CB1+CB2 swapped labels D→A+B; this swaps the kernels to match.
aux_heads.cu — 4-output structure:
- Forward: 12 outputs per snapshot = 4 per direction × N_HORIZONS
(prof_long_logit, size_long_pred, prof_short_logit, size_short_pred,
each [N_HORIZONS]). Linear projections; sigmoid applied in BCE kernel.
- Backward: accepts 4 grad_y inputs, produces 8 grad_W + 8 grad_b +
grad_h_aux. Cooperative h_aux staging in shmem once per block.
- 8 weight matrices total, Xavier × 0.1 init under scoped_init_seed.
aux_loss.cu — 2 kernels:
- aux_bce_loss_fwd_bwd: class-weighted BCE+sigmoid fused. pos_weight in
shared mem; scales positive-class gradient. NaN-mask y_true.
- aux_huber_masked_fwd_bwd: Huber w/ NaN-mask. CB1's y_size=NaN at
y_prof=0 provides the conditional-Huber semantics naturally — no
separate mask buffer needed.
aux_heads.rs:
- AuxHeads + AuxHeadsWeights: 8 buffer fields (4 W + 4 b)
- AuxBceLoss + AuxMaskedHuberLoss wrappers replace AuxHuberLoss
- POS_WEIGHT_MIN/MAX = [1.0, 50.0] clamps per E3
- aux_heads_fwd_gpu/aux_heads_bwd_gpu/aux_bce_loss_gpu/aux_huber_masked_loss_gpu
perception.rs (minimal compile-keeping signature updates only):
- Renamed/added buffers: 4 prediction (prof/size × long/short),
4 label staging, 4 grad_y per-K, 8 head grad scratches, 8 head Adam
optimizers, 2 pos_weight buffers (device + staging)
- HOLDING PATTERN: bwd zeroes the 4 grad_y_per_K buffers each step so
the head Adam updates are no-ops on grad=0 (no aux gradient signal
this commit). CB5 wires the actual aux_bce + aux_huber_masked calls.
- BCE direction signal + dir_acc readouts updated to use the new
prof_long/prof_short prediction buffers (so existing perception_overfit
aux test still passes).
7 GPU oracle tests on RTX 3050 sm_86, all pass in 2.43s:
- fwd_matches_naive_reference, bwd_finite_diff_matches_bias_sample,
aux_bce_loss_matches_naive_reference, aux_bce_pos_weight_scales_positive_gradient
(verified: pos_weight=10 → 10× gradient ratio within 1e-4),
aux_huber_masked_does_not_propagate, aux_huber_masked_covers_both_branches,
aux_bce_nan_mask_does_not_propagate
Cubins rebuilt: aux_heads (8736→10528 bytes, +20% for 4-head fwd/bwd),
aux_loss (6944→13344 bytes, +92% for 2 kernels).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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