1
0
Fork 0
mirror of https://github.com/sockspls/badfish synced 2025-04-30 00:33:09 +00:00
Commit graph

2775 commits

Author SHA1 Message Date
Dubslow
27042fe949 Linearize corrHist
Passed STC: https://tests.stockfishchess.org/tests/view/66919cdec6827afcdcee146f
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 130656 W: 33579 L: 33461 D: 63616
Ptnml(0-2): 394, 15548, 33318, 15682, 386

Passed VVLTC: https://tests.stockfishchess.org/tests/view/6691acb2c6827afcdcee1645
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 160314 W: 40925 L: 40854 D: 78535
Ptnml(0-2): 12, 14754, 50551, 14831, 9

closes https://github.com/official-stockfish/Stockfish/pull/5489

bench 1380295
2024-07-19 08:36:25 +02:00
yl25946
7bb45d05fa Replace ternary with std::min
equivalent and more readable.

closes https://github.com/official-stockfish/Stockfish/pull/5488

No functional change
2024-07-19 08:34:02 +02:00
Guenther Demetz
c755bc1a73 Simplify improving condition
if we were in check at our previous move we look back until we weren't
in check and take the staticEval of that position as reference.

Passed STC:
https://tests.stockfishchess.org/tests/view/668ba7b65034141ae5996665
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 74784 W: 19454 L: 19274 D: 36056
Ptnml(0-2): 260, 8874, 18952, 9038, 268

Passted LTC:
https://tests.stockfishchess.org/tests/view/668cb2db5034141ae599678b
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 241488 W: 61166 L: 61171 D: 119151
Ptnml(0-2): 190, 27154, 66062, 27147, 191

closes https://github.com/official-stockfish/Stockfish/pull/5492

bench: 1368313
2024-07-19 08:32:16 +02:00
Michael Chaly
de2bf1a186 Remove quiet history pruning depth limit
This patch removes lmrDepth limit for quiet moves history based pruning.

Previously removal of this type of depth limits was considered bad because it
was performing bad for matetrack - but with this pruning heuristic this
shouldn't be that bad because it's "naturally" depth limited by history
threshold and should be completely disabled at depth >= 15 or so.  Also this
heuristic in previous years was known to scale non-linearly - bigger lmrDepth
thresholds were better at longer time controls and removing it completely
probably should scale pretty well.

Passed STC:
https://tests.stockfishchess.org/tests/view/6692b89b4ff211be9d4eab21
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 114464 W: 29675 L: 29545 D: 55244
Ptnml(0-2): 372, 12516, 31329, 12640, 375

Passed LTC:
https://tests.stockfishchess.org/tests/view/6692c4554ff211be9d4eab3d
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 67746 W: 17182 L: 17014 D: 33550
Ptnml(0-2): 28, 6993, 19652, 7183, 17

closes https://github.com/official-stockfish/Stockfish/pull/5485

Bench: 1250388
2024-07-15 13:35:06 +02:00
MinetaS
2b37b151dd Use ValueList to represent searched moves array
This PR replaces a pair of array and size with existing ValueList class.
Removes two local variables in search and two parameters of
update_all_stats.

Passed non-regression STC:
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 227040 W: 58472 L: 58463 D: 110105
Ptnml(0-2): 495, 23572, 65427, 23481, 545
https://tests.stockfishchess.org/tests/view/669299204ff211be9d4e98dc

closes https://github.com/official-stockfish/Stockfish/pull/5484

No functional change
2024-07-15 13:30:47 +02:00
FauziAkram
7395d56832 bonus calculation for prior countermoves
Introduce a new term to the bonus calculation for prior countermoves

Passed STC:
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 140896 W: 36545 L: 36079 D: 68272
Ptnml(0-2): 383, 16505, 36217, 16949, 394
https://tests.stockfishchess.org/tests/view/6691c73cc6827afcdcee1816

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 126660 W: 32089 L: 31587 D: 62984
Ptnml(0-2): 63, 13774, 35154, 14276, 63
https://tests.stockfishchess.org/tests/view/6691cdc4c6827afcdcee1930

closes https://github.com/official-stockfish/Stockfish/pull/5483

bench: 1250388
2024-07-15 13:27:42 +02:00
Linmiao Xu
558abdbe8a Set best value to futility value after pruned quiet move
Passed non-regression STC:
https://tests.stockfishchess.org/tests/view/6691592f5034141ae599c68d
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 278496 W: 71818 L: 71865 D: 134813
Ptnml(0-2): 865, 33311, 70978, 33194, 900

Passed non-regression LTC:
https://tests.stockfishchess.org/tests/view/66918fca5034141ae599e761
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 202986 W: 51048 L: 51013 D: 100925
Ptnml(0-2): 107, 22552, 56133, 22601, 100

closes https://github.com/official-stockfish/Stockfish/pull/5480

bench 1715206
2024-07-15 13:24:14 +02:00
Michael Chaly
930915de90 Decrease delta
Decrease delta in aspiration windows - both initial value and quadratic
function of previous best value.

