[llvm] [SLP]Remove emission of vector_insert/vector_extract intrinsics (PR #148007)

[Simon Pilgrim via llvm-commits]

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@@ -16864,10 +16877,13 @@ class BoUpSLP::ShuffleInstructionBuilder final : public BaseShuffleAnalysis {
                                          V, SimplifyQuery(*R.DL));
                                    }));
           unsigned InsertionIndex = Idx * getNumElements(ScalarTy);
+          Type *OrigScalarTy = ScalarTy;
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RKSimon wrote:

add a comment why this is necessary

https://github.com/llvm/llvm-project/pull/148007