Reformat PassedPawnsBonus

[stockfish] / src / tt.cpp

diff --git a/src/tt.cpp b/src/tt.cpp
index cc3bea2023d7d51d3f0b3149a991420bde05572a..a9f8f037ab92925f80a62c7a26d5dfc2be7849d7 100644 (file)
--- a/src/tt.cpp
+++ b/src/tt.cpp
@@ -28,12 +28,10 @@ TranspositionTable TT; // Our global transposition table
 
 /// TranspositionTable::resize() sets the size of the transposition table,
 /// measured in megabytes. Transposition table consists of a power of 2 number
-/// of clusters and each cluster consists of TTClusterSize number of TTEntry.
+/// of clusters and each cluster consists of ClusterSize number of TTEntry.
 
 void TranspositionTable::resize(size_t mbSize) {
 
-  assert(sizeof(Cluster) == CacheLineSize / 2);
-
   size_t newClusterCount = size_t(1) << msb((mbSize * 1024 * 1024) / sizeof(Cluster));
 
   if (newClusterCount == clusterCount)
@@ -68,16 +66,16 @@ void TranspositionTable::clear() {
 /// TranspositionTable::probe() looks up the current position in the transposition
 /// table. It returns true and a pointer to the TTEntry if the position is found.
 /// Otherwise, it returns false and a pointer to an empty or least valuable TTEntry
-/// to be replaced later. A TTEntry t1 is considered to be more valuable than a
-/// TTEntry t2 if t1 is from the current search and t2 is from a previous search,
-/// or if the depth of t1 is bigger than the depth of t2.
+/// to be replaced later. The replace value of an entry is calculated as its depth
+/// minus 8 times its relative age. TTEntry t1 is considered more valuable than
+/// TTEntry t2 if its replace value is greater than that of t2.
 
 TTEntry* TranspositionTable::probe(const Key key, bool& found) const {
 
   TTEntry* const tte = first_entry(key);
   const uint16_t key16 = key >> 48;  // Use the high 16 bits as key inside the cluster
 
-  for (int i = 0; i < TTClusterSize; ++i)
+  for (int i = 0; i < ClusterSize; ++i)
       if (!tte[i].key16 || tte[i].key16 == key16)
       {
           if (tte[i].key16)
@@ -88,11 +86,27 @@ TTEntry* TranspositionTable::probe(const Key key, bool& found) const {
 
   // Find an entry to be replaced according to the replacement strategy
   TTEntry* replace = tte;
-  for (int i = 1; i < TTClusterSize; ++i)
-      if (  ((  tte[i].genBound8 & 0xFC) == generation8 || tte[i].bound() == BOUND_EXACT)
-          - ((replace->genBound8 & 0xFC) == generation8)
-          - (tte[i].depth8 < replace->depth8) < 0)
+  for (int i = 1; i < ClusterSize; ++i)
+      if (  replace->depth8 - ((259 + generation8 - replace->genBound8) & 0xFC) * 2 * ONE_PLY
+          >   tte[i].depth8 - ((259 + generation8 -   tte[i].genBound8) & 0xFC) * 2 * ONE_PLY)
           replace = &tte[i];
 
   return found = false, replace;
 }
+
+
+/// Returns an approximation of the hashtable occupation during a search. The
+/// hash is x permill full, as per UCI protocol.
+
+int TranspositionTable::hashfull() const
+{
+  int cnt = 0;
+  for (int i = 0; i < 1000 / ClusterSize; i++)
+  {
+      const TTEntry* tte = &table[i].entry[0];
+      for (int j = 0; j < ClusterSize; j++)
+          if ((tte[j].genBound8 & 0xFC) == generation8)
+              cnt++;
+  }
+  return cnt;
+}