{-|
  Copyright   :  (C) 2012-2016, University of Twente,
                     2016     , Myrtle Software Ltd,
                     2017     , Google Inc.,
                     2021-2022, QBayLogic B.V.
  License     :  BSD2 (see the file LICENSE)
  Maintainer  :  QBayLogic B.V. <devops@qbaylogic.com>

  Turn CoreHW terms into normalized CoreHW Terms
-}

{-# LANGUAGE CPP #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE QuasiQuotes #-}
{-# LANGUAGE TemplateHaskell #-}

module Clash.Normalize where

import           Control.Concurrent.Supply        (Supply)
import           Control.Exception                (throw)
import qualified Control.Lens                     as Lens
import           Control.Monad                    (when)
import           Control.Monad.State.Strict       (State)
import           Data.Default                     (def)
import           Data.Either                      (lefts,partitionEithers)
import qualified Data.IntMap                      as IntMap
import           Data.List
  (intersect, mapAccumL)
import qualified Data.Map                         as Map
import qualified Data.Maybe                       as Maybe
import qualified Data.Set                         as Set
import qualified Data.Set.Lens                    as Lens

#if MIN_VERSION_prettyprinter(1,7,0)
import           Prettyprinter                    (vcat)
#else
import           Data.Text.Prettyprint.Doc        (vcat)
#endif

#if MIN_VERSION_ghc(9,0,0)
import           GHC.Types.Basic                  (InlineSpec (..))
#else
import           BasicTypes                       (InlineSpec (..))
#endif

import           Clash.Annotations.BitRepresentation.Internal
  (CustomReprs)
import           Clash.Core.Evaluator.Types as WHNF (Evaluator)
import           Clash.Core.FreeVars
  (freeLocalIds, globalIds)
import           Clash.Core.HasFreeVars           (notElemFreeVars)
import           Clash.Core.HasType
import           Clash.Core.PartialEval as PE     (Evaluator)
import           Clash.Core.Pretty                (PrettyOptions(..), showPpr, showPpr', ppr)
import           Clash.Core.Subst
  (extendGblSubstList, mkSubst, substTm)
import           Clash.Core.Term                  (Term (..), collectArgsTicks
                                                  ,mkApps, mkTicks)
import           Clash.Core.Type                  (Type, splitCoreFunForallTy)
import           Clash.Core.TyCon (TyConMap)
import           Clash.Core.Type                  (isPolyTy)
import           Clash.Core.Var                   (Id, varName, varType)
import           Clash.Core.VarEnv
  (VarEnv, elemVarSet, eltsVarEnv, emptyInScopeSet, emptyVarEnv,
   extendVarEnv, lookupVarEnv, mapVarEnv, mapMaybeVarEnv,
   mkVarEnv, mkVarSet, notElemVarEnv, notElemVarSet, nullVarEnv, unionVarEnv)
import           Clash.Debug                      (traceIf)
import           Clash.Driver.Types
  (BindingMap, Binding(..), DebugOpts(..), ClashEnv(..))
import           Clash.Netlist.Types
  (HWMap, FilteredHWType(..))
import           Clash.Netlist.Util
  (splitNormalized)
import           Clash.Normalize.Strategy
import           Clash.Normalize.Transformations
import           Clash.Normalize.Types
import           Clash.Normalize.Util
import           Clash.Rewrite.Combinators        ((>->),(!->),repeatR,topdownR)
import           Clash.Rewrite.Types
  (RewriteEnv (..), RewriteState (..), bindings, debugOpts, extra,
   tcCache, topEntities, newInlineStrategy)
import           Clash.Rewrite.Util
  (apply, isUntranslatableType, runRewriteSession)
import           Clash.Util
import           Clash.Util.Interpolate           (i)

import           Data.Binary                      (encode)
import qualified Data.ByteString                  as BS
import qualified Data.ByteString.Lazy             as BL

import           System.IO.Unsafe                 (unsafePerformIO)
import           Clash.Rewrite.Types (RewriteStep(..))


-- | Run a NormalizeSession in a given environment
runNormalization
  :: ClashEnv
  -> Supply
  -- ^ UniqueSupply
  -> BindingMap
  -- ^ Global Binders
  -> (CustomReprs -> TyConMap -> Type ->
      State HWMap (Maybe (Either String FilteredHWType)))
  -- ^ Hardcoded Type -> HWType translator
  -> PE.Evaluator
  -- ^ Hardcoded evaluator for partial evaluation
  -> WHNF.Evaluator
  -- ^ Hardcoded evaluator for WHNF (old evaluator)
  -> VarEnv Bool
  -- ^ Map telling whether a components is part of a recursive group
  -> [Id]
  -- ^ topEntities
  -> NormalizeSession a
  -- ^ NormalizeSession to run
  -> IO a
runNormalization :: ClashEnv
-> Supply
-> BindingMap
-> (CustomReprs
    -> TyConMap
    -> Type
    -> State HWMap (Maybe (Either String FilteredHWType)))
-> Evaluator
-> Evaluator
-> VarEnv Bool
-> [Id]
-> NormalizeSession a
-> IO a
runNormalization ClashEnv
env Supply
supply BindingMap
globals CustomReprs
-> TyConMap
-> Type
-> State HWMap (Maybe (Either String FilteredHWType))
typeTrans Evaluator
peEval Evaluator
eval VarEnv Bool
rcsMap [Id]
topEnts =
  RewriteEnv
-> RewriteState NormalizeState -> NormalizeSession a -> IO a
forall extra a.
RewriteEnv -> RewriteState extra -> RewriteMonad extra a -> IO a
runRewriteSession RewriteEnv
rwEnv RewriteState NormalizeState
rwState
  where
    -- TODO The RewriteEnv should just take ClashOpts.
    rwEnv :: RewriteEnv
rwEnv     = ClashEnv
-> (CustomReprs
    -> TyConMap
    -> Type
    -> State HWMap (Maybe (Either String FilteredHWType)))
-> Evaluator
-> Evaluator
-> VarSet
-> RewriteEnv
RewriteEnv
                  ClashEnv
env
                  CustomReprs
-> TyConMap
-> Type
-> State HWMap (Maybe (Either String FilteredHWType))
typeTrans
                  Evaluator
peEval
                  Evaluator
eval
                  ([Id] -> VarSet
forall a. [Var a] -> VarSet
mkVarSet [Id]
topEnts)

    rwState :: RewriteState NormalizeState
rwState   = Word
-> HashMap Text Word
-> BindingMap
-> Supply
-> (Id, SrcSpan)
-> Int
-> PrimHeap
-> VarEnv Bool
-> NormalizeState
-> RewriteState NormalizeState
forall extra.
Word
-> HashMap Text Word
-> BindingMap
-> Supply
-> (Id, SrcSpan)
-> Int
-> PrimHeap
-> VarEnv Bool
-> extra
-> RewriteState extra
RewriteState
                  Word
0
                  HashMap Text Word
forall a. Monoid a => a
mempty       -- transformCounters Map
                  BindingMap
globals
                  Supply
supply
                  (String -> Id
forall a. HasCallStack => String -> a
error (String -> Id) -> String -> Id
forall a b. (a -> b) -> a -> b
$ $(String
curLoc) String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"Report as bug: no curFun",SrcSpan
noSrcSpan)
                  Int
0
                  (IntMap Term
forall a. IntMap a
IntMap.empty, Int
0)
                  VarEnv Bool
forall a. VarEnv a
emptyVarEnv
                  NormalizeState
normState

    normState :: NormalizeState
normState = BindingMap
-> Map (Id, Int, Either Term Type) Id
-> VarEnv Int
-> VarEnv (VarEnv Int)
-> Map Text (Set Int)
-> VarEnv Bool
-> NormalizeState
NormalizeState
                  BindingMap
forall a. VarEnv a
emptyVarEnv
                  Map (Id, Int, Either Term Type) Id
forall k a. Map k a
Map.empty
                  VarEnv Int
forall a. VarEnv a
emptyVarEnv
                  VarEnv (VarEnv Int)
forall a. VarEnv a
emptyVarEnv
                  Map Text (Set Int)
forall k a. Map k a
Map.empty
                  VarEnv Bool
rcsMap

normalize
  :: [Id]
  -> NormalizeSession BindingMap
normalize :: [Id] -> NormalizeSession BindingMap
normalize []  = BindingMap -> NormalizeSession BindingMap
forall (m :: Type -> Type) a. Monad m => a -> m a
return BindingMap
forall a. VarEnv a
emptyVarEnv
normalize [Id]
top = do
  ([[Id]]
new,[(Id, Binding Term)]
topNormalized) <- [([Id], (Id, Binding Term))] -> ([[Id]], [(Id, Binding Term)])
forall a b. [(a, b)] -> ([a], [b])
unzip ([([Id], (Id, Binding Term))] -> ([[Id]], [(Id, Binding Term)]))
-> RewriteMonad NormalizeState [([Id], (Id, Binding Term))]
-> RewriteMonad NormalizeState ([[Id]], [(Id, Binding Term)])
forall (f :: Type -> Type) a b. Functor f => (a -> b) -> f a -> f b
<$> (Id -> RewriteMonad NormalizeState ([Id], (Id, Binding Term)))
-> [Id] -> RewriteMonad NormalizeState [([Id], (Id, Binding Term))]
forall (t :: Type -> Type) (m :: Type -> Type) a b.
(Traversable t, Monad m) =>
(a -> m b) -> t a -> m (t b)
mapM Id -> RewriteMonad NormalizeState ([Id], (Id, Binding Term))
normalize' [Id]
top
  BindingMap
newNormalized <- [Id] -> NormalizeSession BindingMap
normalize ([[Id]] -> [Id]
forall (t :: Type -> Type) a. Foldable t => t [a] -> [a]
concat [[Id]]
new)
  BindingMap -> NormalizeSession BindingMap
forall (m :: Type -> Type) a. Monad m => a -> m a
return (BindingMap -> BindingMap -> BindingMap
forall a. VarEnv a -> VarEnv a -> VarEnv a
unionVarEnv ([(Id, Binding Term)] -> BindingMap
forall a b. [(Var a, b)] -> VarEnv b
mkVarEnv [(Id, Binding Term)]
topNormalized) BindingMap
newNormalized)

normalize' :: Id -> NormalizeSession ([Id], (Id, Binding Term))
normalize' :: Id -> RewriteMonad NormalizeState ([Id], (Id, Binding Term))
normalize' Id
nm = do
  Maybe (Binding Term)
exprM <- Id -> BindingMap -> Maybe (Binding Term)
forall b a. Var b -> VarEnv a -> Maybe a
lookupVarEnv Id
nm (BindingMap -> Maybe (Binding Term))
-> NormalizeSession BindingMap
-> RewriteMonad NormalizeState (Maybe (Binding Term))
forall (f :: Type -> Type) a b. Functor f => (a -> b) -> f a -> f b
<$> Getting BindingMap (RewriteState NormalizeState) BindingMap
-> NormalizeSession BindingMap
forall s (m :: Type -> Type) a.
MonadState s m =>
Getting a s a -> m a
Lens.use Getting BindingMap (RewriteState NormalizeState) BindingMap
forall extra. Lens' (RewriteState extra) BindingMap
bindings
  let nmS :: String
nmS = Name Term -> String
forall p. PrettyPrec p => p -> String
showPpr (Id -> Name Term
forall a. Var a -> Name a
varName Id
nm)
  case Maybe (Binding Term)
exprM of
    Just (Binding Id
nm' SrcSpan
sp InlineSpec
inl IsPrim
pr Term
tm Bool
r) -> do
      TyConMap
tcm <- Getting TyConMap RewriteEnv TyConMap
-> RewriteMonad NormalizeState TyConMap
forall s (m :: Type -> Type) a.
MonadReader s m =>
Getting a s a -> m a
Lens.view Getting TyConMap RewriteEnv TyConMap
Getter RewriteEnv TyConMap
tcCache
      VarSet
topEnts <- Getting VarSet RewriteEnv VarSet
-> RewriteMonad NormalizeState VarSet
forall s (m :: Type -> Type) a.
MonadReader s m =>
Getting a s a -> m a
Lens.view Getting VarSet RewriteEnv VarSet
Lens' RewriteEnv VarSet
topEntities
      let isTop :: Bool
isTop = Id
nm Id -> VarSet -> Bool
forall a. Var a -> VarSet -> Bool
`elemVarSet` VarSet
topEnts
          ty0 :: Type
ty0 = Id -> Type
forall a. HasType a => a -> Type
coreTypeOf Id
nm'
          ty1 :: Type
ty1 = if Bool
isTop then Type -> Type
tvSubstWithTyEq Type
ty0 else Type
ty0

      -- check for polymorphic types
      Bool
-> RewriteMonad NormalizeState () -> RewriteMonad NormalizeState ()
forall (f :: Type -> Type). Applicative f => Bool -> f () -> f ()
when (Type -> Bool
isPolyTy Type
ty1) (RewriteMonad NormalizeState () -> RewriteMonad NormalizeState ())
-> RewriteMonad NormalizeState () -> RewriteMonad NormalizeState ()
forall a b. (a -> b) -> a -> b
$
        let msg :: String
msg = String
$curLoc String -> String -> String
forall a. [a] -> [a] -> [a]
++ [i|
              Clash can only normalize monomorphic functions, but this is polymorphic:
              #{showPpr' def{displayUniques=False\} nm'}
              |]
            msgExtra :: Maybe String
msgExtra | Type
ty0 Type -> Type -> Bool
forall a. Eq a => a -> a -> Bool
== Type
ty1 = Maybe String
forall a. Maybe a
Nothing
                     | Bool
otherwise = String -> Maybe String
forall a. a -> Maybe a
Just (String -> Maybe String) -> String -> Maybe String
forall a b. (a -> b) -> a -> b
$ [i|
              Even after applying type equality constraints it remained polymorphic:
              #{showPpr' def{displayUniques=False\} nm'{varType=ty1\}}
                         |]
        in ClashException -> RewriteMonad NormalizeState ()
forall a e. Exception e => e -> a
throw (SrcSpan -> String -> Maybe String -> ClashException
ClashException SrcSpan
sp String
msg Maybe String
msgExtra)

      -- check for unrepresentable result type
      let ([Either TyVar Type]
args,Type
resTy) = TyConMap -> Type -> ([Either TyVar Type], Type)
splitCoreFunForallTy TyConMap
tcm Type
ty1
          isTopEnt :: Bool
isTopEnt = Id
nm Id -> VarSet -> Bool
forall a. Var a -> VarSet -> Bool
`elemVarSet` VarSet
topEnts
          isFunction :: Bool
isFunction = Bool -> Bool
not (Bool -> Bool) -> Bool -> Bool
forall a b. (a -> b) -> a -> b
$ [TyVar] -> Bool
forall (t :: Type -> Type) a. Foldable t => t a -> Bool
null ([TyVar] -> Bool) -> [TyVar] -> Bool
forall a b. (a -> b) -> a -> b
$ [Either TyVar Type] -> [TyVar]
forall a b. [Either a b] -> [a]
lefts [Either TyVar Type]
args
      Bool
resTyRep <- Bool -> Bool
not (Bool -> Bool)
-> RewriteMonad NormalizeState Bool
-> RewriteMonad NormalizeState Bool
forall (f :: Type -> Type) a b. Functor f => (a -> b) -> f a -> f b
<$> Bool -> Type -> RewriteMonad NormalizeState Bool
forall extra. Bool -> Type -> RewriteMonad extra Bool
isUntranslatableType Bool
False Type
resTy
      if Bool
resTyRep
         then do
            Binding Term
tmNorm <- Bool -> Id -> Binding Term -> NormalizeSession (Binding Term)
normalizeTopLvlBndr Bool
isTopEnt Id
nm (Id
-> SrcSpan -> InlineSpec -> IsPrim -> Term -> Bool -> Binding Term
forall a.
Id -> SrcSpan -> InlineSpec -> IsPrim -> a -> Bool -> Binding a
Binding Id
nm' SrcSpan
sp InlineSpec
inl IsPrim
pr Term
tm Bool
r)
            let usedBndrs :: [Id]
usedBndrs = Getting (Endo [Id]) Term Id -> Term -> [Id]
forall a s. Getting (Endo [a]) s a -> s -> [a]
Lens.toListOf Getting (Endo [Id]) Term Id
Fold Term Id
globalIds (Binding Term -> Term
forall a. Binding a -> a
bindingTerm Binding Term
tmNorm)
            Bool
-> String
-> RewriteMonad NormalizeState ()
-> RewriteMonad NormalizeState ()
forall a. Bool -> String -> a -> a
traceIf (Binding Term -> Bool
forall a. Binding a -> Bool
bindingRecursive Binding Term
tmNorm)
                    ([String] -> String
forall (t :: Type -> Type) a. Foldable t => t [a] -> [a]
concat [ $(String
curLoc),String
"Expr belonging to bndr: ",String
nmS ,String
" (:: "
                            , Type -> String
forall p. PrettyPrec p => p -> String
showPpr (Id -> Type
forall a. HasType a => a -> Type
coreTypeOf (Binding Term -> Id
forall a. Binding a -> Id
bindingId Binding Term
tmNorm))
                            , String
") remains recursive after normalization:\n"
                            , Term -> String
forall p. PrettyPrec p => p -> String
showPpr (Binding Term -> Term
forall a. Binding a -> a
bindingTerm Binding Term
tmNorm) ])
                    (() -> RewriteMonad NormalizeState ()
forall (m :: Type -> Type) a. Monad m => a -> m a
return ())
            VarEnv Id
prevNorm <- (Binding Term -> Id) -> BindingMap -> VarEnv Id
forall a b. (a -> b) -> VarEnv a -> VarEnv b
mapVarEnv Binding Term -> Id
forall a. Binding a -> Id
bindingId (BindingMap -> VarEnv Id)
-> NormalizeSession BindingMap
-> RewriteMonad NormalizeState (VarEnv Id)
forall (f :: Type -> Type) a b. Functor f => (a -> b) -> f a -> f b
<$> Getting BindingMap (RewriteState NormalizeState) BindingMap
-> NormalizeSession BindingMap
forall s (m :: Type -> Type) a.
MonadState s m =>
Getting a s a -> m a
Lens.use ((NormalizeState -> Const BindingMap NormalizeState)
-> RewriteState NormalizeState
-> Const BindingMap (RewriteState NormalizeState)
forall extra extra2.
Lens (RewriteState extra) (RewriteState extra2) extra extra2
extra((NormalizeState -> Const BindingMap NormalizeState)
 -> RewriteState NormalizeState
 -> Const BindingMap (RewriteState NormalizeState))
-> ((BindingMap -> Const BindingMap BindingMap)
    -> NormalizeState -> Const BindingMap NormalizeState)
-> Getting BindingMap (RewriteState NormalizeState) BindingMap
forall b c a. (b -> c) -> (a -> b) -> a -> c
.(BindingMap -> Const BindingMap BindingMap)
-> NormalizeState -> Const BindingMap NormalizeState
Lens' NormalizeState BindingMap
normalized)
            let toNormalize :: [Id]
toNormalize = (Id -> Bool) -> [Id] -> [Id]
forall a. (a -> Bool) -> [a] -> [a]
filter (Id -> VarSet -> Bool
forall a. Var a -> VarSet -> Bool
`notElemVarSet` VarSet
topEnts)
                            ([Id] -> [Id]) -> [Id] -> [Id]
forall a b. (a -> b) -> a -> b
$ (Id -> Bool) -> [Id] -> [Id]
forall a. (a -> Bool) -> [a] -> [a]
filter (Id -> VarEnv Id -> Bool
forall a b. Var a -> VarEnv b -> Bool
`notElemVarEnv` (Id -> Id -> VarEnv Id -> VarEnv Id
forall b a. Var b -> a -> VarEnv a -> VarEnv a
extendVarEnv Id
nm Id
nm VarEnv Id
prevNorm)) [Id]
usedBndrs
            ([Id], (Id, Binding Term))
-> RewriteMonad NormalizeState ([Id], (Id, Binding Term))
forall (m :: Type -> Type) a. Monad m => a -> m a
return ([Id]
toNormalize,(Id
nm,Binding Term
tmNorm))
         else
           do
            -- Throw an error for unrepresentable topEntities and functions
            Bool
-> RewriteMonad NormalizeState () -> RewriteMonad NormalizeState ()
forall (f :: Type -> Type). Applicative f => Bool -> f () -> f ()
when (Bool
isTopEnt Bool -> Bool -> Bool
|| Bool
isFunction) (RewriteMonad NormalizeState () -> RewriteMonad NormalizeState ())
-> RewriteMonad NormalizeState () -> RewriteMonad NormalizeState ()
forall a b. (a -> b) -> a -> b
$
              let msg :: String
msg = $(String
curLoc) String -> String -> String
forall a. [a] -> [a] -> [a]
++ [i|
                    This bndr has a non-representable return type and can't be normalized:
                    #{showPpr' def{displayUniques=False\} nm'}
                    |]
              in ClashException -> RewriteMonad NormalizeState ()
forall a e. Exception e => e -> a
throw (SrcSpan -> String -> Maybe String -> ClashException
ClashException SrcSpan
sp String
msg Maybe String
forall a. Maybe a
Nothing)

            -- But allow the compilation to proceed for nonrepresentable values.
            -- This can happen for example when GHC decides to create a toplevel binder
            -- for the ByteArray# inside of a Natural constant.
            -- (GHC-8.4 does this with tests/shouldwork/Numbers/Exp.hs)
            -- It will later be inlined by flattenCallTree.
            DebugOpts
opts <- Getting DebugOpts RewriteEnv DebugOpts
-> RewriteMonad NormalizeState DebugOpts
forall s (m :: Type -> Type) a.
MonadReader s m =>
Getting a s a -> m a
Lens.view Getting DebugOpts RewriteEnv DebugOpts
Getter RewriteEnv DebugOpts
debugOpts
            Bool
-> String
-> RewriteMonad NormalizeState ([Id], (Id, Binding Term))
-> RewriteMonad NormalizeState ([Id], (Id, Binding Term))
forall a. Bool -> String -> a -> a
traceIf (DebugOpts -> Bool
dbg_invariants DebugOpts
opts)
                    ([String] -> String
forall (t :: Type -> Type) a. Foldable t => t [a] -> [a]
concat [$(String
curLoc), String
"Expr belonging to bndr: ", String
nmS, String
" (:: "
                            , Type -> String
forall p. PrettyPrec p => p -> String
showPpr (Id -> Type
forall a. HasType a => a -> Type
coreTypeOf Id
nm')
                            , String
") has a non-representable return type."
                            , String
" Not normalising:\n", Term -> String
forall p. PrettyPrec p => p -> String
showPpr Term
tm] )
                    (([Id], (Id, Binding Term))
-> RewriteMonad NormalizeState ([Id], (Id, Binding Term))
forall (m :: Type -> Type) a. Monad m => a -> m a
return ([],(Id
nm,(Id
-> SrcSpan -> InlineSpec -> IsPrim -> Term -> Bool -> Binding Term
forall a.
Id -> SrcSpan -> InlineSpec -> IsPrim -> a -> Bool -> Binding a
Binding Id
nm' SrcSpan
sp InlineSpec
inl IsPrim
pr Term
tm Bool
r))))


    Maybe (Binding Term)
Nothing -> String -> RewriteMonad NormalizeState ([Id], (Id, Binding Term))
forall a. HasCallStack => String -> a
error (String -> RewriteMonad NormalizeState ([Id], (Id, Binding Term)))
-> String -> RewriteMonad NormalizeState ([Id], (Id, Binding Term))
forall a b. (a -> b) -> a -> b
$ $(String
curLoc) String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"Expr belonging to bndr: " String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
nmS String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
" not found"

-- | Check whether the normalized bindings are non-recursive. Errors when one
-- of the components is recursive.
checkNonRecursive
  :: BindingMap
  -- ^ List of normalized binders
  -> BindingMap
checkNonRecursive :: BindingMap -> BindingMap
checkNonRecursive BindingMap
norm = case (Binding Term -> Maybe (Id, Term))
-> BindingMap -> VarEnv (Id, Term)
forall a b. (a -> Maybe b) -> VarEnv a -> VarEnv b
mapMaybeVarEnv Binding Term -> Maybe (Id, Term)
forall b. Binding b -> Maybe (Id, b)
go BindingMap
norm of
  VarEnv (Id, Term)
rcs | VarEnv (Id, Term) -> Bool
forall a. VarEnv a -> Bool
nullVarEnv VarEnv (Id, Term)
rcs  -> BindingMap
norm
  VarEnv (Id, Term)
rcs -> String -> BindingMap
forall a. HasCallStack => String -> a
error (String -> BindingMap) -> String -> BindingMap
forall a b. (a -> b) -> a -> b
$ $(String
curLoc) String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"Callgraph after normalization contains following recursive components: "
                   String -> String -> String
forall a. [a] -> [a] -> [a]
++ Doc ClashAnnotation -> String
forall a. Show a => a -> String
show ([Doc ClashAnnotation] -> Doc ClashAnnotation
forall ann. [Doc ann] -> Doc ann
vcat [ Id -> Doc ClashAnnotation
forall p. PrettyPrec p => p -> Doc ClashAnnotation
ppr Id
a Doc ClashAnnotation -> Doc ClashAnnotation -> Doc ClashAnnotation
forall a. Semigroup a => a -> a -> a
<> Term -> Doc ClashAnnotation
forall p. PrettyPrec p => p -> Doc ClashAnnotation
ppr Term
b
                                 | (Id
a,Term
b) <- VarEnv (Id, Term) -> [(Id, Term)]
forall a. VarEnv a -> [a]
eltsVarEnv VarEnv (Id, Term)
rcs
                                 ])
 where
  go :: Binding b -> Maybe (Id, b)
go (Binding Id
nm SrcSpan
_ InlineSpec
_ IsPrim
_ b
tm Bool
r) =
    if Bool
r then (Id, b) -> Maybe (Id, b)
forall a. a -> Maybe a
Just (Id
nm,b
tm) else Maybe (Id, b)
forall a. Maybe a
Nothing

-- | Perform general \"clean up\" of the normalized (non-recursive) function
-- hierarchy. This includes:
--
--   * Inlining functions that simply \"wrap\" another function
cleanupGraph
  :: Id
  -> BindingMap
  -> NormalizeSession BindingMap
cleanupGraph :: Id -> BindingMap -> NormalizeSession BindingMap
cleanupGraph Id
topEntity BindingMap
norm
  | Just CallTree
ct <- [Id] -> BindingMap -> Id -> Maybe CallTree
mkCallTree [] BindingMap
norm Id
topEntity
  = do CallTree
ctFlat <- CallTree -> NormalizeSession CallTree
flattenCallTree CallTree
ct
       BindingMap -> NormalizeSession BindingMap
forall (m :: Type -> Type) a. Monad m => a -> m a
return ([(Id, Binding Term)] -> BindingMap
forall a b. [(Var a, b)] -> VarEnv b
mkVarEnv ([(Id, Binding Term)] -> BindingMap)
-> [(Id, Binding Term)] -> BindingMap
forall a b. (a -> b) -> a -> b
$ ([Id], [(Id, Binding Term)]) -> [(Id, Binding Term)]
forall a b. (a, b) -> b
snd (([Id], [(Id, Binding Term)]) -> [(Id, Binding Term)])
-> ([Id], [(Id, Binding Term)]) -> [(Id, Binding Term)]
forall a b. (a -> b) -> a -> b
$ [Id] -> CallTree -> ([Id], [(Id, Binding Term)])
callTreeToList [] CallTree
ctFlat)
cleanupGraph Id
_ BindingMap
norm = BindingMap -> NormalizeSession BindingMap
forall (m :: Type -> Type) a. Monad m => a -> m a
return BindingMap
norm

-- | A tree of identifiers and their bindings, with branches containing
-- additional bindings which are used. See "Clash.Driver.Types.Binding".
--
data CallTree
  = CLeaf   (Id, Binding Term)
  | CBranch (Id, Binding Term) [CallTree]

mkCallTree
  :: [Id]
  -- ^ Visited
  -> BindingMap
  -- ^ Global binders
  -> Id
  -- ^ Root of the call graph
  -> Maybe CallTree
mkCallTree :: [Id] -> BindingMap -> Id -> Maybe CallTree
mkCallTree [Id]
visited BindingMap
bindingMap Id
root
  | Just Binding Term
rootTm <- Id -> BindingMap -> Maybe (Binding Term)
forall b a. Var b -> VarEnv a -> Maybe a
lookupVarEnv Id
root BindingMap
bindingMap
  = let used :: [Id]
used   = Set Id -> [Id]
forall a. Set a -> [a]
Set.toList (Set Id -> [Id]) -> Set Id -> [Id]
forall a b. (a -> b) -> a -> b
$ Getting (Set Id) Term Id -> Term -> Set Id
forall a s. Getting (Set a) s a -> s -> Set a
Lens.setOf Getting (Set Id) Term Id
Fold Term Id
globalIds (Term -> Set Id) -> Term -> Set Id
forall a b. (a -> b) -> a -> b
$ (Binding Term -> Term
forall a. Binding a -> a
bindingTerm Binding Term
rootTm)
        other :: [CallTree]
other  = (Id -> Maybe CallTree) -> [Id] -> [CallTree]
forall a b. (a -> Maybe b) -> [a] -> [b]
Maybe.mapMaybe ([Id] -> BindingMap -> Id -> Maybe CallTree
mkCallTree (Id
rootId -> [Id] -> [Id]
forall a. a -> [a] -> [a]
:[Id]
visited) BindingMap
bindingMap) ((Id -> Bool) -> [Id] -> [Id]
forall a. (a -> Bool) -> [a] -> [a]
filter (Id -> [Id] -> Bool
forall (t :: Type -> Type) a.
(Foldable t, Eq a) =>
a -> t a -> Bool
`notElem` [Id]
visited) [Id]
used)
    in  case [Id]
used of
          [] -> CallTree -> Maybe CallTree
forall a. a -> Maybe a
Just ((Id, Binding Term) -> CallTree
CLeaf   (Id
root,Binding Term
rootTm))
          [Id]
_  -> CallTree -> Maybe CallTree
forall a. a -> Maybe a
Just ((Id, Binding Term) -> [CallTree] -> CallTree
CBranch (Id
root,Binding Term
rootTm) [CallTree]
other)
mkCallTree [Id]
_ BindingMap
_ Id
_ = Maybe CallTree
forall a. Maybe a
Nothing

stripArgs
  :: [Id]
  -> [Id]
  -> [Either Term Type]
  -> Maybe [Either Term Type]
stripArgs :: [Id] -> [Id] -> [Either Term Type] -> Maybe [Either Term Type]
stripArgs [Id]
_      (Id
_:[Id]
_) []   = Maybe [Either Term Type]
forall a. Maybe a
Nothing
stripArgs [Id]
allIds []    [Either Term Type]
args = if (Either Term Type -> Bool) -> [Either Term Type] -> Bool
forall (t :: Type -> Type) a.
Foldable t =>
(a -> Bool) -> t a -> Bool
any Either Term Type -> Bool
forall b. Either Term b -> Bool
mentionsId [Either Term Type]
args
                                then Maybe [Either Term Type]
forall a. Maybe a
Nothing
                                else [Either Term Type] -> Maybe [Either Term Type]
forall a. a -> Maybe a
Just [Either Term Type]
args
  where
    mentionsId :: Either Term b -> Bool
mentionsId Either Term b
t = Bool -> Bool
not (Bool -> Bool) -> Bool -> Bool
forall a b. (a -> b) -> a -> b
$ [Id] -> Bool
forall (t :: Type -> Type) a. Foldable t => t a -> Bool
null ((Term -> [Id]) -> (b -> [Id]) -> Either Term b -> [Id]
forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (Getting (Endo [Id]) Term Id -> Term -> [Id]
forall a s. Getting (Endo [a]) s a -> s -> [a]
Lens.toListOf Getting (Endo [Id]) Term Id
Fold Term Id
freeLocalIds) ([Id] -> b -> [Id]
forall a b. a -> b -> a
const []) Either Term b
t
                              [Id] -> [Id] -> [Id]
forall a. Eq a => [a] -> [a] -> [a]
`intersect`
                              [Id]
allIds)

stripArgs [Id]
allIds (Id
id_:[Id]
ids) (Left (Var Id
nm):[Either Term Type]
args)
      | Id
id_ Id -> Id -> Bool
forall a. Eq a => a -> a -> Bool
== Id
nm = [Id] -> [Id] -> [Either Term Type] -> Maybe [Either Term Type]
stripArgs [Id]
allIds [Id]
ids [Either Term Type]
args
      | Bool
otherwise = Maybe [Either Term Type]
forall a. Maybe a
Nothing
stripArgs [Id]
_ [Id]
_ [Either Term Type]
_ = Maybe [Either Term Type]
forall a. Maybe a
Nothing

