Files
droidfish/buildSrc/src/main/java/chess/BitBoard.java
2019-03-17 09:11:36 +01:00

383 lines
17 KiB
Java

/*
CuckooChess - A java chess program.
Copyright (C) 2011 Peter Österlund, peterosterlund2@gmail.com
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package chess;
public class BitBoard {
/** Squares attacked by a king on a given square. */
public static final long[] kingAttacks;
public static final long[] knightAttacks;
public static final long[] wPawnAttacks, bPawnAttacks;
// Squares preventing a pawn from being a passed pawn, if occupied by enemy pawn
static final long[] wPawnBlockerMask, bPawnBlockerMask;
public static final long maskAToGFiles = 0x7F7F7F7F7F7F7F7FL;
public static final long maskBToHFiles = 0xFEFEFEFEFEFEFEFEL;
public static final long maskAToFFiles = 0x3F3F3F3F3F3F3F3FL;
public static final long maskCToHFiles = 0xFCFCFCFCFCFCFCFCL;
public static final long[] maskFile = {
0x0101010101010101L,
0x0202020202020202L,
0x0404040404040404L,
0x0808080808080808L,
0x1010101010101010L,
0x2020202020202020L,
0x4040404040404040L,
0x8080808080808080L
};
public static final long maskRow1 = 0x00000000000000FFL;
public static final long maskRow2 = 0x000000000000FF00L;
public static final long maskRow3 = 0x0000000000FF0000L;
public static final long maskRow4 = 0x00000000FF000000L;
public static final long maskRow5 = 0x000000FF00000000L;
public static final long maskRow6 = 0x0000FF0000000000L;
public static final long maskRow7 = 0x00FF000000000000L;
public static final long maskRow8 = 0xFF00000000000000L;
public static final long maskRow1Row8 = 0xFF000000000000FFL;
public static final long maskDarkSq = 0xAA55AA55AA55AA55L;
public static final long maskLightSq = 0x55AA55AA55AA55AAL;
public static final long maskCorners = 0x8100000000000081L;
static {
// Compute king attacks
kingAttacks = new long[64];
for (int sq = 0; sq < 64; sq++) {
long m = 1L << sq;
long mask = (((m >>> 1) | (m << 7) | (m >>> 9)) & maskAToGFiles) |
(((m << 1) | (m << 9) | (m >>> 7)) & maskBToHFiles) |
(m << 8) | (m >>> 8);
kingAttacks[sq] = mask;
}
// Compute knight attacks
knightAttacks = new long[64];
for (int sq = 0; sq < 64; sq++) {
long m = 1L << sq;
long mask = (((m << 6) | (m >>> 10)) & maskAToFFiles) |
(((m << 15) | (m >>> 17)) & maskAToGFiles) |
(((m << 17) | (m >>> 15)) & maskBToHFiles) |
(((m << 10) | (m >>> 6)) & maskCToHFiles);
knightAttacks[sq] = mask;
}
// Compute pawn attacks
wPawnAttacks = new long[64];
bPawnAttacks = new long[64];
wPawnBlockerMask = new long[64];
bPawnBlockerMask = new long[64];
for (int sq = 0; sq < 64; sq++) {
long m = 1L << sq;
long mask = ((m << 7) & maskAToGFiles) | ((m << 9) & maskBToHFiles);
wPawnAttacks[sq] = mask;
mask = ((m >>> 9) & maskAToGFiles) | ((m >>> 7) & maskBToHFiles);
bPawnAttacks[sq] = mask;
int x = Position.getX(sq);
int y = Position.getY(sq);
m = 0;
for (int y2 = y+1; y2 < 8; y2++) {
if (x > 0) m |= 1L << Position.getSquare(x-1, y2);
m |= 1L << Position.getSquare(x , y2);
if (x < 7) m |= 1L << Position.getSquare(x+1, y2);
}
wPawnBlockerMask[sq] = m;
m = 0;
for (int y2 = y-1; y2 >= 0; y2--) {
if (x > 0) m |= 1L << Position.getSquare(x-1, y2);
m |= 1L << Position.getSquare(x , y2);
if (x < 7) m |= 1L << Position.getSquare(x+1, y2);
}