Passed STC:
https://tests.stockfishchess.org/tests/view/6691a52ec6827afcdcee1569
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 55456 W: 14449 L: 14107 D: 26900
Ptnml(0-2): 174, 6416, 14193, 6784, 161

Passed LTC:
https://tests.stockfishchess.org/tests/view/6691aac1c6827afcdcee1625
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 107940 W: 27530 L: 27065 D: 53345
Ptnml(0-2): 52, 11787, 29840, 12226, 65

closes https://github.com/official-stockfish/Stockfish/pull/5479

bench 1547707
2024-07-15 13:22:31 +02:00
MinetaS
563d268519 Simplify futility_move_count
This patch reverts changes from #4032 which was introduced as a speedup.
Modern compilers no longer use DIV/IDIV instructions, potentially making
the explicit branch perform worse. Since evaluations spend significantly
more time now, the impact of the speedup in search diminishes with old
compilers as well.

GCC 14.1.0 profile-build, x86-64-vnni512
```
.text:000000014010FEA9                 mov     ecx, [rsp+3FB8h+var_3F5C]
...
.text:000000014010FEBD                 mov     r10d, ecx
.text:000000014010FEC0                 imul    r10d, ecx
.text:000000014010FEC4                 mov     ecx, dword ptr [rsp+3FB8h+var_3F44+4]
.text:000000014010FEC8                 add     r10d, 3
.text:000000014010FECC                 mov     r11d, r10d
.text:000000014010FECF                 sar     r11d, 1
.text:000000014010FED2                 cmp     [rsp+3FB8h+var_3EE7], 0
.text:000000014010FEDA                 cmovnz  r11d, r10d
```

LLVM 18.1.18 profile-build, x86-64-vnni512
```
.text:0000000140001EDC                 mov     [rsp+40h+arg_E0], r13
.text:0000000140001EE4                 movsxd  rcx, r13d
.text:0000000140001EE7                 mov     rax, rcx
.text:0000000140001EEA                 mov     [rsp+40h+arg_B8], rcx
.text:0000000140001EF2                 imul    eax, eax
.text:0000000140001EF5                 add     eax, 3
.text:0000000140001EF8                 mov     ecx, [rsp+40h+arg_8C]
.text:0000000140001EFF                 shrx    eax, eax, ecx
.text:0000000140001F04                 mov     [rsp+40h+arg_190], rax
```

Passed non-regression STC:
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 109504 W: 28420 L: 28280 D: 52804
Ptnml(0-2): 355, 12326, 29273, 12420, 378
https://tests.stockfishchess.org/tests/view/6690dc095034141ae599c5fe

closes https://github.com/official-stockfish/Stockfish/pull/5478

No functional change
2024-07-15 13:19:46 +02:00
yl25946
8d1e41458e removed second killer move
STC with movepicker rewrite:

LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 46656 W: 12208 L: 11995 D: 22453
Ptnml(0-2): 203, 5461, 11777, 5694, 193
https://tests.stockfishchess.org/tests/view/668d98a15034141ae5999e68

Earlier version passed STC:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 468896 W: 120999 L: 120054 D: 227843
Ptnml(0-2): 1207, 55209, 120639, 56218, 1175
https://tests.stockfishchess.org/tests/view/668b17d2cf91c430fca58630

Earlier version passed LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 550524 W: 139553 L: 139877 D: 271094
Ptnml(0-2): 333, 61646, 151616, 61346, 321
https://tests.stockfishchess.org/tests/view/668b2e04cf91c430fca586b1

closes https://github.com/official-stockfish/Stockfish/pull/5472

bench 1234309

Co-authored-by: rn5f107s2 <clemens.lerchl@gmail.com>
2024-07-11 07:29:49 +02:00
Stéphane Nicolet
7e72b37e4c Clean up comments in code
- Capitalize comments
- Reformat multi-lines comments to equalize the widths of the lines
- Try to keep the width of comments around 85 characters
- Remove periods at the end of single-line comments

closes https://github.com/official-stockfish/Stockfish/pull/5469

No functional change
2024-07-11 07:29:33 +02:00
yl25946
362a77a345 Move Loop Consistency in Probcut
In probcut move loop, everything is enclosed within a large if statement. I've
changed it to guard clauses to stay consistent with other move loops.

closes https://github.com/official-stockfish/Stockfish/pull/5463

No functional change
2024-07-09 18:54:12 +02:00
Shawn Xu
4880ed4ad1 Simplify Probcut Malus
Passed Non-regression STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 74880 W: 19261 L: 19083 D: 36536
Ptnml(0-2): 202, 8861, 19120, 9071, 186
https://tests.stockfishchess.org/tests/view/668a0966eca84f4d25864cba

Passed Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 263916 W: 66690 L: 66718 D: 130508
Ptnml(0-2): 125, 29348, 73040, 29320, 125
https://tests.stockfishchess.org/tests/view/668a17e3eca84f4d25864e91

closes https://github.com/official-stockfish/Stockfish/pull/5464

bench 1331408
2024-07-09 18:44:39 +02:00
Michael Chaly
eac2d080a3 Further simplify stat bonuses
Based on recent simplification by linrock Since it completely removed any
special bonuses based on values difference and made it flat stat_bonus(depth +
1) I got an idea that we might as well remove all (depth + 1) bonuses and make
them usual depth bonuses.  Also removes weird negative bonus for depth 1 as a
side effect.

