+expandExpr ::
+ [(CoreBndr, SignalNameMap AST.VHDLId)]
+ -- A list of bindings in effect
+ -> CoreExpr -- The expression to expand
+ -> VHDLState (
+ [AST.SigDec], -- Needed signal declarations
+ [AST.ConcSm], -- Needed component instantations and
+ -- signal assignments.
+ [SignalNameMap AST.VHDLId], -- The signal names corresponding to
+ -- the expression's arguments
+ SignalNameMap AST.VHDLId) -- The signal names corresponding to
+ -- the expression's result.
+expandExpr binds (Lam b expr) = do
+ -- Generate a new signal to which we will expect this argument to be bound.
+ signal_name <- uniqueName ("arg-" ++ getOccString b)
+ -- TODO: This uses the bit type hardcoded
+ let (signal_id, signal_decl) = mkSignal signal_name vhdl_bit_ty
+ -- Add the binder to the list of binds
+ let binds' = (b, Signal signal_id) : binds
+ -- Expand the rest of the expression
+ (signal_decls, statements, arg_signals, res_signal) <- expandExpr binds' expr
+ -- Properly merge the results
+ return (signal_decl : signal_decls,
+ statements,
+ (Signal signal_id) : arg_signals,
+ res_signal)
+
+expandExpr binds (Var id) =
+ return ([], [], [], Signal signal_id)
+ where
+ -- Lookup the id in our binds map
+ Signal signal_id = Maybe.fromMaybe
+ (error $ "Argument " ++ getOccString id ++ "is unknown")
+ (lookup id binds)
+
+expandExpr binds app@(App _ _) = do
+ let ((Var f), args) = collectArgs app
+ if isTupleConstructor f
+ then
+ expandBuildTupleExpr binds args
+ else
+ expandApplicationExpr binds (CoreUtils.exprType app) f args
+
+expandExpr binds expr =
+ error $ "Unsupported expression: " ++ (showSDoc $ ppr $ expr)
+
+-- Expands the construction of a tuple into VHDL
+expandBuildTupleExpr ::
+ [(CoreBndr, SignalNameMap AST.VHDLId)]
+ -- A list of bindings in effect
+ -> [CoreExpr] -- A list of expressions to put in the tuple
+ -> VHDLState ( [AST.SigDec], [AST.ConcSm], [SignalNameMap AST.VHDLId], SignalNameMap AST.VHDLId)
+ -- See expandExpr
+expandBuildTupleExpr binds args =
+ error $ "Tuple construction not supported"
+
+-- Expands the application of argument to a function into VHDL
+expandApplicationExpr ::
+ [(CoreBndr, SignalNameMap AST.VHDLId)]
+ -- A list of bindings in effect
+ -> Type -- The result type of the function call
+ -> Var.Var -- The function to call
+ -> [CoreExpr] -- A list of argumetns to apply to the function
+ -> VHDLState ( [AST.SigDec], [AST.ConcSm], [SignalNameMap AST.VHDLId], SignalNameMap AST.VHDLId)
+ -- See expandExpr
+expandApplicationExpr binds ty f args = do
+ let name = getOccString f
+ -- Generate a unique name for the application
+ appname <- uniqueName ("app-" ++ name)
+ -- Lookup the hwfunction to instantiate
+ HWFunction inports outport <- getHWFunc name
+ -- Expand each of the args, so each of them is reduced to output signals
+ (arg_signal_decls, arg_statements, arg_res_signals) <- expandArgs binds args
+ -- Bind each of the input ports to the expanded arguments
+ let inmaps = concat $ zipWith createAssocElems inports arg_res_signals
+ -- Create signal names for our result
+ let res_signal = getPortNameMapForTy (appname ++ "-out") ty
+ -- Create the corresponding signal declarations
+ let signal_decls = mkSignalsFromMap res_signal
+ -- Bind each of the output ports to our output signals
+ let outmaps = mapOutputPorts outport res_signal
+ -- Instantiate the component
+ let component = AST.CSISm $ AST.CompInsSm
+ (AST.unsafeVHDLBasicId appname)
+ (AST.IUEntity (AST.NSimple (AST.unsafeVHDLBasicId name)))
+ (AST.PMapAspect (inmaps ++ outmaps))
+ -- Merge the generated declarations
+ return (
+ signal_decls ++ arg_signal_decls,
+ component : arg_statements,
+ [], -- We don't take any extra arguments; we don't support higher order functions yet
+ res_signal)
+
+-- Creates a list of AssocElems (port map lines) that maps the given signals
+-- to the given ports.
+createAssocElems ::
+ SignalNameMap AST.VHDLId -- The port names to bind to
+ -> SignalNameMap AST.VHDLId -- The signals to bind to it
+ -> [AST.AssocElem] -- The resulting port map lines
+
+createAssocElems (Signal port_id) (Signal signal_id) =
+ [(Just port_id) AST.:=>: (AST.ADName (AST.NSimple signal_id))]
+
+createAssocElems (Tuple ports) (Tuple signals) =
+ concat $ zipWith createAssocElems ports signals
+
+-- Generate a signal declaration for a signal with the given name and the
+-- given type and no value. Also returns the id of the signal.
+mkSignal :: String -> AST.TypeMark -> (AST.VHDLId, AST.SigDec)
+mkSignal name ty =
+ (id, mkSignalFromId id ty)
+ where
+ id = AST.unsafeVHDLBasicId name
+
+mkSignalFromId :: AST.VHDLId -> AST.TypeMark -> AST.SigDec
+mkSignalFromId id ty =
+ AST.SigDec id ty Nothing
+
+-- Generates signal declarations for all the signals in the given map
+mkSignalsFromMap ::
+ SignalNameMap AST.VHDLId
+ -> [AST.SigDec]
+
+mkSignalsFromMap (Signal id) =
+ -- TODO: This uses the bit type hardcoded
+ [mkSignalFromId id vhdl_bit_ty]
+
+mkSignalsFromMap (Tuple signals) =
+ concat $ map mkSignalsFromMap signals
+
+expandArgs ::
+ [(CoreBndr, SignalNameMap AST.VHDLId)] -- A list of bindings in effect
+ -> [CoreExpr] -- The arguments to expand
+ -> VHDLState ([AST.SigDec], [AST.ConcSm], [SignalNameMap AST.VHDLId])
+ -- The resulting signal declarations,
+ -- component instantiations and a
+ -- VHDLName for each of the
+ -- expressions passed in.
+expandArgs binds (e:exprs) = do
+ -- Expand the first expression
+ arg <- case e of
+ -- A simple variable reference should be in our binds map
+ Var id -> return $ let
+ -- Lookup the id in our binds map
+ Signal signalid = Maybe.fromMaybe
+ (error $ "Argument " ++ getOccString id ++ "is unknown")
+ (lookup id binds)
+ in
+ -- Create a VHDL name from the signal name
+ Signal signalid
+ -- Other expressions are unsupported
+ otherwise -> error ("Unsupported expression used as argument: " ++ (showSDoc $ ppr e))
+ -- Expand the rest
+ (sigs, comps, args) <- expandArgs binds exprs
+ -- Return all results
+ return (sigs, comps, arg:args)
+
+expandArgs _ [] = return ([], [], [])
+