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Merge branch 'master' into tools

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This commit is contained in:
Tomasz Sobczyk
2021-05-24 11:32:58 +02:00
parent cbd72299c1 a2f01c07eb
commit 127c1f2fe2
26 changed files with 432 additions and 426 deletions
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src/search.cpp
+23 -51
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@@ -60,7 +60,7 @@ namespace {
// Futility margin
Value futility_margin(Depth d, bool improving) {
return Value(234 * (d - improving));
return Value(214 * (d - improving));
}
// Reductions lookup table, initialized at startup
@@ -68,7 +68,7 @@ namespace {
Depth reduction(bool i, Depth d, int mn) {
int r = Reductions[d] * Reductions[mn];
return (r + 503) / 1024 + (!i && r > 915);
return (r + 534) / 1024 + (!i && r > 904);
}
constexpr int futility_move_count(bool improving, Depth depth) {
@@ -77,7 +77,7 @@ namespace {
// History and stats update bonus, based on depth
int stat_bonus(Depth d) {
return d > 14 ? 66 : 6 * d * d + 231 * d - 206;
return d > 14 ? 73 : 6 * d * d + 229 * d - 215;
}
// Add a small random component to draw evaluations to avoid 3-fold blindness
@@ -374,7 +374,7 @@ void Thread::search() {
// Start with a small aspiration window and, in the case of a fail
// high/low, re-search with a bigger window until we don't fail
// high/low anymore.
failedHighCnt = 0;
int failedHighCnt = 0;
while (true)
{
Depth adjustedDepth = std::max(1, rootDepth - failedHighCnt - searchAgainCounter);
@@ -764,7 +764,7 @@ namespace {
if ((ss-1)->currentMove != MOVE_NULL)
ss->staticEval = eval = evaluate(pos);
else
ss->staticEval = eval = -(ss-1)->staticEval + 2 * Tempo;
ss->staticEval = eval = -(ss-1)->staticEval;
// Save static evaluation into transposition table
tte->save(posKey, VALUE_NONE, ss->ttPv, BOUND_NONE, DEPTH_NONE, MOVE_NONE, eval);
@@ -773,7 +773,7 @@ namespace {
// Use static evaluation difference to improve quiet move ordering
if (is_ok((ss-1)->currentMove) && !(ss-1)->inCheck && !priorCapture)
{
int bonus = std::clamp(-depth * 4 * int((ss-1)->staticEval + ss->staticEval - 2 * Tempo), -1000, 1000);
int bonus = std::clamp(-depth * 4 * int((ss-1)->staticEval + ss->staticEval), -1000, 1000);
thisThread->mainHistory[~us][from_to((ss-1)->currentMove)] << bonus;
}
@@ -795,10 +795,10 @@ namespace {
// Step 8. Null move search with verification search (~40 Elo)
if ( !PvNode
&& (ss-1)->currentMove != MOVE_NULL
&& (ss-1)->statScore < 24185
&& (ss-1)->statScore < 23767
&& eval >= beta
&& eval >= ss->staticEval
&& ss->staticEval >= beta - 24 * depth - 34 * improving + 162 * ss->ttPv + 159
&& ss->staticEval >= beta - 20 * depth - 22 * improving + 168 * ss->ttPv + 159
&& !excludedMove
&& pos.non_pawn_material(us)
&& (ss->ply >= thisThread->nmpMinPly || us != thisThread->nmpColor))
@@ -806,7 +806,7 @@ namespace {
assert(eval - beta >= 0);
// Null move dynamic reduction based on depth and value
Depth R = (1062 + 68 * depth) / 256 + std::min(int(eval - beta) / 190, 3);
Depth R = (1090 + 81 * depth) / 256 + std::min(int(eval - beta) / 205, 3);
ss->currentMove = MOVE_NULL;
ss->continuationHistory = &thisThread->continuationHistory[0][0][NO_PIECE][0];
@@ -844,7 +844,7 @@ namespace {
probCutBeta = beta + 209 - 44 * improving;
// Step 9. ProbCut (~10 Elo)
// Step 9. ProbCut (~4 Elo)
// If we have a good enough capture and a reduced search returns a value
// much above beta, we can (almost) safely prune the previous move.
