Thread threads[MAX_THREADS];
SplitPoint SplitPointStack[MAX_THREADS][ACTIVE_SPLIT_POINTS_MAX];
- Lock MPLock;
+ Lock MPLock, WaitLock;
#if !defined(_MSC_VER)
pthread_cond_t WaitCond;
- pthread_mutex_t WaitLock;
#else
HANDLE SitIdleEvent[MAX_THREADS];
#endif
// Step 6. Razoring
+ // Maximum depth for razoring
const Depth RazorDepth = 4 * OnePly;
+
+ // Dynamic razoring margin based on depth
inline Value razor_margin(Depth d) { return Value(0x200 + 0x10 * d); }
// Step 8. Null move search with verification search
// 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;
+
// Step 9. Internal iterative deepening
+ // Minimum depth for use of internal iterative deepening
const Depth IIDDepthAtPVNodes = 5 * OnePly;
const Depth IIDDepthAtNonPVNodes = 8 * OnePly;
Depth CheckExtension[2], SingleEvasionExtension[2], PawnPushTo7thExtension[2];
Depth PassedPawnExtension[2], PawnEndgameExtension[2], MateThreatExtension[2];
+ // Minimum depth for use of singular extension
const Depth SingularExtensionDepthAtPVNodes = 6 * OnePly;
const Depth SingularExtensionDepthAtNonPVNodes = 8 * OnePly;
// remaining ones we will extend it.
const Value SingularExtensionMargin = Value(0x20);
+ // Step 12. Futility pruning
+ // Futility margin for quiescence search
+ const Value FutilityMarginQS = Value(0x80);
- // Search depth at iteration 1
- const Depth InitialDepth = OnePly;
+ // Futility lookup tables (initialized at startup) and their getter functions
+ int32_t FutilityMarginsMatrix[14][64]; // [depth][moveNumber]
+ int FutilityMoveCountArray[32]; // [depth]
- // Easy move margin. An easy move candidate must be at least this much
- // better than the second best move.
- const Value EasyMoveMargin = Value(0x200);
+ inline Value futility_margin(Depth d, int mn) { return Value(d < 7*OnePly ? FutilityMarginsMatrix[Max(d, 0)][Min(mn, 63)] : 2 * VALUE_INFINITE); }
+ inline int futility_move_count(Depth d) { return d < 16*OnePly ? FutilityMoveCountArray[d] : 512; }
- /// Lookup tables initialized at startup
+ // Step 14. Reduced search
- // Reduction lookup tables and their getter functions
+ // Reduction lookup tables (initialized at startup) and their getter functions
int8_t PVReductionMatrix[64][64]; // [depth][moveNumber]
int8_t NonPVReductionMatrix[64][64]; // [depth][moveNumber]
inline Depth pv_reduction(Depth d, int mn) { return (Depth) PVReductionMatrix[Min(d / 2, 63)][Min(mn, 63)]; }
inline Depth nonpv_reduction(Depth d, int mn) { return (Depth) NonPVReductionMatrix[Min(d / 2, 63)][Min(mn, 63)]; }
- // Futility lookup tables and their getter functions
- const Value FutilityMarginQS = Value(0x80);
- int32_t FutilityMarginsMatrix[14][64]; // [depth][moveNumber]
- int FutilityMoveCountArray[32]; // [depth]
+ // Step. Common adjustments
- inline Value futility_margin(Depth d, int mn) { return Value(d < 7*OnePly ? FutilityMarginsMatrix[Max(d, 0)][Min(mn, 63)] : 2 * VALUE_INFINITE); }
- inline int futility_move_count(Depth d) { return d < 16*OnePly ? FutilityMoveCountArray[d] : 512; }
-
- /// Variables initialized by UCI options
+ // Search depth at iteration 1
+ const Depth InitialDepth = OnePly;
- // Depth limit for use of dynamic threat detection
- Depth ThreatDepth;
+ // 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 Value LSNValue = value_from_centipawns(200);
bool loseOnTime = false;
+
+ /// Global variables
+
// Iteration counters
int Iteration;
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)"));
- ThreatDepth = get_option_value_int("Threat Depth") * OnePly;
-
Chess960 = get_option_value_bool("UCI_Chess960");
ShowCurrentLine = get_option_value_bool("UCI_ShowCurrLine");
UseLogFile = get_option_value_bool("Use Search Log");
// Loop through all legal moves until no moves remain or a beta cutoff occurs
// Initialize a MovePicker object for the current position
- MovePicker mp = MovePicker(pos, ttMove, depth, H, &ss[ply]);
+ MovePicker mp = MovePicker(pos, ttMove, depth, H, &ss[ply], beta);
CheckInfo ci(pos);
while ( bestValue < beta
continue;
// Value based pruning
- Depth predictedDepth = newDepth - nonpv_reduction(depth, moveCount); //FIXME: We are ignoring condition: depth >= 3*OnePly, BUG??
