X-Git-Url: https://git.stderr.nl/gitweb?a=blobdiff_plain;f=c%CE%BBash%2FCLasH%2FNormalize.hs;h=e97e425c6e023bfc8ea9939c4f32f5bbc092a58e;hb=ce763aa6019c7076e4b8225cc25f27b46371b662;hp=1dc20f57051381b0a513448870dc3bed2b2a55d6;hpb=5d58ff471df987d8def34a473103c785890510c6;p=matthijs%2Fmaster-project%2Fc%CE%BBash.git

diff --git "a/c\316\273ash/CLasH/Normalize.hs" "b/c\316\273ash/CLasH/Normalize.hs"
index 1dc20f5..e97e425 100644
--- "a/c\316\273ash/CLasH/Normalize.hs"
+++ "b/c\316\273ash/CLasH/Normalize.hs"
@@ -406,15 +406,14 @@ funextract c expr = return expr
 -- Make sure the scrutinee of a case expression is a local variable
 -- reference.
 scrutsimpl :: Transform
--- Don't touch scrutinees that are already simple
-scrutsimpl c expr@(Case (Var _) _ _ _) = return expr
--- Replace all other cases with a let that binds the scrutinee and a new
+-- Replace a case expression with a let that binds the scrutinee and a new
 -- simple scrutinee, but only when the scrutinee is representable (to prevent
 -- loops with inlinenonrep, though I don't think a non-representable scrutinee
--- will be supported anyway...) 
+-- will be supported anyway...) and is not a local variable already.
 scrutsimpl c expr@(Case scrut b ty alts) = do
   repr <- isRepr scrut
-  if repr
+  local_var <- Trans.lift $ is_local_var scrut
+  if repr && not local_var
     then do
       id <- Trans.lift $ mkBinderFor scrut "scrut"
       change $ Let (NonRec id scrut) (Case (Var id) b ty alts)
@@ -817,6 +816,10 @@ inlinenonrepresult context expr | not (is_fun expr) =
 -- Leave all other expressions unchanged
 inlinenonrepresult c expr = return expr
 
+----------------------------------------------------------------
+-- Type-class transformations
+----------------------------------------------------------------
+
 --------------------------------
 -- ClassOp resolution
 --------------------------------