#include "HsVersions.h"
-import CoreUtils( exprIsAtom, exprType, exprIsValue, etaExpand, exprArity, exprOkForSpeculation )
+import CoreUtils( exprType, exprIsValue, etaExpand, exprArity, exprOkForSpeculation )
import CoreFVs ( exprFreeVars )
import CoreLint ( endPass )
import CoreSyn
-import Type ( Type, applyTy, splitFunTy_maybe, isTyVarTy,
- isUnLiftedType, isUnboxedTupleType, repType,
- uaUTy, usOnce, usMany, eqUsage, seqType )
+import Type ( Type, applyTy, splitFunTy_maybe,
+ isUnLiftedType, isUnboxedTupleType, seqType )
+import TcType ( TyThing( AnId ) )
import NewDemand ( Demand, isStrictDmd, lazyDmd, StrictSig(..), DmdType(..) )
-import PrimOp ( PrimOp(..) )
import Var ( Var, Id, setVarUnique )
import VarSet
import VarEnv
import Id ( mkSysLocal, idType, idNewDemandInfo, idArity,
- setIdType, isPrimOpId_maybe, isFCallId, isGlobalId,
- hasNoBinding, idNewStrictness,
- isDataConId_maybe, idUnfolding
+ isFCallId, isGlobalId, isImplicitId,
+ isLocalId, hasNoBinding, idNewStrictness,
+ idUnfolding, isDataConWorkId_maybe
)
-import HscTypes ( ModDetails(..), implicitTyThingIds, typeEnvElts )
-import Unique ( mkBuiltinUnique )
-import BasicTypes ( Arity, TopLevelFlag(..), isTopLevel, isNotTopLevel,
+import HscTypes ( TypeEnv, typeEnvElts )
+import BasicTypes ( TopLevelFlag(..), isTopLevel, isNotTopLevel,
RecFlag(..), isNonRec
)
import UniqSupply
4. Ensure that lambdas only occur as the RHS of a binding
(The code generator can't deal with anything else.)
-5. Do the seq/par munging. See notes with mkCase below.
+5. [Not any more; nuked Jun 2002] Do the seq/par munging.
+
+6. Clone all local Ids.
+ This means that all such Ids are unique, rather than the
+ weaker guarantee of no clashes which the simplifier provides.
+ And that is what the code generator needs.
+
+ We don't clone TyVars. The code gen doesn't need that,
+ and doing so would be tiresome because then we'd need
+ to substitute in types.
-6. Clone all local Ids. This means that Tidy Core has the property
- that all Ids are unique, rather than the weaker guarantee of
- no clashes which the simplifier provides.
7. Give each dynamic CCall occurrence a fresh unique; this is
rather like the cloning step above.
-- -----------------------------------------------------------------------------
\begin{code}
-corePrepPgm :: DynFlags -> ModDetails -> IO ModDetails
-corePrepPgm dflags mod_details
+corePrepPgm :: DynFlags -> [CoreBind] -> TypeEnv -> IO [CoreBind]
+corePrepPgm dflags binds types
= do showPass dflags "CorePrep"
us <- mkSplitUniqSupply 's'
- let implicit_binds = mkImplicitBinds (md_types mod_details)
+ let implicit_binds = mkImplicitBinds types
-- NB: we must feed mkImplicitBinds through corePrep too
-- so that they are suitably cloned and eta-expanded
binds_out = initUs_ us (
- corePrepTopBinds (md_binds mod_details) `thenUs` \ floats1 ->
- corePrepTopBinds implicit_binds `thenUs` \ floats2 ->
- returnUs (deFloatTop (floats1 `appOL` floats2))
+ corePrepTopBinds binds `thenUs` \ floats1 ->
+ corePrepTopBinds implicit_binds `thenUs` \ floats2 ->
+ returnUs (deFloatTop (floats1 `appendFloats` floats2))
)
endPass dflags "CorePrep" Opt_D_dump_prep binds_out
- return (mod_details { md_binds = binds_out })
+ return binds_out
corePrepExpr :: DynFlags -> CoreExpr -> IO CoreExpr
corePrepExpr dflags expr
\begin{code}
mkImplicitBinds type_env
= [ NonRec id (get_unfolding id)
- | id <- implicitTyThingIds (typeEnvElts type_env) ]
+ | AnId id <- typeEnvElts type_env, isImplicitId id ]
+ -- The type environment already contains all the implicit Ids,
+ -- so we just filter them out
+ --
-- The etaExpand is so that the manifest arity of the
-- binding matches its claimed arity, which is an
-- invariant of top level bindings going into the code gen
- where
- tmpl_uniqs = map mkBuiltinUnique [1..]
get_unfolding id -- See notes above
- | Just data_con <- isDataConId_maybe id = Var id -- The ice is thin here, but it works
- | otherwise = unfoldingTemplate (idUnfolding id)
+ | Just data_con <- isDataConWorkId_maybe id = Var id -- The ice is thin here, but it works
+ -- CorePrep will eta-expand it
+ | otherwise = unfoldingTemplate (idUnfolding id)
\end{code}
| FloatCase Id CoreExpr Bool
-- The bool indicates "ok-for-speculation"
+data Floats = Floats OkToSpec (OrdList FloatingBind)
+
+-- Can we float these binds out of the rhs of a let? We cache this decision
+-- to avoid having to recompute it in a non-linear way when there are
+-- deeply nested lets.
+data OkToSpec
+ = NotOkToSpec -- definitely not
+ | OkToSpec -- yes
+ | IfUnboxedOk -- only if floating an unboxed binding is ok
+
+emptyFloats :: Floats
+emptyFloats = Floats OkToSpec nilOL
+
+addFloat :: Floats -> FloatingBind -> Floats
+addFloat (Floats ok_to_spec floats) new_float
+ = Floats (combine ok_to_spec (check new_float)) (floats `snocOL` new_float)
+ where
+ check (FloatLet _) = OkToSpec
+ check (FloatCase _ _ ok_for_spec)
+ | ok_for_spec = IfUnboxedOk
+ | otherwise = NotOkToSpec
+ -- The ok-for-speculation flag says that it's safe to
+ -- float this Case out of a let, and thereby do it more eagerly
+ -- We need the top-level flag because it's never ok to float
+ -- an unboxed binding to the top level
+
+unitFloat :: FloatingBind -> Floats
+unitFloat = addFloat emptyFloats
+
+appendFloats :: Floats -> Floats -> Floats
+appendFloats (Floats spec1 floats1) (Floats spec2 floats2)
+ = Floats (combine spec1 spec2) (floats1 `appOL` floats2)
+
+concatFloats :: [Floats] -> Floats
+concatFloats = foldr appendFloats emptyFloats
+
+combine NotOkToSpec _ = NotOkToSpec
+combine _ NotOkToSpec = NotOkToSpec
+combine IfUnboxedOk _ = IfUnboxedOk
+combine _ IfUnboxedOk = IfUnboxedOk
+combine _ _ = OkToSpec
+
instance Outputable FloatingBind where
ppr (FloatLet bind) = text "FloatLet" <+> ppr bind
ppr (FloatCase b rhs spec) = text "FloatCase" <+> ppr b <+> ppr spec <+> equals <+> ppr rhs
type CloneEnv = IdEnv Id -- Clone local Ids
-deFloatTop :: OrdList FloatingBind -> [CoreBind]
+deFloatTop :: Floats -> [CoreBind]
-- For top level only; we don't expect any FloatCases
-deFloatTop floats
+deFloatTop (Floats _ floats)
= foldrOL get [] floats
where
get (FloatLet b) bs = b:bs
get b bs = pprPanic "corePrepPgm" (ppr b)
-allLazy :: TopLevelFlag -> RecFlag -> OrdList FloatingBind -> Bool
-allLazy top_lvl is_rec floats
- = foldrOL check True floats
- where
- unboxed_ok = isNotTopLevel top_lvl && isNonRec is_rec
-
- check (FloatLet _) y = y
- check (FloatCase _ _ ok_for_spec) y = unboxed_ok && ok_for_spec && y
- -- The ok-for-speculation flag says that it's safe to
- -- float this Case out of a let, and thereby do it more eagerly
- -- We need the top-level flag because it's never ok to float
- -- an unboxed binding to the top level
+allLazy :: TopLevelFlag -> RecFlag -> Floats -> Bool
+allLazy top_lvl is_rec (Floats ok_to_spec _)
+ = case ok_to_spec of
+ OkToSpec -> True
+ NotOkToSpec -> False
+ IfUnboxedOk -> isNotTopLevel top_lvl && isNonRec is_rec
-- ---------------------------------------------------------------------------
-- Bindings
-- ---------------------------------------------------------------------------
-corePrepTopBinds :: [CoreBind] -> UniqSM (OrdList FloatingBind)
+corePrepTopBinds :: [CoreBind] -> UniqSM Floats
corePrepTopBinds binds
= go emptyVarEnv binds
where
- go env [] = returnUs nilOL
+ go env [] = returnUs emptyFloats
go env (bind : binds) = corePrepTopBind env bind `thenUs` \ (env', bind') ->
go env' binds `thenUs` \ binds' ->
- returnUs (bind' `appOL` binds')
+ returnUs (bind' `appendFloats` binds')
-- NB: we do need to float out of top-level bindings
-- Consider x = length [True,False]
-- a = g y
-- x* = f a
-- And then x will actually end up case-bound
+--
+-- What happens to the CafInfo on the floated bindings? By
+-- default, all the CafInfos will be set to MayHaveCafRefs,
+-- which is safe.
+--
+-- This might be pessimistic, because eg. s1 & s2
+-- might not refer to any CAFs and the GC will end up doing
+-- more traversal than is necessary, but it's still better
+-- than not floating the bindings at all, because then
+-- the GC would have to traverse the structure in the heap
+-- instead. Given this, we decided not to try to get
+-- the CafInfo on the floated bindings correct, because
+-- it looks difficult.
--------------------------------
-corePrepTopBind :: CloneEnv -> CoreBind -> UniqSM (CloneEnv, OrdList FloatingBind)
+corePrepTopBind :: CloneEnv -> CoreBind -> UniqSM (CloneEnv, Floats)
corePrepTopBind env (NonRec bndr rhs)
= cloneBndr env bndr `thenUs` \ (env', bndr') ->
corePrepRhs TopLevel NonRecursive env (bndr, rhs) `thenUs` \ (floats, rhs') ->
- returnUs (env', floats `snocOL` FloatLet (NonRec bndr' rhs'))
+ returnUs (env', addFloat floats (FloatLet (NonRec bndr' rhs')))
corePrepTopBind env (Rec pairs) = corePrepRecPairs TopLevel env pairs
--------------------------------
-corePrepBind :: CloneEnv -> CoreBind -> UniqSM (CloneEnv, OrdList FloatingBind)
+corePrepBind :: CloneEnv -> CoreBind -> UniqSM (CloneEnv, Floats)
-- This one is used for *local* bindings
corePrepBind env (NonRec bndr rhs)
= etaExpandRhs bndr rhs `thenUs` \ rhs1 ->
--------------------------------
corePrepRecPairs :: TopLevelFlag -> CloneEnv
-> [(Id,CoreExpr)] -- Recursive bindings
- -> UniqSM (CloneEnv, OrdList FloatingBind)
+ -> UniqSM (CloneEnv, Floats)
-- Used for all recursive bindings, top level and otherwise
corePrepRecPairs lvl env pairs
= cloneBndrs env (map fst pairs) `thenUs` \ (env', bndrs') ->
mapAndUnzipUs (corePrepRhs lvl Recursive env') pairs `thenUs` \ (floats_s, rhss') ->
- returnUs (env', unitOL (FloatLet (Rec (flatten (concatOL floats_s) bndrs' rhss'))))
+ returnUs (env', unitFloat (FloatLet (Rec (flatten (concatFloats floats_s) bndrs' rhss'))))
where
-- Flatten all the floats, and the currrent
-- group into a single giant Rec
- flatten floats bndrs rhss = foldrOL get (bndrs `zip` rhss) floats
+ flatten (Floats _ floats) bndrs rhss = foldrOL get (bndrs `zip` rhss) floats
get (FloatLet (NonRec b r)) prs2 = (b,r) : prs2
get (FloatLet (Rec prs1)) prs2 = prs1 ++ prs2
--------------------------------
corePrepRhs :: TopLevelFlag -> RecFlag
-> CloneEnv -> (Id, CoreExpr)
- -> UniqSM (OrdList FloatingBind, CoreExpr)
+ -> UniqSM (Floats, CoreExpr)
-- Used for top-level bindings, and local recursive bindings
corePrepRhs top_lvl is_rec env (bndr, rhs)
= etaExpandRhs bndr rhs `thenUs` \ rhs' ->
-- This is where we arrange that a non-trivial argument is let-bound
corePrepArg :: CloneEnv -> CoreArg -> RhsDemand
- -> UniqSM (OrdList FloatingBind, CoreArg)
+ -> UniqSM (Floats, CoreArg)
corePrepArg env arg dem
= corePrepExprFloat env arg `thenUs` \ (floats, arg') ->
if exprIsTrivial arg'
mkBinds floats expr
-corePrepExprFloat :: CloneEnv -> CoreExpr -> UniqSM (OrdList FloatingBind, CoreExpr)
+corePrepExprFloat :: CloneEnv -> CoreExpr -> UniqSM (Floats, CoreExpr)
-- If
-- e ===> (bs, e')
-- then
= fiddleCCall v `thenUs` \ v1 ->
let v2 = lookupVarEnv env v1 `orElse` v1 in
maybeSaturate v2 (Var v2) 0 (idType v2) `thenUs` \ app ->
- returnUs (nilOL, app)
+ returnUs (emptyFloats, app)
corePrepExprFloat env expr@(Type _)
- = returnUs (nilOL, expr)
+ = returnUs (emptyFloats, expr)
corePrepExprFloat env expr@(Lit lit)
- = returnUs (nilOL, expr)
+ = returnUs (emptyFloats, expr)
corePrepExprFloat env (Let bind body)
= corePrepBind env bind `thenUs` \ (env', new_binds) ->
corePrepExprFloat env' body `thenUs` \ (floats, new_body) ->
- returnUs (new_binds `appOL` floats, new_body)
+ returnUs (new_binds `appendFloats` floats, new_body)
corePrepExprFloat env (Note n@(SCC _) expr)
= corePrepAnExpr env expr `thenUs` \ expr1 ->
- deLam expr1 `thenUs` \ expr2 ->
- returnUs (nilOL, Note n expr2)
+ deLamFloat expr1 `thenUs` \ (floats, expr2) ->
+ returnUs (floats, Note n expr2)
corePrepExprFloat env (Note other_note expr)
= corePrepExprFloat env expr `thenUs` \ (floats, expr') ->
returnUs (floats, Note other_note expr')
corePrepExprFloat env expr@(Lam _ _)
- = corePrepAnExpr env body `thenUs` \ body' ->
- returnUs (nilOL, mkLams bndrs body')
+ = cloneBndrs env bndrs `thenUs` \ (env', bndrs') ->
+ corePrepAnExpr env' body `thenUs` \ body' ->
+ returnUs (emptyFloats, mkLams bndrs' body')
where
(bndrs,body) = collectBinders expr
corePrepExprFloat env (Case scrut bndr alts)
- = corePrepExprFloat env scrut `thenUs` \ (floats, scrut') ->
+ = corePrepExprFloat env scrut `thenUs` \ (floats1, scrut1) ->
+ deLamFloat scrut1 `thenUs` \ (floats2, scrut2) ->
cloneBndr env bndr `thenUs` \ (env', bndr') ->
mapUs (sat_alt env') alts `thenUs` \ alts' ->
- returnUs (floats, mkCase scrut' bndr' alts')
+ returnUs (floats1 `appendFloats` floats2 , Case scrut2 bndr' alts')
where
sat_alt env (con, bs, rhs)
= cloneBndrs env bs `thenUs` \ (env', bs') ->
(CoreExpr,Int), -- the head of the application,
-- and no. of args it was applied to
Type, -- type of the whole expr
- OrdList FloatingBind, -- any floats we pulled out
+ Floats, -- any floats we pulled out
[Demand]) -- remaining argument demands
collect_args (App fun arg@(Type arg_ty)) depth
splitFunTy_maybe fun_ty
in
corePrepArg env arg (mkDemTy ss1 arg_ty) `thenUs` \ (fs, arg') ->
- returnUs (App fun' arg', hd, res_ty, fs `appOL` floats, ss_rest)
+ returnUs (App fun' arg', hd, res_ty, fs `appendFloats` floats, ss_rest)
collect_args (Var v) depth
= fiddleCCall v `thenUs` \ v1 ->
let v2 = lookupVarEnv env v1 `orElse` v1 in
- returnUs (Var v2, (Var v2, depth), idType v2, nilOL, stricts)
+ returnUs (Var v2, (Var v2, depth), idType v2, emptyFloats, stricts)
where
stricts = case idNewStrictness v of
StrictSig (DmdType _ demands _)
returnUs (Note note fun', hd, fun_ty, floats, ss)
-- non-variable fun, better let-bind it
+ -- ToDo: perhaps we can case-bind rather than let-bind this closure,
+ -- since it is sure to be evaluated.
collect_args fun depth
= corePrepExprFloat env fun `thenUs` \ (fun_floats, fun') ->
newVar ty `thenUs` \ fn_id ->
where
ty = exprType fun
- ignore_note InlineCall = True
- ignore_note InlineMe = True
- ignore_note _other = False
- -- we don't ignore SCCs, since they require some code generation
+ ignore_note (CoreNote _) = True
+ ignore_note InlineCall = True
+ ignore_note InlineMe = True
+ ignore_note _other = False
+ -- We don't ignore SCCs, since they require some code generation
------------------------------------------------------------------------------
-- Building the saturated syntax
floatRhs :: TopLevelFlag -> RecFlag
-> Id
- -> (OrdList FloatingBind, CoreExpr) -- Rhs: let binds in body
- -> UniqSM (OrdList FloatingBind, -- Floats out of this bind
- CoreExpr) -- Final Rhs
+ -> (Floats, CoreExpr) -- Rhs: let binds in body
+ -> UniqSM (Floats, -- Floats out of this bind
+ CoreExpr) -- Final Rhs
floatRhs top_lvl is_rec bndr (floats, rhs)
| isTopLevel top_lvl || exprIsValue rhs, -- Float to expose value or
| otherwise
-- Don't float; the RHS isn't a value
= mkBinds floats rhs `thenUs` \ rhs' ->
- returnUs (nilOL, rhs')
+ returnUs (emptyFloats, rhs')
-- mkLocalNonRec is used only for *nested*, *non-recursive* bindings
-mkLocalNonRec :: Id -> RhsDemand -- Lhs: id with demand
- -> OrdList FloatingBind -> CoreExpr -- Rhs: let binds in body
- -> UniqSM (OrdList FloatingBind)
+mkLocalNonRec :: Id -> RhsDemand -- Lhs: id with demand
+ -> Floats -> CoreExpr -- Rhs: let binds in body
+ -> UniqSM Floats
mkLocalNonRec bndr dem floats rhs
- | isUnLiftedType (idType bndr) || isStrict dem
- -- It's a strict let, or the binder is unlifted,
- -- so we definitely float all the bindings
+ | isUnLiftedType (idType bndr)
+ -- If this is an unlifted binding, we always make a case for it.
= ASSERT( not (isUnboxedTupleType (idType bndr)) )
- let -- Don't make a case for a value binding,
+ let
+ float = FloatCase bndr rhs (exprOkForSpeculation rhs)
+ in
+ returnUs (addFloat floats float)
+
+ | isStrict dem
+ -- It's a strict let so we definitely float all the bindings
+ = let -- Don't make a case for a value binding,
-- even if it's strict. Otherwise we get
-- case (\x -> e) of ...!
float | exprIsValue rhs = FloatLet (NonRec bndr rhs)
| otherwise = FloatCase bndr rhs (exprOkForSpeculation rhs)
in
- returnUs (floats `snocOL` float)
+ returnUs (addFloat floats float)
| otherwise
= floatRhs NotTopLevel NonRecursive bndr (floats, rhs) `thenUs` \ (floats', rhs') ->
- returnUs (floats' `snocOL` FloatLet (NonRec bndr rhs'))
+ returnUs (addFloat floats' (FloatLet (NonRec bndr rhs')))
where
bndr_ty = idType bndr
- bndr_rep_ty = repType bndr_ty
-mkBinds :: OrdList FloatingBind -> CoreExpr -> UniqSM CoreExpr
-mkBinds binds body
+
+mkBinds :: Floats -> CoreExpr -> UniqSM CoreExpr
+mkBinds (Floats _ binds) body
| isNilOL binds = returnUs body
| otherwise = deLam body `thenUs` \ body' ->
returnUs (foldrOL mk_bind body' binds)
where
- mk_bind (FloatCase bndr rhs _) body = mkCase rhs bndr [(DEFAULT, [], body)]
+ mk_bind (FloatCase bndr rhs _) body = Case rhs bndr [(DEFAULT, [], body)]
mk_bind (FloatLet bind) body = Let bind body
etaExpandRhs bndr rhs
-- We arrange that they only show up as the RHS of a let(rec)
-- ---------------------------------------------------------------------------
-deLam :: CoreExpr -> UniqSM CoreExpr
+deLam :: CoreExpr -> UniqSM CoreExpr
+deLam expr =
+ deLamFloat expr `thenUs` \ (floats, expr) ->
+ mkBinds floats expr
+
+
+deLamFloat :: CoreExpr -> UniqSM (Floats, CoreExpr)
-- Remove top level lambdas by let-bindinig
-deLam (Note n expr)
+deLamFloat (Note n expr)
= -- You can get things like
-- case e of { p -> coerce t (\s -> ...) }
- deLam expr `thenUs` \ expr' ->
- returnUs (Note n expr')
+ deLamFloat expr `thenUs` \ (floats, expr') ->
+ returnUs (floats, Note n expr')
-deLam expr
- | null bndrs = returnUs expr
+deLamFloat expr
+ | null bndrs = returnUs (emptyFloats, expr)
| otherwise
= case tryEta bndrs body of
- Just no_lam_result -> returnUs no_lam_result
+ Just no_lam_result -> returnUs (emptyFloats, no_lam_result)
Nothing -> newVar (exprType expr) `thenUs` \ fn ->
- returnUs (Let (NonRec fn expr) (Var fn))
+ returnUs (unitFloat (FloatLet (NonRec fn expr)),
+ Var fn)
where
(bndrs,body) = collectBinders expr
n_remaining = length args - length bndrs
ok bndr (Var arg) = bndr == arg
- ok bndr other = False
+ ok bndr other = False
-- we can't eta reduce something which must be saturated.
ok_to_eta_reduce (Var f) = not (hasNoBinding f)
-- -----------------------------------------------------------------------------
--- Do the seq and par transformation
--- -----------------------------------------------------------------------------
-
-Here we do two pre-codegen transformations:
-
-1. case seq# a of {
- 0 -> seqError ...
- DEFAULT -> rhs }
- ==>
- case a of { DEFAULT -> rhs }
-
-
-2. case par# a of {
- 0 -> parError ...
- DEFAULT -> rhs }
- ==>
- case par# a of {
- DEFAULT -> rhs }
-
-NB: seq# :: a -> Int# -- Evaluate value and return anything
- par# :: a -> Int# -- Spark value and return anything
-
-These transformations can't be done earlier, or else we might
-think that the expression was strict in the variables in which
-rhs is strict --- but that would defeat the purpose of seq and par.
-
-
-\begin{code}
-mkCase scrut@(Var fn `App` Type ty `App` arg) bndr alts@(deflt_alt@(DEFAULT,_,rhs) : con_alts)
- -- DEFAULT alt is always first
- = case isPrimOpId_maybe fn of
- Just ParOp -> Case scrut bndr [deflt_alt]
- Just SeqOp -> Case arg new_bndr [deflt_alt]
- other -> Case scrut bndr alts
- where
- -- The binder shouldn't be used in the expression!
- new_bndr = ASSERT2( not (bndr `elemVarSet` exprFreeVars rhs), ppr bndr )
- setIdType bndr (exprType arg)
- -- NB: SeqOp :: forall a. a -> Int#
- -- So bndr has type Int#
- -- But now we are going to scrutinise the SeqOp's argument directly,
- -- so we must change the type of the case binder to match that
- -- of the argument expression e.
-
-mkCase scrut bndr alts = Case scrut bndr alts
-\end{code}
-
-
--- -----------------------------------------------------------------------------
-- Demands
-- -----------------------------------------------------------------------------
mkDem strict once = RhsDemand (isStrictDmd strict) once
mkDemTy :: Demand -> Type -> RhsDemand
-mkDemTy strict ty = RhsDemand (isStrictDmd strict) (isOnceTy ty)
-
-isOnceTy :: Type -> Bool
-isOnceTy ty
- =
-#ifdef USMANY
- opt_UsageSPOn && -- can't expect annotations if -fusagesp is off
-#endif
- once
- where
- u = uaUTy ty
- once | u `eqUsage` usOnce = True
- | u `eqUsage` usMany = False
- | isTyVarTy u = False -- if unknown at compile-time, is Top ie usMany
+mkDemTy strict ty = RhsDemand (isStrictDmd strict)
+ False {- For now -}
bdrDem :: Id -> RhsDemand
-bdrDem id = mkDem (idNewDemandInfo id) (isOnceTy (idType id))
+bdrDem id = mkDem (idNewDemandInfo id)
+ False {- For now -}
+
+-- safeDem :: RhsDemand
+-- safeDem = RhsDemand False False -- always safe to use this
-safeDem, onceDem :: RhsDemand
-safeDem = RhsDemand False False -- always safe to use this
+onceDem :: RhsDemand
onceDem = RhsDemand False True -- used at most once
\end{code}
cloneBndr :: CloneEnv -> Var -> UniqSM (CloneEnv, Var)
cloneBndr env bndr
- | isGlobalId bndr -- Top level things, which we don't want
- = returnUs (env, bndr) -- to clone, have become GlobalIds by now
-
- | otherwise
+ | isLocalId bndr
= getUniqueUs `thenUs` \ uniq ->
let
bndr' = setVarUnique bndr uniq
in
returnUs (extendVarEnv env bndr bndr', bndr')
+ | otherwise -- Top level things, which we don't want
+ -- to clone, have become GlobalIds by now
+ -- And we don't clone tyvars
+ = returnUs (env, bndr)
+
+
------------------------------------------------------------------------------
-- Cloning ccall Ids; each must have a unique name,
-- to give the code generator a handle to hang it on
newVar ty
= seqType ty `seq`
getUniqueUs `thenUs` \ uniq ->
- returnUs (mkSysLocal SLIT("sat") uniq ty)
+ returnUs (mkSysLocal FSLIT("sat") uniq ty)
\end{code}
projects / ghc-hetmet.git / blobdiff