Passed STC:
https://tests.stockfishchess.org/tests/view/6689d817eca84f4d25863746
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 18080 W: 4789 L: 4552 D: 8739
Ptnml(0-2): 46, 1987, 4727, 2244, 36

Passed LTC:
https://tests.stockfishchess.org/tests/view/6689daa4eca84f4d258639d7
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 109062 W: 27548 L: 27417 D: 54097
Ptnml(0-2): 58, 11983, 30293, 12164, 33

Passed direct LTC vs linrock patch:
https://tests.stockfishchess.org/tests/view/668a46f8eca84f4d25866fe9
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 100002 W: 25351 L: 25209 D: 49442
Ptnml(0-2): 54, 11119, 27529, 11229, 70

closes https://github.com/official-stockfish/Stockfish/pull/5461

Bench 1175744
2024-07-09 18:41:36 +02:00
Joost VandeVondele
5d3517c601 Fix output for GUI
Fritz 19 can hang with the current way to provide output,
i.e. too much output in a short time for a mate / depth 245 found quickly.

fallout from 25361e514b

closes https://github.com/official-stockfish/Stockfish/pull/5460

No functional change
2024-07-09 18:36:46 +02:00
Linmiao Xu
4e9fded5a6 Larger bonus when updating quiet stats
Also removes unused arguments to update_all_stats to
fix compiler warnings about unused parameters.

Passed non-regression STC:
https://tests.stockfishchess.org/tests/view/6689a79a0fdd852d63cf52e9
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 26496 W: 6901 L: 6669 D: 12926
Ptnml(0-2): 62, 3094, 6715, 3304, 73

Passed non-regression LTC:
https://tests.stockfishchess.org/tests/view/6689a9960fdd852d63cf532d
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 41214 W: 10373 L: 10173 D: 20668
Ptnml(0-2): 11, 4491, 11412, 4673, 20

closes https://github.com/official-stockfish/Stockfish/pull/5456

bench 1169958
2024-07-09 18:31:02 +02:00
Michael Chaly
75c8cb2c2f Adjust usage of previous statscore in bonus assignments
This patch adjusts usage of previous statscore for bonus assginments - allowing
it for any statscores and clamping it to wider range.

Passed STC:
https://tests.stockfishchess.org/tests/view/66892e76e59d990b103f6a91
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 431520 W: 111767 L: 110872 D: 208881
Ptnml(0-2): 1180, 51165, 110133, 52144, 1138

Passed LTC:
https://tests.stockfishchess.org/tests/view/66897176e59d990b103f9605
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 143184 W: 36463 L: 35929 D: 70792
Ptnml(0-2): 55, 15540, 39863, 16084, 50

closes https://github.com/official-stockfish/Stockfish/pull/5455

bench 1330556
2024-07-09 18:29:09 +02:00
Linmiao Xu
bb9b65408f Simplify improving deduction in futility margin
Passed non-regression STC:
https://tests.stockfishchess.org/tests/view/668981d4df142e108ffc9bb4
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 312672 W: 80280 L: 80363 D: 152029
Ptnml(0-2): 729, 37198, 80529, 37187, 693

Passed non-regression LTC:
https://tests.stockfishchess.org/tests/view/668988c6df142e108ffca042
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 126042 W: 31971 L: 31857 D: 62214
Ptnml(0-2): 50, 13988, 34832, 14100, 51

closes https://github.com/official-stockfish/Stockfish/pull/5454

bench 1100483
2024-07-09 18:28:06 +02:00
Shawn Xu
2d3ef434b4 Tweak LMR at Root
Passed STC:
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 328192 W: 84751 L: 84014 D: 159427
Ptnml(0-2): 758, 38802, 84253, 39511, 772
https://tests.stockfishchess.org/tests/view/6689203959cb3228a4759a49

Passed LTC:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 56748 W: 14494 L: 14136 D: 28118
Ptnml(0-2): 19, 6089, 15803, 6441, 22
https://tests.stockfishchess.org/tests/view/66892d76e59d990b103f6626

closes https://github.com/official-stockfish/Stockfish/pull/5452

Bench 1253593
2024-07-09 18:26:35 +02:00
Shawn Xu
b79ac764ff Simplify in-check condition for Probcut-in-check
dont let your memes be dreams !?

Passed Non-regression STC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 512000 W: 132193 L: 132497 D: 247310
Ptnml(0-2): 1600, 61170, 130704, 60986, 1540
https://tests.stockfishchess.org/tests/view/66838911c4f539faa03268a2

Passed Non-regression LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 380268 W: 95894 L: 96042 D: 188332
Ptnml(0-2): 193, 42861, 104180, 42701, 199
https://tests.stockfishchess.org/tests/view/6688d0550c9d7c1ab33ed5a8

closes https://github.com/official-stockfish/Stockfish/pull/5443

Bench: 1130282
2024-07-09 18:24:40 +02:00
Shawn Xu
b1f522930d Simplify Away Move Count Pruning Adjustment
Using Singular Search Result

Passed Non-regression STC:
LLR: 3.01 (-2.94,2.94) <-1.75,0.25>
Total: 62688 W: 16319 L: 16121 D: 30248
Ptnml(0-2): 196, 7317, 16104, 7547, 180
https://tests.stockfishchess.org/tests/view/66879bf51b527f04dd477ff9

Passed Non-regression LTC:
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 116502 W: 29504 L: 29379 D: 57619
Ptnml(0-2): 66, 12881, 32226, 13018, 60
https://tests.stockfishchess.org/tests/view/6688629e0c9d7c1ab33ed030

closes https://github.com/official-stockfish/Stockfish/pull/5442

bench 1207930
2024-07-09 18:20:26 +02:00
Muzhen Gaming
4d6e1225bd Simplify ttPv reduction formula
This is a revert of 2046c92.
This patch is based on the fact that the ttPv reduction has proven non-linear scaling (as documented in the code, along with testing guidelines); however, the original patch had (erroneously) not been tested at VLTC or longer.

Simplification STC: https://tests.stockfishchess.org/tests/view/6689266e59cb3228a4759b28
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 100320 W: 25913 L: 25763 D: 48644
Ptnml(0-2): 270, 11842, 25750, 12064, 234

Simplification LTC: https://tests.stockfishchess.org/tests/view/66893103e59d990b103f6ab3
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 57078 W: 14466 L: 14282 D: 28330
Ptnml(0-2): 34, 6214, 15851, 6414, 26

closes https://github.com/official-stockfish/Stockfish/pull/5448

Bench: 1124658
2024-07-06 18:00:09 +02:00
Muzhen Gaming
55cb235d47 Simplify internal iterative reductions
This is a revert of cc992e5.
This patch is based on consistent observations that decreasing depth more in IIR generally has a bad scaling behaviour (good at STC, bad at longer time controls).

Simplification STC: https://tests.stockfishchess.org/tests/view/6689266659cb3228a4759b26
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 96992 W: 24977 L: 24824 D: 47191
Ptnml(0-2): 251, 11497, 24851, 11642, 255

Simplification LTC: https://tests.stockfishchess.org/tests/view/668930ffe59d990b103f6ab1
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 35808 W: 9185 L: 8980 D: 17643
Ptnml(0-2): 25, 3776, 10101, 3973, 29

closes https://github.com/official-stockfish/Stockfish/pull/5447

Bench: 1097766
2024-07-06 17:58:23 +02:00
Shawn Xu
24ab46c511 Non-functional Fixes & Updates
Fixes a missing default slot for dbg_extremes of, removes a extra newline, and
updates SE elo estimate from
https://tests.stockfishchess.org/tests/view/664ebd1e928b1fb18de4e4b7 while we
are at it.

closes https://github.com/official-stockfish/Stockfish/pull/5446

No functional change
2024-07-06 17:56:31 +02:00
FauziAkram
ec8288fe0d Simplify away eval in TM
Passed STC:
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 40160 W: 10523 L: 10309 D: 19328
Ptnml(0-2): 129, 4543, 10524, 4753, 131
https://tests.stockfishchess.org/tests/view/6685ab8b99271ae49479dbe9

Passed LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 195672 W: 49681 L: 49639 D: 96352
Ptnml(0-2): 112, 20976, 55597, 21060, 91
https://tests.stockfishchess.org/tests/view/6686f27a7092ade1206f7889

closes https://github.com/official-stockfish/Stockfish/pull/5445

No functional change
2024-07-06 17:54:22 +02:00
Shawn Xu
a45c2bc34a Simplify Away Countermove Heuristic
Passed Non-regression STC:
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 977824 W: 252072 L: 252888 D: 472864
Ptnml(0-2): 2518, 117120, 250560, 116088, 2626
https://tests.stockfishchess.org/tests/view/6683452d95b0d1e881e81541

Passed Non-regression LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 81048 W: 20630 L: 20470 D: 39948
Ptnml(0-2): 36, 8915, 22464, 9071, 38
https://tests.stockfishchess.org/tests/view/66886b7b0c9d7c1ab33ed281

closes https://github.com/official-stockfish/Stockfish/pull/5441

bench 1276784
2024-07-06 17:48:11 +02:00
Muzhen Gaming
daa9e217ab VVLTC search tune
Passed VVLTC 1st sprt: https://tests.stockfishchess.org/tests/view/6688af640c9d7c1ab33ed327
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 16050 W: 4200 L: 3959 D: 7891
Ptnml(0-2): 0, 1383, 5018, 1624, 0

Passed VVLTC 2nd sprt: https://tests.stockfishchess.org/tests/view/6688e8900c9d7c1ab33efd60
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 44044 W: 11303 L: 10999 D: 21742
Ptnml(0-2): 1, 3973, 13772, 4273, 3

closes https://github.com/official-stockfish/Stockfish/pull/5444

Bench: 992058
2024-07-06 17:45:58 +02:00
Joost VandeVondele
2cbc20e846 Correct and extend PV lines with decisive TB score
Currently (after #5407), SF has the property that any PV line with a decisive
TB score contains the corresponding TB position, with a score that correctly
identifies the depth at which TB are entered. The PV line that follows might
not preserve the game outcome, but can easily be verified and extended based on
TB information. This patch provides this functionality, simply extending the PV
lines on output, this doesn't affect search.

Indeed, if DTZ tables are available, search based PV lines that correspond to
decisive TB scores are verified to preserve game outcome, truncating the line
as needed. Subsequently, such PV lines are extended with a game outcome
preserving line until mate, as a possible continuation.  These lines are not
optimal mating lines, but are similar to what a user could produce on a website
like https://syzygy-tables.info/ clicking always the top ranked move, i.e.
minimizing or maximizing DTZ (with a simple tie-breaker for moves that have
identical DTZ), and are thus an just an illustration of how to game can be won.

A similar approach is already in established in
https://github.com/joergoster/Stockfish/tree/matefish2

This also contributes to addressing #5175 where SF can give an incorrect TB
win/loss for positions in TB with a movecounter that doesn't reflect optimal
play. While the full solution requires either TB generated differently, or a
search when ranking rootmoves, current SF will eventually find a draw in these
cases, in practice quite quickly, e.g.
`1kq5/q2r4/5K2/8/8/8/8/7Q w - - 96 1`
`8/8/6k1/3B4/3K4/4N3/8/8 w - - 54 106`

Gives the same results as master on an extended set of test positions from
9173d29c41
with the exception of the above mentioned fen where this commit improves.

With https://github.com/vondele/matetrack using 6men TB, all generated PVs verify:
```
Using ../Stockfish/src/stockfish.syzygyExtend on matetrack.epd with --nodes 1000000 --syzygyPath /chess/syzygy/3-4-5-6/WDL:/chess/syzygy/3-4-5-6/DTZ
Engine ID:     Stockfish dev-20240704-ff227954
Total FENs:    6555
Found mates:   3299
Best mates:    2582
Found TB wins: 568
```

As repeated DTZ probing could be slow a procedure (100ms+ on HDD, a few ms on
SSD), the extension is only done as long as the time taken is less than half
the `Move Overhead` parameter. For tournaments where these lines might be of
interest to the user, a suitable `Move Overhead` might be needed (e.g. TCEC has
1000ms already).

closes https://github.com/official-stockfish/Stockfish/pull/5414

No functional change
2024-07-05 15:43:49 +02:00
Linmiao Xu
3c379e55d9 Update 7 stat bonus/malus params
Values found around 119k / 120k spsa games at 60+0.6:
https://tests.stockfishchess.org/tests/view/6683112a192114e61f92f87a

Passed STC:
https://tests.stockfishchess.org/tests/view/66838148c4f539faa0326897
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 40928 W: 10835 L: 10508 D: 19585
Ptnml(0-2): 139, 4802, 10254, 5131, 138

Passed LTC:
https://tests.stockfishchess.org/tests/view/668448a87a1863935cee42c6
LLR: 2.96 (-2.94,2.94) <0.50,2.50>
Total: 29208 W: 7559 L: 7253 D: 14396
Ptnml(0-2): 17, 3118, 8019, 3442, 8

closes https://github.com/official-stockfish/Stockfish/pull/5439

bench 1138753
2024-07-05 15:43:49 +02:00
Joost VandeVondele
25361e514b Output from a fix depth onward, instead of 3s.
To avoid output that depends on timing, output currmove and similar only from depth > 30
onward.  Current choice of 3s makes the output of the same search depending on
the system load, and doesn't always start at move 1. Depth 30 is nowadays
reached in a few seconds on most systems.

closes https://github.com/official-stockfish/Stockfish/pull/5436

No functional change
2024-07-05 15:43:42 +02:00
Shahin M. Shahin
6b7822119f Limit has_game_cycle() to only upcoming repetition
use the original algorithm according to the paper
http://web.archive.org/web/20201107002606/https://marcelk.net/2013-04-06/paper/upcoming-rep-v2.pdf,
which detects accurately if a position has an upcoming repetition. The 'no
progress' part of has_game_cycle has been removed, the function has been
renamed to upcoming_repetition to reflect this.

As a result of this fix, to the best of our knowledge, all PVs for completed
iterations that yield a mate or decisive table base score now end in mate or
contain a TB position, respectively.

passed non-regression STC:
https://tests.stockfishchess.org/tests/view/6679fa1d0c2db3fa2dcecbf2
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 63584 W: 16666 L: 16472 D: 30446
Ptnml(0-2): 186, 7552, 16146, 7698, 210

Passed non-regression LTC:
https://tests.stockfishchess.org/tests/view/667ac965e439ed1c7a9ca042
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 464574 W: 117493 L: 117729 D: 229352
Ptnml(0-2): 311, 52468, 126974, 52214, 320

closes https://github.com/official-stockfish/Stockfish/pull/5432

bench: 1209805
2024-07-03 13:35:49 +02:00
Shawn Xu
69ad4667fb Do Capture History Updates In Probcut
This patch introduces history updates to probcut. Standard depth - 3 bonus and
maluses are given to the capture that caused fail high and previously searched
captures, respectively. Similar to #5243, a negative history fill is applied to
compensate for an increase in capture history average, thus improving the
scaling of this patch.

