From 3346ccc9d965e13689ff4af12b2ea2433651890a Mon Sep 17 00:00:00 2001 From: Marco Costalba Date: Mon, 20 Dec 2010 16:42:07 +0100 Subject: [PATCH] Retire LMR intermediate research It does not seem to improve anything. After 8344 games Mod - Orig: 1362 - 1321 - 5661 ELO +2 Signed-off-by: Marco Costalba --- src/search.cpp | 25 ------------------------- 1 file changed, 25 deletions(-) diff --git a/src/search.cpp b/src/search.cpp index 92e7273b..95a516d7 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -828,18 +828,6 @@ namespace { value = -search(pos, ss+1, -(alpha+1), -alpha, newDepth-ss->reduction, 1); doFullDepthSearch = (value > alpha); } - - // The move failed high, but if reduction is very big we could - // face a false positive, retry with a less aggressive reduction, - // if the move fails high again then go with full depth search. - if (doFullDepthSearch && ss->reduction > 2 * ONE_PLY) - { - assert(newDepth - ONE_PLY >= ONE_PLY); - - ss->reduction = ONE_PLY; - value = -search(pos, ss+1, -(alpha+1), -alpha, newDepth-ss->reduction, 1); - doFullDepthSearch = (value > alpha); - } ss->reduction = DEPTH_ZERO; // Restore original reduction } @@ -1347,19 +1335,6 @@ split_point_start: // At split points actual search starts from here doFullDepthSearch = (value > alpha); } - - // The move failed high, but if reduction is very big we could - // face a false positive, retry with a less aggressive reduction, - // if the move fails high again then go with full depth search. - if (doFullDepthSearch && ss->reduction > 2 * ONE_PLY) - { - assert(newDepth - ONE_PLY >= ONE_PLY); - - ss->reduction = ONE_PLY; - alpha = SpNode ? sp->alpha : alpha; - value = -search(pos, ss+1, -(alpha+1), -alpha, newDepth-ss->reduction, ply+1); - doFullDepthSearch = (value > alpha); - } ss->reduction = DEPTH_ZERO; // Restore original reduction } -- 2.39.2