2 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
4 \section{Tidying up Core}
8 tidyCorePgm, tidyExpr, tidyCoreExpr,
12 #include "HsVersions.h"
14 import CmdLineOpts ( DynFlags, DynFlag(..), opt_OmitInterfacePragmas )
16 import CoreUnfold ( noUnfolding, mkTopUnfolding, okToUnfoldInHiFile )
17 import CoreFVs ( ruleLhsFreeIds, ruleRhsFreeVars, exprSomeFreeVars )
18 import PprCore ( pprIdCoreRule )
19 import CoreLint ( showPass, endPass )
20 import CoreUtils ( exprArity )
23 import Var ( Id, Var )
24 import Id ( idType, idInfo, idName, isExportedId,
25 idSpecialisation, idUnique,
26 mkVanillaGlobal, isLocalId,
27 isImplicitId, mkUserLocal, setIdInfo
29 import IdInfo {- loads of stuff -}
30 import NewDemand ( isBottomingSig, topSig )
31 import BasicTypes ( isNeverActive )
32 import Name ( getOccName, nameOccName, mkInternalName, mkExternalName,
33 localiseName, isExternalName, nameSrcLoc
35 import NameEnv ( filterNameEnv )
36 import OccName ( TidyOccEnv, initTidyOccEnv, tidyOccName )
37 import Type ( tidyTopType, tidyType, tidyTyVarBndr )
38 import Module ( Module, moduleName )
39 import HscTypes ( PersistentCompilerState( pcs_PRS ),
40 PersistentRenamerState( prsOrig ),
41 NameSupply( nsNames, nsUniqs ),
42 TypeEnv, extendTypeEnvList, typeEnvIds,
43 ModDetails(..), TyThing(..)
45 import FiniteMap ( lookupFM, addToFM )
46 import Maybes ( orElse )
47 import ErrUtils ( showPass, dumpIfSet_core )
48 import SrcLoc ( noSrcLoc )
49 import UniqFM ( mapUFM )
50 import UniqSupply ( splitUniqSupply, uniqFromSupply )
51 import List ( partition )
52 import Util ( mapAccumL )
53 import Maybe ( isJust )
59 %************************************************************************
61 \subsection{What goes on}
63 %************************************************************************
69 Step 1: Figure out external Ids
70 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
71 First we figure out which Ids are "external" Ids. An
72 "external" Id is one that is visible from outside the compilation
74 a) the user exported ones
75 b) ones mentioned in the unfoldings, workers,
76 or rules of externally-visible ones
77 This exercise takes a sweep of the bindings bottom to top. Actually,
78 in Step 2 we're also going to need to know which Ids should be
79 exported with their unfoldings, so we produce not an IdSet but an
83 Step 2: Tidy the program
84 ~~~~~~~~~~~~~~~~~~~~~~~~
85 Next we traverse the bindings top to bottom. For each *top-level*
88 1. Make it into a GlobalId
90 2. Give it a system-wide Unique.
91 [Even non-exported things need system-wide Uniques because the
92 byte-code generator builds a single Name->BCO symbol table.]
94 We use the NameSupply kept in the PersistentRenamerState as the
95 source of such system-wide uniques.
97 For external Ids, use the original-name cache in the NameSupply
98 to ensure that the unique assigned is the same as the Id had
99 in any previous compilation run.
101 3. If it's an external Id, make it have a global Name, otherwise
102 make it have a local Name.
103 This is used by the code generator to decide whether
104 to make the label externally visible
106 4. Give external Ids a "tidy" occurrence name. This means
107 we can print them in interface files without confusing
108 "x" (unique 5) with "x" (unique 10).
110 5. Give it its UTTERLY FINAL IdInfo; in ptic,
111 * Its IdDetails becomes VanillaGlobal, reflecting the fact that
112 from now on we regard it as a global, not local, Id
114 * its unfolding, if it should have one
116 * its arity, computed from the number of visible lambdas
118 * its CAF info, computed from what is free in its RHS
121 Finally, substitute these new top-level binders consistently
122 throughout, including in unfoldings. We also tidy binders in
123 RHSs, so that they print nicely in interfaces.
126 tidyCorePgm :: DynFlags -> Module
127 -> PersistentCompilerState
128 -> CgInfoEnv -- Information from the back end,
129 -- to be splatted into the IdInfo
131 -> IO (PersistentCompilerState, ModDetails)
133 tidyCorePgm dflags mod pcs cg_info_env
134 (ModDetails { md_types = env_tc, md_insts = insts_tc,
135 md_binds = binds_in, md_rules = orphans_in })
136 = do { showPass dflags "Tidy Core"
138 ; let ext_ids = findExternalSet binds_in orphans_in
139 ; let ext_rules = findExternalRules binds_in orphans_in ext_ids
140 -- findExternalRules filters ext_rules to avoid binders that
141 -- aren't externally visible; but the externally-visible binders
142 -- are computed (by findExternalSet) assuming that all orphan
143 -- rules are exported. So in fact we may export more than we
144 -- need. (It's a sort of mutual recursion.)
146 -- We also make sure to avoid any exported binders. Consider
147 -- f{-u1-} = 1 -- Local decl
149 -- f{-u2-} = 2 -- Exported decl
151 -- The second exported decl must 'get' the name 'f', so we
152 -- have to put 'f' in the avoids list before we get to the first
153 -- decl. tidyTopId then does a no-op on exported binders.
154 ; let prs = pcs_PRS pcs
155 orig_ns = prsOrig prs
157 init_tidy_env = (orig_ns, initTidyOccEnv avoids, emptyVarEnv)
158 avoids = [getOccName name | bndr <- typeEnvIds env_tc,
159 let name = idName bndr,
161 -- In computing our "avoids" list, we must include
163 -- all things with global names (assigned once and for
164 -- all by the renamer)
165 -- since their names are "taken".
166 -- The type environment is a convenient source of such things.
168 ; let ((orig_ns', occ_env, subst_env), tidy_binds)
169 = mapAccumL (tidyTopBind mod ext_ids cg_info_env)
170 init_tidy_env binds_in
172 ; let tidy_rules = tidyIdRules (occ_env,subst_env) ext_rules
174 ; let prs' = prs { prsOrig = orig_ns' }
175 pcs' = pcs { pcs_PRS = prs' }
177 ; let final_ids = [ id
179 , id <- bindersOf bind
180 , isExternalName (idName id)]
182 -- Dfuns are local Ids that might have
183 -- changed their unique during tidying
184 ; let lookup_dfun_id id = lookupVarEnv subst_env id `orElse`
185 pprPanic "lookup_dfun_id" (ppr id)
188 ; let tidy_type_env = mkFinalTypeEnv env_tc final_ids
189 tidy_dfun_ids = map lookup_dfun_id insts_tc
191 ; let tidy_details = ModDetails { md_types = tidy_type_env,
192 md_rules = tidy_rules,
193 md_insts = tidy_dfun_ids,
194 md_binds = tidy_binds }
196 ; endPass dflags "Tidy Core" Opt_D_dump_simpl tidy_binds
197 ; dumpIfSet_core dflags Opt_D_dump_simpl
199 (vcat (map pprIdCoreRule tidy_rules))
201 ; return (pcs', tidy_details)
204 tidyCoreExpr :: CoreExpr -> IO CoreExpr
205 tidyCoreExpr expr = return (tidyExpr emptyTidyEnv expr)
209 %************************************************************************
211 \subsection{Write a new interface file}
213 %************************************************************************
216 mkFinalTypeEnv :: TypeEnv -- From typechecker
220 mkFinalTypeEnv type_env final_ids
221 = extendTypeEnvList (filterNameEnv keep_it type_env)
224 -- The competed type environment is gotten from
225 -- a) keeping the types and classes
226 -- b) removing all Ids,
227 -- c) adding Ids with correct IdInfo, including unfoldings,
228 -- gotten from the bindings
229 -- From (c) we keep only those Ids with Global names;
230 -- the CoreTidy pass makes sure these are all and only
231 -- the externally-accessible ones
232 -- This truncates the type environment to include only the
233 -- exported Ids and things needed from them, which saves space
235 -- However, we do keep things like constructors, which should not appear
236 -- in interface files, because they are needed by importing modules when
237 -- using the compilation manager
239 -- We keep implicit Ids, because they won't appear
240 -- in the bindings from which final_ids are derived!
241 keep_it (AnId id) = isImplicitId id -- Remove all Ids except implicit ones
242 keep_it other = True -- Keep all TyCons and Classes
246 findExternalRules :: [CoreBind]
247 -> [IdCoreRule] -- Orphan rules
248 -> IdEnv a -- Ids that are exported, so we need their rules
250 -- The complete rules are gotten by combining
251 -- a) the orphan rules
252 -- b) rules embedded in the top-level Ids
253 findExternalRules binds orphan_rules ext_ids
254 | opt_OmitInterfacePragmas = []
256 = filter needed_rule (orphan_rules ++ local_rules)
258 local_rules = [ (id, rule)
259 | id <- bindersOfBinds binds,
260 id `elemVarEnv` ext_ids,
261 rule <- rulesRules (idSpecialisation id)
263 needed_rule (id, rule)
264 = not (isBuiltinRule rule)
265 -- We can't print builtin rules in interface files
266 -- Since they are built in, an importing module
267 -- will have access to them anyway
269 && not (any internal_id (varSetElems (ruleLhsFreeIds rule)))
270 -- Don't export a rule whose LHS mentions an Id that
271 -- is completely internal (i.e. not visible to an
274 internal_id id = isLocalId id && not (id `elemVarEnv` ext_ids)
277 %************************************************************************
279 \subsection{Step 1: finding externals}
281 %************************************************************************
284 findExternalSet :: [CoreBind] -> [IdCoreRule]
285 -> IdEnv Bool -- In domain => external
286 -- Range = True <=> show unfolding
287 -- Step 1 from the notes above
288 findExternalSet binds orphan_rules
289 = foldr find init_needed binds
291 orphan_rule_ids :: IdSet
292 orphan_rule_ids = unionVarSets [ ruleRhsFreeVars rule
293 | (_, rule) <- orphan_rules]
294 init_needed :: IdEnv Bool
295 init_needed = mapUFM (\_ -> False) orphan_rule_ids
296 -- The mapUFM is a bit cheesy. It is a cheap way
297 -- to turn the set of orphan_rule_ids, which we use to initialise
298 -- the sweep, into a mapping saying 'don't expose unfolding'
299 -- (When we come to the binding site we may change our mind, of course.)
301 find (NonRec id rhs) needed
302 | need_id needed id = addExternal (id,rhs) needed
304 find (Rec prs) needed = find_prs prs needed
306 -- For a recursive group we have to look for a fixed point
308 | null needed_prs = needed
309 | otherwise = find_prs other_prs new_needed
311 (needed_prs, other_prs) = partition (need_pr needed) prs
312 new_needed = foldr addExternal needed needed_prs
314 -- The 'needed' set contains the Ids that are needed by earlier
315 -- interface file emissions. If the Id isn't in this set, and isn't
316 -- exported, there's no need to emit anything
317 need_id needed_set id = id `elemVarEnv` needed_set || isExportedId id
318 need_pr needed_set (id,rhs) = need_id needed_set id
320 addExternal :: (Id,CoreExpr) -> IdEnv Bool -> IdEnv Bool
321 -- The Id is needed; extend the needed set
322 -- with it and its dependents (free vars etc)
323 addExternal (id,rhs) needed
324 = extendVarEnv (foldVarSet add_occ needed new_needed_ids)
327 add_occ id needed = extendVarEnv needed id False
328 -- "False" because we don't know we need the Id's unfolding
329 -- We'll override it later when we find the binding site
331 new_needed_ids | opt_OmitInterfacePragmas = emptyVarSet
332 | otherwise = worker_ids `unionVarSet`
333 unfold_ids `unionVarSet`
337 dont_inline = isNeverActive (inlinePragInfo idinfo)
338 loop_breaker = isLoopBreaker (occInfo idinfo)
339 bottoming_fn = isBottomingSig (newStrictnessInfo idinfo `orElse` topSig)
340 spec_ids = rulesRhsFreeVars (specInfo idinfo)
341 worker_info = workerInfo idinfo
343 -- Stuff to do with the Id's unfolding
344 -- The simplifier has put an up-to-date unfolding
345 -- in the IdInfo, but the RHS will do just as well
346 unfolding = unfoldingInfo idinfo
347 rhs_is_small = not (neverUnfold unfolding)
349 -- We leave the unfolding there even if there is a worker
350 -- In GHCI the unfolding is used by importers
351 -- When writing an interface file, we omit the unfolding
352 -- if there is a worker
353 show_unfold = not bottoming_fn && -- Not necessary
356 rhs_is_small && -- Small enough
357 okToUnfoldInHiFile rhs -- No casms etc
359 unfold_ids | show_unfold = exprSomeFreeVars isLocalId rhs
360 | otherwise = emptyVarSet
362 worker_ids = case worker_info of
363 HasWorker work_id _ -> unitVarSet work_id
364 otherwise -> emptyVarSet
368 %************************************************************************
370 \subsection{Step 2: top-level tidying}
372 %************************************************************************
376 type TopTidyEnv = (NameSupply, TidyOccEnv, VarEnv Var)
378 -- TopTidyEnv: when tidying we need to know
379 -- * ns: The NameSupply, containing a unique supply and any pre-ordained Names.
