[llvm] [VPlan] Introduce VPInstruction::InsertLastLane for start value of VPFirstOrderRecurrencePHIRecipe. (PR #171590)

[Luke Lau via llvm-commits]

https://github.com/lukel97 commented:

Makes sense to me, is it possible to write a test case that shows the CSE with multiple FORs?

https://github.com/llvm/llvm-project/pull/171590