Stockfish

[Homayoun]

Author: Shahin M. Shahin
Date: Sat Dec 30 12:19:48 2023 +0100
Timestamp: 1703935188

Fix scores from reverse futility pruning

This fixes futility pruning return values after recent tweaks, `eval` is
guaranteed to be less than the mate-in range but it can be as low value such
that the average between eval and beta can still fall in the mated-in range when
beta is as low in mated range. i.e. (eval + beta) / 2 being at mated-range which
can break mates.

Passed non-regression STC:
https://tests.stockfishchess.org/tests/ ... f82b955139
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 117408 W: 29891 L: 29761 D: 57756 Elo +0.38
Ptnml(0-2): 386, 13355, 31120, 13429, 414

Passed non-regression LTC:
https://tests.stockfishchess.org/tests/ ... f82b9557bd
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 60240 W: 14962 L: 14786 D: 30492 Elo +1.02
Ptnml(0-2): 22, 6257, 17390, 6425, 26

changes signature at higher depth e.g. `128 1 15`

closes https://github.com/official-stockfish/S ... /pull/4944

Bench: 1304666
https://abrok.eu/stockfish/

[Homayoun]

Author: Stefan Geschwentner
Date: Sun Dec 31 20:09:09 2023 +0100
Timestamp: 1704049749

Tweak static eval history update

Modify the applied static eval bonus for main and pawn history with different
factors for positive and negative values.

Passed STC:
https://tests.stockfishchess.org/tests/ ... f82b957bb0
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 12512 W: 3308 L: 3027 D: 6177 Elo +7.80
Ptnml(0-2): 32, 1372, 3189, 1609, 54

Passed LTC:
https://tests.stockfishchess.org/tests/ ... f82b957cd2
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 35946 W: 9128 L: 8809 D: 18009 Elo +3.08
Ptnml(0-2): 19, 3879, 9862, 4190, 23

closes https://github.com/official-stockfish/S ... /pull/4952

Bench: 1392883

https://abrok.eu/stockfish/

[Homayoun]

Author: Disservin
Date: Mon Jan 1 02:31:25 2024 +0100
Timestamp: 1704072685

Fix formatting in search.cpp

fixes the formatting for 1fe562fdf32c153f82929660197f8b97469f76b4
https://abrok.eu/stockfish/

[Homayoun]

Author: FauziAkram
Date: Thu Jan 4 15:56:53 2024 +0100
Timestamp: 1704380213

Remove redundant int cast

Remove a redundant int cast in the calculation of fwdOut. The variable
OutputType is already defined as std::int32_t, which is an integer type, making
the cast unnecessary.

closes https://github.com/official-stockfish/S ... /pull/4961

No functional change
https://abrok.eu/stockfish/

note: On Thursday January 4th we had 9 releases , some of them showed progress in ELO , above is the last one of those releases.

[Homayoun]

Author: mstembera
Date: Sun Jan 7 13:41:50 2024 +0100
Timestamp: 1704631310

Introduce BAD_QUIET movepicker stage

Split quiets into good and bad as we do with captures. When we find
the first quiet move below a certain threshold that has been sorted we
consider all subsequent quiets bad. Inspired by @locutus2 idea to skip
bad captures.

Passed STC:
https://tests.stockfishchess.org/tests/ ... f82b95fa17
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 138688 W: 35566 L: 35096 D: 68026 Elo +1.18
Ptnml(0-2): 476, 16367, 35183, 16847, 471

Passed LTC:
https://tests.stockfishchess.org/tests/ ... f82b960ad0
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 84108 W: 21468 L: 21048 D: 41592 Elo +1.73
Ptnml(0-2): 38, 9355, 22858, 9755, 48

closes https://github.com/official-stockfish/S ... /pull/4970

Bench: 1336907

https://abrok.eu/stockfish/

[Homayoun]

Author: mstembera
Date: Sun Jan 7 13:41:50 2024 +0100
Timestamp: 1704631310

Introduce BAD_QUIET movepicker stage

Split quiets into good and bad as we do with captures. When we find
the first quiet move below a certain threshold that has been sorted we
consider all subsequent quiets bad. Inspired by @locutus2 idea to skip
bad captures.

