From: Matthijs Kooijman <m.kooijman@student.utwente.nl>
Date: Tue, 17 Feb 2009 16:36:27 +0000 (+0100)
Subject: Don't generate ports for non-port signals.
X-Git-Url: https://git.stderr.nl/gitweb?a=commitdiff_plain;h=7bb29e6c00a94229f48663afb6e128d24b3ad7f9;p=matthijs%2Fmaster-project%2Fc%CE%BBash.git

Don't generate ports for non-port signals.

This allows an entry in a VHDLSignalmap to be empty, which allows for
arguments and results that do not expand into a port, such as state.
---

diff --git a/Translator.hs b/Translator.hs
index 9cced34..f875dd6 100644
--- a/Translator.hs
+++ b/Translator.hs
@@ -209,7 +209,7 @@ data BuiltIn = BuiltIn String [PortMap] PortMap
 -- | Map a port specification of a builtin function to a VHDL Signal to put in
 --   a VHDLSignalMap
 toVHDLSignalMap :: HsValueMap (String, AST.TypeMark) -> VHDLSignalMap
-toVHDLSignalMap = fmap (\(name, ty) -> (VHDL.mkVHDLId name, ty))
+toVHDLSignalMap = fmap (\(name, ty) -> Just (VHDL.mkVHDLId name, ty))
 
 -- | Translate a concise representation of a builtin function to something
 --   that can be put into FuncMap directly.
diff --git a/VHDL.hs b/VHDL.hs
index 5f7face..9516fdd 100644
--- a/VHDL.hs
+++ b/VHDL.hs
@@ -59,9 +59,13 @@ createEntity hsfunc fdata =
       in
         setEntity hsfunc entity'
   where
-    mkMap :: Eq id => [(id, SignalInfo)] -> id -> (AST.VHDLId, AST.TypeMark)
+    mkMap :: Eq id => [(id, SignalInfo)] -> id -> Maybe (AST.VHDLId, AST.TypeMark)
     mkMap sigmap id =
-      (mkVHDLId nm, vhdl_ty ty)
+      if isPortSigUse $ sigUse info
+        then
+          Just (mkVHDLId nm, vhdl_ty ty)
+        else
+          Nothing
       where
         info = Maybe.fromMaybe
           (error $ "Signal not found in the name map? This should not happen!")
@@ -87,7 +91,7 @@ createEntityAST hsfunc args res =
             ++ clk_port
     mapToPorts :: AST.Mode -> VHDLSignalMap -> [AST.IfaceSigDec] 
     mapToPorts mode m =
-      map (mkIfaceSigDec mode) (Foldable.toList m)
+      Maybe.catMaybes $ map (mkIfaceSigDec mode) (Foldable.toList m)
     -- Add a clk port if we have state
     clk_port = if hasState hsfunc
       then
@@ -98,10 +102,11 @@ createEntityAST hsfunc args res =
 -- | Create a port declaration
 mkIfaceSigDec ::
   AST.Mode                         -- | The mode for the port (In / Out)
-  -> (AST.VHDLId, AST.TypeMark)    -- | The id and type for the port
-  -> AST.IfaceSigDec               -- | The resulting port declaration
+  -> Maybe (AST.VHDLId, AST.TypeMark)    -- | The id and type for the port
+  -> Maybe AST.IfaceSigDec               -- | The resulting port declaration
 
-mkIfaceSigDec mode (id, ty) = AST.IfaceSigDec id mode ty
+mkIfaceSigDec mode (Just (id, ty)) = Just $ AST.IfaceSigDec id mode ty
+mkIfaceSigDec _ Nothing = Nothing
 
 -- | Generate a VHDL entity name for the given hsfunc
 mkEntityId hsfunc =
@@ -197,7 +202,7 @@ mkAssocElems ::
 
 mkAssocElems sigmap app entity =
     -- Create the actual AssocElems
-    zipWith mkAssocElem ports sigs
+    Maybe.catMaybes $ zipWith mkAssocElem ports sigs
   where
     -- Turn the ports and signals from a map into a flat list. This works,
     -- since the maps must have an identical form by definition. TODO: Check
@@ -207,7 +212,7 @@ mkAssocElems sigmap app entity =
     arg_sigs  = (concat (map Foldable.toList (appArgs app)))
     res_sigs  = Foldable.toList (appRes app)
     -- Extract the id part from the (id, type) tuple
-    ports     = (map fst (arg_ports ++ res_ports)) 
+    ports     = (map (fmap fst) (arg_ports ++ res_ports)) 
     -- Translate signal numbers into names
     sigs      = (map (lookupSigName sigmap) (arg_sigs ++ res_sigs))
 
@@ -223,8 +228,9 @@ lookupSigName sigs sig = name
       (sigName info)
 
 -- | Create an VHDL port -> signal association
-mkAssocElem :: AST.VHDLId -> String -> AST.AssocElem
-mkAssocElem port signal = Just port AST.:=>: (AST.ADName (AST.NSimple (mkVHDLId signal))) 
+mkAssocElem :: Maybe AST.VHDLId -> String -> Maybe AST.AssocElem
+mkAssocElem (Just port) signal = Just $ Just port AST.:=>: (AST.ADName (AST.NSimple (mkVHDLId signal))) 
+mkAssocElem Nothing _ = Nothing
 
 -- | Extracts the generated entity id from the given funcdata
 getEntityId :: FuncData -> Maybe AST.VHDLId
diff --git a/VHDLTypes.hs b/VHDLTypes.hs
index 9ae197c..1704bb8 100644
--- a/VHDLTypes.hs
+++ b/VHDLTypes.hs
@@ -7,7 +7,9 @@ import qualified ForSyDe.Backend.VHDL.AST as AST
 
 import FlattenTypes
 
-type VHDLSignalMap = SignalMap (AST.VHDLId, AST.TypeMark)
+-- | A mapping from a haskell structure to the corresponding VHDL port
+--   signature, or Nothing for values that do not translate to a port.
+type VHDLSignalMap = SignalMap (Maybe (AST.VHDLId, AST.TypeMark))
 
 -- A description of a VHDL entity. Contains both the entity itself as well as
 -- info on how to map a haskell value (argument / result) on to the entity's