1 (c) The University of Glasgow 2002
5 newGlobalBinder, newIPName, newImplicitBinder,
6 lookupIfaceTop, lookupIfaceExt,
7 lookupOrig, lookupAvail, lookupIfaceTc,
8 newIfaceName, newIfaceNames,
9 extendIfaceIdEnv, extendIfaceTyVarEnv,
10 tcIfaceLclId, tcIfaceTyVar,
13 allocateGlobalBinder, initNameCache,
16 #include "HsVersions.h"
19 import IfaceType ( IfaceExtName(..), IfaceTyCon(..), ifaceTyConName )
20 import TysWiredIn ( tupleTyCon, tupleCon )
21 import HscTypes ( NameCache(..), HscEnv(..), GenAvailInfo(..), OrigNameCache )
22 import TyCon ( TyCon, tyConName )
23 import DataCon ( dataConWorkId, dataConName )
24 import Var ( TyVar, Id, varName )
25 import Name ( Name, nameUnique, nameModule,
26 nameOccName, nameSrcLoc,
27 getOccName, nameParent_maybe,
28 isWiredInName, mkIPName,
29 mkExternalName, mkInternalName )
31 import OccName ( OccName, isTupleOcc_maybe, tcName, dataName,
32 lookupOccEnv, unitOccEnv, extendOccEnv, extendOccEnvList )
33 import PrelNames ( gHC_PRIM, pREL_TUP )
34 import Module ( Module, emptyModuleEnv,
35 lookupModuleEnv, extendModuleEnv_C )
36 import UniqSupply ( UniqSupply, splitUniqSupply, uniqFromSupply, uniqsFromSupply )
37 import FiniteMap ( emptyFM, lookupFM, addToFM )
38 import BasicTypes ( IPName(..), mapIPName )
39 import SrcLoc ( SrcLoc, noSrcLoc )
40 import Maybes ( orElse )
46 %*********************************************************
48 Allocating new Names in the Name Cache
50 %*********************************************************
53 newGlobalBinder :: Module -> OccName -> Maybe Name -> SrcLoc -> TcRnIf a b Name
54 -- Used for source code and interface files, to make the
55 -- Name for a thing, given its Module and OccName
57 -- The cache may already already have a binding for this thing,
58 -- because we may have seen an occurrence before, but now is the
59 -- moment when we know its Module and SrcLoc in their full glory
61 newGlobalBinder mod occ mb_parent loc
62 = do { mod `seq` occ `seq` return () -- See notes with lookupOrig_help
63 ; traceIf (text "newGlobalBinder" <+> ppr mod <+> ppr occ <+> ppr loc)
64 ; name_supply <- getNameCache
65 ; let (name_supply', name) = allocateGlobalBinder
68 ; setNameCache name_supply'
73 -> Module -> OccName -> Maybe Name -> SrcLoc
75 allocateGlobalBinder name_supply mod occ mb_parent loc
76 = case lookupOrigNameCache (nsNames name_supply) mod occ of
77 -- A hit in the cache! We are at the binding site of the name.
78 -- This is the moment when we know the defining parent and SrcLoc
79 -- of the Name, so we set these fields in the Name we return.
81 -- Then (bogus) multiple bindings of the same Name
82 -- get different SrcLocs can can be reported as such.
84 -- Possible other reason: it might be in the cache because we
85 -- encountered an occurrence before the binding site for an
86 -- implicitly-imported Name. Perhaps the current SrcLoc is
87 -- better... but not really: it'll still just say 'imported'
89 -- IMPORTANT: Don't mess with wired-in names.
90 -- Their wired-in-ness is in their NameSort
91 -- and their Module is correct.
93 Just name | isWiredInName name -> (name_supply, name)
94 | otherwise -> (new_name_supply, name')
96 uniq = nameUnique name
97 name' = mkExternalName uniq mod occ mb_parent loc
98 new_cache = extend_name_cache (nsNames name_supply) mod occ name'
99 new_name_supply = name_supply {nsNames = new_cache}
101 -- Miss in the cache!
102 -- Build a completely new Name, and put it in the cache
103 Nothing -> (new_name_supply, name)
105 (us', us1) = splitUniqSupply (nsUniqs name_supply)
106 uniq = uniqFromSupply us1
107 name = mkExternalName uniq mod occ mb_parent loc
108 new_cache = extend_name_cache (nsNames name_supply) mod occ name
109 new_name_supply = name_supply {nsUniqs = us', nsNames = new_cache}
112 newImplicitBinder :: Name -- Base name
113 -> (OccName -> OccName) -- Occurrence name modifier
114 -> TcRnIf m n Name -- Implicit name
115 -- Called in BuildTyCl to allocate the implicit binders of type/class decls
116 -- For source type/class decls, this is the first occurrence
117 -- For iface ones, the LoadIface has alrady allocated a suitable name in the cache
119 -- An *implicit* name has the base-name as parent
120 newImplicitBinder base_name mk_sys_occ
121 = newGlobalBinder (nameModule base_name)
122 (mk_sys_occ (nameOccName base_name))
124 (nameSrcLoc base_name)
126 parent_name = case nameParent_maybe base_name of
127 Just parent_name -> parent_name
130 lookupAvail :: Module -> GenAvailInfo OccName -> TcRnIf a b [Name]
131 -- Find all the names arising from an import
132 -- Make sure the parent info is correct, even though we may not
133 -- yet have read the interface for this module
134 lookupAvail mod (Avail n) = do { n' <- lookupOrig mod n;
136 lookupAvail mod (AvailTC p_occ occs)
137 = do { p_name <- lookupOrig mod p_occ
138 ; let lookup_sub occ | occ == p_occ = return p_name
139 | otherwise = lookup_orig mod occ (Just p_name)
140 ; mappM lookup_sub occs }
141 -- Remember that 'occs' is all the exported things, including
142 -- the parent. It's possible to export just class ops without
143 -- the class, via C( op ). If the class was exported too we'd
146 -- The use of lookupOrigSub here (rather than lookupOrig)
147 -- ensures that the subordinate names record their parent;
148 -- and that in turn ensures that the GlobalRdrEnv
149 -- has the correct parent for all the names in its range.
150 -- For imported things, we may only suck in the interface later, if ever.
151 -- Reason for all this:
152 -- Suppose module M exports type A.T, and constructor A.MkT
153 -- Then, we know that A.MkT is a subordinate name of A.T,
154 -- even though we aren't at the binding site of A.T
155 -- And it's important, because we may simply re-export A.T
156 -- without ever sucking in the declaration itself.
159 lookupOrig :: Module -> OccName -> TcRnIf a b Name
160 -- Even if we get a miss in the original-name cache, we
161 -- make a new External Name.
163 -- SrcLoc to noSrcLoc
165 -- They'll be overwritten, in due course, by LoadIface.loadDecl.
166 lookupOrig mod occ = lookup_orig mod occ Nothing
168 lookup_orig :: Module -> OccName -> Maybe Name -> TcRnIf a b Name
169 -- Used when we know the parent of the thing we are looking up
170 lookup_orig mod occ mb_parent
171 = do { -- First ensure that mod and occ are evaluated
172 -- If not, chaos can ensue:
173 -- we read the name-cache
174 -- then pull on mod (say)
175 -- which does some stuff that modifies the name cache
176 -- This did happen, with tycon_mod in TcIface.tcIfaceAlt (DataAlt..)
177 mod `seq` occ `seq` return ()
179 ; name_supply <- getNameCache
180 ; case lookupOrigNameCache (nsNames name_supply) mod occ of {
181 Just name -> returnM name ;
184 { let { (us', us1) = splitUniqSupply (nsUniqs name_supply)
185 ; uniq = uniqFromSupply us1
186 ; name = mkExternalName uniq mod occ mb_parent noSrcLoc
187 ; new_cache = extend_name_cache (nsNames name_supply) mod occ name
188 ; new_name_supply = name_supply {nsUniqs = us', nsNames = new_cache}
190 ; setNameCache new_name_supply
194 newIPName :: IPName OccName -> TcRnIf m n (IPName Name)
195 newIPName occ_name_ip
196 = getNameCache `thenM` \ name_supply ->
198 ipcache = nsIPs name_supply
200 case lookupFM ipcache key of
201 Just name_ip -> returnM name_ip
202 Nothing -> setNameCache new_ns `thenM_`
205 (us', us1) = splitUniqSupply (nsUniqs name_supply)
206 uniq = uniqFromSupply us1
207 name_ip = mapIPName (mkIPName uniq) occ_name_ip
208 new_ipcache = addToFM ipcache key name_ip
209 new_ns = name_supply {nsUniqs = us', nsIPs = new_ipcache}
211 key = occ_name_ip -- Ensures that ?x and %x get distinct Names
214 Local helper functions (not exported)
217 lookupOrigNameCache :: OrigNameCache -> Module -> OccName -> Maybe Name
218 lookupOrigNameCache nc mod occ
219 | mod == pREL_TUP || mod == gHC_PRIM, -- Boxed tuples from one,
220 Just tup_info <- isTupleOcc_maybe occ -- unboxed from the other
221 = -- Special case for tuples; there are too many
222 -- of them to pre-populate the original-name cache
223 Just (mk_tup_name tup_info)
225 mk_tup_name (ns, boxity, arity)
226 | ns == tcName = tyConName (tupleTyCon boxity arity)
227 | ns == dataName = dataConName (tupleCon boxity arity)
228 | otherwise = varName (dataConWorkId (tupleCon boxity arity))
230 lookupOrigNameCache nc mod occ -- The normal case
231 = case lookupModuleEnv nc mod of
233 Just occ_env -> lookupOccEnv occ_env occ
235 extendOrigNameCache :: OrigNameCache -> Name -> OrigNameCache
236 extendOrigNameCache nc name
237 = extend_name_cache nc (nameModule name) (nameOccName name) name
239 extend_name_cache :: OrigNameCache -> Module -> OccName -> Name -> OrigNameCache
240 extend_name_cache nc mod occ name
241 = extendModuleEnv_C combine nc mod (unitOccEnv occ name)
243 combine occ_env _ = extendOccEnv occ_env occ name
245 getNameCache :: TcRnIf a b NameCache
246 getNameCache = do { HscEnv { hsc_NC = nc_var } <- getTopEnv;
249 setNameCache :: NameCache -> TcRnIf a b ()
250 setNameCache nc = do { HscEnv { hsc_NC = nc_var } <- getTopEnv;
251 writeMutVar nc_var nc }
256 initNameCache :: UniqSupply -> [Name] -> NameCache
257 initNameCache us names
258 = NameCache { nsUniqs = us,
259 nsNames = initOrigNames names,
262 initOrigNames :: [Name] -> OrigNameCache
263 initOrigNames names = foldl extendOrigNameCache emptyModuleEnv names
268 %************************************************************************
270 Type variables and local Ids
272 %************************************************************************
275 tcIfaceLclId :: OccName -> IfL Id
277 = do { lcl <- getLclEnv
278 ; return (lookupOccEnv (if_id_env lcl) occ
280 pprPanic "tcIfaceLclId" (ppr occ)) }
282 extendIfaceIdEnv :: [Id] -> IfL a -> IfL a
283 extendIfaceIdEnv ids thing_inside
284 = do { env <- getLclEnv
285 ; let { id_env' = extendOccEnvList (if_id_env env) pairs
286 ; pairs = [(getOccName id, id) | id <- ids] }
287 ; setLclEnv (env { if_id_env = id_env' }) thing_inside }
290 tcIfaceTyVar :: OccName -> IfL TyVar
292 = do { lcl <- getLclEnv
293 ; return (lookupOccEnv (if_tv_env lcl) occ
295 pprPanic "tcIfaceTyVar" (ppr occ)) }
297 extendIfaceTyVarEnv :: [TyVar] -> IfL a -> IfL a
298 extendIfaceTyVarEnv tyvars thing_inside
299 = do { env <- getLclEnv
300 ; let { tv_env' = extendOccEnvList (if_tv_env env) pairs
301 ; pairs = [(getOccName tv, tv) | tv <- tyvars] }
302 ; setLclEnv (env { if_tv_env = tv_env' }) thing_inside }
306 %************************************************************************
308 Getting from RdrNames to Names
310 %************************************************************************
313 lookupIfaceTc :: IfaceTyCon -> IfL Name
314 lookupIfaceTc (IfaceTc ext) = lookupIfaceExt ext
315 lookupIfaceTc other_tc = return (ifaceTyConName other_tc)
317 lookupIfaceExt :: IfaceExtName -> IfL Name
318 lookupIfaceExt (ExtPkg mod occ) = lookupOrig mod occ
319 lookupIfaceExt (HomePkg mod occ _) = lookupOrig mod occ
320 lookupIfaceExt (LocalTop occ) = lookupIfaceTop occ
321 lookupIfaceExt (LocalTopSub occ _) = lookupIfaceTop occ
323 lookupIfaceTop :: OccName -> IfL Name
324 -- Look up a top-level name from the current Iface module
326 = do { env <- getLclEnv; lookupOrig (if_mod env) occ }
328 newIfaceName :: OccName -> IfL Name
330 = do { uniq <- newUnique
331 ; return (mkInternalName uniq occ noSrcLoc) }
333 newIfaceNames :: [OccName] -> IfL [Name]
335 = do { uniqs <- newUniqueSupply
336 ; return [ mkInternalName uniq occ noSrcLoc
337 | (occ,uniq) <- occs `zip` uniqsFromSupply uniqs] }