#include "lock.h"
#include "san.h"
#include "search.h"
+#include "timeman.h"
#include "thread.h"
#include "tt.h"
#include "ucioption.h"
namespace {
- /// Types
+ // Maximum number of allowed moves per position
+ const int MOVES_MAX = 256;
+
+ // Types
enum NodeType { NonPV, PV };
// Set to true to force running with one thread.
int active_threads() const { return ActiveThreads; }
void set_active_threads(int newActiveThreads) { ActiveThreads = newActiveThreads; }
void incrementNodeCounter(int threadID) { threads[threadID].nodes++; }
- void incrementBetaCounter(Color us, Depth d, int threadID) { threads[threadID].betaCutOffs[us] += unsigned(d); }
void resetNodeCounters();
- void resetBetaCounters();
int64_t nodes_searched() const;
- void get_beta_counters(Color us, int64_t& our, int64_t& their) const;
bool available_thread_exists(int master) const;
bool thread_is_available(int slave, int master) const;
bool thread_should_stop(int threadID) const;
template <bool Fake>
void split(const Position& pos, SearchStack* ss, int ply, Value* alpha, const Value beta, Value* bestValue,
- Depth depth, bool mateThreat, int* moveCount, MovePicker* mp, bool pvNode);
+ Depth depth, Move threatMove, bool mateThreat, int* moveCount, MovePicker* mp, bool pvNode);
private:
friend void poll();
struct RootMove {
- RootMove() { nodes = cumulativeNodes = ourBeta = theirBeta = 0ULL; }
+ RootMove() : mp_score(0), nodes(0) {}
// RootMove::operator<() is the comparison function used when
// sorting the moves. A move m1 is considered to be better
// have equal score but m1 has the higher beta cut-off count.
bool operator<(const RootMove& m) const {
- return score != m.score ? score < m.score : theirBeta <= m.theirBeta;
+ return score != m.score ? score < m.score : mp_score <= m.mp_score;
}
Move move;
Value score;
- int64_t nodes, cumulativeNodes, ourBeta, theirBeta;
+ int mp_score;
+ int64_t nodes;
Move pv[PLY_MAX_PLUS_2];
};
public:
RootMoveList(Position& pos, Move searchMoves[]);
+ Move move(int moveNum) const { return moves[moveNum].move; }
+ Move move_pv(int moveNum, int i) const { return moves[moveNum].pv[i]; }
int move_count() const { return count; }
- Move get_move(int moveNum) const { return moves[moveNum].move; }
- Value get_move_score(int moveNum) const { return moves[moveNum].score; }
+ Value move_score(int moveNum) const { return moves[moveNum].score; }
+ int64_t move_nodes(int moveNum) const { return moves[moveNum].nodes; }
+ void add_move_nodes(int moveNum, int64_t nodes) { moves[moveNum].nodes += nodes; }
void set_move_score(int moveNum, Value score) { moves[moveNum].score = score; }
- Move get_move_pv(int moveNum, int i) const { return moves[moveNum].pv[i]; }
- int64_t get_move_cumulative_nodes(int moveNum) const { return moves[moveNum].cumulativeNodes; }
- void set_move_nodes(int moveNum, int64_t nodes);
- void set_beta_counters(int moveNum, int64_t our, int64_t their);
void set_move_pv(int moveNum, const Move pv[]);
+ void score_moves(const Position& pos);
void sort();
void sort_multipv(int n);
private:
- static const int MaxRootMoves = 500;
- RootMove moves[MaxRootMoves];
+ RootMove moves[MOVES_MAX];
int count;
};
+ // When formatting a move for std::cout we must know if we are in Chess960
+ // or not. To keep using the handy operator<<() on the move the trick is to
+ // embed this flag in the stream itself. Function-like named enum set960 is
+ // used as a custom manipulator and the stream internal general-purpose array,
+ // accessed through ios_base::iword(), is used to pass the flag to the move's
+ // operator<<() that will use it to properly format castling moves.
+ enum set960 {};
+
+ std::ostream& operator<< (std::ostream& os, const set960& m) {
+
+ os.iword(0) = int(m);
+ return os;
+ }
+
+
/// Adjustments
// 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)); }
- // Step 8. Null move search with verification search
-
- // Null move margin. A null move search will not be done if the static
- // evaluation of the position is more than NullMoveMargin below beta.
- 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] = { 8 * 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.
const Value FutilityMarginQS = Value(0x80);
// Futility lookup tables (initialized at startup) and their getter functions
- int32_t FutilityMarginsMatrix[16][64]; // [depth][moveNumber]
+ Value 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 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.
const Value EasyMoveMargin = Value(0x200);
- // Last seconds noise filtering (LSN)
- const bool UseLSNFiltering = true;
- const int LSNTime = 100; // In milliseconds
- const Value LSNValue = value_from_centipawns(200);
- bool loseOnTime = false;
-
/// Global variables
int MultiPV;
// Time managment variables
- int SearchStartTime, MaxNodes, MaxDepth, MaxSearchTime;
- int AbsoluteMaxSearchTime, ExtraSearchTime, ExactMaxTime;
+ int SearchStartTime, MaxNodes, MaxDepth, ExactMaxTime;
bool UseTimeManagement, InfiniteSearch, PonderSearch, StopOnPonderhit;
bool FirstRootMove, AbortSearch, Quit, AspirationFailLow;
+ TimeManager TimeMgr;
// Log file
bool UseLogFile;
// Multi-threads related variables
Depth MinimumSplitDepth;
int MaxThreadsPerSplitPoint;
- ThreadsManager TM;
+ ThreadsManager ThreadsMgr;
// Node counters, used only by thread[0] but try to keep in different cache
// lines (64 bytes each) from the heavy multi-thread read accessed variables.
bool connected_moves(const Position& pos, Move m1, Move m2);
bool value_is_mate(Value value);
+ Value value_to_tt(Value v, int ply);
+ Value value_from_tt(Value v, int ply);
bool move_is_killer(Move m, SearchStack* ss);
bool ok_to_use_TT(const TTEntry* tte, Depth depth, Value beta, int ply);
bool connected_threat(const Position& pos, Move m, Move threat);
void update_gains(const Position& pos, Move move, Value before, Value after);
int current_search_time();
+ std::string value_to_uci(Value v);
int nps();
void poll();
void ponderhit();
void wait_for_stop_or_ponderhit();
void init_ss_array(SearchStack* ss, int size);
void print_pv_info(const Position& pos, Move pv[], Value alpha, Value beta, Value value);
+ void insert_pv_in_tt(const Position& pos, Move pv[]);
+ void extract_pv_from_tt(const Position& pos, Move bestMove, Move pv[]);
#if !defined(_MSC_VER)
void *init_thread(void *threadID);
/// init_threads(), exit_threads() and nodes_searched() are helpers to
/// give accessibility to some TM methods from outside of current file.
