module Flatten where
import CoreSyn
-import Control.Monad
+import qualified Control.Monad as Monad
import qualified Var
import qualified Type
import qualified Name
import qualified Maybe
import qualified Control.Arrow as Arrow
import qualified DataCon
+import qualified TyCon
+import qualified Literal
import qualified CoreUtils
+import qualified TysWiredIn
+import qualified IdInfo
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
+import qualified Control.Monad.Trans.State as State
import HsValueMap
import TranslatorTypes
import FlattenTypes
+import CoreTools
-- Extract the arguments from a data constructor application (that is, the
-- normal args, leaving out the type args).
genSignals ::
Type.Type
- -> FlattenState (SignalMap UnnamedSignal)
+ -> FlattenState SignalMap
genSignals ty =
-- First generate a map with the right structure containing the types, and
-- | Marks a signal as the given SigUse, if its id is in the list of id's
-- given.
-markSignals :: SigUse -> [UnnamedSignal] -> (UnnamedSignal, SignalInfo) -> (UnnamedSignal, SignalInfo)
+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
-markSignal :: SigUse -> UnnamedSignal -> (UnnamedSignal, SignalInfo) -> (UnnamedSignal, SignalInfo)
+markSignal :: SigUse -> SignalId -> (SignalId, SignalInfo) -> (SignalId, SignalInfo)
markSignal use id = markSignals use [id]
-- | Flatten a haskell function
flattenFunction ::
HsFunction -- ^ The function to flatten
- -> CoreBind -- ^ The function value
+ -> (CoreBndr, CoreExpr) -- ^ The function value
-> FlatFunction -- ^ The resulting flat function
-flattenFunction _ (Rec _) = error "Recursive binders not supported"
-flattenFunction hsfunc bind@(NonRec var expr) =
- FlatFunction args res apps conds sigs''''
+flattenFunction hsfunc (var, expr) =
+ FlatFunction args res defs sigs
where
- init_state = ([], [], [], 0)
- (fres, end_state) = State.runState (flattenExpr [] expr) init_state
- (apps, conds, sigs, _) = end_state
+ init_state = ([], [], 0)
+ (fres, end_state) = State.runState (flattenTopExpr hsfunc expr) init_state
+ (defs, sigs, _) = end_state
(args, res) = fres
- arg_ports = concat (map Foldable.toList args)
- res_ports = Foldable.toList res
- -- Mark args and result signals as input and output ports resp.
- sigs' = fmap (markSignals SigPortIn arg_ports) sigs
- sigs'' = fmap (markSignals SigPortOut res_ports) sigs'
- -- Mark args and result states as old and new state resp.
- args_states = concat $ zipWith stateList (hsFuncArgs hsfunc) args
- sigs''' = foldl (\s (num, id) -> map (markSignal (SigStateOld num) id) s) sigs'' args_states
- res_states = stateList (hsFuncRes hsfunc) res
- sigs'''' = foldl (\s (num, id) -> map (markSignal (SigStateNew num) id) s) sigs''' res_states
+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 ([SignalMap UnnamedSignal], (SignalMap UnnamedSignal))
+ -> 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 <- genSignals arg_ty
+ -- Add name hints to the generated signals
+ let binder_name = Name.getOccString b
+ Traversable.mapM (addNameHint binder_name) defs
let binds' = (b, Left defs):binds
(args, res) <- flattenExpr binds' expr
return (defs : args, res)
-flattenExpr binds (Var id) =
- case bind of
- Left sig_use -> return ([], sig_use)
- Right _ -> error "Higher order functions not supported."
- where
- bind = Maybe.fromMaybe
- (error $ "Argument " ++ Name.getOccString id ++ "is unknown")
- (lookup id binds)
+flattenExpr binds var@(Var id) =
+ case Var.globalIdVarDetails id of
+ IdInfo.NotGlobalId ->
+ let
+ bind = Maybe.fromMaybe
+ (error $ "Local value " ++ Name.getOccString id ++ " is unknown")
+ (lookup id binds)
+ in
+ case bind of
+ Left sig_use -> return ([], sig_use)
+ Right _ -> error "Higher order functions not supported."
+ IdInfo.DataConWorkId datacon -> do
+ if DataCon.isTupleCon datacon && (null $ DataCon.dataConAllTyVars datacon)
+ then do
+ -- Empty tuple construction
+ return ([], Tuple [])
+ else do
+ lit <- dataConToLiteral datacon
+ let ty = CoreUtils.exprType var
+ sig_id <- genSignalId SigInternal ty
+ -- Add a name hint to the signal
+ addNameHint (Name.getOccString id) sig_id
+ addDef (UncondDef (Right $ Literal lit Nothing) sig_id)
+ return ([], Single sig_id)
+ IdInfo.VanillaGlobal ->
+ -- Treat references to globals as an application with zero elements
+ flattenApplicationExpr binds (CoreUtils.exprType var) id []
+ otherwise ->
+ error $ "Ids other than local vars and dataconstructors not supported: " ++ (showSDoc $ ppr id)
flattenExpr binds app@(App _ _) = do
-- Is this a data constructor application?
otherwise ->
-- Normal function application
let ((Var f), args) = collectArgs app in
- flattenApplicationExpr binds (CoreUtils.exprType app) f args
+ let fname = Name.getOccString f in
+ if fname == "fst" || fname == "snd" then do
+ (args', Tuple [a, b]) <- flattenExpr binds (last args)
+ return (args', if fname == "fst" then a else b)
+ else if fname == "patError" then do
+ -- This is essentially don't care, since the program will error out
+ -- here. We'll just define undriven signals here.
