2 % (c) The University of Glasgow 2006
3 % (c) The GRASP/AQUA Project, Glasgow University, 1993-1998
8 -- The above warning supression flag is a temporary kludge.
9 -- While working on this module you are encouraged to remove it and fix
10 -- any warnings in the module. See
11 -- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
17 mkIface, -- Build a ModIface from a ModGuts,
18 -- including computing version information
22 writeIfaceFile, -- Write the interface file
24 checkOldIface, -- See if recompilation is required, by
25 -- comparing version information
27 tyThingToIfaceDecl -- Converting things to their Iface equivalents
31 -----------------------------------------------
32 MkIface.lhs deals with versioning
33 -----------------------------------------------
35 Here's the version-related info in an interface file
37 module Foo 8 -- module-version
38 3 -- export-list-version
40 Usages: -- Version info for what this compilation of Foo imported
41 Baz 3 -- Module version
42 [4] -- The export-list version if Foo depended on it
43 (g,2) -- Function and its version
44 (T,1) -- Type and its version
46 <version> f :: Int -> Int {- Unfolding: \x -> Wib.t[2] x -}
47 -- The [2] says that f's unfolding
48 -- mentions verison 2 of Wib.t
50 -----------------------------------------------
52 -----------------------------------------------
55 * In the mi_usages information in an interface, we record the
56 version number of each free variable of the module
58 * In mkIface, we compute the version number of each exported thing A.f
59 by comparing its A.f's info with its new info, and bumping its
60 version number if it differs. If A.f mentions B.g, and B.g's version
61 number has changed, then we count A.f as having changed too.
63 * In checkOldIface we compare the mi_usages for the module with
64 the actual version info for all each thing recorded in mi_usages
69 We count A.f as changing if its fixity changes
73 If a rule changes, we want to recompile any module that might be
74 affected by that rule. For non-orphan rules, this is relatively easy.
75 If module M defines f, and a rule for f, just arrange that the version
76 number for M.f changes if any of the rules for M.f change. Any module
77 that does not depend on M.f can't be affected by the rule-change
80 Orphan rules (ones whose 'head function' is not defined in M) are
81 harder. Here's what we do.
83 * We have a per-module orphan-rule version number which changes if
84 any orphan rule changes. (It's unaffected by non-orphan rules.)
86 * We record usage info for any orphan module 'below' this one,
87 giving the orphan-rule version number. We recompile if this
90 The net effect is that if an orphan rule changes, we recompile every
91 module above it. That's very conservative, but it's devilishly hard
92 to know what it might affect, so we just have to be conservative.
96 In an iface file we have
98 instance Eq a => Eq [a] = dfun29
101 We have a version number for dfun29, covering its unfolding
102 etc. Suppose we are compiling a module M that imports A only
103 indirectly. If typechecking M uses this instance decl, we record the
104 dependency on A.dfun29 as if it were a free variable of the module
105 (via the tcg_inst_usages accumulator). That means that A will appear
106 in M's usage list. If the shape of the instance declaration changes,
107 then so will dfun29's version, triggering a recompilation.
109 Adding an instance declaration, or changing an instance decl that is
110 not currently used, is more tricky. (This really only makes a
111 difference when we have overlapping instance decls, because then the
112 new instance decl might kick in to override the old one.) We handle
113 this in a very similar way that we handle rules above.
115 * For non-orphan instance decls, identify one locally-defined tycon/class
116 mentioned in the decl. Treat the instance decl as part of the defn of that
117 tycon/class, so that if the shape of the instance decl changes, so does the
118 tycon/class; that in turn will force recompilation of anything that uses
121 * For orphan instance decls, act the same way as for orphan rules.
122 Indeed, we use the same global orphan-rule version number.
126 mkUsageInfo figures out what the ``usage information'' for this
127 moudule is; that is, what it must record in its interface file as the
130 We produce a line for every module B below the module, A, currently being
133 to record the fact that A does import B indirectly. This is used to decide
134 to look to look for B.hi rather than B.hi-boot when compiling a module that
135 imports A. This line says that A imports B, but uses nothing in it.
136 So we'll get an early bale-out when compiling A if B's version changes.
138 The usage information records:
141 \item (a) anything reachable from its body code
142 \item (b) any module exported with a @module Foo@
143 \item (c) anything reachable from an exported item
146 Why (b)? Because if @Foo@ changes then this module's export list
147 will change, so we must recompile this module at least as far as
148 making a new interface file --- but in practice that means complete
151 Why (c)? Consider this:
153 module A( f, g ) where | module B( f ) where
154 import B( f ) | f = h 3
158 Here, @B.f@ isn't used in A. Should we nevertheless record @B.f@ in
159 @A@'s usages? Our idea is that we aren't going to touch A.hi if it is
160 *identical* to what it was before. If anything about @B.f@ changes
161 than anyone who imports @A@ should be recompiled in case they use
162 @B.f@ (they'll get an early exit if they don't). So, if anything
163 about @B.f@ changes we'd better make sure that something in A.hi
164 changes, and the convenient way to do that is to record the version
165 number @B.f@ in A.hi in the usage list. If B.f changes that'll force a
166 complete recompiation of A, which is overkill but it's the only way to
167 write a new, slightly different, A.hi.
169 But the example is tricker. Even if @B.f@ doesn't change at all,
170 @B.h@ may do so, and this change may not be reflected in @f@'s version
171 number. But with -O, a module that imports A must be recompiled if
172 @B.h@ changes! So A must record a dependency on @B.h@. So we treat
173 the occurrence of @B.f@ in the export list *just as if* it were in the
174 code of A, and thereby haul in all the stuff reachable from it.
176 *** Conclusion: if A mentions B.f in its export list,
177 behave just as if A mentioned B.f in its source code,
178 and slurp in B.f and all its transitive closure ***
180 [NB: If B was compiled with -O, but A isn't, we should really *still*
181 haul in all the unfoldings for B, in case the module that imports A *is*
182 compiled with -O. I think this is the case.]
186 #include "HsVersions.h"
219 import PackageConfig hiding ( Version )
221 import BasicTypes hiding ( SuccessFlag(..) )
223 import Util hiding ( eqListBy )
236 %************************************************************************
238 \subsection{Completing an interface}
240 %************************************************************************
244 -> Maybe ModIface -- The old interface, if we have it
245 -> ModDetails -- The trimmed, tidied interface
246 -> ModGuts -- Usages, deprecations, etc
247 -> IO (ModIface, -- The new one, complete with decls and versions
248 Bool) -- True <=> there was an old Iface, and the new one
249 -- is identical, so no need to write it
251 mkIface hsc_env maybe_old_iface mod_details
252 ModGuts{ mg_module = this_mod,
254 mg_used_names = used_names,
256 mg_dir_imps = dir_imp_mods,
257 mg_rdr_env = rdr_env,
258 mg_fix_env = fix_env,
259 mg_deprecs = deprecs,
260 mg_hpc_info = hpc_info }
261 = mkIface_ hsc_env maybe_old_iface
262 this_mod is_boot used_names deps rdr_env
263 fix_env deprecs hpc_info dir_imp_mods mod_details
265 -- | make an interface from the results of typechecking only. Useful
266 -- for non-optimising compilation, or where we aren't generating any
267 -- object code at all ('HscNothing').
269 -> Maybe ModIface -- The old interface, if we have it
270 -> ModDetails -- gotten from mkBootModDetails, probably
271 -> TcGblEnv -- Usages, deprecations, etc
274 mkIfaceTc hsc_env maybe_old_iface mod_details
275 tc_result@TcGblEnv{ tcg_mod = this_mod,
277 tcg_imports = imports,
278 tcg_rdr_env = rdr_env,
279 tcg_fix_env = fix_env,
280 tcg_deprecs = deprecs,
281 tcg_hpc = other_hpc_info
284 used_names <- mkUsedNames tc_result
285 deps <- mkDependencies tc_result
286 let hpc_info = emptyHpcInfo other_hpc_info
287 mkIface_ hsc_env maybe_old_iface
288 this_mod (isHsBoot hsc_src) used_names deps rdr_env
289 fix_env deprecs hpc_info (imp_mods imports) mod_details
292 mkUsedNames :: TcGblEnv -> IO NameSet
294 TcGblEnv{ tcg_inst_uses = dfun_uses_var,
298 dfun_uses <- readIORef dfun_uses_var -- What dfuns are used
299 return (allUses dus `unionNameSets` dfun_uses)
301 mkDependencies :: TcGblEnv -> IO Dependencies
303 TcGblEnv{ tcg_mod = mod,
304 tcg_imports = imports,
308 th_used <- readIORef th_var -- Whether TH is used
310 dep_mods = eltsUFM (delFromUFM (imp_dep_mods imports) (moduleName mod))
311 -- M.hi-boot can be in the imp_dep_mods, but we must remove
312 -- it before recording the modules on which this one depends!
313 -- (We want to retain M.hi-boot in imp_dep_mods so that
314 -- loadHiBootInterface can see if M's direct imports depend
315 -- on M.hi-boot, and hence that we should do the hi-boot consistency
318 dir_imp_mods = imp_mods imports
320 -- Modules don't compare lexicographically usually,
321 -- but we want them to do so here.
322 le_mod :: Module -> Module -> Bool
323 le_mod m1 m2 = moduleNameFS (moduleName m1)
324 <= moduleNameFS (moduleName m2)
326 le_dep_mod :: (ModuleName, IsBootInterface)
327 -> (ModuleName, IsBootInterface) -> Bool
328 le_dep_mod (m1,_) (m2,_) = moduleNameFS m1 <= moduleNameFS m2
331 pkgs | th_used = insertList thPackageId (imp_dep_pkgs imports)
332 | otherwise = imp_dep_pkgs imports
334 return Deps { dep_mods = sortLe le_dep_mod dep_mods,
335 dep_pkgs = sortLe (<=) pkgs,
336 dep_orphs = sortLe le_mod (imp_orphs imports),
337 dep_finsts = sortLe le_mod (imp_finsts imports) }
338 -- sort to get into canonical order
341 mkIface_ hsc_env maybe_old_iface
342 this_mod is_boot used_names deps rdr_env fix_env src_deprecs hpc_info
344 ModDetails{ md_insts = insts,
345 md_fam_insts = fam_insts,
347 md_vect_info = vect_info,
349 md_exports = exports }
350 -- NB: notice that mkIface does not look at the bindings
351 -- only at the TypeEnv. The previous Tidy phase has
352 -- put exactly the info into the TypeEnv that we want
353 -- to expose in the interface
355 = do {eps <- hscEPS hsc_env
357 ; usages <- mkUsageInfo hsc_env dir_imp_mods (dep_mods deps) used_names
359 ; let { entities = typeEnvElts type_env ;
360 decls = [ tyThingToIfaceDecl entity
361 | entity <- entities,
362 let name = getName entity,
363 not (isImplicitTyThing entity),
364 -- No implicit Ids and class tycons in the interface file
365 not (isWiredInName name),
366 -- Nor wired-in things; the compiler knows about them anyhow
367 nameIsLocalOrFrom this_mod name ]
368 -- Sigh: see Note [Root-main Id] in TcRnDriver
370 ; fixities = [(occ,fix) | FixItem occ fix <- nameEnvElts fix_env]
371 ; deprecs = src_deprecs
372 ; iface_rules = map (coreRuleToIfaceRule this_mod) rules
373 ; iface_insts = map instanceToIfaceInst insts
374 ; iface_fam_insts = map famInstToIfaceFamInst fam_insts
375 ; iface_vect_info = flattenVectInfo vect_info
377 ; intermediate_iface = ModIface {
378 mi_module = this_mod,
382 mi_exports = mkIfaceExports exports,
384 -- Sort these lexicographically, so that
385 -- the result is stable across compilations
386 mi_insts = sortLe le_inst iface_insts,
387 mi_fam_insts= sortLe le_fam_inst iface_fam_insts,
388 mi_rules = sortLe le_rule iface_rules,
390 mi_vect_info = iface_vect_info,
392 mi_fixities = fixities,
393 mi_deprecs = deprecs,
394 mi_globals = Just rdr_env,
396 -- Left out deliberately: filled in by addVersionInfo
397 mi_mod_vers = initialVersion,
398 mi_exp_vers = initialVersion,
399 mi_rule_vers = initialVersion,
400 mi_orphan = False, -- Always set by addVersionInfo, but
401 -- it's a strict field, so we can't omit it.
402 mi_finsts = False, -- Ditto
403 mi_decls = deliberatelyOmitted "decls",
404 mi_ver_fn = deliberatelyOmitted "ver_fn",
405 mi_hpc = isHpcUsed hpc_info,
407 -- And build the cached values
408 mi_dep_fn = mkIfaceDepCache deprecs,
409 mi_fix_fn = mkIfaceFixCache fixities }
411 -- Add version information
412 ; ext_ver_fn = mkParentVerFun hsc_env eps
413 ; (new_iface, no_change_at_all, pp_diffs, pp_orphs)
414 = {-# SCC "versioninfo" #-}
415 addVersionInfo ext_ver_fn maybe_old_iface
416 intermediate_iface decls
420 ; when (isJust pp_orphs && dopt Opt_WarnOrphans dflags)
421 (printDump (expectJust "mkIface" pp_orphs))
422 ; when (dopt Opt_D_dump_hi_diffs dflags) (printDump pp_diffs)
423 ; dumpIfSet_dyn dflags Opt_D_dump_hi "FINAL INTERFACE"
424 (pprModIface new_iface)
426 ; return (new_iface, no_change_at_all) }
428 r1 `le_rule` r2 = ifRuleName r1 <= ifRuleName r2
429 i1 `le_inst` i2 = ifDFun i1 `le_occ` ifDFun i2
430 i1 `le_fam_inst` i2 = ifFamInstTcName i1 `le_occ` ifFamInstTcName i2
432 le_occ :: Name -> Name -> Bool
433 -- Compare lexicographically by OccName, *not* by unique, because
434 -- the latter is not stable across compilations
435 le_occ n1 n2 = nameOccName n1 <= nameOccName n2
437 dflags = hsc_dflags hsc_env
438 deliberatelyOmitted x = panic ("Deliberately omitted: " ++ x)
439 ifFamInstTcName = ifaceTyConName . ifFamInstTyCon
441 flattenVectInfo (VectInfo { vectInfoVar = vVar
442 , vectInfoTyCon = vTyCon
445 ifaceVectInfoVar = [ Var.varName v
446 | (v, _) <- varEnvElts vVar],
447 ifaceVectInfoTyCon = [ tyConName t
448 | (t, t_v) <- nameEnvElts vTyCon
450 ifaceVectInfoTyConReuse = [ tyConName t
451 | (t, t_v) <- nameEnvElts vTyCon
455 -----------------------------
456 writeIfaceFile :: DynFlags -> ModLocation -> ModIface -> IO ()
457 writeIfaceFile dflags location new_iface
458 = do createDirectoryHierarchy (directoryOf hi_file_path)
459 writeBinIface dflags hi_file_path new_iface
460 where hi_file_path = ml_hi_file location
463 -- -----------------------------------------------------------------------------
464 -- Look up parents and versions of Names
466 -- This is like a global version of the mi_ver_fn field in each ModIface.
467 -- Given a Name, it finds the ModIface, and then uses mi_ver_fn to get
468 -- the parent and version info.
471 :: HscEnv -- needed to look up versions
472 -> ExternalPackageState -- ditto
473 -> (Name -> (OccName,Version))
474 mkParentVerFun hsc_env eps
477 mod = nameModule name
478 occ = nameOccName name
479 iface = lookupIfaceByModule (hsc_dflags hsc_env) hpt pit mod `orElse`
480 pprPanic "lookupVers2" (ppr mod <+> ppr occ)
482 mi_ver_fn iface occ `orElse`
483 pprPanic "lookupVers1" (ppr mod <+> ppr occ)
485 hpt = hsc_HPT hsc_env
488 -----------------------------------------------------------------------------
489 -- Compute version numbers for local decls
492 :: (Name -> (OccName,Version)) -- lookup parents and versions of names
493 -> Maybe ModIface -- The old interface, read from M.hi
494 -> ModIface -- The new interface (lacking decls)
495 -> [IfaceDecl] -- The new decls
496 -> (ModIface, -- Updated interface
497 Bool, -- True <=> no changes at all; no need to write Iface
499 Maybe SDoc) -- Warnings about orphans
501 addVersionInfo ver_fn Nothing new_iface new_decls
502 -- No old interface, so definitely write a new one!
503 = (new_iface { mi_orphan = not (null orph_insts && null orph_rules)
504 , mi_finsts = not . null $ mi_fam_insts new_iface
505 , mi_decls = [(initialVersion, decl) | decl <- new_decls]
506 , mi_ver_fn = mkIfaceVerCache (zip (repeat initialVersion)
510 ptext SLIT("No old interface file"),
511 pprOrphans orph_insts orph_rules)
513 orph_insts = filter (isNothing . ifInstOrph) (mi_insts new_iface)
514 orph_rules = filter (isNothing . ifRuleOrph) (mi_rules new_iface)
516 addVersionInfo ver_fn (Just old_iface@(ModIface {
517 mi_mod_vers = old_mod_vers,
518 mi_exp_vers = old_exp_vers,
519 mi_rule_vers = old_rule_vers,
520 mi_decls = old_decls,
521 mi_ver_fn = old_decl_vers,
522 mi_fix_fn = old_fixities }))
523 new_iface@(ModIface { mi_fix_fn = new_fixities })
526 = (old_iface, True, ptext SLIT("Interface file unchanged"), pp_orphs)
528 = (final_iface, False, vcat [ptext SLIT("Interface file has changed"),
529 nest 2 pp_diffs], pp_orphs)
531 final_iface = new_iface {
532 mi_mod_vers = bump_unless no_output_change old_mod_vers,
533 mi_exp_vers = bump_unless no_export_change old_exp_vers,
534 mi_rule_vers = bump_unless no_rule_change old_rule_vers,
535 mi_orphan = not (null new_orph_rules && null new_orph_insts),
536 mi_finsts = not . null $ mi_fam_insts new_iface,
537 mi_decls = decls_w_vers,
538 mi_ver_fn = mkIfaceVerCache decls_w_vers }
540 decls_w_vers = [(add_vers decl, decl) | decl <- new_decls]
543 (old_non_orph_insts, old_orph_insts) =
544 mkOrphMap ifInstOrph (mi_insts old_iface)
545 (new_non_orph_insts, new_orph_insts) =
546 mkOrphMap ifInstOrph (mi_insts new_iface)
547 old_fam_insts = mi_fam_insts old_iface
548 new_fam_insts = mi_fam_insts new_iface
549 same_insts occ = eqMaybeBy (eqListBy eqIfInst)
550 (lookupOccEnv old_non_orph_insts occ)
551 (lookupOccEnv new_non_orph_insts occ)
553 (old_non_orph_rules, old_orph_rules) =
554 mkOrphMap ifRuleOrph (mi_rules old_iface)
555 (new_non_orph_rules, new_orph_rules) =
556 mkOrphMap ifRuleOrph (mi_rules new_iface)
557 same_rules occ = eqMaybeBy (eqListBy eqIfRule)
558 (lookupOccEnv old_non_orph_rules occ)
559 (lookupOccEnv new_non_orph_rules occ)
561 -- Computing what changed
562 no_output_change = no_decl_change && no_rule_change &&
563 no_export_change && no_deprec_change
564 no_export_change = mi_exports new_iface == mi_exports old_iface
566 no_decl_change = isEmptyOccSet changed_occs
567 no_rule_change = not (changedWrtNames changed_occs (eqListBy eqIfRule old_orph_rules new_orph_rules)
568 || changedWrtNames changed_occs (eqListBy eqIfInst old_orph_insts new_orph_insts)
569 || changedWrtNames changed_occs (eqListBy eqIfFamInst old_fam_insts new_fam_insts))
570 no_deprec_change = mi_deprecs new_iface == mi_deprecs old_iface
572 -- If the usages havn't changed either, we don't need to write the interface file
573 no_other_changes = mi_usages new_iface == mi_usages old_iface &&
574 mi_deps new_iface == mi_deps old_iface &&
575 mi_hpc new_iface == mi_hpc old_iface
576 no_change_at_all = no_output_change && no_other_changes
578 pp_diffs = vcat [pp_change no_export_change "Export list"
579 (ppr old_exp_vers <+> arrow <+> ppr (mi_exp_vers final_iface)),
580 pp_change no_rule_change "Rules"
581 (ppr old_rule_vers <+> arrow <+> ppr (mi_rule_vers final_iface)),
582 pp_change no_deprec_change "Deprecations" empty,
583 pp_change no_other_changes "Usages" empty,
585 pp_change True what info = empty
586 pp_change False what info = text what <+> ptext SLIT("changed") <+> info
589 old_decl_env = mkOccEnv [(ifName decl, decl) | (_,decl) <- old_decls]
590 same_fixity n = bool (old_fixities n == new_fixities n)
593 -- Adding version info
594 new_version = bumpVersion old_mod_vers
595 -- Start from the old module version, not from
596 -- zero so that if you remove f, and then add
597 -- it again, you don't thereby reduce f's
600 add_vers decl | occ `elemOccSet` changed_occs = new_version
601 | otherwise = snd (expectJust "add_vers" (old_decl_vers occ))
602 -- If it's unchanged, there jolly well
603 where -- should be an old version number
607 -- Deciding which declarations have changed
609 -- For each local decl, the IfaceEq gives the list of things that
610 -- must be unchanged for the declaration as a whole to be unchanged.
611 eq_info :: [(OccName, IfaceEq)]
612 eq_info = map check_eq new_decls
614 | Just old_decl <- lookupOccEnv old_decl_env occ
615 = (occ, new_decl `eqIfDecl` old_decl &&& eq_indirects new_decl)
616 | otherwise {- No corresponding old decl -}
619 occ = ifName new_decl
621 eq_indirects :: IfaceDecl -> IfaceEq
622 -- When seeing if two decls are the same, remember to
623 -- check whether any relevant fixity or rules have changed
624 eq_indirects (IfaceId {ifName = occ}) = eq_ind_occ occ
625 eq_indirects (IfaceClass {ifName = cls_occ, ifSigs = sigs})
626 = same_insts cls_occ &&&
627 eq_ind_occs [op | IfaceClassOp op _ _ <- sigs]
628 eq_indirects (IfaceData {ifName = tc_occ, ifCons = cons})
629 = same_insts tc_occ &&& same_fixity tc_occ &&& -- The TyCon can have a fixity too
630 eq_ind_occs (map ifConOcc (visibleIfConDecls cons))
631 eq_indirects other = Equal -- Synonyms and foreign declarations
633 eq_ind_occ :: OccName -> IfaceEq -- For class ops and Ids; check fixity and rules
634 eq_ind_occ occ = same_fixity occ &&& same_rules occ
635 eq_ind_occs = foldr ((&&&) . eq_ind_occ) Equal
637 -- The Occs of declarations that changed.
638 changed_occs :: OccSet
639 changed_occs = computeChangedOccs ver_fn (mi_module new_iface)
640 (mi_usages old_iface) eq_info
644 pp_decl_diffs :: SDoc -- Nothing => no changes
646 | isEmptyOccSet changed_occs = empty
648 = vcat [ptext SLIT("Changed occs:") <+> ppr (occSetElts changed_occs),
649 ptext SLIT("Version change for these decls:"),
650 nest 2 (vcat (map show_change new_decls))]
652 eq_env = mkOccEnv eq_info
654 | not (occ `elemOccSet` changed_occs) = empty
656 = vcat [ppr occ <+> ppr (old_decl_vers occ) <+> arrow <+> ppr new_version,
659 occ = ifName new_decl
660 why = case lookupOccEnv eq_env occ of
661 Just (EqBut names) -> sep [ppr occ <> colon, ptext SLIT("Free vars (only) changed:") <> ppr names,
662 nest 2 (braces (fsep (map ppr (occSetElts
663 (occs `intersectOccSet` changed_occs)))))]
664 where occs = mkOccSet (map nameOccName (nameSetToList names))
666 | Just old_decl <- lookupOccEnv old_decl_env occ
667 -> vcat [ptext SLIT("Old:") <+> ppr old_decl,
668 ptext SLIT("New:") <+> ppr new_decl]
670 -> ppr occ <+> ptext SLIT("only in new interface")
671 other -> pprPanic "MkIface.show_change" (ppr occ)
673 pp_orphs = pprOrphans new_orph_insts new_orph_rules
676 pprOrphans insts rules
677 | null insts && null rules = Nothing
680 if null insts then empty else
681 hang (ptext SLIT("Warning: orphan instances:"))
682 2 (vcat (map ppr insts)),
683 if null rules then empty else
684 hang (ptext SLIT("Warning: orphan rules:"))
685 2 (vcat (map ppr rules))
689 :: (Name -> (OccName,Version)) -- get parents and versions
690 -> Module -- This module
691 -> [Usage] -- Usages from old iface
692 -> [(OccName, IfaceEq)] -- decl names, equality conditions
693 -> OccSet -- set of things that have changed
694 computeChangedOccs ver_fn this_module old_usages eq_info
695 = foldl add_changes emptyOccSet (stronglyConnComp edges)
698 -- return True if an external name has changed
699 name_changed :: Name -> Bool
701 | Just ents <- lookupUFM usg_modmap (moduleName mod)
702 = case lookupUFM ents parent_occ of
703 Nothing -> pprPanic "computeChangedOccs" (ppr nm)
704 Just v -> v < new_version
705 | otherwise = False -- must be in another package
708 (parent_occ, new_version) = ver_fn nm
710 -- Turn the usages from the old ModIface into a mapping
711 usg_modmap = listToUFM [ (usg_mod usg, listToUFM (usg_entities usg))
712 | usg <- old_usages ]
714 get_local_eq_info :: GenIfaceEq NameSet -> GenIfaceEq OccSet
715 get_local_eq_info Equal = Equal
716 get_local_eq_info NotEqual = NotEqual
717 get_local_eq_info (EqBut ns) = foldNameSet f Equal ns
718 where f name eq | nameModule name == this_module =
719 EqBut (unitOccSet (nameOccName name)) `and_occifeq` eq
720 | name_changed name = NotEqual
723 local_eq_infos = mapSnd get_local_eq_info eq_info
725 edges :: [((OccName, OccIfaceEq), Unique, [Unique])]
726 edges = [ (node, getUnique occ, map getUnique occs)
727 | node@(occ, iface_eq) <- local_eq_infos
728 , let occs = case iface_eq of
729 EqBut occ_set -> occSetElts occ_set
732 -- Changes in declarations
733 add_changes :: OccSet -> SCC (OccName, OccIfaceEq) -> OccSet
734 add_changes so_far (AcyclicSCC (occ, iface_eq))
735 | changedWrt so_far iface_eq -- This one has changed
736 = extendOccSet so_far occ
737 add_changes so_far (CyclicSCC pairs)
738 | changedWrt so_far (foldr1 and_occifeq iface_eqs)
739 -- One of this group has changed
740 = extendOccSetList so_far occs
741 where (occs, iface_eqs) = unzip pairs
742 add_changes so_far other = so_far
744 type OccIfaceEq = GenIfaceEq OccSet
746 changedWrt :: OccSet -> OccIfaceEq -> Bool
747 changedWrt so_far Equal = False
748 changedWrt so_far NotEqual = True
749 changedWrt so_far (EqBut kids) = so_far `intersectsOccSet` kids
751 changedWrtNames :: OccSet -> IfaceEq -> Bool
752 changedWrtNames so_far Equal = False
753 changedWrtNames so_far NotEqual = True
754 changedWrtNames so_far (EqBut kids) =
755 so_far `intersectsOccSet` mkOccSet (map nameOccName (nameSetToList kids))
757 and_occifeq :: OccIfaceEq -> OccIfaceEq -> OccIfaceEq
758 Equal `and_occifeq` x = x
759 NotEqual `and_occifeq` x = NotEqual
760 EqBut nms `and_occifeq` Equal = EqBut nms
761 EqBut nms `and_occifeq` NotEqual = NotEqual
762 EqBut nms1 `and_occifeq` EqBut nms2 = EqBut (nms1 `unionOccSets` nms2)
764 ----------------------
765 -- mkOrphMap partitions instance decls or rules into
766 -- (a) an OccEnv for ones that are not orphans,
767 -- mapping the local OccName to a list of its decls
768 -- (b) a list of orphan decls
769 mkOrphMap :: (decl -> Maybe OccName) -- (Just occ) for a non-orphan decl, keyed by occ
770 -- Nothing for an orphan decl
771 -> [decl] -- Sorted into canonical order
772 -> (OccEnv [decl], -- Non-orphan decls associated with their key;
773 -- each sublist in canonical order
774 [decl]) -- Orphan decls; in canonical order
775 mkOrphMap get_key decls
776 = foldl go (emptyOccEnv, []) decls
778 go (non_orphs, orphs) d
779 | Just occ <- get_key d
780 = (extendOccEnv_C (\ ds _ -> d:ds) non_orphs occ [d], orphs)
781 | otherwise = (non_orphs, d:orphs)
783 ----------------------
784 bump_unless :: Bool -> Version -> Version
785 bump_unless True v = v -- True <=> no change
786 bump_unless False v = bumpVersion v
790 %*********************************************************
792 \subsection{Keeping track of what we've slurped, and version numbers}
794 %*********************************************************
798 mkUsageInfo :: HscEnv
799 -> ModuleEnv (Module, [(ModuleName, Bool, SrcSpan)])
800 -> [(ModuleName, IsBootInterface)]
801 -> NameSet -> IO [Usage]
802 mkUsageInfo hsc_env dir_imp_mods dep_mods used_names
803 = do { eps <- hscEPS hsc_env
804 ; let usages = mk_usage_info (eps_PIT eps) hsc_env
805 dir_imp_mods dep_mods used_names
806 ; usages `seqList` return usages }
807 -- seq the list of Usages returned: occasionally these
808 -- don't get evaluated for a while and we can end up hanging on to
809 -- the entire collection of Ifaces.
811 mk_usage_info :: PackageIfaceTable
813 -> ModuleEnv (Module, [(ModuleName, Bool, SrcSpan)])
814 -> [(ModuleName, IsBootInterface)]
817 mk_usage_info pit hsc_env dir_imp_mods dep_mods used_names
818 = mapCatMaybes mkUsage dep_mods
819 -- ToDo: do we need to sort into canonical order?
821 hpt = hsc_HPT hsc_env
822 dflags = hsc_dflags hsc_env
824 -- ent_map groups together all the things imported and used
825 -- from a particular module in this package
826 ent_map :: ModuleEnv [OccName]
827 ent_map = foldNameSet add_mv emptyModuleEnv used_names
829 | isWiredInName name = mv_map -- ignore wired-in names
831 = case nameModule_maybe name of
832 Nothing -> mv_map -- ignore internal names
833 Just mod -> extendModuleEnv_C add_item mv_map mod [occ]
835 occ = nameOccName name
836 add_item occs _ = occ:occs
838 depend_on_exports mod = case lookupModuleEnv dir_imp_mods mod of
839 Just (_, xs) -> any (\(_, no_imp, _) -> not no_imp) xs
842 -- We want to create a Usage for a home module if
843 -- a) we used something from; has something in used_names
844 -- b) we imported all of it, even if we used nothing from it
845 -- (need to recompile if its export list changes: export_vers)
846 -- c) is a home-package orphan or family-instance module (need to
847 -- recompile if its instance decls change: rules_vers)
848 mkUsage :: (ModuleName, IsBootInterface) -> Maybe Usage
849 mkUsage (mod_name, _)
850 | isNothing maybe_iface -- We can't depend on it if we didn't
851 || (null used_occs -- load its interface.
852 && isNothing export_vers
855 = Nothing -- Record no usage info
858 = Just (Usage { usg_name = mod_name,
860 usg_exports = export_vers,
861 usg_entities = fmToList ent_vers,
862 usg_rules = rules_vers })
864 maybe_iface = lookupIfaceByModule dflags hpt pit mod
865 -- In one-shot mode, the interfaces for home-package
866 -- modules accumulate in the PIT not HPT. Sigh.
868 mod = mkModule (thisPackage dflags) mod_name
870 Just iface = maybe_iface
871 orphan_mod = mi_orphan iface
872 finsts_mod = mi_finsts iface
873 version_env = mi_ver_fn iface
874 mod_vers = mi_mod_vers iface
875 rules_vers = mi_rule_vers iface
876 export_vers | depend_on_exports mod = Just (mi_exp_vers iface)
877 | otherwise = Nothing
879 used_occs = lookupModuleEnv ent_map mod `orElse` []
881 -- Making a FiniteMap here ensures that (a) we remove duplicates
882 -- when we have usages on several subordinates of a single parent,
883 -- and (b) that the usages emerge in a canonical order, which
884 -- is why we use FiniteMap rather than OccEnv: FiniteMap works
885 -- using Ord on the OccNames, which is a lexicographic ordering.
886 ent_vers :: FiniteMap OccName Version
887 ent_vers = listToFM (map lookup_occ used_occs)
890 case version_env occ of
891 Nothing -> pprTrace "hmm, strange" (ppr mod <+> ppr occ) $
892 (occ, initialVersion) -- does this ever happen?
893 Just (parent, version) -> (parent, version)
897 mkIfaceExports :: [AvailInfo]
898 -> [(Module, [GenAvailInfo OccName])]
899 -- Group by module and sort by occurrence
900 -- This keeps the list in canonical order
901 mkIfaceExports exports
902 = [ (mod, eltsFM avails)
903 | (mod, avails) <- fmToList groupFM
906 -- Group by the module where the exported entities are defined
907 -- (which may not be the same for all Names in an Avail)
908 -- Deliberately use FiniteMap rather than UniqFM so we
909 -- get a canonical ordering
910 groupFM :: ModuleEnv (FiniteMap FastString (GenAvailInfo OccName))
911 groupFM = foldl add emptyModuleEnv exports
913 add_one :: ModuleEnv (FiniteMap FastString (GenAvailInfo OccName))
914 -> Module -> GenAvailInfo OccName
915 -> ModuleEnv (FiniteMap FastString (GenAvailInfo OccName))
916 add_one env mod avail
917 = extendModuleEnv_C plusFM env mod
918 (unitFM (occNameFS (availName avail)) avail)
920 -- NB: we should not get T(X) and T(Y) in the export list
921 -- else the plusFM will simply discard one! They
922 -- should have been combined by now.
924 = add_one env (nameModule n) (Avail (nameOccName n))
926 add env (AvailTC tc ns)
927 = foldl add_for_mod env mods
929 tc_occ = nameOccName tc
930 mods = nub (map nameModule ns)
931 -- Usually just one, but see Note [Original module]
934 = add_one env mod (AvailTC tc_occ (sort names_from_mod))
935 -- NB. sort the children, we need a canonical order
937 names_from_mod = [nameOccName n | n <- ns, nameModule n == mod]
940 Note [Orignal module]
941 ~~~~~~~~~~~~~~~~~~~~~
943 module X where { data family T }
944 module Y( T(..) ) where { import X; data instance T Int = MkT Int }
945 The exported Avail from Y will look like
948 - only MkT is brought into scope by the data instance;
949 - but the parent (used for grouping and naming in T(..) exports) is X.T
950 - and in this case we export X.T too
952 In the result of MkIfaceExports, the names are grouped by defining module,
953 so we may need to split up a single Avail into multiple ones.
956 %************************************************************************
958 Load the old interface file for this module (unless
959 we have it aleady), and check whether it is up to date
962 %************************************************************************
965 checkOldIface :: HscEnv
967 -> Bool -- Source unchanged
968 -> Maybe ModIface -- Old interface from compilation manager, if any
969 -> IO (RecompileRequired, Maybe ModIface)
971 checkOldIface hsc_env mod_summary source_unchanged maybe_iface
972 = do { showPass (hsc_dflags hsc_env)
973 ("Checking old interface for " ++
974 showSDoc (ppr (ms_mod mod_summary))) ;
976 ; initIfaceCheck hsc_env $
977 check_old_iface hsc_env mod_summary source_unchanged maybe_iface
980 check_old_iface hsc_env mod_summary source_unchanged maybe_iface
981 = do -- CHECK WHETHER THE SOURCE HAS CHANGED
982 { ifM (not source_unchanged)
983 (traceHiDiffs (nest 4 (text "Source file changed or recompilation check turned off")))
985 -- If the source has changed and we're in interactive mode, avoid reading
986 -- an interface; just return the one we might have been supplied with.
987 ; let dflags = hsc_dflags hsc_env
988 ; if not (isObjectTarget (hscTarget dflags)) && not source_unchanged then
989 return (outOfDate, maybe_iface)
991 case maybe_iface of {
992 Just old_iface -> do -- Use the one we already have
993 { traceIf (text "We already have the old interface for" <+> ppr (ms_mod mod_summary))
994 ; recomp <- checkVersions hsc_env source_unchanged mod_summary old_iface
995 ; return (recomp, Just old_iface) }
999 -- Try and read the old interface for the current module
1000 -- from the .hi file left from the last time we compiled it
1001 { let iface_path = msHiFilePath mod_summary
1002 ; read_result <- readIface (ms_mod mod_summary) iface_path False
1003 ; case read_result of {
1004 Failed err -> do -- Old interface file not found, or garbled; give up
1005 { traceIf (text "FYI: cannot read old interface file:"
1007 ; return (outOfDate, Nothing) }
1009 ; Succeeded iface -> do
1011 -- We have got the old iface; check its versions
1012 { traceIf (text "Read the interface file" <+> text iface_path)
1013 ; recomp <- checkVersions hsc_env source_unchanged mod_summary iface
1014 ; returnM (recomp, Just iface)
1019 @recompileRequired@ is called from the HscMain. It checks whether
1020 a recompilation is required. It needs access to the persistent state,
1021 finder, etc, because it may have to load lots of interface files to
1022 check their versions.
1025 type RecompileRequired = Bool
1026 upToDate = False -- Recompile not required
1027 outOfDate = True -- Recompile required
1029 checkVersions :: HscEnv
1030 -> Bool -- True <=> source unchanged
1032 -> ModIface -- Old interface
1033 -> IfG RecompileRequired
1034 checkVersions hsc_env source_unchanged mod_summary iface
1035 | not source_unchanged
1038 = do { traceHiDiffs (text "Considering whether compilation is required for" <+>
1039 ppr (mi_module iface) <> colon)
1041 ; recomp <- checkDependencies hsc_env mod_summary iface
1042 ; if recomp then return outOfDate else do {
1044 -- Source code unchanged and no errors yet... carry on
1046 -- First put the dependent-module info, read from the old interface, into the envt,
1047 -- so that when we look for interfaces we look for the right one (.hi or .hi-boot)
1049 -- It's just temporary because either the usage check will succeed
1050 -- (in which case we are done with this module) or it'll fail (in which
1051 -- case we'll compile the module from scratch anyhow).
1053 -- We do this regardless of compilation mode, although in --make mode
1054 -- all the dependent modules should be in the HPT already, so it's
1056 updateEps_ $ \eps -> eps { eps_is_boot = mod_deps }
1058 ; let this_pkg = thisPackage (hsc_dflags hsc_env)
1059 ; checkList [checkModUsage this_pkg u | u <- mi_usages iface]
1062 -- This is a bit of a hack really
1063 mod_deps :: ModuleNameEnv (ModuleName, IsBootInterface)
1064 mod_deps = mkModDeps (dep_mods (mi_deps iface))
1067 -- If the direct imports of this module are resolved to targets that
1068 -- are not among the dependencies of the previous interface file,
1069 -- then we definitely need to recompile. This catches cases like
1070 -- - an exposed package has been upgraded
1071 -- - we are compiling with different package flags
1072 -- - a home module that was shadowing a package module has been removed
1073 -- - a new home module has been added that shadows a package module
1076 -- Returns True if recompilation is required.
1077 checkDependencies :: HscEnv -> ModSummary -> ModIface -> IfG RecompileRequired
1078 checkDependencies hsc_env summary iface
1079 = orM (map dep_missing (ms_imps summary ++ ms_srcimps summary))
1081 prev_dep_mods = dep_mods (mi_deps iface)
1082 prev_dep_pkgs = dep_pkgs (mi_deps iface)
1084 this_pkg = thisPackage (hsc_dflags hsc_env)
1086 orM = foldr f (return False)
1087 where f m rest = do b <- m; if b then return True else rest
1089 dep_missing (L _ mod) = do
1090 find_res <- ioToIOEnv $ findImportedModule hsc_env mod Nothing
1094 -> if moduleName mod `notElem` map fst prev_dep_mods
1095 then do traceHiDiffs $
1096 text "imported module " <> quotes (ppr mod) <>
1097 text " not among previous dependencies"
1102 -> if pkg `notElem` prev_dep_pkgs
1103 then do traceHiDiffs $
1104 text "imported module " <> quotes (ppr mod) <>
1105 text " is from package " <> quotes (ppr pkg) <>
1106 text ", which is not among previous dependencies"
1110 where pkg = modulePackageId mod
1111 _otherwise -> return outOfDate
1113 checkModUsage :: PackageId ->Usage -> IfG RecompileRequired
1114 -- Given the usage information extracted from the old
1115 -- M.hi file for the module being compiled, figure out
1116 -- whether M needs to be recompiled.
1118 checkModUsage this_pkg (Usage { usg_name = mod_name, usg_mod = old_mod_vers,
1119 usg_rules = old_rule_vers,
1120 usg_exports = maybe_old_export_vers,
1121 usg_entities = old_decl_vers })
1122 = -- Load the imported interface is possible
1124 doc_str = sep [ptext SLIT("need version info for"), ppr mod_name]
1126 traceHiDiffs (text "Checking usages for module" <+> ppr mod_name) `thenM_`
1129 mod = mkModule this_pkg mod_name
1131 loadInterface doc_str mod ImportBySystem `thenM` \ mb_iface ->
1132 -- Load the interface, but don't complain on failure;
1133 -- Instead, get an Either back which we can test
1136 Failed exn -> (out_of_date (sep [ptext SLIT("Can't find version number for module"),
1138 -- Couldn't find or parse a module mentioned in the
1139 -- old interface file. Don't complain -- it might just be that
1140 -- the current module doesn't need that import and it's been deleted
1144 new_mod_vers = mi_mod_vers iface
1145 new_decl_vers = mi_ver_fn iface
1146 new_export_vers = mi_exp_vers iface
1147 new_rule_vers = mi_rule_vers iface
1150 checkModuleVersion old_mod_vers new_mod_vers `thenM` \ recompile ->
1151 if not recompile then
1155 -- CHECK EXPORT LIST
1156 if checkExportList maybe_old_export_vers new_export_vers then
1157 out_of_date_vers (ptext SLIT(" Export list changed"))
1158 (expectJust "checkModUsage" maybe_old_export_vers)
1163 if old_rule_vers /= new_rule_vers then
1164 out_of_date_vers (ptext SLIT(" Rules changed"))
1165 old_rule_vers new_rule_vers
1168 -- CHECK ITEMS ONE BY ONE
1169 checkList [checkEntityUsage new_decl_vers u | u <- old_decl_vers] `thenM` \ recompile ->
1171 returnM outOfDate -- This one failed, so just bail out now
1173 up_to_date (ptext SLIT(" Great! The bits I use are up to date"))
1176 ------------------------
1177 checkModuleVersion old_mod_vers new_mod_vers
1178 | new_mod_vers == old_mod_vers
1179 = up_to_date (ptext SLIT("Module version unchanged"))
1182 = out_of_date_vers (ptext SLIT(" Module version has changed"))
1183 old_mod_vers new_mod_vers
1185 ------------------------
1186 checkExportList Nothing new_vers = upToDate
1187 checkExportList (Just v) new_vers = v /= new_vers
1189 ------------------------
1190 checkEntityUsage new_vers (name,old_vers)
1191 = case new_vers name of
1193 Nothing -> -- We used it before, but it ain't there now
1194 out_of_date (sep [ptext SLIT("No longer exported:"), ppr name])
1196 Just (_, new_vers) -- It's there, but is it up to date?
1197 | new_vers == old_vers -> traceHiDiffs (text " Up to date" <+> ppr name <+> parens (ppr new_vers)) `thenM_`
1199 | otherwise -> out_of_date_vers (ptext SLIT(" Out of date:") <+> ppr name)
1202 up_to_date msg = traceHiDiffs msg `thenM_` returnM upToDate
1203 out_of_date msg = traceHiDiffs msg `thenM_` returnM outOfDate
1204 out_of_date_vers msg old_vers new_vers
1205 = out_of_date (hsep [msg, ppr old_vers, ptext SLIT("->"), ppr new_vers])
1207 ----------------------
1208 checkList :: [IfG RecompileRequired] -> IfG RecompileRequired
1209 -- This helper is used in two places
1210 checkList [] = returnM upToDate
1211 checkList (check:checks) = check `thenM` \ recompile ->
1218 %************************************************************************
1220 Converting things to their Iface equivalents
1222 %************************************************************************
1225 tyThingToIfaceDecl :: TyThing -> IfaceDecl
1226 -- Assumption: the thing is already tidied, so that locally-bound names
1227 -- (lambdas, for-alls) already have non-clashing OccNames
1228 -- Reason: Iface stuff uses OccNames, and the conversion here does
1229 -- not do tidying on the way
1230 tyThingToIfaceDecl (AnId id)
1231 = IfaceId { ifName = getOccName id,
1232 ifType = toIfaceType (idType id),
1235 info = case toIfaceIdInfo (idInfo id) of
1237 items -> HasInfo items
1239 tyThingToIfaceDecl (AClass clas)
1240 = IfaceClass { ifCtxt = toIfaceContext sc_theta,
1241 ifName = getOccName clas,
1242 ifTyVars = toIfaceTvBndrs clas_tyvars,
1243 ifFDs = map toIfaceFD clas_fds,
1244 ifATs = map (tyThingToIfaceDecl . ATyCon) clas_ats,
1245 ifSigs = map toIfaceClassOp op_stuff,
1246 ifRec = boolToRecFlag (isRecursiveTyCon tycon) }
1248 (clas_tyvars, clas_fds, sc_theta, _, clas_ats, op_stuff)
1249 = classExtraBigSig clas
1250 tycon = classTyCon clas
1252 toIfaceClassOp (sel_id, def_meth)
1253 = ASSERT(sel_tyvars == clas_tyvars)
1254 IfaceClassOp (getOccName sel_id) def_meth (toIfaceType op_ty)
1256 -- Be careful when splitting the type, because of things
1257 -- like class Foo a where
1258 -- op :: (?x :: String) => a -> a
1259 -- and class Baz a where
1260 -- op :: (Ord a) => a -> a
1261 (sel_tyvars, rho_ty) = splitForAllTys (idType sel_id)
1262 op_ty = funResultTy rho_ty
1264 toIfaceFD (tvs1, tvs2) = (map getFS tvs1, map getFS tvs2)
1266 tyThingToIfaceDecl (ATyCon tycon)
1268 = IfaceSyn { ifName = getOccName tycon,
1269 ifTyVars = toIfaceTvBndrs tyvars,
1270 ifOpenSyn = syn_isOpen,
1271 ifSynRhs = toIfaceType syn_tyki,
1272 ifFamInst = famInstToIface (tyConFamInst_maybe tycon)
1276 = IfaceData { ifName = getOccName tycon,
1277 ifTyVars = toIfaceTvBndrs tyvars,
1278 ifCtxt = toIfaceContext (tyConStupidTheta tycon),
1279 ifCons = ifaceConDecls (algTyConRhs tycon),
1280 ifRec = boolToRecFlag (isRecursiveTyCon tycon),
1281 ifGadtSyntax = isGadtSyntaxTyCon tycon,
1282 ifGeneric = tyConHasGenerics tycon,
1283 ifFamInst = famInstToIface (tyConFamInst_maybe tycon)}
1285 | isForeignTyCon tycon
1286 = IfaceForeign { ifName = getOccName tycon,
1287 ifExtName = tyConExtName tycon }
1289 | otherwise = pprPanic "toIfaceDecl" (ppr tycon)
1291 tyvars = tyConTyVars tycon
1292 (syn_isOpen, syn_tyki) = case synTyConRhs tycon of
1293 OpenSynTyCon ki _ -> (True , ki)
1294 SynonymTyCon ty -> (False, ty)
1296 ifaceConDecls (NewTyCon { data_con = con }) =
1297 IfNewTyCon (ifaceConDecl con)
1298 ifaceConDecls (DataTyCon { data_cons = cons }) =
1299 IfDataTyCon (map ifaceConDecl cons)
1300 ifaceConDecls OpenTyCon {} = IfOpenDataTyCon
1301 ifaceConDecls AbstractTyCon = IfAbstractTyCon
1302 -- The last case happens when a TyCon has been trimmed during tidying
1303 -- Furthermore, tyThingToIfaceDecl is also used
1304 -- in TcRnDriver for GHCi, when browsing a module, in which case the
1305 -- AbstractTyCon case is perfectly sensible.
1307 ifaceConDecl data_con
1308 = IfCon { ifConOcc = getOccName (dataConName data_con),
1309 ifConInfix = dataConIsInfix data_con,
1310 ifConUnivTvs = toIfaceTvBndrs (dataConUnivTyVars data_con),
1311 ifConExTvs = toIfaceTvBndrs (dataConExTyVars data_con),
1312 ifConEqSpec = to_eq_spec (dataConEqSpec data_con),
1313 ifConCtxt = toIfaceContext (dataConEqTheta data_con ++ dataConDictTheta data_con),
1314 ifConArgTys = map toIfaceType (dataConOrigArgTys data_con),
1315 ifConFields = map getOccName
1316 (dataConFieldLabels data_con),
1317 ifConStricts = dataConStrictMarks data_con }
1319 to_eq_spec spec = [(getOccName tv, toIfaceType ty) | (tv,ty) <- spec]
1321 famInstToIface Nothing = Nothing
1322 famInstToIface (Just (famTyCon, instTys)) =
1323 Just (toIfaceTyCon famTyCon, map toIfaceType instTys)
1325 tyThingToIfaceDecl (ADataCon dc)
1326 = pprPanic "toIfaceDecl" (ppr dc) -- Should be trimmed out earlier
1329 getFS x = occNameFS (getOccName x)
1331 --------------------------
1332 instanceToIfaceInst :: Instance -> IfaceInst
1333 instanceToIfaceInst ispec@(Instance { is_dfun = dfun_id, is_flag = oflag,
1334 is_cls = cls_name, is_tcs = mb_tcs })
1335 = ASSERT( cls_name == className cls )
1336 IfaceInst { ifDFun = dfun_name,
1338 ifInstCls = cls_name,
1339 ifInstTys = map do_rough mb_tcs,
1342 do_rough Nothing = Nothing
1343 do_rough (Just n) = Just (toIfaceTyCon_name n)
1345 dfun_name = idName dfun_id
1346 mod = nameModule dfun_name
1347 is_local name = nameIsLocalOrFrom mod name
1349 -- Compute orphanhood. See Note [Orphans] in IfaceSyn
1350 (_, _, cls, tys) = tcSplitDFunTy (idType dfun_id)
1351 -- Slightly awkward: we need the Class to get the fundeps
1352 (tvs, fds) = classTvsFds cls
1353 arg_names = [filterNameSet is_local (tyClsNamesOfType ty) | ty <- tys]
1354 orph | is_local cls_name = Just (nameOccName cls_name)
1355 | all isJust mb_ns = head mb_ns
1356 | otherwise = Nothing
1358 mb_ns :: [Maybe OccName] -- One for each fundep; a locally-defined name
1359 -- that is not in the "determined" arguments
1360 mb_ns | null fds = [choose_one arg_names]
1361 | otherwise = map do_one fds
1362 do_one (ltvs,rtvs) = choose_one [ns | (tv,ns) <- tvs `zip` arg_names
1363 , not (tv `elem` rtvs)]
1365 choose_one :: [NameSet] -> Maybe OccName
1366 choose_one nss = case nameSetToList (unionManyNameSets nss) of
1368 (n:ns) -> Just (nameOccName n)
1370 --------------------------
1371 famInstToIfaceFamInst :: FamInst -> IfaceFamInst
1372 famInstToIfaceFamInst fi@(FamInst { fi_tycon = tycon,
1373 fi_fam = fam, fi_tcs = mb_tcs })
1374 = IfaceFamInst { ifFamInstTyCon = toIfaceTyCon tycon
1375 , ifFamInstFam = fam
1376 , ifFamInstTys = map do_rough mb_tcs }
1378 do_rough Nothing = Nothing
1379 do_rough (Just n) = Just (toIfaceTyCon_name n)
1381 --------------------------
1382 toIfaceLetBndr id = IfLetBndr (occNameFS (getOccName id))
1383 (toIfaceType (idType id))
1386 -- Stripped-down version of tcIfaceIdInfo
1387 -- Change this if you want to export more IdInfo for
1388 -- non-top-level Ids. Don't forget to change
1389 -- CoreTidy.tidyLetBndr too!
1391 -- See Note [IdInfo on nested let-bindings] in IfaceSyn
1393 inline_prag = inlinePragInfo id_info
1394 prag_info | isAlwaysActive inline_prag = NoInfo
1395 | otherwise = HasInfo [HsInline inline_prag]
1397 --------------------------
1398 toIfaceIdInfo :: IdInfo -> [IfaceInfoItem]
1399 toIfaceIdInfo id_info
1400 = catMaybes [arity_hsinfo, caf_hsinfo, strict_hsinfo,
1401 inline_hsinfo, wrkr_hsinfo, unfold_hsinfo]
1403 ------------ Arity --------------
1404 arity_info = arityInfo id_info
1405 arity_hsinfo | arity_info == 0 = Nothing
1406 | otherwise = Just (HsArity arity_info)
1408 ------------ Caf Info --------------
1409 caf_info = cafInfo id_info
1410 caf_hsinfo = case caf_info of
1411 NoCafRefs -> Just HsNoCafRefs
1414 ------------ Strictness --------------
1415 -- No point in explicitly exporting TopSig
1416 strict_hsinfo = case newStrictnessInfo id_info of
1417 Just sig | not (isTopSig sig) -> Just (HsStrictness sig)
1420 ------------ Worker --------------
1421 work_info = workerInfo id_info
1422 has_worker = workerExists work_info
1423 wrkr_hsinfo = case work_info of
1424 HasWorker work_id wrap_arity ->
1425 Just (HsWorker ((idName work_id)) wrap_arity)
1428 ------------ Unfolding --------------
1429 -- The unfolding is redundant if there is a worker
1430 unfold_info = unfoldingInfo id_info
1431 rhs = unfoldingTemplate unfold_info
1432 no_unfolding = neverUnfold unfold_info
1433 -- The CoreTidy phase retains unfolding info iff
1434 -- we want to expose the unfolding, taking into account
1435 -- unconditional NOINLINE, etc. See TidyPgm.addExternal
1436 unfold_hsinfo | no_unfolding = Nothing
1437 | has_worker = Nothing -- Unfolding is implicit
1438 | otherwise = Just (HsUnfold (toIfaceExpr rhs))
1440 ------------ Inline prag --------------
1441 inline_prag = inlinePragInfo id_info
1442 inline_hsinfo | isAlwaysActive inline_prag = Nothing
1443 | no_unfolding && not has_worker = Nothing
1444 -- If the iface file give no unfolding info, we
1445 -- don't need to say when inlining is OK!
1446 | otherwise = Just (HsInline inline_prag)
1448 --------------------------
1449 coreRuleToIfaceRule :: Module -> CoreRule -> IfaceRule
1450 coreRuleToIfaceRule mod (BuiltinRule { ru_fn = fn})
1451 = pprTrace "toHsRule: builtin" (ppr fn) $
1454 coreRuleToIfaceRule mod (Rule { ru_name = name, ru_fn = fn,
1455 ru_act = act, ru_bndrs = bndrs,
1456 ru_args = args, ru_rhs = rhs })
1457 = IfaceRule { ifRuleName = name, ifActivation = act,
1458 ifRuleBndrs = map toIfaceBndr bndrs,
1460 ifRuleArgs = map do_arg args,
1461 ifRuleRhs = toIfaceExpr rhs,
1464 -- For type args we must remove synonyms from the outermost
1465 -- level. Reason: so that when we read it back in we'll
1466 -- construct the same ru_rough field as we have right now;
1468 do_arg (Type ty) = IfaceType (toIfaceType (deNoteType ty))
1469 do_arg arg = toIfaceExpr arg
1471 -- Compute orphanhood. See Note [Orphans] in IfaceSyn
1472 -- A rule is an orphan only if none of the variables
1473 -- mentioned on its left-hand side are locally defined
1474 lhs_names = fn : nameSetToList (exprsFreeNames args)
1475 -- No need to delete bndrs, because
1476 -- exprsFreeNames finds only External names
1478 orph = case filter (nameIsLocalOrFrom mod) lhs_names of
1479 (n:ns) -> Just (nameOccName n)
1482 bogusIfaceRule :: Name -> IfaceRule
1483 bogusIfaceRule id_name
1484 = IfaceRule { ifRuleName = FSLIT("bogus"), ifActivation = NeverActive,
1485 ifRuleBndrs = [], ifRuleHead = id_name, ifRuleArgs = [],
1486 ifRuleRhs = IfaceExt id_name, ifRuleOrph = Nothing }
1488 ---------------------
1489 toIfaceExpr :: CoreExpr -> IfaceExpr
1490 toIfaceExpr (Var v) = toIfaceVar v
1491 toIfaceExpr (Lit l) = IfaceLit l
1492 toIfaceExpr (Type ty) = IfaceType (toIfaceType ty)
1493 toIfaceExpr (Lam x b) = IfaceLam (toIfaceBndr x) (toIfaceExpr b)
1494 toIfaceExpr (App f a) = toIfaceApp f [a]
1495 toIfaceExpr (Case s x ty as) = IfaceCase (toIfaceExpr s) (getFS x) (toIfaceType ty) (map toIfaceAlt as)
1496 toIfaceExpr (Let b e) = IfaceLet (toIfaceBind b) (toIfaceExpr e)
1497 toIfaceExpr (Cast e co) = IfaceCast (toIfaceExpr e) (toIfaceType co)
1498 toIfaceExpr (Note n e) = IfaceNote (toIfaceNote n) (toIfaceExpr e)
1500 ---------------------
1501 toIfaceNote (SCC cc) = IfaceSCC cc
1502 toIfaceNote InlineMe = IfaceInlineMe
1503 toIfaceNote (CoreNote s) = IfaceCoreNote s
1505 ---------------------
1506 toIfaceBind (NonRec b r) = IfaceNonRec (toIfaceLetBndr b) (toIfaceExpr r)
1507 toIfaceBind (Rec prs) = IfaceRec [(toIfaceLetBndr b, toIfaceExpr r) | (b,r) <- prs]
1509 ---------------------
1510 toIfaceAlt (c,bs,r) = (toIfaceCon c, map getFS bs, toIfaceExpr r)
1512 ---------------------
1513 toIfaceCon (DataAlt dc) | isTupleTyCon tc = IfaceTupleAlt (tupleTyConBoxity tc)
1514 | otherwise = IfaceDataAlt (getName dc)
1516 tc = dataConTyCon dc
1518 toIfaceCon (LitAlt l) = IfaceLitAlt l
1519 toIfaceCon DEFAULT = IfaceDefault
1521 ---------------------
1522 toIfaceApp (App f a) as = toIfaceApp f (a:as)
1523 toIfaceApp (Var v) as
1524 = case isDataConWorkId_maybe v of
1525 -- We convert the *worker* for tuples into IfaceTuples
1526 Just dc | isTupleTyCon tc && saturated
1527 -> IfaceTuple (tupleTyConBoxity tc) tup_args
1529 val_args = dropWhile isTypeArg as
1530 saturated = val_args `lengthIs` idArity v
1531 tup_args = map toIfaceExpr val_args
1532 tc = dataConTyCon dc
1534 other -> mkIfaceApps (toIfaceVar v) as
1536 toIfaceApp e as = mkIfaceApps (toIfaceExpr e) as
1538 mkIfaceApps f as = foldl (\f a -> IfaceApp f (toIfaceExpr a)) f as
1540 ---------------------
1541 toIfaceVar :: Id -> IfaceExpr
1543 | Just fcall <- isFCallId_maybe v = IfaceFCall fcall (toIfaceType (idType v))
1544 -- Foreign calls have special syntax
1545 | isExternalName name = IfaceExt name
1546 | Just (TickBox m ix) <- isTickBoxOp_maybe v
1548 | otherwise = IfaceLcl (getFS name)