@@ -4,7 +4,6 @@
44-- |
55-- Module : Data.Binary.Bits.Get
66-- Copyright : (c) Lennart Kolmodin 2010-2011
7−-- (c) Sylvain Henry 2015
87-- License : BSD3-style (see LICENSE)
98--
109-- Maintainer : kolmodin@gmail.com
@@ -60,19 +59,11 @@ module Data.Binary.Bits.Get
6059
6160 -- ** Get bytes
6261 , getBool
63− , getBool#
6462 , getWord8
65− , getWord16
66− , getWord32
67− , getWord64
6863 , getWord16be
6964 , getWord32be
7065 , getWord64be
7166
72− -- ** Skip bits
73− , skipBits
74− , alignByte
75−
7667 -- * Blocks
7768
7869 -- $blocks
@@ -82,41 +73,31 @@ module Data.Binary.Bits.Get
8273 -- ** Read in Blocks
8374 , bool
8475 , word8
85− , word16
86− , word32
87− , word64
8876 , word16be
8977 , word32be
9078 , word64be
9179 , byteString
9280 , Data.Binary.Bits.Get.getByteString
93− , Data.Binary.Bits.Get.getLazyByteString
94− , Data.Binary.Bits.Get.isEmpty
9581
9682 ) where
9783
98−import Data.Binary.Get as B ( Get, getLazyByteString, isEmpty )
99−import Data.Binary.Get.Internal as B ( get, put, ensureN )
100−import Data.Binary.Bits.BitOrder
101−import Data.Binary.Bits.Internal
102−import Data.Binary.Bits.Alignment
84+import Data.Binary.Get as B ( runGet, Get, getByteString )
10385
10486import Data.ByteString as B
105−import qualified Data.ByteString.Lazy as L
10687import Data.ByteString.Unsafe
107−import Foreign.Marshal.Alloc (mallocBytes)
108−import Foreign.Ptr
109−import Foreign.Storable (poke)
110−import System.IO.Unsafe (unsafePerformIO)
11188
11289import Data.Bits
11390import Data.Word
91+
11492import Control.Applicative
115−import Control.Monad (when,foldM_)
11693
11794import Prelude as P
95+
96+#if defined(__GLASGOW_HASKELL__) && !defined(__HADDOCK__)
97+import GHC.Base
11898import GHC.Word
119−import GHC.Base (uncheckedShiftLWord8#, wordToWord8#, Int (..), andWord8#, Word8#, (-#), Int#, xorI#, eqWord8#, TYPE)
99+#endif
100+
120101
121102-- $bitget
122103-- Parse bits using a monad.
@@ -164,121 +145,188 @@ import GHC.Base (uncheckedShiftLWord8#, wordToWord8#, Int (..), andWord8#, Word8
164145--ipv6Header = 'runBitGet' ('block' ipv6headerblock)
165146-- @
166147
167−data S = S {-# UNPACK #-} !ByteString -- Input
168− {-# UNPACK #-} !Int -- Bit offset (0-7)
169− !BitOrder -- Bit order
148+data S = S !ByteString -- Input
149+ !Int -- Bit offset (0-7)
170150 deriving (Show)
171151
172−-- | Increment the current bit offset
152+-- | A block that will be read with only one boundry check. Needs to know the
153+-- number of bits in advance.
154+data Block a = Block !Int (S -> a)
155+
156+instance Functor Block where
157+ fmap f (Block i p) = Block i (\s -> f (p s))
158+
159+instance Applicative Block where
160+ pure a = Block 0 (\_ -> a)
161+ (Block i p) <*> (Block j q) = Block (i+j) (\s -> p s $ q (incS i s))
162+ (Block i _) *> (Block j q) = Block (i+j) (q . incS i)
163+ (Block i p) <* (Block j _) = Block (i+j) p
164+
165+-- | Get a block. Will be read with one single boundry check, and
166+-- therefore requires a statically known number of bits.
167+-- Build blocks using 'bool', 'word8', 'word16be', 'word32be', 'word64be',
168+-- 'byteString' and 'Applicative'.
169+block :: Block a -> BitGet a
170+block (Block i p) = do
171+ ensureBits i
172+ modifyState (\s -> (incS i s, p s))
173+
174+
173175incS :: Int -> S -> S
174−incS o (S bs n bo) = S (unsafeDrop d bs) n' bo
175− where
176− !o' = (n+o)
177− !d = byte_offset o'
178− !n' = bit_offset o'
176+incS o (S bs n) =
177+ let !o' = (n+o)
178+ !d = o' `shiftR` 3
179+ !n' = o' .&. make_mask 3
180+ in S (unsafeDrop d bs) n'
181+
182+-- | make_mask 3 = 00000111
183+make_mask :: Bits a => Int -> a
184+make_mask n = (1 `shiftL` fromIntegral n) - 1
185+{-# SPECIALIZE make_mask :: Int -> Int #-}
186+{-# SPECIALIZE make_mask :: Int -> Word #-}
187+{-# SPECIALIZE make_mask :: Int -> Word8 #-}
188+{-# SPECIALIZE make_mask :: Int -> Word16 #-}
189+{-# SPECIALIZE make_mask :: Int -> Word32 #-}
190+{-# SPECIALIZE make_mask :: Int -> Word64 #-}
191+
192+bit_offset :: Int -> Int
193+bit_offset n = make_mask 3 .&. n
194+
195+byte_offset :: Int -> Int
196+byte_offset n = n `shiftR` 3
179197
180−-- | Read a single bit
181198readBool :: S -> Bool
182−readBool (S bs o bo) = case bo of
183− BB -> testBit (unsafeHead bs) (7-o)
184− BL -> testBit (unsafeHead bs) (7-o)
185− LL -> testBit (unsafeHead bs) o
186− LB -> testBit (unsafeHead bs) o
187−
188−-- | Read a single bit
189−readBool# :: S -> Int
190−readBool# (S bs (I# o) bo) = case bo of
191− BB -> testBit# (7# -# o)
192− BL -> testBit# (7# -# o)
193− LL -> testBit# o
194− LB -> testBit# o
195− where
196− !(W8# w) = unsafeHead bs
197− testBit# n = I# (((w `andWord8#` (wordToWord8# 1## `uncheckedShiftLWord8#` n)) `eqWord8#` wordToWord8# 0##) `xorI#` 1#)
198−
199−
200−-- | Extract a range of bits from (ws :: ByteString)
201−--
202−-- Constraint: 8 * (length ws -1 ) < o+n <= 8 * length ws
203−extract :: (Num a, FastBits a) => BitOrder -> ByteString -> Int -> Int -> a
204−extract bo bs o n
205− | n == 0 = 0
206− | B.length bs == 0 = error "Empty ByteString"
207− | otherwise = rev . mask n . foldlWithIndex' f 0 $ bs
208− where
209− -- B.foldl' with index
210− foldlWithIndex' op b = fst . B.foldl' g (b,0)
211− where g (b',i) w = (op b' w i, (i+1))
212−
213− -- 'or' correctly shifted words
214− f b w i = b .|. (fromIntegral w `fastShift` off i)
215−
216− -- co-offset
217− r = B.length bs * 8 - (o + n)
218−
219− -- shift offset depending on the byte position (0..B.length-1)
220− off i = case bo of
221− LL -> 8*i - o
222− LB -> 8*i - o
223− BB -> (B.length bs -1 - i) * 8 - r
224− BL -> (B.length bs -1 - i) * 8 - r
225−
226− -- reverse bits if necessary
227− rev = case bo of
228− LB -> reverseBits n
229− BL -> reverseBits n
230− BB -> id
231− LL -> id
232−
233−
234−-- | Generic readWord
235−readWord :: (Num a, FastBits a) => Int -> S -> a
236−readWord n (S bs o bo)
237− | n == 0 = 0
238− | otherwise = extract bo (unsafeTake nbytes bs) o n
