[PATCH] D107344: [SLP]Do not emit extra shuffle for insertelements vectorization.

[Alexey Bataev via Phabricator via llvm-commits]

ABataev added a comment.

In D107344#2926172 <https://reviews.llvm.org/D107344#2926172>, @srj wrote:

> It's not entirely clear to me how the intended logic of this patch is supposed to work, but skipping the extra shufflevector when `Offset == 0` seems puzzling here; in this case, we are definitely producing a meaningfully different result in this case (essentially, inserting value of 100 at index 3). I'm not sure what the correct fix is here (still looking) but I think this should give you enough info to make progress. (If not, we should should revert this change pending a proper fix.)

Yes, you're right, need an extra check here for the `FirstInsert->getOperand(0)`, will fix it.


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https://reviews.llvm.org/D107344