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Remove Stack/thread dependence in movepick

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as a lower level routine, movepicker should not depend on the
search stack or the thread class, removing a circular dependency.
Instead of copying the search stack into the movepicker object,
as well as accessing the thread class for one of the histories,
pass the required fields explicitly to the constructor (removing
the need for thread.h and implicitly search.h in movepick.cpp).
The signature is thus longer, but more explicit:

Also some renaming of histories structures while there.

passed STC [-3,1], suggesting a small elo impact:

LLR: 3.13 (-2.94,2.94) [-3.00,1.00]
Total: 381053 W: 68071 L: 68551 D: 244431
elo =   -0.438 +-    0.660 LOS:    9.7%

No functional change.
This commit is contained in:
Joost VandeVondele
2017-06-30 17:20:00 +02:00
committed by Marco Costalba
parent 53c2d9df5e
commit b40e45c1cc
5 changed files with 71 additions and 87 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/search.cpp
+35 -34
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@@ -151,7 +151,7 @@ namespace {
Value value_to_tt(Value v, int ply);
Value value_from_tt(Value v, int ply);
void update_pv(Move* pv, Move move, Move* childPv);
void update_cm_stats(Stack* ss, Piece pc, Square s, int bonus);
void update_continuation_histories(Stack* ss, Piece pc, Square to, int bonus);
void update_stats(const Position& pos, Stack* ss, Move move, Move* quiets, int quietsCnt, int bonus);
} // namespace
@@ -192,13 +192,13 @@ void Search::clear() {
for (Thread* th : Threads)
{
th->counterMoves.fill(MOVE_NONE);
th->history.fill(0);
th->mainHistory.fill(0);
for (auto& to : th->counterMoveHistory)
for (auto& to : th->contHistory)
for (auto& h : to)
h.fill(0);
th->counterMoveHistory[NO_PIECE][0].fill(CounterMovePruneThreshold - 1);
th->contHistory[NO_PIECE][0].fill(CounterMovePruneThreshold - 1);
}
Threads.main()->callsCnt = 0;
@@ -334,7 +334,7 @@ void Thread::search() {
std::memset(ss-4, 0, 7 * sizeof(Stack));
for (int i = 4; i > 0; i--)
(ss-i)->history = &this->counterMoveHistory[NO_PIECE][0]; // Use as sentinel
(ss-i)->contHistory = &this->contHistory[NO_PIECE][0]; // Use as sentinel
bestValue = delta = alpha = -VALUE_INFINITE;
beta = VALUE_INFINITE;
@@ -591,7 +591,7 @@ namespace {
assert(0 <= ss->ply && ss->ply < MAX_PLY);
ss->currentMove = (ss+1)->excludedMove = bestMove = MOVE_NONE;
ss->history = &thisThread->counterMoveHistory[NO_PIECE][0];
ss->contHistory = &thisThread->contHistory[NO_PIECE][0];
(ss+2)->killers[0] = (ss+2)->killers[1] = MOVE_NONE;
Square prevSq = to_sq((ss-1)->currentMove);
@@ -623,14 +623,14 @@ namespace {
// Extra penalty for a quiet TT move in previous ply when it gets refuted
if ((ss-1)->moveCount == 1 && !pos.captured_piece())
update_cm_stats(ss-1, pos.piece_on(prevSq), prevSq, -stat_bonus(depth + ONE_PLY));
update_continuation_histories(ss-1, pos.piece_on(prevSq), prevSq, -stat_bonus(depth + ONE_PLY));
}
// Penalty for a quiet ttMove that fails low
else if (!pos.capture_or_promotion(ttMove))
{
int penalty = -stat_bonus(depth);
thisThread->history.update(pos.side_to_move(), ttMove, penalty);
update_cm_stats(ss, pos.moved_piece(ttMove), to_sq(ttMove), penalty);
thisThread->mainHistory.update(pos.side_to_move(), ttMove, penalty);
update_continuation_histories(ss, pos.moved_piece(ttMove), to_sq(ttMove), penalty);
}
}
return ttValue;
@@ -734,7 +734,7 @@ namespace {
Depth R = ((823 + 67 * depth / ONE_PLY) / 256 + std::min((eval - beta) / PawnValueMg, 3)) * ONE_PLY;
ss->currentMove = MOVE_NULL;
ss->history = &thisThread->counterMoveHistory[NO_PIECE][0];
ss->contHistory = &thisThread->contHistory[NO_PIECE][0];
pos.do_null_move(st);
Value nullValue = depth-R < ONE_PLY ? -qsearch<NonPV, false>(pos, ss+1, -beta, -beta+1)
@@ -776,7 +776,7 @@ namespace {
if (pos.legal(move))
{
ss->currentMove = move;
ss->history = &thisThread->counterMoveHistory[pos.moved_piece(move)][to_sq(move)];
ss->contHistory = &thisThread->contHistory[pos.moved_piece(move)][to_sq(move)];
assert(depth >= 5 * ONE_PLY);
pos.do_move(move, st);
@@ -801,11 +801,10 @@ namespace {
moves_loop: // When in check search starts from here
const PieceToHistory& cmh = *(ss-1)->history;
const PieceToHistory& fmh = *(ss-2)->history;
const PieceToHistory& fm2 = *(ss-4)->history;
const PieceToHistory* contHist[] = { (ss-1)->contHistory, (ss-2)->contHistory, nullptr, (ss-4)->contHistory };
Move countermove = thisThread->counterMoves[pos.piece_on(prevSq)][prevSq];
MovePicker mp(pos, ttMove, depth, ss);
