[llvm] [CodeGen][AArch64] Set min jump table entries to 13 for AArch64 targets (PR #71166)

[David Sherwood via llvm-commits]

david-arm wrote:

> I think it's actually noise, don't think I see improvements on the V2. Perhaps that's still okay because it is shows improvements on the V1. But now I am actually wondering if the V1 improvement is an actual improvement, or do we get lucky with secondary effects such as different function/loop/block alignments?

What I also saw was a gradual improvement in performance as you increased the threshold for creating jump tables. For example, I'd get consistently better results with a minimum threshold of 6, then even better with 10, then the best around 13. When I saw that trend of improving performance with higher threshold it made me think this wasn't just luck or coincidence, and that there is a genuine correlation.

https://github.com/llvm/llvm-project/pull/71166