#include <iostream>
#include <sstream>
-#include "bitcount.h"
#include "book.h"
#include "evaluate.h"
#include "history.h"
// 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) };
- // The main transposition table
- TranspositionTable TT;
-
/// Variables initialized by UCI options
- // Adjustable playing strength
- int Slowdown = 0;
- const int SlowdownArray[32] = {
- 19, 41, 70, 110, 160, 230, 320, 430, 570, 756, 1000, 1300, 1690, 2197,
- 2834, 3600, 4573, 5809, 7700, 9863, 12633, 16181, 20726, 26584, 34005,
- 43557, 55792, 71463, 91536, 117247, 150180, 192363
- };
- int Strength;
- const int MaxStrength = 25;
-
// Minimum number of full depth (i.e. non-reduced) moves at PV and non-PV nodes
int LMRPVMoves, LMRNonPVMoves; // heavy SMP read access for the latter
Value qsearch(Position& pos, SearchStack ss[], Value alpha, Value beta, Depth depth, int ply, int threadID);
void sp_search(SplitPoint* sp, int threadID);
void sp_search_pv(SplitPoint* sp, int threadID);
- void init_node(const Position& pos, SearchStack ss[], int ply, int threadID);
+ void init_node(SearchStack ss[], int ply, int threadID);
void update_pv(SearchStack ss[], int ply);
void sp_update_pv(SearchStack* pss, SearchStack ss[], int ply);
bool connected_moves(const Position& pos, Move m1, Move m2);
bool ok_to_history(const Position& pos, Move m);
void update_history(const Position& pos, Move m, Depth depth, Move movesSearched[], int moveCount);
void update_killers(Move m, SearchStack& ss);
- void slowdown(const Position& pos);
- void build_pv(const Position& pos, Move pv[]);
bool fail_high_ply_1();
int current_search_time();
void ponderhit();
void print_current_line(SearchStack ss[], int ply, int threadID);
void wait_for_stop_or_ponderhit();
+ void init_ss_array(SearchStack ss[]);
void idle_loop(int threadID, SplitPoint* waitSp);
void init_split_point_stack();
read_weights(pos.side_to_move());
- // Set the number of active threads. If UCI_LimitStrength is enabled, never
- // use more than one thread.
- int newActiveThreads =
- get_option_value_bool("UCI_LimitStrength")? 1 : get_option_value_int("Threads");
+ // Set the number of active threads
+ int newActiveThreads = get_option_value_int("Threads");
if (newActiveThreads != ActiveThreads)
{
ActiveThreads = newActiveThreads;
for (int i = 1; i < ActiveThreads; i++)
assert(thread_is_available(i, 0));
- // Set playing strength
- if (get_option_value_bool("UCI_LimitStrength"))
- {
- Strength = (get_option_value_int("UCI_Elo") - 2100) / 25;
- Slowdown =
- (Strength == MaxStrength)? 0 : SlowdownArray[Max(0, 31-Strength)];
- }
- else
- {
- Strength = MaxStrength;
- Slowdown = 0;
- }
-
// Set thinking time
int myTime = time[side_to_move];
int myIncrement = increment[side_to_move];
NodesBetweenPolls = Min(MaxNodes, 30000);
InfiniteSearch = true; // HACK
}
- else if (Slowdown) {
- if (Slowdown > 50000) NodesBetweenPolls = 30;
- else if (Slowdown > 10000) NodesBetweenPolls = 100;
- else if (Slowdown > 1000) NodesBetweenPolls = 500;
- else if (Slowdown > 100) NodesBetweenPolls = 3000;
- else NodesBetweenPolls = 15000;
- }
else
NodesBetweenPolls = 30000;
{
Value v = id_loop(pos, searchMoves);
loseOnTime = ( UseLSNFiltering
- && myTime < LSNTime
- && myIncrement == 0
- && v < -LSNValue);
+ && myTime < LSNTime
+ && myIncrement == 0
+ && v < -LSNValue);
}
else
{
// searchMoves are verified, copied, scored and sorted
RootMoveList rml(p, searchMoves);
+ // Print RootMoveList c'tor startup scoring to the standard output,
+ // so that we print information also for iteration 1.
+ std::cout << "info depth " << 1 << "\ninfo depth " << 1
+ << " score " << value_to_string(rml.get_move_score(0))
+ << " time " << current_search_time()
+ << " nodes " << nodes_searched()
+ << " nps " << nps()
+ << " pv " << rml.get_move(0) << "\n";
+
// Initialize
TT.new_search();
H.clear();
- for (int i = 0; i < 3; i++)
- {
- ss[i].init(i);
- ss[i].initKillers();
- }
+ init_ss_array(ss);
IterationInfo[1] = IterationInfoType(rml.get_move_score(0), rml.get_move_score(0));
Iteration = 1;
// Decide search depth for this move
bool moveIsCapture = pos.move_is_capture(move);
bool dangerous;
- ext = extension(pos, move, true, pos.move_is_capture(move), pos.move_is_check(move), false, false, &dangerous);
+ ext = extension(pos, move, true, moveIsCapture, pos.move_is_check(move), false, false, &dangerous);
newDepth = (Iteration - 2) * OnePly + ext + InitialDepth;
// Make the move, and search it
}
else
{
- if (newDepth >= 3*OnePly
- && i + MultiPV >= LMRPVMoves
+ if ( newDepth >= 3*OnePly
+ && i >= MultiPV + LMRPVMoves
&& !dangerous
&& !moveIsCapture
&& !move_is_promotion(move)
{
ss[0].reduction = OnePly;
value = -search(pos, ss, -alpha, newDepth-OnePly, 1, true, 0);
- }
- else
+ } else
value = alpha + 1; // Just to trigger next condition
- if(value > alpha)
+
+ if (value > alpha)
{
value = -search(pos, ss, -alpha, newDepth, 1, true, 0);
if (value > alpha)
// Update PV
rml.set_move_score(i, value);
update_pv(ss, 0);
- build_pv(pos, ss[0].pv);
+ TT.extract_pv(pos, ss[0].pv, PLY_MAX);
rml.set_move_pv(i, ss[0].pv);
if (MultiPV == 1)
// Print search information to the standard output
std::cout << "info depth " << Iteration
<< " score " << value_to_string(value)
+ << ((value >= beta)?
+ " lowerbound" : ((value <= alpha)? " upperbound" : ""))
<< " time " << current_search_time()
<< " nodes " << nodes_searched()
<< " nps " << nps()
// Initialize, and make an early exit in case of an aborted search,
// an instant draw, maximum ply reached, etc.
- init_node(pos, ss, ply, threadID);
+ init_node(ss, ply, threadID);
// After init_node() that calls poll()
if (AbortSearch || thread_should_stop(threadID))
// Initialize a MovePicker object for the current position, and prepare
// to search all moves
- MovePicker mp = MovePicker(pos, ttMove, depth, H, &ss[ply]);
-
Move move, movesSearched[256];
int moveCount = 0;
Value value, bestValue = -VALUE_INFINITE;
- Bitboard dcCandidates = mp.discovered_check_candidates();
Color us = pos.side_to_move();
bool isCheck = pos.is_check();
bool mateThreat = pos.has_mate_threat(opposite_color(us));
+ MovePicker mp = MovePicker(pos, ttMove, depth, H, &ss[ply]);
+ Bitboard dcCandidates = mp.discovered_check_candidates();
+
// Loop through all legal moves until no moves remain or a beta cutoff
// occurs.
while ( alpha < beta
{
assert(move_is_ok(move));
- bool singleReply = (isCheck && mp.number_of_moves() == 1);
+ bool singleReply = (isCheck && mp.number_of_evasions() == 1);
bool moveIsCheck = pos.move_is_check(move, dcCandidates);
bool moveIsCapture = pos.move_is_capture(move);
// Initialize, and make an early exit in case of an aborted search,
// an instant draw, maximum ply reached, etc.
- init_node(pos, ss, ply, threadID);
+ init_node(ss, ply, threadID);
// After init_node() that calls poll()
if (AbortSearch || thread_should_stop(threadID))
bool useFutilityPruning = depth < SelectiveDepth
&& !isCheck;
+ // Avoid calling evaluate() if we already have the score in TT
+ if (tte && (tte->type() & VALUE_TYPE_EVAL))
+ futilityValue = value_from_tt(tte->value(), ply) + FutilityMargins[int(depth) - 2];
+
// Loop through all legal moves until no moves remain or a beta cutoff
// occurs.
while ( bestValue < beta
{
assert(move_is_ok(move));
- bool singleReply = (isCheck && mp.number_of_moves() == 1);
+ bool singleReply = (isCheck && mp.number_of_evasions() == 1);
bool moveIsCheck = pos.move_is_check(move, dcCandidates);
bool moveIsCapture = pos.move_is_capture(move);
// Initialize, and make an early exit in case of an aborted search,
// an instant draw, maximum ply reached, etc.
- init_node(pos, ss, ply, threadID);
+ init_node(ss, ply, threadID);
// After init_node() that calls poll()
if (AbortSearch || thread_should_stop(threadID))
if (isCheck)
staticValue = -VALUE_INFINITE;
- else if (tte && tte->type() == VALUE_TYPE_EVAL)
+ else if (tte && (tte->type() & VALUE_TYPE_EVAL))
{
// Use the cached evaluation score if possible
assert(ei.futilityMargin == Value(0));
{
// Store the score to avoid a future costly evaluation() call
if (!isCheck && !tte && ei.futilityMargin == 0)
- TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_EVAL, Depth(-127*OnePly), MOVE_NONE);
+ TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_EV_LO, Depth(-127*OnePly), MOVE_NONE);
return bestValue;
}
Move m = ss[ply].pv[ply];
if (!pvNode)
{
+ // If bestValue isn't changed it means it is still the static evaluation of
+ // the node, so keep this info to avoid a future costly evaluation() call.
+ ValueType type = (bestValue == staticValue && !ei.futilityMargin ? VALUE_TYPE_EV_UP : VALUE_TYPE_UPPER);
Depth d = (depth == Depth(0) ? Depth(0) : Depth(-1));
+
if (bestValue < beta)
- TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_UPPER, d, MOVE_NONE);
+ TT.store(pos.get_key(), value_to_tt(bestValue, ply), type, d, MOVE_NONE);
else
TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_LOWER, d, m);
}
bool includeAllMoves = (searchMoves[0] == MOVE_NONE);
// Generate all legal moves
- int lm_count = generate_legal_moves(pos, mlist);
+ MoveStack* last = generate_moves(pos, mlist);
// Add each move to the moves[] array
- for (int i = 0; i < lm_count; i++)
+ for (MoveStack* cur = mlist; cur != last; cur++)
{
bool includeMove = includeAllMoves;
for (int k = 0; !includeMove && searchMoves[k] != MOVE_NONE; k++)
- includeMove = (searchMoves[k] == mlist[i].move);
+ includeMove = (searchMoves[k] == cur->move);
if (!includeMove)
continue;
// Find a quick score for the move
StateInfo st;
SearchStack ss[PLY_MAX_PLUS_2];
+ init_ss_array(ss);
- moves[count].move = mlist[i].move;
+ moves[count].move = cur->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);
// NodesBetweenPolls nodes, init_node() also calls poll(), which polls
// for user input and checks whether it is time to stop the search.
- void init_node(const Position& pos, SearchStack ss[], int ply, int threadID) {
+ void init_node(SearchStack ss[], int ply, int threadID) {
assert(ply >= 0 && ply < PLY_MAX);
assert(threadID >= 0 && threadID < ActiveThreads);
- if (Slowdown && Iteration >= 3)
- slowdown(pos);
-
Threads[threadID].nodes++;
if (threadID == 0)
// the second move is assumed to be a move from the current position.