MovePicker mp(pos, ttMove, depth, &thisThread->mainHistory, contHist, countermove, ss->killers);
value = bestValue; // Workaround a bogus 'uninitialized' warning under gcc
improving = ss->staticEval >= (ss-2)->staticEval
/* || ss->staticEval == VALUE_NONE Already implicit in the previous condition */
@@ -907,8 +906,8 @@ moves_loop: // When in check search starts from here
// Countermoves based pruning
if ( lmrDepth < 3
&& (cmh[moved_piece][to_sq(move)] < CounterMovePruneThreshold)
&& (fmh[moved_piece][to_sq(move)] < CounterMovePruneThreshold))
&& (*contHist[0])[moved_piece][to_sq(move)] < CounterMovePruneThreshold
&& (*contHist[1])[moved_piece][to_sq(move)] < CounterMovePruneThreshold)
continue;
// Futility pruning: parent node
@@ -943,7 +942,7 @@ moves_loop: // When in check search starts from here
// Update the current move (this must be done after singular extension search)
ss->currentMove = move;
ss->history = &thisThread->counterMoveHistory[moved_piece][to_sq(move)];
ss->contHistory = &thisThread->contHistory[moved_piece][to_sq(move)];
// Step 14. Make the move
pos.do_move(move, st, givesCheck);
@@ -975,11 +974,11 @@ moves_loop: // When in check search starts from here
&& !pos.see_ge(make_move(to_sq(move), from_sq(move))))
r -= 2 * ONE_PLY;
ss->statScore = cmh[moved_piece][to_sq(move)]
+ fmh[moved_piece][to_sq(move)]
+ fm2[moved_piece][to_sq(move)]
+ thisThread->history[~pos.side_to_move()][from_to(move)]
- 4000; // Correction factor
ss->statScore = thisThread->mainHistory[~pos.side_to_move()][from_to(move)]
+ (*contHist[0])[moved_piece][to_sq(move)]
+ (*contHist[1])[moved_piece][to_sq(move)]
+ (*contHist[3])[moved_piece][to_sq(move)]
- 4000;
// Decrease/increase reduction by comparing opponent's stat score
if (ss->statScore > 0 && (ss-1)->statScore < 0)
@@ -1115,13 +1114,13 @@ moves_loop: // When in check search starts from here
// Extra penalty for a quiet TT move in previous ply when it gets refuted
if ((ss-1)->moveCount == 1 && !pos.captured_piece())
update_cm_stats(ss-1, pos.piece_on(prevSq), prevSq, -stat_bonus(depth + ONE_PLY));
update_continuation_histories(ss-1, pos.piece_on(prevSq), prevSq, -stat_bonus(depth + ONE_PLY));
}
// Bonus for prior countermove that caused the fail low
else if ( depth >= 3 * ONE_PLY
&& !pos.captured_piece()
&& is_ok((ss-1)->currentMove))
update_cm_stats(ss-1, pos.piece_on(prevSq), prevSq, stat_bonus(depth));
update_continuation_histories(ss-1, pos.piece_on(prevSq), prevSq, stat_bonus(depth));
if (!excludedMove)
tte->save(posKey, value_to_tt(bestValue, ss->ply),
@@ -1241,7 +1240,8 @@ moves_loop: // When in check search starts from here
// to search the moves. Because the depth is <= 0 here, only captures,
// queen promotions and checks (only if depth >= DEPTH_QS_CHECKS) will
// be generated.
MovePicker mp(pos, ttMove, depth, to_sq((ss-1)->currentMove));
const PieceToHistory* contHist[4] = {};
MovePicker mp(pos, ttMove, depth, &pos.this_thread()->mainHistory, contHist, to_sq((ss-1)->currentMove));
// Loop through the moves until no moves remain or a beta cutoff occurs
while ((move = mp.next_move()) != MOVE_NONE)
@@ -1385,13 +1385,14 @@ moves_loop: // When in check search starts from here
}
// update_cm_stats() updates countermove and follow-up move history
// update_continuation_histories() updates histories of the move pairs formed
// by moves at ply -1, -2, and -4 with current move.
void update_cm_stats(Stack* ss, Piece pc, Square s, int bonus) {
void update_continuation_histories(Stack* ss, Piece pc, Square to, int bonus) {
for (int i : {1, 2, 4})
if (is_ok((ss-i)->currentMove))
(ss-i)->history->update(pc, s, bonus);
(ss-i)->contHistory->update(pc, to, bonus);
}
@@ -1408,20 +1409,20 @@ moves_loop: // When in check search starts from here
Color c = pos.side_to_move();
Thread* thisThread = pos.this_thread();
thisThread->history.update(c, move, bonus);
update_cm_stats(ss, pos.moved_piece(move), to_sq(move), bonus);
thisThread->mainHistory.update(c, move, bonus);
update_continuation_histories(ss, pos.moved_piece(move), to_sq(move), bonus);
if (is_ok((ss-1)->currentMove))
{
Square prevSq = to_sq((ss-1)->currentMove);
thisThread->counterMoves[pos.piece_on(prevSq)][prevSq]=move;
thisThread->counterMoves[pos.piece_on(prevSq)][prevSq] = move;
}
// Decrease all the other played quiet moves
for (int i = 0; i < quietsCnt; ++i)
{
thisThread->history.update(c, quiets[i], -bonus);
update_cm_stats(ss, pos.moved_piece(quiets[i]), to_sq(quiets[i]), -bonus);
thisThread->mainHistory.update(c, quiets[i], -bonus);
update_continuation_histories(ss, pos.moved_piece(quiets[i]), to_sq(quiets[i]), -bonus);
}
}