// Step 6. Razoring
// Maximum depth for razoring
- const Depth RazorDepth = 4 * OnePly;
+ const Depth RazorDepth = 4 * ONE_PLY;
// Dynamic razoring margin based on depth
inline Value razor_margin(Depth d) { return Value(0x200 + 0x10 * int(d)); }
const Value NullMoveMargin = Value(0x200);
// Maximum depth for use of dynamic threat detection when null move fails low
- const Depth ThreatDepth = 5 * OnePly;
+ const Depth ThreatDepth = 5 * ONE_PLY;
// Step 9. Internal iterative deepening
// Minimum depth for use of internal iterative deepening
- const Depth IIDDepth[2] = { 8 * OnePly /* non-PV */, 5 * OnePly /* PV */};
+ const Depth IIDDepth[2] = { 8 * ONE_PLY /* non-PV */, 5 * ONE_PLY /* PV */};
// At Non-PV nodes we do an internal iterative deepening search
// when the static evaluation is bigger then beta - IIDMargin.
Depth PassedPawnExtension[2], PawnEndgameExtension[2], MateThreatExtension[2];
// Minimum depth for use of singular extension
- const Depth SingularExtensionDepth[2] = { 7 * OnePly /* non-PV */, 6 * OnePly /* PV */};
+ const Depth SingularExtensionDepth[2] = { 8 * ONE_PLY /* non-PV */, 6 * ONE_PLY /* PV */};
// If the TT move is at least SingularExtensionMargin better then the
// remaining ones we will extend it.
int32_t FutilityMarginsMatrix[16][64]; // [depth][moveNumber]
int FutilityMoveCountArray[32]; // [depth]
- inline Value futility_margin(Depth d, int mn) { return Value(d < 7 * OnePly ? FutilityMarginsMatrix[Max(d, 1)][Min(mn, 63)] : 2 * VALUE_INFINITE); }
- inline int futility_move_count(Depth d) { return d < 16 * OnePly ? FutilityMoveCountArray[d] : 512; }
+ inline Value futility_margin(Depth d, int mn) { return Value(d < 7 * ONE_PLY ? FutilityMarginsMatrix[Max(d, 1)][Min(mn, 63)] : 2 * VALUE_INFINITE); }
+ inline int futility_move_count(Depth d) { return d < 16 * ONE_PLY ? FutilityMoveCountArray[d] : 512; }
// Step 14. Reduced search
// Common adjustments
// Search depth at iteration 1
- const Depth InitialDepth = OnePly;
+ const Depth InitialDepth = ONE_PLY;
// Easy move margin. An easy move candidate must be at least this much
// better than the second best move.
void init_search() {
- int d; // depth (OnePly == 2)
- int hd; // half depth (OnePly == 1)
+ int d; // depth (ONE_PLY == 2)
+ int hd; // half depth (ONE_PLY == 1)
int mc; // moveCount
// Init reductions array
{
double pvRed = 0.33 + log(double(hd)) * log(double(mc)) / 4.5;
double nonPVRed = 0.33 + log(double(hd)) * log(double(mc)) / 2.25;
- ReductionMatrix[PV][hd][mc] = (int8_t) ( pvRed >= 1.0 ? floor( pvRed * int(OnePly)) : 0);
- ReductionMatrix[NonPV][hd][mc] = (int8_t) (nonPVRed >= 1.0 ? floor(nonPVRed * int(OnePly)) : 0);
+ ReductionMatrix[PV][hd][mc] = (int8_t) ( pvRed >= 1.0 ? floor( pvRed * int(ONE_PLY)) : 0);
+ ReductionMatrix[NonPV][hd][mc] = (int8_t) (nonPVRed >= 1.0 ? floor(nonPVRed * int(ONE_PLY)) : 0);
}
// Init futility margins array
// If we are at the last ply we don't need to do and undo
// the moves, just to count them.
- if (depth <= OnePly)
+ if (depth <= ONE_PLY)
return int(last - mlist);
// Loop through all legal moves
{
m = cur->move;
pos.do_move(m, st, ci, pos.move_is_check(m, ci));
- sum += perft(pos, depth - OnePly);
+ sum += perft(pos, depth - ONE_PLY);
pos.undo_move(m);
}
return sum;
MateThreatExtension[1] = Depth(get_option_value_int("Mate Threat Extension (PV nodes)"));
MateThreatExtension[0] = Depth(get_option_value_int("Mate Threat Extension (non-PV nodes)"));
- MinimumSplitDepth = get_option_value_int("Minimum Split Depth") * OnePly;
+ MinimumSplitDepth = get_option_value_int("Minimum Split Depth") * ONE_PLY;
MaxThreadsPerSplitPoint = get_option_value_int("Maximum Number of Threads per Split Point");
MultiPV = get_option_value_int("MultiPV");
Chess960 = get_option_value_bool("UCI_Chess960");
alpha = *alphaPtr;
beta = *betaPtr;
isCheck = pos.is_check();
- depth = (Iteration - 2) * OnePly + InitialDepth;
+ depth = (Iteration - 2) * ONE_PLY + InitialDepth;
// Step 1. Initialize node (polling is omitted at root)
ss->currentMove = ss->bestMove = MOVE_NONE;
// if the move fails high will be re-searched at full depth
bool doFullDepthSearch = true;
- if ( depth >= 3 * OnePly
+ if ( depth >= 3 * ONE_PLY
&& !dangerous
&& !captureOrPromotion
&& !move_is_castle(move))
ss->reduction = reduction<PV>(depth, i - MultiPV + 2);
if (ss->reduction)
{
- assert(newDepth-ss->reduction >= OnePly);
+ assert(newDepth-ss->reduction >= ONE_PLY);
// Reduced depth non-pv search using alpha as upperbound
value = -search<NonPV>(pos, ss+1, -(alpha+1), -alpha, newDepth-ss->reduction, 1);
// The move failed high, but if reduction is very big we could
// face a false positive, retry with a less aggressive reduction,
// if the move fails high again then go with full depth search.
- if (doFullDepthSearch && ss->reduction > 2 * OnePly)
+ if (doFullDepthSearch && ss->reduction > 2 * ONE_PLY)
{
- assert(newDepth - OnePly >= OnePly);
+ assert(newDepth - ONE_PLY >= ONE_PLY);
- ss->reduction = OnePly;
+ ss->reduction = ONE_PLY;
value = -search<NonPV>(pos, ss+1, -(alpha+1), -alpha, newDepth-ss->reduction, 1);
doFullDepthSearch = (value > alpha);
}
- ss->reduction = Depth(0); // Restore original reduction
+ ss->reduction = DEPTH_ZERO; // Restore original reduction
}
// Step 15. Full depth search
Move movesSearched[256];
EvalInfo ei;
StateInfo st;
- const TTEntry *tte, *ttx;
+ const TTEntry *tte;
Key posKey;
Move ttMove, move, excludedMove, threatMove;
Depth ext, newDepth;
// Step 2. Check for aborted search and immediate draw
if (AbortSearch || ThreadsMgr.thread_should_stop(threadID))
- return Value(0);
+ return VALUE_ZERO;
if (pos.is_draw() || ply >= PLY_MAX - 1)
return VALUE_DRAW;
&& !pos.has_pawn_on_7th(pos.side_to_move()))
{
Value rbeta = beta - razor_margin(depth);
- Value v = qsearch<NonPV>(pos, ss, rbeta-1, rbeta, Depth(0), ply);
+ Value v = qsearch<NonPV>(pos, ss, rbeta-1, rbeta, DEPTH_ZERO, ply);
if (v < rbeta)
// Logically we should return (v + razor_margin(depth)), but
// surprisingly this did slightly weaker in tests.
// NullMoveMargin under beta.
if ( !PvNode
&& !ss->skipNullMove
- && depth > OnePly
+ && depth > ONE_PLY
&& !isCheck
- && refinedValue >= beta - (depth >= 4 * OnePly ? NullMoveMargin : 0)
+ && refinedValue >= beta - (depth >= 4 * ONE_PLY ? NullMoveMargin : 0)
&& !value_is_mate(beta)
&& pos.non_pawn_material(pos.side_to_move()))
{
ss->currentMove = MOVE_NULL;
// Null move dynamic reduction based on depth
- int R = 3 + (depth >= 5 * OnePly ? depth / 8 : 0);
+ int R = 3 + (depth >= 5 * ONE_PLY ? depth / 8 : 0);
// Null move dynamic reduction based on value
if (refinedValue - beta > PawnValueMidgame)
pos.do_null_move(st);
(ss+1)->skipNullMove = true;
- nullValue = depth-R*OnePly < OnePly ? -qsearch<NonPV>(pos, ss+1, -beta, -alpha, Depth(0), ply+1)
- : - search<NonPV>(pos, ss+1, -beta, -alpha, depth-R*OnePly, ply+1);
+ nullValue = depth-R*ONE_PLY < ONE_PLY ? -qsearch<NonPV>(pos, ss+1, -beta, -alpha, DEPTH_ZERO, ply+1)
+ : - search<NonPV>(pos, ss+1, -beta, -alpha, depth-R*ONE_PLY, ply+1);
(ss+1)->skipNullMove = false;
pos.undo_null_move();
if (nullValue >= value_mate_in(PLY_MAX))
nullValue = beta;
- if (depth < 6 * OnePly)
+ if (depth < 6 * ONE_PLY)
return nullValue;
// Do verification search at high depths
ss->skipNullMove = true;
- Value v = search<NonPV>(pos, ss, alpha, beta, depth-R*OnePly, ply);
+ Value v = search<NonPV>(pos, ss, alpha, beta, depth-R*ONE_PLY, ply);
ss->skipNullMove = false;
if (v >= beta)
&& ttMove == MOVE_NONE
&& (PvNode || (!isCheck && ss->eval >= beta - IIDMargin)))
{
- Depth d = (PvNode ? depth - 2 * OnePly : depth / 2);
+ Depth d = (PvNode ? depth - 2 * ONE_PLY : depth / 2);
ss->skipNullMove = true;
search<PvNode>(pos, ss, alpha, beta, d, ply);
&& tte->move()
&& !excludedMove // Do not allow recursive singular extension search
&& is_lower_bound(tte->type())
- && tte->depth() >= depth - 3 * OnePly;
+ && tte->depth() >= depth - 3 * ONE_PLY;
// Step 10. Loop through moves
// Loop through all legal moves until no moves remain or a beta cutoff occurs
// lower then ttValue minus a margin then we extend ttMove.
if ( singularExtensionNode
&& move == tte->move()
- && ext < OnePly)
+ && ext < ONE_PLY)
{
- // Avoid to do an expensive singular extension search on nodes where
- // such search have already been done in the past, so assume the last
- // singular extension search result is still valid.
- if ( !PvNode
- && depth < SingularExtensionDepth[PvNode] + 5 * OnePly
- && (ttx = TT.retrieve(pos.get_exclusion_key())) != NULL)
- {
- if (is_upper_bound(ttx->type()))
- ext = OnePly;
-
- singularExtensionNode = false;
- }
-
Value ttValue = value_from_tt(tte->value(), ply);
- if (singularExtensionNode && abs(ttValue) < VALUE_KNOWN_WIN)
+ if (abs(ttValue) < VALUE_KNOWN_WIN)
{
Value b = ttValue - SingularExtensionMargin;
ss->excludedMove = move;
ss->excludedMove = MOVE_NONE;
ss->bestMove = MOVE_NONE;
if (v < b)
- ext = OnePly;
+ ext = ONE_PLY;
}
}
- newDepth = depth - OnePly + ext;
+ newDepth = depth - ONE_PLY + ext;
// Update current move (this must be done after singular extension search)
movesSearched[moveCount++] = ss->currentMove = move;
continue;
// Value based pruning
- // We illogically ignore reduction condition depth >= 3*OnePly for predicted depth,
+ // We illogically ignore reduction condition depth >= 3*ONE_PLY for predicted depth,
// but fixing this made program slightly weaker.
