[llvm] [PowerPC] cost modeling for length type VP intrinsic load/store (PR #168938)

[via llvm-commits]

RolandF77 wrote:

> Can you add a test to LV which enable EVL for PPC and check that is doing something senisble with data-with-evl tail-folding style?

LV will not currently tail fold for fixed length vectors (which is all PPC has), so a test will not show anything right now. I would like to add support for tail folding fixed length vectors, and this PR is a step toward that.

https://github.com/llvm/llvm-project/pull/168938