getFieldLabels has better error messages

[matthijs/master-project/cλash.git] / clash / CLasH / VHDL / VHDLTools.hs

diff --git a/clash/CLasH/VHDL/VHDLTools.hs b/clash/CLasH/VHDL/VHDLTools.hs
index a70036ef33b56ff60816390b43505b7f7fcb6e77..ab3360b8126c44950c2f9cabddf71f73f38ef0ee 100644 (file)
--- a/clash/CLasH/VHDL/VHDLTools.hs
+++ b/clash/CLasH/VHDL/VHDLTools.hs
@@ -346,7 +346,8 @@ mkHTypeEither' ty | ty_has_free_tyvars ty = return $ Left $ "\nVHDLTools.mkHType
                   return $ Right $ SizedIType len
                 "Index" -> do
                   bound <- tfp_to_int (ranged_word_bound_ty ty)
-                  return $ Right $ RangedWType bound
+                  -- Upperbound is exclusive, hence the -1
+                  return $ Right $ RangedWType (bound - 1)
                 otherwise ->
                   mkTyConHType tycon args
     Nothing -> return $ Left $ "\nVHDLTools.mkHTypeEither': Do not know what to do with type: " ++ pprString ty
@@ -570,8 +571,8 @@ getFields ::
 getFields htype dc_i = case htype of
   (AggrType name _ fieldss) 
     | dc_i >= 0 && dc_i < length fieldss -> fieldss!!dc_i
-    | otherwise -> error $ "Invalid constructor index: " ++ (show dc_i) ++ ". No such constructor in HType: " ++ (show htype)
-  _ -> error $ "Can't get fields from non-aggregate HType: " ++ show htype
+    | otherwise -> error $ "VHDLTool.getFields: Invalid constructor index: " ++ (show dc_i) ++ ". No such constructor in HType: " ++ (show htype)
+  _ -> error $ "VHDLTool.getFields: Can't get fields from non-aggregate HType: " ++ show htype
 
 -- Finds the field labels for an aggregation type, as VHDLIds.
 getFieldLabels ::