[llvm] Refactored llvm::UpgradeIntrinsicCall() function in lib/IR/AutoUpgrade.cpp with lookup table based on #30382 (PR #128611)

[Nikita Popov via llvm-commits]

https://github.com/nikic requested changes to this pull request.

This change makes very little sense. You're creating the table for every single upgrade and then walking over the table. It makes the code slower and does not make it clearer.

https://github.com/llvm/llvm-project/pull/128611