apriel2 modeling bug

[oleksost]

✨ Description

Bugs in the recurrent step path used in generation.

This makes GSM8k generations actually sensical.

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[tscholak]

important fixes!

[tscholak]

great catch!

[tscholak]

this is the torch implementation, right? under normal circumstances we wouldn't hit this code path because we're using the FLA kernel, no?

[oleksost]

The torch fallback is torch_chunk_gated_delta_rule. The _recurrent_gated_delta_rule is used at decoding time in recurrent mode (i.e. after prefill)

[tscholak]

there's an FLA kernel for chunk_gated_delta_rule that we can use. I think you saw that too now. thanks for approving!

[tscholak]

when I looked at these changes, I realized that it doesn't make sense to have a torch fallback. I decided to just remove that code. The outcome is #451

[tscholak]

good stuff