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/mingw 7.3 on Ubuntu 18.04.
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!! latest version !!


Windows x64 for Haswell CPUs
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Linux x64
Author: Vizvezdenec
Date: Wed Aug 21 10:47:40 2019 +0200
Timestamp: 1566377260

Late move reduction, captures and CUT nodes

Expand of Stefan Geschwentner's original idea: we always do LMR for captures at cutnodes.

Passed STC
http://tests.stockfishchess.org/tests/view/5d5b2f8e0ebc5925cf1111b8
LLR: 2.96 (-2.94,2.94) [0.50,4.50]
Total: 36026 W: 8122 L: 7779 D: 20125 Elo +3.31

Passed LTC
http://tests.stockfishchess.org/tests/view/5d5b40c80ebc5925cf111353
LLR: 3.22 (-2.94,2.94) [0.00,3.50]
Total: 133502 W: 22508 L: 21943 D: 89051 Elo +1.47

Closes https://github.com/official-stockfish/Stockfish/pull/2273

Bench: 3494372
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Author: protonspring
Date: Wed Aug 21 09:34:46 2019 +0200
Timestamp: 1566372886

Tuned Futility Equation

@Vizvezdenec array suggested that alternate values may be better than current
master (see pull request #2270 ). I tuned some linear equations to more closely
represent his values and it passed. These futility values seem quite sensitive,
so perhaps additional Elo improvements can be found here.

STC
LLR: 2.95 (-2.94,2.94) [0.50,4.50]
Total: 12257 W: 2820 L: 2595 D: 6842 Elo +6.38
http://tests.stockfishchess.org/tests/view/5d5b2f360ebc5925cf1111ac

LTC
LLR: 2.96 (-2.94,2.94) [0.00,3.50]
Total: 20273 W: 3497 L: 3264 D: 13512 Elo +3.99
http://tests.stockfishchess.org/tests/view/5d5c0d250ebc5925cf111ac3

Closes https://github.com/official-stockfish/Stockfish/pull/2272

------------------------------------------
How to continue from there ?

a) we can try a simpler version for the futility margin, this would
be a simplification :
margin = 188 * (depth - improving)

b) on the other direction, we can try a complexification by trying
again to gain Elo with an complete array of futility values.

------------------------------------------

Bench: 4330402
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Linux x64
Author: Jean Gauthier
Date: Wed Aug 21 09:11:17 2019 +0200
Timestamp: 1566371477

Slight speep up fetching the endgame table

Replace calls to count(key) + operator[key] with a single call to find(key).
Replace the std::map with std::unordered_map which provide O(1) access,
although the map has a really small number of objects.

Test with [0..4] failed yellow:

TC 10+0.1
SPRT elo0: 0.00 alpha: 0.05 elo1: 4.00 beta: 0.05
LLR -2.96 [-2.94,2.94] (rejected)
Elo 1.01 [-0.87,3.08] (95%)
LOS 85.3%
Games 71860 [w:22.3%, l:22.2%, d:55.5%]
http://tests.stockfishchess.org/tests/view/5d5432210ebc5925cf109d61

Closes https://github.com/official-stockfish/Stockfish/pull/2269

No functional change
Windows x64 for Haswell CPUs
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Linux x64
Author: Alain SAVARD
Date: Wed Aug 14 22:15:48 2019 +0200
Timestamp: 1565813748

Assorted trivial cleanups (July 2019)

No functional change
Windows x64 for Haswell CPUs
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Linux x64
Author: Stefan Geschwentner
Date: Wed Aug 14 20:59:04 2019 +0200
Timestamp: 1565809144

Tweak unsafe checks

Remove mobility area for unsafe checks. Also separate the evaluation terms
for unsafe checks and blockers for king with adjusted weights.

