Merge pull request #15256 from slavapestov/stored-property-initializers-are-public-again

Stored property initializers are public again

Author: slavapestov

lib/SIL/SILDeclRef.cpp

@@ -285,19 +285,29 @@ SILLinkage SILDeclRef::getLinkage(ForDefinition_t forDefinition) const {
 
   // Stored property initializers get the linkage of their containing type.
   if (isStoredPropertyInitializer()) {
-    // If the type is public, the property initializer is referenced from
-    // inlinable initializers, and has PublicNonABI linkage.
+    // Three cases:
     //
-    // Note that we don't serialize the presence of an initializer, so there's
-    // no way to reference one from another module except for this case.
+    // 1) Type is formally @_fixed_layout. Root initializers can be declared
+    //    @_inlineable. The property initializer must only reference
+    //    public symbols, and is serialized, so we give it PublicNonABI linkage.
+    //
+    // 2) Type is not formally @_fixed_layout and the module is not resilient.
+    //    Root initializers can be declared @_inlineable. This is the annoying
+    //    case. We give the initializer public linkage if the type is public.
+    //
+    // 3) Type is resilient. The property initializer is never public because
+    //    root initializers cannot be @_inlineable.
+    //
+    // FIXME: Get rid of case 2 somehow.
     if (isSerialized())
       return maybeAddExternal(SILLinkage::PublicNonABI);
 
-    // Otherwise, use the visibility of the type itself, because even if the
-    // property is private, we might reference the initializer from another
-    // file.
     d = cast<NominalTypeDecl>(d->getDeclContext());
-    neverPublic = true;
+
+    // FIXME: This should always be true.
+    if (d->getDeclContext()->getParentModule()->getResilienceStrategy() ==
+        ResilienceStrategy::Resilient)
+      neverPublic = true;
   }
 
   // The global addressor is never public for resilient globals.

lib/TBDGen/TBDGen.cpp

@@ -40,6 +40,21 @@ static bool isGlobalOrStaticVar(VarDecl *VD) {
   return VD->isStatic() || VD->getDeclContext()->isModuleScopeContext();
 }
 
+void TBDGenVisitor::visitPatternBindingDecl(PatternBindingDecl *PBD) {
+  for (auto &entry : PBD->getPatternList()) {
+    auto *var = entry.getAnchoringVarDecl();
+
+    // Non-global variables might have an explicit initializer symbol.
+    if (entry.getInit() && !isGlobalOrStaticVar(var)) {
+      auto declRef =
+          SILDeclRef(var, SILDeclRef::Kind::StoredPropertyInitializer);
+      // Stored property initializers for public properties are currently
+      // public.
+      addSymbol(declRef);
+    }
+  }
+}
+
 void TBDGenVisitor::addSymbol(SILDeclRef declRef) {
   auto linkage = effectiveLinkageForClassMember(
     declRef.getLinkage(ForDefinition),

lib/TBDGen/TBDGenVisitor.h

@@ -84,6 +84,8 @@ class TBDGenVisitor : public ASTVisitor<TBDGenVisitor> {
       addSymbol("main");
   }
 
+  void visitPatternBindingDecl(PatternBindingDecl *PBD);
+
   void visitAbstractFunctionDecl(AbstractFunctionDecl *AFD);
 
   void visitNominalTypeDecl(NominalTypeDecl *NTD);

test/SILGen/extensions_multifile.swift

@@ -1,4 +1,5 @@
-// RUN: %target-swift-frontend -emit-silgen -primary-file %s %S/Inputs/struct_with_initializer.swift -module-name extensions_multifile -enable-sil-ownership | %FileCheck %s
+// RUN: %target-swift-frontend -emit-silgen -primary-file %s %S/Inputs/struct_with_initializer.swift -module-name extensions_multifile -enable-sil-ownership | %FileCheck %s --check-prefix=FRAGILE --check-prefix=CHECK
+// RUN: %target-swift-frontend -emit-silgen -primary-file %s %S/Inputs/struct_with_initializer.swift -module-name extensions_multifile -enable-sil-ownership -enable-resilience | %FileCheck %s --check-prefix=RESILIENT --check-prefix=CHECK
 
 // CHECK-LABEL: sil hidden @$S20extensions_multifile12HasInitValueV1zACSi_tcfC : $@convention(method) (Int, @thin HasInitValue.Type) -> @owned HasInitValue {
 // CHECK: function_ref @$S20extensions_multifile12HasInitValueV1xSivpfi : $@convention(thin) () -> Int
@@ -15,7 +16,9 @@ extension HasPrivateInitValue {
   init(z: Int) {}
 }
 
-// CHECK-LABEL: sil hidden_external [transparent] @$S20extensions_multifile24PublicStructHasInitValueV1xSivpfi : $@convention(thin) () -> Int
+// FRAGILE-LABEL: sil [transparent] @$S20extensions_multifile24PublicStructHasInitValueV1xSivpfi : $@convention(thin) () -> Int
+
+// RESILIENT-LABEL: sil hidden_external [transparent] @$S20extensions_multifile24PublicStructHasInitValueV1xSivpfi : $@convention(thin) () -> Int
 
 extension PublicStructHasInitValue {
   init(z: Int) {}

test/SILGen/fixed_layout_attribute.swift

@@ -20,7 +20,8 @@ public struct NonFixedStruct {
   public var storedProperty = global
 }
 
-// CHECK-LABEL: sil hidden [transparent] @$S22fixed_layout_attribute14NonFixedStructV14storedPropertySivpfi : $@convention(thin) () -> Int
+// FRAGILE-LABEL: sil [transparent] @$S22fixed_layout_attribute14NonFixedStructV14storedPropertySivpfi : $@convention(thin) () -> Int
+// RESILIENT-LABEL: sil hidden [transparent] @$S22fixed_layout_attribute14NonFixedStructV14storedPropertySivpfi : $@convention(thin) () -> Int
 //
 //    ... okay to directly reference the addressor here:
 // CHECK: function_ref @$S22fixed_layout_attribute6globalSivau