[llvm] [WIP][SLP] SLP's copyable elements based upon Main/Alt operations. (PR #124242)

[Alexey Bataev via llvm-commits]

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@@ -4296,6 +4535,10 @@ class BoUpSLP {
     /// ScheduleData structures are recycled.
     DenseMap<Instruction *, ScheduleData *> ScheduleDataMap;
 
+    /// Attaches ScheduleData to Instruction with the leading key.
+    DenseMap<Value *, SmallDenseMap<Value *, ScheduleData *>>
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alexey-bataev wrote:

1. Not sure this solution will allow to solve all the problems.
2. Better to avoid adding new storages with the same logic as the existing one (ScheduleDataMap in your case). Better to extend the existing with the new functionality to avoid complex handling

https://github.com/llvm/llvm-project/pull/124242