From baf184e8d9e22c86407538ab4b4004f58e0e996d Mon Sep 17 00:00:00 2001 From: Joost VandeVondele Date: Mon, 13 Jan 2020 15:46:40 +0100 Subject: [PATCH] Tweak late move reductions at root More LMR at root, unless a fail low might happen. passed STC: LLR: 2.94 (-2.94,2.94) {-1.00,3.00} Total: 25428 W: 4960 L: 4789 D: 15679 Ptnml(0-2): 424, 2948, 5832, 3045, 460 http://tests.stockfishchess.org/tests/view/5e1c9afed12216a2857e6401 passed LTC: LLR: 2.94 (-2.94,2.94) {0.00,2.00} Total: 187423 W: 24253 L: 23599 D: 139571 Ptnml(0-2): 1284, 17437, 55536, 18085, 1292 http://tests.stockfishchess.org/tests/view/5e1ceb9975be933c8fe635a3 Closes https://github.com/official-stockfish/Stockfish/pull/2493 Bench: 5156767 --- src/search.cpp | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/search.cpp b/src/search.cpp index c1ed1f95..0eea4127 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -1115,7 +1115,7 @@ moves_loop: // When in check, search starts from here // Step 16. Reduced depth search (LMR, ~200 Elo). If the move fails high it will be // re-searched at full depth. if ( depth >= 3 - && moveCount > 1 + 2 * rootNode + && moveCount > 1 + rootNode + (rootNode && bestValue < alpha) && (!rootNode || thisThread->best_move_count(move) == 0) && ( !captureOrPromotion || moveCountPruning -- 2.39.2