[BillVan1945]

Summary

cif_v1 and cif_v1_export assume each sample has at least one CIF firing during frame processing. If a sample produces no firings while an earlier sample in the batch does, the code can access an invalid index and crash. Very short audio segments can trigger this case.

The guard added in #3028 handles batches where no sample fires. This fix covers mixed batches by skipping zero-fire samples when resetting frame boundaries.

Type of change

• Bug fix

Validation

python -m pytest -q tests/test_cif_mixed_zero_fires.py

• Before: 45 subcase errors. After: 6 tests and 98 subtests pass, including isolated CIF ONNX export and ONNX Runtime checks, with no skips.
• Real audio: short, nonempty segments produce CIF counts [1, 0]. With a fixed seed, three independent GPU runs per version fail before the fix and pass afterward.
• An additional 200 normal-input comparisons retain bitwise-identical CIF outputs.
• python -m compileall funasr examples tests and git diff --check pass.

User impact

Mixed batches containing trailing zero-fire samples complete CIF aggregation instead of crashing.