380 -- These may have arisen because the
381 -- renamer read in an interface file mentioning M.$wf, say,
382 -- and assigned it unique r77. If, on this compilation, we've
383 -- invented an Id whose name is $wf (but with a different unique)
384 -- we want to rename it to have unique r77, so that we can do easy
385 -- comparisons with stuff from the interface file
387 -- * occ_env: The TidyOccEnv, which tells us which local occurrences
390 -- * subst_env: A Var->Var mapping that substitutes the new Var for the old
395 tidyTopBind :: Module
396 -> IdEnv Bool -- Domain = Ids that should be external
397 -- True <=> their unfolding is external too
399 -> TopTidyEnv -> CoreBind
400 -> (TopTidyEnv, CoreBind)
402 tidyTopBind mod ext_ids cg_info_env top_tidy_env (NonRec bndr rhs)
403 = ((orig,occ,subst) , NonRec bndr' rhs')
405 ((orig,occ,subst), bndr')
406 = tidyTopBinder mod ext_ids cg_info_env
407 rec_tidy_env rhs rhs' top_tidy_env bndr
408 rec_tidy_env = (occ,subst)
409 rhs' = tidyExpr rec_tidy_env rhs
411 tidyTopBind mod ext_ids cg_info_env top_tidy_env (Rec prs)
412 = (final_env, Rec prs')
414 (final_env@(_,occ,subst), prs') = mapAccumL do_one top_tidy_env prs
415 rec_tidy_env = (occ,subst)
417 do_one top_tidy_env (bndr,rhs)
418 = ((orig,occ,subst), (bndr',rhs'))
420 ((orig,occ,subst), bndr')
421 = tidyTopBinder mod ext_ids cg_info_env
422 rec_tidy_env rhs rhs' top_tidy_env bndr
424 rhs' = tidyExpr rec_tidy_env rhs
426 tidyTopBinder :: Module -> IdEnv Bool -> CgInfoEnv
427 -> TidyEnv -- The TidyEnv is used to tidy the IdInfo
428 -> CoreExpr -- RHS *before* tidying
429 -> CoreExpr -- RHS *after* tidying
430 -- The TidyEnv and the after-tidying RHS are
431 -- both are knot-tied: don't look at them!
432 -> TopTidyEnv -> Id -> (TopTidyEnv, Id)
433 -- NB: tidyTopBinder doesn't affect the unique supply
435 tidyTopBinder mod ext_ids cg_info_env rec_tidy_env rhs tidy_rhs
436 env@(ns2, occ_env2, subst_env2) id
437 -- This function is the heart of Step 2
438 -- The rec_tidy_env is the one to use for the IdInfo
439 -- It's necessary because when we are dealing with a recursive
440 -- group, a variable late in the group might be mentioned
441 -- in the IdInfo of one early in the group
443 -- The rhs is already tidied
445 = ((orig_env', occ_env', subst_env'), id')
447 (orig_env', occ_env', name') = tidyTopName mod ns2 occ_env2
450 ty' = tidyTopType (idType id)
451 idinfo = tidyTopIdInfo rec_tidy_env is_external
452 (idInfo id) unfold_info arity
453 (lookupCgInfo cg_info_env name')
455 id' = mkVanillaGlobal name' ty' idinfo
457 subst_env' = extendVarEnv subst_env2 id id'
459 maybe_external = lookupVarEnv ext_ids id
460 is_external = isJust maybe_external
462 -- Expose an unfolding if ext_ids tells us to
463 -- Remember that ext_ids maps an Id to a Bool:
464 -- True to show the unfolding, False to hide it
465 show_unfold = maybe_external `orElse` False
466 unfold_info | show_unfold = mkTopUnfolding tidy_rhs
467 | otherwise = noUnfolding
469 -- Usually the Id will have an accurate arity on it, because
470 -- the simplifier has just run, but not always.
471 -- One case I found was when the last thing the simplifier
472 -- did was to let-bind a non-atomic argument and then float
473 -- it to the top level. So it seems more robust just to
475 arity = exprArity rhs
479 -- tidyTopIdInfo creates the final IdInfo for top-level
480 -- binders. There are two delicate pieces:
482 -- * Arity. After CoreTidy, this arity must not change any more.
