Commit Graph
3084 Commits
Author SHA1 Message Date
Joost VandeVondele e0fb783c30 Fix incorrect initialization
Fixes https://github.com/official-stockfish/Stockfish/issues/6505

Missing initialization seemingly resulting in side effects, as discussed in the issue.

Credit to Sopel for spotting the bug.

PR used as a testcase for CoPilot, doing the right thing https://github.com/official-stockfish/Stockfish/pull/6478#discussion_r2655467218

closes https://github.com/official-stockfish/Stockfish/pull/6511

No functional change
2026-01-01 15:51:09 +01:00
969285fa5d Shared pawn history
[Passed STC SMP](https://tests.stockfishchess.org/tests/view/694e506c572093c1986d7276):
```
LLR: 2.97 (-2.94,2.94) <0.00,2.00>
Total: 14992 W: 3924 L: 3653 D: 7415
Ptnml(0-2): 20, 1547, 4090, 1820, 19
```

[Passed LTC SMP](https://tests.stockfishchess.org/tests/live_elo/694ead61572093c1986d7365):
```
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 41146 W: 10654 L: 10342 D: 20150
Ptnml(0-2): 17, 3999, 12225, 4319, 13
```

[Passed a sanity check STC SMP post-refactoring](https://tests.stockfishchess.org/tests/view/69503997572093c1986d763a):
```
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 46728 W: 12178 L: 11863 D: 22687
Ptnml(0-2): 82, 5093, 12685, 5436, 68
```

(The large gain of the first STC was probably a fluke, and this result
is more reasonable!)

After shared correction history, Viz suggested we try sharing other
histories, especially `pawnHistory`. As far as we're aware, sharing
history besides correction history (like Caissa does) is novel. The
implementation follows the same pattern as shared correction history –
the size of the history table is scaled with
`next_power_of_two(threadsInNumaNode)` and the entry is prefetched in
`do_move`.

A bit of refactoring was done to accommodate this new history. Note that
we prefetch `&history->pawn_entry(*this)[pc][to]` rather than
`&history->pawn_entry(*this)` because unlike the other entries, each
entry contains multiple cache lines.

closes https://github.com/official-stockfish/Stockfish/pull/6498

Bench: 2503391

Co-authored-by: Michael Chaly <Vizvezdenec@gmail.com>
2025-12-28 14:59:09 +01:00
Stefan GeschwentnerandDisservin 1780c1fd6e For expected ALL nodes scale up reduction with depth dependent factor.
Passed STC:
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 141120 W: 36860 L: 36390 D: 67870
Ptnml(0-2): 470, 16441, 36314, 16819, 516
https://tests.stockfishchess.org/tests/view/694978e93c8768ca45072763

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 66576 W: 17078 L: 16700 D: 32798
Ptnml(0-2): 45, 7093, 18628, 7483, 39
https://tests.stockfishchess.org/tests/view/694bb608572093c1986d6ba6

closes https://github.com/official-stockfish/Stockfish/pull/6496

Bench: 2503391
2025-12-28 14:55:55 +01:00
KazAppsandDisservin b2e60960b3 Fix nonPawnKey
Fix incorrect nonPawnKey update

Passed non-reg SMP STC:
```
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 139424 W: 35792 L: 35690 D: 67942
Ptnml(0-2): 197, 15783, 37665, 15855, 212
```
https://tests.stockfishchess.org/tests/view/694b7b7e572093c1986d6b0d

Passed non-reg SMP LTC:
```
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 88880 W: 22863 L: 22718 D: 43299
Ptnml(0-2): 16, 8947, 26401, 9028, 48
```
https://tests.stockfishchess.org/tests/view/694d2ceb572093c1986d6fc8

fixes https://github.com/official-stockfish/Stockfish/issues/6492

closes https://github.com/official-stockfish/Stockfish/pull/6494

Bench: 2475788
2025-12-28 14:55:47 +01:00
Daniel MonroeandDisservin 1047f844d1 Simplify doDeeperSearch
Passed simplification STC
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 92096 W: 23888 L: 23728 D: 44480
Ptnml(0-2): 336, 10796, 23608, 10988, 320
https://tests.stockfishchess.org/tests/view/694b6b9d572093c1986d6ae0

Passed simplification LTC
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 50064 W: 12789 L: 12598 D: 24677
Ptnml(0-2): 24, 5350, 14103, 5521, 34
https://tests.stockfishchess.org/tests/view/694d49aa572093c1986d7021

closes https://github.com/official-stockfish/Stockfish/pull/6493

Bench: 2494221
2025-12-28 14:53:12 +01:00
FauziAkramandDisservin cd3a837324 Refine reduction logic based on next-ply cutoff count
Passed STC:
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 38208 W: 10076 L: 9754 D: 18378
Ptnml(0-2): 139, 4390, 9742, 4676, 157
https://tests.stockfishchess.org/tests/view/6945bb6446f342e1ec211d93

Passed LTC:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 64086 W: 16529 L: 16157 D: 31400
Ptnml(0-2): 34, 6808, 17990, 7174, 37
https://tests.stockfishchess.org/tests/view/69479d303c8768ca45072446

closes https://github.com/official-stockfish/Stockfish/pull/6489

Bench: 2442415
2025-12-28 14:49:19 +01:00
Taras VukandDisservin c475024be7 Incorporate statscore into history bonus
Passed STC:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 80128 W: 20879 L: 20498 D: 38751
Ptnml(0-2): 274, 9318, 20496, 9705, 271
https://tests.stockfishchess.org/tests/view/6945d11f3c8768ca45072218

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 134298 W: 34497 L: 33983 D: 65818
Ptnml(0-2): 81, 14334, 37812, 14834, 88
https://tests.stockfishchess.org/tests/view/6947bf033c8768ca45072491

closes https://github.com/official-stockfish/Stockfish/pull/6488

Bench: 2325401
2025-12-23 21:42:45 +01:00
FauziAkramandDisservin 4d4c6ebd02 Simplify doDeeperSearch formula
Passed STC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 211776 W: 54939 L: 54911 D: 101926
Ptnml(0-2): 714, 24971, 54484, 25011, 708
https://tests.stockfishchess.org/tests/view/6938971875b70713ef796b70

Passed LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 216774 W: 55346 L: 55326 D: 106102
Ptnml(0-2): 105, 23599, 60980, 23577, 126
https://tests.stockfishchess.org/tests/view/693fc91f46f342e1ec20f9f6

closes https://github.com/official-stockfish/Stockfish/pull/6486

Bench: 3267755
2025-12-23 21:42:45 +01:00
Michael ChalyandDisservin 447f66acac Less penalty for quiet late moves that didn't beat the best move.
This moves since they are late in move ordering probably already have pretty bad stats anyway.
Passed STC:
https://tests.stockfishchess.org/tests/view/6943bcd546f342e1ec210e25
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 96704 W: 25206 L: 24798 D: 46700
Ptnml(0-2): 357, 11244, 24767, 11602, 382
Passed LTC:
https://tests.stockfishchess.org/tests/view/6946a8723c8768ca450722f0
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 89814 W: 23193 L: 22770 D: 43851
Ptnml(0-2): 53, 9532, 25321, 9941, 60
bench 2717363

closes https://github.com/official-stockfish/Stockfish/pull/6485

Bench: 2791988
2025-12-23 21:42:45 +01:00
anematodeandDisservin 1a67ccc72e Share correction history between threads
We did quite a few tests because this is a pretty involved change with
unknown scaling behavior, but results are decent.

[STC 10+0.1 1th, non-regression](https://tests.stockfishchess.org/tests/live_elo/6941ce3b46f342e1ec210180)
```
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 83200 W: 21615 L: 21452 D: 40133
Ptnml(0-2): 247, 9064, 22844, 9169, 276
```

[STC 5+0.05 8th](https://tests.stockfishchess.org/tests/live_elo/693dc38346f342e1ec20f555)
```
LLR: 3.48 (-2.94,2.94) <0.00,2.00>
Total: 58536 W: 15067 L: 14688 D: 28781
Ptnml(0-2): 87, 6474, 15781, 6825, 101
```

[LTC 20+0.2 8th](https://tests.stockfishchess.org/tests/live_elo/693f2afb46f342e1ec20f847)
```
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 27716 W: 7211 L: 6925 D: 13580
Ptnml(0-2): 8, 2674, 8207, 2962, 7
```

[LTC 10+0.1 64th](https://tests.stockfishchess.org/tests/live_elo/694003aa46f342e1ec20fac4):
```
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 16918 W: 4439 L: 4182 D: 8297
Ptnml(0-2): 3, 1493, 5213, 1744, 6
```

[NUMA test, 5+0.05 256th](https://tests.stockfishchess.org/tests/view/6941ee4e46f342e1ec210203)
```
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 7124 W: 1910 L: 1678 D: 3536
Ptnml(0-2): 0, 560, 2211, 790, 1
```

[LTC 60+0.6 64th](https://tests.stockfishchess.org/tests/live_elo/6940a85346f342e1ec20fcde):
```
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 15504 W: 4045 L: 3826 D: 7633
Ptnml(0-2): 0, 1002, 5530, 1219, 1
```

Bonus (courtesy of Viz): The 1 double kill in this last test was master
blundering a cool mate in 3: https://lichess.org/jyNZuRl4

Basically the idea here is to share correction history between threads.
That way, T1 can use the correction values produced by T2, which already
searched positions with that pawn structure etc., so that T1 can search
more efficiently. The table size per thread is about the same, so we
shouldn't get a large increase in hash collisions; in fact, I'd expect a
lower collision rate overall.

Although I came up with and implemented the idea independently,
[Caissa](https://github.com/Witek902/Caissa) was the first engine to
implement corrhist sharing (and corrhist in the first place) – this idea
is not completely novel.

The table size is rounded to a power of two. In particular, it's `65536
* nextPowerOfTwo(threadCount)`. That way, the indexing operation becomes
an AND of the key bits with a mask, rather than something more expensive
(e.g., a `mul_hi64`-style approach or a modulo).

The updates are racy, like the TT, but because `entry` is hoisted into a
register, there's no risk of writing back a value that's out of the
designated range `[-D, D]`. Various attempts at rewriting using atomics
led to substantial slowdowns, so we begrudgingly ignored the functions
in thread sanitizer, but at some point we'd like to make this better.

We allocate one shared correction history per NUMA node, because the
penalty associated with crossing nodes is substantial – I get a 40% hit
with NPS=4 and 256 threads, which is intolerable. With separate tables
per NUMA node I get a 6% penalty for nodes per second, which isn't ideal
but apparently compensated for.

closes https://github.com/official-stockfish/Stockfish/pull/6478

Bench: 2690604

Co-authored-by: Disservin <disservin.social@gmail.com>
2025-12-23 21:42:29 +01:00
AliceRoseliaandDisservin c467fe5ba4 Simplify futility pruning
Passed non regression STC:
https://tests.stockfishchess.org/tests/view/693e642c46f342e1ec20f68d
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 107968 W: 28080 L: 27937 D: 51951
Ptnml(0-2): 381, 12708, 27626, 12925, 344

Passed non regression LTC:
https://tests.stockfishchess.org/tests/view/693ff10c46f342e1ec20fa6a
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 334266 W: 85271 L: 85370 D: 163625
Ptnml(0-2): 179, 36395, 94086, 36292, 181

closes https://github.com/official-stockfish/Stockfish/pull/6484

Bench: 2987379
2025-12-21 15:43:32 +01:00
Daniel MonroeandDisservin b4b01d0ca2 Remove rootDepth condition in newDepth clamping
Passed simplification STC
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 132256 W: 34462 L: 34347 D: 63447
Ptnml(0-2): 470, 15625, 33833, 15720, 480
https://tests.stockfishchess.org/tests/view/69325fe0a24a6df719fcca16

Passed simplification LTC
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 128220 W: 32503 L: 32392 D: 63325
Ptnml(0-2): 94, 13900, 35982, 14069, 65
https://tests.stockfishchess.org/tests/view/6934c2b3a24a6df719fcdf1e

closes https://github.com/official-stockfish/Stockfish/pull/6472

Bench: 2926903
2025-12-21 15:43:32 +01:00
Daniel MonroeandDisservin 8449e5eb9d Remove non-functional term in isShuffling
closes https://github.com/official-stockfish/Stockfish/pull/6462

No functional change
2025-12-21 15:43:32 +01:00
FauziAkramandDisservin 5edfabd070 Fix Typo
closes https://github.com/official-stockfish/Stockfish/pull/6436

No functional change
2025-12-21 15:22:06 +01:00
Daniel MonroeandJoost VandeVondele 5297ba0a1a Move hindsight reductions above cutoffs
Passed STC
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 52640 W: 13701 L: 13361 D: 25578
Ptnml(0-2): 168, 6143, 13356, 6487, 166
https://tests.stockfishchess.org/tests/view/6918dc407ca8781852332339

Passed LTC
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 207690 W: 53187 L: 52520 D: 101983
Ptnml(0-2): 93, 22515, 57994, 23118, 125
https://tests.stockfishchess.org/tests/view/6919dd307ca87818523324c7

closes https://github.com/official-stockfish/Stockfish/pull/6448

Bench: 2912398
2025-12-01 17:35:34 +01:00
FauziAkramandDisservin c95386256e Simplify the highBestMoveEffort formula in Time management
Passed STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 22272 W: 5885 L: 5655 D: 10732
Ptnml(0-2): 76, 2329, 6108, 2535, 88
https://tests.stockfishchess.org/tests/view/69244d07ba083df4ca63e02b

Passed LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 48690 W: 12405 L: 12221 D: 24064
Ptnml(0-2): 29, 4755, 14597, 4931, 33
https://tests.stockfishchess.org/tests/view/6924de9aba083df4ca63e327

closes https://github.com/official-stockfish/Stockfish/pull/6451

No functional change
2025-11-30 21:58:35 +01:00
Shawn XuandDisservin 45d034fa50 Formatting fixups
closes https://github.com/official-stockfish/Stockfish/pull/6446

No functional change
2025-11-30 21:58:35 +01:00
pb00067andDisservin c73f21df97 Fix for SF getting stuck during search (issue #5023)
Among several passed similar versions this is the simpliest one.

Passed STC non-regression
https://tests.stockfishchess.org/tests/view/691f3b4aacb6dbdf23d07d11
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 126368 W: 32607 L: 32489 D: 61272
Ptnml(0-2): 408, 13974, 34298, 14100, 404

Passed LTC non-regression
https://tests.stockfishchess.org/tests/view/69209712acb6dbdf23d0836a
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 114786 W: 29097 L: 28976 D: 56713
Ptnml(0-2): 53, 11841, 33488, 11954, 57

closes https://github.com/official-stockfish/Stockfish/pull/6447

Bench: 2941767
2025-11-30 21:58:34 +01:00
Daniel MonroeandJoost VandeVondele d9fd516547 Post-NNUEv10 tune
Tune search parameters after the switch to NNUEv10.

The change is neutral at STC but increases with the TC. The main changes are more aggressive corrections, futility pruning, and extensions.

Failed STC
LLR: -2.96 (-2.94,2.94) <0.00,2.00>
Total: 108320 W: 27616 L: 27719 D: 52985
Ptnml(0-2): 332, 12833, 27884, 12828, 283
https://tests.stockfishchess.org/tests/view/69212e623b03dd3a060e6114

Passed LTC
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 43272 W: 11117 L: 10788 D: 21367
Ptnml(0-2): 20, 4543, 12180, 4874, 19
https://tests.stockfishchess.org/tests/view/692130813b03dd3a060e6123

Passed VLTC
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 22714 W: 5840 L: 5581 D: 11293
Ptnml(0-2): 2, 2152, 6795, 2401, 7
https://tests.stockfishchess.org/tests/view/6921387b3b03dd3a060e6191

Passed VLTC SMP
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 11868 W: 3142 L: 2896 D: 5830
Ptnml(0-2): 0, 1007, 3676, 1249, 2
https://tests.stockfishchess.org/tests/view/69212e953b03dd3a060e611b

closes https://github.com/official-stockfish/Stockfish/pull/6444

bench 2907929
2025-11-22 07:56:47 +01:00
Shawn XuandJoost VandeVondele 035cb146d4 Do more futility pruning
closes https://github.com/official-stockfish/Stockfish/pull/6433

Bench: 2469519
2025-11-17 14:03:02 +01:00
Timothy HerchenandJoost VandeVondele b083049fe0 Use non-locking operations for nodes count and tbHits
fetch_add and friends must produce a locking instruction because they guarantee
consistency in the presence of multiple writers. Because only one thread ever
writes to nodes and tbHits, we may use relaxed load and store to emit regular
loads and stores (on both x86-64 and arm64), while avoiding undefined behavior
and miscounting nodes.

Credit must go to Arseniy Surkov of Reckless (codedeliveryservice) for
uncovering this performance gotcha.

failed yellow as a gainer on fishtest:
LLR: -2.95 (-2.94,2.94) <0.00,2.00>
Total: 219616 W: 57165 L: 57105 D: 105346
Ptnml(0-2): 732, 24277, 59720, 24357, 722
https://tests.stockfishchess.org/tests/view/69086abfea4b268f1fac2809

potential small speedup on large core system:
```
==== master ====
1 Nodes/second : 294269736
2 Nodes/second : 295217629
Average (over 2):  294743682
==== patch ====
1 Nodes/second : 299003603
2 Nodes/second : 298111320
Average (over 2):  298557461
```

closes https://github.com/official-stockfish/Stockfish/pull/6392

No functional change
2025-11-17 13:24:32 +01:00
Robert NurnbergandJoost VandeVondele 4b71d8e202 Allow time checking after each DTZ probe
This PR allows for time checking within Tablebases::rank_root_moves(). The
principal application for now is syzygy_extend_pv().

In the past, Stockfish suffered some time losses at e.g. TCEC when the HDD with
the DTZ tables was too slow for the chosen move overhead setting, see #5894.

```
> ./fastchess -engine name="patch" cmd=./stockfish.patch -engine name="master" cmd=./stockfish.master -each tc=10+0.1 option.SyzygyPath=/disk1/syzygy/3-4-5-6/WDL:/disk2/syzygy/3-4-5-6/DTZ -draw movenumber=34 movecount=8 score=20 -openings file=UHO_Lichess_4852_v1.epd format=epd -rounds 50 -repeat -concurrency 16
...
Results of patch vs master (10+0.1, 1t, 16MB, UHO_Lichess_4852_v1.epd):
Elo: 59.64 +/- 35.35, nElo: 117.61 +/- 68.10
LOS: 99.96 %, DrawRatio: 56.00 %, PairsRatio: 4.50
Games: 100, Wins: 34, Losses: 17, Draws: 49, Points: 58.5 (58.50 %)
Ptnml(0-2): [0, 4, 28, 15, 3], WL/DD Ratio: 0.87
--------------------------------------------------

Player: master
  Timeouts: 19
  Crashed: 0

Finished match
```

closes https://github.com/official-stockfish/Stockfish/pull/6422

No functional change
2025-11-14 17:38:55 +01:00
Daniel MonroeandJoost VandeVondele a191791f46 Clean up code and comments
closes https://github.com/official-stockfish/Stockfish/pull/6416

No functional change
2025-11-14 17:30:55 +01:00
AliceRoseliaandJoost VandeVondele 7b7a9485d6 Simplify indexing
Removes 1 function (from_to) from the Move type, change them to simpler raw.
Remove the "and" use in the correction history structure calculation. Adjust
the indexing.

Passed simplification STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 42880 W: 11327 L: 11113 D: 20440
Ptnml(0-2): 161, 4852, 11212, 5042, 173
https://tests.stockfishchess.org/tests/view/690593b8ea4b268f1fac1e8a

Passed simplification LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 43560 W: 11276 L: 11079 D: 21205
Ptnml(0-2): 17, 4679, 12197, 4864, 23
https://tests.stockfishchess.org/tests/view/6906f819ea4b268f1fac216b

closes https://github.com/official-stockfish/Stockfish/pull/6391

Bench: 2523092
2025-11-14 17:28:17 +01:00
FauziAkramandJoost VandeVondele df88db16c6 Simplify NMP reduction formula
Passed STC:
LLR: 2.97 (-2.94,2.94) <-1.75,0.25>
Total: 178912 W: 46625 L: 46559 D: 85728
Ptnml(0-2): 540, 21167, 45975, 21235, 539
https://tests.stockfishchess.org/tests/view/69060677ea4b268f1fac1f25

Passed LTC:
LLR: 2.99 (-2.94,2.94) <-1.75,0.25>
Total: 140988 W: 36278 L: 36176 D: 68534
Ptnml(0-2): 82, 15520, 39215, 15568, 109
https://tests.stockfishchess.org/tests/view/6908bc32ea4b268f1fac288f

closes https://github.com/official-stockfish/Stockfish/pull/6416

bench: 2959834
2025-11-14 17:24:16 +01:00
Guenther DemetzandJoost VandeVondele 4784ff2b3b Unify do_move & do_null_move workload
While being there also remove and unused assignment.

Tested for non-regression at STC:
https://tests.stockfishchess.org/tests/view/69060d81ea4b268f1fac1f36
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 94496 W: 24570 L: 24421 D: 45505
Ptnml(0-2): 264, 10145, 26275, 10306, 258

closes https://github.com/official-stockfish/Stockfish/pull/6383

no functional change
2025-11-13 22:26:35 +01:00
Timothy HerchenandJoost VandeVondele fa4f05d3ef Don't copy around DirtyThreats
The contents of DirtyThreats gets memcpyed twice for each call to do_move.
(Return value optimization doesn't apply to the do_move function itself because
it constructs a std::pair, so it gets copied; and the calls to reset also
require a copy.) This patch inserts the dirty info in place.

Sometimes the caller of do_move ignores the DirtyThreats info, so we pass in
scratch objects. I found that stack-allocating these scratch objects was bad on
Fishtest, so I begrudgingly put them in the Position struct. Both templating
the do_move function on whether dirty threats are needed and putting a
null-check branch for each use of dirty threats were slowdowns locally. Of
course, nothing prevents a future attempt at cleaning this up.

passed STC
LLR: 2.96 (-2.94,2.94) <0.00,2.00>
Total: 68448 W: 17770 L: 17418 D: 33260
Ptnml(0-2): 198, 7425, 18630, 7769, 202
https://tests.stockfishchess.org/tests/view/6914c01a7ca87818523318ba

closes https://github.com/official-stockfish/Stockfish/pull/6414

No functional change
2025-11-13 22:17:03 +01:00
Daniel MonroeandJoost VandeVondele 7ac8e62219 Refine constant in correction history update
Passed STC
LLR: 3.04 (-2.94,2.94) <0.00,2.00>
Total: 250112 W: 65277 L: 64635 D: 120200
Ptnml(0-2): 841, 29326, 64134, 29860, 895
https://tests.stockfishchess.org/tests/view/69096c46ea4b268f1fac2a39

Passed LTC
LLR: 2.96 (-2.94,2.94) <0.50,2.50>
Total: 142908 W: 37141 L: 36604 D: 69163
Ptnml(0-2): 100, 15478, 39742, 16053, 81
https://tests.stockfishchess.org/tests/view/690e7dfbec1d00d2c195c351

closes https://github.com/official-stockfish/Stockfish/pull/6405

bench 2613869
2025-11-13 22:10:30 +01:00
+1 8e5392d79a Update NNUE architecture to SFNNv10 with Threat Inputs and net nn-49c1193b131c.nnue
This commit introduces Full Threat Input features, which are a subset of Piece(Square)-Piece(Square) pairs. In any given position, the active features consist of pairs where the second piece’s square lies in the attack set of the first piece. This is an extremely simplified explanation that leaves out many details. The already-used HalfKAv2_hm feature set completes the input features.
Minor quantization changes have also been made.

The net nn-49c1193b131c.nnue was trained by vondele using the following setup: https://github.com/vondele/nettest/blob/7de71238e9b295e3f88ed7c9c5936af632c9b981/threats.yaml

A graphical version of an earlier scheme (with less refinement) that illustrates the core concepts can be found attached.
[NewInputs.pdf](https://github.com/user-attachments/files/23478441/NewInputs.pdf)

Further information, as well as a brief description of the history of development, can be found attached.
[Stockfish threat inputs PR summary.pdf](https://github.com/user-attachments/files/23478634/Stockfish.threat.inputs.PR.summary.pdf)

This has been a huge effort spanning over half a year, with the original [discussion thread](https://discord.com/channels/435943710472011776/1336647760388034610) reaching over 11k messages. Thanks to everyone who has contributed.

Monty PRs:
https://github.com/official-monty/Monty/pull/87 (Initial threat input PR)
https://github.com/official-monty/Monty/pull/114 (Fixed threat indexing to take into account colour correctly)
https://github.com/official-monty/Monty/pull/116 (i8 quantisation of weights whilst keeping calculations in i16)

Yukari commit:
https://github.com/yukarichess/yukari/commit/2d482c64a79cec03cf4987d5289334b9cdc737bc (Threat inputs merged)

Plentychess PRs:
https://github.com/Yoshie2000/PlentyChess/pull/400 (Threat inputs merged)
https://github.com/Yoshie2000/PlentyChess/pull/411 (Threat input weights quantised to i8)

Passed STC:
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 63424 W: 16956 L: 16591 D: 29877
Ptnml(0-2): 276, 7522, 15797, 7795, 322
https://tests.stockfishchess.org/tests/view/69105b3dec1d00d2c195c569

Passed LTC:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 27876 W: 7417 L: 7110 D: 13349
Ptnml(0-2): 23, 3033, 7530, 3318, 34
https://tests.stockfishchess.org/tests/view/6910d817ec1d00d2c195c66e

Passed VVLTC (Hash accidentally set to 1/2 normal value for both sides):
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 12458 W: 3353 L: 3102 D: 6003
Ptnml(0-2): 0, 1106, 3767, 1355, 1
https://tests.stockfishchess.org/tests/view/69115a26ec1d00d2c195c7cd

This version has also passed non-regression LTC against the originally passed version:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 51144 W: 13086 L: 12903 D: 25155
Ptnml(0-2): 22, 5167, 15018, 5336, 29
https://tests.stockfishchess.org/tests/view/69138a317ca87818523314bf

LTC elo estimate on ARM:
1 patch     :    13.9    1.9  38296.5   73728    52
2 master    :     0.0   ----  35431.5   73728    48

closes https://github.com/official-stockfish/Stockfish/pull/6411

bench: 2626086

Co-authored-by: Shawn Xu <xu107288696@gmail.com>
Co-authored-by: Timothy Herchen <timothy.herchen@gmail.com>
Co-authored-by: Viren6 <94880762+Viren6@users.noreply.github.com>
Co-authored-by: Yoshie2000 <patrick.leonhardt@gmx.net>
Co-authored-by: Joost Vandevondele <Joost.VandeVondele@gmail.com>
Co-authored-by: rn5f107s2 <clemens.lerchl@gmail.com>
Co-authored-by: cj5716 <125858804+cj5716@users.noreply.github.com>
Co-authored-by: AliceRoselia <63040919+AliceRoselia@users.noreply.github.com>
Co-authored-by: Linmiao Xu <linmiao.xu@gmail.com>
Co-authored-by: Disservin <disservin.social@gmail.com>
2025-11-12 10:49:39 +01:00
FauziAkramandJoost VandeVondele bc9f08731f Simplify Futility pruning formula
Passed STC:
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 170112 W: 44266 L: 44193 D: 81653
Ptnml(0-2): 599, 20062, 43611, 20235, 549
https://tests.stockfishchess.org/tests/view/68f50b94637acd2a11e721ad

Passed LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 164658 W: 42393 L: 42318 D: 79947
Ptnml(0-2): 120, 18127, 45747, 18228, 107
https://tests.stockfishchess.org/tests/view/68fa6683637acd2a11e72ac3

closes https://github.com/official-stockfish/Stockfish/pull/6389

bench: 2351426
2025-11-01 11:39:00 +01:00
Shawn XuandJoost VandeVondele cd7880c030 Simplify Corrhist Bonus
Passed Non-regression STC:
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 187776 W: 48687 L: 48631 D: 90458
Ptnml(0-2): 570, 22327, 48090, 22279, 622
https://tests.stockfishchess.org/tests/view/68f58019637acd2a11e72233

Passed Non-regression LTC:
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 159378 W: 41027 L: 40946 D: 77405
Ptnml(0-2): 122, 17645, 44078, 17718, 126
https://tests.stockfishchess.org/tests/view/68fe7492637acd2a11e73090

closes https://github.com/official-stockfish/Stockfish/pull/6385

Bench: 2458738
2025-11-01 11:36:33 +01:00
Shawn XuandJoost VandeVondele 0351652995 Simplify Pawn History Bonus
Passed Non-regression STC:
LLR: 2.98 (-2.94,2.94) <-1.75,0.25>
Total: 122016 W: 31655 L: 31525 D: 58836
Ptnml(0-2): 388, 14317, 31474, 14435, 394
https://tests.stockfishchess.org/tests/view/68f57e66637acd2a11e7221d

Passed Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 81348 W: 21016 L: 20858 D: 39474
Ptnml(0-2): 45, 8793, 22841, 8949, 46
https://tests.stockfishchess.org/tests/view/68f9e2d9637acd2a11e72997

closes https://github.com/official-stockfish/Stockfish/pull/6382

Bench: 2370893
2025-11-01 11:32:53 +01:00
Daniel MonroeandJoost VandeVondele c9a2aff485 Simplify correction update condition
Passed non-regression STC
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 95136 W: 24722 L: 24564 D: 45850
Ptnml(0-2): 307, 11139, 24522, 11289, 311
https://tests.stockfishchess.org/tests/view/68e5034ea017f472e763dc5a

Passed non-regression LTC
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 256440 W: 65854 L: 65873 D: 124713
Ptnml(0-2): 144, 28287, 71375, 28272, 142
https://tests.stockfishchess.org/tests/view/68e71ae4a017f472e763e291

closes https://github.com/official-stockfish/Stockfish/pull/6375

bench 2216361
2025-11-01 11:29:47 +01:00
Daniel MonroeandJoost VandeVondele 013d42914f Simplify static eval bonus
Passed non-regression STC
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 176896 W: 45998 L: 45933 D: 84965
Ptnml(0-2): 609, 20845, 45451, 20958, 585
https://tests.stockfishchess.org/tests/view/68e5e48ba017f472e763dd21

Passed non-regression LTC
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 77682 W: 20046 L: 19884 D: 37752
Ptnml(0-2): 41, 8404, 21786, 8572, 38
https://tests.stockfishchess.org/tests/view/68ee71e328e6d77fcff9fd68

closes https://github.com/official-stockfish/Stockfish/pull/6374

bench 2101654
2025-11-01 11:27:27 +01:00
Daniel MonroeandJoost VandeVondele fd3c563f57 Simplify r50 condition in cutoff
Passed non-regression STC
LLR: 3.11 (-2.94,2.94) <-1.75,0.25>
Total: 114560 W: 29832 L: 29689 D: 55039
Ptnml(0-2): 332, 12302, 31869, 12445, 332
https://tests.stockfishchess.org/tests/view/68e38587fa806e2e8393d4a9

Passed non-regression LTC
LLR: 2.99 (-2.94,2.94) <-1.75,0.25>
Total: 256272 W: 65817 L: 65832 D: 124623
Ptnml(0-2): 137, 25528, 76817, 25521, 133
https://tests.stockfishchess.org/tests/view/68e69b47a017f472e763e065

closes https://github.com/official-stockfish/Stockfish/pull/6373

Bench: 2438327
2025-11-01 11:20:23 +01:00
Daniel MonroeandJoost VandeVondele 9e071f3561 Simplify best move effort
Passed non-regression STC
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 44224 W: 11614 L: 11403 D: 21207
Ptnml(0-2): 147, 4936, 11726, 5165, 138
https://tests.stockfishchess.org/tests/view/68e9410ed323fd15c04e3a87

Passed non-regression LTC
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 109788 W: 28223 L: 28096 D: 53469
Ptnml(0-2): 60, 11493, 31657, 11628, 56
https://tests.stockfishchess.org/tests/view/68eb5ac0a23744016c14af1d

closes https://github.com/official-stockfish/Stockfish/pull/6371

No functional change
2025-11-01 11:18:00 +01:00
pb00067andJoost VandeVondele fa3b4ef5af Improve retrograde analisys and matefinding capability
fixes https://github.com/official-stockfish/Stockfish/issues/6328

Before calling search(depth), the patch ensures that depth is at least 1
whenever we encounter a decisive score in the transposition table (TT). This
prevents search(depth) from being executed by qsearch, which would otherwise
ignore that information.  Typically, decisive TT hits occur when analyzing a
mating sequence backward. Due to the nature of Iterative Deepening (IID), such
scores are usually first found at depth 0. Without this patch, valuable
information can be lost because qsearch may overwrite the TT entry by replacing
the value with a static evaluation, even though the node was already processed
at a higher depth. This is also why the engine sometimes loses track of an
already discovered mate.

Using ..\sf\patch.exe on matetrack.epd with --nodes 1000000
Engine ID:     Stockfish dev-20251015-nogit
Total FENs:    6554
Found mates:   3437
Best mates:    2438

Using ..\sf\master.exe on matetrack.epd with --nodes 1000000
Engine ID:     Stockfish dev-20251015-nogit
Total FENs:    6554
Found mates:   3337
Best mates:    2407

Passed STC
https://tests.stockfishchess.org/tests/view/68fa3fa7637acd2a11e72a79
LLR: 3.55 (-2.94,2.94) <0.00,2.00>
Total: 134144 W: 34960 L: 34471 D: 64713
Ptnml(0-2): 376, 14199, 37459, 14636, 402

Failed LTC
https://tests.stockfishchess.org/tests/view/68ffc1b5637acd2a11e73377
LLR: -3.10 (-2.94,2.94) <0.50,2.50>
Total: 75360 W: 19423 L: 19519 D: 36418
Ptnml(0-2): 38, 7553, 22605, 7435, 49

closes https://github.com/official-stockfish/Stockfish/pull/6386

bench: 2530552
2025-11-01 11:02:00 +01:00
shaowyxandJoost VandeVondele a49b52cf69 Revert malus and associated coefficient parameters resulting from using only quiet moves
Following #6226 and #6256, this patch ultimately corresponds to the revert of #6200.
Parameters were tuned on 60k LTC games.

STC (10+0.1 th1) was accepted:
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 167488 W: 43573 L: 43063 D: 80852
Ptnml(0-2): 506, 19644, 43004, 20014, 576
https://tests.stockfishchess.org/tests/view/68f526a4637acd2a11e721c2

LTC (60+0.6 th1) was accepted:
LLR: 2.99 (-2.94,2.94) <0.50,2.50>
Total: 61068 W: 15882 L: 15510 D: 29676
Ptnml(0-2): 31, 6578, 16949, 6940, 36
https://tests.stockfishchess.org/tests/view/68fa1968637acd2a11e72a0a

Non-regression VLTC (180+1.8 th1) was accepted:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 50380 W: 13087 L: 12905 D: 24388
Ptnml(0-2): 5, 5018, 14962, 5200, 5
https://tests.stockfishchess.org/tests/view/68fdc6e5637acd2a11e72f33

closes https://github.com/official-stockfish/Stockfish/pull/6378

Bench: 2530552
2025-11-01 10:48:40 +01:00
Taras VukandJoost VandeVondele b9e3e7921b Increase NMP reduction when improving
Passed STC:
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 52896 W: 13904 L: 13565 D: 25427
Ptnml(0-2): 186, 6022, 13706, 6335, 199
https://tests.stockfishchess.org/tests/view/68e67d02a017f472e763dfaf

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 168354 W: 43750 L: 43163 D: 81441
Ptnml(0-2): 81, 18284, 46882, 18827, 103
https://tests.stockfishchess.org/tests/view/68e79d7ba017f472e763e352

closes https://github.com/official-stockfish/Stockfish/pull/6361

bench: 2537382
2025-11-01 10:28:02 +01:00
Daniel MonroeandJoost VandeVondele e7a4708ad5 Remove condition in qsearch
Instead of skipping non-captures when pawn history is exceptionally high, skip all non-captures

Passed non-regression STC
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 38016 W: 10018 L: 9795 D: 18203
Ptnml(0-2): 155, 4346, 9755, 4625, 127
https://tests.stockfishchess.org/tests/view/68e43d4aa017f472e763db2e

Passed rebased non-regression LTC
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 96048 W: 24854 L: 24710 D: 46484
Ptnml(0-2): 47, 10504, 26780, 10644, 49
https://tests.stockfishchess.org/tests/view/68e59352a017f472e763dcf9

closes https://github.com/official-stockfish/Stockfish/pull/6355

bench 2343840
2025-10-14 17:32:32 +02:00
Daniel SamekandJoost VandeVondele e18ed795f2 Introduce 4-ply continuation correction history
Passed STC:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 113984 W: 29752 L: 29323 D: 54909
Ptnml(0-2): 376, 13191, 29435, 13608, 382
https://tests.stockfishchess.org/tests/view/68dc3576fa806e2e8393bd93

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 80154 W: 20823 L: 20417 D: 38914
Ptnml(0-2): 47, 8600, 22383, 8994, 53
https://tests.stockfishchess.org/tests/view/68df83e0fa806e2e8393cbe8

Passed non-regression VLTC (rebased):
LLR: 2.98 (-2.94,2.94) <-1.75,0.25>
Total: 38158 W: 9992 L: 9805 D: 18361
Ptnml(0-2): 3, 3406, 12075, 3591, 4
https://tests.stockfishchess.org/tests/view/68e22f2afa806e2e8393d0ed

closes https://github.com/official-stockfish/Stockfish/pull/6345

bench 2169281
2025-10-07 11:50:51 +02:00
Shawn XuandJoost VandeVondele e5c2dc5edd remove clang-format workaround
closes https://github.com/official-stockfish/Stockfish/pull/6332

No functional change
2025-10-05 09:33:42 +02:00
FauziAkramandJoost VandeVondele 7a7c033a86 Tweak Correction History Bonus Asymmetrically
Refine the correction history update by applying an asymmetric bonus based on the type of evaluation error. It differentiates between negative corrections and positive corrections.

Passed STC:
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 165184 W: 43314 L: 42807 D: 79063
Ptnml(0-2): 551, 19391, 42261, 19778, 611
https://tests.stockfishchess.org/tests/view/68cae49902c43c969fe7f008

Passed LTC:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 243234 W: 62765 L: 62029 D: 118440
Ptnml(0-2): 163, 25996, 68551, 26756, 151
https://tests.stockfishchess.org/tests/view/68d1c50dfa806e2e8393aa1f

closes https://github.com/official-stockfish/Stockfish/pull/6338

Bench: 2746404
2025-10-05 09:25:44 +02:00
nicolasduhamelandJoost VandeVondele 5c93616a3f Adjust aspiration window
Narrow the aspiration window after fail high.

Passed STC:
LLR: 2.98 (-2.94,2.94) <0.00,2.00>
Total: 51296 W: 13550 L: 13207 D: 24539
Ptnml(0-2): 165, 5971, 13052, 6276, 184
https://tests.stockfishchess.org/tests/view/68d99afffa806e2e8393b7ae

Passed LTC;
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 87780 W: 22795 L: 22375 D: 42610
Ptnml(0-2): 52, 9340, 24694, 9744, 60
https://tests.stockfishchess.org/tests/view/68dae0a6fa806e2e8393baad

See the comments in #6293 discussing the mechanisms leading to issue #6296

closes https://github.com/official-stockfish/Stockfish/pull/6337

Bench: 2336606
2025-10-05 09:23:02 +02:00
Shawn XuandJoost VandeVondele c62e71e78f Simplify a separate term in low ply history bonus formula
Passed Non-regression STC:
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 211200 W: 54887 L: 54860 D: 101453
Ptnml(0-2): 719, 24894, 54296, 25023, 668
https://tests.stockfishchess.org/tests/view/68c21e7f59efc3c96b6112c8

Passed Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 217842 W: 55587 L: 55568 D: 106687
Ptnml(0-2): 130, 23651, 61313, 23724, 103
https://tests.stockfishchess.org/tests/view/68c230ec59efc3c96b61135a

closes https://github.com/official-stockfish/Stockfish/pull/6307

Bench: 2070860
2025-09-28 21:19:22 +02:00
FauziAkramandJoost VandeVondele 40aeb5a411 Simplify away conthist 0
While at it, I also added the scaler note to the Lmrdepth/history formula.

Passed STC:
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 25376 W: 6660 L: 6423 D: 12293
Ptnml(0-2): 77, 2947, 6403, 3184, 77
https://tests.stockfishchess.org/tests/view/68c1ccf759efc3c96b610deb

Passed LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 208464 W: 53371 L: 53342 D: 101751
Ptnml(0-2): 110, 22776, 58426, 22815, 105
https://tests.stockfishchess.org/tests/view/68c1d04b59efc3c96b610e13

closes https://github.com/official-stockfish/Stockfish/pull/6304

Bench: 2029296
2025-09-28 21:14:28 +02:00
Shawn XuandJoost VandeVondele 415a1ad426 Simplify Probcut Clamp Further
Passed Non-regression STC:
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 157984 W: 41116 L: 41030 D: 75838
Ptnml(0-2): 568, 18570, 40601, 18714, 539
https://tests.stockfishchess.org/tests/view/68b750518f94a4e5a7fe76cd

Passed Non-regression LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 335232 W: 85443 L: 85543 D: 164246
Ptnml(0-2): 177, 36616, 94137, 36502, 184
https://tests.stockfishchess.org/tests/view/68bc767259efc3c96b61076b

closes https://github.com/official-stockfish/Stockfish/pull/6303

Bench: 2213844
2025-09-28 21:12:01 +02:00
7a36c0e95f Remove quiet move streak
Passed Non-regression STC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 67712 W: 17744 L: 17555 D: 32413
Ptnml(0-2): 204, 8030, 17274, 8069, 279
https://tests.stockfishchess.org/tests/view/68b784628f94a4e5a7fe7706

Passed Non-regression LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 196050 W: 50270 L: 50228 D: 95552
Ptnml(0-2): 122, 21465, 54813, 21499, 126
https://tests.stockfishchess.org/tests/view/68ba119d8f94a4e5a7fe7941

closes https://github.com/official-stockfish/Stockfish/pull/6299

Bench: 2238789

Co-authored-by: Daniel Monroe <github.com@danielmonroe.net>
2025-09-28 21:08:58 +02:00
Michael ChalyandJoost VandeVondele 4f4f78f86e Extend nodes pre qsearch only with deep enough tt entries
Modification of current pre qsearch extensions - allowing it only for deep enough tt entries.

Passed STC:
https://tests.stockfishchess.org/tests/view/68c954d302c43c969fe7eea5
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 35872 W: 9548 L: 9236 D: 17088
Ptnml(0-2): 101, 4075, 9295, 4341, 124

Passed LTC:
https://tests.stockfishchess.org/tests/view/68ca4e4f02c43c969fe7ef5f
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 107754 W: 27784 L: 27324 D: 52646
Ptnml(0-2): 47, 11528, 30300, 11922, 80

closes https://github.com/official-stockfish/Stockfish/pull/6324

bench: 2462792
2025-09-28 20:56:36 +02:00
Nonlinear2andJoost VandeVondele 6fa42d9724 Simplify RFP return value
Passed non-regression STC:
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 220800 W: 57351 L: 57332 D: 106117
Ptnml(0-2): 726, 26200, 56548, 26181, 745
https://tests.stockfishchess.org/tests/view/68b1db6e6217b8721dca9c67

Passed gainer LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 257820 W: 66286 L: 65523 D: 126011
Ptnml(0-2): 118, 27586, 72779, 28269, 158
https://tests.stockfishchess.org/tests/view/68c1d40859efc3c96b610e3d

closes https://github.com/official-stockfish/Stockfish/pull/6310

bench: 2364596
2025-09-28 20:53:47 +02:00