X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitboard.h;h=6dd07d5407f85bc431328915c8c459e3a043d7f7;hp=24ae794b68b0f4183087a882cb94ca1bd64cc29c;hb=10e64e05094e75d89baa4495fa867a8a64195bb7;hpb=099b5e45e6fb84c0c6ac9c867e0902e0195d97a5

diff --git a/src/bitboard.h b/src/bitboard.h
index 24ae794b..6dd07d54 100644
--- a/src/bitboard.h
+++ b/src/bitboard.h
@@ -57,11 +57,19 @@ inline Bitboard operator&(Bitboard b, Square s) {
 }
 
 inline Bitboard& operator|=(Bitboard& b, Square s) {
-  return b |= SquareBB[s], b;
+  return b |= SquareBB[s];
 }
 
 inline Bitboard& operator^=(Bitboard& b, Square s) {
-  return b ^= SquareBB[s], b;
+  return b ^= SquareBB[s];
+}
+
+inline Bitboard operator|(Bitboard b, Square s) {
+  return b | SquareBB[s];
+}
+
+inline Bitboard operator^(Bitboard b, Square s) {
+  return b ^ SquareBB[s];
 }
 
 
@@ -116,43 +124,28 @@ inline Bitboard in_front_bb(Color c, Square s) {
 }
 
 
-/// 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.
+/// Functions for computing sliding attack bitboards. Function attacks_bb() takes
+/// a square and a bitboard of occupied squares as input, and returns a bitboard
+/// representing all squares attacked by Pt (bishop or rook) on the given square.
+template<PieceType Pt>
+FORCE_INLINE unsigned magic_index(Square s, Bitboard occ) {
 
-#if defined(IS_64BIT)
+  Bitboard* const Masks  = Pt == ROOK ? RMasks  : BMasks;
+  Bitboard* const Magics = Pt == ROOK ? RMagics : BMagics;
+  unsigned* const Shifts = Pt == ROOK ? RShifts : BShifts;
 
-FORCE_INLINE unsigned r_index(Square s, Bitboard occ) {
-  return unsigned(((occ & RMasks[s]) * RMagics[s]) >> RShifts[s]);
-}
+  if (Is64Bit)
+      return unsigned(((occ & Masks[s]) * Magics[s]) >> Shifts[s]);
 
-FORCE_INLINE unsigned b_index(Square s, Bitboard occ) {
-  return unsigned(((occ & BMasks[s]) * BMagics[s]) >> BShifts[s]);
+  unsigned lo = unsigned(occ) & unsigned(Masks[s]);
+  unsigned hi = unsigned(occ >> 32) & unsigned(Masks[s] >> 32);
+  return (lo * unsigned(Magics[s]) ^ hi * unsigned(Magics[s] >> 32)) >> Shifts[s];
 }
 
-#else // if !defined(IS_64BIT)
-
-FORCE_INLINE unsigned r_index(Square s, Bitboard occ) {
-  unsigned lo = unsigned(occ) & unsigned(RMasks[s]);
-  unsigned hi = unsigned(occ >> 32) & unsigned(RMasks[s] >> 32);
-  return (lo * unsigned(RMagics[s]) ^ hi * unsigned(RMagics[s] >> 32)) >> RShifts[s];
-}
-
-FORCE_INLINE unsigned b_index(Square s, Bitboard occ) {
-  unsigned lo = unsigned(occ) & unsigned(BMasks[s]);
-  unsigned hi = unsigned(occ >> 32) & unsigned(BMasks[s] >> 32);
-  return (lo * unsigned(BMagics[s]) ^ hi * unsigned(BMagics[s] >> 32)) >> BShifts[s];
-}
-
-#endif
-
-inline Bitboard rook_attacks_bb(Square s, Bitboard occ) {
-  return RAttacks[s][r_index(s, occ)];
-}
-
-inline Bitboard bishop_attacks_bb(Square s, Bitboard occ) {
-  return BAttacks[s][b_index(s, occ)];
+template<PieceType Pt>
+inline Bitboard attacks_bb(Square s, Bitboard occ) {
+  Bitboard** const Attacks = Pt == ROOK ? RAttacks : BAttacks;
+  return Attacks[s][magic_index<Pt>(s, occ)];
 }
 
 
@@ -214,6 +207,14 @@ inline Bitboard same_color_squares(Square s) {
 }
 
 
+/// single_bit() returns true if in the 'b' bitboard is set a single bit (or if
+/// b == 0).
+
+inline bool single_bit(Bitboard b) {
+  return !(b & (b - 1));
+}
+
+
 /// first_1() finds the least significant nonzero bit in a nonzero bitboard.
 /// pop_1st_bit() finds and clears the least significant nonzero bit in a
 /// nonzero bitboard.
@@ -223,9 +224,15 @@ inline Bitboard same_color_squares(Square s) {
 #if defined(_MSC_VER) && !defined(__INTEL_COMPILER)
 
 FORCE_INLINE Square first_1(Bitboard b) {
-   unsigned long index;
-   _BitScanForward64(&index, b);
-   return (Square) index;
+  unsigned long index;
+  _BitScanForward64(&index, b);
+  return (Square) index;
+}
+
+FORCE_INLINE Square last_1(Bitboard b) {
+  unsigned long index;
+  _BitScanReverse64(&index, b);
+  return (Square) index;
 }
 #else
 
@@ -234,6 +241,12 @@ FORCE_INLINE Square first_1(Bitboard b) { // Assembly code by Heinz van Saanen
   __asm__("bsfq %1, %0": "=r"(dummy): "rm"(b) );
   return (Square) dummy;
 }
+
+FORCE_INLINE Square last_1(Bitboard b) {
+  Bitboard dummy;
+  __asm__("bsrq %1, %0": "=r"(dummy): "rm"(b) );
+  return (Square) dummy;
+}
 #endif
 
 FORCE_INLINE Square pop_1st_bit(Bitboard* b) {
@@ -245,11 +258,11 @@ FORCE_INLINE Square pop_1st_bit(Bitboard* b) {
 #else // if !defined(USE_BSFQ)
 
 extern Square first_1(Bitboard b);
+extern Square last_1(Bitboard b);
 extern Square pop_1st_bit(Bitboard* b);
 
 #endif
 
-
 extern void print_bitboard(Bitboard b);
 extern void bitboards_init();