X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Futils%2FEncoding.hs;fp=ghc%2Fcompiler%2Futils%2FEncoding.hs;h=0000000000000000000000000000000000000000;hb=0065d5ab628975892cea1ec7303f968c3338cbe1;hp=152bf3c60eb0d56ba74dce577c28e33ed6e6db20;hpb=28a464a75e14cece5db40f2765a29348273ff2d2;p=ghc-hetmet.git diff --git a/ghc/compiler/utils/Encoding.hs b/ghc/compiler/utils/Encoding.hs deleted file mode 100644 index 152bf3c..0000000 --- a/ghc/compiler/utils/Encoding.hs +++ /dev/null @@ -1,373 +0,0 @@ --- ----------------------------------------------------------------------------- --- --- (c) The University of Glasgow, 1997-2006 --- --- Character encodings --- --- ----------------------------------------------------------------------------- - -module Encoding ( - -- * UTF-8 - utf8DecodeChar#, - utf8PrevChar, - utf8CharStart, - utf8DecodeChar, - utf8DecodeString, - utf8EncodeChar, - utf8EncodeString, - utf8EncodedLength, - countUTF8Chars, - - -- * Z-encoding - zEncodeString, - zDecodeString - ) where - -#define COMPILING_FAST_STRING -#include "HsVersions.h" -import Foreign -import Data.Char ( ord, chr, isDigit, digitToInt, isHexDigit ) -import Numeric ( showHex ) - -import Data.Bits -import GHC.Ptr ( Ptr(..) ) -import GHC.Base - --- ----------------------------------------------------------------------------- --- UTF-8 - --- We can't write the decoder as efficiently as we'd like without --- resorting to unboxed extensions, unfortunately. I tried to write --- an IO version of this function, but GHC can't eliminate boxed --- results from an IO-returning function. --- --- We assume we can ignore overflow when parsing a multibyte character here. --- To make this safe, we add extra sentinel bytes to unparsed UTF-8 sequences --- before decoding them (see StringBuffer.hs). - -{-# INLINE utf8DecodeChar# #-} -utf8DecodeChar# :: Addr# -> (# Char#, Addr# #) -utf8DecodeChar# a# = - let ch0 = word2Int# (indexWord8OffAddr# a# 0#) in - case () of - _ | ch0 <=# 0x7F# -> (# chr# ch0, a# `plusAddr#` 1# #) - - | ch0 >=# 0xC0# && ch0 <=# 0xDF# -> - let ch1 = word2Int# (indexWord8OffAddr# a# 1#) in - if ch1 <# 0x80# || ch1 >=# 0xC0# then fail 1# else - (# chr# (((ch0 -# 0xC0#) `uncheckedIShiftL#` 6#) +# - (ch1 -# 0x80#)), - a# `plusAddr#` 2# #) - - | ch0 >=# 0xE0# && ch0 <=# 0xEF# -> - let ch1 = word2Int# (indexWord8OffAddr# a# 1#) in - if ch1 <# 0x80# || ch1 >=# 0xC0# then fail 1# else - let ch2 = word2Int# (indexWord8OffAddr# a# 2#) in - if ch2 <# 0x80# || ch2 >=# 0xC0# then fail 2# else - (# chr# (((ch0 -# 0xE0#) `uncheckedIShiftL#` 12#) +# - ((ch1 -# 0x80#) `uncheckedIShiftL#` 6#) +# - (ch2 -# 0x80#)), - a# `plusAddr#` 3# #) - - | ch0 >=# 0xF0# && ch0 <=# 0xF8# -> - let ch1 = word2Int# (indexWord8OffAddr# a# 1#) in - if ch1 <# 0x80# || ch1 >=# 0xC0# then fail 1# else - let ch2 = word2Int# (indexWord8OffAddr# a# 2#) in - if ch2 <# 0x80# || ch2 >=# 0xC0# then fail 2# else - let ch3 = word2Int# (indexWord8OffAddr# a# 3#) in - if ch3 <# 0x80# || ch3 >=# 0xC0# then fail 3# else - (# chr# (((ch0 -# 0xF0#) `uncheckedIShiftL#` 18#) +# - ((ch1 -# 0x80#) `uncheckedIShiftL#` 12#) +# - ((ch2 -# 0x80#) `uncheckedIShiftL#` 6#) +# - (ch3 -# 0x80#)), - a# `plusAddr#` 4# #) - - | otherwise -> fail 1# - where - -- all invalid sequences end up here: - fail n = (# '\0'#, a# `plusAddr#` n #) - -- '\xFFFD' would be the usual replacement character, but - -- that's a valid symbol in Haskell, so will result in a - -- confusing parse error later on. Instead we use '\0' which - -- will signal a lexer error immediately. - -utf8DecodeChar :: Ptr Word8 -> (Char, Ptr Word8) -utf8DecodeChar (Ptr a#) = - case utf8DecodeChar# a# of (# c#, b# #) -> ( C# c#, Ptr b# ) - --- UTF-8 is cleverly designed so that we can always figure out where --- the start of the current character is, given any position in a --- stream. This function finds the start of the previous character, --- assuming there *is* a previous character. -utf8PrevChar :: Ptr Word8 -> IO (Ptr Word8) -utf8PrevChar p = utf8CharStart (p `plusPtr` (-1)) - -utf8CharStart :: Ptr Word8 -> IO (Ptr Word8) -utf8CharStart p = go p - where go p = do w <- peek p - if w >= 0x80 && w < 0xC0 - then go (p `plusPtr` (-1)) - else return p - -utf8DecodeString :: Ptr Word8 -> Int -> IO [Char] -STRICT2(utf8DecodeString) -utf8DecodeString (Ptr a#) (I# len#) - = unpack a# - where - end# = addr2Int# (a# `plusAddr#` len#) - - unpack p# - | addr2Int# p# >=# end# = return [] - | otherwise = - case utf8DecodeChar# p# of - (# c#, q# #) -> do - chs <- unpack q# - return (C# c# : chs) - -countUTF8Chars :: Ptr Word8 -> Int -> IO Int -countUTF8Chars ptr bytes = go ptr 0 - where - end = ptr `plusPtr` bytes - - STRICT2(go) - go ptr n - | ptr >= end = return n - | otherwise = do - case utf8DecodeChar# (unPtr ptr) of - (# c, a #) -> go (Ptr a) (n+1) - -unPtr (Ptr a) = a - -utf8EncodeChar c ptr = - let x = ord c in - case () of - _ | x > 0 && x <= 0x007f -> do - poke ptr (fromIntegral x) - return (ptr `plusPtr` 1) - -- NB. '\0' is encoded as '\xC0\x80', not '\0'. This is so that we - -- can have 0-terminated UTF-8 strings (see GHC.Base.unpackCStringUtf8). - | x <= 0x07ff -> do - poke ptr (fromIntegral (0xC0 .|. ((x `shiftR` 6) .&. 0x1F))) - pokeElemOff ptr 1 (fromIntegral (0x80 .|. (x .&. 0x3F))) - return (ptr `plusPtr` 2) - | x <= 0xffff -> do - poke ptr (fromIntegral (0xE0 .|. (x `shiftR` 12) .&. 0x0F)) - pokeElemOff ptr 1 (fromIntegral (0x80 .|. (x `shiftR` 6) .&. 0x3F)) - pokeElemOff ptr 2 (fromIntegral (0x80 .|. (x .&. 0x3F))) - return (ptr `plusPtr` 3) - | otherwise -> do - poke ptr (fromIntegral (0xF0 .|. (x `shiftR` 18))) - pokeElemOff ptr 1 (fromIntegral (0x80 .|. ((x `shiftR` 12) .&. 0x3F))) - pokeElemOff ptr 2 (fromIntegral (0x80 .|. ((x `shiftR` 6) .&. 0x3F))) - pokeElemOff ptr 3 (fromIntegral (0x80 .|. (x .&. 