[llvm] [AVR][NFC] Simplify branch relaxation tests (PR #131871)

[Patryk Wychowaniec via llvm-commits]

Patryk27 wrote:

Yes~no - they are separate, because they check this:

https://github.com/llvm/llvm-project/blob/1f967887018c63bddf5bf2860e0e6a3aa1e85840/llvm/lib/Target/AVR/AVRDevices.td#L63 (aka https://github.com/llvm/llvm-project/pull/118015)

Merging them into a single file would probably work, but it'd be tiiiny bit illegal, because the generated binary would technically be larger than 8 kB (I could imagine LLVM refusing to compile such code in the future, for instance).

https://github.com/llvm/llvm-project/pull/131871