Do move legality check before pruning.

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index d1dc4489133387df5d0545f5277b6b0ebd9bd3ae..2f83f4f45b017fa7a9bfde67c155c28dbcc431a4 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -986,6 +986,10 @@ moves_loop: // When in check, search starts from here
                                   thisThread->rootMoves.begin() + thisThread->pvLast, move))
           continue;
 
+      // Check for legality
+      if (!rootNode && !pos.legal(move))
+          continue;
+
       ss->moveCount = ++moveCount;
 
       if (rootNode && thisThread == Threads.main() && Time.elapsed() > 3000)
@@ -1137,13 +1141,6 @@ moves_loop: // When in check, search starts from here
       // Speculative prefetch as early as possible
       prefetch(TT.first_entry(pos.key_after(move)));
 
-      // Check for legality just before making the move
-      if (!rootNode && !pos.legal(move))
-      {
-          ss->moveCount = --moveCount;
-          continue;
-      }
-
       // Update the current move (this must be done after singular extension search)
       ss->currentMove = move;
       ss->continuationHistory = &thisThread->continuationHistory[ss->inCheck]