X-Git-Url: https://git.stderr.nl/gitweb?a=blobdiff_plain;f=FlattenTypes.hs;h=bcb8be7d55d8e17a762b13e50d4314ab8a512b9b;hb=89dda45ec76981b8f3b84cac1537b776df479efa;hp=e7d21d605c5fec8901e9ad104cb4f92f8f3c3849;hpb=157dae90bdd7c45613c6ad6185383a1137b2323f;p=matthijs%2Fmaster-project%2Fc%CE%BBash.git

diff --git a/FlattenTypes.hs b/FlattenTypes.hs
index e7d21d6..bcb8be7 100644
--- a/FlattenTypes.hs
+++ b/FlattenTypes.hs
@@ -1,5 +1,6 @@
 module FlattenTypes where
 
+import qualified Maybe
 import Data.Traversable
 import qualified Data.Foldable as Foldable
 import qualified Control.Monad.State as State
@@ -10,16 +11,19 @@ import qualified Type
 import HsValueMap
 
 -- | A signal identifier
-type UnnamedSignal = Int
+type SignalId = Int
 
 -- | A map of a Haskell value to signal ids
-type SignalMap sigid = HsValueMap sigid
+type SignalMap = HsValueMap SignalId
+
+-- | A state identifier
+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 Int    -- ^ Use it as state (input or output). The int is used to
+  | State StateId -- ^ Use it as state (input or output). The int is used to
                  --   match input state to output state.
   | HighOrder {  -- ^ Use it as a high order function input
     hoName :: String,  -- ^ Which function is passed in?
@@ -71,27 +75,57 @@ hasState hsfunc =
   any (Foldable.any isStateUse) (hsFuncArgs hsfunc)
   || Foldable.any isStateUse (hsFuncRes hsfunc)
 
--- | A flattened function application
-data FApp sigid = FApp {
-  appFunc :: HsFunction,
-  appArgs :: [SignalMap sigid],
-  appRes  :: SignalMap sigid
-} deriving (Show, Eq)
-
--- | A conditional signal definition
-data CondDef sigid = CondDef {
-  cond    :: sigid,
-  high    :: sigid,
-  low     :: sigid,
-  condRes :: sigid
-} deriving (Show, Eq)
+-- | Something that defines a signal
+data SigDef =
+  -- | A flattened function application
+  FApp {
+    appFunc :: HsFunction,
+    appArgs :: [SignalMap],
+    appRes  :: SignalMap
+  }
+  -- | A conditional signal definition
+  | CondDef {
+    cond    :: SignalId,
+    high    :: SignalId,
+    low     :: SignalId,
+    condRes :: SignalId
+  }
+  -- | Unconditional signal definition
+  | UncondDef {
+    defSrc :: SignalId,
+    defDst :: SignalId
+  } deriving (Show, Eq)
+
+-- Returns the function used by the given SigDef, if any
+usedHsFunc :: SigDef -> Maybe HsFunction
+usedHsFunc (FApp hsfunc _ _) = Just hsfunc
+usedHsFunc _ = Nothing
 
 -- | How is a given signal used in the resulting VHDL?
 data SigUse = 
-  SigPort         -- | Use as a port
-  | SigInternal   -- | Use as an internal signal
-  | SigState      -- | Use as an internal state
-  | SigSubState   -- | Do not use, state variable is used in a subcircuit
+  SigPortIn          -- | Use as an input port
+  | SigPortOut       -- | Use as an input port
+  | SigInternal      -- | Use as an internal signal
+  | SigStateOld StateId  -- | Use as the current internal state
+  | SigStateNew StateId  -- | Use as the new internal state
+  | SigSubState      -- | Do not use, state variable is used in a subcircuit
+
+-- | Is this a port signal use?
+isPortSigUse :: SigUse -> Bool
+isPortSigUse SigPortIn = True
+isPortSigUse SigPortOut = True
+isPortSigUse _ = False
+
+-- | Is this a state signal use? Returns false for substate.
+isStateSigUse :: SigUse -> Bool
+isStateSigUse (SigStateOld _) = True
+isStateSigUse (SigStateNew _) = True
+isStateSigUse _ = False
+
+-- | Is this an internal signal use?
+isInternalSigUse :: SigUse -> Bool
+isInternalSigUse SigInternal = True
+isInternalSigUse _ = False
 
 -- | Information on a signal definition
 data SignalInfo = SignalInfo {
@@ -101,49 +135,44 @@ data SignalInfo = SignalInfo {
 }
 
 -- | A flattened function
-data FlatFunction' sigid = FlatFunction {
-  flat_args   :: [SignalMap sigid],
-  flat_res    :: SignalMap sigid,
-  flat_apps   :: [FApp sigid],
-  flat_conds  :: [CondDef sigid],
-  flat_sigs   :: [(sigid, SignalInfo)]
+data FlatFunction = FlatFunction {
+  flat_args   :: [SignalMap],
+  flat_res    :: SignalMap,
+  flat_defs   :: [SigDef],
+  flat_sigs   :: [(SignalId, SignalInfo)]
 }
 
--- | A flat function that does not have its signals named
-type FlatFunction = FlatFunction' UnnamedSignal
+-- | Lookup a given signal id in a signal map, and return the associated
+--   SignalInfo. Errors out if the signal was not found.
+signalInfo :: [(SignalId, SignalInfo)] -> SignalId -> SignalInfo
+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
   Either               -- ^ The bind value which is either
-    (SignalMap UnnamedSignal)
+    (SignalMap)
                        -- ^ a signal
     (
       HsValueUse,      -- ^ or a HighOrder function
-      [UnnamedSignal]  -- ^ With these signals already applied to it
+      [SignalId]       -- ^ With these signals already applied to it
     )
   )]
 
 -- | The state during the flattening of a single function
-type FlattenState = State.State ([FApp UnnamedSignal], [CondDef UnnamedSignal], [(UnnamedSignal, SignalInfo)], UnnamedSignal)
+type FlattenState = State.State ([SigDef], [(SignalId, SignalInfo)], SignalId)
 
 -- | Add an application to the current FlattenState
-addApp :: (FApp UnnamedSignal) -> FlattenState ()
-addApp a = do
-  (apps, conds, sigs, n) <- State.get
-  State.put (a:apps, conds, sigs, n)
-
--- | Add a conditional definition to the current FlattenState
-addCondDef :: (CondDef UnnamedSignal) -> FlattenState ()
-addCondDef c = do
-  (apps, conds, sigs, n) <- State.get
-  State.put (apps, c:conds, sigs, n)
+addDef :: SigDef -> FlattenState ()
+addDef d = do
+  (defs, sigs, n) <- State.get
+  State.put (d:defs, sigs, n)
 
 -- | Generates a new signal id, which is unique within the current flattening.
-genSignalId :: SigUse -> Type.Type -> FlattenState UnnamedSignal 
+genSignalId :: SigUse -> Type.Type -> FlattenState SignalId 
 genSignalId use ty = do
-  (apps, conds, sigs, n) <- State.get
+  (defs, sigs, n) <- State.get
   -- Generate a new numbered but unnamed signal
   let s = (n, SignalInfo Nothing use ty)
-  State.put (apps, conds, s:sigs, n+1)
+  State.put (defs, s:sigs, n+1)
   return n