flattenNode
  :: CallTree
  -> NormalizeSession (Either CallTree ((Id,Term),[CallTree]))
flattenNode :: CallTree
-> NormalizeSession (Either CallTree ((Id, Term), [CallTree]))
flattenNode c :: CallTree
c@(CLeaf (Id
_,(Binding Id
_ SrcSpan
_ InlineSpec
NoInline IsPrim
_ Term
_ Bool
_))) = Either CallTree ((Id, Term), [CallTree])
-> NormalizeSession (Either CallTree ((Id, Term), [CallTree]))
forall (m :: Type -> Type) a. Monad m => a -> m a
return (CallTree -> Either CallTree ((Id, Term), [CallTree])
forall a b. a -> Either a b
Left CallTree
c)
flattenNode c :: CallTree
c@(CLeaf (Id
nm,(Binding Id
_ SrcSpan
_ InlineSpec
_ IsPrim
_ Term
e Bool
_))) = do
  Bool
isTopEntity <- Id -> VarSet -> Bool
forall a. Var a -> VarSet -> Bool
elemVarSet Id
nm (VarSet -> Bool)
-> RewriteMonad NormalizeState VarSet
-> RewriteMonad NormalizeState Bool
forall (f :: Type -> Type) a b. Functor f => (a -> b) -> f a -> f b
<$> Getting VarSet RewriteEnv VarSet
-> RewriteMonad NormalizeState VarSet
forall s (m :: Type -> Type) a.
MonadReader s m =>
Getting a s a -> m a
Lens.view Getting VarSet RewriteEnv VarSet
Lens' RewriteEnv VarSet
topEntities
  if Bool
isTopEntity then Either CallTree ((Id, Term), [CallTree])
-> NormalizeSession (Either CallTree ((Id, Term), [CallTree]))
forall (m :: Type -> Type) a. Monad m => a -> m a
return (CallTree -> Either CallTree ((Id, Term), [CallTree])
forall a b. a -> Either a b
Left CallTree
c) else do
    TyConMap
tcm  <- Getting TyConMap RewriteEnv TyConMap
-> RewriteMonad NormalizeState TyConMap
forall s (m :: Type -> Type) a.
MonadReader s m =>
Getting a s a -> m a
Lens.view Getting TyConMap RewriteEnv TyConMap
Getter RewriteEnv TyConMap
tcCache
    let norm :: Either String ([Id], [(Id, Term)], Id)
norm = TyConMap -> Term -> Either String ([Id], [(Id, Term)], Id)
splitNormalized TyConMap
tcm Term
e
    case Either String ([Id], [(Id, Term)], Id)
norm of
      Right ([Id]
ids,[(Id
bId,Term
bExpr)],Id
_) -> do
        let (Term
fun,[Either Term Type]
args,[TickInfo]
ticks) = Term -> (Term, [Either Term Type], [TickInfo])
collectArgsTicks Term
bExpr
        case [Id] -> [Id] -> [Either Term Type] -> Maybe [Either Term Type]
stripArgs [Id]
ids ([Id] -> [Id]
forall a. [a] -> [a]
reverse [Id]
ids) ([Either Term Type] -> [Either Term Type]
forall a. [a] -> [a]
reverse [Either Term Type]
args) of
          Just [Either Term Type]
remainder | Id
bId Id -> Term -> Bool
forall a. HasFreeVars a => Var a -> a -> Bool
`notElemFreeVars` Term
bExpr ->
               Either CallTree ((Id, Term), [CallTree])
-> NormalizeSession (Either CallTree ((Id, Term), [CallTree]))
forall (m :: Type -> Type) a. Monad m => a -> m a
return (((Id, Term), [CallTree])
-> Either CallTree ((Id, Term), [CallTree])
forall a b. b -> Either a b
Right ((Id
nm,Term -> [Either Term Type] -> Term
mkApps (Term -> [TickInfo] -> Term
mkTicks Term
fun [TickInfo]
ticks) ([Either Term Type] -> [Either Term Type]
forall a. [a] -> [a]
reverse [Either Term Type]
remainder)),[]))
          Maybe [Either Term Type]
_ -> Either CallTree ((Id, Term), [CallTree])
-> NormalizeSession (Either CallTree ((Id, Term), [CallTree]))
forall (m :: Type -> Type) a. Monad m => a -> m a
return (((Id, Term), [CallTree])
-> Either CallTree ((Id, Term), [CallTree])
forall a b. b -> Either a b
Right ((Id
nm,Term
e),[]))
      Either String ([Id], [(Id, Term)], Id)
_ -> Either CallTree ((Id, Term), [CallTree])
-> NormalizeSession (Either CallTree ((Id, Term), [CallTree]))
forall (m :: Type -> Type) a. Monad m => a -> m a
return (((Id, Term), [CallTree])
-> Either CallTree ((Id, Term), [CallTree])
forall a b. b -> Either a b
Right ((Id
nm,Term
e),[]))
flattenNode b :: CallTree
b@(CBranch (Id
_,(Binding Id
_ SrcSpan
_ InlineSpec
NoInline IsPrim
_ Term
_ Bool
_)) [CallTree]
_) =
  Either CallTree ((Id, Term), [CallTree])
-> NormalizeSession (Either CallTree ((Id, Term), [CallTree]))
forall (m :: Type -> Type) a. Monad m => a -> m a
return (CallTree -> Either CallTree ((Id, Term), [CallTree])
forall a b. a -> Either a b
Left CallTree
b)
flattenNode b :: CallTree
b@(CBranch (Id
nm,(Binding Id
_ SrcSpan
_ InlineSpec
_ IsPrim
_ Term
e Bool
_)) [CallTree]
us) = do
  Bool
isTopEntity <- Id -> VarSet -> Bool
forall a. Var a -> VarSet -> Bool
elemVarSet Id
nm (VarSet -> Bool)
-> RewriteMonad NormalizeState VarSet
-> RewriteMonad NormalizeState Bool
forall (f :: Type -> Type) a b. Functor f => (a -> b) -> f a -> f b
<$> Getting VarSet RewriteEnv VarSet
-> RewriteMonad NormalizeState VarSet
forall s (m :: Type -> Type) a.
MonadReader s m =>
Getting a s a -> m a
Lens.view Getting VarSet RewriteEnv VarSet
Lens' RewriteEnv VarSet
topEntities
  if Bool
isTopEntity then Either CallTree ((Id, Term), [CallTree])
-> NormalizeSession (Either CallTree ((Id, Term), [CallTree]))
forall (m :: Type -> Type) a. Monad m => a -> m a
return (CallTree -> Either CallTree ((Id, Term), [CallTree])
forall a b. a -> Either a b
Left CallTree
b) else do
    TyConMap
tcm  <- Getting TyConMap RewriteEnv TyConMap
-> RewriteMonad NormalizeState TyConMap
forall s (m :: Type -> Type) a.
MonadReader s m =>
Getting a s a -> m a
Lens.view Getting TyConMap RewriteEnv TyConMap
Getter RewriteEnv TyConMap
tcCache
    let norm :: Either String ([Id], [(Id, Term)], Id)
norm = TyConMap -> Term -> Either String ([Id], [(Id, Term)], Id)
splitNormalized TyConMap
tcm Term
e
    case Either String ([Id], [(Id, Term)], Id)
norm of
      Right ([Id]
ids,[(Id
bId,Term
bExpr)],Id
_) -> do
        let (Term
fun,[Either Term Type]
args,[TickInfo]
ticks) = Term -> (Term, [Either Term Type], [TickInfo])
collectArgsTicks Term
bExpr
        case [Id] -> [Id] -> [Either Term Type] -> Maybe [Either Term Type]
stripArgs [Id]
ids ([Id] -> [Id]
forall a. [a] -> [a]
reverse [Id]
ids) ([Either Term Type] -> [Either Term Type]
forall a. [a] -> [a]
reverse [Either Term Type]
args) of
          Just [Either Term Type]
remainder | Id
bId Id -> Term -> Bool
forall a. HasFreeVars a => Var a -> a -> Bool
`notElemFreeVars` Term
bExpr ->
               Either CallTree ((Id, Term), [CallTree])
-> NormalizeSession (Either CallTree ((Id, Term), [CallTree]))
forall (m :: Type -> Type) a. Monad m => a -> m a
return (((Id, Term), [CallTree])
-> Either CallTree ((Id, Term), [CallTree])
forall a b. b -> Either a b
Right ((Id
nm,Term -> [Either Term Type] -> Term
mkApps (Term -> [TickInfo] -> Term
mkTicks Term
fun [TickInfo]
ticks) ([Either Term Type] -> [Either Term Type]
forall a. [a] -> [a]
reverse [Either Term Type]
remainder)),[CallTree]
us))
          Maybe [Either Term Type]
_ -> Either CallTree ((Id, Term), [CallTree])
-> NormalizeSession (Either CallTree ((Id, Term), [CallTree]))
forall (m :: Type -> Type) a. Monad m => a -> m a
return (((Id, Term), [CallTree])
-> Either CallTree ((Id, Term), [CallTree])
forall a b. b -> Either a b
Right ((Id
nm,Term
e),[CallTree]
us))
      Either String ([Id], [(Id, Term)], Id)
_ -> do
        Bool
newInlineStrat <- Getting Bool RewriteEnv Bool -> RewriteMonad NormalizeState Bool
forall s (m :: Type -> Type) a.
MonadReader s m =>
Getting a s a -> m a
Lens.view Getting Bool RewriteEnv Bool
Getter RewriteEnv Bool
newInlineStrategy
        if Bool
newInlineStrat Bool -> Bool -> Bool
|| Term -> Bool
isCheapFunction Term
e
           then Either CallTree ((Id, Term), [CallTree])
-> NormalizeSession (Either CallTree ((Id, Term), [CallTree]))
forall (m :: Type -> Type) a. Monad m => a -> m a
return (((Id, Term), [CallTree])
-> Either CallTree ((Id, Term), [CallTree])
forall a b. b -> Either a b
Right ((Id
nm,Term
e),[CallTree]
us))
           else Either CallTree ((Id, Term), [CallTree])
-> NormalizeSession (Either CallTree ((Id, Term), [CallTree]))
forall (m :: Type -> Type) a. Monad m => a -> m a
return (CallTree -> Either CallTree ((Id, Term), [CallTree])
forall a b. a -> Either a b
Left CallTree
b)

flattenCallTree
  :: CallTree
  -> NormalizeSession CallTree
flattenCallTree :: CallTree -> NormalizeSession CallTree
flattenCallTree c :: CallTree
c@(CLeaf (Id, Binding Term)
_) = CallTree -> NormalizeSession CallTree
forall (m :: Type -> Type) a. Monad m => a -> m a
return CallTree
c
flattenCallTree (CBranch (Id
nm,(Binding Id
nm' SrcSpan
sp InlineSpec
inl IsPrim
pr Term
tm Bool
r)) [CallTree]
used) = do
  [CallTree]
flattenedUsed   <- (CallTree -> NormalizeSession CallTree)
-> [CallTree] -> RewriteMonad NormalizeState [CallTree]
forall (t :: Type -> Type) (m :: Type -> Type) a b.
(Traversable t, Monad m) =>
(a -> m b) -> t a -> m (t b)
mapM CallTree -> NormalizeSession CallTree
flattenCallTree [CallTree]
used
  ([CallTree]
newUsed,[((Id, Term), [CallTree])]
il_ct) <- [Either CallTree ((Id, Term), [CallTree])]
-> ([CallTree], [((Id, Term), [CallTree])])
forall a b. [Either a b] -> ([a], [b])
partitionEithers ([Either CallTree ((Id, Term), [CallTree])]
 -> ([CallTree], [((Id, Term), [CallTree])]))
-> RewriteMonad
     NormalizeState [Either CallTree ((Id, Term), [CallTree])]
-> RewriteMonad
     NormalizeState ([CallTree], [((Id, Term), [CallTree])])
forall (f :: Type -> Type) a b. Functor f => (a -> b) -> f a -> f b
<$> (CallTree
 -> NormalizeSession (Either CallTree ((Id, Term), [CallTree])))
-> [CallTree]
-> RewriteMonad
     NormalizeState [Either CallTree ((Id, Term), [CallTree])]
forall (t :: Type -> Type) (m :: Type -> Type) a b.
(Traversable t, Monad m) =>
(a -> m b) -> t a -> m (t b)
mapM CallTree
-> NormalizeSession (Either CallTree ((Id, Term), [CallTree]))
flattenNode [CallTree]
flattenedUsed
  let ([(Id, Term)]
toInline,[[CallTree]]
il_used) = [((Id, Term), [CallTree])] -> ([(Id, Term)], [[CallTree]])
forall a b. [(a, b)] -> ([a], [b])
unzip [((Id, Term), [CallTree])]
il_ct
      subst :: Subst
subst = Subst -> [(Id, Term)] -> Subst
extendGblSubstList (InScopeSet -> Subst
mkSubst InScopeSet
emptyInScopeSet) [(Id, Term)]
toInline
  Term
newExpr <- case [(Id, Term)]
toInline of
    [] -> Term -> RewriteMonad NormalizeState Term
forall (m :: Type -> Type) a. Monad m => a -> m a
return Term
tm
    [(Id, Term)]
_  -> do
      let tm1 :: Term
tm1 = HasCallStack => Doc () -> Subst -> Term -> Term
Doc () -> Subst -> Term -> Term
substTm Doc ()
"flattenCallTree.flattenExpr" Subst
subst Term
tm

      -- NB: When -fclash-debug-history is on, emit binary data holding the recorded rewrite steps
      DebugOpts
opts <- Getting DebugOpts RewriteEnv DebugOpts
-> RewriteMonad NormalizeState DebugOpts
forall s (m :: Type -> Type) a.
MonadReader s m =>
Getting a s a -> m a
Lens.view Getting DebugOpts RewriteEnv DebugOpts
Getter RewriteEnv DebugOpts
debugOpts
      let rewriteHistFile :: Maybe String
rewriteHistFile = DebugOpts -> Maybe String
dbg_historyFile DebugOpts
opts
      Bool
-> RewriteMonad NormalizeState () -> RewriteMonad NormalizeState ()
forall (f :: Type -> Type). Applicative f => Bool -> f () -> f ()
when (Maybe String -> Bool
forall a. Maybe a -> Bool
Maybe.isJust Maybe String
rewriteHistFile) (RewriteMonad NormalizeState () -> RewriteMonad NormalizeState ())
-> RewriteMonad NormalizeState () -> RewriteMonad NormalizeState ()
forall a b. (a -> b) -> a -> b
$
        let !()
_ = IO () -> ()
forall a. IO a -> a
unsafePerformIO
             (IO () -> ()) -> IO () -> ()
forall a b. (a -> b) -> a -> b
$ String -> ByteString -> IO ()
BS.appendFile (Maybe String -> String
forall a. HasCallStack => Maybe a -> a
Maybe.fromJust Maybe String
rewriteHistFile)
             (ByteString -> IO ()) -> ByteString -> IO ()
forall a b. (a -> b) -> a -> b
$ ByteString -> ByteString
BL.toStrict
             (ByteString -> ByteString) -> ByteString -> ByteString
forall a b. (a -> b) -> a -> b
$ RewriteStep -> ByteString
forall a. Binary a => a -> ByteString
encode RewriteStep :: Context -> String -> String -> Term -> Term -> RewriteStep
RewriteStep
                 { t_ctx :: Context
t_ctx    = []
                 , t_name :: String
t_name   = String
"INLINE"
                 , t_bndrS :: String
t_bndrS  = Name Term -> String
forall p. PrettyPrec p => p -> String
showPpr (Id -> Name Term
forall a. Var a -> Name a
varName Id
nm')
                 , t_before :: Term
t_before = Term
tm
                 , t_after :: Term
t_after  = Term
tm1
                 }
        in () -> RewriteMonad NormalizeState ()
forall (f :: Type -> Type) a. Applicative f => a -> f a
pure ()
      (String, NormRewrite)
-> (String, Term)
-> (Id, SrcSpan)
-> RewriteMonad NormalizeState Term
rewriteExpr (String
"flattenExpr",NormRewrite
flatten) (Id -> String
forall p. PrettyPrec p => p -> String
showPpr Id
nm, Term
tm1) (Id
nm', SrcSpan
sp)
  let allUsed :: [CallTree]
allUsed = [CallTree]
newUsed [CallTree] -> [CallTree] -> [CallTree]
forall a. [a] -> [a] -> [a]
++ [[CallTree]] -> [CallTree]
forall (t :: Type -> Type) a. Foldable t => t [a] -> [a]
concat [[CallTree]]
il_used
  -- inline all components when the resulting expression after flattening
  -- is still considered "cheap". This happens often at the topEntity which
  -- wraps another functions and has some selectors and data-constructors.
  if InlineSpec
inl InlineSpec -> InlineSpec -> Bool
forall a. Eq a => a -> a -> Bool
/= InlineSpec
NoInline Bool -> Bool -> Bool
&& Term -> Bool
isCheapFunction Term
newExpr
     then do
        let ([Maybe (Id, Term)]
toInline',[[CallTree]]
allUsed') = [(Maybe (Id, Term), [CallTree])]
-> ([Maybe (Id, Term)], [[CallTree]])
forall a b. [(a, b)] -> ([a], [b])
unzip ((CallTree -> (Maybe (Id, Term), [CallTree]))
-> [CallTree] -> [(Maybe (Id, Term), [CallTree])]
forall a b. (a -> b) -> [a] -> [b]
map CallTree -> (Maybe (Id, Term), [CallTree])
goCheap [CallTree]
allUsed)
            subst' :: Subst
subst' = Subst -> [(Id, Term)] -> Subst
extendGblSubstList (InScopeSet -> Subst
mkSubst InScopeSet
emptyInScopeSet)
                                        ([Maybe (Id, Term)] -> [(Id, Term)]
forall a. [Maybe a] -> [a]
Maybe.catMaybes [Maybe (Id, Term)]
toInline')
        let tm1 :: Term
tm1 = HasCallStack => Doc () -> Subst -> Term -> Term
Doc () -> Subst -> Term -> Term
substTm Doc ()
"flattenCallTree.flattenCheap" Subst
subst' Term
newExpr
        Term
newExpr' <- (String, NormRewrite)
-> (String, Term)
-> (Id, SrcSpan)
-> RewriteMonad NormalizeState Term
rewriteExpr (String
"flattenCheap",NormRewrite
flatten) (Id -> String
forall p. PrettyPrec p => p -> String
showPpr Id
nm, Term
tm1) (Id
nm', SrcSpan
sp)
        CallTree -> NormalizeSession CallTree
forall (m :: Type -> Type) a. Monad m => a -> m a
return ((Id, Binding Term) -> [CallTree] -> CallTree
CBranch (Id
nm,(Id
-> SrcSpan -> InlineSpec -> IsPrim -> Term -> Bool -> Binding Term
forall a.
Id -> SrcSpan -> InlineSpec -> IsPrim -> a -> Bool -> Binding a
Binding Id
nm' SrcSpan
sp InlineSpec
inl IsPrim
pr Term
newExpr' Bool
r)) ([[CallTree]] -> [CallTree]
forall (t :: Type -> Type) a. Foldable t => t [a] -> [a]
concat [[CallTree]]
allUsed'))
     else CallTree -> NormalizeSession CallTree
forall (m :: Type -> Type) a. Monad m => a -> m a
return ((Id, Binding Term) -> [CallTree] -> CallTree
CBranch (Id
nm,(Id
-> SrcSpan -> InlineSpec -> IsPrim -> Term -> Bool -> Binding Term
forall a.
Id -> SrcSpan -> InlineSpec -> IsPrim -> a -> Bool -> Binding a
Binding Id
nm' SrcSpan
sp InlineSpec
inl IsPrim
pr Term
newExpr Bool
r)) [CallTree]
allUsed)
  where
    flatten :: NormRewrite
flatten =
      NormRewrite -> NormRewrite
forall m. Rewrite m -> Rewrite m
repeatR (NormRewrite -> NormRewrite
forall m. Rewrite m -> Rewrite m
topdownR (String -> NormRewrite -> NormRewrite
forall extra. String -> Rewrite extra -> Rewrite extra
apply String
"appProp" HasCallStack => NormRewrite
NormRewrite
appProp NormRewrite -> NormRewrite -> NormRewrite
forall (m :: Type -> Type).
Monad m =>
Transform m -> Transform m -> Transform m
>->
                 String -> NormRewrite -> NormRewrite
forall extra. String -> Rewrite extra -> Rewrite extra
apply String
"bindConstantVar" HasCallStack => NormRewrite
NormRewrite
bindConstantVar NormRewrite -> NormRewrite -> NormRewrite
forall (m :: Type -> Type).
Monad m =>
Transform m -> Transform m -> Transform m
>->
                 String -> NormRewrite -> NormRewrite
forall extra. String -> Rewrite extra -> Rewrite extra
apply String
"caseCon" HasCallStack => NormRewrite
NormRewrite
caseCon NormRewrite -> NormRewrite -> NormRewrite
forall (m :: Type -> Type).
Monad m =>
Transform m -> Transform m -> Transform m
>->
                 (String -> NormRewrite -> NormRewrite
forall extra. String -> Rewrite extra -> Rewrite extra
apply String
"reduceConst" HasCallStack => NormRewrite
NormRewrite
reduceConst NormRewrite -> NormRewrite -> NormRewrite
forall m. Rewrite m -> Rewrite m -> Rewrite m
!-> String -> NormRewrite -> NormRewrite
forall extra. String -> Rewrite extra -> Rewrite extra
apply String
"deadcode" HasCallStack => NormRewrite
NormRewrite
deadCode) NormRewrite -> NormRewrite -> NormRewrite
forall (m :: Type -> Type).
Monad m =>
Transform m -> Transform m -> Transform m
>->
                 String -> NormRewrite -> NormRewrite
forall extra. String -> Rewrite extra -> Rewrite extra
apply String
"reduceNonRepPrim" HasCallStack => NormRewrite
NormRewrite
reduceNonRepPrim NormRewrite -> NormRewrite -> NormRewrite
forall (m :: Type -> Type).
Monad m =>
Transform m -> Transform m -> Transform m
>->
                 String -> NormRewrite -> NormRewrite
forall extra. String -> Rewrite extra -> Rewrite extra
apply String
"removeUnusedExpr" HasCallStack => NormRewrite
NormRewrite
removeUnusedExpr NormRewrite -> NormRewrite -> NormRewrite
forall (m :: Type -> Type).
Monad m =>
Transform m -> Transform m -> Transform m
>->
                 String -> NormRewrite -> NormRewrite
forall extra. String -> Rewrite extra -> Rewrite extra
apply String
"flattenLet" HasCallStack => NormRewrite
NormRewrite
flattenLet)) NormRewrite -> NormRewrite -> NormRewrite
forall m. Rewrite m -> Rewrite m -> Rewrite m
!->
      NormRewrite -> NormRewrite
forall m. Rewrite m -> Rewrite m
topdownSucR (String -> NormRewrite -> NormRewrite
forall extra. String -> Rewrite extra -> Rewrite extra
apply String
"topLet" HasCallStack => NormRewrite
NormRewrite
topLet)

