fix: apply logit bias before greedy sampling#507
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HenryNdubuaku merged 4 commits intomainfrom Mar 9, 2026
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Signed-off-by: Noah Cylich <[email protected]>
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Pull request overview
Fixes sampling correctness by ensuring logit bias is applied before the greedy (temperature=0) early-return path, so greedy decoding selects the argmax of biased logits rather than raw logits.
Changes:
- Apply logit bias before the greedy early-return in
cactus_sample_f32andcactus_sample_f16. - Replace manual copy loops with
std::memcpyand manual argmax loops withstd::max_element. - In FP16 sampling, ensure temperature scaling operates on
filtered_logits(so bias is preserved through scaling).
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Moves the empty-vocab guard to the top of cactus_sample_f32 and cactus_sample_f16 so it covers all paths (not just greedy), preventing UB from std::max_element on empty vectors. Signed-off-by: Noah Cylich <[email protected]>
Signed-off-by: Noah Cylich <[email protected]>
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Pull request overview
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assert(n <= 8) is compiled out in release builds, leaving the fixed-size float c[8] buffer unprotected. Replace with an early return. Signed-off-by: Noah Cylich <[email protected]>
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Summary
cactus_sample_f32andcactus_sample_f16std::max_elementand manual copy loops withstd::memcpy