Remove depth condition for pruning captures.
authorJoost VandeVondele <Joost.VandeVondele@gmail.com>
Tue, 12 Jun 2018 05:32:21 +0000 (07:32 +0200)
committerStéphane Nicolet <cassio@free.fr>
Wed, 13 Jun 2018 19:46:12 +0000 (21:46 +0200)
The SEE condition alone is sufficient.

passed STC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 109863 W: 24339 L: 24392 D: 61132
http://tests.stockfishchess.org/tests/view/5b1f5b000ebc5902ab9c8668

passed LTC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 23390 W: 4020 L: 3903 D: 15467
http://tests.stockfishchess.org/tests/view/5b1f94b40ebc5902ab9c8b5e

Closes https://github.com/official-stockfish/Stockfish/pull/1648

Bench: 4834747

src/search.cpp

index 3a80e16..c678cd5 100644 (file)
@@ -951,8 +951,7 @@ moves_loop: // When in check, search starts from here
                   && !pos.see_ge(move, Value(-35 * lmrDepth * lmrDepth)))
                   continue;
           }
-          else if (    depth < 7 * ONE_PLY // (~20 Elo)
-                   && !extension
+          else if (   !extension // (~20 Elo)
                    && !pos.see_ge(move, -Value(PawnValueEg * (depth / ONE_PLY))))
                   continue;
       }