Avoid inserting end_cow_mutation_addr in some common cases

Author: meg-gupta

SwiftCompilerSources/Sources/Optimizer/FunctionPasses/LifetimeDependenceScopeFixup.swift

@@ -176,6 +176,24 @@ private extension Type {
     }
     return false
   }
+
+  // Returns true if a type maybe Array/ArraySlice/ContiguousArray which are optimized COW types.
+  // The standard library introduces builtins begin_cow_mutation/end_cow_mutation for such types which are then used to optimize uniqueness checks.
+  func mayHaveOptimizedCOWType(in function: Function) -> Bool {
+    // Trivial types cannot be Array/ArraySlice/ContiguousArray.
+    if isTrivial(in: function) {
+      return false
+    }
+    // Builtin types do not contain Array/ArraySlice/ContiguousArray.
+    if isBuiltinType {
+      return false
+    }
+    // ~Copyable types cannot contain Array/ArraySlice/ContiguousArray.
+    if isMoveOnly {
+      return false
+    }
+    return true
+  }
 }
 
 /// Insert end_cow_mutation_addr for lifetime dependent values that maybe of type MutableSpan and depend on a mutable address.
@@ -203,7 +221,8 @@ private func createEndCOWMutationIfNeeded(lifetimeDep: LifetimeDependence, _ con
       return
   }
 
-  guard lifetimeDep.dependentValue.type.mayHaveMutableSpan(in: lifetimeDep.dependentValue.parentFunction, context) else {
+  guard lifetimeDep.dependentValue.type.mayHaveMutableSpan(in: lifetimeDep.dependentValue.parentFunction, context) &&
+    lifetimeDep.parentValue.type.mayHaveOptimizedCOWType(in: lifetimeDep.dependentValue.parentFunction) else {
     return
   }