diff options
| author | Scott Gasch <[email protected]> | 2026-08-29 00:30:53 -0700 |
|---|---|---|
| committer | Scott Gasch <[email protected]> | 2026-08-29 00:30:53 -0700 |
| commit | 917bf1260ae217bdcbdbc11c2c37cdb5d3a8eae9 (patch) | |
| tree | 8013781f51e53eaf1fe3d4f45367e920d4c39786 /tests/ecm016_only.ep_ | |
| parent | 366eebaf6b72fc6b56ea06a71f0276069a501dc7 (diff) | |
Switch to Crafty-style killer ordering; fix mvNullmoveRefutations type-mixing bug and add a quiet-refutation killer backfill.
Killer tiers now try both of this ply's own killers before either
ply-2-back one, matching Crafty's ordering. Two earlier attempts at
this same swap were reverted for regressing; this pass lands on top of
NumLeftoverMovesToSelect (more SelectBestWithHistory budget to reach
these lower-tier slots) and a real bug fix below, and beats interleaved
order head-to-head on solves, node count, and first-move beta cutoff
across the three curated suites.
The bug: mvNullmoveRefutations's empty-killer-slot backfill could only
ever contain a capturing move (TryNullmovePruning only wrote it inside
the capture-refutation branch), but IS_SAME_MOVE's mask includes the
pCaptured bits, so that backfilled value could never match a real
quiet candidate -- the backfill was silently dead code. Fixed by
recording genuinely quiet null-move refutations into a new, separate
mvNullmoveQuietRefutations array (kept separate so it can't clobber the
capture history mvNullmoveRefutations still needs for the
Botvinnik-Markoff same-piece-two-squares extension check) and
backfilling the regular killer table from that instead. The
check-evasion killer table intentionally does *not* get this backfill:
a null-move refutation can never legitimately be an escaping-check
move (null moves can't deliver check), so backfilling there risks
IS_SAME_MOVE cross-context false positives instead of the old
guaranteed-inert no-op.
Measured at sd10 across ecm_ringers/ecm_confident_quick/ecm_hard_quick
against head_reference (commit d11e973): 115/191 solves (vs. 116
baseline), 924.36M total nodes (vs. 933.23M), first-move beta cutoff
within 0.1-0.9 points of baseline on all three suites -- and clearly
better than the same fix under interleaved order (113/191 solves,
963.10M nodes), which loses to head_reference on every metric.
Co-Authored-By: Claude Sonnet 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01EortUUkDVpsfrbqshBJYJg
Diffstat (limited to 'tests/ecm016_only.ep_')
| -rw-r--r-- | tests/ecm016_only.ep_ | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/tests/ecm016_only.ep_ b/tests/ecm016_only.ep_ new file mode 100644 index 0000000..2a3dad3 --- /dev/null +++ b/tests/ecm016_only.ep_ @@ -0,0 +1,4 @@ +setboard 2rr2k1/1b3p1p/p4qpb/2R1n3/3p4/BP2P3/P3QPPP/3R1BKN b - - +solution Rxc5 +id "ECM.016" +go |