-%
-% (c) The GRASP Project, Glasgow University, 1992-1998
-%
-\section[Rename]{Renaming and dependency analysis passes}
-
-\begin{code}
-module Rename ( renameModule ) where
-
-#include "HsVersions.h"
-
-import HsSyn
-import RdrHsSyn ( RdrNameHsModule )
-import RnHsSyn ( RenamedHsModule, RenamedHsDecl,
- extractHsTyNames, extractHsCtxtTyNames
- )
-
-import CmdLineOpts ( opt_HiMap, opt_D_dump_rn_trace,
- opt_D_dump_rn, opt_D_dump_rn_stats,
- opt_WarnUnusedBinds, opt_WarnUnusedImports
- )
-import RnMonad
-import RnNames ( getGlobalNames )
-import RnSource ( rnSourceDecls, rnDecl )
-import RnIfaces ( getImportedInstDecls, importDecl, getImportVersions,
- getImportedRules, loadHomeInterface, getSlurped
- )
-import RnEnv ( availName, availNames, availsToNameSet,
- warnUnusedTopNames, mapFvRn,
- FreeVars, plusFVs, plusFV, unitFV, emptyFVs, isEmptyFVs
- )
-import Module ( Module, ModuleName, pprModule, mkSearchPath, mkThisModule )
-import Name ( Name, isLocallyDefined,
- NamedThing(..), ImportReason(..), Provenance(..),
- pprOccName, nameOccName,
- getNameProvenance, occNameUserString,
- maybeWiredInTyConName, maybeWiredInIdName, isWiredInName
- )
-import Id ( idType )
-import DataCon ( dataConTyCon, dataConType )
-import TyCon ( TyCon, tyConDataCons, isSynTyCon, getSynTyConDefn )
-import RdrName ( RdrName )
-import NameSet
-import PrelMods ( mAIN_Name, pREL_MAIN_Name )
-import TysWiredIn ( unitTyCon, intTyCon, doubleTyCon, boolTyCon )
-import PrelInfo ( ioTyCon_NAME, thinAirIdNames )
-import Type ( namesOfType, funTyCon )
-import ErrUtils ( pprBagOfErrors, pprBagOfWarnings,
- doIfSet, dumpIfSet, ghcExit
- )
-import BasicTypes ( NewOrData(..) )
-import Bag ( isEmptyBag, bagToList )
-import FiniteMap ( fmToList, delListFromFM, addToFM, sizeFM, eltsFM )
-import UniqSupply ( UniqSupply )
-import Util ( equivClasses )
-import Maybes ( maybeToBool )
-import Outputable
-\end{code}
-
-
-
-\begin{code}
-renameModule :: UniqSupply
- -> RdrNameHsModule
- -> IO (Maybe
- ( Module
- , RenamedHsModule -- Output, after renaming
- , InterfaceDetails -- Interface; for interface file generation
- , RnNameSupply -- Final env; for renaming derivings
- , [ModuleName] -- Imported modules; for profiling
- ))
-
-renameModule us this_mod@(HsModule mod_name vers exports imports local_decls loc)
- = -- Initialise the renamer monad
- initRn mod_name us (mkSearchPath opt_HiMap) loc
- (rename this_mod) >>=
- \ (maybe_rn_stuff, rn_errs_bag, rn_warns_bag) ->
-
- -- Check for warnings
- doIfSet (not (isEmptyBag rn_warns_bag))
- (printErrs (pprBagOfWarnings rn_warns_bag)) >>
-
- -- Check for errors; exit if so
- doIfSet (not (isEmptyBag rn_errs_bag))
- (printErrs (pprBagOfErrors rn_errs_bag) >>
- ghcExit 1
- ) >>
-
- -- Dump output, if any
- (case maybe_rn_stuff of
- Nothing -> return ()
- Just results@(_, rn_mod, _, _, _)
- -> dumpIfSet opt_D_dump_rn "Renamer:"
- (ppr rn_mod)
- ) >>
-
- -- Return results
- return maybe_rn_stuff
-\end{code}
-
-
-\begin{code}
-rename this_mod@(HsModule mod_name vers exports imports local_decls loc)
- = -- FIND THE GLOBAL NAME ENVIRONMENT
- getGlobalNames this_mod `thenRn` \ maybe_stuff ->
-
- -- CHECK FOR EARLY EXIT
- if not (maybeToBool maybe_stuff) then
- -- Everything is up to date; no need to recompile further
- rnStats [] `thenRn_`
- returnRn Nothing
- else
- let
- Just (export_env, gbl_env, fixity_env, global_avail_env) = maybe_stuff
- in
-
- -- RENAME THE SOURCE
- initRnMS gbl_env fixity_env SourceMode (
- rnSourceDecls local_decls
- ) `thenRn` \ (rn_local_decls, source_fvs) ->
-
- -- SLURP IN ALL THE NEEDED DECLARATIONS
- let
- real_source_fvs = implicitFVs mod_name `plusFV` source_fvs
- -- It's important to do the "plus" this way round, so that
- -- when compiling the prelude, locally-defined (), Bool, etc
- -- override the implicit ones.
- in
- slurpImpDecls real_source_fvs `thenRn` \ rn_imp_decls ->
-
- -- EXIT IF ERRORS FOUND
- checkErrsRn `thenRn` \ no_errs_so_far ->
- if not no_errs_so_far then
- -- Found errors already, so exit now
- rnStats [] `thenRn_`
- returnRn Nothing
- else
-
- -- GENERATE THE VERSION/USAGE INFO
- getImportVersions mod_name exports `thenRn` \ my_usages ->
- getNameSupplyRn `thenRn` \ name_supply ->
-
- -- REPORT UNUSED NAMES
- reportUnusedNames gbl_env global_avail_env
- export_env
- source_fvs `thenRn_`
-
- -- RETURN THE RENAMED MODULE
- let
- has_orphans = any isOrphanDecl rn_local_decls
- direct_import_mods = [mod | ImportDecl mod _ _ _ _ _ <- imports]
- rn_all_decls = rn_imp_decls ++ rn_local_decls
- renamed_module = HsModule mod_name vers
- trashed_exports trashed_imports
- rn_all_decls
- loc
- in
- rnStats rn_imp_decls `thenRn_`
- returnRn (Just (mkThisModule mod_name,
- renamed_module,
- (has_orphans, my_usages, export_env),
- name_supply,
- direct_import_mods))
- where
- trashed_exports = {-trace "rnSource:trashed_exports"-} Nothing
- trashed_imports = {-trace "rnSource:trashed_imports"-} []
-\end{code}
-
-@implicitFVs@ forces the renamer to slurp in some things which aren't
-mentioned explicitly, but which might be needed by the type checker.
-
-\begin{code}
-implicitFVs mod_name
- = implicit_main `plusFV`
- mkNameSet default_tys `plusFV`
- mkNameSet thinAirIdNames
- where
- -- Add occurrences for Int, Double, and (), because they
- -- are the types to which ambigious type variables may be defaulted by
- -- the type checker; so they won't always appear explicitly.
- -- [The () one is a GHC extension for defaulting CCall results.]
- -- ALSO: funTyCon, since it occurs implicitly everywhere!
- -- (we don't want to be bothered with making funTyCon a
- -- free var at every function application!)
- default_tys = [getName intTyCon, getName doubleTyCon,
- getName unitTyCon, getName funTyCon, getName boolTyCon]
-
- -- Add occurrences for IO or PrimIO
- implicit_main | mod_name == mAIN_Name
- || mod_name == pREL_MAIN_Name = unitFV ioTyCon_NAME
- | otherwise = emptyFVs
-\end{code}
-
-\begin{code}
-isOrphanDecl (InstD (InstDecl inst_ty _ _ _ _))
- = not (foldNameSet ((||) . isLocallyDefined) False (extractHsTyNames inst_ty))
-isOrphanDecl (RuleD (RuleDecl _ _ _ lhs _ _))
- = check lhs
- where
- check (HsVar v) = not (isLocallyDefined v)
- check (HsApp f a) = check f && check a
- check other = True
-isOrphanDecl other = False
-\end{code}
-
-
-%*********************************************************
-%* *
-\subsection{Slurping declarations}
-%* *
-%*********************************************************
-
-\begin{code}
--------------------------------------------------------
-slurpImpDecls source_fvs
- = traceRn (text "slurpImp" <+> fsep (map ppr (nameSetToList source_fvs))) `thenRn_`
-
- -- The current slurped-set records all local things
- getSlurped `thenRn` \ source_binders ->
- slurpSourceRefs source_binders source_fvs `thenRn` \ (decls1, needed1, inst_gates) ->
-
- -- Now we can get the instance decls
- slurpInstDecls decls1 needed1 inst_gates `thenRn` \ (decls2, needed2) ->
-
- -- And finally get everything else
- closeDecls decls2 needed2
-
--------------------------------------------------------
-slurpSourceRefs :: NameSet -- Variables defined in source
- -> FreeVars -- Variables referenced in source
- -> RnMG ([RenamedHsDecl],
- FreeVars, -- Un-satisfied needs
- FreeVars) -- "Gates"
--- The declaration (and hence home module) of each gate has
--- already been loaded
-
-slurpSourceRefs source_binders source_fvs
- = go [] -- Accumulating decls
- emptyFVs -- Unsatisfied needs
- source_fvs -- Accumulating gates
- (nameSetToList source_fvs) -- Gates whose defn hasn't been loaded yet
- where
- go decls fvs gates []
- = returnRn (decls, fvs, gates)
-
- go decls fvs gates (wanted_name:refs)
- | isWiredInName wanted_name
- = load_home wanted_name `thenRn_`
- go decls fvs (gates `plusFV` getWiredInGates wanted_name) refs
-
- | otherwise
- = importDecl wanted_name `thenRn` \ maybe_decl ->
- case maybe_decl of
- -- No declaration... (already slurped, or local)
- Nothing -> go decls fvs gates refs
- Just decl -> rnIfaceDecl decl `thenRn` \ (new_decl, fvs1) ->
- let
- new_gates = getGates source_fvs new_decl
- in
- go (new_decl : decls)
- (fvs1 `plusFV` fvs)
- (gates `plusFV` new_gates)
- (nameSetToList new_gates ++ refs)
-
- -- When we find a wired-in name we must load its
- -- home module so that we find any instance decls therein
- load_home name
- | name `elemNameSet` source_binders = returnRn ()
- -- When compiling the prelude, a wired-in thing may
- -- be defined in this module, in which case we don't
- -- want to load its home module!
- -- Using 'isLocallyDefined' doesn't work because some of
- -- the free variables returned are simply 'listTyCon_Name',
- -- with a system provenance. We could look them up every time
- -- but that seems a waste.
- | otherwise = loadHomeInterface doc name `thenRn_`
- returnRn ()
- where
- doc = ptext SLIT("need home module for wired in thing") <+> ppr name
-
--------------------------------------------------------
--- slurpInstDecls imports appropriate instance decls.
--- It has to incorporate a loop, because consider
--- instance Foo a => Baz (Maybe a) where ...
--- It may be that Baz and Maybe are used in the source module,
--- but not Foo; so we need to chase Foo too.
-
-slurpInstDecls decls needed gates
- | isEmptyFVs gates
- = returnRn (decls, needed)
-
- | otherwise
- = getImportedInstDecls gates `thenRn` \ inst_decls ->
- rnInstDecls decls needed emptyFVs inst_decls `thenRn` \ (decls1, needed1, gates1) ->
- slurpInstDecls decls1 needed1 gates1
- where
- rnInstDecls decls fvs gates []
- = returnRn (decls, fvs, gates)
- rnInstDecls decls fvs gates (d:ds)
- = rnIfaceDecl d `thenRn` \ (new_decl, fvs1) ->
- rnInstDecls (new_decl:decls)
- (fvs1 `plusFV` fvs)
- (gates `plusFV` getInstDeclGates new_decl)
- ds
-
-
--------------------------------------------------------
--- closeDecls keeps going until the free-var set is empty
-closeDecls decls needed
- | not (isEmptyFVs needed)
- = slurpDecls decls needed `thenRn` \ (decls1, needed1) ->
- closeDecls decls1 needed1
-
- | otherwise
- = getImportedRules `thenRn` \ rule_decls ->
- case rule_decls of
- [] -> returnRn decls -- No new rules, so we are done
- other -> rnIfaceDecls decls emptyFVs rule_decls `thenRn` \ (decls1, needed1) ->
- closeDecls decls1 needed1
-
-
--------------------------------------------------------
-rnIfaceDecls :: [RenamedHsDecl] -> FreeVars
- -> [(Module, RdrNameHsDecl)]
- -> RnM d ([RenamedHsDecl], FreeVars)
-rnIfaceDecls decls fvs [] = returnRn (decls, fvs)
-rnIfaceDecls decls fvs (d:ds) = rnIfaceDecl d `thenRn` \ (new_decl, fvs1) ->
- rnIfaceDecls (new_decl:decls) (fvs1 `plusFV` fvs) ds
-
-rnIfaceDecl (mod, decl) = initIfaceRnMS mod (rnDecl decl)
-
-
--------------------------------------------------------
--- Augment decls with any decls needed by needed.
--- Return also free vars of the new decls (only)
-slurpDecls decls needed
- = go decls emptyFVs (nameSetToList needed)
- where
- go decls fvs [] = returnRn (decls, fvs)
- go decls fvs (ref:refs) = slurpDecl decls fvs ref `thenRn` \ (decls1, fvs1) ->
- go decls1 fvs1 refs
-
--------------------------------------------------------
-slurpDecl decls fvs wanted_name
- = importDecl wanted_name `thenRn` \ maybe_decl ->
- case maybe_decl of
- -- No declaration... (wired in thing)
- Nothing -> returnRn (decls, fvs)
-
- -- Found a declaration... rename it
- Just decl -> rnIfaceDecl decl `thenRn` \ (new_decl, fvs1) ->
- returnRn (new_decl:decls, fvs1 `plusFV` fvs)
-\end{code}
-
-
-%*********************************************************
-%* *
-\subsection{Extracting the 'gates'}
-%* *
-%*********************************************************
-
-When we import a declaration like
-
- data T = T1 Wibble | T2 Wobble
-
-we don't want to treat Wibble and Wobble as gates *unless* T1, T2
-respectively are mentioned by the user program. If only T is mentioned
-we want only T to be a gate; that way we don't suck in useless instance
-decls for (say) Eq Wibble, when they can't possibly be useful.
-
-@getGates@ takes a newly imported (and renamed) decl, and the free
-vars of the source program, and extracts from the decl the gate names.
-
-\begin{code}
-getGates source_fvs (SigD (IfaceSig _ ty _ _))
- = extractHsTyNames ty
-
-getGates source_fvs (TyClD (ClassDecl ctxt cls tvs sigs _ _ _ _ _ _))
- = delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) sigs)
- (map getTyVarName tvs)
- `addOneToNameSet` cls
- where
- get (ClassOpSig n _ ty _)
- | n `elemNameSet` source_fvs = extractHsTyNames ty
- | otherwise = emptyFVs
-
-getGates source_fvs (TyClD (TySynonym tycon tvs ty _))
- = delListFromNameSet (extractHsTyNames ty)
- (map getTyVarName tvs)
- -- A type synonym type constructor isn't a "gate" for instance decls
-
-getGates source_fvs (TyClD (TyData _ ctxt tycon tvs cons _ _ _))
- = delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) cons)
- (map getTyVarName tvs)
- `addOneToNameSet` tycon
- where
- get (ConDecl n tvs ctxt details _)
- | n `elemNameSet` source_fvs
- -- If the constructor is method, get fvs from all its fields
- = delListFromNameSet (get_details details `plusFV`
- extractHsCtxtTyNames ctxt)
- (map getTyVarName tvs)
- get (ConDecl n tvs ctxt (RecCon fields) _)
- -- Even if the constructor isn't mentioned, the fields
- -- might be, as selectors. They can't mention existentially
- -- bound tyvars (typechecker checks for that) so no need for
- -- the deleteListFromNameSet part
- = foldr (plusFV . get_field) emptyFVs fields
-
- get other_con = emptyFVs
-
- get_details (VanillaCon tys) = plusFVs (map get_bang tys)
- get_details (InfixCon t1 t2) = get_bang t1 `plusFV` get_bang t2
- get_details (RecCon fields) = plusFVs [get_bang t | (_, t) <- fields]
- get_details (NewCon t _) = extractHsTyNames t
-
- get_field (fs,t) | any (`elemNameSet` source_fvs) fs = get_bang t
- | otherwise = emptyFVs
-
- get_bang (Banged t) = extractHsTyNames t
- get_bang (Unbanged t) = extractHsTyNames t
- get_bang (Unpacked t) = extractHsTyNames t
-
-getGates source_fvs other_decl = emptyFVs
-\end{code}
-
-getWiredInGates is just like getGates, but it sees a wired-in Name
-rather than a declaration.
-
-\begin{code}
-getWiredInGates :: Name -> FreeVars
-getWiredInGates name -- No classes are wired in
- | is_id = getWiredInGates_s (namesOfType (idType the_id))
- | isSynTyCon the_tycon = getWiredInGates_s (delListFromNameSet (namesOfType ty) (map getName tyvars))
- | otherwise = unitFV name
- where
- maybe_wired_in_id = maybeWiredInIdName name
- is_id = maybeToBool maybe_wired_in_id
- maybe_wired_in_tycon = maybeWiredInTyConName name
- Just the_id = maybe_wired_in_id
- Just the_tycon = maybe_wired_in_tycon
- (tyvars,ty) = getSynTyConDefn the_tycon
-
-getWiredInGates_s names = foldr (plusFV . getWiredInGates) emptyFVs (nameSetToList names)
-\end{code}
-
-\begin{code}
-getInstDeclGates (InstD (InstDecl inst_ty _ _ _ _)) = extractHsTyNames inst_ty
-getInstDeclGates other = emptyFVs
-\end{code}
-
-
-%*********************************************************
-%* *
-\subsection{Unused names}
-%* *
-%*********************************************************
-
-\begin{code}
-reportUnusedNames gbl_env avail_env (ExportEnv export_avails _) mentioned_names
- | not (opt_WarnUnusedBinds || opt_WarnUnusedImports)
- = returnRn ()
-
- | otherwise
- = let
- used_names = mentioned_names `unionNameSets` availsToNameSet export_avails
-
- -- Now, a use of C implies a use of T,
- -- if C was brought into scope by T(..) or T(C)
- really_used_names = used_names `unionNameSets`
- mkNameSet [ availName avail
- | sub_name <- nameSetToList used_names,
- let avail = case lookupNameEnv avail_env sub_name of
- Just avail -> avail
- Nothing -> pprTrace "r.u.n" (ppr sub_name) $
- Avail sub_name
- ]
-
- defined_names = mkNameSet (concat (rdrEnvElts gbl_env))
- defined_but_not_used = nameSetToList (defined_names `minusNameSet` really_used_names)
-
- -- Filter out the ones only defined implicitly
- bad_guys = filter reportableUnusedName defined_but_not_used
- in
- warnUnusedTopNames bad_guys `thenRn_`
- returnRn ()
-
-reportableUnusedName :: Name -> Bool
-reportableUnusedName name
- = explicitlyImported (getNameProvenance name) &&
- not (startsWithUnderscore (occNameUserString (nameOccName name)))
- where
- explicitlyImported (LocalDef _ _) = True -- Report unused defns of local vars
- explicitlyImported (NonLocalDef (UserImport _ _ expl) _) = expl -- Report unused explicit imports
- explicitlyImported other = False -- Don't report others
-
- -- Haskell 98 encourages compilers to suppress warnings about
- -- unused names in a pattern if they start with "_".