-void init_threads() { TM.init_threads(); }
-void exit_threads() { TM.exit_threads(); }
-int64_t nodes_searched() { return TM.nodes_searched(); }
+void init_threads() { ThreadsMgr.init_threads(); }
+void exit_threads() { ThreadsMgr.exit_threads(); }
+int64_t nodes_searched() { return ThreadsMgr.nodes_searched(); }
/// init_search() is called during startup. It initializes various lookup tables
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
for (hd = 1; hd < 64; hd++) for (mc = 1; mc < 64; mc++)
{
- double pvRed = log(double(hd)) * log(double(mc)) / 3.0;
- double nonPVRed = log(double(hd)) * log(double(mc)) / 1.5;
- 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);
+ 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(ONE_PLY)) : 0);
+ ReductionMatrix[NonPV][hd][mc] = (int8_t) (nonPVRed >= 1.0 ? floor(nonPVRed * int(ONE_PLY)) : 0);
}
// Init futility margins array
for (d = 1; d < 16; d++) for (mc = 0; mc < 64; mc++)
- FutilityMarginsMatrix[d][mc] = 112 * int(log(double(d * d) / 2) / log(2.0) + 1.001) - 8 * mc + 45;
+ FutilityMarginsMatrix[d][mc] = Value(112 * int(log(double(d * d) / 2) / log(2.0) + 1.001) - 8 * mc + 45);
// Init futility move count array
for (d = 0; d < 32; d++)
}
-// SearchStack::init() initializes a search stack entry.
-// Called at the beginning of search() when starting to examine a new node.
-void SearchStack::init() {
-
- currentMove = threatMove = bestMove = MOVE_NONE;
- reduction = Depth(0);
- eval = VALUE_NONE;
-}
-
-// SearchStack::initKillers() initializes killers for a search stack entry
-void SearchStack::initKillers() {
-
- mateKiller = MOVE_NONE;
- for (int i = 0; i < KILLER_MAX; i++)
- killers[i] = MOVE_NONE;
-}
-
-
/// perft() is our utility to verify move generation is bug free. All the legal
/// moves up to given depth are generated and counted and the sum returned.
int perft(Position& pos, Depth depth)
{
+ MoveStack mlist[MOVES_MAX];
StateInfo st;
- Move move;
+ Move m;
int sum = 0;
- MovePicker mp(pos, MOVE_NONE, depth, H);
+
+ // Generate all legal moves
+ MoveStack* last = generate_moves(pos, mlist);
// If we are at the last ply we don't need to do and undo
// the moves, just to count them.
- if (depth <= OnePly) // Replace with '<' to test also qsearch
- {
- while (mp.get_next_move()) sum++;
- return sum;
- }
+ if (depth <= ONE_PLY)
+ return int(last - mlist);
// Loop through all legal moves
CheckInfo ci(pos);
- while ((move = mp.get_next_move()) != MOVE_NONE)
+ for (MoveStack* cur = mlist; cur != last; cur++)
{
- pos.do_move(move, st, ci, pos.move_is_check(move, ci));
- sum += perft(pos, depth - OnePly);
- pos.undo_move(move);
+ m = cur->move;
+ pos.do_move(m, st, ci, pos.move_is_check(m, ci));
+ sum += perft(pos, depth - ONE_PLY);
+ pos.undo_move(m);
}
return sum;
}
/// search-related global variables, and calls root_search(). It returns false
/// when a quit command is received during the search.
-bool think(const Position& pos, bool infinite, bool ponder, int side_to_move,
- int time[], int increment[], int movesToGo, int maxDepth,
- int maxNodes, int maxTime, Move searchMoves[]) {
+bool think(const Position& pos, bool infinite, bool ponder, int time[], int increment[],
+ int movesToGo, int maxDepth, int maxNodes, int maxTime, Move searchMoves[]) {
// Initialize global search variables
StopOnPonderhit = AbortSearch = Quit = AspirationFailLow = false;
- MaxSearchTime = AbsoluteMaxSearchTime = ExtraSearchTime = 0;
NodesSincePoll = 0;
- TM.resetNodeCounters();
+ ThreadsMgr.resetNodeCounters();
SearchStartTime = get_system_time();
ExactMaxTime = maxTime;
MaxDepth = maxDepth;
}
}
- // Reset loseOnTime flag at the beginning of a new game
- if (button_was_pressed("New Game"))
- loseOnTime = false;
-
// Read UCI option values
TT.set_size(get_option_value_int("Hash"));
if (button_was_pressed("Clear Hash"))
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");
UseLogFile = get_option_value_bool("Use Search Log");
if (UseLogFile)
// Set the number of active threads
int newActiveThreads = get_option_value_int("Threads");
- if (newActiveThreads != TM.active_threads())
+ if (newActiveThreads != ThreadsMgr.active_threads())
{
- TM.set_active_threads(newActiveThreads);
- init_eval(TM.active_threads());
+ ThreadsMgr.set_active_threads(newActiveThreads);
+ init_eval(ThreadsMgr.active_threads());
}
// Wake up sleeping threads
- TM.wake_sleeping_threads();
+ ThreadsMgr.wake_sleeping_threads();
// Set thinking time
- int myTime = time[side_to_move];
- int myIncrement = increment[side_to_move];
+ int myTime = time[pos.side_to_move()];
+ int myIncrement = increment[pos.side_to_move()];
if (UseTimeManagement)
- {
- if (!movesToGo) // Sudden death time control
- {
- if (myIncrement)
- {
- MaxSearchTime = myTime / 30 + myIncrement;
- AbsoluteMaxSearchTime = Max(myTime / 4, myIncrement - 100);
- }
- else // Blitz game without increment
- {
- MaxSearchTime = myTime / 30;
- AbsoluteMaxSearchTime = myTime / 8;
- }
- }
- else // (x moves) / (y minutes)
- {
- if (movesToGo == 1)
- {
- MaxSearchTime = myTime / 2;
- AbsoluteMaxSearchTime = (myTime > 3000)? (myTime - 500) : ((myTime * 3) / 4);
- }
- else
- {
- MaxSearchTime = myTime / Min(movesToGo, 20);
- AbsoluteMaxSearchTime = Min((4 * myTime) / movesToGo, myTime / 3);
- }
- }
-
- if (get_option_value_bool("Ponder"))
- {
- MaxSearchTime += MaxSearchTime / 4;
- MaxSearchTime = Min(MaxSearchTime, AbsoluteMaxSearchTime);
- }
- }
+ TimeMgr.init(myTime, myIncrement, movesToGo, pos.startpos_ply_counter());
// Set best NodesBetweenPolls interval to avoid lagging under
// heavy time pressure.
<< " increment: " << myIncrement
<< " moves to go: " << movesToGo << endl;
- // LSN filtering. Used only for developing purposes, disabled by default
- if ( UseLSNFiltering
- && loseOnTime)
- {
- // Step 2. If after last move we decided to lose on time, do it now!
- while (SearchStartTime + myTime + 1000 > get_system_time())
- /* wait here */;
- }
-
// We're ready to start thinking. Call the iterative deepening loop function
- Value v = id_loop(pos, searchMoves);
-
- if (UseLSNFiltering)
- {
- // Step 1. If this is sudden death game and our position is hopeless,
- // decide to lose on time.
- if ( !loseOnTime // If we already lost on time, go to step 3.
- && myTime < LSNTime
- && myIncrement == 0
- && movesToGo == 0
- && v < -LSNValue)
- {
- loseOnTime = true;
- }
- else if (loseOnTime)
- {
- // Step 3. Now after stepping over the time limit, reset flag for next match.
- loseOnTime = false;
- }
- }
+ id_loop(pos, searchMoves);
if (UseLogFile)
LogFile.close();
- TM.put_threads_to_sleep();
+ ThreadsMgr.put_threads_to_sleep();
return !Quit;
}
// Print RootMoveList startup scoring to the standard output,
// so to output information also for iteration 1.
- cout << "info depth " << 1
+ cout << set960(p.is_chess960()) // Is enough to set once at the beginning
+ << "info depth " << 1
<< "\ninfo depth " << 1
- << " score " << value_to_string(rml.get_move_score(0))
+ << " score " << value_to_uci(rml.move_score(0))
<< " time " << current_search_time()
- << " nodes " << TM.nodes_searched()
+ << " nodes " << ThreadsMgr.nodes_searched()
<< " nps " << nps()
- << " pv " << rml.get_move(0) << "\n";
+ << " pv " << rml.move(0) << "\n";
// Initialize
TT.new_search();
H.clear();
init_ss_array(ss, PLY_MAX_PLUS_2);
pv[0] = pv[1] = MOVE_NONE;
- ValueByIteration[1] = rml.get_move_score(0);
+ ValueByIteration[1] = rml.move_score(0);
Iteration = 1;
// Is one move significantly better than others after initial scoring ?
if ( rml.move_count() == 1
- || rml.get_move_score(0) > rml.get_move_score(1) + EasyMoveMargin)
- EasyMove = rml.get_move(0);
+ || rml.move_score(0) > rml.move_score(1) + EasyMoveMargin)
+ EasyMove = rml.move(0);
// Iterative deepening loop
while (Iteration < PLY_MAX)
// Write PV to transposition table, in case the relevant entries have
// been overwritten during the search.
- TT.insert_pv(p, pv);
+ insert_pv_in_tt(p, pv);
if (AbortSearch)
break; // Value cannot be trusted. Break out immediately!
stopSearch = true;
// Stop search early if one move seems to be much better than the others
- int64_t nodes = TM.nodes_searched();
+ int64_t nodes = ThreadsMgr.nodes_searched();
if ( Iteration >= 8
&& EasyMove == pv[0]
- && ( ( rml.get_move_cumulative_nodes(0) > (nodes * 85) / 100
- && current_search_time() > MaxSearchTime / 16)
- ||( rml.get_move_cumulative_nodes(0) > (nodes * 98) / 100
- && current_search_time() > MaxSearchTime / 32)))
+ && ( ( rml.move_nodes(0) > (nodes * 85) / 100
+ && current_search_time() > TimeMgr.available_time() / 16)
+ ||( rml.move_nodes(0) > (nodes * 98) / 100
+ && current_search_time() > TimeMgr.available_time() / 32)))
stopSearch = true;
// Add some extra time if the best move has changed during the last two iterations
if (Iteration > 5 && Iteration <= 50)
- ExtraSearchTime = BestMoveChangesByIteration[Iteration] * (MaxSearchTime / 2)
- + BestMoveChangesByIteration[Iteration-1] * (MaxSearchTime / 3);
+ TimeMgr.pv_unstability(BestMoveChangesByIteration[Iteration],
+ BestMoveChangesByIteration[Iteration-1]);
// Stop search if most of MaxSearchTime is consumed at the end of the
// iteration. We probably don't have enough time to search the first
// move at the next iteration anyway.
- if (current_search_time() > ((MaxSearchTime + ExtraSearchTime) * 80) / 128)
+ if (current_search_time() > (TimeMgr.available_time() * 80) / 128)
stopSearch = true;
if (stopSearch)
wait_for_stop_or_ponderhit();
else
// Print final search statistics
- cout << "info nodes " << TM.nodes_searched()
+ cout << "info nodes " << ThreadsMgr.nodes_searched()
<< " nps " << nps()
- << " time " << current_search_time()
- << " hashfull " << TT.full() << endl;
+ << " time " << current_search_time() << endl;
// Print the best move and the ponder move to the standard output
if (pv[0] == MOVE_NONE)
{
- pv[0] = rml.get_move(0);
+ pv[0] = rml.move(0);
pv[1] = MOVE_NONE;
}
if (dbg_show_hit_rate)
dbg_print_hit_rate(LogFile);
- LogFile << "\nNodes: " << TM.nodes_searched()
+ LogFile << "\nNodes: " << ThreadsMgr.nodes_searched()
<< "\nNodes/second: " << nps()
<< "\nBest move: " << move_to_san(p, pv[0]);
<< move_to_san(p, pv[1]) // Works also with MOVE_NONE
<< endl;
}
- return rml.get_move_score(0);
+ return rml.move_score(0);
}
Value root_search(Position& pos, SearchStack* ss, Move* pv, RootMoveList& rml, Value* alphaPtr, Value* betaPtr) {
- EvalInfo ei;
StateInfo st;
CheckInfo ci(pos);
int64_t nodes;
Move move;
Depth depth, ext, newDepth;
- Value value, alpha, beta;
+ Value value, evalMargin, alpha, beta;
bool isCheck, moveIsCheck, captureOrPromotion, dangerous;
int researchCountFH, researchCountFL;
alpha = *alphaPtr;
beta = *betaPtr;
isCheck = pos.is_check();
+ depth = (Iteration - 2) * ONE_PLY + InitialDepth;
+
+ // Step 1. Initialize node (polling is omitted at root)
+ ss->currentMove = ss->bestMove = MOVE_NONE;
- // Step 1. Initialize node and poll (omitted at root, init_ss_array() has already initialized root node)
// Step 2. Check for aborted search (omitted at root)
// Step 3. Mate distance pruning (omitted at root)
// Step 4. Transposition table lookup (omitted at root)
// Step 5. Evaluate the position statically
// At root we do this only to get reference value for child nodes
- if (!isCheck)
- ss->eval = evaluate(pos, ei);
+ ss->eval = isCheck ? VALUE_NONE : evaluate(pos, evalMargin);
// Step 6. Razoring (omitted at root)
// Step 7. Static null move pruning (omitted at root)
while (1)
{
// Sort the moves before to (re)search
+ rml.score_moves(pos);
rml.sort();
// Step 10. Loop through all moves in the root move list
FirstRootMove = (i == 0);
// Save the current node count before the move is searched
- nodes = TM.nodes_searched();
-
- // Reset beta cut-off counters
- TM.resetBetaCounters();
+ nodes = ThreadsMgr.nodes_searched();
// Pick the next root move, and print the move and the move number to
// the standard output.
