[Mlir-commits] [mlir] [mlir][spirv] Update `argmax-kernel` lit test for `convert-to-spirv`. NFC. (PR #106586)

[Jakub Kuderski]

kuhar wrote:

> This seems pretty large as a unit-test for conversion, can you elaborate on this test?

This is effectively an integration tests for the convert-to-spirv pass. Unit tests are placed in each dialect conversion pass. Here want to make sure that a small complete kernel can be converted like we'd expect, including the interaction between dialects, control flow, type legalization, memory operations, etc. Historically, we saw failures in some combination of these like indices not being properly legalized.

We picked argmax because it's a very simple example of code that does something that's not completely contrived: it scans the input buffer, loops over the content, and uses a spirv op as an 'intrinsic' for subgroup operations. We do not plan to add more of similar tests unless we can demonstrate that they fill some actual gaps in the coverage. We had a short-lived e2e tests for argmax, but that was a mistake -- this is better suited for a LIT test IMO.

https://github.com/llvm/llvm-project/pull/106586