Tweak LMR and killers
authorVizvezdenec <Vizvezdenec@gmail.com>
Tue, 16 Jul 2019 11:56:52 +0000 (14:56 +0300)
committerStéphane Nicolet <cassio@free.fr>
Thu, 25 Jul 2019 06:17:11 +0000 (08:17 +0200)
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

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

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

bench 3723147

src/search.cpp

index 2c2321ee9ca0bb5f48bd99b4fc068986a8d2a297..1fc0bf1e6c6455ea470ad7047d80c8a5d2e85ef5 100644 (file)
@@ -1144,6 +1144,9 @@ moves_loop: // When in check, search starts from here
               int bonus = value > alpha ?  stat_bonus(newDepth)
                                         : -stat_bonus(newDepth);
 
               int bonus = value > alpha ?  stat_bonus(newDepth)
                                         : -stat_bonus(newDepth);
 
+              if (move == ss->killers[0])
+                 bonus += bonus / 4;
+
               update_continuation_histories(ss, movedPiece, to_sq(move), bonus);
           }
       }
               update_continuation_histories(ss, movedPiece, to_sq(move), bonus);
           }
       }