Depth predictedDepth = newDepth - reduction<NonPV>(depth, moveCount);
futilityValueScaled = ss->eval + futility_margin(predictedDepth, moveCount)
// Step extra. pv search (only in PV nodes)
// The first move in list is the expected PV
if (PvNode && moveCount == 1)
- value = newDepth < OnePly ? -qsearch<PV>(pos, ss+1, -beta, -alpha, Depth(0), ply+1)
- : - search<PV>(pos, ss+1, -beta, -alpha, newDepth, ply+1);
+ value = newDepth < ONE_PLY ? -qsearch<PV>(pos, ss+1, -beta, -alpha, DEPTH_ZERO, ply+1)
+
: - search<PV>(pos, ss+1, -beta, -alpha, newDepth, ply+1);
else
{
// Step 14. Reduced depth search
// If the move fails high will be re-searched at full depth.
bool doFullDepthSearch = true;
- if ( depth >= 3 * OnePly
+ if ( depth >= 3 * ONE_PLY
&& !captureOrPromotion
&& !dangerous
&& !move_is_castle(move)
if (ss->reduction)
{
Depth d = newDepth - ss->reduction;
- value = d < OnePly ? -qsearch<NonPV>(pos, ss+1, -(alpha+1), -alpha, Depth(0), ply+1)
- : - search<NonPV>(pos, ss+1, -(alpha+1), -alpha, d, ply+1);
+ value = d < ONE_PLY ? -qsearch<NonPV>(pos, ss+1, -(alpha+1), -alpha, DEPTH_ZERO, ply+1)
+ : - search<NonPV>(pos, ss+1, -(alpha+1), -alpha, d, ply+1);
doFullDepthSearch = (value > alpha);
}
// The move failed high, but if reduction is very big we could
// face a false positive, retry with a less aggressive reduction,
// if the move fails high again then go with full depth search.
- if (doFullDepthSearch && ss->reduction > 2 * OnePly)
+ if (doFullDepthSearch && ss->reduction > 2 * ONE_PLY)
{
- assert(newDepth - OnePly >= OnePly);
+ assert(newDepth - ONE_PLY >= ONE_PLY);
- ss->reduction = OnePly;
+ ss->reduction = ONE_PLY;
value = -search<NonPV>(pos, ss+1, -(alpha+1), -alpha, newDepth-ss->reduction, ply+1);
doFullDepthSearch = (value > alpha);
}
- ss->reduction = Depth(0); // Restore original reduction
+ ss->reduction = DEPTH_ZERO; // Restore original reduction
}
// Step 15. Full depth search
if (doFullDepthSearch)
{
- value = newDepth < OnePly ? -qsearch<NonPV>(pos, ss+1, -(alpha+1), -alpha, Depth(0), ply+1)
- : - search<NonPV>(pos, ss+1, -(alpha+1), -alpha, newDepth, ply+1);
+ value = newDepth < ONE_PLY ? -qsearch<NonPV>(pos, ss+1, -(alpha+1), -alpha, DEPTH_ZERO, ply+1)
+ : - search<NonPV>(pos, ss+1, -(alpha+1), -alpha, newDepth, ply+1);
// Step extra. pv search (only in PV nodes)
// Search only for possible new PV nodes, if instead value >= beta then
// parent node fails low with value <= alpha and tries another move.
if (PvNode && value > alpha && value < beta)
- value = newDepth < OnePly ? -qsearch<PV>(pos, ss+1, -beta, -alpha, Depth(0), ply+1)
- : - search<PV>(pos, ss+1, -beta, -alpha, newDepth, ply+1);
+ value = newDepth < ONE_PLY ? -qsearch<PV>(pos, ss+1, -beta, -alpha, DEPTH_ZERO, ply+1)
+
: - search<PV>(pos, ss+1, -beta, -alpha, newDepth, ply+1);
}
}
// qsearch() is the quiescence search function, which is called by the main
// search function when the remaining depth is zero (or, to be more precise,
- // less than OnePly).
+ // less than ONE_PLY).
template <NodeType PvNode>
Value qsearch(Position& pos, SearchStack* ss, Value alpha, Value beta, Depth depth, int ply) {
alpha = bestValue;
// If we are near beta then try to get a cutoff pushing checks a bit further
- deepChecks = (depth == -OnePly && bestValue >= beta - PawnValueMidgame / 8);
+ deepChecks = (depth == -ONE_PLY && bestValue >= beta - PawnValueMidgame / 8);
// Futility pruning parameters, not needed when in check
futilityBase = bestValue + FutilityMarginQS + ei.kingDanger[pos.side_to_move()];
// Initialize a MovePicker object for the current position, and prepare
// to search the moves. Because the depth is <= 0 here, only captures,
- // queen promotions and checks (only if depth == 0 or depth == -OnePly
+ // queen promotions and checks (only if depth == 0 or depth == -ONE_PLY
// and we are near beta) will be generated.
- MovePicker mp = MovePicker(pos, ttMove, deepChecks ? Depth(0) : depth, H);
+ MovePicker mp = MovePicker(pos, ttMove, deepChecks ? DEPTH_ZERO : depth, H);
CheckInfo ci(pos);
// Loop through the moves until no moves remain or a beta cutoff occurs
{
futilityValue = futilityBase
+ pos.endgame_value_of_piece_on(move_to(move))
- + (move_is_ep(move) ? PawnValueEndgame : Value(0));
+ + (move_is_ep(move) ? PawnValueEndgame : VALUE_ZERO);
if (futilityValue < alpha)
{
// Make and search the move
pos.do_move(move, st, ci, moveIsCheck);
- value = -qsearch<PvNode>(pos, ss+1, -beta, -alpha, depth-OnePly, ply+1);
+ value = -qsearch<PvNode>(pos, ss+1, -beta, -alpha, depth-ONE_PLY, ply+1);
pos.undo_move(move);
assert(value > -VALUE_INFINITE && value < VALUE_INFINITE);
return value_mated_in(ply);
// Update transposition table
- Depth d = (depth == Depth(0) ? Depth(0) : Depth(-1));
+ Depth d = (depth == DEPTH_ZERO ? DEPTH_ZERO : DEPTH_ZERO - ONE_PLY);
ValueType vt = (bestValue <= oldAlpha ? VALUE_TYPE_UPPER : bestValue >= beta ? VALUE_TYPE_LOWER : VALUE_TYPE_EXACT);
TT.store(pos.get_key(), value_to_tt(bestValue, ply), vt, d, ss->bestMove, ss->eval, ei.kingDanger[pos.side_to_move()]);
// Step 11. Decide the new search depth
ext = extension<PvNode>(pos, move, captureOrPromotion, moveIsCheck, false, sp->mateThreat, &dangerous);
- newDepth = sp->depth - OnePly + ext;
+ newDepth = sp->depth - ONE_PLY + ext;
// Update current move
ss->currentMove = move;
{
Value localAlpha = sp->alpha;
Depth d = newDepth - ss->reduction;
- value = d < OnePly ? -qsearch<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, Depth(0), sp->ply+1)
- : - search<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, d, sp->ply+1);
+ value = d < ONE_PLY ? -qsearch<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, DEPTH_ZERO, sp->ply+1)
+ : - search<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, d, sp->ply+1);
doFullDepthSearch = (value > localAlpha);
}
// The move failed high, but if reduction is very big we could
// face a false positive, retry with a less aggressive reduction,
// if the move fails high again then go with full depth search.
