X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnIfaces.lhs;h=a56da3b240449171dee2e7471161d1c2596c8657;hb=bac531aaf56c7558eda70531e9565f753d21f848;hp=ddf4e4ef242d1341d66ff87b2f30bbc8f92bc930;hpb=451a8613203721d344e26eb043e8af827c58cd7b;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnIfaces.lhs b/ghc/compiler/rename/RnIfaces.lhs index ddf4e4e..a56da3b 100644 --- a/ghc/compiler/rename/RnIfaces.lhs +++ b/ghc/compiler/rename/RnIfaces.lhs @@ -4,517 +4,85 @@ \section[RnIfaces]{Cacheing and Renaming of Interfaces} \begin{code} -module RnIfaces ( - getInterfaceExports, - getImportedInstDecls, getImportedRules, - lookupFixity, loadHomeInterface, - importDecl, recordSlurp, - getImportVersions, getSlurped, +module RnIfaces + ( + getInterfaceExports, + recordLocalSlurps, + mkImportInfo, - checkUpToDate, + slurpImpDecls, closeDecls, - getDeclBinders - ) where + RecompileRequired, outOfDate, upToDate, recompileRequired + ) +where #include "HsVersions.h" -import CmdLineOpts ( opt_NoPruneDecls, opt_IgnoreIfacePragmas ) -import HsSyn ( HsDecl(..), TyClDecl(..), InstDecl(..), IfaceSig(..), - HsType(..), ConDecl(..), IE(..), ConDetails(..), Sig(..), - FixitySig(..), RuleDecl(..), - isClassOpSig +import CmdLineOpts ( DynFlags, opt_NoPruneDecls, opt_NoPruneTyDecls, opt_IgnoreIfacePragmas ) +import HscTypes +import HsSyn ( HsDecl(..), Sig(..), TyClDecl(..), ConDecl(..), ConDetails(..), + InstDecl(..), HsType(..), hsTyVarNames, getBangType ) -import BasicTypes ( Version, NewOrData(..), defaultFixity ) -import RdrHsSyn ( RdrNameHsDecl, RdrNameInstDecl, RdrNameTyClDecl, RdrNameRuleDecl, - extractHsTyRdrNames - ) -import RnEnv ( mkImportedGlobalName, newImportedBinder, mkImportedGlobalFromRdrName, - lookupOccRn, - pprAvail, - availName, availNames, addAvailToNameSet, - FreeVars, emptyFVs +import HsImpExp ( ImportDecl(..) ) +import RdrHsSyn ( RdrNameHsDecl, RdrNameTyClDecl, RdrNameInstDecl ) +import RnHsSyn ( RenamedHsDecl, extractHsTyNames, extractHsCtxtTyNames, tyClDeclFVs ) +import RnHiFiles ( tryLoadInterface, loadHomeInterface, loadInterface, + loadOrphanModules ) +import RnSource ( rnTyClDecl, rnDecl ) +import RnEnv import RnMonad -import RnHsSyn ( RenamedHsDecl ) -import ParseIface ( parseIface, IfaceStuff(..) ) - -import FiniteMap ( FiniteMap, sizeFM, emptyFM, delFromFM, - lookupFM, addToFM, addToFM_C, addListToFM, - fmToList, elemFM, foldFM - ) -import Name ( Name {-instance NamedThing-}, - nameModule, isLocallyDefined, - isWiredInName, nameUnique, NamedThing(..) +import Id ( idType ) +import Type ( namesOfType ) +import TyCon ( isSynTyCon, getSynTyConDefn ) +import Name ( Name {-instance NamedThing-}, nameOccName, + nameModule, isLocallyDefined, nameUnique, + NamedThing(..), + elemNameEnv ) -import Module ( Module, moduleString, pprModule, - mkVanillaModule, pprModuleName, - moduleUserString, moduleName, isLibModule, +import Module ( Module, ModuleEnv, + moduleName, isModuleInThisPackage, ModuleName, WhereFrom(..), + emptyModuleEnv, lookupModuleEnvByName, + extendModuleEnv_C, lookupWithDefaultModuleEnv ) -import RdrName ( RdrName, rdrNameOcc ) import NameSet -import Var ( Id ) -import SrcLoc ( mkSrcLoc, SrcLoc ) -import PrelMods ( pREL_GHC ) -import PrelInfo ( cCallishTyKeys, thinAirModules ) -import Bag -import Maybes ( MaybeErr(..), maybeToBool, orElse ) -import ListSetOps ( unionLists ) +import PrelInfo ( wiredInThingEnv, fractionalClassKeys ) +import TysWiredIn ( doubleTyCon ) +import Maybes ( orElse ) +import FiniteMap import Outputable -import Unique ( Unique ) -import StringBuffer ( StringBuffer, hGetStringBuffer ) -import FastString ( mkFastString ) -import Outputable - -import IO ( isDoesNotExistError ) -import List ( nub ) -\end{code} - - -%********************************************************* -%* * -\subsection{Loading a new interface file} -%* * -%********************************************************* - -\begin{code} -loadHomeInterface :: SDoc -> Name -> RnM d (Module, Ifaces) -loadHomeInterface doc_str name - = loadInterface doc_str (moduleName (nameModule name)) ImportBySystem - -loadInterface :: SDoc -> ModuleName -> WhereFrom -> RnM d (Module, Ifaces) -loadInterface doc_str mod_name from - = getIfacesRn `thenRn` \ ifaces -> - let - mod_map = iImpModInfo ifaces - mod_info = lookupFM mod_map mod_name - in_map = maybeToBool mod_info - in - - -- Issue a warning for a redundant {- SOURCE -} import - -- It's redundant if the moduld is in the iImpModInfo at all, - -- because we arrange to read all the ordinary imports before - -- any of the {- SOURCE -} imports - warnCheckRn (not (in_map && case from of {ImportByUserSource -> True; other -> False})) - (warnRedundantSourceImport mod_name) `thenRn_` - - -- CHECK WHETHER WE HAVE IT ALREADY - case mod_info of { - Just (_, _, Just (load_mod, _, _)) - -> -- We're read it already so don't re-read it - returnRn (load_mod, ifaces) ; - - mod_map_result -> - - -- READ THE MODULE IN - findAndReadIface doc_str mod_name from in_map `thenRn` \ (hi_boot_read, read_result) -> - case read_result of { - Nothing -> -- Not found, so add an empty export env to the Ifaces map - -- so that we don't look again - let - mod = mkVanillaModule mod_name - new_mod_map = addToFM mod_map mod_name (0, False, Just (mod, False, [])) - new_ifaces = ifaces { iImpModInfo = new_mod_map } - in - setIfacesRn new_ifaces `thenRn_` - failWithRn (mod, new_ifaces) (noIfaceErr mod hi_boot_read) ; - - -- Found and parsed! - Just (mod, iface) -> - - -- LOAD IT INTO Ifaces - - -- NB: *first* we do loadDecl, so that the provenance of all the locally-defined - --- names is done correctly (notably, whether this is an .hi file or .hi-boot file). - -- If we do loadExport first the wrong info gets into the cache (unless we - -- explicitly tag each export which seems a bit of a bore) - - getModuleRn `thenRn` \ this_mod_nm -> - let - rd_decls = pi_decls iface - in - foldlRn (loadDecl mod) (iDecls ifaces) rd_decls `thenRn` \ new_decls -> - foldlRn (loadInstDecl mod) (iInsts ifaces) (pi_insts iface) `thenRn` \ new_insts -> - foldlRn (loadRule mod) (iRules ifaces) (pi_rules iface) `thenRn` \ new_rules -> - foldlRn (loadFixDecl mod_name) (iFixes ifaces) rd_decls `thenRn` \ new_fixities -> - mapRn (loadExport this_mod_nm) (pi_exports iface) `thenRn` \ avails_s -> - let - -- For an explicit user import, add to mod_map info about - -- the things the imported module depends on, extracted - -- from its usage info. - mod_map1 = case from of - ImportByUser -> addModDeps mod mod_map (pi_usages iface) - other -> mod_map - - -- Now add info about this module - mod_map2 = addToFM mod_map1 mod_name mod_details - mod_details = (pi_mod iface, pi_orphan iface, Just (mod, hi_boot_read, concat avails_s)) - - new_ifaces = ifaces { iImpModInfo = mod_map2, - iDecls = new_decls, - iFixes = new_fixities, - iRules = new_rules, - iInsts = new_insts } - in - setIfacesRn new_ifaces `thenRn_` - returnRn (mod, new_ifaces) - }} - -addModDeps :: Module -> ImportedModuleInfo - -> [ImportVersion a] -> ImportedModuleInfo -addModDeps mod mod_deps new_deps - = foldr add mod_deps new_deps - where - is_lib = isLibModule mod -- Don't record dependencies when importing a library module - add (imp_mod, version, has_orphans, _) deps - | is_lib && not has_orphans = deps - | otherwise = addToFM_C combine deps imp_mod (version, has_orphans, Nothing) - -- Record dependencies for modules that are - -- either are dependent via a non-library module - -- or contain orphan rules or instance decls - - -- Don't ditch a module that's already loaded!! - combine old@(_, _, Just _) new = old - combine old@(_, _, Nothing) new = new - -loadExport :: ModuleName -> ExportItem -> RnM d [AvailInfo] -loadExport this_mod (mod, entities) - | mod == this_mod = returnRn [] - -- If the module exports anything defined in this module, just ignore it. - -- Reason: otherwise it looks as if there are two local definition sites - -- for the thing, and an error gets reported. Easiest thing is just to - -- filter them out up front. This situation only arises if a module - -- imports itself, or another module that imported it. (Necessarily, - -- this invoves a loop.) Consequence: if you say - -- module A where - -- import B( AType ) - -- type AType = ... - -- - -- module B( AType ) where - -- import {-# SOURCE #-} A( AType ) - -- - -- then you'll get a 'B does not export AType' message. A bit bogus - -- but it's a bogus thing to do! - - | otherwise - = mapRn (load_entity mod) entities - where - new_name mod occ = mkImportedGlobalName mod occ - - load_entity mod (Avail occ) - = new_name mod occ `thenRn` \ name -> - returnRn (Avail name) - load_entity mod (AvailTC occ occs) - = new_name mod occ `thenRn` \ name -> - mapRn (new_name mod) occs `thenRn` \ names -> - returnRn (AvailTC name names) - - -loadFixDecl :: ModuleName -> FixityEnv - -> (Version, RdrNameHsDecl) - -> RnM d FixityEnv -loadFixDecl mod_name fixity_env (version, FixD sig@(FixitySig rdr_name fixity loc)) - = -- Ignore the version; when the fixity changes the version of - -- its 'host' entity changes, so we don't need a separate version - -- number for fixities - mkImportedGlobalName mod_name (rdrNameOcc rdr_name) `thenRn` \ name -> - let - new_fixity_env = addToNameEnv fixity_env name (FixitySig name fixity loc) - in - returnRn new_fixity_env - - -- Ignore the other sorts of decl -loadFixDecl mod_name fixity_env other_decl = returnRn fixity_env - -loadDecl :: Module - -> DeclsMap - -> (Version, RdrNameHsDecl) - -> RnM d DeclsMap - -loadDecl mod decls_map (version, decl) - = getDeclBinders new_name decl `thenRn` \ maybe_avail -> - case maybe_avail of { - Nothing -> returnRn decls_map; -- No bindings - Just avail -> - - getDeclSysBinders new_name decl `thenRn` \ sys_bndrs -> - let - main_name = availName avail - new_decls_map = foldl add_decl decls_map - [ (name, (version, avail, name==main_name, (mod, decl'))) - | name <- sys_bndrs ++ availNames avail] - add_decl decls_map (name, stuff) - = WARN( name `elemNameEnv` decls_map, ppr name ) - addToNameEnv decls_map name stuff - in - returnRn new_decls_map - } - where - -- newImportedBinder puts into the cache the binder with the - -- module information set correctly. When the decl is later renamed, - -- the binding site will thereby get the correct module. - new_name rdr_name loc = newImportedBinder mod rdr_name - - {- - If a signature decl is being loaded, and optIgnoreIfacePragmas is on, - we toss away unfolding information. - - Also, if the signature is loaded from a module we're importing from source, - we do the same. This is to avoid situations when compiling a pair of mutually - recursive modules, peering at unfolding info in the interface file of the other, - e.g., you compile A, it looks at B's interface file and may as a result change - its interface file. Hence, B is recompiled, maybe changing its interface file, - which will the unfolding info used in A to become invalid. Simple way out is to - just ignore unfolding info. - - [Jan 99: I junked the second test above. If we're importing from an hi-boot - file there isn't going to *be* any pragma info. Maybe the above comment - dates from a time where we picked up a .hi file first if it existed?] - -} - decl' = case decl of - SigD (IfaceSig name tp ls loc) | opt_IgnoreIfacePragmas -> SigD (IfaceSig name tp [] loc) - other -> decl - -loadInstDecl :: Module - -> Bag GatedDecl - -> RdrNameInstDecl - -> RnM d (Bag GatedDecl) -loadInstDecl mod insts decl@(InstDecl inst_ty binds uprags dfun_name src_loc) - = - -- Find out what type constructors and classes are "gates" for the - -- instance declaration. If all these "gates" are slurped in then - -- we should slurp the instance decl too. - -- - -- We *don't* want to count names in the context part as gates, though. - -- For example: - -- instance Foo a => Baz (T a) where ... - -- - -- Here the gates are Baz and T, but *not* Foo. - let - munged_inst_ty = removeContext inst_ty - free_names = extractHsTyRdrNames munged_inst_ty - in - setModuleRn (moduleName mod) $ - mapRn mkImportedGlobalFromRdrName free_names `thenRn` \ gate_names -> - returnRn ((mkNameSet gate_names, (mod, InstD decl)) `consBag` insts) - - --- In interface files, the instance decls now look like --- forall a. Foo a -> Baz (T a) --- so we have to strip off function argument types as well --- as the bit before the '=>' (which is always empty in interface files) -removeContext (HsForAllTy tvs cxt ty) = HsForAllTy tvs [] (removeFuns ty) -removeContext ty = removeFuns ty - -removeFuns (MonoFunTy _ ty) = removeFuns ty -removeFuns ty = ty - - -loadRule :: Module -> Bag GatedDecl - -> RdrNameRuleDecl -> RnM d (Bag GatedDecl) --- "Gate" the rule simply by whether the rule variable is --- needed. We can refine this later. -loadRule mod rules decl@(IfaceRuleDecl var body src_loc) - = setModuleRn (moduleName mod) $ - mkImportedGlobalFromRdrName var `thenRn` \ var_name -> - returnRn ((unitNameSet var_name, (mod, RuleD decl)) `consBag` rules) -\end{code} - - -%******************************************************** -%* * -\subsection{Loading usage information} -%* * -%******************************************************** - -\begin{code} -checkUpToDate :: ModuleName -> RnMG Bool -- True <=> no need to recompile -checkUpToDate mod_name - = getIfacesRn `thenRn` \ ifaces -> - findAndReadIface doc_str mod_name - ImportByUser - (error "checkUpToDate") `thenRn` \ (_, read_result) -> - - -- CHECK WHETHER WE HAVE IT ALREADY - case read_result of - Nothing -> -- Old interface file not found, so we'd better bail out - traceRn (sep [ptext SLIT("Didnt find old iface"), - pprModuleName mod_name]) `thenRn_` - returnRn False - - Just (_, iface) - -> -- Found it, so now check it - checkModUsage (pi_usages iface) - where - -- Only look in current directory, with suffix .hi - doc_str = sep [ptext SLIT("need usage info from"), pprModuleName mod_name] - -checkModUsage [] = returnRn True -- Yes! Everything is up to date! - -checkModUsage ((mod_name, old_mod_vers, _, whats_imported) : rest) - = loadInterface doc_str mod_name ImportBySystem `thenRn` \ (mod, ifaces) -> - let - maybe_mod_vers = case lookupFM (iImpModInfo ifaces) mod_name of - Just (version, _, Just (_, _, _)) -> Just version - other -> Nothing - in - case maybe_mod_vers of { - Nothing -> -- If we can't find a version number for the old module then - -- bail out saying things aren't up to date - traceRn (sep [ptext SLIT("Can't find version number for module"), - pprModuleName mod_name]) `thenRn_` - returnRn False ; - - Just new_mod_vers -> - - -- If the module version hasn't changed, just move on - if new_mod_vers == old_mod_vers then - traceRn (sep [ptext SLIT("Module version unchanged:"), pprModuleName mod_name]) `thenRn_` - checkModUsage rest - else - traceRn (sep [ptext SLIT("Module version has changed:"), pprModuleName mod_name]) `thenRn_` - - -- Module version changed, so check entities inside - - -- If the usage info wants to say "I imported everything from this module" - -- it does so by making whats_imported equal to Everything - -- In that case, we must recompile - case whats_imported of { - Everything -> traceRn (ptext SLIT("...and I needed the whole module")) `thenRn_` - returnRn False; -- Bale out - - Specifically old_local_vers -> - - -- Non-empty usage list, so check item by item - checkEntityUsage mod_name (iDecls ifaces) old_local_vers `thenRn` \ up_to_date -> - if up_to_date then - traceRn (ptext SLIT("...but the bits I use haven't.")) `thenRn_` - checkModUsage rest -- This one's ok, so check the rest - else - returnRn False -- This one failed, so just bail out now - }} - where - doc_str = sep [ptext SLIT("need version info for"), pprModuleName mod_name] - - -checkEntityUsage mod decls [] - = returnRn True -- Yes! All up to date! - -checkEntityUsage mod decls ((occ_name,old_vers) : rest) - = mkImportedGlobalName mod occ_name `thenRn` \ name -> - case lookupNameEnv decls name of - - Nothing -> -- We used it before, but it ain't there now - putDocRn (sep [ptext SLIT("No longer exported:"), ppr name]) `thenRn_` - returnRn False - - Just (new_vers,_,_,_) -- It's there, but is it up to date? - | new_vers == old_vers - -- Up to date, so check the rest - -> checkEntityUsage mod decls rest - - | otherwise - -- Out of date, so bale out - -> putDocRn (sep [ptext SLIT("Out of date:"), ppr name]) `thenRn_` - returnRn False -\end{code} - - -%********************************************************* -%* * -\subsection{Getting in a declaration} -%* * -%********************************************************* - -\begin{code} -importDecl :: Name -> RnMG (Maybe (Module, RdrNameHsDecl)) - -- Returns Nothing for - -- (a) wired in name - -- (b) local decl - -- (c) already slurped - -importDecl name - | isWiredInName name - = returnRn Nothing - | otherwise - = getSlurped `thenRn` \ already_slurped -> - if name `elemNameSet` already_slurped then - returnRn Nothing -- Already dealt with - else - getModuleRn `thenRn` \ this_mod -> - let - mod = moduleName (nameModule name) - in - if mod == this_mod then -- Don't bring in decls from - -- the renamed module's own interface file - addWarnRn (importDeclWarn mod name) `thenRn_` - returnRn Nothing - else - getNonWiredInDecl name -\end{code} - -\begin{code} -getNonWiredInDecl :: Name -> RnMG (Maybe (Module, RdrNameHsDecl)) -getNonWiredInDecl needed_name - = traceRn doc_str `thenRn_` - loadHomeInterface doc_str needed_name `thenRn` \ (_, ifaces) -> - case lookupNameEnv (iDecls ifaces) needed_name of - - Just (version,avail,_,decl) - -> recordSlurp (Just version) avail `thenRn_` - returnRn (Just decl) +import Bag - Nothing -- Can happen legitimately for "Optional" occurrences - -> addErrRn (getDeclErr needed_name) `thenRn_` - returnRn Nothing - where - doc_str = ptext SLIT("need decl for") <+> ppr needed_name +import List ( nub ) \end{code} -@getWiredInDecl@ maps a wired-in @Name@ to what it makes available. -It behaves exactly as if the wired in decl were actually in an interface file. -Specifically, - - * if the wired-in name is a data type constructor or a data constructor, - it brings in the type constructor and all the data constructors; and - marks as "occurrences" any free vars of the data con. - - * similarly for synonum type constructor - - * if the wired-in name is another wired-in Id, it marks as "occurrences" - the free vars of the Id's type. - - * it loads the interface file for the wired-in thing for the - sole purpose of making sure that its instance declarations are available - -All this is necessary so that we know all types that are "in play", so -that we know just what instances to bring into scope. - - - %********************************************************* %* * \subsection{Getting what a module exports} %* * %********************************************************* -@getInterfaceExports@ is called only for directly-imported modules +@getInterfaceExports@ is called only for directly-imported modules. \begin{code} -getInterfaceExports :: ModuleName -> WhereFrom -> RnMG (Module, Avails) +getInterfaceExports :: ModuleName -> WhereFrom -> RnMG (Module, [(ModuleName,Avails)]) getInterfaceExports mod_name from - = loadInterface doc_str mod_name from `thenRn` \ (mod, ifaces) -> - case lookupFM (iImpModInfo ifaces) mod_name of - Nothing -> -- Not there; it must be that the interface file wasn't found; - -- the error will have been reported already. - -- (Actually loadInterface should put the empty export env in there - -- anyway, but this does no harm.) - returnRn (mod, []) - - Just (_, _, Just (mod, _, avails)) -> returnRn (mod, avails) - where - doc_str = sep [pprModuleName mod_name, ptext SLIT("is directly imported")] + = getHomeIfaceTableRn `thenRn` \ hit -> + case lookupModuleEnvByName hit mod_name of { + Just mi -> returnRn (mi_module mi, mi_exports mi) ; + Nothing -> + + loadInterface doc_str mod_name from `thenRn` \ ifaces -> + case lookupModuleEnvByName (iPIT ifaces) mod_name of + Just mi -> returnRn (mi_module mi, mi_exports mi) ; + -- loadInterface always puts something in the map + -- even if it's a fake + Nothing -> pprPanic "getInterfaceExports" (ppr mod_name) + } + where + doc_str = sep [ppr mod_name, ptext SLIT("is directly imported")] \end{code} @@ -527,45 +95,57 @@ getInterfaceExports mod_name from \begin{code} getImportedInstDecls :: NameSet -> RnMG [(Module,RdrNameHsDecl)] getImportedInstDecls gates - = -- First load any orphan-instance modules that aren't aready loaded + = -- First, load any orphan-instance modules that aren't aready loaded -- Orphan-instance modules are recorded in the module dependecnies - getIfacesRn `thenRn` \ ifaces -> + getIfacesRn `thenRn` \ ifaces -> let - orphan_mods = [mod | (mod, (_, True, Nothing)) <- fmToList (iImpModInfo ifaces)] + orphan_mods = + [mod | (mod, (True, _, False)) <- fmToList (iImpModInfo ifaces)] in - traceRn (text "Loading orphan modules" <+> fsep (map pprModuleName orphan_mods)) `thenRn_` - mapRn_ load_it orphan_mods `thenRn_` + loadOrphanModules orphan_mods `thenRn_` -- Now we're ready to grab the instance declarations -- Find the un-gated ones and return them, -- removing them from the bag kept in Ifaces - getIfacesRn `thenRn` \ ifaces -> + getIfacesRn `thenRn` \ ifaces -> let (decls, new_insts) = selectGated gates (iInsts ifaces) in setIfacesRn (ifaces { iInsts = new_insts }) `thenRn_` traceRn (sep [text "getImportedInstDecls:", - nest 4 (fsep (map ppr (nameSetToList gates))), - text "Slurped" <+> int (length decls) <+> text "instance declarations"]) `thenRn_` + nest 4 (fsep (map ppr gate_list)), + text "Slurped" <+> int (length decls) <+> text "instance declarations", + nest 4 (vcat (map ppr_brief_inst_decl decls))]) `thenRn_` returnRn decls where - load_it mod = loadInterface (doc_str mod) mod ImportBySystem - doc_str mod = sep [pprModuleName mod, ptext SLIT("is a orphan-instance module")] + gate_list = nameSetToList gates + +ppr_brief_inst_decl (mod, InstD (InstDecl inst_ty _ _ _ _)) + = case inst_ty of + HsForAllTy _ _ tau -> ppr tau + other -> ppr inst_ty getImportedRules :: RnMG [(Module,RdrNameHsDecl)] -getImportedRules +getImportedRules + | opt_IgnoreIfacePragmas = returnRn [] + | otherwise = getIfacesRn `thenRn` \ ifaces -> let gates = iSlurp ifaces -- Anything at all that's been slurped - (decls, new_rules) = selectGated gates (iRules ifaces) + rules = iRules ifaces + (decls, new_rules) = selectGated gates rules in - setIfacesRn (ifaces { iRules = new_rules }) `thenRn_` + if null decls then + returnRn [] + else + setIfacesRn (ifaces { iRules = new_rules }) `thenRn_` traceRn (sep [text "getImportedRules:", - text "Slurped" <+> int (length decls) <+> text "rules"]) `thenRn_` + text "Slurped" <+> int (length decls) <+> text "rules"]) `thenRn_` returnRn decls selectGated gates decl_bag + -- Select only those decls whose gates are *all* in 'gates' #ifdef DEBUG | opt_NoPruneDecls -- Just to try the effect of not gating at all = (foldrBag (\ (_,d) ds -> d:ds) [] decl_bag, emptyBag) -- Grab them all @@ -577,22 +157,6 @@ selectGated gates decl_bag select (reqd, decl) (yes, no) | isEmptyNameSet (reqd `minusNameSet` gates) = (decl:yes, no) | otherwise = (yes, (reqd,decl) `consBag` no) - -lookupFixity :: Name -> RnMS Fixity -lookupFixity name - | isLocallyDefined name - = getFixityEnv `thenRn` \ local_fix_env -> - case lookupNameEnv local_fix_env name of - Just (FixitySig _ fix _) -> returnRn fix - Nothing -> returnRn defaultFixity - - | otherwise -- Imported - = loadHomeInterface doc name `thenRn` \ (_, ifaces) -> - case lookupNameEnv (iFixes ifaces) name of - Just (FixitySig _ fix _) -> returnRn fix - Nothing -> returnRn defaultFixity - where - doc = ptext SLIT("Checking fixity for") <+> ppr name \end{code} @@ -602,290 +166,753 @@ lookupFixity name %* * %********************************************************* -getImportVersions figures out what the "usage information" for this moudule is; -that is, what it must record in its interface file as the things it uses. -It records: - - anything reachable from its body code - - any module exported with a "module Foo". +getImportVersions figures out what the ``usage information'' for this +moudule is; that is, what it must record in its interface file as the +things it uses. It records: -Why the latter? Because if Foo changes then this module's export list +\begin{itemize} +\item (a) anything reachable from its body code +\item (b) any module exported with a @module Foo@ +\item (c) anything reachable from an exported item +\end{itemize} + +Why (b)? Because if @Foo@ changes then this module's export list will change, so we must recompile this module at least as far as making a new interface file --- but in practice that means complete recompilation. -What about this? - module A( f, g ) where module B( f ) where - import B( f ) f = h 3 - g = ... h = ... - -Should we record B.f in A's usages? In fact we don't. Certainly, if -anything about B.f changes than anyone who imports A should be recompiled; -they'll get an early exit if they don't use B.f. However, even if B.f -doesn't change at all, B.h may do so, and this change may not be reflected -in f's version number. So there are two things going on when compiling module A: - -1. Are A.o and A.hi correct? Then we can bale out early. -2. Should modules that import A be recompiled? - -For (1) it is slightly harmful to record B.f in A's usages, because a change in -B.f's version will provoke full recompilation of A, producing an identical A.o, -and A.hi differing only in its usage-version of B.f (which isn't used by any importer). - -For (2), because of the tricky B.h question above, we ensure that A.hi is touched -(even if identical to its previous version) if A's recompilation was triggered by -an imported .hi file date change. Given that, there's no need to record B.f in -A's usages. - -On the other hand, if A exports "module B" then we *do* count module B among -A's usages, because we must recompile A to ensure that A.hi changes appropriately. +Why (c)? Consider this: +\begin{verbatim} + module A( f, g ) where | module B( f ) where + import B( f ) | f = h 3 + g = ... | h = ... +\end{verbatim} + +Here, @B.f@ isn't used in A. Should we nevertheless record @B.f@ in +@A@'s usages? Our idea is that we aren't going to touch A.hi if it is +*identical* to what it was before. If anything about @B.f@ changes +than anyone who imports @A@ should be recompiled in case they use +@B.f@ (they'll get an early exit if they don't). So, if anything +about @B.f@ changes we'd better make sure that something in A.hi +changes, and the convenient way to do that is to record the version +number @B.f@ in A.hi in the usage list. If B.f changes that'll force a +complete recompiation of A, which is overkill but it's the only way to +write a new, slightly different, A.hi. + +But the example is tricker. Even if @B.f@ doesn't change at all, +@B.h@ may do so, and this change may not be reflected in @f@'s version +number. But with -O, a module that imports A must be recompiled if +@B.h@ changes! So A must record a dependency on @B.h@. So we treat +the occurrence of @B.f@ in the export list *just as if* it were in the +code of A, and thereby haul in all the stuff reachable from it. + +[NB: If B was compiled with -O, but A isn't, we should really *still* +haul in all the unfoldings for B, in case the module that imports A *is* +compiled with -O. I think this is the case.] + +Even if B is used at all we get a usage line for B + import B :: ... ; +in A.hi, to record the fact that A does import B. This is used to decide +to look to look for B.hi rather than B.hi-boot when compiling a module that +imports A. This line says that A imports B, but uses nothing in it. +So we'll get an early bale-out when compiling A if B's version changes. \begin{code} -getImportVersions :: ModuleName -- Name of this module - -> Maybe [IE any] -- Export list for this module - -> RnMG (VersionInfo Name) -- Version info for these names +mkImportInfo :: ModuleName -- Name of this module + -> [ImportDecl n] -- The import decls + -> RnMG [ImportVersion Name] -getImportVersions this_mod exports +mkImportInfo this_mod imports = getIfacesRn `thenRn` \ ifaces -> + getHomeIfaceTableRn `thenRn` \ hit -> let + import_all_mods :: [ModuleName] + -- Modules where we imported all the names + -- (apart from hiding some, perhaps) + import_all_mods = nub [ m | ImportDecl m _ _ _ imp_list _ <- imports, + import_all imp_list ] + + import_all (Just (False, _)) = False -- Imports are specified explicitly + import_all other = True -- Everything is imported + mod_map = iImpModInfo ifaces imp_names = iVSlurp ifaces + pit = iPIT ifaces -- mv_map groups together all the things imported from a particular module. - mv_map1, mv_map2 :: FiniteMap ModuleName (WhatsImported Name) - - -- mv_map1 records all the modules that have a "module M" - -- in this module's export list with an "Everything" - mv_map1 = foldr add_mod emptyFM export_mods - - -- mv_map2 adds the version numbers of things exported individually - mv_map2 = foldr add_mv mv_map1 imp_names - - -- Build the result list by adding info for each module, - -- *omitting* (a) library modules - -- (b) source-imported modules - mk_version_info mod_name (version, has_orphans, cts) so_far - | omit cts = so_far -- Don't record usage info for this module - | otherwise = (mod_name, version, has_orphans, whats_imported) : so_far - where - whats_imported = case lookupFM mv_map2 mod_name of - Just wi -> wi - Nothing -> Specifically [] - - omit (Just (mod, boot_import, _)) = isLibModule mod || boot_import - omit Nothing = False + mv_map :: ModuleEnv [Name] + mv_map = foldr add_mv emptyModuleEnv imp_names + + add_mv name mv_map = addItem mv_map (nameModule name) name + + -- Build the result list by adding info for each module. + -- For (a) a library module, we don't record it at all unless it contains orphans + -- (We must never lose track of orphans.) + -- + -- (b) a source-imported module, don't record the dependency at all + -- + -- (b) may seem a bit strange. The idea is that the usages in a .hi file records + -- *all* the module's dependencies other than the loop-breakers. We use + -- this info in findAndReadInterface to decide whether to look for a .hi file or + -- a .hi-boot file. + -- + -- This means we won't track version changes, or orphans, from .hi-boot files. + -- The former is potentially rather bad news. It could be fixed by recording + -- whether something is a boot file along with the usage info for it, but + -- I can't be bothered just now. + + mk_imp_info mod_name (has_orphans, is_boot, opened) so_far + | mod_name == this_mod -- Check if M appears in the set of modules 'below' M + -- This seems like a convenient place to check + = WARN( not is_boot, ptext SLIT("Wierd:") <+> ppr this_mod <+> + ptext SLIT("imports itself (perhaps indirectly)") ) + so_far + + | not opened -- We didn't even open the interface + = -- This happens when a module, Foo, that we explicitly imported has + -- 'import Baz' in its interface file, recording that Baz is below + -- Foo in the module dependency hierarchy. We want to propagate this + -- information. The Nothing says that we didn't even open the interface + -- file but we must still propagate the dependency info. + -- The module in question must be a local module (in the same package) + go_for_it NothingAtAll + + + | is_lib_module && not has_orphans + = so_far + + | is_lib_module -- Record the module version only + = go_for_it (Everything module_vers) + + | otherwise + = go_for_it whats_imported + + where + go_for_it exports = (mod_name, has_orphans, is_boot, exports) : so_far + mod_iface = lookupTableByModName hit pit mod_name `orElse` panic "mkImportInfo" + mod = mi_module mod_iface + is_lib_module = not (isModuleInThisPackage mod) + version_info = mi_version mod_iface + version_env = vers_decls version_info + module_vers = vers_module version_info + + whats_imported = Specifically module_vers + export_vers import_items + (vers_rules version_info) + + import_items = [(n,v) | n <- lookupWithDefaultModuleEnv mv_map [] mod, + let v = lookupNameEnv version_env n `orElse` + pprPanic "mk_whats_imported" (ppr n) + ] + export_vers | moduleName mod `elem` import_all_mods + = Just (vers_exports version_info) + | otherwise + = Nothing + + import_info = foldFM mk_imp_info [] mod_map in - returnRn (foldFM mk_version_info [] mod_map) + traceRn (text "Modules in Ifaces: " <+> fsep (map ppr (keysFM mod_map))) `thenRn_` + returnRn import_info + + +addItem :: ModuleEnv [a] -> Module -> a -> ModuleEnv [a] +addItem fm mod x = extendModuleEnv_C add_item fm mod [x] + where + add_item xs _ = x:xs +\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` \ (decls, needed) -> + + -- Then get everything else + closeDecls decls needed `thenRn` \ decls1 -> + + -- Finally, get any deferred data type decls + slurpDeferredDecls decls1 `thenRn` \ final_decls -> + + returnRn final_decls + + +------------------------------------------------------- +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 - export_mods = case exports of - Nothing -> [] - Just es -> [mod | IEModuleContents mod <- es, mod /= this_mod] + -- 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_` + foldlRn 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) wanted_name + = importDecl wanted_name `thenRn` \ import_result -> + case import_result of + AlreadySlurped -> returnRn (decls, fvs, gates) + WiredIn -> returnRn (decls, fvs, gates `plusFV` getWiredInGates wanted_name) + Deferred -> returnRn (decls, fvs, gates `addOneFV` wanted_name) -- It's a type constructor + + HereItIs decl -> rnIfaceTyClDecl decl `thenRn` \ (new_decl, fvs1) -> + returnRn (TyClD new_decl : decls, + fvs1 `plusFV` fvs, + gates `plusFV` getGates source_fvs new_decl) + +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} - add_mv v@(name, version) mv_map - = addToFM_C add_item mv_map mod (Specifically [v]) - where - mod = moduleName (nameModule name) - add_item Everything _ = Everything - add_item (Specifically xs) _ = Specifically (v:xs) +\begin{code} +------------------------------------------------------- +-- 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 - add_mod mod mv_map = addToFM mv_map mod Everything + | 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 + + +------------------------------------------------------- +-- 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` \ import_result -> + case import_result of + -- Found a declaration... rename it + HereItIs decl -> rnIfaceTyClDecl decl `thenRn` \ (new_decl, fvs1) -> + returnRn (TyClD new_decl:decls, fvs1 `plusFV` fvs) + + -- No declaration... (wired in thing, or deferred, or already slurped) + other -> returnRn (decls, fvs) + + +------------------------------------------------------- +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) +rnIfaceTyClDecl (mod, decl) = initIfaceRnMS mod (rnTyClDecl decl) `thenRn` \ decl' -> + returnRn (decl', tyClDeclFVs decl') \end{code} + \begin{code} getSlurped = getIfacesRn `thenRn` \ ifaces -> returnRn (iSlurp ifaces) -recordSlurp maybe_version avail - = getIfacesRn `thenRn` \ ifaces@(Ifaces { iSlurp = slurped_names, - iVSlurp = imp_names }) -> - let +recordSlurp ifaces@(Ifaces { iSlurp = slurped_names, iVSlurp = imp_names }) + avail + = let new_slurped_names = addAvailToNameSet slurped_names avail + new_imp_names = availName avail : imp_names + in + ifaces { iSlurp = new_slurped_names, iVSlurp = new_imp_names } - new_imp_names = case maybe_version of - Just version -> (availName avail, version) : imp_names - Nothing -> imp_names +recordLocalSlurps local_avails + = getIfacesRn `thenRn` \ ifaces -> + let + new_slurped_names = foldl addAvailToNameSet (iSlurp ifaces) local_avails in - setIfacesRn (ifaces { iSlurp = new_slurped_names, - iVSlurp = new_imp_names }) + setIfacesRn (ifaces { iSlurp = new_slurped_names }) \end{code} + %********************************************************* -%* * -\subsection{Getting binders out of a declaration} -%* * +%* * +\subsection{Deferred declarations} +%* * %********************************************************* -@getDeclBinders@ returns the names for a @RdrNameHsDecl@. -It's used for both source code (from @availsFromDecl@) and interface files -(from @loadDecl@). - -It doesn't deal with source-code specific things: ValD, DefD. They -are handled by the sourc-code specific stuff in RnNames. +The idea of deferred declarations is this. Suppose we have a function + f :: T -> Int + data T = T1 A | T2 B + data A = A1 X | A2 Y + data B = B1 P | B2 Q +Then we don't want to load T and all its constructors, and all +the types those constructors refer to, and all the types *those* +constructors refer to, and so on. That might mean loading many more +interface files than is really necessary. So we 'defer' loading T. + +But f might be strict, and the calling convention for evaluating +values of type T depends on how many constructors T has, so +we do need to load T, but not the full details of the type T. +So we load the full decl for T, but only skeleton decls for A and B: + f :: T -> Int + data T = {- 2 constructors -} + +Whether all this is worth it is moot. \begin{code} -getDeclBinders :: (RdrName -> SrcLoc -> RnM d Name) -- New-name function - -> RdrNameHsDecl - -> RnM d (Maybe AvailInfo) +slurpDeferredDecls :: [RenamedHsDecl] -> RnMG [RenamedHsDecl] +slurpDeferredDecls decls = returnRn decls + +{- OMIT FOR NOW +slurpDeferredDecls :: [RenamedHsDecl] -> RnMG [RenamedHsDecl] +slurpDeferredDecls decls + = getDeferredDecls `thenRn` \ def_decls -> + rnIfaceDecls decls emptyFVs (map stripDecl def_decls) `thenRn` \ (decls1, fvs) -> + ASSERT( isEmptyFVs fvs ) + returnRn decls1 + +stripDecl (mod, TyClD (TyData dt _ tc tvs _ nconstrs _ loc name1 name2)) + = (mod, TyClD (TyData dt [] tc tvs [] nconstrs Nothing loc + name1 name2)) + -- Nuke the context and constructors + -- But retain the *number* of constructors! + -- Also the tvs will have kinds on them. +-} +\end{code} -getDeclBinders new_name (TyClD (TyData _ _ tycon _ condecls _ _ src_loc)) - = new_name tycon src_loc `thenRn` \ tycon_name -> - getConFieldNames new_name condecls `thenRn` \ sub_names -> - returnRn (Just (AvailTC tycon_name (tycon_name : nub sub_names))) - -- The "nub" is because getConFieldNames can legitimately return duplicates, - -- when a record declaration has the same field in multiple constructors -getDeclBinders new_name (TyClD (TySynonym tycon _ _ src_loc)) - = new_name tycon src_loc `thenRn` \ tycon_name -> - returnRn (Just (AvailTC tycon_name [tycon_name])) +%********************************************************* +%* * +\subsection{Extracting the `gates'} +%* * +%********************************************************* -getDeclBinders new_name (TyClD (ClassDecl _ cname _ sigs _ _ _ _ _ src_loc)) - = new_name cname src_loc `thenRn` \ class_name -> +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. - -- Record the names for the class ops - let - -- just want class-op sigs - op_sigs = filter isClassOpSig sigs - in - mapRn (getClassOpNames new_name) op_sigs `thenRn` \ sub_names -> +@getGates@ takes a newly imported (and renamed) decl, and the free +vars of the source program, and extracts from the decl the gate names. - returnRn (Just (AvailTC class_name (class_name : sub_names))) +\begin{code} +getGates source_fvs (IfaceSig _ ty _ _) + = extractHsTyNames ty + +getGates source_fvs (ClassDecl ctxt cls tvs _ sigs _ _ _ ) + = (delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) sigs) + (hsTyVarNames 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 (TySynonym tycon tvs ty _) + = delListFromNameSet (extractHsTyNames ty) + (hsTyVarNames tvs) + -- A type synonym type constructor isn't a "gate" for instance decls + +getGates source_fvs (TyData _ ctxt tycon tvs cons _ _ _ _ _) + = delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) cons) + (hsTyVarNames 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) + (hsTyVarNames 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 -getDeclBinders new_name (SigD (IfaceSig var ty prags src_loc)) - = new_name var src_loc `thenRn` \ var_name -> - returnRn (Just (Avail var_name)) + 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] -getDeclBinders new_name (FixD _) = returnRn Nothing -getDeclBinders new_name (ForD _) = returnRn Nothing -getDeclBinders new_name (DefD _) = returnRn Nothing -getDeclBinders new_name (InstD _) = returnRn Nothing -getDeclBinders new_name (RuleD _) = returnRn Nothing + get_field (fs,t) | any (`elemNameSet` source_fvs) fs = get_bang t + | otherwise = emptyFVs ----------------- -getConFieldNames new_name (ConDecl con _ _ (RecCon fielddecls) src_loc : rest) - = mapRn (\n -> new_name n src_loc) (con:fields) `thenRn` \ cfs -> - getConFieldNames new_name rest `thenRn` \ ns -> - returnRn (cfs ++ ns) - where - fields = concat (map fst fielddecls) + get_bang bty = extractHsTyNames (getBangType bty) +\end{code} -getConFieldNames new_name (ConDecl con _ _ condecl src_loc : rest) - = new_name con src_loc `thenRn` \ n -> - (case condecl of - NewCon _ (Just f) -> - new_name f src_loc `thenRn` \ new_f -> - returnRn [n,new_f] - _ -> returnRn [n]) `thenRn` \ nn -> - getConFieldNames new_name rest `thenRn` \ ns -> - returnRn (nn ++ ns) +@getWiredInGates@ is just like @getGates@, but it sees a wired-in @Name@ +rather than a declaration. -getConFieldNames new_name [] = returnRn [] +\begin{code} +getWiredInGates :: Name -> FreeVars +getWiredInGates name -- No classes are wired in + = case lookupNameEnv wiredInThingEnv name of + Just (AnId the_id) -> getWiredInGates_s (namesOfType (idType the_id)) -getClassOpNames new_name (ClassOpSig op _ _ src_loc) = new_name op src_loc -\end{code} + Just (ATyCon tc) + | isSynTyCon tc + -> getWiredInGates_s (delListFromNameSet (namesOfType ty) (map getName tyvars)) + where + (tyvars,ty) = getSynTyConDefn tc -@getDeclSysBinders@ gets the implicit binders introduced by a decl. -A the moment that's just the tycon and datacon that come with a class decl. -They aren'te returned by getDeclBinders because they aren't in scope; -but they *should* be put into the DeclsMap of this module. + other -> unitFV name -Note that this excludes the default-method names of a class decl, -and the dict fun of an instance decl, because both of these have -bindings of their own elsewhere. +getWiredInGates_s names = foldr (plusFV . getWiredInGates) emptyFVs (nameSetToList names) +\end{code} \begin{code} -getDeclSysBinders new_name (TyClD (ClassDecl _ cname _ sigs _ _ tname dname snames