-\subsection{Step 2: top-level tidying}
-%* *
-%************************************************************************
-
-
-\begin{code}
-type TopTidyEnv = (UniqSupply, OrigNameNameEnv, TidyOccEnv, VarEnv Var)
-
--- TopTidyEnv: when tidying we need to know
--- * orig_env: Any pre-ordained Names. These may have arisen because the
--- renamer read in an interface file mentioning M.$wf, say,
--- and assigned it unique r77. If, on this compilation, we've
--- invented an Id whose name is $wf (but with a different unique)
--- we want to rename it to have unique r77, so that we can do easy
--- comparisons with stuff from the interface file
---
--- * occ_env: The TidyOccEnv, which tells us which local occurrences
--- are 'used'
---
--- * subst_env: A Var->Var mapping that substitutes the new Var for the old
---
--- * uniqsuppy: so we can clone any Ids with non-preordained names.
---
-\end{code}
-
-
-\begin{code}
-tidyTopBind :: Module
- -> IdEnv Bool -- Domain = Ids that should be external
- -- True <=> their unfolding is external too
- -> TopTidyEnv -> CoreBind
- -> (TopTidyEnv, CoreBind)
-
-tidyTopBind mod ext_ids env (NonRec bndr rhs)
- = ((us2,orig,occ,subst) , NonRec bndr' rhs')
- where
- (env1@(us1,orig,occ,subst), bndr') = tidyTopBinder mod ext_ids env rhs' env bndr
- (rhs',us2) = initUs us1 (tidyTopRhs env1 rhs)
-
-tidyTopBind mod ext_ids env (Rec prs)
- = (final_env, Rec prs')
- where
- (final_env, prs') = mapAccumL do_one env prs
-
- do_one env (bndr,rhs)
- = ((us',orig,occ,subst), (bndr',rhs'))
- where
- (env'@(us,orig,occ,subst), bndr')
- = tidyTopBinder mod ext_ids final_env rhs' env bndr
- (rhs', us') = initUs us (tidyTopRhs final_env rhs)
-
-
-tidyTopRhs :: TopTidyEnv -> CoreExpr -> UniqSM CoreExpr
- -- Just an impedence matcher
-tidyTopRhs (_, _, occ_env, subst_env) rhs
- = tidyExpr (occ_env, subst_env) rhs
-
-
-tidyTopBinder :: Module -> IdEnv Bool
- -> TopTidyEnv -> CoreExpr
- -> TopTidyEnv -> Id -> (TopTidyEnv, Id)
-tidyTopBinder mod ext_ids
- final_env@(_, orig_env1, occ_env1, subst_env1) rhs
- env@(us, orig_env2, occ_env2, subst_env2) id
-
- | omitIfaceSigForId id -- Don't mess with constructors,
- = (env, id) -- record selectors, and the like
-
- | otherwise
- -- This function is the heart of Step 2
- -- The second env is the one to use for the IdInfo
- -- It's necessary because when we are dealing with a recursive
- -- group, a variable late in the group might be mentioned
- -- in the IdInfo of one early in the group
-
- -- The rhs is already tidied
-
- = ((us_r, orig_env', occ_env', subst_env'), id')
- where
- (us_l, us_r) = splitUniqSupply us
-
- (orig_env', occ_env', name') = tidyTopName mod orig_env2 occ_env2
- is_external
- (idName id)
- ty' = tidyTopType (idType id)
- idinfo' = tidyIdInfo us_l (occ_env1, subst_env1)
- is_external unfold_info arity_info id
-
- id' = mkId name' ty' idinfo'
- subst_env' = extendVarEnv subst_env2 id id'
-
- maybe_external = lookupVarEnv ext_ids id
- is_external = maybeToBool maybe_external
-
- -- Expose an unfolding if ext_ids tells us to
- show_unfold = maybe_external `orElse` False
- unfold_info | show_unfold = mkTopUnfolding rhs
- | otherwise = noUnfolding
-
- arity_info = exprArity rhs
-
-
-tidyIdInfo us tidy_env is_external unfold_info arity_info id
- | opt_OmitInterfacePragmas || not is_external
- -- No IdInfo if the Id isn't external, or if we don't have -O
- = mkIdInfo new_flavour
- `setStrictnessInfo` strictnessInfo core_idinfo
- `setArityInfo` ArityExactly arity_info
- -- Keep strictness and arity info; it's used by the code generator
-
- | otherwise
- = let (rules', _) = initUs us (tidyRules tidy_env (specInfo core_idinfo))
- in
- mkIdInfo new_flavour
- `setCprInfo` cprInfo core_idinfo
- `setStrictnessInfo` strictnessInfo core_idinfo
- `setInlinePragInfo` inlinePragInfo core_idinfo
- `setUnfoldingInfo` unfold_info
- `setWorkerInfo` tidyWorker tidy_env (workerInfo core_idinfo)
- `setSpecInfo` rules'
- `setArityInfo` ArityExactly arity_info
- -- this is the final IdInfo, it must agree with the
- -- code finally generated (i.e. NO more transformations
- -- after this!).