- if (doFullDepthSearch && ss->reduction > 2 * OnePly)
+ if (doFullDepthSearch && ss->reduction > 2 * ONE_PLY)
{
- assert(newDepth - OnePly >= OnePly);
+ assert(newDepth - ONE_PLY >= ONE_PLY);
- ss->reduction = OnePly;
+ ss->reduction = ONE_PLY;
Value localAlpha = sp->alpha;
value = -search<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, newDepth-ss->reduction, sp->ply+1);
doFullDepthSearch = (value > localAlpha);
}
- ss->reduction = Depth(0); // Restore original reduction
+ ss->reduction = DEPTH_ZERO; // Restore original reduction
}
// Step 15. Full depth search
if (doFullDepthSearch)
{
Value localAlpha = sp->alpha;
- value = newDepth < OnePly ? -qsearch<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, Depth(0), sp->ply+1)
- : - search<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, newDepth, sp->ply+1);
+ value = newDepth < ONE_PLY ? -qsearch<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, DEPTH_ZERO, sp->ply+1)
+ : - search<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, newDepth, sp->ply+1);
// Step extra. pv search (only in PV nodes)
// Search only for possible new PV nodes, if instead value >= beta then
// parent node fails low with value <= alpha and tries another move.
if (PvNode && value > localAlpha && value < sp->beta)
- value = newDepth < OnePly ? -qsearch<PV>(pos, ss+1, -sp->beta, -sp->alpha, Depth(0), sp->ply+1)
- : - search<PV>(pos, ss+1, -sp->beta, -sp->alpha, newDepth, sp->ply+1);
+ value = newDepth < ONE_PLY ? -qsearch<PV>(pos, ss+1, -sp->beta, -sp->alpha, DEPTH_ZERO, sp->ply+1)
+
: - search<PV>(pos, ss+1, -sp->beta, -sp->alpha, newDepth, sp->ply+1);
}
// Step 16. Undo move
assert(m != MOVE_NONE);
- Depth result = Depth(0);
+ Depth result = DEPTH_ZERO;
*dangerous = moveIsCheck | singleEvasion | mateThreat;
if (*dangerous)
if ( captureOrPromotion
&& pos.type_of_piece_on(move_to(m)) != PAWN
&& ( pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK)
- - pos.midgame_value_of_piece_on(move_to(m)) == Value(0))
+ - pos.midgame_value_of_piece_on(move_to(m)) == VALUE_ZERO)
&& !move_is_promotion(m)
&& !move_is_ep(m))
{
&& pos.type_of_piece_on(move_to(m)) != PAWN
&& pos.see_sign(m) >= 0)
{
- result += OnePly/2;
+ result += ONE_PLY / 2;
*dangerous = true;
}
- return Min(result, OnePly);
+ return Min(result, ONE_PLY);
}
std::stringstream s;
- if (abs(v) < VALUE_MATE - PLY_MAX * OnePly)
+ if (abs(v) < VALUE_MATE - PLY_MAX * ONE_PLY)
s << "cp " << int(v) * 100 / int(PawnValueMidgame); // Scale to pawn = 100
else
s << "mate " << (v > 0 ? (VALUE_MATE - v + 1) / 2 : -(VALUE_MATE + v) / 2 );
{
ss->excludedMove = MOVE_NONE;
ss->skipNullMove = false;
- ss->reduction = Depth(0);
+ ss->reduction = DEPTH_ZERO;
if (i < 3)
ss->killers[0] = ss->killers[1] = ss->mateKiller = MOVE_NONE;
assert(*bestValue <= *alpha);
assert(*alpha < beta);
assert(beta <= VALUE_INFINITE);
- assert(depth > Depth(0));
+ assert(depth > DEPTH_ZERO);
assert(p.thread() >= 0 && p.thread() < ActiveThreads);
assert(ActiveThreads > 1);
pos.do_move(cur->move, st);
ss[0].currentMove = cur->move;
moves[count].move = cur->move;
- moves[count].score = -qsearch<PV>(pos, ss+1, -VALUE_INFINITE, VALUE_INFINITE, Depth(0), 1);
+ moves[count].score = -qsearch<PV>(pos, ss+1, -VALUE_INFINITE, VALUE_INFINITE, DEPTH_ZERO, 1);
moves[count].pv[0] = cur->move;
moves[count].pv[1] = MOVE_NONE;
pos.undo_move(cur->move);
projects / stockfish / blobdiff