From 2f7723fd44d5184c205d31ac1ac5199359afb0d3 Mon Sep 17 00:00:00 2001 From: Joona Kiiski Date: Mon, 20 Jul 2009 15:47:05 +0300 Subject: [PATCH] Remove useless mate value special handling in null search After 1200 games (1CPU), time control 1+0: Mod vs Orig: +331 =564 -277 +16 ELO Signed-off-by: Marco Costalba --- src/search.cpp | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) diff --git a/src/search.cpp b/src/search.cpp index fb308424..252b4299 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -1249,14 +1249,7 @@ namespace { pos.undo_null_move(); - if (value_is_mate(nullValue)) - { - if (nullValue == value_mated_in(ply + 2)) - mateThreat = true; - - /* Do not return unproven mates */ - } - else if (nullValue >= beta) + if (nullValue >= beta) { if (depth < 6 * OnePly) return beta; @@ -1272,6 +1265,9 @@ namespace { // move which was reduced. If a connection is found, return a fail // low score (which will cause the reduced move to fail high in the // parent node, which will trigger a re-search with full depth). + if (nullValue == value_mated_in(ply + 2)) + mateThreat = true; + ss[ply].threatMove = ss[ply + 1].currentMove; if ( depth < ThreatDepth && ss[ply - 1].reduction -- 2.39.2