bPawnBlockerMask[sq] = m;
}
}
private final static long[][] rTables;
private final static long[] rMasks;
private final static int[] rBits = { 12, 11, 11, 11, 11, 11, 11, 12,
11, 10, 10, 11, 10, 10, 10, 11,
11, 10, 10, 10, 10, 10, 10, 11,
11, 10, 10, 10, 10, 10, 10, 11,
11, 10, 10, 10, 10, 10, 10, 11,
11, 10, 10, 11, 10, 10, 10, 11,
10, 9, 9, 9, 9, 9, 10, 10,
11, 10, 10, 10, 10, 11, 10, 11 };
private final static long[] rMagics = {
0x19a80065ff2bffffL, 0x3fd80075ffebffffL, 0x4010000df6f6fffeL, 0x0050001faffaffffL,
0x0050028004ffffb0L, 0x7f600280089ffff1L, 0x7f5000b0029ffffcL, 0x5b58004848a7fffaL,
0x002a90005547ffffL, 0x000050007f13ffffL, 0x007fa0006013ffffL, 0x006a9005656fffffL,
0x007f600f600affffL, 0x007ec007e6bfffe2L, 0x007ec003eebffffbL, 0x0071d002382fffdaL,
0x009f803000e7fffaL, 0x00680030008bffffL, 0x00606060004f3ffcL, 0x001a00600bff9ffdL,
0x000d006005ff9fffL, 0x0001806003005fffL, 0x00000300040bfffaL, 0x000192500065ffeaL,
0x00fff112d0006800L, 0x007ff037d000c004L, 0x003fd062001a3ff8L, 0x00087000600e1ffcL,
0x000fff0100100804L, 0x0007ff0100080402L, 0x0003ffe0c0060003L, 0x0001ffd53000d300L,
0x00fffd3000600061L, 0x007fff7f95900040L, 0x003fff8c00600060L, 0x001ffe2587a01860L,
0x000fff3fbf40180cL, 0x0007ffc73f400c06L, 0x0003ff86d2c01405L, 0x0001fffeaa700100L,
0x00fffdfdd8005000L, 0x007fff80ebffb000L, 0x003fffdf603f6000L, 0x001fffe050405000L,
0x000fff400700c00cL, 0x0007ff6007bf600aL, 0x0003ffeebffec005L, 0x0001fffdf3feb001L,
0x00ffff39ff484a00L, 0x007fff3fff486300L, 0x003fff99ffac2e00L, 0x001fff31ff2a6a00L,
0x000fff19ff15b600L, 0x0007fff5fff28600L, 0x0003fffddffbfee0L, 0x0001fff5f63c96a0L,
0x00ffff5dff65cfb6L, 0x007fffbaffd1c5aeL, 0x003fff71ff6cbceaL, 0x001fffd9ffd4756eL,
0x000ffff5fff338e6L, 0x0007fffdfffe24f6L, 0x0003ffef27eebe74L, 0x0001ffff23ff605eL
};
private final static long[][] bTables;
private final static long[] bMasks;
private final static int[] bBits = { 5, 4, 5, 5, 5, 5, 4, 5,
4, 4, 5, 5, 5, 5, 4, 4,
4, 4, 7, 7, 7, 7, 4, 4,
5, 5, 7, 9, 9, 7, 5, 5,
5, 5, 7, 9, 9, 7, 5, 5,
4, 4, 7, 7, 7, 7, 4, 4,
4, 4, 5, 5, 5, 5, 4, 4,
5, 4, 5, 5, 5, 5, 4, 5 };
private final static long[] bMagics = {
0x0006eff5367ff600L, 0x00345835ba77ff2bL, 0x00145f68a3f5dab6L, 0x003a1863fb56f21dL,
0x0012eb6bfe9d93cdL, 0x000d82827f3420d6L, 0x00074bcd9c7fec97L, 0x000034fe99f9ffffL,
0x0000746f8d6717f6L, 0x00003acb32e1a3f7L, 0x0000185daf1ffb8aL, 0x00003a1867f17067L,
0x0000038ee0ccf92eL, 0x000002a2b7ff926eL, 0x000006c9aa93ff14L, 0x00000399b5e5bf87L,
0x00400f342c951ffcL, 0x0020230579ed8ff0L, 0x007b008a0077dbfdL, 0x001d00010c13fd46L,
0x00040022031c1ffbL, 0x000fa00fd1cbff79L, 0x000400a4bc9affdfL, 0x000200085e9cffdaL,
0x002a14560a3dbfbdL, 0x000a0a157b9eafd1L, 0x00060600fd002ffaL, 0x004006000c009010L,
0x001a002042008040L, 0x001a00600fd1ffc0L, 0x000d0ace50bf3f8dL, 0x000183a48434efd1L,
0x001fbd7670982a0dL, 0x000fe24301d81a0fL, 0x0007fbf82f040041L, 0x000040c800008200L,
0x007fe17018086006L, 0x003b7ddf0ffe1effL, 0x001f92f861df4a0aL, 0x000fd713ad98a289L,
0x000fd6aa751e400cL, 0x0007f2a63ae9600cL, 0x0003ff7dfe0e3f00L, 0x000003fd2704ce04L,
0x00007fc421601d40L, 0x007fff5f70900120L, 0x003fa66283556403L, 0x001fe31969aec201L,
0x0007fdfc18ac14bbL, 0x0003fb96fb568a47L, 0x000003f72ea4954dL, 0x00000003f8dc0383L,