Passed STC:
https://tests.stockfishchess.org/tests/ ... f82b95fa17
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 138688 W: 35566 L: 35096 D: 68026 Elo +1.18
Ptnml(0-2): 476, 16367, 35183, 16847, 471

Passed LTC:
https://tests.stockfishchess.org/tests/ ... f82b960ad0
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 84108 W: 21468 L: 21048 D: 41592 Elo +1.73
Ptnml(0-2): 38, 9355, 22858, 9755, 48

closes https://github.com/official-stockfish/S ... /pull/4970

Bench: 1336907
https://abrok.eu/stockfish/

[Homayoun]

Author: mstembera
Date: Sun Jan 7 13:41:50 2024 +0100
Timestamp: 1704631310

Introduce BAD_QUIET movepicker stage

Split quiets into good and bad as we do with captures. When we find
the first quiet move below a certain threshold that has been sorted we
consider all subsequent quiets bad. Inspired by @locutus2 idea to skip
bad captures.

Passed STC:
https://tests.stockfishchess.org/tests/ ... f82b95fa17
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 138688 W: 35566 L: 35096 D: 68026 Elo +1.18
Ptnml(0-2): 476, 16367, 35183, 16847, 471

Passed LTC:
https://tests.stockfishchess.org/tests/ ... f82b960ad0
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 84108 W: 21468 L: 21048 D: 41592 Elo +1.73
Ptnml(0-2): 38, 9355, 22858, 9755, 48

closes https://github.com/official-stockfish/S ... /pull/4970

Bench: 1336907
https://abrok.eu/stockfish/

[Homayoun]

Author: mstembera
Date: Sun Jan 7 13:41:50 2024 +0100
Timestamp: 1704631310

Introduce BAD_QUIET movepicker stage

Split quiets into good and bad as we do with captures. When we find
the first quiet move below a certain threshold that has been sorted we
consider all subsequent quiets bad. Inspired by @locutus2 idea to skip
bad captures.

Passed STC:
https://tests.stockfishchess.org/tests/ ... f82b95fa17
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 138688 W: 35566 L: 35096 D: 68026 Elo +1.18
Ptnml(0-2): 476, 16367, 35183, 16847, 471

Passed LTC:
https://tests.stockfishchess.org/tests/ ... f82b960ad0
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 84108 W: 21468 L: 21048 D: 41592 Elo +1.73
Ptnml(0-2): 38, 9355, 22858, 9755, 48

closes https://github.com/official-stockfish/S ... /pull/4970

Bench: 1336907
https://abrok.eu/stockfish/

[Homayoun]

Author: Muzhen Gaming
Date: Sat Dec 2 11:30:47 2023 +0100
Timestamp: 1701513047

Simplify move history reduction

Recent VLTC search tuning has suggested that the depth limit can be increased
by a lot. This patch simplifies away the depth-based bonus from statScore
reduction, making the divisor a constant.

Passed STC:
https://tests.stockfishchess.org/tests/ ... c573549791
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 91520 W: 23130 L: 22967 D: 45423 Elo +0.62
Ptnml(0-2): 282, 10947, 23141, 11106, 284

Passed LTC:
https://tests.stockfishchess.org/tests/ ... c57354a581
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 352902 W: 86796 L: 86917 D: 179189 Elo -0.12
Ptnml(0-2): 190, 40227, 95741, 40100, 193

closes https://github.com/official-stockfish/S ... /pull/4886

Bench: 1297179

[Sedat Canbaz]

As usual,
Many thanks Mr. Homayoun, for all the news...
And BIG thanks to all Stockfish developers...

Greetings )