Merge pull request swiftlang#28750 from CodaFi/inherited-wealth

Don't re-force member loading in already-forced class hierarchies

Author: CodaFi

lib/ClangImporter/ClangImporter.cpp

@@ -3714,22 +3714,19 @@ void ClangImporter::Implementation::lookupAllObjCMembers(
   }
 }
 
-// Force the named member of the entire inheritance hierarchy to be loaded and
+// Force the members of the entire inheritance hierarchy to be loaded and
 // deserialized before loading the named member of this class. This allows the
 // decl members table to be warmed up and enables the correct identification of
 // overrides.
-static void loadNamedMemberOfSuperclassesIfNeeded(const ClassDecl *CD,
-                                                  DeclBaseName name) {
+static void ensureSuperclassMembersAreLoaded(const ClassDecl *CD) {
   if (!CD)
     return;
 
-  while ((CD = CD->getSuperclassDecl())) {
-    if (CD->hasClangNode()) {
-      auto ci = CD->getASTContext().getOrCreateLazyIterableContextData(
-          CD, /*lazyLoader=*/nullptr);
-      ci->loader->loadNamedMembers(CD, name, ci->memberData);
-    }
-  }
+  CD = CD->getSuperclassDecl();
+  if (!CD || !CD->hasClangNode())
+    return;
+  
+  CD->loadAllMembers();
 }
 
 Optional<TinyPtrVector<ValueDecl *>>
@@ -3793,7 +3790,7 @@ ClangImporter::Implementation::loadNamedMembers(
 
   assert(isa<clang::ObjCContainerDecl>(CD) || isa<clang::NamespaceDecl>(CD));
 
-  loadNamedMemberOfSuperclassesIfNeeded(dyn_cast<ClassDecl>(D), N);
+  ensureSuperclassMembersAreLoaded(dyn_cast<ClassDecl>(D));
 
   TinyPtrVector<ValueDecl *> Members;
   for (auto entry : table->lookup(SerializedSwiftName(N),

lib/ClangImporter/ImportDecl.cpp

@@ -8427,14 +8427,15 @@ createUnavailableDecl(Identifier name, DeclContext *dc, Type type,
 // deserialized before loading the members of this class. This allows the
 // decl members table to be warmed up and enables the correct identification of
 // overrides.
-static void loadAllMembersOfSuperclassesIfNeeded(const ClassDecl *CD) {
+static void loadAllMembersOfSuperclassIfNeeded(const ClassDecl *CD) {
   if (!CD)
     return;
 
-  while ((CD = CD->getSuperclassDecl())) {
-    if (CD->hasClangNode())
-      CD->loadAllMembers();
-  }
+  CD = CD->getSuperclassDecl();
+  if (!CD || !CD->hasClangNode())
+    return;
+
+  CD->loadAllMembers();
 }
 
 void
@@ -8449,7 +8450,7 @@ ClangImporter::Implementation::loadAllMembers(Decl *D, uint64_t extra) {
 
   // If not, we're importing globals-as-members into an extension.
   if (objcContainer) {
-    loadAllMembersOfSuperclassesIfNeeded(dyn_cast<ClassDecl>(D));
+    loadAllMembersOfSuperclassIfNeeded(dyn_cast<ClassDecl>(D));
     loadAllMembersOfObjcContainer(D, objcContainer);
     return;
   }

test/NameBinding/named_lazy_member_loading_objc_interface.swift

@@ -8,7 +8,7 @@
 // Check that named-lazy-member-loading reduces the number of Decls deserialized
 // RUN: %target-swift-frontend -typecheck -I %S/Inputs/NamedLazyMembers -disable-named-lazy-member-loading -stats-output-dir %t/stats-pre -primary-file %s %S/Inputs/NamedLazyMembers/NamedLazyMembersExt.swift
 // RUN: %target-swift-frontend -typecheck -I %S/Inputs/NamedLazyMembers -stats-output-dir %t/stats-post -primary-file %s %S/Inputs/NamedLazyMembers/NamedLazyMembersExt.swift
-// RUN: %{python} %utils/process-stats-dir.py --evaluate-delta 'NumTotalClangImportedEntities < -10' %t/stats-pre %t/stats-post
+// RUN: %{python} %utils/process-stats-dir.py --evaluate-delta 'NumTotalClangImportedEntities <= -1' %t/stats-pre %t/stats-post
 
 import NamedLazyMembers