Retire singleEvasion

This let us get rid of number_of_evasions()

After 5487 games
Mod- Orig: 851 - 852 - 3784 +0 ELO  (+- 3.7)

Signed-off-by: Marco Costalba <mcostalba@gmail.com>

diff --git a/src/movepick.h b/src/movepick.h
index d97bb62909c71ceb38ed0affba20216994b99bd2..ad76085bd86bbf08fae48ea02044a92a16e85dfb 100644 (file)
--- a/src/movepick.h
+++ b/src/movepick.h
@@ -42,7 +42,6 @@ public:
   MovePicker(const Position& p, Move ttm, Depth d, const History& h, SearchStack* ss, Value beta);
   MovePicker(const Position& p, Move ttm, Depth d, const History& h);
   Move get_next_move();
   MovePicker(const Position& p, Move ttm, Depth d, const History& h, SearchStack* ss, Value beta);
   MovePicker(const Position& p, Move ttm, Depth d, const History& h);
   Move get_next_move();

-  int number_of_evasions() const;

 
 private:
   void score_captures();
 
 private:
   void score_captures();


@@ -60,15 +59,4 @@ private:
   MoveStack moves[MOVES_MAX];
 };
 
   MoveStack moves[MOVES_MAX];
 };
 

-
-/// MovePicker::number_of_evasions() simply returns the number of moves in
-/// evasions phase. It is intended to be used in positions where the side to
-/// move is in check, for detecting checkmates or situations where there is
-/// only a single reply to check.
-/// WARNING: It works as long as PH_EVASIONS is the _only_ phase for evasions.
-
-inline int MovePicker::number_of_evasions() const {
-  return int(lastMove - moves);
-}
-

 #endif // !defined(MOVEPICK_H_INCLUDED)
 #endif // !defined(MOVEPICK_H_INCLUDED)

diff --git a/src/search.cpp b/src/search.cpp
index 3f482e77146490cad1fc57e4ca06fd5efec64726..eb19b51d9c994c5d11e8c9c7abfb195806e475af 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -203,8 +203,8 @@ namespace {
 
   // Extensions. Configurable UCI options
   // Array index 0 is used at non-PV nodes, index 1 at PV nodes.
 
   // Extensions. Configurable UCI options
   // Array index 0 is used at non-PV nodes, index 1 at PV nodes.

-  Depth CheckExtension[2], SingleEvasionExtension[2], PawnPushTo7thExtension[2];
-  Depth PassedPawnExtension[2], PawnEndgameExtension[2], MateThreatExtension[2];
+  Depth CheckExtension[2], PawnPushTo7thExtension[2], PassedPawnExtension[2];
+  Depth PawnEndgameExtension[2], MateThreatExtension[2];

 
   // Minimum depth for use of singular extension
   const Depth SingularExtensionDepth[2] = { 8 * ONE_PLY /* non-PV */, 6 * ONE_PLY /* PV */};
 
   // Minimum depth for use of singular extension
   const Depth SingularExtensionDepth[2] = { 8 * ONE_PLY /* non-PV */, 6 * ONE_PLY /* PV */};


@@ -289,7 +289,7 @@ namespace {
   }
 
   template <NodeType PvNode>
   }
 
   template <NodeType PvNode>

-  Depth extension(const Position& pos, Move m, bool captureOrPromotion, bool moveIsCheck, bool singleEvasion, bool mateThreat, bool* dangerous);
+  Depth extension(const Position& pos, Move m, bool captureOrPromotion, bool moveIsCheck, bool mateThreat, bool* dangerous);

 
   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 check_is_dangerous(Position &pos, Move move, Value futilityBase, Value beta, Value *bValue);
   bool connected_moves(const Position& pos, Move m1, Move m2);


@@ -355,7 +355,6 @@ namespace {
 
       return rm != Rml.end() ? rm->pv[0] : MOVE_NONE;
     }
 
       return rm != Rml.end() ? rm->pv[0] : MOVE_NONE;
     }

-    int number_of_evasions() const { return (int)Rml.size(); }

 
     RootMoveList::iterator rm;
     bool firstCall;
 
     RootMoveList::iterator rm;
     bool firstCall;


@@ -501,8 +500,6 @@ bool think(Position& pos, bool infinite, bool ponder, int time[], int increment[
 
   CheckExtension[1]         = Options["Check Extension (PV nodes)"].value<Depth>();
   CheckExtension[0]         = Options["Check Extension (non-PV nodes)"].value<Depth>();
 
   CheckExtension[1]         = Options["Check Extension (PV nodes)"].value<Depth>();
   CheckExtension[0]         = Options["Check Extension (non-PV nodes)"].value<Depth>();

-  SingleEvasionExtension[1] = Options["Single Evasion Extension (PV nodes)"].value<Depth>();
-  SingleEvasionExtension[0] = Options["Single Evasion Extension (non-PV nodes)"].value<Depth>();

   PawnPushTo7thExtension[1] = Options["Pawn Push to 7th Extension (PV nodes)"].value<Depth>();
   PawnPushTo7thExtension[0] = Options["Pawn Push to 7th Extension (non-PV nodes)"].value<Depth>();
   PassedPawnExtension[1]    = Options["Passed Pawn Extension (PV nodes)"].value<Depth>();
   PawnPushTo7thExtension[1] = Options["Pawn Push to 7th Extension (PV nodes)"].value<Depth>();
   PawnPushTo7thExtension[0] = Options["Pawn Push to 7th Extension (non-PV nodes)"].value<Depth>();
   PassedPawnExtension[1]    = Options["Passed Pawn Extension (PV nodes)"].value<Depth>();


@@ -787,7 +784,7 @@ namespace {
     ValueType vt;
     Value bestValue, value, oldAlpha;
     Value refinedValue, nullValue, futilityBase, futilityValueScaled; // Non-PV specific
     ValueType vt;
     Value bestValue, value, oldAlpha;
     Value refinedValue, nullValue, futilityBase, futilityValueScaled; // Non-PV specific

-    bool isPvMove, isCheck, singleEvasion, singularExtensionNode, moveIsCheck, captureOrPromotion, dangerous;
+    bool isPvMove, isCheck, singularExtensionNode, moveIsCheck, captureOrPromotion, dangerous;

     bool mateThreat = false;
     int moveCount = 0, playedMoveCount = 0;
     int threadID = pos.thread();
     bool mateThreat = false;
     int moveCount = 0, playedMoveCount = 0;
     int threadID = pos.thread();


@@ -991,7 +988,6 @@ split_point_start: // At split points actual search starts from here
     MovePickerExt<SpNode, Root> mp(pos, ttMove, depth, H, ss, (PvNode ? -VALUE_INFINITE : beta));
     CheckInfo ci(pos);
     ss->bestMove = MOVE_NONE;
     MovePickerExt<SpNode, Root> mp(pos, ttMove, depth, H, ss, (PvNode ? -VALUE_INFINITE : beta));
     CheckInfo ci(pos);
     ss->bestMove = MOVE_NONE;

-    singleEvasion = !SpNode && isCheck && mp.number_of_evasions() == 1;

     futilityBase = ss->eval + ss->evalMargin;
     singularExtensionNode =   !Root
                            && !SpNode
     futilityBase = ss->eval + ss->evalMargin;
     singularExtensionNode =   !Root
                            && !SpNode


@@ -1053,7 +1049,7 @@ split_point_start: // At split points actual search starts from here
       captureOrPromotion = pos.move_is_capture_or_promotion(move);
 
       // Step 11. Decide the new search depth
       captureOrPromotion = pos.move_is_capture_or_promotion(move);
 
       // Step 11. Decide the new search depth

-      ext = extension<PvNode>(pos, move, captureOrPromotion, moveIsCheck, singleEvasion, mateThreat, &dangerous);
+      ext = extension<PvNode>(pos, move, captureOrPromotion, moveIsCheck, mateThreat, &dangerous);

 
       // Singular extension search. If all moves but one fail low on a search of (alpha-s, beta-s),
       // and just one fails high on (alpha, beta), then that move is singular and should be extended.
 
       // Singular extension search. If all moves but one fail low on a search of (alpha-s, beta-s),
       // and just one fails high on (alpha, beta), then that move is singular and should be extended.


@@ -1703,22 +1699,19 @@ split_point_start: // At split points actual search starts from here
   // extended, as example because the corresponding UCI option is set to zero,
   // the move is marked as 'dangerous' so, at least, we avoid to prune it.
   template <NodeType PvNode>
   // extended, as example because the corresponding UCI option is set to zero,
   // the move is marked as 'dangerous' so, at least, we avoid to prune it.
   template <NodeType PvNode>

-  Depth extension(const Position& pos, Move m, bool captureOrPromotion, bool moveIsCheck,
-                  bool singleEvasion, bool mateThreat, bool* dangerous) {
+  Depth extension(const Position& pos, Move m, bool captureOrPromotion,
+                  bool moveIsCheck, bool mateThreat, bool* dangerous) {

 
     assert(m != MOVE_NONE);
 
     Depth result = DEPTH_ZERO;
 
     assert(m != MOVE_NONE);
 
     Depth result = DEPTH_ZERO;

-    *dangerous = moveIsCheck | singleEvasion | mateThreat;
+    *dangerous = moveIsCheck | mateThreat;

 
     if (*dangerous)
     {
         if (moveIsCheck && pos.see_sign(m) >= 0)
             result += CheckExtension[PvNode];
 
 
     if (*dangerous)
     {
         if (moveIsCheck && pos.see_sign(m) >= 0)
             result += CheckExtension[PvNode];
 

-        if (singleEvasion)
-            result += SingleEvasionExtension[PvNode];
-

         if (mateThreat)
             result += MateThreatExtension[PvNode];
     }
         if (mateThreat)
             result += MateThreatExtension[PvNode];
     }

diff --git a/src/ucioption.cpp b/src/ucioption.cpp
index ab8137c4492b99a26508ef3eed2e4caa76313609..487778e5ad590b007dde1156f9a95eef6c09b559 100644 (file)
--- a/src/ucioption.cpp
+++ b/src/ucioption.cpp
@@ -81,8 +81,6 @@ void init_uci_options() {
   Options["Cowardice"] = Option(100, 0, 200);
   Options["Check Extension (PV nodes)"] = Option(2, 0, 2);
   Options["Check Extension (non-PV nodes)"] = Option(1, 0, 2);
   Options["Cowardice"] = Option(100, 0, 200);
   Options["Check Extension (PV nodes)"] = Option(2, 0, 2);
   Options["Check Extension (non-PV nodes)"] = Option(1, 0, 2);

-  Options["Single Evasion Extension (PV nodes)"] = Option(2, 0, 2);
-  Options["Single Evasion Extension (non-PV nodes)"] = Option(2, 0, 2);

   Options["Mate Threat Extension (PV nodes)"] = Option(2, 0, 2);
   Options["Mate Threat Extension (non-PV nodes)"] = Option(2, 0, 2);
   Options["Pawn Push to 7th Extension (PV nodes)"] = Option(1, 0, 2);
   Options["Mate Threat Extension (PV nodes)"] = Option(2, 0, 2);
   Options["Mate Threat Extension (non-PV nodes)"] = Option(2, 0, 2);
   Options["Pawn Push to 7th Extension (PV nodes)"] = Option(1, 0, 2);