2 % (c) The GRASP/AQUA Project, Glasgow University, 1993-1998
4 \section[MkIface]{Print an interface for a module}
8 startIface, endIface, ifaceDecls
11 #include "HsVersions.h"
13 import IO ( Handle, hPutStr, openFile,
14 hClose, hPutStrLn, IOMode(..) )
17 import BasicTypes ( Fixity(..), FixityDirection(..), NewOrData(..) )
19 import RnEnv ( availName )
21 import TcInstUtil ( InstInfo(..) )
24 import Id ( Id, idType, idInfo, omitIfaceSigForId, isUserExportedId,
29 import DataCon ( StrictnessMark(..), dataConSig, dataConFieldLabels, dataConStrictMarks )
30 import IdInfo ( IdInfo, StrictnessInfo(..), ArityInfo, InlinePragInfo(..), inlinePragInfo,
31 arityInfo, ppArityInfo, arityLowerBound,
32 strictnessInfo, ppStrictnessInfo, isBottomingStrictness,
33 cafInfo, ppCafInfo, specInfo,
34 cprInfo, ppCprInfo, pprInlinePragInfo,
36 workerExists, workerInfo, ppWorkerInfo
38 import CoreSyn ( CoreExpr, CoreBind, Bind(..), rulesRules, rulesRhsFreeVars )
39 import CoreFVs ( exprSomeFreeVars, ruleSomeLhsFreeVars, ruleSomeFreeVars )
40 import CoreUnfold ( calcUnfoldingGuidance, okToUnfoldInHiFile, couldBeSmallEnoughToInline )
41 import Module ( moduleString, pprModule, pprModuleName )
42 import Name ( isLocallyDefined, isWiredInName, nameRdrName, nameModule,
45 import OccName ( OccName, pprOccName )
46 import TyCon ( TyCon, getSynTyConDefn, isSynTyCon, isNewTyCon, isAlgTyCon,
47 tyConTheta, tyConTyVars, tyConDataCons
49 import Class ( Class, classBigSig )
50 import FieldLabel ( fieldLabelName, fieldLabelType )
51 import Type ( mkSigmaTy, splitSigmaTy, mkDictTy, tidyTopType, deNoteType,
56 import PprCore ( pprIfaceUnfolding, pprCoreRule )
57 import Rules ( pprProtoCoreRule, ProtoCoreRule(..) )
59 import Bag ( bagToList, isEmptyBag )
60 import Maybes ( catMaybes, maybeToBool )
61 import FiniteMap ( emptyFM, addToFM, addToFM_C, fmToList, FiniteMap )
62 import UniqFM ( lookupUFM, listToUFM )
63 import UniqSet ( uniqSetToList )
64 import Util ( sortLt, mapAccumL )
69 We have a function @startIface@ to open the output file and put
70 (something like) ``interface Foo'' in it. It gives back a handle
71 for subsequent additions to the interface file.
73 We then have one-function-per-block-of-interface-stuff, e.g.,
74 @ifaceExportList@ produces the @__exports__@ section; it appends
75 to the handle provided by @startIface@.
78 startIface :: Module -> InterfaceDetails
79 -> IO (Maybe Handle) -- Nothing <=> don't do an interface
81 ifaceDecls :: Maybe Handle
84 -> [Id] -- Ids used at code-gen time; they have better pragma info!
85 -> [CoreBind] -- In dependency order, later depend on earlier
86 -> [ProtoCoreRule] -- Rules
89 endIface :: Maybe Handle -> IO ()
93 startIface mod (has_orphans, import_usages, ExportEnv avails fixities)
94 = case opt_ProduceHi of
95 Nothing -> return Nothing ; -- not producing any .hi file
98 if_hdl <- openFile fn WriteMode
99 hPutStr if_hdl ("__interface " ++ moduleString mod)
100 hPutStr if_hdl (' ' : show (opt_HiVersion :: Int) ++ orphan_indicator)
101 hPutStrLn if_hdl " where"
102 ifaceExports if_hdl avails
103 ifaceImports if_hdl import_usages
104 ifaceFixities if_hdl fixities
107 orphan_indicator | has_orphans = " !"
110 endIface Nothing = return ()
111 endIface (Just if_hdl) = hPutStr if_hdl "\n" >> hClose if_hdl
116 ifaceDecls Nothing tycons classes inst_info final_ids simplified rules = return ()
117 ifaceDecls (Just hdl)
121 orphan_rules -- Rules defined locally for an Id that is *not* defined locally
122 | null_decls = return ()
123 -- You could have a module with just (re-)exports/instances in it
125 = ifaceClasses hdl classes >>
126 ifaceInstances hdl inst_infos >>= \ inst_ids ->
127 ifaceTyCons hdl tycons >>
128 ifaceBinds hdl (inst_ids `unionVarSet` orphan_rule_ids)
129 final_ids binds >>= \ emitted_ids ->
130 ifaceRules hdl orphan_rules emitted_ids >>
133 orphan_rule_ids = unionVarSets [ ruleSomeFreeVars interestingId rule
134 | ProtoCoreRule _ _ rule <- orphan_rules]
136 null_decls = null binds &&
139 isEmptyBag inst_infos &&
144 ifaceImports if_hdl import_usages
145 = hPutCol if_hdl upp_uses (sortLt lt_imp_vers import_usages)
147 upp_uses (m, mv, has_orphans, whats_imported)
148 = hsep [ptext SLIT("import"), pprModuleName m,
150 upp_import_versions whats_imported
153 pp_orphan | has_orphans = ptext SLIT("!")
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 = dcolon <+> hsep [ hsep [ppr_unqual_name n, int v] | (n,v) <- sort_versions nvs ]
163 ifaceModuleDeps if_hdl [] = return ()
164 ifaceModuleDeps if_hdl mod_deps
166 lines = map ppr_mod_dep mod_deps
167 ppr_mod_dep (mod, contains_orphans)
168 | contains_orphans = pprModuleName mod <+> ptext SLIT("!")
169 | otherwise = pprModuleName mod
171 printForIface if_hdl (ptext SLIT("__depends") <+> vcat lines <> ptext SLIT(" ;")) >>
174 ifaceExports if_hdl [] = return ()
175 ifaceExports if_hdl avails
176 = hPutCol if_hdl do_one_module (fmToList export_fm)
178 -- Sort them into groups by module
179 export_fm :: FiniteMap Module [AvailInfo]
180 export_fm = foldr insert emptyFM avails
182 insert avail efm = addToFM_C (++) efm mod [avail]
184 mod = nameModule (availName avail)
186 -- Print one module's worth of stuff
187 do_one_module :: (Module, [AvailInfo]) -> SDoc
188 do_one_module (mod_name, avails@(avail1:_))
189 = ptext SLIT("__export ") <>
190 hsep [pprModule mod_name,
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
198 ifaceRules if_hdl rules emitted
199 | null orphan_rule_pretties && null local_id_pretties
202 = do printForIface if_hdl (vcat [
203 ptext SLIT("{-## __R"),
205 vcat orphan_rule_pretties,
207 vcat local_id_pretties,
214 orphan_rule_pretties = [ pprCoreRule (Just fn) rule <+> semi
215 | ProtoCoreRule _ fn rule <- rules
217 local_id_pretties = [ pprCoreRule (Just fn) rule <+> semi
218 | fn <- varSetElems emitted,
219 rule <- rulesRules (getIdSpecialisation fn),
220 all (`elemVarSet` emitted) (varSetElems (ruleSomeLhsFreeVars interestingId rule))
221 -- Spit out a rule only if all its lhs free vars are eemitted
225 %************************************************************************
227 \subsection{Instance declarations}
229 %************************************************************************
233 ifaceInstances :: Handle -> Bag InstInfo -> IO IdSet -- The IdSet is the needed dfuns
234 ifaceInstances if_hdl inst_infos
235 | null togo_insts = return emptyVarSet
236 | otherwise = hPutCol if_hdl pp_inst (sortLt lt_inst togo_insts) >>
239 togo_insts = filter is_togo_inst (bagToList inst_infos)
240 needed_ids = mkVarSet [dfun_id | InstInfo _ _ _ _ dfun_id _ _ _ <- togo_insts]
241 is_togo_inst (InstInfo _ _ _ _ dfun_id _ _ _) = isLocallyDefined dfun_id
244 lt_inst (InstInfo _ _ _ _ dfun_id1 _ _ _)
245 (InstInfo _ _ _ _ dfun_id2 _ _ _)
246 = getOccName dfun_id1 < getOccName dfun_id2
247 -- The dfuns are assigned names df1, df2, etc, in order of original textual
248 -- occurrence, and this makes as good a sort order as any
251 pp_inst (InstInfo clas tvs tys theta dfun_id _ _ _)
253 -- The deNoteType is very important. It removes all type
254 -- synonyms from the instance type in interface files.
255 -- That in turn makes sure that when reading in instance decls
256 -- from interface files that the 'gating' mechanism works properly.
257 -- Otherwise you could have
258 -- type Tibble = T Int
259 -- instance Foo Tibble where ...
260 -- and this instance decl wouldn't get imported into a module
261 -- that mentioned T but not Tibble.
262 forall_ty = mkSigmaTy tvs theta (deNoteType (mkDictTy clas tys))
263 renumbered_ty = tidyTopType forall_ty
265 hcat [ptext SLIT("instance "), pprType renumbered_ty,
266 ptext SLIT(" = "), ppr_unqual_name dfun_id, semi]
270 %************************************************************************
272 \subsection{Printing values}
274 %************************************************************************
277 ifaceId :: (Id -> IdInfo) -- This function "knows" the extra info added
278 -- by the STG passes. Sigh
280 -> IdSet -- Set of Ids that are needed by earlier interface
281 -- file emissions. If the Id isn't in this set, and isn't
282 -- exported, there's no need to emit anything
283 -> Bool -- True <=> recursive, so don't print unfolding
285 -> CoreExpr -- The Id's right hand side
286 -> Maybe (SDoc, IdSet) -- The emitted stuff, plus any *extra* needed Ids
288 ifaceId get_idinfo needed_ids is_rec id rhs
289 | not (id `elemVarSet` needed_ids || -- Needed [no id in needed_ids has omitIfaceSigForId]
290 (isUserExportedId id && not (omitIfaceSigForId id))) -- or exported and not to be omitted
291 = Nothing -- Well, that was easy!
293 ifaceId get_idinfo needed_ids is_rec id rhs
294 = ASSERT2( arity_matches_strictness, ppr id )
295 Just (hsep [sig_pretty, prag_pretty, char ';'], new_needed_ids)
297 core_idinfo = idInfo id
298 stg_idinfo = get_idinfo id
300 ty_pretty = pprType (idType id)
301 sig_pretty = hsep [ppr (getOccName id), dcolon, ty_pretty]
304 | opt_OmitInterfacePragmas = empty
305 | otherwise = hsep [ptext SLIT("{-##"),
314 ------------ Arity --------------
315 arity_info = arityInfo stg_idinfo
316 arity_pretty = ppArityInfo arity_info
318 ------------ Caf Info --------------
319 caf_pretty = ppCafInfo (cafInfo stg_idinfo)
321 ------------ CPR Info --------------
322 cpr_pretty = ppCprInfo (cprInfo core_idinfo)
324 ------------ Strictness --------------
325 strict_info = strictnessInfo core_idinfo
326 bottoming_fn = isBottomingStrictness strict_info
327 strict_pretty = ppStrictnessInfo strict_info
329 ------------ Worker --------------
330 work_info = workerInfo core_idinfo
331 has_worker = workerExists work_info
332 wrkr_pretty = ppWorkerInfo work_info
333 Just work_id = work_info
336 ------------ Occ info --------------
337 loop_breaker = case occInfo core_idinfo of
338 IAmALoopBreaker -> True
341 ------------ Unfolding --------------
342 inline_pragma = inlinePragInfo core_idinfo
343 dont_inline = case inline_pragma of
344 IMustNotBeINLINEd False Nothing -> True -- Unconditional NOINLINE
348 unfold_pretty | show_unfold = ptext SLIT("__U") <> pprInlinePragInfo inline_pragma <+> pprIfaceUnfolding rhs
351 show_unfold = not has_worker && -- Not unnecessary
352 not bottoming_fn && -- Not necessary
355 rhs_is_small && -- Small enough
356 okToUnfoldInHiFile rhs -- No casms etc
358 rhs_is_small = couldBeSmallEnoughToInline (calcUnfoldingGuidance opt_UF_HiFileThreshold rhs)
360 ------------ Specialisations --------------
361 spec_info = specInfo core_idinfo
363 ------------ Extra free Ids --------------
364 new_needed_ids | opt_OmitInterfacePragmas = emptyVarSet
365 | otherwise = worker_ids `unionVarSet`
366 unfold_ids `unionVarSet`
369 worker_ids | has_worker && interestingId work_id = unitVarSet work_id
370 -- Conceivably, the worker might come from
372 | otherwise = emptyVarSet
374 spec_ids = filterVarSet interestingId (rulesRhsFreeVars spec_info)
376 unfold_ids | show_unfold = find_fvs rhs
377 | otherwise = emptyVarSet
379 find_fvs expr = exprSomeFreeVars interestingId expr
381 ------------ Sanity checking --------------
382 -- The arity of a wrapper function should match its strictness,
383 -- or else an importing module will get very confused indeed.
384 -- [later: actually all that is necessary is for strictness to exceed arity]
385 arity_matches_strictness
388 StrictnessInfo ds _ -> length ds >= arityLowerBound arity_info
391 interestingId id = isId id && isLocallyDefined id &&
392 not (omitIfaceSigForId id)
397 -> IdSet -- These Ids are needed already
398 -> [Id] -- Ids used at code-gen time; they have better pragma info!
399 -> [CoreBind] -- In dependency order, later depend on earlier
400 -> IO IdSet -- Set of Ids actually spat out
402 ifaceBinds hdl needed_ids final_ids binds
403 = mapIO (printForIface hdl) (bagToList pretties) >>
407 final_id_map = listToUFM [(id,id) | id <- final_ids]
408 get_idinfo id = case lookupUFM final_id_map id of
409 Just id' -> idInfo id'
410 Nothing -> pprTrace "ifaceBinds not found:" (ppr id) $
413 (pretties, emitted) = go needed_ids (reverse binds) emptyBag emptyVarSet
414 -- Reverse so that later things will
415 -- provoke earlier ones to be emitted
416 go needed [] pretties emitted
417 | not (isEmptyVarSet needed) = pprTrace "ifaceBinds: free vars:"
418 (sep (map ppr (varSetElems needed)))
420 | otherwise = (pretties, emitted)
422 go needed (NonRec id rhs : binds) pretties emitted
423 = case ifaceId get_idinfo needed False id rhs of
424 Nothing -> go needed binds pretties emitted
425 Just (pretty, extras) -> let
426 needed' = (needed `unionVarSet` extras) `delVarSet` id
427 -- 'extras' can include the Id itself via a rule
428 emitted' = emitted `extendVarSet` id
430 go needed' binds (pretty `consBag` pretties) emitted'
432 -- Recursive groups are a bit more of a pain. We may only need one to
433 -- start with, but it may call out the next one, and so on. So we
434 -- have to look for a fixed point.
435 go needed (Rec pairs : binds) pretties emitted
436 = go needed' binds pretties' emitted'
438 (new_pretties, new_emitted, extras) = go_rec needed pairs
439 pretties' = new_pretties `unionBags` pretties
440 needed' = (needed `unionVarSet` extras) `minusVarSet` mkVarSet (map fst pairs)
441 emitted' = emitted `unionVarSet` new_emitted
443 go_rec :: IdSet -> [(Id,CoreExpr)] -> (Bag SDoc, IdSet, IdSet)
445 | null pretties = (emptyBag, emptyVarSet, emptyVarSet)
446 | otherwise = (more_pretties `unionBags` listToBag pretties,
447 more_emitted `unionVarSet` mkVarSet emitted,
448 more_extras `unionVarSet` extras)
450 maybes = map do_one pairs
451 emitted = [id | ((id,_), Just _) <- pairs `zip` maybes]
452 reduced_pairs = [pair | (pair, Nothing) <- pairs `zip` maybes]
453 (pretties, extras_s) = unzip (catMaybes maybes)
454 extras = unionVarSets extras_s
455 (more_pretties, more_emitted, more_extras) = go_rec extras reduced_pairs
457 do_one (id,rhs) = ifaceId get_idinfo needed True id rhs
461 %************************************************************************
463 \subsection{Random small things}
465 %************************************************************************
468 ifaceTyCons hdl tycons = hPutCol hdl upp_tycon (sortLt (<) (filter (for_iface_name . getName) tycons ))
469 ifaceClasses hdl classes = hPutCol hdl upp_class (sortLt (<) (filter (for_iface_name . getName) classes))
471 for_iface_name name = isLocallyDefined name &&
472 not (isWiredInName name)
474 upp_tycon tycon = ifaceTyCon tycon
475 upp_class clas = ifaceClass clas
480 ifaceTyCon :: TyCon -> SDoc
483 = hsep [ ptext SLIT("type"),
485 pprTyVarBndrs tyvars,
491 (tyvars, ty) = getSynTyConDefn tycon
495 = hsep [ ptext keyword,
496 ppr_decl_context (tyConTheta tycon),
498 pprTyVarBndrs (tyConTyVars tycon),
500 hsep (punctuate (ptext SLIT(" | ")) (map ppr_con (tyConDataCons tycon))),
504 keyword | isNewTyCon tycon = SLIT("newtype")
505 | otherwise = SLIT("data")
507 tyvars = tyConTyVars tycon
511 = ASSERT( tycon == tycon1 && tyvars == tyvars1 )
512 hsep [ ppr_ex ex_tyvars ex_theta,
514 hsep (map ppr_arg_ty (strict_marks `zip` arg_tys))
518 = hsep [ ppr_ex ex_tyvars ex_theta,
520 braces $ hsep $ punctuate comma (map ppr_field (strict_marks `zip` field_labels))
523 (tyvars1, theta1, ex_tyvars, ex_theta, arg_tys, tycon1) = dataConSig data_con
524 field_labels = dataConFieldLabels data_con
525 strict_marks = dataConStrictMarks data_con
526 name = getName data_con
528 ppr_ex [] ex_theta = ASSERT( null ex_theta ) empty
529 ppr_ex ex_tvs ex_theta = ptext SLIT("__forall") <+> brackets (pprTyVarBndrs ex_tvs)
530 <+> pprIfaceTheta ex_theta <+> ptext SLIT("=>")
532 ppr_arg_ty (strict_mark, ty) = ppr_strict_mark strict_mark <> pprParendType ty
534 ppr_strict_mark NotMarkedStrict = empty
535 ppr_strict_mark (MarkedUnboxed _ _) = ptext SLIT("! ! ")
536 ppr_strict_mark MarkedStrict = ptext SLIT("! ")
538 ppr_field (strict_mark, field_label)
539 = hsep [ ppr (fieldLabelName field_label),
541 ppr_strict_mark strict_mark <> pprParendType (fieldLabelType field_label)
545 = pprPanic "pprIfaceTyDecl" (ppr tycon)
548 = hsep [ptext SLIT("class"),
549 ppr_decl_context sc_theta,
550 ppr clas, -- Print the name
551 pprTyVarBndrs clas_tyvars,
556 (clas_tyvars, sc_theta, _, sel_ids, defms) = classBigSig clas
558 pp_ops | null sel_ids = empty
559 | otherwise = hsep [ptext SLIT("where"),
560 braces (hsep (punctuate semi (zipWith ppr_classop sel_ids defms)))
563 ppr_classop sel_id maybe_defm
564 = ASSERT( sel_tyvars == clas_tyvars)
565 hsep [ppr (getOccName sel_id),
566 if maybeToBool maybe_defm then equals else empty,
571 (sel_tyvars, _, op_ty) = splitSigmaTy (idType sel_id)
573 ppr_decl_context :: ThetaType -> SDoc
574 ppr_decl_context [] = empty
575 ppr_decl_context theta = pprIfaceTheta theta <+> ptext SLIT(" =>")
577 pprIfaceTheta :: ThetaType -> SDoc -- Use braces rather than parens in interface files
578 pprIfaceTheta [] = empty
579 pprIfaceTheta theta = braces (hsep (punctuate comma [pprConstraint c tys | (c,tys) <- theta]))
582 %************************************************************************
584 \subsection{Random small things}
586 %************************************************************************
588 When printing export lists, we print like this:
590 AvailTC C [C, x, y] C(x,y)
591 AvailTC C [x, y] C!(x,y) -- Exporting x, y but not C
594 upp_avail :: AvailInfo -> SDoc
595 upp_avail (Avail name) = pprOccName (getOccName name)
596 upp_avail (AvailTC name []) = empty
597 upp_avail (AvailTC name ns) = hcat [pprOccName (getOccName name), bang, upp_export ns']
599 bang | name `elem` ns = empty
600 | otherwise = char '|'
601 ns' = filter (/= name) ns
603 upp_export :: [Name] -> SDoc
604 upp_export [] = empty
605 upp_export names = braces (hsep (map (pprOccName . getOccName) names))
607 upp_fixity :: (Name, Fixity) -> SDoc
608 upp_fixity (name, fixity) = hsep [ptext SLIT("0"), ppr fixity, ppr name, semi]
609 -- Dummy version number!
611 ppr_unqual_name :: NamedThing a => a -> SDoc -- Just its occurrence name
612 ppr_unqual_name name = pprOccName (getOccName name)
616 %************************************************************************
618 \subsection{Comparisons}
620 %************************************************************************
623 The various sorts above simply prevent unnecessary "wobbling" when
624 things change that don't have to. We therefore compare lexically, not
628 lt_avail :: AvailInfo -> AvailInfo -> Bool
630 a1 `lt_avail` a2 = availName a1 `lt_name` availName a2
632 lt_name :: Name -> Name -> Bool
633 n1 `lt_name` n2 = nameRdrName n1 < nameRdrName n2
635 lt_lexical :: NamedThing a => a -> a -> Bool
636 lt_lexical a1 a2 = getName a1 `lt_name` getName a2
638 lt_imp_vers :: ImportVersion a -> ImportVersion a -> Bool
639 lt_imp_vers (m1,_,_,_) (m2,_,_,_) = m1 < m2
641 sort_versions vs = sortLt lt_vers vs
643 lt_vers :: LocalVersion Name -> LocalVersion Name -> Bool
644 lt_vers (n1,v1) (n2,v2) = n1 `lt_name` n2
653 hPutCol hdl fmt xs = mapIO (printForIface hdl . fmt) xs
655 mapIO :: (a -> IO b) -> [a] -> IO ()
656 mapIO f [] = return ()
657 mapIO f (x:xs) = f x >> mapIO f xs