -> generic argument substitutions |
| /// that will have been applied to these types. These are used to produce the |
| /// "parameter = argument" bindings in the test. |
| static std::string gatherGenericParamBindingsText( |
| ArrayRef<Type> types, |
| GenericSignature *genericSig, |
| const TypeSubstitutionMap &substitutions) { |
| llvm::SmallPtrSet<GenericTypeParamType *, 2> knownGenericParams; |
| for (auto type : types) { |
| type.visit([&](Type type) { |
| if (auto gp = type->getAs<GenericTypeParamType>()) { |
| knownGenericParams.insert(gp->getCanonicalType() |
| ->castTo<GenericTypeParamType>()); |
| } |
| }); |
| } |
| |
| if (knownGenericParams.empty()) |
| return ""; |
| |
| SmallString<128> result; |
| for (auto gp : genericSig->getGenericParams()) { |
| auto canonGP = gp->getCanonicalType()->castTo<GenericTypeParamType>(); |
| if (!knownGenericParams.count(canonGP)) |
| continue; |
| |
| if (result.empty()) |
| result += " [with "; |
| else |
| result += ", "; |
| result += gp->getName().str(); |
| result += " = "; |
| |
| auto found = substitutions.find(canonGP); |
| if (found == substitutions.end()) |
| return ""; |
| |
| result += found->second.getString(); |
| } |
| |
| result += "]"; |
| return result.str().str(); |
| } |
| |
| TypeChecker::CheckGenericArgsResult |
| TypeChecker::checkGenericArguments(DeclContext *dc, SourceLoc loc, |
| SourceLoc noteLoc, |
| Type owner, |
| GenericSignature *genericSig, |
| const TypeSubstitutionMap &substitutions, |
| UnsatisfiedDependency *unsatisfiedDependency) { |
| // Check each of the requirements. |
| Module *module = dc->getParentModule(); |
| for (const auto &req : genericSig->getRequirements()) { |
| Type firstType = req.getFirstType().subst(module, substitutions); |
| if (firstType.isNull()) { |
| // Another requirement will fail later; just continue. |
| continue; |
| } |
| |
| Type secondType = req.getSecondType(); |
| if (secondType) { |
| secondType = secondType.subst(module, substitutions); |
| if (secondType.isNull()) { |
| // Another requirement will fail later; just continue. |
| continue; |
| } |
| } |
| |
| switch (req.getKind()) { |
| case RequirementKind::Conformance: { |
| if (auto *classDecl = firstType->getClassOrBoundGenericClass()) { |
| // If we have a callback to report dependencies, do so. |
| // FIXME: Woefully inadequate. |
| if (unsatisfiedDependency && |
| (*unsatisfiedDependency)(requestTypeCheckSuperclass(classDecl))) |
| return CheckGenericArgsResult::Unsatisfied; |
| } |
| |
| // Protocol conformance requirements. |
| auto proto = secondType->castTo<ProtocolType>(); |
| // FIXME: This should track whether this should result in a private |
| // or non-private dependency. |
| // FIXME: Do we really need "used" at this point? |
| // FIXME: Poor location information. How much better can we do here? |
| if (!conformsToProtocol(firstType, proto->getDecl(), dc, |
| ConformanceCheckFlags::Used, loc)) { |
| return CheckGenericArgsResult::Error; |
| } |
| |
| continue; |
| } |
| |
| case RequirementKind::Superclass: |
| // Superclass requirements. |
| if (!isSubtypeOf(firstType, secondType, dc)) { |
| // FIXME: Poor source-location information. |
| diagnose(loc, diag::type_does_not_inherit, owner, firstType, |
| secondType); |
| |
| diagnose(noteLoc, diag::type_does_not_inherit_requirement, |
| req.getFirstType(), req.getSecondType(), |
| gatherGenericParamBindingsText( |
| {req.getFirstType(), req.getSecondType()}, |
| genericSig, substitutions)); |
| return CheckGenericArgsResult::Error; |
| } |
| continue; |
| |
| case RequirementKind::SameType: |
| if (!firstType->isEqual(secondType)) { |
| // FIXME: Better location info for both diagnostics. |
| diagnose(loc, diag::types_not_equal, owner, firstType, secondType); |
| |
| diagnose(noteLoc, diag::types_not_equal_requirement, |
| req.getFirstType(), req.getSecondType(), |
| gatherGenericParamBindingsText( |
| {req.getFirstType(), req.getSecondType()}, |
| genericSig, substitutions)); |
| return CheckGenericArgsResult::Error; |
| } |
| continue; |
| } |
| } |
| |
| return CheckGenericArgsResult::Success; |
| } |
| |
| Type TypeChecker::getWitnessType(Type type, ProtocolDecl *protocol, |
| ProtocolConformanceRef conformance, |
| Identifier name, |
| Diag<> brokenProtocolDiag) { |
| Type ty = ProtocolConformance::getTypeWitnessByName(type, conformance, |
| name, this); |
| if (!ty && |
| !(conformance.isConcrete() && conformance.getConcrete()->isInvalid())) |
| diagnose(protocol->getLoc(), brokenProtocolDiag); |
| |
| return ty; |
| } |