WebSVN – Games.Chess Giants – Diff – /engine-stockfish/bitboard.cpp

 */
 #include <algorithm>
 #include "bitboard.h"
-#include "bitcount.h"
 #include "misc.h"
+uint8_t PopCnt16[1 << 16];
 int SquareDistance[SQUARE_NB][SQUARE_NB];
 Bitboard  RookMasks  [SQUARE_NB];
 Bitboard  RookMagics [SQUARE_NB];
 Bitboard* RookAttacks[SQUARE_NB];
   unsigned bsf_index(Bitboard b) {
     b ^= b - 1;
     return Is64Bit ? (b * DeBruijn64) >> 58
                    : ((unsigned(b) ^ unsigned(b >> 32)) * DeBruijn32) >> 26;
+  }
+  // popcount16() counts the non-zero bits using SWAR-Popcount algorithm
+  unsigned popcount16(unsigned u) {
+    u -= (u >> 1) & 0x5555U;
+    u = ((u >> 2) & 0x3333U) + (u & 0x3333U);
+    u = ((u >> 4) + u) & 0x0F0FU;
+    return (u * 0x0101U) >> 8;
+  }
+}
-#ifndef USE_BSFQ
+#ifdef NO_BSF
 /// Software fall-back of lsb() and msb() for CPU lacking hardware support
 Square lsb(Bitboard b) {
+  assert(b);
   return BSFTable[bsf_index(b)];
+}
 Square msb(Bitboard b) {
+  assert(b);
   unsigned b32;
   int result = 0;
   if (b > 0xFFFFFFFF)
+  {
+  }
   return Square(result + MSBTable[b32]);
+}
-#endif // ifndef USE_BSFQ
+#endif // ifdef NO_BSF
 /// Bitboards::pretty() returns an ASCII representation of a bitboard suitable
 /// to be printed to standard output. Useful for debugging.
 /// Bitboards::init() initializes various bitboard tables. It is called at
 /// startup and relies on global objects to be already zero-initialized.
 void Bitboards::init() {
+  for (unsigned i = 0; i < (1 << 16); ++i)
+      PopCnt16[i] = (uint8_t) popcount16(i);
   for (Square s = SQ_A1; s <= SQ_H8; ++s)
+  {
       SquareBB[s] = 1ULL << s;
       BSFTable[bsf_index(SquareBB[s])] = s;
                   if (is_ok(to) && distance(s, to) < 3)
                       StepAttacksBB[make_piece(c, pt)][s] |= to;
+              }
-  Square RookDeltas[] = { DELTA_N,  DELTA_E,  DELTA_S,  DELTA_W  };
+  Square RookDeltas[] = { NORTH,  EAST,  SOUTH,  WEST  };
-  Square BishopDeltas[] = { DELTA_NE, DELTA_SE, DELTA_SW, DELTA_NW };
+  Square BishopDeltas[] = { NORTH_EAST, SOUTH_EAST, SOUTH_WEST, NORTH_WEST };
   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)
         // 's' computed on an empty board. The index must be big enough to contain
         // all the attacks for each possible subset of the mask and so is 2 power
         // the number of 1s of the mask. Hence we deduce the size of the shift to
         // apply to the 64 or 32 bits word to get the index.
         masks[s]  = sliding_attack(deltas, s, 0) & ~edges;
-        shifts[s] = (Is64Bit ? 64 : 32) - popcount<Max15>(masks[s]);
+        shifts[s] = (Is64Bit ? 64 : 32) - popcount(masks[s]);
         // Use Carry-Rippler trick to enumerate all subsets of masks[s] and
         // store the corresponding sliding attack bitboard in reference[].
         b = size = 0;
         do {
         // 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] = rng.sparse_rand<Bitboard>();
-            while (popcount<Max15>((magics[s] * masks[s]) >> 56) < 6);
+            while (popcount((magics[s] * masks[s]) >> 56) < 6);
             // A good magic must map every possible occupancy to an index that
             // looks up the correct sliding attack in the attacks[s] database.
             // Note that we build up the database for square 's' as a side
             // effect of verifying the magic.

Subversion Repositories Games.Chess Giants

Games.Chess Giants/engine-stockfish/bitboard.cpp – Rev 96 → 154