From: VoyagerOne Date: Mon, 13 Jul 2015 22:19:09 +0000 (-0400) Subject: LMR Simplification: Remove countermove condition X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=1d977aa79ecaf410f4b2065eb8f11e0a5e689db4;ds=sidebyside LMR Simplification: Remove countermove condition Removed countermove condition for decreasing reduction. LTC: LLR: 3.01 (-2.94,2.94) [-3.00,1.00] Total: 32410 W: 5092 L: 4986 D: 22332 STC: LLR: 2.95 (-2.94,2.94) [-3.00,1.00] Total: 24450 W: 4632 L: 4517 D: 15301 Bench: 6943812 Resolves #378 --- diff --git a/src/search.cpp b/src/search.cpp index 7eab970a..b9ff56fb 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -958,10 +958,9 @@ moves_loop: // When in check and at SpNode search starts from here [pos.piece_on(to_sq(move))][to_sq(move)] <= VALUE_ZERO)) ss->reduction += ONE_PLY; - if ( move == countermove - || ( History[pos.piece_on(to_sq(move))][to_sq(move)] > VALUE_ZERO + if ( History[pos.piece_on(to_sq(move))][to_sq(move)] > VALUE_ZERO && CounterMovesHistory[pos.piece_on(prevMoveSq)][prevMoveSq] - [pos.piece_on(to_sq(move))][to_sq(move)] > VALUE_ZERO)) + [pos.piece_on(to_sq(move))][to_sq(move)] > VALUE_ZERO) ss->reduction = std::max(DEPTH_ZERO, ss->reduction - ONE_PLY); // Decrease reduction for moves that escape a capture