239− where nbytes = byte_offset (o+n+7)
240−
241−-- | Check that the number of bits to read is not greater than the first parameter
242−{-# INLINE readWordChecked #-}
243−readWordChecked :: (Num a, FastBits a) => Int -> Int -> S -> a
244−readWordChecked m n s
245− | n > m = error $ "Tried to read more than " ++ show m ++ " bits (" ++ show n ++")"
246− | otherwise = readWord n s
247−
248−-- | Read the given number of bytes and return them in Big-Endian order
249−--
250−-- Examples:
251−-- BB: xxxABCDE FGHIJKLM NOPxxxxx -> ABCDEFGH IJKLMNOP
252−-- LL: LMNOPxxx DEFGHIJK xxxxxABC -> ABCDEFGH IJKLMNOP
253−-- BL: xxxPONML KJIHGFED CBAxxxxx -> ABCDEFGH IJKLMNOP
254−-- LB: EDCBAxxx MLKJIHGF xxxxxPON -> ABCDEFGH IJKLMNOP
199+readBool (S bs n) = testBit (unsafeHead bs) (7-n)
200+
201+readWord8 :: Int -> S -> Word8
202+readWord8 n (S bs o)
203+ -- no bits at all, return 0
204+ | n == 0 = 0
205+
206+ -- all bits are in the same byte
207+ -- we just need to shift and mask them right
208+ | n <= 8 - o = let w = unsafeHead bs
209+ m = make_mask n
210+ w' = (w `shiftr_w8` (8 - o - n)) .&. m
211+ in w'
212+
213+ -- the bits are in two different bytes
214+ -- make a word16 using both bytes, and then shift and mask
215+ | n <= 8 = let w = (fromIntegral (unsafeHead bs) `shiftl_w16` 8) .|.
216+ (fromIntegral (unsafeIndex bs 1))
217+ m = make_mask n
218+ w' = (w `shiftr_w16` (16 - o - n)) .&. m
219+ in fromIntegral w'
220+
221+
222+readWord16be :: Int -> S -> Word16
223+readWord16be n s@(S bs o)
224+
225+ -- 8 or fewer bits, use readWord8
226+ | n <= 8 = fromIntegral (readWord8 n s)
227+
228+ -- handle 9 or more bits, stored in two bytes
229+
230+ -- no offset, plain and simple 16 bytes
231+ | o == 0 && n == 16 = let msb = fromIntegral (unsafeHead bs)
232+ lsb = fromIntegral (unsafeIndex bs 1)
233+ w = (msb `shiftl_w16` 8) .|. lsb
234+ in w
235+
236+ -- no offset, but not full 16 bytes
237+ | o == 0 = let msb = fromIntegral (unsafeHead bs)
238+ lsb = fromIntegral (unsafeIndex bs 1)
239+ w = (msb `shiftl_w16` (n-8)) .|. (lsb `shiftr_w16` (16-n))
240+ in w
241+
242+ -- with offset, and n=9-16
243+ | n <= 16 = readWithOffset s shiftl_w16 shiftr_w16 n
244+
245+ | otherwise = error "readWord16be: tried to read more than 16 bits"
246+
247+readWord32be :: Int -> S -> Word32
248+readWord32be n s@(S _ o)
249+ -- 8 or fewer bits, use readWord8
250+ | n <= 8 = fromIntegral (readWord8 n s)
251+
252+ -- 16 or fewer bits, use readWord16be
253+ | n <= 16 = fromIntegral (readWord16be n s)
254+
255+ | o == 0 = readWithoutOffset s shiftl_w32 shiftr_w32 n
256+
257+ | n <= 32 = readWithOffset s shiftl_w32 shiftr_w32 n
258+
259+ | otherwise = error "readWord32be: tried to read more than 32 bits"
260+
261+
262+readWord64be :: Int -> S -> Word64
263+readWord64be n s@(S _ o)
264+ -- 8 or fewer bits, use readWord8
265+ | n <= 8 = fromIntegral (readWord8 n s)
266+
267+ -- 16 or fewer bits, use readWord16be
268+ | n <= 16 = fromIntegral (readWord16be n s)
269+
270+ | o == 0 = readWithoutOffset s shiftl_w64 shiftr_w64 n
271+
272+ | n <= 64 = readWithOffset s shiftl_w64 shiftr_w64 n
273+
274+ | otherwise = error "readWord64be: tried to read more than 64 bits"
275+
276+
255277readByteString :: Int -> S -> ByteString
256−readByteString n (S bs o bo) =
257− let
258− bs' = unsafeTake (n+1) bs
259− bs'' = unsafeTake n bs
260− rev = B.map (reverseBits 8)
261− in case (o,bo) of
262− (0,BB) -> bs''
263− (0,LL) -> B.reverse bs''
264− (0,LB) -> rev bs''
265− (0,BL) -> rev . B.reverse $ bs''
266− (_,LL) -> readByteString n (S (B.reverse bs') (8-o) BB)
267− (_,BL) -> rev . B.reverse $ readByteString n (S bs' o BB)
268− (_,LB) -> rev . B.reverse $ readByteString n (S bs' o LL)
269− (_,BB) -> unsafePerformIO $ do
270− let len = n+1
271− ptr <- mallocBytes len
272− let f r i = do
273− let
274− w = unsafeIndex bs (len-i)
275− w' = (w `fastShiftL` o) .|. r
276− r' = w `fastShiftR` (8-o)
277− poke (ptr `plusPtr` (len-i)) w'
278− return r'
279− foldM_ f 0 [1..len]
280− unsafeInit <$> unsafePackMallocCStringLen (ptr,len)
278+readByteString n s@(S bs o)
279+ -- no offset, easy.
280+ | o == 0 = unsafeTake n bs
281+ -- offset. ugg. this is really naive and slow. but also pretty easy :)
282+ | otherwise = B.pack (P.map (readWord8 8) (P.take n (iterate (incS 8) s)))
283+
284+readWithoutOffset :: (Bits a, Num a)
285+ => S -> (a -> Int -> a) -> (a -> Int -> a) -> Int -> a
286+readWithoutOffset (S bs o) shifterL shifterR n
287+ | o /= 0 = error "readWithoutOffset: there is an offset"
288+
289+ | bit_offset n == 0 && byte_offset n <= 4 =
290+ let segs = byte_offset n
291+ bn 0 = fromIntegral (unsafeHead bs)
292+ bn n = (bn (n-1) `shifterL` 8) .|. fromIntegral (unsafeIndex bs n)
293+
294+ in bn (segs-1)
281295
296+ | n <= 64 = let segs = byte_offset n
297+ o' = bit_offset (n - 8 + o)
298+
299+ bn 0 = fromIntegral (unsafeHead bs)
300+ bn n = (bn (n-1) `shifterL` 8) .|. fromIntegral (unsafeIndex bs n)
301+
302+ msegs = bn (segs-1) `shifterL` o'
303+
304+ last = (fromIntegral (unsafeIndex bs segs)) `shifterR` (8 - o')
305+
306+ w = msegs .|. last
307+ in w
308+
309+readWithOffset :: (Bits a, Num a)
310+ => S -> (a -> Int -> a) -> (a -> Int -> a) -> Int -> a
311+readWithOffset (S bs o) shifterL shifterR n
312+ | n <= 64 = let bits_in_msb = 8 - o
313+ (n',top) = (n - bits_in_msb
314+ , (fromIntegral (unsafeHead bs) .&. make_mask bits_in_msb) `shifterL` n')
315+
316+ segs = byte_offset n'
317+
318+ bn 0 = 0
319+ bn n = (bn (n-1) `shifterL` 8) .|. fromIntegral (unsafeIndex bs n)
320+
321+ o' = bit_offset n'
322+
323+ mseg = bn segs `shifterL` o'
324+
325+ last | o' > 0 = (fromIntegral (unsafeIndex bs (segs + 1))) `shifterR` (8 - o')
326+ | otherwise = 0
327+
328+ w = top .|. mseg .|. last
329+ in w
282330
283331------------------------------------------------------------------------
284332-- | 'BitGet' is a monad, applicative and a functor. See 'runBitGet'
@@ -287,6 +335,7 @@ newtype BitGet a = B { runState :: S -> Get (S,a) }
287335
288336instance Monad BitGet where
289337 return x = B $ \s -> return (s,x)
338+ fail str = B $ \_s -> fail str
290339 (B f) >>= g = B $ \s -> do (s',a) <- f s
291340 runState (g a) s'
292341
@@ -297,200 +346,124 @@ instance Applicative BitGet where
297346 pure x = return x
298347 fm <*> m = fm >>= \f -> m >>= \v -> return (f v)
299348
300−instance BitOrderable BitGet where
301− setBitOrder bo = do
302− (S bs o _) <- getState
303− putState (S bs o bo)
304−
305− getBitOrder = do
306− (S _ _ bo) <- getState
307− return bo
308−
309−instance Alignable BitGet where
310− -- | Skip the given number of bits
311− skipBits n = do
312− ensureBits n
313− withState (incS n)
314−
315− -- | Skip bits if necessary to align to the next byte
316− alignByte = do
317− (S _ o _) <- getState
318− when (o /= 0) $
319− skipBits (8-o)
320−
321−
322−
323349-- | Run a 'BitGet' within the Binary packages 'Get' monad. If a byte has
324350-- been partially consumed it will be discarded once 'runBitGet' is finished.
325351runBitGet :: BitGet a -> Get a
326352runBitGet bg = do
327− s <- mkInitState
328− (s',a) <- runState bg s
329− putBackState s'
353+ (_,a) <- runState bg (S B.empty 0)
330354 return a
331355
332−mkInitState :: Get S
333−mkInitState = do
334− bs <- get
335− put B.empty
336− return (S bs 0 BB)
337−
338−putBackState :: S -> Get ()
339−putBackState (S bs o _) = do
340− remaining <- get
341− let bs' = case o of
342− 0 -> bs
343− _ -> unsafeDrop 1 bs
344− put (bs' `B.append` remaining)
345−
346356getState :: BitGet S
347357getState = B $ \s -> return (s,s)
348358
349359putState :: S -> BitGet ()
350360putState s = B $ \_ -> return (s,())
351361
352−withState :: (S -> S) -> BitGet ()
353−withState f = do
354− s <- getState
355− putState $! f s
362+modifyState :: (S -> (S,a)) -> BitGet a
363+modifyState f = B $ \s -> return (f s)
356364
357365-- | Make sure there are at least @n@ bits.
358366ensureBits :: Int -> BitGet ()
359367ensureBits n = do
360− (S bs o bo) <- getState
368+ (S bs o) <- getState
361369 if n <= (B.length bs * 8 - o)
362370 then return ()
363371 else do let currentBits = B.length bs * 8 - o
364− let byteCount = byte_offset (n - currentBits + 7)
365− B $ \_ -> do B.ensureN byteCount
366− bs' <- B.get
367− put B.empty
368− return (S (bs`append`bs') o bo, ())
369−
370−-- | Test whether all input has been consumed, i.e. there are no remaining
371−-- undecoded bytes.
372−isEmpty :: BitGet Bool
373−isEmpty = B $ \ (S bs o bo) -> if B.null bs
374− then B.isEmpty >>= \e -> return (S bs o bo, e)
375− else return (S bs o bo, False)
372+ let byteCount = (n - currentBits + 7) `div` 8
373+ B $ \_ -> do bs' <- B.getByteString byteCount
374+ return (S (bs`append`bs') o, ())
376375
377376-- | Get 1 bit as a 'Bool'.
