From: Marco Costalba Date: Thu, 2 Jul 2009 14:49:41 +0000 (+0200) Subject: Retire USE_COMPACT_ROOK_ATTACKS and USE_FOLDED_BITSCAN defines X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=063e2441b17b8260de443b3d580f49b3d65d03c7 Retire USE_COMPACT_ROOK_ATTACKS and USE_FOLDED_BITSCAN defines This greatly simplifies bitboard.cpp that now has only two setups, respectively for 32 and 64 bits CPU according to IS_64BIT define that is automatically set but can be tweaked manually in bitboard.h No functional change both in 32 and in 64 bits. Signed-off-by: Marco Costalba --- diff --git a/Readme.txt b/Readme.txt index dc76d742..0c6f5c72 100644 --- a/Readme.txt +++ b/Readme.txt @@ -45,7 +45,6 @@ PolyGlot documentation. The book file can be selected by setting the UCI parameter "Book File". - 4. Compiling it yourself ------------------------ @@ -54,27 +53,9 @@ Stockfish directly from the source code with the included Makefile. The exception is computer with big-endian CPUs, like PowerPC Macintoshes. Some of the bitboard routines in the current version of Stockfish are endianness-sensitive, and won't work on a big-endian CPU. -Ensuring that the line with #define USE_32BIT_ATTACKS" near the top -of bitboard.h is commented out should solve this problem. -Commenting out the line with "#define USE_32BIT_ATTACKS" near the - -There is also a problem with compiling Stockfish on certain 64-bit -systems, regardless of the endianness. If Stockfish segfaults -immediately after startup, try to comment out the line with -"#define USE_FOLDED_BITSCAN" near the beginning of bitboard.h and -recompile. - -Finally, even if Stockfish does work without any changes on your -computer, it might be possible to improve the performance by changing -some of the #define directives in bitboard.h. The default settings -are optimized for 64-bit CPUs. On 32-bit CPUs, it is probably better -to switch on USE_32BIT_ATTACKS, and to use BITCOUNT_SWAR_32 instead of -BITCOUNT_SWAR_64. For computers with very little memory (like -handheld devices), it is possible to conserve memory by defining -USE_COMPACT_ROOK_ATTACKS. - - -6. Terms of use + + +5. Terms of use --------------- Stockfish is free, and distributed under the GNU General Public License @@ -93,7 +74,7 @@ For full details, read the copy of the GPL found in the file named Copying.txt. -7. Feedback +6. Feedback ----------- The author's e-mail address is mcostalba@gmail.com diff --git a/src/bitboard.cpp b/src/bitboard.cpp index a73c5a2d..ba03d66e 100644 --- a/src/bitboard.cpp +++ b/src/bitboard.cpp @@ -22,16 +22,6 @@ //// Includes //// -#ifdef _MSC_VER - #include - #ifdef _WIN64 - #pragma intrinsic(_BitScanForward64) - #else - #pragma intrinsic(_BitScanForward) - #endif - #define USING_INTRINSICS -#endif - #include #include "bitboard.h" @@ -39,46 +29,33 @@ #include "direction.h" -#if defined(USE_COMPACT_ROOK_ATTACKS) - -Bitboard RankAttacks[8][64], FileAttacks[8][64]; - -#elif defined(USE_32BIT_ATTACKS) - -const uint64_t RMult[64] = { - 0xd7445cdec88002c0ULL, 0xd0a505c1f2001722ULL, 0xe065d1c896002182ULL, - 0x9a8c41e75a000892ULL, 0x8900b10c89002aa8ULL, 0x9b28d1c1d60005a2ULL, - 0x15d6c88de002d9aULL, 0xb1dbfc802e8016a9ULL, 0x149a1042d9d60029ULL, - 0xb9c08050599e002fULL, 0x132208c3af300403ULL, 0xc1000ce2e9c50070ULL, - 0x9d9aa13c99020012ULL, 0xb6b078daf71e0046ULL, 0x9d880182fb6e002eULL, - 0x52889f467e850037ULL, 0xda6dc008d19a8480ULL, 0x468286034f902420ULL, - 0x7140ac09dc54c020ULL, 0xd76ffffa39548808ULL, 0xea901c4141500808ULL, - 0xc91004093f953a02ULL, 0x2882afa8f6bb402ULL, 0xaebe335692442c01ULL, - 0xe904a22079fb91eULL, 0x13a514851055f606ULL, 0x76c782018c8fe632ULL, - 0x1dc012a9d116da06ULL, 0x3c9e0037264fffa6ULL, 0x2036002853c6e4a2ULL, - 0xe3fe08500afb47d4ULL, 0xf38af25c86b025c2ULL, 0xc0800e2182cf9a40ULL, - 0x72002480d1f60673ULL, 0x2500200bae6e9b53ULL, 0xc60018c1eefca252ULL, - 0x600590473e3608aULL, 0x46002c4ab3fe51b2ULL, 0xa200011486bcc8d2ULL, - 0xb680078095784c63ULL, 0x2742002639bf11aeULL, 0xc7d60021a5bdb142ULL, - 0xc8c04016bb83d820ULL, 0xbd520028123b4842ULL, 0x9d1600344ac2a832ULL, - 0x6a808005631c8a05ULL, 0x604600a148d5389aULL, 0xe2e40103d40dea65ULL, - 0x945b5a0087c62a81ULL, 0x12dc200cd82d28eULL, 0x2431c600b5f9ef76ULL, - 0xfb142a006a9b314aULL, 0x6870e00a1c97d62ULL, 0x2a9db2004a2689a2ULL, - 0xd3594600caf5d1a2ULL, 0xee0e4900439344a7ULL, 0x89c4d266ca25007aULL, - 0x3e0013a2743f97e3ULL, 0x180e31a0431378aULL, 0x3a9e465a4d42a512ULL, - 0x98d0a11a0c0d9cc2ULL, 0x8e711c1aba19b01eULL, 0x8dcdc836dd201142ULL, - 0x5ac08a4735370479ULL, -}; +#if defined(IS_64BIT) -const int RShift[64] = { - 20, 21, 21, 21, 21, 21, 21, 20, 21, 22, 22, 22, 22, 22, 22, 21, - 21, 22, 22, 22, 22, 22, 22, 21, 21, 22, 22, 22, 22, 22, 22, 21, - 21, 22, 22, 22, 22, 22, 22, 21, 21, 22, 22, 22, 22, 22, 22, 21, - 21, 22, 22, 22, 22, 22, 22, 21, 20, 21, 21, 21, 21, 21, 21, 20 +const uint64_t BMult[64] = { + 0x440049104032280ULL, 0x1021023c82008040ULL, 0x404040082000048ULL, + 0x48c4440084048090ULL, 0x2801104026490000ULL, 0x4100880442040800ULL, + 0x181011002e06040ULL, 0x9101004104200e00ULL, 0x1240848848310401ULL, + 0x2000142828050024ULL, 0x1004024d5000ULL, 0x102044400800200ULL, + 0x8108108820112000ULL, 0xa880818210c00046ULL, 0x4008008801082000ULL, + 0x60882404049400ULL, 0x104402004240810ULL, 0xa002084250200ULL, + 0x100b0880801100ULL, 0x4080201220101ULL, 0x44008080a00000ULL, + 0x202200842000ULL, 0x5006004882d00808ULL, 0x200045080802ULL, + 0x86100020200601ULL, 0xa802080a20112c02ULL, 0x80411218080900ULL, + 0x200a0880080a0ULL, 0x9a01010000104000ULL, 0x28008003100080ULL, + 0x211021004480417ULL, 0x401004188220806ULL, 0x825051400c2006ULL, + 0x140c0210943000ULL, 0x242800300080ULL, 0xc2208120080200ULL, + 0x2430008200002200ULL, 0x1010100112008040ULL, 0x8141050100020842ULL, + 0x822081014405ULL, 0x800c049e40400804ULL, 0x4a0404028a000820ULL, + 0x22060201041200ULL, 0x360904200840801ULL, 0x881a08208800400ULL, + 0x60202c00400420ULL, 0x1204440086061400ULL, 0x8184042804040ULL, + 0x64040315300400ULL, 0xc01008801090a00ULL, 0x808010401140c00ULL, + 0x4004830c2020040ULL, 0x80005002020054ULL, 0x40000c14481a0490ULL, + 0x10500101042048ULL, 0x1010100200424000ULL, 0x640901901040ULL, + 0xa0201014840ULL, 0x840082aa011002ULL, 0x10010840084240aULL, + 0x420400810420608ULL, 0x8d40230408102100ULL, 0x4a00200612222409ULL, + 0xa08520292120600ULL }; -#else // if defined(USE_32BIT_ATTACKS) - const uint64_t RMult[64] = { 0xa8002c000108020ULL, 0x4440200140003000ULL, 0x8080200010011880ULL, 0x380180080141000ULL, 0x1a00060008211044ULL, 0x410001000a0c0008ULL, @@ -104,6 +81,13 @@ const uint64_t RMult[64] = { 0x410201ce5c030092ULL }; +const int BShift[64] = { + 58, 59, 59, 59, 59, 59, 59, 58, 59, 59, 59, 59, 59, 59, 59, 59, + 59, 59, 57, 57, 57, 57, 59, 59, 59, 59, 57, 55, 55, 57, 59, 59, + 59, 59, 57, 55, 55, 57, 59, 59, 59, 59, 57, 57, 57, 57, 59, 59, + 59, 59, 59, 59, 59, 59, 59, 59, 58, 59, 59, 59, 59, 59, 59, 58 +}; + const int RShift[64] = { 52, 53, 53, 53, 53, 53, 53, 52, 53, 54, 54, 54, 54, 54, 54, 53, 53, 54, 54, 54, 54, 54, 54, 53, 53, 54, 54, 54, 54, 54, 54, 53, @@ -111,15 +95,7 @@ const int RShift[64] = { 53, 54, 54, 54, 54, 54, 54, 53, 52, 53, 53, 53, 53, 53, 53, 52 }; -#endif // defined(USE_32BIT_ATTACKS) - -#if !defined(USE_COMPACT_ROOK_ATTACKS) -Bitboard RMask[64]; -int RAttackIndex[64]; -Bitboard RAttacks[0x19000]; -#endif - -#if defined(USE_32BIT_ATTACKS) +#else // if !defined(IS_64BIT) const uint64_t BMult[64] = { 0x54142844c6a22981ULL, 0x710358a6ea25c19eULL, 0x704f746d63a4a8dcULL, @@ -146,6 +122,31 @@ const uint64_t BMult[64] = { 0xdc01f6dca4bebbdcULL, }; +const uint64_t RMult[64] = { + 0xd7445cdec88002c0ULL, 0xd0a505c1f2001722ULL, 0xe065d1c896002182ULL, + 0x9a8c41e75a000892ULL, 0x8900b10c89002aa8ULL, 0x9b28d1c1d60005a2ULL, + 0x15d6c88de002d9aULL, 0xb1dbfc802e8016a9ULL, 0x149a1042d9d60029ULL, + 0xb9c08050599e002fULL, 0x132208c3af300403ULL, 0xc1000ce2e9c50070ULL, + 0x9d9aa13c99020012ULL, 0xb6b078daf71e0046ULL, 0x9d880182fb6e002eULL, + 0x52889f467e850037ULL, 0xda6dc008d19a8480ULL, 0x468286034f902420ULL, + 0x7140ac09dc54c020ULL, 0xd76ffffa39548808ULL, 0xea901c4141500808ULL, + 0xc91004093f953a02ULL, 0x2882afa8f6bb402ULL, 0xaebe335692442c01ULL, + 0xe904a22079fb91eULL, 0x13a514851055f606ULL, 0x76c782018c8fe632ULL, + 0x1dc012a9d116da06ULL, 0x3c9e0037264fffa6ULL, 0x2036002853c6e4a2ULL, + 0xe3fe08500afb47d4ULL, 0xf38af25c86b025c2ULL, 0xc0800e2182cf9a40ULL, + 0x72002480d1f60673ULL, 0x2500200bae6e9b53ULL, 0xc60018c1eefca252ULL, + 0x600590473e3608aULL, 0x46002c4ab3fe51b2ULL, 0xa200011486bcc8d2ULL, + 0xb680078095784c63ULL, 0x2742002639bf11aeULL, 0xc7d60021a5bdb142ULL, + 0xc8c04016bb83d820ULL, 0xbd520028123b4842ULL, 0x9d1600344ac2a832ULL, + 0x6a808005631c8a05ULL, 0x604600a148d5389aULL, 0xe2e40103d40dea65ULL, + 0x945b5a0087c62a81ULL, 0x12dc200cd82d28eULL, 0x2431c600b5f9ef76ULL, + 0xfb142a006a9b314aULL, 0x6870e00a1c97d62ULL, 0x2a9db2004a2689a2ULL, + 0xd3594600caf5d1a2ULL, 0xee0e4900439344a7ULL, 0x89c4d266ca25007aULL, + 0x3e0013a2743f97e3ULL, 0x180e31a0431378aULL, 0x3a9e465a4d42a512ULL, + 0x98d0a11a0c0d9cc2ULL, 0x8e711c1aba19b01eULL, 0x8dcdc836dd201142ULL, + 0x5ac08a4735370479ULL, +}; + const int BShift[64] = { 26, 27, 27, 27, 27, 27, 27, 26, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 25, 25, 25, 25, 27, 27, 27, 27, 25, 23, 23, 25, 27, 27, @@ -153,41 +154,19 @@ const int BShift[64] = { 27, 27, 27, 27, 27, 27, 27, 27, 26, 27, 27, 27, 27, 27, 27, 26 }; -#else // if defined(USE_32BIT_ATTACKS) - -const uint64_t BMult[64] = { - 0x440049104032280ULL, 0x1021023c82008040ULL, 0x404040082000048ULL, - 0x48c4440084048090ULL, 0x2801104026490000ULL, 0x4100880442040800ULL, - 0x181011002e06040ULL, 0x9101004104200e00ULL, 0x1240848848310401ULL, - 0x2000142828050024ULL, 0x1004024d5000ULL, 0x102044400800200ULL, - 0x8108108820112000ULL, 0xa880818210c00046ULL, 0x4008008801082000ULL, - 0x60882404049400ULL, 0x104402004240810ULL, 0xa002084250200ULL, - 0x100b0880801100ULL, 0x4080201220101ULL, 0x44008080a00000ULL, - 0x202200842000ULL, 0x5006004882d00808ULL, 0x200045080802ULL, - 0x86100020200601ULL, 0xa802080a20112c02ULL, 0x80411218080900ULL, - 0x200a0880080a0ULL, 0x9a01010000104000ULL, 0x28008003100080ULL, - 0x211021004480417ULL, 0x401004188220806ULL, 0x825051400c2006ULL, - 0x140c0210943000ULL, 0x242800300080ULL, 0xc2208120080200ULL, - 0x2430008200002200ULL, 0x1010100112008040ULL, 0x8141050100020842ULL, - 0x822081014405ULL, 0x800c049e40400804ULL, 0x4a0404028a000820ULL, - 0x22060201041200ULL, 0x360904200840801ULL, 0x881a08208800400ULL, - 0x60202c00400420ULL, 0x1204440086061400ULL, 0x8184042804040ULL, - 0x64040315300400ULL, 0xc01008801090a00ULL, 0x808010401140c00ULL, - 0x4004830c2020040ULL, 0x80005002020054ULL, 0x40000c14481a0490ULL, - 0x10500101042048ULL, 0x1010100200424000ULL, 0x640901901040ULL, - 0xa0201014840ULL, 0x840082aa011002ULL, 0x10010840084240aULL, - 0x420400810420608ULL, 0x8d40230408102100ULL, 0x4a00200612222409ULL, - 0xa08520292120600ULL +const int RShift[64] = { + 20, 21, 21, 21, 21, 21, 21, 20, 21, 22, 22, 22, 22, 22, 22, 21, + 21, 22, 22, 22, 22, 22, 22, 21, 21, 22, 22, 22, 22, 22, 22, 21, + 21, 22, 22, 22, 22, 22, 22, 21, 21, 22, 22, 22, 22, 22, 22, 21, + 21, 22, 22, 22, 22, 22, 22, 21, 20, 21, 21, 21, 21, 21, 21, 20 }; -const int BShift[64] = { - 58, 59, 59, 59, 59, 59, 59, 58, 59, 59, 59, 59, 59, 59, 59, 59, - 59, 59, 57, 57, 57, 57, 59, 59, 59, 59, 57, 55, 55, 57, 59, 59, - 59, 59, 57, 55, 55, 57, 59, 59, 59, 59, 57, 57, 57, 57, 59, 59, - 59, 59, 59, 59, 59, 59, 59, 59, 58, 59, 59, 59, 59, 59, 59, 58 -}; +#endif + -#endif // defined(USE_32BIT_ATTACKS) +Bitboard RMask[64]; +int RAttackIndex[64]; +Bitboard RAttacks[0x19000]; Bitboard BMask[64]; int BAttackIndex[64]; @@ -226,9 +205,6 @@ namespace { const int shift[2], const Bitboard mult[], int deltas[][2]); void init_pseudo_attacks(); -#if defined(USE_COMPACT_ROOK_ATTACKS) - void init_file_and_rank_attacks(); -#endif } @@ -260,41 +236,25 @@ void init_bitboards() { init_ray_bitboards(); init_attacks(); init_between_bitboards(); -#if defined(USE_COMPACT_ROOK_ATTACKS) - init_file_and_rank_attacks(); -#else - init_sliding_attacks(RAttacks, RAttackIndex, RMask, RShift, - RMult, rookDeltas); -#endif - init_sliding_attacks(BAttacks, BAttackIndex, BMask, BShift, - BMult, bishopDeltas); + init_sliding_attacks(RAttacks, RAttackIndex, RMask, RShift, RMult, rookDeltas); + init_sliding_attacks(BAttacks, BAttackIndex, BMask, BShift, BMult, bishopDeltas); init_pseudo_attacks(); } -#if defined(USE_FOLDED_BITSCAN) - -static const int BitTable[64] = { - 63, 30, 3, 32, 25, 41, 22, 33, 15, 50, 42, 13, 11, 53, 19, 34, 61, 29, 2, - 51, 21, 43, 45, 10, 18, 47, 1, 54, 9, 57, 0, 35, 62, 31, 40, 4, 49, 5, 52, - 26, 60, 6, 23, 44, 46, 27, 56, 16, 7, 39, 48, 24, 59, 14, 12, 55, 38, 28, - 58, 20, 37, 17, 36, 8 -}; - +/// pop_1st_bit() finds and clears the least significant nonzero bit in a +/// nonzero bitboard. -/// first_1() finds the least significant nonzero bit in a nonzero bitboard. +#if defined(IS_64BIT) -Square first_1(Bitboard b) { - b ^= (b - 1); - uint32_t fold = int(b) ^ int(b >> 32); +Square pop_1st_bit(Bitboard *b) { + Bitboard bb = *b ^ (*b - 1); + uint32_t fold = int(bb) ^ int(bb >> 32); + *b &= (*b - 1); return Square(BitTable[(fold * 0x783a9b23) >> 26]); } - -/// pop_1st_bit() finds and clears the least significant nonzero bit in a -/// nonzero bitboard. - -#if defined(USE_32BIT_ATTACKS) +#else // Use type-punning union b_union { @@ -329,46 +289,8 @@ Square pop_1st_bit(Bitboard *bb) { return Square(BitTable[(b * 0x783a9b23) >> 26]); } -#else - -Square pop_1st_bit(Bitboard *b) { - Bitboard bb = *b ^ (*b - 1); - uint32_t fold = int(bb) ^ int(bb >> 32); - *b &= (*b - 1); - return Square(BitTable[(fold * 0x783a9b23) >> 26]); -} - #endif -#else // defined(USE_FOLDED_BITSCAN) - -static const int BitTable[64] = { - 0, 1, 2, 7, 3, 13, 8, 19, 4, 25, 14, 28, 9, 34, 20, 40, 5, 17, 26, 38, 15, - 46, 29, 48, 10, 31, 35, 54, 21, 50, 41, 57, 63, 6, 12, 18, 24, 27, 33, 39, - 16, 37, 45, 47, 30, 53, 49, 56, 62, 11, 23, 32, 36, 44, 52, 55, 61, 22, 43, - 51, 60, 42, 59, 58 -}; - - -/// first_1() finds the least significant nonzero bit in a nonzero bitboard. - -Square first_1(Bitboard b) { - return Square(BitTable[((b & -b) * 0x218a392cd3d5dbfULL) >> 58]); -} - - -/// pop_1st_bit() finds and clears the least significant nonzero bit in a -/// nonzero bitboard. - -Square pop_1st_bit(Bitboard *b) { - Bitboard bb = *b; - *b &= (*b - 1); - return Square(BitTable[((bb & -bb) * 0x218a392cd3d5dbfULL) >> 58]); -} - -#endif // defined(USE_FOLDED_BITSCAN) - - namespace { // All functions below are used to precompute various bitboards during @@ -481,25 +403,25 @@ namespace { attackIndex[i] = index; mask[i] = sliding_attacks(i, 0ULL, 4, deltas, 1, 6, 1, 6); -#if defined(USE_32BIT_ATTACKS) - j = (1 << (32 - shift[i])); -#else +#if defined(IS_64BIT) j = (1 << (64 - shift[i])); +#else + j = (1 << (32 - shift[i])); #endif for(k = 0; k < j; k++) { -#if defined(USE_32BIT_ATTACKS) +#if defined(IS_64BIT) + b = index_to_bitboard(k, mask[i]); + attacks[index + ((b * mult[i]) >> shift[i])] = + sliding_attacks(i, b, 4, deltas); +#else b = index_to_bitboard(k, mask[i]); attacks[index + (unsigned(int(b) * int(mult[i]) ^ int(b >> 32) * int(mult[i] >> 32)) >> shift[i])] = sliding_attacks(i, b, 4, deltas); -#else - b = index_to_bitboard(k, mask[i]); - attacks[index + ((b * mult[i]) >> shift[i])] = - sliding_attacks(i, b, 4, deltas); #endif } index += j; @@ -516,29 +438,4 @@ namespace { } } -#if defined(USE_COMPACT_ROOK_ATTACKS) - void init_file_and_rank_attacks() { - int i, j, k, l, m, s; - Bitboard b1, b2; - for(i = 0; i < 64; i++) { - - for(m = 0; m <= 1; m++) { - b1 = 0ULL; - for(j = 0; j < 6; j++) if(i & (1<= 0 && l <= 7; l += s) { - b2 |= (m? RankBB[l] : FileBB[l]); - if(b1 & (1ULL << (l*(1+m*7)))) break; - } - } - if(m) FileAttacks[j][(b1*0xd6e8802041d0c441ULL) >> 58] = b2; - else RankAttacks[j][i] = b2; - } - } - } - } -#endif // defined(USE_COMPACT_ROOK_ATTACKS) - } diff --git a/src/bitboard.h b/src/bitboard.h index 54ed5053..3429c42e 100644 --- a/src/bitboard.h +++ b/src/bitboard.h @@ -26,10 +26,6 @@ //// Defines //// -// Comment following define if you prefer manually adjust -// platform macros defined below -#define AUTO_CONFIGURATION - // Quiet a warning on Intel compiler #if !defined(__SIZEOF_INT__ ) #define __SIZEOF_INT__ 0 @@ -40,19 +36,6 @@ #define IS_64BIT #endif -#if !defined(AUTO_CONFIGURATION) || defined(IS_64BIT) - -//#define USE_COMPACT_ROOK_ATTACKS -//#define USE_32BIT_ATTACKS -#define USE_FOLDED_BITSCAN - -#else - -#define USE_32BIT_ATTACKS -#define USE_FOLDED_BITSCAN - -#endif - //// //// Includes //// @@ -144,6 +127,13 @@ const Bitboard InFrontBB[2][8] = { } }; +const int BitTable[64] = { + 63, 30, 3, 32, 25, 41, 22, 33, 15, 50, 42, 13, 11, 53, 19, 34, 61, 29, 2, + 51, 21, 43, 45, 10, 18, 47, 1, 54, 9, 57, 0, 35, 62, 31, 40, 4, 49, 5, 52, + 26, 60, 6, 23, 44, 46, 27, 56, 16, 7, 39, 48, 24, 59, 14, 12, 55, 38, 28, + 58, 20, 37, 17, 36, 8 +}; + extern Bitboard SetMaskBB[65]; extern Bitboard ClearMaskBB[65]; @@ -154,20 +144,12 @@ extern Bitboard BetweenBB[64][64]; extern Bitboard PassedPawnMask[2][64]; extern Bitboard OutpostMask[2][64]; -#if defined(USE_COMPACT_ROOK_ATTACKS) - -extern Bitboard RankAttacks[8][64], FileAttacks[8][64]; - -#else - extern const uint64_t RMult[64]; extern const int RShift[64]; extern Bitboard RMask[64]; extern int RAttackIndex[64]; extern Bitboard RAttacks[0x19000]; -#endif // defined(USE_COMPACT_ROOK_ATTACKS) - extern const uint64_t BMult[64]; extern const int BShift[64]; extern Bitboard BMask[64]; @@ -303,29 +285,24 @@ inline Bitboard ray_bb(Square s, SignedDirection d) { } -/// Functions for computing sliding attack bitboards. rook_attacks_bb(), +/// Functions for computing