Merge pull request #68567 from hborla/unify-actor-isolation

[Concurrency] Remove `ClosureActorIsolation`.

Author: hborla

include/swift/AST/ActorIsolation.h

@@ -31,18 +31,6 @@ class NominalTypeDecl;
 class SubstitutionMap;
 class AbstractFunctionDecl;
 class AbstractClosureExpr;
-class ClosureActorIsolation;
-
-/// Trampoline for AbstractClosureExpr::getActorIsolation.
-ClosureActorIsolation
-__AbstractClosureExpr_getActorIsolation(AbstractClosureExpr *CE);
-
-/// Returns a function reference to \c __AbstractClosureExpr_getActorIsolation.
-/// This is needed so we can use it as a default argument for
-/// \c getActorIsolationOfContext without knowing the layout of
-/// \c ClosureActorIsolation.
-llvm::function_ref<ClosureActorIsolation(AbstractClosureExpr *)>
-_getRef__AbstractClosureExpr_getActorIsolation();
 
 /// Determine whether the given types are (canonically) equal, declared here
 /// to avoid having to include Types.h.
@@ -83,23 +71,28 @@ class ActorIsolation {
 
 private:
   union {
-    NominalTypeDecl *actor;
+    llvm::PointerUnion<NominalTypeDecl *, VarDecl *> actorInstance;
     Type globalActor;
     void *pointer;
   };
   unsigned kind : 3;
   unsigned isolatedByPreconcurrency : 1;
   unsigned parameterIndex : 28;
 
-  ActorIsolation(Kind kind, NominalTypeDecl *actor, unsigned parameterIndex)
-      : actor(actor), kind(kind), isolatedByPreconcurrency(false),
-        parameterIndex(parameterIndex) { }
+  ActorIsolation(Kind kind, NominalTypeDecl *actor, unsigned parameterIndex);
+
+  ActorIsolation(Kind kind, VarDecl *capturedActor);
 
   ActorIsolation(Kind kind, Type globalActor)
       : globalActor(globalActor), kind(kind), isolatedByPreconcurrency(false),
         parameterIndex(0) { }
 
 public:
+  // No-argument constructor needed for DenseMap use in PostfixCompletion.cpp
+  explicit ActorIsolation(Kind kind = Unspecified)
+      : pointer(nullptr), kind(kind), isolatedByPreconcurrency(false),
+        parameterIndex(0) { }
+
   static ActorIsolation forUnspecified() {
     return ActorIsolation(Unspecified, nullptr);
   }
@@ -117,6 +110,10 @@ class ActorIsolation {
     return ActorIsolation(ActorInstance, actor, parameterIndex + 1);
   }
 
+  static ActorIsolation forActorInstanceCapture(VarDecl *capturedActor) {
+    return ActorIsolation(ActorInstance, capturedActor);
+  }
+
   static ActorIsolation forGlobalActor(Type globalActor, bool unsafe) {
     return ActorIsolation(
         unsafe ? GlobalActorUnsafe : GlobalActor, globalActor);
@@ -151,10 +148,9 @@ class ActorIsolation {
     }
   }
 
-  NominalTypeDecl *getActor() const {
-    assert(getKind() == ActorInstance);
-    return actor;
-  }
+  NominalTypeDecl *getActor() const;
+
+  VarDecl *getActorInstance() const;
 
   bool isGlobalActor() const {
     return getKind() == GlobalActor || getKind() == GlobalActorUnsafe;
@@ -200,7 +196,8 @@ class ActorIsolation {
       return true;
 
     case ActorInstance:
-      return lhs.actor == rhs.actor && lhs.parameterIndex == rhs.parameterIndex;
+      return (lhs.getActor() == rhs.getActor() &&
+              lhs.parameterIndex == rhs.parameterIndex);
 
     case GlobalActor:
     case GlobalActorUnsafe:
@@ -223,16 +220,19 @@ class ActorIsolation {
 /// Determine how the given value declaration is isolated.
 ActorIsolation getActorIsolation(ValueDecl *value);
 
