[clang] [llvm] [NVPTX] Change the alloca address space in NVPTXLowerAlloca (PR #154814)

[Eli Friedman via llvm-commits]

https://github.com/efriedma-quic commented:

Modifying the datalayout feels really strange, and I'm sort of worried it'll have unintended consequences, especially if there's only one target doing it.  

Maybe you can just skip modifying the datalayout?  The passes that run after createNVPTXLowerAllocaPass realistically shouldn't be creating allocas, and if one does slip through somehow you can fix it up in SelectionDAG.

https://github.com/llvm/llvm-project/pull/154814