#include <sstream>
#include "evaluate.h"
+#include "misc.h"
#include "movegen.h"
#include "movepick.h"
-#include "rkiss.h"
#include "search.h"
#include "timeman.h"
#include "thread.h"
volatile SignalsType Signals;
LimitsType Limits;
- std::vector<RootMove> RootMoves;
+ RootMoveVector RootMoves;
Position RootPos;
Time::point SearchTime;
StateStackPtr SetupStates;
TimeMgr.init(Limits, RootPos.game_ply(), RootPos.side_to_move());
- int cf = Options["Contempt"] * PawnValueEg / 100; // From centipawns
- DrawValue[ RootPos.side_to_move()] = VALUE_DRAW - Value(cf);
- DrawValue[~RootPos.side_to_move()] = VALUE_DRAW + Value(cf);
+ int contempt = Options["Contempt"] * PawnValueEg / 100; // From centipawns
+ DrawValue[ RootPos.side_to_move()] = VALUE_DRAW - Value(contempt);
+ DrawValue[~RootPos.side_to_move()] = VALUE_DRAW + Value(contempt);
TB::Hits = 0;
TB::RootInTB = false;
TB::Cardinality = Options["SyzygyProbeLimit"];
// Skip TB probing when no TB found: !TBLargest -> !TB::Cardinality
- if (TB::Cardinality > TB::TBLargest)
+ if (TB::Cardinality > TB::MaxCardinality)
{
- TB::Cardinality = TB::TBLargest;
+ TB::Cardinality = TB::MaxCardinality;
TB::ProbeDepth = DEPTH_ZERO;
}
{
// If the current root position is in the tablebases then RootMoves
// contains only moves that preserve the draw or win.
- TB::RootInTB = Tablebases::root_probe(RootPos, TB::Score);
+ TB::RootInTB = Tablebases::root_probe(RootPos, RootMoves, TB::Score);
if (TB::RootInTB)
TB::Cardinality = 0; // Do not probe tablebases during the search
else // If DTZ tables are missing, use WDL tables as a fallback
{
// Filter out moves that do not preserve a draw or win
- TB::RootInTB = Tablebases::root_probe_wdl(RootPos, TB::Score);
+ TB::RootInTB = Tablebases::root_probe_wdl(RootPos, RootMoves, TB::Score);
// Only probe during search if winning
if (TB::Score <= VALUE_DRAW)
// Save the last iteration's scores before first PV line is searched and
// all the move scores except the (new) PV are set to -VALUE_INFINITE.
for (size_t i = 0; i < RootMoves.size(); ++i)
- RootMoves[i].prevScore = RootMoves[i].score;
+ RootMoves[i].previousScore = RootMoves[i].score;
// MultiPV loop. We perform a full root search for each PV line
for (PVIdx = 0; PVIdx < std::min(multiPV, RootMoves.size()) && !Signals.stop; ++PVIdx)
if (depth >= 5 * ONE_PLY)
{
delta = Value(16);
- alpha = std::max(RootMoves[PVIdx].prevScore - delta,-VALUE_INFINITE);
- beta = std::min(RootMoves[PVIdx].prevScore + delta, VALUE_INFINITE);
+ alpha = std::max(RootMoves[PVIdx].previousScore - delta,-VALUE_INFINITE);
+ beta = std::min(RootMoves[PVIdx].previousScore + delta, VALUE_INFINITE);
}
// Start with a small aspiration window and, in the case of a fail
SplitPoint* splitPoint;
Key posKey;
Move ttMove, move, excludedMove, bestMove;
- Depth ext, newDepth, predictedDepth;
+ Depth extension, newDepth, predictedDepth;
Value bestValue, value, ttValue, eval, nullValue, futilityValue;
bool inCheck, givesCheck, singularExtensionNode, improving;
bool captureOrPromotion, dangerous, doFullDepthSearch;
assert(0 <= ss->ply && ss->ply < MAX_PLY);
ss->currentMove = ss->ttMove = (ss+1)->excludedMove = bestMove = MOVE_NONE;
- (ss+1)->skipNullMove = false; (ss+1)->reduction = DEPTH_ZERO;
+ (ss+1)->skipEarlyPruning = false; (ss+1)->reduction = DEPTH_ZERO;
(ss+2)->killers[0] = (ss+2)->killers[1] = MOVE_NONE;
// Step 4. Transposition table lookup
TT.store(posKey, VALUE_NONE, BOUND_NONE, DEPTH_NONE, MOVE_NONE, ss->staticEval);
}
+ if (ss->skipEarlyPruning)
+ goto moves_loop;
+
if ( !pos.captured_piece_type()
&& ss->staticEval != VALUE_NONE
&& (ss-1)->staticEval != VALUE_NONE
// Step 7. Futility pruning: child node (skipped when in check)
if ( !PvNode
- && !ss->skipNullMove
&& depth < 7 * ONE_PLY
&& eval - futility_margin(depth) >= beta
&& eval < VALUE_KNOWN_WIN // Do not return unproven wins
// Step 8. Null move search with verification search (is omitted in PV nodes)
if ( !PvNode
- && !ss->skipNullMove
&& depth >= 2 * ONE_PLY
&& eval >= beta
&& pos.non_pawn_material(pos.side_to_move()))
Depth R = (3 + depth / 4 + std::min((eval - beta) / PawnValueMg, 3)) * ONE_PLY;
pos.do_null_move(st);
- (ss+1)->skipNullMove = true;
+ (ss+1)->skipEarlyPruning = true;
nullValue = depth-R < ONE_PLY ? -qsearch<NonPV, false>(pos, ss+1, -beta, -beta+1, DEPTH_ZERO)
: - search<NonPV, false>(pos, ss+1, -beta, -beta+1, depth-R, !cutNode);
- (ss+1)->skipNullMove = false;
+ (ss+1)->skipEarlyPruning = false;
pos.undo_null_move();
if (nullValue >= beta)
return nullValue;
// Do verification search at high depths
- ss->skipNullMove = true;
+ ss->skipEarlyPruning = true;
Value v = depth-R < ONE_PLY ? qsearch<NonPV, false>(pos, ss, beta-1, beta, DEPTH_ZERO)
: search<NonPV, false>(pos, ss, beta-1, beta, depth-R, false);
- ss->skipNullMove = false;
+ ss->skipEarlyPruning = false;
if (v >= beta)
return nullValue;
// prune the previous move.
if ( !PvNode
&& depth >= 5 * ONE_PLY
- && !ss->skipNullMove
&& abs(beta) < VALUE_MATE_IN_MAX_PLY)
{
Value rbeta = std::min(beta + 200, VALUE_INFINITE);
&& (PvNode || ss->staticEval + 256 >= beta))
{
Depth d = 2 * (depth - 2 * ONE_PLY) - (PvNode ? DEPTH_ZERO : depth / 2);
- ss->skipNullMove = true;
+ ss->skipEarlyPruning = true;
search<PvNode ? PV : NonPV, false>(pos, ss, alpha, beta, d / 2, true);
- ss->skipNullMove = false;
+ ss->skipEarlyPruning = false;
tte = TT.probe(posKey);
ttMove = tte ? tte->move() : MOVE_NONE;
if (PvNode)
(ss+1)->pv = NULL;
- ext = DEPTH_ZERO;
+ extension = DEPTH_ZERO;
captureOrPromotion = pos.capture_or_promotion(move);
givesCheck = type_of(move) == NORMAL && !ci.dcCandidates
// Step 12. Extend checks
if (givesCheck && pos.see_sign(move) >= VALUE_ZERO)
- ext = ONE_PLY;
+ extension = ONE_PLY;
// Singular extension search. If all moves but one fail low on a search of
// (alpha-s, beta-s), and just one fails high on (alpha, beta), then that move
// ttValue minus a margin then we extend the ttMove.
if ( singularExtensionNode
&& move == ttMove
- && !ext
+ && !extension
&& pos.legal(move, ci.pinned))
{
Value rBeta = ttValue - 2 * depth / ONE_PLY;
ss->excludedMove = move;
- ss->skipNullMove = true;
+ ss->skipEarlyPruning = true;
value = search<NonPV, false>(pos, ss, rBeta - 1, rBeta, depth / 2, cutNode);
- ss->skipNullMove = false;
+ ss->skipEarlyPruning = false;
ss->excludedMove = MOVE_NONE;
if (value < rBeta)
- ext = ONE_PLY;
+ extension = ONE_PLY;
}
// Update the current move (this must be done after singular extension search)
- newDepth = depth - ONE_PLY + ext;
+ newDepth = depth - ONE_PLY + extension;
// Step 13. Pruning at shallow depth (exclude PV nodes)
if ( !PvNode
Move Skill::pick_move() {
- static RKISS rk;
-
- // PRNG sequence should be not deterministic
- for (int i = Time::now() % 50; i > 0; --i)
- rk.rand<unsigned>();
+ // PRNG sequence should be non-deterministic, so we seed it with the time at init
+ static PRNG rng(Time::now());
// RootMoves are already sorted by score in descending order
int variance = std::min(RootMoves[0].score - RootMoves[candidates - 1].score, PawnValueMg);
int weakness = 120 - 2 * level;
- int max_s = -VALUE_INFINITE;
+ int maxScore = -VALUE_INFINITE;
best = MOVE_NONE;
// Choose best move. For each move score we add two terms both dependent on
// then we choose the move with the resulting highest score.
for (size_t i = 0; i < candidates; ++i)
{
- int s = RootMoves[i].score;
+ int score = RootMoves[i].score;
// Don't allow crazy blunders even at very low skills
- if (i > 0 && RootMoves[i - 1].score > s + 2 * PawnValueMg)
+ if (i > 0 && RootMoves[i - 1].score > score + 2 * PawnValueMg)
break;
// This is our magic formula
- s += ( weakness * int(RootMoves[0].score - s)
- + variance * (rk.rand<unsigned>() % weakness)) / 128;
+ score += ( weakness * int(RootMoves[0].score - score)
+ + variance * (rng.rand<unsigned>() % weakness)) / 128;
- if (s > max_s)
+ if (score > maxScore)
{
- max_s = s;
+ maxScore = score;
best = RootMoves[i].pv[0];
}
}
continue;
Depth d = updated ? depth : depth - ONE_PLY;
- Value v = updated ? RootMoves[i].score : RootMoves[i].prevScore;
+ Value v = updated ? RootMoves[i].score : RootMoves[i].previousScore;
bool tb = TB::RootInTB && abs(v) < VALUE_MATE - MAX_PLY;
v = tb ? TB::Score : v;
projects / stockfish / blobdiff