Skip to content

Commit

Permalink
⚡ Use packed evaluation (#697)
Browse files Browse the repository at this point in the history 
* Make use of [Packed evaluation](https://minuskelvin.net/chesswiki/content/packed-eval.html)
* Reduce the amount of arrays stored in memory to the minimum in `EvaluationConstants`
  • Loading branch information
@eduherminio
eduherminio authored Mar 19, 2024
1 parent 53cf80a commit 59e4e18
Show file tree
Hide file tree
Showing 7 changed files with 256 additions and 176 deletions.
9 changes: 6 additions & 3 deletions src/Lynx.Dev/Program.cs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1150,13 +1150,16 @@ static void TestMoveGen(string fen)

static void PieceSquareTables()
{
short[] middleGamePawnTableBlack = EvaluationConstants.MiddleGamePawnTable.Select((_, index) => (short)-EvaluationConstants.MiddleGamePawnTable[index ^ 56]).ToArray();
short[] endGamePawnTableBlack = EvaluationConstants.EndGamePawnTable.Select((_, index) => (short)-EvaluationConstants.EndGamePawnTable[index ^ 56]).ToArray();

PrintBitBoard(EvaluationConstants.MiddleGamePawnTable);
PrintBitBoard(EvaluationConstants.MiddleGamePawnTableBlack);
PrintBitBoard(middleGamePawnTableBlack);

PrintBitBoard(EvaluationConstants.EndGamePawnTable);
PrintBitBoard(EvaluationConstants.EndGamePawnTableBlack);
PrintBitBoard(endGamePawnTableBlack);

static void PrintBitBoard(int[] bitboard)
static void PrintBitBoard<T>(T[] bitboard)
{
for (var rank = 0; rank < 8; ++rank)
{
Expand Down
13 changes: 8 additions & 5 deletions src/Lynx/Configuration.cs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -211,18 +211,21 @@ public sealed class EngineSettings

public sealed class TaperedEvaluationTerm
{
public int MG { get; set; }
[JsonIgnore]
public int PackedEvaluation { get; }

public int EG { get; set; }
public int MG => Utils.UnpackMG(PackedEvaluation);

internal TaperedEvaluationTerm(int singleValue) : this(singleValue, singleValue)
public int EG => Utils.UnpackEG(PackedEvaluation);

internal TaperedEvaluationTerm(int singleValue)
{
PackedEvaluation = Utils.Pack((short)singleValue, (short)singleValue);
}

public TaperedEvaluationTerm(int mg, int eg)
{
MG = mg;
EG = eg;
PackedEvaluation = Utils.Pack((short)mg, (short)eg);
}

public override string ToString()
Expand Down
157 changes: 75 additions & 82 deletions src/Lynx/EvaluationConstants.cs
View file
Original file line number Diff line number Diff line change
@@ -1,5 +1,7 @@
using Lynx.Model;

#pragma warning disable IDE1006 // Naming Styles

namespace Lynx;

public static class EvaluationConstants
Expand All @@ -22,19 +24,19 @@ public static class EvaluationConstants
0, 1, 1, 2, 4, 0
];

public static readonly int[] MiddleGamePieceValues =
internal static readonly short[] MiddleGamePieceValues =
[
+103, +386, +357, +475, +1084, 0,
-103, -386, -357, -475, -1084, 0
];

public static readonly int[] EndGamePieceValues =
internal static readonly short[] EndGamePieceValues =
[
+149, +485, +434, +843, +1560, 0,
-149, -485, -434, -843, -1560, 0
];

public static readonly int[] MiddleGamePawnTable =
internal static readonly short[] MiddleGamePawnTable =
[
0, 0, 0, 0, 0, 0, 0, 0,
-26, -23, -15, -9, -3, 29, 31, -15,
Expand All @@ -46,7 +48,7 @@ public static class EvaluationConstants
0, 0, 0, 0, 0, 0, 0, 0,
];

public static readonly int[] EndGamePawnTable =
internal static readonly short[] EndGamePawnTable =
[
0, 0, 0, 0, 0, 0, 0, 0,
12, 12, 6, -15, 6, 2, -4, -12,
Expand All @@ -58,7 +60,7 @@ public static class EvaluationConstants
0, 0, 0, 0, 0, 0, 0, 0,
];

public static readonly int[] MiddleGameKnightTable =
internal static readonly short[] MiddleGameKnightTable =
[
-153, -23, -52, -32, -12, -21, -9, -98,
-46, -27, -3, 15, 18, 25, -14, -17,
Expand All @@ -70,7 +72,7 @@ public static class EvaluationConstants
-168, -24, -49, -21, -9, -12, -17, -91,
];

public static readonly int[] EndGameKnightTable =
internal static readonly short[] EndGameKnightTable =
[
-72, -61, -13, -13, -10, -28, -55, -93,
-22, -2, 15, 9, 10, 7, -13, -21,
Expand All @@ -82,7 +84,7 @@ public static class EvaluationConstants
-78, -60, -9, -17, -11, -26, -53, -93,
];

public static readonly int[] MiddleGameBishopTable =
internal static readonly short[] MiddleGameBishopTable =
[
-15, 16, -2, -15, -10, -16, -23, 2,
8, 3, 7, -18, 1, -1, 29, -12,
Expand All @@ -94,7 +96,7 @@ public static class EvaluationConstants
10, 20, 12, -29, -13, -21, 1, -12,
];

public static readonly int[] EndGameBishopTable =
internal static readonly short[] EndGameBishopTable =
[
-14, 18, -13, 3, -3, 6, 1, -31,
-5, -8, -4, 5, 4, -10, -2, -16,
Expand All @@ -106,7 +108,7 @@ public static class EvaluationConstants
-7, -12, -7, 7, 8, 9, -2, -22,
];

public static readonly int[] MiddleGameRookTable =
internal static readonly short[] MiddleGameRookTable =
[
-4, -10, -5, 2, 14, 3, 10, 0,
-27, -17, -14, -14, -2, 3, 21, 0,
Expand All @@ -118,7 +120,7 @@ public static class EvaluationConstants
-2, -3, 1, 12, 23, 8, 17, 12,
];

public static readonly int[] EndGameRookTable =
internal static readonly short[] EndGameRookTable =
[
6, 3, 7, -2, -11, 4, 0, -5,
15, 20, 21, 11, 0, -2, -6, 2,
Expand All @@ -130,7 +132,7 @@ public static class EvaluationConstants
1, -3, 2, -8, -18, -4, -9, -15,
];

public static readonly int[] MiddleGameQueenTable =
internal static readonly short[] MiddleGameQueenTable =
[
-15, -10, -5, 9, 3, -32, 14, 1,
0, -10, 7, -2, 2, 6, 22, 51,
Expand All @@ -142,7 +144,7 @@ public static class EvaluationConstants
-11, -11, 5, 11, 6, -39, -12, 28,
];

public static readonly int[] EndGameQueenTable =
internal static readonly short[] EndGameQueenTable =
[
-27, -24, -10, -9, -19, -11, -46, 6,
-22, -13, -28, 0, -2, -17, -48, -5,
Expand All @@ -154,7 +156,7 @@ public static class EvaluationConstants
-15, -18, -17, -2, -9, 21, 13, -9,
];

public static readonly int[] MiddleGameKingTable =
internal static readonly short[] MiddleGameKingTable =
[
34, 55, 30, -72, 12, -58, 44, 57,
-3, -12, -33, -74, -88, -58, -7, 23,
Expand All @@ -166,7 +168,7 @@ public static class EvaluationConstants
49, 82, 43, -55, 25, -47, 58, 70,
];

public static readonly int[] EndGameKingTable =
internal static readonly short[] EndGameKingTable =
[
-85, -49, -22, 4, -36, -3, -41, -96,
-21, 16, 30, 43, 51, 36, 14, -24,
Expand All @@ -180,73 +182,10 @@ public static class EvaluationConstants

#pragma warning restore IDE0055

public static readonly int[] MiddleGamePawnTableBlack = MiddleGamePawnTable.Select((_, index) => -MiddleGamePawnTable[index ^ 56]).ToArray();
public static readonly int[] EndGamePawnTableBlack = EndGamePawnTable.Select((_, index) => -EndGamePawnTable[index ^ 56]).ToArray();

public static readonly int[] MiddleGameKnightTableBlack = MiddleGameKnightTable.Select((_, index) => -MiddleGameKnightTable[index ^ 56]).ToArray();
public static readonly int[] EndGameKnightTableBlack = EndGameKnightTable.Select((_, index) => -EndGameKnightTable[index ^ 56]).ToArray();

public static readonly int[] MiddleGameBishopTableBlack = MiddleGameBishopTable.Select((_, index) => -MiddleGameBishopTable[index ^ 56]).ToArray();
public static readonly int[] EndGameBishopTableBlack = EndGameBishopTable.Select((_, index) => -EndGameBishopTable[index ^ 56]).ToArray();

public static readonly int[] MiddleGameRookTableBlack = MiddleGameRookTable.Select((_, index) => -MiddleGameRookTable[index ^ 56]).ToArray();
public static readonly int[] EndGameRookTableBlack = EndGameRookTable.Select((_, index) => -EndGameRookTable[index ^ 56]).ToArray();

public static readonly int[] MiddleGameQueenTableBlack = MiddleGameQueenTable.Select((_, index) => -MiddleGameQueenTable[index ^ 56]).ToArray();
public static readonly int[] EndGameQueenTableBlack = EndGameQueenTable.Select((_, index) => -EndGameQueenTable[index ^ 56]).ToArray();

public static readonly int[] MiddleGameKingTableBlack = MiddleGameKingTable.Select((_, index) => -MiddleGameKingTable[index ^ 56]).ToArray();
public static readonly int[] EndGameKingTableBlack = EndGameKingTable.Select((_, index) => -EndGameKingTable[index ^ 56]).ToArray();

/// <summary>
/// [12][64]
/// </summary>
public static readonly int[][] MiddleGamePositionalTables =
[
MiddleGamePawnTable,
MiddleGameKnightTable,
MiddleGameBishopTable,
MiddleGameRookTable,
MiddleGameQueenTable,
MiddleGameKingTable,

