[llvm] [NVPTX] Lower allocas to the local address space (PR #204346)

[Drew Kersnar via llvm-commits]

dakersnar wrote:

>  I'm a little worried this will have a performance S-curve

Alex, can you expand on what specifically about this you think risks an scurve? Is it more of a general worry that more addrspacecasts in the IR might cause unexpected churn somewhere else in the pipeline?

https://github.com/llvm/llvm-project/pull/204346