+ flattenSingleAltCaseExpr binds scrut b alt@(DataAlt datacon, bind_vars, expr) =
+ if DataCon.isTupleCon datacon
+ then do
+ -- Unpack the scrutinee (which must be a variable bound to a tuple) in
+ -- the existing bindings list and get the portname map for each of
+ -- it's elements.
+ let Tuple tuple_sigs = scrut
+ -- Add name hints to the returned signals
+ let binder_name = Name.getOccString b
+ Monad.zipWithM (\name sigs -> Traversable.mapM (addNameHint $ Name.getOccString name) sigs) bind_vars tuple_sigs
+ -- Merge our existing binds with the new binds.
+ let binds' = (zip bind_vars (map Left tuple_sigs)) ++ binds
+ -- Expand the expression with the new binds list
+ flattenExpr binds' expr
+ else
+ if null bind_vars
+ then
+ -- DataAlts without arguments don't need processing
+ -- (flattenMultipleAltCaseExpr will have done this already).
+ flattenExpr binds expr
+ else
+ error $ "Dataconstructors other than tuple constructors cannot have binder arguments in case pattern of alternative: " ++ (showSDoc $ ppr alt)
+
+ flattenSingleAltCaseExpr binds _ _ alt@(DEFAULT, [], expr) =
+ flattenExpr binds expr
+
+ flattenSingleAltCaseExpr _ _ _ alt = error $ "Case patterns other than data constructors not supported in case alternative: " ++ (showSDoc $ ppr alt)
+
+ flattenMultipleAltCaseExpr ::
+ BindMap
+ -- A list of bindings in effect
+ -> SignalMap -- The scrutinee
+ -> CoreBndr -- The binder to bind the scrutinee to
+ -> [CoreAlt] -- The alternatives
+ -> FlattenState ( [SignalMap], SignalMap) -- See expandExpr
+
+ flattenMultipleAltCaseExpr binds scrut b (a:a':alts) = do
+ (args, res) <- flattenSingleAltCaseExpr binds scrut b a
+ (args', res') <- flattenMultipleAltCaseExpr binds scrut b (a':alts)
+ case a of
+ (DataAlt datacon, bind_vars, expr) -> do
+ if isDontCare datacon
+ then do
+ -- Completely skip the dontcare cases
+ return (args', res')
+ else do
+ lit <- dataConToLiteral datacon
+ -- The scrutinee must be a single signal
+ let Single sig = scrut
+ -- Create a signal that contains a boolean
+ boolsigid <- genSignalId SigInternal TysWiredIn.boolTy
+ addNameHint ("s" ++ show sig ++ "_eq_" ++ lit) boolsigid
+ let expr = EqLit sig lit
+ addDef (UncondDef (Right expr) boolsigid)
+ -- Create conditional assignments of either args/res or
+ -- args'/res based on boolsigid, and return the result.
+ -- TODO: It seems this adds the name hint twice?
+ our_args <- Monad.zipWithM (mkConditionals boolsigid) args args'
+ our_res <- mkConditionals boolsigid res res'
+ return (our_args, our_res)
+ otherwise ->
+ error $ "Case patterns other than data constructors not supported in case alternative: " ++ (showSDoc $ ppr a)
+ where
+ -- Select either the first or second signal map depending on the value
+ -- of the first argument (True == first map, False == second map)
+ mkConditionals :: SignalId -> SignalMap -> SignalMap -> FlattenState SignalMap
+ mkConditionals boolsigid true false = do
+ let zipped = zipValueMaps true false
+ Traversable.mapM (mkConditional boolsigid) zipped
+
+ mkConditional :: SignalId -> (SignalId, SignalId) -> FlattenState SignalId
+ mkConditional boolsigid (true, false) = do
+ -- Create a new signal (true and false should be identically typed,
+ -- so it doesn't matter which one we copy).
