[Mlir-commits] [mlir] [mlir][test] Make SME e2e tests require an emulator (PR #86489)

[Andrzej Warzyński]

banach-space wrote:

> How do you query the HW support during the lit config phase though?

The information would have come from the user. Here's what I'm proposing:
1. Introduce new CMake flag: `LLVM_TARGET_ARCH_FEATURES`. Propagate as `config.target_features` in LIT.
2. Require one of the two: 
* `-DMLIR_RUN_ARM_SME_TESTS -DARM_EMULATOR_EXECUTABLE=<>` (run via emulator), or 
* `-DMLIR_RUN_ARM_SME_TESTS -DLLVM_TARGET_ARCH_FEATURES="sme"` (run on hardware once available).

Setting `-DLLVM_TARGET_ARCH_FEATURES="sme"` on hardware that doesn't support SME would be a user error.

Not ideal and not that automatic, but that's the best I have ATM. I don't know how to reliably query hardware, hence I am hesitant to explore that. Suggestions are very welcome though!

https://github.com/llvm/llvm-project/pull/86489