std::memset(ss-7, 0, 10 * sizeof(Stack));
for (int i = 7; i > 0; i--)
- (ss-i)->continuationHistory = &this->continuationHistory[0][NO_PIECE][0]; // Use as a sentinel
+ (ss-i)->continuationHistory = &this->continuationHistory[0][0][NO_PIECE][0]; // Use as a sentinel
ss->pv = pv;
Depth extension, newDepth;
Value bestValue, value, ttValue, eval, maxValue;
bool ttHit, ttPv, inCheck, givesCheck, improving, doLMR, priorCapture;
- bool captureOrPromotion, doFullDepthSearch, moveCountPruning, ttCapture;
+ bool captureOrPromotion, doFullDepthSearch, moveCountPruning, ttCapture, singularLMR;
Piece movedPiece;
- int moveCount, captureCount, quietCount, singularLMR;
+ int moveCount, captureCount, quietCount;
// Step 1. Initialize node
Thread* thisThread = pos.this_thread();
inCheck = pos.checkers();
priorCapture = pos.captured_piece();
Color us = pos.side_to_move();
- moveCount = captureCount = quietCount = singularLMR = ss->moveCount = 0;
+ moveCount = captureCount = quietCount = ss->moveCount = 0;
bestValue = -VALUE_INFINITE;
maxValue = VALUE_INFINITE;
Depth R = (835 + 70 * depth) / 256 + std::min(int(eval - beta) / 185, 3);
ss->currentMove = MOVE_NULL;
- ss->continuationHistory = &thisThread->continuationHistory[0][NO_PIECE][0];
+ ss->continuationHistory = &thisThread->continuationHistory[0][0][NO_PIECE][0];
pos.do_null_move(st);
&& probCutCount < 2 + 2 * cutNode)
if (move != excludedMove && pos.legal(move))
{
+ assert(pos.capture_or_promotion(move));
+ assert(depth >= 5);
+
+ captureOrPromotion = true;
probCutCount++;
ss->currentMove = move;
- ss->continuationHistory = &thisThread->continuationHistory[priorCapture][pos.moved_piece(move)][to_sq(move)];
-
- assert(depth >= 5);
+ ss->continuationHistory = &thisThread->continuationHistory[inCheck]
+ [captureOrPromotion]
+ [pos.moved_piece(move)]
+ [to_sq(move)];
pos.do_move(move, st);
moves_loop: // When in check, search starts from here
const PieceToHistory* contHist[] = { (ss-1)->continuationHistory, (ss-2)->continuationHistory,
- nullptr, (ss-4)->continuationHistory,
- nullptr, (ss-6)->continuationHistory };
+ nullptr , (ss-4)->continuationHistory,
+ nullptr , (ss-6)->continuationHistory };
Move countermove = thisThread->counterMoves[pos.piece_on(prevSq)][prevSq];
countermove,
ss->killers);
- value = bestValue; // Workaround a bogus 'uninitialized' warning under gcc
- moveCountPruning = false;
+ value = bestValue;
+ singularLMR = moveCountPruning = false;
ttCapture = ttMove && pos.capture_or_promotion(ttMove);
// Mark this node as being searched
if (value < singularBeta)
{
extension = 1;
- singularLMR++;
-
- if (value < singularBeta - std::min(4 * depth, 36))
- singularLMR++;
+ singularLMR = true;
}
// Multi-cut pruning
// Update the current move (this must be done after singular extension search)
ss->currentMove = move;
- ss->continuationHistory = &thisThread->continuationHistory[priorCapture][movedPiece][to_sq(move)];
+ ss->continuationHistory = &thisThread->continuationHistory[inCheck]
+ [captureOrPromotion]
+ [movedPiece]
+ [to_sq(move)];
// Step 15. Make the move
pos.do_move(move, st, givesCheck);
r--;
// Decrease reduction if ttMove has been singularly extended
- r -= singularLMR;
+ if (singularLMR)
+ r -= 2;
if (!captureOrPromotion)
{
Move ttMove, move, bestMove;
Depth ttDepth;
Value bestValue, value, ttValue, futilityValue, futilityBase, oldAlpha;
- bool ttHit, pvHit, inCheck, givesCheck, evasionPrunable, priorCapture;
+ bool ttHit, pvHit, inCheck, givesCheck, captureOrPromotion, evasionPrunable;
int moveCount;
if (PvNode)
(ss+1)->ply = ss->ply + 1;
bestMove = MOVE_NONE;
inCheck = pos.checkers();
- priorCapture = pos.captured_piece();
moveCount = 0;
// Check for an immediate draw or maximum ply reached
}
const PieceToHistory* contHist[] = { (ss-1)->continuationHistory, (ss-2)->continuationHistory,
- nullptr, (ss-4)->continuationHistory,
- nullptr, (ss-6)->continuationHistory };
+ nullptr , (ss-4)->continuationHistory,
+ nullptr , (ss-6)->continuationHistory };
// Initialize a MovePicker object for the current position, and prepare
// to search the moves. Because the depth is <= 0 here, only captures,
assert(is_ok(move));
givesCheck = pos.gives_check(move);
+ captureOrPromotion = pos.capture_or_promotion(move);
moveCount++;
}
ss->currentMove = move;
- ss->continuationHistory = &thisThread->continuationHistory[priorCapture][pos.moved_piece(move)][to_sq(move)];
+ ss->continuationHistory = &thisThread->continuationHistory[inCheck]
+ [captureOrPromotion]
+ [pos.moved_piece(move)]
+ [to_sq(move)];
// Make and search the move
pos.do_move(move, st, givesCheck);