From 7e95495b35ef84a87fa6be34639a5f96e67972b0 Mon Sep 17 00:00:00 2001
From: Marco Costalba <mcostalba@gmail.com>
Date: Sun, 9 Jun 2013 12:24:43 +0200
Subject: [PATCH] Retire psq_delta()

No functional change.
---
 src/position.cpp | 11 ++++++-----
 src/position.h   |  5 -----
 src/types.h      |  3 ---
 3 files changed, 6 insertions(+), 13 deletions(-)

diff --git a/src/position.cpp b/src/position.cpp
index 1a8c7e00..d145ddfa 100644
--- a/src/position.cpp
+++ b/src/position.cpp
@@ -105,9 +105,9 @@ void init() {
 
 namespace {
 
-/// next_attacker() is an helper function used by see() to locate the least
-/// valuable attacker for the side to move, remove the attacker we just found
-/// from the 'occupied' bitboard and scan for new X-ray attacks behind it.
+// next_attacker() is an helper function used by see() to locate the least
+// valuable attacker for the side to move, remove the attacker we just found
+// from the 'occupied' bitboard and scan for new X-ray attacks behind it.
 
 template<int Pt> FORCE_INLINE
 PieceType next_attacker(const Bitboard* bb, const Square& to, const Bitboard& stmAttackers,
@@ -767,8 +767,9 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI
 
       do_castle(from, to, rfrom, rto);
 
-      st->psqScore += psq_delta(make_piece(us, ROOK), rfrom, rto);
       k ^= Zobrist::psq[us][ROOK][rfrom] ^ Zobrist::psq[us][ROOK][rto];
+      st->psqScore += pieceSquareTable[make_piece(us, ROOK)][rto]
+                    - pieceSquareTable[make_piece(us, ROOK)][rfrom];
   }
 
   if (capture)
@@ -919,7 +920,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI
   }
 
   // Update incremental scores
-  st->psqScore += psq_delta(piece, from, to);
+  st->psqScore += pieceSquareTable[piece][to] - pieceSquareTable[piece][from];
 
   // Set capture piece
   st->capturedType = capture;
diff --git a/src/position.h b/src/position.h
index 7616eadc..8b813587 100644
--- a/src/position.h
+++ b/src/position.h
@@ -169,7 +169,6 @@ public:
 
   // Incremental piece-square evaluation
   Score psq_score() const;
-  Score psq_delta(Piece p, Square from, Square to) const;
   Value non_pawn_material(Color c) const;
 
   // Other properties of the position
@@ -358,10 +357,6 @@ inline Key Position::material_key() const {
   return st->materialKey;
 }
 
-inline Score Position::psq_delta(Piece p, Square from, Square to) const {
-  return pieceSquareTable[p][to] - pieceSquareTable[p][from];
-}
-
 inline Score Position::psq_score() const {
   return st->psqScore;
 }
diff --git a/src/types.h b/src/types.h
index c21b55be..653ebade 100644
--- a/src/types.h
+++ b/src/types.h
@@ -339,9 +339,6 @@ namespace Zobrist {
   void init();
 }
 
-CACHE_LINE_ALIGNMENT
-
-extern Score pieceSquareTable[PIECE_NB][SQUARE_NB];
 extern Value PieceValue[PHASE_NB][PIECE_NB];
 extern int SquareDistance[SQUARE_NB][SQUARE_NB];
 
-- 
2.39.2