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.
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!! latest version !!


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: Sun Dec 4 14:17:15 2022 +0100
Timestamp: 1670159835

Stockfish 15.1

Official release version of Stockfish 15.1

Bench: 3467381

---

Today, we have the pleasure to announce Stockfish 15.1.

As usual, downloads will be freely available at stockfishchess.org/download

*Elo gain and competition results*

With this release, version 5 of the NNUE neural net architecture has
been introduced, and the training data has been extended to include
Fischer random chess (FRC) positions. As a result, Elo gains are largest
for FRC, reaching up to 50 Elo for doubly randomized FRC[1] (DFRC).
More importantly, also for standard chess this release progressed and
will win two times more game pairs than it loses[2] against
Stockfish 15. Stockfish continues to win in a dominating way[3] all
chess engine tournaments, including the TCEC Superfinal, Cup, FRC, DFRC,
and Swiss as well as the CCC Bullet, Blitz, and Rapid events.

*New evaluation*

This release also introduces a new convention for the evaluation that
is reported by search. An evaluation of +1 is now no longer tied to the
value of one pawn, but to the likelihood of winning the game. With
a +1 evaluation, Stockfish has now a 50% chance of winning the game
against an equally strong opponent. This convention scales down
evaluations a bit compared to Stockfish 15 and allows for consistent
evaluations in the future.

*ChessBase settlement*

In this release period, the Stockfish team has successfully enforced
its GPL license against ChessBase. This has been an intense process that
included filing a lawsuit[4], a court hearing[5], and finally
negotiating a settlement[6] that established that ChessBase infringed on
the license by not distributing the Stockfish derivatives Fat Fritz 2
and Houdini 6 as free software, and that ensures ChessBase will respect
the Free Software principles in the future. This settlement has been
covered by major chess sites (see e.g. lichess.org[7] and chess.com[8]),
and we are proud that it has been hailed as a ‘historic violation
settlement[9]’ by the Software Freedom Conservancy.

*Thank you*

The Stockfish project builds on a thriving community of enthusiasts
(thanks everybody!) that contribute their expertise, time, and resources
to build a free and open-source chess engine that is robust, widely
available, and very strong. We invite our chess fans to join the
fishtest testing framework and programmers to contribute to the
project[10].

The Stockfish team

[1] https://tests.stockfishchess.org/tests/view/638a6170d2b9c924c4c62cb4
[2] https://tests.stockfishchess.org/tests/view/638a4dd7d2b9c924c4c6297b
[3] https://en.wikipedia.org/wiki/Stockfish_(chess)#Competition_results
[4] https://stockfishchess.org/blog/2021/our-lawsuit-against-chessbase/
[5] https://stockfishchess.org/blog/2022/public-court-hearing-soon/
[6] https://stockfishchess.org/blog/2022/chessbase-stockfish-agreement/
[7] https://lichess.org/blog/Y3u1mRAAACIApBVn/settlement-reached-in-stockfish-v-chessbase
[8] https://www.chess.com/news/view/chessbase-stockfish-reach-settlement
[9] https://sfconservancy.org/news/2022/nov/28/sfc-named-trusted-party-in-gpl-case/
[10] https://stockfishchess.org/get-involved/
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: Fri Dec 2 20:06:59 2022 +0100
Timestamp: 1670008019

Fix bestThread selection

If multiple threads have the same best move,
pick the thread with the largest contribution to the confidence vote.
This thread will later be used to display PV, so this patch is
about user-friendliness and/or least surprises, it non-functional for playing strenght.

closes https://github.com/official-stockfish/Stockfish/pull/4246

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: VoyagerOne
Date: Fri Dec 2 20:05:50 2022 +0100
Timestamp: 1670007950

Simply do full sort on captures.

STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 42712 W: 11413 L: 11203 D: 20096 Elo +1.71
Ptnml(0-2): 145, 4661, 11544, 4851, 155
https://tests.stockfishchess.org/tests/view/6384df57d2b9c924c4c53900

LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 239072 W: 64065 L: 64067 D: 110940 Elo -0.00
Ptnml(0-2): 106, 23735, 71859, 23727, 109
https://tests.stockfishchess.org/tests/view/63851120d2b9c924c4c541ee

closes https://github.com/official-stockfish/Stockfish/pull/4249

Bench: 3467381
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: VoyagerOne
Date: Fri Dec 2 20:03:49 2022 +0100
Timestamp: 1670007829

Remove PvNode Parameter for cutoff LMR

STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 198520 W: 52673 L: 52632 D: 93215 Elo +0.07
Ptnml(0-2): 645, 22241, 53499, 22178, 697
https://tests.stockfishchess.org/tests/view/63746e8f9849fa7a36a6698f

LTC:
LLR: 2.97 (-2.94,2.94) <-1.75,0.25>
Total: 253568 W: 67487 L: 67501 D: 118580 Elo -0.02
Ptnml(0-2): 109, 25222, 76141, 25198, 114
https://tests.stockfishchess.org/tests/view/63839859d2b9c924c4c4feb7

closes https://github.com/official-stockfish/Stockfish/pull/4248

Bench: 3733322
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: Guenther Demetz
Date: Wed Nov 23 21:45:06 2022 +0100
Timestamp: 1669236306

Correctly output lowerbound/upperbound in threaded searches

fixes the lowerbound/upperbound output by taking the alpha,beta bracket
into account also if a bestThread is selected that is different from the master thread.

Instead of keeping track which bounds where used in the specific search,
in this version we simply store the quality (exact, upperbound,
lowerbound) of the score along with the actual score as information on
rootMove.

closes https://github.com/official-stockfish/Stockfish/pull/4239

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: peregrineshahin
Date: Wed Nov 23 21:36:22 2022 +0100
Timestamp: 1669235782

Simplify both quiet check evasions' conditions

passed Non-regression STC:
https://tests.stockfishchess.org/tests/view/6370b647f1b748d4819e0b64
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 162904 W: 43249 L: 43171 D: 76484 Elo +0.17
Ptnml(0-2): 491, 17089, 46220, 17155, 497

closes https://github.com/official-stockfish/Stockfish/pull/4228

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: VoyagerOne
Date: Wed Nov 23 21:25:14 2022 +0100
Timestamp: 1669235114

Skip full depth search in LMR depending on depth

dynamically adjust newDepth, and skip full depth search if newDepth doesn't exceed the previous search depth.
This affects the used newDepth for future searches, and influences the stat bonus for the move.

Passed STC:
https://tests.stockfishchess.org/tests/view/63795500aa34433735bc1cfe
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 112776 W: 30082 L: 29663 D: 53031 Elo +1.29
Ptnml(0-2): 352, 12453, 30423, 12744, 416

Passed LTC:
https://tests.stockfishchess.org/tests/view/6379ea39aa34433735bc2f9b
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 83576 W: 22559 L: 22169 D: 38848 Elo +1.62
Ptnml(0-2): 38, 8011, 25303, 8395, 41

closes https://github.com/official-stockfish/Stockfish/pull/4240

Bench: 4390318
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: Sun Nov 20 10:00:42 2022 +0100
Timestamp: 1668934842

Update Top CPU Contributors

list as of 2022-11-19. Thanks!

closes https://github.com/official-stockfish/Stockfish/pull/4234

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: Sun Nov 20 09:59:35 2022 +0100
Timestamp: 1668934775

Update WDL model for current SF

This updates the WDL model based on the LTC statistics (2M games).

Relatively small change, note that this also adjusts the NormalizeToPawnValue (now 361),
to keep win prob at 50% for 100cp.

closes https://github.com/official-stockfish/Stockfish/pull/4236

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: Sun Nov 20 09:58:07 2022 +0100
Timestamp: 1668934687

Fix a missing conversion

This conversion to cp was overlooked.

closes https://github.com/official-stockfish/Stockfish/pull/4235

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: VoyagerOne
Date: Sat Nov 19 09:29:04 2022 +0100
Timestamp: 1668846544

Simplification away Cutoff Reset

STC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 150184 W: 39913 L: 39819 D: 70452 Elo +0.22
Ptnml(0-2): 493, 16796, 40474, 16782, 547
https://tests.stockfishchess.org/tests/view/63723e9e54d69a2f33911d3c

LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 58880 W: 15890 L: 15717 D: 27273 Elo +1.02
Ptnml(0-2): 35, 5765, 17659, 5954, 27
https://tests.stockfishchess.org/tests/view/6373baf49849fa7a36a65427

closes https://github.com/official-stockfish/Stockfish/pull/4231

Bench: 4035152
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: Sat Nov 19 09:23:26 2022 +0100
Timestamp: 1668846206

Do shallower search in case of lmr being not successful enough

In case of a move passing LMR but it results being not too far from
the current best search result produce a full depth search with reduced depth.

Original idea by lonfom169 .

Passed STC:
https://tests.stockfishchess.org/tests/view/6373409b54d69a2f33913fbd
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 169504 W: 45351 L: 44848 D: 79305 Elo +1.03
Ptnml(0-2): 598, 18853, 45353, 19344, 604

Passed LTC:
https://tests.stockfishchess.org/tests/view/6374c58528e3405283eb8d2d
LLR: 2.96 (-2.94,2.94) <0.50,2.50>
Total: 51144 W: 13802 L: 13471 D: 23871 Elo +2.25
Ptnml(0-2): 19, 4928, 15362, 5229, 34

closes https://github.com/official-stockfish/Stockfish/pull/4230

bench 4277005
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: Mon Nov 7 21:42:04 2022 +0100
Timestamp: 1667853724

speedup CI

Github Actions allows us to use up to 20 workers.
This way we can launch multiple different checks
at the same time and optimize the overall time
the CI takes a bit.

closes https://github.com/official-stockfish/Stockfish/pull/4223

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: Mon Nov 7 08:00:05 2022 +0100
Timestamp: 1667804405

Remove trend

Simplify trend away.

passed Non-regression STC:
https://tests.stockfishchess.org/tests/view/63642a63a90afcecbd1cb887
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 130000 W: 34683 L: 34567 D: 60750 Elo +0.31
Ptnml(0-2): 455, 14424, 35135, 14522, 464

passed Non-regression LTC:
https://tests.stockfishchess.org/tests/view/636566fda90afcecbd1cded9
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 81592 W: 21938 L: 21787 D: 37867 Elo +0.64
Ptnml(0-2): 42, 8035, 24490, 8188, 41

closes https://github.com/official-stockfish/Stockfish/pull/4222

Bench: 4239512
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: Mon Nov 7 07:56:58 2022 +0100
Timestamp: 1667804218

Change versioning and save binaries as CI artifacts

For development versions of Stockfish, the version will now look like
dev-20221107-dca9a0533
indicating a development version, the date of the last commit,
and the git SHA of that commit. If git is not available,
the fallback is the date of compilation. Releases will continue to be
versioned as before.

Additionally, this PR extends the CI to create binary artifacts,
i.e. pushes to master will automatically build Stockfish and upload
the binaries to github.

closes https://github.com/official-stockfish/Stockfish/pull/4220

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: Sat Nov 5 09:15:53 2022 +0100
Timestamp: 1667636153

Normalize evaluation

Normalizes the internal value as reported by evaluate or search
to the UCI centipawn result used in output. This value is derived from
the win_rate_model() such that Stockfish outputs an advantage of
"100 centipawns" for a position if the engine has a 50% probability to win
from this position in selfplay at fishtest LTC time control.

The reason to introduce this normalization is that our evaluation is, since NNUE,
no longer related to the classical parameter PawnValueEg (=208). This leads to
the current evaluation changing quite a bit from release to release, for example,
the eval needed to have 50% win probability at fishtest LTC (in cp and internal Value):

June 2020 : 113cp (237)
June 2021 : 115cp (240)
April 2022 : 134cp (279)
July 2022 : 167cp (348)

With this patch, a 100cp advantage will have a fixed interpretation,
i.e. a 50% win chance. To keep this value steady, it will be needed to update the win_rate_model()
from time to time, based on fishtest data. This analysis can be performed with
a set of scripts currently available at https://github.com/vondele/WLD_model

fixes https://github.com/official-stockfish/Stockfish/issues/4155
closes https://github.com/official-stockfish/Stockfish/pull/4216

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: Sat Nov 5 09:15:14 2022 +0100
Timestamp: 1667636114

Mark variable as potentially unused

fixes CI when compiled with -Werror

closes https://github.com/official-stockfish/Stockfish/pull/4221

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: kurt22i
Date: Sun Oct 30 16:19:09 2022 +0100
Timestamp: 1667143149

Adjust reduction less at medium depths

This patch dampens the reduction increase/decrease from statScore at mid-range depths.
Inspired by patterns noticed in this tune: https://tests.stockfishchess.org/tests/view/635188930e5f47a8d0ffe8f5

Passed STC:
https://tests.stockfishchess.org/tests/view/63599dfd6b27ef94d9ec04af
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 87464 W: 23519 L: 23134 D: 40811 Elo +1.53
Ptnml(0-2): 319, 9599, 23524, 9958, 332

Passed LTC:
https://tests.stockfishchess.org/tests/view/635a73046b27ef94d9ec2313
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 154792 W: 41746 L: 41214 D: 71832 Elo +1.19
Ptnml(0-2): 79, 15181, 46349, 15703, 84

closes https://github.com/official-stockfish/Stockfish/pull/4213

Bench 4271738
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: Sun Oct 30 16:17:49 2022 +0100
Timestamp: 1667143069

Update MacOS CI

move to 12 following actions runner update deprecation
(see https://github.com/actions/runner-images/issues/5583)

closes https://github.com/official-stockfish/Stockfish/pull/4212

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: Clausable
Date: Thu Oct 27 08:15:46 2022 +0200
Timestamp: 1666851346

Fix README typos, update AUTHORS

closes https://github.com/official-stockfish/Stockfish/pull/4208

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: dav1312
Date: Wed Oct 26 20:28:12 2022 +0200
Timestamp: 1666808892

Add issue template

Add an issue template using GitHub's form schema
https://docs.github.com/en/communities/using-templates-to-encourage-useful-issues-and-pull-requests/syntax-for-githubs-form-schema

closes https://github.com/official-stockfish/Stockfish/pull/4210

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 Oct 23 20:22:04 2022 +0200
Timestamp: 1666549324

Use TT moves more often in qsearch

During the recapture phase of quiescence search (where we limit the generated moves to recaptures on the last seen capture square),
the move picker will now emit the tt move, even if the tt move is not a recapture.

Passed STC :
https://tests.stockfishchess.org/tests/view/6350df2928d3a71cb1eef838
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 90280 W: 24001 L: 23845 D: 42434 Elo +0.60
Ptnml(0-2): 273, 9779, 24941, 9813, 334

Passed LTC :
https://tests.stockfishchess.org/tests/view/6351308b28d3a71cb1ef06ce
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 104504 W: 27937 L: 27807 D: 48760 Elo +0.43
Ptnml(0-2): 54, 10378, 31260, 10504, 56

closes https://github.com/official-stockfish/Stockfish/pull/4206

Bench: 4540268
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: Clement
Date: Sun Oct 23 20:18:08 2022 +0200
Timestamp: 1666549088

Add RISC-V 64-bit support

adds a riscv64 target architecture to the Makefile to support RISC-V 64-bit.
Compiled and tested on VisionFive 2 board.

closes https://github.com/official-stockfish/Stockfish/pull/4205

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: Sun Oct 23 20:08:18 2022 +0200
Timestamp: 1666548498

enable bit manipulation instruction set 1

bmi1 enables the use of _blsr_u64 for pop_lsb, and is availabe when avx2 is.

verified a small speedup (0.2 - 0.6%)

closes https://github.com/official-stockfish/Stockfish/pull/4202

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: MinetaS
Date: Sun Oct 23 19:58:47 2022 +0200
Timestamp: 1666547927

Apply -flto-partition=one / -flto=full

This patch fixes a potential bug derived from an incompatibility between LTO and top-level assembly code (INCBIN).

Passed non-regression STC (master e90341f):
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 119352 W: 31986 L: 31862 D: 55504 Elo +0.36
Ptnml(0-2): 439, 12624, 33400, 12800, 413
https://tests.stockfishchess.org/tests/view/634aacf84bc7650f0755188b

closes https://github.com/official-stockfish/Stockfish/pull/4201

No functional change
see source

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