[region-isolation] Change SILIsolationInfo to only traffic in ActorIsolation instead of that or nominal type decls.

This should be NFC since the only case where I used this was with self... and I
found another way of doing that using the API I added in the previous commit.

Author: gottesmm

include/swift/SILOptimizer/Analysis/RegionAnalysis.h

@@ -162,7 +162,7 @@ class regionanalysisimpl::TrackableValueState {
   }
 
   ActorIsolation getActorIsolation() const {
-    return regionInfo.getActorIsolation().value();
+    return regionInfo.getActorIsolation();
   }
 
   void mergeIsolationRegionInfo(SILIsolationInfo newRegionInfo) {

include/swift/SILOptimizer/Utils/PartitionUtils.h

@@ -110,20 +110,19 @@ class SILIsolationInfo {
   // clang-format off
   std::variant<
     // Used for actor isolated when we have ActorIsolation info from the AST.
-    std::optional<ActorIsolation>,
-    // Used for actor isolation when we infer the actor at the SIL level.
-    NominalTypeDecl *,
+    ActorIsolation,
     // The task isolated parameter when we find a task isolated value.
     SILValue
   > data;
   // clang-format on
 
-  SILIsolationInfo(Kind kind, std::optional<ActorIsolation> actorIsolation)
-      : kind(kind), data(actorIsolation) {}
-  SILIsolationInfo(Kind kind, NominalTypeDecl *decl) : kind(kind), data(decl) {}
+  SILIsolationInfo(ActorIsolation actorIsolation)
+      : kind(Actor), data(actorIsolation) {}
 
   SILIsolationInfo(Kind kind, SILValue value) : kind(kind), data(value) {}
 
+  SILIsolationInfo(Kind kind) : kind(kind), data() {}
+
 public:
   SILIsolationInfo() : kind(Kind::Unknown), data() {}
 
@@ -146,18 +145,11 @@ class SILIsolationInfo {
 
   void printForDiagnostics(llvm::raw_ostream &os) const;
 
-  std::optional<ActorIsolation> getActorIsolation() const {
+  ActorIsolation getActorIsolation() const {
     assert(kind == Actor);
-    assert(std::holds_alternative<std::optional<ActorIsolation>>(data) &&
+    assert(std::holds_alternative<ActorIsolation>(data) &&
            "Doesn't have an actor isolation?!");
-    return std::get<std::optional<ActorIsolation>>(data);
-  }
-
-  NominalTypeDecl *getActorInstance() const {
-    assert(kind == Actor);
-    assert(std::holds_alternative<NominalTypeDecl *>(data) &&
-           "Doesn't have an actor instance?!");
-    return std::get<NominalTypeDecl *>(data);
+    return std::get<ActorIsolation>(data);
   }
 
   SILValue getTaskIsolatedValue() const {
@@ -167,45 +159,31 @@ class SILIsolationInfo {
     return std::get<SILValue>(data);
   }
 
-  bool hasActorIsolation() const {
-    return kind == Actor &&
-           std::holds_alternative<std::optional<ActorIsolation>>(data);
-  }
-
-  bool hasActorInstance() const {
-    return kind == Actor && std::holds_alternative<NominalTypeDecl *>(data);
-  }
+  bool hasActorIsolation() const { return kind == Actor; }
 
   bool hasTaskIsolatedValue() const {
     return kind == Task && std::holds_alternative<SILValue>(data);
   }
 
-  /// If we actually have an actor decl, return that. Otherwise, see if we have
-  /// an actor isolation if we can find one in there. Returns nullptr if we
-  /// fail.
-  NominalTypeDecl *tryInferActorDecl() const;
-
   [[nodiscard]] SILIsolationInfo merge(SILIsolationInfo other) const;
 
   SILIsolationInfo withActorIsolated(ActorIsolation isolation) {
     return SILIsolationInfo::getActorIsolated(isolation);
   }
 
-  static SILIsolationInfo getDisconnected() { return {Kind::Disconnected, {}}; }
+  static SILIsolationInfo getDisconnected() { return {Kind::Disconnected}; }
 
   static SILIsolationInfo getActorIsolated(ActorIsolation actorIsolation) {
-    return {Kind::Actor, actorIsolation};
+    return {actorIsolation};
   }
 
-  /// Sometimes we may have something that is actor isolated or that comes from
-  /// a type. First try getActorIsolation and otherwise, just use the type.
-  static SILIsolationInfo getActorIsolated(NominalTypeDecl *nomDecl) {
-    auto actorIsolation = swift::getActorIsolation(nomDecl);
-    if (actorIsolation.isActorIsolated())
-      return getActorIsolated(actorIsolation);
-    if (nomDecl->isActor())
-      return {Kind::Actor, nomDecl};
-    return SILIsolationInfo();
+  static SILIsolationInfo getActorIsolated(NominalTypeDecl *typeDecl) {
+    if (typeDecl->isActor())
+      return {ActorIsolation::forActorInstanceSelf(typeDecl)};
+    auto isolation = swift::getActorIsolation(typeDecl);
+    if (isolation.isGlobalActor())
+      return {isolation};
+    return {};
   }
 
   static SILIsolationInfo getGlobalActorIsolated(Type globalActorType) {

lib/SILOptimizer/Analysis/RegionAnalysis.cpp

@@ -624,11 +624,7 @@ void SILIsolationInfo::printForDiagnostics(llvm::raw_ostream &os) const {
     os << "disconnected";
     return;
   case Actor:
-    if (hasActorIsolation() && getActorIsolation()) {
-      getActorIsolation()->printForDiagnostics(os);
-    } else {
-      os << "actor-isolated";
-    }
+    getActorIsolation().printForDiagnostics(os);
     return;
   case Task:
     os << "task-isolated";

lib/SILOptimizer/Utils/PartitionUtils.cpp

@@ -93,10 +93,7 @@ SILIsolationInfo SILIsolationInfo::get(SILFunctionArgument *arg) {
     if (auto functionIsolation = arg->getFunction()->getActorIsolation()) {
       if (functionIsolation.isActorIsolated()) {
         if (auto *nomDecl = self->getType().getNominalOrBoundGenericNominal()) {
-          if (auto isolationInfo =
-                  SILIsolationInfo::getActorIsolated(nomDecl)) {
-            return isolationInfo;
-          }
+          return SILIsolationInfo::getActorIsolated(nomDecl);
         }
       }
     }
@@ -135,23 +132,6 @@ void SILIsolationInfo::print(llvm::raw_ostream &os) const {
   }
 }
 
-NominalTypeDecl *SILIsolationInfo::tryInferActorDecl() const {
-  if (hasActorIsolation()) {
-    auto actorIsolation = getActorIsolation();
-    if (auto *actor = actorIsolation->getActorOrNullPtr()) {
-      return actor;
-    }
-    return nullptr;
-  }
-
-  if (hasActorInstance()) {
-    auto actorDecl = getActorInstance();
-    return actorDecl;
-  }
-
-  return nullptr;
-}
-
 SILIsolationInfo SILIsolationInfo::merge(SILIsolationInfo other) const {
   // If we are greater than the other kind, then we are further along the
   // lattice. We ignore the change.
@@ -179,21 +159,9 @@ bool SILIsolationInfo::operator==(const SILIsolationInfo &other) const {
     return getTaskIsolatedValue() == other.getTaskIsolatedValue();
   case Actor:
     // First try to use actor isolation if we have them.
-    if (hasActorIsolation() && other.hasActorIsolation()) {
-      auto lhsIsolation = getActorIsolation();
-      auto rhsIsolation = other.getActorIsolation();
-      if (lhsIsolation && rhsIsolation)
-        return *lhsIsolation == *rhsIsolation;
-    }
-
-    // Otherwise, try to use the inferred actor decl.
-    auto *lhsDecl = tryInferActorDecl();
-    auto *rhsDecl = other.tryInferActorDecl();
-    if (lhsDecl && rhsDecl)
-      return lhsDecl == rhsDecl;
-
-    // Otherwise, false, they are not equal.
-    return false;
+    auto lhsIsolation = getActorIsolation();
+    auto rhsIsolation = other.getActorIsolation();
+    return lhsIsolation == rhsIsolation;
   }
 }
 
@@ -207,22 +175,8 @@ void SILIsolationInfo::Profile(llvm::FoldingSetNodeID &id) const {
     id.AddPointer(getTaskIsolatedValue());
     return;
   case Actor:
-    // We profile in integer cases here so that we can always distinguish in
-    // between the various cases and the non-case. Just being paranoid.
-    if (hasActorIsolation()) {
-      if (auto isolation = getActorIsolation()) {
-        id.AddInteger(1);
-        return isolation->Profile(id);
-      }
-    }
-
-    if (hasActorInstance()) {
-      id.AddInteger(2);
-      return id.AddPointer(getActorInstance());
-    }
-
-    id.AddInteger(3);
-    break;
+    getActorIsolation().Profile(id);
+    return;
   }
 }