X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fmovepick.cpp;h=cd8f5da675c966147d03354ebf841a2c3f8775ce;hb=4fc773454759081c2cd921e460d542f2dfd4aa24;hp=005f85203e6a493f6540d2281b0c78a667bedf4b;hpb=e40b06a0503b44bae5508a371d961914828214b6;p=stockfish
diff --git a/src/movepick.cpp b/src/movepick.cpp
index 005f8520..cd8f5da6 100644
--- a/src/movepick.cpp
+++ b/src/movepick.cpp
@@ -1,7 +1,7 @@
/*
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) 2008-2013 Marco Costalba, Joona Kiiski, 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
@@ -18,10 +18,8 @@
along with this program. If not, see .
*/
-#include
#include
-#include "movegen.h"
#include "movepick.h"
#include "thread.h"
@@ -37,6 +35,20 @@ namespace {
STOP
};
+ // Our insertion sort, guaranteed to be stable, as is needed
+ void insertion_sort(MoveStack* begin, MoveStack* end)
+ {
+ MoveStack tmp, *p, *q;
+
+ for (p = begin + 1; p < end; ++p)
+ {
+ tmp = *p;
+ for (q = p; q != begin && *(q-1) < tmp; --q)
+ *q = *(q-1);
+ *q = tmp;
+ }
+ }
+
// Unary predicate used by std::partition to split positive scores from remaining
// ones so to sort separately the two sets, and with the second sort delayed.
inline bool has_positive_score(const MoveStack& ms) { return ms.score > 0; }
@@ -58,45 +70,43 @@ namespace {
/// search captures, promotions and some checks) and about how important good
/// move ordering is at the current node.
-MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const History& h,
- Search::Stack* s, Value beta) : pos(p), H(h), depth(d) {
+MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats& h, Move* cm,
+ Search::Stack* s, Value beta) : pos(p), history(h), depth(d) {
assert(d > DEPTH_ZERO);
captureThreshold = 0;
cur = end = moves;
endBadCaptures = moves + MAX_MOVES - 1;
+ countermoves = cm;
ss = s;
- if (p.in_check())
+ if (p.checkers())
phase = EVASION;
else
{
phase = MAIN_SEARCH;
- killers[0].move = ss->killers[0];
- killers[1].move = ss->killers[1];
-
// Consider sligtly negative captures as good if at low depth and far from beta
- if (ss && ss->eval < beta - PawnValueMg && d < 3 * ONE_PLY)
+ if (ss->staticEval < beta - PawnValueMg && d < 3 * ONE_PLY)
captureThreshold = -PawnValueMg;
// Consider negative captures as good if still enough to reach beta
- else if (ss && ss->eval > beta)
- captureThreshold = beta - ss->eval;
+ else if (ss->staticEval > beta)
+ captureThreshold = beta - ss->staticEval;
}
ttMove = (ttm && pos.is_pseudo_legal(ttm) ? ttm : MOVE_NONE);
end += (ttMove != MOVE_NONE);
}
-MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const History& h,
- Square sq) : pos(p), H(h), cur(moves), end(moves) {
+MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats& h,
+ Square sq) : pos(p), history(h), cur(moves), end(moves) {
assert(d <= DEPTH_ZERO);
- if (p.in_check())
+ if (p.checkers())
phase = EVASION;
else if (d > DEPTH_QS_NO_CHECKS)
@@ -123,10 +133,10 @@ MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const History& h,
end += (ttMove != MOVE_NONE);
}
-MovePicker::MovePicker(const Position& p, Move ttm, const History& h, PieceType pt)
- : pos(p), H(h), cur(moves), end(moves) {
+MovePicker::MovePicker(const Position& p, Move ttm, const HistoryStats& h, PieceType pt)
+ : pos(p), history(h), cur(moves), end(moves) {
- assert(!pos.in_check());
+ assert(!pos.checkers());
phase = PROBCUT;
@@ -141,12 +151,10 @@ MovePicker::MovePicker(const Position& p, Move ttm, const History& h, PieceType
}
-/// MovePicker::score_captures(), MovePicker::score_noncaptures() and
-/// MovePicker::score_evasions() assign a numerical move ordering score
-/// to each move in a move list. The moves with highest scores will be
-/// picked first by next_move().
-
-void MovePicker::score_captures() {
+/// score() assign a numerical move ordering score to each move in a move list.
+/// The moves with highest scores will be picked first.
+template<>
+void MovePicker::score() {
// Winning and equal captures in the main search are ordered by MVV/LVA.
