Stockfish Development Versions are build automatically if there are changes on the master branch in the git repository (https://github.com/official-stockfish/Stockfish). Use it at your own risk.
They are compiled with gcc 11.2/mingw 10 on Ubuntu 22.04.

Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Disservin
Date: Mon Sep 9 17:21:14 2024 +0200
Timestamp: 1725895274

Restore development

closes https://github.com/official-stockfish/Stockfish/pull/5580

No functional change
see source
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Joost VandeVondele
Date: Fri Sep 6 16:53:45 2024 +0200
Timestamp: 1725634425

Stockfish 17

Official release version of Stockfish 17

Bench: 1484730

---

Stockfish 17

Today we have the pleasure to announce a new major release of Stockfish. As
always, you can freely download it at https://stockfishchess.org/download and
use it in the GUI of your choice.

Don’t forget to join our Discord server[1] to get in touch with the community
of developers and users of the project!

*Quality of chess play*

In tests against Stockfish 16, this release brings an Elo gain of up to 46
points[2] and wins up to 4.5 times more game pairs[3] than it loses. In
practice, high-quality moves are now found in less time, with a user upgrading
from Stockfish 14 being able to analyze games at least 6 times[4] faster with
Stockfish 17 while maintaining roughly the same quality.

During this development period, Stockfish won its 9th consecutive first place
in the main league of the Top Chess Engine Championship (TCEC)[5], and the 24th
consecutive first place in the main events (bullet, blitz, and rapid) of the
Computer Chess Championship (CCC)[6].

*Update highlights*

*Improved engine lines*

This release introduces principal variations (PVs) that are more informative
for mate and decisive table base (TB) scores. In both cases, the PV will
contain all moves up to checkmate. For mate scores, the PV shown is the best
variation known to the engine at that point, while for table base wins, it
follows, based on the TB, a sequence of moves that preserves the game outcome
to checkmate.

*NUMA performance optimization*

For high-end computers with multiple CPUs (typically a dual-socket architecture
with 100+ cores), this release automatically improves performance with a
`NumaPolicy` setting that optimizes non-uniform memory access (NUMA). Although
typical consumer hardware will not benefit, speedups of up to 2.8x[7] have been
measured.

*Shoutouts*

*ChessDB*

During the past 1.5 years, hundreds of cores have been continuously running
Stockfish to grow a database of analyzed positions. This chess cloud
database[8] now contains well over 45 billion positions, providing excellent
coverage of all openings and commonly played lines. This database is already
integrated into GUIs such as En Croissant[9] and Nibbler[10], which access it
through the public API.

*Leela Chess Zero*

Generally considered to be the strongest GPU engine, it continues to provide
open data which is essential for training our NNUE networks. They released
version 0.31.1[11] of their engine a few weeks ago, check it out!

*Website redesign*

Our website has undergone a redesign in recent months, most notably in our home
page[12], now featuring a darker color scheme and a more modern aesthetic,
while still maintaining its core identity. We hope you'll like it as much as we
do!

*Thank you*

The Stockfish project builds on a thriving community of enthusiasts (thanks
everybody!) who contribute their expertise, time, and resources to build a free
and open-source chess engine that is robust, widely available, and very strong.

We would like to express our gratitude for the 11k stars[13] that light up our
GitHub project! Thank you for your support and encouragement – your recognition
means a lot to us.

We invite our chess fans to join the Fishtest testing framework[14] to
contribute compute resources needed for development. Programmers can contribute
to the project either directly to Stockfish[15] (C++), to Fishtest[16] (HTML,
CSS, JavaScript, and Python), to our trainer nnue-pytorch[17] (C++ and Python),
or to our website[18] (HTML, CSS/SCSS, and JavaScript).

The Stockfish team

[1] https://discord.gg/GWDRS3kU6R
[2] https://tests.stockfishchess.org/tests/view/66d738ba9de3e7f9b33d159a
[3] https://tests.stockfishchess.org/tests/view/66d738f39de3e7f9b33d15a0
[4] https://github.com/official-stockfish/Stockfish/wiki/Useful-data#equivalent-time-odds-and-normalized-game-pair-elo
[5] https://en.wikipedia.org/wiki/Stockfish_(chess)#Top_Chess_Engine_Championship
[6] https://en.wikipedia.org/wiki/Stockfish_(chess)#Chess.com_Computer_Chess_Championship
[7] https://github.com/official-stockfish/Stockfish/pull/5285
[8] https://chessdb.cn/queryc_en/
[9] https://encroissant.org/
[10] https://github.com/rooklift/nibbler
[11] https://github.com/LeelaChessZero/lc0/releases/tag/v0.31.1
[12] https://stockfishchess.org/
[13] https://github.com/official-stockfish/Stockfish/stargazers
[14] https://github.com/official-stockfish/fishtest/wiki/Running-the-worker
[15] https://github.com/official-stockfish/Stockfish
[16] https://github.com/official-stockfish/fishtest
[17] https://github.com/official-stockfish/nnue-pytorch
[18] https://github.com/official-stockfish/stockfish-web
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Joost VandeVondele
Date: Tue Sep 3 17:53:23 2024 +0200
Timestamp: 1725378803

Update Top CPU Contributors

to the status as of Aug 31st 2024.

closes https://github.com/official-stockfish/Stockfish/pull/5561

No functional change
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers
Windows x64 + SSSE3
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Robert Nurnberg @ elitebook
Date: Tue Sep 3 17:53:23 2024 +0200
Timestamp: 1725378803

Update the WDL model

updates the internal WDL model, using data from 2.6M games played by the revisions since 9fb5832.

https://github.com/official-stockfish/Stockfish/pull/5565

No functional change
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Joost VandeVondele
Date: Tue Sep 3 17:48:58 2024 +0200
Timestamp: 1725378538

Fix some of the tests

due to https://github.com/official-stockfish/Stockfish/issues/5185 some CI tests are skipped.
This patch fixes a few tests that need updating.

closes https://github.com/official-stockfish/Stockfish/pull/5560

No functional change
see source
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: FauziAkram
Date: Wed Aug 28 09:35:21 2024 +0200
Timestamp: 1724830521

Simpler formula for ss->cutoffCnt update

closes https://github.com/official-stockfish/Stockfish/pull/5548

No functional change
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Taras Vuk
Date: Wed Aug 28 09:34:09 2024 +0200
Timestamp: 1724830449

rename !(PvNode || cutNode) to allNode

Passed STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 108992 W: 28178 L: 28039 D: 52775 Elo +0.44
Ptnml(0-2): 356, 12428, 28762, 12621, 329
https://tests.stockfishchess.org/tests/view/66c73a51bf8c9d8780fda532

closes https://github.com/official-stockfish/Stockfish/pull/5549

No functional change
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Tomasz Sobczyk
Date: Wed Aug 28 08:52:24 2024 +0200
Timestamp: 1724827944

Forcibly split NUMA nodes on Windows

split by processor groups due to Window's thread scheduler issues.

fixes #5551
closes https://github.com/official-stockfish/Stockfish/pull/5552

No functional change
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Taras Vuk
Date: Tue Aug 20 21:37:25 2024 +0200
Timestamp: 1724182645

Tweak late move extensions

Allow late move extensions only for PV and cut nodes.

Passed STC:
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 44512 W: 11688 L: 11355 D: 21469 Elo +2.60
Ptnml(0-2): 167, 5180, 11229, 5513, 167
https://tests.stockfishchess.org/tests/view/66c0509d4ff211be9d4ef10e

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 152970 W: 39026 L: 38466 D: 75478 Elo +1.27
Ptnml(0-2): 102, 16792, 42164, 17298, 129
https://tests.stockfishchess.org/tests/view/66c0994d21503a509c13b2b6

closes https://github.com/official-stockfish/Stockfish/pull/5541

bench: 1484730
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Shawn Xu
Date: Tue Aug 20 21:34:19 2024 +0200
Timestamp: 1724182459

Introduce Fail Low History Bonus

When a node fails low, give TT move a small bonus 1/4 of normal value.

Passed STC:
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 92384 W: 24094 L: 23691 D: 44599 Elo +1.52
Ptnml(0-2): 323, 10852, 23465, 11203, 349
https://tests.stockfishchess.org/tests/view/66be80794ff211be9d4eed68

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 114660 W: 29260 L: 28778 D: 56622 Elo +1.46
Ptnml(0-2): 97, 12506, 31653, 12966, 108
https://tests.stockfishchess.org/tests/view/66bf63ee4ff211be9d4eeef0

closes https://github.com/official-stockfish/Stockfish/pull/5539

bench 1463003
see source
Windows x64 for Haswell CPUs
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Nonlinear2
Date: Tue Aug 20 21:31:33 2024 +0200
Timestamp: 1724182293

Simplify stand pat adjustement

Remove && !PvNode condition for stand pat adjustement in quiescence search.

Passed non-regression STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 108544 W: 28228 L: 28085 D: 52231 Elo +0.46
Ptnml(0-2): 389, 12902, 27554, 13031, 396
https://tests.stockfishchess.org/tests/view/66bb402e4ff211be9d4ee688

Passed non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 193014 W: 48796 L: 48751 D: 95467 Elo +0.08
Ptnml(0-2): 188, 21481, 53116, 21542, 180
https://tests.stockfishchess.org/tests/view/66bc78774ff211be9d4ee88f

closes https://github.com/official-stockfish/Stockfish/pull/5538

Bench 1787360
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Shawn Xu
Date: Tue Aug 20 21:27:58 2024 +0200
Timestamp: 1724182078

Simplify doShallowerSearch

Passed Non-regression STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 242336 W: 62657 L: 62663 D: 117016 Elo -0.01
Ptnml(0-2): 941, 28949, 61418, 28895, 965
https://tests.stockfishchess.org/tests/view/66bc13c34ff211be9d4ee794

Passed Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 128100 W: 32503 L: 32390 D: 63207 Elo +0.31
Ptnml(0-2): 106, 14319, 35113, 14380, 132
https://tests.stockfishchess.org/tests/view/66bdbb304ff211be9d4eec5d

closes https://github.com/official-stockfish/Stockfish/pull/5537

bench 1586246
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Shawn Xu
Date: Tue Aug 20 21:24:04 2024 +0200
Timestamp: 1724181844

Simplify bestMove promotion

Passed Non-regression STC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 216768 W: 56240 L: 56217 D: 104311 Elo +0.04
Ptnml(0-2): 794, 24900, 56956, 24957, 777
https://tests.stockfishchess.org/tests/view/66bc11324ff211be9d4ee78b

Passed Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 44970 W: 11391 L: 11199 D: 22380 Elo +1.48
Ptnml(0-2): 44, 4596, 13002, 4810, 33
https://tests.stockfishchess.org/tests/view/66bdbb1b4ff211be9d4eec5a

closes https://github.com/official-stockfish/Stockfish/pull/5535

bench: 1613043
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Linmiao Xu
Date: Tue Aug 20 20:59:36 2024 +0200
Timestamp: 1724180376

Update default main net to nn-1111cefa1111.nnue

Created from 2 distinct spsa tunes of the latest main net (nn-31337bea577c.nnue)
and applying the params to the prior main net (nn-e8bac1c07a5a.nnue). This
effectively reverts the modifications to output weights and biases in
https://github.com/official-stockfish/Stockfish/pull/5509

SPSA:
A: 6000, alpha: 0.602, gamma: 0.101

1st - 437 feature transformer biases where values are < 25
54k / 120k games at 180+1.8
https://tests.stockfishchess.org/tests/view/66af98ac4ff211be9d4edad0
nn-808259761cca.nnue

2nd - 208 L2 weights where values are zero
112k / 120k games at 180+1.8
https://tests.stockfishchess.org/tests/view/66b0c3074ff211be9d4edbe5
nn-a56cb8c3d477.nnue

When creating the above 2 nets (nn-808259761cca.nnue, nn-a56cb8c3d477.nnue),
spsa params were unintentionally applied to nn-e8bac1c07a5a.nnue rather
than nn-31337bea577c.nnue due to an issue in a script that creates nets
by applying spsa results to base nets.

Since they both passed STC and were neutral or slightly positive at LTC,
they were combined to see if the elo from each set of params was additive.

The 2 nets can be merged on top of nn-e8bac1c07a5a.nnue with:
https://github.com/linrock/nnue-tools/blob/90942d3/spsa/combine_nnue.py
```
python3 combine_nnue.py \
nn-e8bac1c07a5a.nnue \
nn-808259761cca.nnue \
nn-a56cb8c3d477.nnue
```

Merging yields nn-87caa003fc6a.nnue which was renamed to nn-1111cefa1111.nnue
with an updated nnue-namer around 10x faster than before by:
- using a prefix trie for efficient prefix matches
- modifying 4 non-functional bytes near the end of the file instead of 2
https://github.com/linrock/nnue-namer

Thanks to @MinetaS for pointing out in #nnue-dev what the non-functional bytes are:
L3 is 32, 4 bytes for biases, 32 bytes for weights. (fc_2)
So -38 and -37 are technically -2 and -1 of fc_1 (type AffineTransform<30, 32>)
And since InputDimension is padded to 32 there are total 32 of 2 adjacent bytes padding.
So yes, it's non-functional whatever values are there.
It's possible to tweak bytes at -38 - 32 * N and -37 - 32 * N given N = 0 ... 31

The net renamed with the new method passed non-regression STC vs. the original net:
https://tests.stockfishchess.org/tests/view/66c0f0a821503a509c13b332

To print the spsa params with nnue-pytorch:
```
import features
from serialize import NNUEReader

feature_set = features.get_feature_set_from_name("HalfKAv2_hm")

with open("nn-31337bea577c.nnue", "rb") as f:
model = NNUEReader(f, feature_set).model

c_end = 16
for i,ft_bias in enumerate(model.input.bias.data[:3072]):
value = int(ft_bias * 254)
if abs(value) < 25:
print(f"ftB[{i}],{value},-1024,1024,{c_end},0.0020")

c_end = 6
for i in range(8):
for j in range(32):
for k in range(30):
value = int(model.layer_stacks.l2.weight.data[32 * i + j, k] * 64)
if value == 0:
print(f"twoW[{i}][{j}][{k}],{value},-127,127,{c_end},0.0020")
```

New params found with the same method as:
https://github.com/official-stockfish/Stockfish/pull/5459

Passed STC:
https://tests.stockfishchess.org/tests/view/66b4d4464ff211be9d4edf6e
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 136416 W: 35753 L: 35283 D: 65380 Elo +1.20
Ptnml(0-2): 510, 16159, 34416, 16597, 526

Passed LTC:
https://tests.stockfishchess.org/tests/view/66b76e814ff211be9d4ee1cc
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 159336 W: 40753 L: 40178 D: 78405 Elo +1.25
Ptnml(0-2): 126, 17497, 43864, 18038, 143

closes https://github.com/official-stockfish/Stockfish/pull/5534

bench 1613043
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: FauziAkram
Date: Tue Aug 20 20:57:07 2024 +0200
Timestamp: 1724180227

Simplify cutnode reduction formula

Passed STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 137994 W: 34705 L: 34603 D: 68686 Elo +0.26
Ptnml(0-2): 124, 15371, 37903, 15477, 122
https://tests.stockfishchess.org/tests/view/66aeb74b4ff211be9d4eda10

Passed LTC:
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 131456 W: 34148 L: 34031 D: 63277 Elo +0.31
Ptnml(0-2): 506, 15571, 33465, 15672, 514
https://tests.stockfishchess.org/tests/view/66ae258b4ff211be9d4ed95d

closes https://github.com/official-stockfish/Stockfish/pull/5531

Bench: 1261995
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Shawn Xu
Date: Tue Aug 20 20:51:39 2024 +0200
Timestamp: 1724179899

Simplify Post-LMR Continuation History Updates

Passed Non-regression STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 55520 W: 14625 L: 14420 D: 26475 Elo +1.28
Ptnml(0-2): 247, 6522, 14007, 6747, 237
https://tests.stockfishchess.org/tests/view/66ad40874ff211be9d4ed8f7

Passed Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 216168 W: 54561 L: 54540 D: 107067 Elo +0.03
Ptnml(0-2): 196, 24212, 59244, 24239, 193
https://tests.stockfishchess.org/tests/view/66aeac954ff211be9d4eda03

closes https://github.com/official-stockfish/Stockfish/pull/5530

bench 1418263
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Shawn Xu
Date: Tue Aug 20 20:47:46 2024 +0200
Timestamp: 1724179666

Improve Comments for Pairwise Multiplication Optimization

closes https://github.com/official-stockfish/Stockfish/pull/5524

no functional change
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Disservin
Date: Tue Aug 20 20:44:55 2024 +0200
Timestamp: 1724179495

Fix failing CI for MacOS 13 GCC 11

closes https://github.com/official-stockfish/Stockfish/pull/5540

No functional change
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Shawn Xu
Date: Sat Aug 3 09:42:54 2024 +0200
Timestamp: 1722670974

Simplify Cutnode Reduction

Passed Non-regression STC:
LR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 143968 W: 37439 L: 37333 D: 69196 Elo +0.26
Ptnml(0-2): 521, 17228, 36456, 17182, 597
https://tests.stockfishchess.org/tests/view/66a73f9f4ff211be9d4ed27f

Passed Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 198954 W: 50384 L: 50345 D: 98225 Elo +0.07
Ptnml(0-2): 201, 22360, 54347, 22337, 232
https://tests.stockfishchess.org/tests/view/66a906e94ff211be9d4ed423

closes https://github.com/official-stockfish/Stockfish/pull/5526

bench 1277466
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: MinetaS
Date: Sat Aug 3 09:42:03 2024 +0200
Timestamp: 1722670923

Move DotProd code into optimized affine layer

This patch moves the DotProd code into the propagation function which
has sequential access optimization. To prove the speedup, the comparison
is done without the sparse layer. With the sparse layer the effect is
marginal (GCC 0.3%, LLVM/Clang 0.1%).

For both tests, binary is compiled with GCC 14.1. Each test had 50 runs.

Sparse layer included:
```
speedup = +0.0030
P(speedup > 0) = 1.0000
```

Sparse layer excluded:
```
speedup = +0.0561
P(speedup > 0) = 1.0000
```

closes https://github.com/official-stockfish/Stockfish/pull/5520

No functional change
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Tomasz Sobczyk
Date: Sat Aug 3 09:41:37 2024 +0200
Timestamp: 1722670897

Replicate network weights only to used NUMA nodes

On a system with multiple NUMA nodes, this patch avoids unneeded replicated
(e.g. 8x for a single threaded run), reducting memory use in that case.

Lazy initialization forced before search.

Passed STC:
https://tests.stockfishchess.org/tests/view/66a28c524ff211be9d4ecdd4
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 691776 W: 179429 L: 179927 D: 332420 Elo -0.25
Ptnml(0-2): 2573, 79370, 182547, 78778, 2620

closes https://github.com/official-stockfish/Stockfish/pull/5515

No functional change
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Shawn Xu
Date: Sun Jul 28 22:22:50 2024 +0200
Timestamp: 1722198170

Remove Killers

The removal of killers on line 1774 resulted in a substantial decrease
in pre-LMR history average, so a negative history fill is applied to
counter it.

Passed Non-regression STC (vs #5513):
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 21984 W: 5886 L: 5645 D: 10453 Elo +3.81
Ptnml(0-2): 80, 2492, 5628, 2691, 101
https://tests.stockfishchess.org/tests/view/66a095894ff211be9d4ecb9d

Passed Non-regression LTC (vs #5513):
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 95430 W: 24141 L: 23995 D: 47294 Elo +0.53
Ptnml(0-2): 97, 10537, 26298, 10689, 94
https://tests.stockfishchess.org/tests/view/66a11c8d4ff211be9d4ecbf8

closes https://github.com/official-stockfish/Stockfish/pull/5517

Bench: 1660869
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Stéphane Nicolet
Date: Sun Jul 28 22:21:03 2024 +0200
Timestamp: 1722198063

Clean up comments for movepicker

Remove references to checks in MovePicker comments. Follow-up for
https://github.com/official-stockfish/Stockfish/pull/5498

closes https://github.com/official-stockfish/Stockfish/pull/5516

No functional change
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Michael Chaly
Date: Sun Jul 28 22:18:33 2024 +0200
Timestamp: 1722197913

Remove unneeded depth tracking in qsearch

Since simplification of quiet checks in qsearch this depth isn't used by
any function at all apart movepicker, which also doesn't use passed
qsearch depth in any way, so can be removed. No functional change.

closes https://github.com/official-stockfish/Stockfish/pull/5514

No functional change
see source
Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64
Author: Shawn Xu
Date: Sun Jul 28 22:13:47 2024 +0200
Timestamp: 1722197627

Simplify Away Killer Condition in Cutnode LMR

Passed Non-regression STC:
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 42944 W: 11240 L: 11024 D: 20680 Elo +1.75
Ptnml(0-2): 159, 5056, 10825, 5274, 158
https://tests.stockfishchess.org/tests/view/669c13384ff211be9d4ec69f

Passed Non-regression LTC:
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 163548 W: 41366 L: 41289 D: 80893 Elo +0.16
Ptnml(0-2): 109, 18246, 45007, 18283, 129
https://tests.stockfishchess.org/tests/view/669cb1254ff211be9d4ec73a

closes https://github.com/official-stockfish/Stockfish/pull/5513

Bench: 1178570
see source

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