-{-# OPTIONS_GHC -fparr #-}
+{-# OPTIONS_GHC -fparr -funbox-strict-fields #-}
-----------------------------------------------------------------------------
-- |
fold1P, -- :: (e -> e -> e) -> [:e:] -> e
permuteP, -- :: [:Int:] -> [:e:] -> [:e:]
bpermuteP, -- :: [:Int:] -> [:e:] -> [:e:]
- bpermuteDftP, -- :: [:Int:] -> [:e:] -> [:e:] -> [:e:]
+ dpermuteP, -- :: [:Int:] -> [:e:] -> [:e:] -> [:e:]
crossP, -- :: [:a:] -> [:b:] -> [:(a, b):]
+ crossMapP, -- :: [:a:] -> (a -> [:b:]) -> [:(a, b):]
indexOfP -- :: (a -> Bool) -> [:a:] -> [:Int:]
) where
import GHC.ST ( ST(..), STRep, runST )
import GHC.Exts ( Int#, Array#, Int(I#), MutableArray#, newArray#,
- unsafeFreezeArray#, indexArray#, writeArray# )
+ unsafeFreezeArray#, indexArray#, writeArray#, (<#), (>=#) )
infixl 9 !:
infixr 5 +:+
takeP n = sliceP 0 (n - 1)
dropP :: Int -> [:a:] -> [:a:]
-dropP n a = sliceP (n - 1) (lengthP a - 1) a
+dropP n a = sliceP n (lengthP a - 1) a
splitAtP :: Int -> [:a:] -> ([:a:],[:a:])
splitAtP n xs = (takeP n xs, dropP n xs)
-- (EXPORTED)
--
permuteP :: [:Int:] -> [:e:] -> [:e:]
-permuteP is es = fst $ loop (mapEFL (es!:)) noAL is
+permuteP is es
+ | isLen /= esLen = error "GHC.PArr: arguments must be of the same length"
+ | otherwise = runST (do
+ marr <- newArray isLen noElem
+ permute marr is es
+ mkPArr isLen marr)
+ where
+ noElem = error "GHC.PArr.permuteP: I do not exist!"
+ -- unlike standard Haskell arrays, this value represents an
+ -- internal error
+ isLen = lengthP is
+ esLen = lengthP es
-- permute an array according to the back-permutation vector in the first
-- argument (EXPORTED)
-- the result is undefined
--
bpermuteP :: [:Int:] -> [:e:] -> [:e:]
-bpermuteP is es = error "Prelude.bpermuteP: not implemented yet" -- FIXME
+bpermuteP is es = fst $ loop (mapEFL (es!:)) noAL is
--- permute an array according to the back-permutation vector in the first
+-- permute an array according to the permutation vector in the first
-- argument, which need not be surjective (EXPORTED)
--
--- * any elements in the result that are not covered by the back-permutation
+-- * any elements in the result that are not covered by the permutation
-- vector assume the value of the corresponding position of the third
-- argument
--
-bpermuteDftP :: [:Int:] -> [:e:] -> [:e:] -> [:e:]
-bpermuteDftP is es = error "Prelude.bpermuteDftP: not implemented yet"-- FIXME
+dpermuteP :: [:Int:] -> [:e:] -> [:e:] -> [:e:]
+dpermuteP is es dft
+ | isLen /= esLen = error "GHC.PArr: arguments must be of the same length"
+ | otherwise = runST (do
+ marr <- newArray dftLen noElem
+ trans 0 (isLen - 1) marr dft copyOne noAL
+ permute marr is es
+ mkPArr dftLen marr)
+ where
+ noElem = error "GHC.PArr.permuteP: I do not exist!"
+ -- unlike standard Haskell arrays, this value represents an
+ -- internal error
+ isLen = lengthP is
+ esLen = lengthP es
+ dftLen = lengthP dft
+
+ copyOne e _ = (Just e, noAL)
-- computes the cross combination of two arrays (EXPORTED)
--
zipP x1 x2
-}
+-- |Compute a cross of an array and the arrays produced by the given function
+-- for the elements of the first array.
+--
+crossMapP :: [:a:] -> (a -> [:b:]) -> [:(a, b):]
+crossMapP a f = let
+ bs = mapP f a
+ segd = mapP lengthP bs
+ as = zipWithP replicateP segd a
+ in
+ zipP (concatP as) (concatP bs)
+
+{- The following may seem more straight forward, but the above is very cheap
+ with segmented arrays, as `mapP lengthP', `zipP', and `concatP' are
+ constant time, and `map f' uses the lifted version of `f'.
+
+crossMapP a f = concatP $ mapP (\x -> mapP ((,) x) (f x)) a
+
+ -}
+
-- computes an index array for all elements of the second argument for which
-- the predicate yields `True' (EXPORTED)
--
arr <- mkPArr n' marr
return (arr, acc))
where
- noElem = error "PrelPArr.loopFromTo: I do not exist!"
+ noElem = error "GHC.PArr.loopFromTo: I do not exist!"
-- unlike standard Haskell arrays, this value represents an
-- internal error
return $ marrOff + 1
trans' (arrOff + 1) marrOff' acc'
+-- Permute the given elements into the mutable array.
+--
+permute :: MPArr s e -> [:Int:] -> [:e:] -> ST s ()
+permute marr is es = perm 0
+ where
+ perm i
+ | i == n = return ()
+ | otherwise = writeMPArr marr (is!:i) (es!:i) >> perm (i + 1)
+ where
+ n = lengthP is
+
-- common patterns for using `loop'
--
--
indexPArr :: [:e:] -> Int -> e
{-# INLINE indexPArr #-}
-indexPArr (PArr _ arr#) (I# i#) =
- case indexArray# arr# i# of (# e #) -> e
+indexPArr (PArr n# arr#) (I# i#)
+ | i# >=# 0# && i# <# n# =
+ case indexArray# arr# i# of (# e #) -> e
+ | otherwise = error $ "indexPArr: out of bounds parallel array index; " ++
+ "idx = " ++ show (I# i#) ++ ", arr len = "
+ ++ show (I# n#)
-- encapsulate writing into a mutable array into the `ST' monad
--
writeMPArr :: MPArr s e -> Int -> e -> ST s ()
{-# INLINE writeMPArr #-}
-writeMPArr (MPArr _ marr#) (I# i#) e = ST $ \s# ->
- case writeArray# marr# i# e s# of s'# -> (# s'#, () #)
+writeMPArr (MPArr n# marr#) (I# i#) e
+ | i# >=# 0# && i# <# n# =
+ ST $ \s# ->
+ case writeArray# marr# i# e s# of s'# -> (# s'#, () #)
+ | otherwise = error $ "writeMPArr: out of bounds parallel array index; " ++
+ "idx = " ++ show (I# i#) ++ ", arr len = "
+ ++ show (I# n#)
projects / haskell-directory.git / blobdiff