X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fmovepick.h;h=f9403f0f63940f446d974434018c534c3a022c97;hb=b2961aded6cd2807a8c4899e090e28fcb2161310;hp=5b40ded8e0b5911636e9651f0b81d380e186d198;hpb=30c2e3828a5ea143e6190680dcd8e9d93fd17840;p=stockfish
diff --git a/src/movepick.h b/src/movepick.h
index 5b40ded8..f9403f0f 100644
--- a/src/movepick.h
+++ b/src/movepick.h
@@ -1,7 +1,8 @@
/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2015-2018 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
@@ -17,49 +18,89 @@
along with this program. If not, see .
*/
-#if !defined MOVEPICK_H_INCLUDED
+#ifndef MOVEPICK_H_INCLUDED
#define MOVEPICK_H_INCLUDED
-#include // For std::max
-#include // For memset
+#include
+#include
+#include
#include "movegen.h"
#include "position.h"
-#include "search.h"
#include "types.h"
+/// StatsEntry stores the stat table value. It is usually a number but could
+/// be a move or even a nested history. We use a class instead of naked value
+/// to directly call history update operator<<() on the entry so to use stats
+/// tables at caller sites as simple multi-dim arrays.
+template
+class StatsEntry {
-/// The Stats struct stores moves statistics. According to the template parameter
-/// the class can store both History and Gains type statistics. History records
-/// how often different moves have been successful or unsuccessful during the
-/// current search and is used for reduction and move ordering decisions. Gains
-/// records the move's best evaluation gain from one ply to the next and is used
-/// for pruning decisions. Entries are stored according only to moving piece and
-/// destination square, in particular two moves with different origin but same
-/// destination and same piece will be considered identical.
-template
-struct Stats {
+ static const bool IsInt = std::is_integral::value;
+ typedef typename std::conditional::type TT;
- static const Value Max = Value(2000);
+ T entry;
- const Value* operator[](Piece p) const { return &table[p][0]; }
- void clear() { memset(table, 0, sizeof(table)); }
+public:
+ T* get() { return &entry; }
+ void operator=(const T& v) { entry = v; }
+ operator TT() const { return entry; }
+
+ void operator<<(int bonus) {
- void update(Piece p, Square to, Value v) {
+ assert(abs(bonus) <= D); // Ensure range is [-W * D, W * D]
+ assert(abs(W * D) < std::numeric_limits::max()); // Ensure we don't overflow
- if (Gain)
- table[p][to] = std::max(v, table[p][to] - 1);
+ entry += bonus * W - entry * abs(bonus) / D;
- else if (abs(table[p][to] + v) < Max)
- table[p][to] += v;
+ assert(abs(entry) <= W * D);
}
+};
-private:
- Value table[PIECE_NB][SQUARE_NB];
+/// Stats is a generic N-dimensional array used to store various statistics.
+/// The first template T parameter is the base type of the array, the W parameter
+/// is the weight applied to the bonuses when we update values with the << operator,
+/// the D parameter limits the range of updates (range is [-W * D, W * D]), and
+/// the last parameters (Size and Sizes) encode the dimensions of the array.
+template
+struct Stats : public std::array, Size>
+{
+ T* get() { return this->at(0).get(); }
+
+ void fill(const T& v) {
+ T* p = get();
+ std::fill(p, p + sizeof(*this) / sizeof(*p), v);
+ }
+};
+
+template
+struct Stats : public std::array, Size> {
+ T* get() { return this->at(0).get(); }
};
-typedef Stats History;
-typedef Stats Gains;
+/// Different tables use different W/D parameter, name them to ease readibility
+enum StatsParams { W2 = 2, W32 = 32, D324 = 324, D936 = 936, NOT_USED = 0 };
+
+/// ButterflyHistory records how often quiet moves have been successful or
+/// unsuccessful during the current search, and is used for reduction and move
+/// ordering decisions. It uses 2 tables (one for each color) indexed by
+/// the move's from and to squares, see chessprogramming.wikispaces.com/Butterfly+Boards
+typedef Stats ButterflyHistory;
+
+/// CounterMoveHistory stores counter moves indexed by [piece][to] of the previous
+/// move, see chessprogramming.wikispaces.com/Countermove+Heuristic
+typedef Stats CounterMoveHistory;
+
+/// CapturePieceToHistory is addressed by a move's [piece][to][captured piece type]
+typedef Stats CapturePieceToHistory;
+
+/// PieceToHistory is like ButterflyHistory but is addressed by a move's [piece][to]
+typedef Stats PieceToHistory;
+
+/// ContinuationHistory is the combined history of a given pair of moves, usually
+/// the current one given a previous one. The nested history table is based on
+/// PieceToHistory instead of ButterflyBoards.
+typedef Stats ContinuationHistory;
/// MovePicker class is used to pick one pseudo legal move at a time from the
@@ -70,29 +111,30 @@ typedef Stats Gains;
/// to get a cut-off first.
class MovePicker {
-
- MovePicker& operator=(const MovePicker&); // Silence a warning under MSVC
-
public:
- MovePicker(const Position&, Move, Depth, const History&, Search::Stack*, Value);
- MovePicker(const Position&, Move, Depth, const History&, Square);
- MovePicker(const Position&, Move, const History&, PieceType);
- template Move next_move();
+ MovePicker(const MovePicker&) = delete;
+ MovePicker& operator=(const MovePicker&) = delete;
+ MovePicker(const Position&, Move, Value, const CapturePieceToHistory*);
+ MovePicker(const Position&, Move, Depth, const ButterflyHistory*, const CapturePieceToHistory*, Square);
+ MovePicker(const Position&, Move, Depth, const ButterflyHistory*, const CapturePieceToHistory*, const PieceToHistory**, Move, Move*);
+ Move next_move(bool skipQuiets = false);
private:
template void score();
- void generate_next();
+ ExtMove* begin() { return cur; }
+ ExtMove* end() { return endMoves; }
const Position& pos;
- const History& Hist;
- Search::Stack* ss;
- Depth depth;
- Move ttMove;
- MoveStack killers[2];
+ const ButterflyHistory* mainHistory;
+ const CapturePieceToHistory* captureHistory;
+ const PieceToHistory** contHistory;
+ Move ttMove, refutations[3];
+ ExtMove *cur, *endMoves, *endBadCaptures;
+ int stage;
Square recaptureSquare;
- int captureThreshold, phase;
- MoveStack *cur, *end, *endQuiets, *endBadCaptures;
- MoveStack moves[MAX_MOVES];
+ Value threshold;
+ Depth depth;
+ ExtMove moves[MAX_MOVES];
};
-#endif // !defined(MOVEPICK_H_INCLUDED)
+#endif // #ifndef MOVEPICK_H_INCLUDED