Increase TT size limit to 8 GB

[stockfish] / src / movepick.cpp

diff --git a/src/movepick.cpp b/src/movepick.cpp
index 16eb16348c1791f2761f36c8f2d96d1ce039c35d..638f81757d2af94d72c9b0c6739ab1d191d2c6f5 100644 (file)
--- a/src/movepick.cpp
+++ b/src/movepick.cpp
@@ -94,8 +94,16 @@ MovePicker::MovePicker(const Position& p, Move ttm, Depth d,
   else if (d == Depth(0))
       phasePtr = QsearchWithChecksPhaseTable;
   else
+  {
       phasePtr = QsearchWithoutChecksPhaseTable;
 
+      // Skip TT move if is not a capture or a promotion, this avoids
+      // qsearch tree explosion due to a possible perpetual check or
+      // similar rare cases when TT table is full.
+      if (ttm != MOVE_NONE && !pos.move_is_capture_or_promotion(ttm))
+          searchTT = ttMoves[0].move = MOVE_NONE;
+  }
+
   phasePtr += !searchTT - 1;
   go_next_phase();
 }