%
% (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,
-
- 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(..), InstDecl(..), HsType(..) )
-import HsImpExp ( ImportDecl(..) )
-import BasicTypes ( Version, defaultFixity )
-import RdrHsSyn ( RdrNameHsDecl, RdrNameTyClDecl, RdrNameInstDecl )
-import RnHiFiles ( tryLoadInterface, loadHomeInterface, loadInterface,
- loadOrphanModules
+import HsSyn ( HsDecl(..), Sig(..), TyClDecl(..), ConDecl(..), HsConDetails(..),
+ InstDecl(..), HsType(..), hsTyVarNames, getBangType
)
-import RnSource ( rnTyClDecl, rnDecl )
-import RnEnv
-import RnMonad
-import Name ( Name {-instance NamedThing-}, nameOccName,
- nameModule, isLocallyDefined,
- NamedThing(..),
- elemNameEnv
- )
-import Module ( Module, ModuleEnv,
- moduleName, isModuleInThisPackage,
- ModuleName, WhereFrom(..),
- emptyModuleEnv, lookupModuleEnvByName,
- extendModuleEnv_C, lookupWithDefaultModuleEnv
+import RdrHsSyn ( RdrNameTyClDecl, RdrNameInstDecl, RdrNameRuleDecl )
+import RnHsSyn ( RenamedHsDecl, RenamedTyClDecl,
+ extractHsTyNames, extractHsCtxtTyNames,
+ tyClDeclFVs, ruleDeclFVs, impDeclFVs
)
+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, dataConWrapId )
+import TyCon ( visibleDataCons, isSynTyCon, getSynTyConDefn, tyConClass_maybe, tyConName )
+import Class ( className, classSCTheta )
+import Name ( Name {-instance NamedThing-}, isWiredInName, nameIsLocalOrFrom,
+ nameModule, NamedThing(..) )
+import NameEnv ( delFromNameEnv, lookupNameEnv )
import NameSet
-import PrelInfo ( wiredInThingEnv )
-import Maybes ( orElse )
-import FiniteMap
+import Module ( Module, isHomeModule )
+import PrelNames ( hasKey, fractionalClassKey, numClassKey,
+ integerTyConName, doubleTyConName )
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 <n> :: ... ;
-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}
%* *
\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
-- 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)
+\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 (ADataCon dc) = tyConName (dataConTyCon dc)
+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
+ DataConWorkId dc -> get_main_name (ATyCon (dataConTyCon dc))
+ DataConWrapId dc -> get_main_name (ATyCon (dataConTyCon dc))
+ RecordSelId lbl -> get_main_name (ATyCon (fieldLabelTyCon lbl))
+ GenericOpId tc -> get_main_name (ATyCon tc)
+ ClassOpId cl -> className cl
+ 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 nameIsLocalOrFrom this_mod name 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}
%* *
%*********************************************************
+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
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
-
- other -> unitFV name
+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)
+
+getWiredInGates (AnId the_id) = tyClsNamesOfType (idType the_id)
+getWiredInGates (ADataCon dc) = tyClsNamesOfType (idType (dataConWrapId dc))
+ -- Should include classes in the 'stupid context' of the data con?
+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.
-
%********************************************************
%* *
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)
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}
= 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}
projects / ghc-hetmet.git / blobdiff