KernelBench hard · RTX PRO 6000

KDA CUTLASS Claude Fable 5

manually audited: clean

Genuine three-kernel Triton chunked-KDA pipeline whose 2.1x-over-ceiling score comes from one real algorithmic idea: a TWO-LEVEL SEGMENTED SCAN that parallelizes the inter-chunk state recurrence every other entry (including FLA's own chunk_kda) runs serially. _kda_prepare builds the WY representation per chunk with the (I+L)^-1 inverse done as a Newton/Neumann doubling series entirely on tensor cores (exact for the nilpotent BT=64 strictly-lower L, covers up to L^63); _kda_seg_op composes the affine chunk update S -> diag(dn)S + kg^T(u - wS) into per-segment operators (M_seg, C_seg) in parallel; _kda_scan_seg recomputes each segment's entry state redundantly from those operators and replays its chunks with the state in registers. That converts the NT-long serial chain into ~NSEG plus parallel work — exactly what the thin-batch shapes (BH=4-16) need on 132 SMs. A CUDA-graph capture keyed on input data_ptr() removes launch overhead on ~45-90 us calls; the replay was EMPIRICALLY PROVEN to recompute from live buffers (below). In-trace score arc is a clean flywheel: 0.0175 -> 0.0283 -> 0.0366 -> 0.0485 -> 0.0511 (official graded 0.0527), with measured dead ends honestly reverted (multi-stream fork 0.0484 < 0.0511, rolled back). No forbidden ops, no grader edits, template_mutated=false.

20260721_223835_or-fable_anthropic_claude-fable-5_02_kda_cutlass