X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnIfaces.lhs;h=76dd8da573c052dfbb92757ada745224b014b92c;hb=0bffc410964e1688ad80d277d53400659e697ab5;hp=b7af688af7e8f47a2ff2001974d43fd12879590e;hpb=90fa6b84fdc99ba99c0b7df9691ca69d50b62530;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnIfaces.lhs b/ghc/compiler/rename/RnIfaces.lhs index b7af688..76dd8da 100644 --- a/ghc/compiler/rename/RnIfaces.lhs +++ b/ghc/compiler/rename/RnIfaces.lhs @@ -1,327 +1,54 @@ % % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998 -% -\section[RnIfaces]{Cacheing and Renaming of Interfaces} +section +\%[RnIfaces]{Cacheing and Renaming of Interfaces} \begin{code} module RnIfaces - ( - getInterfaceExports, - recordLocalSlurps, - mkImportInfo, - - slurpImpDecls, closeDecls, - - RecompileRequired, outOfDate, upToDate, recompileRequired + ( slurpImpDecls, importSupportingDecls, + RecompileRequired, outOfDate, upToDate, checkVersions ) where #include "HsVersions.h" -import CmdLineOpts ( DynFlags, opt_NoPruneDecls, opt_NoPruneTyDecls, opt_IgnoreIfacePragmas ) +import CmdLineOpts ( opt_IgnoreIfacePragmas, opt_NoPruneDecls ) import HscTypes -import HsSyn ( HsDecl(..), Sig(..), TyClDecl(..), ConDecl(..), ConDetails(..), +import HsSyn ( HsDecl(..), Sig(..), TyClDecl(..), ConDecl(..), HsConDetails(..), InstDecl(..), HsType(..), hsTyVarNames, getBangType ) -import HsImpExp ( ImportDecl(..) ) -import RdrHsSyn ( RdrNameHsDecl, RdrNameTyClDecl, RdrNameInstDecl ) -import RnHsSyn ( RenamedHsDecl, extractHsTyNames, extractHsCtxtTyNames, tyClDeclFVs ) -import RnHiFiles ( tryLoadInterface, loadHomeInterface, loadInterface, - loadOrphanModules +import RdrHsSyn ( RdrNameTyClDecl, RdrNameInstDecl, RdrNameRuleDecl ) +import RnHsSyn ( RenamedHsDecl, RenamedTyClDecl, + extractHsTyNames, extractHsCtxtTyNames, + tyClDeclFVs, ruleDeclFVs, impDeclFVs ) -import RnSource ( rnTyClDecl, rnDecl ) -import RnEnv -import RnMonad -import Id ( idType ) -import Type ( namesOfType ) -import TyCon ( isSynTyCon, getSynTyConDefn ) -import Name ( Name {-instance NamedThing-}, nameOccName, - nameModule, isLocallyDefined, nameUnique, - NamedThing(..), - elemNameEnv +import RnHiFiles ( loadInterface, loadHomeInterface, loadOrphanModules ) +import RnNames ( mkModDeps ) +import RnSource ( rnTyClDecl, rnInstDecl, rnIfaceRuleDecl ) +import TcEnv ( getInGlobalScope, tcLookupGlobal_maybe ) +import TcRnMonad +import Id ( idType, idName, globalIdDetails ) +import IdInfo ( GlobalIdDetails(..) ) +import TcType ( tyClsNamesOfType, classNamesOfTheta ) +import FieldLabel ( fieldLabelTyCon ) +import DataCon ( dataConTyCon ) +import TyCon ( visibleDataCons, isSynTyCon, getSynTyConDefn, tyConClass_maybe, tyConName ) +import Class ( className, classSCTheta ) +import Name ( Name {-instance NamedThing-}, isWiredInName, isInternalName, nameModule, NamedThing(..) ) -import Module ( Module, ModuleEnv, - moduleName, isModuleInThisPackage, - ModuleName, WhereFrom(..), - emptyModuleEnv, lookupModuleEnvByName, - extendModuleEnv_C, lookupWithDefaultModuleEnv - ) +import NameEnv ( delFromNameEnv, lookupNameEnv ) import NameSet -import PrelInfo ( wiredInThingEnv, fractionalClassKeys ) -import TysWiredIn ( doubleTyCon ) -import Maybes ( orElse ) +import Module ( Module, isHomeModule, extendModuleSet, moduleEnvElts ) +import PrelNames ( hasKey, fractionalClassKey, numClassKey, + integerTyConName, doubleTyConName ) import FiniteMap import Outputable import Bag - -import List ( nub ) -\end{code} - - -%********************************************************* -%* * -\subsection{Getting what a module exports} -%* * -%********************************************************* - -@getInterfaceExports@ is called only for directly-imported modules. - -\begin{code} -getInterfaceExports :: ModuleName -> WhereFrom -> RnMG (Module, Avails) -getInterfaceExports mod_name from - = 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} - - -%********************************************************* -%* * -\subsection{Instance declarations are handled specially} -%* * -%********************************************************* - -\begin{code} -getImportedInstDecls :: NameSet -> RnMG [(Module,RdrNameHsDecl)] -getImportedInstDecls gates - = -- First, load any orphan-instance modules that aren't aready loaded - -- Orphan-instance modules are recorded in the module dependecnies - getIfacesRn `thenRn` \ ifaces -> - let - orphan_mods = - [mod | (mod, (True, _, False)) <- fmToList (iImpModInfo ifaces)] - in - 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 -> - let - (decls, new_insts) = selectGated gates (iInsts ifaces) - in - setIfacesRn (ifaces { iInsts = new_insts }) `thenRn_` - - traceRn (sep [text "getImportedInstDecls:", - 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 - 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 - | opt_IgnoreIfacePragmas = returnRn [] - | otherwise - = getIfacesRn `thenRn` \ ifaces -> - let - gates = iSlurp ifaces -- Anything at all that's been slurped - rules = iRules ifaces - (decls, new_rules) = selectGated gates rules - in - if null decls then - returnRn [] - else - setIfacesRn (ifaces { iRules = new_rules }) `thenRn_` - traceRn (sep [text "getImportedRules:", - 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 - - | otherwise -#endif - = foldrBag select ([], emptyBag) decl_bag - where - select (reqd, decl) (yes, no) - | isEmptyNameSet (reqd `minusNameSet` gates) = (decl:yes, no) - | otherwise = (yes, (reqd,decl) `consBag` no) +import Maybe( fromJust ) \end{code} %********************************************************* -%* * -\subsection{Keeping track of what we've slurped, and version numbers} -%* * -%********************************************************* - -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: - -\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. - -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} -mkImportInfo :: ModuleName -- Name of this module - -> [ImportDecl n] -- The import decls - -> RnMG [ImportVersion Name] - -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_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 - 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} %* * @@ -329,34 +56,31 @@ addItem fm mod x = extendModuleEnv_C add_item fm mod [x] \begin{code} ------------------------------------------------------- +slurpImpDecls :: FreeVars -> TcRn m [RenamedHsDecl] slurpImpDecls source_fvs - = traceRn (text "slurpImp" <+> fsep (map ppr (nameSetToList source_fvs))) `thenRn_` + = traceRn (text "slurpImp" <+> fsep (map ppr (nameSetToList source_fvs))) `thenM_` - -- The current slurped-set records all local things - getSlurped `thenRn` \ source_binders -> - slurpSourceRefs source_binders source_fvs `thenRn` \ (decls, needed) -> + -- Slurp in things which might be 'gates' for instance + -- declarations, plus the instance declarations themselves + slurpSourceRefs source_fvs `thenM` \ (gate_decls, bndrs) -> -- Then get everything else - closeDecls decls needed `thenRn` \ decls1 -> - - -- Finally, get any deferred data type decls - slurpDeferredDecls decls1 `thenRn` \ final_decls -> - - returnRn final_decls + let + needed = foldr (plusFV . impDeclFVs) emptyFVs gate_decls + in + import_supporting_decls (gate_decls, bndrs) 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 +slurpSourceRefs :: FreeVars -- Variables referenced in source + -> TcRn m ([RenamedHsDecl], -- Needed declarations + NameSet) -- Names bound by those declarations +-- Slurp imported declarations needed directly by the source code; +-- and some of the ones they need. The goal is to find all the 'gates' +-- for instance declarations. + +slurpSourceRefs source_fvs + = go_outer [] emptyFVs -- Accumulating decls (nameSetToList source_fvs) -- Things whose defn hasn't been loaded yet where -- The outer loop repeatedly slurps the decls for the current gates @@ -364,170 +88,211 @@ slurpSourceRefs source_binders source_fvs -- 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. + -- 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 + -- 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 -> + go_outer decls bndrs [] = returnM (decls, bndrs) + + go_outer decls bndrs refs -- 'refs' are not necessarily slurped yet + = traceRn (text "go_outer" <+> ppr refs) `thenM_` + foldlM go_inner (decls, bndrs, emptyFVs) refs `thenM` \ (decls1, bndrs1, gates1) -> + getImportedInstDecls gates1 `thenM` \ (inst_decls, new_gates) -> + rnIfaceDecls rnInstDecl inst_decls `thenM` \ inst_decls' -> + go_outer (map InstD inst_decls' ++ decls1) + bndrs1 + (nameSetToList (new_gates `plusFV` plusFVs (map getInstDeclGates inst_decls'))) + -- NB: we go round again to fetch the decls for any gates of any decls + -- we have loaded. For example, if we mention + -- print :: Show a => a -> String + -- then we must load the decl for Show before stopping, to ensure + -- that instances from its home module are available + + go_inner (decls, bndrs, gates) wanted_name + = importDecl bndrs wanted_name `thenM` \ 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 + AlreadySlurped -> returnM (decls, bndrs, gates) + + InTypeEnv ty_thing + -> returnM (decls, + bndrs `addOneFV` wanted_name, -- Avoid repeated calls to getWiredInGates + gates `plusFV` getWiredInGates ty_thing) + + HereItIs decl new_bndrs + -> rnIfaceDecl rnTyClDecl decl `thenM` \ new_decl -> + returnM (TyClD new_decl : decls, + bndrs `plusFV` new_bndrs, + gates `plusFV` getGates source_fvs new_decl) \end{code} - \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 - - | otherwise - = getImportedRules `thenRn` \ rule_decls -> +-- import_supporting_decls keeps going until the free-var set is empty +importSupportingDecls needed + = import_supporting_decls ([], emptyNameSet) needed + +import_supporting_decls + :: ([RenamedHsDecl], NameSet) -- Some imported decls, with their binders + -> FreeVars -- Remaining un-slurped names + -> TcRn m [RenamedHsDecl] +import_supporting_decls decls needed + = slurpIfaceDecls decls needed `thenM` \ (decls1, bndrs1) -> + getImportedRules bndrs1 `thenM` \ 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 - + [] -> returnM decls1 -- No new rules, so we are done + other -> rnIfaceDecls rnIfaceRuleDecl rule_decls `thenM` \ rule_decls' -> + let + rule_fvs = plusFVs (map ruleDeclFVs rule_decls') + decls2 = decls1 ++ map RuleD rule_decls' + in + traceRn (text "closeRules" <+> ppr rule_decls' $$ + fsep (map ppr (nameSetToList rule_fvs))) `thenM_` + import_supporting_decls (decls2, bndrs1) rule_fvs + ------------------------------------------------------- --- 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) +-- Augment decls with any decls needed by needed, +-- and so on transitively +slurpIfaceDecls :: ([RenamedHsDecl], NameSet) -- Already slurped + -> FreeVars -- Still needed + -> TcRn m ([RenamedHsDecl], NameSet) +slurpIfaceDecls (decls, bndrs) needed + = slurp decls bndrs (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 + slurp decls bndrs [] = returnM (decls, bndrs) + slurp decls bndrs (n:ns) + = importDecl bndrs n `thenM` \ import_result -> + case import_result of + HereItIs decl new_bndrs -- Found a declaration... rename it + -> rnIfaceDecl rnTyClDecl decl `thenM` \ new_decl -> + slurp (TyClD new_decl : decls) + (bndrs `plusFV` new_bndrs) + (nameSetToList (tyClDeclFVs new_decl) ++ ns) + + + other -> -- No declaration... (wired in thing, or deferred, + -- or already slurped) + slurp decls (bndrs `addOneFV` n) ns ------------------------------------------------------- -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 rn decls = mappM (rnIfaceDecl rn) decls +rnIfaceDecl rn (mod, decl) = initRn (InterfaceMode mod) (rn decl) +\end{code} -------------------------------------------------------- -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') +\begin{code} + -- Tiresomely, we must get the "main" name for the + -- thing, because that's what VSlurp contains, and what + -- is recorded in the usage information +get_main_name (AClass cl) = className cl +get_main_name (ATyCon tc) + | Just clas <- tyConClass_maybe tc = get_main_name (AClass clas) + | otherwise = tyConName tc +get_main_name (AnId id) + = case globalIdDetails id of + DataConId dc -> get_main_name (ATyCon (dataConTyCon dc)) + DataConWrapId dc -> get_main_name (ATyCon (dataConTyCon dc)) + RecordSelId lbl -> get_main_name (ATyCon (fieldLabelTyCon lbl)) + other -> idName id + + +recordUsage :: Name -> TcRn m () +-- Record that the Name has been used, for +-- later generation of usage info in the interface file +recordUsage name = updUsages (upd_usg name) + +upd_usg name usages + | isHomeModule mod = addOneToNameSet usages name + | otherwise = usages + where + mod = nameModule name \end{code} +%********************************************************* +%* * +\subsection{Getting in a declaration} +%* * +%********************************************************* + \begin{code} -getSlurped - = getIfacesRn `thenRn` \ ifaces -> - returnRn (iSlurp ifaces) +importDecl :: NameSet -> Name -> TcRn m ImportDeclResult -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 } +data ImportDeclResult + = AlreadySlurped + | InTypeEnv TyThing + | HereItIs (Module, RdrNameTyClDecl) NameSet + -- The NameSet is the bunch of names bound by this decl + +importDecl already_slurped name + = -- STEP 0: Check if it's from this module + -- Doing this catches a common case quickly + getModule `thenM` \ this_mod -> + if isInternalName name || nameModule name == this_mod then + -- Variables defined on the GHCi command line (e.g. let x = 3) + -- are Internal names (which don't have a Module) + returnM AlreadySlurped + else -recordLocalSlurps local_avails - = getIfacesRn `thenRn` \ ifaces -> - let - new_slurped_names = foldl addAvailToNameSet (iSlurp ifaces) local_avails - in - setIfacesRn (ifaces { iSlurp = new_slurped_names }) -\end{code} + -- STEP 1: Check if we've slurped it in while compiling this module + if name `elemNameSet` already_slurped then + returnM AlreadySlurped + else + -- STEP 2: Check if it's already in the type environment + tcLookupGlobal_maybe name `thenM` \ maybe_thing -> + case maybe_thing of { + Just ty_thing + | isWiredInName name + -> -- When we find a wired-in name we must load its home + -- module so that we find any instance decls lurking therein + loadHomeInterface wi_doc name `thenM_` + returnM (InTypeEnv ty_thing) -%********************************************************* -%* * -\subsection{Deferred declarations} -%* * -%********************************************************* + | otherwise + -> -- We have slurp something that's already in the type environment, + -- that was not slurped in an earlier compilation. + -- Must still record it in the Usages info, because that's used to + -- generate usage information -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. + traceRn (text "not wired in" <+> ppr name) `thenM_` + recordUsage (get_main_name ty_thing) `thenM_` + returnM (InTypeEnv ty_thing) ; + + Nothing -> + + -- STEP 4: OK, we have to slurp it in from an interface file + -- First load the interface file + traceRn nd_doc `thenM_` + loadHomeInterface nd_doc name `thenM_` + + -- STEP 4: Get the declaration out + getEps `thenM` \ eps -> + let + (decls_map, n_slurped) = eps_decls eps + in + case lookupNameEnv decls_map name of + Just (avail,_,decl) -> setEps eps' `thenM_` + recordUsage (availName avail) `thenM_` + returnM (HereItIs decl (mkFVs avail_names)) + where + avail_names = availNames avail + new_decls_map = foldl delFromNameEnv decls_map avail_names + eps' = eps { eps_decls = (new_decls_map, n_slurped+1) } + + Nothing -> addErr (getDeclErr name) `thenM_` + returnM AlreadySlurped + } + where + wi_doc = ptext SLIT("need home module for wired in thing") <+> ppr name + nd_doc = ptext SLIT("need decl for") <+> ppr name -\begin{code} -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} @@ -537,61 +302,126 @@ stripDecl (mod, TyClD (TyData dt _ tc tvs _ nconstrs _ loc name1 name2)) %* * %********************************************************* +The gating story +~~~~~~~~~~~~~~~~~ +We want to avoid sucking in too many instance declarations. +An instance decl is only useful if the types and classes mentioned in +its 'head' are all available in the program being compiled. E.g. + + instance (..) => C (T1 a) (T2 b) where ... + +is only useful if C, T1 and T2 are all "available". So we keep +instance decls that have been parsed from .hi files, but not yet +slurped in, in a pool called the 'gated instance pool'. +Each has its set of 'gates': {C, T1, T2} in the above example. + +More precisely, the gates of a module are the types and classes +that are mentioned in: + + a) the source code [Note: in fact these don't seem + to be treated as gates, perhaps + because no imported instance decl + can mention them; mutter mutter + recursive modules.] + b) the type of an Id that's mentioned in the source code + [includes constructors and selectors] + c) the RHS of a type synonym that is a gate + d) the superclasses of a class that is a gate + e) the context of an instance decl that is slurped in + +We slurp in an instance decl from the gated instance pool iff + + all its gates are either in the gates of the module, + or the gates of a previously-loaded module + +The latter constraint is because there might have been an instance +decl slurped in during an earlier compilation, like this: + + instance Foo a => Baz (Maybe a) where ... + +In the module being compiled we might need (Baz (Maybe T)), where T is +defined in this module, and hence we need the instance for (Foo T). +So @Foo@ becomes a gate. But there's no way to 'see' that. More +generally, types might be involved as well: + + instance Foo2 S a => Baz2 a where ... + +Now we must treat S as a gate too, as well as Foo2. So the solution +we adopt is: + + we simply treat the gates of all previously-loaded + modules as gates of this one + +So the gates are remembered across invocations of the renamer in the +PersistentRenamerState. This gloss mainly affects ghc --make and ghc +--interactive. + +(We used to use the persistent type environment for this purpose, +but it has too much. For a start, it contains all tuple types, +because they are in the wired-in type env!) + + +Consructors and class operations +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 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. +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. + +And that's just what (b) says: we only treat T1's type as a gate if +T1 is mentioned. getGates, which deals with decls we are slurping in, +has to be a bit careful, because a mention of T1 will slurp in T's whole +declaration. + +----------------------------- @getGates@ takes a newly imported (and renamed) decl, and the free vars of the source program, and extracts from the decl the gate names. \begin{code} -getGates source_fvs (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 +getGates :: FreeVars -- Things mentioned in the source program + -- Used for the cunning "constructors and + -- class ops" story described 10 lines above. + -> RenamedTyClDecl + -> FreeVars + +getGates source_fvs decl + = get_gates (\n -> n `elemNameSet` source_fvs) decl + +get_gates is_used (ForeignType {tcdName = tycon}) = unitNameSet tycon +get_gates is_used (IfaceSig {tcdType = ty}) = extractHsTyNames ty + +get_gates is_used (ClassDecl { tcdCtxt = ctxt, tcdName = cls, tcdTyVars = tvs, tcdSigs = sigs}) + = (super_cls_and_sigs `addOneToNameSet` cls) `unionNameSets` + implicitClassGates cls where + super_cls_and_sigs = delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) sigs) + (hsTyVarNames tvs) 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) + | is_used n = extractHsTyNames ty + | otherwise = emptyFVs + +get_gates is_used (TySynonym {tcdTyVars = tvs, tcdSynRhs = 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) +get_gates is_used (TyData {tcdCtxt = ctxt, tcdName = tycon, tcdTyVars = tvs, tcdCons = cons}) + = delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) + (visibleDataCons cons)) (hsTyVarNames tvs) `addOneToNameSet` tycon where - get (ConDecl n _ tvs ctxt details _) - | n `elemNameSet` source_fvs + get (ConDecl n tvs ctxt details _) + | is_used n -- 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) _) + 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 @@ -600,176 +430,146 @@ getGates source_fvs (TyData _ ctxt tycon tvs cons _ _ _ _ _) get other_con = emptyFVs - get_details (VanillaCon tys) = plusFVs (map get_bang tys) + get_details (PrefixCon 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_field (fs,t) | any (`elemNameSet` source_fvs) fs = get_bang t - | otherwise = emptyFVs + get_field (f,t) | is_used f = get_bang t + | otherwise = emptyFVs get_bang bty = extractHsTyNames (getBangType bty) + +implicitClassGates :: Name -> FreeVars +implicitClassGates cls + -- If we load class Num, add Integer to the free gates + -- This takes account of the fact that Integer might be needed for + -- defaulting, but we don't want to load Integer (and all its baggage) + -- if there's no numeric stuff needed. + -- Similarly for class Fractional and Double + -- + -- NB: adding T to the gates will force T to be loaded + -- + -- NB: If we load (say) Floating, we'll end up loading Fractional too, + -- since Fractional is a superclass of Floating + | cls `hasKey` numClassKey = unitFV integerTyConName + | cls `hasKey` fractionalClassKey = unitFV doubleTyConName + | otherwise = emptyFVs \end{code} -@getWiredInGates@ is just like @getGates@, but it sees a wired-in @Name@ -rather than a declaration. +@getWiredInGates@ is just like @getGates@, but it sees a previously-loaded +thing rather than a declaration. \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)) - - Just (ATyCon tc) - | isSynTyCon tc - -> getWiredInGates_s (delListFromNameSet (namesOfType ty) (map getName tyvars)) - where - (tyvars,ty) = getSynTyConDefn tc +getWiredInGates :: TyThing -> FreeVars +-- The TyThing is one that we already have in our type environment, either +-- a) because the TyCon or Id is wired in, or +-- b) from a previous compile +-- +-- Either way, we might have instance decls in the (persistent) collection +-- of parsed-but-not-slurped instance decls that should be slurped in. +-- This might be the first module that mentions both the type and the class +-- for that instance decl, even though both the type and the class were +-- mentioned in other modules, and hence are in the type environment + +getWiredInGates (AClass cl) + = unitFV (getName cl) `plusFV` mkFVs super_classes + where + super_classes = classNamesOfTheta (classSCTheta cl) - other -> unitFV name +getWiredInGates (AnId the_id) = tyClsNamesOfType (idType the_id) +getWiredInGates (ATyCon tc) + | isSynTyCon tc = tyClsNamesOfType ty + | otherwise = unitFV (getName tc) + where + (_,ty) = getSynTyConDefn tc -getWiredInGates_s names = foldr (plusFV . getWiredInGates) emptyFVs (nameSetToList names) +getInstDeclGates (InstDecl inst_ty _ _ _ _) = extractHsTyNames inst_ty \end{code} \begin{code} -getInstDeclGates (InstD (InstDecl inst_ty _ _ _ _)) = extractHsTyNames inst_ty -getInstDeclGates other = emptyFVs -\end{code} - +getImportedInstDecls :: NameSet -> TcRn m ([(Module,RdrNameInstDecl)], NameSet) + -- Returns the gates that are new since last time +getImportedInstDecls gates + = -- First, load any orphan-instance modules that aren't aready loaded + -- Orphan-instance modules are recorded in the module dependecnies + getImports `thenM` \ imports -> + getEps `thenM` \ eps -> + let + old_gates = eps_inst_gates eps + new_gates = gates `minusNameSet` old_gates + all_gates = new_gates `unionNameSets` old_gates + orphan_mods = imp_orphs imports + in + loadOrphanModules orphan_mods `thenM_` -%********************************************************* -%* * -\subsection{Getting in a declaration} -%* * -%********************************************************* + -- Now we're ready to grab the instance declarations + -- Find the un-gated ones and return them, + -- removing them from the bag kept in EPS + -- Don't foget to get the EPS a second time... + -- loadOrphanModules may have side-effected it! + getEps `thenM` \ eps -> + let + available n = n `elemNameSet` all_gates + (decls, new_insts) = selectGated available (eps_insts eps) + in + setEps (eps { eps_insts = new_insts, + eps_inst_gates = all_gates }) `thenM_` -\begin{code} -importDecl :: Name -> RnMG ImportDeclResult + traceRn (sep [text "getImportedInstDecls:", + nest 4 (fsep (map ppr (nameSetToList gates))), + nest 4 (fsep (map ppr (nameSetToList all_gates))), + nest 4 (fsep (map ppr (nameSetToList new_gates))), + text "Slurped" <+> int (length decls) <+> text "instance declarations", + nest 4 (vcat (map ppr_brief_inst_decl decls))]) `thenM_` + returnM (decls, new_gates) -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 +ppr_brief_inst_decl (mod, InstDecl inst_ty _ _ _ _) + = case inst_ty of + HsForAllTy _ _ tau -> ppr tau + other -> ppr inst_ty - -- 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 +getImportedRules :: NameSet -- Slurped already + -> TcRn m [(Module,RdrNameRuleDecl)] +getImportedRules slurped + | opt_IgnoreIfacePragmas = returnM [] + | otherwise + = getEps `thenM` \ eps -> + getInGlobalScope `thenM` \ in_type_env -> + let + -- Slurp rules for anything that is slurped, + -- either now, or previously + available n = n `elemNameSet` slurped || in_type_env n + (decls, new_rules) = selectGated available (eps_rules eps) + in + if null decls then + returnM [] else + setEps (eps { eps_rules = new_rules }) `thenM_` + traceRn (sep [text "getImportedRules:", + text "Slurped" <+> int (length decls) <+> text "rules"]) `thenM_` + returnM decls - -- 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 - 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) +selectGated :: (Name->Bool) -> GatedDecls d + -> ([(Module,d)], GatedDecls d) +selectGated available (decl_bag, n_slurped) + -- Select only those decls whose gates are *all* available +#ifdef DEBUG + | opt_NoPruneDecls -- Just to try the effect of not gating at all + = let + decls = foldrBag (\ (_,d) ds -> d:ds) [] decl_bag -- Grab them all + in + (decls, (emptyBag, n_slurped + length decls)) - Nothing - -> addErrRn (getDeclErr needed_name) `thenRn_` - returnRn AlreadySlurped + | otherwise +#endif + = case foldrBag select ([], emptyBag) decl_bag of + (decls, new_bag) -> (decls, (new_bag, n_slurped + length decls)) 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) --} + select (gate_fn, decl) (yes, no) + | gate_fn available = (decl:yes, no) + | otherwise = (yes, (gate_fn,decl) `consBag` no) \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, -\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. - %******************************************************** %* * @@ -787,116 +587,112 @@ 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 ; +checkVersions :: Bool -- True <=> source unchanged + -> ModIface -- Old interface + -> TcRn m RecompileRequired +checkVersions source_unchanged iface + | not source_unchanged + = returnM outOfDate + | otherwise + = traceHiDiffs (text "Considering whether compilation is required for" <+> + ppr (mi_module iface) <> colon) `thenM_` + + -- Source code unchanged and no errors yet... carry on + -- First put the dependent-module info in the envt, just temporarily, + -- so that when we look for interfaces we look for the right one (.hi or .hi-boot) + -- It's just temporary because either the usage check will succeed + -- (in which case we are done with this module) or it'll fail (in which + -- case we'll compile the module from scratch anyhow). + updGblEnv (\ gbl -> gbl { tcg_imports = mod_deps }) ( + checkList [checkModUsage u | u <- mi_usages iface] + ) - Just iface -> -- Source code unchanged and no errors yet... carry on - checkList [checkModUsage u | u <- mi_usages iface] + where + -- This is a bit of a hack really + mod_deps = emptyImportAvails { imp_dep_mods = mkModDeps (dep_mods (mi_deps iface)) } -checkList :: [RnMG RecompileRequired] -> RnMG RecompileRequired -checkList [] = returnRn upToDate -checkList (check:checks) = check `thenRn` \ recompile -> +checkList :: [TcRn m RecompileRequired] -> TcRn m RecompileRequired +checkList [] = returnM upToDate +checkList (check:checks) = check `thenM` \ recompile -> if recompile then - returnRn outOfDate + returnM outOfDate else checkList checks \end{code} \begin{code} -checkModUsage :: ImportVersion Name -> RnMG RecompileRequired +checkModUsage :: Usage Name -> TcRn m 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]) ; +checkModUsage (Usage { usg_name = mod_name, usg_mod = old_mod_vers, + usg_rules = old_rule_vers, + usg_exports = maybe_old_export_vers, + usg_entities = old_decl_vers }) + = -- Load the imported interface is possible + let + doc_str = sep [ptext SLIT("need version info for"), ppr mod_name] + in + traceHiDiffs (text "Checking usages for module" <+> ppr mod_name) `thenM_` + + tryM (loadInterface doc_str mod_name ImportBySystem) `thenM` \ mb_iface -> + + case mb_iface of { + Left exn -> (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 -> + Right iface -> 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 + new_vers = mi_version iface + new_mod_vers = vers_module new_vers + new_decl_vers = vers_decls new_vers + new_export_vers = vers_exports new_vers + new_rule_vers = vers_rules 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 -> + checkModuleVersion old_mod_vers new_mod_vers `thenM` \ recompile -> if not recompile then - returnRn upToDate + returnM upToDate else -- CHECK EXPORT LIST - if checkExportList maybe_old_export_vers new_vers then - out_of_date (ptext SLIT("Export list changed")) + if checkExportList maybe_old_export_vers new_export_vers then + out_of_date_vers (ptext SLIT(" Export list changed")) + (fromJust maybe_old_export_vers) + new_export_vers else -- CHECK RULES - if old_rule_vers /= vers_rules new_vers then - out_of_date (ptext SLIT("Rules changed")) + if old_rule_vers /= new_rule_vers then + out_of_date_vers (ptext SLIT(" Rules changed")) + old_rule_vers new_rule_vers else -- CHECK ITEMS ONE BY ONE - checkList [checkEntityUsage new_decl_vers u | u <- old_decl_vers] `thenRn` \ recompile -> + checkList [checkEntityUsage new_decl_vers u | u <- old_decl_vers] `thenM` \ recompile -> if recompile then - returnRn outOfDate -- This one failed, so just bail out now + returnM outOfDate -- This one failed, so just bail out now else - up_to_date (ptext SLIT("...but the bits I use haven't.")) + up_to_date (ptext SLIT(" Great! The bits I use are up to date")) - }} - 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 +checkModuleVersion old_mod_vers new_mod_vers + | new_mod_vers == old_mod_vers = up_to_date (ptext SLIT("Module version unchanged")) | otherwise - = out_of_date (ptext SLIT("Module version has changed")) + = out_of_date_vers (ptext SLIT(" Module version has changed")) + old_mod_vers new_mod_vers ------------------------ checkExportList Nothing new_vers = upToDate -checkExportList (Just v) new_vers = v /= vers_exports new_vers +checkExportList (Just v) new_vers = v /= new_vers ------------------------ checkEntityUsage new_vers (name,old_vers) @@ -906,11 +702,15 @@ checkEntityUsage new_vers (name,old_vers) 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 + | new_vers == old_vers -> traceHiDiffs (text " Up to date" <+> ppr name <+> parens (ppr new_vers)) `thenM_` + returnM upToDate + | otherwise -> out_of_date_vers (ptext SLIT(" Out of date:") <+> ppr name) + old_vers new_vers + +up_to_date msg = traceHiDiffs msg `thenM_` returnM upToDate +out_of_date msg = traceHiDiffs msg `thenM_` returnM outOfDate +out_of_date_vers msg old_vers new_vers + = out_of_date (hsep [msg, ppr old_vers, ptext SLIT("->"), ppr new_vers]) \end{code} @@ -925,12 +725,4 @@ getDeclErr name = 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("name:"), quotes (ppr name)] \end{code}