X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=ef83f4598da967c20b49d304df451d92db02c583;hp=85d702c4d4c410e0eb4e5eb045977c6d891e5114;hb=f133f61e3fb5a777857f51d995e9bb3d263cf404;hpb=83a574ff271ec5924976b48cf65ac62278f87558

diff --git a/src/search.cpp b/src/search.cpp
index 85d702c4..ef83f459 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -42,7 +42,6 @@ namespace Search {
   LimitsType Limits;
   std::vector<RootMove> RootMoves;
   Position RootPos;
-  Color RootColor;
   Time::point SearchTime;
   StateStackPtr SetupStates;
 }
@@ -53,9 +52,6 @@ using namespace Search;
 
 namespace {
 
-  // Set to true to force running with one thread. Used for debugging
-  const bool FakeSplit = false;
-
   // Different node types, used as template parameter
   enum NodeType { Root, PV, NonPV };
 
@@ -180,12 +176,11 @@ uint64_t Search::perft(Position& pos, Depth depth) {
 
 void Search::think() {
 
-  RootColor = RootPos.side_to_move();
-  TimeMgr.init(Limits, RootPos.game_ply(), RootColor);
+  TimeMgr.init(Limits, RootPos.game_ply(), RootPos.side_to_move());
 
   int cf = Options["Contempt Factor"] * PawnValueEg / 100; // From centipawns
-  DrawValue[ RootColor] = VALUE_DRAW - Value(cf);
-  DrawValue[~RootColor] = VALUE_DRAW + Value(cf);
+  DrawValue[ RootPos.side_to_move()] = VALUE_DRAW - Value(cf);
+  DrawValue[~RootPos.side_to_move()] = VALUE_DRAW + Value(cf);
 
   if (RootMoves.empty())
   {
@@ -203,8 +198,8 @@ void Search::think() {
       log << "\nSearching: "  << RootPos.fen()
           << "\ninfinite: "   << Limits.infinite
           << " ponder: "      << Limits.ponder
-          << " time: "        << Limits.time[RootColor]
-          << " increment: "   << Limits.inc[RootColor]
+          << " time: "        << Limits.time[RootPos.side_to_move()]
+          << " increment: "   << Limits.inc[RootPos.side_to_move()]
           << " moves to go: " << Limits.movestogo
           << "\n" << std::endl;
   }
@@ -272,7 +267,6 @@ namespace {
     Value bestValue, alpha, beta, delta;
 
     std::memset(ss-2, 0, 5 * sizeof(Stack));
-    (ss-1)->currentMove = MOVE_NULL; // Hack to skip update gains
 
     depth = 0;
     BestMoveChanges = 0;
@@ -401,7 +395,7 @@ namespace {
         if (Limits.use_time_management() && !Signals.stop && !Signals.stopOnPonderhit)
         {
             // Take some extra time if the best move has changed
-            if (depth > 4 && depth < 50 &&  MultiPV == 1)
+            if (depth > 4 && MultiPV == 1)
                 TimeMgr.pv_instability(BestMoveChanges);
 
             // Stop the search if only one legal move is available or all
@@ -547,7 +541,9 @@ namespace {
     }
     else
     {
-        eval = ss->staticEval = evaluate(pos);
+        eval = ss->staticEval =
+        (ss-1)->currentMove != MOVE_NULL ? evaluate(pos) : -(ss-1)->staticEval + 2 * Eval::Tempo;
+
         TT.store(posKey, VALUE_NONE, BOUND_NONE, DEPTH_NONE, MOVE_NONE, ss->staticEval);
     }
 
@@ -555,6 +551,7 @@ namespace {
         &&  ss->staticEval != VALUE_NONE
         && (ss-1)->staticEval != VALUE_NONE
         && (move = (ss-1)->currentMove) != MOVE_NULL
+        &&  move != MOVE_NONE
         &&  type_of(move) == NORMAL)
     {
         Square to = to_sq(move);
@@ -566,7 +563,6 @@ namespace {
         &&  depth < 4 * ONE_PLY
         &&  eval + razor_margin(depth) <= alpha
         &&  ttMove == MOVE_NONE
-        &&  abs(beta) < VALUE_MATE_IN_MAX_PLY
         && !pos.pawn_on_7th(pos.side_to_move()))
     {
         if (   depth <= ONE_PLY
@@ -594,7 +590,6 @@ namespace {
         && !ss->skipNullMove
         &&  depth >= 2 * ONE_PLY
         &&  eval >= beta
-        &&  abs(beta) < VALUE_MATE_IN_MAX_PLY
         &&  pos.non_pawn_material(pos.side_to_move()))
     {
         ss->currentMove = MOVE_NULL;
@@ -604,7 +599,8 @@ namespace {
         // Null move dynamic reduction based on depth and value
         Depth R =  3 * ONE_PLY
                  + depth / 4
-                 + int(eval - beta) / PawnValueMg * ONE_PLY;
+                 + (abs(beta) < VALUE_KNOWN_WIN ? int(eval - beta) / PawnValueMg * ONE_PLY
+                                                : DEPTH_ZERO);
 
