void
perform_extended_solve( int side_to_move, int actual_move,
int book, int exact_solve ) {
int i;
int mid, wld, exact;
int best_move;
int disc_diff, corrected_diff;
EvaluatedMove temp;
EvalResult res;
/* Disable all time control mechanisms */
toggle_abort_check( FALSE );
toggle_midgame_abort_check( FALSE );
toggle_perturbation_usage( FALSE );
start_move( 0, 0, disc_count( BLACKSQ ) + disc_count( WHITESQ ) );
clear_ponder_times();
determine_hash_values( side_to_move, board );
reset_counter( &nodes );
/* Set search depths that result in Zebra solving after a brief
midgame analysis */
mid = 60;
wld = 60;
if ( exact_solve )
exact = 60;
else
exact = 0;
game_evaluated_count = 1;
/* Calculate the score for the preferred move */
evaluated_list[0].side_to_move = side_to_move;
evaluated_list[0].move = actual_move;
evaluated_list[0].eval =
create_eval_info( UNDEFINED_EVAL, UNSOLVED_POSITION,
0, 0.0, 0, FALSE );
evaluated_list[0].pv_depth = 1;
evaluated_list[0].pv[0] = actual_move;
prefix_move = actual_move;
negate_current_eval( TRUE );
(void) make_move( side_to_move, actual_move, TRUE );
(void) compute_move( OPP( side_to_move ), FALSE, 0, 0, FALSE, book,
mid - 1, exact - 1, wld - 1, TRUE,
&evaluated_list[0].eval );
if ( evaluated_list[0].eval.type == PASS_EVAL ) { /* Don't allow pass */
(void) compute_move( side_to_move, FALSE, 0, 0, FALSE, book,
mid - 1, exact - 1, wld - 1, TRUE,
&evaluated_list[0].eval );
if ( evaluated_list[0].eval.type == PASS_EVAL ) { /* Game has ended */
disc_diff =
disc_count( side_to_move ) - disc_count( OPP( side_to_move ) );
if ( disc_diff > 0 ) {
corrected_diff = 64 - 2 * disc_count( OPP( side_to_move) );
res = WON_POSITION;
}
else if ( disc_diff == 0 ) {
corrected_diff = 0;
res = DRAWN_POSITION;
}
else {
corrected_diff = 2 * disc_count( side_to_move ) - 64;
res = LOST_POSITION;
}
evaluated_list[0].eval =
create_eval_info( EXACT_EVAL, res, 128 * corrected_diff,
0.0, 60 - disks_played, FALSE );
}
}
else { /* Sign-correct the score produced */
evaluated_list[0].eval.score = -evaluated_list[0].eval.score;
if ( evaluated_list[0].eval.res == WON_POSITION )
evaluated_list[0].eval.res = LOST_POSITION;
else if ( evaluated_list[0].eval.res == LOST_POSITION )
evaluated_list[0].eval.res = WON_POSITION;
}
if ( force_return )
evaluated_list[0].eval =
create_eval_info( UNDEFINED_EVAL, UNSOLVED_POSITION, 0, 0.0, 0, FALSE );
else {
evaluated_list[0].pv_depth = pv_depth[0] + 1;
evaluated_list[0].pv[0] = actual_move;
for ( i = 0; i < pv_depth[0]; i++ )
evaluated_list[0].pv[i + 1] = pv[0][i];
}
unmake_move( side_to_move, actual_move );
prefix_move = 0;
negate_current_eval( FALSE );
max_depth_reached++;
/* Compute the score for the best move and store it in the move list
if it isn't ACTUAL_MOVE */
best_move = compute_move( side_to_move, FALSE, 0, 0, FALSE, book, mid,
exact, wld, TRUE, &evaluated_list[1].eval );
if ( !force_return && (best_move != actual_move) ) {
/* Move list will contain best move first and then the actual move */
game_evaluated_count = 2;
evaluated_list[1].side_to_move = side_to_move;
evaluated_list[1].move = best_move;
evaluated_list[1].pv_depth = pv_depth[0];
for ( i = 0; i < pv_depth[0]; i++ )
evaluated_list[1].pv[i] = pv[0][i];
temp = evaluated_list[0];
evaluated_list[0] = evaluated_list[1];
evaluated_list[1] = temp;
}
/* The PV and current eval should when correspond to the best move
when leaving */
pv_depth[0] = evaluated_list[0].pv_depth;
for ( i = 0; i < pv_depth[0]; i++ )
pv[0][i] = evaluated_list[0].pv[i];
set_current_eval( evaluated_list[0].eval );
/* Don't forget to enable the time control mechanisms when leaving */
toggle_abort_check( TRUE );
toggle_midgame_abort_check( TRUE );
toggle_perturbation_usage( FALSE );
}
int
compute_move( int side_to_move,
int update_all,
int my_time,
int my_incr,
int timed_depth,
int book,
int mid,
int exact,
int wld,
int search_forced,
EvaluationType *eval_info ) {
FILE *log_file;
EvaluationType book_eval_info, mid_eval_info, end_eval_info;
char *eval_str;
double midgame_diff;
enum { INTERRUPTED_MOVE, BOOK_MOVE, MIDGAME_MOVE, ENDGAME_MOVE } move_type;
int i;
int curr_move, midgame_move;
int empties;
int midgame_depth, interrupted_depth, max_depth;
int book_move_found;
int endgame_reached;
int offset;
log_file = NULL;
if ( use_log_file )
log_file = fopen( log_file_path, "a" );
if ( log_file )
display_board( log_file, board, side_to_move, FALSE, FALSE, FALSE );
/* Initialize various components of the move system */
piece_count[BLACKSQ][disks_played] = disc_count( BLACKSQ );
piece_count[WHITESQ][disks_played] = disc_count( WHITESQ );
init_moves();
generate_all( side_to_move );
determine_hash_values( side_to_move, board );
calculate_perturbation();
if ( log_file ) {
fprintf( log_file, "%d %s: ", move_count[disks_played], MOVE_GEN_TEXT );
for ( i = 0; i < move_count[disks_played]; i++ )
fprintf( log_file, "%c%c ", TO_SQUARE( move_list[disks_played][i] ) );
fputs( "\n", log_file );
}
if ( update_all ) {
reset_counter( &evaluations );
reset_counter( &nodes );
}
for ( i = 0; i < 100; i++ )
evals[disks_played][i] = 0;
max_depth_reached = 1;
empties = 60 - disks_played;
reset_buffer_display();
determine_move_time( my_time, my_incr, disks_played + 4 );
if ( !get_ponder_move() )
clear_ponder_times();
remove_coeffs( disks_played );
/* No feasible moves? */
if ( move_count[disks_played] == 0 ) {
*eval_info = create_eval_info( PASS_EVAL, UNSOLVED_POSITION,
0.0, 0.0, 0, FALSE );
set_current_eval( *eval_info );
if ( echo ) {
eval_str = produce_eval_text( *eval_info, FALSE );
send_status( "--> " );
send_status( "%-8s ", eval_str );
display_status( stdout, FALSE );
free( eval_str );
}
if ( log_file ) {
fprintf( log_file, "%s: %s\n", BEST_MOVE_TEXT, PASS_TEXT );
fclose( log_file );
}
last_time_used = 0.0;
clear_pv();
return PASS;
}
/* If there is only one move available:
Don't waste any time, unless told so or very close to the end,
searching the position. */
if ( (empties > DISABLE_FORCED_MOVES) &&
(move_count[disks_played] == 1) &&
!search_forced ) { /* Forced move */
*eval_info = create_eval_info( FORCED_EVAL, UNSOLVED_POSITION,
0.0, 0.0, 0, FALSE );
set_current_eval( *eval_info );
if ( echo ) {
eval_str = produce_eval_text( *eval_info, FALSE );
send_status( "--> " );
send_status( "%-8s ", eval_str );
free( eval_str );
send_status( "%c%c ", TO_SQUARE( move_list[disks_played][0] ) );
display_status( stdout, FALSE );
}
if ( log_file ) {
fprintf( log_file, "%s: %c%c (%s)\n", BEST_MOVE_TEXT,
TO_SQUARE(move_list[disks_played][0]), FORCED_TEXT );
fclose( log_file );
}
last_time_used = 0.0;
return move_list[disks_played][0];
}
/* Mark the search as interrupted until a successful search
has been performed. */
move_type = INTERRUPTED_MOVE;
interrupted_depth = 0;
curr_move = move_list[disks_played][0];
