%
-% (c) The GRASP Project, Glasgow University, 1992-1996
+% (c) The GRASP Project, Glasgow University, 1992-1998
%
\section[Rename]{Renaming and dependency analysis passes}
\begin{code}
-#include "HsVersions.h"
-
module Rename ( renameModule ) where
-import PreludeGlaST ( thenPrimIO, newVar, MutableVar(..) )
-
-IMP_Ubiq()
+#include "HsVersions.h"
import HsSyn
-import RdrHsSyn ( RdrNameHsModule(..), RdrNameImportDecl(..) )
-import RnHsSyn ( RnName(..){-.. is for Ix hack only-}, RenamedHsModule(..), isRnTyConOrClass, isRnWired )
-
---ToDo:rm: all for debugging only
-import Maybes
-import Name
-import Outputable
-import RnIfaces
-import PprStyle
-import Pretty
-import FiniteMap
-import Util (pprPanic, pprTrace)
-
-import ParseUtils ( ParsedIface(..), RdrIfaceDecl(..), RdrIfaceInst(..),
- UsagesMap(..), VersionsMap(..)
+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_WarnDeprecations
+ )
import RnMonad
-import RnNames ( getGlobalNames, GlobalNameInfo(..) )
-import RnSource ( rnSource )
-import RnIfaces ( rnIfaces )
-import RnUtils ( RnEnv(..), extendGlobalRnEnv, emptyRnEnv )
-
-import Bag ( isEmptyBag, unionBags, unionManyBags, bagToList, listToBag )
-import CmdLineOpts ( opt_HiMap, opt_NoImplicitPrelude )
-import ErrUtils ( Error(..), Warning(..) )
-import FiniteMap ( emptyFM, eltsFM, fmToList, lookupFM{-ToDo:rm-} )
-import Maybes ( catMaybes )
-import Name ( isLocallyDefined, mkBuiltinName, Name, RdrName(..) )
-import PrelInfo ( builtinNameInfo, BuiltinNames(..), BuiltinKeys(..) )
-import PrelMods ( pRELUDE )
-import Unique ( ixClassKey )
-import UniqFM ( emptyUFM, lookupUFM, addListToUFM_C, eltsUFM )
-import UniqSupply ( splitUniqSupply )
-import Util ( panic, assertPanic )
+import RnNames ( getGlobalNames )
+import RnSource ( rnSourceDecls, rnDecl )
+import RnIfaces ( getImportedInstDecls, importDecl, getImportVersions,
+ getImportedRules, loadHomeInterface, getSlurped, removeContext
+ )
+import RnEnv ( availName, availsToNameSet,
+ warnUnusedImports, warnUnusedLocalBinds, lookupImplicitOccRn,
+ FreeVars, plusFVs, plusFV, unitFV, emptyFVs, isEmptyFVs
+ )
+import Module ( Module, ModuleName, mkSearchPath, mkThisModule )
+import Name ( Name, isLocallyDefined, NamedThing(..), getSrcLoc,
+ nameOccName, nameUnique, isUserImportedExplicitlyName,
+ maybeWiredInTyConName, maybeWiredInIdName, isWiredInName
+ )
+import OccName ( occNameFlavour )
+import Id ( idType )
+import TyCon ( isSynTyCon, getSynTyConDefn )
+import NameSet
+import PrelMods ( mAIN_Name, pREL_MAIN_Name )
+import TysWiredIn ( unitTyCon, intTyCon, doubleTyCon, boolTyCon )
+import PrelInfo ( ioTyCon_NAME, thinAirIdNames, fractionalClassKeys, derivingOccurrences )
+import Type ( namesOfType, funTyCon )
+import ErrUtils ( printErrorsAndWarnings, dumpIfSet, ghcExit )
+import BasicTypes ( NewOrData(..) )
+import Bag ( isEmptyBag, bagToList )
+import FiniteMap ( eltsFM )
+import UniqSupply ( UniqSupply )
+import UniqFM ( lookupUFM )
+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, dump_action), rn_errs_bag, rn_warns_bag) ->
+
+ -- Check for warnings
+ printErrorsAndWarnings rn_errs_bag rn_warns_bag >>
+
+ -- Dump any debugging output
+ dump_action >>
+
+ -- Return results
+ if not (isEmptyBag rn_errs_bag) then
+ ghcExit 1 >> return Nothing
+ else
+ return maybe_rn_stuff
+\end{code}
- -> IO (RenamedHsModule, -- output, after renaming
- RnEnv, -- final env (for renaming derivings)
- [Module], -- imported modules; for profiling
-
- (UsagesMap,
- VersionsMap, -- version info; for usage
- [Module]), -- instance modules; for iface
-
- Bag Error,
- Bag Warning)
-\end{code}
-
-ToDo: May want to arrange to return old interface for this module!
-ToDo: Deal with instances (instance version, this module on instance list ???)
\begin{code}
-renameModule us input@(HsModule mod _ _ imports _ _ _ _ _ _ _ _ _ _)
+rename :: RdrNameHsModule
+ -> RnMG (Maybe (Module, RenamedHsModule, InterfaceDetails, RnNameSupply, [ModuleName]), IO ())
+rename this_mod@(HsModule mod_name vers _ imports local_decls mod_deprec 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
+ rnDump [] [] `thenRn` \ dump_action ->
+ returnRn (Nothing, dump_action)
+ else
+ let
+ Just (export_env, gbl_env, fixity_env, global_avail_env) = maybe_stuff
+ in
- = let
- (b_names, b_keys, _) = builtinNameInfo
- pp_pair (n,m) = ppBesides [ppPStr m,ppChar '.',ppPStr n]
+ -- RENAME THE SOURCE
+ initRnMS gbl_env fixity_env SourceMode (
+ rnSourceDecls local_decls
+ ) `thenRn` \ (rn_local_decls, source_fvs) ->
+
+ -- SLURP IN ALL THE NEEDED DECLARATIONS
+ implicitFVs mod_name rn_local_decls `thenRn` \ implicit_fvs ->
+ let
+ real_source_fvs = implicit_fvs `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
- {-
- pprTrace "builtins:\n" (case b_names of { (builtin_ids, builtin_tcs) ->
- ppAboves [ ppCat (map pp_pair (keysFM builtin_ids))
- , ppCat (map pp_pair (keysFM builtin_tcs))
- , ppCat (map pp_pair (keysFM b_keys))
- ]}) $
- -}
- makeHiMap opt_HiMap >>= \ hi_files ->
--- pprTrace "HiMap:\n" (ppAboves [ ppCat [ppPStr m, ppStr p] | (m,p) <- fmToList hi_files])
- newVar (emptyFM,emptyFM,hi_files){-init iface cache-} `thenPrimIO` \ iface_cache ->
-
- fixIO ( \ ~(_, _, _, _, rec_occ_fm, rec_export_fn) ->
+ slurpImpDecls real_source_fvs `thenRn` \ rn_imp_decls ->
let
- rec_occ_fn :: Name -> [RdrName]
- rec_occ_fn n = case lookupUFM rec_occ_fm n of
- Nothing -> []
- Just (rn,occs) -> occs
+ rn_all_decls = rn_local_decls ++ rn_imp_decls
- global_name_info = (b_names, b_keys, rec_export_fn, rec_occ_fn)
+ -- COLLECT ALL DEPRECATIONS
+ deprec_sigs = [ ds | ValD bnds <- rn_local_decls, ds <- collectDeprecs bnds ]
+ deprecs = case mod_deprec of
+ Nothing -> deprec_sigs
+ Just txt -> Deprecation (IEModuleContents undefined) txt : deprec_sigs
in
- getGlobalNames iface_cache global_name_info us1 input >>=
- \ (occ_env, imp_mods, unqual_imps, imp_fixes, top_errs, top_warns) ->
- if not (isEmptyBag top_errs) then
- return (rn_panic, rn_panic, top_errs, top_warns, emptyUFM, rn_panic)
+ -- EXIT IF ERRORS FOUND
+ checkErrsRn `thenRn` \ no_errs_so_far ->
+ if not no_errs_so_far then
+ -- Found errors already, so exit now
+ rnDump rn_imp_decls rn_all_decls `thenRn` \ dump_action ->
+ returnRn (Nothing, dump_action)
else
- -- No top-level name errors so rename source ...
- case initRn True mod occ_env us2
- (rnSource imp_mods unqual_imps imp_fixes input) of {
- ((rn_module, export_fn, src_occs), src_errs, src_warns) ->
+ -- GENERATE THE VERSION/USAGE INFO
+ getImportVersions mod_name export_env `thenRn` \ my_usages ->
+ getNameSupplyRn `thenRn` \ name_supply ->
- --pprTrace "renameModule:" (ppCat (map (ppr PprDebug . fst) (bagToList src_occs))) $
+ -- REPORT UNUSED NAMES
+ reportUnusedNames gbl_env global_avail_env
+ export_env
+ source_fvs `thenRn_`
+ -- RETURN THE RENAMED MODULE
let
- occ_fm :: UniqFM (RnName, [RdrName])
-
- occ_list = [ (rn,(rn,[occ])) | (rn,occ) <- bagToList src_occs]
- occ_fm = addListToUFM_C insert_occ emptyUFM occ_list
-
- insert_occ (rn,olds) (rn',[new]) = (rn, insert new olds)
-
- insert new [] = [new]
- insert new xxs@(x:xs) = case cmp new x of LT_ -> new : xxs
- EQ_ -> xxs
- GT__ -> x : insert new xs
-
- occ_warns = map multipleOccWarn (filter multiple_occs (eltsUFM occ_fm))
- multiple_occs (rn, (o1:o2:_)) = True
- multiple_occs _ = False
+ has_orphans = any isOrphanDecl rn_local_decls
+ direct_import_mods = [mod | ImportDecl mod _ _ _ _ _ <- imports]
+ renamed_module = HsModule mod_name vers
+ trashed_exports trashed_imports
+ rn_all_decls
+ mod_deprec
+ loc
in
- return (rn_module, imp_mods,
- top_errs `unionBags` src_errs,
- top_warns `unionBags` src_warns `unionBags` listToBag occ_warns,
- occ_fm, export_fn)
+ rnDump rn_imp_decls rn_all_decls `thenRn` \ dump_action ->
+ returnRn (Just (mkThisModule mod_name,
+ renamed_module,
+ (InterfaceDetails has_orphans my_usages export_env deprecs),
+ name_supply,
+ direct_import_mods), dump_action)
+ where
+ trashed_exports = {-trace "rnSource:trashed_exports"-} Nothing
+ trashed_imports = {-trace "rnSource:trashed_imports"-} []
- }) >>= \ (rn_module, imp_mods, errs_so_far, warns_so_far, occ_fm, _) ->
+ collectDeprecs EmptyBinds = []
+ collectDeprecs (ThenBinds x y) = collectDeprecs x ++ collectDeprecs y
+ collectDeprecs (MonoBind _ sigs _) = [ d | DeprecSig d _ <- sigs ]
+\end{code}
- if not (isEmptyBag errs_so_far) then
- return (rn_panic, rn_panic, rn_panic, rn_panic, errs_so_far, warns_so_far)
- else
+@implicitFVs@ forces the renamer to slurp in some things which aren't
+mentioned explicitly, but which might be needed by the type checker.
- -- No errors renaming source so rename the interfaces ...
- let
- -- split up all names that occurred in the source; between
- -- those that are defined therein and those merely mentioned.
- -- We also divide by tycon/class and value names (as usual).
