[llvm] [CodeGen] Split wide active lane mask into smaller masks if preferred (PR #202909)

[Kerry McLaughlin via llvm-commits]

kmclaughlin-arm wrote:

> Yeah we don't use the active.lane.mask tail folding style on RISC-V so don't worry about the codegen on our end. I think early exits with stores might generate an AML on RISC-V but I don't think we unroll those currently?

Thanks for confirming. It looks like loops with early exits are prevented from unrolling, even if an interleave count is forced.

https://github.com/llvm/llvm-project/pull/202909