swiftlang · slavapestov · Dec 5, 2016 · Dec 4, 2016 · Dec 4, 2016 · Dec 5, 2016
diff --git a/include/swift/AST/Decl.h b/include/swift/AST/Decl.h
@@ -4580,10 +4580,6 @@ class AbstractFunctionDecl : public ValueDecl, public DeclContext {
   // FIXME: Hack that provides names with keyword arguments for accessors.
   DeclName getEffectiveFullName() const;
 
-  /// \brief If this is a method in a type extension for some type,
-  /// return that type, otherwise return Type().
-  Type getExtensionType() const;
-
   /// Returns true if the function has a body written in the source file.
   ///
   /// Note that a true return value does not imply that the body was actually

diff --git a/include/swift/AST/DiagnosticsParse.def b/include/swift/AST/DiagnosticsParse.def
@@ -508,7 +508,8 @@ ERROR(sil_member_lookup_bad_type,none,
 ERROR(sil_member_decl_type_mismatch,none,
       "member defined with mismatching type %0 (expected %1)", (Type, Type))
 ERROR(sil_substitution_mismatch,none,
-      "substitution conformances don't match archetype", ())
+      "substitution replacement type %0 does not conform to protocol %1",
+      (Type, DeclName))
 ERROR(sil_missing_substitutions,none,
       "missing substitutions", ())
 ERROR(sil_too_many_substitutions,none,

diff --git a/include/swift/AST/Types.h b/include/swift/AST/Types.h
@@ -916,9 +916,6 @@ class alignas(1 << TypeAlignInBits) TypeBase {
 
   /// Whether this is the AnyObject type.
   bool isAnyObject();
-
-  /// Whether this is an empty existential composition ("{}").
-  bool isEmptyExistentialComposition();
 
   /// Whether this is an existential composition containing
   /// Error.
@@ -938,16 +935,6 @@ class alignas(1 << TypeAlignInBits) TypeBase {
   /// Return whether this type is or can be substituted for a bridgeable
   /// object type.
   TypeTraitResult canBeClass();
-
-  /// Returns true if the type conforms to protocols using witnesses from the
-  /// environment or from within the value. Generic parameters and existentials
-  /// meet this criteria. In these cases we represent the
-  /// conformance as a null ProtocolConformance* pointer, because there is no
-  /// static conformance associated with the conforming type.
-  bool hasDependentProtocolConformances();
-
-  /// Retrieve the type declaration directly referenced by this type, if any.
-  TypeDecl *getDirectlyReferencedTypeDecl() const;
 
 private:
   // Make vanilla new/delete illegal for Types.
@@ -4618,11 +4605,6 @@ inline CanType Type::getCanonicalTypeOrNull() const {
   return isNull() ? CanType() : getPointer()->getCanonicalType();
 }
 
-inline bool TypeBase::hasDependentProtocolConformances() {
-  return is<SubstitutableType>() || is<GenericTypeParamType>()
-      || isAnyExistentialType();
-}
-
 #define TYPE(id, parent)
 #define SUGARED_TYPE(id, parent) \
 template <> \

diff --git a/lib/AST/ASTVerifier.cpp b/lib/AST/ASTVerifier.cpp
@@ -2005,7 +2005,7 @@ struct ASTNodeBase {};
     void verifyChecked(ConstructorDecl *CD) {
       PrettyStackTraceDecl debugStack("verifying ConstructorDecl", CD);
 
-      auto *ND = CD->getExtensionType()->getNominalOrBoundGenericNominal();
+      auto *ND = CD->getDeclContext()->getAsNominalTypeOrNominalTypeExtensionContext();
       if (!isa<ClassDecl>(ND) && !isa<StructDecl>(ND) && !isa<EnumDecl>(ND) &&
           !isa<ProtocolDecl>(ND) && !CD->isInvalid()) {
         Out << "ConstructorDecls outside structs, classes or enums "
@@ -2188,7 +2188,7 @@ struct ASTNodeBase {};
     void verifyChecked(DestructorDecl *DD) {
       PrettyStackTraceDecl debugStack("verifying DestructorDecl", DD);
 
