[llvm] [AIX][TLS] Produce a faster local-exec access sequence for the "aix-small-tls" global variable attribute (PR #83053)

[Felix via llvm-commits]

https://github.com/orcguru commented:

Does it make sense to turn the function level attribute HasAIXSmallLocalExecTLS into variable attributes for example by `addAttribute` inside `LowerGlobalTLSAddressAIX`, and then we only need to check variable attribute for the peepholes?

For any TLS LE variable accessed by more than one functions, and if one of them HasAIXSmallLocalExecTLS, then that variable should better have the "aix-small-tls" attribute?

https://github.com/llvm/llvm-project/pull/83053