Mark all signals as ports or states when appropriate.

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

diff --git a/FlattenTypes.hs b/FlattenTypes.hs
index 7838dcdcbc28563fa7f77d54063e21183b9a3cd6..ce1f22dc00bbece034db0108d6ae6b6f52217cc0 100644 (file)
--- a/FlattenTypes.hs
+++ b/FlattenTypes.hs
@@ -1,9 +1,12 @@
 module FlattenTypes where
 
+import qualified Maybe
 import Data.Traversable
+import qualified Data.Foldable as Foldable
 import qualified Control.Monad.State as State
 
 import CoreSyn
+import qualified Type
 
 import HsValueMap
 
@@ -27,6 +30,11 @@ data HsValueUse =
   }
   deriving (Show, Eq, Ord)
 
+-- | Is this HsValueUse a state use?
+isStateUse :: HsValueUse -> Bool
+isStateUse (State _) = True
+isStateUse _         = False
+
 -- | A map from a Haskell value to the use of each single value
 type HsUseMap = HsValueMap HsValueUse
 
@@ -59,6 +67,11 @@ data HsFunction = HsFunction {
   hsFuncRes  :: HsUseMap
 } deriving (Show, Eq, Ord)
 
+hasState :: HsFunction -> Bool
+hasState hsfunc = 
+  any (Foldable.any isStateUse) (hsFuncArgs hsfunc)
+  || Foldable.any isStateUse (hsFuncRes hsfunc)
+
 -- | A flattened function application
 data FApp sigid = FApp {
   appFunc :: HsFunction,
@@ -74,19 +87,35 @@ data CondDef sigid = CondDef {
   condRes :: sigid
 } deriving (Show, Eq)
 
+-- | How is a given signal used in the resulting VHDL?
+data SigUse = 
+  SigPortIn          -- | Use as an input port
+  | SigPortOut       -- | Use as an input port
+  | SigInternal      -- | Use as an internal signal
+  | SigStateOld Int  -- | Use as the current internal state
+  | SigStateNew Int  -- | Use as the new internal state
+  | SigSubState      -- | Do not use, state variable is used in a subcircuit
+
 -- | Information on a signal definition
 data SignalInfo = SignalInfo {
-  name :: Maybe String
-} deriving (Eq, Show)
+  sigName :: Maybe String,
+  sigUse  :: SigUse,
+  sigTy   :: Type.Type
+}
 
 -- | A flattened function
 data FlatFunction' sigid = FlatFunction {
-  args   :: [SignalMap sigid],
-  res    :: SignalMap sigid,
-  apps   :: [FApp sigid],
-  conds  :: [CondDef sigid],
-  sigs   :: [(sigid, SignalInfo)]
-} deriving (Show, Eq)
+  flat_args   :: [SignalMap sigid],
+  flat_res    :: SignalMap sigid,
+  flat_apps   :: [FApp sigid],
+  flat_conds  :: [CondDef sigid],
+  flat_sigs   :: [(sigid, SignalInfo)]
+}
+
+-- | Lookup a given signal id in a signal map, and return the associated
+--   SignalInfo. Errors out if the signal was not found.
+signalInfo :: Eq sigid => [(sigid, SignalInfo)] -> sigid -> SignalInfo
+signalInfo sigs id = Maybe.fromJust $ lookup id sigs
 
 -- | A flat function that does not have its signals named
 type FlatFunction = FlatFunction' UnnamedSignal
@@ -119,10 +148,10 @@ addCondDef c = do
   State.put (apps, c:conds, sigs, n)
 
 -- | Generates a new signal id, which is unique within the current flattening.
-genSignalId :: FlattenState UnnamedSignal 
-genSignalId = do
+genSignalId :: SigUse -> Type.Type -> FlattenState UnnamedSignal 
+genSignalId use ty = do
   (apps, conds, sigs, n) <- State.get
   -- Generate a new numbered but unnamed signal
-  let s = (n, SignalInfo Nothing)
+  let s = (n, SignalInfo Nothing use ty)
   State.put (apps, conds, s:sigs, n+1)
   return n