{-# LANGUAGE FlexibleContexts #-}
module Map where
import Random
import System.Random.MWC
import Data.Array.Unboxed
import Data.Array.Accelerate as Acc
-- Tests
-- -----
sqAcc, absAcc :: Vector Float -> Acc (Vector Float)
absAcc = Acc.map abs . Acc.use
sqAcc = Acc.map (\x -> x * x) . Acc.use
plusAcc :: Exp Float -> Vector Float -> Acc (Vector Float)
plusAcc alpha = Acc.map (+ alpha) . Acc.use
toUA :: (IArray UArray a, IArray UArray b) => ([a] -> [b]) -> UArray Int a -> UArray Int b
toUA f xs = listArray (bounds xs) $ f (elems xs)
sqRef, absRef :: UArray Int Float -> UArray Int Float
absRef = toUA $ Prelude.map abs
sqRef = toUA $ Prelude.map (\x -> x*x)
plusRef :: Float -> UArray Int Float -> UArray Int Float
plusRef alpha = toUA $ Prelude.map (+alpha)
-- Main
-- ----
run :: String -> Int -> IO (() -> UArray Int Float, () -> Acc (Vector Float))
run alg n = withSystemRandom $ \gen -> do
vec <- randomUArrayR (-1,1) gen n
vec' <- convertUArray vec
alpha <- uniform gen
--
let go f g = return (run_ref f vec, run_acc g vec')
case alg of
"abs" -> go absRef absAcc
"plus" -> go (plusRef alpha) (plusAcc $ constant alpha)
"square" -> go sqRef sqAcc
x -> error $ "unknown variant: " ++ x
where
{-# NOINLINE run_ref #-}
run_ref f xs () = f xs
run_acc f xs () = f xs