+ res <- copySignal true
+ addDef (CondDef boolsigid true false res)
+ return res
+
+ flattenMultipleAltCaseExpr binds scrut b (a:alts) =
+ flattenSingleAltCaseExpr binds scrut b a
+
+flattenExpr _ expr = do
+ error $ "Unsupported expression: " ++ (showSDoc $ ppr expr)
+
+-- | Is the given data constructor a dontcare?
+isDontCare :: DataCon.DataCon -> Bool
+isDontCare datacon =
+ case Name.getOccString tyname of
+ -- TODO: Do something more robust than string matching
+ "Bit" ->
+ Name.getOccString dcname == "DontCare"
+ otherwise ->
+ False
+ where
+ tycon = DataCon.dataConTyCon datacon
+ tyname = TyCon.tyConName tycon
+ dcname = DataCon.dataConName datacon
+
+-- | Translates a dataconstructor without arguments to the corresponding
+-- literal.
+dataConToLiteral :: DataCon.DataCon -> FlattenState String
+dataConToLiteral datacon = do
+ let tycon = DataCon.dataConTyCon datacon
+ let tyname = TyCon.tyConName tycon
+ case Name.getOccString tyname of
+ -- TODO: Do something more robust than string matching
+ "Bit" -> do
+ let dcname = DataCon.dataConName datacon
+ let lit = case Name.getOccString dcname of "High" -> "'1'"; "Low" -> "'0'"; "DontCare" -> "'-'"
+ return lit
+ "Bool" -> do
+ let dcname = DataCon.dataConName datacon
+ let lit = case Name.getOccString dcname of "True" -> "true"; "False" -> "false"
+ return lit
+ otherwise ->
+ error $ "Literals of type " ++ (Name.getOccString tyname) ++ " not supported."
+
+appToHsFunction ::
+ Type.Type -- ^ The return type
+ -> Var.Var -- ^ The function to call
+ -> [CoreExpr] -- ^ The function arguments
+ -> HsFunction -- ^ The needed HsFunction
+
+appToHsFunction ty f args =
+ HsFunction hsname hsargs hsres
+ where
+ hsname = Name.getOccString f
+ hsargs = map (useAsPort . mkHsValueMap . CoreUtils.exprType) args
+ hsres = useAsPort (mkHsValueMap ty)
+
+-- | Filters non-state signals and returns the state number and signal id for
+-- state values.
+filterState ::
+ SignalId -- | The signal id to look at
+ -> HsValueUse -- | How is this signal used?
+ -> Maybe (StateId, SignalId ) -- | The state num and signal id, if this
+ -- signal was used as state
+
+filterState id (State num) =
+ Just (num, id)
+filterState _ _ = Nothing
+
+-- | Returns a list of the state number and signal id of all used-as-state
+-- signals in the given maps.
+stateList ::
+ HsUseMap
+ -> (SignalMap)
+ -> [(StateId, SignalId)]
+
+stateList uses signals =
+ Maybe.catMaybes $ Foldable.toList $ zipValueMapsWith filterState signals uses
+
+-- | Returns pairs of signals that should be mapped to state in this function.
+getOwnStates ::
+ HsFunction -- | The function to look at
+ -> FlatFunction -- | The function to look at
+ -> [(StateId, SignalInfo, SignalInfo)]
+ -- | The state signals. The first is the state number, the second the
+ -- signal to assign the current state to, the last is the signal
+ -- that holds the new state.
+
+getOwnStates hsfunc flatfunc =
+ [(old_num, old_info, new_info)
+ | (old_num, old_info) <- args_states
+ , (new_num, new_info) <- res_states
+ , old_num == new_num]
+ where
+ sigs = flat_sigs flatfunc
+ -- Translate args and res to lists of (statenum, sigid)
+ args = concat $ zipWith stateList (hsFuncArgs hsfunc) (flat_args flatfunc)
+ res = stateList (hsFuncRes hsfunc) (flat_res flatfunc)
+ -- Replace the second tuple element with the corresponding SignalInfo
+ args_states = map (Arrow.second $ signalInfo sigs) args
+ res_states = map (Arrow.second $ signalInfo sigs) res
+
+