Added benchmarks

Ordered move generation from high value pieces to lower value ones, this increases the speed drammatically allowing the search to reach depth 6 in ~4 seconds on the initial position

Change-type: minor
Signed-off-by: Giovanni Garufi <[email protected]>

README.md

@@ -1 +1,24 @@
 # hask-chess
+
+## Notes
+
+Changing order of generated moves starting from king, queen and most valueble pieces instead of the other way around has the following huge speedup 
+
+```
+benchmarking initial position/depth: 5 White
+time                 3.446 s    (3.296 s .. 3.554 s)
+                     1.000 R²   (1.000 R² .. 1.000 R²)
+mean                 3.436 s    (3.397 s .. 3.467 s)
+std dev              40.69 ms   (17.53 ms .. 54.18 ms)
+variance introduced by outliers: 19% (moderately inflated)
+```
+to 
+
+```
+benchmarking initial position/depth: 5 White
+time                 470.2 ms   (464.1 ms .. 475.9 ms)
+                     1.000 R²   (1.000 R² .. 1.000 R²)
+mean                 469.3 ms   (466.8 ms .. 470.5 ms)
+std dev              2.301 ms   (89.80 μs .. 2.860 ms)
+variance introduced by outliers: 19% (moderately inflated)
+```

bench/Spec.hs

@@ -0,0 +1,13 @@
+import Criterion.Main
+
+import Fen
+import Board
+import GameTree
+
+main = defaultMain [
+  bgroup "initial position" [
+      bench "depth: 2 White" $ whnf (negamax initialGameState White) 2
+    , bench "depth: 5 White" $ whnf (negamax initialGameState White) 5
+    , bench "depth: 6 White" $ whnf (negamax initialGameState White) 6
+    ]
+  ]

hen.cabal

@@ -0,0 +1,98 @@
+cabal-version: 1.12
+
+-- This file has been generated from package.yaml by hpack version 0.33.0.
+--
+-- see: https://github.com/sol/hpack
+--
+-- hash: 428cef491c676a221e29e7cb0aa5e5191422d48e704d833f35dbe1a4712f85d3
+
+name:           hen
+version:        0.1.0.0
+description:    Please see the README on GitHub at <https://github.com/githubuser/hask-chess#readme>
+homepage:       https://github.com/nazrhom/hen#readme
+bug-reports:    https://github.com/nazrhom/hen/issues
+author:         Giovanni Garufi
+maintainer:     [email protected]
+copyright:      2021 Giovanni Garufi
+license:        BSD3
+license-file:   LICENSE
+build-type:     Simple
+extra-source-files:
+    README.md
+    ChangeLog.md
+
+source-repository head
+  type: git
+  location: https://github.com/nazrhom/hen
+
+library
+  exposed-modules:
+      Board
+      Evaluation
+      Fen
+      GameTree
+      MoveGen
+      Uci
+  other-modules:
+      Paths_hen
+  hs-source-dirs:
+      src
+  build-depends:
+      base >=4.7 && <5
+    , containers
+    , mtl
+    , parsec
+    , vector
+  default-language: Haskell2010
+
+executable hen-exe
+  main-is: Main.hs
+  other-modules:
+      Paths_hen
+  hs-source-dirs:
+      app
+  ghc-options: -threaded -rtsopts -with-rtsopts=-N
+  build-depends:
+      base >=4.7 && <5
+    , containers
+    , hen
+    , mtl
+    , parsec
+    , vector
+  default-language: Haskell2010
+
+test-suite hen-test
+  type: exitcode-stdio-1.0
+  main-is: Spec.hs
+  other-modules:
+      Paths_hen
+  hs-source-dirs:
+      test
+  ghc-options: -threaded -rtsopts -with-rtsopts=-N
+  build-depends:
+      HUnit
+    , base >=4.7 && <5
+    , containers
+    , hen
+    , mtl
+    , parsec
+    , vector
+  default-language: Haskell2010
+
+benchmark hen-bench
+  type: exitcode-stdio-1.0
+  main-is: Spec.hs
+  other-modules:
+      Paths_hen
+  hs-source-dirs:
+      bench
+  ghc-options: -threaded -rtsopts -with-rtsopts=-N
+  build-depends:
+      base >=4.7 && <5
+    , containers
+    , criterion
+    , hen
+    , mtl
+    , parsec
+    , vector
+  default-language: Haskell2010

package.yaml

@@ -25,7 +25,6 @@ dependencies:
 - mtl
 - parsec
 - containers
-- HUnit
 
 library:
   source-dirs: src
@@ -51,3 +50,16 @@ tests:
     - -with-rtsopts=-N
     dependencies:
     - hen
+    - HUnit
+
+benchmarks:
+  hen-bench:
+    main:                Spec.hs
+    source-dirs:         bench
+    ghc-options:
+    - -threaded
+    - -rtsopts
+    - -with-rtsopts=-N
+    dependencies:
+    - hen
+    - criterion

src/MoveGen.hs

@@ -25,12 +25,12 @@ knightMap = foldl (\m k -> M.insert k (go k m) m) M.empty [0..63]
 
 genMoves :: GameState -> Colour -> [Move]
 genMoves gs col =
-     genAllPawnMoves gs col
-  ++ genAllKnightMoves gs col
-  ++ genAllBishopMoves gs col
-  ++ genAllRookMoves gs col
+     genAllKingMoves gs col
   ++ genAllQueenMoves gs col
-  ++ genAllKingMoves gs col
+  ++ genAllRookMoves gs col
+  ++ genAllBishopMoves gs col
+  ++ genAllKnightMoves gs col
+  ++ genAllPawnMoves gs col
 
 applyAll :: GameState -> [Move] -> [GameState]
 applyAll gs moves = map (apply gs) moves