X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=Data%2FArray%2FBase.hs;h=32f9fcdbc976fef7299a05de54e36375072ada84;hb=5c556cafe1fef5e4ad6c2cc63c397a026022b7f1;hp=6864362d2481d608e9214f12e888d7a973dfa020;hpb=6d89a2fe861274e66e6fa0a5cdd48b1161b33b75;p=ghc-base.git diff --git a/Data/Array/Base.hs b/Data/Array/Base.hs index 6864362..32f9fcd 100644 --- a/Data/Array/Base.hs +++ b/Data/Array/Base.hs @@ -6,7 +6,7 @@ -- -- Maintainer : libraries@haskell.org -- Stability : experimental --- Portability : non-portable +-- Portability : non-portable (MPTCs, uses Control.Monad.ST) -- -- Basis for IArray and MArray. Not intended for external consumption; -- use IArray or MArray instead. @@ -18,6 +18,8 @@ module Data.Array.Base where import Prelude +import Control.Monad.ST.Lazy ( strictToLazyST ) +import qualified Control.Monad.ST.Lazy as Lazy (ST) import Data.Ix ( Ix, range, index, rangeSize ) import Data.Int import Data.Word @@ -200,48 +202,61 @@ listUArrayST (l,u) es = do -- the type looks like constrained over 's', which runST doesn't -- like. In fact all MArray (STUArray s) instances are polymorphic -- wrt. 's', but runST can't know that. - --- I would like to write a rule for listUArrayST (or listArray or +-- +-- More precisely, we'd like to write this: +-- listUArray :: (forall s. MArray (STUArray s) e (ST s), Ix i) +-- => (i,i) -> [e] -> UArray i e +-- listUArray lu = runST (listUArrayST lu es >>= unsafeFreezeSTUArray) +-- {-# RULES listArray = listUArray +-- Then we could call listUArray at any type 'e' that had a suitable +-- MArray instance. But sadly we can't, because we don't have quantified +-- constraints. Hence the mass of rules below. + +-- I would like also to write a rule for listUArrayST (or listArray or -- whatever) applied to unpackCString#. Unfortunately unpackCString# -- calls seem to be floated out, then floated back into the middle -- of listUArrayST, so I was not able to do this. +#ifdef __GLASGOW_HASKELL__ +type ListUArray e = forall i . Ix i => (i,i) -> [e] -> UArray i e + {-# RULES -"listArray/UArray/Bool" listArray = \lu (es :: [Bool]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) -"listArray/UArray/Char" listArray = \lu (es :: [Char]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) -"listArray/UArray/Int" listArray = \lu (es :: [Int]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) -"listArray/UArray/Word" listArray = \lu (es :: [Word]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) -"listArray/UArray/Ptr" listArray = \lu (es :: [Ptr a]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) -"listArray/UArray/FunPtr" listArray = \lu (es :: [FunPtr a]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) -"listArray/UArray/Float" listArray = \lu (es :: [Float]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) -"listArray/UArray/Double" listArray = \lu (es :: [Double]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) -"listArray/UArray/StablePtr" listArray = \lu (es :: [StablePtr a]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) -"listArray/UArray/Int8" listArray = \lu (es :: [Int8]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) -"listArray/UArray/Int16" listArray = \lu (es :: [Int16]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) -"listArray/UArray/Int32" listArray = \lu (es :: [Int32]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) -"listArray/UArray/Int64" listArray = \lu (es :: [Int64]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) -"listArray/UArray/Word8" listArray = \lu (es :: [Word8]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) -"listArray/UArray/Word16" listArray = \lu (es :: [Word16]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) -"listArray/UArray/Word32" listArray = \lu (es :: [Word32]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) -"listArray/UArray/Word64" listArray = \lu (es :: [Word64]) -> - runST (listUArrayST lu es >>= unsafeFreezeSTUArray) +"listArray/UArray/Bool" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray Bool +"listArray/UArray/Char" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray Char +"listArray/UArray/Int" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray Int +"listArray/UArray/Word" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray Word +"listArray/UArray/Ptr" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray (Ptr a) +"listArray/UArray/FunPtr" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray (FunPtr a) +"listArray/UArray/Float" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray Float +"listArray/UArray/Double" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray Double +"listArray/UArray/StablePtr" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray (StablePtr a) +"listArray/UArray/Int8" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray Int8 +"listArray/UArray/Int16" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray Int16 +"listArray/UArray/Int32" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray Int32 +"listArray/UArray/Int64" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray Int64 +"listArray/UArray/Word8" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray Word8 +"listArray/UArray/Word16" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray Word16 +"listArray/UArray/Word32" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray Word32 +"listArray/UArray/Word64" listArray + = (\lu es -> runST (listUArrayST lu es >>= unsafeFreezeSTUArray)) :: ListUArray Word64 #-} +#endif {-# INLINE (!) #-} -- | Returns the element of an immutable array at the specified index. @@ -1071,6 +1086,14 @@ instance MArray (STArray s) e (ST s) where {-# INLINE unsafeWrite #-} unsafeWrite = ArrST.unsafeWriteSTArray +instance MArray (STArray s) e (Lazy.ST s) where + {-# INLINE newArray #-} + newArray (l,u) e = strictToLazyST (ArrST.newSTArray (l,u) e) + {-# INLINE unsafeRead #-} + unsafeRead arr i = strictToLazyST (ArrST.unsafeReadSTArray arr i) + {-# INLINE unsafeWrite #-} + unsafeWrite arr i e = strictToLazyST (ArrST.unsafeWriteSTArray arr i e) + #ifdef __HUGS__ INSTANCE_TYPEABLE3(STArray,sTArrayTc,"STArray") #endif @@ -1650,14 +1673,20 @@ thawSTUArray (UArray l u arr) = do Note that because the array is possibly not copied, any subsequent modifications made to the mutable version of the array may be - shared with the immutable version. It is safe to use, therefore, if - the immutable version is never referenced again. + shared with the immutable version. It is only safe to use, + therefore, if the immutable array is never referenced again in this + thread, and there is no possibility that it can be also referenced + in another thread. If you use an unsafeThaw/write/unsafeFreeze + sequence in a multi-threaded setting, then you must ensure that + this sequence is atomic with respect to other threads, or a garbage + collector crash may result (because the write may be writing to a + frozen array). The non-copying implementation is supported between certain pairs of array types only; one constraint is that the array types must have identical representations. In GHC, The following pairs of array types have a non-copying O(1) implementation of - 'unsafeFreeze'. Because the optimised versions are enabled by + 'unsafeThaw'. Because the optimised versions are enabled by specialisations, you will need to compile with optimisation (-O) to get them.