/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
*/
#include <algorithm>
-#include <cstring>
-#include <sstream>
+#include <cstring> // For memset
#include "bitboard.h"
#include "bitcount.h"
-#include "rkiss.h"
+#include "misc.h"
-CACHE_LINE_ALIGNMENT
+Bitboard RookMasks[SQUARE_NB];
+Bitboard RookMagics[SQUARE_NB];
+Bitboard* RookAttacks[SQUARE_NB];
+unsigned RookShifts[SQUARE_NB];
-Bitboard RMasks[SQUARE_NB];
-Bitboard RMagics[SQUARE_NB];
-Bitboard* RAttacks[SQUARE_NB];
-unsigned RShifts[SQUARE_NB];
-
-Bitboard BMasks[SQUARE_NB];
-Bitboard BMagics[SQUARE_NB];
-Bitboard* BAttacks[SQUARE_NB];
-unsigned BShifts[SQUARE_NB];
+Bitboard BishopMasks[SQUARE_NB];
+Bitboard BishopMagics[SQUARE_NB];
+Bitboard* BishopAttacks[SQUARE_NB];
+unsigned BishopShifts[SQUARE_NB];
Bitboard SquareBB[SQUARE_NB];
Bitboard FileBB[FILE_NB];
const uint64_t DeBruijn_64 = 0x3F79D71B4CB0A89ULL;
const uint32_t DeBruijn_32 = 0x783A9B23;
- CACHE_LINE_ALIGNMENT
-
int MS1BTable[256];
Square BSFTable[SQUARE_NB];
- Bitboard RTable[0x19000]; // Storage space for rook attacks
- Bitboard BTable[0x1480]; // Storage space for bishop attacks
+ Bitboard RookTable[0x19000]; // Storage space for rook attacks
+ Bitboard BishopTable[0x1480]; // Storage space for bishop attacks
typedef unsigned (Fn)(Square, Bitboard);
const std::string Bitboards::pretty(Bitboard b) {
- std::ostringstream ss;
+ std::string s = "+---+---+---+---+---+---+---+---+\n";
- for (Rank rank = RANK_8; rank >= RANK_1; --rank)
+ for (Rank r = RANK_8; r >= RANK_1; --r)
{
- ss << "+---+---+---+---+---+---+---+---+" << '\n';
+ for (File f = FILE_A; f <= FILE_H; ++f)
+ s.append(b & make_square(f, r) ? "| X " : "| ");
- for (File file = FILE_A; file <= FILE_H; ++file)
- ss << "| " << (b & (file | rank) ? "X " : " ");
-
- ss << "|\n";
+ s.append("|\n+---+---+---+---+---+---+---+---+\n");
}
- ss << "+---+---+---+---+---+---+---+---+";
- return ss.str();
+
+ return s;
}
void Bitboards::init() {
for (Square s = SQ_A1; s <= SQ_H8; ++s)
- BSFTable[bsf_index(SquareBB[s] = 1ULL << s)] = s;
+ {
+ SquareBB[s] = 1ULL << s;
+ BSFTable[bsf_index(SquareBB[s])] = s;
+ }
for (Bitboard b = 1; b < 256; ++b)
MS1BTable[b] = more_than_one(b) ? MS1BTable[b - 1] : lsb(b);
for (Square s2 = SQ_A1; s2 <= SQ_H8; ++s2)
if (s1 != s2)
{
- SquareDistance[s1][s2] = std::max(file_distance(s1, s2), rank_distance(s1, s2));
+ SquareDistance[s1][s2] = std::max(distance<File>(s1, s2), distance<Rank>(s1, s2));
DistanceRingsBB[s1][SquareDistance[s1][s2] - 1] |= s2;
}
{
Square to = s + Square(c == WHITE ? steps[pt][i] : -steps[pt][i]);
- if (is_ok(to) && square_distance(s, to) < 3)
+ if (is_ok(to) && distance(s, to) < 3)
StepAttacksBB[make_piece(c, pt)][s] |= to;
}
- Square RDeltas[] = { DELTA_N, DELTA_E, DELTA_S, DELTA_W };
- Square BDeltas[] = { DELTA_NE, DELTA_SE, DELTA_SW, DELTA_NW };
+ Square RookDeltas[] = { DELTA_N, DELTA_E, DELTA_S, DELTA_W };
