SIL: FunctionArgument.copyFlags needs a MutatingContext argument

SIL may only be modified through a MutatingContext. Otherwise analysis notifications may get lost.

Author: eeckstein

SwiftCompilerSources/Sources/Optimizer/FunctionPasses/ClosureSpecialization.swift

@@ -710,7 +710,7 @@ private extension SpecializationCloner {
       .forEach { _, arg in
         let clonedEntryBlockArgType = arg.type.getLoweredType(in: clonedFunction)
         let clonedEntryBlockArg = clonedEntryBlock.addFunctionArgument(type: clonedEntryBlockArgType, self.context)
-        clonedEntryBlockArg.copyFlags(from: arg as! FunctionArgument)
+        clonedEntryBlockArg.copyFlags(from: arg as! FunctionArgument, self.context)
       }
   }
 

SwiftCompilerSources/Sources/Optimizer/PassManager/Context.swift

@@ -656,6 +656,18 @@ extension Argument {
   }
 }
 
+extension FunctionArgument {
+  /// Copies the following flags from `arg`:
+  /// 1. noImplicitCopy
+  /// 2. lifetimeAnnotation
+  /// 3. closureCapture
+  /// 4. parameterPack
+  func copyFlags(from arg: FunctionArgument, _ context: some MutatingContext) {
+    context.notifyInstructionsChanged()
+    bridged.copyFlags(arg.bridged)
+  }
+}
+
 extension AllocRefInstBase {
   func setIsStackAllocatable(_ context: some MutatingContext) {
     context.notifyInstructionsChanged()

SwiftCompilerSources/Sources/SIL/Argument.swift

@@ -83,15 +83,6 @@ final public class FunctionArgument : Argument {
   public var resultDependence: LifetimeDependenceConvention? {
     parentFunction.argumentConventions[resultDependsOn: index]
   }
-
-  /// Copies the following flags from `arg`:
-  /// 1. noImplicitCopy
-  /// 2. lifetimeAnnotation
-  /// 3. closureCapture
-  /// 4. parameterPack
-  public func copyFlags(from arg: FunctionArgument) {
-    bridged.copyFlags(arg.bridged)
-  }
 }
 
 public struct Phi {