Fix Trac #959: a long-standing bug in instantiating otherwise-unbound type variables
[ghc.git] / compiler / vectorise / VectUtils.hs
1 module VectUtils (
2 collectAnnTypeBinders, collectAnnTypeArgs, isAnnTypeArg,
3 collectAnnValBinders,
4 dataConTagZ, mkDataConTag, mkDataConTagLit,
5
6 newLocalVVar,
7
8 mkBuiltinCo, voidType, mkWrapType,
9 mkPADictType, mkPArrayType, mkPDataType, mkPReprType, mkPArray,
10
11 pdataReprTyCon, pdataReprDataCon, mkVScrut,
12 prDictOfType, prDFunOfTyCon,
13 paDictArgType, paDictOfType, paDFunType,
14 paMethod, wrapPR, replicatePD, emptyPD, packPD,
15 combinePD,
16 liftPD,
17 zipScalars, scalarClosure,
18 polyAbstract, polyApply, polyVApply,
19 hoistBinding, hoistExpr, hoistPolyVExpr, takeHoisted,
20 buildClosure, buildClosures,
21 mkClosureApp
22 ) where
23
24 import VectCore
25 import VectMonad
26
27 import MkCore ( mkCoreTup, mkCoreTupTy, mkWildCase )
28 import CoreSyn
29 import CoreUtils
30 import Coercion
31 import Type
32 import TypeRep
33 import TyCon
34 import DataCon
35 import Var
36 import MkId ( unwrapFamInstScrut )
37 import TysWiredIn
38 import BasicTypes ( Boxity(..) )
39 import Literal ( Literal, mkMachInt )
40
41 import Outputable
42 import FastString
43
44 import Control.Monad
45
46
47 collectAnnTypeArgs :: AnnExpr b ann -> (AnnExpr b ann, [Type])
48 collectAnnTypeArgs expr = go expr []
49 where
50 go (_, AnnApp f (_, AnnType ty)) tys = go f (ty : tys)
51 go e tys = (e, tys)
52
53 collectAnnTypeBinders :: AnnExpr Var ann -> ([Var], AnnExpr Var ann)
54 collectAnnTypeBinders expr = go [] expr
55 where
56 go bs (_, AnnLam b e) | isTyVar b = go (b:bs) e
57 go bs e = (reverse bs, e)
58
59 collectAnnValBinders :: AnnExpr Var ann -> ([Var], AnnExpr Var ann)
60 collectAnnValBinders expr = go [] expr
61 where
62 go bs (_, AnnLam b e) | isId b = go (b:bs) e
63 go bs e = (reverse bs, e)
64
65 isAnnTypeArg :: AnnExpr b ann -> Bool
66 isAnnTypeArg (_, AnnType _) = True
67 isAnnTypeArg _ = False
68
69 dataConTagZ :: DataCon -> Int
70 dataConTagZ con = dataConTag con - fIRST_TAG
71
72 mkDataConTagLit :: DataCon -> Literal
73 mkDataConTagLit = mkMachInt . toInteger . dataConTagZ
74
75 mkDataConTag :: DataCon -> CoreExpr
76 mkDataConTag = mkIntLitInt . dataConTagZ
77
78 splitPrimTyCon :: Type -> Maybe TyCon
79 splitPrimTyCon ty
80 | Just (tycon, []) <- splitTyConApp_maybe ty
81 , isPrimTyCon tycon
82 = Just tycon
83
84 | otherwise = Nothing
85
86 mkBuiltinTyConApp :: (Builtins -> TyCon) -> [Type] -> VM Type
87 mkBuiltinTyConApp get_tc tys
88 = do
89 tc <- builtin get_tc
90 return $ mkTyConApp tc tys
91
92 mkBuiltinTyConApps :: (Builtins -> TyCon) -> [Type] -> Type -> VM Type
93 mkBuiltinTyConApps get_tc tys ty
94 = do
95 tc <- builtin get_tc
96 return $ foldr (mk tc) ty tys
97 where
98 mk tc ty1 ty2 = mkTyConApp tc [ty1,ty2]
99
100 voidType :: VM Type
101 voidType = mkBuiltinTyConApp VectMonad.voidTyCon []
102
103 mkWrapType :: Type -> VM Type
104 mkWrapType ty = mkBuiltinTyConApp wrapTyCon [ty]
105
106 mkClosureTypes :: [Type] -> Type -> VM Type
107 mkClosureTypes = mkBuiltinTyConApps closureTyCon
108
109 mkPReprType :: Type -> VM Type
110 mkPReprType ty = mkBuiltinTyConApp preprTyCon [ty]
111
112 mkPADictType :: Type -> VM Type
113 mkPADictType ty = mkBuiltinTyConApp paTyCon [ty]
114
115 mkPArrayType :: Type -> VM Type
116 mkPArrayType ty
117 | Just tycon <- splitPrimTyCon ty
118 = do
119 r <- lookupPrimPArray tycon
120 case r of
121 Just arr -> return $ mkTyConApp arr []
122 Nothing -> cantVectorise "Primitive tycon not vectorised" (ppr tycon)
123 mkPArrayType ty = mkBuiltinTyConApp parrayTyCon [ty]
124
125 mkPDataType :: Type -> VM Type
126 mkPDataType ty = mkBuiltinTyConApp pdataTyCon [ty]
127
128 mkPArray :: Type -> CoreExpr -> CoreExpr -> VM CoreExpr
129 mkPArray ty len dat = do
130 tc <- builtin parrayTyCon
131 let [dc] = tyConDataCons tc
132 return $ mkConApp dc [Type ty, len, dat]
133
134 mkBuiltinCo :: (Builtins -> TyCon) -> VM Coercion
135 mkBuiltinCo get_tc
136 = do
137 tc <- builtin get_tc
138 return $ mkTyConApp tc []
139
140 pdataReprTyCon :: Type -> VM (TyCon, [Type])
141 pdataReprTyCon ty = builtin pdataTyCon >>= (`lookupFamInst` [ty])
142
143 pdataReprDataCon :: Type -> VM (DataCon, [Type])
144 pdataReprDataCon ty
145 = do
146 (tc, arg_tys) <- pdataReprTyCon ty
147 let [dc] = tyConDataCons tc
148 return (dc, arg_tys)
149
150 mkVScrut :: VExpr -> VM (CoreExpr, CoreExpr, TyCon, [Type])
151 mkVScrut (ve, le)
152 = do
153 (tc, arg_tys) <- pdataReprTyCon ty
154 return (ve, unwrapFamInstScrut tc arg_tys le, tc, arg_tys)
155 where
156 ty = exprType ve
157
158 prDFunOfTyCon :: TyCon -> VM CoreExpr
159 prDFunOfTyCon tycon
160 = liftM Var
161 . maybeCantVectoriseM "No PR dictionary for tycon" (ppr tycon)
162 $ lookupTyConPR tycon
163
164 paDictArgType :: TyVar -> VM (Maybe Type)
165 paDictArgType tv = go (TyVarTy tv) (tyVarKind tv)
166 where
167 go ty k | Just k' <- kindView k = go ty k'
168 go ty (FunTy k1 k2)
169 = do
170 tv <- newTyVar (fsLit "a") k1
171 mty1 <- go (TyVarTy tv) k1
172 case mty1 of
173 Just ty1 -> do
174 mty2 <- go (AppTy ty (TyVarTy tv)) k2
175 return $ fmap (ForAllTy tv . FunTy ty1) mty2
176 Nothing -> go ty k2
177
178 go ty k
179 | isLiftedTypeKind k
180 = liftM Just (mkPADictType ty)
181
182 go _ _ = return Nothing
183
184 paDictOfType :: Type -> VM CoreExpr
185 paDictOfType ty = paDictOfTyApp ty_fn ty_args
186 where
187 (ty_fn, ty_args) = splitAppTys ty
188
189 paDictOfTyApp :: Type -> [Type] -> VM CoreExpr
190 paDictOfTyApp ty_fn ty_args
191 | Just ty_fn' <- coreView ty_fn = paDictOfTyApp ty_fn' ty_args
192 paDictOfTyApp (TyVarTy tv) ty_args
