2 % (c) The University of Glasgow 2001-2006
5 module MkExternalCore (
9 #include "HsVersions.h"
11 import qualified ExternalCore as C
18 import PprExternalCore () -- Instances
34 emitExternalCore :: DynFlags -> CgGuts -> IO ()
35 emitExternalCore dflags cg_guts
36 | dopt Opt_EmitExternalCore dflags
37 = (do handle <- openFile corename WriteMode
38 hPutStrLn handle (show (mkExternalCore cg_guts))
40 `catch` (\_ -> pprPanic "Failed to open or write external core output file"
42 where corename = extCoreName dflags
47 -- Reinventing the Reader monad; whee.
48 newtype CoreM a = CoreM (CoreState -> (CoreState, a))
49 type CoreState = Module
50 instance Monad CoreM where
51 (CoreM m) >>= f = CoreM (\ s -> case m s of
54 return x = CoreM (\ s -> (s, x))
55 runCoreM :: CoreM a -> CoreState -> a
56 runCoreM (CoreM f) s = snd $ f s
57 ask :: CoreM CoreState
58 ask = CoreM (\ s -> (s,s))
60 mkExternalCore :: CgGuts -> C.Module
61 -- The ModGuts has been tidied, but the implicit bindings have
62 -- not been injected, so we have to add them manually here
63 -- We don't include the strange data-con *workers* because they are
64 -- implicit in the data type declaration itself
65 mkExternalCore (CgGuts {cg_module=this_mod, cg_tycons = tycons,
67 {- Note that modules can be mutually recursive, but even so, we
68 print out dependency information within each module. -}
69 = C.Module mname tdefs (runCoreM (mapM (make_vdef True) binds) this_mod)
71 mname = make_mid this_mod
72 tdefs = foldr collect_tdefs [] tycons
74 collect_tdefs :: TyCon -> [C.Tdef] -> [C.Tdef]
75 collect_tdefs tcon tdefs
76 | isAlgTyCon tcon = tdef: tdefs
78 tdef | isNewTyCon tcon =
80 (case newTyConCo_maybe tcon of
82 Nothing -> pprPanic ("MkExternalCore: newtype tcon\
83 should have a coercion: ") (ppr tcon))
84 (map make_tbind tyvars)
85 (make_ty (snd (newTyConRhs tcon)))
87 C.Data (qtc tcon) (map make_tbind tyvars)
88 (map make_cdef (tyConDataCons tcon))
89 tyvars = tyConTyVars tcon
91 collect_tdefs _ tdefs = tdefs
93 qtc :: TyCon -> C.Qual C.Tcon
94 qtc = make_con_qid . tyConName
97 make_cdef :: DataCon -> C.Cdef
98 make_cdef dcon = C.Constr dcon_name existentials tys
100 dcon_name = make_qid False False (dataConName dcon)
101 existentials = map make_tbind ex_tyvars
102 ex_tyvars = dataConExTyVars dcon
103 tys = map make_ty (dataConRepArgTys dcon)
105 make_tbind :: TyVar -> C.Tbind
106 make_tbind tv = (make_var_id (tyVarName tv), make_kind (tyVarKind tv))
108 make_vbind :: Var -> C.Vbind
109 make_vbind v = (make_var_id (Var.varName v), make_ty (varType v))
111 make_vdef :: Bool -> CoreBind -> CoreM C.Vdefg
112 make_vdef topLevel b =
114 NonRec v e -> f (v,e) >>= (return . C.Nonrec)
115 Rec ves -> mapM f ves >>= (return . C.Rec)
117 f :: (CoreBndr,CoreExpr) -> CoreM C.Vdef
119 localN <- isALocal vName
120 let local = not topLevel || localN
122 -- use local flag to determine where to add the module name
123 return (local, make_qid local True vName, make_ty (varType v),rhs)
124 where vName = Var.varName v
126 make_exp :: CoreExpr -> CoreM C.Exp
127 make_exp (Var v) = do
128 let vName = Var.varName v
129 isLocal <- isALocal vName
132 FCallId (CCall (CCallSpec (StaticTarget nm _) callconv _))
133 -> C.External (unpackFS nm) (showSDoc (ppr callconv)) (make_ty (varType v))
134 FCallId (CCall (CCallSpec DynamicTarget callconv _))
135 -> C.DynExternal (showSDoc (ppr callconv)) (make_ty (varType v))
136 -- Constructors are always exported, so make sure to declare them
137 -- with qualified names
138 DataConWorkId _ -> C.Var (make_var_qid False vName)
139 DataConWrapId _ -> C.Var (make_var_qid False vName)
140 _ -> C.Var (make_var_qid isLocal vName)
141 make_exp (Lit (MachLabel s _ _)) = return $ C.Label (unpackFS s)
142 make_exp (Lit l) = return $ C.Lit (make_lit l)
143 make_exp (App e (Type t)) = make_exp e >>= (\ b -> return $ C.Appt b (make_ty t))
144 make_exp (App e1 e2) = do
147 return $ C.App rator rand
148 make_exp (Lam v e) | isTyVar v = make_exp e >>= (\ b ->
149 return $ C.Lam (C.Tb (make_tbind v)) b)
150 make_exp (Lam v e) | otherwise = make_exp e >>= (\ b ->
151 return $ C.Lam (C.Vb (make_vbind v)) b)
152 make_exp (Cast e co) = make_exp e >>= (\ b -> return $ C.Cast b (make_ty co))
153 make_exp (Let b e) = do
154 vd <- make_vdef False b
156 return $ C.Let vd body
157 make_exp (Case e v ty alts) = do
159 newAlts <- mapM make_alt alts
160 return $ C.Case scrut (make_vbind v) (make_ty ty) newAlts
161 make_exp (Note (SCC _) e) = make_exp e >>= (return . C.Note "SCC") -- temporary
162 make_exp (Note (CoreNote s) e) = make_exp e >>= (return . C.Note s) -- hdaume: core annotations
163 make_exp _ = error "MkExternalCore died: make_exp"
165 make_alt :: CoreAlt -> CoreM C.Alt
166 make_alt (DataAlt dcon, vs, e) = do
168 return $ C.Acon (make_con_qid (dataConName dcon))
172 where (tbs,vbs) = span isTyVar vs
173 make_alt (LitAlt l,_,e) = make_exp e >>= (return . (C.Alit (make_lit l)))
174 make_alt (DEFAULT,[],e) = make_exp e >>= (return . C.Adefault)
175 -- This should never happen, as the DEFAULT alternative binds no variables,
176 -- but we might as well check for it:
177 make_alt a@(DEFAULT,_ ,_) = pprPanic ("MkExternalCore: make_alt: DEFAULT "
178 ++ "alternative had a non-empty var list") (ppr a)
181 make_lit :: Literal -> C.Lit
184 -- Note that we need to check whether the character is "big".
185 -- External Core only allows character literals up to '\xff'.
186 MachChar i | i <= chr 0xff -> C.Lchar i t
187 -- For a character bigger than 0xff, we represent it in ext-core
188 -- as an int lit with a char type.
189 MachChar i -> C.Lint (fromIntegral $ ord i) t
190 MachStr s -> C.Lstring (unpackFS s) t
191 MachNullAddr -> C.Lint 0 t
192 MachInt i -> C.Lint i t
193 MachInt64 i -> C.Lint i t
194 MachWord i -> C.Lint i t
195 MachWord64 i -> C.Lint i t
196 MachFloat r -> C.Lrational r t
197 MachDouble r -> C.Lrational r t
198 _ -> error "MkExternalCore died: make_lit"
200 t = make_ty (literalType l)
202 -- Expand type synonyms, then convert.
203 make_ty :: Type -> C.Ty -- Be sure to expand types recursively!
204 -- example: FilePath ~> String ~> [Char]
205 make_ty t | Just expanded <- tcView t = make_ty expanded
206 make_ty t = make_ty' t
208 -- note calls to make_ty so as to expand types recursively
209 make_ty' :: Type -> C.Ty
210 make_ty' (TyVarTy tv) = C.Tvar (make_var_id (tyVarName tv))
211 make_ty' (AppTy t1 t2) = C.Tapp (make_ty t1) (make_ty t2)
212 make_ty' (FunTy t1 t2) = make_ty (TyConApp funTyCon [t1,t2])
213 make_ty' (ForAllTy tv t) = C.Tforall (make_tbind tv) (make_ty t)
214 make_ty' (TyConApp tc ts) = make_tyConApp tc ts
216 -- Newtypes are treated just like any other type constructor; not expanded
217 -- Reason: predTypeRep does substitution and, while substitution deals
218 -- correctly with name capture, it's only correct if you see the uniques!
219 -- If you just see occurrence names, name capture may occur.
220 -- Example: newtype A a = A (forall b. b -> a)
221 -- test :: forall q b. q -> A b
222 -- test _ = undefined
223 -- Here the 'a' gets substituted by 'b', which is captured.
224 -- Another solution would be to expand newtypes before tidying; but that would
225 -- expose the representation in interface files, which definitely isn't right.
226 -- Maybe CoreTidy should know whether to expand newtypes or not?
228 make_ty' (PredTy p) = make_ty (predTypeRep p)
230 make_tyConApp :: TyCon -> [Type] -> C.Ty
231 make_tyConApp tc [t1, t2] | tc == transCoercionTyCon =
232 C.TransCoercion (make_ty t1) (make_ty t2)
233 make_tyConApp tc [t] | tc == symCoercionTyCon =
234 C.SymCoercion (make_ty t)
235 make_tyConApp tc [t1, t2] | tc == unsafeCoercionTyCon =
236 C.UnsafeCoercion (make_ty t1) (make_ty t2)
237 make_tyConApp tc [t] | tc == leftCoercionTyCon =
238 C.LeftCoercion (make_ty t)
239 make_tyConApp tc [t] | tc == rightCoercionTyCon =
240 C.RightCoercion (make_ty t)
241 make_tyConApp tc [t1, t2] | tc == instCoercionTyCon =
242 C.InstCoercion (make_ty t1) (make_ty t2)
243 -- this fails silently if we have an application
244 -- of a wired-in coercion tycon to the wrong number of args.
246 make_tyConApp tc ts =
247 foldl C.Tapp (C.Tcon (qtc tc))
251 make_kind :: Kind -> C.Kind
252 make_kind (PredTy p) | isEqPred p = C.Keq (make_ty t1) (make_ty t2)
253 where (t1, t2) = getEqPredTys p
254 make_kind (FunTy k1 k2) = C.Karrow (make_kind k1) (make_kind k2)
256 | isLiftedTypeKind k = C.Klifted
257 | isUnliftedTypeKind k = C.Kunlifted
258 | isOpenTypeKind k = C.Kopen
259 make_kind _ = error "MkExternalCore died: make_kind"
263 make_id :: Bool -> Name -> C.Id
264 -- include uniques for internal names in order to avoid name shadowing
265 make_id _is_var nm = ((occNameString . nameOccName) nm)
266 ++ (if isInternalName nm then (show . nameUnique) nm else "")
268 make_var_id :: Name -> C.Id
269 make_var_id = make_id True
271 -- It's important to encode the module name here, because in External Core,
272 -- base:GHC.Base => base:GHCziBase
273 -- We don't do this in pprExternalCore because we
274 -- *do* want to keep the package name (we don't want baseZCGHCziBase,
275 -- because that would just be ugly.)
277 -- We encode the package name as well.
278 make_mid :: Module -> C.Id
279 -- Super ugly code, but I can't find anything else that does quite what I
280 -- want (encodes the hierarchical module name without encoding the colon
281 -- that separates the package name from it.)
282 make_mid m = showSDoc $
283 (text $ zEncodeString $ packageIdString $ modulePackageId m)
285 <> (pprEncoded $ pprModuleName $ moduleName m)
286 where pprEncoded = pprCode CStyle
288 make_qid :: Bool -> Bool -> Name -> C.Qual C.Id
289 make_qid force_unqual is_var n = (mname,make_id is_var n)
291 case nameModule_maybe n of
292 Just m | not force_unqual -> make_mid m
295 make_var_qid :: Bool -> Name -> C.Qual C.Id
296 make_var_qid force_unqual = make_qid force_unqual True
298 make_con_qid :: Name -> C.Qual C.Id
299 make_con_qid = make_qid False False
302 isALocal :: Name -> CoreM Bool
305 return $ case nameModule_maybe vName of
306 -- Not sure whether isInternalName corresponds to "local"ness
307 -- in the External Core sense; need to re-read the spec.
308 Just m | m == modName -> isInternalName vName