X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitboard.h;h=4236d07348d1dfcf97f11f4f681c04ea7fd38385;hp=d2b623f609ea584a1fcee81ff87917179360889e;hb=4ce08482c3b0685691162bfc9115ccc7656674b4;hpb=080a4995a3977a0fe7071e62151dc4d716a13302

diff --git a/src/bitboard.h b/src/bitboard.h
index d2b623f6..4236d073 100644
--- a/src/bitboard.h
+++ b/src/bitboard.h
@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2009 Marco Costalba
+  Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -38,9 +38,6 @@
 
 const Bitboard EmptyBoardBB = 0ULL;
 
-const Bitboard WhiteSquaresBB = 0x55AA55AA55AA55AAULL;
-const Bitboard BlackSquaresBB = 0xAA55AA55AA55AA55ULL;
-
 const Bitboard FileABB = 0x0101010101010101ULL;
 const Bitboard FileBBB = 0x0202020202020202ULL;
 const Bitboard FileCBB = 0x0404040404040404ULL;
@@ -74,8 +71,9 @@ extern Bitboard StepAttackBB[16][64];
 extern Bitboard RayBB[64][8];
 extern Bitboard BetweenBB[64][64];
 
+extern Bitboard SquaresInFrontMask[2][64];
 extern Bitboard PassedPawnMask[2][64];
-extern Bitboard OutpostMask[2][64];
+extern Bitboard AttackSpanMask[2][64];
 
 extern const uint64_t RMult[64];
 extern const int RShift[64];
@@ -127,9 +125,8 @@ inline void do_move_bb(Bitboard *b, Bitboard move_bb) {
   *b ^= move_bb;
 }
 
-/// rank_bb() and file_bb() gives a bitboard containing all squares on a given
-/// file or rank.  It is also possible to pass a square as input to these
-/// functions.
+/// rank_bb() and file_bb() take a file or a square as input, and return
+/// a bitboard representing all squares on the given file or rank.
 
 inline Bitboard rank_bb(Rank r) {
   return RankBB[r];
@@ -156,7 +153,7 @@ inline Bitboard neighboring_files_bb(File f) {
 }
 
 inline Bitboard neighboring_files_bb(Square s) {
-  return neighboring_files_bb(square_file(s));
+  return NeighboringFilesBB[square_file(s)];
 }
 
 
@@ -169,7 +166,7 @@ inline Bitboard this_and_neighboring_files_bb(File f) {
 }
 
 inline Bitboard this_and_neighboring_files_bb(Square s) {
-  return this_and_neighboring_files_bb(square_file(s));
+  return ThisAndNeighboringFilesBB[square_file(s)];
 }
 
 
@@ -195,7 +192,7 @@ inline Bitboard in_front_bb(Color c, Rank r) {
 }
 
 inline Bitboard in_front_bb(Color c, Square s) {
-  return in_front_bb(c, square_rank(s));
+  return InFrontBB[c][square_rank(s)];
 }
 
 
@@ -208,7 +205,7 @@ inline Bitboard behind_bb(Color c, Rank r) {
 }
 
 inline Bitboard behind_bb(Color c, Square s) {
-  return in_front_bb(opposite_color(c), square_rank(s));
+  return InFrontBB[opposite_color(c)][square_rank(s)];
 }
 
 
@@ -274,12 +271,11 @@ inline Bitboard squares_between(Square s1, Square 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.  For instance,
-/// squares_in_front_of(BLACK, SQ_E4) returns a bitboard with the squares
-/// e3, e2 and e1 set.
+/// 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)
 
 inline Bitboard squares_in_front_of(Color c, Square s) {
-  return in_front_bb(c, s) & file_bb(s);
+  return SquaresInFrontMask[c][s];
 }
 
 
@@ -287,33 +283,27 @@ inline Bitboard squares_in_front_of(Color c, Square s) {
 /// behind the square instead of in front of the square.
 
 inline Bitboard squares_behind(Color c, Square s) {
-  return in_front_bb(opposite_color(c), s) & file_bb(s);
+  return SquaresInFrontMask[opposite_color(c)][s];
 }
 
 
 /// passed_pawn_mask takes a color and a square as input, and returns a
 /// bitboard mask which can be used to test if a pawn of the given color on
-/// the given square is a passed pawn.
+/// the given square is a passed pawn. Definition of the table is:
+/// PassedPawnMask[c][s] = in_front_bb(c, s) & this_and_neighboring_files_bb(s)
 
 inline Bitboard passed_pawn_mask(Color c, Square s) {
   return PassedPawnMask[c][s];
 }
 
 
-/// outpost_mask takes a color and a square as input, and returns a bitboard
-/// mask which can be used to test whether a piece on the square can possibly
-/// be driven away by an enemy pawn.
-
-inline Bitboard outpost_mask(Color c, Square s) {
-  return OutpostMask[c][s];
-}
-
-
-/// isolated_pawn_mask takes a square as input, and returns a bitboard mask
-/// which can be used to test whether a pawn on the given square is isolated.
+/// attack_span_mask takes a color and a square as input, and returns a bitboard
+/// representing all squares that can be attacked by a pawn of the given color
+/// when it moves along its file starting from the given square. Definition is:
+/// AttackSpanMask[c][s] = in_front_bb(c, s) & neighboring_files_bb(s);
 
-inline Bitboard isolated_pawn_mask(Square s) {
-  return neighboring_files_bb(s);
+inline Bitboard attack_span_mask(Color c, Square s) {
+  return AttackSpanMask[c][s];
 }
 
 
@@ -323,13 +313,13 @@ inline Bitboard isolated_pawn_mask(Square s) {
 
 #if defined(USE_BSFQ) // Assembly code by Heinz van Saanen
 
-inline Square __attribute__((always_inline)) first_1(Bitboard b) {
+inline Square first_1(Bitboard b) {
   Bitboard dummy;
   __asm__("bsfq %1, %0": "=r"(dummy): "rm"(b) );
   return (Square)(dummy);
 }
 
-inline Square __attribute__((always_inline)) pop_1st_bit(Bitboard* b) {
+inline Square pop_1st_bit(Bitboard* b) {
   const Square s = first_1(*b);
   *b &= ~(1ULL<<s);
   return s;