Futility tweak

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index a81c85273aa4e6325e103dcd1d7ec1afc2636054..64e9028b10bd82fd1c7bc2d77e52bb960f17048f 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -65,7 +65,7 @@ namespace {
 
   // Razoring and futility margin based on depth
   const int razor_margin[4] = { 483, 570, 603, 554 };
 
   // Razoring and futility margin based on depth
   const int razor_margin[4] = { 483, 570, 603, 554 };

-  Value futility_margin(Depth d) { return Value(200 * d); }
+  Value futility_margin(Depth d) { return Value(150 * d); }

 
   // Futility and reductions lookup tables, initialized at startup
   int FutilityMoveCounts[2][16];  // [improving][depth]
 
   // Futility and reductions lookup tables, initialized at startup
   int FutilityMoveCounts[2][16];  // [improving][depth]


@@ -926,7 +926,7 @@ moves_loop: // When in check search starts from here
 
           // Futility pruning: parent node
           if (   predictedDepth < 7 * ONE_PLY
 
           // Futility pruning: parent node
           if (   predictedDepth < 7 * ONE_PLY

-              && ss->staticEval + futility_margin(predictedDepth) + 256 <= alpha)
+              && ss->staticEval + 256 + 200 * predictedDepth / ONE_PLY <= alpha)

               continue;
 
           // Prune moves with negative SEE at low depths and below a decreasing
               continue;
 
           // Prune moves with negative SEE at low depths and below a decreasing