[llvm] [SLP][NFC] Remove useless code of deleting ExtractElementInst (PR #106697)

[via llvm-commits]

tcwzxx wrote:

> removeInstructionsAndOperands works only for vectorized scalars. adjustExtracts handles extractelements, which are not vectorized, part of buildvector

The `extractelements` of `buildvector` are operators of vectorized scalars. `removeInstructionsAndOperands` should have already handled this correctly?"


https://github.com/llvm/llvm-project/pull/106697