X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2FcoreSyn%2FCorePrep.lhs;h=8b0499c16d20e40099fc9c7ac4056941623274c5;hp=4db4c53d569f1dab58ccebec1dafc54f6ce13235;hb=9a81ddfb43b96cfeae2236c9616ca3552250b235;hpb=2cda6f9f6c68f5cfd202e9979fefaa40df26769e

diff --git a/compiler/coreSyn/CorePrep.lhs b/compiler/coreSyn/CorePrep.lhs
index 4db4c53..8b0499c 100644
--- a/compiler/coreSyn/CorePrep.lhs
+++ b/compiler/coreSyn/CorePrep.lhs
@@ -278,7 +278,7 @@ cpeBind top_lvl env (Rec pairs)
        ; stuff <- zipWithM (cpePair top_lvl Recursive False env') bndrs1 rhss
 
        ; let (floats_s, bndrs2, rhss2) = unzip3 stuff
-             all_pairs = foldrOL add_float (bndrs1 `zip` rhss2)
+             all_pairs = foldrOL add_float (bndrs2 `zip` rhss2)
 	     	       	 	 	   (concatFloats floats_s)
        ; return (extendCorePrepEnvList env (bndrs `zip` bndrs2),
        	 	 unitFloat (FloatLet (Rec all_pairs))) }
@@ -310,9 +310,13 @@ cpePair top_lvl is_rec is_strict_or_unlifted env bndr rhs
 		        ; let float = mkFloat False False v rhs2
 		        ; return (addFloat floats2 float, cpeEtaExpand arity (Var v)) })
 
-	     	-- Record if the binder is evaluated
+     	-- Record if the binder is evaluated
+	-- and otherwise trim off the unfolding altogether
+	-- It's not used by the code generator; getting rid of it reduces
+	-- heap usage and, since we may be changing uniques, we'd have
+	-- to substitute to keep it right
        ; let bndr' | exprIsHNF rhs' = bndr `setIdUnfolding` evaldUnfolding
-       	     	   | otherwise      = bndr
+       	     	   | otherwise      = bndr `setIdUnfolding` noUnfolding
 
        ; return (floats3, bndr', rhs') }
   where