Differential D5268 Diff 18475 libraries/base/System/Mem/Address.hs

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libraries/base/System/Mem/Address.hs

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		1		{-# LANGUAGE MagicHash #-}
		2
		3		Module System.Mem.Address (
		4		-- * Types
		5		Addr(..),
		6
		7		-- * Address arithmetic
		8		nullAddr, plusAddr, minusAddr, remAddr,
		9
		10		-- * Conversion
		11		addrToInt, addrToPtr, ptrToAddr
		12
		13
		14
		15		) where
		16
		17
		18
		19		import GHC.Base ( Int(..) )
		20		import GHC.Prim
		21
		22		import GHC.Exts (isTrue#)
		23		import GHC.Ptr
		24		import Foreign.Marshal.Utils
		25
		26		import Data.Typeable ( Typeable )
		27		import Data.Data ( Data(..), mkNoRepType )
		28
		29
		30		-- \| A machine address
		31		data Addr = Addr Addr# deriving ( Typeable )
		32
		33		instance Show Addr where
		34		showsPrec _ (Addr a) =
		35		showString "0x" . showHex (fromIntegral (I# (addr2Int# a)) :: Word)
		36
		37		instance Eq Addr where
		38		Addr a# == Addr b# = isTrue# (eqAddr# a# b#)
		39		Addr a# /= Addr b# = isTrue# (neAddr# a# b#)
		40
		41		instance Ord Addr where
		42		Addr a# > Addr b# = isTrue# (gtAddr# a# b#)
		43		Addr a# >= Addr b# = isTrue# (geAddr# a# b#)
		44		Addr a# < Addr b# = isTrue# (ltAddr# a# b#)
		45		Addr a# <= Addr b# = isTrue# (leAddr# a# b#)
		46
		47		instance Data Addr where
		48		toConstr _ = error "toConstr"
		49		gunfold _ _ = error "gunfold"
		50		dataTypeOf _ = mkNoRepType "Data.Primitive.Types.Addr"
		51
		52		-- \| The null address
		53		nullAddr :: Addr
		54		nullAddr = Addr nullAddr#
		55
		56		infixl 6 `plusAddr`, `minusAddr`
		57		infixl 7 `remAddr`
		58
		59		-- \| Offset an address by the given number of bytes
		60		plusAddr :: Addr -> Int -> Addr
		61		plusAddr (Addr a#) (I# i#) = Addr (plusAddr# a# i#)
		62
		63		-- \| Distance in bytes between two addresses. The result is only valid if the
		64		-- difference fits in an 'Int'.
		65		minusAddr :: Addr -> Addr -> Int
		66		minusAddr (Addr a#) (Addr b#) = I# (minusAddr# a# b#)
		67
		68		-- \| The remainder of the address and the integer, in bytes.
		69		remAddr :: Addr -> Int -> Int
		70		remAddr (Addr a#) (I# i#) = I# (remAddr# a# i#)
		71
		72		-- \| Convert an 'Addr' to an 'Int'.
		73		addrToInt :: Addr -> Int
		74		{-# INLINE addrToInt #-}
		75		addrToInt (Addr addr#) = I# (addr2Int# addr#)
		76
		77		-- \| convert `Addr` to `Ptr a`
		78		addrToPtr :: Addr -> Ptr a
		79		addrToPtr (Addr addr#) = Ptr addr#
		80
		81		-- \| convert `Ptr a` to `Addr`
		82		ptrToAddr :: Ptr a -> Addr
		83		ptrToAddr (Ptr p) = Addr p