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stockfish
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Retire futility_move_count() 

And remove (bestValue < beta) condition from
moves loop.

No functional change.
sf_3_base
Marco Costalba 2012-10-05 15:00:35 +02:00
parent d471c49700
commit 1ac417edb8
1 changed files with 19 additions and 20 deletions
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39
src/search.cpp
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@ -78,11 +78,6 @@ namespace {
: 2 * VALUE_INFINITE;
}
inline int futility_move_count(Depth d) {
return d < 16 * ONE_PLY ? FutilityMoveCounts[d] : MAX_MOVES;
}
// Reduction lookup tables (initialized at startup) and their access function
int8_t Reductions[2][64][64]; // [pv][depth][moveNumber]
@ -640,10 +635,10 @@ namespace {
&& !ss->skipNullMove
&& depth < 4 * ONE_PLY
&& !inCheck
&& refinedValue - futility_margin(depth, 0) >= beta
&& refinedValue - FutilityMargins[depth][0] >= beta
&& abs(beta) < VALUE_MATE_IN_MAX_PLY
&& pos.non_pawn_material(pos.side_to_move()))
return refinedValue - futility_margin(depth, 0);
return refinedValue - FutilityMargins[depth][0];
// Step 8. Null move search with verification search (is omitted in PV nodes)
if ( !PvNode
@ -768,7 +763,7 @@ split_point_start: // At split points actual search starts from here
// Step 11. Loop through moves
// Loop through all pseudo-legal moves until no moves remain or a beta cutoff occurs
while (bestValue < beta && (move = mp.next_move<SpNode>()) != MOVE_NONE)
while ((move = mp.next_move<SpNode>()) != MOVE_NONE)
{
assert(is_ok(move));
@ -849,7 +844,8 @@ split_point_start: // At split points actual search starts from here
&& (bestValue > VALUE_MATED_IN_MAX_PLY || bestValue == -VALUE_INFINITE))
{
// Move count based pruning
if ( moveCount >= futility_move_count(depth)
if ( depth < 16 * ONE_PLY
&& moveCount >= FutilityMoveCounts[depth]
&& (!threatMove || !connected_threat(pos, move, threatMove)))
{
if (SpNode)
@ -981,23 +977,23 @@ split_point_start: // At split points actual search starts from here
if (value > bestValue)
{
bestValue = value;
if (SpNode) sp->bestValue = value;
if (value > alpha)
{
bestMove = move;
if (SpNode) sp->bestMove = move;
if (PvNode && value < beta)
alpha = bestValue; // Update alpha here! Always alpha < beta
}
if (SpNode)
{
sp->bestValue = bestValue;
sp->bestMove = bestMove;
sp->alpha = alpha;
if (bestValue >= beta)
sp->cutoff = true;
{
alpha = value; // Update alpha here! Always alpha < beta
if (SpNode) sp->alpha = alpha;
}
else // Fail high
{
if (SpNode) sp->cutoff = true;
break;
}
}
}
@ -1006,8 +1002,11 @@ split_point_start: // At split points actual search starts from here
&& depth >= Threads.min_split_depth()
&& bestValue < beta
&& Threads.available_slave_exists(thisThread))
{
bestValue = Threads.split<FakeSplit>(pos, ss, alpha, beta, bestValue, &bestMove,
depth, threatMove, moveCount, mp, NT);
break;
}
}
if (SpNode)