Add small Generics bench to the Put benchmark suite.

benchmarks/Put.hs

 {-# LANGUAGE CPP, ExistentialQuantification #-}
+#ifdef GENERICS
+{-# LANGUAGE DeriveGeneric #-}
+#endif
 
 module Main (main) where
 
@@ -9,6 +12,10 @@ import qualified Data.ByteString as S
 import qualified Data.ByteString.Char8 as C
 import qualified Data.ByteString.Lazy as L
 
+#ifdef GENERICS
+import GHC.Generics
+#endif
+
 import Data.Binary
 import Data.Binary.Put
 import Data.ByteString.Builder as BB
@@ -48,10 +55,33 @@ main = do
       bench "Word64s" $ whnf (run . fromWord64s) word64s,
       bench "Word64s builder" $ whnf (L.length . toLazyByteString . fromWord64sBuilder) word64s,
       bench "[Word64]" $ whnf (run . put) word64s
+
+#ifdef GENERICS
+      , bgroup "Generics" [
+        bench "Struct monoid put" $ whnf (run . fromStructs) structs,
+        bench "Struct put as list" $ whnf (run . put) structs,
+        bench "StructList monoid put" $ whnf (run . fromStructLists) structLists,
+        bench "StructList put as list" $ whnf (run . put) structLists
+      ]
+#endif
     ]
   where
     run = L.length . runPut
 
+#ifdef GENERICS
+data Struct = Struct Word8 Word16 Word32 Word64 deriving Generic
+instance Binary Struct
+
+data StructList = StructList [Struct] deriving Generic
+instance Binary StructList
+
+structs :: [Struct]
+structs = take 10000 $ [ Struct a b 0 0 | a <- [0 .. maxBound], b <- [0 .. maxBound] ]
+
+structLists :: [StructList]
+structLists = replicate 1000 (StructList (take 10 structs))
+#endif
+
 -- Input data
 
 smallIntegers :: [Integer]
@@ -135,3 +165,13 @@ fromWord64s (x:xs) = put x >> fromWord64s xs
 fromWord64sBuilder :: [Word64] -> BB.Builder
 fromWord64sBuilder [] = mempty
 fromWord64sBuilder (x:xs) = BB.word64BE x `mappend` fromWord64sBuilder xs
+
+#ifdef GENERICS
+fromStructs :: [Struct] -> Put
+fromStructs [] = return ()
+fromStructs (x:xs) = put x >> fromStructs xs
+
+fromStructLists :: [StructList] -> Put
+fromStructLists [] = return ()
+fromStructLists (x:xs) = put x >> fromStructLists xs
+#endif

binary.cabal

@@ -136,6 +136,12 @@ benchmark put
   -- build dependencies from using binary source rather than depending on the library
   build-depends: array, containers
   ghc-options: -O2 -Wall
+  if impl(ghc >= 7.2.1)
+    cpp-options: -DGENERICS
+    other-modules: Data.Binary.Generic
+    if impl(ghc <= 7.6)
+      -- prior to ghc-7.4 generics lived in ghc-prim
+      build-depends: ghc-prim
 
 benchmark generics-bench
   type: exitcode-stdio-1.0