{-# LANGUAGE CPP, BangPatterns, MagicHash, UnboxedTuples #-}
--
-- (c) The University of Glasgow 2002
--
-- Unboxed mutable Ints

module FastMutInt(
        FastMutInt, newFastMutInt,
        readFastMutInt, writeFastMutInt
  ) where

#define SIZEOF_HSINT  4

import GHC.Exts
# if __GLASGOW_HASKELL__>=612
import GHC.IO     (IO(IO))
#else
import GHC.IOBase (IO(IO))
#endif

data FastMutInt = FastMutInt (MutableByteArray# RealWorld)

newFastMutInt :: IO FastMutInt
newFastMutInt :: IO FastMutInt
newFastMutInt = (State# RealWorld -> (# State# RealWorld, FastMutInt #))
-> IO FastMutInt
forall a. (State# RealWorld -> (# State# RealWorld, a #)) -> IO a
IO ((State# RealWorld -> (# State# RealWorld, FastMutInt #))
 -> IO FastMutInt)
-> (State# RealWorld -> (# State# RealWorld, FastMutInt #))
-> IO FastMutInt
forall a b. (a -> b) -> a -> b
$ \State# RealWorld
s ->
  case Int#
-> State# RealWorld
-> (# State# RealWorld, MutableByteArray# RealWorld #)
forall d. Int# -> State# d -> (# State# d, MutableByteArray# d #)
newByteArray# Int#
size State# RealWorld
s of { (# State# RealWorld
s, MutableByteArray# RealWorld
arr #) ->
  (# State# RealWorld
s, MutableByteArray# RealWorld -> FastMutInt
FastMutInt MutableByteArray# RealWorld
arr #) }
  where !(I# Int#
size) = SIZEOF_HSINT

readFastMutInt :: FastMutInt -> IO Int
readFastMutInt :: FastMutInt -> IO Int
readFastMutInt (FastMutInt MutableByteArray# RealWorld
arr) = (State# RealWorld -> (# State# RealWorld, Int #)) -> IO Int
forall a. (State# RealWorld -> (# State# RealWorld, a #)) -> IO a
IO ((State# RealWorld -> (# State# RealWorld, Int #)) -> IO Int)
-> (State# RealWorld -> (# State# RealWorld, Int #)) -> IO Int
forall a b. (a -> b) -> a -> b
$ \State# RealWorld
s ->
  case MutableByteArray# RealWorld
-> Int# -> State# RealWorld -> (# State# RealWorld, Int# #)
forall d.
MutableByteArray# d -> Int# -> State# d -> (# State# d, Int# #)
readIntArray# MutableByteArray# RealWorld
arr Int#
0# State# RealWorld
s of { (# State# RealWorld
s, Int#
i #) ->
  (# State# RealWorld
s, Int# -> Int
I# Int#
i #) }

writeFastMutInt :: FastMutInt -> Int -> IO ()
writeFastMutInt :: FastMutInt -> Int -> IO ()
writeFastMutInt (FastMutInt MutableByteArray# RealWorld
arr) (I# Int#
i) = (State# RealWorld -> (# State# RealWorld, () #)) -> IO ()
forall a. (State# RealWorld -> (# State# RealWorld, a #)) -> IO a
IO ((State# RealWorld -> (# State# RealWorld, () #)) -> IO ())
-> (State# RealWorld -> (# State# RealWorld, () #)) -> IO ()
forall a b. (a -> b) -> a -> b
$ \State# RealWorld
s ->
  case MutableByteArray# RealWorld
-> Int# -> Int# -> State# RealWorld -> State# RealWorld
forall d.
MutableByteArray# d -> Int# -> Int# -> State# d -> State# d
writeIntArray# MutableByteArray# RealWorld
arr Int#
0# Int#
i State# RealWorld
s of { State# RealWorld
s ->
  (# State# RealWorld
s, () #) }