[llvm] [SLP] Check for extracts, being replaced by original scalars, for user nodes (PR #149572)

[Craig Topper via llvm-commits]

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@@ -12102,6 +12213,27 @@ void BoUpSLP::transformNodes() {
       ArrayRef<Value *> VL = E.Scalars;
       const unsigned Sz = getVectorElementSize(VL.front());
       unsigned MinVF = getMinVF(2 * Sz);
+      const EdgeInfo &EI = E.UserTreeIndex;
+      // Try to vectorized postponed scalars, if external uses are vectorized.
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topperc wrote:

```suggestion
      // Try to vectorize postponed scalars, if external uses are vectorized.
```

https://github.com/llvm/llvm-project/pull/149572