// Suprisingly, this appears to perform slightly better than SEE based
// move ordering. The reason is probably that in a position with a winning
@@ -169,47 +177,50 @@ void MovePicker::score_captures() {
- type_of(pos.piece_moved(m));
if (type_of(m) == PROMOTION)
- it->score += PieceValue[MG][promotion_type(m)];
+ it->score += PieceValue[MG][promotion_type(m)] - PieceValue[MG][PAWN];
+
+ else if (type_of(m) == ENPASSANT)
+ it->score += PieceValue[MG][PAWN];
}
}
-void MovePicker::score_noncaptures() {
+template<>
+void MovePicker::score() {
Move m;
for (MoveStack* it = moves; it != end; ++it)
{
m = it->move;
- it->score = H.value(pos.piece_moved(m), to_sq(m));
+ it->score = history[pos.piece_moved(m)][to_sq(m)];
}
}
-void MovePicker::score_evasions() {
+template<>
+void MovePicker::score() {
// Try good captures ordered by MVV/LVA, then non-captures if destination square
// is not under attack, ordered by history value, then bad-captures and quiet
// moves with a negative SEE. This last group is ordered by the SEE score.
Move m;
int seeScore;
- if (end < moves + 2)
- return;
-
for (MoveStack* it = moves; it != end; ++it)
{
m = it->move;
if ((seeScore = pos.see_sign(m)) < 0)
- it->score = seeScore - History::MaxValue; // Be sure we are at the bottom
+ it->score = seeScore - HistoryStats::Max; // At the bottom
+
else if (pos.is_capture(m))
it->score = PieceValue[MG][pos.piece_on(to_sq(m))]
- - type_of(pos.piece_moved(m)) + History::MaxValue;
+ - type_of(pos.piece_moved(m)) + HistoryStats::Max;
else
- it->score = H.value(pos.piece_moved(m), to_sq(m));
+ it->score = history[pos.piece_moved(m)][to_sq(m)];
}
}
-/// MovePicker::generate_next() generates, scores and sorts the next bunch of moves,
-/// when there are no more moves to try for the current phase.
+/// generate_next() generates, scores and sorts the next bunch of moves, when
+/// there are no more moves to try for the current phase.
void MovePicker::generate_next() {
@@ -219,26 +230,39 @@ void MovePicker::generate_next() {
case CAPTURES_S1: case CAPTURES_S3: case CAPTURES_S4: case CAPTURES_S5: case CAPTURES_S6:
end = generate(pos, moves);
- score_captures();
+ score();
return;
case KILLERS_S1:
cur = killers;
end = cur + 2;
+
+ killers[0].move = ss->killers[0];
+ killers[1].move = ss->killers[1];
+ killers[2].move = killers[3].move = MOVE_NONE;
+
+ // Be sure countermoves are different from killers
+ for (int i = 0; i < 2; i++)
+ if (countermoves[i] != cur->move && countermoves[i] != (cur+1)->move)
+ (end++)->move = countermoves[i];
+
+ if (countermoves[1] && countermoves[1] == countermoves[0]) // Due to SMP races
+ killers[3].move = MOVE_NONE;
+
return;
case QUIETS_1_S1:
endQuiets = end = generate(pos, moves);
- score_noncaptures();
+ score();
end = std::partition(cur, end, has_positive_score);
- sort(cur, end);
+ insertion_sort(cur, end);
return;
case QUIETS_2_S1:
cur = end;
end = endQuiets;
if (depth >= 3 * ONE_PLY)
- sort(cur, end);
+ insertion_sort(cur, end);
return;
case BAD_CAPTURES_S1:
@@ -249,7 +273,8 @@ void MovePicker::generate_next() {
case EVASIONS_S2:
end = generate(pos, moves);
- score_evasions();
+ if (end > moves + 1)
+ score();
return;
case QUIET_CHECKS_S3:
@@ -268,11 +293,10 @@ void MovePicker::generate_next() {
}
-/// MovePicker::next_move() is the most important method of the MovePicker class.
-/// It returns a new pseudo legal move every time it is called, until there
-/// are no more moves left. It picks the move with the biggest score from a list
-/// of generated moves taking care not to return the tt move if has already been
-/// searched previously.
+/// next_move() is the most important method of the MovePicker class. It returns
+/// a new pseudo legal move every time is called, until there are no more moves
+/// left. It picks the move with the biggest score from a list of generated moves
+/// taking care not returning the ttMove if has already been searched previously.
template<>
Move MovePicker::next_move() {
@@ -316,7 +340,9 @@ Move MovePicker::next_move() {
move = (cur++)->move;
if ( move != ttMove
&& move != killers[0].move
- && move != killers[1].move)
+ && move != killers[1].move
+ && move != killers[2].move
+ && move != killers[3].move)
return move;
break;
@@ -359,6 +385,6 @@ Move MovePicker::next_move() {
/// Version of next_move() to use at split point nodes where the move is grabbed
/// from the split point's shared MovePicker object. This function is not thread
-/// safe so should be lock protected by the caller.
+/// safe so must be lock protected by the caller.
template<>
-Move MovePicker::next_move() { return ss->sp->mp->next_move(); }
+Move MovePicker::next_move() { return ss->splitPoint->movePicker->next_move(); }