X-Git-Url: https://git.stderr.nl/gitweb?a=blobdiff_plain;ds=sidebyside;f=Flatten.hs;h=fc60d6ae397dec21840cb21de54e9389fb07ba84;hb=e771c40c12c3d93a1c59b396cf862cb0ac617d94;hp=598c8c6050df46cba753bb97351aff4abf4c559a;hpb=3bd18744c55ac99fbc0fff05c74926e80be92ff9;p=matthijs%2Fmaster-project%2Fc%CE%BBash.git diff --git a/Flatten.hs b/Flatten.hs index 598c8c6..fc60d6a 100644 --- a/Flatten.hs +++ b/Flatten.hs @@ -1,149 +1,52 @@ module Flatten where import CoreSyn +import Control.Monad +import qualified Var import qualified Type import qualified Name -import qualified TyCon import qualified Maybe +import qualified Control.Arrow as Arrow +import qualified DataCon +import qualified TyCon import qualified CoreUtils +import qualified TysWiredIn +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 --- | A datatype that maps each of the single values in a haskell structure to --- a mapto. The map has the same structure as the haskell type mapped, ie --- nested tuples etc. -data HsValueMap mapto = - Tuple [HsValueMap mapto] - | Single mapto - deriving (Show, Eq) - +import HsValueMap +import TranslatorTypes +import FlattenTypes +-- Extract the arguments from a data constructor application (that is, the +-- normal args, leaving out the type args). +dataConAppArgs :: DataCon.DataCon -> [CoreExpr] -> [CoreExpr] +dataConAppArgs dc args = + drop tycount args + where + tycount = length $ DataCon.dataConAllTyVars dc --- | Creates a HsValueMap with the same structure as the given type, using the --- given function for mapping the single types. -mkHsValueMap :: - Type.Type -- ^ The type to map to a HsValueMap - -> HsValueMap Type.Type -- ^ The resulting map and state - -mkHsValueMap ty = - case Type.splitTyConApp_maybe ty of - Just (tycon, args) -> - if (TyCon.isTupleTyCon tycon) - then - Tuple (map mkHsValueMap args) - else - Single ty - Nothing -> Single ty - -data FlatFunction = FlatFunction { - args :: [SignalDefMap], - res :: SignalUseMap, - --sigs :: [SignalDef], - apps :: [App], - conds :: [CondDef] -} deriving (Show, Eq) - -type SignalUseMap = HsValueMap SignalUse -type SignalDefMap = HsValueMap SignalDef - -useMapToDefMap :: SignalUseMap -> SignalDefMap -useMapToDefMap (Single (SignalUse u)) = Single (SignalDef u) -useMapToDefMap (Tuple uses) = Tuple (map useMapToDefMap uses) - -type SignalId = Int -data SignalUse = SignalUse { - sigUseId :: SignalId -} deriving (Show, Eq) - -data SignalDef = SignalDef { - sigDefId :: SignalId -} deriving (Show, Eq) - -data App = App { - appFunc :: HsFunction, - appArgs :: [SignalUseMap], - appRes :: SignalDefMap -} deriving (Show, Eq) - -data CondDef = CondDef { - cond :: SignalUse, - high :: SignalUse, - low :: SignalUse, - condRes :: SignalDef -} deriving (Show, Eq) - --- | How is a given (single) value in a function's type (ie, argument or --- 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 - -- match input state to output state. - | HighOrder { -- ^ Use it as a high order function input - hoName :: String, -- ^ Which function is passed in? - hoArgs :: [HsUseMap] -- ^ Which arguments are already applied? This - -- ^ map should only contain Port and other - -- HighOrder values. - } - deriving (Show, Eq) - -type HsUseMap = HsValueMap HsValueUse - -data HsFunction = HsFunction { - hsFuncName :: String, - hsFuncArgs :: [HsUseMap], - hsFuncRes :: HsUseMap -} deriving (Show, Eq) - -type BindMap = [( - CoreBndr, -- ^ The bind name - Either -- ^ The bind value which is either - SignalUseMap -- ^ a signal - ( - HsValueUse, -- ^ or a HighOrder function - [SignalUse] -- ^ With these signals already applied to it - ) - )] - -type FlattenState = State.State ([App], [CondDef], SignalId) - --- | Add an application to the current FlattenState -addApp :: App -> FlattenState () -addApp a = do - (apps, conds, n) <- State.get - State.put (a:apps, conds, n) - --- | Add a conditional definition to the current FlattenState -addCondDef :: CondDef -> FlattenState () -addCondDef c = do - (apps, conds, n) <- State.get - State.put (apps, c:conds, n) - --- | Generates a new signal id, which is unique within the current flattening. -genSignalId :: FlattenState SignalId -genSignalId = do - (apps, conds, n) <- State.get - State.put (apps, conds, n+1) - return n - -genSignalUses :: +genSignals :: Type.Type - -> FlattenState SignalUseMap - -genSignalUses ty = do - typeMapToUseMap tymap + -> FlattenState SignalMap + +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) + +-- | 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 - -- First generate a map with the right structure containing the types - tymap = mkHsValueMap ty - -typeMapToUseMap :: - HsValueMap Type.Type - -> FlattenState SignalUseMap - -typeMapToUseMap (Single ty) = do - id <- genSignalId - return $ Single (SignalUse id) + info' = if id `elem` ids then info { sigUse = use} else info -typeMapToUseMap (Tuple tymaps) = do - usemaps <- mapM typeMapToUseMap tymaps - return $ Tuple usemaps +markSignal :: SigUse -> SignalId -> (SignalId, SignalInfo) -> (SignalId, SignalInfo) +markSignal use id = markSignals use [id] -- | Flatten a haskell function flattenFunction :: @@ -153,26 +56,90 @@ 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' + +-- | Creates a new internal signal with the same type as the given signal +copySignal :: SignalId -> FlattenState SignalId +copySignal 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). + genSignalId SigInternal ty + +-- | Duplicate the given signal, assigning its value to the new signal. +-- Returns the new signal id. +duplicateSignal :: SignalId -> FlattenState SignalId +duplicateSignal id = do + -- Create a new signal + id' <- copySignal id + -- Assign the old signal to the new signal + addDef $ UncondDef (Left 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 @@ -180,11 +147,226 @@ flattenExpr binds (Var id) = Right _ -> error "Higher order functions not supported." where bind = Maybe.fromMaybe - (error $ "Argument " ++ Name.getOccString id ++ "is unknown") + (error $ "Argument " ++ Name.getOccString id ++ " is unknown") (lookup id binds) +flattenExpr binds app@(App _ _) = do + -- Is this a data constructor application? + case CoreUtils.exprIsConApp_maybe app of + -- Is this a tuple construction? + Just (dc, args) -> if DataCon.isTupleCon dc + then + flattenBuildTupleExpr binds (dataConAppArgs dc args) + else + error $ "Data constructors other than tuples not supported: " ++ (showSDoc $ ppr app) + otherwise -> + -- Normal function application + let ((Var f), args) = collectArgs app in + flattenApplicationExpr binds (CoreUtils.exprType app) f args + where + flattenBuildTupleExpr binds args = do + -- Flatten each of our args + flat_args <- (State.mapM (flattenExpr binds) args) + -- Check and split each of the arguments + let (_, arg_ress) = unzip (zipWith checkArg args flat_args) + let res = Tuple arg_ress + return ([], res) + + -- | Flatten a normal application expression + flattenApplicationExpr binds ty f args = do + -- Find the function to call + let func = appToHsFunction ty f args + -- Flatten each of our args + flat_args <- (State.mapM (flattenExpr binds) args) + -- Check and split each of the arguments + let (_, arg_ress) = unzip (zipWith checkArg args flat_args) + -- Generate signals for our result + res <- genSignals ty + -- Create the function application + let app = FApp { + appFunc = func, + appArgs = arg_ress, + appRes = res + } + 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 + -- use in the error message. + checkArg arg flat = + let (args, res) = flat in + if not (null args) + then error $ "Passing lambda expression or function as a function argument not supported: " ++ (showSDoc $ ppr arg) + else flat + +flattenExpr binds l@(Let (NonRec b bexpr) expr) = do + (b_args, b_res) <- flattenExpr binds bexpr + if not (null b_args) + then + error $ "Higher order functions not supported in let expression: " ++ (showSDoc $ ppr l) + else + let binds' = (b, Left b_res) : binds in + flattenExpr binds' expr + +flattenExpr binds l@(Let (Rec _) _) = error $ "Recursive let definitions not supported: " ++ (showSDoc $ ppr l) + +flattenExpr binds expr@(Case (Var v) b _ alts) = + case alts of + [alt] -> flattenSingleAltCaseExpr binds var b alt + otherwise -> flattenMultipleAltCaseExpr binds var b alts + where + var = Maybe.fromMaybe + (error $ "Case expression uses unknown scrutinee " ++ Name.getOccString v) + (lookup v binds) + + flattenSingleAltCaseExpr :: + BindMap + -- A list of bindings in effect + -> BindValue -- The scrutinee + -> CoreBndr -- The binder to bind the scrutinee to + -> CoreAlt -- The single alternative + -> FlattenState ( [SignalMap], SignalMap) -- See expandExpr + + flattenSingleAltCaseExpr binds var b alt@(DataAlt datacon, bind_vars, expr) = + if DataCon.isTupleCon datacon + then + let + -- 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. + Left (Tuple tuple_sigs) = var + -- TODO include b in the binds list + -- Merge our existing binds with the new binds. + binds' = (zip bind_vars (map Left tuple_sigs)) ++ binds + in + -- 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 _ _ _ alt = error $ "Case patterns other than data constructors not supported in case alternative: " ++ (showSDoc $ ppr alt) + + flattenMultipleAltCaseExpr :: + BindMap + -- A list of bindings in effect + -> BindValue -- The scrutinee + -> CoreBndr -- The binder to bind the scrutinee to + -> [CoreAlt] -- The alternatives + -> FlattenState ( [SignalMap], SignalMap) -- See expandExpr + + flattenMultipleAltCaseExpr binds var b (a:a':alts) = do + (args, res) <- flattenSingleAltCaseExpr binds var b a + (args', res') <- flattenMultipleAltCaseExpr binds var b (a':alts) + case a of + (DataAlt datacon, bind_vars, expr) -> 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 + -- The scrutinee must be a single signal + let Left (Single sig) = var + let dcname = DataCon.dataConName datacon + let lit = case Name.getOccString dcname of "High" -> "'1'"; "Low" -> "'0'" + -- Create a signal that contains a boolean + boolsigid <- genSignalId SigInternal TysWiredIn.boolTy + 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. + our_args <- zipWithM (mkConditionals boolsigid) args args' + our_res <- mkConditionals boolsigid res res' + return (our_args, our_res) + otherwise -> + error $ "Type " ++ (Name.getOccString tyname) ++ " not supported in multiple alternative case expressions." + 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 var b (a:alts) = + flattenSingleAltCaseExpr binds var b a + + + flattenExpr _ _ = do return ([], Tuple []) +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 + + -- vim: set ts=8 sw=2 sts=2 expandtab: