static void note_quiet_moves(list_t * list, const board_t * board, bool in_pv, int ThreadId) {
int size;
int i, move;
int move_piece;
ASSERT(list_is_ok(list));
ASSERT(board!=NULL);
size = LIST_SIZE(list);
if (size >= 2) {
for (i = 0; i < size; i++) {
move = LIST_MOVE(list,i);
list->value[i] = quiet_move_value(move,board,ThreadId);
if (TryQuietKingAttacks && in_pv) {
move_piece = MOVE_PIECE(move,board);
if (!(PIECE_IS_PAWN(move_piece) || PIECE_IS_KING(move_piece))) {
if (narrow_piece_attack_king(board,move_piece,MOVE_TO(move),KING_POS(board,COLOUR_OPP(board->turn)))) {
if (see_move(move,board) >= 0) {
// if (1 == NumberThreadsInternal) print_board(board);
list->value[i] += 16;
}
}
}
}
}
}
}
void list_filter(list_t * list, board_t * board, move_test_t test, bool keep) {
int pos;
int i, move, value;
ASSERT(list!=NULL);
ASSERT(board!=NULL);
ASSERT(test!=NULL);
ASSERT(keep==true||keep==false);
pos = 0;
for (i = 0; i < LIST_SIZE(list); i++) {
ASSERT(pos>=0&&pos<=i);
move = LIST_MOVE(list,i);
value = LIST_VALUE(list,i);
if ((*test)(move,board) == keep) {
list->move[pos] = move;
list->value[pos] = value;
pos++;
}
}
ASSERT(pos>=0&&pos<=LIST_SIZE(list));
list->size = pos;
// debug
ASSERT(list_is_ok(list));
}
static void note_mvv_lva(list_t * list, const board_t * board) {
int size;
int i, move;
ASSERT(list_is_ok(list));
ASSERT(board!=NULL);
size = LIST_SIZE(list);
if (size >= 2) {
for (i = 0; i < size; i++) {
move = LIST_MOVE(list,i);
list->value[i] = mvv_lva(move,board);
}
}
}
static void note_moves_simple(list_t * list, const board_t * board, int trans_killer) {
int size;
int i, move;
ASSERT(list_is_ok(list));
ASSERT(board!=NULL);
ASSERT(trans_killer==MoveNone||move_is_ok(trans_killer));
size = LIST_SIZE(list);
if (size >= 2) {
for (i = 0; i < size; i++) {
move = LIST_MOVE(list,i);
list->value[i] = move_value_simple(move,board,trans_killer);
}
}
}
void note_moves(list_t * list, const board_t * board, int height, int trans_killer, int ThreadId) {
int size;
int i, move;
ASSERT(list_is_ok(list));
ASSERT(board!=NULL);
ASSERT(height_is_ok(height));
ASSERT(trans_killer==MoveNone||move_is_ok(trans_killer));
size = LIST_SIZE(list);
if (size >= 2) {
for (i = 0; i < size; i++) {
move = LIST_MOVE(list,i);
list->value[i] = move_value(move,board,height,trans_killer,ThreadId);
}
}
}
bool board_is_stalemate(board_t * board) {
list_t list[1];
int i, move;
ASSERT(board!=NULL);
// init
if (IS_IN_CHECK(board,board->turn)) return false; // in check => not stalemate
// move loop
gen_moves(list,board);
for (i = 0; i < LIST_SIZE(list); i++) {
move = LIST_MOVE(list,i);
if (pseudo_is_legal(move,board)) return false; // legal move => not stalemate
}
return true; // in check and no legal move => mate
}
int sort_next_qs(sort_t * sort) {
int move;
int gen;
ASSERT(sort!=NULL);
while (true) {
while (sort->pos < LIST_SIZE(sort->list)) {
// next move
move = LIST_MOVE(sort->list,sort->pos);
sort->pos++;
ASSERT(move!=MoveNone);
// test
if (false) {
} else if (sort->test == TEST_LEGAL) {
if (!pseudo_is_legal(move,sort->board)) continue;
} else if (sort->test == TEST_CAPTURE_QS) {
ASSERT(move_is_tactical(move,sort->board));
if (!capture_is_good(move,sort->board,false)) continue;
if (!pseudo_is_legal(move,sort->board)) continue;
} else if (sort->test == TEST_CHECK_QS) {
ASSERT(!move_is_tactical(move,sort->board));
ASSERT(move_is_check(move,sort->board));
if (see_move(move,sort->board) < 0) continue;
if (!pseudo_is_legal(move,sort->board)) continue;
} else {
ASSERT(false);
return MoveNone;
}
ASSERT(pseudo_is_legal(move,sort->board));
return move;
}
// next stage
gen = Code[sort->gen++];
if (false) {
} else if (gen == GEN_EVASION_QS) {
gen_pseudo_evasions(sort->list,sort->board,sort->attack);
note_moves_simple(sort->list,sort->board);
list_sort(sort->list);
sort->test = TEST_LEGAL;
} else if (gen == GEN_CAPTURE_QS) {
gen_captures(sort->list,sort->board);
note_mvv_lva(sort->list,sort->board);
list_sort(sort->list);
sort->test = TEST_CAPTURE_QS;
} else if (gen == GEN_CHECK_QS) {
gen_quiet_checks(sort->list,sort->board);
sort->test = TEST_CHECK_QS;
} else {
ASSERT(gen==GEN_END);
return MoveNone;
}
sort->pos = 0;
}
}
int sort_next(sort_t * sort, int ThreadId) {
int move;
int gen;
ASSERT(sort!=NULL);
while (true) {
while (sort->pos < LIST_SIZE(sort->list)) {
// next move
move = LIST_MOVE(sort->list,sort->pos);
sort->value = HistoryMax; // default score, HistoryMax instead of 16384
sort->pos++;
ASSERT(move!=MoveNone);
// test
if (false) {
} else if (sort->test == TEST_NONE) {
// no-op
} else if (sort->test == TEST_TRANS_KILLER) {
if (!move_is_pseudo(move,sort->board)) continue;
if (!pseudo_is_legal(move,sort->board)) continue;
} else if (sort->test == TEST_GOOD_CAPTURE) {
ASSERT(move_is_tactical(move,sort->board));
if (move == sort->trans_killer) continue;
if (!capture_is_good(move,sort->board,sort->in_pv)) {
LIST_ADD(sort->bad,move);
continue;
}
if (!pseudo_is_legal(move,sort->board)) continue;
} else if (sort->test == TEST_BAD_CAPTURE) {
ASSERT(move_is_tactical(move,sort->board));
ASSERT(!capture_is_good(move,sort->board,sort->in_pv));
ASSERT(move!=sort->trans_killer);
if (!pseudo_is_legal(move,sort->board)) continue;
sort->value = HistoryBadCap; // WHM(31)
} else if (sort->test == TEST_KILLER) {
if (move == sort->trans_killer) continue;
if (!quiet_is_pseudo(move,sort->board)) continue;
if (!pseudo_is_legal(move,sort->board)) continue;
ASSERT(!move_is_tactical(move,sort->board));
sort->value = HistoryKiller; // WHM(31)
} else if (sort->test == TEST_QUIET) {
ASSERT(!move_is_tactical(move,sort->board));
if (move == sort->trans_killer) continue;
if (move == sort->killer_1) continue;
if (move == sort->killer_2) continue;
if (move == sort->killer_3) continue;
if (move == sort->killer_4) continue;
if (!pseudo_is_legal(move,sort->board)) continue;
sort->value = history_prob(move,sort->board,ThreadId);
} else {
ASSERT(false);
return MoveNone;
}
ASSERT(pseudo_is_legal(move,sort->board));
return move;
}
// next stage
gen = Code[sort->gen++];
if (false) {
} else if (gen == GEN_TRANS) {
LIST_CLEAR(sort->list);
if (sort->trans_killer != MoveNone) LIST_ADD(sort->list,sort->trans_killer);
sort->test = TEST_TRANS_KILLER;
} else if (gen == GEN_GOOD_CAPTURE) {
gen_captures(sort->list,sort->board);
note_mvv_lva(sort->list,sort->board);
list_sort(sort->list);
LIST_CLEAR(sort->bad);
sort->test = TEST_GOOD_CAPTURE;
} else if (gen == GEN_BAD_CAPTURE) {
list_copy(sort->list,sort->bad);
sort->test = TEST_BAD_CAPTURE;
} else if (gen == GEN_KILLER) {
LIST_CLEAR(sort->list);
if (sort->killer_1 != MoveNone) LIST_ADD(sort->list,sort->killer_1);
if (sort->killer_2 != MoveNone) LIST_ADD(sort->list,sort->killer_2);
if (sort->killer_3 != MoveNone) LIST_ADD(sort->list,sort->killer_3);
if (sort->killer_4 != MoveNone) LIST_ADD(sort->list,sort->killer_4);
sort->test = TEST_KILLER;
} else if (gen == GEN_QUIET) {
gen_quiet_moves(sort->list,sort->board);
note_quiet_moves(sort->list,sort->board,sort->in_pv,ThreadId);
list_sort(sort->list);
sort->test = TEST_QUIET;
} else {
ASSERT(gen==GEN_END);
return MoveNone;
}
sort->pos = 0;
}
}
int sort_next_qs(sort_t * sort) {
int move;
int gen;
ASSERT(sort!=NULL);
while (true) {
while (sort->pos < LIST_SIZE(sort->list)) {
// next move
move = LIST_MOVE(sort->list,sort->pos);
sort->pos++;
ASSERT(move!=MoveNone);
// test
if (false) {
} else if (sort->test == TEST_LEGAL) {
if (!pseudo_is_legal(move,sort->board)) continue;
} else if (sort->test == TEST_TRANS_KILLER) {
if (!move_is_pseudo(move,sort->board)) continue;
if (!pseudo_is_legal(move,sort->board)) continue;
// check
if (!MOVE_IS_TACTICAL(move,sort->board)
&& (!move_is_check(move,sort->board) || sort->depth < 0)) continue;
} else if (sort->test == TEST_CAPTURE_QS) {
ASSERT(MOVE_IS_TACTICAL(move,sort->board));
ASSERT(sort->value==NodePV||sort->value==NodeCut||sort->value==NodeAll);
if (move == sort->trans_killer) continue;
if (sort->value != NodePV && !capture_is_good(move,sort->board)) continue;
if (!pseudo_is_legal(move,sort->board)) continue;
} else if (sort->test == TEST_CHECK_QS) {
ASSERT(!MOVE_IS_TACTICAL(move,sort->board));
ASSERT(move_is_check(move,sort->board));
if (move == sort->trans_killer) continue;
if (see_move(move,sort->board,0) < 0) continue;
if (!pseudo_is_legal(move,sort->board)) continue;
} else {
ASSERT(false);
return MoveNone;
}
ASSERT(pseudo_is_legal(move,sort->board));
return move;
}
// next stage
gen = Code[sort->gen++];
if (false) {
} else if (gen == GEN_EVASION_QS) {
gen_pseudo_evasions(sort->list,sort->board,sort->attack);
note_moves_simple(sort->list,sort->board,sort->trans_killer);
list_sort(sort->list);
sort->test = TEST_LEGAL;
} else if (gen == GEN_TRANS) {
LIST_CLEAR(sort->list);
if (sort->trans_killer != MoveNone) LIST_ADD(sort->list,sort->trans_killer);
sort->test = TEST_TRANS_KILLER;
} else if (gen == GEN_CAPTURE_QS) {
gen_captures(sort->list,sort->board);
note_mvv_lva(sort->list,sort->board);
list_sort(sort->list);
sort->test = TEST_CAPTURE_QS;
} else if (gen == GEN_CHECK_QS) {
gen_quiet_checks(sort->list,sort->board);
sort->test = TEST_CHECK_QS;
} else {
ASSERT(gen==GEN_END);
return MoveNone;
}
sort->pos = 0;
}
}
int sort_next(sort_t * sort) {
int move;
int gen;
ASSERT(sort!=NULL);
while (true) {
while (sort->pos < LIST_SIZE(sort->list)) {
// next move
move = LIST_MOVE(sort->list,sort->pos);
sort->value = 65536; // default score
sort->pos++;
ASSERT(move!=MoveNone);
// test
if (false) {
} else if (sort->test == TEST_NONE) {
// Evasion (no-op)
} else if (sort->test == TEST_TRANS_KILLER) {
if (!move_is_pseudo(move,sort->board)) continue;
if (!pseudo_is_legal(move,sort->board)) continue;
} else if (sort->test == TEST_CAPTURE) {
ASSERT(MOVE_IS_TACTICAL(move,sort->board));
if (move == sort->trans_killer) continue;
if (!capture_is_good(move,sort->board)) {
LIST_ADD(sort->bad,move);
continue;
}
if (!pseudo_is_legal(move,sort->board)) continue;
} else if (sort->test == TEST_KILLER) {
if (move == sort->trans_killer) continue;
if (!quiet_is_pseudo(move,sort->board)) continue;
if (!pseudo_is_legal(move,sort->board)) continue;
ASSERT(!MOVE_IS_TACTICAL(move,sort->board));
sort->value = 32768;
} else if (sort->test == TEST_QUIET) {
ASSERT(!MOVE_IS_TACTICAL(move,sort->board));
if (move == sort->trans_killer) continue;
if (move == sort->killer_1) continue;
if (move == sort->killer_2) continue;
if (!pseudo_is_legal(move,sort->board)) continue;
sort->value = history_prob(move,sort->board);
} else if (sort->test == TEST_BAD) {
ASSERT(MOVE_IS_TACTICAL(move,sort->board));
ASSERT(!capture_is_good(move,sort->board));
ASSERT(move!=sort->trans_killer);
if (!pseudo_is_legal(move,sort->board)) continue;
} else {
ASSERT(false);
return MoveNone;
}
ASSERT(pseudo_is_legal(move,sort->board));
return move;
}
// next stage
gen = Code[sort->gen++];
if (false) {
} else if (gen == GEN_TRANS) {
LIST_CLEAR(sort->list);
if (sort->trans_killer != MoveNone) LIST_ADD(sort->list,sort->trans_killer);
sort->test = TEST_TRANS_KILLER;
} else if (gen == GEN_CAPTURE) {
gen_captures(sort->list,sort->board);
note_mvv_lva(sort->list,sort->board);
list_sort(sort->list);
LIST_CLEAR(sort->bad);
sort->test = TEST_CAPTURE;
} else if (gen == GEN_KILLER) {
LIST_CLEAR(sort->list);
if (sort->killer_1 != MoveNone) LIST_ADD(sort->list,sort->killer_1);
if (sort->killer_2 != MoveNone) LIST_ADD(sort->list,sort->killer_2);
sort->test = TEST_KILLER;
} else if (gen == GEN_QUIET) {
gen_quiet_moves(sort->list,sort->board);
note_quiet_moves(sort->list,sort->board);
list_sort(sort->list);
sort->test = TEST_QUIET;
} else if (gen == GEN_BAD) {
list_copy(sort->list,sort->bad);
sort->test = TEST_BAD;
} else {
ASSERT(gen==GEN_END);
return MoveNone;
}
sort->pos = 0;
}
}
bool TEngine::SearchPos(board_t * Board, TFindPos * fp, mv_t pv[], bool full)
{
//------------------------
if (Eval(Board,fp)) {
pv[0] = 0;
return true;
}
//-----------------------
if (LastMove) {
undo_t undo;
move_do(Board,LastMove,&undo);
bool eval = Eval(Board,fp);
if (Eval(Board,fp)) {
move_undo(Board,LastMove, &undo);
pv[0] = LastMove;
pv[1] = 0;
return true;
}
list_t list;
gen_legal_moves(&list,Board);
for (int i=0; i<LIST_SIZE(&list); i++) {
undo_t undo2;
mv_t move2 = LIST_MOVE(&list,i);
move_do(Board,move2,&undo2);
bool eval = Eval(Board,fp);
move_undo(Board,move2, &undo2);
if (eval) {
move_undo(Board,LastMove, &undo);
pv[0] = LastMove;
pv[1] = move2;
pv[2] = 0;
return true;;
}
}
move_undo(Board,LastMove,&undo);
}
//----------------------------------------------------
list_t list;
gen_legal_moves(&list,Board);
//----------------------------------------------------
for (int i=0; i<LIST_SIZE(&list); i++) {
undo_t undo;
mv_t move = LIST_MOVE(&list,i);
move_do(Board,move,&undo);
bool eval = Eval(Board,fp);
move_undo(Board,move,&undo);
if (eval) {
pv[0] = move;
pv[1] = 0;
return true;
}
}
//------------------------------------------------------
if (full) {
for (int i=0; i<LIST_SIZE(&list); i++) {
undo_t undo;
mv_t move = LIST_MOVE(&list,i);
move_do(Board,move,&undo);
list_t list2;
gen_legal_moves(&list2,Board);
for (int j=0; j<LIST_SIZE(&list2); j++) {
undo_t undo2;
mv_t move2 = LIST_MOVE(&list2,j);
move_do(Board,move2,&undo2);
/*
char s_move[6], s_move2[6];
move_to_string(move,s_move,6);
move_to_string(move2,s_move2,6);
*/
bool eval = Eval(Board,fp);
move_undo(Board,move2,&undo2);
if (eval) {
pv[0] = move;
pv[1] = move2;
pv[2] = 0;
move_undo(Board,move,&undo);
return true;
}
}
move_undo(Board,move,&undo);
}
}
//-------------------------------------------------------
return false;
}
static int full_search(board_t * board, int alpha, int beta, int depth, int height, mv_t pv[], int node_type) {
bool in_check;
bool single_reply;
bool mate_threat;
int trans_move, trans_depth, trans_min_depth, trans_max_depth, trans_min_value, trans_max_value;
int min_value, max_value;
int old_alpha;
int value, best_value;
int move, best_move;
int new_depth;
int played_nb;
int i;
int opt_value;
bool reduced;
int mb;
attack_t attack[1];
sort_t sort[1];
undo_t undo[1];
mv_t new_pv[HeightMax];
mv_t played[256];
int FutilityMargin;
ASSERT(board!=NULL);
ASSERT(range_is_ok(alpha,beta));
ASSERT(depth_is_ok(depth));
ASSERT(height_is_ok(height));
ASSERT(pv!=NULL);
ASSERT(node_type==NodePV||node_type==NodeCut||node_type==NodeAll);
ASSERT(board_is_legal(board));
// horizon?
if (depth <= 0){
if (node_type == NodePV)
CheckDepth = 1 - CheckNb - 1;
else
CheckDepth = 1 - CheckNb;
return full_quiescence(board,alpha,beta,0,height,pv);
}
// init
SearchStack[height].best_move = MoveNone;
SearchStack[height].move = MoveNone;
SearchStack[height].threat_move = MoveNone;
SearchStack[height].reduced = false;
mate_threat = false;
SearchCurrent->node_nb++;
SearchInfo->check_nb--;
PV_CLEAR(pv);
if (height > SearchCurrent->max_depth) SearchCurrent->max_depth = height;
if (SearchInfo->check_nb <= 0) {
SearchInfo->check_nb += SearchInfo->check_inc;
search_check();
}
// draw?
if (board_is_repetition(board) || recog_draw(board)) return ValueDraw;
// mate-distance pruning
if (UseDistancePruning) {
// lower bound
value = VALUE_MATE(height+2); // does not work if the current position is mate
if (value > alpha && board_is_mate(board)) value = VALUE_MATE(height);
if (value > alpha) {
alpha = value;
if (value >= beta) return value;
}
// upper bound
value = -VALUE_MATE(height+1);
if (value < beta) {
beta = value;
if (value <= alpha) return value;
}
}
// transposition table
trans_move = MoveNone;
if (UseTrans && depth >= TransDepth) {
if (trans_retrieve(Trans,board->key,&trans_move,&trans_min_depth,&trans_max_depth,&trans_min_value,&trans_max_value)) {
// trans_move is now updated
if (node_type != NodePV) {
if (UseMateValues) {
if (trans_min_value > +ValueEvalInf && trans_min_depth < depth) {
trans_min_depth = depth;
}
if (trans_max_value < -ValueEvalInf && trans_max_depth < depth) {
trans_max_depth = depth;
}
}
min_value = -ValueInf;
if (DEPTH_MATCH(trans_min_depth,depth)) {
min_value = value_from_trans(trans_min_value,height);
if (min_value >= beta) return min_value;
}
max_value = +ValueInf;
if (DEPTH_MATCH(trans_max_depth,depth)) {
max_value = value_from_trans(trans_max_value,height);
if (max_value <= alpha) return max_value;
}
if (min_value == max_value) return min_value; // exact match
}
}
}
// height limit
if (height >= HeightMax-1) return eval(board, alpha, beta);
// more init
old_alpha = alpha;
best_value = ValueNone;
best_move = MoveNone;
played_nb = 0;
attack_set(attack,board);
in_check = ATTACK_IN_CHECK(attack);
// null-move pruning
if (UseNull && depth >= NullDepth && node_type != NodePV) {
if (!in_check
&& !value_is_mate(beta)
&& do_null(board)
&& (!UseNullEval || depth <= NullReduction+1 || eval(board,alpha, beta) >= beta)) {
// null-move search
new_depth = depth - NullReduction - 1;
//new_depth = depth - R_adpt(board->piece_size[board->turn]+board->pawn_size[board->turn],depth,NullReduction) - 1;
move_do_null(board,undo);
value = -full_search(board,-beta,-beta+1,new_depth,height+1,new_pv,NODE_OPP(node_type));
move_undo_null(board,undo);
// verification search
if (UseVer && depth > VerReduction) {
if (value >= beta && (!UseVerEndgame || do_ver(board))) {
new_depth = depth - VerReduction;
ASSERT(new_depth>0);
value = full_no_null(board,alpha,beta,new_depth,height,new_pv,NodeCut,trans_move,&move);
if (value >= beta) {
ASSERT(move==new_pv[0]);
played[played_nb++] = move;
best_move = move;
SearchStack[height].move = move;
SearchStack[height].best_move = move;
best_value = value;
pv_copy(pv,new_pv);
goto cut;
}
}
}
// pruning
if (value >= beta) {
if (value > +ValueEvalInf) value = +ValueEvalInf; // do not return unproven mates
ASSERT(!value_is_mate(value));
// pv_cat(pv,new_pv,MoveNull);
best_move = MoveNone;
best_value = value;
goto cut;
}
SearchStack[height].threat_move = SearchStack[height+1].best_move;
/* if (SearchStack[height-1].reduced){ // Idea by Tord Romstad
if (MOVE_FROM(SearchStack[height+1].best_move) == MOVE_TO(SearchStack[height-1].move))
return alpha-1; */
/* if(((MOVE_TO(SearchStack[height - 2].threat_move) == MOVE_FROM(SearchStack[height - 2].move))
&& (MOVE_TO(SearchStack[height].threat_move) == MOVE_TO(SearchStack[height - 2].move)))
||
((MOVE_TO(SearchStack[height - 2].threat_move) != MOVE_FROM(SearchStack[height - 2].move))
&& (MOVE_TO(SearchStack[height].threat_move) == MOVE_TO(SearchStack[height - 2].threat_move))))
return alpha-1; */
// }
}
}
// mate threat
/* mate_threat = false;
if (value <= VALUE_MATE(height+2)){
mate_threat = true;
} */
// Internal Iterative Deepening
if (UseIID && depth >= IIDDepth && node_type == NodePV && trans_move == MoveNone) {
// new_depth = depth - IIDReduction;
new_depth = MIN(depth - IIDReduction,depth/2);
ASSERT(new_depth>0);
value = full_search(board,alpha,beta,new_depth,height,new_pv,node_type);
if (value <= alpha) value = full_search(board,-ValueInf,beta,new_depth,height,new_pv,node_type);
trans_move = new_pv[0];
}
// move generation
sort_init(sort,board,attack,depth,height,trans_move);
single_reply = false;
if (in_check && LIST_SIZE(sort->list) == 1) single_reply = true; // HACK
// move loop
opt_value = +ValueInf;
while ((move=sort_next(sort)) != MoveNone) {
SearchStack[height].move = move;
// history_tried(move,board);
// extensions
new_depth = full_new_depth(depth,move,board,single_reply,mate_threat,node_type==NodePV, height);
// futility pruning
if (UseFutility && depth <= 2 && node_type != NodePV) {
if (!in_check && new_depth < depth && !move_is_tactical(move,board) && !move_is_dangerous(move,board)) {
ASSERT(!move_is_check(move,board));
// optimistic evaluation
if (opt_value == +ValueInf) {
if (depth==2){
FutilityMargin = FutilityMargin2;
}
else{
FutilityMargin = FutilityMargin1;
}
opt_value = eval(board,alpha,beta) + FutilityMargin;
ASSERT(opt_value<+ValueInf);
}
value = opt_value;
// pruning
if (value <= alpha) {
if (value > best_value) {
best_value = value;
PV_CLEAR(pv);
}
continue;
}
}
}
// history pruning
/* reduced = false;
if (UseHistory && depth >= HistoryDepth && node_type != NodePV) {
if (!in_check && played_nb >= HistoryMoveNb && new_depth < depth) {
ASSERT(best_value!=ValueNone);
ASSERT(played_nb>0);
ASSERT(sort->pos>0&&move==LIST_MOVE(sort->list,sort->pos-1));
if (history_reduction(move,board) == true) {
ASSERT(value>=0&&value<16384);
ASSERT(move!=trans_move);
ASSERT(!move_is_tactical(move,board));
ASSERT(!move_is_check(move,board));
new_depth--;
reduced = true;
}
}
} */
// history pruning
reduced = false;
value = sort->value; // history score
if (!in_check && depth < SearchCurrent->max_extensions / 2 && node_type != NodePV && new_depth < depth && value < HistoryValue / depth)
continue;
if (UseHistory && depth >= HistoryDepth && node_type != NodePV) {
if (!in_check && played_nb >= HistoryMoveNb && new_depth < depth) {
ASSERT(best_value!=ValueNone);
ASSERT(played_nb>0);
ASSERT(sort->pos>0&&move==LIST_MOVE(sort->list,sort->pos-1));
value = sort->value; // history score
if (value < HistoryValue) {
ASSERT(value>=0&&value<16384);
ASSERT(move!=trans_move);
ASSERT(!move_is_tactical(move,board));
ASSERT(!move_is_check(move,board));
new_depth--;
reduced = true;
if (UseExtendedHistory && value < HistoryValue / 2 && depth >= 8){
new_depth--;
}
}
}
}
SearchStack[height].reduced = reduced;
// recursive search
move_do(board,move,undo);
if (node_type != NodePV || best_value == ValueNone) { // first move
value = -full_search(board,-beta,-alpha,new_depth,height+1,new_pv,NODE_OPP(node_type));
} else { // other moves
value = -full_search(board,-alpha-1,-alpha,new_depth,height+1,new_pv,NodeCut);
if (value > alpha) { // && value < beta
value = -full_search(board,-beta,-alpha,new_depth,height+1,new_pv,NodePV);
}
}
// history-pruning re-search
if (HistoryReSearch && reduced && value > alpha /* was >= beta */) {
ASSERT(node_type!=NodePV);
//history_very_bad(move,board);
SearchStack[height].reduced = false;
new_depth++;
ASSERT(new_depth==depth-1);
value = -full_search(board,-beta,-alpha,new_depth,height+1,new_pv,NODE_OPP(node_type));
}
move_undo(board,move,undo);
played[played_nb++] = move;
if (value > best_value) {
best_value = value;
pv_cat(pv,new_pv,move);
if (value > alpha) {
alpha = value;
best_move = move;
SearchStack[height].best_move = move;
if (value >= beta){
// history_success(move,board);
goto cut;
}
}
}
if (node_type == NodeCut) node_type = NodeAll;
}
// ALL node
if (best_value == ValueNone) { // no legal move
if (in_check) {
ASSERT(board_is_mate(board));
return VALUE_MATE(height);
} else {
ASSERT(board_is_stalemate(board));
return ValueDraw;
}
}
cut:
ASSERT(value_is_ok(best_value));
// move ordering
if (best_move != MoveNone) {
good_move(best_move,board,depth,height);
if (best_value >= beta && !move_is_tactical(best_move,board)) {
ASSERT(played_nb>0&&played[played_nb-1]==best_move);
for (i = 0; i < played_nb-1; i++) {
move = played[i];
ASSERT(move!=best_move);
history_bad(move,board);
}
history_good(best_move,board);
}
}
// transposition table
if (UseTrans && depth >= TransDepth) {
trans_move = best_move;
trans_depth = depth;
trans_min_value = (best_value > old_alpha) ? value_to_trans(best_value,height) : -ValueInf;
trans_max_value = (best_value < beta) ? value_to_trans(best_value,height) : +ValueInf;
trans_store(Trans,board->key,trans_move,trans_depth,trans_min_value,trans_max_value);
}
return best_value;
}
static int full_root(list_t * list, board_t * board, int alpha, int beta, int depth, int height, int search_type) {
int old_alpha;
int value, best_value[MultiPVMax];
int i, move, j;
int new_depth;
undo_t undo[1];
mv_t new_pv[HeightMax];
bool found;
ASSERT(list_is_ok(list));
ASSERT(board_is_ok(board));
ASSERT(range_is_ok(alpha,beta));
ASSERT(depth_is_ok(depth));
ASSERT(height_is_ok(height));