483 -- Indeed, CorePrep must eta expand where necessary to make
484 -- the manifest arity equal to the claimed arity.
486 -- * CAF info, which comes from the CoreToStg pass via a knot.
487 -- The CAF info will not be looked at by the downstream stuff:
488 -- it *generates* it, and knot-ties it back. It will only be
489 -- looked at by (a) MkIface when generating an interface file
490 -- (b) In GHCi, importing modules
491 -- Nevertheless, we add the info here so that it propagates to all
492 -- occurrences of the binders in RHSs, and hence to occurrences in
493 -- unfoldings, which are inside Ids imported by GHCi. Ditto RULES.
495 -- An alterative would be to do a second pass over the unfoldings
496 -- of Ids, and rules, right at the top, but that would be a pain.
498 tidyTopIdInfo tidy_env is_external idinfo unfold_info arity cg_info
499 | opt_OmitInterfacePragmas || not is_external
500 -- Only basic info if the Id isn't external, or if we don't have -O
503 | otherwise -- Add extra optimisation info
505 `setInlinePragInfo` inlinePragInfo idinfo
506 `setUnfoldingInfo` unfold_info
507 `setWorkerInfo` tidyWorker tidy_env (workerInfo idinfo)
508 -- NB: we throw away the Rules
509 -- They have already been extracted by findExternalRules
512 -- baasic_info is attached to every top-level binder
513 basic_info = vanillaIdInfo
516 `setAllStrictnessInfo` newStrictnessInfo idinfo
518 -- This is where we set names to local/global based on whether they really are
519 -- externally visible (see comment at the top of this module). If the name
520 -- was previously local, we have to give it a unique occurrence name if
521 -- we intend to externalise it.
522 tidyTopName mod ns occ_env external name
523 | global && internal = (ns, occ_env, localiseName name)
525 | global && external = (ns, occ_env, name)
526 -- Global names are assumed to have been allocated by the renamer,
527 -- so they already have the "right" unique
528 -- And it's a system-wide unique too
530 | local && internal = (ns_w_local, occ_env', new_local_name)
531 -- Even local, internal names must get a unique occurrence, because
532 -- if we do -split-objs we externalise the name later, in the code generator
534 -- Similarly, we must make sure it has a system-wide Unique, because
535 -- the byte-code generator builds a system-wide Name->BCO symbol table
537 | local && external = case lookupFM ns_names key of
538 Just orig -> (ns, occ_env', orig)
539 Nothing -> (ns_w_global, occ_env', new_external_name)
540 -- If we want to externalise a currently-local name, check
541 -- whether we have already assigned a unique for it.
542 -- If so, use it; if not, extend the table (ns_w_global).
543 -- This is needed when *re*-compiling a module in GHCi; we want to
544 -- use the same name for externally-visible things as we did before.
547 global = isExternalName name
549 internal = not external
551 (occ_env', occ') = tidyOccName occ_env (nameOccName name)
552 key = (moduleName mod, occ')
553 ns_names = nsNames ns
554 ns_uniqs = nsUniqs ns
555 (us1, us2) = splitUniqSupply ns_uniqs
556 uniq = uniqFromSupply us1
557 loc = nameSrcLoc name
559 new_local_name = mkInternalName uniq occ' loc
560 new_external_name = mkExternalName uniq mod occ' loc
562 ns_w_local = ns { nsUniqs = us2 }
563 ns_w_global = ns { nsUniqs = us2, nsNames = addToFM ns_names key new_external_name }
566 ------------ Worker --------------
567 tidyWorker tidy_env (HasWorker work_id wrap_arity)
568 = HasWorker (tidyVarOcc tidy_env work_id) wrap_arity
569 tidyWorker tidy_env other
572 ------------ Rules --------------
573 tidyIdRules :: TidyEnv -> [IdCoreRule] -> [IdCoreRule]
574 tidyIdRules env [] = []
575 tidyIdRules env ((fn,rule) : rules)
576 = tidyRule env rule =: \ rule ->
577 tidyIdRules env rules =: \ rules ->
578 ((tidyVarOcc env fn, rule) : rules)
580 tidyRule :: TidyEnv -> CoreRule -> CoreRule
581 tidyRule env rule@(BuiltinRule _ _) = rule