-      auto *ND = DD->getExtensionType()->getNominalOrBoundGenericNominal();
+      auto *ND = DD->getDeclContext()->getAsNominalTypeOrNominalTypeExtensionContext();
       if (!isa<ClassDecl>(ND) && !DD->isInvalid()) {
         Out << "DestructorDecls outside classes should be marked invalid";
         abort();

diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
@@ -2935,7 +2935,7 @@ bool AbstractStorageDecl::isGetterMutating() const {
 /// called even on an immutable base value.
 bool AbstractStorageDecl::isSetterNonMutating() const {
   // Setters declared in reference type contexts are never mutating.
-  if (auto contextType = getDeclContext()->getDeclaredTypeInContext()) {
+  if (auto contextType = getDeclContext()->getDeclaredInterfaceType()) {
     if (contextType->hasReferenceSemantics())
       return true;
   }
@@ -3608,7 +3608,7 @@ void VarDecl::emitLetToVarNoteIfSimple(DeclContext *UseDC) const {
     // a property in a non-mutating method.
     auto FD = dyn_cast_or_null<FuncDecl>(UseDC->getInnermostMethodContext());
     if (FD && !FD->isMutating() && !FD->isImplicit() && FD->isInstanceMember()&&
-        !FD->getDeclContext()->getDeclaredTypeInContext()
+        !FD->getDeclContext()->getDeclaredInterfaceType()
                  ->hasReferenceSemantics()) {
       auto &d = getASTContext().Diags;
       d.diagnose(FD->getFuncLoc(), diag::change_to_mutating, FD->isAccessor())
@@ -4030,10 +4030,6 @@ ParamDecl *AbstractFunctionDecl::getImplicitSelfDecl() {
   return nullptr;
 }
 
-Type AbstractFunctionDecl::getExtensionType() const {
-  return getDeclContext()->getDeclaredTypeInContext();
-}
-
 std::pair<DefaultArgumentKind, Type>
 AbstractFunctionDecl::getDefaultArg(unsigned Index) const {
   auto paramLists = getParameterLists();
@@ -4323,7 +4319,7 @@ bool FuncDecl::isExplicitNonMutating() const {
   return !isMutating() &&
          isAccessor() && !isGetter() &&
          isInstanceMember() &&
-         !getDeclContext()->getDeclaredTypeInContext()->hasReferenceSemantics();
+         !getDeclContext()->getDeclaredInterfaceType()->hasReferenceSemantics();
 }
 
 void FuncDecl::setDeserializedSignature(ArrayRef<ParameterList *> BodyParams,

diff --git a/lib/AST/LookupVisibleDecls.cpp b/lib/AST/LookupVisibleDecls.cpp
@@ -827,14 +827,11 @@ void swift::lookupVisibleDecls(VisibleDeclConsumer &Consumer,
         Consumer.foundDecl(const_cast<ParamDecl*>(AFD->getImplicitSelfDecl()),
                            DeclVisibilityKind::FunctionParameter);
 
-      if (AFD->getExtensionType()) {
-        ExtendedType = AFD->getExtensionType();
+      if (AFD->getDeclContext()->isTypeContext()) {
+        ExtendedType = AFD->getDeclContext()->getSelfTypeInContext();
         BaseDecl = AFD->getImplicitSelfDecl();
         DC = DC->getParent();
 
-        if (DC->getAsProtocolExtensionContext())
-          ExtendedType = DC->getSelfTypeInContext();
-
         if (auto *FD = dyn_cast<FuncDecl>(AFD))
           if (FD->isStatic())
             ExtendedType = MetatypeType::get(ExtendedType);

diff --git a/lib/AST/NameLookup.cpp b/lib/AST/NameLookup.cpp
@@ -197,7 +197,8 @@ bool swift::removeShadowedDecls(SmallVectorImpl<ValueDecl*> &decls,
     if (decl->hasClangNode()) {
       if (auto ctor = dyn_cast<ConstructorDecl>(decl)) {
         auto ctorSignature
-          = std::make_pair(ctor->getExtensionType()->getCanonicalType(),
+          = std::make_pair(ctor->getDeclContext()->getDeclaredInterfaceType()
+                               ->getCanonicalType(),
                            decl->getFullName());
         auto &knownCtors = ObjCCollidingConstructors[ctorSignature];
         if (!knownCtors.empty())
@@ -722,18 +723,17 @@ UnqualifiedLookup::UnqualifiedLookup(DeclName Name, DeclContext *DC,
           if (!isCascadingUse.hasValue() || isCascadingUse.getValue())
             isCascadingUse = AFD->isCascadingContextForLookup(false);
 
-          if (AFD->getExtensionType()) {
-            if (AFD->getDeclContext()->getAsProtocolOrProtocolExtensionContext()) {
-              ExtendedType = AFD->getDeclContext()->getSelfTypeInContext();
+          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();
 
-              // Fallback path.
-              if (!ExtendedType)
-                ExtendedType = AFD->getExtensionType();
-            } else {
-              ExtendedType = AFD->getExtensionType();
-            }
             BaseDecl = AFD->getImplicitSelfDecl();
-            MetaBaseDecl = AFD->getExtensionType()->getAnyNominal();
+            MetaBaseDecl = AFD->getDeclContext()
+                ->getAsNominalTypeOrNominalTypeExtensionContext();
             DC = DC->getParent();
 
             if (auto *FD = dyn_cast<FuncDecl>(AFD))

diff --git a/lib/AST/Substitution.cpp b/lib/AST/Substitution.cpp
@@ -92,15 +92,10 @@ Substitution Substitution::subst(Module *module,
       conformance = ProtocolConformanceRef(lookupResults.front());
     }
 