Passed STC:
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 84832 W: 21941 L: 21556 D: 41335
Ptnml(0-2): 226, 9927, 21688, 10386, 189
https://tests.stockfishchess.org/tests/view/6682fab9389b9ee542b1d029

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 104298 W: 26469 L: 26011 D: 51818
Ptnml(0-2): 43, 11458, 28677, 11940, 31
https://tests.stockfishchess.org/tests/view/6682ff06389b9ee542b1d0a0

closes https://github.com/official-stockfish/Stockfish/pull/5428

bench 1281351
2024-07-03 13:18:00 +02:00
Dubslow
6138a0fd0e Probcut in check no matter if pv or capture
Passed STC: https://tests.stockfishchess.org/tests/view/6681e9c8c1657e386d294cef
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 217824 W: 56149 L: 56129 D: 105546
Ptnml(0-2): 587, 25926, 55848, 25982, 569

Passed LTC: https://tests.stockfishchess.org/tests/view/6681fcb8c1657e386d294db1
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 357552 W: 90546 L: 90671 D: 176335
Ptnml(0-2): 207, 40064, 98362, 39933, 210

Each half of this also passed STC+LTC separately

closes https://github.com/official-stockfish/Stockfish/pull/5427

bench 1227870
2024-07-01 20:07:03 +02:00
Linmiao Xu
843b6f7c98 Update some params for pruning at shallow depth
Values found around 82k / 120k spsa games at 60+0.6:
https://tests.stockfishchess.org/tests/view/6681aca4481148df247298bd

Passed STC:
https://tests.stockfishchess.org/tests/view/6681c795c1657e386d2948fa
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 145216 W: 37595 L: 37122 D: 70499
Ptnml(0-2): 375, 17122, 37185, 17507, 419

Passed LTC:
https://tests.stockfishchess.org/tests/view/6681d4eec1657e386d2949e0
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 154062 W: 39117 L: 38557 D: 76388
Ptnml(0-2): 67, 16874, 42608, 17396, 86

closes https://github.com/official-stockfish/Stockfish/pull/5425

bench 996419
2024-07-01 20:04:13 +02:00
Linmiao Xu
f6842a145c Simplify worsening deduction in futility margin
Passed non-regression STC:
https://tests.stockfishchess.org/tests/view/66817d46442423e547141226
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 345408 W: 89146 L: 89266 D: 166996
Ptnml(0-2): 954, 41317, 88286, 41189, 958

Passed non-regression LTC:
https://tests.stockfishchess.org/tests/view/66818dbe1e90a146232d1f62
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 173214 W: 43821 L: 43755 D: 85638
Ptnml(0-2): 108, 19407, 47492, 19511, 89

closes https://github.com/official-stockfish/Stockfish/pull/5424

bench 981017
2024-07-01 20:02:38 +02:00
FauziAkram
5deb262393 Simplify rm.averageScore calculation
Passed STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 485056 W: 125222 L: 125497 D: 234337
Ptnml(0-2): 1384, 58197, 123614, 57976, 1357
https://tests.stockfishchess.org/tests/view/6681816d442423e54714133f

Passed LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 56622 W: 14301 L: 14115 D: 28206
Ptnml(0-2): 31, 6259, 15538, 6459, 24
https://tests.stockfishchess.org/tests/view/6681a9a5596d543edc677490

closes https://github.com/official-stockfish/Stockfish/pull/5423

bench: 1171203
2024-07-01 20:01:05 +02:00
Shahin M. Shahin
38c5fc33e4 Increase reduction based on correct expectation
If the current node is not a cutNode then it means that the child is one in LMR
and the cutoff count is expected, so more reduction when the cutoffs are
expected

Passed STC:
https://tests.stockfishchess.org/tests/view/66815e791c5b344a34ca7090
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 64416 W: 16876 L: 16519 D: 31021
Ptnml(0-2): 150, 7670, 16264, 7921, 203

Passed LTC:
https://tests.stockfishchess.org/tests/view/668162f61c5b344a34ca725c
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 78186 W: 19905 L: 19499 D: 38782
Ptnml(0-2): 55, 8561, 21437, 9003, 37

closes https://github.com/official-stockfish/Stockfish/pull/5422

bench: 1161531
2024-07-01 19:58:13 +02:00
Michael Chaly
7b49f9dd70 Tweak multicut
This patch is an original patch by author of Altair
(https://github.com/Alex2262/AltairChessEngine) chess engine.

It allows to produce more aggressive multicut compared to master by changing
condition it needs to fulfil and also returns bigger value.  Also has applied
matetrack fix on top.

