diff options
Diffstat (limited to 'compiler/GHC/Types/Id.hs')
| -rw-r--r-- | compiler/GHC/Types/Id.hs | 64 |
1 files changed, 1 insertions, 63 deletions
diff --git a/compiler/GHC/Types/Id.hs b/compiler/GHC/Types/Id.hs index 01ad94172a..6135d02f9c 100644 --- a/compiler/GHC/Types/Id.hs +++ b/compiler/GHC/Types/Id.hs @@ -86,10 +86,8 @@ module GHC.Types.Id ( idInlineActivation, setInlineActivation, idRuleMatchInfo, -- ** One-shot lambdas - isOneShotBndr, isProbablyOneShotLambda, setOneShotLambda, clearOneShotLambda, updOneShotInfo, setIdOneShotInfo, - isStateHackType, stateHackOneShot, typeOneShot, -- ** Reading 'IdInfo' fields idArity, @@ -97,7 +95,7 @@ module GHC.Types.Id ( idUnfolding, realIdUnfolding, idSpecialisation, idCoreRules, idHasRules, idCafInfo, idLFInfo_maybe, - idOneShotInfo, idStateHackOneShotInfo, + idOneShotInfo, idOccInfo, -- ** Writing 'IdInfo' fields @@ -144,7 +142,6 @@ import qualified GHC.Types.Var as Var import GHC.Core.Type import GHC.Types.RepType -import GHC.Builtin.Types.Prim import GHC.Core.DataCon import GHC.Types.Demand import GHC.Types.Cpr @@ -165,7 +162,6 @@ import GHC.Utils.Misc import GHC.Utils.Outputable import GHC.Utils.Panic import GHC.Utils.Panic.Plain -import GHC.Utils.GlobalVars import GHC.Utils.Trace import GHC.Stg.InferTags.TagSig @@ -880,64 +876,6 @@ isConLikeId id = isConLike (idRuleMatchInfo id) idOneShotInfo :: Id -> OneShotInfo idOneShotInfo id = oneShotInfo (idInfo id) --- | Like 'idOneShotInfo', but taking the Horrible State Hack in to account --- See Note [The state-transformer hack] in "GHC.Core.Opt.Arity" -idStateHackOneShotInfo :: Id -> OneShotInfo -idStateHackOneShotInfo id - | isStateHackType (idType id) = stateHackOneShot - | otherwise = idOneShotInfo id - --- | Returns whether the lambda associated with the 'Id' is certainly applied at most once --- This one is the "business end", called externally. --- It works on type variables as well as Ids, returning True --- Its main purpose is to encapsulate the Horrible State Hack --- See Note [The state-transformer hack] in "GHC.Core.Opt.Arity" -isOneShotBndr :: Var -> Bool -isOneShotBndr var - | isTyVar var = True - | OneShotLam <- idStateHackOneShotInfo var = True - | otherwise = False - --- | Should we apply the state hack to values of this 'Type'? -stateHackOneShot :: OneShotInfo -stateHackOneShot = OneShotLam - -typeOneShot :: Type -> OneShotInfo -typeOneShot ty - | isStateHackType ty = stateHackOneShot - | otherwise = NoOneShotInfo - -isStateHackType :: Type -> Bool -isStateHackType ty - | unsafeHasNoStateHack - = False - | otherwise - = case tyConAppTyCon_maybe ty of - Just tycon -> tycon == statePrimTyCon - _ -> False - -- This is a gross hack. It claims that - -- every function over realWorldStatePrimTy is a one-shot - -- function. This is pretty true in practice, and makes a big - -- difference. For example, consider - -- a `thenST` \ r -> ...E... - -- The early full laziness pass, if it doesn't know that r is one-shot - -- will pull out E (let's say it doesn't mention r) to give - -- let lvl = E in a `thenST` \ r -> ...lvl... - -- When `thenST` gets inlined, we end up with - -- let lvl = E in \s -> case a s of (r, s') -> ...lvl... - -- and we don't re-inline E. - -- - -- It would be better to spot that r was one-shot to start with, but - -- I don't want to rely on that. - -- - -- Another good example is in fill_in in PrelPack.hs. We should be able to - -- spot that fill_in has arity 2 (and when Keith is done, we will) but we can't yet. - -isProbablyOneShotLambda :: Id -> Bool -isProbablyOneShotLambda id = case idStateHackOneShotInfo id of - OneShotLam -> True - NoOneShotInfo -> False - setOneShotLambda :: Id -> Id setOneShotLambda id = modifyIdInfo (`setOneShotInfo` OneShotLam) id |