From 7cd650f435715f73550d1f8031315e65b701d631 Mon Sep 17 00:00:00 2001 From: pb00067 Date: Wed, 17 May 2023 09:22:02 +0200 Subject: [PATCH] Simplify SEE verfication logic Passed STC https://tests.stockfishchess.org/tests/view/6461d51887f6567dd4df27d0 LLR: 2.94 (-2.94,2.94) <-1.75,0.25> Total: 177056 W: 47181 L: 47118 D: 82757 Ptnml(0-2): 456, 19381, 48792, 19442, 457 Passed LTC https://tests.stockfishchess.org/tests/view/64631a9287f6567dd4df4502 2.94 (-2.94,2.94) <-1.75,0.25> Total: 104346 W: 28062 L: 27935 D: 48349 Ptnml(0-2): 25, 10190, 31631, 10287, 40 closes https://github.com/official-stockfish/Stockfish/pull/4578 bench: 2903251 --- src/search.cpp | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/src/search.cpp b/src/search.cpp index 10844746..653cbf33 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -996,9 +996,7 @@ moves_loop: // When in check, search starts here // SEE based pruning (~11 Elo) if (!pos.see_ge(move, occupied, Value(-205) * depth)) { - if (depth < 2 - capture) - continue; - // Don't prune the move if opp. King/Queen/Rook gets a discovered attack during or after the exchanges + // Don't prune the move if opponent King/Queen/Rook gets a discovered attack during or after the exchanges Bitboard leftEnemies = pos.pieces(~us, KING, QUEEN, ROOK); Bitboard attacks = 0; occupied |= to_sq(move); @@ -1006,7 +1004,7 @@ moves_loop: // When in check, search starts here { Square sq = pop_lsb(leftEnemies); attacks = pos.attackers_to(sq, occupied) & pos.pieces(us) & occupied; - // Exclude Queen/Rook(s) which were already threatened before SEE (opp King can't be in check when it's our turn) + // Exclude Queen/Rook(s) which were already threatened before SEE (opponent King can't be in check when it's our turn) if (attacks && sq != pos.square(~us) && (pos.attackers_to(sq, pos.pieces()) & pos.pieces(us))) attacks = 0; } -- 2.39.2