Switch to hardware PEXT

[stockfish] / src / bitboard.h

diff --git a/src/bitboard.h b/src/bitboard.h
index 140867fa94a466272d55be020451b0eb8b012f77..9814268327afdd9c269d728077d1f82770035c87 100644 (file)
--- a/src/bitboard.h
+++ b/src/bitboard.h
@@ -23,8 +23,6 @@
 
 #include "types.h"
 
-extern Bitboard pext(Bitboard b, Bitboard mask);
-
 namespace Bitboards {
 
 void init();
@@ -243,6 +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]);