378377getBool :: BitGet Bool
379378getBool = block bool
380379
381−-- | Get 1 bit as a 'Bool'.
382−getBool# :: BitGet Int
383−getBool# = block bool#
384−
385380-- | Get @n@ bits as a 'Word8'. @n@ must be within @[0..8]@.
386381getWord8 :: Int -> BitGet Word8
387382getWord8 n = block (word8 n)
388383
389384-- | Get @n@ bits as a 'Word16'. @n@ must be within @[0..16]@.
390−getWord16 :: Int -> BitGet Word16
391−getWord16 n = block (word16 n)
392−
393385getWord16be :: Int -> BitGet Word16
394−getWord16be = getWord16
395−{-# DEPRECATED getWord16be "Use 'getWord16' instead" #-}
386+getWord16be n = block (word16be n)
396387
397388-- | Get @n@ bits as a 'Word32'. @n@ must be within @[0..32]@.
398−getWord32 :: Int -> BitGet Word32
399−getWord32 n = block (word32 n)
400−
401389getWord32be :: Int -> BitGet Word32
402−getWord32be = getWord32
403−{-# DEPRECATED getWord32be "Use 'getWord32' instead" #-}
390+getWord32be n = block (word32be n)
404391
405392-- | Get @n@ bits as a 'Word64'. @n@ must be within @[0..64]@.
406−getWord64 :: Int -> BitGet Word64
407−getWord64 n = block (word64 n)
408−
409393getWord64be :: Int -> BitGet Word64
410−getWord64be = getWord64
411−{-# DEPRECATED getWord64be "Use 'getWord64' instead" #-}
394+getWord64be n = block (word64be n)
412395
413396-- | Get @n@ bytes as a 'ByteString'.
414397getByteString :: Int -> BitGet ByteString
415398getByteString n = block (byteString n)
416399
417−-- | Get @n@ bytes as a lazy ByteString.
418−getLazyByteString :: Int -> BitGet L.ByteString
419−getLazyByteString n = do
420− (S _ o bo) <- getState
421− case o of
422− 0 -> B $ \s -> do
423− putBackState s
424− lbs <- B.getLazyByteString (fromIntegral n)
425− return (S B.empty 0 bo, lbs)
426− _ -> L.fromChunks . (:[]) <$> Data.Binary.Bits.Get.getByteString n
427−
428−
429−
430−
431−
432−-- | A block that will be read with only one boundary check. Needs to know the
433−-- number of bits in advance.
434−data Block a = Block Int (S -> a)
435−
436−instance Functor Block where
437− fmap f (Block i p) = Block i (\s -> f (p s))
438−
439−instance Applicative Block where
440− pure a = Block 0 (\_ -> a)
441− (Block i p) <*> (Block j q) = Block (i+j) (\s -> p s $ q (incS i s))
442− (Block i _) *> (Block j q) = Block (i+j) (q . incS i)
443− (Block i p) <* (Block j _) = Block (i+j) p
444−
445−-- | Get a block. Will be read with one single boundry check, and
446−-- therefore requires a statically known number of bits.
447−-- Build blocks using 'bool', 'word8', 'word16be', 'word32be', 'word64be',
448−-- 'byteString' and 'Applicative'.
449−block :: Block a -> BitGet a
450−block (Block i p) = do
451− ensureBits i
452− s <- getState
453− putState $! (incS i s)
454− return $! p s
455−
456400-- | Read a 1 bit 'Bool'.
457401bool :: Block Bool
458402bool = Block 1 readBool
459403
460−-- | Read a 1 bit 'Bool'.
461−bool# :: Block Int
462−bool# = Block 1 readBool#
463−
464404-- | Read @n@ bits as a 'Word8'. @n@ must be within @[0..8]@.
