Wire NNUE eval into search, build the training pipeline, and add a fast

2026-10-20T16:26:44Z

move/eval-agreement benchmark against Stockfish (tests/lop) Implements the architecture decisions in src/docs/NNUE.md: HalfKAv2_hm feature set, int16/int8 quantization, per-ply accumulator backup for king moves, and a lazy-eval-ready integration into search.c/eval.c. Adds the full annotate_pgns/ training pipeline (extraction, K-fit/ labeling, quiet filtering, tensor building, training, export) plus an end-to-end orchestrator (run_nnue_pipeline.py) and validation tooling (sanity_check_net.py, compare_vs_stockfish_net.py). Adds tests/lop: a 10k-position list-of-positions benchmark comparing engine eval rank and move choice against pre-computed Stockfish/lc0 references, much cheaper than a full self-play match for day-to-day progress checks. First sd10-matched self-play result against classic HCE: LLR +2.28 (H1=+2.94), -72=119+169 over 360 games, confirming the net is "smarter per node" at matched depth. A real-time (--st 4) match is currently weaker (candidate loses ~3 plies of depth to a ~3.3-3.7x nps gap against an unrecalibrated search), consistent with NNUE.md's adoption-criterion section -- pruning/reduction constants still need retuning for the new eval's score scale before a fair real-time comparison is possible. Co-Authored-By: Claude Sonnet 5

NNUE accumulator incremental maintenance: MakeMove/UnmakeMove hookup

2026-10-15T22:21:26Z

Wires the live NNUE accumulator (SEARCHER_THREAD_CONTEXT.sNnueAccum[2], added in the previous commit) into real incremental maintenance, hooked directly into the piece-movement primitives rather than re-deriving move type from MOVE in a separate pass: - chess.h: shared HalfKAv2_hm feature-index formula/constants (NnueFeatureIndex and friends), moved here from nnuefeatures.c so the reference dump and the real hot-path code can never drift apart. Prototypes for NnueAccumAddFeature/RemoveFeature/Recompute and the (still placeholder, zero-initialized) embedding table. LiftPiece/PlacePiece/SlidePiece/SlidePawn/SlidePieceWithoutSigs signatures gain an NNUE_ACCUMULATOR sNnueAccum[2] parameter. - nnueaccum.c (new): the embedding table storage and the three accumulator operations. Written as straight-line 256-float loops, structured for -O3 -ffast-math auto-vectorization on this box's AVX2+FMA target; explicit SIMD intrinsics and real weight loading are separate, deliberately deferred follow-ups. - move.c: all 8 Lift/Place/Slide(WithoutSigs) primitives now keep sNnueAccum incrementally correct for both perspectives on every call -- except when the piece is a king, where each primitive skips its own-color perspective entirely (that perspective needs a full recompute, not a delta, since every HalfKAv2_hm feature in it is own-king-relative; computing an incremental update for it only to discard it unread would be wasted work). MakeMove backs up that perspective into the current ply's PLY_INFO.sNnueAccumBackup before a king moves (castling or a plain step) and overwrites it via NnueAccumRecompute once the board reflects the final position; UnmakeMove restores it from the same backup slot. DEBUG builds tag the backup with the color it belongs to and poison it after consumption, release builds carry no overhead for either. - nnuefeatures.c: now a thin board-walking wrapper around the shared chess.h formula instead of its own duplicated copy. - testmove.c: TestLiftPlaceSlidePiece passes a local (unread) dummy accumulator pair -- the only caller of these primitives outside move.c, and it never needed NNUE awareness, just a real argument. Verified via the full precommit_check.sh (all 4 gates, including the new combined DEBUG=1 TEST=1 self-test, which exercises MakeMove/ UnmakeMove heavily via TestMoveGenerator's perft counts and TestLegalMoveGenerator) -- confirms nothing crashes and no existing invariant breaks. Does NOT yet confirm the actual property that matters (incrementally-maintained accumulator == recompute-from- scratch) -- no test exercises that yet; next step. Co-Authored-By: Claude Sonnet 5

typhoon.git/src/nnueaccum.c, branch master

Wire NNUE eval into search, build the training pipeline, and add a fast

NNUE accumulator incremental maintenance: MakeMove/UnmakeMove hookup