From abae3c5678897be39fd7a082543937f846dcfbd5 Mon Sep 17 00:00:00 2001 From: Joona Kiiski Date: Sun, 11 Apr 2010 20:27:34 +0300 Subject: [PATCH] Prevent the use of nullmove TT value only at verification search Signed-off-by: Marco Costalba --- src/search.cpp | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/search.cpp b/src/search.cpp index aaff2f54..043c433a 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -1306,7 +1306,7 @@ namespace { tte = TT.retrieve(posKey); ttMove = (tte ? tte->move() : MOVE_NONE); - if (tte && ok_to_use_TT(tte, depth, beta, ply, nullStatus == ALLOW_NULLMOVE)) + if (tte && ok_to_use_TT(tte, depth, beta, ply, nullStatus != VERIFY_NULLMOVE)) { ss[ply].currentMove = ttMove; // Can be MOVE_NONE return value_from_tt(tte->value(), ply); @@ -1389,7 +1389,7 @@ namespace { // Do zugzwang verification search for high depths, don't store in TT // if search was stopped. if ( ( depth < 6 * OnePly - || search(pos, ss, beta, depth-5*OnePly, ply, FORBID_NULLMOVE, threadID) >= beta) + || search(pos, ss, beta, depth-5*OnePly, ply, VERIFY_NULLMOVE, threadID) >= beta) && !AbortSearch && !TM.thread_should_stop(threadID)) { -- 2.39.2