[llvm] [SLP][NFC] Redesign schedule bundle, separate from schedule data, NFC (PR #131625)

[Gaëtan Bossu via llvm-commits]

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@@ -4011,26 +4014,55 @@ class BoUpSLP {
   /// List of hashes of vector of loads, which are known to be non vectorizable.
   DenseSet<size_t> ListOfKnonwnNonVectorizableLoads;
 
+  class ScheduleEntity {
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gbossu wrote:

Could you maybe add a top level comment? It's not clear to me what a `ScheduleEntity` represents. Is it just a wrapper around some `llvm::instruction` to store extra information needed for scheduling?

I would suggest to give a bit more details about the two `ScheduleData` and `ScheduleBundle` variants. That might make it move obvious why the `ScheduleEntity` abstraction makes sense.

https://github.com/llvm/llvm-project/pull/131625