Retire value_is_mate()

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 9a62fb793290e5cd49b241653645f532ed8f778c..1660fcb151e573b5fe5f9ea6f0360e2be4c3e9c4 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -293,14 +293,12 @@ namespace {
 
   bool check_is_dangerous(Position &pos, Move move, Value futilityBase, Value beta, Value *bValue);
   bool connected_moves(const Position& pos, Move m1, Move m2);
-  bool value_is_mate(Value value);
   Value value_to_tt(Value v, int ply);
   Value value_from_tt(Value v, int ply);
   bool ok_to_use_TT(const TTEntry* tte, Depth depth, Value beta, int ply);
   bool connected_threat(const Position& pos, Move m, Move threat);
   Value refine_eval(const TTEntry* tte, Value defaultEval, int ply);
   void update_history(const Position& pos, Move move, Depth depth, Move movesSearched[], int moveCount);
-  void update_killers(Move m, Move killers[]);
   void update_gains(const Position& pos, Move move, Value before, Value after);
 
   int current_search_time();
@@ -922,7 +920,7 @@ namespace {
         && !isCheck
         &&  refinedValue < beta - razor_margin(depth)
         &&  ttMove == MOVE_NONE
-        && !value_is_mate(beta)
+        &&  abs(beta) < value_mate_in(PLY_MAX)
         && !pos.has_pawn_on_7th(pos.side_to_move()))
     {
         Value rbeta = beta - razor_margin(depth);
@@ -941,7 +939,7 @@ namespace {
         &&  depth < RazorDepth
         && !isCheck
         &&  refinedValue >= beta + futility_margin(depth, 0)
-        && !value_is_mate(beta)
+        &&  abs(beta) < value_mate_in(PLY_MAX)
         &&  pos.non_pawn_material(pos.side_to_move()))
         return refinedValue - futility_margin(depth, 0);
 
@@ -951,7 +949,7 @@ namespace {
         &&  depth > ONE_PLY
         && !isCheck
         &&  refinedValue >= beta
-        && !value_is_mate(beta)
+        &&  abs(beta) < value_mate_in(PLY_MAX)
         &&  pos.non_pawn_material(pos.side_to_move()))
     {
         ss->currentMove = MOVE_NULL;
@@ -1347,8 +1345,12 @@ split_point_start: // At split points actual search starts from here
         if (    bestValue >= beta
             && !pos.move_is_capture_or_promotion(move))
         {
+            if (move != ss->killers[0])
+            {
+                ss->killers[1] = ss->killers[0];
+                ss->killers[0] = move;
+            }
             update_history(pos, move, depth, movesSearched, playedMoveCount);
-            update_killers(move, ss->killers);
         }
     }
 
@@ -1666,18 +1668,6 @@ split_point_start: // At split points actual search starts from here
   }
 
 
-  // value_is_mate() checks if the given value is a mate one eventually
-  // compensated for the ply.
-
-  bool value_is_mate(Value value) {
-
-    assert(abs(value) <= VALUE_INFINITE);
-
-    return   value <= value_mated_in(PLY_MAX)
-          || value >= value_mate_in(PLY_MAX);
-  }
-
-
   // value_to_tt() adjusts a mate score from "plies to mate from the root" to
   // "plies to mate from the current ply".  Non-mate scores are unchanged.
   // The function is called before storing a value to the transposition table.
@@ -1867,19 +1857,6 @@ split_point_start: // At split points actual search starts from here
   }
 
 
-  // update_killers() add a good move that produced a beta-cutoff
-  // among the killer moves of that ply.
-
-  void update_killers(Move m, Move killers[]) {
-
-    if (m != killers[0])
-    {
-        killers[1] = killers[0];
-        killers[0] = m;
-    }
-  }
-
-
   // update_gains() updates the gains table of a non-capture move given
   // the static position evaluation before and after the move.
 
@@ -1893,6 +1870,7 @@ split_point_start: // At split points actual search starts from here
         H.update_gain(pos.piece_on(move_to(m)), move_to(m), -(before + after));
   }
 
+
   // current_search_time() returns the number of milliseconds which have passed
   // since the beginning of the current search.
 
@@ -1916,7 +1894,7 @@ split_point_start: // At split points actual search starts from here
     if (abs(v) < VALUE_MATE - PLY_MAX * ONE_PLY)
       s << "cp " << int(v) * 100 / int(PawnValueMidgame); // Scale to centipawns
     else
-      s << "mate " << (v > 0 ? (VALUE_MATE - v + 1) / 2 : -(VALUE_MATE + v) / 2);
+      s << "mate " << (v > 0 ? VALUE_MATE - v + 1 : -VALUE_MATE - v) / 2;
 
     return s.str();
   }
@@ -1953,10 +1931,7 @@ split_point_start: // At split points actual search starts from here
         // We are line oriented, don't read single chars
         std::string command;
 
-        if (!std::getline(std::cin, command))
-            command = "quit";
-
-        if (command == "quit")
+        if (!std::getline(std::cin, command) || command == "quit")
         {
             // Quit the program as soon as possible
             Pondering = false;
@@ -2034,20 +2009,12 @@ split_point_start: // At split points actual search starts from here
 
     std::string command;
 
-    while (true)
-    {
-        // Wait for a command from stdin
-        if (!std::getline(std::cin, command))
-            command = "quit";
+    // Wait for a command from stdin
+    while (   std::getline(std::cin, command)
+           && command != "ponderhit" && command != "stop" && command != "quit") {};
 
-        if (command == "quit")
-        {
-            QuitRequest = true;
-            break;
-        }
-        else if (command == "ponderhit" || command == "stop")
-            break;
-    }
+    if (command != "ponderhit" && command != "stop")
+        QuitRequest = true; // Must be "quit" or getline() returned false
   }