sliding attack bitboards. rook_attacks_bb(), /// bishop_attacks_bb() and queen_attacks_bb() all take a square and a /// bitboard of occupied squares as input, and return a bitboard representing /// all squares attacked by a rook, bishop or queen on the given square. -#if defined(USE_COMPACT_ROOK_ATTACKS) - -inline Bitboard file_attacks_bb(Square s, Bitboard blockers) { - Bitboard b = (blockers >> square_file(s)) & 0x01010101010100ULL; - return - FileAttacks[square_rank(s)][(b*0xd6e8802041d0c441ULL)>>58] & file_bb(s); -} +#if defined(IS_64BIT) -inline Bitboard rank_attacks_bb(Square s, Bitboard blockers) { - Bitboard b = (blockers >> ((s & 56) + 1)) & 63; - return RankAttacks[square_file(s)][b] & rank_bb(s); +inline Bitboard rook_attacks_bb(Square s, Bitboard blockers) { + Bitboard b = blockers & RMask[s]; + return RAttacks[RAttackIndex[s] + ((b * RMult[s]) >> RShift[s])]; } -inline Bitboard rook_attacks_bb(Square s, Bitboard blockers) { - return file_attacks_bb(s, blockers) | rank_attacks_bb(s, blockers); +inline Bitboard bishop_attacks_bb(Square s, Bitboard blockers) { + Bitboard b = blockers & BMask[s]; + return BAttacks[BAttackIndex[s] + ((b * BMult[s]) >> BShift[s])]; } -#elif defined(USE_32BIT_ATTACKS) +#else // if !defined(IS_64BIT) inline Bitboard rook_attacks_bb(Square s, Bitboard blockers) { Bitboard b = blockers & RMask[s]; @@ -335,17 +312,6 @@ inline Bitboard rook_attacks_bb(Square s, Bitboard blockers) { >> RShift[s])]; } -#else - -inline Bitboard rook_attacks_bb(Square s, Bitboard blockers) { - Bitboard b = blockers & RMask[s]; - return RAttacks[RAttackIndex[s] + ((b * RMult[s]) >> RShift[s])]; -} - -#endif - -#if defined(USE_32BIT_ATTACKS) - inline Bitboard bishop_attacks_bb(Square s, Bitboard blockers) { Bitboard b = blockers & BMask[s]; return BAttacks[BAttackIndex[s] + @@ -354,14 +320,7 @@ inline Bitboard bishop_attacks_bb(Square s, Bitboard blockers) { >> BShift[s])]; } -#else // defined(USE_32BIT_ATTACKS) - -inline Bitboard bishop_attacks_bb(Square s, Bitboard blockers) { - Bitboard b = blockers & BMask[s]; - return BAttacks[BAttackIndex[s] + ((b * BMult[s]) >> BShift[s])]; -} - -#endif // defined(USE_32BIT_ATTACKS) +#endif inline Bitboard queen_attacks_bb(Square s, Bitboard blockers) { return rook_attacks_bb(s, blockers) | bishop_attacks_bb(s, blockers); @@ -423,13 +382,31 @@ inline Bitboard isolated_pawn_mask(Square s) { } +/// first_1() finds the least significant nonzero bit in a nonzero bitboard. + +#if defined(IS_64BIT) + +inline Square first_1(Bitboard b) { + return Square(BitTable[((b & -b) * 0x218a392cd3d5dbfULL) >> 58]); +} + +#else + +inline Square first_1(Bitboard b) { + b ^= (b - 1); + uint32_t fold = int(b) ^ int(b >> 32); + return Square(BitTable[(fold * 0x783a9b23) >> 26]); +} + +#endif + + //// //// Prototypes //// extern void print_bitboard(Bitboard b); extern void init_bitboards(); -extern Square first_1(Bitboard b); extern Square pop_1st_bit(Bitboard *b);