Small trivial clean-ups, February 2021

Closes #3329

No functional change

src/Makefile

@@ -1,7 +1,5 @@
 # Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-# Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-# Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
-# Copyright (C) 2015-2019 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
+# Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
 #
 # Stockfish is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by

src/evaluate.cpp

@@ -423,7 +423,6 @@ namespace {
  score += BishopOnKingRing;
 
  int mob = popcount(b & mobilityArea[Us]);
-
  mobility[Us] += MobilityBonus[Pt - 2][mob];
 
  if (Pt == BISHOP || Pt == KNIGHT)

src/movepick.cpp

@@ -99,11 +99,11 @@ void MovePicker::score() {
  static_assert(Type == CAPTURES || Type == QUIETS || Type == EVASIONS, "Wrong type");
 
  for (auto& m : *this)
- if (Type == CAPTURES)
+ if constexpr (Type == CAPTURES)
  m.value = int(PieceValue[MG][pos.piece_on(to_sq(m))]) * 6
  + (*captureHistory)[pos.moved_piece(m)][to_sq(m)][type_of(pos.piece_on(to_sq(m)))];
 
- else if (Type == QUIETS)
+ else if constexpr (Type == QUIETS)
  m.value = (*mainHistory)[pos.side_to_move()][from_to(m)]
  + 2 * (*continuationHistory[0])[pos.moved_piece(m)][to_sq(m)]
  + (*continuationHistory[1])[pos.moved_piece(m)][to_sq(m)]

src/position.cpp

@@ -268,8 +268,8 @@ Position& Position::set(const string& fenStr, bool isChess960, StateInfo* si, Th
  enpassant = pawn_attacks_bb(~sideToMove, st->epSquare) & pieces(sideToMove, PAWN)
  && (pieces(~sideToMove, PAWN) & (st->epSquare + pawn_push(~sideToMove)))
  && !(pieces() & (st->epSquare | (st->epSquare + pawn_push(sideToMove))))
- && (file_of(square<KING>(sideToMove)) == file_of(st->epSquare)
- || !(blockers_for_king(sideToMove) & (st->epSquare + pawn_push(~sideToMove))));
+ && ( file_of(square<KING>(sideToMove)) == file_of(st->epSquare)
+  || !(blockers_for_king(sideToMove) & (st->epSquare + pawn_push(~sideToMove))));
  }
 
  // It's necessary for st->previous to be intialized in this way because legality check relies on its existence
@@ -518,8 +518,8 @@ bool Position::legal(Move m) const {
  // st->previous->blockersForKing consider capsq as empty.
  // If pinned, it has to move along the king ray.
  if (type_of(m) == EN_PASSANT)
- return !(st->previous->blockersForKing[sideToMove] & from) ||
-   aligned(from, to, square<KING>(us));
+ return  !(st->previous->blockersForKing[sideToMove] & from)
+ || aligned(from, to, square<KING>(us));
 
  // Castling moves generation does not check if the castling path is clear of
  // enemy attacks, it is delayed at a later time: now!
@@ -546,8 +546,8 @@ bool Position::legal(Move m) const {
 
  // A non-king move is legal if and only if it is not pinned or it
  // is moving along the ray towards or away from the king.
- return  !(blockers_for_king(us) & from)
-  ||  aligned(from, to, square<KING>(us));
+ return !(blockers_for_king(us) & from)
+ || aligned(from, to, square<KING>(us));
 }
 
 
@@ -657,8 +657,9 @@ bool Position::gives_check(Move m) const {
  // So the King must be in the same rank as fromsq to consider this possibility.
  // st->previous->blockersForKing consider capsq as empty.
  case EN_PASSANT:
- return st->previous->checkersBB || (rank_of(square<KING>(~sideToMove)) == rank_of(from)
- && st->previous->blockersForKing[~sideToMove] & from);
+ return st->previous->checkersBB
+ || ( rank_of(square<KING>(~sideToMove)) == rank_of(from)
+ && st->previous->blockersForKing[~sideToMove] & from);
 
  default: //CASTLING
  {

src/search.cpp

@@ -1025,12 +1025,12 @@ namespace {
  movedPiece = pos.moved_piece(move);
  givesCheck = pos.gives_check(move);
 
- // Indicate PvNodes that will probably fail low if node was searched with non-PV search 
+ // Indicate PvNodes that will probably fail low if node was searched with non-PV search
  // at depth equal or greater to current depth and result of this search was far below alpha
- bool likelyFailLow = PvNode 
- && ttMove 
- && (tte->bound() & BOUND_UPPER) 
- && ttValue < alpha + 200 + 100 * depth 
+ bool likelyFailLow = PvNode
+ && ttMove
+ && (tte->bound() & BOUND_UPPER)
+ && ttValue < alpha + 200 + 100 * depth
  && tte->depth() >= depth;
 
  // Calculate new depth for this move
@@ -1180,8 +1180,8 @@ namespace {
  if (th.marked())
  r++;
 
- // Decrease reduction if position is or has been on the PV 
- // and node is not likely to fail low (~10 Elo)
+ // Decrease reduction if position is or has been on the PV
+ // and node is not likely to fail low. (~10 Elo)
  if (ss->ttPv && !likelyFailLow)
  r -= 2;