[NFC][ADT] Remove unnecessary struct ilist_node_traits

[prehistoric-penguin]

Summary

Remove unnecessary struct ilist_node_traits according to todo

[dexonsmith]

I don’t have easy access to git-grep right now. Can you confirm that there are no other uses of this left over? (E.g., a forward declaration and specialization somewhere?)

[prehistoric-penguin]

In D129723#3651869, @dexonsmith wrote:

I don’t have easy access to git-grep right now. Can you confirm that there are no other uses of this left over? (E.g., a forward declaration and specialization somewhere?)

I have confirmed that there is no other reference except the one I removed, thanks!

[RKSimon]

Please can you improve the subject line / description - at least mention what struct you are removing / motivation.

[prehistoric-penguin]

[NFC][ADT] Remove unnecessary struct ilist_node_traits

[prehistoric-penguin]

In D129723#3659090, @RKSimon wrote:

Please can you improve the subject line / description - at least mention what struct you are removing / motivation.

I have updated it, thanks!

[RKSimon]

subject line / description still needs updating

[prehistoric-penguin]

Thanks, the subject line, and description are updated.

[RKSimon]

LGTM

llvm/include/llvm/ADT/ilist.h

template <typename NodeTy> struct ilist_callback_traits {
   /// in this same list.
   template <class Iterator>
   void transferNodesFromList(ilist_callback_traits &OldList, Iterator /*first*/,
                              Iterator /*last*/) {
     (void)OldList;
   }
 };
 
-/// A fragment for template traits for intrusive list that provides default
-/// node related operations.
-///
-/// TODO: Remove this layer of indirection.  It's not necessary.
-template <typename NodeTy>
-struct ilist_node_traits : ilist_alloc_traits<NodeTy>,
-                           ilist_callback_traits<NodeTy> {};
-
 /// Template traits for intrusive list.
 ///
 /// Customize callbacks and allocation semantics.
 template <typename NodeTy>
-struct ilist_traits : public ilist_node_traits<NodeTy> {};
+struct ilist_traits : ilist_alloc_traits<NodeTy>,
+                      ilist_callback_traits<NodeTy> {};
 
 /// Const traits should never be instantiated.
 template <typename Ty> struct ilist_traits<const Ty> {};
 
 namespace ilist_detail {
 
 template <class T> T &make();