X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovepick.h;h=97b1b3abb7f1aaeded105cb068e47b6ceab15c69;hp=36bf58f63ac329821156ea8539a7df20488e63af;hb=99d914985f6ddb1ee22b232d41f17a35e1d34f89;hpb=01ee509a5c33e11d7d62d2f325f55720d8be9cfb

diff --git a/src/movepick.h b/src/movepick.h
index 36bf58f6..97b1b3ab 100644
--- a/src/movepick.h
+++ b/src/movepick.h
@@ -2,7 +2,7 @@
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
   Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
-  Copyright (C) 2015-2016 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
+  Copyright (C) 2015-2017 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -21,78 +21,77 @@
 #ifndef MOVEPICK_H_INCLUDED
 #define MOVEPICK_H_INCLUDED
 
-#include <algorithm> // For std::max
 #include <cstring>   // For std::memset
 
 #include "movegen.h"
 #include "position.h"
-#include "search.h"
 #include "types.h"
 
 
-/// The Stats struct stores moves statistics. According to the template parameter
-/// the class can store History and Countermoves. History records how often
-/// different moves have been successful or unsuccessful during the current search
-/// and is used for reduction and move ordering decisions.
-/// Countermoves store the move that refute a previous one. Entries are stored
-/// using only the moving piece and destination square, hence two moves with
-/// different origin but same destination and piece will be considered identical.
-template<typename T, bool CM = false>
-struct Stats {
+/// HistoryStats records how often quiet moves have been successful or unsuccessful
+/// during the current search, and is used for reduction and move ordering decisions.
+struct HistoryStats {
 
-  static const Value Max = Value(1 << 28);
+  static const int Max = 1 << 28;
 
-  const T* operator[](Piece pc) const { return table[pc]; }
-  T* operator[](Piece pc) { return table[pc]; }
+  int get(Color c, Move m) const { return table[c][from_sq(m)][to_sq(m)]; }
   void clear() { std::memset(table, 0, sizeof(table)); }
+  void update(Color c, Move m, int v) {
 
-  void update(Piece pc, Square to, Move m) { table[pc][to] = m; }
+    Square from = from_sq(m);
+    Square to = to_sq(m);
 
-  void update(Piece pc, Square to, Value v) {
+    const int D = 324;
 
-    if (abs(int(v)) >= 324)
-        return;
+    assert(abs(v) <= D); // Consistency check for below formula
 
-    table[pc][to] -= table[pc][to] * abs(int(v)) / (CM ? 936 : 324);
-    table[pc][to] += int(v) * 32;
+    table[c][from][to] -= table[c][from][to] * abs(v) / D;
+    table[c][from][to] += v * 32;
   }
 
 private:
-  T table[PIECE_NB][SQUARE_NB];
+  int table[COLOR_NB][SQUARE_NB][SQUARE_NB];
 };
 
-typedef Stats<Move> MoveStats;
-typedef Stats<Value, false> HistoryStats;
-typedef Stats<Value,  true> CounterMoveStats;
-typedef Stats<CounterMoveStats> CounterMoveHistoryStats;
-
-struct FromToStats {
 
-    Value get(Color c, Move m) const { return table[c][from_sq(m)][to_sq(m)]; }
-    void clear() { std::memset(table, 0, sizeof(table)); }
+/// A template struct, used to generate MoveStats and CounterMoveHistoryStats:
+/// MoveStats store the move that refute a previous one.
+/// CounterMoveHistoryStats is like HistoryStats, but with two consecutive moves.
+/// Entries are stored using only the moving piece and destination square, hence
+/// two moves with different origin but same destination and piece will be
+/// considered identical.
+template<typename T>
+struct Stats {
+  const T* operator[](Piece pc) const { return table[pc]; }
+  T* operator[](Piece pc) { return table[pc]; }
+  void clear() { std::memset(table, 0, sizeof(table)); }
+  void update(Piece pc, Square to, Move m) { table[pc][to] = m; }
+  void update(Piece pc, Square to, int v) {
 
-    void update(Color c, Move m, Value v)
-    {
-        if (abs(int(v)) >= 324)
-            return;
+    const int D = 936;
 
-        Square f = from_sq(m);
-        Square t = to_sq(m);
+    assert(abs(v) <= D); // Consistency check for below formula
 
-        table[c][f][t] -= table[c][f][t] * abs(int(v)) / 324;
-        table[c][f][t] += int(v) * 32;
-    }
+    table[pc][to] -= table[pc][to] * abs(v) / D;
+    table[pc][to] += v * 32;
+  }
 
 private:
-    Value table[COLOR_NB][SQUARE_NB][SQUARE_NB];
+  T table[PIECE_NB][SQUARE_NB];
 };
 
+typedef Stats<Move> MoveStats;
+typedef Stats<int> CounterMoveStats;
+typedef Stats<CounterMoveStats> CounterMoveHistoryStats;
+
+
 /// MovePicker class is used to pick one pseudo legal move at a time from the
 /// current position. The most important method is next_move(), which returns a
 /// new pseudo legal move each time it is called, until there are no moves left,
 /// when MOVE_NONE is returned. In order to improve the efficiency of the alpha
 /// beta algorithm, MovePicker attempts to return the moves which are most likely
 /// to get a cut-off first.
+namespace Search { struct Stack; }
 
 class MovePicker {
 public:
@@ -103,7 +102,7 @@ public:
   MovePicker(const Position&, Move, Depth, Square);
   MovePicker(const Position&, Move, Depth, Search::Stack*);
 
-  Move next_move();
+  Move next_move(bool skipQuiets = false);
 
 private:
   template<GenType> void score();
@@ -112,13 +111,14 @@ private:
 
   const Position& pos;
   const Search::Stack* ss;
+  Move killers[2];
   Move countermove;
   Depth depth;
   Move ttMove;
   Square recaptureSquare;
   Value threshold;
   int stage;
-  ExtMove* cur, *endMoves, *endBadCaptures;
+  ExtMove *cur, *endMoves, *endBadCaptures;
   ExtMove moves[MAX_MOVES];
 };