diff --git a/include/swift/AST/ASTContext.h b/include/swift/AST/ASTContext.h
index 1937e57..7cec457 100644
--- a/include/swift/AST/ASTContext.h
+++ b/include/swift/AST/ASTContext.h
@@ -850,15 +850,6 @@
                                        GenericSignature *sig,
                                        ModuleDecl &module);
 
-  /// Retrieve the inherited name set for the given class.
-  const InheritedNameSet *getAllPropertyNames(ClassDecl *classDecl,
-                                              bool forInstance);
-
-  /// Retrieve the inherited name set for the given Objective-C class.
-  const InheritedNameSet *getAllPropertyNames(
-                            clang::ObjCInterfaceDecl *classDecl,
-                            bool forInstance);
-
   /// Retrieve a generic signature with a single unconstrained type parameter,
   /// like `<T>`.
   CanGenericSignature getSingleGenericParameterSignature() const;
diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index 2bb7bb5..292f4d7 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -247,16 +247,6 @@
   /// The keys are the generic signature builders in \c GenericSignatureBuilders.
   llvm::DenseMap<GenericSignatureBuilder *, GenericEnvironment *>
     CanonicalGenericEnvironments;
-
-  /// The set of property names that show up in the defining module of a
-  /// class.
-  llvm::DenseMap<std::pair<const ClassDecl *, char>,
-                 std::unique_ptr<InheritedNameSet>> AllProperties;
-
-  /// The set of property names that show up in the defining module of
-  /// an Objective-C class.
-  llvm::DenseMap<std::pair<const clang::ObjCInterfaceDecl *, char>,
-                 std::unique_ptr<InheritedNameSet>> AllPropertiesObjC;
   
   /// The single-parameter generic signature with no constraints, <T>.
   CanGenericSignature SingleGenericParameterSignature;
@@ -4154,129 +4144,6 @@
   return Type();
 }
 
-const InheritedNameSet *ASTContext::getAllPropertyNames(ClassDecl *classDecl,
-                                                        bool forInstance) {
-  // If this class was defined in Objective-C, perform the lookup based on
-  // the Objective-C class.
-  if (auto objcClass = dyn_cast_or_null<clang::ObjCInterfaceDecl>(
-                         classDecl->getClangDecl())) {
-    return getAllPropertyNames(
-             const_cast<clang::ObjCInterfaceDecl *>(objcClass),
-             forInstance);
-  }
-
-  // If we already have this information, return it.
-  auto known = Impl.AllProperties.find({classDecl, forInstance});
-  if (known != Impl.AllProperties.end()) return known->second.get();
-
-  // Otherwise, get information from our superclass first.
-  if (auto resolver = getLazyResolver())
-    resolver->resolveSuperclass(classDecl);
-
-  const InheritedNameSet *parentSet = nullptr;
-  if (auto superclass = classDecl->getSuperclass()) {
-    if (auto superclassDecl = superclass->getClassOrBoundGenericClass()) {
-      parentSet = getAllPropertyNames(superclassDecl, forInstance);
-    }
-  }
-
-  // Create the set of properties.
-  known = Impl.AllProperties.insert(
-            { std::pair<const ClassDecl *, char>(classDecl, forInstance),
-              llvm::make_unique<InheritedNameSet>(parentSet) }).first;
-
-  // Local function to add properties from the given set.
-  auto addProperties = [&](DeclRange members) {
-    for (auto member : members) {
-      auto var = dyn_cast<VarDecl>(member);
-      if (!var || var->getName().empty()) continue;
-      if (var->isInstanceMember() != forInstance) continue;
-
-      known->second->add(var->getName().str());
-    }
-  };
-
-  // Collect property names from the class.
-  addProperties(classDecl->getMembers());
-
-  // Collect property names from all extensions in the same module as the class.
-  auto module = classDecl->getParentModule();
-  for (auto ext : classDecl->getExtensions()) {
-    if (ext->getParentModule() != module) continue;
-    addProperties(ext->getMembers());
-  }
-
-  return known->second.get();
-}
-
-const InheritedNameSet *ASTContext::getAllPropertyNames(
-                          clang::ObjCInterfaceDecl *classDecl,
-                          bool forInstance) {
-  classDecl = classDecl->getCanonicalDecl();
-
-  // If we already have this information, return it.
-  auto known = Impl.AllPropertiesObjC.find({classDecl, forInstance});
-  if (known != Impl.AllPropertiesObjC.end()) return known->second.get();
-
-  // Otherwise, get information from our superclass first.
-  const InheritedNameSet *parentSet = nullptr;
-  if (auto superclassDecl = classDecl->getSuperClass()) {
-    parentSet = getAllPropertyNames(superclassDecl, forInstance);
-  }
-
-  // Create the set of properties.
-  known = Impl.AllPropertiesObjC.insert(
-            { std::pair<const clang::ObjCInterfaceDecl *, char>(classDecl,
-                                                                forInstance),
-              llvm::make_unique<InheritedNameSet>(parentSet) }).first;
-
-  // Local function to add properties from the given set.
-  auto addProperties = [&](clang::DeclContext::decl_range members) {
-    for (auto member : members) {
-      // Add Objective-C property names.
-      if (auto property = dyn_cast<clang::ObjCPropertyDecl>(member)) {
-        if (forInstance)
-          known->second->add(property->getName());
-        continue;
-      }
-
-      // Add no-parameter, non-void method names.
-      if (auto method = dyn_cast<clang::ObjCMethodDecl>(member)) {
-        if (method->getSelector().isUnarySelector() &&
-            !method->getReturnType()->isVoidType() &&
-            !method->hasRelatedResultType() &&
-            method->isInstanceMethod() == forInstance) {
-          known->second->add(method->getSelector().getNameForSlot(0));
-          continue;
-        }
-      }
-    }
-  };
-
-  // Dig out the class definition.
-  auto classDef = classDecl->getDefinition();
-  if (!classDef) return known->second.get();
-
-  // Collect property names from the class definition.
-  addProperties(classDef->decls());
-
-  // Dig out the module that owns the class definition.
-  auto module = classDef->getImportedOwningModule();
-  if (module) module = module->getTopLevelModule();
-
-  // Collect property names from all categories and extensions in the same
-  // module as the class.
-  for (auto category : classDef->known_categories()) {
-    auto categoryModule = category->getImportedOwningModule();
-    if (categoryModule) categoryModule = categoryModule->getTopLevelModule();
-    if (module != categoryModule) continue;
-
-    addProperties(category->decls());
-  }
-
-  return known->second.get();
-}
-
 CanGenericSignature ASTContext::getSingleGenericParameterSignature() const {
   if (auto theSig = Impl.SingleGenericParameterSignature)
     return theSig;
diff --git a/lib/ClangImporter/ImportName.cpp b/lib/ClangImporter/ImportName.cpp
index 4506c95..eb00e0b 100644
--- a/lib/ClangImporter/ImportName.cpp
+++ b/lib/ClangImporter/ImportName.cpp
@@ -783,7 +783,7 @@
   if (!contextType.isNull()) {
     if (auto objcPtrType = contextType->getAsObjCInterfacePointerType())
       if (auto objcClassDecl = objcPtrType->getInterfaceDecl())
-        allPropertyNames = nameImporter.getContext().getAllPropertyNames(
+        allPropertyNames = nameImporter.getAllPropertyNames(
             objcClassDecl, isInstanceMethod);
   }
 
@@ -1596,8 +1596,7 @@
           if (auto objcPtrType = contextType->getAsObjCInterfacePointerType())
             if (auto objcClassDecl = objcPtrType->getInterfaceDecl())
               allPropertyNames =
-                  swiftCtx.getAllPropertyNames(objcClassDecl,
-                                               /*forInstance=*/true);
+                  getAllPropertyNames(objcClassDecl, /*forInstance=*/true);
         }
 
         (void)omitNeedlessWords(baseName, {}, "", propertyTypeName,
@@ -1716,3 +1715,72 @@
     importNameCache[key] = res;
   return res;
 }
+
+const InheritedNameSet *NameImporter::getAllPropertyNames(
+                          clang::ObjCInterfaceDecl *classDecl,
+                          bool forInstance) {
+  classDecl = classDecl->getCanonicalDecl();
+
+  // If we already have this information, return it.
+  auto known = allProperties.find({classDecl, forInstance});
+  if (known != allProperties.end()) return known->second.get();
+
+  // Otherwise, get information from our superclass first.
+  const InheritedNameSet *parentSet = nullptr;
+  if (auto superclassDecl = classDecl->getSuperClass()) {
+    parentSet = getAllPropertyNames(superclassDecl, forInstance);
+  }
+
+  // Create the set of properties.
+  known = allProperties.insert(
+            { std::pair<const clang::ObjCInterfaceDecl *, char>(classDecl,
+                                                                forInstance),
+              llvm::make_unique<InheritedNameSet>(parentSet) }).first;
+
+  // Local function to add properties from the given set.
+  auto addProperties = [&](clang::DeclContext::decl_range members) {
+    for (auto member : members) {
+      // Add Objective-C property names.
+      if (auto property = dyn_cast<clang::ObjCPropertyDecl>(member)) {
+        if (forInstance)
+          known->second->add(property->getName());
+        continue;
+      }
+
+      // Add no-parameter, non-void method names.
+      if (auto method = dyn_cast<clang::ObjCMethodDecl>(member)) {
+        if (method->getSelector().isUnarySelector() &&
+            !method->getReturnType()->isVoidType() &&
+            !method->hasRelatedResultType() &&
+            method->isInstanceMethod() == forInstance) {
+          known->second->add(method->getSelector().getNameForSlot(0));
+          continue;
+        }
+      }
+    }
+  };
+
+  // Dig out the class definition.
+  auto classDef = classDecl->getDefinition();
+  if (!classDef) return known->second.get();
+
+  // Collect property names from the class definition.
+  addProperties(classDef->decls());
+
+  // Dig out the module that owns the class definition.
+  auto module = classDef->getImportedOwningModule();
+  if (module) module = module->getTopLevelModule();
+
+  // Collect property names from all categories and extensions in the same
+  // module as the class.
+  for (auto category : classDef->known_categories()) {
+    auto categoryModule = category->getImportedOwningModule();
+    if (categoryModule) categoryModule = categoryModule->getTopLevelModule();
+    if (module != categoryModule) continue;
+
+    addProperties(category->decls());
+  }
+
+  return known->second.get();
+}
+
diff --git a/lib/ClangImporter/ImportName.h b/lib/ClangImporter/ImportName.h
index b8f33cc..2c37f5d 100644
--- a/lib/ClangImporter/ImportName.h
+++ b/lib/ClangImporter/ImportName.h
@@ -297,6 +297,11 @@
   /// Cache for repeated calls
   llvm::DenseMap<CacheKeyType, ImportedName> importNameCache;
 
+  /// The set of property names that show up in the defining module of
+  /// an Objective-C class.
+  llvm::DenseMap<std::pair<const clang::ObjCInterfaceDecl *, char>,
+                 std::unique_ptr<InheritedNameSet>> allProperties;
+
 public:
   NameImporter(ASTContext &ctx, const PlatformAvailability &avail,
                clang::Sema &cSema, bool inferIAM)
@@ -340,6 +345,11 @@
     return getClangSema().getPreprocessor();
   }
 
+  /// Retrieve the inherited name set for the given Objective-C class.
+  const InheritedNameSet *getAllPropertyNames(
+                            clang::ObjCInterfaceDecl *classDecl,
+                            bool forInstance);
+
 private:
   bool enableObjCInterop() const { return swiftCtx.LangOpts.EnableObjCInterop; }
 
diff --git a/lib/Sema/MiscDiagnostics.cpp b/lib/Sema/MiscDiagnostics.cpp
index 2c59d60..4c48d38 100644
--- a/lib/Sema/MiscDiagnostics.cpp
+++ b/lib/Sema/MiscDiagnostics.cpp
@@ -3861,21 +3861,12 @@
   if (params->size() != 0 && !params->get(0)->getName().empty())
     firstParamName = params->get(0)->getName().str();
 
-  // Find the set of property names.
-  const InheritedNameSet *allPropertyNames = nullptr;
-  if (contextType) {
-    if (auto classDecl = contextType->getClassOrBoundGenericClass()) {
-      allPropertyNames = Context.getAllPropertyNames(classDecl,
-                                                     afd->isInstanceMember());
-    }
-  }
-
   StringScratchSpace scratch;
   if (!swift::omitNeedlessWords(baseNameStr, argNameStrs, firstParamName,
                                 getTypeNameForOmission(resultType),
                                 getTypeNameForOmission(contextType),
                                 paramTypes, returnsSelf, false,
-                                allPropertyNames, scratch))
+                                /*allPropertyNames=*/nullptr, scratch))
     return None;
 
   /// Retrieve a replacement identifier.
@@ -3927,23 +3918,13 @@
   while (auto optObjectTy = type->getAnyOptionalObjectType())
     type = optObjectTy;
 
-  // Find the set of property names.
-  const InheritedNameSet *allPropertyNames = nullptr;
-  if (contextType) {
-    if (auto classDecl = contextType->getClassOrBoundGenericClass()) {
-      allPropertyNames = Context.getAllPropertyNames(classDecl,
-                                                     var->isInstanceMember());
-    }
-  }
-
-
   // Omit needless words.
   StringScratchSpace scratch;
   OmissionTypeName typeName = getTypeNameForOmission(var->getInterfaceType());
   OmissionTypeName contextTypeName = getTypeNameForOmission(contextType);
   if (::omitNeedlessWords(name, { }, "", typeName, contextTypeName, { },
-                          /*returnsSelf=*/false, true, allPropertyNames,
-                          scratch)) {
+                          /*returnsSelf=*/false, true,
+                          /*allPropertyNames=*/nullptr, scratch)) {
     return Context.getIdentifier(name);
   }