From 4803d5772c120121dad6bad78cc2b6be5c24fb1f Mon Sep 17 00:00:00 2001 From: Marco Costalba Date: Wed, 11 Sep 2013 09:22:57 +0200 Subject: [PATCH] Extend checks more when below alpha Passed both short TC: LLR: 2.97 (-2.94,2.94) [-1.50,4.50] Total: 8739 W: 1830 L: 1698 D: 5211 And long TC: LLR: 2.96 (-2.94,2.94) [0.00,6.00] Total: 6716 W: 1238 L: 1101 D: 4377 bench: 4554576 --- src/search.cpp | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/search.cpp b/src/search.cpp index f64f55f0..4384b58d 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -837,7 +837,7 @@ moves_loop: // When in check and at SpNode search starts from here ext = ONE_PLY; else if (givesCheck && pos.see_sign(move) >= 0) - ext = inCheck || ss->staticEval < VALUE_ZERO ? ONE_PLY : ONE_PLY / 2; + ext = inCheck || ss->staticEval <= alpha ? ONE_PLY : ONE_PLY / 2; // Singular extension search. If all moves but one fail low on a search of // (alpha-s, beta-s), and just one fails high on (alpha, beta), then that move -- 2.39.2