STC:
LLR: 2.95 (-2.94,2.94) [0.50,4.50]
Total: 124526 W: 28292 L: 27504 D: 68730 Elo +2.20
http://tests.stockfishchess.org/tests/view/5d5138290ebc5925cf1070c3

LTC:
LLR: 2.96 (-2.94,2.94) [0.00,3.50]
Total: 84968 W: 14499 L: 14083 D: 56386 Elo +1.70
http://tests.stockfishchess.org/tests/view/5d527cfa0ebc5925cf107f93

Bench: 4139590
Windows x64 for Haswell CPUs
Windows x64 for modern computers
Windows x64
Windows 32
Linux x64 for Haswell CPUs
Linux x64 for modern computers
Linux x64
Author: joergoster
Date: Thu Aug 1 09:28:34 2019 +0200
Timestamp: 1564644514

Revert "Improve multiPV mode"

This reverts commit a8de07cc26999e2fef7298a63bfe349aaa4650fa.
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Author: xoto10
Date: Wed Jul 31 09:35:20 2019 +0200
Timestamp: 1564558520

Tune search constants

This is the result of a 200k tuning run at LTC:
http://tests.stockfishchess.org/tests/view/5d3576b70ebc5925cf0e9e1e

which passed quickly at LTC:
LLR: 2.95 (-2.94,2.94) [0.50,4.50]
Total: 12954 W: 2280 L: 2074 D: 8600 Elo +5.53
http://tests.stockfishchess.org/tests/view/5d3ff3f70ebc5925cf0f87a2

STC failed, but second LTC at [0,4] passed easily:
LLR: 2.96 (-2.94,2.94) [0.00,4.00]
Total: 8004 W: 1432 L: 1252 D: 5320 Elo +7.81
http://tests.stockfishchess.org/tests/view/5d407cff0ebc5925cf0f9119

Further work?
No doubt some of these changes produce most of the gain and some are neutral
or even bad, so further testing on individual/groups of parameters changed
here might show more gains. It does look like these tests might need to be
at LTC though, so maybe not too practical to do. See the thread in the pull
request for an interesting discussion:
https://github.com/official-stockfish/Stockfish/pull/2260

Bench: 4024328
Windows x64 for Haswell CPUs
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Author: protonspring
Date: Sun Jul 28 19:48:57 2019 +0200
Timestamp: 1564336137

Simplify weak lever

STC
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 14844 W: 3347 L: 3212 D: 8285 Elo +3.16
http://tests.stockfishchess.org/tests/view/5d3a2d7b0ebc5925cf0f1632

LTC
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 55261 W: 9374 L: 9309 D: 36578 Elo +0.41
http://tests.stockfishchess.org/tests/view/5d3a3d9e0ebc5925cf0f1786

Closes https://github.com/official-stockfish/Stockfish/pull/2257

bench: 3484124
Windows x64 for Haswell CPUs
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Author: mstembera
Date: Fri Jul 26 03:33:32 2019 +0200
Timestamp: 1564104812

Bug fix: always choose shortest mate in multithread mode

In current master, with the voting scheme the best thread selection may
pick a non mate or not the shortest mate thread. This patch fixes this bug.
Formatting suggestion by Jörg Oster.

Related past pull requests:
https://github.com/official-stockfish/Stockfish/pull/1074
https://github.com/official-stockfish/Stockfish/pull/1215

Passed a [-4..0] verification test with 3 threads:
LLR: 2.95 (-2.94,2.94) [-4.00,0.00]
Total: 57158 W: 11374 L: 11424 D: 34360 Elo -0.30
http://tests.stockfishchess.org/tests/view/5d22deb30ebc5925cf0caefd

Closes https://github.com/official-stockfish/Stockfish/pull/2226

No functional change (in single threaded mode)

----------------------------------------------------

Comment by Jörg Oster

Just one sample output to demonstrate the effect of this patch.
5 Threads, 1 GB Hash

+---+---+---+---+---+---+---+---+
| r | | b | | | r | k | |
+---+---+---+---+---+---+---+---+
| | | | n | | p | b | |
+---+---+---+---+---+---+---+---+
| | | p | | p | | p | |
+---+---+---+---+---+---+---+---+
| p | | | | | | P | |
+---+---+---+---+---+---+---+---+
| P | p | | | B | | N | Q |
+---+---+---+---+---+---+---+---+
| | q | | | | | P | |
+---+---+---+---+---+---+---+---+
| | | R | | | P | | |
+---+---+---+---+---+---+---+---+
| | | | R | | | K | |
+---+---+---+---+---+---+---+---+