0x3F))) - return (ptr `plusPtr` 4) - -utf8EncodeString :: Ptr Word8 -> String -> IO () -utf8EncodeString ptr str = go ptr str - where STRICT2(go) - go ptr [] = return () - go ptr (c:cs) = do - ptr' <- utf8EncodeChar c ptr - go ptr' cs - -utf8EncodedLength :: String -> Int -utf8EncodedLength str = go 0 str - where STRICT2(go) - go n [] = n - go n (c:cs) - | ord c > 0 && ord c <= 0x007f = go (n+1) cs - | ord c <= 0x07ff = go (n+2) cs - | ord c <= 0xffff = go (n+3) cs - | otherwise = go (n+4) cs - --- ----------------------------------------------------------------------------- --- The Z-encoding - -{- -This is the main name-encoding and decoding function. It encodes any -string into a string that is acceptable as a C name. This is done -right before we emit a symbol name into the compiled C or asm code. -Z-encoding of strings is cached in the FastString interface, so we -never encode the same string more than once. - -The basic encoding scheme is this. - -* Tuples (,,,) are coded as Z3T - -* Alphabetic characters (upper and lower) and digits - all translate to themselves; - except 'Z', which translates to 'ZZ' - and 'z', which translates to 'zz' - We need both so that we can preserve the variable/tycon distinction - -* Most other printable characters translate to 'zx' or 'Zx' for some - alphabetic character x - -* The others translate as 'znnnU' where 'nnn' is the decimal number - of the character - - Before After - -------------------------- - Trak Trak - foo_wib foozuwib - > zg - >1 zg1 - foo# foozh - foo## foozhzh - foo##1 foozhzh1 - fooZ fooZZ - :+ ZCzp - () Z0T 0-tuple - (,,,,) Z5T 5-tuple - (# #) Z1H unboxed 1-tuple (note the space) - (#,,,,#) Z5H unboxed 5-tuple - (NB: There is no Z1T nor Z0H.) --} - -type UserString = String -- As the user typed it -type EncodedString = String -- Encoded form - - -zEncodeString :: UserString -> EncodedString -zEncodeString cs = case maybe_tuple cs of - Just n -> n -- Tuples go to Z2T etc - Nothing -> go cs - where - go [] = [] - go (c:cs) = encode_ch c ++ go cs - -unencodedChar :: Char -> Bool -- True for chars that don't need encoding -unencodedChar 'Z' = False -unencodedChar 'z' = False -unencodedChar c = c >= 'a' && c <= 'z' - || c >= 'A' && c <= 'Z' - || c >= '0' && c <= '9' - -encode_ch :: Char -> EncodedString -encode_ch c | unencodedChar c = [c] -- Common case first - --- Constructors -encode_ch '(' = "ZL" -- Needed for things like (,), and (->) -encode_ch ')' = "ZR" -- For symmetry with ( -encode_ch '[' = "ZM" -encode_ch ']' = "ZN" -encode_ch ':' = "ZC" -encode_ch 'Z' = "ZZ" - --- Variables -encode_ch 'z' = "zz" -encode_ch '&' = "za" -encode_ch '|' = "zb" -encode_ch '^' = "zc" -encode_ch '$' = "zd" -encode_ch '=' = "ze" -encode_ch '>' = "zg" -encode_ch '#' = "zh" -encode_ch '.' = "zi" -encode_ch '<' = "zl" -encode_ch '-' = "zm" -encode_ch '!' = "zn" -encode_ch '+' = "zp" -encode_ch '\'' = "zq" -encode_ch '\\' = "zr" -encode_ch '/' = "zs" -encode_ch '*' = "zt" -encode_ch '_' = "zu" -encode_ch '%' = "zv" -encode_ch c = 'z' : if isDigit (head hex_str) then hex_str - else '0':hex_str - where hex_str = showHex (ord c) "U" - -- ToDo: we could improve the encoding here in various ways. - -- eg. strings of unicode