- move = ss->currentMove = rml.get_move(i);
+ move = ss->currentMove = rml.move(i);
if (current_search_time() >= 1000)
cout << "info currmove " << move
captureOrPromotion = pos.move_is_capture_or_promotion(move);
// Step 11. Decide the new search depth
- depth = (Iteration - 2) * OnePly + InitialDepth;
ext = extension<PV>(pos, move, captureOrPromotion, moveIsCheck, false, false, &dangerous);
newDepth = depth + ext;
// 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
// the score before research in case we run out of time while researching.
rml.set_move_score(i, value);
ss->bestMove = move;
- TT.extract_pv(pos, move, pv, PLY_MAX);
+ extract_pv_from_tt(pos, move, pv);
rml.set_move_pv(i, pv);
// Print information to the standard output
if (AbortSearch)
break;
- // Remember beta-cutoff and searched nodes counts for this move. The
- // info is used to sort the root moves for the next iteration.
- int64_t our, their;
- TM.get_beta_counters(pos.side_to_move(), our, their);
- rml.set_beta_counters(i, our, their);
- rml.set_move_nodes(i, TM.nodes_searched() - nodes);
+ // Remember searched nodes counts for this move
+ rml.add_move_nodes(i, ThreadsMgr.nodes_searched() - nodes);
assert(value >= -VALUE_INFINITE && value <= VALUE_INFINITE);
assert(value < beta);
// Update PV
rml.set_move_score(i, value);
ss->bestMove = move;
- TT.extract_pv(pos, move, pv, PLY_MAX);
+ extract_pv_from_tt(pos, move, pv);
rml.set_move_pv(i, pv);
if (MultiPV == 1)
for (int j = 0; j < Min(MultiPV, rml.move_count()); j++)
{
cout << "info multipv " << j + 1
- << " score " << value_to_string(rml.get_move_score(j))
+ << " score " << value_to_uci(rml.move_score(j))
<< " depth " << (j <= i ? Iteration : Iteration - 1)
<< " time " << current_search_time()
- << " nodes " << TM.nodes_searched()
+ << " nodes " << ThreadsMgr.nodes_searched()
<< " nps " << nps()
<< " pv ";
- for (int k = 0; rml.get_move_pv(j, k) != MOVE_NONE && k < PLY_MAX; k++)
- cout << rml.get_move_pv(j, k) << " ";
+ for (int k = 0; rml.move_pv(j, k) != MOVE_NONE && k < PLY_MAX; k++)
+ cout << rml.move_pv(j, k) << " ";
cout << endl;
}
- alpha = rml.get_move_score(Min(i, MultiPV - 1));
+ alpha = rml.move_score(Min(i, MultiPV - 1));
}
} // PV move or new best move
assert(beta > alpha && beta <= VALUE_INFINITE);
assert(PvNode || alpha == beta - 1);
assert(ply > 0 && ply < PLY_MAX);
- assert(pos.thread() >= 0 && pos.thread() < TM.active_threads());
+ assert(pos.thread() >= 0 && pos.thread() < ThreadsMgr.active_threads());
- Move movesSearched[256];
- EvalInfo ei;
+ Move movesSearched[MOVES_MAX];
StateInfo st;
- const TTEntry* tte;
+ const TTEntry *tte;
Key posKey;
- Move ttMove, move, excludedMove;
+ Move ttMove, move, excludedMove, threatMove;
Depth ext, newDepth;
- Value bestValue, value, oldAlpha;
- Value refinedValue, nullValue, futilityValueScaled; // Non-PV specific
+ Value bestValue, value, evalMargin, oldAlpha;
+ Value refinedValue, nullValue, futilityBase, futilityValueScaled; // Non-PV specific
bool isCheck, singleEvasion, singularExtensionNode, moveIsCheck, captureOrPromotion, dangerous;
bool mateThreat = false;
int moveCount = 0;
oldAlpha = alpha;
// Step 1. Initialize node and poll. Polling can abort search
- TM.incrementNodeCounter(threadID);
- ss->init();
- (ss+2)->initKillers();
+ ThreadsMgr.incrementNodeCounter(threadID);
+ ss->currentMove = ss->bestMove = threatMove = MOVE_NONE;
+ (ss+2)->killers[0] = (ss+2)->killers[1] = (ss+2)->mateKiller = MOVE_NONE;
if (threadID == 0 && ++NodesSincePoll > NodesBetweenPolls)
{
}
// Step 2. Check for aborted search and immediate draw
- if (AbortSearch || TM.thread_should_stop(threadID))
- return Value(0);
+ if (AbortSearch || ThreadsMgr.thread_should_stop(threadID))
+ return VALUE_ZERO;
if (pos.is_draw() || ply >= PLY_MAX - 1)
return VALUE_DRAW;
if (!PvNode && tte && ok_to_use_TT(tte, depth, beta, ply))
{
// Refresh tte entry to avoid aging
- TT.store(posKey, tte->value(), tte->type(), tte->depth(), ttMove, tte->static_value(), tte->king_danger());
+ TT.store(posKey, tte->value(), tte->type(), tte->depth(), ttMove, tte->static_value(), tte->static_value_margin());
- ss->currentMove = ttMove; // Can be MOVE_NONE
+ ss->bestMove = ttMove; // Can be MOVE_NONE
return value_from_tt(tte->value(), ply);
}
- // Step 5. Evaluate the position statically
- // At PV nodes we do this only to update gain statistics
+ // Step 5. Evaluate the position statically and
+ // update gain statistics of parent move.
isCheck = pos.is_check();
- if (!isCheck)
+ if (isCheck)
+ ss->eval = evalMargin = VALUE_NONE;
+ else if (tte)
{
- if (tte && tte->static_value() != VALUE_NONE)
- {
- ss->eval = tte->static_value();
- ei.kingDanger[pos.side_to_move()] = tte->king_danger();
- }
- else
- ss->eval = evaluate(pos, ei);
+ assert(tte->static_value() != VALUE_NONE);
- refinedValue = refine_eval(tte, ss->eval, ply); // Enhance accuracy with TT value if possible
- update_gains(pos, (ss-1)->currentMove, (ss-1)->eval, ss->eval);
+ ss->eval = tte->static_value();
+ evalMargin = tte->static_value_margin();
+ refinedValue = refine_eval(tte, ss->eval, ply);
+ }
+ else
+ {
+ refinedValue = ss->eval = evaluate(pos, evalMargin);
+ TT.store(posKey, VALUE_NONE, VALUE_TYPE_NONE, DEPTH_NONE, MOVE_NONE, ss->eval, evalMargin);
}
+ // Save gain for the parent non-capture move
+ update_gains(pos, (ss-1)->currentMove, (ss-1)->eval, ss->eval);
+
// Step 6. Razoring (is omitted in PV nodes)
if ( !PvNode
&& depth < RazorDepth
&& !value_is_mate(beta)
&& !pos.has_pawn_on_7th(pos.side_to_move()))
{
- // Pass ss->eval to qsearch() and avoid an evaluate call
- if (!tte || tte->static_value() == VALUE_NONE)
- TT.store(posKey, ss->eval, VALUE_TYPE_EXACT, Depth(-127*OnePly), MOVE_NONE, ss->eval, ei.kingDanger[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.
if ( !PvNode
&& !ss->skipNullMove
&& depth < RazorDepth
- && refinedValue >= beta + futility_margin(depth, 0)
&& !isCheck
+ && refinedValue >= beta + futility_margin(depth, 0)
&& !value_is_mate(beta)
&& pos.non_pawn_material(pos.side_to_move()))
return refinedValue - futility_margin(depth, 0);
// Step 8. Null move search with verification search (is omitted in PV nodes)
- // When we jump directly to qsearch() we do a null move only if static value is
- // at least beta. Otherwise we do a null move if static value is not more than
- // NullMoveMargin under beta.
if ( !PvNode
&& !ss->skipNullMove
- && depth > OnePly
- && refinedValue >= beta - (depth >= 4 * OnePly ? NullMoveMargin : 0)
+ && depth > ONE_PLY
&& !isCheck
+ && refinedValue >= beta
&& !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;
- // Do zugzwang verification search at high depths
- 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-5*OnePly, ply);
+ Value v = search<NonPV>(pos, ss, alpha, beta, depth-R*ONE_PLY, ply);
ss->skipNullMove = false;
if (v >= beta)
if (nullValue == value_mated_in(ply + 2))
mateThreat = true;
- ss->threatMove = (ss+1)->currentMove;
+ threatMove = (ss+1)->bestMove;
if ( depth < ThreatDepth
&& (ss-1)->reduction
- && connected_moves(pos, (ss-1)->currentMove, ss->threatMove))
+ && connected_moves(pos, (ss-1)->currentMove, threatMove))
return beta - 1;
}
}
&& 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);
// Expensive mate threat detection (only for PV nodes)
if (PvNode)
- mateThreat = pos.has_mate_threat(opposite_color(pos.side_to_move()));
+ mateThreat = pos.has_mate_threat();
// Initialize a MovePicker object for the current position
MovePicker mp = MovePicker(pos, ttMove, depth, H, ss, (PvNode ? -VALUE_INFINITE : beta));
CheckInfo ci(pos);
+ ss->bestMove = MOVE_NONE;
singleEvasion = isCheck && mp.number_of_evasions() == 1;
+ futilityBase = ss->eval + evalMargin;
singularExtensionNode = depth >= SingularExtensionDepth[PvNode]
- && tte && tte->move()
+ && tte
+ && tte->move()
&& !excludedMove // Do not allow recursive singular extension search
- && is_lower_bound(tte->type())
- && tte->depth() >= depth - 3 * OnePly;
+ && (tte->type() & VALUE_TYPE_LOWER)
+ && 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
while ( bestValue < beta
&& (move = mp.get_next_move()) != MOVE_NONE
- && !TM.thread_should_stop(threadID))
+ && !ThreadsMgr.thread_should_stop(threadID))
{
assert(move_is_ok(move));
// Step 11. Decide the new search depth
ext = extension<PvNode>(pos, move, captureOrPromotion, moveIsCheck, singleEvasion, mateThreat, &dangerous);
- // Singular extension search. We extend the TT move if its value is much better than
- // its siblings. To verify this we do a reduced search on all the other moves but the
- // ttMove, if result is lower then ttValue minus a margin then we extend ttMove.
+ // 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 is singular and should be extended.
+ // To verify this we do a reduced search on all the other moves but the ttMove, if result is
+ // lower then ttValue minus a margin then we extend ttMove.
if ( singularExtensionNode
&& move == tte->move()
- && ext < OnePly)
+ && ext < ONE_PLY)
{
Value ttValue = value_from_tt(tte->value(), ply);
Value v = search<NonPV>(pos, ss, b - 1, b, depth / 2, ply);
ss->skipNullMove = false;
ss->excludedMove = MOVE_NONE;
- if (v < ttValue - SingularExtensionMargin)
- ext = OnePly;
+ ss->bestMove = MOVE_NONE;
+ if (v < b)
+ 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;
{
// Move count based pruning
if ( moveCount >= futility_move_count(depth)
- && !(ss->threatMove && connected_threat(pos, move, ss->threatMove))
+ && !(threatMove && connected_threat(pos, move, threatMove))
&& bestValue > value_mated_in(PLY_MAX))
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)
+ futilityValueScaled = futilityBase + futility_margin(predictedDepth, moveCount)
+ H.gain(pos.piece_on(move_from(move)), move_to(move));
if (futilityValueScaled < beta)
// 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);
}
}
bestValue = value;
if (value > alpha)
{
- if (PvNode && value < beta) // This guarantees that always: alpha < beta
+ if (PvNode && value < beta) // We want always alpha < beta
alpha = value;
if (value == value_mate_in(ply + 1))
// Step 18. Check for split
if ( depth >= MinimumSplitDepth
- && TM.active_threads() > 1
+ && ThreadsMgr.active_threads() > 1
&& bestValue < beta
- && TM.available_thread_exists(threadID)
+ && ThreadsMgr.available_thread_exists(threadID)
&& !AbortSearch
- && !TM.thread_should_stop(threadID)
+ && !ThreadsMgr.thread_should_stop(threadID)
&& Iteration <= 99)
- TM.split<FakeSplit>(pos, ss, ply, &alpha, beta, &bestValue, depth,
- mateThreat, &moveCount, &mp, PvNode);
+ ThreadsMgr.split<FakeSplit>(pos, ss, ply, &alpha, beta, &bestValue, depth,
+ threatMove, mateThreat, &moveCount, &mp, PvNode);
}
// Step 19. Check for mate and stalemate
// no legal moves, it must be mate or stalemate.
// If one move was excluded return fail low score.
if (!moveCount)
- return excludedMove ? oldAlpha : (isCheck ? value_mated_in(ply) : VALUE_DRAW);
+ return excludedMove ? oldAlpha : isCheck ? value_mated_in(ply) : VALUE_DRAW;
// Step 20. Update tables
// If the search is not aborted, update the transposition table,
// history counters, and killer moves.
- if (AbortSearch || TM.thread_should_stop(threadID))
+ if (AbortSearch || ThreadsMgr.thread_should_stop(threadID))
return bestValue;
- ValueType f = (bestValue <= oldAlpha ? VALUE_TYPE_UPPER : bestValue >= beta ? VALUE_TYPE_LOWER : VALUE_TYPE_EXACT);
+ ValueType vt = (bestValue <= oldAlpha ? VALUE_TYPE_UPPER : bestValue >= beta ? VALUE_TYPE_LOWER : VALUE_TYPE_EXACT);
move = (bestValue <= oldAlpha ? MOVE_NONE : ss->bestMove);
- TT.store(posKey, value_to_tt(bestValue, ply), f, depth, move, ss->eval, ei.kingDanger[pos.side_to_move()]);
+ TT.store(posKey, value_to_tt(bestValue, ply), vt, depth, move, ss->eval, evalMargin);
// Update killers and history only for non capture moves that fails high
- if (bestValue >= beta)
+ if ( bestValue >= beta
+ && !pos.move_is_capture_or_promotion(move))
{
- TM.incrementBetaCounter(pos.side_to_move(), depth, threadID);
- if (!pos.move_is_capture_or_promotion(move))
- {
update_history(pos, move, depth, movesSearched, moveCount);
update_killers(move, ss);
- }
}
assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);
// 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) {
assert(PvNode || alpha == beta - 1);
assert(depth <= 0);
assert(ply > 0 && ply < PLY_MAX);
- assert(pos.thread() >= 0 && pos.thread() < TM.active_threads());
+ assert(pos.thread() >= 0 && pos.thread() < ThreadsMgr.active_threads());
- EvalInfo ei;
StateInfo st;
Move ttMove, move;
- Value bestValue, value, futilityValue, futilityBase;
+ Value bestValue, value, evalMargin, futilityValue, futilityBase;
bool isCheck, deepChecks, enoughMaterial, moveIsCheck, evasionPrunable;
const TTEntry* tte;
Value oldAlpha = alpha;
- TM.incrementNodeCounter(pos.thread());
+ ThreadsMgr.incrementNodeCounter(pos.thread());
ss->bestMove = ss->currentMove = MOVE_NONE;
- ss->eval = VALUE_NONE;
// Check for an instant draw or maximum ply reached
if (pos.is_draw() || ply >= PLY_MAX - 1)
if (!PvNode && tte && ok_to_use_TT(tte, depth, beta, ply))
{
- ss->currentMove = ttMove; // Can be MOVE_NONE
+ ss->bestMove = ttMove; // Can be MOVE_NONE
return value_from_tt(tte->value(), ply);
}
if (isCheck)
{
bestValue = futilityBase = -VALUE_INFINITE;
+ ss->eval = evalMargin = VALUE_NONE;
deepChecks = enoughMaterial = false;
}
else
{
- if (tte && tte->static_value() != VALUE_NONE)
+ if (tte)
{
- ei.kingDanger[pos.side_to_move()] = tte->king_danger();
+ assert(tte->static_value() != VALUE_NONE);
+
+ evalMargin = tte->static_value_margin();
bestValue = tte->static_value();
}
else
- bestValue = evaluate(pos, ei);
+ bestValue = evaluate(pos, evalMargin);
ss->eval = bestValue;
update_gains(pos, (ss-1)->currentMove, (ss-1)->eval, ss->eval);
if (bestValue >= beta)
{
if (!tte)
- TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_LOWER, Depth(-127*OnePly), MOVE_NONE, ss->eval, ei.kingDanger[pos.side_to_move()]);
+ TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_LOWER, DEPTH_NONE, MOVE_NONE, ss->eval, evalMargin);
return bestValue;
}
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()];
+ futilityBase = bestValue + FutilityMarginQS + evalMargin;
enoughMaterial = pos.non_pawn_material(pos.side_to_move()) > RookValueMidgame;
}
// 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)
{
evasionPrunable = isCheck
&& bestValue > value_mated_in(PLY_MAX)
&& !pos.move_is_capture(move)
- && pos.type_of_piece_on(move_from(move)) != KING
&& !pos.can_castle(pos.side_to_move());
// Don't search moves with negative SEE values
// 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));
- ValueType f = (bestValue <= oldAlpha ? VALUE_TYPE_UPPER : bestValue >= beta ? VALUE_TYPE_LOWER : VALUE_TYPE_EXACT);
- TT.store(pos.get_key(), value_to_tt(bestValue, ply), f, d, ss->bestMove, ss->eval, ei.kingDanger[pos.side_to_move()]);
-
- // Update killers only for checking moves that fails high
- if ( bestValue >= beta
- && !pos.move_is_capture_or_promotion(ss->bestMove))
- update_killers(ss->bestMove, ss);
+ 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, evalMargin);
assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);
template <NodeType PvNode>
void sp_search(SplitPoint* sp, int threadID) {
- assert(threadID >= 0 && threadID < TM.active_threads());
- assert(TM.active_threads() > 1);
+ assert(threadID >= 0 && threadID < ThreadsMgr.active_threads());
+ assert(ThreadsMgr.active_threads() > 1);
StateInfo st;
Move move;
while ( sp->bestValue < sp->beta
&& (move = sp->mp->get_next_move()) != MOVE_NONE
- && !TM.thread_should_stop(threadID))
+ && !ThreadsMgr.thread_should_stop(threadID))
{
moveCount = ++sp->moveCount;
lock_release(&(sp->lock));
// 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;
{
// Move count based pruning
if ( moveCount >= futility_move_count(sp->depth)
- && !(ss->threatMove && connected_threat(pos, move, ss->threatMove))
+ && !(sp->threatMove && connected_threat(pos, move, sp->threatMove))
&& sp->bestValue > value_mated_in(PLY_MAX))
{
lock_grab(&(sp->lock));
{
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
// Step 17. Check for new best move
lock_grab(&(sp->lock));
- if (value > sp->bestValue && !TM.thread_should_stop(threadID))
+ if (value > sp->bestValue && !ThreadsMgr.thread_should_stop(threadID))
{
sp->bestValue = value;
}
- // value_is_mate() checks if the given value is a mate one
- // eventually compensated for the ply.
+ // value_is_mate() checks if the given value is a mate one eventually
+ // compensated for the ply.
bool value_is_mate(Value value) {
}
- // move_is_killer() checks if the given move is among the
- // killer moves of that ply.
+ // value_to_tt() adjusts a mate score from "plies to mate from the root" to
+ // "plies to mate from the current ply". Non-mate scores are unchanged.
+ // The function is called before storing a value to the transposition table.
+
+ Value value_to_tt(Value v, int ply) {
+
+ if (v >= value_mate_in(PLY_MAX))
+ return v + ply;
+
+ if (v <= value_mated_in(PLY_MAX))
+ return v - ply;
+
+ return v;
+ }
+
+
+ // value_from_tt() is the inverse of value_to_tt(): It adjusts a mate score from
+ // the transposition table to a mate score corrected for the current ply.
+
+ Value value_from_tt(Value v, int ply) {
+
+ if (v >= value_mate_in(PLY_MAX))
+ return v - ply;
+
+ if (v <= value_mated_in(PLY_MAX))
+ return v + ply;
+
+ return v;
+ }
+
+
+ // move_is_killer() checks if the given move is among the killer moves
bool move_is_killer(Move m, SearchStack* ss) {
- const Move* k = ss->killers;
- for (int i = 0; i < KILLER_MAX; i++, k++)
- if (*k == m)
- return true;
+ if (ss->killers[0] == m || ss->killers[1] == m)
+ return true;
return false;
}
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);
}
|| v >= Max(value_mate_in(PLY_MAX), beta)
|| v < Min(value_mated_in(PLY_MAX), beta))
- && ( (is_lower_bound(tte->type()) && v >= beta)
- || (is_upper_bound(tte->type()) && v < beta));
+ && ( ((tte->type() & VALUE_TYPE_LOWER) && v >= beta)
+ || ((tte->type() & VALUE_TYPE_UPPER) && v < beta));
}
Value refine_eval(const TTEntry* tte, Value defaultEval, int ply) {
- if (!tte)
- return defaultEval;
+ assert(tte);
Value v = value_from_tt(tte->value(), ply);
- if ( (is_lower_bound(tte->type()) && v >= defaultEval)
- || (is_upper_bound(tte->type()) && v < defaultEval))
+ if ( ((tte->type() & VALUE_TYPE_LOWER) && v >= defaultEval)
+ || ((tte->type() & VALUE_TYPE_UPPER) && v < defaultEval))
return v;
return defaultEval;
if (m == ss->killers[0])
return;
- for (int i = KILLER_MAX - 1; i > 0; i--)
- ss->killers[i] = ss->killers[i - 1];
-
+ ss->killers[1] = ss->killers[0];
ss->killers[0] = m;
}
if ( m != MOVE_NULL
&& before != VALUE_NONE
&& after != VALUE_NONE
- && pos.captured_piece() == NO_PIECE_TYPE
- && !move_is_castle(m)
- && !move_is_promotion(m))
+ && pos.captured_piece_type() == PIECE_TYPE_NONE
+ && !move_is_special(m))
H.set_gain(pos.piece_on(move_to(m)), move_to(m), -(before + after));
}
}
+ // value_to_uci() converts a value to a string suitable for use with the UCI protocol
+
+ std::string value_to_uci(Value v) {
+
+ std::stringstream s;
+
+ 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 );
+
+ return s.str();
+ }
+
// nps() computes the current nodes/second count.
int nps() {
int t = current_search_time();
- return (t > 0 ? int((TM.nodes_searched() * 1000) / t) : 0);
+ return (t > 0 ? int((ThreadsMgr.nodes_searched() * 1000) / t) : 0);
}
if (dbg_show_hit_rate)
dbg_print_hit_rate();
- cout << "info nodes " << TM.nodes_searched() << " nps " << nps()
- << " time " << t << " hashfull " << TT.full() << endl;
+ cout << "info nodes " << ThreadsMgr.nodes_searched() << " nps " << nps()
+ << " time " << t << endl;
}
// Should we stop the search?
bool stillAtFirstMove = FirstRootMove
&& !AspirationFailLow
- && t > MaxSearchTime + ExtraSearchTime;
+ && t > TimeMgr.available_time();
- bool noMoreTime = t > AbsoluteMaxSearchTime
+ bool noMoreTime = t > TimeMgr.maximum_time()
|| stillAtFirstMove;
if ( (Iteration >= 3 && UseTimeManagement && noMoreTime)
|| (ExactMaxTime && t >= ExactMaxTime)
- || (Iteration >= 3 && MaxNodes && TM.nodes_searched() >= MaxNodes))
+ || (Iteration >= 3 && MaxNodes && ThreadsMgr.nodes_searched() >= MaxNodes))
AbortSearch = true;
}
bool stillAtFirstMove = FirstRootMove
&& !AspirationFailLow
- && t > MaxSearchTime + ExtraSearchTime;
+ && t > TimeMgr.available_time();
- bool noMoreTime = t > AbsoluteMaxSearchTime
+ bool noMoreTime = t > TimeMgr.maximum_time()
|| stillAtFirstMove;
if (Iteration >= 3 && UseTimeManagement && (noMoreTime || StopOnPonderhit))
{
ss->excludedMove = MOVE_NONE;
ss->skipNullMove = false;
+ ss->reduction = DEPTH_ZERO;
if (i < 3)
- {
- ss->init();
- ss->initKillers();
- }
+ ss->killers[0] = ss->killers[1] = ss->mateKiller = MOVE_NONE;
}
}
void print_pv_info(const Position& pos, Move pv[], Value alpha, Value beta, Value value) {
cout << "info depth " << Iteration
- << " score " << value_to_string(value)
+ << " score " << value_to_uci(value)
<< (value >= beta ? " lowerbound" : value <= alpha ? " upperbound" : "")
<< " time " << current_search_time()
- << " nodes " << TM.nodes_searched()
+ << " nodes " << ThreadsMgr.nodes_searched()
<< " nps " << nps()
<< " pv ";
value <= alpha ? VALUE_TYPE_UPPER : VALUE_TYPE_EXACT;
LogFile << pretty_pv(pos, current_search_time(), Iteration,
- TM.nodes_searched(), value, t, pv) << endl;
+ ThreadsMgr.nodes_searched(), value, t, pv) << endl;
}
}
+ // insert_pv_in_tt() is called at the end of a search iteration, and inserts
+ // the PV back into the TT. This makes sure the old PV moves are searched
+ // first, even if the old TT entries have been overwritten.
+
+ void insert_pv_in_tt(const Position& pos, Move pv[]) {
+
+ StateInfo st;
+ TTEntry* tte;
+ Position p(pos, pos.thread());
+ Value v, m = VALUE_NONE;
+
+ for (int i = 0; pv[i] != MOVE_NONE; i++)
+ {
+ tte = TT.retrieve(p.get_key());
+ if (!tte || tte->move() != pv[i])
+ {
+ v = (p.is_check() ? VALUE_NONE : evaluate(p, m));
+ TT.store(p.get_key(), VALUE_NONE, VALUE_TYPE_NONE, DEPTH_NONE, pv[i], v, m);
+ }
+ p.do_move(pv[i], st);
+ }
+ }
+
+
+ // extract_pv_from_tt() builds a PV by adding moves from the transposition table.
+ // We consider also failing high nodes and not only VALUE_TYPE_EXACT nodes. This
+ // allow to always have a ponder move even when we fail high at root and also a
+ // long PV to print that is important for position analysis.
+
+ void extract_pv_from_tt(const Position& pos, Move bestMove, Move pv[]) {
+
+ StateInfo st;
+ TTEntry* tte;
+ Position p(pos, pos.thread());
+ int ply = 0;
+
+ assert(bestMove != MOVE_NONE);
+
+ pv[ply] = bestMove;
+ p.do_move(pv[ply++], st);
+
+ while ( (tte = TT.retrieve(p.get_key())) != NULL
+ && tte->move() != MOVE_NONE
+ && move_is_legal(p, tte->move())
+ && ply < PLY_MAX
+ && (!p.is_draw() || ply < 2))
+ {
+ pv[ply] = tte->move();
+ p.do_move(pv[ply++], st);
+ }
+ pv[ply] = MOVE_NONE;
+ }
+
+
// init_thread() is the function which is called when a new thread is
// launched. It simply calls the idle_loop() function with the supplied
// threadID. There are two versions of this function; one for POSIX
void* init_thread(void *threadID) {
- TM.idle_loop(*(int*)threadID, NULL);
+ ThreadsMgr.idle_loop(*(int*)threadID, NULL);
return NULL;
}
DWORD WINAPI init_thread(LPVOID threadID) {
- TM.idle_loop(*(int*)threadID, NULL);
+ ThreadsMgr.idle_loop(*(int*)threadID, NULL);
return 0;
}
threads[i].nodes = 0ULL;
}
- void ThreadsManager::resetBetaCounters() {
-
- for (int i = 0; i < MAX_THREADS; i++)
- threads[i].betaCutOffs[WHITE] = threads[i].betaCutOffs[BLACK] = 0ULL;
- }
-
int64_t ThreadsManager::nodes_searched() const {
int64_t result = 0ULL;
return result;
}
- void ThreadsManager::get_beta_counters(Color us, int64_t& our, int64_t& their) const {
-
- our = their = 0UL;
- for (int i = 0; i < MAX_THREADS; i++)
- {
- our += threads[i].betaCutOffs[us];
- their += threads[i].betaCutOffs[opposite_color(us)];
- }
- }
-
// idle_loop() is where the threads are parked when they have no work to do.
// The parameter 'sp', if non-NULL, is a pointer to an active SplitPoint
#endif
// Initialize global locks
- lock_init(&MPLock, NULL);
- lock_init(&WaitLock, NULL);
+ lock_init(&MPLock);
+ lock_init(&WaitLock);
#if !defined(_MSC_VER)
pthread_cond_init(&WaitCond, NULL);
// Initialize splitPoints[] locks
for (i = 0; i < MAX_THREADS; i++)
for (int j = 0; j < MAX_ACTIVE_SPLIT_POINTS; j++)
- lock_init(&(threads[i].splitPoints[j].lock), NULL);
+ lock_init(&(threads[i].splitPoints[j].lock));
// Will be set just before program exits to properly end the threads
AllThreadsShouldExit = false;
template <bool Fake>
void ThreadsManager::split(const Position& p, SearchStack* ss, int ply, Value* alpha,
- const Value beta, Value* bestValue, Depth depth, bool mateThreat,
- int* moveCount, MovePicker* mp, bool pvNode) {
+ const Value beta, Value* bestValue, Depth depth, Move threatMove,
+ bool mateThreat, int* moveCount, MovePicker* mp, bool pvNode) {
assert(p.is_ok());
assert(ply > 0 && ply < PLY_MAX);
assert(*bestValue >= -VALUE_INFINITE);
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);
splitPoint.stopRequest = false;
splitPoint.ply = ply;
splitPoint.depth = depth;
+ splitPoint.threatMove = threatMove;
splitPoint.mateThreat = mateThreat;
splitPoint.alpha = *alpha;
splitPoint.beta = beta;
// RootMoveList c'tor
- RootMoveList::RootMoveList(Position& pos, Move searchMoves[]) : count(0) {
+ RootMoveList::RootMoveList(Position& pos, Move searchMoves[]) {
SearchStack ss[PLY_MAX_PLUS_2];
- MoveStack mlist[MaxRootMoves];
+ MoveStack mlist[MOVES_MAX];
StateInfo st;
bool includeAllMoves = (searchMoves[0] == MOVE_NONE);
+ // Initialize search stack
+ init_ss_array(ss, PLY_MAX_PLUS_2);
+ ss[0].eval = VALUE_NONE;
+ count = 0;
+
// Generate all legal moves
MoveStack* last = generate_moves(pos, mlist);
continue;
// Find a quick score for the move
- init_ss_array(ss, PLY_MAX_PLUS_2);
- pos.do_move(cur->move, st);
- moves[count].move = cur->move;
- moves[count].score = -qsearch<PV>(pos, ss+1, -VALUE_INFINITE, VALUE_INFINITE, Depth(0), 1);
- moves[count].pv[0] = cur->move;
+ moves[count].move = ss[0].currentMove = moves[count].pv[0] = cur->move;
moves[count].pv[1] = MOVE_NONE;
+ pos.do_move(cur->move, st);
+ moves[count].score = -qsearch<PV>(pos, ss+1, -VALUE_INFINITE, VALUE_INFINITE, DEPTH_ZERO, 1);
pos.undo_move(cur->move);
count++;
}
sort();
}
+ // Score root moves using the standard way used in main search, the moves
+ // are scored according to the order in which are returned by MovePicker.
- // RootMoveList simple methods definitions
-
- void RootMoveList::set_move_nodes(int moveNum, int64_t nodes) {
+ void RootMoveList::score_moves(const Position& pos)
+ {
+ Move move;
+ int score = 1000;
+ MovePicker mp = MovePicker(pos, MOVE_NONE, ONE_PLY, H);
- moves[moveNum].nodes = nodes;
- moves[moveNum].cumulativeNodes += nodes;
+ while ((move = mp.get_next_move()) != MOVE_NONE)
+ for (int i = 0; i < count; i++)
+ if (moves[i].move == move)
+ {
+ moves[i].mp_score = score--;
+ break;
+ }
}
- void RootMoveList::set_beta_counters(int moveNum, int64_t our, int64_t their) {
-
- moves[moveNum].ourBeta = our;
- moves[moveNum].theirBeta = their;
- }
+ // RootMoveList simple methods definitions
void RootMoveList::set_move_pv(int moveNum, const Move pv[]) {
}
}
-} // namspace
+} // namespace
projects / stockfish / blobdiff