+/// Trampoline for AbstractClosureExpr::getActorIsolation.
+ActorIsolation
+__AbstractClosureExpr_getActorIsolation(AbstractClosureExpr *CE);
+
 /// Determine how the given declaration context is isolated.
 /// \p getClosureActorIsolation allows the specification of actor isolation for
 /// closures that haven't been saved been saved to the AST yet. This is useful
 /// for solver-based code completion which doesn't modify the AST but stores the
 /// actor isolation of closures in the constraint system solution.
 ActorIsolation getActorIsolationOfContext(
     DeclContext *dc,
-    llvm::function_ref<ClosureActorIsolation(AbstractClosureExpr *)>
-        getClosureActorIsolation =
-            _getRef__AbstractClosureExpr_getActorIsolation());
+    llvm::function_ref<ActorIsolation(AbstractClosureExpr *)>
+        getClosureActorIsolation = __AbstractClosureExpr_getActorIsolation);
 
 /// Check if both the value, and context are isolated to the same actor.
 bool isSameActorIsolated(ValueDecl *value, DeclContext *dc);
@@ -256,9 +256,9 @@ bool usesFlowSensitiveIsolation(AbstractFunctionDecl const *fn);
 /// \return true if it is safe to drop the global-actor qualifier.
 bool safeToDropGlobalActor(
                 DeclContext *dc, Type globalActor, Type ty,
-                llvm::function_ref<ClosureActorIsolation(AbstractClosureExpr *)>
+                llvm::function_ref<ActorIsolation(AbstractClosureExpr *)>
                     getClosureActorIsolation =
-                        _getRef__AbstractClosureExpr_getActorIsolation());
+                        __AbstractClosureExpr_getActorIsolation);
 
 void simple_display(llvm::raw_ostream &out, const ActorIsolation &state);
 

include/swift/AST/Expr.h

@@ -3777,92 +3777,6 @@ class SequenceExpr final : public Expr,
   }
 };
 
-/// Actor isolation for a closure.
-class ClosureActorIsolation {
-public:
-  enum Kind {
-    /// The closure is not isolated to any actor.
-    Nonisolated,
-
-    /// The closure is tied to the actor instance described by the given
-    /// \c VarDecl*, which is the (captured) `self` of an actor.
-    ActorInstance,
-
-    /// The closure is tied to the global actor described by the given type.
-    GlobalActor,
-  };
-
-private:
-    /// The actor to which this closure is isolated, plus a bit indicating
-    /// whether the isolation was imposed by a preconcurrency declaration.
-    ///
-    /// There are three possible states for the pointer:
-    ///   - NULL: The closure is independent of any actor.
-    ///   - VarDecl*: The 'self' variable for the actor instance to which
-    ///     this closure is isolated. It will always have a type that conforms
-    ///     to the \c Actor protocol.
-    ///   - Type: The type of the global actor on which
-  llvm::PointerIntPair<llvm::PointerUnion<VarDecl *, Type>, 1, bool> storage;
-
-  ClosureActorIsolation(VarDecl *selfDecl, bool preconcurrency)
-      : storage(selfDecl, preconcurrency) { }
-  ClosureActorIsolation(Type globalActorType, bool preconcurrency)
-      : storage(globalActorType, preconcurrency) { }
-
-public:
-  ClosureActorIsolation(bool preconcurrency = false)
-      : storage(nullptr, preconcurrency) { }
-
-  static ClosureActorIsolation forNonisolated(bool preconcurrency) {
-    return ClosureActorIsolation(preconcurrency);
-  }
-
-  static ClosureActorIsolation forActorInstance(VarDecl *selfDecl,
-                                                bool preconcurrency) {
-    return ClosureActorIsolation(selfDecl, preconcurrency);
-  }
-
-  static ClosureActorIsolation forGlobalActor(Type globalActorType,
-                                              bool preconcurrency) {
-    return ClosureActorIsolation(globalActorType, preconcurrency);
-  }
-
-  /// Determine the kind of isolation.
-  Kind getKind() const {
-    if (storage.getPointer().isNull())
-      return Kind::Nonisolated;
-
-    if (storage.getPointer().is<VarDecl *>())
-      return Kind::ActorInstance;
-
-    return Kind::GlobalActor;
-  }
-
-  /// Whether the closure is isolated at all.
-  explicit operator bool() const {
-    return getKind() != Kind::Nonisolated;
-  }
-
-  /// Whether the closure is isolated at all.
-  operator Kind() const {
-    return getKind();
-  }
-
-  VarDecl *getActorInstance() const {
-    return storage.getPointer().dyn_cast<VarDecl *>();
-  }
-
-  Type getGlobalActor() const {
-    return storage.getPointer().dyn_cast<Type>();
-  }
-
-  bool preconcurrency() const {
-    return storage.getInt();
-  }
-
-  ActorIsolation getActorIsolation() const;
-};
-
 /// A base class for closure expressions.
 class AbstractClosureExpr : public DeclContext, public Expr {
   CaptureInfo Captures;
@@ -3871,14 +3785,15 @@ class AbstractClosureExpr : public DeclContext, public Expr {
   ParameterList *parameterList;
 
   /// Actor isolation of the closure.
-  ClosureActorIsolation actorIsolation;
+  ActorIsolation actorIsolation;
 
 public:
   AbstractClosureExpr(ExprKind Kind, Type FnType, bool Implicit,
                       DeclContext *Parent)
       : DeclContext(DeclContextKind::AbstractClosureExpr, Parent),
         Expr(Kind, Implicit, FnType),
-        parameterList(nullptr) {
+        parameterList(nullptr),
+        actorIsolation(ActorIsolation::forUnspecified()) {
     Bits.AbstractClosureExpr.Discriminator = InvalidDiscriminator;
   }
 
@@ -3951,9 +3866,11 @@ class AbstractClosureExpr : public DeclContext, public Expr {
   /// returns nullptr if the closure doesn't have a body
   BraceStmt *getBody() const;
 
-  ClosureActorIsolation getActorIsolation() const { return actorIsolation; }
+  ActorIsolation getActorIsolation() const {
+    return actorIsolation;
+  }
 
-  void setActorIsolation(ClosureActorIsolation actorIsolation) {
+  void setActorIsolation(ActorIsolation actorIsolation) {
     this->actorIsolation = actorIsolation;
   }
 

include/swift/IDE/CompletionLookup.h

@@ -131,7 +131,7 @@ class CompletionLookup final : public swift::VisibleDeclConsumer {
   bool CanCurrDeclContextHandleAsync = false;
   /// Actor isolations that were determined during constraint solving but that
   /// haven't been saved to the AST.
-  llvm::DenseMap<AbstractClosureExpr *, ClosureActorIsolation>
+  llvm::DenseMap<AbstractClosureExpr *, ActorIsolation>
       ClosureActorIsolations;
   bool HaveDot = false;
   bool IsUnwrappedOptional = false;
@@ -253,7 +253,7 @@ class CompletionLookup final : public swift::VisibleDeclConsumer {
   }
 
   void setClosureActorIsolations(
-      llvm::DenseMap<AbstractClosureExpr *, ClosureActorIsolation>
+      llvm::DenseMap<AbstractClosureExpr *, ActorIsolation>
           ClosureActorIsolations) {
     this->ClosureActorIsolations = ClosureActorIsolations;
   }

include/swift/IDE/PostfixCompletion.h

@@ -63,7 +63,7 @@ class PostfixCompletionCallback : public TypeCheckCompletionCallback {
 
     /// Actor isolations that were determined during constraint solving but that
     /// haven't been saved to the AST.
-    llvm::DenseMap<AbstractClosureExpr *, ClosureActorIsolation>
+    llvm::DenseMap<AbstractClosureExpr *, ActorIsolation>
         ClosureActorIsolations;
 
     /// Checks whether this result has the same \c BaseTy and \c BaseDecl as

include/swift/Sema/IDETypeChecking.h

@@ -318,9 +318,9 @@ namespace swift {
   bool completionContextUsesConcurrencyFeatures(const DeclContext *dc);
 
   /// Determine the isolation of a particular closure.
-  ClosureActorIsolation determineClosureActorIsolation(
+  ActorIsolation determineClosureActorIsolation(
       AbstractClosureExpr *closure, llvm::function_ref<Type(Expr *)> getType,
-      llvm::function_ref<ClosureActorIsolation(AbstractClosureExpr *)>
+      llvm::function_ref<ActorIsolation(AbstractClosureExpr *)>
           getClosureActorIsolation);
 
   /// If the capture list shadows any declarations using shorthand syntax, i.e.

lib/AST/ASTDumper.cpp

@@ -2688,15 +2688,17 @@ class PrintExpr : public ExprVisitor<PrintExpr, void, StringRef>,
     printField(E->getRawDiscriminator(), "discriminator", DiscriminatorColor);
 
     switch (auto isolation = E->getActorIsolation()) {
-    case ClosureActorIsolation::Nonisolated:
+    case ActorIsolation::Unspecified:
+    case ActorIsolation::Nonisolated:
       break;
 
-    case ClosureActorIsolation::ActorInstance:
+    case ActorIsolation::ActorInstance:
       printFieldQuoted(isolation.getActorInstance()->printRef(),
                        "actor_isolated", CapturesColor);
       break;
 
-    case ClosureActorIsolation::GlobalActor:
+    case ActorIsolation::GlobalActor:
+    case ActorIsolation::GlobalActorUnsafe:
       printFieldQuoted(isolation.getGlobalActor().getString(),
                        "global_actor_isolated", CapturesColor);
       break;

lib/AST/Decl.cpp

@@ -10306,11 +10306,13 @@ bool VarDecl::isSelfParamCaptureIsolated() const {
 
     if (auto closure = dyn_cast<AbstractClosureExpr>(dc)) {
       switch (auto isolation = closure->getActorIsolation()) {
-      case ClosureActorIsolation::Nonisolated:
-      case ClosureActorIsolation::GlobalActor:
+      case ActorIsolation::Unspecified:
+      case ActorIsolation::Nonisolated:
+      case ActorIsolation::GlobalActor:
+      case ActorIsolation::GlobalActorUnsafe:
         return false;
 
-      case ClosureActorIsolation::ActorInstance:
+      case ActorIsolation::ActorInstance:
         auto isolatedVar = isolation.getActorInstance();
         return isolatedVar->isSelfParameter() ||
             isolatedVar-isSelfParamCapture();
@@ -10333,7 +10335,7 @@ ActorIsolation swift::getActorIsolation(ValueDecl *value) {
 
 ActorIsolation swift::getActorIsolationOfContext(
     DeclContext *dc,
-    llvm::function_ref<ClosureActorIsolation(AbstractClosureExpr *)>
+    llvm::function_ref<ActorIsolation(AbstractClosureExpr *)>
         getClosureActorIsolation) {
   auto dcToUse = dc;
   // Defer bodies share actor isolation of their enclosing context.
@@ -10349,7 +10351,7 @@ ActorIsolation swift::getActorIsolationOfContext(
     return getActorIsolation(var);
 
   if (auto *closure = dyn_cast<AbstractClosureExpr>(dcToUse)) {
-    return getClosureActorIsolation(closure).getActorIsolation();
+    return getClosureActorIsolation(closure);
   }
 
   if (auto *tld = dyn_cast<TopLevelCodeDecl>(dcToUse)) {
@@ -10597,6 +10599,33 @@ void swift::simple_display(llvm::raw_ostream &out, AnyFunctionRef fn) {
     out << "closure";
 }
 
+ActorIsolation::ActorIsolation(Kind kind, NominalTypeDecl *actor,
+                               unsigned parameterIndex)
+    : actorInstance(actor), kind(kind), 
+      isolatedByPreconcurrency(false),
+      parameterIndex(parameterIndex) { }
+
+ActorIsolation::ActorIsolation(Kind kind, VarDecl *capturedActor)
+    : actorInstance(capturedActor), kind(kind),
+      isolatedByPreconcurrency(false), 
+      parameterIndex(0) { }
+
+NominalTypeDecl *ActorIsolation::getActor() const {
+  assert(getKind() == ActorInstance);
+
+  if (auto *instance = actorInstance.dyn_cast<VarDecl *>()) {
+    return instance->getTypeInContext()
+        ->getReferenceStorageReferent()->getAnyActor();
+  }
+
+  return actorInstance.get<NominalTypeDecl *>();
+}
+
+VarDecl *ActorIsolation::getActorInstance() const {
+  assert(getKind() == ActorInstance);
+  return actorInstance.dyn_cast<VarDecl *>();
+}
+
 bool ActorIsolation::isMainActor() const {
   if (isGlobalActor()) {
     if (auto *nominal = getGlobalActor()->getAnyNominal())