Line data Source code
1 : /*
2 : * tbprobe.h
3 : * (C) 2015 basil, all rights reserved,
4 : *
5 : * Permission is hereby granted, free of charge, to any person obtaining a
6 : * copy of this software and associated documentation files (the "Software"),
7 : * to deal in the Software without restriction, including without limitation
8 : * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 : * and/or sell copies of the Software, and to permit persons to whom the
10 : * Software is furnished to do so, subject to the following conditions:
11 : *
12 : * The above copyright notice and this permission notice shall be included in
13 : * all copies or substantial portions of the Software.
14 : *
15 : * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 : * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 : * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 : * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 : * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 : * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 : * DEALINGS IN THE SOFTWARE.
22 : */
23 :
24 : #ifndef TBPROBE_H
25 : #define TBPROBE_H
26 :
27 : #include <tbconfig.h>
28 :
29 : #ifdef __cplusplus
30 : extern "C"
31 : {
32 : #endif
33 :
34 : #ifndef TB_NO_STDINT
35 : #include <stdint.h>
36 : #else
37 : typedef unsigned char uint8_t;
38 : typedef unsigned short uint16_t;
39 : typedef unsigned uint32_t;
40 : typedef long long unsigned uint64_t;
41 : typedef char int8_t;
42 : typedef short int16_t;
43 : typedef int int32_t;
44 : typedef long long int64_t;
45 : #endif
46 :
47 : #ifndef TB_NO_STDBOOL
48 : #include <stdbool.h>
49 : #else
50 : #ifndef __cplusplus
51 : typedef uint8_t bool;
52 : #define true 1
53 : #define false 0
54 : #endif
55 : #endif
56 :
57 : /*
58 : * Internal definitions. Do not call these functions directly.
59 : */
60 : extern bool tb_init_impl(const char *_path);
61 : extern unsigned tb_probe_wdl_impl(
62 : uint64_t _white,
63 : uint64_t _black,
64 : uint64_t _kings,
65 : uint64_t _queens,
66 : uint64_t _rooks,
67 : uint64_t _bishops,
68 : uint64_t _knights,
69 : uint64_t _pawns,
70 : unsigned _ep,
71 : bool _turn);
72 : extern unsigned tb_probe_root_impl(
73 : uint64_t _white,
74 : uint64_t _black,
75 : uint64_t _kings,
76 : uint64_t _queens,
77 : uint64_t _rooks,
78 : uint64_t _bishops,
79 : uint64_t _knights,
80 : uint64_t _pawns,
81 : unsigned _rule50,
82 : unsigned _ep,
83 : bool _turn,
84 : unsigned *_results);
85 :
86 : /****************************************************************************/
87 : /* MAIN API */
88 : /****************************************************************************/
89 :
90 : #define TB_MAX_MOVES (192+1)
91 : #define TB_MAX_CAPTURES 64
92 : #define TB_MAX_PLY 256
93 : #define TB_CASTLING_K 0x1 /* White king-side. */
94 : #define TB_CASTLING_Q 0x2 /* White queen-side. */
95 : #define TB_CASTLING_k 0x4 /* Black king-side. */
96 : #define TB_CASTLING_q 0x8 /* Black queen-side. */
97 :
98 : #define TB_LOSS 0 /* LOSS */
99 : #define TB_BLESSED_LOSS 1 /* LOSS but 50-move draw */
100 : #define TB_DRAW 2 /* DRAW */
101 : #define TB_CURSED_WIN 3 /* WIN but 50-move draw */
