New try for unstoppable pawn evaluation

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 4bacbef01b6c813a9cd2ec6b1354e3b20b32b909..66a27fa683a91c5345b4f1beace887f5684f6cd0 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -661,7 +661,7 @@ namespace {
              << " time " << current_search_time() << endl;
 
     // Print the best move and the ponder move to the standard output
-    if (pv[0] == MOVE_NONE)
+    if (pv[0] == MOVE_NONE || MultiPV > 1)
     {
         pv[0] = rml.move(0);
         pv[1] = MOVE_NONE;
@@ -1070,7 +1070,6 @@ namespace {
         && !isCheck
         &&  refinedValue < beta - razor_margin(depth)
         &&  ttMove == MOVE_NONE
-        &&  (ss-1)->currentMove != MOVE_NULL
         && !value_is_mate(beta)
         && !pos.has_pawn_on_7th(pos.side_to_move()))
     {
@@ -1287,6 +1286,17 @@ split_point_start: // At split points actual search starts from here
 
               continue;
           }
+
+          // Prune neg. see moves at low depths
+          if (   predictedDepth < 2 * ONE_PLY
+              && bestValue > value_mated_in(PLY_MAX)
+              && pos.see_sign(move) < 0)
+          {
+              if (SpNode)
+                  lock_grab(&(sp->lock));
+
+              continue;
+          }
       }
 
       // Step 13. Make the move