mkFastSubStringBA#, -- :: ByteArray# -> Int# -> Int# -> FastString
mkFastSubString#, -- :: Addr# -> Int# -> Int# -> FastString
mkFastSubStringFO#, -- :: ForeignObj# -> Int# -> Int# -> FastString
-
+
+ mkFastStringInt, -- :: [Int] -> FastString
+
uniqueOfFS, -- :: FastString -> Int#
lengthFS, -- :: FastString -> Int
nullFastString, -- :: FastString -> Bool
- getByteArray#, -- :: FastString -> ByteArray#
- getByteArray, -- :: FastString -> _ByteArray Int
unpackFS, -- :: FastString -> String
+ unpackIntFS, -- :: FastString -> [Int]
appendFS, -- :: FastString -> FastString -> FastString
headFS, -- :: FastString -> Char
+ headIntFS, -- :: FastString -> Int
tailFS, -- :: FastString -> FastString
concatFS, -- :: [FastString] -> FastString
consFS, -- :: Char -> FastString -> FastString
import IOExts ( IORef, newIORef, readIORef, writeIORef )
import IO
+import Char ( chr, ord )
#define hASH_TBL_SIZE 993
Addr# -- pointer to the (null-terminated) bytes in C land.
Int# -- length (cached)
+ | UnicodeStr -- if contains characters outside '\1'..'\xFF'
+ Int# -- unique id
+ [Int] -- character numbers
+
instance Eq FastString where
a == b = case cmpFS a b of { LT -> False; EQ -> True; GT -> False }
a /= b = case cmpFS a b of { LT -> True; EQ -> False; GT -> True }
| otherwise = y
compare a b = cmpFS a b
-getByteArray# :: FastString -> ByteArray#
-getByteArray# (FastString _ _ ba#) = ba#
-
-getByteArray :: FastString -> ByteArray Int
-#if __GLASGOW_HASKELL__ < 405
-getByteArray (FastString _ l# ba#) = ByteArray (0,I# l#) ba#
-#else
-getByteArray (FastString _ l# ba#) = ByteArray 0 (I# l#) ba#
-#endif
-
lengthFS :: FastString -> Int
lengthFS (FastString _ l# _) = I# l#
lengthFS (CharStr a# l#) = I# l#
+lengthFS (UnicodeStr _ s) = length s
nullFastString :: FastString -> Bool
nullFastString (FastString _ l# _) = l# ==# 0#
nullFastString (CharStr _ l#) = l# ==# 0#
+nullFastString (UnicodeStr _ []) = True
+nullFastString (UnicodeStr _ (_:_)) = False
unpackFS :: FastString -> String
unpackFS (FastString _ l# ba#) = unpackNBytesBA# ba# l#
| otherwise = C# ch : unpack (nh +# 1#)
where
ch = indexCharOffAddr# addr nh
+unpackFS (UnicodeStr _ s) = map chr s
+
+unpackIntFS :: FastString -> [Int]
+unpackIntFS (UnicodeStr _ s) = s
+unpackIntFS fs = map ord (unpackFS fs)
appendFS :: FastString -> FastString -> FastString
-appendFS fs1 fs2 = mkFastString (unpackFS fs1 ++ unpackFS fs2)
+appendFS fs1 fs2 = mkFastStringInt (unpackIntFS fs1 ++ unpackIntFS fs2)
concatFS :: [FastString] -> FastString
-concatFS ls = mkFastString (concat (map (unpackFS) ls)) -- ToDo: do better
+concatFS ls = mkFastStringInt (concat (map unpackIntFS ls)) -- ToDo: do better
headFS :: FastString -> Char
-headFS f@(FastString _ l# ba#) =
- if l# ># 0# then C# (indexCharArray# ba# 0#) else error ("headFS: empty FS: " ++ unpackFS f)
-headFS f@(CharStr a# l#) =
- if l# ># 0# then C# (indexCharOffAddr# a# 0#) else error ("headFS: empty FS: " ++ unpackFS f)
+headFS (FastString _ l# ba#) =
+ if l# ># 0# then C# (indexCharArray# ba# 0#) else error ("headFS: empty FS")
+headFS (CharStr a# l#) =
+ if l# ># 0# then C# (indexCharOffAddr# a# 0#) else error ("headFS: empty FS")
+headFS (UnicodeStr _ (c:_)) = chr c
+headFS (UnicodeStr _ []) = error ("headFS: empty FS")
+
+headIntFS :: FastString -> Int
+headIntFS (UnicodeStr _ (c:_)) = c
+headIntFS fs = ord (headFS fs)
indexFS :: FastString -> Int -> Char
indexFS f i@(I# i#) =
CharStr a# l#
| l# ># 0# && l# ># i# -> C# (indexCharOffAddr# a# i#)
| otherwise -> error (msg (I# l#))
+ UnicodeStr _ s -> chr (s!!i)
where
msg l = "indexFS: out of range: " ++ show (l,i)
tailFS :: FastString -> FastString
tailFS (FastString _ l# ba#) = mkFastSubStringBA# ba# 1# (l# -# 1#)
+tailFS fs = mkFastStringInt (tail (unpackIntFS fs))
consFS :: Char -> FastString -> FastString
-consFS c fs = mkFastString (c:unpackFS fs)
+consFS c fs = mkFastStringInt (ord c : unpackIntFS fs)
uniqueOfFS :: FastString -> Int#
uniqueOfFS (FastString u# _ _) = u#
works, but causes the CharStr to be looked up in the hash
table each time it is accessed..