    goCheap :: CallTree -> (Maybe (Id, Term), [CallTree])
goCheap c :: CallTree
c@(CLeaf   (Id
nm2,(Binding Id
_ SrcSpan
_ InlineSpec
inl2 IsPrim
_ Term
e Bool
_)))
      | InlineSpec
inl2 InlineSpec -> InlineSpec -> Bool
forall a. Eq a => a -> a -> Bool
== InlineSpec
NoInline = (Maybe (Id, Term)
forall a. Maybe a
Nothing     ,[CallTree
c])
      | Bool
otherwise        = ((Id, Term) -> Maybe (Id, Term)
forall a. a -> Maybe a
Just (Id
nm2,Term
e),[])
    goCheap c :: CallTree
c@(CBranch (Id
nm2,(Binding Id
_ SrcSpan
_ InlineSpec
inl2 IsPrim
_ Term
e Bool
_)) [CallTree]
us)
      | InlineSpec
inl2 InlineSpec -> InlineSpec -> Bool
forall a. Eq a => a -> a -> Bool
== InlineSpec
NoInline = (Maybe (Id, Term)
forall a. Maybe a
Nothing, [CallTree
c])
      | Bool
otherwise        = ((Id, Term) -> Maybe (Id, Term)
forall a. a -> Maybe a
Just (Id
nm2,Term
e),[CallTree]
us)

callTreeToList :: [Id] -> CallTree -> ([Id], [(Id, Binding Term)])
callTreeToList :: [Id] -> CallTree -> ([Id], [(Id, Binding Term)])
callTreeToList [Id]
visited (CLeaf (Id
nm,Binding Term
bndr))
  | Id
nm Id -> [Id] -> Bool
forall (t :: Type -> Type) a.
(Foldable t, Eq a) =>
a -> t a -> Bool
`elem` [Id]
visited = ([Id]
visited,[])
  | Bool
otherwise         = (Id
nmId -> [Id] -> [Id]
forall a. a -> [a] -> [a]
:[Id]
visited,[(Id
nm,Binding Term
bndr)])
callTreeToList [Id]
visited (CBranch (Id
nm,Binding Term
bndr) [CallTree]
used)
  | Id
nm Id -> [Id] -> Bool
forall (t :: Type -> Type) a.
(Foldable t, Eq a) =>
a -> t a -> Bool
`elem` [Id]
visited = ([Id]
visited,[])
  | Bool
otherwise         = ([Id]
visited',(Id
nm,Binding Term
bndr)(Id, Binding Term) -> [(Id, Binding Term)] -> [(Id, Binding Term)]
forall a. a -> [a] -> [a]
:([[(Id, Binding Term)]] -> [(Id, Binding Term)]
forall (t :: Type -> Type) a. Foldable t => t [a] -> [a]
concat [[(Id, Binding Term)]]
others))
  where
    ([Id]
visited',[[(Id, Binding Term)]]
others) = ([Id] -> CallTree -> ([Id], [(Id, Binding Term)]))
-> [Id] -> [CallTree] -> ([Id], [[(Id, Binding Term)]])
forall (t :: Type -> Type) a b c.
Traversable t =>
(a -> b -> (a, c)) -> a -> t b -> (a, t c)
mapAccumL [Id] -> CallTree -> ([Id], [(Id, Binding Term)])
callTreeToList (Id
nmId -> [Id] -> [Id]
forall a. a -> [a] -> [a]
:[Id]
visited) [CallTree]
used