import qualified Type
import qualified Name
import qualified Maybe
+import qualified Control.Arrow as Arrow
import qualified DataCon
import qualified CoreUtils
+import qualified Data.Traversable as Traversable
+import qualified Data.Foldable as Foldable
import Control.Applicative
import Outputable ( showSDoc, ppr )
import qualified Control.Monad.State as State
where
tycount = length $ DataCon.dataConAllTyVars dc
-genSignalUses ::
+genSignals ::
Type.Type
- -> FlattenState SignalUseMap
+ -> FlattenState SignalMap
-genSignalUses ty = do
- typeMapToUseMap tymap
- where
- -- First generate a map with the right structure containing the types
- tymap = mkHsValueMap ty
-
-typeMapToUseMap ::
- HsValueMap Type.Type
- -> FlattenState SignalUseMap
+genSignals ty =
+ -- First generate a map with the right structure containing the types, and
+ -- generate signals for each of them.
+ Traversable.mapM (\ty -> genSignalId SigInternal ty) (mkHsValueMap ty)
-typeMapToUseMap (Single ty) = do
- id <- genSignalId
- return $ Single (SignalUse id)
+-- | Marks a signal as the given SigUse, if its id is in the list of id's
+-- given.
+markSignals :: SigUse -> [SignalId] -> (SignalId, SignalInfo) -> (SignalId, SignalInfo)
+markSignals use ids (id, info) =
+ (id, info')
+ where
+ info' = if id `elem` ids then info { sigUse = use} else info
-typeMapToUseMap (Tuple tymaps) = do
- usemaps <- State.mapM typeMapToUseMap tymaps
- return $ Tuple usemaps
+markSignal :: SigUse -> SignalId -> (SignalId, SignalInfo) -> (SignalId, SignalInfo)
+markSignal use id = markSignals use [id]
-- | Flatten a haskell function
flattenFunction ::
flattenFunction _ (Rec _) = error "Recursive binders not supported"
flattenFunction hsfunc bind@(NonRec var expr) =
- FlatFunction args res apps conds
+ FlatFunction args res defs sigs
where
init_state = ([], [], 0)
- (fres, end_state) = State.runState (flattenExpr [] expr) init_state
+ (fres, end_state) = State.runState (flattenTopExpr hsfunc expr) init_state
+ (defs, sigs, _) = end_state
(args, res) = fres
- (apps, conds, _) = end_state
+flattenTopExpr ::
+ HsFunction
+ -> CoreExpr
+ -> FlattenState ([SignalMap], SignalMap)
+
+flattenTopExpr hsfunc expr = do
+ -- Flatten the expression
+ (args, res) <- flattenExpr [] expr
+
+ -- Join the signal ids and uses together
+ let zipped_args = zipWith zipValueMaps args (hsFuncArgs hsfunc)
+ let zipped_res = zipValueMaps res (hsFuncRes hsfunc)
+ -- Set the signal uses for each argument / result, possibly updating
+ -- argument or result signals.
+ args' <- mapM (Traversable.mapM $ hsUseToSigUse args_use) zipped_args
+ res' <- Traversable.mapM (hsUseToSigUse res_use) zipped_res
+ return (args', res')
+ where
+ args_use Port = SigPortIn
+ args_use (State n) = SigStateOld n
+ res_use Port = SigPortOut
+ res_use (State n) = SigStateNew n
+
+
+hsUseToSigUse ::
+ (HsValueUse -> SigUse) -- ^ A function to actually map the use value
+ -> (SignalId, HsValueUse) -- ^ The signal to look at and its use
+ -> FlattenState SignalId -- ^ The resulting signal. This is probably the
+ -- same as the input, but it could be different.
+hsUseToSigUse f (id, use) = do
+ info <- getSignalInfo id
+ id' <- case sigUse info of
+ -- Internal signals can be marked as different uses freely.
+ SigInternal -> do
+ return id
+ -- Signals that already have another use, must be duplicated before
+ -- marking. This prevents signals mapping to the same input or output
+ -- port or state variables and ports overlapping, etc.
+ otherwise -> do
+ duplicateSignal id
+ setSignalInfo id' (info { sigUse = f use})
+ return id'
+
+-- | Duplicate the given signal, assigning its value to the new signal.
+-- Returns the new signal id.
+duplicateSignal :: SignalId -> FlattenState SignalId
+duplicateSignal id = do
+ -- Find the type of the original signal
+ info <- getSignalInfo id
+ let ty = sigTy info
+ -- Generate a new signal (which is SigInternal for now, that will be
+ -- sorted out later on).
+ id' <- genSignalId SigInternal ty
+ -- Assign the old signal to the new signal
+ addDef $ UncondDef id id'
+ -- Replace the signal with the new signal
+ return id'
+
flattenExpr ::
BindMap
-> CoreExpr
- -> FlattenState ([SignalDefMap], SignalUseMap)
+ -> FlattenState ([SignalMap], SignalMap)
flattenExpr binds lam@(Lam b expr) = do
-- Find the type of the binder
let (arg_ty, _) = Type.splitFunTy (CoreUtils.exprType lam)
-- Create signal names for the binder
- defs <- genSignalUses arg_ty
+ defs <- genSignals arg_ty
let binds' = (b, Left defs):binds
(args, res) <- flattenExpr binds' expr
- return ((useMapToDefMap defs) : args, res)
+ return (defs : args, res)
flattenExpr binds (Var id) =
case bind of
-- Check and split each of the arguments
let (_, arg_ress) = unzip (zipWith checkArg args flat_args)
-- Generate signals for our result
- res <- genSignalUses ty
+ res <- genSignals ty
-- Create the function application
let app = FApp {
appFunc = func,
appArgs = arg_ress,
- appRes = useMapToDefMap res
+ appRes = res
}
- addApp app
+ addDef app
return ([], res)
-- | Check a flattened expression to see if it is valid to use as a
-- function argument. The first argument is the original expression for
-> Var.Var -- The scrutinee
-> CoreBndr -- The binder to bind the scrutinee to
-> CoreAlt -- The single alternative
- -> FlattenState ( [SignalDefMap], SignalUseMap)
+ -> FlattenState ( [SignalMap], SignalMap)
-- See expandExpr
flattenSingleAltCaseExpr binds v b alt@(DataAlt datacon, bind_vars, expr) =
if not (DataCon.isTupleCon datacon)
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
+
+
-- vim: set ts=8 sw=2 sts=2 expandtab: