[Distributed] Complete remote actor resolve() implementation in SIL

include/swift/AST/Builtins.def

@@ -727,7 +727,7 @@ BUILTIN_MISC_OPERATION(InitializeDefaultActor, "initializeDefaultActor", "", Spe
 /// Destroy the default-actor instance in a default actor object.
 BUILTIN_MISC_OPERATION(DestroyDefaultActor, "destroyDefaultActor", "", Special)
 
-/// Initialize a "proxy" for a distributed remote actor.
+/// Allocate a "proxy" for a distributed remote actor.  TODO(distributed) change the name of this to create throughout.
 BUILTIN_MISC_OPERATION(InitializeDistributedRemoteActor,
                        "initializeDistributedRemoteActor", "", Special)
 

include/swift/AST/Decl.h

@@ -403,10 +403,13 @@ class alignas(1 << DeclAlignInBits) Decl {
   SWIFT_INLINE_BITFIELD(SubscriptDecl, VarDecl, 2,
     StaticSpelling : 2
   );
-  SWIFT_INLINE_BITFIELD(AbstractFunctionDecl, ValueDecl, 3+8+1+1+1+1+1+1,
+  SWIFT_INLINE_BITFIELD(AbstractFunctionDecl, ValueDecl, 3+2+8+1+1+1+1+1+1,
     /// \see AbstractFunctionDecl::BodyKind
     BodyKind : 3,
 
+    /// \see AbstractFunctionDecl::SILSynthesizeKind
+    SILSynthesizeKind : 2,
+
     /// Import as member status.
     IAMStatus : 8,
 
@@ -3367,8 +3370,6 @@ class NominalTypeDecl : public GenericTypeDecl, public IterableDeclContext {
   /// for types that are not global actors.
   VarDecl *getGlobalActorInstance() const;
 
-  bool hasDistributedActorLocalInitializer() const;
-
   /// Whether this type is a global actor, which can be used as an
   /// attribute to decorate declarations for inclusion in the actor-isolated
   /// state denoted by this type.
@@ -5769,6 +5770,15 @@ class AbstractFunctionDecl : public GenericContext, public ValueDecl {
   friend class NeedsNewVTableEntryRequest;
 
 public:
+  /// records the kind of SILGen-synthesized body this decl represents
+  enum class SILSynthesizeKind {
+    None,
+    MemberwiseInitializer,
+    DistributedActorFactory
+
+    // This enum currently needs to fit in a 2-bit bitfield.
+  };
+
   enum class BodyKind {
     /// The function did not have a body in the source code file.
     None,
@@ -5788,8 +5798,8 @@ class AbstractFunctionDecl : public GenericContext, public ValueDecl {
     /// Function body is present and type-checked.
     TypeChecked,
 
-    /// This is a memberwise initializer that will be synthesized by SILGen.
-    MemberwiseInitializer,
+    // Function body will be synthesized by SILGen.
+    SILSynthesize,
 
     /// Function body text was deserialized from a .swiftmodule.
     Deserialized
@@ -5889,6 +5899,14 @@ class AbstractFunctionDecl : public GenericContext, public ValueDecl {
     Bits.AbstractFunctionDecl.BodyKind = unsigned(K);
   }
 
+  void setSILSynthesizeKind(SILSynthesizeKind K) {
+    Bits.AbstractFunctionDecl.SILSynthesizeKind = unsigned(K);
+  }
+
+  SILSynthesizeKind getSILSynthesizeKind() const {
+    return SILSynthesizeKind(Bits.AbstractFunctionDecl.SILSynthesizeKind);
+  }
+
 public:
   void setHasSingleExpressionBody(bool Has = true) { 
     Bits.AbstractFunctionDecl.HasSingleExpressionBody = Has;
@@ -6065,7 +6083,17 @@ class AbstractFunctionDecl : public GenericContext, public ValueDecl {
   void setIsMemberwiseInitializer() {
     assert(getBodyKind() == BodyKind::None);
     assert(isa<ConstructorDecl>(this));
-    setBodyKind(BodyKind::MemberwiseInitializer);
+    setBodyKind(BodyKind::SILSynthesize);
+    setSILSynthesizeKind(SILSynthesizeKind::MemberwiseInitializer);
+  }
+
+  /// Mark that the body should be filled in to be a factory method for creating
+  /// a distributed actor.
+  void setDistributedActorFactory() {
+    assert(getBodyKind() == BodyKind::None);
+    assert(isa<FuncDecl>(this));
+    setBodyKind(BodyKind::SILSynthesize);
+    setSILSynthesizeKind(SILSynthesizeKind::DistributedActorFactory);
   }
 
   /// Gets the body of this function, stripping the unused portions of #if
@@ -6089,7 +6117,16 @@ class AbstractFunctionDecl : public GenericContext, public ValueDecl {
   }
 
   bool isMemberwiseInitializer() const {
-    return getBodyKind() == BodyKind::MemberwiseInitializer;
+    return getBodyKind() == BodyKind::SILSynthesize
+        && getSILSynthesizeKind() == SILSynthesizeKind::MemberwiseInitializer;
+  }
+
+  /// Determines whether this function represents a distributed actor
+  /// initialization factory. Such functions do not have a body that is
+  /// representable in the AST, so it must be synthesized during SILGen.
+  bool isDistributedActorFactory() const {
+    return getBodyKind() == BodyKind::SILSynthesize
+    && getSILSynthesizeKind() == SILSynthesizeKind::DistributedActorFactory;
   }
 
   /// For a method of a class, checks whether it will require a new entry in the
@@ -6999,18 +7036,6 @@ class ConstructorDecl : public AbstractFunctionDecl {
   /// \endcode
   bool isObjCZeroParameterWithLongSelector() const;
 
-  /// Checks if the initializer is a distributed actor's 'local' initializer:
-  /// ```
-  /// init(transport: ActorTransport)
-  /// ```
-  bool isDistributedActorLocalInit() const;
-
-  /// Checks if the initializer is a distributed actor's 'resolve' initializer:
-  /// ```
-  /// init(resolve address: ActorAddress, using transport: ActorTransport)
-  /// ```
-  bool isDistributedActorResolveInit() const;
-
   static bool classof(const Decl *D) {
     return D->getKind() == DeclKind::Constructor;
   }

include/swift/AST/DiagnosticsSema.def

@@ -4558,27 +4558,6 @@ ERROR(actor_instance_property_wrapper,none,
 ERROR(distributed_actor_func_defined_outside_of_distributed_actor,none,
       "distributed function %0 is declared outside of an distributed actor",
       (DeclName))
-ERROR(distributed_actor_local_init_explicitly_defined,none,
-      "'distributed actor' local-initializer 'init(transport:)' "
-      "cannot be implemented explicitly.",
-      ())
-ERROR(distributed_actor_init_resolve_must_not_be_user_defined,none,
-      "'distributed actor' resolve-initializer 'init(resolve:using:)' "
-      "cannot be implemented explicitly.",
-      ())
-ERROR(distributed_actor_init_user_defined_must_be_convenience,none,
-      "'distributed actor' initializer %0 must be 'convenience' initializer. "
-      "Distributed actors have an implicitly synthesized designated "
-      "'init(transport:)' local-initializer, which other initializers must delegate to",
-      (DeclName))
-ERROR(distributed_actor_init_must_delegate_to_local_init,none,
-      "'distributed actor' initializer %0 must (directly or indirectly) delegate "
-      "to 'init(transport:)'",
-      (DeclName))
-ERROR(distributed_actor_init_must_not_delegate_to_resolve_init,none,
-      "'distributed actor' initializer %0 cannot delegate to resolve-initializer "
-      "'init(resolve:using:)', as it may result resolving a storageless proxy instance",
-      (DeclName))
 ERROR(distributed_actor_local_var,none,
       "'distributed' can not be applied to local variables",
       ())
@@ -4602,6 +4581,18 @@ ERROR(distributed_actor_func_static,none,
 ERROR(distributed_actor_func_not_in_distributed_actor,none,
       "'distributed' function can only be declared within 'distributed actor'",
       ())
+ERROR(distributed_actor_designated_ctor_must_have_one_transport_param,none,
+      "designated distributed actor initializer %0 must accept exactly one "
+      "ActorTransport parameter, found %1",
+      (DeclName, int))
+ERROR(distributed_actor_designated_ctor_missing_transport_param,none,
+      "designated distributed actor initializer %0 is missing required "
+      "ActorTransport parameter",
+      (DeclName))
+ERROR(distributed_actor_user_defined_special_property,none,
+      "property %0 cannot be defined explicitly, as it conflicts with "
+      "distributed actor synthesized stored property",
+      (DeclName))
 ERROR(distributed_actor_independent_property_must_be_let,none,
       "_distributedActorIndependent can be applied to properties, however they must be 'let'",
       ())

include/swift/AST/KnownIdentifiers.def

@@ -258,6 +258,7 @@ IDENTIFIER(assignIdentity)
 IDENTIFIER(resignIdentity)
 IDENTIFIER(resolve)
 IDENTIFIER(id)
+IDENTIFIER(identity)
 IDENTIFIER(identifier)
 IDENTIFIER(_distributedActorRemoteInitialize)
 IDENTIFIER(_distributedActorDestroy)

include/swift/AST/KnownProtocols.def

@@ -96,6 +96,7 @@ PROTOCOL(Differentiable)
 
 // Distributed Actors
 PROTOCOL(DistributedActor)
+PROTOCOL(ActorIdentity)
 PROTOCOL(ActorTransport)
 
 PROTOCOL(AsyncSequence)

include/swift/AST/TypeCheckRequests.h

@@ -1955,24 +1955,6 @@ class HasDefaultInitRequest
   bool isCached() const { return true; }
 };
 
-/// Checks whether this type has a distributed actor "local" initializer.
-class HasDistributedActorLocalInitRequest
-    : public SimpleRequest<HasDistributedActorLocalInitRequest, bool(NominalTypeDecl *),
-                           RequestFlags::Cached> {
-public:
-  using SimpleRequest::SimpleRequest;
-
-private:
-  friend SimpleRequest;
-
-  // Evaluation.
-  bool evaluate(Evaluator &evaluator, NominalTypeDecl *decl) const;
-
-public:
-  // Caching.
-  bool isCached() const { return true; }
-};
-
 /// Synthesizes a default initializer for a given type.
 class SynthesizeDefaultInitRequest
     : public SimpleRequest<SynthesizeDefaultInitRequest,
@@ -2065,6 +2047,7 @@ enum class ImplicitMemberAction : uint8_t {
   ResolveDecodable,
   ResolveDistributedActor,
   ResolveDistributedActorIdentity,
+  ResolveDistributedActorTransport,
 };
 
 class ResolveImplicitMemberRequest
@@ -2249,6 +2232,24 @@ class HasCircularRawValueRequest
   bool isCached() const { return true; }
 };
 
+/// Checks if the _Distributed module is available.
+class DistributedModuleIsAvailableRequest
+    : public SimpleRequest<DistributedModuleIsAvailableRequest, bool(Decl *),
+                           RequestFlags::Cached> {
+public:
+  using SimpleRequest::SimpleRequest;
+
+private:
+  friend SimpleRequest;
+
+  // Evaluation.
+  bool evaluate(Evaluator &evaluator, Decl *decl) const;
+
+public:
+  // Cached.
+  bool isCached() const { return true; }
+};
+
 /// Computes an initializer context for a parameter with a default argument.
 class DefaultArgumentInitContextRequest
     : public SimpleRequest<DefaultArgumentInitContextRequest,

include/swift/AST/TypeCheckerTypeIDZone.def

@@ -100,8 +100,6 @@ SWIFT_REQUEST(TypeChecker, IsDefaultActorRequest,
               Cached, NoLocationInfo)
 SWIFT_REQUEST(TypeChecker, IsDistributedActorRequest, bool(NominalTypeDecl *),
               Cached, NoLocationInfo)
-SWIFT_REQUEST(TypeChecker, HasDistributedActorLocalInitRequest,
-              bool(NominalTypeDecl *), Cached, NoLocationInfo)
 SWIFT_REQUEST(TypeChecker, IsDistributedFuncRequest, bool(FuncDecl *),
               Cached, NoLocationInfo)
 SWIFT_REQUEST(TypeChecker, GlobalActorInstanceRequest,
@@ -140,6 +138,8 @@ SWIFT_REQUEST(TypeChecker, InferredGenericSignatureRequest,
                                  SmallVector<Requirement, 2>,
                                  SmallVector<TypeLoc, 2>, bool),
               Cached, NoLocationInfo)
+SWIFT_REQUEST(TypeChecker, DistributedModuleIsAvailableRequest,
+              bool(ModuleDecl *), Cached, NoLocationInfo)
 SWIFT_REQUEST(TypeChecker, InheritedTypeRequest,
               Type(llvm::PointerUnion<const TypeDecl *, const ExtensionDecl *>,
                    unsigned, TypeResolutionStage),

include/swift/Runtime/Concurrency.h

@@ -716,18 +716,9 @@ SWIFT_EXPORT_FROM(swift_Concurrency) SWIFT_CC(swift)
 void swift_defaultActor_deallocateResilient(HeapObject *actor);
 
 /// Initialize the runtime storage for a distributed remote actor.
-// TODO: this may end up being removed as we move to the "proxy creation" below
 SWIFT_EXPORT_FROM(swift_Concurrency) SWIFT_CC(swift)
-void swift_distributedActor_remote_initialize(DefaultActor *actor);
-
-/// Create a proxy object that will serve as remote distributed actor instance.
-SWIFT_EXPORT_FROM(swift_Concurrency) SWIFT_CC(swift)
-OpaqueValue* swift_distributedActor_remote_create(
-  /* +1 */OpaqueValue *identity,
-  /* +1 */OpaqueValue *transport
-  // metadata for identity
-  // metadata for transport
-);
+OpaqueValue*
+swift_distributedActor_remote_initialize(const Metadata *actorType);
 
 /// Destroy the runtime storage for a default actor.
 SWIFT_EXPORT_FROM(swift_Concurrency) SWIFT_CC(swift)

include/swift/Runtime/RuntimeFunctions.def

@@ -1687,22 +1687,14 @@ FUNCTION(DefaultActorDeallocateResilient,
          ARGS(RefCountedPtrTy),
          ATTRS(NoUnwind))
 
-// void swift_distributedActor_remote_initialize(DefaultActor *actor);
+// OpaqueValue* swift_distributedActor_remote_initialize(
+//    const Metadata *actorType
+// );
 FUNCTION(DistributedActorInitializeRemote,
          swift_distributedActor_remote_initialize, SwiftCC,
          ConcurrencyAvailability,
-         RETURNS(VoidTy),
-         ARGS(RefCountedPtrTy), // TODO also address and transport?
-         ATTRS(NoUnwind))
-
-// OpaqueValue* swift_distributedActor_remote_create(
-//     OpaqueValue *identity,
-//     OpaqueValue *transport);
-FUNCTION(DistributedActorRemoteCreate,
-         swift_distributedActor_remote_create, SwiftCC,
-         ConcurrencyAvailability,
-         RETURNS(OpaquePtrTy), // TODO: is this the right type here?
-         ARGS(OpaquePtrTy, OpaquePtrTy),
+         RETURNS(OpaquePtrTy),
+         ARGS(TypeMetadataPtrTy),
          ATTRS(NoUnwind))
 
 // void swift_distributedActor_destroy(DefaultActor *actor); // TODO: ProxyActor *proxy?

lib/AST/ASTContext.cpp

@@ -1040,6 +1040,8 @@ ProtocolDecl *ASTContext::getProtocol(KnownProtocolKind kind) const {
     M = getLoadedModule(Id_Concurrency);
     break;
   case KnownProtocolKind::DistributedActor:
+  case KnownProtocolKind::ActorTransport:
+  case KnownProtocolKind::ActorIdentity:
     M = getLoadedModule(Id_Distributed);
     break;
   default:

lib/AST/ASTVerifier.cpp

@@ -475,7 +475,7 @@ class Verifier : public ASTWalker {
       case AbstractFunctionDecl::BodyKind::None:
       case AbstractFunctionDecl::BodyKind::TypeChecked:
       case AbstractFunctionDecl::BodyKind::Skipped:
-      case AbstractFunctionDecl::BodyKind::MemberwiseInitializer:
+      case AbstractFunctionDecl::BodyKind::SILSynthesize:
       case AbstractFunctionDecl::BodyKind::Deserialized:
         return true;
 

lib/AST/Builtins.cpp

@@ -1462,10 +1462,18 @@ static ValueDecl *getDefaultActorInitDestroy(ASTContext &ctx,
                             _void);
 }
 
-static ValueDecl *getDistributedActorInitDestroy(ASTContext &ctx,
+static ValueDecl *getDistributedActorInitializeRemote(ASTContext &ctx,
+                                                      Identifier id) {
+  return getBuiltinFunction(ctx, id, _thin,
+                            _generics(_unrestricted), // TODO(distributed): restrict to DistributedActor
+                            _parameters(_metatype(_typeparam(0))),
+                            _rawPointer);
+}
+
+static ValueDecl *getDistributedActorDestroy(ASTContext &ctx,
                                                  Identifier id) {
   return getBuiltinFunction(ctx, id, _thin,
-                            _parameters(_nativeObject), // TODO: no idea if to pass more here?
+                            _parameters(_nativeObject),
                             _void);
 }
 
@@ -2808,8 +2816,10 @@ ValueDecl *swift::getBuiltinValueDecl(ASTContext &Context, Identifier Id) {
     return getDefaultActorInitDestroy(Context, Id);
 
   case BuiltinValueKind::InitializeDistributedRemoteActor:
+    return getDistributedActorInitializeRemote(Context, Id);
+
   case BuiltinValueKind::DestroyDistributedActor:
-    return getDistributedActorInitDestroy(Context, Id);
+    return getDistributedActorDestroy(Context, Id);
 
   case BuiltinValueKind::StartAsyncLet:
   case BuiltinValueKind::StartAsyncLetWithLocalBuffer: