75edbee01e
Use huge pages for worker data
...
As the worker data is quite large (28MB after #6350 ) we can make use of huge pages as a speedup.
prior to #6350
STC passed elo gaining bounds:
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 166272 W: 43479 L: 42993 D: 79800
Ptnml(0-2): 540, 17598, 46365, 18102, 531
https://tests.stockfishchess.org/tests/view/68e9f3c0d323fd15c04e3ba4
Tested the speedup on a large machine with speedtest:
==== master ====
Average (over 20): 288644510
==== largePageWorker ====
Average (over 20): 292082422
Test after #6350 :
==== rustam-cpp-testPR ====
Average (over 20): 291035351
==== rustam-cpp-testPR-pages ====
Average (over 20): 291937367
https://github.com/official-stockfish/Stockfish/pull/6359
No functional change
2025-10-14 17:46:13 +02:00
315f8ba4bf
let CI check for mate scores outside the valid range
...
closes https://github.com/official-stockfish/Stockfish/pull/6358
No functional change
2025-10-14 17:34:17 +02:00
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
63d449d1d9
bigger PAWN_HISTORY_SIZE
...
STC (10+0.1 th1) was accepted:
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 75712 W: 19701 L: 19326 D: 36685
Ptnml(0-2): 254, 8738, 19513, 9081, 270
https://tests.stockfishchess.org/tests/view/68e286d5fa806e2e8393d160
LTC (60+0.6 th1) was accepted:
LLR: 2.96 (-2.94,2.94) <0.50,2.50>
Total: 108492 W: 28068 L: 27604 D: 52820
Ptnml(0-2): 60, 11639, 30390, 12091, 66
https://tests.stockfishchess.org/tests/view/68e3e564a017f472e763dac0
closes https://github.com/official-stockfish/Stockfish/pull/6350
bench 2128316
2025-10-14 17:27:42 +02:00
c956df4cbb
Split accumulator 3-way for avxvnni
...
This does the same thing for x86-64-avxvnni as #6336 , #6339 .
closes https://github.com/official-stockfish/Stockfish/pull/6347
No functional change
2025-10-14 17:25:48 +02:00
fc5d296f9d
Update get_native_properties.sh for AVXVNNI
...
Update get_native_properties.sh to detect and report 'x86-64-avxvnni' when the CPU supports it.
closes https://github.com/official-stockfish/Stockfish/pull/6346
No functional change
2025-10-14 17:22:30 +02:00
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
feb17e5acf
Make sure we don't move a nonexistent piece in SEE
...
added assert.
closes https://github.com/official-stockfish/Stockfish/pull/6342
No functional change
2025-10-07 11:49:00 +02:00
ee243f0fdc
Remove x86-64-vnni256 target
...
When vnni256 was first introduced #3038 it was very slightly faster than vnni512
on some machines. We have since sped up vnni512 significantly (#4796 over 10%
alone, #6139 , and probably others I'm forgetting). Since any machine that can
run vnni256 can run vnni512 this arch is no longer useful.
Note, x86-64-avxvnni still covers targets that don't have AVX512 but do have
VNNI on 128- and 256-bit vectors.
closes https://github.com/official-stockfish/Stockfish/pull/6340
No functional change
2025-10-05 09:38:44 +02:00
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
b09339a420
Split accumulator 3-Way
...
Squeeze a tiny bit more juice from the original idea in #6336 which this is on top of.
https://tests.stockfishchess.org/tests/view/68dddd85fa806e2e8393c0b9
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 156320 W: 40925 L: 40447 D: 74948
Ptnml(0-2): 427, 17330, 42172, 17800, 431
4-way doesn't look to be better than this.
https://tests.stockfishchess.org/tests/view/68dde19efa806e2e8393c0c1
closes https://github.com/official-stockfish/Stockfish/pull/6339
No functional change
Co-authored-by: M Stembera <m_stembera@yahoo.com >
2025-10-05 09:33:23 +02:00
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
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
5895f47dab
Further simplify low ply history in evasions
...
Passed Non-regression STC (vs #6308 ):
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 174208 W: 45414 L: 45343 D: 83451
Ptnml(0-2): 633, 20324, 45095, 20443, 609
https://tests.stockfishchess.org/tests/view/68c24be359efc3c96b611487
Passed Non-regression LTC (vs #6308 ):
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 110070 W: 28099 L: 27969 D: 54002
Ptnml(0-2): 56, 11919, 30962, 12035, 63
https://tests.stockfishchess.org/tests/view/68c4efa559efc3c96b611dfc
closes https://github.com/official-stockfish/Stockfish/pull/6321
Bench: 2151873
2025-10-05 09:18:16 +02:00
3073d82ccf
Simplify use of low-ply history in evasions
...
Passed Non-regression STC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 65024 W: 16991 L: 16804 D: 31229
Ptnml(0-2): 182, 7423, 17119, 7602, 186
https://tests.stockfishchess.org/tests/view/68c23f5459efc3c96b6113df
Passed Non-regression LTC:
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 207312 W: 53126 L: 53095 D: 101091
Ptnml(0-2): 126, 21986, 59389, 22041, 114
https://tests.stockfishchess.org/tests/view/68c241e359efc3c96b6113ef
closes https://github.com/official-stockfish/Stockfish/pull/6308
Bench: 2515619
2025-09-28 21:21:57 +02:00
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
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
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
9b164d9520
Shave some instructions off a hot loop in affine transform
...
On x86, GCC generates highly suboptimal code for this loop in its old form,
about 2x as many instructions as necessary. This decreases throughput
especially in an SMT setting. Clang does a better job but this change still has
some improvement. Note that the std::ptrdiff_t type is not optional; using an
unsigned type brings back the bad assembly. (Not sure why, but it seems
reliable on all the GCC versions I tested.)
passed STC:
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 44672 W: 11841 L: 11527 D: 21304
Ptnml(0-2): 165, 4625, 12415, 4993, 138
https://tests.stockfishchess.org/tests/view/68d8111efa806e2e8393b10e
closes https://github.com/official-stockfish/Stockfish/pull/6331
No functional change
2025-09-28 21:04:29 +02:00
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
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
bbad001a49
Double PawnHistory size and update formula
...
Doubling PAWN_HISTORY_SIZE to 1024. So with that, we can apply a stronger learning signal.
The bonus/malus multipliers in the update_quiet_histories function have been increased accordingly.
Passed STC:
LLR: 2.97 (-2.94,2.94) <0.00,2.00>
Total: 111008 W: 29136 L: 28708 D: 53164
Ptnml(0-2): 367, 12870, 28609, 13284, 374
https://tests.stockfishchess.org/tests/view/68c201d659efc3c96b61117e
Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 117210 W: 30142 L: 29664 D: 57404
Ptnml(0-2): 49, 12532, 32970, 13000, 54
https://tests.stockfishchess.org/tests/view/68c20a6259efc3c96b6111ef
closes https://github.com/official-stockfish/Stockfish/pull/6306
Bench: 2788334
2025-09-28 20:51:34 +02:00
a47a1c1804
Penalty to TT move history on MultiCut
...
If a reduced search fails high with the TT move excluded, we know that
there are multiple moves that can produce cutoffs. Applying a penalty
to the TT move history reduces extensions for TT moves so that it may
spend a bit more time exploring other moves.
Passed STC:
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 263680 W: 68965 L: 68313 D: 126402
Ptnml(0-2): 855, 31090, 67336, 31666, 893
https://tests.stockfishchess.org/tests/view/68c1f65a59efc3c96b6110e5
Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 61008 W: 15713 L: 15350 D: 29945
Ptnml(0-2): 27, 6428, 17235, 6783, 31
https://tests.stockfishchess.org/tests/view/68c1fc5359efc3c96b611141
Passed non-regression VLTC (60+0.6, Threads=8):
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 50340 W: 13003 L: 12830 D: 24507
Ptnml(0-2): 3, 4570, 15849, 4747, 1
https://tests.stockfishchess.org/tests/view/68c2056559efc3c96b6111c3
closes https://github.com/official-stockfish/Stockfish/pull/6305
Bench: 2342975
2025-09-28 20:49:24 +02:00
a82e2a4cb6
Replace deprecated macOS 13 runner image
...
The macOS 13 runner image will be retired by December 4th, 2025.
closes https://github.com/official-stockfish/Stockfish/pull/6330
No functional change
2025-09-28 20:46:42 +02:00
f922fb5d55
add multithreaded matetrack runs to CI
...
Add runs with --threads 4 to our matetrack CI. These won't be deterministic, of
course. But they may catch early some multithreading bugs in our mate
reporting.
Motivated by #6293 and #6296 .
https://github.com/official-stockfish/Stockfish/pull/6297
No functional change.
2025-09-28 20:45:30 +02:00
1a3a9c9005
simplify upload_binaries ci
...
Previously the upload step used the os of the artifact to create the upload and
used an extra msys2 step. This is in fact not needed and we can do all required
changes on ubuntu instead.
closes https://github.com/official-stockfish/Stockfish/pull/6294
No functional change
2025-09-28 20:43:54 +02:00
fc54d87301
Revert "Adjustment of the aspiration window after fail high/low."
...
This reverts commit bfc7000597https://github.com/official-stockfish/Stockfish/issues/6296
After this commit a bug has been reported when the position is close to
mate or being mated. Since no workarounds have been suggested yet, it
is best to revert this commit until a better solution is found.
closes https://github.com/official-stockfish/Stockfish/pull/6309
Bench: 2493363
2025-09-13 08:18:52 +02:00
bfc7000597
Adjustment of the aspiration window after fail high/low.
...
For the new bound in the opposite direction of the fail, use a weighted average of alpha, beta and best value +- delta. In the case of a fail high, different average weights are used depending on whether or not there was a best move change during the last search.
The weights are determined from the following two consecutive LTC tunings.
First tuning: https://tests.stockfishchess.org/tests/view/68ab727975da51a345a5ac2e
Second tuning: https://tests.stockfishchess.org/tests/view/68aba3fe75da51a345a5ad52
Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 39504 W: 10243 L: 9947 D: 19314
Ptnml(0-2): 25, 4182, 11041, 4480, 24
https://tests.stockfishchess.org/tests/view/68acbb6d6217b8721dca95f8
Passed VLTC:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 91196 W: 23574 L: 23167 D: 44455
Ptnml(0-2): 13, 8943, 27276, 9356, 10
https://tests.stockfishchess.org/tests/view/68af64786217b8721dca993d
closes https://github.com/official-stockfish/Stockfish/pull/6292
Bench: 2785713
2025-09-06 07:57:57 +02:00
d5f152b5df
Reintroduce #6259
...
Reintroduces af181d9#6286
Using ./stockfish on matetrack.epd with --nodes 1000000
Engine ID: Stockfish dev-20250902-adfddd2c
Total FENs: 6554
Found mates: 3490
Best mates: 2429
Passed Non-regression LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 37608 W: 9726 L: 9523 D: 18359
Ptnml(0-2): 16, 4001, 10578, 4182, 27
https://tests.stockfishchess.org/tests/view/68b886778f94a4e5a7fe77d9
closes https://github.com/official-stockfish/Stockfish/pull/6289
Bench: 2493363
2025-09-06 07:55:14 +02:00
adfddd2c98
Add scaling note to STC/LTC tunes
...
It has been repeatedly shown that such tunes are suspectible to become
anti-scaling. Below are some recent examples:
https://github.com/official-stockfish/Stockfish/commit/2e91a8635468e40c89a2303ce50384864d088611
https://github.com/official-stockfish/Stockfish/commit/d11f49b790429c236a1a4169f0d8052635fc03dc
Passed STC:
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 32448 W: 8651 L: 8342 D: 15455
Ptnml(0-2): 81, 3695, 8408, 3914, 126
https://tests.stockfishchess.org/tests/view/6899489b0049e8ccef9d64ad
Passed LTC:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 73854 W: 19042 L: 18649 D: 36163
Ptnml(0-2): 37, 7908, 20659, 8271, 52
https://tests.stockfishchess.org/tests/view/689abbe7fd8719b088c8d514
Revert VVLTC with STC bound:
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 53802 W: 14030 L: 13740 D: 26032
Ptnml(0-2): 5, 4924, 16754, 5212, 6
https://tests.stockfishchess.org/tests/view/68a9a9f575da51a345a5a675
Revert VVLTC with LTC bound:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 53658 W: 14022 L: 13699 D: 25937
Ptnml(0-2): 3, 4894, 16712, 5217, 3
https://tests.stockfishchess.org/tests/view/68a8d2b2b6fb3300203bca77
https://tests.stockfishchess.org/tests/view/688cf38bf17748b4d23c8057
https://tests.stockfishchess.org/tests/view/6890bc7792fcad741b804a19
Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 74928 W: 19466 L: 19071 D: 36391
Ptnml(0-2): 37, 8048, 20901, 8439, 39
Failed Non-regression VLTC:
LLR: -2.94 (-2.94,2.94) <-1.75,0.25>
Total: 57704 W: 14643 L: 14928 D: 28133
Ptnml(0-2): 5, 5925, 17280, 5634, 8
https://tests.stockfishchess.org/tests/view/6890bc7792fcad741b804a19
(Note that an STC-tuned version passed non-regression, but was shortly
simplified)
https://github.com/official-stockfish/Stockfish/pull/6040
Passed STC:
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 27776 W: 7352 L: 7054 D: 13370
Ptnml(0-2): 68, 3126, 7221, 3386, 87
https://tests.stockfishchess.org/tests/view/680ec0f83629b02d74b1605b
Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 161304 W: 41432 L: 40864 D: 79008
Ptnml(0-2): 61, 17305, 45357, 17863, 66
https://tests.stockfishchess.org/tests/view/680ec7f93629b02d74b16084
Failed Non-regression VVLTC:
LLR: -2.94 (-2.94,2.94) <-1.75,0.25>
Total: 313466 W: 80573 L: 81089 D: 151804
Ptnml(0-2): 38, 29689, 97782, 29199, 25
https://tests.stockfishchess.org/tests/view/6810d0533629b02d74b16756
https://github.com/official-stockfish/Stockfish/pull/5907
https://github.com/official-stockfish/Stockfish/pull/5887
Passed LTC with STC bounds:
https://tests.stockfishchess.org/tests/view/67b115dd6c6b9e172ad1592f
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 75756 W: 19393 L: 19044 D: 37319
Ptnml(0-2): 60, 8251, 20913, 8588, 66
Passed LTC with LTC bounds:
https://tests.stockfishchess.org/tests/view/67af5f5d6c6b9e172ad15765
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 108126 W: 27880 L: 27412 D: 52834
Ptnml(0-2): 85, 11786, 29866, 12228, 98
Revert VVLTC w/ STC bounds:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 56342 W: 14536 L: 14246 D: 27560
Ptnml(0-2): 7, 5061, 17741, 5359, 3
https://tests.stockfishchess.org/tests/view/67be4f8ad8d5c2c657c52d10
Revert VVLTC w/ LTC bounds:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 66562 W: 17364 L: 17016 D: 32182
Ptnml(0-2): 3, 6145, 20637, 6493, 3
https://tests.stockfishchess.org/tests/view/67bcd25ff6b602bd7222ea40
closes https://github.com/official-stockfish/Stockfish/pull/6284
no functional change
2025-09-02 20:42:03 +02:00
f2da0ccf3f
Simplify SMP Reduction
...
Passed Non-regression SMP STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 232784 W: 59845 L: 59841 D: 113098
Ptnml(0-2): 289, 26459, 62934, 26379, 331
https://tests.stockfishchess.org/tests/view/68ab96bf75da51a345a5acd6
Passed Non-regression SMP LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 374270 W: 95978 L: 96113 D: 182179
Ptnml(0-2): 118, 38575, 109888, 38432, 122
https://tests.stockfishchess.org/tests/view/68abcf1c75da51a345a5adb6
closes https://github.com/official-stockfish/Stockfish/pull/6285
Bench: 2667107
2025-09-02 20:41:08 +02:00
75ac6c7a06
simplify stalemate further
...
Non-regression STC:
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 155200 W: 40650 L: 40562 D: 73988
Ptnml(0-2): 533, 17588, 41258, 17700, 521
https://tests.stockfishchess.org/tests/view/68abe11375da51a345a5adec
Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 82824 W: 21442 L: 21287 D: 40095
Ptnml(0-2): 51, 8738, 23675, 8901, 47
https://tests.stockfishchess.org/tests/view/68b205606217b8721dca9c8e
10k Stalemate:
Elo: 1.46 ± 1.2 (95%) LOS: 99.0%
Total: 10000 W: 4640 L: 4598 D: 762
Ptnml(0-2): 0, 140, 4678, 182, 0
https://tests.stockfishchess.org/tests/view/68b2059b6217b8721dca9c90
closes https://github.com/official-stockfish/Stockfish/pull/6283
Bench: 2431727
2025-09-02 20:39:02 +02:00
da63060ea3
Simplify sign term in quiet histories
...
Simplify sign term in quiet histories
Passed simplification STC
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 497824 W: 129130 L: 129418 D: 239276
Ptnml(0-2): 1546, 59040, 128008, 58792, 1526
https://tests.stockfishchess.org/tests/view/68a2a9c1b6fb3300203bc3ed
Passed simplification LTC
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 70830 W: 18185 L: 18016 D: 34629
Ptnml(0-2): 36, 7658, 19861, 7821, 39
https://tests.stockfishchess.org/tests/view/68af36c96217b8721dca98d9
closes https://github.com/official-stockfish/Stockfish/pull/6282
Bench: 2393762
2025-09-02 20:37:04 +02:00
3833583862
limit dynamic reduction.
...
fixes https://github.com/official-stockfish/Stockfish/issues/6280
prevents probcut from extending depth as analyzed here:
https://github.com/official-stockfish/Stockfish/pull/6254#issuecomment-3239144280
passed STC:
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 86688 W: 22591 L: 22426 D: 41671
Ptnml(0-2): 305, 10125, 22311, 10306, 297
https://tests.stockfishchess.org/tests/view/68b418ab467ff96994ae4cd5
passed LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 82914 W: 21287 L: 21130 D: 40497
Ptnml(0-2): 39, 8959, 23305, 9114, 40
https://tests.stockfishchess.org/tests/view/68b47ffa78ed7a752a9e8f36
closes https://github.com/official-stockfish/Stockfish/pull/6286
Bench: 2787731
Co-Authored-By: xu-shawn <50402888+xu-shawn@users.noreply.github.com >
2025-09-02 20:34:47 +02:00
731ad9bbc3
Simplify adjust_key50 template
...
Remove the AfterMove template from the adjust_key50 function, which is only ever called with false.
closes https://github.com/official-stockfish/Stockfish/pull/6278
No functional change
2025-08-30 15:17:57 +02:00
7a3483fa9e
Remove superfluous cast
...
closes https://github.com/official-stockfish/Stockfish/pull/6277
No functional change
2025-08-30 15:14:51 +02:00
6a6dadb5a6
Remove buggy and unused function
...
The function does not fulfill its purpose and is not used anywhere.
See https://discord.com/channels/435943710472011776/1101022188313772083/1409801409855094874
closes https://github.com/official-stockfish/Stockfish/pull/6275
no functional change
2025-08-30 15:13:40 +02:00
3f18352396
Further Simplify Stalemate Detection
...
Passed Non-regression STC:
LLR: 2.98 (-2.94,2.94) <-1.75,0.25>
Total: 191520 W: 49633 L: 49582 D: 92305
Ptnml(0-2): 557, 20676, 53260, 20693, 574
https://tests.stockfishchess.org/tests/view/68ab570075da51a345a5abe1
Passed Non-regression LTC:
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 212934 W: 54643 L: 54618 D: 103673
Ptnml(0-2): 117, 22417, 61364, 22462, 107
https://tests.stockfishchess.org/tests/view/68ab84e975da51a345a5ac6b
10k Stalemate:
Elo: 0.35 ± 1.2 (95%) LOS: 71.6%
Total: 10000 W: 4602 L: 4592 D: 806
Ptnml(0-2): 0, 148, 4694, 158, 0
nElo: 1.99 ± 6.8 (95%) PairsRatio: 1.07
https://tests.stockfishchess.org/tests/view/68abeb8175da51a345a5af82
closes https://github.com/official-stockfish/Stockfish/pull/6268
Bench: 2420973
2025-08-30 15:12:06 +02:00
7d213afd37
Non-functional simplifications
...
closes https://github.com/official-stockfish/Stockfish/pull/6267
No functional change
Co-authored-by: Daniel Monroe <github.com@danielmonroe.net >
2025-08-30 15:09:47 +02:00
a289ee389a
Simplify Capture Futility Pruning
...
Passed Non-regression STC:
LLR: 2.97 (-2.94,2.94) <-1.75,0.25>
Total: 187904 W: 48639 L: 48583 D: 90682
Ptnml(0-2): 560, 22150, 48502, 22154, 586
https://tests.stockfishchess.org/tests/view/68aad56075da51a345a5a9e3
Passed Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 94302 W: 24246 L: 24101 D: 45955
Ptnml(0-2): 44, 10274, 26371, 10417, 45
https://tests.stockfishchess.org/tests/view/68ab541975da51a345a5aacf
closes https://github.com/official-stockfish/Stockfish/pull/6266
Bench: 2376717
2025-08-30 15:09:00 +02:00
222df615c1
revert #6259
...
The recent commit af181d9https://github.com/vondele/matetrack/blob/69f5c5e8627c163a6a8480b869ee09bc44dc44d4/matetrack1000000.csv#L4075-L4076
So this PR proposes to revert it, while adding a comment in the code for future reference.
closes https://github.com/official-stockfish/Stockfish/pull/6269
Bench: 2566711
2025-08-30 15:06:57 +02:00
75f07da912
Avoid high rule50 count zeroing cutoffs
...
If the depth is low enough, don't TT cut if the rule50 count is high and the TT move is zeroing.
Passed STC:
https://tests.stockfishchess.org/tests/view/68a8fdd8b6fb3300203bcb92
LLR: 3.05 (-2.94,2.94) <0.00,2.00>
Total: 110304 W: 28805 L: 28402 D: 53097
Ptnml(0-2): 275, 11174, 31875, 11529, 299
Passed LTC:
https://tests.stockfishchess.org/tests/view/68aa200f75da51a345a5a809
LLR: 3.00 (-2.94,2.94) <0.50,2.50>
Total: 187956 W: 48489 L: 47928 D: 91539
Ptnml(0-2): 59, 16118, 61075, 16655, 71
closes https://github.com/official-stockfish/Stockfish/pull/6271
bench: 2641840
2025-08-30 15:05:11 +02:00
69de394439
fix ppc altivec check & loongarch64-lsx typo
...
closes https://github.com/official-stockfish/Stockfish/pull/6276
No functional change
2025-08-30 15:03:09 +02:00
cb7232a818
Use integer type for UCI spin values
...
In particular, parse spin values as integers to avoid rounding errors.
Fixes https://github.com/official-stockfish/Stockfish/issues/6263
closes https://github.com/official-stockfish/Stockfish/pull/6264
No functional change
2025-08-30 15:02:05 +02:00
678d503d8f
Simplify LMR Extensions
...
Passed Non-regression STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 236896 W: 61683 L: 61683 D: 113530
Ptnml(0-2): 730, 28057, 60901, 28003, 757
https://tests.stockfishchess.org/tests/view/68a9c20475da51a345a5a6a0
Passed Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 73644 W: 18936 L: 18770 D: 35938
Ptnml(0-2): 33, 7951, 20685, 8123, 30
https://tests.stockfishchess.org/tests/view/68aa95c575da51a345a5a88a
closes https://github.com/official-stockfish/Stockfish/pull/6265
Bench: 2693376
2025-08-24 20:10:43 +02:00
39c077f15a
Less reduction for later threads.
...
Give "(thread id mod 8) * 64" less reductions (up to nearly a half ply).
Passed SMP STC:
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 413176 W: 106496 L: 105666 D: 201014
Ptnml(0-2): 504, 46732, 111266, 47602, 484
https://tests.stockfishchess.org/tests/view/68a24aeeb6fb3300203bbdc4
Passed SMP LTC:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 60420 W: 15622 L: 15268 D: 29530
Ptnml(0-2): 11, 6106, 17632, 6440, 21
https://tests.stockfishchess.org/tests/view/68a2c2ffb6fb3300203bc516
closes https://github.com/official-stockfish/Stockfish/pull/6249
No functional change
2025-08-24 20:07:50 +02:00
c99eb8ef32
Remove cap from a bonusScale formula
...
Passed STC:
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 127264 W: 33159 L: 33042 D: 61063
Ptnml(0-2): 336, 14509, 33866, 14544, 377
https://tests.stockfishchess.org/tests/view/68a63fccb6fb3300203bc818
Passed LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 469512 W: 120094 L: 120331 D: 229087
Ptnml(0-2): 238, 51317, 131885, 51076, 240
https://tests.stockfishchess.org/tests/view/68a8d867b6fb3300203bcab5
closes https://github.com/official-stockfish/Stockfish/pull/6260
Bench: 2433974
2025-08-24 20:01:01 +02:00
af181d9fe1
Small simplification in probCut movepicker
...
Remove no longer required condition for tt moves. The idea is that if tt the value is
greater than probCut beta try tt move that is a capture anyway - even if it
doesn't pass SEE check. This idea in various implementations passed some STCs
and was looking decent at LTCs as a gainer.
Passed STC:
https://tests.stockfishchess.org/tests/view/68aa1ee075da51a345a5a805
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 136160 W: 35189 L: 35079 D: 65892
Ptnml(0-2): 436, 16083, 34891, 16275, 395
Passed LTC:
https://tests.stockfishchess.org/tests/view/68aa91d375da51a345a5a884
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 80022 W: 20652 L: 20492 D: 38878
Ptnml(0-2): 33, 8717, 22357, 8865, 39
closes https://github.com/official-stockfish/Stockfish/pull/6259
Bench: 2307940
2025-08-24 19:58:49 +02:00
e2fdf6f005
Simplify separate malus formulas
...
Passed Non-regression STC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 16352 W: 4336 L: 4090 D: 7926
Ptnml(0-2): 54, 1832, 4157, 2080, 53
https://tests.stockfishchess.org/tests/view/68a808f0b6fb3300203bca08
Passed Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 94014 W: 24129 L: 23986 D: 45899
Ptnml(0-2): 47, 9917, 26934, 10064, 45
https://tests.stockfishchess.org/tests/view/68a8f45cb6fb3300203bcb5e
closes https://github.com/official-stockfish/Stockfish/pull/6256
Bench: 2483704
2025-08-24 19:55:35 +02:00
Kieren Pearson
Robert Nurnberg @ elitebook
Daniel Monroe
rustam-cpp
mstembera
dav1312
Daniel Samek
Shawn Xu
Timothy Herchen
FauziAkram
nicolasduhamel
Michael Chaly
Nonlinear2
Syine Mineta
Sebastian Buchwald
Disservin
Stefan Geschwentner
Joost VandeVondele
Arseniy Surkov
Torsten Hellwig
Akshat Sinha