if (bestValue >= beta) // Failed high
{
- TT.store(posKey, value_to_tt(bestValue, ss->ply), BOUND_LOWER, depth,
- bestMove, ss->staticEval, ss->evalMargin);
+ TT.store(posKey, value_to_tt(bestValue, ss->ply), BOUND_LOWER, depth, bestMove);
if (!pos.is_capture_or_promotion(bestMove) && !inCheck)
{
else // Failed low or PV search
TT.store(posKey, value_to_tt(bestValue, ss->ply),
PvNode && bestMove != MOVE_NONE ? BOUND_EXACT : BOUND_UPPER,
- depth, bestMove, ss->staticEval, ss->evalMargin);
+ depth, bestMove);
assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);
Key posKey;
Move ttMove, move, bestMove;
Value bestValue, value, ttValue, futilityValue, futilityBase, oldAlpha;
- bool givesCheck, enoughMaterial, evasionPrunable;
+ bool givesCheck, enoughMaterial, evasionPrunable, fromNull;
Depth ttDepth;
// To flag BOUND_EXACT a node with eval above alpha and no available moves
ss->currentMove = bestMove = MOVE_NONE;
ss->ply = (ss-1)->ply + 1;
+ fromNull = (ss-1)->currentMove == MOVE_NULL;
// Check for an instant draw or maximum ply reached
if (pos.is_draw<false, false>() || ss->ply > MAX_PLY)
}
else
{
- ss->staticEval = bestValue = evaluate(pos, ss->evalMargin);
+ if (fromNull)
+ {
+ // Approximated score. Real one is slightly higher due to tempo
+ ss->staticEval = bestValue = -(ss-1)->staticEval;
+ ss->evalMargin = VALUE_ZERO;
+ }
+ else
+ ss->staticEval = bestValue = evaluate(pos, ss->evalMargin);
// Stand pat. Return immediately if static value is at least beta
if (bestValue >= beta)
{
if (!tte)
- TT.store(pos.key(), value_to_tt(bestValue, ss->ply), BOUND_LOWER,
- DEPTH_NONE, MOVE_NONE, ss->staticEval, ss->evalMargin);
+ TT.store(pos.key(), value_to_tt(bestValue, ss->ply), BOUND_LOWER, DEPTH_NONE, MOVE_NONE);
return bestValue;
}
// Futility pruning
if ( !PvNode
&& !InCheck
+ && !fromNull
&& !givesCheck
&& move != ttMove
&& enoughMaterial
}
else // Fail high
{
- TT.store(posKey, value_to_tt(value, ss->ply), BOUND_LOWER,
- ttDepth, move, ss->staticEval, ss->evalMargin);
-
+ TT.store(posKey, value_to_tt(value, ss->ply), BOUND_LOWER, ttDepth, move);
return value;
}
}
TT.store(posKey, value_to_tt(bestValue, ss->ply),
PvNode && bestValue > oldAlpha ? BOUND_EXACT : BOUND_UPPER,
- ttDepth, bestMove, ss->staticEval, ss->evalMargin);
+ ttDepth, bestMove);
assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);
StateInfo state[MAX_PLY_PLUS_2], *st = state;
TTEntry* tte;
int ply = 0;
- Value v, m;
do {
tte = TT.probe(pos.key());
if (!tte || tte->move() != pv[ply]) // Don't overwrite correct entries
- {
- if (pos.in_check())
- v = m = VALUE_NONE;
- else
- v = evaluate(pos, m);
-
- TT.store(pos.key(), VALUE_NONE, BOUND_NONE, DEPTH_NONE, pv[ply], v, m);
- }
+ TT.store(pos.key(), VALUE_NONE, BOUND_NONE, DEPTH_NONE, pv[ply]);
assert(pos.move_is_legal(pv[ply]));
pos.do_move(pv[ply++], *st++);