[llvm] [IR] Implementation and lowering of bitinsert and bitextract (PR #200605)

[Antonio Frighetto via llvm-commits]

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antoniofrighetto wrote:

It would be better to regenerate check-lines with ./llvm/utils/update_llc_test_checks.py, same below for the GlobalISel test.

https://github.com/llvm/llvm-project/pull/200605