- startsWithUnderscore ('_' : _) = True -- Suppress warnings for names starting
- startsWithUnderscore other = False -- with an underscore
-
-rnStats :: [RenamedHsDecl] -> RnMG ()
-rnStats imp_decls
- | opt_D_dump_rn_trace ||
- opt_D_dump_rn_stats ||
- opt_D_dump_rn
- = getRnStats imp_decls `thenRn` \ msg ->
- ioToRnM (printErrs msg) `thenRn_`
- returnRn ()
-
- | otherwise = returnRn ()
-\end{code}
-
-
-
-%*********************************************************
-%* *
-\subsection{Statistics}
-%* *
-%*********************************************************
-
-\begin{code}
-getRnStats :: [RenamedHsDecl] -> RnMG SDoc
-getRnStats imported_decls
- = getIfacesRn `thenRn` \ ifaces ->
- let
- n_mods = length [() | (_, _, Just _) <- eltsFM (iImpModInfo ifaces)]
-
- decls_read = [decl | (_, avail, True, (_,decl)) <- nameEnvElts (iDecls ifaces),
- -- Data, newtype, and class decls are in the decls_fm
- -- under multiple names; the tycon/class, and each
- -- constructor/class op too.
- -- The 'True' selects just the 'main' decl
- not (isLocallyDefined (availName avail))
- ]
-
- (cd_rd, dd_rd, nd_rd, sd_rd, vd_rd, _) = count_decls decls_read
- (cd_sp, dd_sp, nd_sp, sd_sp, vd_sp, id_sp) = count_decls imported_decls
-
- unslurped_insts = iInsts ifaces
- inst_decls_unslurped = length (bagToList unslurped_insts)
- inst_decls_read = id_sp + inst_decls_unslurped
-
- stats = vcat
- [int n_mods <+> text "interfaces read",
- hsep [ int cd_sp, text "class decls imported, out of",
- int cd_rd, text "read"],
- hsep [ int dd_sp, text "data decls imported, out of",
- int dd_rd, text "read"],
- hsep [ int nd_sp, text "newtype decls imported, out of",
- int nd_rd, text "read"],
- hsep [int sd_sp, text "type synonym decls imported, out of",
- int sd_rd, text "read"],
- hsep [int vd_sp, text "value signatures imported, out of",
- int vd_rd, text "read"],
- hsep [int id_sp, text "instance decls imported, out of",
- int inst_decls_read, text "read"],
- text "cls dcls slurp" <+> fsep (map (ppr . tyClDeclName)
- [d | TyClD d <- imported_decls, isClassDecl d]),
- text "cls dcls read" <+> fsep (map (ppr . tyClDeclName)
- [d | TyClD d <- decls_read, isClassDecl d])]
- in
- returnRn (hcat [text "Renamer stats: ", stats])
-
-count_decls decls
- = (class_decls,
- data_decls,
- newtype_decls,
- syn_decls,
- val_decls,
- inst_decls)
- where
- tycl_decls = [d | TyClD d <- decls]
- (class_decls, data_decls, newtype_decls, syn_decls) = countTyClDecls tycl_decls
-
- val_decls = length [() | SigD _ <- decls]
- inst_decls = length [() | InstD _ <- decls]
-\end{code}
-
+%\r
+% (c) The GRASP Project, Glasgow University, 1992-1998\r
+%\r
+\section[Rename]{Renaming and dependency analysis passes}\r
+\r
+\begin{code}\r
+module Rename ( renameModule ) where\r
+\r
+#include "HsVersions.h"\r
+\r
+import HsSyn\r
+import RdrHsSyn ( RdrNameHsModule )\r
+import RnHsSyn ( RenamedHsModule, RenamedHsDecl, \r
+ extractHsTyNames, extractHsCtxtTyNames\r
+ )\r
+\r
+import CmdLineOpts ( opt_HiMap, opt_D_dump_rn_trace,\r
+ opt_D_dump_rn, opt_D_dump_rn_stats,\r
+ opt_WarnUnusedBinds, opt_WarnUnusedImports\r
+ )\r
+import RnMonad\r
+import RnNames ( getGlobalNames )\r
+import RnSource ( rnSourceDecls, rnDecl )\r
+import RnIfaces ( getImportedInstDecls, importDecl, getImportVersions,\r
+ getImportedRules, loadHomeInterface, getSlurped\r
+ )\r
+import RnEnv ( availName, availNames, availsToNameSet, \r
+ warnUnusedTopNames, mapFvRn,\r
+ FreeVars, plusFVs, plusFV, unitFV, emptyFVs, isEmptyFVs\r
+ )\r
+import Module ( Module, ModuleName, pprModule, mkSearchPath, mkThisModule )\r
+import Name ( Name, isLocallyDefined,\r
+ NamedThing(..), ImportReason(..), Provenance(..),\r
+ pprOccName, nameOccName,\r
+ getNameProvenance, occNameUserString, \r
+ maybeWiredInTyConName, maybeWiredInIdName, isWiredInName\r
+ )\r
+import Id ( idType )\r
+import DataCon ( dataConTyCon, dataConType )\r
+import TyCon ( TyCon, tyConDataCons, isSynTyCon, getSynTyConDefn )\r
+import RdrName ( RdrName )\r
+import NameSet\r
+import PrelMods ( mAIN_Name, pREL_MAIN_Name )\r
+import TysWiredIn ( unitTyCon, intTyCon, doubleTyCon, boolTyCon )\r
+import PrelInfo ( ioTyCon_NAME, thinAirIdNames )\r
+import Type ( namesOfType, funTyCon )\r
+import ErrUtils ( pprBagOfErrors, pprBagOfWarnings,\r
+ doIfSet, dumpIfSet, ghcExit\r
+ )\r
+import BasicTypes ( NewOrData(..) )\r
+import Bag ( isEmptyBag, bagToList )\r
+import FiniteMap ( fmToList, delListFromFM, addToFM, sizeFM, eltsFM )\r
+import UniqSupply ( UniqSupply )\r
+import Util ( equivClasses )\r
+import Maybes ( maybeToBool )\r
+import Outputable\r
+\end{code}\r
+\r
+\r
+\r
+\begin{code}\r
+renameModule :: UniqSupply\r
+ -> RdrNameHsModule\r
+ -> IO (Maybe \r
+ ( Module\r
+ , RenamedHsModule -- Output, after renaming\r
+ , InterfaceDetails -- Interface; for interface file generation\r
+ , RnNameSupply -- Final env; for renaming derivings\r
+ , [ModuleName] -- Imported modules; for profiling\r
+ ))\r
+\r
+renameModule us this_mod@(HsModule mod_name vers exports imports local_decls loc)\r
+ = -- Initialise the renamer monad\r
+ initRn mod_name us (mkSearchPath opt_HiMap) loc\r
+ (rename this_mod) >>=\r
+ \ (maybe_rn_stuff, rn_errs_bag, rn_warns_bag) ->\r
+\r
+ -- Check for warnings\r
+ doIfSet (not (isEmptyBag rn_warns_bag))\r
+ (printErrs (pprBagOfWarnings rn_warns_bag)) >>\r
+\r
+ -- Check for errors; exit if so\r
+ doIfSet (not (isEmptyBag rn_errs_bag))\r
+ (printErrs (pprBagOfErrors rn_errs_bag) >>\r
+ ghcExit 1\r
+ ) >>\r
+\r
+ -- Dump output, if any\r
+ (case maybe_rn_stuff of\r
+ Nothing -> return ()\r
+ Just results@(_, rn_mod, _, _, _)\r
+ -> dumpIfSet opt_D_dump_rn "Renamer:"\r
+ (ppr rn_mod)\r
+ ) >>\r
+\r
+ -- Return results\r
+ return maybe_rn_stuff\r
+\end{code}\r
+\r
+\r
+\begin{code}\r
+rename this_mod@(HsModule mod_name vers exports imports local_decls loc)\r
+ = -- FIND THE GLOBAL NAME ENVIRONMENT\r
+ getGlobalNames this_mod `thenRn` \ maybe_stuff ->\r
+\r
+ -- CHECK FOR EARLY EXIT\r
+ if not (maybeToBool maybe_stuff) then\r
+ -- Everything is up to date; no need to recompile further\r
+ rnStats [] `thenRn_`\r
+ returnRn Nothing\r
+ else\r
+ let\r
+ Just (export_env, gbl_env, fixity_env, global_avail_env) = maybe_stuff\r
+ in\r
+\r
+ -- RENAME THE SOURCE\r
+ initRnMS gbl_env fixity_env SourceMode (\r
+ rnSourceDecls local_decls\r
+ ) `thenRn` \ (rn_local_decls, source_fvs) ->\r
+\r
+ -- SLURP IN ALL THE NEEDED DECLARATIONS\r
+ let\r
+ real_source_fvs = implicitFVs mod_name `plusFV` source_fvs\r
+ -- It's important to do the "plus" this way round, so that\r
+ -- when compiling the prelude, locally-defined (), Bool, etc\r
+ -- override the implicit ones. \r
+ in\r
+ slurpImpDecls real_source_fvs `thenRn` \ rn_imp_decls ->\r
+\r
+ -- EXIT IF ERRORS FOUND\r
+ checkErrsRn `thenRn` \ no_errs_so_far ->\r
+ if not no_errs_so_far then\r
+ -- Found errors already, so exit now\r
+ rnStats [] `thenRn_`\r
+ returnRn Nothing\r
+ else\r
+\r
+ -- GENERATE THE VERSION/USAGE INFO\r
+ getImportVersions mod_name exports `thenRn` \ my_usages ->\r
+ getNameSupplyRn `thenRn` \ name_supply ->\r
+\r
+ -- REPORT UNUSED NAMES\r
+ reportUnusedNames gbl_env global_avail_env\r
+ export_env\r
+ source_fvs `thenRn_`\r
+\r
+ -- RETURN THE RENAMED MODULE\r
+ let\r
+ has_orphans = any isOrphanDecl rn_local_decls\r
+ direct_import_mods = [mod | ImportDecl mod _ _ _ _ _ <- imports]\r
+ rn_all_decls = rn_imp_decls ++ rn_local_decls \r
+ renamed_module = HsModule mod_name vers \r
+ trashed_exports trashed_imports\r
+ rn_all_decls\r
+ loc\r
+ in\r
+ rnStats rn_imp_decls `thenRn_`\r
+ returnRn (Just (mkThisModule mod_name,\r
+ renamed_module, \r
+ (has_orphans, my_usages, export_env),\r
+ name_supply,\r
+ direct_import_mods))\r
+ where\r
+ trashed_exports = {-trace "rnSource:trashed_exports"-} Nothing\r
+ trashed_imports = {-trace "rnSource:trashed_imports"-} []\r
+\end{code}\r
+\r
+@implicitFVs@ forces the renamer to slurp in some things which aren't\r
+mentioned explicitly, but which might be needed by the type checker.\r
+\r
+\begin{code}\r
+implicitFVs mod_name\r
+ = implicit_main `plusFV` \r
+ mkNameSet default_tys `plusFV`\r
+ mkNameSet thinAirIdNames\r
+ where\r
+ -- Add occurrences for Int, Double, and (), because they\r
+ -- are the types to which ambigious type variables may be defaulted by\r
+ -- the type checker; so they won't always appear explicitly.\r
+ -- [The () one is a GHC extension for defaulting CCall results.]\r
+ -- ALSO: funTyCon, since it occurs implicitly everywhere!\r
+ -- (we don't want to be bothered with making funTyCon a\r
+ -- free var at every function application!)\r
+ default_tys = [getName intTyCon, getName doubleTyCon,\r
+ getName unitTyCon, getName funTyCon, getName boolTyCon]\r
+\r
+ -- Add occurrences for IO or PrimIO\r
+ implicit_main | mod_name == mAIN_Name\r
+ || mod_name == pREL_MAIN_Name = unitFV ioTyCon_NAME\r
+ | otherwise = emptyFVs\r
+\end{code}\r
+\r
+\begin{code}\r
+isOrphanDecl (InstD (InstDecl inst_ty _ _ _ _))\r
+ = not (foldNameSet ((||) . isLocallyDefined) False (extractHsTyNames inst_ty))\r
+isOrphanDecl (RuleD (RuleDecl _ _ _ lhs _ _))\r
+ = check lhs\r
+ where\r
+ check (HsVar v) = not (isLocallyDefined v)\r
+ check (HsApp f a) = check f && check a\r
