From 00e401b33faf769df288ccb32f7feca684b2df6e Mon Sep 17 00:00:00 2001
From: Hamish Knight <hamish_knight@apple.com>
Date: Sun, 2 Nov 2025 21:46:21 +0000
Subject: [PATCH] [Sema] NFC: Remove
 `GetDistributedMethodWitnessedProtocolRequirements`

This has been unused for over a year now, let's just remove it.
---
 include/swift/AST/Decl.h                    |  9 ---------
 include/swift/AST/TypeCheckRequests.h       | 21 ---------------------
 include/swift/AST/TypeCheckerTypeIDZone.def |  3 ---
 lib/AST/DistributedDecl.cpp                 | 15 ---------------
 lib/Sema/TypeCheckDistributed.cpp           | 18 ------------------
 5 files changed, 66 deletions(-)

diff --git a/include/swift/AST/Decl.h b/include/swift/AST/Decl.h
index e21becfbe2039..490903e444e1c 100644
--- a/include/swift/AST/Decl.h
+++ b/include/swift/AST/Decl.h
@@ -8118,15 +8118,6 @@ class AbstractFunctionDecl : public GenericContext, public ValueDecl {
            getSILSynthesizeKind() == SILSynthesizeKind::DistributedActorFactory;
   }
 
-  /// Return a vector of distributed requirements that this distributed method
-  /// is implementing.
-  ///
-  /// If the method is witness to multiple requirements this is incorrect and
-  /// should be diagnosed during type-checking as it may make remoteCalls
-  /// ambiguous.
-  llvm::ArrayRef<ValueDecl *>
-  getDistributedMethodWitnessedProtocolRequirements() const;
-
   /// Determines whether this function is a 'remoteCall' function,
   /// which is used as ad-hoc protocol requirement by the
   /// 'DistributedActorSystem' protocol.
diff --git a/include/swift/AST/TypeCheckRequests.h b/include/swift/AST/TypeCheckRequests.h
index 928484825f3b1..e95e90810bd09 100644
--- a/include/swift/AST/TypeCheckRequests.h
+++ b/include/swift/AST/TypeCheckRequests.h
@@ -1598,27 +1598,6 @@ class GetDistributedActorConcreteArgumentDecodingMethodRequest :
   bool isCached() const { return true; }
 };
 
-/// Find out if a distributed method is implementing a distributed protocol
-/// requirement.
-class GetDistributedMethodWitnessedProtocolRequirements :
-    public SimpleRequest<GetDistributedMethodWitnessedProtocolRequirements,
-                         llvm::ArrayRef<ValueDecl *> (AbstractFunctionDecl *),
-                         RequestFlags::Cached> {
-public:
-  using SimpleRequest::SimpleRequest;
-
-private:
-  friend SimpleRequest;
-
-  llvm::ArrayRef<ValueDecl *> evaluate(
-      Evaluator &evaluator,
-      AbstractFunctionDecl *nominal) const;
-
-public:
-  // Caching
-  bool isCached() const { return true; }
-};
-
 /// Retrieve the static "shared" property within a global actor that provides
 /// the actor instance representing the global actor.
 ///
diff --git a/include/swift/AST/TypeCheckerTypeIDZone.def b/include/swift/AST/TypeCheckerTypeIDZone.def
index 3e6d7dbc18baf..500bf2145266a 100644
--- a/include/swift/AST/TypeCheckerTypeIDZone.def
+++ b/include/swift/AST/TypeCheckerTypeIDZone.def
@@ -160,9 +160,6 @@ SWIFT_REQUEST(TypeChecker, GetDistributedActorSystemPropertyRequest,
 SWIFT_REQUEST(TypeChecker, GetDistributedRemoteCallTargetInitFunctionRequest,
               ConstructorDecl *(NominalTypeDecl *),
               Cached, NoLocationInfo)
-SWIFT_REQUEST(TypeChecker, GetDistributedMethodWitnessedProtocolRequirements,
-              ArrayRef<ValueDecl *> (AbstractFunctionDecl *),
-              Cached, NoLocationInfo)
 SWIFT_REQUEST(TypeChecker, GetDistributedRemoteCallArgumentInitFunctionRequest,
               ConstructorDecl *(NominalTypeDecl *),
               Cached, NoLocationInfo)
diff --git a/lib/AST/DistributedDecl.cpp b/lib/AST/DistributedDecl.cpp
index 3d9cf93799cc5..a3bfa0d58f2e2 100644
--- a/lib/AST/DistributedDecl.cpp
+++ b/lib/AST/DistributedDecl.cpp
@@ -453,21 +453,6 @@ bool swift::checkDistributedSerializationRequirementIsExactlyCodable(
       std::count(protocols.begin(), protocols.end(), decodable) == 1;
 }
 
-// TODO(distributed): probably can be removed?
-llvm::ArrayRef<ValueDecl *>
-AbstractFunctionDecl::getDistributedMethodWitnessedProtocolRequirements() const {
-  auto mutableThis = const_cast<AbstractFunctionDecl *>(this);
-
-  // Only a 'distributed' decl can witness 'distributed' protocol
-  if (!isDistributed()) {
-    return llvm::ArrayRef<ValueDecl *>();
-  }
-
-  return evaluateOrDefault(
-      getASTContext().evaluator,
-      GetDistributedMethodWitnessedProtocolRequirements(mutableThis), {});
-}
-
 /******************************************************************************/
 /********************* Ad-hoc protocol requirement checks *********************/
 /******************************************************************************/
diff --git a/lib/Sema/TypeCheckDistributed.cpp b/lib/Sema/TypeCheckDistributed.cpp
index 54ca3fd900676..be5ee394050a9 100644
--- a/lib/Sema/TypeCheckDistributed.cpp
+++ b/lib/Sema/TypeCheckDistributed.cpp
@@ -945,21 +945,3 @@ GetDistributedActorConcreteArgumentDecodingMethodRequest::evaluate(
   /// witness
   return nullptr;
 }
-
-llvm::ArrayRef<ValueDecl *>
-GetDistributedMethodWitnessedProtocolRequirements::evaluate(
-    Evaluator &evaluator,
-    AbstractFunctionDecl *afd) const {
-  // Only a 'distributed' decl can witness 'distributed' protocol
-  assert(afd->isDistributed());
-  auto &C = afd->getASTContext();
-
-  auto result = llvm::SmallVector<ValueDecl *, 1>();
-  for (auto witnessedRequirement : afd->getSatisfiedProtocolRequirements()) {
-    if (witnessedRequirement->isDistributed()) {
-      result.push_back(witnessedRequirement);
-    }
-  }
-
-  return C.AllocateCopy(result);
-}