////
#include <cassert>
+#include <cstring>
#include <fstream>
#include <iostream>
#include <sstream>
struct IterationInfoType {
- IterationInfoType(Value v = Value(0), Value sv = Value(0), bool fh = false, bool fl = false)
- : value(v), speculatedValue(sv), failHigh(fh), failLow(fl) {}
+ IterationInfoType(Value v = Value(0), Value sv = Value(0))
+ : value(v), speculatedValue(sv) {}
Value value, speculatedValue;
- bool failHigh, failLow;
};
};
- /// Constants and variables
+ /// Constants and variables initialized from UCI options
// Minimum number of full depth (i.e. non-reduced) moves at PV and non-PV
- // nodes:
- int LMRPVMoves = 15;
- int LMRNonPVMoves = 4;
+ // nodes
+ int LMRPVMoves, LMRNonPVMoves;
- // Depth limit for use of dynamic threat detection:
- Depth ThreatDepth = 5*OnePly;
+ // Depth limit for use of dynamic threat detection
+ Depth ThreatDepth;
- // Depth limit for selective search:
- Depth SelectiveDepth = 7*OnePly;
+ // Depth limit for selective search
+ const Depth SelectiveDepth = 7*OnePly;
// Use internal iterative deepening?
const bool UseIIDAtPVNodes = true;
const bool PruneBlockingMoves = false;
// Use futility pruning?
- bool UseQSearchFutilityPruning = true;
- bool UseFutilityPruning = true;
+ bool UseQSearchFutilityPruning, UseFutilityPruning;
// Margins for futility pruning in the quiescence search, and at frontier
// and near frontier nodes
- Value FutilityMarginQS = Value(0x80);
- Value FutilityMargins[6] = { Value(0x100), Value(0x200), Value(0x250),
- Value(0x2A0), Value(0x340), Value(0x3A0) };
+ const Value FutilityMarginQS = Value(0x80);
- // Razoring
- const bool RazorAtDepthOne = false;
- Depth RazorDepth = 4*OnePly;
- Value RazorMargin = Value(0x300);
+ // Remaining depth: 1 ply 1.5 ply 2 ply 2.5 ply 3 ply 3.5 ply
+ const Value FutilityMargins[12] = { Value(0x100), Value(0x120), Value(0x200), Value(0x220), Value(0x250), Value(0x270),
+ // 4 ply 4.5 ply 5 ply 5.5 ply 6 ply 6.5 ply
+ Value(0x2A0), Value(0x2C0), Value(0x340), Value(0x360), Value(0x3A0), Value(0x3C0) };
+ // Razoring
+ const Depth RazorDepth = 4*OnePly;
+
+ // Remaining depth: 1 ply 1.5 ply 2 ply 2.5 ply 3 ply 3.5 ply
+ const Value RazorMargins[6] = { Value(0x180), Value(0x300), Value(0x300), Value(0x3C0), Value(0x3C0), Value(0x3C0) };
+
+ // Remaining depth: 1 ply 1.5 ply 2 ply 2.5 ply 3 ply 3.5 ply
+ const Value RazorApprMargins[6] = { Value(0x520), Value(0x300), Value(0x300), Value(0x300), Value(0x300), Value(0x300) };
// Last seconds noise filtering (LSN)
- bool UseLSNFiltering = false;
+ bool UseLSNFiltering;
bool looseOnTime = false;
- int LSNTime = 4 * 1000; // In milliseconds
- Value LSNValue = Value(0x200);
+ int LSNTime; // In milliseconds
+ Value LSNValue;
- // Extensions. Array index 0 is used at non-PV nodes, index 1 at PV nodes.
- Depth CheckExtension[2] = {OnePly, OnePly};
- Depth SingleReplyExtension[2] = {OnePly / 2, OnePly / 2};
- Depth PawnPushTo7thExtension[2] = {OnePly / 2, OnePly / 2};
- Depth PassedPawnExtension[2] = {Depth(0), Depth(0)};
- Depth PawnEndgameExtension[2] = {OnePly, OnePly};
- Depth MateThreatExtension[2] = {Depth(0), Depth(0)};
+ // Extensions. Array index 0 is used at non-PV nodes, index 1 at PV nodes.
+ Depth CheckExtension[2], SingleReplyExtension[2], PawnPushTo7thExtension[2];
+ Depth PassedPawnExtension[2], PawnEndgameExtension[2], MateThreatExtension[2];
// Search depth at iteration 1
const Depth InitialDepth = OnePly /*+ OnePly/2*/;
int BestMoveChangesByIteration[PLY_MAX_PLUS_2];
// MultiPV mode
- int MultiPV = 1;
+ int MultiPV;
// Time managment variables
int SearchStartTime;
int ExactMaxTime;
// Show current line?
- bool ShowCurrentLine = false;
+ bool ShowCurrentLine;
// Log file
- bool UseLogFile = false;
+ bool UseLogFile;
std::ofstream LogFile;
// MP related variables
- Depth MinimumSplitDepth = 4*OnePly;
- int MaxThreadsPerSplitPoint = 4;
+ Depth MinimumSplitDepth;
+ int MaxThreadsPerSplitPoint;
Thread Threads[THREAD_MAX];
Lock MPLock;
bool AllThreadsShouldExit = false;
////
// The main transposition table
-TranspositionTable TT = TranspositionTable(TTDefaultSize);
+TranspositionTable TT;
// Number of active threads:
LMRPVMoves = get_option_value_int("Full Depth Moves (PV nodes)") + 1;
LMRNonPVMoves = get_option_value_int("Full Depth Moves (non-PV nodes)") + 1;
ThreatDepth = get_option_value_int("Threat Depth") * OnePly;
- SelectiveDepth = get_option_value_int("Selective Plies") * OnePly;
Chess960 = get_option_value_bool("UCI_Chess960");
ShowCurrentLine = get_option_value_bool("UCI_ShowCurrLine");
UseQSearchFutilityPruning = get_option_value_bool("Futility Pruning (Quiescence Search)");
UseFutilityPruning = get_option_value_bool("Futility Pruning (Main Search)");
- FutilityMarginQS = value_from_centipawns(get_option_value_int("Futility Margin (Quiescence Search)"));
- int fmScale = get_option_value_int("Futility Margin Scale Factor (Main Search)");
- for (int i = 0; i < 6; i++)
- FutilityMargins[i] = (FutilityMargins[i] * fmScale) / 100;
-
- RazorDepth = (get_option_value_int("Maximum Razoring Depth") + 1) * OnePly;
- RazorMargin = value_from_centipawns(get_option_value_int("Razoring Margin"));
-
UseLSNFiltering = get_option_value_bool("LSN filtering");
LSNTime = get_option_value_int("LSN Time Margin (sec)") * 1000;
LSNValue = value_from_centipawns(get_option_value_int("LSN Value Margin"));
}
else if (value <= alpha)
{
+ assert(value == alpha);
assert(delta < 0);
fLow = true;
speculatedValue = value;
speculatedValue = Min(Max(speculatedValue, -VALUE_INFINITE), VALUE_INFINITE);
- IterationInfo[Iteration] = IterationInfoType(value, speculatedValue, fHigh, fLow);
+ IterationInfo[Iteration] = IterationInfoType(value, speculatedValue);
// Erase the easy move if it differs from the new best move
if (ss[0].pv[0] != EasyMove)
{
if (alpha >= beta)
{
+ // We failed high, invalidate and skip next moves, leave node-counters
+ // and beta-counters as they are and quickly return, we will try to do
+ // a research at the next iteration with a bigger aspiration window.
rml.set_move_score(i, -VALUE_INFINITE);
- continue; // Leave node-counters and beta-counters as they are
+ continue;
}
int64_t nodes;
Move move;
rml.set_move_score(i, -VALUE_INFINITE);
else
{
- // New best move!
+ // PV move or new best move!
// Update PV
rml.set_move_score(i, value);
// Transposition table lookup. At PV nodes, we don't use the TT for
// pruning, but only for move ordering.
- const TTEntry* tte = TT.retrieve(pos);
+ const TTEntry* tte = TT.retrieve(pos.get_key());
Move ttMove = (tte ? tte->move() : MOVE_NONE);
// Go with internal iterative deepening if we don't have a TT move
return bestValue;
if (bestValue <= oldAlpha)
- TT.store(pos, value_to_tt(bestValue, ply), depth, MOVE_NONE, VALUE_TYPE_UPPER);
+ TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_UPPER, depth, MOVE_NONE);
else if (bestValue >= beta)
{
update_history(pos, m, depth, movesSearched, moveCount);
update_killers(m, ss[ply]);
}
- TT.store(pos, value_to_tt(bestValue, ply), depth, m, VALUE_TYPE_LOWER);
+ TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_LOWER, depth, m);
}
else
- TT.store(pos, value_to_tt(bestValue, ply), depth, ss[ply].pv[ply], VALUE_TYPE_EXACT);
+ TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_EXACT, depth, ss[ply].pv[ply]);
return bestValue;
}
return beta - 1;
// Transposition table lookup
- const TTEntry* tte = TT.retrieve(pos);
+ const TTEntry* tte = TT.retrieve(pos.get_key());
Move ttMove = (tte ? tte->move() : MOVE_NONE);
if (tte && ok_to_use_TT(tte, depth, beta, ply))
}
// Null move search not allowed, try razoring
else if ( !value_is_mate(beta)
- && approximateEval < beta - RazorMargin
&& depth < RazorDepth
- && (RazorAtDepthOne || depth > OnePly)
+ && approximateEval < beta - RazorApprMargins[int(depth) - 2]
+ && ss[ply - 1].currentMove != MOVE_NULL
&& ttMove == MOVE_NONE
&& !pos.has_pawn_on_7th(pos.side_to_move()))
{
Value v = qsearch(pos, ss, beta-1, beta, Depth(0), ply, threadID);
- if ( (v < beta - RazorMargin - RazorMargin / 4)
- || (depth <= 2*OnePly && v < beta - RazorMargin)
- || (depth <= OnePly && v < beta - RazorMargin / 2))
- return v;
+ if (v < beta - RazorMargins[int(depth) - 2])
+ return v;
}
// Go with internal iterative deepening if we don't have a TT move
continue;
// Value based pruning
- if (depth < 7 * OnePly && approximateEval < beta)
+ if (approximateEval < beta)
{
if (futilityValue == VALUE_NONE)
futilityValue = evaluate(pos, ei, threadID)
- + FutilityMargins[int(depth)/2 - 1]
- + 32 * (depth & 1);
+ + FutilityMargins[int(depth) - 2];
if (futilityValue < beta)
{
return bestValue;
if (bestValue < beta)
- TT.store(pos, value_to_tt(bestValue, ply), depth, MOVE_NONE, VALUE_TYPE_UPPER);
+ TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_UPPER, depth, MOVE_NONE);
else
{
BetaCounter.add(pos.side_to_move(), depth, threadID);
update_history(pos, m, depth, movesSearched, moveCount);
update_killers(m, ss[ply]);
}
- TT.store(pos, value_to_tt(bestValue, ply), depth, m, VALUE_TYPE_LOWER);
+ TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_LOWER, depth, m);
}
assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);
bool pvNode = (beta - alpha != 1);
if (!pvNode)
{
- tte = TT.retrieve(pos);
+ tte = TT.retrieve(pos.get_key());
if (tte && ok_to_use_TT(tte, depth, beta, ply))
{
assert(tte->type() != VALUE_TYPE_EVAL);
return value_from_tt(tte->value(), ply);
}
}
+ Move ttMove = (tte ? tte->move() : MOVE_NONE);
// Evaluate the position statically
EvalInfo ei;
{
// Store the score to avoid a future costly evaluation() call
if (!isCheck && !tte && ei.futilityMargin == 0)
- TT.store(pos, value_to_tt(bestValue, ply), Depth(-127*OnePly), MOVE_NONE, VALUE_TYPE_EVAL);
+ TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_EVAL, Depth(-127*OnePly), MOVE_NONE);
return bestValue;
}
// 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) will be generated.
- MovePicker mp = MovePicker(pos, pvNode, MOVE_NONE, EmptySearchStack, depth);
+ MovePicker mp = MovePicker(pos, pvNode, ttMove, EmptySearchStack, depth);
Move move;
int moveCount = 0;
Bitboard dcCandidates = mp.discovered_check_candidates();
assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);
// Update transposition table
+ Move m = ss[ply].pv[ply];
if (!pvNode)
{
Depth d = (depth == Depth(0) ? Depth(0) : Depth(-1));
if (bestValue < beta)
- TT.store(pos, value_to_tt(bestValue, ply), d, MOVE_NONE, VALUE_TYPE_UPPER);
+ TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_UPPER, d, MOVE_NONE);
else
- TT.store(pos, value_to_tt(bestValue, ply), d, MOVE_NONE, VALUE_TYPE_LOWER);
+ TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_LOWER, d, m);
}
// Update killers only for good check moves
- Move m = ss[ply].currentMove;
if (alpha >= beta && ok_to_history(pos, m)) // Only non capture moves are considered
- {
- // Wrong to update history when depth is <= 0
update_killers(m, ss[ply]);
- }
+
return bestValue;
}
// Constructor
RootMove::RootMove() {
- nodes = cumulativeNodes = 0ULL;
+ nodes = cumulativeNodes = ourBeta = theirBeta = 0ULL;
}
// RootMove::operator<() is the comparison function used when
for (int k = 0; !includeMove && searchMoves[k] != MOVE_NONE; k++)
includeMove = (searchMoves[k] == mlist[i].move);
- if (includeMove)
- {
- // Find a quick score for the move
- StateInfo st;
- SearchStack ss[PLY_MAX_PLUS_2];
-
- moves[count].move = mlist[i].move;
- moves[count].nodes = 0ULL;
- pos.do_move(moves[count].move, st);
- moves[count].score = -qsearch(pos, ss, -VALUE_INFINITE, VALUE_INFINITE,
- Depth(0), 1, 0);
- pos.undo_move(moves[count].move);
- moves[count].pv[0] = moves[i].move;
- moves[count].pv[1] = MOVE_NONE; // FIXME
- count++;
- }
+ if (!includeMove)
+ continue;
+
+ // Find a quick score for the move
+ StateInfo st;
+ SearchStack ss[PLY_MAX_PLUS_2];
+
+ moves[count].move = mlist[i].move;
+ pos.do_move(moves[count].move, st);
+ moves[count].score = -qsearch(pos, ss, -VALUE_INFINITE, VALUE_INFINITE, Depth(0), 1, 0);
+ pos.undo_move(moves[count].move);
+ moves[count].pv[0] = moves[count].move;
+ moves[count].pv[1] = MOVE_NONE; // FIXME
+ count++;
}
sort();
}