[commit: ghc] master: Speed improvement to LLVM Mangler for large sections. (2f8ef8f)

[David Terei]

Repository : ssh://darcs.haskell.org//srv/darcs/ghc

On branch  : master

http://hackage.haskell.org/trac/ghc/changeset/2f8ef8f701954dc5f145dbabe11f80ba2bed45db

>---------------------------------------------------------------

commit 2f8ef8f701954dc5f145dbabe11f80ba2bed45db
Author: David Terei <davidterei at gmail.com>
Date:   Sat Jun 25 11:33:14 2011 -0700

    Speed improvement to LLVM Mangler for large sections.
    
    Patch by Peter Wortmann!

>---------------------------------------------------------------

 compiler/llvmGen/LlvmMangler.hs |   17 +++++++++--------
 1 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/compiler/llvmGen/LlvmMangler.hs b/compiler/llvmGen/LlvmMangler.hs
index 591ef81..4f61a93 100644
--- a/compiler/llvmGen/LlvmMangler.hs
+++ b/compiler/llvmGen/LlvmMangler.hs
@@ -71,7 +71,7 @@ llvmFixupAsm f1 f2 = do
 -}
 fixTables :: Handle -> Handle -> I.IntMap B.ByteString -> IO ()
 fixTables r w m = do
-    f <- getFun r B.empty
+    f <- getFun r
     if B.null f
        then return ()
        else let fun    = fixupStack f B.empty
@@ -92,13 +92,14 @@ fixTables r w m = do
             in mapM_ (B.hPut w) bs >> fixTables r w m'
 
 -- | Read in the next function/data defenition
-getFun :: Handle -> B.ByteString -> IO B.ByteString
-getFun r f = do
-    l <- (try (B.hGetLine r))::IO (Either IOError B.ByteString)
-    case l of
-        Right l' | B.null l' -> return f
-                 | otherwise -> getFun r (f `B.append` newLine `B.append` l')
-        Left _ -> return B.empty
+getFun :: Handle -> IO B.ByteString
+getFun r = go [] >>= return . B.intercalate newLine
+    where go ls = do
+        l <- (try (B.hGetLine r))::IO (Either IOError B.ByteString)
+        case l of
+            Right l' | B.null l' -> (return B.empty : reverse ls)
+                     | otherwise -> go (l':ls)
+            Left _ -> return []
 
 {-|
     Mac OS X requires that the stack be 16 byte aligned when making a function