Generate renderer functions using TH

These take (and project from) a data type instead of hash maps, _and_
use text-builder-linear, _and_ have the full template inlined. The
result is that this is the fastest renderer yet.

1 files changed, 37 insertions, 0 deletions

diff --git a/escapexml/EscapeXML.hs b/escapexml/EscapeXML.hs
new file mode 100644
index 0000000..662d2ed
--- /dev/null
+++ b/escapexml/EscapeXML.hs
@@ -0,0 +1,37 @@
+{-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE MagicHash #-}
+{-# LANGUAGE UnboxedTuples #-}
+{-# LANGUAGE UnliftedFFITypes #-}
+module EscapeXML (escapeXML) where
+
+import Data.Array.Byte
+import Data.Text.Internal
+import Foreign.C.Types
+import GHC.Exts
+import GHC.IO (IO(IO))
+import System.IO.Unsafe (unsafePerformIO)
+
+
+foreign import ccall unsafe "tirclogv_escapexml_len"
+  c_escapexml_len :: ByteArray# -> CSize -> CSize -> IO CSize
+
+foreign import ccall unsafe "tirclogv_escapexml"
+  c_escapexml :: MutableByteArray# RealWorld -> ByteArray# -> CSize -> CSize -> IO ()
+
+{-# NOINLINE escapeXML #-}
+escapeXML :: Text -> Text
+escapeXML (Text (ByteArray src#) off len) = unsafePerformIO $ do
+  let offCS = fromIntegral @Int @CSize off
+      lenCS = fromIntegral @Int @CSize len
+
+  reslen <- c_escapexml_len src# offCS lenCS
+  let !reslenI@(I# reslen#) = fromIntegral @CSize @Int reslen
+
+  MutableByteArray dst# <-
+    IO $ \s -> case newByteArray# reslen# s of
+                 (# s', mba# #) -> (# s', MutableByteArray mba# #)
+  c_escapexml dst# src# offCS lenCS
+  ba <- IO $ \s -> case unsafeFreezeByteArray# dst# s of
+                     (# s', ba# #) -> (# s', ByteArray ba# #)
+
+  return (Text ba 0 reslenI)