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[stockfish] / src / bitboard.h

diff --git a/src/bitboard.h b/src/bitboard.h
index 8154f574c6d7baedde7ccea8d50e94005db7fdfb..9814268327afdd9c269d728077d1f82770035c87 100644 (file)
--- 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) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 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
@@ -177,7 +177,7 @@ inline Bitboard in_front_bb(Color c, Rank r) {
 
 /// 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,
+/// square d5 and e6 set.  If s1 and s2 are not on the same rank, file or diagonal,
 /// 0 is returned.
 
 inline Bitboard between_bb(Square s1, Square s2) {
@@ -241,6 +241,9 @@ FORCE_INLINE unsigned magic_index(Square s, Bitboard occ) {
   Bitboard* const Magics = Pt == ROOK ? RMagics : BMagics;
   unsigned* const Shifts = Pt == ROOK ? RShifts : BShifts;
 
+  if (HasPext)
+      return unsigned(_pext_u64(occ, Masks[s]));
+
   if (Is64Bit)
       return unsigned(((occ & Masks[s]) * Magics[s]) >> Shifts[s]);
 
@@ -254,14 +257,14 @@ inline Bitboard attacks_bb(Square s, Bitboard occ) {
   return (Pt == ROOK ? RAttacks : BAttacks)[s][magic_index<Pt>(s, occ)];
 }
 
-inline Bitboard attacks_bb(Piece p, Square s, Bitboard occ) {
+inline Bitboard attacks_bb(Piece pc, Square s, Bitboard occ) {
 
-  switch (type_of(p))
+  switch (type_of(pc))
   {
   case BISHOP: return attacks_bb<BISHOP>(s, occ);
   case ROOK  : return attacks_bb<ROOK>(s, occ);
   case QUEEN : return attacks_bb<BISHOP>(s, occ) | attacks_bb<ROOK>(s, occ);
-  default    : return StepAttacksBB[p][s];
+  default    : return StepAttacksBB[pc][s];
   }
 }
 
@@ -273,15 +276,15 @@ inline Bitboard attacks_bb(Piece p, Square s, Bitboard occ) {
 #  if defined(_MSC_VER) && !defined(__INTEL_COMPILER)
 
 FORCE_INLINE Square lsb(Bitboard b) {
-  unsigned long index;
-  _BitScanForward64(&index, b);
-  return (Square) index;
+  unsigned long idx;
+  _BitScanForward64(&idx, b);
+  return (Square) idx;
 }
 
 FORCE_INLINE Square msb(Bitboard b) {
-  unsigned long index;
-  _BitScanReverse64(&index, b);
-  return (Square) index;
+  unsigned long idx;
+  _BitScanReverse64(&idx, b);
+  return (Square) idx;
 }
 
 #  elif defined(__arm__)
@@ -302,15 +305,15 @@ FORCE_INLINE Square lsb(Bitboard b) {
 #  else
 
 FORCE_INLINE Square lsb(Bitboard b) { // Assembly code by Heinz van Saanen
-  Bitboard index;
-  __asm__("bsfq %1, %0": "=r"(index): "rm"(b) );
-  return (Square) index;
+  Bitboard idx;
+  __asm__("bsfq %1, %0": "=r"(idx): "rm"(b) );
+  return (Square) idx;
 }
 
 FORCE_INLINE Square msb(Bitboard b) {
-  Bitboard index;
-  __asm__("bsrq %1, %0": "=r"(index): "rm"(b) );
-  return (Square) index;
+  Bitboard idx;
+  __asm__("bsrq %1, %0": "=r"(idx): "rm"(b) );
+  return (Square) idx;
 }
 
 #  endif