-    if (conformance) {
-      if (conformance->isConcrete())
-        conformancesChanged = true;
-      substConformances.push_back(*conformance);
-    } else {
-      assert(substReplacement->hasDependentProtocolConformances() &&
-             "couldn't find concrete conformance for concrete type?");
-      substConformances.push_back(ProtocolConformanceRef(proto));
-    }
+    assert(conformance);
+    if (conformance->isConcrete())
+      conformancesChanged = true;
+    substConformances.push_back(*conformance);
   }
   assert(substConformances.size() == Conformance.size());
 

diff --git a/lib/AST/Type.cpp b/lib/AST/Type.cpp
@@ -659,17 +659,6 @@ bool TypeBase::isAnyObject() {
   return false;
 }
 
-bool TypeBase::isEmptyExistentialComposition() {
-  if (auto emtType = ExistentialMetatypeType::get(this)) {
-    if (auto pcType = emtType->getInstanceType()->
-        getAs<ProtocolCompositionType>()) {
-      return pcType->getProtocols().empty();
-    }
-  }
-
-  return false;
-}
-
 bool TypeBase::isExistentialWithError() {
   // FIXME: Compute this as a bit in TypeBase so this operation isn't
   // overly expensive.
@@ -955,38 +944,6 @@ Type TypeBase::getRValueInstanceType() {
   return type->getInOutObjectType();
 }
 
-TypeDecl *TypeBase::getDirectlyReferencedTypeDecl() const {
-  if (auto module = dyn_cast<ModuleType>(this))
-    return module->getModule();
-
-  if (auto nominal = dyn_cast<NominalType>(this))
-    return nominal->getDecl();
-
-  if (auto bound = dyn_cast<BoundGenericType>(this))
-    return bound->getDecl();
-
-  if (auto unbound = dyn_cast<UnboundGenericType>(this))
-    return unbound->getDecl();
-
-  if (auto alias = dyn_cast<NameAliasType>(this))
-    return alias->getDecl();
-
-  if (auto gp = dyn_cast<GenericTypeParamType>(this))
-    return gp->getDecl();
-
-  if (auto depMem = dyn_cast<DependentMemberType>(this))
-    return depMem->getAssocType();
-
-  if (auto archetype = dyn_cast<ArchetypeType>(this)) {
-    if (auto assoc = archetype->getAssocType())
-      return assoc;
-
-    return nullptr;
-  }
-
-  return nullptr;
-}
-
 /// \brief Collect the protocols in the existential type T into the given
 /// vector.
 static void addProtocols(Type T, SmallVectorImpl<ProtocolDecl *> &Protocols) {

diff --git a/lib/ClangImporter/ImportDecl.cpp b/lib/ClangImporter/ImportDecl.cpp
@@ -5414,7 +5414,8 @@ ConstructorDecl *SwiftDeclConverter::importConstructor(
 
 void SwiftDeclConverter::recordObjCOverride(AbstractFunctionDecl *decl) {
   // Figure out the class in which this method occurs.
-  auto classTy = decl->getExtensionType()->getAs<ClassType>();
+  auto classTy = decl->getDeclContext()->getDeclaredInterfaceType()
+      ->getAs<ClassType>();
   if (!classTy)
     return;
   auto superTy = classTy->getSuperclass(nullptr);

diff --git a/lib/Index/Index.cpp b/lib/Index/Index.cpp
@@ -575,8 +575,7 @@ bool IndexSwiftASTWalker::passRelatedType(const TypeLoc &Ty) {
   }
 
   if (Ty.getType()) {
-    if (auto nominal = dyn_cast_or_null<NominalTypeDecl>(
-            Ty.getType()->getDirectlyReferencedTypeDecl()))
+    if (auto nominal = Ty.getType()->getAnyNominal())
       if (!passRelated(nominal, Ty.getLoc()))
         return false;
   }
@@ -644,8 +643,7 @@ bool IndexSwiftASTWalker::reportPseudoAccessor(AbstractStorageDecl *D,
 NominalTypeDecl *
 IndexSwiftASTWalker::getTypeLocAsNominalTypeDecl(const TypeLoc &Ty) {
   if (Type T = Ty.getType())
-    return dyn_cast_or_null<NominalTypeDecl>(
-        T->getDirectlyReferencedTypeDecl());
+    return T->getAnyNominal();
   if (IdentTypeRepr *T = dyn_cast_or_null<IdentTypeRepr>(Ty.getTypeRepr())) {
     auto Comp = T->getComponentRange().back();
     if (auto NTD = dyn_cast_or_null<NominalTypeDecl>(Comp->getBoundDecl()))