+ Square BishopDeltas[] = { DELTA_NE, DELTA_SE, DELTA_SW, DELTA_NW };
- init_magics(RTable, RAttacks, RMagics, RMasks, RShifts, RDeltas, magic_index<ROOK>);
- init_magics(BTable, BAttacks, BMagics, BMasks, BShifts, BDeltas, magic_index<BISHOP>);
+ init_magics(RookTable, RookAttacks, RookMagics, RookMasks, RookShifts, RookDeltas, magic_index<ROOK>);
+ init_magics(BishopTable, BishopAttacks, BishopMagics, BishopMasks, BishopShifts, BishopDeltas, magic_index<BISHOP>);
for (Square s1 = SQ_A1; s1 <= SQ_H8; ++s1)
{
for (int i = 0; i < 4; ++i)
for (Square s = sq + deltas[i];
- is_ok(s) && square_distance(s, s - deltas[i]) == 1;
+ is_ok(s) && distance(s, s - deltas[i]) == 1;
s += deltas[i])
{
attack |= s;
}
- Bitboard pick_random(RKISS& rk, int booster) {
-
- // Values s1 and s2 are used to rotate the candidate magic of a
- // quantity known to be optimal to quickly find the magics.
- int s1 = booster & 63, s2 = (booster >> 6) & 63;
-
- Bitboard m = rk.rand<Bitboard>();
- m = (m >> s1) | (m << (64 - s1));
- m &= rk.rand<Bitboard>();
- m = (m >> s2) | (m << (64 - s2));
- return m & rk.rand<Bitboard>();
- }
-
-
// init_magics() computes all rook and bishop attacks at startup. Magic
// bitboards are used to look up attacks of sliding pieces. As a reference see
// chessprogramming.wikispaces.com/Magic+Bitboards. In particular, here we
void init_magics(Bitboard table[], Bitboard* attacks[], Bitboard magics[],
Bitboard masks[], unsigned shifts[], Square deltas[], Fn index) {
- int MagicBoosters[][8] = { { 3191, 2184, 1310, 3618, 2091, 1308, 2452, 3996 },
- { 1059, 3608, 605, 3234, 3326, 38, 2029, 3043 } };
- RKISS rk;
+ int seeds[][RANK_NB] = { { 8977, 44560, 54343, 38998, 5731, 95205, 104912, 17020 },
+ { 728, 10316, 55013, 32803, 12281, 15100, 16645, 255 } };
Bitboard occupancy[4096], reference[4096], edges, b;
- int i, size, booster;
+ int i, size;
// attacks[s] is a pointer to the beginning of the attacks table for square 's'
attacks[SQ_A1] = table;
b = size = 0;
do {
occupancy[size] = b;
- reference[size++] = sliding_attack(deltas, s, b);
+ reference[size] = sliding_attack(deltas, s, b);
+
+ if (HasPext)
+ attacks[s][_pext_u64(b, masks[s])] = reference[size];
+
+ size++;
b = (b - masks[s]) & masks[s];
} while (b);
if (s < SQ_H8)
attacks[s + 1] = attacks[s] + size;
- booster = MagicBoosters[Is64Bit][rank_of(s)];
+ if (HasPext)
+ continue;
+
+ PRNG rng(seeds[Is64Bit][rank_of(s)]);
// Find a magic for square 's' picking up an (almost) random number
// until we find the one that passes the verification test.
do {
- do magics[s] = pick_random(rk, booster);
+ do
+ magics[s] = rng.sparse_rand<Bitboard>();
while (popcount<Max15>((magics[s] * masks[s]) >> 56) < 6);
std::memset(attacks[s], 0, size * sizeof(Bitboard));
if (attack && attack != reference[i])
break;
- assert(reference[i] != 0);
+ assert(reference[i]);
attack = reference[i];
}
- } while (i != size);
+ } while (i < size);
}
}
}
projects / stockfish / blobdiff