src_loc)) - = new_name dname src_loc `thenRn` \ datacon_name -> - new_name tname src_loc `thenRn` \ tycon_name -> - sequenceRn [new_name n src_loc | n <- snames] `thenRn` \ scsel_names -> - returnRn (tycon_name : datacon_name : scsel_names) - -getDeclSysBinders new_name other_decl - = returnRn [] +getInstDeclGates (InstD (InstDecl inst_ty _ _ _ _)) = extractHsTyNames inst_ty +getInstDeclGates other = emptyFVs \end{code} + %********************************************************* %* * -\subsection{Reading an interface file} +\subsection{Getting in a declaration} %* * %********************************************************* \begin{code} -findAndReadIface :: SDoc -> ModuleName -> WhereFrom - -> Bool -- Only relevant for SystemImport - -- True <=> Look for a .hi file - -- False <=> Look for .hi-boot file unless there's - -- a library .hi file - -> RnM d (Bool, Maybe (Module, ParsedIface)) - -- Bool is True if the interface actually read was a .hi-boot one - -- Nothing <=> file not found, or unreadable, or illegible - -- Just x <=> successfully found and parsed - -findAndReadIface doc_str mod_name from hi_file - = traceRn trace_msg `thenRn_` - -- we keep two maps for interface files, - -- one for 'normal' ones, the other for .hi-boot files, - -- hence the need to signal which kind we're interested. - - getHiMaps `thenRn` \ hi_maps -> - - case find_path from hi_maps of - -- Found the file - (hi_boot, Just (fpath, mod)) -> traceRn (ptext SLIT("...reading from") <+> text fpath) `thenRn_` - readIface mod fpath `thenRn` \ result -> - returnRn (hi_boot, result) - (hi_boot, Nothing) -> traceRn (ptext SLIT("...not found")) `thenRn_` - returnRn (hi_boot, Nothing) +importDecl :: Name -> RnMG ImportDeclResult + +data ImportDeclResult + = AlreadySlurped + | WiredIn + | Deferred + | HereItIs (Module, RdrNameTyClDecl) + +importDecl name + = -- Check if it was loaded before beginning this module + checkAlreadyAvailable name `thenRn` \ done -> + if done then + returnRn AlreadySlurped + else + + -- Check if we slurped it in while compiling this module + getIfacesRn `thenRn` \ ifaces -> + if name `elemNameSet` iSlurp ifaces then + returnRn AlreadySlurped + else + + -- Don't slurp in decls from this module's own interface file + -- (Indeed, this shouldn't happen.) + if isLocallyDefined name then + addWarnRn (importDeclWarn name) `thenRn_` + returnRn AlreadySlurped + else + + -- When we find a wired-in name we must load its home + -- module so that we find any instance decls lurking therein + if name `elemNameEnv` wiredInThingEnv then + loadHomeInterface doc name `thenRn_` + returnRn WiredIn + + else getNonWiredInDecl name where - find_path ImportByUser (hi_map, _) = (False, lookupFM hi_map mod_name) - find_path ImportByUserSource (_, hiboot_map) = (True, lookupFM hiboot_map mod_name) - - find_path ImportBySystem (hi_map, hiboot_map) - | hi_file - = -- If the module we seek is in our dependent set, - -- Look for a .hi file - (False, lookupFM hi_map mod_name) - - | otherwise - -- Check if there's a library module of that name - -- If not, look for an hi-boot file - = case lookupFM hi_map mod_name of - stuff@(Just (_, mod)) | isLibModule mod -> (False, stuff) - other -> (True, lookupFM hiboot_map mod_name) - - trace_msg = sep [hsep [ptext SLIT("Reading"), - ppr from, - ptext SLIT("interface for"), - pprModuleName mod_name <> semi], - nest 4 (ptext SLIT("reason:") <+> doc_str)] + doc = ptext SLIT("need home module for wired in thing") <+> ppr name + +getNonWiredInDecl :: Name -> RnMG ImportDeclResult +getNonWiredInDecl needed_name + = traceRn doc_str `thenRn_` + loadHomeInterface doc_str needed_name `thenRn` \ ifaces -> + case lookupNameEnv (iDecls ifaces) needed_name of + +{- OMIT DEFERRED STUFF FOR NOW, TILL GHCI WORKS + Just (version, avail, is_tycon_name, decl@(_, TyClD (TyData DataType _ _ _ _ ncons _ _ _ _))) + -- This case deals with deferred import of algebraic data types + + | not opt_NoPruneTyDecls + + && (opt_IgnoreIfacePragmas || ncons > 1) + -- We only defer if imported interface pragmas are ingored + -- or if it's not a product type. + -- Sole reason: The wrapper for a strict function may need to look + -- inside its arg, and hence need to see its arg type's constructors. + + && not (getUnique tycon_name `elem` cCallishTyKeys) + -- Never defer ccall types; we have to unbox them, + -- and importing them does no harm + + + -> -- OK, so we're importing a deferrable data type + if needed_name == tycon_name + -- The needed_name is the TyCon of a data type decl + -- Record that it's slurped, put it in the deferred set + -- and don't return a declaration at all + setIfacesRn (recordSlurp (ifaces {iDeferred = iDeferred ifaces + `addOneToNameSet` tycon_name}) + version (AvailTC needed_name [needed_name])) `thenRn_` + returnRn Deferred + + else + -- The needed name is a constructor of a data type decl, + -- getting a constructor, so remove the TyCon from the deferred set + -- (if it's there) and return the full declaration + setIfacesRn (recordSlurp (ifaces {iDeferred = iDeferred ifaces + `delFromNameSet` tycon_name}) + version avail) `thenRn_` + returnRn (HereItIs decl) + where + tycon_name = availName avail +-} + + Just (avail,_,decl) + -> setIfacesRn (recordSlurp ifaces avail) `thenRn_` + returnRn (HereItIs decl) + + Nothing + -> addErrRn (getDeclErr needed_name) `thenRn_` + returnRn AlreadySlurped + where + doc_str = ptext SLIT("need decl for") <+> ppr needed_name + +{- OMIT FOR NOW +getDeferredDecls :: RnMG [(Module, RdrNameHsDecl)] +getDeferredDecls + = getIfacesRn `thenRn` \ ifaces -> + let + decls_map = iDecls ifaces + deferred_names = nameSetToList (iDeferred ifaces) + get_abstract_decl n = case lookupNameEnv decls_map n of + Just (_, _, _, decl) -> decl + in + traceRn (sep [text "getDeferredDecls", nest 4 (fsep (map ppr deferred_names))]) `thenRn_` + returnRn (map get_abstract_decl deferred_names) +-} \end{code} -@readIface@ tries just the one file. +@getWiredInDecl@ maps a wired-in @Name@ to what it makes available. +It behaves exactly as if the wired in decl were actually in an interface file. +Specifically, +\begin{itemize} +\item if the wired-in name is a data type constructor or a data constructor, + it brings in the type constructor and all the data constructors; and + marks as ``occurrences'' any free vars of the data con. + +\item similarly for synonum type constructor + +\item if the wired-in name is another wired-in Id, it marks as ``occurrences'' + the free vars of the Id's type. + +\item it loads the interface file for the wired-in thing for the + sole purpose of making sure that its instance declarations are available +\end{itemize} +All this is necessary so that we know all types that are ``in play'', so +that we know just what instances to bring into scope. + + +%******************************************************** +%* * +\subsection{Checking usage information} +%* * +%******************************************************** + +@recompileRequired@ is called from the HscMain. It checks whether +a recompilation is required. It needs access to the persistent