Flow of Matmul changed since v0.4.31

[Rohanjames1997]

Hi!

I'd like to understand the flow of matmul in jax/openxla. I'm focusing on the choice made between eigen and ACL kernels.

When I used Jax v0.4.31, by printing out logs and traces, I found that this path in openxla was taken: path. Upon backtracing, it was found to take the path along EmitDotOperation()

Now, while using the main branch, matmul does not take this path. It instead takes the path along EmitFusionHostKernel()

This might be niche, but does anyone know when/why this change was made, and if there are flags that control the flow?

Thanks!

[Rohanjames1997]

Turns out to be due to this PR: openxla/xla#15830