2 % (c) The GRASP/AQUA Project, Glasgow University, 1993-1998
4 \section[MkIface]{Print an interface for a module}
13 #include "HsVersions.h"
15 import IO ( Handle, hPutStr, openFile,
16 hClose, hPutStrLn, IOMode(..) )
19 import BasicTypes ( Fixity(..), FixityDirection(..), NewOrData(..),
23 import RnEnv ( availName )
25 import TcInstUtil ( InstInfo(..) )
26 import WorkWrap ( getWorkerIdAndCons )
29 import Id ( Id, idType, idInfo, omitIfaceSigForId,
34 import DataCon ( dataConSig, dataConFieldLabels, dataConStrictMarks )
35 import IdInfo ( IdInfo, StrictnessInfo, ArityInfo, InlinePragInfo(..), inlinePragInfo,
36 arityInfo, ppArityInfo,
37 strictnessInfo, ppStrictnessInfo,
40 workerExists, workerInfo, isBottomingStrictness
42 import CoreSyn ( CoreExpr, CoreBind, Bind(..) )
43 import CoreUtils ( exprSomeFreeVars )
44 import CoreUnfold ( calcUnfoldingGuidance, UnfoldingGuidance(..),
45 Unfolding, okToUnfoldInHiFile )
46 import Module ( moduleString, pprModule, pprModuleBoot )
47 import Name ( isLocallyDefined, isWiredInName, nameRdrName, nameModule,
51 import OccName ( OccName, pprOccName )
52 import TyCon ( TyCon, getSynTyConDefn, isSynTyCon, isNewTyCon, isAlgTyCon,
53 tyConTheta, tyConTyVars, tyConDataCons
55 import Class ( Class, classBigSig )
56 import SpecEnv ( specEnvToList )
57 import FieldLabel ( fieldLabelName, fieldLabelType )
58 import Type ( mkSigmaTy, splitSigmaTy, mkDictTy, tidyTopType, deNoteType,
63 import PprCore ( pprIfaceUnfolding )
65 import Bag ( bagToList, isEmptyBag )
66 import Maybes ( catMaybes, maybeToBool )
67 import FiniteMap ( emptyFM, addToFM, addToFM_C, fmToList, FiniteMap )
68 import UniqFM ( lookupUFM, listToUFM )
69 import UniqSet ( uniqSetToList )
70 import Util ( sortLt, mapAccumL )
74 We have a function @startIface@ to open the output file and put
75 (something like) ``interface Foo'' in it. It gives back a handle
76 for subsequent additions to the interface file.
78 We then have one-function-per-block-of-interface-stuff, e.g.,
79 @ifaceExportList@ produces the @__exports__@ section; it appends
80 to the handle provided by @startIface@.
84 -> IO (Maybe Handle) -- Nothing <=> don't do an interface
86 ifaceMain :: Maybe Handle
91 ifaceDecls :: Maybe Handle
94 -> [Id] -- Ids used at code-gen time; they have better pragma info!
95 -> [CoreBind] -- In dependency order, later depend on earlier
98 endIface :: Maybe Handle -> IO ()
103 = case opt_ProduceHi of
104 Nothing -> return Nothing -- not producing any .hi file
106 if_hdl <- openFile fn WriteMode
107 hPutStr if_hdl ("__interface " ++ moduleString mod ++ ' ':show (opt_HiVersion :: Int))
108 hPutStrLn if_hdl " where"
111 endIface Nothing = return ()
112 endIface (Just if_hdl) = hPutStr if_hdl "\n" >> hClose if_hdl
117 ifaceMain Nothing iface_stuff = return ()
118 ifaceMain (Just if_hdl)
119 (import_usages, ExportEnv avails fixities, instance_modules)
121 ifaceImports if_hdl import_usages
122 ifaceInstanceModules if_hdl instance_modules
123 ifaceExports if_hdl avails
124 ifaceFixities if_hdl fixities
127 ifaceDecls Nothing tycons classes inst_info final_ids simplified = return ()
128 ifaceDecls (Just hdl)
132 | null_decls = return ()
133 -- You could have a module with just (re-)exports/instances in it
135 = ifaceClasses hdl classes >>
136 ifaceInstances hdl inst_infos >>= \ needed_ids ->
137 ifaceTyCons hdl tycons >>
138 ifaceBinds hdl needed_ids final_ids binds >>
141 null_decls = null binds &&
144 isEmptyBag inst_infos
148 ifaceImports if_hdl import_usages
149 = hPutCol if_hdl upp_uses (sortLt lt_imp_vers import_usages)
151 upp_uses (m, mv, whats_imported)
152 = ptext SLIT("import ") <>
153 hsep [pprModule m, pprModuleBoot m, int mv, dcolon,
154 upp_import_versions whats_imported
157 -- Importing the whole module is indicated by an empty list
158 upp_import_versions Everything = empty
160 -- For imported versions we do print the version number
161 upp_import_versions (Specifically nvs)
162 = hsep [ hsep [ppr_unqual_name n, int v] | (n,v) <- sort_versions nvs ]
164 ifaceInstanceModules if_hdl [] = return ()
165 ifaceInstanceModules if_hdl imods
166 = let sorted = sortLt (<) imods
167 lines = map (\m -> ptext SLIT("__instimport ") <> pprModule m <>
168 ptext SLIT(" ;")) sorted
170 printForIface if_hdl (vcat lines) >>
173 ifaceExports if_hdl [] = return ()
174 ifaceExports if_hdl avails
175 = hPutCol if_hdl do_one_module (fmToList export_fm)
177 -- Sort them into groups by module
178 export_fm :: FiniteMap Module [AvailInfo]
179 export_fm = foldr insert emptyFM avails
181 insert avail efm = addToFM_C (++) efm mod [avail]
183 mod = nameModule (availName avail)
185 -- Print one module's worth of stuff
186 do_one_module :: (Module, [AvailInfo]) -> SDoc
187 do_one_module (mod_name, avails@(avail1:_))
188 = ptext SLIT("__export ") <>
189 hsep [pprModuleBoot (nameModule (availName avail1)),
191 hsep (map upp_avail (sortLt lt_avail avails))
194 ifaceFixities if_hdl [] = return ()
195 ifaceFixities if_hdl fixities
196 = hPutCol if_hdl upp_fixity fixities
199 %************************************************************************
201 \subsection{Instance declarations}
203 %************************************************************************
207 ifaceInstances :: Handle -> Bag InstInfo -> IO IdSet -- The IdSet is the needed dfuns
208 ifaceInstances if_hdl inst_infos
209 | null togo_insts = return emptyVarSet
210 | otherwise = hPutCol if_hdl pp_inst (sortLt lt_inst togo_insts) >>
213 togo_insts = filter is_togo_inst (bagToList inst_infos)
214 needed_ids = mkVarSet [dfun_id | InstInfo _ _ _ _ dfun_id _ _ _ <- togo_insts]
215 is_togo_inst (InstInfo _ _ _ _ dfun_id _ _ _) = isLocallyDefined dfun_id
218 lt_inst (InstInfo _ _ _ _ dfun_id1 _ _ _)
219 (InstInfo _ _ _ _ dfun_id2 _ _ _)
220 = getOccName dfun_id1 < getOccName dfun_id2
221 -- The dfuns are assigned names df1, df2, etc, in order of original textual
222 -- occurrence, and this makes as good a sort order as any
225 pp_inst (InstInfo clas tvs tys theta dfun_id _ _ _)
227 -- The deNoteType is very important. It removes all type
228 -- synonyms from the instance type in interface files.
229 -- That in turn makes sure that when reading in instance decls
230 -- from interface files that the 'gating' mechanism works properly.
231 -- Otherwise you could have
232 -- type Tibble = T Int
233 -- instance Foo Tibble where ...
234 -- and this instance decl wouldn't get imported into a module
235 -- that mentioned T but not Tibble.
236 forall_ty = mkSigmaTy tvs theta (deNoteType (mkDictTy clas tys))
237 renumbered_ty = tidyTopType forall_ty
239 hcat [ptext SLIT("instance "), pprType renumbered_ty,
240 ptext SLIT(" = "), ppr_unqual_name dfun_id, semi]
244 %************************************************************************
246 \subsection{Printing values}
248 %************************************************************************
251 ifaceId :: (Id -> IdInfo) -- This function "knows" the extra info added
252 -- by the STG passes. Sigh
254 -> IdSet -- Set of Ids that are needed by earlier interface
255 -- file emissions. If the Id isn't in this set, and isn't
256 -- exported, there's no need to emit anything
257 -> Bool -- True <=> recursive, so don't print unfolding
259 -> CoreExpr -- The Id's right hand side
260 -> Maybe (SDoc, IdSet) -- The emitted stuff, plus a possibly-augmented set of needed Ids
262 ifaceId get_idinfo needed_ids is_rec id rhs
263 | not (id `elemVarSet` needed_ids || -- Needed [no id in needed_ids has omitIfaceSigForId]
264 (isExported id && not (omitIfaceSigForId id))) -- or exported and not to be omitted
265 = Nothing -- Well, that was easy!
