feat(xan): Add a benchmark suite

Change-Id: Id31960e7bc2243dfa53dc5e45b09d8253bdef852
Reviewed-on: https://cl.tvl.fyi/c/depot/+/727
Reviewed-by: glittershark <grfn@gws.fyi>

users/glittershark/xanthous/bench/Bench.hs

@@ -0,0 +1,12 @@
+--------------------------------------------------------------------------------
+module Main where
+--------------------------------------------------------------------------------
+import Bench.Prelude
+--------------------------------------------------------------------------------
+import qualified Xanthous.RandomBench
+import qualified Xanthous.Generators.UtilBench
+
+main :: IO ()
+main = defaultMain
+  [ Xanthous.Generators.UtilBench.benchmark
+  ]

users/glittershark/xanthous/bench/Bench/Prelude.hs

@@ -0,0 +1,9 @@
+--------------------------------------------------------------------------------
+module Bench.Prelude
+  ( module Xanthous.Prelude
+  , module Criterion.Main
+  ) where
+--------------------------------------------------------------------------------
+import Xanthous.Prelude
+import Criterion.Main
+--------------------------------------------------------------------------------

users/glittershark/xanthous/bench/Xanthous/Generators/UtilBench.hs

@@ -0,0 +1,37 @@
+--------------------------------------------------------------------------------
+module Xanthous.Generators.UtilBench (benchmark, main) where
+--------------------------------------------------------------------------------
+import           Bench.Prelude
+--------------------------------------------------------------------------------
+import           Data.Array.IArray
+import           Data.Array.Unboxed
+import           System.Random (getStdGen)
+--------------------------------------------------------------------------------
+import           Xanthous.Generators.Util
+import qualified Xanthous.Generators.CaveAutomata as CaveAutomata
+import           Xanthous.Data (Dimensions'(..))
+--------------------------------------------------------------------------------
+
+main :: IO ()
+main = defaultMain [benchmark]
+
+--------------------------------------------------------------------------------
+
+benchmark :: Benchmark
+benchmark = bgroup "Generators.Util"
+  [ bgroup "floodFill"
+    [ env (NFWrapper <$> cells) $ \(NFWrapper ir) ->
+        bench "checkerboard" $ nf (floodFill ir) (1,0)
+    ]
+  ]
+  where
+    cells :: IO Cells
+    cells = CaveAutomata.generate
+      CaveAutomata.defaultParams
+      (Dimensions 50 50)
+      <$> getStdGen
+
+newtype NFWrapper a = NFWrapper a
+
+instance NFData (NFWrapper a) where
+  rnf (NFWrapper x) = x `seq` ()

users/glittershark/xanthous/bench/Xanthous/RandomBench.hs

@@ -0,0 +1,32 @@
+--------------------------------------------------------------------------------
+module Xanthous.RandomBench (benchmark, main) where
+--------------------------------------------------------------------------------
+import Bench.Prelude
+--------------------------------------------------------------------------------
+import Control.Parallel.Strategies
+import Control.Monad.Random
+--------------------------------------------------------------------------------
+import Xanthous.Random
+--------------------------------------------------------------------------------
+
+main :: IO ()
+main = defaultMain [benchmark]
+
+--------------------------------------------------------------------------------
+
+benchmark :: Benchmark
+benchmark = bgroup "Random"
+  [ bgroup "chooseSubset"
+    [ bench "serially" $
+      nf (evalRand $ chooseSubset (0.5 :: Double) [1 :: Int ..1000000])
+         (mkStdGen 1234)
+    ]
+  , bgroup "choose weightedBy"
+    [ bench "serially" $
+      nf (evalRand
+          . choose
+          . weightedBy (\n -> product [n, pred n .. 1])
+          $ [1 :: Int ..1000000])
+         (mkStdGen 1234)
+    ]
+  ]

users/glittershark/xanthous/package.yaml

@@ -137,3 +137,15 @@ tests:
     - tasty-hunit
     - tasty-quickcheck
     - lens-properties
+
+benchmarks:
+  benchmark:
+    main: Bench.hs
+    source-dirs: bench
+    ghc-options:
+    - -threaded
+    - -rtsopts
+    - -with-rtsopts=-N
+    dependencies:
+    - xanthous
+    - criterion

users/glittershark/xanthous/shell.nix

@@ -23,7 +23,7 @@ let
     else packageSet
   );
 
-  drv = haskellPackages.callPackage pkg {};
+  drv = pkgs.haskell.lib.doBenchmark (haskellPackages.callPackage pkg {});
 
   inherit (pkgs.haskell.lib) addBuildTools;
 in