Remove redundant condition from capture_stage()

Change a non functional promotion check to an assert.

closes https://github.com/official-stockfish/Stockfish/pull/4436

No functional change

diff --git a/src/position.cpp b/src/position.cpp
index 37aa2e9edec97b3812f646d4f38da67168e0b4a5..632a40b5d617658dbb6bb188a4d6e12ca4b96449 100644 (file)
--- a/src/position.cpp
+++ b/src/position.cpp
@@ -569,8 +569,7 @@ bool Position::pseudo_legal(const Move m) const {
                         : MoveList<NON_EVASIONS>(*this).contains(m);
 
   // Is not a promotion, so promotion piece must be empty
-  if (promotion_type(m) - KNIGHT != NO_PIECE_TYPE)
-      return false;
+  assert(promotion_type(m) - KNIGHT == NO_PIECE_TYPE);
 
   // If the 'from' square is not occupied by a piece belonging to the side to
   // move, the move is obviously not legal.

diff --git a/src/position.h b/src/position.h
index 1fc6b3b89c4ab2726b9605d5afc50a326e969bfc..cc606a5ab00af8dcb0d7a6dbed9ec326997b7222 100644 (file)
--- a/src/position.h
+++ b/src/position.h
@@ -393,7 +393,7 @@ inline bool Position::capture(Move m) const {
 // is needed to avoid the generation of duplicate moves.
 inline bool Position::capture_stage(Move m) const {
   assert(is_ok(m));
-  return  capture(m) || (type_of(m) == PROMOTION && promotion_type(m) == QUEEN);
+  return  capture(m) || promotion_type(m) == QUEEN;
 }
 
 inline Piece Position::captured_piece() const {