bool connected_moves(const Position& pos, Move m1, Move m2) {
+
Square f1, t1, f2, t2;
+ Piece p;
assert(move_is_ok(m1));
assert(move_is_ok(m2));
return true;
// Case 4: The destination square for m2 is attacked by the moving piece in m1
- if (pos.piece_attacks_square(pos.piece_on(t1), t1, t2))
+ p = pos.piece_on(t1);
+ if (bit_is_set(pos.attacks_from(p, t1), t2))
return true;
// Case 5: Discovered check, checking piece is the piece moved in m1
- if ( piece_is_slider(pos.piece_on(t1))
+ if ( piece_is_slider(p)
&& bit_is_set(squares_between(t1, pos.king_square(pos.side_to_move())), f2)
- && !bit_is_set(squares_between(t2, pos.king_square(pos.side_to_move())), t2))
+ && !bit_is_set(squares_between(t1, pos.king_square(pos.side_to_move())), t2))
{
Bitboard occ = pos.occupied_squares();
Color us = pos.side_to_move();
Square ksq = pos.king_square(us);
clear_bit(&occ, f2);
- if (pos.type_of_piece_on(t1) == BISHOP)
+ if (type_of_piece(p) == BISHOP)
{
if (bit_is_set(bishop_attacks_bb(ksq, occ), t1))
return true;
}
- else if (pos.type_of_piece_on(t1) == ROOK)
+ else if (type_of_piece(p) == ROOK)
{
if (bit_is_set(rook_attacks_bb(ksq, occ), t1))
return true;
}
else
{
- assert(pos.type_of_piece_on(t1) == QUEEN);
+ assert(type_of_piece(p) == QUEEN);
if (bit_is_set(queen_attacks_bb(ksq, occ), t1))
return true;
}
if (pos.type_of_piece_on(move_from(m)) == PAWN)
{
- if (pos.move_is_pawn_push_to_7th(m))
+ Color c = pos.side_to_move();
+ if (relative_rank(c, move_to(m)) == RANK_7)
{
result += PawnPushTo7thExtension[pvNode];
*dangerous = true;
}
- if (pos.move_is_passed_pawn_push(m))
+ if (pos.pawn_is_passed(c, move_to(m)))
{
result += PassedPawnExtension[pvNode];
*dangerous = true;
}
- // slowdown() simply wastes CPU cycles doing nothing useful. It's used
- // in strength handicap mode.
-
- void slowdown(const Position &pos) {
- int i, n;
- n = Slowdown;
- for (i = 0; i < n; i++) {
- Square s = Square(i&63);
- if (count_1s(pos.attacks_to(s)) > 63)
- std::cout << "This can't happen, but I put this string here anyway, in order to prevent the compiler from optimizing away the useless computation." << std::endl;
- }
- }
-
-
- // build_pv() extends a PV by adding moves from the transposition table at
- // the end. This should ensure that the PV is almost always at least two
- // plies long, which is important, because otherwise we will often get
- // single-move PVs when the search stops while failing high, and a
- // single-move PV means that we don't have a ponder move.
-
- void build_pv(const Position& pos, Move pv[]) {
- int ply;
- Position p(pos);
- StateInfo st[100];
-
- for (ply = 0; pv[ply] != MOVE_NONE; ply++)
- p.do_move(pv[ply], st[ply]);
-
- bool stop;
- const TTEntry* tte;
- for (stop = false, tte = TT.retrieve(p.get_key());
- tte && tte->move() != MOVE_NONE && !stop;
- tte = TT.retrieve(p.get_key()), ply++)
- {
- if (!move_is_legal(p, tte->move(), p.pinned_pieces(p.side_to_move())))
- break;
- pv[ply] = tte->move();
- p.do_move(pv[ply], st[ply]);
- for (int j = 0; j < ply; j++)
- if (st[j].key == p.get_key()) stop = true;
- }
- pv[ply] = MOVE_NONE;
- }
-
-
// fail_high_ply_1() checks if some thread is currently resolving a fail
// high at ply 1 at the node below the first root node. This information
// is used for time managment.
}
+ // init_ss_array() does a fast reset of the first entries of a SearchStack array
+
+ void init_ss_array(SearchStack ss[]) {
+
+ for (int i = 0; i < 3; i++)
+ {
+ ss[i].init(i);
+ ss[i].initKillers();
+ }
+ }
+
+
// wait_for_stop_or_ponderhit() is called when the maximum depth is reached
// while the program is pondering. The point is to work around a wrinkle in
// the UCI protocol: When pondering, the engine is not allowed to give a
projects / stockfish / blobdiff