[llvm] [InstCombine] Fold "extract (select (cond, insert(agg, elem), FV))" (PR #115969)

[Yingwei Zheng via llvm-commits]

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

LG. Please wait for additional approval from other reviewers.

We may generalize to use simplifyInstruction for other instructions in the future.


https://github.com/llvm/llvm-project/pull/115969