+data Shape = Shape {
+ shapeReprTys :: [Type]
+ , shapeStrictness :: [StrictnessMark]
+ , shapeLength :: [CoreExpr] -> VM CoreExpr
+ , shapeReplicate :: CoreExpr -> CoreExpr -> VM [CoreExpr]
+ }
+
+tyConShape :: TyCon -> VM Shape
+tyConShape vect_tc
+ | isProductTyCon vect_tc
+ = return $ Shape {
+ shapeReprTys = [intPrimTy]
+ , shapeStrictness = [NotMarkedStrict]
+ , shapeLength = \[len] -> return len
+ , shapeReplicate = \len _ -> return [len]
+ }
+
+ | otherwise
+ = do
+ repr_ty <- mkPArrayType intTy -- FIXME: we want to unbox this
+ return $ Shape {
+ shapeReprTys = [repr_ty]
+ , shapeStrictness = [MarkedStrict]
+ , shapeLength = \[sel] -> lengthPA sel
+ , shapeReplicate = \len n -> do
+ e <- replicatePA len n
+ return [e]
+ }
+