Passed STC:
https://tests.stockfishchess.org/tests/view/667223ab602682471b0650e2
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 50048 W: 13200 L: 12860 D: 23988
Ptnml(0-2): 181, 5822, 12679, 6160, 182

Passed LTC:
https://tests.stockfishchess.org/tests/view/6672f777602682471b06515d
LLR: 2.97 (-2.94,2.94) <0.50,2.50>
Total: 706380 W: 179707 L: 177981 D: 348692
Ptnml(0-2): 656, 79250, 191665, 80950, 669

closes https://github.com/official-stockfish/Stockfish/pull/5421

bench 1148966
2024-07-01 19:56:38 +02:00
Daniel Monroe
91ec31dac4 Grade countermove bonus for low statscores
Passed STC:
LLR: 2.96 (-2.94,2.94) <0.00,2.00>
Total: 338592 W: 88396 L: 87627 D: 162569
Ptnml(0-2): 1161, 40201, 85788, 41000, 1146
https://tests.stockfishchess.org/tests/view/6679d40c0c2db3fa2dcecbcc

Passed LTC:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 83526 W: 21429 L: 21010 D: 41087
Ptnml(0-2): 54, 9173, 22913, 9546, 77
https://tests.stockfishchess.org/tests/view/667c5f2980450dba965911fc

closes https://github.com/official-stockfish/Stockfish/pull/5418

bench: 1489815
2024-07-01 19:53:45 +02:00
Taras Vuk
22a502ac74 Skip futility pruning if beta is below TB loss value
Passed STC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 77024 W: 20122 L: 19946 D: 36956
Ptnml(0-2): 278, 8754, 20277, 8920, 283
https://tests.stockfishchess.org/tests/view/66752d59602682471b0652f3

Passed LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 93114 W: 23623 L: 23477 D: 46014
Ptnml(0-2): 77, 9839, 26566, 10011, 64
https://tests.stockfishchess.org/tests/view/6676b3e1602682471b065395

closes https://github.com/official-stockfish/Stockfish/pull/5413

bench: 1003441
2024-07-01 19:48:06 +02:00
FauziAkram
cc992e5e4a Internal iterative reductions: decrease depth more
For PV nodes without a ttMove, we decrease depth.
But in this patch, additionally, if the current position is found in the TT, and the stored depth in the TT is greater than or equal to
the current search depth, we decrease the search depth even further.

Passed STC:
LLR: 2.96 (-2.94,2.94) <0.00,2.00>
Total: 84384 W: 22154 L: 21761 D: 40469
Ptnml(0-2): 292, 9972, 21315, 10277, 336
https://tests.stockfishchess.org/tests/view/666b0a4d602682471b064db6

Passed LTC:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 92106 W: 23471 L: 23032 D: 45603
Ptnml(0-2): 79, 10155, 25154, 10578, 87
https://tests.stockfishchess.org/tests/view/666c423d602682471b064e56

closes https://github.com/official-stockfish/Stockfish/pull/5397

bench: 1038234
2024-06-23 11:46:41 +02:00
Shawn Xu
d5c130569b Simplify Bonus Formula In History Adjustment
Inspired by a discord message [1] from Vizvezdenec, this patch simplifies the
bonus adjustment bonus = bonus > 0 ? 2 * bonus : bonus / 2 to a constant
addition, maintaining bonus average at around 0 in regular bench. As cj5716
pointed in discord [2], the constant bonus can also be considered as factoring
tempo when calculating bonus, yielding a better value of the move.

[1] https://discord.com/channels/435943710472011776/882956631514689597/1243877089443188776
[2] https://discord.com/channels/435943710472011776/813919248455827515/1252277437249622077

Passed Non-regression STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 29984 W: 7908 L: 7677 D: 14399
Ptnml(0-2): 95, 3502, 7594, 3679, 122
https://tests.stockfishchess.org/tests/view/666f7210602682471b064fa2

Passed Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 170136 W: 43214 L: 43145 D: 83777
Ptnml(0-2): 158, 19185, 46311, 19258, 156
https://tests.stockfishchess.org/tests/view/666fb32e602682471b064fb5

closes https://github.com/official-stockfish/Stockfish/pull/5401

bench 1438375
2024-06-23 11:41:48 +02:00
evqsx
8806a58ebf Simplify static exchange evaluation pruning formula
Passed STC: https://tests.stockfishchess.org/tests/view/666bda31602682471b064e1f
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 141696 W: 36932 L: 36826 D: 67938
Ptnml(0-2): 510, 16880, 35989, 16932, 537

Passed LTC: https://tests.stockfishchess.org/tests/view/666e6b67602682471b064f4b
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 159504 W: 40552 L: 40471 D: 78481
Ptnml(0-2): 130, 18160, 43103, 18217, 142

closes https://github.com/official-stockfish/Stockfish/pull/5400

bench: 1084115
2024-06-23 11:37:32 +02:00
xoto10
2678606e8d Consider wider range of moves near leaves.
try to avoid missing good moves for opponent or engine, by updating bestMove
also when value == bestValue (i.e. value == alpha) under certain conditions.
In particular require this is at higher depth in the tree, leaving the logic
near the root unchanged, and only apply randomly. Avoid doing this near mate
scores, leaving mate PVs intact.

