globally imported items are selectively nested

src/Convert/NestPI.hs

@@ -31,6 +31,7 @@ convert =
                     (traverseDescriptions . convertDescription)
                     curr
         isPI :: Description -> Bool
+        isPI (PackageItem Import{}) = False
         isPI (PackageItem item) = piName item /= Nothing
         isPI _ = False
 
@@ -55,8 +56,7 @@ convertDescription pis (orig @ Part{}) =
             , collectTypesM $ collectNestedTypesM collectTypenamesM
             , collectExprsM $ collectNestedExprsM collectIdentsM
             ]
-        neededPIs = Set.difference (Set.union usedPIs imports) existingPIs
-        imports = Map.keysSet $ Map.filter isImport pis
+        neededPIs = Set.difference usedPIs existingPIs
         newItems = map MIPackageItem $ Map.elems $
             Map.restrictKeys pis neededPIs
         -- place data declarations at the beginning to obey declaration
@@ -104,7 +104,3 @@ piName (Decl (CommentDecl          _)) = Nothing
 piName (Import x y) = Just $ show $ Import x y
 piName (Export    _) = Nothing
 piName (Directive _) = Nothing
-
-isImport :: PackageItem -> Bool
-isImport Import{} = True
-isImport _ = False

src/Convert/Package.hs

@@ -53,7 +53,7 @@ convertFile :: Packages -> AST -> AST
 convertFile packages ast =
     (++) globalItems $
     filter (not . isCollected) $
-    traverseDescriptions (traverseDescription packages) $
+    concatMap (traverseDescription packages) $
     ast
     where
         globalItems = map PackageItem $
@@ -127,11 +127,20 @@ collectDescriptionM (Package _ name items) =
         isImport _ = False
 collectDescriptionM _ = return ()
 
-traverseDescription :: Packages -> Description -> Description
+traverseDescription :: Packages -> Description -> [Description]
+traverseDescription packages (PackageItem (Import x y)) =
+    map (\(MIPackageItem item) -> PackageItem item) items
+    where
+        orig = Part [] False Module Inherit "DNE" []
+            [MIPackageItem $ Import x y]
+        [orig'] = traverseDescription packages orig
+        Part [] False Module Inherit "DNE" [] items = orig'
 traverseDescription packages description =
-    traverseModuleItems (traverseModuleItem existingItemNames packages)
-    description
+    [description']
     where
+        description' = traverseModuleItems
+            (traverseModuleItem existingItemNames packages)
+            description
         existingItemNames = execWriter $
             collectModuleItemsM writePIName description
         writePIName :: ModuleItem -> Writer Idents ()

test/basic/unused_imports.sv

+package P;
+    localparam FOO = 1;
+    localparam BAR = 2;
+endpackage
+import P::*;
+module top;
+    initial $display(FOO);
+endmodule

test/basic/unused_imports.v

+module top;
+    localparam FOO = 1;
+    initial $display(FOO);
+endmodule