/* Check the opening book for midgame moves */
book_move_found = FALSE;
midgame_move = PASS;
if ( forced_opening != NULL ) {
/* Check if the position fits the currently forced opening */
curr_move = check_forced_opening( side_to_move, forced_opening );
if ( curr_move != PASS ) {
book_eval_info = create_eval_info( UNDEFINED_EVAL, UNSOLVED_POSITION,
0, 0.0, 0, TRUE );
midgame_move = curr_move;
book_move_found = TRUE;
move_type = BOOK_MOVE;
if ( echo ) {
send_status( "--> Forced opening move " );
if ( get_ponder_move() )
send_status( "{%c%c} ", TO_SQUARE( get_ponder_move() ) );
send_status( "%c%c", TO_SQUARE( curr_move ) );
display_status( stdout, FALSE );
}
clear_pv();
pv_depth[0] = 1;
pv[0][0] = curr_move;
}
}
if ( !book_move_found && play_thor_match_openings ) {
/* Optionally use the Thor database as opening book. */
int threshold = 2;
database_search( board, side_to_move );
if ( get_match_count() >= threshold ) {
int game_index = (my_random() >> 8) % get_match_count();
curr_move = get_thor_game_move( game_index, disks_played );
if ( valid_move( curr_move, side_to_move ) ) {
book_eval_info = create_eval_info( UNDEFINED_EVAL, UNSOLVED_POSITION,
0, 0.0, 0, TRUE );
midgame_move = curr_move;
book_move_found = TRUE;
move_type = BOOK_MOVE;
if ( echo ) {
send_status( "--> %s ", THOR_TEXT );
if ( get_ponder_move() )
send_status( "{%c%c} ", TO_SQUARE( get_ponder_move() ) );
send_status( "%c%c", TO_SQUARE( curr_move ) );
display_status( stdout, FALSE );
}
clear_pv();
pv_depth[0] = 1;
pv[0][0] = curr_move;
}
else
fatal_error( "Thor book move %d is invalid!", curr_move );
}
int
extended_compute_move( int side_to_move, int book_only,
int book, int mid, int exact, int wld ) {
int i, j;
int index;
int changed;
int this_move;
int disc_diff, corrected_diff;
int best_move, temp_move;
int best_score;
int best_pv_depth;
int stored_echo;
int shallow_eval;
int empties;
int current_mid, current_exact, current_wld;
int first_iteration;
int unsearched;
int unsearched_count;
int unsearched_move[61];
int best_pv[60];
unsigned int transform1[60], transform2[60];
CandidateMove book_move;
EvaluatedMove temp;
EvaluationType book_eval_info;
EvalResult res;
/* Disable all time control mechanisms and randomization */
toggle_abort_check( FALSE );
toggle_midgame_abort_check( FALSE );
toggle_perturbation_usage( FALSE );
start_move( 0, 0, disc_count( BLACKSQ ) + disc_count( WHITESQ ) );
clear_ponder_times();
determine_hash_values( side_to_move, board );
empties = 60 - disks_played;
best_move = 0;
game_evaluated_count = 0;
reset_counter( &nodes );
generate_all( side_to_move );
if ( book_only || book ) { /* Evaluations for database moves */
int flags = 0;
if ( empties <= exact )
flags = FULL_SOLVED;
else if ( empties <= wld )
flags = WLD_SOLVED;
fill_move_alternatives( side_to_move, flags );
game_evaluated_count = get_candidate_count();
for ( i = 0; i < game_evaluated_count; i++ ) {
int child_flags;
book_move = get_candidate( i );
evaluated_list[i].side_to_move = side_to_move;
evaluated_list[i].move = book_move.move;
evaluated_list[i].pv_depth = 1;
evaluated_list[i].pv[0] = book_move.move;
evaluated_list[i].eval =
create_eval_info( UNDEFINED_EVAL, UNSOLVED_POSITION,
book_move.score, 0.0, 0, TRUE );
child_flags = book_move.flags & book_move.parent_flags;
if ( child_flags & (FULL_SOLVED | WLD_SOLVED) ) {
if ( child_flags & FULL_SOLVED )