+ let (argtys, resty) = Type.splitFunTys $ CoreUtils.exprType app
+ args <- mapM genSignals argtys
+ res <- genSignals resty
+ mapM (Traversable.mapM (addNameHint "NC")) args
+ Traversable.mapM (addNameHint "NC") res
+ return (args, res)
+ else if fname == "==" then do
+ -- Flatten the last two arguments (this skips the type arguments)
+ ([], a) <- flattenExpr binds (last $ init args)
+ ([], b) <- flattenExpr binds (last args)
+ res <- mkEqComparisons a b
+ return ([], res)
+ else if fname == "fromInteger" then do
+ let [to_ty, to_dict, val] = args
+ -- We assume this is an application of the GHC.Integer.smallInteger
+ -- function to a literal
+ let App smallint (Lit lit) = val
+ let (Literal.MachInt int) = lit
+ let ty = CoreUtils.exprType app
+ sig_id <- genSignalId SigInternal ty
+ -- TODO: fromInteger is defined for more types than just SizedWord
+ let len = sized_word_len ty
+ -- Use a to_unsigned to translate the number (a natural) to an unsiged
+ -- (array of bits)
+ let lit_str = "to_unsigned(" ++ (show int) ++ ", " ++ (show len) ++ ")"
+ -- Set the signal to our literal unconditionally, but add the type so
+ -- the literal will be typecast to the proper type.
+ addDef $ UncondDef (Right $ Literal lit_str (Just ty)) sig_id
+ return ([], Single sig_id)
+ else
+ flattenApplicationExpr binds (CoreUtils.exprType app) f args
where
+ mkEqComparisons :: SignalMap -> SignalMap -> FlattenState SignalMap
+ mkEqComparisons a b = do
+ let zipped = zipValueMaps a b
+ Traversable.mapM mkEqComparison zipped
+
+ mkEqComparison :: (SignalId, SignalId) -> FlattenState SignalId
+ mkEqComparison (a, b) = do
+ -- Generate a signal to hold our result
+ res <- genSignalId SigInternal TysWiredIn.boolTy
+ -- Add a name hint to the signal
+ addNameHint ("s" ++ show a ++ "_eq_s" ++ show b) res
+ addDef (UncondDef (Right $ Eq a b) res)
+ return res
+
flattenBuildTupleExpr binds args = do
-- Flatten each of our args
- flat_args <- (State.mapM (flattenExpr binds) args)
+ flat_args <- (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
- }
- addApp 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
+ else do
+ let binds' = (b, Left b_res) : binds
+ -- Add name hints to the generated signals
+ let binder_name = Name.getOccString b
+ Traversable.mapM (addNameHint binder_name) b_res
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) =
+flattenExpr binds expr@(Case scrut b _ alts) = do
+ -- TODO: Special casing for higher order functions
+ -- Flatten the scrutinee
+ (_, res) <- flattenExpr binds scrut
+ -- Put the scrutinee in the BindMap
+ let binds' = (b, Left res) : binds
case alts of
- [alt] -> flattenSingleAltCaseExpr binds v b alt
- otherwise -> error $ "Multiple alternative case expression not supported: " ++ (showSDoc $ ppr expr)
+ [alt] -> flattenSingleAltCaseExpr binds' res b alt
+ -- Reverse the alternatives, so the __DEFAULT alternative ends up last
+ otherwise -> flattenMultipleAltCaseExpr binds' res b (reverse alts)
where
flattenSingleAltCaseExpr ::
BindMap
-- A list of bindings in effect
- -> Var.Var -- The scrutinee
+ -> SignalMap -- The scrutinee
-> CoreBndr -- The binder to bind the scrutinee to
-> CoreAlt -- The single alternative
- -> FlattenState ( [SignalMap UnnamedSignal], SignalMap UnnamedSignal)
- -- See expandExpr
- flattenSingleAltCaseExpr binds v b alt@(DataAlt datacon, bind_vars, expr) =
- if not (DataCon.isTupleCon datacon)
- then
- error $ "Dataconstructors other than tuple constructors not supported in case pattern of alternative: " ++ (showSDoc $ ppr alt)
+ -> FlattenState ( [SignalMap], SignalMap) -- See expandExpr
+
+ 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
- let
- -- Lookup 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) = Maybe.fromMaybe
- (error $ "Case expression uses unknown scrutinee " ++ Name.getOccString v)
- (lookup v binds)
- -- 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
+ 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
+ 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
-
-flattenExpr _ _ = do
- return ([], Tuple [])
+ 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)
+
+-- | 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 <- (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
+ -- Add name hints to the generated signals
+ let resname = Name.getOccString f ++ "_res"
+ Traversable.mapM (addNameHint resname) res
+ -- 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
+
+-- | 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'"
+ 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
-- | Filters non-state signals and returns the state number and signal id for
-- state values.
filterState ::
- UnnamedSignal -- | The signal id to look at
+ SignalId -- | The signal id to look at
-> HsValueUse -- | How is this signal used?
- -> Maybe (Int, UnnamedSignal ) -- | The state num and signal id, if this
+ -> Maybe (StateId, SignalId ) -- | The state num and signal id, if this
-- signal was used as state
filterState id (State num) =
-- signals in the given maps.
stateList ::
HsUseMap
- -> (SignalMap UnnamedSignal)
- -> [(Int, UnnamedSignal)]
+ -> (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
- -> [(Int, 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: