X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=GHC%2FFloat.lhs;h=cac8c0af164770f98753ff95c794ef38a5f29151;hb=91adf39c07706a188278aa6983e9b4f1ea4f400f;hp=9831ec90f35a7ff8e52872c75503826c77b9e762;hpb=aaf764b3ad8b1816d68b5f27299eac125f08e1a5;p=haskell-directory.git

diff --git a/GHC/Float.lhs b/GHC/Float.lhs
index 9831ec9..cac8c0a 100644
--- a/GHC/Float.lhs
+++ b/GHC/Float.lhs
@@ -16,6 +16,7 @@
 
 #include "ieee-flpt.h"
 
+-- #hide
 module GHC.Float( module GHC.Float, Float#, Double# )  where
 
 import Data.Maybe
@@ -188,10 +189,13 @@ instance  Num Float  where
 	     | otherwise = negate 1
 
     {-# INLINE fromInteger #-}
-    fromInteger n	=  encodeFloat n 0
-	-- It's important that encodeFloat inlines here, and that 
-	-- fromInteger in turn inlines,
-	-- so that if fromInteger is applied to an (S# i) the right thing happens
+    fromInteger (S# i#)    = case (int2Float# i#) of { d# -> F# d# }
+    fromInteger (J# s# d#) = encodeFloat# s# d# 0
+	-- previous code: fromInteger n	= encodeFloat n 0
+	-- doesn't work too well, because encodeFloat is defined in
+	-- terms of ccalls which can never be simplified away.  We
+	-- want simple literals like (fromInteger 3 :: Float) to turn
+	-- into (F# 3.0), hence the special case for S# here.
 
 instance  Real Float  where
     toRational x	=  (m%1)*(b%1)^^n