evaluated_list[i].eval.type = EXACT_EVAL;
else
evaluated_list[i].eval.type = WLD_EVAL;
if ( book_move.score > 0 ) {
evaluated_list[i].eval.res = WON_POSITION;
/* Normalize the scores so that e.g. 33-31 becomes +256 */
evaluated_list[i].eval.score -= CONFIRMED_WIN;
evaluated_list[i].eval.score *= 128;
}
else if ( book_move.score == 0 )
evaluated_list[i].eval.res = DRAWN_POSITION;
else { /* score < 0 */
evaluated_list[i].eval.res = LOST_POSITION;
/* Normalize the scores so that e.g. 30-34 becomes -512 */
evaluated_list[i].eval.score += CONFIRMED_WIN;
evaluated_list[i].eval.score *= 128;
}
}
else
evaluated_list[i].eval.type = MIDGAME_EVAL;
}
}
if ( book_only ) { /* Only book moves are to be considered */
if ( game_evaluated_count > 0 ) {
best_move = get_book_move( side_to_move, FALSE, &book_eval_info );
set_current_eval( book_eval_info );
}
else {
pv_depth[0] = 0;
best_move = PASS;
book_eval_info = create_eval_info( UNDEFINED_EVAL, UNSOLVED_POSITION,
0, 0.0, 0, FALSE );
set_current_eval( book_eval_info );
}
}
else { /* Make searches for moves not in the database */
int shallow_depth;
int empties = 60 - disks_played;
book = FALSE;
best_score = -INFINITE_EVAL;
if ( game_evaluated_count > 0 ) { /* Book PV available */
best_score = evaluated_list[0].eval.score;
best_move = evaluated_list[0].move;
}
negate_current_eval( TRUE );
/* Store the available moves, clear their evaluations and sort
them on shallow evaluation. */
if ( empties < 12 )
shallow_depth = 1;
else {
int max_depth = MAX( mid, MAX( exact, wld ) );
if ( max_depth >= 16 )
shallow_depth = 6;
else
shallow_depth = 4;
}
unsearched_count = 0;
for ( i = 0; i < move_count[disks_played]; i++ ) {
this_move = move_list[disks_played][i];
unsearched = TRUE;
for ( j = 0; j < game_evaluated_count; j++ )
if ( evaluated_list[j].move == this_move )
unsearched = FALSE;
if ( !unsearched )
continue;
unsearched_move[unsearched_count] = this_move;
unsearched_count++;
(void) make_move( side_to_move, this_move, TRUE );
if ( shallow_depth == 1 ) /* Compute move doesn't allow depth 0 */
shallow_eval = -static_evaluation( OPP( side_to_move ) );
else {
EvaluationType shallow_info;
(void) compute_move( OPP( side_to_move ), FALSE, 0, 0, FALSE, book,
shallow_depth - 1, 0, 0, TRUE, &shallow_info );
if ( shallow_info.type == PASS_EVAL ) {
/* Don't allow pass */
(void) compute_move( side_to_move, FALSE, 0, 0, FALSE, book,
shallow_depth - 1, 0, 0, TRUE, &shallow_info );
if ( shallow_info.type == PASS_EVAL ) { /* Game over */
disc_diff =
disc_count( side_to_move ) - disc_count( OPP( side_to_move ) );
if ( disc_diff > 0 )
corrected_diff = 64 - 2 * disc_count( OPP( side_to_move) );
else if ( disc_diff == 0 )
corrected_diff = 0;
else
corrected_diff = 2 * disc_count( side_to_move ) - 64;
shallow_eval = 128 * corrected_diff;
}
else
shallow_eval = shallow_info.score;
}
else /* Sign-correct the score produced */
shallow_eval = -shallow_info.score;
}
unmake_move( side_to_move, this_move );
evals[disks_played][this_move] = shallow_eval;
}
do {
changed = FALSE;
for ( i = 0; i < unsearched_count - 1; i++ )
if ( evals[disks_played][unsearched_move[i]] <
evals[disks_played][unsearched_move[i + 1]] ) {
temp_move = unsearched_move[i];
unsearched_move[i] = unsearched_move[i + 1];
unsearched_move[i + 1] = temp_move;
changed = TRUE;
}
} while ( changed );
/* Initialize the entire list as being empty */