characters come out as 'z1234Uz5678U', we - -- could remove the 'U' in the middle (the 'z' works as a separator). - -zDecodeString :: EncodedString -> UserString -zDecodeString [] = [] -zDecodeString ('Z' : d : rest) - | isDigit d = decode_tuple d rest - | otherwise = decode_upper d : zDecodeString rest -zDecodeString ('z' : d : rest) - | isDigit d = decode_num_esc d rest - | otherwise = decode_lower d : zDecodeString rest -zDecodeString (c : rest) = c : zDecodeString rest - -decode_upper, decode_lower :: Char -> Char - -decode_upper 'L' = '(' -decode_upper 'R' = ')' -decode_upper 'M' = '[' -decode_upper 'N' = ']' -decode_upper 'C' = ':' -decode_upper 'Z' = 'Z' -decode_upper ch = {-pprTrace "decode_upper" (char ch)-} ch - -decode_lower 'z' = 'z' -decode_lower 'a' = '&' -decode_lower 'b' = '|' -decode_lower 'c' = '^' -decode_lower 'd' = '$' -decode_lower 'e' = '=' -decode_lower 'g' = '>' -decode_lower 'h' = '#' -decode_lower 'i' = '.' -decode_lower 'l' = '<' -decode_lower 'm' = '-' -decode_lower 'n' = '!' -decode_lower 'p' = '+' -decode_lower 'q' = '\'' -decode_lower 'r' = '\\' -decode_lower 's' = '/' -decode_lower 't' = '*' -decode_lower 'u' = '_' -decode_lower 'v' = '%' -decode_lower ch = {-pprTrace "decode_lower" (char ch)-} ch - --- Characters not having a specific code are coded as z224U (in hex) -decode_num_esc d rest - = go (digitToInt d) rest - where - go n (c : rest) | isHexDigit c = go (16*n + digitToInt c) rest - go n ('U' : rest) = chr n : zDecodeString rest - go n other = error ("decode_num_esc: " ++ show n ++ ' ':other) - -decode_tuple :: Char -> EncodedString -> UserString -decode_tuple d rest - = go (digitToInt d) rest - where - -- NB. recurse back to zDecodeString after decoding the tuple, because - -- the tuple might be embedded in a longer name. - go n (c : rest) | isDigit c = go (10*n + digitToInt c) rest - go 0 ('T':rest) = "()" ++ zDecodeString rest - go n ('T':rest) = '(' : replicate (n-1) ',' ++ ")" ++ zDecodeString rest - go 1 ('H':rest) = "(# #)" ++ zDecodeString rest - go n ('H':rest) = '(' : '#' : replicate (n-1) ',' ++ "#)" ++ zDecodeString rest - go n other = error ("decode_tuple: " ++ show n ++ ' ':other) - -{- -Tuples are encoded as - Z3T or Z3H -for 3-tuples or unboxed 3-tuples respectively. No other encoding starts - Z - -* "(# #)" is the tycon for an unboxed 1-tuple (not 0-tuple) - There are no unboxed 0-tuples. - -* "()" is the tycon for a boxed 0-tuple. - There are no boxed 1-tuples. --} - -maybe_tuple :: UserString -> Maybe EncodedString - -maybe_tuple "(# #)" = Just("Z1H") -maybe_tuple ('(' : '#' : cs) = case count_commas (0::Int) cs of - (n, '#' : ')' : cs) -> Just ('Z' : shows (n+1) "H") - other -> Nothing -maybe_tuple "()" = Just("Z0T") -maybe_tuple ('(' : cs) = case count_commas (0::Int) cs of - (n, ')' : cs) -> Just ('Z' : shows (n+1) "T") - other -> Nothing -maybe_tuple other = Nothing - -count_commas :: Int -> String -> (Int, String) -count_commas n (',' : cs) = count_commas (n+1) cs -count_commas n cs = (n,cs)