- where
- core_idinfo = idInfo id
-
- -- A DFunId must stay a DFunId, so that we can gather the
- -- DFunIds up later. Other local things become ConstantIds.
- new_flavour = case flavourInfo core_idinfo of
- VanillaId -> ConstantId
- ExportedId -> ConstantId
- ConstantId -> ConstantId -- e.g. Default methods
- DictFunId -> DictFunId
- flavour -> pprTrace "tidyIdInfo" (ppr id <+> ppFlavourInfo flavour)
- flavour
-
--- this is where we set names to local/global based on whether they really are
--- externally visible (see comment at the top of this module). If the name
--- was previously local, we have to give it a unique occurrence name if
--- we intend to globalise it.
-tidyTopName mod orig_env occ_env external name
- | global && internal = (orig_env, occ_env, localiseName name)
- | local && internal = (orig_env, occ_env', setNameOcc name occ') -- (*)
- | global && external = (orig_env, occ_env, name)
- | local && external = globalise
- -- (*) just in case we're globalising all top-level names (because of
- -- -split-objs), we need to give *all* the top-level ids a
- -- unique occurrence name. The actual globalisation now happens in the code
- -- generator.
- where
- -- If we want to globalise a currently-local name, check
- -- whether we have already assigned a unique for it.
- -- If so, use it; if not, extend the table
- globalise
- = case lookupFM orig_env key of
- Just orig -> (orig_env, occ_env', orig)
- Nothing -> (addToFM orig_env key global_name, occ_env', global_name)
-
- (occ_env', occ') = tidyOccName occ_env (nameOccName name)
- key = (moduleName mod, occ')
- global_name = globaliseName (setNameOcc name occ') mod
- global = isGlobalName name
- local = not global
- internal = not external
-
-tidyIdRules :: TidyEnv -> [IdCoreRule] -> UniqSM [IdCoreRule]
-tidyIdRules env [] = returnUs []
-tidyIdRules env ((fn,rule) : rules)
- = tidyRule env rule `thenUs` \ rule ->
- tidyIdRules env rules `thenUs` \ rules ->
- returnUs ((tidyVarOcc env fn, rule) : rules)
-
-tidyWorker tidy_env (HasWorker work_id wrap_arity)
- = HasWorker (tidyVarOcc tidy_env work_id) wrap_arity
-tidyWorker tidy_env NoWorker
- = NoWorker
-
-tidyRules :: TidyEnv -> CoreRules -> UniqSM CoreRules
-tidyRules env (Rules rules fvs)
- = mapUs (tidyRule env) rules `thenUs` \ rules ->
- returnUs (Rules rules (foldVarSet tidy_set_elem emptyVarSet fvs))
- where
- tidy_set_elem var new_set = extendVarSet new_set (tidyVarOcc env var)
-
-tidyRule :: TidyEnv -> CoreRule -> UniqSM CoreRule
-tidyRule env rule@(BuiltinRule _) = returnUs rule
-tidyRule env (Rule name vars tpl_args rhs)
- = tidyBndrs env vars `thenUs` \ (env', vars) ->
- mapUs (tidyExpr env') tpl_args `thenUs` \ tpl_args ->
- tidyExpr env' rhs `thenUs` \ rhs ->
- returnUs (Rule name vars tpl_args rhs)
-\end{code}
-
-%************************************************************************
-%* *
-\subsection{Step 2: inner tidying