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 -- bug #1617: on reload we weren't updating the PrintUnqualified
427 -- correctly. This stems from the fact that the interface had
428 -- not changed, so addVersionInfo returns the old ModIface
429 -- with the old GlobalRdrEnv (mi_globals).
430 ; let final_iface = new_iface{ mi_globals = Just rdr_env }
432 ; return (final_iface, no_change_at_all) }
434 r1 `le_rule` r2 = ifRuleName r1 <= ifRuleName r2
435 i1 `le_inst` i2 = ifDFun i1 `le_occ` ifDFun i2
436 i1 `le_fam_inst` i2 = ifFamInstTcName i1 `le_occ` ifFamInstTcName i2
438 le_occ :: Name -> Name -> Bool
439 -- Compare lexicographically by OccName, *not* by unique, because
440 -- the latter is not stable across compilations
441 le_occ n1 n2 = nameOccName n1 <= nameOccName n2
443 dflags = hsc_dflags hsc_env
444 deliberatelyOmitted x = panic ("Deliberately omitted: " ++ x)
445 ifFamInstTcName = ifaceTyConName . ifFamInstTyCon
447 flattenVectInfo (VectInfo { vectInfoVar = vVar
448 , vectInfoTyCon = vTyCon
451 ifaceVectInfoVar = [ Var.varName v
452 | (v, _) <- varEnvElts vVar],
453 ifaceVectInfoTyCon = [ tyConName t
454 | (t, t_v) <- nameEnvElts vTyCon
456 ifaceVectInfoTyConReuse = [ tyConName t
457 | (t, t_v) <- nameEnvElts vTyCon
461 -----------------------------
462 writeIfaceFile :: DynFlags -> ModLocation -> ModIface -> IO ()
463 writeIfaceFile dflags location new_iface
464 = do createDirectoryHierarchy (directoryOf hi_file_path)
465 writeBinIface dflags hi_file_path new_iface
466 where hi_file_path = ml_hi_file location
469 -- -----------------------------------------------------------------------------
470 -- Look up parents and versions of Names
472 -- This is like a global version of the mi_ver_fn field in each ModIface.
473 -- Given a Name, it finds the ModIface, and then uses mi_ver_fn to get
474 -- the parent and version info.
477 :: HscEnv -- needed to look up versions
478 -> ExternalPackageState -- ditto
479 -> (Name -> (OccName,Version))
480 mkParentVerFun hsc_env eps
483 mod = nameModule name
484 occ = nameOccName name
485 iface = lookupIfaceByModule (hsc_dflags hsc_env) hpt pit mod `orElse`
486 pprPanic "lookupVers2" (ppr mod <+> ppr occ)
488 mi_ver_fn iface occ `orElse`
489 pprPanic "lookupVers1" (ppr mod <+> ppr occ)
491 hpt = hsc_HPT hsc_env
494 -----------------------------------------------------------------------------
495 -- Compute version numbers for local decls
498 :: (Name -> (OccName,Version)) -- lookup parents and versions of names
499 -> Maybe ModIface -- The old interface, read from M.hi
500 -> ModIface -- The new interface (lacking decls)
501 -> [IfaceDecl] -- The new decls
502 -> (ModIface, -- Updated interface
503 Bool, -- True <=> no changes at all; no need to write Iface
505 Maybe SDoc) -- Warnings about orphans
507 addVersionInfo ver_fn Nothing new_iface new_decls
508 -- No old interface, so definitely write a new one!
509 = (new_iface { mi_orphan = not (null orph_insts && null orph_rules)
510 , mi_finsts = not . null $ mi_fam_insts new_iface
511 , mi_decls = [(initialVersion, decl) | decl <- new_decls]
512 , mi_ver_fn = mkIfaceVerCache (zip (repeat initialVersion)
516 ptext SLIT("No old interface file"),
517 pprOrphans orph_insts orph_rules)
519 orph_insts = filter (isNothing . ifInstOrph) (mi_insts new_iface)
520 orph_rules = filter (isNothing . ifRuleOrph) (mi_rules new_iface)
522 addVersionInfo ver_fn (Just old_iface@(ModIface {
523 mi_mod_vers = old_mod_vers,
524 mi_exp_vers = old_exp_vers,
525 mi_rule_vers = old_rule_vers,
526 mi_decls = old_decls,
527 mi_ver_fn = old_decl_vers,
528 mi_fix_fn = old_fixities }))
529 new_iface@(ModIface { mi_fix_fn = new_fixities })
532 = (old_iface, True, ptext SLIT("Interface file unchanged"), pp_orphs)
534 = (final_iface, False, vcat [ptext SLIT("Interface file has changed"),
535 nest 2 pp_diffs], pp_orphs)
537 final_iface = new_iface {
538 mi_mod_vers = bump_unless no_output_change old_mod_vers,
539 mi_exp_vers = bump_unless no_export_change old_exp_vers,
540 mi_rule_vers = bump_unless no_rule_change old_rule_vers,
541 mi_orphan = not (null new_orph_rules && null new_orph_insts),
542 mi_finsts = not . null $ mi_fam_insts new_iface,
543 mi_decls = decls_w_vers,
544 mi_ver_fn = mkIfaceVerCache decls_w_vers }
546 decls_w_vers = [(add_vers decl, decl) | decl <- new_decls]
549 (old_non_orph_insts, old_orph_insts) =
550 mkOrphMap ifInstOrph (mi_insts old_iface)
551 (new_non_orph_insts, new_orph_insts) =
552 mkOrphMap ifInstOrph (mi_insts new_iface)
553 old_fam_insts = mi_fam_insts old_iface
554 new_fam_insts = mi_fam_insts new_iface
555 same_insts occ = eqMaybeBy (eqListBy eqIfInst)
556 (lookupOccEnv old_non_orph_insts occ)
557 (lookupOccEnv new_non_orph_insts occ)
559 (old_non_orph_rules, old_orph_rules) =
560 mkOrphMap ifRuleOrph (mi_rules old_iface)
561 (new_non_orph_rules, new_orph_rules) =