MiddleGamePawnTableBlack,
MiddleGameKnightTableBlack,
MiddleGameBishopTableBlack,
MiddleGameRookTableBlack,
MiddleGameQueenTableBlack,
MiddleGameKingTableBlack
];

/// <summary>
/// [12][64]
/// </summary>
public static readonly int[][] EndGamePositionalTables =
[
EndGamePawnTable,
EndGameKnightTable,
EndGameBishopTable,
EndGameRookTable,
EndGameQueenTable,
EndGameKingTable,

EndGamePawnTableBlack,
EndGameKnightTableBlack,
EndGameBishopTableBlack,
EndGameRookTableBlack,
EndGameQueenTableBlack,
EndGameKingTableBlack
];

/// <summary>
/// 12x64
/// </summary>
public static readonly int[][] MiddleGameTable = new int[12][];

/// <summary>
/// 12x64
/// </summary>
public static readonly int[][] EndGameTable = new int[12][];
public static readonly int[][] PackedPSQT = new int[12][];

/// <summary>
/// <see cref="Constants.AbsoluteMaxDepth"/> x <see cref="Constants.MaxNumberOfPossibleMovesInAPosition"/>
Expand All @@ -260,14 +199,66 @@ public static class EvaluationConstants

static EvaluationConstants()
{
short[] middleGamePawnTableBlack = MiddleGamePawnTable.Select((_, index) => (short)-MiddleGamePawnTable[index ^ 56]).ToArray();
short[] endGamePawnTableBlack = EndGamePawnTable.Select((_, index) => (short)-EndGamePawnTable[index ^ 56]).ToArray();

short[] middleGameKnightTableBlack = MiddleGameKnightTable.Select((_, index) => (short)-MiddleGameKnightTable[index ^ 56]).ToArray();
short[] endGameKnightTableBlack = EndGameKnightTable.Select((_, index) => (short)-EndGameKnightTable[index ^ 56]).ToArray();

short[] middleGameBishopTableBlack = MiddleGameBishopTable.Select((_, index) => (short)-MiddleGameBishopTable[index ^ 56]).ToArray();
short[] endGameBishopTableBlack = EndGameBishopTable.Select((_, index) => (short)-EndGameBishopTable[index ^ 56]).ToArray();

short[] middleGameRookTableBlack = MiddleGameRookTable.Select((_, index) => (short)-MiddleGameRookTable[index ^ 56]).ToArray();
short[] endGameRookTableBlack = EndGameRookTable.Select((_, index) => (short)-EndGameRookTable[index ^ 56]).ToArray();

short[] middleGameQueenTableBlack = MiddleGameQueenTable.Select((_, index) => (short)-MiddleGameQueenTable[index ^ 56]).ToArray();
short[] EndGameQueenTableBlack = EndGameQueenTable.Select((_, index) => (short)-EndGameQueenTable[index ^ 56]).ToArray();

short[] middleGameKingTableBlack = MiddleGameKingTable.Select((_, index) => (short)-MiddleGameKingTable[index ^ 56]).ToArray();
short[] endGameKingTableBlack = EndGameKingTable.Select((_, index) => (short)-EndGameKingTable[index ^ 56]).ToArray();

short[][] mgPositionalTables =
[
MiddleGamePawnTable,
MiddleGameKnightTable,
MiddleGameBishopTable,
MiddleGameRookTable,
MiddleGameQueenTable,
MiddleGameKingTable,

middleGamePawnTableBlack,
middleGameKnightTableBlack,
middleGameBishopTableBlack,
middleGameRookTableBlack,
middleGameQueenTableBlack,
middleGameKingTableBlack
];

short[][] egPositionalTables =
[
EndGamePawnTable,
EndGameKnightTable,
EndGameBishopTable,
EndGameRookTable,
EndGameQueenTable,
EndGameKingTable,

endGamePawnTableBlack,
endGameKnightTableBlack,
endGameBishopTableBlack,
endGameRookTableBlack,
EndGameQueenTableBlack,
endGameKingTableBlack
];

for (int piece = (int)Piece.P; piece <= (int)Piece.k; ++piece)
{
MiddleGameTable[piece] = new int[64];
EndGameTable[piece] = new int[64];
PackedPSQT[piece] = new int[64];
for (int sq = 0; sq < 64; ++sq)
{
MiddleGameTable[piece][sq] = MiddleGamePieceValues[piece] + MiddleGamePositionalTables[piece][sq];
EndGameTable[piece][sq] = EndGamePieceValues[piece] + EndGamePositionalTables[piece][sq];
PackedPSQT[piece][sq] = Utils.Pack(
(short)(MiddleGamePieceValues[piece] + mgPositionalTables[piece][sq]),
(short)(EndGamePieceValues[piece] + egPositionalTables[piece][sq]));
}
}

Expand Down Expand Up @@ -389,3 +380,5 @@ static EvaluationConstants()
/// </summary>
public const int SingleMoveEvaluation = 200;
}

#pragma warning restore IDE1006 // Naming Styles
Loading

0 comments on commit 59e4e18

Please sign in to comment.