+ Depth predictedDepth = newDepth - nonpv_reduction(depth, moveCount); // We illogically ignore reduction condition depth >= 3*OnePly
futilityValueScaled = ss[ply].eval + futility_margin(predictedDepth, moveCount)
+ H.gain(pos.piece_on(move_from(move)), move_to(move)) + 45;
DWORD WINAPI init_thread(LPVOID threadID) {
TM.idle_loop(*(int*)threadID, NULL);
- return NULL;
+ return 0;
}
#endif
threads[threadID].state = THREAD_SLEEPING;
#if !defined(_MSC_VER)
- pthread_mutex_lock(&WaitLock);
+ lock_grab(&WaitLock);
if (AllThreadsShouldSleep || threadID >= ActiveThreads)
pthread_cond_wait(&WaitCond, &WaitLock);
- pthread_mutex_unlock(&WaitLock);
+ lock_release(&WaitLock);
#else
WaitForSingleObject(SitIdleEvent[threadID], INFINITE);
#endif
// Initialize global locks
lock_init(&MPLock, NULL);
+ lock_init(&WaitLock, NULL);
+
+#if !defined(_MSC_VER)
+ pthread_cond_init(&WaitCond, NULL);
+#else
+ for (i = 0; i < MAX_THREADS; i++)
+ SitIdleEvent[i] = CreateEvent(0, FALSE, FALSE, 0);
+#endif
// Initialize SplitPointStack locks
for (i = 0; i < MAX_THREADS; i++)
lock_init(&(SplitPointStack[i][j].lock), NULL);
}
-#if !defined(_MSC_VER)
- pthread_mutex_init(&WaitLock, NULL);
- pthread_cond_init(&WaitCond, NULL);
-#else
- for (i = 0; i < MAX_THREADS; i++)
- SitIdleEvent[i] = CreateEvent(0, FALSE, FALSE, 0);
-#endif
-
// Will be set just before program exits to properly end the threads
AllThreadsShouldExit = false;
#if !defined(_MSC_VER)
ok = (pthread_create(pthread, NULL, init_thread, (void*)(&i)) == 0);
#else
- DWORD iID[1];
- ok = (CreateThread(NULL, 0, init_thread, (LPVOID)(&i), 0, iID) != NULL);
+ ok = (CreateThread(NULL, 0, init_thread, (LPVOID)(&i), 0, NULL) != NULL);
#endif
if (!ok)
for (int i = 0; i < MAX_THREADS; i++)
for (int j = 0; j < ACTIVE_SPLIT_POINTS_MAX; j++)
lock_destroy(&(SplitPointStack[i][j].lock));
+
+ lock_destroy(&WaitLock);
+ lock_destroy(&MPLock);
}
if (ActiveThreads == 1)
return;
- for (int i = 1; i < ActiveThreads; i++)
- assert(threads[i].state == THREAD_SLEEPING);
-
#if !defined(_MSC_VER)
pthread_mutex_lock(&WaitLock);
pthread_cond_broadcast(&WaitCond);