7679113 · text · git.iko.soy

Make encoding slightly faster.

The improvement mainly comes from dropping a redundant check when decoding an ASCII byte.

commit7679113c8d232d36b4a14ae47b01bd72d13795ec authorBryan O'Sullivan <bos@serpentine.com> dateThu 22 Dec 2011, 23:53 (15 years ago) parent049278d

1 file changed+2−4

unifiedsplit

Data/Text/Encoding.hs+2−4

@@ -154,7 +154,7 @@ encodeUtf8 (Text arr off len) = unsafePerformIO $ do

154154 loop n1 m1 ptr = go n1 m1

155155 where

156156 go !n !m

157− | n-off == len = return (PS fp 0 m)

157+ | n == off+len = return (PS fp 0 m)

158158 | otherwise = do

159159 let poke8 k v = poke (ptr `plusPtr` k) (fromIntegral v :: Word8)

160160 ensure k act

@@ -167,9 +167,7 @@ encodeUtf8 (Text arr off len) = unsafePerformIO $ do

167167 start newSize n m fp'

168168 {-# INLINE ensure #-}

169169 case A.unsafeIndex arr n of

170− w| w <= 0x7F -> ensure 1 $ do

171− poke8 m w

172− go (n+1) (m+1)

170+ w| w <= 0x7F -> poke8 m w >> go (n+1) (m+1)

173171 | w <= 0x7FF -> ensure 2 $ do

174172 poke8 m $ (w `shiftR` 6) + 0xC0

175173 poke8 (m+1) $ (w .&. 0x3f) + 0x80