102 : #define TB_WIN 4 /* WIN */
103 :
104 : #define TB_PROMOTES_NONE 0
105 : #define TB_PROMOTES_QUEEN 1
106 : #define TB_PROMOTES_ROOK 2
107 : #define TB_PROMOTES_BISHOP 3
108 : #define TB_PROMOTES_KNIGHT 4
109 :
110 : #define TB_RESULT_WDL_MASK 0x0000000F
111 : #define TB_RESULT_TO_MASK 0x000003F0
112 : #define TB_RESULT_FROM_MASK 0x0000FC00
113 : #define TB_RESULT_PROMOTES_MASK 0x00070000
114 : #define TB_RESULT_EP_MASK 0x00080000
115 : #define TB_RESULT_DTZ_MASK 0xFFF00000
116 : #define TB_RESULT_WDL_SHIFT 0
117 : #define TB_RESULT_TO_SHIFT 4
118 : #define TB_RESULT_FROM_SHIFT 10
119 : #define TB_RESULT_PROMOTES_SHIFT 16
120 : #define TB_RESULT_EP_SHIFT 19
121 : #define TB_RESULT_DTZ_SHIFT 20
122 :
123 : #define TB_GET_WDL(_res) \
124 : (((_res) & TB_RESULT_WDL_MASK) >> TB_RESULT_WDL_SHIFT)
125 : #define TB_GET_TO(_res) \
126 : (((_res) & TB_RESULT_TO_MASK) >> TB_RESULT_TO_SHIFT)
127 : #define TB_GET_FROM(_res) \
128 : (((_res) & TB_RESULT_FROM_MASK) >> TB_RESULT_FROM_SHIFT)
129 : #define TB_GET_PROMOTES(_res) \
130 : (((_res) & TB_RESULT_PROMOTES_MASK) >> TB_RESULT_PROMOTES_SHIFT)
131 : #define TB_GET_EP(_res) \
132 : (((_res) & TB_RESULT_EP_MASK) >> TB_RESULT_EP_SHIFT)
133 : #define TB_GET_DTZ(_res) \
134 : (((_res) & TB_RESULT_DTZ_MASK) >> TB_RESULT_DTZ_SHIFT)
135 :
136 : #define TB_SET_WDL(_res, _wdl) \
137 : (((_res) & ~TB_RESULT_WDL_MASK) | \
138 : (((_wdl) << TB_RESULT_WDL_SHIFT) & TB_RESULT_WDL_MASK))
139 : #define TB_SET_TO(_res, _to) \
140 : (((_res) & ~TB_RESULT_TO_MASK) | \
141 : (((_to) << TB_RESULT_TO_SHIFT) & TB_RESULT_TO_MASK))
142 : #define TB_SET_FROM(_res, _from) \
143 : (((_res) & ~TB_RESULT_FROM_MASK) | \
144 : (((_from) << TB_RESULT_FROM_SHIFT) & TB_RESULT_FROM_MASK))
145 : #define TB_SET_PROMOTES(_res, _promotes) \
146 : (((_res) & ~TB_RESULT_PROMOTES_MASK) | \
147 : (((_promotes) << TB_RESULT_PROMOTES_SHIFT) & TB_RESULT_PROMOTES_MASK))
148 : #define TB_SET_EP(_res, _ep) \
149 : (((_res) & ~TB_RESULT_EP_MASK) | \
150 : (((_ep) << TB_RESULT_EP_SHIFT) & TB_RESULT_EP_MASK))
151 : #define TB_SET_DTZ(_res, _dtz) \
152 : (((_res) & ~TB_RESULT_DTZ_MASK) | \
153 : (((_dtz) << TB_RESULT_DTZ_SHIFT) & TB_RESULT_DTZ_MASK))
154 :
155 : #define TB_RESULT_CHECKMATE TB_SET_WDL(0, TB_WIN)
156 : #define TB_RESULT_STALEMATE TB_SET_WDL(0, TB_DRAW)
157 : #define TB_RESULT_FAILED 0xFFFFFFFF
158 :
159 : /*
160 : * The tablebase can be probed for any position where #pieces <= TB_LARGEST.
161 : */
162 : extern unsigned TB_LARGEST;
163 :
164 : /*
165 : * Initialize the tablebase.
166 : *
167 : * PARAMETERS:
168 : * - path:
169 : * The tablebase PATH string.
170 : *
171 : * RETURN:
172 : * - true=success, false=failed. The TB_LARGEST global will also be
173 : * initialized. If no tablebase files are found, then `true' is returned
174 : * and TB_LARGEST is set to zero.
175 : */
176 : bool tb_init(const char *_path);
177 :
178 : /*
179 : * Free any resources allocated by tb_init
180 : */
181 : void tb_free(void);
182 :
183 : /*
184 : * Probe the Win-Draw-Loss (WDL) table.
185 : *
186 : * PARAMETERS:
187 : * - white, black, kings, queens, rooks, bishops, knights, pawns:
188 : * The current position (bitboards).
