[llvm-branch-commits] [llvm] [SelectionDAG] Fold EXTRACT_SUBVECTOR(EXTRACT_SUBVECTOR(X, C1), C0) with nonzero indices (PR #200935)

[Krzysztof Drewniak via llvm-branch-commits]

krzysz00 wrote:

@RKSimon I can't for the life of me find an end-to-end test that actually triggers off of this one. Would you accept a pass-specific test here?

Also, it's a patch stack because, at the end of the stack, there's a regression test for a compiler hang. I could probably rebase these all off of main and make the regression test its own commit, though.

... Ok, yeah, I'll do that.

https://github.com/llvm/llvm-project/pull/200935