Fen: r1b2rk1/3n1pb1/2p1p1p1/p5P1/Pp2B1NQ/1q4P1/2R2P2/3R2K1 w - - 8 34
Key: 38B4CA1067D4F477
Checkers:
ucinewgame
isready
readyok
go mate 17 searchmoves d1d7
info depth 65 seldepth 36 multipv 1 score mate 18 nodes 785875935 nps 8650448 hashfull 1000 tbhits 0 time 90848 pv d1d7 c8d7 g4f6 g7f6 g5f6 b3a3 g1g2 a3a1 h4g5 a1f6 g5f6 e6e5 c2c1 d7h3 g2h3 a8a6 h3g2 c6c5 f6a6 g8g7 c1c5 f7f6 a6e6 f8f7 c5c8 f6f5 e4d5 g7h6 e6f7 f5f4 f7e7 f4f3 d5f3 b4b3 c8h8
info depth 63 seldepth 36 multipv 1 score mate 17 nodes 785875935 nps 8650448 hashfull 1000 tbhits 0 time 90848 pv d1d7 c8d7 g4f6 g7f6 g5f6 b3a3 g1g2 a3a1 h4g5 a1f6 g5f6 e6e5 c2c1 d7h3 g2h3 a8a6 c1d1 b4b3 h3g2 c6c5 f6a6 g8g7 d1d7 g7g8 a6f6 b3b2 e4g6 b2b1q g6f7 f8f7 f6f7 g8h8 f7g7
bestmove d1d7 ponder c8d7
Windows x64 for Haswell CPUs
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Author: protonspring
Date: Fri Jul 26 02:12:23 2019 +0200
Timestamp: 1564099943

Remove operators for color

This is a non-functional and untested simplification. The increment operator
for color isn't really necessary and seems a bit unnatural to me.

Passed STC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 47027 W: 10589 L: 10518 D: 25920 Elo +0.52
http://tests.stockfishchess.org/tests/view/5d3472d10ebc5925cf0e8d3e

Closes https://github.com/official-stockfish/Stockfish/pull/2247

No functional change
Windows x64 for Haswell CPUs
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Linux x64 for modern computers
Linux x64
Author: Vizvezdenec
Date: Thu Jul 25 09:16:53 2019 +0200
Timestamp: 1564039013

Tweak of SEE pruning condition

passed STC
http://tests.stockfishchess.org/tests/view/5d386bda0ebc5925cf0ef49a
LLR: 2.95 (-2.94,2.94) [0.50,4.50]
Total: 56874 W: 12820 L: 12373 D: 31681 Elo +2.73

passed LTC
http://tests.stockfishchess.org/tests/view/5d38873a0ebc5925cf0ef86e
LLR: 2.95 (-2.94,2.94) [0.00,3.50]
Total: 43512 W: 7547 L: 7247 D: 28718 Elo +2.40

Additional thanks to @locutus2 , @miguel-l and @xoto10 for fruitful discussion.
There may be some more elo there since this tweak was the first one and numbers
are more or less arbitrary.

Closes https://github.com/official-stockfish/Stockfish/pull/2256

Bench 3935523
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Author: Alain SAVARD
Date: Thu Jul 25 09:05:08 2019 +0200
Timestamp: 1564038308

Pawn clean up

Non functional simplification when we find the passed pawns in pawn.cpp
and some code clean up. It also better follows the pattern "flag the pawn"
and "score the pawn".

-------------------------

The idea behind the third condition for candidate passed pawn is a little
bit difficult to visualize. Just for the record, the idea is the following:

Consider White e5 d4 against black e6. d4 can (in some endgames) push
to d5 and lever e6. Thanks to this sacrifice, or after d5xe6, we consider
e5 as "passed".

However:
- if White e5/d4 against black e6/c6: d4 cannot safely push to d5 since d5 is double attacked;
- if White e5/d4 against black e6/d5: d4 cannot safely push to d5 since it is occupied.

This is exactly what the following expression does:

```
&& (shift<Up>(support) & ~(theirPawns | dblAttackThem)))
```

--------------------------

http://tests.stockfishchess.org/tests/view/5d3325bb0ebc5925cf0e6e91
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 124666 W: 27586 L: 27669 D: 69411 Elo -0.23

Closes https://github.com/official-stockfish/Stockfish/pull/2255

No functional change
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Author: VoyagerOne
Date: Thu Jul 25 08:46:26 2019 +0200
Timestamp: 1564037186

LMR Tweak

Reset statScore to zero if negative and most stats shows >= 0

STC:
LLR: 2.95 (-2.94,2.94) [0.50,4.50]
Total: 23097 W: 5242 L: 4963 D: 12892 Elo +4.20
http://tests.stockfishchess.org/tests/view/5d31dd650ebc5925cf0e598f

LTC:
LLR: 2.95 (-2.94,2.94) [0.00,3.50]
Total: 227597 W: 39013 L: 38191 D: 150393 Elo +1.25
http://tests.stockfishchess.org/tests/view/5d31fcdf0ebc5925cf0e5c13

Closes https://github.com/official-stockfish/Stockfish/pull/2252

Bench: 3242229
Windows x64 for Haswell CPUs
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Linux x64 for modern computers
Linux x64
Author: Alain SAVARD
Date: Thu Jul 25 08:32:49 2019 +0200
Timestamp: 1564036369

Passed file cleanup

Protonspring had a successful functional simplification that removes the
PassedFile array using a simple linear equation.

Merge the additive term S(5, 10) of protonspring passed file simplification
(pull request https://github.com/official-stockfish/Stockfish/pull/2250)
into the PassedRank array. This harmless change has a different bench because
the candidate passer evaluation will always get less compared to #2250,
as we apply bonus = bonus /2.

Tested as a non-regression against #2250

Passed STC
http://tests.stockfishchess.org/tests/view/5d33427e0ebc5925cf0e6fa2
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 81459 W: 18174 L: 18171 D: 45114 Elo +0.01

Passed LTC
http://tests.stockfishchess.org/tests/view/5d335c8d0ebc5925cf0e731e
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 18525 W: 3176 L: 3052 D: 12297 Elo +2.33

Closes https://github.com/official-stockfish/Stockfish/pull/2250
Closes https://github.com/official-stockfish/Stockfish/pull/2251

Bench: 3859856
Windows x64 for Haswell CPUs
Windows x64 for modern computers
Windows x64
Windows 32
Linux x64 for Haswell CPUs
Linux x64 for modern computers
Linux x64
Author: Lolligerhans
Date: Thu Jul 25 08:23:43 2019 +0200
Timestamp: 1564035823

No influence on unsafeSquares of passers by pieces

Remove their pieces from influencing 'unsafeSquares' in passer
evaluation.

STC
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 36421 W: 8170 L: 8078 D: 20173 Elo +0.88
http://tests.stockfishchess.org/tests/view/5d22fc8e0ebc5925cf0cb26e

LTC
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 18927 W: 3253 L: 3129 D: 12545 Elo +2.28
http://tests.stockfishchess.org/tests/view/5d26e2b20ebc5925cf0d3218

Closes https://github.com/official-stockfish/Stockfish/pull/2248

Bench: 3285659
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Linux x64
Author: Vizvezdenec
Date: Thu Jul 25 08:17:11 2019 +0200
Timestamp: 1564035431

Tweak LMR and killers

Give extra stat bonus/malus in case of LMR for killers.

passed STC
http://tests.stockfishchess.org/tests/view/5d2c8e760ebc5925cf0dcf23
LLR: 2.95 (-2.94,2.94) [0.50,4.50]
Total: 67188 W: 15030 L: 14534 D: 37624 Elo +2.56

passed LTC
http://tests.stockfishchess.org/tests/view/5d2d0ce40ebc5925cf0de115
LLR: 2.96 (-2.94,2.94) [0.00,3.50]
Total: 144355 W: 24739 L: 24153 D: 95463 Elo +1.41

Closes https://github.com/official-stockfish/Stockfish/pull/2246

bench 3723147
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Windows 32
Linux x64 for Haswell CPUs
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Linux x64
Author: Alain SAVARD
Date: Thu Jul 25 08:07:55 2019 +0200
Timestamp: 1564034875

Space Invaders

Try a more ambitius simplification of the space bonus

STC http://tests.stockfishchess.org/tests/view/5d2b62c90ebc5925cf0da2a4
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 51299 W: 11320 L: 11257 D: 28722 Elo +0.43

LTC http://tests.stockfishchess.org/tests/view/5d2bac270ebc5925cf0db215
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 49761 W: 8409 L: 8335 D: 33017 Elo +0.52

Closes https://github.com/official-stockfish/Stockfish/pull/2243

bench: 3395999
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Linux x64
Author: Marco Costalba
Date: Sun Jul 14 15:21:08 2019 +0200
Timestamp: 1563110468

Fix bench

Bench: 3357457
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Author: Joost VandeVondele
Date: Sun Jul 14 14:47:50 2019 +0200
Timestamp: 1563108470

UCI_Elo implementation (#2225)

This exploits the recent fractional Skill Level, and is a result from some discussion in #2221 and the older #758.

