Reintroduce eval optimizaion from null search

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 55d815c4b5530359e4d7dbf1269116cd7497138e..f6c2233b1519b8887f19919c789059e603e019d7 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -218,7 +218,7 @@ void Search::think() {
   if (Options["Use Search Log"])
   {
       Log log(Options["Search Log Filename"]);
-      log << "\nSearching: "  << RootPos.to_fen()
+      log << "\nSearching: "  << RootPos.fen()
           << "\ninfinite: "   << Limits.infinite
           << " ponder: "      << Limits.ponder
           << " time: "        << Limits.time[RootColor]
@@ -391,7 +391,8 @@ namespace {
 
             // Sort the PV lines searched so far and update the GUI
             sort<RootMove>(RootMoves.begin(), RootMoves.begin() + PVIdx + 1);
-            sync_cout << uci_pv(pos, depth, alpha, beta) << sync_endl;
+            if (PVIdx + 1 == PVSize || Time::now() - SearchTime > 3000)
+                sync_cout << uci_pv(pos, depth, alpha, beta) << sync_endl;
         }
 
         // Do we need to pick now the sub-optimal best move ?
@@ -573,31 +574,17 @@ namespace {
     // Step 5. Evaluate the position statically and update parent's gain statistics
     if (inCheck)
         ss->staticEval = ss->evalMargin = eval = VALUE_NONE;
-
-    else if (tte)
+    else
     {
-        // Following asserts are valid only in single thread condition because
-        // TT access is always racy and its contents cannot be trusted.
-        assert(tte->static_value() != VALUE_NONE || Threads.size() > 1);
-        assert(ttValue != VALUE_NONE || tte->type() == BOUND_NONE || Threads.size() > 1);
-
-        ss->staticEval = eval = tte->static_value();
-        ss->evalMargin = tte->static_value_margin();
-
-        if (eval == VALUE_NONE || ss->evalMargin == VALUE_NONE) // Due to a race
-            eval = ss->staticEval = evaluate(pos, ss->evalMargin);
+        eval = ss->staticEval = evaluate(pos, ss->evalMargin);
 
         // Can ttValue be used as a better position evaluation?
-        if (ttValue != VALUE_NONE)
+        if (tte && ttValue != VALUE_NONE)
+        {
             if (   ((tte->type() & BOUND_LOWER) && ttValue > eval)
                 || ((tte->type() & BOUND_UPPER) && ttValue < eval))
                 eval = ttValue;
-    }
-    else
-    {
-        eval = ss->staticEval = evaluate(pos, ss->evalMargin);
-        TT.store(posKey, VALUE_NONE, BOUND_NONE, DEPTH_NONE, MOVE_NONE,
-                 ss->staticEval, ss->evalMargin);
+        }
     }
 
     // Update gain for the parent non-capture move given the static position
@@ -793,7 +780,7 @@ split_point_start: // At split points actual search starts from here
       {
           Signals.firstRootMove = (moveCount == 1);
 
-          if (thisThread == Threads.main_thread() && Time::now() - SearchTime > 2000)
+          if (thisThread == Threads.main_thread() && Time::now() - SearchTime > 3000)
               sync_cout << "info depth " << depth / ONE_PLY
                         << " currmove " << move_to_uci(move, pos.is_chess960())
                         << " currmovenumber " << moveCount + PVIdx << sync_endl;
@@ -892,7 +879,7 @@ split_point_start: // At split points actual search starts from here
       }
 
       // Check for legality only before to do the move
-      if (!pos.pl_move_is_legal(move, ci.pinned))
+      if (!RootNode && !SpNode && !pos.pl_move_is_legal(move, ci.pinned))
       {
           moveCount--;
           continue;
@@ -1003,8 +990,10 @@ split_point_start: // At split points actual search starts from here
                   alpha = value; // Update alpha here! Always alpha < beta
                   if (SpNode) sp->alpha = value;
               }
-              else // Fail high
+              else
               {
+                  assert(value >= beta); // Fail high
+
                   if (SpNode) sp->cutoff = true;
                   break;
               }
@@ -1048,8 +1037,7 @@ split_point_start: // At split points actual search starts from here
 
     if (bestValue >= beta) // Failed high
     {
-        TT.store(posKey, value_to_tt(bestValue, ss->ply), BOUND_LOWER, depth,
-                 bestMove, ss->staticEval, ss->evalMargin);
+        TT.store(posKey, value_to_tt(bestValue, ss->ply), BOUND_LOWER, depth, bestMove);
 
         if (!pos.is_capture_or_promotion(bestMove) && !inCheck)
         {
@@ -1074,7 +1062,7 @@ split_point_start: // At split points actual search starts from here
     else // Failed low or PV search
         TT.store(posKey, value_to_tt(bestValue, ss->ply),
                  PvNode && bestMove != MOVE_NONE ? BOUND_EXACT : BOUND_UPPER,
-                 depth, bestMove, ss->staticEval, ss->evalMargin);
+                 depth, bestMove);
 
     assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);
 