582 tidyRule env (Rule name act vars tpl_args rhs)
583 = tidyBndrs env vars =: \ (env', vars) ->
584 map (tidyExpr env') tpl_args =: \ tpl_args ->
585 (Rule name act vars tpl_args (tidyExpr env' rhs))
588 %************************************************************************
590 \subsection{Step 2: inner tidying
592 %************************************************************************
597 -> (TidyEnv, CoreBind)
599 tidyBind env (NonRec bndr rhs)
600 = tidyLetBndr env (bndr,rhs) =: \ (env', bndr') ->
601 (env', NonRec bndr' (tidyExpr env' rhs))
603 tidyBind env (Rec prs)
604 = mapAccumL tidyLetBndr env prs =: \ (env', bndrs') ->
605 map (tidyExpr env') (map snd prs) =: \ rhss' ->
606 (env', Rec (zip bndrs' rhss'))
609 tidyExpr env (Var v) = Var (tidyVarOcc env v)
610 tidyExpr env (Type ty) = Type (tidyType env ty)
611 tidyExpr env (Lit lit) = Lit lit
612 tidyExpr env (App f a) = App (tidyExpr env f) (tidyExpr env a)
613 tidyExpr env (Note n e) = Note (tidyNote env n) (tidyExpr env e)
615 tidyExpr env (Let b e)
616 = tidyBind env b =: \ (env', b') ->
617 Let b' (tidyExpr env' e)
619 tidyExpr env (Case e b alts)
620 = tidyBndr env b =: \ (env', b) ->
621 Case (tidyExpr env e) b (map (tidyAlt env') alts)
623 tidyExpr env (Lam b e)
624 = tidyBndr env b =: \ (env', b) ->
625 Lam b (tidyExpr env' e)
628 tidyAlt env (con, vs, rhs)
629 = tidyBndrs env vs =: \ (env', vs) ->
630 (con, vs, tidyExpr env' rhs)
632 tidyNote env (Coerce t1 t2) = Coerce (tidyType env t1) (tidyType env t2)
633 tidyNote env note = note
637 %************************************************************************
639 \subsection{Tidying up non-top-level binders}
641 %************************************************************************
644 tidyVarOcc (_, var_env) v = case lookupVarEnv var_env v of
648 -- tidyBndr is used for lambda and case binders
649 tidyBndr :: TidyEnv -> Var -> (TidyEnv, Var)
651 | isTyVar var = tidyTyVarBndr env var
652 | otherwise = tidyIdBndr env var
654 tidyBndrs :: TidyEnv -> [Var] -> (TidyEnv, [Var])
655 tidyBndrs env vars = mapAccumL tidyBndr env vars
657 tidyLetBndr :: TidyEnv -> (Id, CoreExpr) -> (TidyEnv, Var)
658 -- Used for local (non-top-level) let(rec)s
659 tidyLetBndr env (id,rhs)
660 = ((tidy_env,new_var_env), final_id)
662 ((tidy_env,var_env), new_id) = tidyIdBndr env id
664 -- We need to keep around any interesting strictness and demand info
665 -- because later on we may need to use it when converting to A-normal form.
667 -- f (g x), where f is strict in its argument, will be converted
668 -- into case (g x) of z -> f z by CorePrep, but only if f still
669 -- has its strictness info.
671 -- Similarly for the demand info - on a let binder, this tells
672 -- CorePrep to turn the let into a case.
674 -- Similarly arity info for eta expansion in CorePrep
675 final_id = new_id `setIdInfo` new_info
677 new_info = vanillaIdInfo
678 `setArityInfo` exprArity rhs
679 `setAllStrictnessInfo` newStrictnessInfo idinfo
680 `setNewDemandInfo` newDemandInfo idinfo
682 -- Override the env we get back from tidyId with the new IdInfo
683 -- so it gets propagated to the usage sites.
684 new_var_env = extendVarEnv var_env id final_id
686 -- Non-top-level variables
687 tidyIdBndr :: TidyEnv -> Id -> (TidyEnv, Id)
688 tidyIdBndr env@(tidy_env, var_env) id
689 = -- do this pattern match strictly, otherwise we end up holding on to
690 -- stuff in the OccName.
691 case tidyOccName tidy_env (getOccName id) of { (tidy_env', occ') ->
693 -- Give the Id a fresh print-name, *and* rename its type
694 -- The SrcLoc isn't important now,
695 -- though we could extract it from the Id
697 -- All nested Ids now have the same IdInfo, namely none,
698 -- which should save some space.
699 ty' = tidyType env (idType id)
700 id' = mkUserLocal occ' (idUnique id) ty' noSrcLoc
701 var_env' = extendVarEnv var_env id id'
703 ((tidy_env', var_env'), id')