for ( i = 0, index = game_evaluated_count; i < unsearched_count;
i++, index++ ) {
evaluated_list[index].side_to_move = side_to_move;
evaluated_list[index].move = unsearched_move[i];
evaluated_list[index].eval =
create_eval_info( UNDEFINED_EVAL, UNSOLVED_POSITION,
0, 0.0, 0, FALSE );
evaluated_list[index].pv_depth = 1;
evaluated_list[index].pv[0] = unsearched_move[i];
if ( empties > MAX( wld, exact ) ) {
transform1[i] = abs( my_random() );
transform2[i] = abs( my_random() );
}
else {
transform1[i] = 0;
transform2[i] = 0;
}
}
stored_echo = echo;
echo = FALSE;
best_pv_depth = 0;
if ( mid == 1 ) { /* compute_move won't be called */
pv_depth[0] = 0;
piece_count[BLACKSQ][disks_played] = disc_count( BLACKSQ );
piece_count[WHITESQ][disks_played] = disc_count( WHITESQ );
}
/* Perform iterative deepening if the search depth is large enough */
#define ID_STEP 2
if ( exact > empties )
exact = empties;
if ( (exact < 12) || (empties > exact) )
current_exact = exact;
else
current_exact = (8 + (exact % 2)) - ID_STEP;
if ( wld > empties )
wld = empties;
if ( (wld < 14) || (empties > wld) )
current_wld = wld;
else
current_wld = (10 + (wld % 2)) - ID_STEP;
if ( ((empties == exact) || (empties == wld)) &&
(empties > 16) && (mid < empties - 12) )
mid = empties - 12;
if ( mid < 10 )
current_mid = mid;
else
current_mid = (6 + (mid % 2)) - ID_STEP;
first_iteration = TRUE;
do {
if ( current_mid < mid ) {
current_mid += ID_STEP;
/* Avoid performing deep midgame searches if the endgame
is reached anyway. */
if ( (empties <= wld) && (current_mid + 7 >= empties) ) {
current_wld = wld;
current_mid = mid;
}
if ( (empties <= exact) && (current_mid + 7 >= empties) ) {
current_exact = exact;
current_mid = mid;
}
}
else if ( current_wld < wld )
current_wld = wld;
else
current_exact = exact;
for ( i = 0; (i < unsearched_count) && !force_return; i++ ) {
EvaluationType this_eval;
this_move = unsearched_move[i];
/* Locate the current move in the list. This has to be done
because the moves might have been reordered during the
iterative deepening. */
index = 0;
while ( evaluated_list[index].move != this_move )
index++;
/* To avoid strange effects when browsing back and forth through
a game during the midgame, rehash the hash transformation masks
for each move unless the endgame is reached */
set_hash_transformation( transform1[i], transform2[i] );
/* Determine the score for the ith move */
prefix_move = this_move;
(void) make_move( side_to_move, this_move, TRUE );
if ( current_mid == 1 ) {
/* compute_move doesn't like 0-ply searches */
shallow_eval = static_evaluation( OPP( side_to_move ) );
this_eval =
create_eval_info( MIDGAME_EVAL, UNSOLVED_POSITION,
shallow_eval, 0.0, 0, FALSE );
}
else
(void) compute_move( OPP( side_to_move ), FALSE, 0, 0, FALSE, book,
current_mid - 1, current_exact - 1,
current_wld - 1, TRUE,
&this_eval );
if ( force_return ) { /* Clear eval and exit search immediately */
this_eval =
create_eval_info( UNDEFINED_EVAL, UNSOLVED_POSITION,
0, 0.0, 0, FALSE );
unmake_move( side_to_move, this_move );
break;
}
if ( this_eval.type == PASS_EVAL ) {
/* Don't allow pass */
if ( current_mid == 1 ) {
/* compute_move doesn't like 0-ply searches */
shallow_eval = static_evaluation( side_to_move );
this_eval =
create_eval_info( MIDGAME_EVAL, UNSOLVED_POSITION,
shallow_eval, 0.0, 0, FALSE );
}
else
(void) compute_move( side_to_move, FALSE, 0, 0, FALSE, book,
current_mid - 1, current_exact - 1,