@@ -1151,19 +1139,10 @@ split_point_start: // At split points actual search starts from here
     {
         if (fromNull)
         {
+            // Approximated score. Real one is slightly higher due to tempo
             ss->staticEval = bestValue = -(ss-1)->staticEval;
             ss->evalMargin = VALUE_ZERO;
         }
-        else if (tte)
-        {
-            assert(tte->static_value() != VALUE_NONE || Threads.size() > 1);
-
-            ss->staticEval = bestValue = tte->static_value();
-            ss->evalMargin = tte->static_value_margin();
-
-            if (ss->staticEval == VALUE_NONE || ss->evalMargin == VALUE_NONE) // Due to a race
-                ss->staticEval = bestValue = evaluate(pos, ss->evalMargin);
-        }
         else
             ss->staticEval = bestValue = evaluate(pos, ss->evalMargin);
 
@@ -1171,8 +1150,7 @@ split_point_start: // At split points actual search starts from here
         if (bestValue >= beta)
         {
             if (!tte)
-                TT.store(pos.key(), value_to_tt(bestValue, ss->ply), BOUND_LOWER,
-                         DEPTH_NONE, MOVE_NONE, ss->staticEval, ss->evalMargin);
+                TT.store(pos.key(), value_to_tt(bestValue, ss->ply), BOUND_LOWER, DEPTH_NONE, MOVE_NONE);
 
             return bestValue;
         }
@@ -1201,8 +1179,8 @@ split_point_start: // At split points actual search starts from here
       // Futility pruning
       if (   !PvNode
           && !InCheck
-          && !givesCheck
           && !fromNull
+          && !givesCheck
           &&  move != ttMove
           &&  enoughMaterial
           &&  type_of(move) != PROMOTION
@@ -1214,9 +1192,7 @@ split_point_start: // At split points actual search starts from here
 
           if (futilityValue < beta)
           {
-              if (futilityValue > bestValue)
-                  bestValue = futilityValue;
-
+              bestValue = std::max(bestValue, futilityValue);
               continue;
           }
 
@@ -1224,7 +1200,10 @@ split_point_start: // At split points actual search starts from here
           if (   futilityBase < beta
               && depth < DEPTH_ZERO
               && pos.see(move) <= 0)
+          {
+              bestValue = std::max(bestValue, futilityBase);
               continue;
+          }
       }
 
       // Detect non-capture evasions that are candidate to be pruned
@@ -1280,9 +1259,7 @@ split_point_start: // At split points actual search starts from here
               }
               else // Fail high
               {
-                  TT.store(posKey, value_to_tt(value, ss->ply), BOUND_LOWER,
-                           ttDepth, move, ss->staticEval, ss->evalMargin);
-
+                  TT.store(posKey, value_to_tt(value, ss->ply), BOUND_LOWER, ttDepth, move);
                   return value;
               }
           }
@@ -1296,7 +1273,7 @@ split_point_start: // At split points actual search starts from here
 
     TT.store(posKey, value_to_tt(bestValue, ss->ply),
              PvNode && bestValue > oldAlpha ? BOUND_EXACT : BOUND_UPPER,
-             ttDepth, bestMove, ss->staticEval, ss->evalMargin);
+             ttDepth, bestMove);
 
     assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);
 
@@ -1587,20 +1564,12 @@ void RootMove::insert_pv_in_tt(Position& pos) {
   StateInfo state[MAX_PLY_PLUS_2], *st = state;
   TTEntry* tte;
   int ply = 0;
-  Value v, m;
 
   do {
       tte = TT.probe(pos.key());
 
       if (!tte || tte->move() != pv[ply]) // Don't overwrite correct entries
-      {
-          if (pos.in_check())
-              v = m = VALUE_NONE;
-          else
-              v = evaluate(pos, m);
-
-          TT.store(pos.key(), VALUE_NONE, BOUND_NONE, DEPTH_NONE, pv[ply], v, m);
-      }
+          TT.store(pos.key(), VALUE_NONE, BOUND_NONE, DEPTH_NONE, pv[ply]);
 
       assert(pos.move_is_legal(pv[ply]));
       pos.do_move(pv[ply++], *st++);