[llvm] [InstSimplify] Simplify extractvalue (umul_with_overflow(x, 1)). (PR #157307)

[Nikita Popov via llvm-commits]

https://github.com/nikic approved this pull request.

LGTM. This has obvious generalizations, but not sure they're worth adding (given the more generic handling in InstCombine).

https://github.com/llvm/llvm-project/pull/157307