on master help sign in
Data/Binary/Bits/Internal.hs+21
since splitsnapshots
unifiedsplit
@@ -12,10 +12,13 @@
12
12
13module Data.Binary.Bits.Internal
13module Data.Binary.Bits.Internal
14 ( make_mask
14 ( make_mask
15+ , make_mask#
15 , mask
16 , mask
17+ , mask#
16 , bit_offset
18 , bit_offset
17 , byte_offset
19 , byte_offset
18 , reverseBits
20 , reverseBits
21+ , reverseBits#
19 , FastBits(..)
22 , FastBits(..)
20 )
23 )
21where
24where
@@ -38,11 +41,18 @@ make_mask n = (1 `shiftL` fromIntegral n) - 1
38{-# SPECIALIZE make_mask :: Int -> Word32 #-}
41{-# SPECIALIZE make_mask :: Int -> Word32 #-}
39{-# SPECIALIZE make_mask :: Int -> Word64 #-}
42{-# SPECIALIZE make_mask :: Int -> Word64 #-}
40
43
44+make_mask# :: Int# -> Word#
45+make_mask# n = (1## `shiftL#` n) `minusWord#` 1##
46+
41-- | Keep only the n least-significant bits of the given value
47-- | Keep only the n least-significant bits of the given value
42mask :: (Bits a, Num a) => Int -> a -> a
48mask :: (Bits a, Num a) => Int -> a -> a
43mask n v = v .&. make_mask n
49mask n v = v .&. make_mask n
44{-# INLINE mask #-}
50{-# INLINE mask #-}
45
51
52+-- | Keep only the n least-significant bits of the given value
53+mask# :: Int# -> Word# -> Word#
54+mask# n v = v `and#` make_mask# n
55+
46-- | Compute bit offset (equivalent to x `mod` 8 but faster)
56-- | Compute bit offset (equivalent to x `mod` 8 but faster)
47bit_offset :: Int -> Int
57bit_offset :: Int -> Int
48bit_offset n = make_mask 3 .&. n
58bit_offset n = make_mask 3 .&. n
@@ -65,6 +75,17 @@ reverseBits n value = rec value n 0
65 rec 0 i r = r `fastShiftL` i
75 rec 0 i r = r `fastShiftL` i
66 rec v i r = rec (v `fastShiftR` 1) (i-1) ((r `fastShiftL` 1) .|. (v .&. 0x1))
76 rec v i r = rec (v `fastShiftR` 1) (i-1) ((r `fastShiftL` 1) .|. (v .&. 0x1))
67
77
78+reverseBits# :: Int# -> Word# -> Word#
79+reverseBits# n value = rec value n 0##
80+ where
81+ -- rec v i r, where
82+ -- v is orginal value shifted
83+ -- i is the remaining number of bits
84+ -- r is current value
85+ rec 0## 0# r = r
86+ rec 0## i r = r `shiftL#` i
87+ rec v i r = rec (v `shiftRL#` 1#) (i -# 1#) ((r `shiftL#` 1#) `or#` (v `and#` 0x1##))
88+
68
89
69---------------------------------------------------------------------
90---------------------------------------------------------------------
70-- Unchecked shifts, from the "binary" package
91-- Unchecked shifts, from the "binary" package
Data/Binary/Bits/Put.hs+60−2
@@ -1,3 +1,5 @@
1+{-# LANGUAGE MagicHash #-}
2+
1-----------------------------------------------------------------------------
3-----------------------------------------------------------------------------
2-- |
4-- |
3-- Module : Data.Binary.Bits.Put
5-- Module : Data.Binary.Bits.Put
@@ -20,8 +22,10 @@ module Data.Binary.Bits.Put
20 -- * Data types
22 -- * Data types
21 -- ** Bool
23 -- ** Bool
22 , putBool
24 , putBool
25+ , putBool#
23
26
24 -- ** Words
27 -- ** Words
28+ , putWord#
25 , putWord8
29 , putWord8
26 , putWord16
30 , putWord16
27 , putWord32
31 , putWord32
@@ -46,11 +50,11 @@ import Data.Binary.Bits.Alignment
46import Data.ByteString as BS
50import Data.ByteString as BS
47import Data.ByteString.Unsafe as BS
51import Data.ByteString.Unsafe as BS
48
52
49−import Control.Applicative
50import Control.Monad (when)
53import Control.Monad (when)
51import Data.Bits
54import Data.Bits
52−import Data.Monoid
53import Data.Word
55import Data.Word
56+import GHC.Base (Word#, shiftRL#, Int (..), Int#, (-#), (<#), isTrue#, (+#), shiftL#, wordToWord8#, orWord8#)
57+import GHC.Word (Word8(..))
54
58
55data BitPut a = BitPut { run :: (S -> PairS a) }
59data BitPut a = BitPut { run :: (S -> PairS a) }
56
60
@@ -62,11 +66,18 @@ data S = S !Builder !Word8 !Int !BitOrder
62putBool :: Bool -> BitPut ()
66putBool :: Bool -> BitPut ()
63putBool b = putWord8 1 (if b then 0xff else 0x00)
67putBool b = putWord8 1 (if b then 0xff else 0x00)
64
68
69+-- | Put a 1 bit 'Bool'.
70+putBool# :: Word# -> BitPut ()
71+putBool# b = putWord# 1# b
72+
65
73
66-- | Generic putWord
74-- | Generic putWord
67putWord :: (Num a, FastBits a, Integral a) => Int -> a -> BitPut ()
75putWord :: (Num a, FastBits a, Integral a) => Int -> a -> BitPut ()
68putWord n w = BitPut $ \s -> PairS () (putWordS n w s)
76putWord n w = BitPut $ \s -> PairS () (putWordS n w s)
69
77
78+putWord# :: Int# -> Word# -> BitPut ()
79+putWord# n w = BitPut $ \s -> PairS () (putWordS# n w s)
80+
70putWordS :: (Num a, FastBits a, Integral a) => Int -> a -> S -> S
81putWordS :: (Num a, FastBits a, Integral a) => Int -> a -> S -> S
71putWordS n w s@(S builder b o bo) = s'
82putWordS n w s@(S builder b o bo) = s'
72 where
83 where
@@ -110,6 +121,53 @@ putWordS n w s@(S builder b o bo) = s'
110 | o2 == 8 = S (b2 `mappend` B.singleton w2) 0 0 bo2
121 | o2 == 8 = S (b2 `mappend` B.singleton w2) 0 0 bo2
111 | otherwise = s2
122 | otherwise = s2
112
123
124+putWordS# :: Int# -> Word# -> S -> S
125+putWordS# n w s@(S builder (W8# b) (I# o) bo) = s'
126+ where
127+ min# :: Int# -> Int# -> Int#
128+ min# x y | isTrue# (x <# y) = x
129+ min# _ y = y
130+
131+ -- number of bits that will be stored in the current byte
132+ cn = min# (8# -# o) n
133+
134+ -- new state
135+ s' = case n of
136+ 0# -> s
137+ _ -> putWordS# (n -# cn) w' (flush (S builder (W8# b') (I# (o +# cn)) bo))
138+
139+ -- new current byte
140+ b' = wordToWord8# (shl (selectBits w)) `orWord8#` b
141+
142+ -- Word containing the remaining (n-cn) bits to store in its LSB
143+ w' = case bo of
144+ BB -> w
145+ BL -> w `shiftRL#` cn
146+ LL -> w `shiftRL#` cn
147+ LB -> w
148+
149+ -- Select bits to store in the current byte.
150+ -- Put them in the correct order and return them in the least-significant
151+ -- bits of the returned value
152+ selectBits :: Word# -> Word#
153+ selectBits x = case bo of
154+ BB -> mask# cn (x `shiftRL#` (n -# cn))
155+ LB -> reverseBits# cn (mask# cn (x `shiftRL#` (n -# cn)))
156+ LL -> mask# cn x
157+ BL -> reverseBits# cn (mask# cn x)
158+
159+ -- shift left at the correct position
160+ shl :: Word# -> Word#
161+ shl x = case bo of
162+ BB -> x `shiftL#` (8# -# o -# cn)
163+ BL -> x `shiftL#` (8# -# o -# cn)
164+ LL -> x `shiftL#` o
165+ LB -> x `shiftL#` o
166+
167+ flush s2@(S b2 w2 o2 bo2)
168+ | o2 == 8 = S (b2 `mappend` B.singleton w2) 0 0 bo2
169+ | otherwise = s2
170+
113
171
114-- | Put the @n@ lower bits of a 'Word8'.
172-- | Put the @n@ lower bits of a 'Word8'.
115putWord8 :: Int -> Word8 -> BitPut ()
173putWord8 :: Int -> Word8 -> BitPut ()