[llvm] [BasicTTIImpl] Don't unroll loops with vector insts (PR #147982)

[Nikita Popov via llvm-commits]

nikic wrote:

As a counter-point, see https://github.com/llvm/llvm-project/pull/147420, which wants to limit this only to auto-vectorized loops.

(Doesn't the vectorizer already emit metadata to disable unrolling?)

https://github.com/llvm/llvm-project/pull/147982