267 ifaceId get_idinfo needed_ids is_rec id rhs
268 = Just (hsep [sig_pretty, prag_pretty, char ';'], new_needed_ids)
270 idinfo = get_idinfo id
271 inline_pragma = inlinePragInfo idinfo
273 ty_pretty = pprType (idType id)
274 sig_pretty = hsep [ppr (getOccName id), dcolon, ty_pretty]
277 | opt_OmitInterfacePragmas = empty
278 | otherwise = hsep [ptext SLIT("{-##"),
287 ------------ Arity --------------
288 arity_pretty = ppArityInfo (arityInfo idinfo)
290 ------------ Caf Info --------------
291 caf_pretty = ppCafInfo (cafInfo idinfo)
293 ------------ CPR Info --------------
294 cpr_pretty = ppCprInfo (cprInfo idinfo)
296 ------------ Strictness and Worker --------------
297 strict_info = strictnessInfo idinfo
298 work_info = workerInfo idinfo
299 has_worker = workerExists work_info
300 bottoming_fn = isBottomingStrictness strict_info
301 strict_pretty = ppStrictnessInfo strict_info <+> wrkr_pretty
303 wrkr_pretty | not has_worker = empty
304 | null con_list = ppr work_id
305 | otherwise = ppr work_id <+>
306 braces (hsep (map ppr con_list))
308 (Just work_id) = work_info
309 wrapper_cons = snd $ getWorkerIdAndCons id rhs
310 con_list = uniqSetToList wrapper_cons
312 ------------ Unfolding --------------
313 unfold_pretty | show_unfold = unfold_herald <+> pprIfaceUnfolding rhs
316 show_unfold = not has_worker && -- Not unnecessary
317 not bottoming_fn && -- Not necessary
318 unfolding_needed -- Not dangerous
320 unfolding_needed = case inline_pragma of
321 IMustBeINLINEd -> definitely_ok_to_unfold
322 IWantToBeINLINEd -> definitely_ok_to_unfold
323 NoInlinePragInfo -> rhs_is_small
327 unfold_herald = case inline_pragma of
328 NoInlinePragInfo -> ptext SLIT("__u")
329 other -> ppr inline_pragma
331 rhs_is_small = case calcUnfoldingGuidance opt_InterfaceUnfoldThreshold rhs of
332 UnfoldNever -> False -- Too big
333 other -> definitely_ok_to_unfold -- Small enough
335 definitely_ok_to_unfold = okToUnfoldInHiFile rhs
337 ------------ Specialisations --------------
338 spec_list = specEnvToList (getIdSpecialisation id)
339 spec_pretty = hsep (map pp_spec spec_list)
340 pp_spec (tyvars, tys, rhs) = hsep [ptext SLIT("__P"),
341 if null tyvars then ptext SLIT("[ ]")
342 else brackets (interppSP tyvars),
343 -- The lexer interprets "[]" as a CONID. Sigh.
344 hsep (map pprParendType tys),
346 pprIfaceUnfolding rhs
349 ------------ Extra free Ids --------------
350 new_needed_ids = (needed_ids `minusVarSet` unitVarSet id) `unionVarSet`
353 extra_ids | opt_OmitInterfacePragmas = emptyVarSet
354 | otherwise = worker_ids `unionVarSet`
355 unfold_ids `unionVarSet`
358 worker_ids | has_worker && interesting work_id = unitVarSet work_id
359 -- Conceivably, the worker might come from
361 | otherwise = emptyVarSet
363 spec_ids = foldr add emptyVarSet spec_list
365 add (_, _, rhs) = unionVarSet (find_fvs rhs)
367 unfold_ids | show_unfold = find_fvs rhs
368 | otherwise = emptyVarSet
370 find_fvs expr = free_vars
372 free_vars = exprSomeFreeVars interesting expr
374 interesting id = isId id && isLocallyDefined id &&
375 not (omitIfaceSigForId id)
380 -> IdSet -- These Ids are needed already
381 -> [Id] -- Ids used at code-gen time; they have better pragma info!
382 -> [CoreBind] -- In dependency order, later depend on earlier
385 ifaceBinds hdl needed_ids final_ids binds
386 = mapIO (printForIface hdl) pretties >>
389 final_id_map = listToUFM [(id,id) | id <- final_ids]
390 get_idinfo id = case lookupUFM final_id_map id of
391 Just id' -> idInfo id'
392 Nothing -> pprTrace "ifaceBinds not found:" (ppr id) $
395 pretties = go needed_ids (reverse binds) -- Reverse so that later things will
396 -- provoke earlier ones to be emitted
397 go needed [] = if not (isEmptyVarSet needed) then
398 pprTrace "ifaceBinds: free vars:"
399 (sep (map ppr (varSetElems needed))) $
404 go needed (NonRec id rhs : binds)
405 = case ifaceId get_idinfo needed False id rhs of
406 Nothing -> go needed binds
407 Just (pretty, needed') -> pretty : go needed' binds
409 -- Recursive groups are a bit more of a pain. We may only need one to
410 -- start with, but it may call out the next one, and so on. So we
411 -- have to look for a fixed point.
412 go needed (Rec pairs : binds)
413 = pretties ++ go needed'' binds
415 (needed', pretties) = go_rec needed pairs
416 needed'' = needed' `minusVarSet` mkVarSet (map fst pairs)
417 -- Later ones may spuriously cause earlier ones to be "needed" again
419 go_rec :: IdSet -> [(Id,CoreExpr)] -> (IdSet, [SDoc])
421 | null pretties = (needed, [])
422 | otherwise = (final_needed, more_pretties ++ pretties)
424 reduced_pairs = [pair | (pair,Nothing) <- pairs `zip` maybes]
425 pretties = catMaybes maybes
426 (needed', maybes) = mapAccumL do_one needed pairs
427 (final_needed, more_pretties) = go_rec needed' reduced_pairs
429 do_one needed (id,rhs) = case ifaceId get_idinfo needed True id rhs of
430 Nothing -> (needed, Nothing)
431 Just (pretty, needed') -> (needed', Just pretty)
435 %************************************************************************
437 \subsection{Random small things}
439 %************************************************************************
442 ifaceTyCons hdl tycons = hPutCol hdl upp_tycon (sortLt (<) (filter (for_iface_name . getName) tycons ))
443 ifaceClasses hdl classes = hPutCol hdl upp_class (sortLt (<) (filter (for_iface_name . getName) classes))
445 for_iface_name name = isLocallyDefined name &&
446 not (isWiredInName name)
448 upp_tycon tycon = ifaceTyCon tycon
449 upp_class clas = ifaceClass clas
454 ifaceTyCon :: TyCon -> SDoc
457 = hsep [ ptext SLIT("type"),
459 pprTyVarBndrs tyvars,
465 (tyvars, ty) = getSynTyConDefn tycon
469 = hsep [ ptext keyword,
470 ppr_decl_context (tyConTheta tycon),
472 pprTyVarBndrs (tyConTyVars tycon),
474 hsep (punctuate (ptext SLIT(" | ")) (map ppr_con (tyConDataCons tycon))),
478 keyword | isNewTyCon tycon = SLIT("newtype")
479 | otherwise = SLIT("data")
481 tyvars = tyConTyVars tycon
485 = ASSERT( tycon == tycon1 && tyvars == tyvars1 )
486 hsep [ ppr_ex ex_tyvars ex_theta,
488 hsep (map ppr_arg_ty (strict_marks `zip` arg_tys))
492 = hsep [ ppr_ex ex_tyvars ex_theta,
494 braces $ hsep $ punctuate comma (map ppr_field (strict_marks `zip` field_labels))
497 (tyvars1, theta1, ex_tyvars, ex_theta, arg_tys, tycon1) = dataConSig data_con
498 field_labels = dataConFieldLabels data_con
499 strict_marks = dataConStrictMarks data_con
500 name = getName data_con
502 ppr_ex [] ex_theta = ASSERT( null ex_theta ) empty
503 ppr_ex ex_tvs ex_theta = ptext SLIT("__forall") <+> brackets (pprTyVarBndrs ex_tvs)
504 <+> pprIfaceTheta ex_theta <+> ptext SLIT("=>")
506 ppr_arg_ty (strict_mark, ty) = ppr_strict_mark strict_mark <> pprParendType ty
508 ppr_strict_mark NotMarkedStrict = empty
509 ppr_strict_mark (MarkedUnboxed _ _) = ptext SLIT("! ! ")
510 ppr_strict_mark MarkedStrict = ptext SLIT("! ")
512 ppr_field (strict_mark, field_label)
513 = hsep [ ppr (fieldLabelName field_label),
515 ppr_strict_mark strict_mark <> pprParendType (fieldLabelType field_label)
519 = pprPanic "pprIfaceTyDecl" (ppr tycon)
522 = hsep [ptext SLIT("class"),
523 ppr_decl_context sc_theta,
524 ppr clas, -- Print the name
525 pprTyVarBndrs clas_tyvars,
530 (clas_tyvars, sc_theta, _, sel_ids, defms) = classBigSig clas
532 pp_ops | null sel_ids = empty
533 | otherwise = hsep [ptext SLIT("where"),
534 braces (hsep (punctuate semi (zipWith ppr_classop sel_ids defms)))
537 ppr_classop sel_id maybe_defm
538 = ASSERT( sel_tyvars == clas_tyvars)
539 hsep [ppr (getOccName sel_id),
540 if maybeToBool maybe_defm then equals else empty,
545 (sel_tyvars, _, op_ty) = splitSigmaTy (idType sel_id)
547 ppr_decl_context :: ThetaType -> SDoc
548 ppr_decl_context [] = empty
549 ppr_decl_context theta = pprIfaceTheta theta <+> ptext SLIT(" =>")
551 pprIfaceTheta :: ThetaType -> SDoc -- Use braces rather than parens in interface files
552 pprIfaceTheta [] = empty
553 pprIfaceTheta theta = braces (hsep (punctuate comma [pprConstraint c tys | (c,tys) <- theta]))
556 %************************************************************************
558 \subsection{Random small things}
560 %************************************************************************
562 When printing export lists, we print like this:
564 AvailTC C [C, x, y] C(x,y)
565 AvailTC C [x, y] C!(x,y) -- Exporting x, y but not C
568 upp_avail :: AvailInfo -> SDoc
569 upp_avail (Avail name) = pprOccName (getOccName name)
570 upp_avail (AvailTC name []) = empty
571 upp_avail (AvailTC name ns) = hcat [pprOccName (getOccName name), bang, upp_export ns']
573 bang | name `elem` ns = empty
574 | otherwise = char '|'
575 ns' = filter (/= name) ns
577 upp_export :: [Name] -> SDoc
578 upp_export [] = empty
579 upp_export names = braces (hsep (map (pprOccName . getOccName) names))
581 upp_fixity :: (Name, Fixity) -> SDoc
582 upp_fixity (name, fixity) = hsep [ptext SLIT("0"), ppr fixity, ppr name, semi]
583 -- Dummy version number!
585 ppr_unqual_name :: NamedThing a => a -> SDoc -- Just its occurrence name
586 ppr_unqual_name name = pprOccName (getOccName name)
590 %************************************************************************
592 \subsection{Comparisons
594 %************************************************************************
597 The various sorts above simply prevent unnecessary "wobbling" when
598 things change that don't have to. We therefore compare lexically, not
602 lt_avail :: AvailInfo -> AvailInfo -> Bool
604 a1 `lt_avail` a2 = availName a1 `lt_name` availName a2
606 lt_name :: Name -> Name -> Bool
607 n1 `lt_name` n2 = nameRdrName n1 < nameRdrName n2
609 lt_lexical :: NamedThing a => a -> a -> Bool
610 lt_lexical a1 a2 = getName a1 `lt_name` getName a2
612 lt_imp_vers :: ImportVersion a -> ImportVersion a -> Bool
613 lt_imp_vers (m1,_,_) (m2,_,_) = m1 < m2
615 sort_versions vs = sortLt lt_vers vs
617 lt_vers :: LocalVersion Name -> LocalVersion Name -> Bool
618 lt_vers (n1,v1) (n2,v2) = n1 `lt_name` n2
627 hPutCol hdl fmt xs = mapIO (printForIface hdl . fmt) xs
629 mapIO :: (a -> IO b) -> [a] -> IO ()
630 mapIO f [] = return ()
631 mapIO f (x:xs) = f x >> mapIO f xs