if ( !PvNode
@@ -859,16 +859,6 @@ namespace {
&& ttValue != VALUE_NONE
&& ttValue < probCutBeta))
{
// if ttMove is a capture and value from transposition table is good enough produce probCut
// cutoff without digging into actual probCut search
if ( ss->ttHit
&& tte->depth() >= depth - 3
&& ttValue != VALUE_NONE
&& ttValue >= probCutBeta
&& ttMove
&& pos.capture_or_promotion(ttMove))
return probCutBeta;
assert(probCutBeta < VALUE_INFINITE);
MovePicker mp(pos, ttMove, probCutBeta - ss->staticEval, &captureHistory);
@@ -929,7 +919,7 @@ moves_loop: // When in check, search starts from here
ttCapture = ttMove && pos.capture_or_promotion(ttMove);
// Step 11. A small Probcut idea, when we are in check
probCutBeta = beta + 400;
probCutBeta = beta + 409;
if ( ss->inCheck
&& !PvNode
&& depth >= 4
@@ -1034,8 +1024,8 @@ moves_loop: // When in check, search starts from here
}
else
{
// Countermoves based pruning (~20 Elo)
if ( lmrDepth < 4 + ((ss-1)->statScore > 0 || (ss-1)->moveCount == 1)
// Continuation history based pruning (~20 Elo)
if ( lmrDepth < 5
&& (*contHist[0])[movedPiece][to_sq(move)] < CounterMovePruneThreshold
&& (*contHist[1])[movedPiece][to_sq(move)] < CounterMovePruneThreshold)
continue;
@@ -1083,7 +1073,7 @@ moves_loop: // When in check, search starts from here
{
extension = 1;
singularQuietLMR = !ttCapture;
if (!PvNode && value < singularBeta - 140)
if (!PvNode && value < singularBeta - 93)
extension = 2;
}
@@ -1131,21 +1121,18 @@ moves_loop: // When in check, search starts from here
if ( depth >= 3
&& moveCount > 1 + 2 * rootNode
&& ( !captureOrPromotion
|| moveCountPruning
|| ss->staticEval + PieceValue[EG][pos.captured_piece()] <= alpha
|| cutNode
|| (!PvNode && !formerPv && captureHistory[movedPiece][to_sq(move)][type_of(pos.captured_piece())] < 3678)
|| thisThread->ttHitAverage < 432 * TtHitAverageResolution * TtHitAverageWindow / 1024)
|| (!PvNode && !formerPv))
&& (!PvNode || ss->ply > 1 || thisThread->id() % 4 != 3))
{
Depth r = reduction(improving, depth, moveCount);
// Decrease reduction if the ttHit running average is large
// Decrease reduction if the ttHit running average is large (~0 Elo)
if (thisThread->ttHitAverage > 537 * TtHitAverageResolution * TtHitAverageWindow / 1024)
r--;
// Decrease reduction if position is or has been on the PV
// and node is not likely to fail low. (~10 Elo)
// and node is not likely to fail low. (~3 Elo)
if ( ss->ttPv
&& !likelyFailLow)
r -= 2;
@@ -1170,10 +1157,7 @@ moves_loop: // When in check, search starts from here
if (ttCapture)
r++;
// Increase reduction at root if failing high
r += rootNode ? thisThread->failedHighCnt * thisThread->failedHighCnt * moveCount / 512 : 0;
// Increase reduction for cut nodes (~10 Elo)
// Increase reduction for cut nodes (~3 Elo)
if (cutNode)
r += 2;
@@ -1181,23 +1165,11 @@ moves_loop: // When in check, search starts from here
+ (*contHist[0])[movedPiece][to_sq(move)]
+ (*contHist[1])[movedPiece][to_sq(move)]
+ (*contHist[3])[movedPiece][to_sq(move)]
- 4741;
// Decrease/increase reduction by comparing opponent's stat score (~10 Elo)
if (ss->statScore >= -89 && (ss-1)->statScore < -116)
r--;
else if ((ss-1)->statScore >= -112 && ss->statScore < -100)
r++;
- 4923;
// Decrease/increase reduction for moves with a good/bad history (~30 Elo)
// If we are not in check use statScore, but if we are in check we use
// the sum of main history and first continuation history with an offset.
if (ss->inCheck)
r -= (thisThread->mainHistory[us][from_to(move)]
+ (*contHist[0])[movedPiece][to_sq(move)] - 3833) / 16384;
else
r -= ss->statScore / 14790;
if (!ss->inCheck)
r -= ss->statScore / 14721;
}
// In general we want to cap the LMR depth search at newDepth. But if
@@ -1460,7 +1432,7 @@ moves_loop: // When in check, search starts from here
// and addition of two tempos
ss->staticEval = bestValue =
(ss-1)->currentMove != MOVE_NULL ? evaluate(pos)
: -(ss-1)->staticEval + 2 * Tempo;
: -(ss-1)->staticEval;
// Stand pat. Return immediately if static value is at least beta
if (bestValue >= beta)
@@ -1548,7 +1520,7 @@ moves_loop: // When in check, search starts from here
[pos.moved_piece(move)]
[to_sq(move)];
// CounterMove based pruning
// Continuation history based pruning
if ( !captureOrPromotion
&& bestValue > VALUE_TB_LOSS_IN_MAX_PLY
&& (*contHist[0])[pos.moved_piece(move)][to_sq(move)] < CounterMovePruneThreshold