X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitboard.h;h=cc039397e3330728022f22c2905891a20849a343;hp=7a39a5009c5571ccf0ef68b5d90792acc353de9b;hb=0ecc920a09f479cb9b568716597e0756da557174;hpb=7b4b65d7a95b3c8b40a11fe5b3efe959d5129008

diff --git a/src/bitboard.h b/src/bitboard.h
index 7a39a500..cc039397 100644
--- a/src/bitboard.h
+++ b/src/bitboard.h
@@ -23,6 +23,13 @@
 
 #include "types.h"
 
+namespace Bitboards {
+
+extern void init();
+extern void print(Bitboard b);
+
+}
+
 CACHE_LINE_ALIGNMENT
 
 extern Bitboard RMasks[64];
@@ -43,7 +50,7 @@ extern Bitboard ThisAndAdjacentFilesBB[8];
 extern Bitboard InFrontBB[2][8];
 extern Bitboard StepAttacksBB[16][64];
 extern Bitboard BetweenBB[64][64];
-extern Bitboard SquaresInFrontMask[2][64];
+extern Bitboard ForwardBB[2][64];
 extern Bitboard PassedPawnMask[2][64];
 extern Bitboard AttackSpanMask[2][64];
 extern Bitboard PseudoAttacks[6][64];
@@ -57,11 +64,26 @@ 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];
+}
+
+
+/// more_than_one() returns true if in 'b' there is more than one bit set
+
+inline bool more_than_one(Bitboard b) {
+  return b & (b - 1);
 }
 
 
@@ -116,48 +138,23 @@ inline Bitboard in_front_bb(Color c, Square s) {
 }
 
 
-/// 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) {
-
-  Bitboard* const Masks  = Pt == ROOK ? RMasks  : BMasks;
-  Bitboard* const Magics = Pt == ROOK ? RMagics : BMagics;
-  unsigned* const Shifts = Pt == ROOK ? RShifts : BShifts;
-
-  if (Is64Bit)
-      return unsigned(((occ & Masks[s]) * Magics[s]) >> Shifts[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];
-}
-
-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)];
-}
-
-
-/// squares_between returns a bitboard representing all squares between
-/// two squares.  For instance, squares_between(SQ_C4, SQ_F7) returns a
-/// bitboard with the bits for square d5 and e6 set.  If s1 and s2 are not
-/// on the same line, file or diagonal, EmptyBoardBB is returned.
+/// between_bb returns a bitboard representing all squares between two squares.
+/// For instance, between_bb(SQ_C4, SQ_F7) returns a bitboard with the bits for
+/// square d5 and e6 set.  If s1 and s2 are not on the same line, file or diagonal,
+/// 0 is returned.
 
-inline Bitboard squares_between(Square s1, Square s2) {
+inline Bitboard between_bb(Square s1, Square s2) {
   return BetweenBB[s1][s2];
 }
 
 
-/// squares_in_front_of takes a color and a square as input, and returns a
-/// bitboard representing all squares along the line in front of the square,
-/// from the point of view of the given color. Definition of the table is:
-/// SquaresInFrontOf[c][s] = in_front_bb(c, s) & file_bb(s)
+/// forward_bb takes a color and a square as input, and returns a bitboard
+/// representing all squares along the line in front of the square, from the
+/// point of view of the given color. Definition of the table is:
+/// ForwardBB[c][s] = in_front_bb(c, s) & file_bb(s)
 
-inline Bitboard squares_in_front_of(Color c, Square s) {
-  return SquaresInFrontMask[c][s];
+inline Bitboard forward_bb(Color c, Square s) {
+  return ForwardBB[c][s];
 }
 
 
@@ -199,6 +196,30 @@ inline Bitboard same_color_squares(Square s) {
 }
 
 
+/// 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) {
+
+  Bitboard* const Masks  = Pt == ROOK ? RMasks  : BMasks;
+  Bitboard* const Magics = Pt == ROOK ? RMagics : BMagics;
+  unsigned* const Shifts = Pt == ROOK ? RShifts : BShifts;
+
+  if (Is64Bit)
+      return unsigned(((occ & Masks[s]) * Magics[s]) >> Shifts[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];
+}
+
+template<PieceType Pt>
+inline Bitboard attacks_bb(Square s, Bitboard occ) {
+  return (Pt == ROOK ? RAttacks : BAttacks)[s][magic_index<Pt>(s, occ)];
+}
+
+
 /// 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.
@@ -208,9 +229,15 @@ 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
 
@@ -219,6 +246,12 @@ 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) {
@@ -230,12 +263,9 @@ 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();
-
 #endif // !defined(BITBOARD_H_INCLUDED)