From: protonspring <mike@whiteley.org>
Date: Thu, 31 Oct 2019 16:17:46 +0000 (+0100)
Subject: Consolidate pawn_push and up
X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=6f3796adaf44c48cf1353181d386a61a57859b67

Consolidate pawn_push and up

This is a non-functional simplification. Pawn_push and Up are redundant.
If we make up pawn_push, we can use it for all of the Up's and Down's.
In this version, I've also left the Up and Down constants so that there
is no worse readability.

STC
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 23878 W: 5202 L: 5085 D: 13591
http://tests.stockfishchess.org/tests/view/5db5569a0ebc5902d6b14de4

Closes https://github.com/official-stockfish/Stockfish/pull/2378

No functional change
---

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 6bbd72a7..c1640d94 100644
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -213,8 +213,8 @@ namespace {
   void Evaluation<T>::initialize() {
 
     constexpr Color     Them = (Us == WHITE ? BLACK : WHITE);
-    constexpr Direction Up   = (Us == WHITE ? NORTH : SOUTH);
-    constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH);
+    constexpr Direction Up   = pawn_push(Us);
+    constexpr Direction Down = -Up;
     constexpr Bitboard LowRanks = (Us == WHITE ? Rank2BB | Rank3BB : Rank7BB | Rank6BB);
 
     const Square ksq = pos.square<KING>(Us);
@@ -258,7 +258,7 @@ namespace {
   Score Evaluation<T>::pieces() {
 
     constexpr Color     Them = (Us == WHITE ? BLACK : WHITE);
-    constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH);
+    constexpr Direction Down = -pawn_push(Us);
     constexpr Bitboard OutpostRanks = (Us == WHITE ? Rank4BB | Rank5BB | Rank6BB
                                                    : Rank5BB | Rank4BB | Rank3BB);
     const Square* pl = pos.squares<Pt>(Us);
@@ -484,7 +484,7 @@ namespace {
   Score Evaluation<T>::threats() const {
 
     constexpr Color     Them     = (Us == WHITE ? BLACK   : WHITE);
-    constexpr Direction Up       = (Us == WHITE ? NORTH   : SOUTH);
+    constexpr Direction Up       = pawn_push(Us);
     constexpr Bitboard  TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB);
 
     Bitboard b, weak, defended, nonPawnEnemies, stronglyProtected, safe;
@@ -578,7 +578,7 @@ namespace {
   Score Evaluation<T>::passed() const {
 
     constexpr Color     Them = (Us == WHITE ? BLACK : WHITE);
-    constexpr Direction Up   = (Us == WHITE ? NORTH : SOUTH);
+    constexpr Direction Up   = pawn_push(Us);
 
     auto king_proximity = [&](Color c, Square s) {
       return std::min(distance(pos.square<KING>(c), s), 5);
@@ -669,7 +669,7 @@ namespace {
         return SCORE_ZERO;
 
     constexpr Color Them     = (Us == WHITE ? BLACK : WHITE);
-    constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH);
+    constexpr Direction Down = -pawn_push(Us);
     constexpr Bitboard SpaceMask =
       Us == WHITE ? CenterFiles & (Rank2BB | Rank3BB | Rank4BB)
                   : CenterFiles & (Rank7BB | Rank6BB | Rank5BB);
diff --git a/src/movegen.cpp b/src/movegen.cpp
index ef7821e0..0b91582e 100644
--- a/src/movegen.cpp
+++ b/src/movegen.cpp
@@ -56,7 +56,7 @@ namespace {
     constexpr Color     Them     = (Us == WHITE ? BLACK      : WHITE);
     constexpr Bitboard  TRank7BB = (Us == WHITE ? Rank7BB    : Rank2BB);
     constexpr Bitboard  TRank3BB = (Us == WHITE ? Rank3BB    : Rank6BB);
-    constexpr Direction Up       = (Us == WHITE ? NORTH      : SOUTH);
+    constexpr Direction Up       = pawn_push(Us);
     constexpr Direction UpRight  = (Us == WHITE ? NORTH_EAST : SOUTH_WEST);
     constexpr Direction UpLeft   = (Us == WHITE ? NORTH_WEST : SOUTH_EAST);
 
diff --git a/src/pawns.cpp b/src/pawns.cpp
index 84f3d977..3ddf7030 100644
--- a/src/pawns.cpp
+++ b/src/pawns.cpp
@@ -69,7 +69,7 @@ namespace {
   Score evaluate(const Position& pos, Pawns::Entry* e) {
 
     constexpr Color     Them = (Us == WHITE ? BLACK : WHITE);
-    constexpr Direction Up   = (Us == WHITE ? NORTH : SOUTH);
+    constexpr Direction Up   = pawn_push(Us);
 
     Bitboard neighbours, stoppers, support, phalanx, opposed;
     Bitboard lever, leverPush, blocked;