0x0000007f3a814490L, 0x00007dc5c9cf62a6L, 0x007f23d3342897acL, 0x003fee36eee1565cL,
0x0003ff3e99fcccc7L, 0x000003ecfcfac5feL, 0x00000003f97f7453L, 0x0000000003f8dc03L,
0x000000007efa8146L, 0x0000007ed3e2ef60L, 0x00007f47243adcd6L, 0x007fb65afabfb3b5L
};
private static final long createPattern(int i, long mask) {
long ret = 0L;
for (int j = 0; ; j++) {
long nextMask = mask & (mask - 1);
long bit = mask ^ nextMask;
if ((i & (1L << j)) != 0)
ret |= bit;
mask = nextMask;
if (mask == 0)
break;
}
return ret;
}
private static final long addRookRays(int x, int y, long occupied, boolean inner) {
long mask = 0;
mask = addRay(mask, x, y, 1, 0, occupied, inner);
mask = addRay(mask, x, y, -1, 0, occupied, inner);
mask = addRay(mask, x, y, 0, 1, occupied, inner);
mask = addRay(mask, x, y, 0, -1, occupied, inner);
return mask;
}
private static final long addBishopRays(int x, int y, long occupied, boolean inner) {
long mask = 0;
mask = addRay(mask, x, y, 1, 1, occupied, inner);
mask = addRay(mask, x, y, -1, -1, occupied, inner);
mask = addRay(mask, x, y, 1, -1, occupied, inner);
mask = addRay(mask, x, y, -1, 1, occupied, inner);
return mask;
}
private static final long addRay(long mask, int x, int y, int dx, int dy,
long occupied, boolean inner) {
int lo = inner ? 1 : 0;
int hi = inner ? 6 : 7;
while (true) {
if (dx != 0) {
x += dx; if ((x < lo) || (x > hi)) break;
}
if (dy != 0) {
y += dy; if ((y < lo) || (y > hi)) break;
}
int sq = Position.getSquare(x, y);
mask |= 1L << sq;
if ((occupied & (1L << sq)) != 0)
break;
}
return mask;
}
static { // Rook magics
rTables = new long[64][];
rMasks = new long[64];
for (int sq = 0; sq < 64; sq++) {
int x = Position.getX(sq);
int y = Position.getY(sq);
rMasks[sq] = addRookRays(x, y, 0L, true);
int tableSize = 1 << rBits[sq];
long[] table = new long[tableSize];
for (int i = 0; i < tableSize; i++) table[i] = -1;
int nPatterns = 1 << Long.bitCount(rMasks[sq]);
for (int i = 0; i < nPatterns; i++) {
long p = createPattern(i, rMasks[sq]);
int entry = (int)((p * rMagics[sq]) >>> (64 - rBits[sq]));
long atks = addRookRays(x, y, p, false);
if (table[entry] == -1) {
table[entry] = atks;
} else if (table[entry] != atks) {
throw new RuntimeException();
}
}
rTables[sq] = table;
}
}
static { // Bishop magics
bTables = new long[64][];
bMasks = new long[64];
for (int sq = 0; sq < 64; sq++) {
int x = Position.getX(sq);
int y = Position.getY(sq);
bMasks[sq] = addBishopRays(x, y, 0L, true);
int tableSize = 1 << bBits[sq];
long[] table = new long[tableSize];
for (int i = 0; i < tableSize; i++) table[i] = -1;
int nPatterns = 1 << Long.bitCount(bMasks[sq]);
for (int i = 0; i < nPatterns; i++) {
long p = createPattern(i, bMasks[sq]);
int entry = (int)((p * bMagics[sq]) >>> (64 - bBits[sq]));
long atks = addBishopRays(x, y, p, false);
if (table[entry] == -1) {
table[entry] = atks;
} else if (table[entry] != atks) {
throw new RuntimeException();
}
}
bTables[sq] = table;
}
}
public static final long bishopAttacks(int sq, long occupied) {
return bTables[sq][(int)(((occupied & bMasks[sq]) * bMagics[sq]) >>> (64 - bBits[sq]))];
}
public static final long rookAttacks(int sq, long occupied) {
return rTables[sq][(int)(((occupied & rMasks[sq]) * rMagics[sq]) >>> (64 - rBits[sq]))];
}
static public final long[][] squaresBetween;