ASSERT(search_type==SearchNormal||search_type==SearchShort);
ASSERT(list==SearchRoot->list);
ASSERT(!LIST_IS_EMPTY(list));
ASSERT(board==SearchCurrent->board);
ASSERT(board_is_legal(board));
ASSERT(depth>=1);
// init
SearchStack[height].best_move = MoveNone;
SearchStack[height].move = MoveNone;
SearchStack[height].threat_move = MoveNone;
SearchStack[height].reduced = false;
SearchCurrent->node_nb++;
SearchInfo->check_nb--;
if (SearchCurrent->multipv == 0)
for (i = 0; i < LIST_SIZE(list); i++) list->value[i] = ValueNone;
old_alpha = alpha;
best_value[SearchCurrent->multipv] = ValueNone;
// move loop
for (i = 0; i < LIST_SIZE(list); i++) {
move = LIST_MOVE(list,i);
if (SearchCurrent->multipv > 0){
found = false;
for (j = 0; j < SearchCurrent->multipv; j++){
if (SearchBest[j].pv[0] == move){
found = true;
break;
}
}
if (found == true)
continue;
}
SearchStack[height].move = move;
SearchRoot->depth = depth;
SearchRoot->move = move;
SearchRoot->move_pos = i;
SearchRoot->move_nb = LIST_SIZE(list);
search_update_root();
new_depth = full_new_depth(depth,move,board,board_is_check(board)&&LIST_SIZE(list)==1,false,true, height);
move_do(board,move,undo);
if (search_type == SearchShort || best_value[SearchCurrent->multipv] == ValueNone) { // first move
value = -full_search(board,-beta,-alpha,new_depth,height+1,new_pv,NodePV);
if (value <= alpha){ // research
old_alpha = -ValueInf;
value = -full_search(board,-beta,ValueInf,new_depth,height+1,new_pv,NodePV);
}
else if (value >= beta){ // research
value = -full_search(board,-ValueInf,-alpha,new_depth,height+1,new_pv,NodePV);
}
} else { // other moves
value = -full_search(board,-alpha-1,-alpha,new_depth,height+1,new_pv,NodeCut);
if (value > alpha) { // && value < beta
SearchRoot->change = true;
SearchRoot->easy = false;
SearchRoot->flag = false;
search_update_root();
value = -full_search(board,-beta,-alpha,new_depth,height+1,new_pv,NodePV);
}
}
move_undo(board,move,undo);
if (value <= alpha) { // upper bound
list->value[i] = old_alpha;
} else if (value >= beta) { // lower bound
list->value[i] = beta;
} else { // alpha < value < beta => exact value
list->value[i] = value;
}
if (value > best_value[SearchCurrent->multipv] && (best_value[SearchCurrent->multipv] == ValueNone || value > alpha)) {
SearchBest[SearchCurrent->multipv].move = move;
SearchStack[height].best_move = move;
SearchBest[SearchCurrent->multipv].value = value;
if (value <= alpha) { // upper bound
SearchBest[SearchCurrent->multipv].flags = SearchUpper;
} else if (value >= beta) { // lower bound
SearchBest[SearchCurrent->multipv].flags = SearchLower;
} else { // alpha < value < beta => exact value
SearchBest[SearchCurrent->multipv].flags = SearchExact;
}
SearchBest[SearchCurrent->multipv].depth = depth;
pv_cat(SearchBest[SearchCurrent->multipv].pv,new_pv,move);
search_update_best();
}
if (value > best_value[SearchCurrent->multipv]) {
best_value[SearchCurrent->multipv] = value;
if (value > alpha) {
if (search_type == SearchNormal) alpha = value;
if (value >= beta) break;
}
}
}
ASSERT(value_is_ok(best_value));
list_sort(list);
ASSERT(SearchBest->move==LIST_MOVE(list,0));
ASSERT(SearchBest->value==best_value);
if (UseTrans && best_value[SearchCurrent->multipv] > old_alpha && best_value[SearchCurrent->multipv] < beta) {
pv_fill(SearchBest[SearchCurrent->multipv].pv,board);
}
return best_value[SearchCurrent->multipv];
}