-
- occ_rns = [ rn | (rn,_) <- eltsUFM occ_fm ]
- -- all occurrence names, from this module and imported
-
- (defined_here, defined_elsewhere)
- = partition isLocallyDefined occ_rns
-
- (_, imports_used)
- = partition isRnWired defined_elsewhere
-
- (def_tcs, def_vals) = partition isRnTyConOrClass defined_here
- (occ_tcs, occ_vals) = partition isRnTyConOrClass occ_rns
- -- the occ stuff includes *all* occurrences,
- -- including those for which we have definitions
-
- (orig_def_env, orig_def_dups)
- = extendGlobalRnEnv emptyRnEnv (map pair_orig def_vals)
- (map pair_orig def_tcs)
- (orig_occ_env, orig_occ_dups)
- = extendGlobalRnEnv emptyRnEnv (map pair_orig occ_vals)
- (map pair_orig occ_tcs)
-
- pair_orig rn = (origName rn, rn)
-
- must_haves
- | opt_NoImplicitPrelude
- = [{-no Prelude.hi, no point looking-}]
- | otherwise
- = [ name_fn (mkBuiltinName u mod str)
- | ((str, mod), (u, name_fn)) <- fmToList b_keys,
- str `notElem` [ SLIT("main"), SLIT("mainPrimIO")] ]
- in
--- ASSERT (isEmptyBag orig_occ_dups)
- (if (isEmptyBag orig_occ_dups) then \x->x
- else pprTrace "orig_occ_dups:" (ppAboves [ ppCat [ppr PprDebug m, ppr PprDebug n, ppr PprDebug o] | (m,n,o) <- bagToList orig_occ_dups])) $
- ASSERT (isEmptyBag orig_def_dups)
-
- rnIfaces iface_cache imp_mods us3 orig_def_env orig_occ_env
- rn_module (must_haves ++ imports_used) >>=
- \ (rn_module_with_imports, final_env,
- (implicit_val_fm, implicit_tc_fm),
- usage_stuff,
- (iface_errs, iface_warns)) ->
-
- return (rn_module_with_imports,
- final_env,
- imp_mods,
- usage_stuff,
- errs_so_far `unionBags` iface_errs,
- warns_so_far `unionBags` iface_warns)
+\begin{code}
+implicitFVs mod_name decls
+ = mapRn lookupImplicitOccRn implicit_occs `thenRn` \ implicit_names ->
+ returnRn (implicit_main `plusFV`
+ mkNameSet (map getName default_tycons) `plusFV`
+ mkNameSet thinAirIdNames `plusFV`
+ mkNameSet implicit_names)
where
- rn_panic = panic "renameModule: aborted with errors"
-
- (us1, us') = splitUniqSupply us
- (us2, us3) = splitUniqSupply us'
+ -- Add occurrences for Int, 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!)
+ -- Double is dealt with separately in getGates
+ default_tycons = [unitTyCon, funTyCon, boolTyCon, intTyCon]
+
+ -- Add occurrences for IO or PrimIO
+ implicit_main | mod_name == mAIN_Name
+ || mod_name == pREL_MAIN_Name = unitFV ioTyCon_NAME
+ | otherwise = emptyFVs
+
+ -- Now add extra "occurrences" for things that
+ -- the deriving mechanism, or defaulting, will later need in order to
+ -- generate code
+ implicit_occs = foldr ((++) . get) [] decls
+
+ get (TyClD (TyData _ _ _ _ _ (Just deriv_classes) _ _))
+ = concat (map get_deriv deriv_classes)
+ get other = []
+
+ get_deriv cls = case lookupUFM derivingOccurrences cls of
+ Nothing -> []
+ Just occs -> occs
\end{code}
\begin{code}
-makeHiMap :: Maybe String -> IO (FiniteMap Module FilePath)
-
-makeHiMap Nothing = error "Rename.makeHiMap:no .hi map given by the GHC driver (?)"
-makeHiMap (Just f)
- = readFile f >>= \ cts ->
- return (snag_mod emptyFM cts [])
+isOrphanDecl (InstD (InstDecl inst_ty _ _ _ _))
+ = not (foldNameSet ((||) . isLocallyDefined) False (extractHsTyNames (removeContext inst_ty)))
+ -- The 'removeContext' is because of
+ -- instance Foo a => Baz T where ...
+ -- The decl is an orphan if Baz and T are both not locally defined,
+ -- even if Foo *is* locally defined
+
+isOrphanDecl (RuleD (RuleDecl _ _ _ lhs _ _))
+ = check lhs
where
- -- we alternate between "snag"ging mod(ule names) and path(names),
- -- accumulating names (reversed) and the final resulting map
- -- as we move along.
+ -- At the moment we just check for common LHS forms
+ -- Expand as necessary. Getting it wrong just means
+ -- more orphans than necessary
+ check (HsVar v) = not (isLocallyDefined v)
+ check (HsApp f a) = check f && check a
+ check (HsLit _) = False
+ check (OpApp l o _ r) = check l && check o && check r
+ check (NegApp e _) = check e
+ check (HsPar e) = check e
+ check (SectionL e o) = check e && check o
+ check (SectionR o e) = check e && check o
+
+ check other = True -- Safe fall through
+
+isOrphanDecl other = False
+\end{code}
- snag_mod map [] [] = map
- snag_mod map (' ':cs) rmod = snag_path map (_PK_ (reverse rmod)) cs []
- snag_mod map (c:cs) rmod = snag_mod map cs (c:rmod)
- snag_path map mod [] rpath = addToFM map mod (reverse rpath)
- snag_path map mod ('\n':cs) rpath = snag_mod (addToFM map mod (reverse rpath)) cs []
- snag_path map mod (c:cs) rpath = snag_path map mod cs (c:rpath)
+\begin{code}
+dupDefaultDeclErrRn (DefaultDecl _ locn1 : dup_things)
+ = pushSrcLocRn locn1 $
+ addErrRn msg
+ where
+ msg = hang (ptext SLIT("Multiple default declarations"))
+ 4 (vcat (map pp dup_things))
+ pp (DefaultDecl _ locn) = ptext SLIT("here was another default declaration") <+> ppr locn
\end{code}
-Warning message used herein:
+
+%*********************************************************
+%* *
+\subsection{Slurping declarations}
+%* *
+%*********************************************************
+
\begin{code}
-multipleOccWarn (name, occs) sty
- = ppBesides [ppStr "warning:multiple names used to refer to `", ppr sty name, ppStr "': ",
- ppInterleave ppComma (map (ppr sty) occs)]
+-------------------------------------------------------
+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` \ (decls, needed) ->
+
+ -- And finally get everything else
+ closeDecls decls needed
+
+-------------------------------------------------------
+slurpSourceRefs :: NameSet -- Variables defined in source
+ -> FreeVars -- Variables referenced in source
+ -> RnMG ([RenamedHsDecl],
+ FreeVars) -- Un-satisfied needs
+-- The declaration (and hence home module) of each gate has
+-- already been loaded
+
+slurpSourceRefs source_binders source_fvs
+ = go_outer [] -- Accumulating decls
+ emptyFVs -- Unsatisfied needs
+ emptyFVs -- Accumulating gates
+ (nameSetToList source_fvs) -- Things whose defn hasn't been loaded yet
+ where
+ -- The outer loop repeatedly slurps the decls for the current gates
+ -- and the instance decls
+
+ -- The outer loop is needed 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.
+ --
+ -- We also need to follow superclass refs. In particular, 'chasing @Foo@' must
+ -- include actually getting in Foo's class decl
+ -- class Wib a => Foo a where ..
+ -- so that its superclasses are discovered. The point is that Wib is a gate too.
+ -- We do this for tycons too, so that we look through type synonyms.
+
+ go_outer decls fvs all_gates []
+ = returnRn (decls, fvs)
+
+ go_outer decls fvs all_gates refs -- refs are not necessarily slurped yet
+ = traceRn (text "go_outer" <+> ppr refs) `thenRn_`
+ go_inner decls fvs emptyFVs refs `thenRn` \ (decls1, fvs1, gates1) ->
+ getImportedInstDecls (all_gates `plusFV` gates1) `thenRn` \ inst_decls ->
+ rnInstDecls decls1 fvs1 gates1 inst_decls `thenRn` \ (decls2, fvs2, gates2) ->
+ go_outer decls2 fvs2 (all_gates `plusFV` gates2)
+ (nameSetToList (gates2 `minusNameSet` all_gates))
+ -- Knock out the all_gates because even if we don't slurp any new
+ -- decls we can get some apparently-new gates from wired-in names
+
+ go_inner decls fvs gates []
+ = returnRn (decls, fvs, gates)
+
+ go_inner decls fvs gates (wanted_name:refs)
+ | isWiredInName wanted_name
+ = load_home wanted_name `thenRn_`
+ go_inner decls fvs (gates `plusFV` getWiredInGates wanted_name) refs
+
+ | otherwise
+ = importDecl wanted_name `thenRn` \ maybe_decl ->
+ case maybe_decl of
+ Nothing -> go_inner decls fvs gates refs -- No declaration... (already slurped, or local)
+ Just decl -> rnIfaceDecl decl `thenRn` \ (new_decl, fvs1) ->
+ go_inner (new_decl : decls)
+ (fvs1 `plusFV` fvs)
+ (gates `plusFV` getGates source_fvs new_decl)
+ 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
+
+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
\end{code}
+
\begin{code}
-{- TESTING:
-pprPIface (ParsedIface m ms v mv usgs lcm exm ims lfx ltdm lvdm lids ldp)
- = ppAboves [
- ppCat [ppPStr SLIT("interface"), ppPStr m, ppInt v,
- case mv of { Nothing -> ppNil; Just n -> ppInt n }],
-
- ppPStr SLIT("__versions__"),
- ppAboves [ ppCat[ppPStr n, ppInt v] | (n,v) <- fmToList lcm ],
-
- ppPStr SLIT("__exports__"),
- ppAboves [ ppBesides[ppPStr n, ppSP, ppr PprDebug rn,
- case ex of {ExportAll -> ppStr "(..)"; _ -> ppNil}]
- | (n,(rn,ex)) <- fmToList exm ],
-
- pp_ims (bagToList ims),
- pp_fixities lfx,
- pp_decls ltdm lvdm,
- pp_insts (bagToList lids),
- pp_pragmas ldp
- ]
+-------------------------------------------------------
+-- 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
- pp_ims [] = ppNil
- pp_ims ms = ppAbove (ppPStr SLIT("__instance_modules__"))
- (ppCat (map ppPStr ms))
+ 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}
- pp_fixities fx
- | isEmptyFM fx = ppNil
- | otherwise = ppAboves (ppPStr SLIT("__fixities__")
- : [ ppr PprDebug fix | (n, fix) <- fmToList fx])
- pp_decls tds vds = ppAboves (ppPStr SLIT("__declarations__")
- : [ pprRdrIfaceDecl d | (n, d) <- fmToList tds ++ fmToList vds])
+%*********************************************************
+%* *
+\subsection{Extracting the `gates'}
+%* *
+%*********************************************************
- pp_insts [] = ppNil
- pp_insts is = ppAboves (ppPStr SLIT("__instances__")
- : [ pprRdrInstDecl i | i <- is])
+When we import a declaration like
+\begin{verbatim}
+ data T = T1 Wibble | T2 Wobble
+\end{verbatim}
+we don't want to treat @Wibble@ and @Wobble@ as gates
+{\em 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.
- pp_pragmas ps | isEmptyFM ps = ppNil
- | otherwise = panic "Rename.pp_pragmas"
+@getGates@ takes a newly imported (and renamed) decl, and the free
+vars of the source program, and extracts from the decl the gate names.
-pprRdrIfaceDecl (TypeSig tc _ decl)
- = ppBesides [ppStr "tycon=", ppr PprDebug tc, ppStr "; ", ppr PprDebug decl]
+\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)
+ `plusFV` maybe_double
+ where
+ get (ClassOpSig n _ _ ty _)
+ | n `elemNameSet` source_fvs = extractHsTyNames ty
+ | otherwise = emptyFVs
+
+ -- If we load any numeric class that doesn't have
+ -- Int as an instance, add Double to the gates.
+ -- This takes account of the fact that Double might be needed for
+ -- defaulting, but we don't want to load Double (and all its baggage)
+ -- if the more exotic classes aren't used at all.
+ maybe_double | nameUnique cls `elem` fractionalClassKeys
+ = unitFV (getName doubleTyCon)
+ | 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}
-pprRdrIfaceDecl (NewTypeSig tc dc _ decl)
- = ppBesides [ppStr "tycon=", ppr PprDebug tc, ppStr "; datacon=", ppr PprDebug dc,
- ppStr "; ", ppr PprDebug decl]
+@getWiredInGates@ is just like @getGates@, but it sees a wired-in @Name@
+rather than a declaration.
-pprRdrIfaceDecl (DataSig tc dcs dfs _ decl)
- = ppBesides [ppStr "tycon=", ppr PprDebug tc, ppStr "; datacons=", ppr PprDebug dcs,
- ppStr "; fields=", ppr PprDebug dfs, ppStr "; ", ppr PprDebug decl]
+\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}
-pprRdrIfaceDecl (ClassSig c ops _ decl)
- = ppBesides [ppStr "class=", ppr PprDebug c, ppStr "; ops=", ppr PprDebug ops,
- ppStr "; ", ppr PprDebug decl]
-pprRdrIfaceDecl (ValSig f _ ty)
- = ppBesides [ppr PprDebug f, ppStr " :: ", ppr PprDebug ty]
+%*********************************************************
+%* *
+\subsection{Unused names}
+%* *
+%*********************************************************
-pprRdrInstDecl (InstSig c t _ decl)
- = ppBesides [ppStr "class=", ppr PprDebug c, ppStr " type=", ppr PprDebug t, ppStr "; ",
- ppr PprDebug decl]
--}
+\begin{code}
+reportUnusedNames :: GlobalRdrEnv -> NameEnv AvailInfo -> ExportEnv -> NameSet -> RnM d ()
+reportUnusedNames gbl_env avail_env (ExportEnv export_avails _ _) mentioned_names
+ = 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 -> WARN( True, text "reportUnusedName: not in avail_env" <+> 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_locals = [n | n <- defined_but_not_used, isLocallyDefined n]
+ bad_imps = [n | n <- defined_but_not_used, isUserImportedExplicitlyName n]
+
+ non_locally_used = [ n | n <- nameSetToList really_used_names, not (isLocallyDefined n) ]
+ deprec_used deprec_env = [ (n,txt) | n <- non_locally_used, Just txt <- [lookupNameEnv deprec_env n] ]
+ in
+ traceRn (text "really used and non-locally defined" <> colon <+>
+ nest 4 (fsep (punctuate comma [ text (occNameFlavour (nameOccName n)) <+> ppr n
+ | n <- non_locally_used]))) `thenRn_`
+ getIfacesRn `thenRn` \ ifaces ->
+ if opt_WarnDeprecations
+ then mapRn_ warnDeprec (deprec_used (iDeprecs ifaces))
+ else returnRn () `thenRn_`
+ warnUnusedLocalBinds bad_locals `thenRn_`
+ warnUnusedImports bad_imps
+
+warnDeprec :: (Name, DeprecTxt) -> RnM d ()
+warnDeprec (name, txt)
+ = pushSrcLocRn (getSrcLoc name) $
+ addWarnRn $
+ sep [ text "Using deprecated entity" <+> ppr name <> colon, nest 4 (ppr txt) ]
+
+rnDump :: [RenamedHsDecl] -- Renamed imported decls
+ -> [RenamedHsDecl] -- Renamed local decls
+ -> RnMG (IO ())
+rnDump imp_decls decls
+ | opt_D_dump_rn_trace ||
+ opt_D_dump_rn_stats ||
+ opt_D_dump_rn
+ = getRnStats imp_decls `thenRn` \ stats_msg ->
+
+ returnRn (printErrs stats_msg >>
+ dumpIfSet opt_D_dump_rn "Renamer:" (vcat (map ppr decls)))
+
+ | otherwise = returnRn (return ())
\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}
+