Merge pull request llvm#23944 from slavapestov/lazier-and-more-correct-metadata

Fix some problems with IRGen lazy metadata emission

Author: slavapestov

include/swift/IRGen/Linking.h

@@ -346,10 +346,6 @@ class LinkEntity {
     /// The pointer is a canonical TypeBase*.
     TypeMetadataLazyCacheVariable,
 
-    /// A foreign type metadata candidate.
-    /// The pointer is a canonical TypeBase*.
-    ForeignTypeMetadataCandidate,
-
     /// A reflection metadata descriptor for a builtin or imported type.
     ReflectionBuiltinDescriptor,
 
@@ -688,12 +684,6 @@ class LinkEntity {
     return entity;
   }
 
-  static LinkEntity forForeignTypeMetadataCandidate(CanType type) {
-    LinkEntity entity;
-    entity.setForType(Kind::ForeignTypeMetadataCandidate, type);
-    return entity;
-  }
-
   static LinkEntity forClassMetadataBaseOffset(ClassDecl *decl) {
     LinkEntity entity;
     entity.setForDecl(Kind::ClassMetadataBaseOffset, decl);
@@ -1047,15 +1037,15 @@ class LinkEntity {
            getKind() == Kind::ObjCResilientClassStub);
     return (TypeMetadataAddress)LINKENTITY_GET_FIELD(Data, MetadataAddress);
   }
-  bool isForeignTypeMetadataCandidate() const {
-    return getKind() == Kind::ForeignTypeMetadataCandidate;
-  }
   bool isObjCClassRef() const {
     return getKind() == Kind::ObjCClassRef;
   }
   bool isSILFunction() const {
     return getKind() == Kind::SILFunction;
   }
+  bool isNominalTypeDescriptor() const {
+    return getKind() == Kind::NominalTypeDescriptor;
+  }
 
   /// Determine whether this entity will be weak-imported.
   bool isWeakImported(ModuleDecl *module,

lib/IRGen/GenClass.cpp

@@ -930,13 +930,16 @@ void IRGenModule::emitClassDecl(ClassDecl *D) {
   auto &resilientLayout =
     classTI.getClassLayout(*this, selfType, /*forBackwardDeployment=*/false);
 
+  // As a matter of policy, class metadata is never emitted lazily for now.
+  assert(!IRGen.hasLazyMetadata(D));
+
   // Emit the class metadata.
   emitClassMetadata(*this, D, fragileLayout, resilientLayout);
+  emitFieldDescriptor(D);
 
   IRGen.addClassForEagerInitialization(D);
 
   emitNestedTypeDecls(D->getMembers());
-  emitFieldMetadataRecord(D);
 }
 
 namespace {