X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2FsimplCore%2FSimplEnv.lhs;h=865acdc98df9420d4766571c36c7bc3ac9fa7ca7;hb=5289f5d85610f71625a439747a09384876655eb5;hp=0a7575a890be2ca70255f76b5d721a1f98f2402e;hpb=4bc25e8c30559b7a6a87b39afcc79340ae778788;p=ghc-hetmet.git diff --git a/compiler/simplCore/SimplEnv.lhs b/compiler/simplCore/SimplEnv.lhs index 0a7575a..865acdc 100644 --- a/compiler/simplCore/SimplEnv.lhs +++ b/compiler/simplCore/SimplEnv.lhs @@ -5,12 +5,12 @@ \begin{code} module SimplEnv ( - InId, InBind, InExpr, InAlt, InArg, InType, InBndr, - OutId, OutTyVar, OutBind, OutExpr, OutAlt, OutArg, OutType, OutBndr, + InId, InBind, InExpr, InAlt, InArg, InType, InBndr, InVar, + OutId, OutTyVar, OutBind, OutExpr, OutAlt, OutArg, OutType, OutBndr, OutVar, InCoercion, OutCoercion, -- The simplifier mode - setMode, getMode, + setMode, getMode, updMode, -- Switch checker SwitchChecker, SwitchResult(..), getSwitchChecker, getSimplIntSwitch, @@ -19,17 +19,17 @@ module SimplEnv ( setEnclosingCC, getEnclosingCC, -- Environments - SimplEnv(..), pprSimplEnv, -- Temp not abstract + SimplEnv(..), StaticEnv, pprSimplEnv, -- Temp not abstract mkSimplEnv, extendIdSubst, SimplEnv.extendTvSubst, zapSubstEnv, setSubstEnv, getInScope, setInScope, setInScopeSet, modifyInScope, addNewInScopeIds, - getSimplRules, + getSimplRules, inGentleMode, SimplSR(..), mkContEx, substId, lookupRecBndr, simplNonRecBndr, simplRecBndrs, simplLamBndr, simplLamBndrs, simplBinder, simplBinders, addBndrRules, - substExpr, substWorker, substTy, + substExpr, substTy, substTyVar, getTvSubst, mkCoreSubst, -- Floats Floats, emptyFloats, isEmptyFloats, addNonRec, addFloats, extendFloats, @@ -40,6 +40,7 @@ module SimplEnv ( #include "HsVersions.h" import SimplMonad +import CoreMonad ( SimplifierMode(..) ) import IdInfo import CoreSyn import CoreUtils @@ -49,12 +50,11 @@ import VarEnv import VarSet import OrdList import Id -import qualified CoreSubst ( Subst, mkSubst, substExpr, substSpec, substWorker ) -import qualified Type ( substTy, substTyVarBndr ) -import Type hiding ( substTy, substTyVarBndr ) +import qualified CoreSubst +import qualified Type ( substTy, substTyVarBndr, substTyVar ) +import Type hiding ( substTy, substTyVarBndr, substTyVar ) import Coercion import BasicTypes -import DynFlags import MonadUtils import Outputable import FastString @@ -70,6 +70,7 @@ import Data.List \begin{code} type InBndr = CoreBndr +type InVar = Var -- Not yet cloned type InId = Id -- Not yet cloned type InType = Type -- Ditto type InBind = CoreBind @@ -79,6 +80,7 @@ type InArg = CoreArg type InCoercion = Coercion type OutBndr = CoreBndr +type OutVar = Var -- Cloned type OutId = Id -- Cloned type OutTyVar = TyVar -- Cloned type OutType = Type -- Cloned @@ -99,28 +101,43 @@ type OutArg = CoreArg \begin{code} data SimplEnv = SimplEnv { + ----------- Static part of the environment ----------- + -- Static in the sense of lexically scoped, + -- wrt the original expression + seMode :: SimplifierMode, seChkr :: SwitchChecker, seCC :: CostCentreStack, -- The enclosing CCS (when profiling) + -- The current substitution + seTvSubst :: TvSubstEnv, -- InTyVar |--> OutType + seIdSubst :: SimplIdSubst, -- InId |--> OutExpr + + ----------- Dynamic part of the environment ----------- + -- Dynamic in the sense of describing the setup where + -- the expression finally ends up + -- The current set of in-scope variables -- They are all OutVars, and all bound in this module seInScope :: InScopeSet, -- OutVars only -- Includes all variables bound by seFloats - seFloats :: Floats, + seFloats :: Floats -- See Note [Simplifier floats] - - -- The current substitution - seTvSubst :: TvSubstEnv, -- InTyVar |--> OutType - seIdSubst :: SimplIdSubst -- InId |--> OutExpr - } +type StaticEnv = SimplEnv -- Just the static part is relevant + pprSimplEnv :: SimplEnv -> SDoc -- Used for debugging; selective pprSimplEnv env = vcat [ptext (sLit "TvSubst:") <+> ppr (seTvSubst env), - ptext (sLit "IdSubst:") <+> ppr (seIdSubst env) ] + ptext (sLit "IdSubst:") <+> ppr (seIdSubst env), + ptext (sLit "InScope:") <+> vcat (map ppr_one in_scope_vars) + ] + where + in_scope_vars = varEnvElts (getInScopeVars (seInScope env)) + ppr_one v | isId v = ppr v <+> ppr (idUnfolding v) + | otherwise = ppr v type SimplIdSubst = IdEnv SimplSR -- IdId |--> OutExpr -- See Note [Extending the Subst] in CoreSubst @@ -143,7 +160,8 @@ instance Outputable SimplSR where -- keep uniq _ = uniq `elemUFM_Directly` fvs \end{code} - +Note [SimplEnv invariants] +~~~~~~~~~~~~~~~~~~~~~~~~~~ seInScope: The in-scope part of Subst includes *all* in-scope TyVars and Ids The elements of the set may have better IdInfo than the @@ -179,9 +197,8 @@ seIdSubst: * substId adds a binding (DoneId new_id) to the substitution if the Id's unique has changed - Note, though that the substitution isn't necessarily extended - if the type changes. Why not? Because of the next point: + if the type of the Id changes. Why not? Because of the next point: * We *always, always* finish by looking up in the in-scope set any variable that doesn't get a DoneEx or DoneVar hit in the substitution. @@ -206,8 +223,8 @@ seIdSubst: \begin{code} -mkSimplEnv :: SimplifierMode -> SwitchChecker -> SimplEnv -mkSimplEnv mode switches +mkSimplEnv :: SwitchChecker -> SimplifierMode -> SimplEnv +mkSimplEnv switches mode = SimplEnv { seChkr = switches, seCC = subsumedCCS, seMode = mode, seInScope = emptyInScopeSet, seFloats = emptyFloats, @@ -225,6 +242,14 @@ getMode env = seMode env setMode :: SimplifierMode -> SimplEnv -> SimplEnv setMode mode env = env { seMode = mode } +updMode :: (SimplifierMode -> SimplifierMode) -> SimplEnv -> SimplEnv +updMode upd env = env { seMode = upd (seMode env) } + +inGentleMode :: SimplEnv -> Bool +inGentleMode env = case seMode env of + SimplGently {} -> True + _other -> False + --------------------- getEnclosingCC :: SimplEnv -> CostCentreStack getEnclosingCC env = seCC env @@ -378,7 +403,9 @@ addNonRec :: SimplEnv -> OutId -> OutExpr -> SimplEnv -- in-scope set (although it might also have been created with newId) -- but it may now have more IdInfo addNonRec env id rhs - = env { seFloats = seFloats env `addFlts` unitFloat (NonRec id rhs), + = id `seq` -- This seq forces the Id, and hence its IdInfo, + -- and hence any inner substitutions + env { seFloats = seFloats env `addFlts` unitFloat (NonRec id rhs), seInScope = extendInScopeSet (seInScope env) id } extendFloats :: SimplEnv -> OutBind -> SimplEnv @@ -509,7 +536,7 @@ simplBinder :: SimplEnv -> InBndr -> SimplM (SimplEnv, OutBndr) -- The substitution is extended only if the variable is cloned, because -- we *don't* need to use it to track occurrence info. simplBinder env bndr - | isTyVar bndr = do { let (env', tv) = substTyVarBndr env bndr + | isTyCoVar bndr = do { let (env', tv) = substTyVarBndr env bndr ; seqTyVar tv `seq` return (env', tv) } | otherwise = do { let (env', id) = substIdBndr env bndr ; seqId id `seq` return (env', id) } @@ -656,33 +683,10 @@ addBndrRules env in_id out_id | isEmptySpecInfo old_rules = (env, out_id) | otherwise = (modifyInScope env final_id, final_id) where - subst = mkCoreSubst env + subst = mkCoreSubst (text "local rules") env old_rules = idSpecialisation in_id new_rules = CoreSubst.substSpec subst out_id old_rules final_id = out_id `setIdSpecialisation` new_rules - ------------------- -substIdType :: SimplEnv -> Id -> Id -substIdType (SimplEnv { seInScope = in_scope, seTvSubst = tv_env}) id - | isEmptyVarEnv tv_env || isEmptyVarSet (tyVarsOfType old_ty) = id - | otherwise = Id.setIdType id (Type.substTy (TvSubst in_scope tv_env) old_ty) - -- The tyVarsOfType is cheaper than it looks - -- because we cache the free tyvars of the type - -- in a Note in the id's type itself - where - old_ty = idType id - ------------------- -substUnfolding :: SimplEnv -> Unfolding -> Unfolding -substUnfolding _ NoUnfolding = NoUnfolding -substUnfolding _ (OtherCon cons) = OtherCon cons -substUnfolding env (CompulsoryUnfolding rhs) = CompulsoryUnfolding (substExpr env rhs) -substUnfolding env (CoreUnfolding rhs t u v w g) = CoreUnfolding (substExpr env rhs) t u v w g - ------------------- -substWorker :: SimplEnv -> WorkerInfo -> WorkerInfo -substWorker _ NoWorker = NoWorker -substWorker env wkr_info = CoreSubst.substWorker (mkCoreSubst env) wkr_info \end{code} @@ -693,13 +697,19 @@ substWorker env wkr_info = CoreSubst.substWorker (mkCoreSubst env) wkr_info %************************************************************************ \begin{code} +getTvSubst :: SimplEnv -> TvSubst +getTvSubst (SimplEnv { seInScope = in_scope, seTvSubst = tv_env }) + = mkTvSubst in_scope tv_env + substTy :: SimplEnv -> Type -> Type -substTy (SimplEnv { seInScope = in_scope, seTvSubst = tv_env }) ty - = Type.substTy (TvSubst in_scope tv_env) ty +substTy env ty = Type.substTy (getTvSubst env) ty + +substTyVar :: SimplEnv -> TyVar -> Type +substTyVar env tv = Type.substTyVar (getTvSubst env) tv substTyVarBndr :: SimplEnv -> TyVar -> (SimplEnv, TyVar) -substTyVarBndr env@(SimplEnv { seInScope = in_scope, seTvSubst = tv_env }) tv - = case Type.substTyVarBndr (TvSubst in_scope tv_env) tv of +substTyVarBndr env tv + = case Type.substTyVarBndr (getTvSubst env) tv of (TvSubst in_scope' tv_env', tv') -> (env { seInScope = in_scope', seTvSubst = tv_env'}, tv') @@ -708,19 +718,39 @@ substTyVarBndr env@(SimplEnv { seInScope = in_scope, seTvSubst = tv_env }) tv -- here. I think the this will not usually result in a lot of work; -- the substitutions are typically small, and laziness will avoid work in many cases. -mkCoreSubst :: SimplEnv -> CoreSubst.Subst -mkCoreSubst (SimplEnv { seInScope = in_scope, seTvSubst = tv_env, seIdSubst = id_env }) +mkCoreSubst :: SDoc -> SimplEnv -> CoreSubst.Subst +mkCoreSubst doc (SimplEnv { seInScope = in_scope, seTvSubst = tv_env, seIdSubst = id_env }) = mk_subst tv_env id_env where mk_subst tv_env id_env = CoreSubst.mkSubst in_scope tv_env (mapVarEnv fiddle id_env) fiddle (DoneEx e) = e fiddle (DoneId v) = Var v - fiddle (ContEx tv id e) = CoreSubst.substExpr (mk_subst tv id) e + fiddle (ContEx tv id e) = CoreSubst.substExpr (text "mkCoreSubst" <+> doc) (mk_subst tv id) e + -- Don't shortcut here + +------------------ +substIdType :: SimplEnv -> Id -> Id +substIdType (SimplEnv { seInScope = in_scope, seTvSubst = tv_env}) id + | isEmptyVarEnv tv_env || isEmptyVarSet (tyVarsOfType old_ty) = id + | otherwise = Id.setIdType id (Type.substTy (TvSubst in_scope tv_env) old_ty) + -- The tyVarsOfType is cheaper than it looks + -- because we cache the free tyvars of the type + -- in a Note in the id's type itself + where + old_ty = idType id + +------------------ +substExpr :: SDoc -> SimplEnv -> CoreExpr -> CoreExpr +substExpr doc env + = CoreSubst.substExpr (text "SimplEnv.substExpr1" <+> doc) + (mkCoreSubst (text "SimplEnv.substExpr2" <+> doc) env) + -- Do *not* short-cut in the case of an empty substitution + -- See Note [SimplEnv invariants] -substExpr :: SimplEnv -> CoreExpr -> CoreExpr -substExpr env expr = CoreSubst.substExpr (mkCoreSubst env) expr +substUnfolding :: SimplEnv -> Unfolding -> Unfolding +substUnfolding env unf = CoreSubst.substUnfolding (mkCoreSubst (text "subst-unfolding") env) unf -- Do *not* short-cut in the case of an empty substitution - -- See CoreSubst: Note [Extending the Subst] + -- See Note [SimplEnv invariants] \end{code}