-}
+uniqueOfFS (UnicodeStr u# _) = u#
\end{code}
Internally, the compiler will maintain a fast string symbol
new @FastString@s then covertly does a lookup, re-using the
@FastString@ if there was a hit.
+Caution: mkFastStringUnicode assumes that if the string is in the
+table, it sits under the UnicodeStr constructor. Other mkFastString
+variants analogously assume the FastString constructor.
+
\begin{code}
data FastStringTable =
FastStringTable
Just v
else
bucket_match ls len# a#
+ bucket_match (UnicodeStr _ _ : ls) len# a# =
+ bucket_match ls len# a#
mkFastSubString# :: Addr# -> Int# -> Int# -> FastString
mkFastSubString# a# start# len# = mkFastCharString2 (A# (addrOffset# a# start#)) (I# len#)
Just v
else
bucket_match ls start# len# fo#
-
+ bucket_match (UnicodeStr _ _ : ls) start# len# fo# =
+ bucket_match ls start# len# fo#
mkFastSubStringBA# :: ByteArray# -> Int# -> Int# -> FastString
mkFastSubStringBA# barr# start# len# =
Just v
else
bucket_match ls start# len# ba#
+ UnicodeStr _ _ -> bucket_match ls start# len# ba#
+
+mkFastStringUnicode :: [Int] -> FastString
+mkFastStringUnicode s =
+ unsafePerformIO (
+ readIORef string_table >>= \ ft@(FastStringTable uid# tbl#) ->
+ let
+ h = hashUnicode s
+ in
+-- _trace ("hashed(b): "++show (I# h)) $
+ lookupTbl ft h >>= \ lookup_result ->
+ case lookup_result of
+ [] ->
+ -- no match, add it to table by copying out the
+ -- the string into a [Int]
+ let f_str = UnicodeStr uid# s in
+ updTbl string_table ft h [f_str] >>
+ -- _trace ("new(b): " ++ show f_str) $
+ return f_str
+ ls ->
+ -- non-empty `bucket', scan the list looking
+ -- entry with same length and compare byte by byte.
+ -- _trace ("non-empty bucket(b)"++show ls) $
+ case bucket_match ls of
+ Nothing ->
+ let f_str = UnicodeStr uid# s in
+ updTbl string_table ft h (f_str:ls) >>
+ -- _trace ("new(b): " ++ show f_str) $
+ return f_str
+ Just v ->
+ -- _trace ("re-use(b): "++show v) $
+ return v
+ )
+ where
+ bucket_match [] = Nothing
+ bucket_match (v@(UnicodeStr _ s'):ls) =
+ if s' == s then Just v else bucket_match ls
+ bucket_match (FastString _ _ _ : ls) = bucket_match ls
mkFastCharString :: Addr -> FastString
mkFastCharString a@(A# a#) =
mkFastCharString2 :: Addr -> Int -> FastString
mkFastCharString2 a@(A# a#) (I# len#) = CharStr a# len#
-mkFastString :: String -> FastString
-mkFastString str =
+mkFastStringNarrow :: String -> FastString
+mkFastStringNarrow str =
case packString str of
#if __GLASGOW_HASKELL__ < 405
(ByteArray (_,I# len#) frozen#) ->
{- 0-indexed array, len# == index to one beyond end of string,
i.e., (0,1) => empty string. -}
+mkFastString :: String -> FastString
+mkFastString str = if all good str
+ then mkFastStringNarrow str
+ else mkFastStringUnicode (map ord str)
+ where
+ good c = c >= '\1' && c <= '\xFF'
+
+mkFastStringInt :: [Int] -> FastString
+mkFastStringInt str = if all good str
+ then mkFastStringNarrow (map chr str)
+ else mkFastStringUnicode str
+ where
+ good c = c >= 1 && c <= 0xFF
+
mkFastSubString :: Addr -> Int -> Int -> FastString
mkFastSubString (A# a#) (I# start#) (I# len#) =
mkFastString# (addrOffset# a# start#) len#
-- c1 = indexCharArray# ba# 1#
-- c2 = indexCharArray# ba# 2#
+hashUnicode :: [Int] -> Int#
+ -- use the Addr to produce a hash value between 0 & m (inclusive)
+hashUnicode [] = 0#
+hashUnicode [I# c0] = ((c0 *# 631#) +# 1#) `remInt#` hASH_TBL_SIZE#
+hashUnicode [I# c0, I# c1] = ((c0 *# 631#) +# (c1 *# 217#) +# 2#) `remInt#` hASH_TBL_SIZE#
+hashUnicode s = ((c0 *# 631#) +# (c1 *# 217#) +# (c2 *# 43#) +# len#) `remInt#` hASH_TBL_SIZE#
+ where
+ I# len# = length s
+ I# c0 = s !! 0
+ I# c1 = s !! (I# (len# `quotInt#` 2# -# 1#))
+ I# c2 = s !! (I# (len# -# 1#))
+
\end{code}
\begin{code}
cmpFS :: FastString -> FastString -> Ordering
+cmpFS (UnicodeStr u1# s1) (UnicodeStr u2# s2) = if u1# ==# u2# then EQ
+ else compare s1 s2
+cmpFS (UnicodeStr _ s1) s2 = compare s1 (unpackIntFS s2)
+cmpFS s1 (UnicodeStr _ s2) = compare (unpackIntFS s1) s2
cmpFS (FastString u1# _ b1#) (FastString u2# _ b2#) = -- assume non-null chars
if u1# ==# u2# then
EQ
projects / ghc-hetmet.git / blobdiff