[llvm] [LV] Vectorize early exit loops with multiple exits. (PR #174864)

[Florian Hahn via llvm-commits]

fhahn wrote:

Updated after landing legality checks separately. I also added https://github.com/llvm/llvm-test-suite/pull/325 to add dedicated runtime tests for multiple early exits to llvm-test-suite

https://github.com/llvm/llvm-project/pull/174864