Passed SMP STC 6+0.06 th7 :
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 42040 W: 10930 L: 10624 D: 20486
Ptnml(0-2): 28, 4682, 11289, 4998, 23
https://tests.stockfishchess.org/tests/view/66608b00c340c8eed7757d1d

Passed SMP LTC 24+0.24 th7 :
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 73692 W: 18978 L: 18600 D: 36114
Ptnml(0-2): 9, 7421, 21614, 7787, 15
https://tests.stockfishchess.org/tests/view/666095e8c340c8eed7757d49

closes https://github.com/official-stockfish/Stockfish/pull/5367

Bench 1205168
2024-06-23 11:29:02 +02:00
FauziAkram
2046c92ad4 Tweak the reduction formula
Tweak the reduction formula if position is or has been on the PV
Taking inspiration from an old Viren test.

Passed STC:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 78528 W: 20607 L: 20225 D: 37696
Ptnml(0-2): 262, 9297, 19785, 9637, 283
https://tests.stockfishchess.org/tests/view/666339c70ff7cb4868d1fe24

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 138630 W: 35666 L: 35132 D: 67832
Ptnml(0-2): 118, 15345, 37835, 15919, 98
https://tests.stockfishchess.org/tests/view/66645dec0612cd151f9e77b0

closes https://github.com/official-stockfish/Stockfish/pull/5385

Bench: 1134281
2024-06-15 12:13:59 +02:00
Joost VandeVondele
b01fdb596a Fix upperbound/lowerbound output in multithreaded case
In case a stop is received during multithreaded searches, the PV of the best
thread might be printed without the correct upperbound/lowerbound indicators.
This was due to the pvIdx variable being incremented after receiving the stop.

passed STC:
https://tests.stockfishchess.org/tests/view/666985da602682471b064d08
 LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 196576 W: 51039 L: 50996 D: 94541
Ptnml(0-2): 760, 22545, 51603, 22652, 728

closes https://github.com/official-stockfish/Stockfish/pull/5391

Bench: 1160467
2024-06-15 12:08:29 +02:00
Joost VandeVondele
3d92950859 Limit depth after extensions to avoid asserts.
currently extensions can cause depth to exceed MAX_PLY.

This triggers the assert near line 542 in search when running a binary compiled with `debug=yes` on a testcase like:
```
position fen 7K/P1p1p1p1/2P1P1Pk/6pP/3p2P1/1P6/3P4/8 w - - 0 1
go nodes 1000000
```

passed STC
https://tests.stockfishchess.org/tests/view/6668a56a602682471b064c8d
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 143936 W: 37338 L: 37238 D: 69360
Ptnml(0-2): 514, 16335, 38149, 16477, 493

closes https://github.com/official-stockfish/Stockfish/pull/5383

Bench: 1160467
2024-06-15 12:02:56 +02:00
Dubslow
c8213ba0d0 Simplify TT interface and avoid changing TT info
This commit builds on the work and ideas of #5345, #5348, and #5364.

Place as much as possible of the TT implementation in tt.cpp, rather than in the
header.  Some commentary is added to better document the public interface.

Fix the search read-TT races, or at least contain them to within TT methods only.

Passed SMP STC: https://tests.stockfishchess.org/tests/view/666134ab91e372763104b443
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 512552 W: 132387 L: 132676 D: 247489
Ptnml(0-2): 469, 58429, 138771, 58136, 471

The unmerged version has bench identical to the other PR (see also #5348) and
therefore those same-functionality tests:

SMP LTC: https://tests.stockfishchess.org/tests/view/665c7021fd45fb0f907c214a
SMP LTC: https://tests.stockfishchess.org/tests/view/665d28a7fd45fb0f907c5495

closes https://github.com/official-stockfish/Stockfish/pull/5369

bench 1205675
2024-06-12 09:17:04 +02:00
Joost VandeVondele
7e890fd048 Keep mate PVs intact.
do not return a cutoff value in razoring if that value is in the mate/tb range.

passed STC:
https://tests.stockfishchess.org/tests/view/666381880ff7cb4868d1fe58
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 130848 W: 34046 L: 33931 D: 62871
Ptnml(0-2): 429, 14968, 34524, 15065, 438

passed LTC:
https://tests.stockfishchess.org/tests/view/66643f120612cd151f9e7788
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 39702 W: 10157 L: 9959 D: 19586
Ptnml(0-2): 20, 4108, 11402, 4296, 25

closes https://github.com/official-stockfish/Stockfish/pull/5379

Bench: 1174094
2024-06-12 09:03:32 +02:00
evqsx
4151c06b74 Remove the correction history bonus in null move search
Passed STC:
https://tests.stockfishchess.org/tests/view/666168e191e372763104c664
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 94848 W: 24708 L: 24550 D: 45590
Ptnml(0-2): 289, 11355, 24033, 11403, 344

Passed LTC:
https://tests.stockfishchess.org/tests/view/6661e73591e372763104c751
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 70452 W: 17849 L: 17679 D: 34924
Ptnml(0-2): 27, 7707, 19596, 7861, 35

closes https://github.com/official-stockfish/Stockfish/pull/5375

Bench: 1174094
2024-06-08 23:39:46 +02:00