current_wld - 1, TRUE,
&this_eval );
if ( this_eval.type == PASS_EVAL ) { /* Game over */
disc_diff =
disc_count( side_to_move ) - disc_count( OPP( side_to_move ) );
if ( disc_diff > 0 ) {
corrected_diff = 64 - 2 * disc_count( OPP( side_to_move) );
res = WON_POSITION;
}
else if ( disc_diff == 0 ) {
corrected_diff = 0;
res = DRAWN_POSITION;
}
else {
corrected_diff = 2 * disc_count( side_to_move ) - 64;
res = LOST_POSITION;
}
this_eval =
create_eval_info( EXACT_EVAL, res, 128 * corrected_diff,
0.0, 60 - disks_played, FALSE );
}
}
else { /* Sign-correct the score produced */
this_eval.score =
-this_eval.score;
if ( this_eval.res == WON_POSITION )
this_eval.res = LOST_POSITION;
else if ( this_eval.res == LOST_POSITION )
this_eval.res = WON_POSITION;
}
if ( force_return )
break;
else
evaluated_list[index].eval = this_eval;
/* Store the PV corresponding to the move */
evaluated_list[index].pv_depth = pv_depth[0] + 1;
evaluated_list[index].pv[0] = this_move;
for ( j = 0; j < pv_depth[0]; j++ )
evaluated_list[index].pv[j + 1] = pv[0][j];
/* Store the PV corresponding to the best move */
if ( evaluated_list[index].eval.score > best_score ) {
best_score = evaluated_list[index].eval.score;
best_move = this_move;
best_pv_depth = pv_depth[0];
for ( j = 0; j < best_pv_depth; j++ )
best_pv[j] = pv[0][j];
}
unmake_move( side_to_move, this_move );
/* Sort the moves evaluated */
if ( first_iteration )
game_evaluated_count++;
if ( !force_return )
do {
changed = FALSE;
for ( j = 0; j < game_evaluated_count - 1; j++ )
if ( compare_eval( evaluated_list[j].eval,
evaluated_list[j + 1].eval ) < 0 ) {
changed = TRUE;
temp = evaluated_list[j];
evaluated_list[j] = evaluated_list[j + 1];
evaluated_list[j + 1] = temp;
}
} while ( changed );
display_status(stdout, FALSE);
}
first_iteration = FALSE;
/* Reorder the moves after each iteration. Each move is moved to
the front of the list, starting with the bad moves and ending
with the best move. This ensures that unsearched_move will be
sorted w.r.t. the order in evaluated_list. */
for ( i = game_evaluated_count - 1; i >= 0; i-- ) {
int this_move = evaluated_list[i].move;
j = 0;
while ( (j != unsearched_count) && (unsearched_move[j] != this_move) )
j++;
if ( j == unsearched_count ) /* Must be book move, skip */
continue;
/* Move the move to the front of the list. */
while ( j >= 1 ) {
unsearched_move[j] = unsearched_move[j - 1];
j--;
}
unsearched_move[0] = this_move;
}
} while ( !force_return &&
((current_mid != mid) ||
(current_exact != exact) || (current_wld != wld)) );
echo = stored_echo;
game_evaluated_count = move_count[disks_played];
/* Make sure that the PV and the score correspond to the best move */
pv_depth[0] = best_pv_depth + 1;
pv[0][0] = best_move;
for ( i = 0; i < best_pv_depth; i++ )
pv[0][i + 1] = best_pv[i];
negate_current_eval( FALSE );
if ( move_count[disks_played] > 0 )
set_current_eval( evaluated_list[0].eval );
}
/* Reset the hash transformation masks prior to leaving */
set_hash_transformation( 0, 0 );
/* Don't forget to enable the time control mechanisms when leaving */
toggle_abort_check( TRUE );
toggle_midgame_abort_check( TRUE );
toggle_perturbation_usage( TRUE );
max_depth_reached++;
prefix_move = 0;
return best_move;
}
void
setup_search( void ) {
init_move_lists();
create_eval_info( UNINITIALIZED_EVAL, UNSOLVED_POSITION, 0, 0.0, 0, FALSE );
negate_eval = FALSE;
}