diff --git a/src/search.cpp b/src/search.cpp index 3e6e38bd..6d900f7b 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -595,7 +595,7 @@ namespace { // Step 6. Razoring (skipped when in check) if ( !PvNode && depth < 4 * ONE_PLY - && eval + razor_margin(depth) < beta + && eval + razor_margin(depth) <= alpha && ttMove == MOVE_NONE && abs(beta) < VALUE_MATE_IN_MAX_PLY && !pos.pawn_on_7th(pos.side_to_move())) @@ -640,24 +640,8 @@ namespace { (ss+1)->skipNullMove = false; pos.undo_null_move(); - if (nullValue >= beta) - { - // Do not return unproven mate scores - if (nullValue >= VALUE_MATE_IN_MAX_PLY) - nullValue = beta; - - if (depth < 12 * ONE_PLY) - return nullValue; - - // Do verification search at high depths - ss->skipNullMove = true; - Value v = depth-R < ONE_PLY ? qsearch(pos, ss, beta-1, beta, DEPTH_ZERO) - : search(pos, ss, beta-1, beta, depth-R, false); - ss->skipNullMove = false; - - if (v >= beta) - return nullValue; - } + if (nullValue >= beta) // Do not return unproven mate scores + return nullValue >= VALUE_MATE_IN_MAX_PLY ? beta : nullValue; } // Step 9. ProbCut (skipped when in check)