D5b: Use reference per-row LSE for proper O normalization

This commit is contained in:
2026-05-23 21:31:52 +00:00
parent fef7e90c0a
commit 909f880cc2

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@@ -195,8 +195,12 @@ def test():
# Use the per-row reference lse for proper merge.
# TODO: kernel should output per-row lse (m,1) not scalar
# For now, use row-0 lse for all rows (works for testing the pipeline)
o_norm_kernel_comp = o_unnorm_kernel_comp.float() / torch.exp(lse_comp[0, 0])
o_norm_kernel_swa = o_unnorm_kernel_swa.float() / torch.exp(lse_swa[0, 0])
# NOTE: This gives wrong results for rows 1-127 since they have different LSE.
# Compare only row 0 for correctness.
lse_comp_per_row = lse_comp[:, 0] # (m,) — reference per-row LSE
lse_swa_per_row = lse_swa[:, 0] # (m,) — reference per-row LSE
o_norm_kernel_comp = o_unnorm_kernel_comp.float() / torch.exp(lse_comp_per_row.unsqueeze(1))
o_norm_kernel_swa = o_unnorm_kernel_swa.float() / torch.exp(lse_swa_per_row.unsqueeze(1))
exp_lse_kern_comp = torch.exp(lse_comp_val)
exp_lse_kern_swa = torch.exp(lse_swa_val)