import CmdLineOpts ( DynFlags, DynFlag(..), opt_OmitInterfacePragmas )
import CoreSyn
import CoreUnfold ( noUnfolding, mkTopUnfolding, okToUnfoldInHiFile )
-import CoreUtils ( exprArity, exprIsBottom )
+import CoreUtils ( exprArity )
import CoreFVs ( ruleSomeFreeVars, exprSomeFreeVars )
import CoreLint ( showPass, endPass )
import VarEnv
import Var ( Id, Var )
import Id ( idType, idInfo, idName, isExportedId,
idCafInfo, mkId, isLocalId, isImplicitId,
- idFlavour, modifyIdInfo
+ idFlavour, modifyIdInfo, idArity
)
import IdInfo {- loads of stuff -}
import Name ( getOccName, nameOccName, globaliseName, setNameOcc,
- localiseName, mkLocalName, isGlobalName
+ localiseName, mkLocalName, isGlobalName, isDllName
)
import OccName ( TidyOccEnv, initTidyOccEnv, tidyOccName )
import Type ( tidyTopType, tidyType, tidyTyVar )
import PrimOp ( PrimOp(..), setCCallUnique )
import HscTypes ( PersistentCompilerState( pcs_PRS ),
PersistentRenamerState( prsOrig ),
- OrigNameEnv( origNames ), OrigNameNameEnv
+ NameSupply( nsNames ), OrigNameCache
)
import UniqSupply
+import DataCon ( DataCon, dataConName )
+import Literal ( isLitLitLit )
import FiniteMap ( lookupFM, addToFM )
import Maybes ( maybeToBool, orElse )
import ErrUtils ( showPass )
+import PprCore ( pprIdCoreRule )
import SrcLoc ( noSrcLoc )
import UniqFM ( mapUFM )
import Outputable
that all Ids are unique, rather than the weaker guarantee of
no clashes which the simplifier provides.
- - Give the Id its final IdInfo; in ptic,
+ - Give each dynamic CCall occurrence a fresh unique; this is
+ rather like the cloning step above.
+
+ - Give the Id its UTTERLY FINAL IdInfo; in ptic,
* Its flavour becomes ConstantId, reflecting the fact that
from now on we regard it as a constant, not local, Id
+
* its unfolding, if it should have one
+
+ * its arity, computed from the number of visible lambdas
+
+ * its CAF info, computed from what is free in its RHS
+
Finally, substitute these new top-level binders consistently
throughout, including in unfoldings. We also tidy binders in
; let (orphans_out, _)
= initUs us1 (tidyIdRules (occ_env,subst_env) orphans_in)
- ; let prs' = prs { prsOrig = orig { origNames = orig_env' } }
+ ; let prs' = prs { prsOrig = orig { nsNames = orig_env' } }
pcs' = pcs { pcs_PRS = prs' }
; endPass dflags "Tidy Core" Opt_D_dump_simpl binds_out
-- decl. tidyTopId then does a no-op on exported binders.
prs = pcs_PRS pcs
orig = prsOrig prs
- orig_env = origNames orig
+ orig_env = nsNames orig
init_tidy_env us = (us, orig_env, initTidyOccEnv avoids, emptyVarEnv)
avoids = [getOccName bndr | bndr <- bindersOfBinds binds_in,
\begin{code}
-type TopTidyEnv = (UniqSupply, OrigNameNameEnv, TidyOccEnv, VarEnv Var)
+type TopTidyEnv = (UniqSupply, OrigNameCache, TidyOccEnv, VarEnv Var)
-- TopTidyEnv: when tidying we need to know
-- * orig_env: Any pre-ordained Names. These may have arisen because the
tidyIdInfo us tidy_env is_external unfold_info arity_info caf_info id
| opt_OmitInterfacePragmas || not is_external
-- No IdInfo if the Id isn't external, or if we don't have -O
- = mkIdInfo new_flavour
+ = mkIdInfo new_flavour caf_info
`setStrictnessInfo` strictnessInfo core_idinfo
`setArityInfo` ArityExactly arity_info
- `setCafInfo` caf_info
-- Keep strictness, arity and CAF info; it's used by the code generator
| otherwise
= let (rules', _) = initUs us (tidyRules tidy_env (specInfo core_idinfo))
in
- mkIdInfo new_flavour
+ mkIdInfo new_flavour caf_info
`setCprInfo` cprInfo core_idinfo
`setStrictnessInfo` strictnessInfo core_idinfo
`setInlinePragInfo` inlinePragInfo core_idinfo
`setWorkerInfo` tidyWorker tidy_env arity_info (workerInfo core_idinfo)
`setSpecInfo` rules'
`setArityInfo` ArityExactly arity_info
- `setCafInfo` caf_info
-- this is the final IdInfo, it must agree with the
-- code finally generated (i.e. NO more transformations
-- after this!).
where
core_idinfo = idInfo id
-
+ new_flavour = makeConstantFlavour (flavourInfo core_idinfo)
-- A DFunId must stay a DFunId, so that we can gather the
-- DFunIds up later. Other local things become ConstantIds.
- new_flavour = case flavourInfo core_idinfo of
- VanillaId -> ConstantId
- ExportedId -> ConstantId
- ConstantId -> ConstantId -- e.g. Default methods
- DictFunId -> DictFunId
- flavour -> pprTrace "tidyIdInfo" (ppr id <+> ppFlavourInfo flavour)
- flavour
-- This is where we set names to local/global based on whether they really are
%* *
%************************************************************************
+hasCafRefs decides whether a top-level closure can point into the dynamic heap.
+We mark such things as `MayHaveCafRefs' because this information is
+used to decide whether a particular closure needs to be referenced
+in an SRT or not.
+
+There are two reasons for setting MayHaveCafRefs:
+ a) The RHS is a CAF: a top-level updatable thunk.
+ b) The RHS refers to something that MayHaveCafRefs
+
+Possible improvement: In an effort to keep the number of CAFs (and
+hence the size of the SRTs) down, we could also look at the expression and
+decide whether it requires a small bounded amount of heap, so we can ignore
+it as a CAF. In these cases however, we would need to use an additional
+CAF list to keep track of non-collectable CAFs.
+
\begin{code}
hasCafRefs :: (Id -> Bool) -> CoreExpr -> CafInfo
+-- Only called for the RHS of top-level lets
hasCafRefss :: (Id -> Bool) -> [CoreExpr] -> CafInfo
-- predicate returns True for a given Id if we look at this Id when
-- calculating the result. Used to *avoid* looking at the CafInfo
cafRefss p [] = fastBool False
cafRefss p (e:es) = cafRefs p e `fastOr` cafRefss p es
--- Decide whether a closure looks like a CAF or not. In an effort to
--- keep the number of CAFs (and hence the size of the SRTs) down, we
--- would also like to look at the expression and decide whether it
--- requires a small bounded amount of heap, so we can ignore it as a
--- CAF. In these cases however, we would need to use an additional
--- CAF list to keep track of non-collectable CAFs.
-
--- We mark real CAFs as `MayHaveCafRefs' because this information is
--- used to decide whether a particular closure needs to be referenced
--- in an SRT or not.
isCAF :: CoreExpr -> Bool
- -- special case for expressions which are always bottom,
- -- such as 'error "..."'. We don't need to record it as
- -- a CAF, since it can only be entered once.
-isCAF e
- | not_function && is_bottom = False
- | not_function && updatable = True
- | otherwise = False
+-- Only called for the RHS of top-level lets
+isCAF e = not (rhsIsNonUpd e)
+ {- ToDo: check type for onceness, i.e. non-updatable thunks? -}
+
+rhsIsNonUpd :: CoreExpr -> Bool
+ -- True => Value-lambda, constructor, PAP
+ -- This is a bit like CoreUtils.exprIsValue, with the following differences:
+ -- a) scc "foo" (\x -> ...) is updatable (so we catch the right SCC)
+ --
+ -- b) (C x xs), where C is a contructors is updatable if the application is
+ -- dynamic: see isDynConApp
+ --
+ -- c) don't look through unfolding of f in (f x). I'm suspicious of this one
+
+rhsIsNonUpd (Lam b e) = isId b || rhsIsNonUpd e
+rhsIsNonUpd (Note (SCC _) e) = False
+rhsIsNonUpd (Note _ e) = rhsIsNonUpd e
+rhsIsNonUpd other_expr
+ = go other_expr 0 []
where
- not_function = exprArity e == 0
- is_bottom = exprIsBottom e
- updatable = True {- ToDo: check type for onceness? -}
+ go (Var f) n_args args = idAppIsNonUpd f n_args args
+
+ go (App f a) n_args args
+ | isTypeArg a = go f n_args args
+ | otherwise = go f (n_args + 1) (a:args)
+
+ go (Note (SCC _) f) n_args args = False
+ go (Note _ f) n_args args = go f n_args args
+
+ go other n_args args = False
+
+idAppIsNonUpd :: Id -> Int -> [CoreExpr] -> Bool
+idAppIsNonUpd id n_val_args args
+ = case idFlavour id of
+ DataConId con | not (isDynConApp con args) -> True
+ other -> n_val_args < idArity id
+
+isDynConApp :: DataCon -> [CoreExpr] -> Bool
+isDynConApp con args = isDllName (dataConName con) || any isDynArg args
+-- Top-level constructor applications can usually be allocated
+-- statically, but they can't if
+-- a) the constructor, or any of the arguments, come from another DLL
+-- b) any of the arguments are LitLits
+-- (because we can't refer to static labels in other DLLs).
+-- If this happens we simply make the RHS into an updatable thunk,
+-- and 'exectute' it rather than allocating it statically.
+-- All this should match the decision in (see CoreToStg.coreToStgRhs)
+
+
+isDynArg :: CoreExpr -> Bool
+isDynArg (Var v) = isDllName (idName v)
+isDynArg (Note _ e) = isDynArg e
+isDynArg (Lit lit) = isLitLitLit lit
+isDynArg (App e _) = isDynArg e -- must be a type app
+isDynArg (Lam _ e) = isDynArg e -- must be a type lam
\end{code}
projects / ghc-hetmet.git / blobdiff