         pos.do_null_move(st);
         (ss+1)->skipNullMove = true;
@@ -619,7 +615,7 @@ namespace {
             if (nullValue >= VALUE_MATE_IN_MAX_PLY)
                 nullValue = beta;
 
-            if (depth < 12 * ONE_PLY)
+            if (depth < 12 * ONE_PLY && abs(beta) < VALUE_KNOWN_WIN)
                 return nullValue;
 
             // Do verification search at high depths
@@ -699,7 +695,10 @@ moves_loop: // When in check and at SpNode search starts from here
     singularExtensionNode =   !RootNode
                            && !SpNode
                            &&  depth >= 8 * ONE_PLY
+                           &&  abs(beta) < VALUE_KNOWN_WIN
                            &&  ttMove != MOVE_NONE
+                       /*  &&  ttValue != VALUE_NONE Already implicit in the next condition */
+                           &&  abs(ttValue) < VALUE_KNOWN_WIN
                            && !excludedMove // Recursive singular search is not allowed
                            && (tte->bound() & BOUND_LOWER)
                            &&  tte->depth() >= depth - 3 * ONE_PLY;
@@ -764,11 +763,8 @@ moves_loop: // When in check and at SpNode search starts from here
       if (    singularExtensionNode
           &&  move == ttMove
           && !ext
-          &&  pos.legal(move, ci.pinned)
-          &&  abs(ttValue) < VALUE_KNOWN_WIN)
+          &&  pos.legal(move, ci.pinned))
       {
-          assert(ttValue != VALUE_NONE);
-
           Value rBeta = ttValue - int(depth);
           ss->excludedMove = move;
           ss->skipNullMove = true;
@@ -870,8 +866,9 @@ moves_loop: // When in check and at SpNode search starts from here
 
           // Decrease reduction for moves that escape a capture
           if (   ss->reduction
+              && type_of(move) == NORMAL
               && type_of(pos.piece_on(to_sq(move))) != PAWN
-              && pos.see_sign(make_move(to_sq(move), from_sq(move))) < 0)
+              && pos.see(make_move(to_sq(move), from_sq(move))) < 0)
               ss->reduction = std::max(DEPTH_ZERO, ss->reduction - ONE_PLY);
 
           Depth d = std::max(newDepth - ss->reduction, ONE_PLY);
@@ -987,8 +984,8 @@ moves_loop: // When in check and at SpNode search starts from here
       {
           assert(bestValue > -VALUE_INFINITE && bestValue < beta);
 
-          thisThread->split<FakeSplit>(pos, ss, alpha, beta, &bestValue, &bestMove,
-                                       depth, moveCount, &mp, NT, cutNode);
+          thisThread->split(pos, ss, alpha, beta, &bestValue, &bestMove,
+                            depth, moveCount, &mp, NT, cutNode);
 
           if (Signals.stop || thisThread->cutoff_occurred())
               return VALUE_ZERO;
@@ -1109,7 +1106,8 @@ moves_loop: // When in check and at SpNode search starts from here
                     bestValue = ttValue;
         }
         else
-            ss->staticEval = bestValue = evaluate(pos);
+            ss->staticEval = bestValue =
+            (ss-1)->currentMove != MOVE_NULL ? evaluate(pos) : -(ss-1)->staticEval + 2 * Eval::Tempo;
 
         // Stand pat. Return immediately if static value is at least beta
         if (bestValue >= beta)
@@ -1552,7 +1550,7 @@ void Thread::idle_loop() {
           if (Threads.size() > 2)
               for (size_t i = 0; i < Threads.size(); ++i)
               {
-                  int size = Threads[i]->splitPointsSize; // Local copy
+                  const int size = Threads[i]->splitPointsSize; // Local copy
                   sp = size ? &Threads[i]->splitPoints[size - 1] : NULL;
 
                   if (   sp