state, +finder, etc, because it may have to load lots of interface files to +check their versions. \begin{code} -readIface :: Module -> String -> RnM d (Maybe (Module, ParsedIface)) - -- Nothing <=> file not found, or unreadable, or illegible - -- Just x <=> successfully found and parsed -readIface the_mod file_path - = ioToRnM (hGetStringBuffer file_path) `thenRn` \ read_result -> - case read_result of - Right contents -> - case parseIface contents (mkSrcLoc (mkFastString file_path) 1) of - Failed err -> failWithRn Nothing err - Succeeded (PIface mod_nm iface) -> - warnCheckRn (mod_nm == moduleName the_mod) - (hsep [ ptext SLIT("Something is amiss; requested module name") - , pprModule the_mod - , ptext SLIT("differs from name found in the interface file ") - , pprModuleName mod_nm - ]) `thenRn_` - returnRn (Just (the_mod, iface)) - - Left err - | isDoesNotExistError err -> returnRn Nothing - | otherwise -> failWithRn Nothing (cannaeReadFile file_path err) +type RecompileRequired = Bool +upToDate = False -- Recompile not required +outOfDate = True -- Recompile required + +recompileRequired :: Module + -> Bool -- Source unchanged + -> Maybe ModIface -- Old interface, if any + -> RnMG RecompileRequired +recompileRequired mod source_unchanged maybe_iface + = traceRn (text "Considering whether compilation is required for" <+> ppr mod <> colon) `thenRn_` + + -- CHECK WHETHER THE SOURCE HAS CHANGED + if not source_unchanged then + traceRn (nest 4 (text "Source file changed or recompilation check turned off")) `thenRn_` + returnRn outOfDate + else + + -- CHECK WHETHER WE HAVE AN OLD IFACE + case maybe_iface of + Nothing -> traceRn (nest 4 (ptext SLIT("No old interface file"))) `thenRn_` + returnRn outOfDate ; + + Just iface -> -- Source code unchanged and no errors yet... carry on + checkList [checkModUsage u | u <- mi_usages iface] + +checkList :: [RnMG RecompileRequired] -> RnMG RecompileRequired +checkList [] = returnRn upToDate +checkList (check:checks) = check `thenRn` \ recompile -> + if recompile then + returnRn outOfDate + else + checkList checks \end{code} + +\begin{code} +checkModUsage :: ImportVersion Name -> RnMG RecompileRequired +-- Given the usage information extracted from the old +-- M.hi file for the module being compiled, figure out +-- whether M needs to be recompiled. + +checkModUsage (mod_name, _, _, NothingAtAll) + -- If CurrentModule.hi contains + -- import Foo :: ; + -- then that simply records that Foo lies below CurrentModule in the + -- hierarchy, but CurrentModule doesn't depend in any way on Foo. + -- In this case we don't even want to open Foo's interface. + = up_to_date (ptext SLIT("Nothing used from:") <+> ppr mod_name) + +checkModUsage (mod_name, _, _, whats_imported) + = tryLoadInterface doc_str mod_name ImportBySystem `thenRn` \ (ifaces, maybe_err) -> + case maybe_err of { + Just err -> out_of_date (sep [ptext SLIT("Can't find version number for module"), + ppr mod_name]) ; + -- Couldn't find or parse a module mentioned in the + -- old interface file. Don't complain -- it might just be that + -- the current module doesn't need that import and it's been deleted + + Nothing -> + + getHomeIfaceTableRn `thenRn` \ hit -> + let + mod_details = lookupTableByModName hit (iPIT ifaces) mod_name + `orElse` panic "checkModUsage" + new_vers = mi_version mod_details + new_decl_vers = vers_decls new_vers + in + case whats_imported of { -- NothingAtAll dealt with earlier + + Everything old_mod_vers -> checkModuleVersion old_mod_vers new_vers `thenRn` \ recompile -> + if recompile then + out_of_date (ptext SLIT("...and I needed the whole module")) + else + returnRn upToDate ; + + Specifically old_mod_vers maybe_old_export_vers old_decl_vers old_rule_vers -> + + -- CHECK MODULE + checkModuleVersion old_mod_vers new_vers `thenRn` \ recompile -> + if not recompile then + returnRn upToDate + else + + -- CHECK EXPORT LIST + if checkExportList maybe_old_export_vers new_vers then + out_of_date (ptext SLIT("Export list changed")) + else + + -- CHECK RULES + if old_rule_vers /= vers_rules new_vers then + out_of_date (ptext SLIT("Rules changed")) + else + + -- CHECK ITEMS ONE BY ONE + checkList [checkEntityUsage new_decl_vers u | u <- old_decl_vers] `thenRn` \ recompile -> + if recompile then + returnRn outOfDate -- This one failed, so just bail out now + else + up_to_date (ptext SLIT("...but the bits I use haven't.")) + + }} + where + doc_str = sep [ptext SLIT("need version info for"), ppr mod_name] + +------------------------ +checkModuleVersion old_mod_vers new_vers + | vers_module new_vers == old_mod_vers + = up_to_date (ptext SLIT("Module version unchanged")) + + | otherwise + = out_of_date (ptext SLIT("Module version has changed")) + +------------------------ +checkExportList Nothing new_vers = upToDate +checkExportList (Just v) new_vers = v /= vers_exports new_vers + +------------------------ +checkEntityUsage new_vers (name,old_vers) + = case lookupNameEnv new_vers name of + + Nothing -> -- We used it before, but it ain't there now + out_of_date (sep [ptext SLIT("No longer exported:"), ppr name]) + + Just new_vers -- It's there, but is it up to date? + | new_vers == old_vers -> returnRn upToDate + | otherwise -> out_of_date (sep [ptext SLIT("Out of date:"), ppr name]) + +up_to_date msg = traceRn msg `thenRn_` returnRn upToDate +out_of_date msg = traceRn msg `thenRn_` returnRn outOfDate +\end{code} + %********************************************************* %* * @@ -894,33 +921,16 @@ readIface the_mod file_path %********************************************************* \begin{code} -noIfaceErr filename boot_file - = hsep [ptext SLIT("Could not find valid"), boot, - ptext SLIT("interface file"), quotes (pprModule filename)] - where - boot | boot_file = ptext SLIT("[boot]") - | otherwise = empty - -cannaeReadFile file err - = hcat [ptext SLIT("Failed in reading file: "), - text file, - ptext SLIT("; error="), - text (show err)] - getDeclErr name - = ptext SLIT("Failed to find interface decl for") <+> quotes (ppr name) - -getDeclWarn name loc - = sep [ptext SLIT("Failed to find (optional) interface decl for") <+> quotes (ppr name), - ptext SLIT("desired at") <+> ppr loc] - -importDeclWarn mod name - = sep [ptext SLIT("Compiler tried to import decl from interface file with same name as module."), - ptext SLIT("(possible cause: module name clashes with interface file already in scope.)") + = vcat [ptext SLIT("Failed to find interface decl for") <+> quotes (ppr name), + ptext SLIT("from module") <+> quotes (ppr (nameModule name)) + ] + +importDeclWarn name + = sep [ptext SLIT( + "Compiler tried to import decl from interface file with same name as module."), + ptext SLIT( + "(possible cause: module name clashes with interface file already in scope.)") ] $$ - hsep [ptext SLIT("Interface:"), quotes (pprModuleName mod), - comma, ptext SLIT("name:"), quotes (ppr name)] - -warnRedundantSourceImport mod_name - = ptext SLIT("Unnecessary {- SOURCE -} in the import of module") <+> quotes (pprModuleName mod_name) + hsep [ptext SLIT("name:"), quotes (ppr name)] \end{code}