[llvm] Add late optimization pass for riscv (PR #117060)

[Craig Topper via llvm-commits]

topperc wrote:

> I can't find any target which implements this "trivially evaluated cond branch -> unconditional branch" in analyzeBranch, but I also can't find any reason why you can't do this if AllowModify=true.

Are you suggesting analyzeBranch should look through copies to figure this out?

https://github.com/llvm/llvm-project/pull/117060