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 RdrHsSyn ( RdrName(..) )
20 import BasicTypes ( Fixity(..), FixityDirection(..), NewOrData(..), IfaceFlavour(..),
25 import RnEnv ( availName, ifaceFlavour )
27 import TcInstUtil ( InstInfo(..) )
28 import WorkWrap ( getWorkerIdAndCons )
31 import Id ( Id, idType, idInfo, omitIfaceSigForId,
36 import DataCon ( dataConSig, dataConFieldLabels, dataConStrictMarks )
37 import IdInfo ( IdInfo, StrictnessInfo, ArityInfo, InlinePragInfo(..), inlinePragInfo,
38 arityInfo, ppArityInfo,
39 strictnessInfo, ppStrictnessInfo,
41 bottomIsGuaranteed, workerExists,
43 import CoreSyn ( CoreExpr, CoreBind, Bind(..) )
44 import CoreUtils ( exprSomeFreeVars )
45 import CoreUnfold ( calcUnfoldingGuidance, UnfoldingGuidance(..),
46 Unfolding, okToUnfoldInHiFile )
47 import Name ( isLocallyDefined, isWiredInName, modAndOcc, nameModule,
48 OccName, occNameString, isExported,
51 import TyCon ( TyCon, getSynTyConDefn, isSynTyCon, isNewTyCon, isAlgTyCon,
52 tyConTheta, tyConTyVars, tyConDataCons
54 import Class ( Class, classBigSig )
55 import SpecEnv ( specEnvToList )
56 import FieldLabel ( fieldLabelName, fieldLabelType )
57 import Type ( mkSigmaTy, splitSigmaTy, mkDictTy,
62 import PprCore ( pprIfaceUnfolding )
64 import Bag ( bagToList, isEmptyBag )
65 import Maybes ( catMaybes, maybeToBool )
66 import FiniteMap ( emptyFM, addToFM, addToFM_C, fmToList, FiniteMap )
67 import UniqFM ( lookupUFM, listToUFM )
68 import UniqSet ( uniqSetToList )
69 import Util ( sortLt, mapAccumL )
73 We have a function @startIface@ to open the output file and put
74 (something like) ``interface Foo'' in it. It gives back a handle
75 for subsequent additions to the interface file.
77 We then have one-function-per-block-of-interface-stuff, e.g.,
78 @ifaceExportList@ produces the @__exports__@ section; it appends
79 to the handle provided by @startIface@.
83 -> IO (Maybe Handle) -- Nothing <=> don't do an interface
85 ifaceMain :: Maybe Handle
90 ifaceDecls :: Maybe Handle
93 -> [Id] -- Ids used at code-gen time; they have better pragma info!
94 -> [CoreBind] -- In dependency order, later depend on earlier
97 endIface :: Maybe Handle -> IO ()
102 = case opt_ProduceHi of
103 Nothing -> return Nothing -- not producing any .hi file
105 if_hdl <- openFile fn WriteMode
106 hPutStr if_hdl ("__interface "++ _UNPK_ mod ++ ' ':show (opt_HiVersion :: Int))
107 hPutStrLn if_hdl " where"
110 endIface Nothing = return ()
111 endIface (Just if_hdl) = hPutStr if_hdl "\n" >> hClose if_hdl
116 ifaceMain Nothing iface_stuff = return ()
117 ifaceMain (Just if_hdl)
118 (import_usages, ExportEnv avails fixities, instance_modules)
120 ifaceImports if_hdl import_usages
121 ifaceInstanceModules if_hdl instance_modules
122 ifaceExports if_hdl avails
123 ifaceFixities if_hdl fixities
126 ifaceDecls Nothing tycons classes inst_info final_ids simplified = return ()
127 ifaceDecls (Just hdl)
131 | null_decls = return ()
132 -- You could have a module with just (re-)exports/instances in it
134 = ifaceClasses hdl classes >>
135 ifaceInstances hdl inst_infos >>= \ needed_ids ->
136 ifaceTyCons hdl tycons >>
137 ifaceBinds hdl needed_ids final_ids binds >>
140 null_decls = null binds &&
143 isEmptyBag inst_infos
147 ifaceImports if_hdl import_usages
148 = hPutCol if_hdl upp_uses (sortLt lt_imp_vers import_usages)
150 upp_uses (m, hif, mv, whats_imported)
151 = ptext SLIT("import ") <>
152 hsep [pprModule m, pp_hif hif, int mv, ptext SLIT("::"),
153 upp_import_versions whats_imported
156 -- Importing the whole module is indicated by an empty list
157 upp_import_versions Everything = empty
159 -- For imported versions we do print the version number
160 upp_import_versions (Specifically nvs)
161 = hsep [ hsep [ppr_unqual_name n, int v] | (n,v) <- sort_versions nvs ]
163 ifaceInstanceModules if_hdl [] = return ()
164 ifaceInstanceModules if_hdl imods
165 = let sorted = sortLt (<) imods
166 lines = map (\m -> ptext SLIT("__instimport ") <> ptext m <>
167 ptext SLIT(" ;")) sorted
169 printForIface if_hdl (vcat lines) >>
172 ifaceExports if_hdl [] = return ()
173 ifaceExports if_hdl avails
174 = hPutCol if_hdl do_one_module (fmToList export_fm)
176 -- Sort them into groups by module
177 export_fm :: FiniteMap Module [AvailInfo]
178 export_fm = foldr insert emptyFM avails
180 insert NotAvailable efm = efm
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 [pp_hif (ifaceFlavour (availName avail1)),
191 hsep (map upp_avail (sortLt lt_avail avails))
194 -- The "!" indicates that the exported things came from a hi-boot interface
195 pp_hif HiFile = empty
196 pp_hif HiBootFile = char '!'
198 ifaceFixities if_hdl [] = return ()
199 ifaceFixities if_hdl fixities
200 = hPutCol if_hdl upp_fixity fixities
203 %************************************************************************
205 \subsection{Instance declarations}
207 %************************************************************************
211 ifaceInstances :: Handle -> Bag InstInfo -> IO IdSet -- The IdSet is the needed dfuns
212 ifaceInstances if_hdl inst_infos
213 | null togo_insts = return emptyVarSet
214 | otherwise = hPutCol if_hdl pp_inst (sortLt lt_inst togo_insts) >>
217 togo_insts = filter is_togo_inst (bagToList inst_infos)
218 needed_ids = mkVarSet [dfun_id | InstInfo _ _ _ _ dfun_id _ _ _ <- togo_insts]
219 is_togo_inst (InstInfo _ _ _ _ dfun_id _ _ _) = isLocallyDefined dfun_id
222 lt_inst (InstInfo _ _ _ _ dfun_id1 _ _ _)
223 (InstInfo _ _ _ _ dfun_id2 _ _ _)
224 = getOccName dfun_id1 < getOccName dfun_id2
225 -- The dfuns are assigned names df1, df2, etc, in order of original textual
226 -- occurrence, and this makes as good a sort order as any
229 pp_inst (InstInfo clas tvs tys theta dfun_id _ _ _)
231 forall_ty = mkSigmaTy tvs theta (mkDictTy clas tys)
232 renumbered_ty = nmbrGlobalType forall_ty
234 hcat [ptext SLIT("instance "), pprType renumbered_ty,
235 ptext SLIT(" = "), ppr_unqual_name dfun_id, semi]
239 %************************************************************************
241 \subsection{Printing values}
243 %************************************************************************
246 ifaceId :: (Id -> IdInfo) -- This function "knows" the extra info added
247 -- by the STG passes. Sigh
249 -> IdSet -- Set of Ids that are needed by earlier interface
250 -- file emissions. If the Id isn't in this set, and isn't
251 -- exported, there's no need to emit anything
252 -> Bool -- True <=> recursive, so don't print unfolding
254 -> CoreExpr -- The Id's right hand side
255 -> Maybe (SDoc, IdSet) -- The emitted stuff, plus a possibly-augmented set of needed Ids
257 ifaceId get_idinfo needed_ids is_rec id rhs
258 | not (id `elemVarSet` needed_ids || -- Needed [no id in needed_ids has omitIfaceSigForId]
259 (isExported id && not (omitIfaceSigForId id))) -- or exported and not to be omitted
260 = Nothing -- Well, that was easy!
262 ifaceId get_idinfo needed_ids is_rec id rhs
263 = Just (hsep [sig_pretty, prag_pretty, char ';'], new_needed_ids)
265 idinfo = get_idinfo id
266 inline_pragma = inlinePragInfo idinfo
268 ty_pretty = pprType (nmbrGlobalType (idType id))
269 sig_pretty = hcat [ppr (getOccName id), ptext SLIT(" :: "), ty_pretty]
272 | opt_OmitInterfacePragmas = empty
273 | otherwise = hsep [ptext SLIT("{-##"),
281 ------------ Arity --------------
282 arity_pretty = ppArityInfo (arityInfo idinfo)
284 ------------ Caf Info --------------
285 caf_pretty = ppCafInfo (cafInfo idinfo)
287 ------------ Strictness --------------
288 strict_info = strictnessInfo idinfo
289 has_worker = workerExists strict_info
290 strict_pretty = ppStrictnessInfo strict_info <+> wrkr_pretty
292 wrkr_pretty | not has_worker = empty
293 | null con_list = ppr work_id
294 | otherwise = ppr work_id <+>
295 braces (hsep (map ppr con_list))
297 (work_id, wrapper_cons) = getWorkerIdAndCons id rhs
298 con_list = uniqSetToList wrapper_cons
300 ------------ Unfolding --------------
301 unfold_pretty | show_unfold = unfold_herald <+> pprIfaceUnfolding rhs
304 show_unfold = not implicit_unfolding && -- Not unnecessary
305 unfolding_needed -- Not dangerous
307 unfolding_needed = case inline_pragma of
308 IMustBeINLINEd -> definitely_ok_to_unfold
309 IWantToBeINLINEd -> definitely_ok_to_unfold
310 NoInlinePragInfo -> rhs_is_small
313 implicit_unfolding = has_worker ||
314 bottomIsGuaranteed strict_info
316 unfold_herald = case inline_pragma of
317 NoInlinePragInfo -> ptext SLIT("__u")
318 other -> ppr inline_pragma
320 rhs_is_small = case calcUnfoldingGuidance opt_InterfaceUnfoldThreshold rhs of
321 UnfoldNever -> False -- Too big
322 other -> definitely_ok_to_unfold -- Small enough
324 definitely_ok_to_unfold = okToUnfoldInHiFile rhs
326 ------------ Specialisations --------------
327 spec_list = specEnvToList (getIdSpecialisation id)
328 spec_pretty = hsep (map pp_spec spec_list)
329 pp_spec (tyvars, tys, rhs) = hsep [ptext SLIT("__P"),
330 if null tyvars then ptext SLIT("[ ]")
331 else brackets (interppSP tyvars),
332 -- The lexer interprets "[]" as a CONID. Sigh.
333 hsep (map pprParendType tys),
335 pprIfaceUnfolding rhs
338 ------------ Extra free Ids --------------
339 new_needed_ids = (needed_ids `minusVarSet` unitVarSet id) `unionVarSet`
342 extra_ids | opt_OmitInterfacePragmas = emptyVarSet
343 | otherwise = worker_ids `unionVarSet`
344 unfold_ids `unionVarSet`
347 worker_ids | has_worker = unitVarSet work_id
348 | otherwise = emptyVarSet
350 spec_ids = foldr add emptyVarSet spec_list
352 add (_, _, rhs) = unionVarSet (find_fvs rhs)
354 unfold_ids | show_unfold = find_fvs rhs
355 | otherwise = emptyVarSet
357 find_fvs expr = free_vars
359 free_vars = exprSomeFreeVars interesting expr
360 interesting id = isId id && isLocallyDefined id &&
361 not (omitIfaceSigForId id)
366 -> IdSet -- These Ids are needed already
367 -> [Id] -- Ids used at code-gen time; they have better pragma info!
368 -> [CoreBind] -- In dependency order, later depend on earlier
371 ifaceBinds hdl needed_ids final_ids binds
372 = mapIO (printForIface hdl) pretties >>
375 final_id_map = listToUFM [(id,id) | id <- final_ids]
376 get_idinfo id = case lookupUFM final_id_map id of
377 Just id' -> idInfo id'
378 Nothing -> pprTrace "ifaceBinds not found:" (ppr id) $
381 pretties = go needed_ids (reverse binds) -- Reverse so that later things will
382 -- provoke earlier ones to be emitted
383 go needed [] = if not (isEmptyVarSet needed) then
384 pprTrace "ifaceBinds: free vars:"
385 (sep (map ppr (varSetElems needed))) $
390 go needed (NonRec id rhs : binds)
391 = case ifaceId get_idinfo needed False id rhs of
392 Nothing -> go needed binds
393 Just (pretty, needed') -> pretty : go needed' binds
395 -- Recursive groups are a bit more of a pain. We may only need one to
396 -- start with, but it may call out the next one, and so on. So we
397 -- have to look for a fixed point.
398 go needed (Rec pairs : binds)
399 = pretties ++ go needed'' binds
401 (needed', pretties) = go_rec needed pairs
402 needed'' = needed' `minusVarSet` mkVarSet (map fst pairs)
403 -- Later ones may spuriously cause earlier ones to be "needed" again
405 go_rec :: IdSet -> [(Id,CoreExpr)] -> (IdSet, [SDoc])
407 | null pretties = (needed, [])
408 | otherwise = (final_needed, more_pretties ++ pretties)
410 reduced_pairs = [pair | (pair,Nothing) <- pairs `zip` maybes]
411 pretties = catMaybes maybes
412 (needed', maybes) = mapAccumL do_one needed pairs
413 (final_needed, more_pretties) = go_rec needed' reduced_pairs
415 do_one needed (id,rhs) = case ifaceId get_idinfo needed True id rhs of
416 Nothing -> (needed, Nothing)
417 Just (pretty, needed') -> (needed', Just pretty)
421 %************************************************************************
423 \subsection{Random small things}
425 %************************************************************************
428 ifaceTyCons hdl tycons = hPutCol hdl upp_tycon (sortLt (<) (filter (for_iface_name . getName) tycons ))
429 ifaceClasses hdl classes = hPutCol hdl upp_class (sortLt (<) (filter (for_iface_name . getName) classes))
431 for_iface_name name = isLocallyDefined name &&
432 not (isWiredInName name)
434 upp_tycon tycon = ifaceTyCon tycon
435 upp_class clas = ifaceClass clas
440 ifaceTyCon :: TyCon -> SDoc
443 = hsep [ ptext SLIT("type"),
445 pprTyVarBndrs tyvars,
451 (tyvars, ty) = getSynTyConDefn tycon
455 = hsep [ ptext keyword,
456 ppr_decl_context (tyConTheta tycon),
458 pprTyVarBndrs (tyConTyVars tycon),
460 hsep (punctuate (ptext SLIT(" | ")) (map ppr_con (tyConDataCons tycon))),
464 keyword | isNewTyCon tycon = SLIT("newtype")
465 | otherwise = SLIT("data")
467 tyvars = tyConTyVars tycon
471 = ASSERT( tycon == tycon1 && tyvars == tyvars1 )
472 hsep [ ppr_ex ex_tyvars ex_theta,
474 hsep (map ppr_arg_ty (strict_marks `zip` arg_tys))
478 = hsep [ ppr_ex ex_tyvars ex_theta,
480 braces $ hsep $ punctuate comma (map ppr_field (strict_marks `zip` field_labels))
483 (tyvars1, theta1, ex_tyvars, ex_theta, arg_tys, tycon1) = dataConSig data_con
484 field_labels = dataConFieldLabels data_con
485 strict_marks = dataConStrictMarks data_con
486 name = getName data_con
488 ppr_ex [] ex_theta = ASSERT( null ex_theta ) empty
489 ppr_ex ex_tvs ex_theta = ptext SLIT("__forall") <+> brackets (pprTyVarBndrs ex_tvs)
490 <+> pprIfaceTheta ex_theta <+> ptext SLIT("=>")
492 ppr_arg_ty (strict_mark, ty) = ppr_strict_mark strict_mark <> pprParendType ty
494 ppr_strict_mark NotMarkedStrict = empty
495 ppr_strict_mark MarkedStrict = ptext SLIT("! ")
496 -- The extra space helps the lexical analyser that lexes
497 -- interface files; it doesn't make the rigid operator/identifier
498 -- distinction, so "!a" is a valid identifier so far as it is concerned
500 ppr_field (strict_mark, field_label)
501 = hsep [ ppr (fieldLabelName field_label),
503 ppr_strict_mark strict_mark <> pprParendType (fieldLabelType field_label)
507 = pprPanic "pprIfaceTyDecl" (ppr tycon)
510 = hsep [ptext SLIT("class"),
511 ppr_decl_context sc_theta,
512 ppr clas, -- Print the name
513 pprTyVarBndrs clas_tyvars,
518 (clas_tyvars, sc_theta, _, sel_ids, defms) = classBigSig clas
520 pp_ops | null sel_ids = empty
521 | otherwise = hsep [ptext SLIT("where"),
522 braces (hsep (punctuate semi (zipWith ppr_classop sel_ids defms)))
525 ppr_classop sel_id maybe_defm
526 = ASSERT( sel_tyvars == clas_tyvars)
527 hsep [ppr (getOccName sel_id),
528 if maybeToBool maybe_defm then equals else empty,
533 (sel_tyvars, _, op_ty) = splitSigmaTy (idType sel_id)
535 ppr_decl_context :: ThetaType -> SDoc
536 ppr_decl_context [] = empty
537 ppr_decl_context theta = pprIfaceTheta theta <+> ptext SLIT(" =>")
539 pprIfaceTheta :: ThetaType -> SDoc -- Use braces rather than parens in interface files
540 pprIfaceTheta theta = braces (hsep (punctuate comma [pprConstraint c tys | (c,tys) <- theta]))
543 %************************************************************************
545 \subsection{Random small things}
547 %************************************************************************
549 When printing export lists, we print like this:
551 AvailTC C [C, x, y] C(x,y)
552 AvailTC C [x, y] C!(x,y) -- Exporting x, y but not C
555 upp_avail NotAvailable = empty
556 upp_avail (Avail name) = upp_occname (getOccName name)
557 upp_avail (AvailTC name []) = empty
558 upp_avail (AvailTC name ns) = hcat [upp_occname (getOccName name), bang, upp_export ns']
560 bang | name `elem` ns = empty
561 | otherwise = char '|'
562 ns' = filter (/= name) ns
564 upp_export [] = empty
565 upp_export names = braces (hsep (map (upp_occname . getOccName) names))
567 upp_fixity (occ, fixity) = hcat [ppr fixity, space, upp_occname occ, semi]
569 ppr_unqual_name :: NamedThing a => a -> SDoc -- Just its occurrence name
570 ppr_unqual_name name = upp_occname (getOccName name)
572 upp_occname :: OccName -> SDoc
573 upp_occname occ = ptext (occNameString occ)
577 %************************************************************************
579 \subsection{Comparisons
581 %************************************************************************
584 The various sorts above simply prevent unnecessary "wobbling" when
585 things change that don't have to. We therefore compare lexically, not
589 lt_avail :: AvailInfo -> AvailInfo -> Bool
591 a1 `lt_avail` a2 = availName a1 `lt_name` availName a2
593 lt_name :: Name -> Name -> Bool
594 n1 `lt_name` n2 = modAndOcc n1 < modAndOcc n2
596 lt_lexical :: NamedThing a => a -> a -> Bool
597 lt_lexical a1 a2 = getName a1 `lt_name` getName a2
599 lt_imp_vers :: ImportVersion a -> ImportVersion a -> Bool
600 lt_imp_vers (m1,_,_,_) (m2,_,_,_) = m1 < m2
602 sort_versions vs = sortLt lt_vers vs
604 lt_vers :: LocalVersion Name -> LocalVersion Name -> Bool
605 lt_vers (n1,v1) (n2,v2) = n1 `lt_name` n2
614 hPutCol hdl fmt xs = mapIO (printForIface hdl . fmt) xs
616 mapIO :: (a -> IO b) -> [a] -> IO ()
617 mapIO f [] = return ()
618 mapIO f (x:xs) = f x >> mapIO f xs