Introduce and use TranspositionTable::refresh()

[stockfish] / src / tt.h

diff --git a/src/tt.h b/src/tt.h
index 9babce8cdc9f10e14500c1f9c4e5cdc6a071d033..ad362de343612296ae0cd435024960b3e57ddc05 100644 (file)
--- a/src/tt.h
+++ b/src/tt.h
@@ -64,6 +64,7 @@ public:
       staticValue = int16_t(statV);
       staticValueMargin  = int16_t(kd);
   }
+  void set_generation(int g) { data = move() | (type() << 21) | (g << 23); }
 
   uint32_t key() const { return key32; }
   Depth depth() const { return Depth(depth16); }
@@ -114,6 +115,7 @@ public:
   TTEntry* retrieve(const Key posKey) const;
   void new_search();
   TTEntry* first_entry(const Key posKey) const;
+  void refresh(const TTEntry* tte) const;
 
 private:
   size_t size;
@@ -133,4 +135,13 @@ inline TTEntry* TranspositionTable::first_entry(const Key posKey) const {
   return entries[uint32_t(posKey) & (size - 1)].data;
 }
 
+
+/// TranspositionTable::refresh updates the 'generation' value of the TTEntry
+/// to avoid aging. Normally called after a TT hit, before to return.
+
+inline void TranspositionTable::refresh(const TTEntry* tte) const {
+
+  const_cast<TTEntry*>(tte)->set_generation(generation);
+}
+
 #endif // !defined(TT_H_INCLUDED)