Basically, if UCI_LimitStrength is set, it will internally convert UCI_Elo to a matching fractional Skill Level.
The Elo estimate is based on games at TC 60+0.6, Hash 64Mb, 8moves_v3.pgn, rated with Ordo, anchored to goldfish1.13 (CCRL 40/4 ~2000).
Note that this is mostly about internal consistency, the anchoring to CCRL is a bit weak, e.g. within this tournament,
goldfish and sungorus only have a 200Elo difference, their rating difference on CCRL is 300Elo.

I propose that we continue to expose 'Skill Level' as an UCI option, for backwards compatibility.

The result of a tournament under those conditions are given by the following table, where the player name reflects the UCI_Elo.

# PLAYER : RATING ERROR POINTS PLAYED (%) CFS(%)
1 Elo2837 : 2792.2 50.8 536.5 711 75 100
2 Elo2745 : 2739.0 49.0 487.5 711 69 100
3 Elo2654 : 2666.4 49.2 418.0 711 59 100
4 Elo2562 : 2604.5 38.5 894.5 1383 65 100
5 Elo2471 : 2515.2 38.1 651.5 924 71 100
6 Elo2380 : 2365.9 35.4 478.5 924 52 100
7 Elo2289 : 2290.0 28.0 864.0 1596 54 100
8 sungorus1.4 : 2204.9 27.8 680.5 1596 43 60
9 Elo2197 : 2201.1 30.1 523.5 924 57 100
10 Elo2106 : 2103.8 24.5 730.5 1428 51 100
11 Elo2014 : 2030.5 30.3 377.5 756 50 98
12 goldfish1.13 : 2000.0 ---- 511.0 1428 36 100
13 Elo1923 : 1928.5 30.9 641.5 1260 51 100
14 Elo1831 : 1829.0 42.1 370.5 756 49 100
15 Elo1740 : 1738.3 42.9 277.5 756 37 100
16 Elo1649 : 1625.0 42.1 525.5 1260 42 100
17 Elo1558 : 1521.5 49.9 298.0 756 39 100
18 Elo1467 : 1471.3 51.3 246.5 756 33 100
19 Elo1375 : 1407.1 51.9 183.0 756 24 ---

It can be observed that all set Elos correspond within the error bars with the observed Ordo rating.

No functional change
Windows x64 for Haswell CPUs
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Linux x64
Author: protonspring
Date: Sun Jul 14 14:46:10 2019 +0200
Timestamp: 1563108370

Remove std::pow from reduction. (#2234)

This is a functional simplification that removes the std::pow from reduction. The resulting reduction values are within 1% of master.

This is a simplification because i believe an fp addition and multiplication is much faster than a call to std::pow() which is historically slow and performance varies widely on different architectures.

STC
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 23471 W: 5245 L: 5127 D: 13099 Elo +1.75
http://tests.stockfishchess.org/tests/view/5d27ac1b0ebc5925cf0d476b

LTC
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 51533 W: 8736 L: 8665 D: 34132 Elo +0.48
http://tests.stockfishchess.org/tests/view/5d27b74e0ebc5925cf0d493c

Bench 3765158
Windows x64 for Haswell CPUs
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Windows x64
Windows 32
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Linux x64
Author: 31m059
Date: Sun Jul 14 14:42:30 2019 +0200
Timestamp: 1563108150

Just blockSq, not forward file. Bench: 3377831 (#2240)

This is another functional simplification to Stockfish passed pawn evaluation.

Stockfish evaluates some pawns which are not yet passed as "candidate" passed pawns, which are given half the bonus of fully passed ones. Prior to this commit, Stockfish considered a passed pawn to be a "candidate" if (a) it would not be a passed pawn if moved one square forward (the blocking square), or (b) there were other pawns (of either color) in front of it on the file. This latter condition used a fairly complicated method, forward_file_bb; here, rather than inspect the entire forward file, we simply re-use the blocking square. As a result, some pawns previously considered "candidates", but which are able to push forward, no longer have their bonus halved.

Simplification tests passed quickly at both STC and LTC. The results from both tests imply that this simplification is, most likely, additionally a small Elo gain, with a LTC likelihood of superiority of 87 percent.

STC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 12908 W: 2909 L: 2770 D: 7229 Elo +3.74
http://tests.stockfishchess.org/tests/view/5d2a1c880ebc5925cf0d9006

LTC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 20723 W: 3591 L: 3470 D: 13662 Elo +2.03
http://tests.stockfishchess.org/tests/view/5d2a21fd0ebc5925cf0d9118

Bench: 3377831
Windows x64 for Haswell CPUs
Windows x64 for modern computers
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Linux x64
Author: Michael Chaly
Date: Sun Jul 14 14:41:28 2019 +0200
Timestamp: 1563108088

tviigg. (#2238)

Current master code made sence when we had 2 types of bonuses for protected path to queen. But it was simplified so we have only one bonus now and code was never cleaned.
This non-functional simplification removes useless defendedsquares bitboard and removes one bitboard assignment (defendedSquares &= attackedBy[Us][ALL_PIECES] + defendedSquares & blockSq becomes just attackedBy[Us][ALL_PIECES] & blockSq also we never assign defendedSquares = squaresToQueen because we don't need it).
So should be small non-functional speedup.
Passed simplification SPRT.
http://tests.stockfishchess.org/tests/view/5d2966ef0ebc5925cf0d7659
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 23319 W: 5152 L: 5034 D: 13133 Elo +1.76

bench 3361902
Windows x64 for Haswell CPUs
Windows x64 for modern computers
Windows x64
Windows 32
Linux x64 for Haswell CPUs
Linux x64 for modern computers
Linux x64
Author: 31m059
Date: Sun Jul 14 14:40:45 2019 +0200
Timestamp: 1563108045

Linear formula for w. Bench: 3328507 (#2239)

In Stockfish, both the middlegame and endgame bonus for a passed pawn are calculated as a product of two factors. The first is k, chosen based on the presence of defended and unsafe squares. The second is w, a quadratic function of the pawn's rank. Both are only applied if the pawn's relative rank is at least RANK_4.

It does not appear that the complexity of a quadratic function is necessary for w. Here, we replace it with a simpler linear one, which performs equally at both STC and LTC.

STC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 46814 W: 10386 L: 10314 D: 26114 Elo +0.53
http://tests.stockfishchess.org/tests/view/5d29686e0ebc5925cf0d76a1

LTC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 82372 W: 13845 L: 13823 D: 54704 Elo +0.09
http://tests.stockfishchess.org/tests/view/5d2980650ebc5925cf0d7bfd

Bench: 3328507
Windows x64 for Haswell CPUs
Windows x64 for modern computers
Windows x64
Windows 32
Linux x64 for Haswell CPUs
Linux x64 for modern computers
Linux x64
Author: Stefan Geschwentner
Date: Sat Jul 13 05:49:14 2019 +0200
Timestamp: 1562989754

Full bonus for LMR stats update

Simplify previous commit by using the full bonus for LMR-triggered stats update.

STC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 23684 W: 5255 L: 5137 D: 13292 Elo +1.73
http://tests.stockfishchess.org/tests/view/5d2826660ebc5925cf0d5180

LTC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 16245 W: 2832 L: 2704 D: 10709 Elo +2.74
http://tests.stockfishchess.org/tests/view/5d282e9c0ebc5925cf0d529b

Closes https://github.com/official-stockfish/Stockfish/pull/2236

Bench: 3361902
Windows x64 for Haswell CPUs
Windows x64 for modern computers
Windows x64
Windows 32
Linux x64 for Haswell CPUs
Linux x64 for modern computers
Linux x64
Author: Stefan Geschwentner
Date: Fri Jul 12 09:26:45 2019 +0200
Timestamp: 1562916405

Late Move reduction and continuation history

Update continuation history after LMR-triggered full depth research.
Directly after a LMR-triggered full depth research, we update the
continuation history for quiet moves (but with only half stat bonus).

STC:
LLR: 2.96 (-2.94,2.94) [0.50,4.50]
Total: 39657 W: 8966 L: 8604 D: 22087 Elo +3.17
http://tests.stockfishchess.org/tests/view/5d279fa40ebc5925cf0d4566

LTC:
LLR: 2.96 (-2.94,2.94) [0.50,3.50]
Total: 32582 W: 5740 L: 5427 D: 21415 Elo +3.34
http://tests.stockfishchess.org/tests/view/5d27dbf90ebc5925cf0d4b7e

Bench: 3239357

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