Bitboard InFrontBB[2][8];
Bitboard StepAttacksBB[16][64];
Bitboard BetweenBB[64][64];
-Bitboard SquaresInFrontMask[2][64];
+Bitboard ForwardBB[2][64];
Bitboard PassedPawnMask[2][64];
Bitboard AttackSpanMask[2][64];
Bitboard PseudoAttacks[6][64];
return Square(BSFTable[(fold * 0x783A9B23) >> 26]);
}
-// Use type-punning
-union b_union {
-
- Bitboard dummy;
- struct {
-#if defined (BIGENDIAN)
- uint32_t h;
- uint32_t l;
-#else
- uint32_t l;
- uint32_t h;
-#endif
- } b;
-};
-
Square pop_1st_bit(Bitboard* b) {
- const b_union u = *((b_union*)b);
-
- if (u.b.l)
- {
- ((b_union*)b)->b.l = u.b.l & (u.b.l - 1);
- return Square(BSFTable[((u.b.l ^ (u.b.l - 1)) * 0x783A9B23) >> 26]);
- }
-
- ((b_union*)b)->b.h = u.b.h & (u.b.h - 1);
- return Square(BSFTable[((~(u.b.h ^ (u.b.h - 1))) * 0x783A9B23) >> 26]);
+ Bitboard bb = *b;
+ *b = bb & (bb - 1);
+ bb ^= (bb - 1);
+ uint32_t fold = unsigned(bb) ^ unsigned(bb >> 32);
+ return Square(BSFTable[(fold * 0x783A9B23) >> 26]);
}
Square last_1(Bitboard b) {
for (Color c = WHITE; c <= BLACK; c++)
for (Square s = SQ_A1; s <= SQ_H8; s++)
{
- SquaresInFrontMask[c][s] = in_front_bb(c, s) & file_bb(s);
- PassedPawnMask[c][s] = in_front_bb(c, s) & this_and_adjacent_files_bb(file_of(s));
- AttackSpanMask[c][s] = in_front_bb(c, s) & adjacent_files_bb(file_of(s));
+ ForwardBB[c][s] = in_front_bb(c, s) & file_bb(s);
+ PassedPawnMask[c][s] = in_front_bb(c, s) & this_and_adjacent_files_bb(file_of(s));
+ AttackSpanMask[c][s] = in_front_bb(c, s) & adjacent_files_bb(file_of(s));
}
for (Square s1 = SQ_A1; s1 <= SQ_H8; s1++)