Mark all compile-time constants as constexpr.

[stockfish] / src / syzygy / tbprobe.cpp

diff --git a/src/syzygy/tbprobe.cpp b/src/syzygy/tbprobe.cpp
index b50275e30f7e26baaad3bed17db6e5495a64c43d..722679fd948a169ed516a34e39da87c629bafa94 100644 (file)
--- a/src/syzygy/tbprobe.cpp
+++ b/src/syzygy/tbprobe.cpp
@@ -102,7 +102,7 @@ struct LR {
 
 static_assert(sizeof(LR) == 3, "LR tree entry must be 3 bytes");
 
-const int TBPIECES = 6;
+constexpr int TBPIECES = 6;
 
 struct PairsData {
     int flags;
@@ -208,7 +208,7 @@ int MapKK[10][SQUARE_NB]; // [MapA1D1D4][SQUARE_NB]
 bool pawns_comp(Square i, Square j) { return MapPawns[i] < MapPawns[j]; }
 int off_A1H8(Square sq) { return int(rank_of(sq)) - file_of(sq); }
 
-const Value WDL_to_value[] = {
+constexpr Value WDL_to_value[] = {
    -VALUE_MATE + MAX_PLY + 1,
     VALUE_DRAW - 2,
     VALUE_DRAW,
@@ -255,8 +255,8 @@ class HashTable {
     typedef std::pair<WDLEntry*, DTZEntry*> EntryPair;
     typedef std::pair<Key, EntryPair> Entry;
 
-    static const int TBHASHBITS = 10;
-    static const int HSHMAX     = 5;
+    static constexpr int TBHASHBITS = 10;
+    static constexpr int HSHMAX     = 5;
 
     Entry hashTable[1 << TBHASHBITS][HSHMAX];
 
@@ -315,9 +315,9 @@ public:
     TBFile(const std::string& f) {
 
 #ifndef _WIN32
-        const char SepChar = ':';
+        constexpr char SepChar = ':';
 #else
-        const char SepChar = ';';
+        constexpr char SepChar = ';';
 #endif
         std::stringstream ss(Paths);
         std::string path;
@@ -649,7 +649,7 @@ WDLScore map_score(WDLEntry*, File, int value, WDLScore) { return WDLScore(value
 
 int map_score(DTZEntry* entry, File f, int value, WDLScore wdl) {
 
-    const int WDLMap[] = { 1, 3, 0, 2, 0 };
+    constexpr int WDLMap[] = { 1, 3, 0, 2, 0 };
 
     int flags = entry->hasPawns ? entry->pawnTable.file[f].precomp->flags
                                 : entry->pieceTable.precomp->flags;
@@ -682,7 +682,7 @@ int map_score(DTZEntry* entry, File f, int value, WDLScore wdl) {
 template<typename Entry, typename T = typename Ret<Entry>::type>
 T do_probe_table(const Position& pos, Entry* entry, WDLScore wdl, ProbeState* result) {
 
-    const bool IsWDL = std::is_same<Entry, WDLEntry>::value;
+    constexpr bool IsWDL = std::is_same<Entry, WDLEntry>::value;
 
     Square squares[TBPIECES];
     Piece pieces[TBPIECES];
@@ -1081,16 +1081,16 @@ void do_init(Entry& e, T& p, uint8_t* data) {
 
     data++; // First byte stores flags
 
-    const int Sides = IsWDL && (e.key != e.key2) ? 2 : 1;
-    const File MaxFile = e.hasPawns ? FILE_D : FILE_A;
+    const int sides = IsWDL && (e.key != e.key2) ? 2 : 1;
+    const File maxFile = e.hasPawns ? FILE_D : FILE_A;
 
     bool pp = e.hasPawns && e.pawnTable.pawnCount[1]; // Pawns on both sides
 
     assert(!pp || e.pawnTable.pawnCount[0]);
 
-    for (File f = FILE_A; f <= MaxFile; ++f) {
+    for (File f = FILE_A; f <= maxFile; ++f) {
 
-        for (int i = 0; i < Sides; i++)
+        for (int i = 0; i < sides; i++)
             item(p, i, f).precomp = new PairsData();
 
         int order[][2] = { { *data & 0xF, pp ? *(data + 1) & 0xF : 0xF },
@@ -1098,36 +1098,36 @@ void do_init(Entry& e, T& p, uint8_t* data) {
         data += 1 + pp;
 
         for (int k = 0; k < e.pieceCount; ++k, ++data)
-            for (int i = 0; i < Sides; i++)
+            for (int i = 0; i < sides; i++)
                 item(p, i, f).precomp->pieces[k] = Piece(i ? *data >>  4 : *data & 0xF);
 
-        for (int i = 0; i < Sides; ++i)
+        for (int i = 0; i < sides; ++i)
             set_groups(e, item(p, i, f).precomp, order[i], f);
     }
 
     data += (uintptr_t)data & 1; // Word alignment
 
-    for (File f = FILE_A; f <= MaxFile; ++f)
-        for (int i = 0; i < Sides; i++)
+    for (File f = FILE_A; f <= maxFile; ++f)
+        for (int i = 0; i < sides; i++)
             data = set_sizes(item(p, i, f).precomp, data);
 
     if (!IsWDL)
-        data = set_dtz_map(e, p, data, MaxFile);
+        data = set_dtz_map(e, p, data, maxFile);
 
-    for (File f = FILE_A; f <= MaxFile; ++f)
-        for (int i = 0; i < Sides; i++) {
+    for (File f = FILE_A; f <= maxFile; ++f)
+        for (int i = 0; i < sides; i++) {
             (d = item(p, i, f).precomp)->sparseIndex = (SparseEntry*)data;
             data += d->sparseIndexSize * sizeof(SparseEntry);
         }
 
-    for (File f = FILE_A; f <= MaxFile; ++f)
-        for (int i = 0; i < Sides; i++) {
+    for (File f = FILE_A; f <= maxFile; ++f)
+        for (int i = 0; i < sides; i++) {
             (d = item(p, i, f).precomp)->blockLength = (uint16_t*)data;
             data += d->blockLengthSize * sizeof(uint16_t);
         }
 
-    for (File f = FILE_A; f <= MaxFile; ++f)
-        for (int i = 0; i < Sides; i++) {
+    for (File f = FILE_A; f <= maxFile; ++f)
+        for (int i = 0; i < sides; i++) {
             data = (uint8_t*)(((uintptr_t)data + 0x3F) & ~0x3F); // 64 byte alignment
             (d = item(p, i, f).precomp)->data = data;
             data += d->blocksNum * d->sizeofBlock;
@@ -1137,7 +1137,7 @@ void do_init(Entry& e, T& p, uint8_t* data) {
 template<typename Entry>
 void* init(Entry& e, const Position& pos) {
 
-    const bool IsWDL = std::is_same<Entry, WDLEntry>::value;
+    constexpr bool IsWDL = std::is_same<Entry, WDLEntry>::value;
 
     static Mutex mutex;
 
@@ -1158,7 +1158,7 @@ void* init(Entry& e, const Position& pos) {
         b += std::string(popcount(pos.pieces(BLACK, pt)), PieceToChar[pt]);
     }
 
-    const uint8_t TB_MAGIC[][4] = { { 0xD7, 0x66, 0x0C, 0xA5 },
+    constexpr uint8_t TB_MAGIC[][4] = { { 0xD7, 0x66, 0x0C, 0xA5 },
                                     { 0x71, 0xE8, 0x23, 0x5D } };
 
     fname =  (e.key == pos.material_key() ? w + 'v' + b : b + 'v' + w)