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

[Dinar Temirbulatov via llvm-commits]

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@@ -3298,6 +3462,7 @@ class BoUpSLP {
                          ///< complex node like select/cmp to minmax, mul/add to
                          ///< fma, etc. Must be used for the following nodes in
                          ///< the pattern, not the very first one.
+      CopyableVectorize, ///< The node for copyable elements.
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dtemirbulatov wrote:

My motivation was to simplifiy the solution, I will check the other way, thanks.

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