Revert "Revert "Revert "Shuffle detection #2064"""

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 53f61a97067ad79cf00afa5bec71b3dad514bab4..98419b20fc75b9ee7bde88ce952da472719fff34 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -662,15 +662,6 @@ namespace {
             : ttHit    ? tte->move() : MOVE_NONE;
     ttPv = PvNode || (ttHit && tte->is_pv());
 
             : ttHit    ? tte->move() : MOVE_NONE;
     ttPv = PvNode || (ttHit && tte->is_pv());
 

-    // if position has been searched at higher depths and we are shuffling, return value_draw
-    if (pos.rule50_count() > 36
-        && ss->ply > 36
-        && depth < 3 * ONE_PLY
-        && ttHit
-        && tte->depth() > depth
-        && pos.count<PAWN>() > 0)
-        return VALUE_DRAW;
-

     // At non-PV nodes we check for an early TT cutoff
     if (  !PvNode
         && ttHit
     // At non-PV nodes we check for an early TT cutoff
     if (  !PvNode
         && ttHit


@@ -998,10 +989,6 @@ moves_loop: // When in check, search starts from here
                && (pos.is_discovery_check_on_king(~us, move) || pos.see_ge(move)))
           extension = ONE_PLY;
 
                && (pos.is_discovery_check_on_king(~us, move) || pos.see_ge(move)))
           extension = ONE_PLY;
 

-      // Shuffle extension
-      else if(pos.rule50_count() > 14 && ss->ply > 14 && depth < 3 * ONE_PLY && PvNode)
-          extension = ONE_PLY;
-

       // Castling extension
       else if (type_of(move) == CASTLING)
           extension = ONE_PLY;
       // Castling extension
       else if (type_of(move) == CASTLING)
           extension = ONE_PLY;