liminfei-amd 62e025a4f3 Fix FP8 activation quantization for >2D activations in mixed_precision_ops (#14643) ...

mixed_precision_ops.Linear.forward only quantized activations that were 2D, or
3D (reshaped to 2D). Inputs with rank >= 4 (e.g. Anima's MLP activations, which
are not reshaped to 3D the way the attention path is) fell through the
`input_reshaped.ndim == 2` guard and reached scaled_mm as bf16, silently
dispatching a bf16 kernel instead of FP8. Since MLP is roughly half the compute,
the FP8 speedup was far below expectation.

Generalize the existing 3D->2D reshape to any rank >= 3 (flatten the leading
dims, keep the contraction dim) and reshape the output back to the original
leading dims. 2D and 3D inputs are handled exactly as before; only rank >= 4
inputs change (now quantized instead of skipped). This matches the rank-agnostic
handling already used by the training path (flatten(0, -2) / unflatten).

Fixes #14595.

2026-07-09 22:30:26 -04:00

70 KiB

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