Extend maximum hash size to 8 GB

Signed-off-by: Marco Costalba <mcostalba@gmail.com>

src/tt.cpp

@@ -55,9 +55,9 @@ TranspositionTable::~TranspositionTable() {
 
 void TranspositionTable::set_size(unsigned mbSize) {
 
-  assert(mbSize >= 4 && mbSize <= 2048);
+  assert(mbSize >= 4 && mbSize <= 8192);
 
-  unsigned newSize = 1024;
+  size_t newSize = 1024;
 
   // We store a cluster of ClusterSize number of TTEntry for each position
   // and newSize is the maximum number of storable positions.

src/tt.h

@@ -114,7 +114,7 @@ private:
   unsigned writes; // heavy SMP read/write access here
   unsigned char pad_after[64];
 
-  unsigned size;
+  size_t size;
   TTCluster* entries;
   uint8_t generation;
 };

src/ucioption.cpp

@@ -123,7 +123,7 @@ namespace {
     o["Minimum Split Depth"] = Option(4, 4, 7);
     o["Maximum Number of Threads per Split Point"] = Option(5, 4, 8);
     o["Threads"] = Option(1, 1, THREAD_MAX);
-    o["Hash"] = Option(32, 4, 2048);
+    o["Hash"] = Option(32, 4, 8192);
     o["Clear Hash"] = Option(false, BUTTON);
     o["New Game"] = Option(false, BUTTON);
     o["Ponder"] = Option(true);