[llvm] [SimplifyCFG] Improve range reducing for switches (PR #67882)

[Yingwei Zheng via llvm-commits]

dtcxzyw wrote:

> But your PR seems to be a special case of handling sparse values? Is it possible to handle this type of issue like [rust-lang/rust#114106 (comment)](https://github.com/rust-lang/rust/issues/114106#issuecomment-1657131825) does.

I will try optimizing sparse switches with perfect hashing. Thank you!


https://github.com/llvm/llvm-project/pull/67882