Only do TT cutoffs when cutnode or fail-low

lynx-chess · Jan 8, 2025 · 8ecc268 · 8ecc268
1 parent 9bda39f
commit 8ecc268
Showing 1 changed file with 2 additions and 5 deletions.
diff --git a/src/Lynx/Search/NegaMax.cs b/src/Lynx/Search/NegaMax.cs
@@ -52,18 +52,15 @@ private int NegaMax(int depth, int ply, int alpha, int beta, bool cutnode, Cance
             // TT cutoffs
             if (!pvNode
                 && ttScore != EvaluationConstants.NoHashEntry
-                && ttDepth >= depth)
+                && ttDepth >= depth
+                && (ttScore <= alpha || cutnode))
             {
                 if (ttElementType == NodeType.Exact
                     || (ttElementType == NodeType.Alpha && ttScore <= alpha)
                     || (ttElementType == NodeType.Beta && ttScore >= beta))
                 {
                     return ttScore;
                 }
-                else if (depth <= 6)
-                {
-                    ++depth;
-                }
             }
 
             // Internal iterative reduction (IIR)