X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=1214cbdcbd2b02f32d7b132ef02cd5ce4f400264;hp=c256cfc01a9615bd6c5d11f6c6b21d30f2991500;hb=0fc9a01933ce33fda3732c1d5bbde5a8908d0019;hpb=c5ec94d0f1b128fc2c691c7231663a345409d5cc

diff --git a/src/search.cpp b/src/search.cpp
index c256cfc0..1214cbdc 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -857,16 +857,14 @@ split_point_start: // At split points actual search starts from here
       newDepth = depth - ONE_PLY + ext;
 
       // Step 13. Futility pruning (is omitted in PV nodes)
-      if (   !PvNode
-          && !captureOrPromotion
+      if (   !captureOrPromotion
           && !inCheck
           && !dangerous
-          &&  move != ttMove
-          && (bestValue > VALUE_MATED_IN_MAX_PLY || (   bestValue == -VALUE_INFINITE
-                                                     && alpha > VALUE_MATED_IN_MAX_PLY)))
+          &&  move != ttMove)
       {
           // Move count based pruning
-          if (   depth < 16 * ONE_PLY
+          if (   !PvNode
+              && depth < 16 * ONE_PLY
               && moveCount >= FutilityMoveCounts[depth]
               && (!threatMove || !refutes(pos, move, threatMove)))
           {
@@ -883,7 +881,7 @@ split_point_start: // At split points actual search starts from here
           futilityValue =  ss->staticEval + ss->evalMargin + futility_margin(predictedDepth, moveCount)
                          + Gain[pos.piece_moved(move)][to_sq(move)];
 
-          if (futilityValue < beta)
+          if (!PvNode && futilityValue < beta)
           {
               if (SpNode)
                   sp->mutex.lock();
@@ -929,7 +927,8 @@ split_point_start: // At split points actual search starts from here
       {
           ss->reduction = reduction<PvNode>(depth, moveCount);
           Depth d = std::max(newDepth - ss->reduction, ONE_PLY);
-          alpha = SpNode ? sp->alpha : alpha;
+          if (SpNode)
+              alpha = sp->alpha;
 
           value = -search<NonPV>(pos, ss+1, -(alpha+1), -alpha, d);
 
@@ -942,7 +941,9 @@ split_point_start: // At split points actual search starts from here
       // Step 16. Full depth search, when LMR is skipped or fails high
       if (doFullDepthSearch)
       {
-          alpha = SpNode ? sp->alpha : alpha;
+          if (SpNode)
+              alpha = sp->alpha;
+
           value = newDepth < ONE_PLY ?
                           givesCheck ? -qsearch<NonPV,  true>(pos, ss+1, -(alpha+1), -alpha, DEPTH_ZERO)
                                      : -qsearch<NonPV, false>(pos, ss+1, -(alpha+1), -alpha, DEPTH_ZERO)