Add some predicates and accessors to FlattenTypes.

[matthijs/master-project/cλash.git] / FlattenTypes.hs

diff --git a/FlattenTypes.hs b/FlattenTypes.hs
index af6289e6588371855c1dc0ef6ef8be838c73fc5a..ecad1badaa754382bc9c51b16b08f2532004d7a0 100644 (file)
--- a/FlattenTypes.hs
+++ b/FlattenTypes.hs
@@ -20,7 +20,7 @@ type SignalMap = HsValueMap SignalId
 type StateId = Int
 
 -- | How is a given (single) value in a function's type (ie, argument or
--- return value) used?
+--   return value) used?
 data HsValueUse = 
   Port           -- ^ Use it as a port (input or output)
   | State StateId -- ^ Use it as state (input or output). The int is used to
@@ -92,10 +92,36 @@ data SigDef =
   }
   -- | Unconditional signal definition
   | UncondDef {
-    defSrc :: SignalId,
+    defSrc :: Either SignalId SignalExpr,
     defDst :: SignalId
   } deriving (Show, Eq)
 
+-- | Is the given SigDef a FApp?
+is_FApp :: SigDef -> Bool
+is_FApp d = case d of  
+  (FApp _ _ _) -> True
+  _ -> False
+
+-- | Which signals are used by the given SigDef?
+sigDefUses :: SigDef -> [SignalId]
+sigDefUses (UncondDef (Left id) _) = [id]
+sigDefUses (UncondDef (Right expr) _) = sigExprUses expr
+sigDefUses (CondDef cond true false _) = [cond, true, false]
+sigDefUses (FApp _ args _) = concat $ map Foldable.toList args
+
+-- | An expression on signals
+data SignalExpr = 
+  EqLit SignalId String -- ^ Is the given signal equal to the given (VHDL) literal
+  | Literal String -- ^ A literal value
+  | Eq SignalId SignalId -- ^ A comparison between to signals
+  deriving (Show, Eq)
+
+-- | Which signals are used by the given SignalExpr?
+sigExprUses :: SignalExpr -> [SignalId]
+sigExprUses (EqLit id _) = [id]
+sigExprUses (Literal _) = []
+sigExprUses (Eq a b) = [a, b]
+
 -- Returns the function used by the given SigDef, if any
 usedHsFunc :: SigDef -> Maybe HsFunction
 usedHsFunc (FApp hsfunc _ _) = Just hsfunc
@@ -127,11 +153,20 @@ isInternalSigUse :: SigUse -> Bool
 isInternalSigUse SigInternal = True
 isInternalSigUse _ = False
 
+oldStateId :: SigUse -> Maybe StateId
+oldStateId (SigStateOld id) = Just id
+oldStateId _ = Nothing
+
+newStateId :: SigUse -> Maybe StateId
+newStateId (SigStateNew id) = Just id
+newStateId _ = Nothing
+
 -- | Information on a signal definition
 data SignalInfo = SignalInfo {
   sigName :: Maybe String,
   sigUse  :: SigUse,
-  sigTy   :: Type.Type
+  sigTy   :: Type.Type,
+  nameHints :: [String]
 }
 
 -- | A flattened function
@@ -150,6 +185,10 @@ signalInfo sigs id = Maybe.fromJust $ lookup id sigs
 -- | A list of binds in effect at a particular point of evaluation
 type BindMap = [(
   CoreBndr,            -- ^ The bind name
+  BindValue            -- ^ The value bound to it
+  )]
+
+type BindValue =
   Either               -- ^ The bind value which is either
     (SignalMap)
                        -- ^ a signal
@@ -157,7 +196,6 @@ type BindMap = [(
       HsValueUse,      -- ^ or a HighOrder function
       [SignalId]       -- ^ With these signals already applied to it
     )
-  )]
 
 -- | The state during the flattening of a single function
 type FlattenState = State.State ([SigDef], [(SignalId, SignalInfo)], SignalId)
@@ -173,6 +211,33 @@ genSignalId :: SigUse -> Type.Type -> FlattenState SignalId
 genSignalId use ty = do
   (defs, sigs, n) <- State.get
   -- Generate a new numbered but unnamed signal
-  let s = (n, SignalInfo Nothing use ty)
+  let s = (n, SignalInfo Nothing use ty [])
   State.put (defs, s:sigs, n+1)
   return n
+
+-- | Add a name hint to the given signal
+addNameHint :: String -> SignalId -> FlattenState ()
+addNameHint hint id = do
+  info <- getSignalInfo id
+  let hints = nameHints info
+  if hint `elem` hints
+    then do
+      return ()
+    else do
+      let hints' = (hint:hints)
+      setSignalInfo id (info {nameHints = hints'})
+
+-- | Returns the SignalInfo for the given signal. Errors if the signal is not
+--   known in the session.
+getSignalInfo :: SignalId -> FlattenState SignalInfo
+getSignalInfo id = do
+  (defs, sigs, n) <- State.get
+  return $ signalInfo sigs id
+
+setSignalInfo :: SignalId -> SignalInfo -> FlattenState ()
+setSignalInfo id' info' = do
+  (defs, sigs, n) <- State.get
+  let sigs' = map (\(id, info) -> (id, if id == id' then info' else info)) sigs
+  State.put (defs, sigs', n)
+
+-- vim: set ts=8 sw=2 sts=2 expandtab: