Fix bug in case vectorisation

diff --git a/compiler/vectorise/Vectorise.hs b/compiler/vectorise/Vectorise.hs
index 96ed01e..9f2e2b7 100644 (file)
--- a/compiler/vectorise/Vectorise.hs
+++ b/compiler/vectorise/Vectorise.hs
@@ -435,7 +435,9 @@ packLiftingContext len shape tag fvs res_ty p
       lc_var <- builtin liftingContext
       localV $
         do
-          bnds <- mapM (packFreeVar (Var lc_var) (Var sel_var)) (varSetElems fvs)
+          bnds <- mapM (packFreeVar (Var lc_var) (Var sel_var))
+                . filter isLocalId
+                $ varSetElems fvs
           (vexpr, lexpr) <- p
           return (vexpr, Let (NonRec sel_var sel_expr)
                          $ Case len lc_var res_ty [(DEFAULT, [], lexpr)])