562 mkOrphMap ifRuleOrph (mi_rules new_iface)
563 same_rules occ = eqMaybeBy (eqListBy eqIfRule)
564 (lookupOccEnv old_non_orph_rules occ)
565 (lookupOccEnv new_non_orph_rules occ)
567 -- Computing what changed
568 no_output_change = no_decl_change && no_rule_change &&
569 no_export_change && no_deprec_change
570 no_export_change = mi_exports new_iface == mi_exports old_iface
572 no_decl_change = isEmptyOccSet changed_occs
573 no_rule_change = not (changedWrtNames changed_occs (eqListBy eqIfRule old_orph_rules new_orph_rules)
574 || changedWrtNames changed_occs (eqListBy eqIfInst old_orph_insts new_orph_insts)
575 || changedWrtNames changed_occs (eqListBy eqIfFamInst old_fam_insts new_fam_insts))
576 no_deprec_change = mi_deprecs new_iface == mi_deprecs old_iface
578 -- If the usages havn't changed either, we don't need to write the interface file
579 no_other_changes = mi_usages new_iface == mi_usages old_iface &&
580 mi_deps new_iface == mi_deps old_iface &&
581 mi_hpc new_iface == mi_hpc old_iface
582 no_change_at_all = no_output_change && no_other_changes
584 pp_diffs = vcat [pp_change no_export_change "Export list"
585 (ppr old_exp_vers <+> arrow <+> ppr (mi_exp_vers final_iface)),
586 pp_change no_rule_change "Rules"
587 (ppr old_rule_vers <+> arrow <+> ppr (mi_rule_vers final_iface)),
588 pp_change no_deprec_change "Deprecations" empty,
589 pp_change no_other_changes "Usages" empty,
591 pp_change True what info = empty
592 pp_change False what info = text what <+> ptext SLIT("changed") <+> info
595 old_decl_env = mkOccEnv [(ifName decl, decl) | (_,decl) <- old_decls]
596 same_fixity n = bool (old_fixities n == new_fixities n)
599 -- Adding version info
600 new_version = bumpVersion old_mod_vers
601 -- Start from the old module version, not from
602 -- zero so that if you remove f, and then add
603 -- it again, you don't thereby reduce f's
606 add_vers decl | occ `elemOccSet` changed_occs = new_version
607 | otherwise = snd (expectJust "add_vers" (old_decl_vers occ))
608 -- If it's unchanged, there jolly well
609 where -- should be an old version number
613 -- Deciding which declarations have changed
615 -- For each local decl, the IfaceEq gives the list of things that
616 -- must be unchanged for the declaration as a whole to be unchanged.
617 eq_info :: [(OccName, IfaceEq)]
618 eq_info = map check_eq new_decls
620 | Just old_decl <- lookupOccEnv old_decl_env occ
621 = (occ, new_decl `eqIfDecl` old_decl &&& eq_indirects new_decl)
622 | otherwise {- No corresponding old decl -}
625 occ = ifName new_decl
627 eq_indirects :: IfaceDecl -> IfaceEq
628 -- When seeing if two decls are the same, remember to
629 -- check whether any relevant fixity or rules have changed
630 eq_indirects (IfaceId {ifName = occ}) = eq_ind_occ occ
631 eq_indirects (IfaceClass {ifName = cls_occ, ifSigs = sigs})
632 = same_insts cls_occ &&&
633 eq_ind_occs [op | IfaceClassOp op _ _ <- sigs]
634 eq_indirects (IfaceData {ifName = tc_occ, ifCons = cons})
635 = same_insts tc_occ &&& same_fixity tc_occ &&& -- The TyCon can have a fixity too
636 eq_ind_occs (map ifConOcc (visibleIfConDecls cons))
637 eq_indirects other = Equal -- Synonyms and foreign declarations
639 eq_ind_occ :: OccName -> IfaceEq -- For class ops and Ids; check fixity and rules
640 eq_ind_occ occ = same_fixity occ &&& same_rules occ
641 eq_ind_occs = foldr ((&&&) . eq_ind_occ) Equal
643 -- The Occs of declarations that changed.
644 changed_occs :: OccSet
645 changed_occs = computeChangedOccs ver_fn (mi_module new_iface)
646 (mi_usages old_iface) eq_info
650 pp_decl_diffs :: SDoc -- Nothing => no changes
652 | isEmptyOccSet changed_occs = empty
654 = vcat [ptext SLIT("Changed occs:") <+> ppr (occSetElts changed_occs),
655 ptext SLIT("Version change for these decls:"),
656 nest 2 (vcat (map show_change new_decls))]
658 eq_env = mkOccEnv eq_info
660 | not (occ `elemOccSet` changed_occs) = empty
662 = vcat [ppr occ <+> ppr (old_decl_vers occ) <+> arrow <+> ppr new_version,
665 occ = ifName new_decl
666 why = case lookupOccEnv eq_env occ of
667 Just (EqBut names) -> sep [ppr occ <> colon, ptext SLIT("Free vars (only) changed:") <> ppr names,
668 nest 2 (braces (fsep (map ppr (occSetElts
669 (occs `intersectOccSet` changed_occs)))))]
670 where occs = mkOccSet (map nameOccName (nameSetToList names))
672 | Just old_decl <- lookupOccEnv old_decl_env occ
673 -> vcat [ptext SLIT("Old:") <+> ppr old_decl,
674 ptext SLIT("New:") <+> ppr new_decl]
676 -> ppr occ <+> ptext SLIT("only in new interface")
677 other -> pprPanic "MkIface.show_change" (ppr occ)
679 pp_orphs = pprOrphans new_orph_insts new_orph_rules
682 pprOrphans insts rules
683 | null insts && null rules = Nothing
686 if null insts then empty else
687 hang (ptext SLIT("Warning: orphan instances:"))
688 2 (vcat (map ppr insts)),
689 if null rules then empty else
690 hang (ptext SLIT("Warning: orphan rules:"))
691 2 (vcat (map ppr rules))
695 :: (Name -> (OccName,Version)) -- get parents and versions
696 -> Module -- This module
697 -> [Usage] -- Usages from old iface
698 -> [(OccName, IfaceEq)] -- decl names, equality conditions
699 -> OccSet -- set of things that have changed
700 computeChangedOccs ver_fn this_module old_usages eq_info
701 = foldl add_changes emptyOccSet (stronglyConnComp edges)
704 -- return True if an external name has changed
705 name_changed :: Name -> Bool
707 | Just ents <- lookupUFM usg_modmap (moduleName mod)
708 = case lookupUFM ents parent_occ of
709 Nothing -> pprPanic "computeChangedOccs" (ppr nm)
710 Just v -> v < new_version
711 | otherwise = False -- must be in another package
714 (parent_occ, new_version) = ver_fn nm
716 -- Turn the usages from the old ModIface into a mapping
717 usg_modmap = listToUFM [ (usg_mod usg, listToUFM (usg_entities usg))
718 | usg <- old_usages ]
720 get_local_eq_info :: GenIfaceEq NameSet -> GenIfaceEq OccSet
721 get_local_eq_info Equal = Equal
722 get_local_eq_info NotEqual = NotEqual
723 get_local_eq_info (EqBut ns) = foldNameSet f Equal ns
724 where f name eq | nameModule name == this_module =
725 EqBut (unitOccSet (nameOccName name)) `and_occifeq` eq
726 | name_changed name = NotEqual
729 local_eq_infos = mapSnd get_local_eq_info eq_info
731 edges :: [((OccName, OccIfaceEq), Unique, [Unique])]
732 edges = [ (node, getUnique occ, map getUnique occs)
733 | node@(occ, iface_eq) <- local_eq_infos
734 , let occs = case iface_eq of
735 EqBut occ_set -> occSetElts occ_set
738 -- Changes in declarations
739 add_changes :: OccSet -> SCC (OccName, OccIfaceEq) -> OccSet
740 add_changes so_far (AcyclicSCC (occ, iface_eq))
741 | changedWrt so_far iface_eq -- This one has changed
742 = extendOccSet so_far occ
743 add_changes so_far (CyclicSCC pairs)
744 | changedWrt so_far (foldr1 and_occifeq iface_eqs)
745 -- One of this group has changed
746 = extendOccSetList so_far occs
747 where (occs, iface_eqs) = unzip pairs
748 add_changes so_far other = so_far
750 type OccIfaceEq = GenIfaceEq OccSet
752 changedWrt :: OccSet -> OccIfaceEq -> Bool
753 changedWrt so_far Equal = False
754 changedWrt so_far NotEqual = True
755 changedWrt so_far (EqBut kids) = so_far `intersectsOccSet` kids
757 changedWrtNames :: OccSet -> IfaceEq -> Bool
758 changedWrtNames so_far Equal = False
759 changedWrtNames so_far NotEqual = True
760 changedWrtNames so_far (EqBut kids) =
761 so_far `intersectsOccSet` mkOccSet (map nameOccName (nameSetToList kids))
763 and_occifeq :: OccIfaceEq -> OccIfaceEq -> OccIfaceEq
764 Equal `and_occifeq` x = x
765 NotEqual `and_occifeq` x = NotEqual
766 EqBut nms `and_occifeq` Equal = EqBut nms
767 EqBut nms `and_occifeq` NotEqual = NotEqual
768 EqBut nms1 `and_occifeq` EqBut nms2 = EqBut (nms1 `unionOccSets` nms2)
770 ----------------------
771 -- mkOrphMap partitions instance decls or rules into
772 -- (a) an OccEnv for ones that are not orphans,
773 -- mapping the local OccName to a list of its decls
774 -- (b) a list of orphan decls
775 mkOrphMap :: (decl -> Maybe OccName) -- (Just occ) for a non-orphan decl, keyed by occ
776 -- Nothing for an orphan decl
777 -> [decl] -- Sorted into canonical order
778 -> (OccEnv [decl], -- Non-orphan decls associated with their key;
779 -- each sublist in canonical order
780 [decl]) -- Orphan decls; in canonical order
781 mkOrphMap get_key decls
782 = foldl go (emptyOccEnv, []) decls
784 go (non_orphs, orphs) d
785 | Just occ <- get_key d
786 = (extendOccEnv_C (\ ds _ -> d:ds) non_orphs occ [d], orphs)
787 | otherwise = (non_orphs, d:orphs)
789 ----------------------
790 bump_unless :: Bool -> Version -> Version
791 bump_unless True v = v -- True <=> no change
792 bump_unless False v = bumpVersion v
796 %*********************************************************
798 \subsection{Keeping track of what we've slurped, and version numbers}
800 %*********************************************************
804 mkUsageInfo :: HscEnv
805 -> ModuleEnv (Module, [(ModuleName, Bool, SrcSpan)])
806 -> [(ModuleName, IsBootInterface)]
807 -> NameSet -> IO [Usage]
808 mkUsageInfo hsc_env dir_imp_mods dep_mods used_names
809 = do { eps <- hscEPS hsc_env
810 ; let usages = mk_usage_info (eps_PIT eps) hsc_env
811 dir_imp_mods dep_mods used_names
812 ; usages `seqList` return usages }
813 -- seq the list of Usages returned: occasionally these
814 -- don't get evaluated for a while and we can end up hanging on to
815 -- the entire collection of Ifaces.
817 mk_usage_info :: PackageIfaceTable
819 -> ModuleEnv (Module, [(ModuleName, Bool, SrcSpan)])
820 -> [(ModuleName, IsBootInterface)]
823 mk_usage_info pit hsc_env dir_imp_mods dep_mods used_names
824 = mapCatMaybes mkUsage dep_mods
825 -- ToDo: do we need to sort into canonical order?
827 hpt = hsc_HPT hsc_env
828 dflags = hsc_dflags hsc_env
830 -- ent_map groups together all the things imported and used
831 -- from a particular module in this package
832 ent_map :: ModuleEnv [OccName]
833 ent_map = foldNameSet add_mv emptyModuleEnv used_names
835 | isWiredInName name = mv_map -- ignore wired-in names
837 = case nameModule_maybe name of
838 Nothing -> mv_map -- ignore internal names
839 Just mod -> extendModuleEnv_C add_item mv_map mod [occ]
841 occ = nameOccName name
842 add_item occs _ = occ:occs
844 depend_on_exports mod = case lookupModuleEnv dir_imp_mods mod of
845 Just (_, xs) -> any (\(_, no_imp, _) -> not no_imp) xs
848 -- We want to create a Usage for a home module if
849 -- a) we used something from; has something in used_names
850 -- b) we imported all of it, even if we used nothing from it
851 -- (need to recompile if its export list changes: export_vers)
852 -- c) is a home-package orphan or family-instance module (need to
853 -- recompile if its instance decls change: rules_vers)
854 mkUsage :: (ModuleName, IsBootInterface) -> Maybe Usage
855 mkUsage (mod_name, _)
856 | isNothing maybe_iface -- We can't depend on it if we didn't
857 || (null used_occs -- load its interface.
858 && isNothing export_vers
861 = Nothing -- Record no usage info
864 = Just (Usage { usg_name = mod_name,
866 usg_exports = export_vers,
867 usg_entities = fmToList ent_vers,
868 usg_rules = rules_vers })
870 maybe_iface = lookupIfaceByModule dflags hpt pit mod
871 -- In one-shot mode, the interfaces for home-package
872 -- modules accumulate in the PIT not HPT. Sigh.
874 mod = mkModule (thisPackage dflags) mod_name
876 Just iface = maybe_iface
877 orphan_mod = mi_orphan iface
878 finsts_mod = mi_finsts iface
879 version_env = mi_ver_fn iface
880 mod_vers = mi_mod_vers iface
881 rules_vers = mi_rule_vers iface
882 export_vers | depend_on_exports mod = Just (mi_exp_vers iface)
883 | otherwise = Nothing
885 used_occs = lookupModuleEnv ent_map mod `orElse` []
887 -- Making a FiniteMap here ensures that (a) we remove duplicates
888 -- when we have usages on several subordinates of a single parent,
889 -- and (b) that the usages emerge in a canonical order, which
890 -- is why we use FiniteMap rather than OccEnv: FiniteMap works
891 -- using Ord on the OccNames, which is a lexicographic ordering.
892 ent_vers :: FiniteMap OccName Version
893 ent_vers = listToFM (map lookup_occ used_occs)
896 case version_env occ of
897 Nothing -> pprTrace "hmm, strange" (ppr mod <+> ppr occ) $
898 (occ, initialVersion) -- does this ever happen?
899 Just (parent, version) -> (parent, version)
903 mkIfaceExports :: [AvailInfo]
904 -> [(Module, [GenAvailInfo OccName])]
905 -- Group by module and sort by occurrence
906 -- This keeps the list in canonical order
907 mkIfaceExports exports
908 = [ (mod, eltsFM avails)
909 | (mod, avails) <- fmToList groupFM
912 -- Group by the module where the exported entities are defined
913 -- (which may not be the same for all Names in an Avail)
914 -- Deliberately use FiniteMap rather than UniqFM so we
915 -- get a canonical ordering
916 groupFM :: ModuleEnv (FiniteMap FastString (GenAvailInfo OccName))
917 groupFM = foldl add emptyModuleEnv exports
919 add_one :: ModuleEnv (FiniteMap FastString (GenAvailInfo OccName))
920 -> Module -> GenAvailInfo OccName
921 -> ModuleEnv (FiniteMap FastString (GenAvailInfo OccName))
922 add_one env mod avail
923 = extendModuleEnv_C plusFM env mod
924 (unitFM (occNameFS (availName avail)) avail)
926 -- NB: we should not get T(X) and T(Y) in the export list
927 -- else the plusFM will simply discard one! They
928 -- should have been combined by now.
930 = add_one env (nameModule n) (Avail (nameOccName n))
932 add env (AvailTC tc ns)
933 = foldl add_for_mod env mods
935 tc_occ = nameOccName tc
936 mods = nub (map nameModule ns)
937 -- Usually just one, but see Note [Original module]
940 = add_one env mod (AvailTC tc_occ (sort names_from_mod))
941 -- NB. sort the children, we need a canonical order
943 names_from_mod = [nameOccName n | n <- ns, nameModule n == mod]
946 Note [Orignal module]
947 ~~~~~~~~~~~~~~~~~~~~~
949 module X where { data family T }
950 module Y( T(..) ) where { import X; data instance T Int = MkT Int }
951 The exported Avail from Y will look like
954 - only MkT is brought into scope by the data instance;
955 - but the parent (used for grouping and naming in T(..) exports) is X.T
956 - and in this case we export X.T too
958 In the result of MkIfaceExports, the names are grouped by defining module,
959 so we may need to split up a single Avail into multiple ones.
962 %************************************************************************
964 Load the old interface file for this module (unless
965 we have it aleady), and check whether it is up to date
968 %************************************************************************
971 checkOldIface :: HscEnv
973 -> Bool -- Source unchanged
974 -> Maybe ModIface -- Old interface from compilation manager, if any
975 -> IO (RecompileRequired, Maybe ModIface)
977 checkOldIface hsc_env mod_summary source_unchanged maybe_iface
978 = do { showPass (hsc_dflags hsc_env)
979 ("Checking old interface for " ++
980 showSDoc (ppr (ms_mod mod_summary))) ;
982 ; initIfaceCheck hsc_env $
983 check_old_iface hsc_env mod_summary source_unchanged maybe_iface
986 check_old_iface hsc_env mod_summary source_unchanged maybe_iface
987 = do -- CHECK WHETHER THE SOURCE HAS CHANGED
988 { ifM (not source_unchanged)
989 (traceHiDiffs (nest 4 (text "Source file changed or recompilation check turned off")))
991 -- If the source has changed and we're in interactive mode, avoid reading
992 -- an interface; just return the one we might have been supplied with.
993 ; let dflags = hsc_dflags hsc_env
994 ; if not (isObjectTarget (hscTarget dflags)) && not source_unchanged then
995 return (outOfDate, maybe_iface)
997 case maybe_iface of {
998 Just old_iface -> do -- Use the one we already have
999 { traceIf (text "We already have the old interface for" <+> ppr (ms_mod mod_summary))
1000 ; recomp <- checkVersions hsc_env source_unchanged mod_summary old_iface
1001 ; return (recomp, Just old_iface) }
1005 -- Try and read the old interface for the current module
1006 -- from the .hi file left from the last time we compiled it
1007 { let iface_path = msHiFilePath mod_summary
1008 ; read_result <- readIface (ms_mod mod_summary) iface_path False
1009 ; case read_result of {
1010 Failed err -> do -- Old interface file not found, or garbled; give up
1011 { traceIf (text "FYI: cannot read old interface file:"
1013 ; return (outOfDate, Nothing) }
1015 ; Succeeded iface -> do
1017 -- We have got the old iface; check its versions
1018 { traceIf (text "Read the interface file" <+> text iface_path)
1019 ; recomp <- checkVersions hsc_env source_unchanged mod_summary iface
1020 ; returnM (recomp, Just iface)
1025 @recompileRequired@ is called from the HscMain. It checks whether
1026 a recompilation is required. It needs access to the persistent state,
1027 finder, etc, because it may have to load lots of interface files to
1028 check their versions.
1031 type RecompileRequired = Bool
1032 upToDate = False -- Recompile not required
1033 outOfDate = True -- Recompile required
1035 checkVersions :: HscEnv
1036 -> Bool -- True <=> source unchanged
1038 -> ModIface -- Old interface
1039 -> IfG RecompileRequired
1040 checkVersions hsc_env source_unchanged mod_summary iface
1041 | not source_unchanged
1044 = do { traceHiDiffs (text "Considering whether compilation is required for" <+>
1045 ppr (mi_module iface) <> colon)
1047 ; recomp <- checkDependencies hsc_env mod_summary iface
1048 ; if recomp then return outOfDate else do {
1050 -- Source code unchanged and no errors yet... carry on
1052 -- First put the dependent-module info, read from the old interface, into the envt,
1053 -- so that when we look for interfaces we look for the right one (.hi or .hi-boot)
1055 -- It's just temporary because either the usage check will succeed
1056 -- (in which case we are done with this module) or it'll fail (in which
1057 -- case we'll compile the module from scratch anyhow).
1059 -- We do this regardless of compilation mode, although in --make mode
1060 -- all the dependent modules should be in the HPT already, so it's
1062 updateEps_ $ \eps -> eps { eps_is_boot = mod_deps }
1064 ; let this_pkg = thisPackage (hsc_dflags hsc_env)
1065 ; checkList [checkModUsage this_pkg u | u <- mi_usages iface]
1068 -- This is a bit of a hack really
1069 mod_deps :: ModuleNameEnv (ModuleName, IsBootInterface)
1070 mod_deps = mkModDeps (dep_mods (mi_deps iface))
1073 -- If the direct imports of this module are resolved to targets that
1074 -- are not among the dependencies of the previous interface file,
1075 -- then we definitely need to recompile. This catches cases like
1076 -- - an exposed package has been upgraded
1077 -- - we are compiling with different package flags
1078 -- - a home module that was shadowing a package module has been removed
1079 -- - a new home module has been added that shadows a package module
1082 -- Returns True if recompilation is required.
1083 checkDependencies :: HscEnv -> ModSummary -> ModIface -> IfG RecompileRequired
1084 checkDependencies hsc_env summary iface
1085 = orM (map dep_missing (ms_imps summary ++ ms_srcimps summary))
1087 prev_dep_mods = dep_mods (mi_deps iface)
1088 prev_dep_pkgs = dep_pkgs (mi_deps iface)
1090 this_pkg = thisPackage (hsc_dflags hsc_env)
1092 orM = foldr f (return False)
1093 where f m rest = do b <- m; if b then return True else rest
1095 dep_missing (L _ mod) = do
1096 find_res <- ioToIOEnv $ findImportedModule hsc_env mod Nothing
1100 -> if moduleName mod `notElem` map fst prev_dep_mods
1101 then do traceHiDiffs $
1102 text "imported module " <> quotes (ppr mod) <>
1103 text " not among previous dependencies"
1108 -> if pkg `notElem` prev_dep_pkgs
1109 then do traceHiDiffs $
1110 text "imported module " <> quotes (ppr mod) <>
1111 text " is from package " <> quotes (ppr pkg) <>
1112 text ", which is not among previous dependencies"
1116 where pkg = modulePackageId mod
1117 _otherwise -> return outOfDate
1119 checkModUsage :: PackageId ->Usage -> IfG RecompileRequired
1120 -- Given the usage information extracted from the old
1121 -- M.hi file for the module being compiled, figure out
1122 -- whether M needs to be recompiled.
1124 checkModUsage this_pkg (Usage { usg_name = mod_name, usg_mod = old_mod_vers,
1125 usg_rules = old_rule_vers,
1126 usg_exports = maybe_old_export_vers,
1127 usg_entities = old_decl_vers })
1128 = -- Load the imported interface is possible
1130 doc_str = sep [ptext SLIT("need version info for"), ppr mod_name]
1132 traceHiDiffs (text "Checking usages for module" <+> ppr mod_name) `thenM_`
1135 mod = mkModule this_pkg mod_name
1137 loadInterface doc_str mod ImportBySystem `thenM` \ mb_iface ->
1138 -- Load the interface, but don't complain on failure;
1139 -- Instead, get an Either back which we can test
1142 Failed exn -> (out_of_date (sep [ptext SLIT("Can't find version number for module"),
1144 -- Couldn't find or parse a module mentioned in the
1145 -- old interface file. Don't complain -- it might just be that
1146 -- the current module doesn't need that import and it's been deleted
1150 new_mod_vers = mi_mod_vers iface
1151 new_decl_vers = mi_ver_fn iface
1152 new_export_vers = mi_exp_vers iface
1153 new_rule_vers = mi_rule_vers iface
1156 checkModuleVersion old_mod_vers new_mod_vers `thenM` \ recompile ->
1157 if not recompile then
1161 -- CHECK EXPORT LIST
1162 if checkExportList maybe_old_export_vers new_export_vers then
1163 out_of_date_vers (ptext SLIT(" Export list changed"))
1164 (expectJust "checkModUsage" maybe_old_export_vers)
1169 if old_rule_vers /= new_rule_vers then
1170 out_of_date_vers (ptext SLIT(" Rules changed"))
1171 old_rule_vers new_rule_vers
1174 -- CHECK ITEMS ONE BY ONE
1175 checkList [checkEntityUsage new_decl_vers u | u <- old_decl_vers] `thenM` \ recompile ->
1177 returnM outOfDate -- This one failed, so just bail out now
1179 up_to_date (ptext SLIT(" Great! The bits I use are up to date"))
1182 ------------------------
1183 checkModuleVersion old_mod_vers new_mod_vers
1184 | new_mod_vers == old_mod_vers
1185 = up_to_date (ptext SLIT("Module version unchanged"))
1188 = out_of_date_vers (ptext SLIT(" Module version has changed"))
1189 old_mod_vers new_mod_vers
1191 ------------------------
1192 checkExportList Nothing new_vers = upToDate
1193 checkExportList (Just v) new_vers = v /= new_vers
1195 ------------------------
1196 checkEntityUsage new_vers (name,old_vers)
1197 = case new_vers name of
1199 Nothing -> -- We used it before, but it ain't there now
1200 out_of_date (sep [ptext SLIT("No longer exported:"), ppr name])
1202 Just (_, new_vers) -- It's there, but is it up to date?
1203 | new_vers == old_vers -> traceHiDiffs (text " Up to date" <+> ppr name <+> parens (ppr new_vers)) `thenM_`
1205 | otherwise -> out_of_date_vers (ptext SLIT(" Out of date:") <+> ppr name)
1208 up_to_date msg = traceHiDiffs msg `thenM_` returnM upToDate
1209 out_of_date msg = traceHiDiffs msg `thenM_` returnM outOfDate
1210 out_of_date_vers msg old_vers new_vers
1211 = out_of_date (hsep [msg, ppr old_vers, ptext SLIT("->"), ppr new_vers])
1213 ----------------------
1214 checkList :: [IfG RecompileRequired] -> IfG RecompileRequired
1215 -- This helper is used in two places
1216 checkList [] = returnM upToDate
1217 checkList (check:checks) = check `thenM` \ recompile ->
1224 %************************************************************************
1226 Converting things to their Iface equivalents
1228 %************************************************************************
1231 tyThingToIfaceDecl :: TyThing -> IfaceDecl
1232 -- Assumption: the thing is already tidied, so that locally-bound names
1233 -- (lambdas, for-alls) already have non-clashing OccNames
1234 -- Reason: Iface stuff uses OccNames, and the conversion here does
1235 -- not do tidying on the way
1236 tyThingToIfaceDecl (AnId id)
1237 = IfaceId { ifName = getOccName id,
1238 ifType = toIfaceType (idType id),
1241 info = case toIfaceIdInfo (idInfo id) of
1243 items -> HasInfo items
1245 tyThingToIfaceDecl (AClass clas)
1246 = IfaceClass { ifCtxt = toIfaceContext sc_theta,
1247 ifName = getOccName clas,
1248 ifTyVars = toIfaceTvBndrs clas_tyvars,
1249 ifFDs = map toIfaceFD clas_fds,
1250 ifATs = map (tyThingToIfaceDecl . ATyCon) clas_ats,
1251 ifSigs = map toIfaceClassOp op_stuff,
1252 ifRec = boolToRecFlag (isRecursiveTyCon tycon) }
1254 (clas_tyvars, clas_fds, sc_theta, _, clas_ats, op_stuff)
1255 = classExtraBigSig clas
1256 tycon = classTyCon clas
1258 toIfaceClassOp (sel_id, def_meth)
1259 = ASSERT(sel_tyvars == clas_tyvars)
1260 IfaceClassOp (getOccName sel_id) def_meth (toIfaceType op_ty)
1262 -- Be careful when splitting the type, because of things
1263 -- like class Foo a where
1264 -- op :: (?x :: String) => a -> a
1265 -- and class Baz a where
1266 -- op :: (Ord a) => a -> a
1267 (sel_tyvars, rho_ty) = splitForAllTys (idType sel_id)
1268 op_ty = funResultTy rho_ty
1270 toIfaceFD (tvs1, tvs2) = (map getFS tvs1, map getFS tvs2)
1272 tyThingToIfaceDecl (ATyCon tycon)
1274 = IfaceSyn { ifName = getOccName tycon,
1275 ifTyVars = toIfaceTvBndrs tyvars,
1276 ifOpenSyn = syn_isOpen,
1277 ifSynRhs = toIfaceType syn_tyki,
1278 ifFamInst = famInstToIface (tyConFamInst_maybe tycon)
1282 = IfaceData { ifName = getOccName tycon,
1283 ifTyVars = toIfaceTvBndrs tyvars,
1284 ifCtxt = toIfaceContext (tyConStupidTheta tycon),
1285 ifCons = ifaceConDecls (algTyConRhs tycon),
1286 ifRec = boolToRecFlag (isRecursiveTyCon tycon),
1287 ifGadtSyntax = isGadtSyntaxTyCon tycon,
1288 ifGeneric = tyConHasGenerics tycon,
1289 ifFamInst = famInstToIface (tyConFamInst_maybe tycon)}
1291 | isForeignTyCon tycon
1292 = IfaceForeign { ifName = getOccName tycon,
1293 ifExtName = tyConExtName tycon }
1295 | otherwise = pprPanic "toIfaceDecl" (ppr tycon)
1297 tyvars = tyConTyVars tycon
1298 (syn_isOpen, syn_tyki) = case synTyConRhs tycon of
1299 OpenSynTyCon ki _ -> (True , ki)
1300 SynonymTyCon ty -> (False, ty)
1302 ifaceConDecls (NewTyCon { data_con = con }) =
1303 IfNewTyCon (ifaceConDecl con)
1304 ifaceConDecls (DataTyCon { data_cons = cons }) =
1305 IfDataTyCon (map ifaceConDecl cons)
1306 ifaceConDecls OpenTyCon {} = IfOpenDataTyCon
1307 ifaceConDecls AbstractTyCon = IfAbstractTyCon
1308 -- The last case happens when a TyCon has been trimmed during tidying
1309 -- Furthermore, tyThingToIfaceDecl is also used
1310 -- in TcRnDriver for GHCi, when browsing a module, in which case the
1311 -- AbstractTyCon case is perfectly sensible.
1313 ifaceConDecl data_con
1314 = IfCon { ifConOcc = getOccName (dataConName data_con),
1315 ifConInfix = dataConIsInfix data_con,
1316 ifConUnivTvs = toIfaceTvBndrs (dataConUnivTyVars data_con),
1317 ifConExTvs = toIfaceTvBndrs (dataConExTyVars data_con),
1318 ifConEqSpec = to_eq_spec (dataConEqSpec data_con),
1319 ifConCtxt = toIfaceContext (dataConEqTheta data_con ++ dataConDictTheta data_con),
1320 ifConArgTys = map toIfaceType (dataConOrigArgTys data_con),
1321 ifConFields = map getOccName
1322 (dataConFieldLabels data_con),
1323 ifConStricts = dataConStrictMarks data_con }
1325 to_eq_spec spec = [(getOccName tv, toIfaceType ty) | (tv,ty) <- spec]
1327 famInstToIface Nothing = Nothing
1328 famInstToIface (Just (famTyCon, instTys)) =
1329 Just (toIfaceTyCon famTyCon, map toIfaceType instTys)
1331 tyThingToIfaceDecl (ADataCon dc)
1332 = pprPanic "toIfaceDecl" (ppr dc) -- Should be trimmed out earlier
1335 getFS x = occNameFS (getOccName x)
1337 --------------------------
1338 instanceToIfaceInst :: Instance -> IfaceInst
1339 instanceToIfaceInst ispec@(Instance { is_dfun = dfun_id, is_flag = oflag,
1340 is_cls = cls_name, is_tcs = mb_tcs })
1341 = ASSERT( cls_name == className cls )
1342 IfaceInst { ifDFun = dfun_name,
1344 ifInstCls = cls_name,
1345 ifInstTys = map do_rough mb_tcs,
1348 do_rough Nothing = Nothing
1349 do_rough (Just n) = Just (toIfaceTyCon_name n)
1351 dfun_name = idName dfun_id
1352 mod = nameModule dfun_name
1353 is_local name = nameIsLocalOrFrom mod name
1355 -- Compute orphanhood. See Note [Orphans] in IfaceSyn
1356 (_, _, cls, tys) = tcSplitDFunTy (idType dfun_id)
1357 -- Slightly awkward: we need the Class to get the fundeps
1358 (tvs, fds) = classTvsFds cls
1359 arg_names = [filterNameSet is_local (tyClsNamesOfType ty) | ty <- tys]
1360 orph | is_local cls_name = Just (nameOccName cls_name)
1361 | all isJust mb_ns = head mb_ns
1362 | otherwise = Nothing
1364 mb_ns :: [Maybe OccName] -- One for each fundep; a locally-defined name
1365 -- that is not in the "determined" arguments
1366 mb_ns | null fds = [choose_one arg_names]
1367 | otherwise = map do_one fds
1368 do_one (ltvs,rtvs) = choose_one [ns | (tv,ns) <- tvs `zip` arg_names
1369 , not (tv `elem` rtvs)]
1371 choose_one :: [NameSet] -> Maybe OccName
1372 choose_one nss = case nameSetToList (unionManyNameSets nss) of
1374 (n:ns) -> Just (nameOccName n)
1376 --------------------------
1377 famInstToIfaceFamInst :: FamInst -> IfaceFamInst
1378 famInstToIfaceFamInst fi@(FamInst { fi_tycon = tycon,
1379 fi_fam = fam, fi_tcs = mb_tcs })
1380 = IfaceFamInst { ifFamInstTyCon = toIfaceTyCon tycon
1381 , ifFamInstFam = fam
1382 , ifFamInstTys = map do_rough mb_tcs }
1384 do_rough Nothing = Nothing
1385 do_rough (Just n) = Just (toIfaceTyCon_name n)
1387 --------------------------
1388 toIfaceLetBndr id = IfLetBndr (occNameFS (getOccName id))
1389 (toIfaceType (idType id))
1392 -- Stripped-down version of tcIfaceIdInfo
1393 -- Change this if you want to export more IdInfo for
1394 -- non-top-level Ids. Don't forget to change
1395 -- CoreTidy.tidyLetBndr too!
1397 -- See Note [IdInfo on nested let-bindings] in IfaceSyn
1399 inline_prag = inlinePragInfo id_info
1400 prag_info | isAlwaysActive inline_prag = NoInfo
1401 | otherwise = HasInfo [HsInline inline_prag]
1403 --------------------------
1404 toIfaceIdInfo :: IdInfo -> [IfaceInfoItem]
1405 toIfaceIdInfo id_info
1406 = catMaybes [arity_hsinfo, caf_hsinfo, strict_hsinfo,
1407 inline_hsinfo, wrkr_hsinfo, unfold_hsinfo]
1409 ------------ Arity --------------
1410 arity_info = arityInfo id_info
1411 arity_hsinfo | arity_info == 0 = Nothing
1412 | otherwise = Just (HsArity arity_info)
1414 ------------ Caf Info --------------
1415 caf_info = cafInfo id_info
1416 caf_hsinfo = case caf_info of
1417 NoCafRefs -> Just HsNoCafRefs
1420 ------------ Strictness --------------
1421 -- No point in explicitly exporting TopSig
1422 strict_hsinfo = case newStrictnessInfo id_info of
1423 Just sig | not (isTopSig sig) -> Just (HsStrictness sig)
1426 ------------ Worker --------------
1427 work_info = workerInfo id_info
1428 has_worker = workerExists work_info
1429 wrkr_hsinfo = case work_info of
1430 HasWorker work_id wrap_arity ->
1431 Just (HsWorker ((idName work_id)) wrap_arity)
1434 ------------ Unfolding --------------
1435 -- The unfolding is redundant if there is a worker
1436 unfold_info = unfoldingInfo id_info
1437 rhs = unfoldingTemplate unfold_info
1438 no_unfolding = neverUnfold unfold_info
1439 -- The CoreTidy phase retains unfolding info iff
1440 -- we want to expose the unfolding, taking into account
1441 -- unconditional NOINLINE, etc. See TidyPgm.addExternal
1442 unfold_hsinfo | no_unfolding = Nothing
1443 | has_worker = Nothing -- Unfolding is implicit
1444 | otherwise = Just (HsUnfold (toIfaceExpr rhs))
1446 ------------ Inline prag --------------
1447 inline_prag = inlinePragInfo id_info
1448 inline_hsinfo | isAlwaysActive inline_prag = Nothing
1449 | no_unfolding && not has_worker = Nothing
1450 -- If the iface file give no unfolding info, we
1451 -- don't need to say when inlining is OK!
1452 | otherwise = Just (HsInline inline_prag)
1454 --------------------------
1455 coreRuleToIfaceRule :: Module -> CoreRule -> IfaceRule
1456 coreRuleToIfaceRule mod (BuiltinRule { ru_fn = fn})
1457 = pprTrace "toHsRule: builtin" (ppr fn) $
1460 coreRuleToIfaceRule mod (Rule { ru_name = name, ru_fn = fn,
1461 ru_act = act, ru_bndrs = bndrs,
1462 ru_args = args, ru_rhs = rhs })
1463 = IfaceRule { ifRuleName = name, ifActivation = act,
1464 ifRuleBndrs = map toIfaceBndr bndrs,
1466 ifRuleArgs = map do_arg args,
1467 ifRuleRhs = toIfaceExpr rhs,
1470 -- For type args we must remove synonyms from the outermost
1471 -- level. Reason: so that when we read it back in we'll
1472 -- construct the same ru_rough field as we have right now;
1474 do_arg (Type ty) = IfaceType (toIfaceType (deNoteType ty))
1475 do_arg arg = toIfaceExpr arg
1477 -- Compute orphanhood. See Note [Orphans] in IfaceSyn
1478 -- A rule is an orphan only if none of the variables
1479 -- mentioned on its left-hand side are locally defined
1480 lhs_names = fn : nameSetToList (exprsFreeNames args)
1481 -- No need to delete bndrs, because
1482 -- exprsFreeNames finds only External names
1484 orph = case filter (nameIsLocalOrFrom mod) lhs_names of
1485 (n:ns) -> Just (nameOccName n)
1488 bogusIfaceRule :: Name -> IfaceRule
1489 bogusIfaceRule id_name
1490 = IfaceRule { ifRuleName = FSLIT("bogus"), ifActivation = NeverActive,
1491 ifRuleBndrs = [], ifRuleHead = id_name, ifRuleArgs = [],
1492 ifRuleRhs = IfaceExt id_name, ifRuleOrph = Nothing }
1494 ---------------------
1495 toIfaceExpr :: CoreExpr -> IfaceExpr
1496 toIfaceExpr (Var v) = toIfaceVar v
1497 toIfaceExpr (Lit l) = IfaceLit l
1498 toIfaceExpr (Type ty) = IfaceType (toIfaceType ty)
1499 toIfaceExpr (Lam x b) = IfaceLam (toIfaceBndr x) (toIfaceExpr b)
1500 toIfaceExpr (App f a) = toIfaceApp f [a]
1501 toIfaceExpr (Case s x ty as) = IfaceCase (toIfaceExpr s) (getFS x) (toIfaceType ty) (map toIfaceAlt as)
1502 toIfaceExpr (Let b e) = IfaceLet (toIfaceBind b) (toIfaceExpr e)
1503 toIfaceExpr (Cast e co) = IfaceCast (toIfaceExpr e) (toIfaceType co)
1504 toIfaceExpr (Note n e) = IfaceNote (toIfaceNote n) (toIfaceExpr e)
1506 ---------------------
1507 toIfaceNote (SCC cc) = IfaceSCC cc
1508 toIfaceNote InlineMe = IfaceInlineMe
1509 toIfaceNote (CoreNote s) = IfaceCoreNote s
1511 ---------------------
1512 toIfaceBind (NonRec b r) = IfaceNonRec (toIfaceLetBndr b) (toIfaceExpr r)
1513 toIfaceBind (Rec prs) = IfaceRec [(toIfaceLetBndr b, toIfaceExpr r) | (b,r) <- prs]
1515 ---------------------
1516 toIfaceAlt (c,bs,r) = (toIfaceCon c, map getFS bs, toIfaceExpr r)
1518 ---------------------
1519 toIfaceCon (DataAlt dc) | isTupleTyCon tc = IfaceTupleAlt (tupleTyConBoxity tc)
1520 | otherwise = IfaceDataAlt (getName dc)
1522 tc = dataConTyCon dc
1524 toIfaceCon (LitAlt l) = IfaceLitAlt l
1525 toIfaceCon DEFAULT = IfaceDefault
1527 ---------------------
1528 toIfaceApp (App f a) as = toIfaceApp f (a:as)
1529 toIfaceApp (Var v) as
1530 = case isDataConWorkId_maybe v of
1531 -- We convert the *worker* for tuples into IfaceTuples
1532 Just dc | isTupleTyCon tc && saturated
1533 -> IfaceTuple (tupleTyConBoxity tc) tup_args
1535 val_args = dropWhile isTypeArg as
1536 saturated = val_args `lengthIs` idArity v
1537 tup_args = map toIfaceExpr val_args
1538 tc = dataConTyCon dc
1540 other -> mkIfaceApps (toIfaceVar v) as
1542 toIfaceApp e as = mkIfaceApps (toIfaceExpr e) as
1544 mkIfaceApps f as = foldl (\f a -> IfaceApp f (toIfaceExpr a)) f as
1546 ---------------------
1547 toIfaceVar :: Id -> IfaceExpr
1549 | Just fcall <- isFCallId_maybe v = IfaceFCall fcall (toIfaceType (idType v))
1550 -- Foreign calls have special syntax
1551 | isExternalName name = IfaceExt name
1552 | Just (TickBox m ix) <- isTickBoxOp_maybe v
1554 | otherwise = IfaceLcl (getFS name)