X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Ftt.h;h=a983805b19afdc5ae207097c4a2539862d0a4740;hp=32b4036e39dea085974410867b7212facfc6c625;hb=307a5a4f63169fd215860dc478dcf2a9db2c46e8;hpb=8d16111ffde1689d48d47ec379ba91613213183c

diff --git a/src/tt.h b/src/tt.h
index 32b4036e..a983805b 100644
--- a/src/tt.h
+++ b/src/tt.h
@@ -43,14 +43,22 @@ struct TTEntry {
 
   void save(Key k, Value v, Bound b, Depth d, Move m, Value ev, uint8_t g) {
 
-    if (m || (k >> 48) != key16) // Preserve any existing move for the same position
+    // Preserve any existing move for the same position
+    if (m || (k >> 48) != key16)
         move16 = (uint16_t)m;
 
-    key16     = (uint16_t)(k >> 48);
-    value16   = (int16_t)v;
-    eval16    = (int16_t)ev;
-    genBound8 = (uint8_t)(g | b);
-    depth8    = (int8_t)d;
+    // Don't overwrite more valuable entries
+    if (  (k >> 48) != key16
+        || d > depth8 - 2
+     /* || g != (genBound8 & 0xFC) // Matching non-zero keys are already refreshed by probe() */
+        || b == BOUND_EXACT)
+    {
+        key16     = (uint16_t)(k >> 48);
+        value16   = (int16_t)v;
+        eval16    = (int16_t)ev;
+        genBound8 = (uint8_t)(g | b);
+        depth8    = (int8_t)d;
+    }
   }
 
 private: