Isolated pawns tweak
authorElbertoOne <lubvdberg@gmail.com>
Sun, 31 May 2020 14:39:03 +0000 (16:39 +0200)
committerJoost VandeVondele <Joost.VandeVondele@gmail.com>
Mon, 1 Jun 2020 15:27:29 +0000 (17:27 +0200)
commit8c3d9d996af7aa34f019785818eecbeb9338b95f
treeb19424ebca14a7e088f34c23f3498585494394a4
parent616eb60008308f686930c0c94116aab170398dc1
Isolated pawns tweak

Give opposed doubled isolated pawns only the Doubled penalty.
The other isolated pawns get the Isolated penalty and the WeakUnopposed penalty.
The popcount condition has been replaced with an opposed check,
which is non-functional, but probably gives a speed-up.

Passed STC (https://tests.stockfishchess.org/tests/view/5ed0f0f0042fa6d77c3552f5):
LLR: 2.96 (-2.94,2.94) {-0.50,1.50}
Total: 121832 W: 23562 L: 23195 D: 75075
Ptnml(0-2): 2092, 14064, 28313, 14279, 2168

LTC: (https://tests.stockfishchess.org/tests/view/5ed22e40042fa6d77c355387)
LLR: 2.96 (-2.94,2.94) {0.25,1.75}
Total: 103368 W: 13232 L: 12768 D: 77368
Ptnml(0-2): 693, 9484, 30919, 9842, 746

closes https://github.com/official-stockfish/Stockfish/pull/2706

Bench: 4085694
src/pawns.cpp