189 : * - rule50:
190 : * The 50-move half-move clock.
191 : * - castling:
192 : * Castling rights. Set to zero if no castling is possible.
193 : * - ep:
194 : * The en passant square (if exists). Set to zero if there is no en passant
195 : * square.
196 : * - turn:
197 : * true=white, false=black
198 : *
199 : * RETURN:
200 : * - One of {TB_LOSS, TB_BLESSED_LOSS, TB_DRAW, TB_CURSED_WIN, TB_WIN}.
201 : * Otherwise returns TB_RESULT_FAILED if the probe failed.
202 : *
203 : * NOTES:
204 : * - Engines should use this function during search.
205 : * - This function is thread safe assuming TB_NO_THREADS is disabled.
206 : */
207 : static inline unsigned tb_probe_wdl(
208 : uint64_t _white,
209 : uint64_t _black,
210 : uint64_t _kings,
211 : uint64_t _queens,
212 : uint64_t _rooks,
213 : uint64_t _bishops,
214 : uint64_t _knights,
215 : uint64_t _pawns,
216 : unsigned _rule50,
217 : unsigned _castling,
218 : unsigned _ep,
219 : bool _turn)
220 : {
221 0 : if (_castling != 0)
222 : return TB_RESULT_FAILED;
223 0 : if (_rule50 != 0)
224 : return TB_RESULT_FAILED;
225 0 : return tb_probe_wdl_impl(_white, _black, _kings, _queens, _rooks,
226 : _bishops, _knights, _pawns, _ep, _turn);
227 : }
228 :
229 : /*
230 : * Probe the Distance-To-Zero (DTZ) table.
231 : *
232 : * PARAMETERS:
233 : * - white, black, kings, queens, rooks, bishops, knights, pawns:
234 : * The current position (bitboards).
235 : * - rule50:
236 : * The 50-move half-move clock.
237 : * - castling:
238 : * Castling rights. Set to zero if no castling is possible.
239 : * - ep:
240 : * The en passant square (if exists). Set to zero if there is no en passant
241 : * square.
242 : * - turn:
243 : * true=white, false=black
244 : * - results (OPTIONAL):
245 : * Alternative results, one for each possible legal move. The passed array
246 : * must be TB_MAX_MOVES in size.
247 : * If alternative results are not desired then set results=NULL.
248 : *
249 : * RETURN:
250 : * - A TB_RESULT value comprising:
251 : * 1) The WDL value (TB_GET_WDL)
252 : * 2) The suggested move (TB_GET_FROM, TB_GET_TO, TB_GET_PROMOTES, TB_GET_EP)
253 : * 3) The DTZ value (TB_GET_DTZ)
254 : * The suggested move is guaranteed to preserved the WDL value.
255 : *
256 : * Otherwise:
257 : * 1) TB_RESULT_STALEMATE is returned if the position is in stalemate.
258 : * 2) TB_RESULT_CHECKMATE is returned if the position is in checkmate.
259 : * 3) TB_RESULT_FAILED is returned if the probe failed.
260 : *
261 : * If results!=NULL, then a TB_RESULT for each legal move will be generated
262 : * and stored in the results array. The results array will be terminated
263 : * by TB_RESULT_FAILED.
264 : *
265 : * NOTES:
266 : * - Engines can use this function to probe at the root. This function should
267 : * not be used during search.
268 : * - DTZ tablebases can suggest unnatural moves, especially for losing
269 : * positions. Engines may prefer to traditional search combined with WDL
270 : * move filtering using the alternative results array.
271 : * - This function is NOT thread safe. For engines this function should only
272 : * be called once at the root per search.
273 : */
274 : static inline unsigned tb_probe_root(
275 : uint64_t _white,
276 : uint64_t _black,
277 : uint64_t _kings,
278 : uint64_t _queens,
279 : uint64_t _rooks,
280 : uint64_t _bishops,
281 : uint64_t _knights,
282 : uint64_t _pawns,
283 : unsigned _rule50,
284 : unsigned _castling,
285 : unsigned _ep,
286 : bool _turn,
287 : unsigned *_results)
288 : {
289 0 : if (_castling != 0)
290 : return TB_RESULT_FAILED;
291 0 : return tb_probe_root_impl(_white, _black, _kings, _queens, _rooks,
292 : _bishops, _knights, _pawns, _rule50, _ep, _turn, _results);
293 : }
294 :
295 : typedef uint16_t TbMove;
296 :
297 : #define TB_MOVE_FROM(move) \
298 : (((move) >> 6) & 0x3F)
299 : #define TB_MOVE_TO(move) \
300 : ((move) & 0x3F)
301 : #define TB_MOVE_PROMOTES(move) \
302 : (((move) >> 12) & 0x7)
303 :
304 : struct TbRootMove {
305 : TbMove move;
306 : TbMove pv[TB_MAX_PLY];
307 : unsigned pvSize;
308 : int32_t tbScore, tbRank;
309 : };
310 :
311 : struct TbRootMoves {
312 : unsigned size;
313 : struct TbRootMove moves[TB_MAX_MOVES];
314 : };
315 :
316 : /*
317 : * Use the DTZ tables to rank and score all root moves.
318 : * INPUT: as for tb_probe_root
319 : * OUTPUT: TbRootMoves structure is filled in. This contains
320 : * an array of TbRootMove structures.
321 : * Each structure instance contains a rank, a score, and a
322 : * predicted principal variation.
323 : * RETURN VALUE:
324 : * non-zero if ok, 0 means not all probes were successful
325 : *
326 : */
327 : int tb_probe_root_dtz(
328 : uint64_t _white,
329 : uint64_t _black,
330 : uint64_t _kings,
331 : uint64_t _queens,
332 : uint64_t _rooks,
333 : uint64_t _bishops,
334 : uint64_t _knights,
335 : uint64_t _pawns,
336 : unsigned _rule50,
337 : unsigned _castling,
338 : unsigned _ep,
339 : bool _turn,
340 : bool hasRepeated,
341 : bool useRule50,
342 : struct TbRootMoves *_results);
343 :
344 : /*
345 : // Use the WDL tables to rank and score all root moves.
346 : // This is a fallback for the case that some or all DTZ tables are missing.
347 : * INPUT: as for tb_probe_root
348 : * OUTPUT: TbRootMoves structure is filled in. This contains
349 : * an array of TbRootMove structures.
350 : * Each structure instance contains a rank, a score, and a
351 : * predicted principal variation.
352 : * RETURN VALUE:
353 : * non-zero if ok, 0 means not all probes were successful
354 : *
355 : */
356 : int tb_probe_root_wdl(uint64_t _white,
357 : uint64_t _black,
358 : uint64_t _kings,
359 : uint64_t _queens,
360 : uint64_t _rooks,
361 : uint64_t _bishops,
362 : uint64_t _knights,
363 : uint64_t _pawns,
364 : unsigned _rule50,
365 : unsigned _castling,
366 : unsigned _ep,
367 : bool _turn,
368 : bool useRule50,
369 : struct TbRootMoves *_results);
370 :
371 : /****************************************************************************/
372 : /* HELPER API */
373 : /****************************************************************************/
374 :
375 : /*
376 : * The HELPER API provides some useful additional functions. It is optional
377 : * and can be disabled by defining TB_NO_HELPER_API. Engines should disable
378 : * the HELPER API.
379 : */
380 :
381 : #ifndef TB_NO_HELPER_API
382 :
383 : extern unsigned tb_pop_count(uint64_t _bb);
384 : extern unsigned tb_lsb(uint64_t _bb);
385 : extern uint64_t tb_pop_lsb(uint64_t _bb);
386 : extern uint64_t tb_king_attacks(unsigned _square);
387 : extern uint64_t tb_queen_attacks(unsigned _square, uint64_t _occ);
388 : extern uint64_t tb_rook_attacks(unsigned _square, uint64_t _occ);
389 : extern uint64_t tb_bishop_attacks(unsigned _square, uint64_t _occ);
390 : extern uint64_t tb_knight_attacks(unsigned _square);
391 : extern uint64_t tb_pawn_attacks(unsigned _square, bool _color);
392 :
393 : #endif
394 :
395 : #ifdef __cplusplus
396 : }
397 : #endif
398 :
399 : #endif
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