static {
squaresBetween = new long[64][];
for (int sq1 = 0; sq1 < 64; sq1++) {
squaresBetween[sq1] = new long[64];
for (int j = 0; j < 64; j++)
squaresBetween[sq1][j] = 0;
for (int dx = -1; dx <= 1; dx++) {
for (int dy = -1; dy <= 1; dy++) {
if ((dx == 0) && (dy == 0))
continue;
long m = 0;
int x = Position.getX(sq1);
int y = Position.getY(sq1);
while (true) {
x += dx; y += dy;
if ((x < 0) || (x > 7) || (y < 0) || (y > 7))
break;
int sq2 = Position.getSquare(x, y);
squaresBetween[sq1][sq2] = m;
m |= 1L << sq2;
}
}
}
}
}
private static final byte dirTable[] = {
-9, 0, 0, 0, 0, 0, 0, -8, 0, 0, 0, 0, 0, 0, -7,
0, 0, -9, 0, 0, 0, 0, 0, -8, 0, 0, 0, 0, 0, -7, 0,
0, 0, 0, -9, 0, 0, 0, 0, -8, 0, 0, 0, 0, -7, 0, 0,
0, 0, 0, 0, -9, 0, 0, 0, -8, 0, 0, 0, -7, 0, 0, 0,
0, 0, 0, 0, 0, -9, 0, 0, -8, 0, 0, -7, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, -9,-17, -8,-15, -7, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0,-10, -9, -8, -7, -6, 0, 0, 0, 0, 0,
0, -1, -1, -1, -1, -1, -1, -1, 0, 1, 1, 1, 1, 1, 1, 1,
0, 0, 0, 0, 0, 0, 6, 7, 8, 9, 10, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 7, 15, 8, 17, 9, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 7, 0, 0, 8, 0, 0, 9, 0, 0, 0, 0,
0, 0, 0, 0, 7, 0, 0, 0, 8, 0, 0, 0, 9, 0, 0, 0,
0, 0, 0, 7, 0, 0, 0, 0, 8, 0, 0, 0, 0, 9, 0, 0,
0, 0, 7, 0, 0, 0, 0, 0, 8, 0, 0, 0, 0, 0, 9, 0,
0, 7, 0, 0, 0, 0, 0, 0, 8, 0, 0, 0, 0, 0, 0, 9
};
static public final int getDirection(int from, int to) {
int offs = to + (to|7) - from - (from|7) + 0x77;
return dirTable[offs];
}
private static final byte distTable[] = {
7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
0, 7, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7,
0, 7, 6, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 7,
0, 7, 6, 5, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 6, 7,
0, 7, 6, 5, 4, 3, 3, 3, 3, 3, 3, 3, 4, 5, 6, 7,
0, 7, 6, 5, 4, 3, 2, 2, 2, 2, 2, 3, 4, 5, 6, 7,
0, 7, 6, 5, 4, 3, 2, 1, 1, 1, 2, 3, 4, 5, 6, 7,
0, 7, 6, 5, 4, 3, 2, 1, 0, 1, 2, 3, 4, 5, 6, 7,
0, 7, 6, 5, 4, 3, 2, 1, 1, 1, 2, 3, 4, 5, 6, 7,
0, 7, 6, 5, 4, 3, 2, 2, 2, 2, 2, 3, 4, 5, 6, 7,
0, 7, 6, 5, 4, 3, 3, 3, 3, 3, 3, 3, 4, 5, 6, 7,
0, 7, 6, 5, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 6, 7,
0, 7, 6, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 7,
0, 7, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7,
0, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7
};
public static final int getDistance(int from, int to) {
int offs = to + (to|7) - from - (from|7) + 0x77;
return distTable[offs];
}
public static final long southFill(long mask) {
mask |= (mask >>> 8);
mask |= (mask >>> 16);
mask |= (mask >>> 32);
return mask;
}
public static final long northFill(long mask) {
mask |= (mask << 8);
mask |= (mask << 16);
mask |= (mask << 32);
return mask;
}
private static final int trailingZ[] = {
63, 0, 58, 1, 59, 47, 53, 2,
60, 39, 48, 27, 54, 33, 42, 3,
61, 51, 37, 40, 49, 18, 28, 20,
55, 30, 34, 11, 43, 14, 22, 4,
62, 57, 46, 52, 38, 26, 32, 41,
50, 36, 17, 19, 29, 10, 13, 21,
56, 45, 25, 31, 35, 16, 9, 12,
44, 24, 15, 8, 23, 7, 6, 5
};
static public final int numberOfTrailingZeros(long mask) {
return trailingZ[(int)(((mask & -mask) * 0x07EDD5E59A4E28C2L) >>> 58)];
}
}