Remove cutNode condition

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 55be43b30f5594a09d7851469ef4238eff0d81a6..b3ca8c9afe531582cd41811f8aeaf190bbb33c74 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -780,7 +780,7 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo
              >= beta
         && eval >= beta && eval < 29462  // smaller than TB wins
         && (!ttMove || ttCapture))
-        return eval;
+        return (eval + beta) / 2;
 
     // Step 9. Null move search with verification search (~35 Elo)
     if (!PvNode && (ss - 1)->currentMove != MOVE_NULL && (ss - 1)->statScore < 17257 && eval >= beta
@@ -1165,13 +1165,13 @@ moves_loop:  // When in check, search starts here
                       + (*contHist[3])[movedPiece][to_sq(move)] - 3848;
 
         // Decrease/increase reduction for moves with a good/bad history (~25 Elo)
-        r -= ss->statScore / (10216 + 3855 * (depth > 5 && depth < 23));
+        r -= ss->statScore / 14200;
 
         // Step 17. Late moves reduction / extension (LMR, ~117 Elo)
         // We use various heuristics for the sons of a node after the first son has
         // been searched. In general, we would like to reduce them, but there are many
         // cases where we extend a son if it has good chances to be "interesting".
-        if (depth >= 2 && moveCount > 1 + (PvNode && ss->ply <= 1)
+        if (depth >= 2 && moveCount > 1 + rootNode
             && (!ss->ttPv || !capture || (cutNode && (ss - 1)->moveCount > 1)))
         {
             // In general we want to cap the LMR depth search at newDepth, but when
@@ -1188,9 +1188,8 @@ moves_loop:  // When in check, search starts here
             {
                 // Adjust full-depth search based on LMR results - if the result
                 // was good enough search deeper, if it was bad enough search shallower.
-                const bool doDeeperSearch =
-                  value > (bestValue + 51 + 10 * (newDepth - d));             // (~1 Elo)
-                const bool doShallowerSearch = value < bestValue + newDepth;  // (~2 Elo)
+                const bool doDeeperSearch    = value > (bestValue + 50 + 2 * newDepth);  // (~1 Elo)
+                const bool doShallowerSearch = value < bestValue + newDepth;             // (~2 Elo)
 
                 newDepth += doDeeperSearch - doShallowerSearch;
 
@@ -1208,8 +1207,8 @@ moves_loop:  // When in check, search starts here
         // Step 18. Full-depth search when LMR is skipped
         else if (!PvNode || moveCount > 1)
         {
-            // Increase reduction for cut nodes without ttMove (~1 Elo)
-            if (!ttMove && cutNode)
+            // Increase reduction if ttMove is not present (~1 Elo)
+            if (!ttMove)
                 r += 2;
 
             // Note that if expected reduction is high, we reduce search depth by 1 here
@@ -1488,7 +1487,7 @@ Value qsearch(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth) {
     // will be generated.
     Square     prevSq = is_ok((ss - 1)->currentMove) ? to_sq((ss - 1)->currentMove) : SQ_NONE;
     MovePicker mp(pos, ttMove, depth, &thisThread->mainHistory, &thisThread->captureHistory,
-                  contHist, &thisThread->pawnHistory, prevSq);
+                  contHist, &thisThread->pawnHistory);
 
     int quietCheckEvasions = 0;
 
@@ -1688,7 +1687,7 @@ void update_all_stats(const Position& pos,
     PieceType              captured;
 
     int quietMoveBonus = stat_bonus(depth + 1);
-    int quietMoveMalus = stat_malus(depth + 1);
+    int quietMoveMalus = stat_malus(depth);
 
     if (!pos.capture_stage(bestMove))
     {
@@ -1899,9 +1898,9 @@ string UCI::pv(const Position& pos, Depth depth) {
 }
 
 
-// Called in case we have no ponder move
-// before exiting the search, for instance, in case we stop the search during a
-// fail high at root. We try hard to have a ponder move to return to the GUI,
+// Called in case we have no ponder move before exiting the search,
+// for instance, in case we stop the search during a fail high at root.
+// We try hard to have a ponder move to return to the GUI,
 // otherwise in case of 'ponder on' we have nothing to think about.
 bool RootMove::extract_ponder_from_tt(Position& pos) {