+ check other = True\r
+isOrphanDecl other = False\r
+\end{code}\r
+\r
+\r
+%*********************************************************\r
+%* *\r
+\subsection{Slurping declarations}\r
+%* *\r
+%*********************************************************\r
+\r
+\begin{code}\r
+-------------------------------------------------------\r
+slurpImpDecls source_fvs\r
+ = traceRn (text "slurpImp" <+> fsep (map ppr (nameSetToList source_fvs))) `thenRn_`\r
+\r
+ -- The current slurped-set records all local things\r
+ getSlurped `thenRn` \ source_binders ->\r
+ slurpSourceRefs source_binders source_fvs `thenRn` \ (decls1, needed1, inst_gates) ->\r
+\r
+ -- Now we can get the instance decls\r
+ slurpInstDecls decls1 needed1 inst_gates `thenRn` \ (decls2, needed2) ->\r
+\r
+ -- And finally get everything else\r
+ closeDecls decls2 needed2\r
+\r
+-------------------------------------------------------\r
+slurpSourceRefs :: NameSet -- Variables defined in source\r
+ -> FreeVars -- Variables referenced in source\r
+ -> RnMG ([RenamedHsDecl],\r
+ FreeVars, -- Un-satisfied needs\r
+ FreeVars) -- "Gates"\r
+-- The declaration (and hence home module) of each gate has\r
+-- already been loaded\r
+\r
+slurpSourceRefs source_binders source_fvs\r
+ = go [] -- Accumulating decls\r
+ emptyFVs -- Unsatisfied needs\r
+ source_fvs -- Accumulating gates\r
+ (nameSetToList source_fvs) -- Gates whose defn hasn't been loaded yet\r
+ where\r
+ go decls fvs gates []\r
+ = returnRn (decls, fvs, gates)\r
+\r
+ go decls fvs gates (wanted_name:refs) \r
+ | isWiredInName wanted_name\r
+ = load_home wanted_name `thenRn_`\r
+ go decls fvs (gates `plusFV` getWiredInGates wanted_name) refs\r
+\r
+ | otherwise\r
+ = importDecl wanted_name `thenRn` \ maybe_decl ->\r
+ case maybe_decl of\r
+ -- No declaration... (already slurped, or local)\r
+ Nothing -> go decls fvs gates refs\r
+ Just decl -> rnIfaceDecl decl `thenRn` \ (new_decl, fvs1) ->\r
+ let\r
+ new_gates = getGates source_fvs new_decl\r
+ in\r
+ go (new_decl : decls)\r
+ (fvs1 `plusFV` fvs)\r
+ (gates `plusFV` new_gates)\r
+ (nameSetToList new_gates ++ refs)\r
+\r
+ -- When we find a wired-in name we must load its\r
+ -- home module so that we find any instance decls therein\r
+ load_home name \r
+ | name `elemNameSet` source_binders = returnRn ()\r
+ -- When compiling the prelude, a wired-in thing may\r
+ -- be defined in this module, in which case we don't\r
+ -- want to load its home module!\r
+ -- Using 'isLocallyDefined' doesn't work because some of\r
+ -- the free variables returned are simply 'listTyCon_Name',\r
+ -- with a system provenance. We could look them up every time\r
+ -- but that seems a waste.\r
+ | otherwise = loadHomeInterface doc name `thenRn_`\r
+ returnRn ()\r
+ where\r
+ doc = ptext SLIT("need home module for wired in thing") <+> ppr name\r
+\r
+-------------------------------------------------------\r
+-- slurpInstDecls imports appropriate instance decls.\r
+-- It has to incorporate a loop, because consider\r
+-- instance Foo a => Baz (Maybe a) where ...\r
+-- It may be that Baz and Maybe are used in the source module,\r
+-- but not Foo; so we need to chase Foo too.\r
+\r
+slurpInstDecls decls needed gates\r
+ | isEmptyFVs gates\r
+ = returnRn (decls, needed)\r
+\r
+ | otherwise\r
+ = getImportedInstDecls gates `thenRn` \ inst_decls ->\r
+ rnInstDecls decls needed emptyFVs inst_decls `thenRn` \ (decls1, needed1, gates1) ->\r
+ slurpInstDecls decls1 needed1 gates1\r
+ where\r
+ rnInstDecls decls fvs gates []\r
+ = returnRn (decls, fvs, gates)\r
+ rnInstDecls decls fvs gates (d:ds) \r
+ = rnIfaceDecl d `thenRn` \ (new_decl, fvs1) ->\r
+ rnInstDecls (new_decl:decls) \r
+ (fvs1 `plusFV` fvs)\r
+ (gates `plusFV` getInstDeclGates new_decl)\r
+ ds\r
+ \r
+\r
+-------------------------------------------------------\r
+-- closeDecls keeps going until the free-var set is empty\r
+closeDecls decls needed\r
+ | not (isEmptyFVs needed)\r
+ = slurpDecls decls needed `thenRn` \ (decls1, needed1) ->\r
+ closeDecls decls1 needed1\r
+\r
+ | otherwise\r
+ = getImportedRules `thenRn` \ rule_decls ->\r
+ case rule_decls of\r
+ [] -> returnRn decls -- No new rules, so we are done\r
+ other -> rnIfaceDecls decls emptyFVs rule_decls `thenRn` \ (decls1, needed1) ->\r
+ closeDecls decls1 needed1\r
+ \r
+\r
+-------------------------------------------------------\r
+rnIfaceDecls :: [RenamedHsDecl] -> FreeVars\r
+ -> [(Module, RdrNameHsDecl)]\r
+ -> RnM d ([RenamedHsDecl], FreeVars)\r
+rnIfaceDecls decls fvs [] = returnRn (decls, fvs)\r
+rnIfaceDecls decls fvs (d:ds) = rnIfaceDecl d `thenRn` \ (new_decl, fvs1) ->\r
+ rnIfaceDecls (new_decl:decls) (fvs1 `plusFV` fvs) ds\r
+\r
+rnIfaceDecl (mod, decl) = initIfaceRnMS mod (rnDecl decl) \r
+ \r
+\r
+-------------------------------------------------------\r
+-- Augment decls with any decls needed by needed.\r
+-- Return also free vars of the new decls (only)\r
+slurpDecls decls needed\r
+ = go decls emptyFVs (nameSetToList needed) \r
+ where\r
+ go decls fvs [] = returnRn (decls, fvs)\r
+ go decls fvs (ref:refs) = slurpDecl decls fvs ref `thenRn` \ (decls1, fvs1) ->\r
+ go decls1 fvs1 refs\r
+\r
+-------------------------------------------------------\r
+slurpDecl decls fvs wanted_name\r
+ = importDecl wanted_name `thenRn` \ maybe_decl ->\r
+ case maybe_decl of\r
+ -- No declaration... (wired in thing)\r
+ Nothing -> returnRn (decls, fvs)\r
+\r
+ -- Found a declaration... rename it\r
+ Just decl -> rnIfaceDecl decl `thenRn` \ (new_decl, fvs1) ->\r
+ returnRn (new_decl:decls, fvs1 `plusFV` fvs)\r
+\end{code}\r
+\r
+\r
+%*********************************************************\r
+%* *\r
+\subsection{Extracting the 'gates'}\r
+%* *\r
+%*********************************************************\r
+\r
+When we import a declaration like\r
+\r
+ data T = T1 Wibble | T2 Wobble\r
+\r
+we don't want to treat Wibble and Wobble as gates *unless* T1, T2\r
+respectively are mentioned by the user program. If only T is mentioned\r
+we want only T to be a gate; that way we don't suck in useless instance\r
+decls for (say) Eq Wibble, when they can't possibly be useful.\r
+\r
+@getGates@ takes a newly imported (and renamed) decl, and the free\r
+vars of the source program, and extracts from the decl the gate names.\r
+\r
+\begin{code}\r
+getGates source_fvs (SigD (IfaceSig _ ty _ _))\r
+ = extractHsTyNames ty\r
+\r
+getGates source_fvs (TyClD (ClassDecl ctxt cls tvs sigs _ _ _ _ _ _))\r
+ = delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) sigs)\r
+ (map getTyVarName tvs)\r
+ `addOneToNameSet` cls\r
+ where\r
+ get (ClassOpSig n _ ty _) \r
+ | n `elemNameSet` source_fvs = extractHsTyNames ty\r
+ | otherwise = emptyFVs\r
+\r
+getGates source_fvs (TyClD (TySynonym tycon tvs ty _))\r
+ = delListFromNameSet (extractHsTyNames ty)\r
+ (map getTyVarName tvs)\r
+ -- A type synonym type constructor isn't a "gate" for instance decls\r
+\r
+getGates source_fvs (TyClD (TyData _ ctxt tycon tvs cons _ _ _))\r
+ = delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) cons)\r
+ (map getTyVarName tvs)\r
+ `addOneToNameSet` tycon\r
+ where\r
+ get (ConDecl n tvs ctxt details _)\r
+ | n `elemNameSet` source_fvs\r
+ -- If the constructor is method, get fvs from all its fields\r
+ = delListFromNameSet (get_details details `plusFV` \r
+ extractHsCtxtTyNames ctxt)\r
+ (map getTyVarName tvs)\r
+ get (ConDecl n tvs ctxt (RecCon fields) _)\r
+ -- Even if the constructor isn't mentioned, the fields\r
+ -- might be, as selectors. They can't mention existentially\r
+ -- bound tyvars (typechecker checks for that) so no need for \r
+ -- the deleteListFromNameSet part\r
+ = foldr (plusFV . get_field) emptyFVs fields\r
+ \r
+ get other_con = emptyFVs\r
+\r
+ get_details (VanillaCon tys) = plusFVs (map get_bang tys)\r
+ get_details (InfixCon t1 t2) = get_bang t1 `plusFV` get_bang t2\r
+ get_details (RecCon fields) = plusFVs [get_bang t | (_, t) <- fields]\r
+ get_details (NewCon t _) = extractHsTyNames t\r
+\r
+ get_field (fs,t) | any (`elemNameSet` source_fvs) fs = get_bang t\r
+ | otherwise = emptyFVs\r
+\r
+ get_bang (Banged t) = extractHsTyNames t\r
+ get_bang (Unbanged t) = extractHsTyNames t\r
+ get_bang (Unpacked t) = extractHsTyNames t\r
+\r
+getGates source_fvs other_decl = emptyFVs\r
+\end{code}\r
+\r
+getWiredInGates is just like getGates, but it sees a wired-in Name\r
+rather than a declaration.\r
+\r
+\begin{code}\r
+getWiredInGates :: Name -> FreeVars\r
+getWiredInGates name -- No classes are wired in\r
+ | is_id = getWiredInGates_s (namesOfType (idType the_id))\r
+ | isSynTyCon the_tycon = getWiredInGates_s (delListFromNameSet (namesOfType ty) (map getName tyvars))\r
+ | otherwise = unitFV name\r
+ where\r
+ maybe_wired_in_id = maybeWiredInIdName name\r
+ is_id = maybeToBool maybe_wired_in_id\r
+ maybe_wired_in_tycon = maybeWiredInTyConName name\r
+ Just the_id = maybe_wired_in_id\r
+ Just the_tycon = maybe_wired_in_tycon\r
+ (tyvars,ty) = getSynTyConDefn the_tycon\r
+\r
+getWiredInGates_s names = foldr (plusFV . getWiredInGates) emptyFVs (nameSetToList names)\r
+\end{code}\r
+\r
+\begin{code}\r
+getInstDeclGates (InstD (InstDecl inst_ty _ _ _ _)) = extractHsTyNames inst_ty\r
+getInstDeclGates other = emptyFVs\r
+\end{code}\r
+\r
+\r
+%*********************************************************\r
+%* *\r
+\subsection{Unused names}\r
+%* *\r
+%*********************************************************\r
+\r
+\begin{code}\r
+reportUnusedNames gbl_env avail_env (ExportEnv export_avails _) mentioned_names\r
+ | not (opt_WarnUnusedBinds || opt_WarnUnusedImports)\r
+ = returnRn ()\r
+\r
+ | otherwise\r
+ = let\r
+ used_names = mentioned_names `unionNameSets` availsToNameSet export_avails\r
+\r
+ -- Now, a use of C implies a use of T,\r
+ -- if C was brought into scope by T(..) or T(C)\r
+ really_used_names = used_names `unionNameSets`\r
+ mkNameSet [ availName avail \r
+ | sub_name <- nameSetToList used_names,\r
+ let avail = case lookupNameEnv avail_env sub_name of\r
+ Just avail -> avail\r
+ Nothing -> pprTrace "r.u.n" (ppr sub_name) $\r
+ Avail sub_name\r
+ ]\r
+\r
+ defined_names = mkNameSet (concat (rdrEnvElts gbl_env))\r
+ defined_but_not_used = nameSetToList (defined_names `minusNameSet` really_used_names)\r
+\r
+ -- Filter out the ones only defined implicitly\r
+ bad_guys = filter reportableUnusedName defined_but_not_used\r
+ in\r
+ warnUnusedTopNames bad_guys `thenRn_`\r
+ returnRn ()\r
+\r
+reportableUnusedName :: Name -> Bool\r
+reportableUnusedName name\r
+ = explicitlyImported (getNameProvenance name) &&\r
+ not (startsWithUnderscore (occNameUserString (nameOccName name)))\r
+ where\r
+ explicitlyImported (LocalDef _ _) = True -- Report unused defns of local vars\r
+ explicitlyImported (NonLocalDef (UserImport _ _ expl) _) = expl -- Report unused explicit imports\r
+ explicitlyImported other = False -- Don't report others\r
+ \r
+ -- Haskell 98 encourages compilers to suppress warnings about\r
+ -- unused names in a pattern if they start with "_".\r
+ startsWithUnderscore ('_' : _) = True -- Suppress warnings for names starting\r
+ startsWithUnderscore other = False -- with an underscore\r
+\r
+rnStats :: [RenamedHsDecl] -> RnMG ()\r
+rnStats imp_decls\r
+ | opt_D_dump_rn_trace || \r
+ opt_D_dump_rn_stats ||\r
+ opt_D_dump_rn \r
+ = getRnStats imp_decls `thenRn` \ msg ->\r
+ ioToRnM (printErrs msg) `thenRn_`\r
+ returnRn ()\r
+\r
+ | otherwise = returnRn ()\r
+\end{code}\r
+\r
+\r
+\r
+%*********************************************************\r
+%* *\r
+\subsection{Statistics}\r
+%* *\r
+%*********************************************************\r
+\r
+\begin{code}\r
+getRnStats :: [RenamedHsDecl] -> RnMG SDoc\r
+getRnStats imported_decls\r
+ = getIfacesRn `thenRn` \ ifaces ->\r
+ let\r
+ n_mods = length [() | (_, _, Just _) <- eltsFM (iImpModInfo ifaces)]\r
+\r
+ decls_read = [decl | (_, avail, True, (_,decl)) <- nameEnvElts (iDecls ifaces),\r
+ -- Data, newtype, and class decls are in the decls_fm\r
+ -- under multiple names; the tycon/class, and each\r
+ -- constructor/class op too.\r
+ -- The 'True' selects just the 'main' decl\r
+ not (isLocallyDefined (availName avail))\r
+ ]\r
+\r
+ (cd_rd, dd_rd, nd_rd, sd_rd, vd_rd, _) = count_decls decls_read\r
+ (cd_sp, dd_sp, nd_sp, sd_sp, vd_sp, id_sp) = count_decls imported_decls\r
+\r
+ unslurped_insts = iInsts ifaces\r
+ inst_decls_unslurped = length (bagToList unslurped_insts)\r
+ inst_decls_read = id_sp + inst_decls_unslurped\r
+\r
+ stats = vcat \r
+ [int n_mods <+> text "interfaces read",\r
+ hsep [ int cd_sp, text "class decls imported, out of", \r
+ int cd_rd, text "read"],\r
+ hsep [ int dd_sp, text "data decls imported, out of", \r
+ int dd_rd, text "read"],\r
+ hsep [ int nd_sp, text "newtype decls imported, out of", \r
+ int nd_rd, text "read"],\r
+ hsep [int sd_sp, text "type synonym decls imported, out of", \r
+ int sd_rd, text "read"],\r
+ hsep [int vd_sp, text "value signatures imported, out of", \r
+ int vd_rd, text "read"],\r
+ hsep [int id_sp, text "instance decls imported, out of", \r
+ int inst_decls_read, text "read"],\r
+ text "cls dcls slurp" <+> fsep (map (ppr . tyClDeclName) \r
+ [d | TyClD d <- imported_decls, isClassDecl d]),\r
+ text "cls dcls read" <+> fsep (map (ppr . tyClDeclName) \r
+ [d | TyClD d <- decls_read, isClassDecl d])]\r
+ in\r
+ returnRn (hcat [text "Renamer stats: ", stats])\r
+\r
+count_decls decls\r
+ = (class_decls, \r
+ data_decls, \r
+ newtype_decls,\r
+ syn_decls, \r
+ val_decls, \r
+ inst_decls)\r
+ where\r
+ tycl_decls = [d | TyClD d <- decls]\r
+ (class_decls, data_decls, newtype_decls, syn_decls) = countTyClDecls tycl_decls\r
+\r
+ val_decls = length [() | SigD _ <- decls]\r
+ inst_decls = length [() | InstD _ <- decls]\r
+\end{code} \r
+\r
projects / ghc-hetmet.git / blobdiff