[llvm] [SimplifyCFG] Extend SimplifyCFG to lower s/ucmp + 3-arm switch (PR #222786)

[Joe Isaacs via llvm-commits]

joseph-isaacs wrote:

I miss understood the intent of the CGP pass and thought it was preferable to use for cost model gated program. I will update the PR to use the CGP pass


https://github.com/llvm/llvm-project/pull/222786