Latest abrok Development Version May 23 RD (SF The gift that keeps on giving

!! 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: Muzhen Gaming Date: Thu May 23 21:37:46 2024 +0200 Timestamp: 1716493066 VVLTC search tune Parameters were tuned in 2 stages: 1. 127k games at VVLTC: https://tests.stockfishchess.org/tests/view/6649f8dfb8fa20e74c39f52a. 2. 106k games at VVLTC: https://tests.stockfishchess.org/tests/view/664bfb77830eb9f886615a9d. Passed VVLTC 1st sprt: https://tests.stockfishchess.org/tests/view/664e8dd9928b1fb18de4e410 LLR: 2.94 (-2.94,2.94) <0.00,2.00> Total: 20466 W: 5340 L: 5093 D: 10033 Elo +4.19 Ptnml(0-2): 0, 1796, 6397, 2037, 3 Passed VVLTC 2nd sprt: https://tests.stockfishchess.org/tests/view/664eb4aa928b1fb18de4e47d LLR: 2.95 (-2.94,2.94) <0.50,2.50> Total: 15854 W: 4186 L: 3934 D: 7734 Elo +5.52 Ptnml(0-2): 1, 1367, 4938, 1621, 0 closes https://github.com/official-stockfish/Stockfish/pull/5286 Bench: 1558110 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: Thu May 23 21:37:46 2024 +0200 Timestamp: 1716493066 Remove material imbalance param when adjusting optimism Passed non-regression STC: https://tests.stockfishchess.org/tests/view/664d033d830eb9f886616aff LLR: 2.93 (-2.94,2.94) <-1.75,0.25> Total: 102144 W: 26283 L: 26135 D: 49726 Elo +0.50 Ptnml(0-2): 292, 12201, 25991, 12243, 345 Passed non-regression LTC: https://tests.stockfishchess.org/tests/view/664d5c00830eb9f886616cb3 LLR: 2.94 (-2.94,2.94) <-1.75,0.25> Total: 250032 W: 63022 L: 63036 D: 123974 Elo -0.02 Ptnml(0-2): 103, 27941, 68970, 27871, 131 closes https://github.com/official-stockfish/Stockfish/pull/5284 Bench: 1330940 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: Muzhen Gaming Date: Thu May 23 21:37:46 2024 +0200 Timestamp: 1716493066 Revert "Reduce When TTValue is Above Alpha" The patch regressed significantly at longer time controls. In particular, the `depth--` behavior was predicted to scale badly based on data from other variations of the patch. Passed VVLTC 1st sprt: https://tests.stockfishchess.org/tests/view/664d45cf830eb9f886616c7d LLR: 2.95 (-2.94,2.94) <0.00,2.00> Total: 51292 W: 13242 L: 12954 D: 25096 Elo +1.95 Ptnml(0-2): 5, 4724, 15896, 5020, 1 Passed VVLTC 2nd sprt: https://tests.stockfishchess.org/tests/view/664e641a928b1fb18de4e385 LLR: 2.94 (-2.94,2.94) <0.50,2.50> Total: 41884 W: 10933 L: 10634 D: 20317 Elo +2.48 Ptnml(0-2): 1, 3759, 13125, 4054, 3 closes https://github.com/official-stockfish/Stockfish/pull/5283 Bench: 1503815 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: cj5716 Date: Thu May 23 21:37:46 2024 +0200 Timestamp: 1716493066 Optimise pairwise multiplication This speedup was first inspired by a comment by @AndyGrant on my recent PR "If mullo_epi16 would preserve the signedness, then this could be used to remove 50% of the max operations during the halfkp-pairwise mat-mul relu deal." That got me thinking, because although mullo_epi16 did not preserve the signedness, mulhi_epi16 did, and so we could shift left and then use mulhi_epi16, instead of shifting right after the mullo. However, due to some issues with shifting into the sign bit, the FT weights and biases had to be multiplied by 2 for the optimisation to work. Speedup on "Arch=x86-64-bmi2 COMP=clang", courtesy of @Torom Result of 50 runs base (...es/stockfish) = 962946 +/- 1202 test (...ise-max-less) = 979696 +/- 1084 diff = +16750 +/- 1794 speedup = +0.0174 P(speedup > 0) = 1.0000 CPU: 4 x Intel(R) Core(TM) i7-6700K CPU @ 4.00GHz Hyperthreading: on Also a speedup on "COMP=gcc", courtesy of Torom once again Result of 50 runs base (...tockfish_gcc) = 966033 +/- 1574 test (...max-less_gcc) = 983319 +/- 1513 diff = +17286 +/- 2515 speedup = +0.0179 P(speedup > 0) = 1.0000 CPU: 4 x Intel(R) Core(TM) i7-6700K CPU @ 4.00GHz Hyperthreading: on Passed STC: LLR: 2.96 (-2.94,2.94) <0.00,2.00> Total: 67712 W: 17715 L: 17358 D: 32639 Elo +1.83 Ptnml(0-2): 225, 7472, 18140, 7759, 260 https://tests.stockfishchess.org/tests/view/664c1d75830eb9f886616906 closes https://github.com/official-stockfish/Stockfish/pull/5282 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: Thu May 23 21:30:33 2024 +0200 Timestamp: 1716492633 Simplify Away History Updates in Multicut Passed Non-regression STC: LLR: 2.93 (-2.94,2.94) <-1.75,0.25> Total: 44896 W: 11600 L: 11388 D: 21908 Elo +1.64 Ptnml(0-2): 140, 5230, 11532, 5370, 176 https://tests.stockfishchess.org/tests/view/664cee31830eb9f886616a80 Passed Non-regression LTC: LLR: 2.96 (-2.94,2.94) <-1.75,0.25> Total: 56832 W: 14421 L: 14234 D: 28177 Elo +1.14 Ptnml(0-2): 37, 6251, 15643, 6458, 27 https://tests.stockfishchess.org/tests/view/664cfd4e830eb9f886616aa6 closes https://github.com/official-stockfish/Stockfish/pull/5281 Bench: 1119412 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: Thu May 23 21:30:24 2024 +0200 Timestamp: 1716492624 Comment about re-evaluating positions While the smallNet bool is no longer used as of now, setting it to false upon re-evaluation represents the correct eval state. closes https://github.com/official-stockfish/Stockfish/pull/5279 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: Viren6 Date: Thu May 23 21:29:36 2024 +0200 Timestamp: 1716492576 Addition of new scaling comments This patch is intended to prevent patches like 9b90cd8 and the subsequent reversion e3c9ed7 from happening again. Scaling behaviour of the reduction adjustments in the non-linear scaling section have been proven to >8 sigma: STC: https://tests.stockfishchess.org/tests/view/6647b19f6dcff0d1d6b05d52 Elo: 4.28 ± 0.8 (95%) LOS: 100.0% Total: 200000 W: 52555 L: 50094 D: 97351 Elo +4.28 Ptnml(0-2): 573, 22628, 51248, 24867, 684 nElo: 8.35 ± 1.5 (95%) PairsRatio: 1.10 VLTC: https://tests.stockfishchess.org/tests/view/6647b1b06dcff0d1d6b05d54 Elo: -1.48 ± 1.0 (95%) LOS: 0.2% Total: 100000 W: 25009 L: 25436 D: 49555 Elo -1.48 Ptnml(0-2): 11, 10716, 28971, 10293, 9 nElo: -3.23 ± 2.2 (95%) PairsRatio: 0.96 The else if condition is moved to the non scaling section based on: https://tests.stockfishchess.org/tests/view/664567a193ce6da3e93b3232 (It has no proven scaling) General comment improvements and removal of a redundant margin condition have also been included. closes https://github.com/official-stockfish/Stockfish/pull/5266 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: Dubslow Date: Thu May 23 21:29:11 2024 +0200 Timestamp: 1716492551 Improve comments about DEPTH constants Also "fix" movepicker to allow depths between CHECKS and NO_CHECKS, which makes them easier to tweak (not that they get tweaked hardly ever) (This was more beneficial when there was a third stage to DEPTH_QS, but it's still an improvement now) closes https://github.com/official-stockfish/Stockfish/pull/5205 No functional change see source

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