465405word8 :: Int -> Block Word8
466−word8 n = Block n (readWordChecked 8 n)
406+word8 n = Block n (readWord8 n)
467407
468408-- | Read @n@ bits as a 'Word16'. @n@ must be within @[0..16]@.
469−word16 :: Int -> Block Word16
470−word16 n = Block n (readWordChecked 16 n)
471−
472409word16be :: Int -> Block Word16
473−word16be = word16
474−{-# DEPRECATED word16be "Use 'word16' instead" #-}
410+word16be n = Block n (readWord16be n)
475411
476412-- | Read @n@ bits as a 'Word32'. @n@ must be within @[0..32]@.
477−word32 :: Int -> Block Word32
478−word32 n = Block n (readWordChecked 32 n)
479−
480413word32be :: Int -> Block Word32
481−word32be = word32
482−{-# DEPRECATED word32be "Use 'word32' instead" #-}
414+word32be n = Block n (readWord32be n)
483415
484416-- | Read @n@ bits as a 'Word64'. @n@ must be within @[0..64]@.
485−word64 :: Int -> Block Word64
486−word64 n = Block n (readWordChecked 64 n)
487−
488417word64be :: Int -> Block Word64
489−word64be = word64
490−{-# DEPRECATED word64be "Use 'word64' instead" #-}
418+word64be n = Block n (readWord64be n)
491419
492420-- | Read @n@ bytes as a 'ByteString'.
493421byteString :: Int -> Block ByteString
494422byteString n | n > 0 = Block (n*8) (readByteString n)
495423 | otherwise = Block 0 (\_ -> B.empty)
496424
425+------------------------------------------------------------------------
426+-- Unchecked shifts, from the package binary
427+
428+shiftl_w16 :: Word16 -> Int -> Word16
429+shiftl_w32 :: Word32 -> Int -> Word32
430+shiftl_w64 :: Word64 -> Int -> Word64
431+
432+#if defined(__GLASGOW_HASKELL__) && !defined(__HADDOCK__)
433+shiftl_w8 (W8# w) (I# i) = W8# (w `uncheckedShiftL#` i)
434+shiftl_w16 (W16# w) (I# i) = W16# (w `uncheckedShiftL#` i)
435+shiftl_w32 (W32# w) (I# i) = W32# (w `uncheckedShiftL#` i)
436+
437+shiftr_w8 (W8# w) (I# i) = W8# (w `uncheckedShiftRL#` i)
438+shiftr_w16 (W16# w) (I# i) = W16# (w `uncheckedShiftRL#` i)
439+shiftr_w32 (W32# w) (I# i) = W32# (w `uncheckedShiftRL#` i)
440+
441+
442+#if WORD_SIZE_IN_BITS < 64
443+shiftl_w64 (W64# w) (I# i) = W64# (w `uncheckedShiftL64#` i)
444+shiftr_w64 (W64# w) (I# i) = W64# (w `uncheckedShiftRL64#` i)
445+
446+#if __GLASGOW_HASKELL__ <= 606
447+-- Exported by GHC.Word in GHC 6.8 and higher
448+foreign import ccall unsafe "stg_uncheckedShiftL64"
449+ uncheckedShiftL64# :: Word64# -> Int# -> Word64#
450+foreign import ccall unsafe "stg_uncheckedShiftRL64"
451+ uncheckedShiftRL64# :: Word64# -> Int# -> Word64#
452+#endif
453+
454+#else
455+shiftl_w64 (W64# w) (I# i) = W64# (w `uncheckedShiftL#` i)
456+shiftr_w64 (W64# w) (I# i) = W64# (w `uncheckedShiftRL#` i)
457+#endif
458+
459+#else
460+shiftl_w8 = shiftL
461+shiftl_w16 = shiftL
462+shiftl_w32 = shiftL
463+shiftl_w64 = shiftL
464+
465+shiftr_w8 = shiftR
466+shiftr_w16 = shiftR
467+shiftr_w32 = shiftR
468+shiftr_w64 = shiftR
469+#endif