Introduce futility pruning for captures
authorVizvezdenec <Vizvezdenec@gmail.com>
Tue, 28 Apr 2020 23:40:16 +0000 (02:40 +0300)
committerJoost VandeVondele <Joost.VandeVondele@gmail.com>
Wed, 29 Apr 2020 15:35:48 +0000 (17:35 +0200)
commit4776dc0e126ed311f10f34bfa058a6c86e9d3ef1
treece43ba8245d767201ba100f9d375f3631ab44084
parentbb5589b829b79d7c60a820d4b1634dccbc4bbb3f
Introduce futility pruning for captures

The idea is somewhat similar to futility pruning for quiet moves -
if a late enough capture doesn't give check and the static eval is
much lower than alpha we can almost safely assume that this capture
wouldn't be a good move.

passed STC
https://tests.stockfishchess.org/tests/view/5ea8544b53a4548a0348ee5b
LLR: 2.95 (-2.94,2.94) {-0.50,1.50}
Total: 236040 W: 44420 L: 43894 D: 147726
Ptnml(0-2): 3830, 27202, 55496, 27596, 3896

passed LTC
https://tests.stockfishchess.org/tests/view/5ea87c842141237a731f0c7d
LLR: 2.95 (-2.94,2.94) {0.25,1.75}
Total: 81336 W: 10429 L: 10028 D: 60879
Ptnml(0-2): 589, 7356, 24404, 7703, 616

closes https://github.com/official-stockfish/Stockfish/pull/2651

bench 4405247
src/search.cpp