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diff --git a/third_party/bazel/rules_haskell/examples/primitive/Data/Primitive/Addr.hs b/third_party/bazel/rules_haskell/examples/primitive/Data/Primitive/Addr.hs
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+{-# LANGUAGE MagicHash, UnboxedTuples, CPP #-}
+
+-- |
+-- Module      : Data.Primitive.Addr
+-- Copyright   : (c) Roman Leshchinskiy 2009-2012
+-- License     : BSD-style
+--
+-- Maintainer  : Roman Leshchinskiy <rl@cse.unsw.edu.au>
+-- Portability : non-portable
+--
+-- Primitive operations on machine addresses
+--
+
+module Data.Primitive.Addr (
+  -- * Types
+  Addr(..),
+
+  -- * Address arithmetic
+  nullAddr, plusAddr, minusAddr, remAddr,
+
+  -- * Element access
+  indexOffAddr, readOffAddr, writeOffAddr,
+
+  -- * Block operations
+  copyAddr,
+#if __GLASGOW_HASKELL__ >= 708
+  copyAddrToByteArray,
+#endif
+  moveAddr, setAddr,
+
+  -- * Conversion
+  addrToInt
+) where
+
+import Control.Monad.Primitive
+import Data.Primitive.Types
+#if __GLASGOW_HASKELL__ >= 708
+import Data.Primitive.ByteArray
+#endif
+
+import GHC.Base ( Int(..) )
+import GHC.Prim
+
+import GHC.Ptr
+import Foreign.Marshal.Utils
+
+
+-- | The null address
+nullAddr :: Addr
+nullAddr = Addr nullAddr#
+
+infixl 6 `plusAddr`, `minusAddr`
+infixl 7 `remAddr`
+
+-- | Offset an address by the given number of bytes
+plusAddr :: Addr -> Int -> Addr
+plusAddr (Addr a#) (I# i#) = Addr (plusAddr# a# i#)
+
+-- | Distance in bytes between two addresses. The result is only valid if the
+-- difference fits in an 'Int'.
+minusAddr :: Addr -> Addr -> Int
+minusAddr (Addr a#) (Addr b#) = I# (minusAddr# a# b#)
+
+-- | The remainder of the address and the integer.
+remAddr :: Addr -> Int -> Int
+remAddr (Addr a#) (I# i#) = I# (remAddr# a# i#)
+
+-- | Read a value from a memory position given by an address and an offset.
+-- The memory block the address refers to must be immutable. The offset is in
+-- elements of type @a@ rather than in bytes.
+indexOffAddr :: Prim a => Addr -> Int -> a
+{-# INLINE indexOffAddr #-}
+indexOffAddr (Addr addr#) (I# i#) = indexOffAddr# addr# i#
+
+-- | Read a value from a memory position given by an address and an offset.
+-- The offset is in elements of type @a@ rather than in bytes.
+readOffAddr :: (Prim a, PrimMonad m) => Addr -> Int -> m a
+{-# INLINE readOffAddr #-}
+readOffAddr (Addr addr#) (I# i#) = primitive (readOffAddr# addr# i#)
+
+-- | Write a value to a memory position given by an address and an offset.
+-- The offset is in elements of type @a@ rather than in bytes.
+writeOffAddr :: (Prim a, PrimMonad m) => Addr -> Int -> a -> m ()
+{-# INLINE writeOffAddr #-}
+writeOffAddr (Addr addr#) (I# i#) x = primitive_ (writeOffAddr# addr# i# x)
+
+-- | Copy the given number of bytes from the second 'Addr' to the first. The
+-- areas may not overlap.
+copyAddr :: PrimMonad m => Addr         -- ^ destination address
+                        -> Addr         -- ^ source address
+                        -> Int          -- ^ number of bytes
+                        -> m ()
+{-# INLINE copyAddr #-}
+copyAddr (Addr dst#) (Addr src#) n
+  = unsafePrimToPrim $ copyBytes (Ptr dst#) (Ptr src#) n
+
+#if __GLASGOW_HASKELL__ >= 708
+-- | Copy the given number of bytes from the 'Addr' to the 'MutableByteArray'.
+--   The areas may not overlap. This function is only available when compiling
+--   with GHC 7.8 or newer.
+--   
+--   @since 0.6.4.0
+copyAddrToByteArray :: PrimMonad m
+  => MutableByteArray (PrimState m) -- ^ destination
+  -> Int -- ^ offset into the destination array
+  -> Addr -- ^ source
+  -> Int -- ^ number of bytes to copy
+  -> m ()
+{-# INLINE copyAddrToByteArray #-}
+copyAddrToByteArray (MutableByteArray marr) (I# off) (Addr addr) (I# len) =
+  primitive_ $ copyAddrToByteArray# addr marr off len
+#endif
+
+-- | Copy the given number of bytes from the second 'Addr' to the first. The
+-- areas may overlap.
+moveAddr :: PrimMonad m => Addr         -- ^ destination address
+                        -> Addr         -- ^ source address
+                        -> Int          -- ^ number of bytes
+                        -> m ()
+{-# INLINE moveAddr #-}
+moveAddr (Addr dst#) (Addr src#) n
+  = unsafePrimToPrim $ moveBytes (Ptr dst#) (Ptr src#) n
+
+-- | Fill a memory block of with the given value. The length is in
+-- elements of type @a@ rather than in bytes.
+setAddr :: (Prim a, PrimMonad m) => Addr -> Int -> a -> m ()
+{-# INLINE setAddr #-}
+setAddr (Addr addr#) (I# n#) x = primitive_ (setOffAddr# addr# 0# n# x)
+
+-- | Convert an 'Addr' to an 'Int'.
+addrToInt :: Addr -> Int
+{-# INLINE addrToInt #-}
+addrToInt (Addr addr#) = I# (addr2Int# addr#)