193 = do
194 dfun <- maybeV (lookupTyVarPA tv)
195 paDFunApply dfun ty_args
196 paDictOfTyApp (TyConApp tc _) ty_args
197 = do
198 dfun <- maybeCantVectoriseM "No PA dictionary for tycon" (ppr tc)
199 $ lookupTyConPA tc
200 paDFunApply (Var dfun) ty_args
201 paDictOfTyApp ty _
202 = cantVectorise "Can't construct PA dictionary for type" (ppr ty)
203
204 paDFunType :: TyCon -> VM Type
205 paDFunType tc
206 = do
207 margs <- mapM paDictArgType tvs
208 res <- mkPADictType (mkTyConApp tc arg_tys)
209 return . mkForAllTys tvs
210 $ mkFunTys [arg | Just arg <- margs] res
211 where
212 tvs = tyConTyVars tc
213 arg_tys = mkTyVarTys tvs
214
215 paDFunApply :: CoreExpr -> [Type] -> VM CoreExpr
216 paDFunApply dfun tys
217 = do
218 dicts <- mapM paDictOfType tys
219 return $ mkApps (mkTyApps dfun tys) dicts
220
221 paMethod :: (Builtins -> Var) -> String -> Type -> VM CoreExpr
222 paMethod _ name ty
223 | Just tycon <- splitPrimTyCon ty
224 = liftM Var
225 . maybeCantVectoriseM "No PA method" (text name <+> text "for" <+> ppr tycon)
226 $ lookupPrimMethod tycon name
227
228 paMethod method _ ty
229 = do
230 fn <- builtin method
231 dict <- paDictOfType ty
232 return $ mkApps (Var fn) [Type ty, dict]
233
234 prDictOfType :: Type -> VM CoreExpr
235 prDictOfType ty = prDictOfTyApp ty_fn ty_args
236 where
237 (ty_fn, ty_args) = splitAppTys ty
238
239 prDictOfTyApp :: Type -> [Type] -> VM CoreExpr
240 prDictOfTyApp ty_fn ty_args
241 | Just ty_fn' <- coreView ty_fn = prDictOfTyApp ty_fn' ty_args
242 prDictOfTyApp (TyConApp tc _) ty_args
243 = do
244 dfun <- prDFunOfTyCon tc
245 prDFunApply dfun ty_args
246 prDictOfTyApp _ _ = noV
247
248 prDFunApply :: CoreExpr -> [Type] -> VM CoreExpr
249 prDFunApply dfun tys
250 = do
251 dicts <- mapM prDictOfType tys
252 return $ mkApps (mkTyApps dfun tys) dicts
253
254 wrapPR :: Type -> VM CoreExpr
255 wrapPR ty
256 = do
257 pa_dict <- paDictOfType ty
258 pr_dfun <- prDFunOfTyCon =<< builtin wrapTyCon
259 return $ mkApps pr_dfun [Type ty, pa_dict]
260
261 replicatePD :: CoreExpr -> CoreExpr -> VM CoreExpr
262 replicatePD len x = liftM (`mkApps` [len,x])
263 (paMethod replicatePDVar "replicatePD" (exprType x))
264
265 emptyPD :: Type -> VM CoreExpr
266 emptyPD = paMethod emptyPDVar "emptyPD"
267
268 packPD :: Type -> CoreExpr -> CoreExpr -> CoreExpr -> VM CoreExpr
269 packPD ty xs len sel = liftM (`mkApps` [xs, len, sel])
270 (paMethod packPDVar "packPD" ty)
271
272 combinePD :: Type -> CoreExpr -> CoreExpr -> [CoreExpr]
273 -> VM CoreExpr
274 combinePD ty len sel xs
275 = liftM (`mkApps` (len : sel : xs))
276 (paMethod (combinePDVar n) ("combine" ++ show n ++ "PD") ty)
277 where
278 n = length xs
279
280 liftPD :: CoreExpr -> VM CoreExpr
281 liftPD x
282 = do
283 lc <- builtin liftingContext
284 replicatePD (Var lc) x
285
286 zipScalars :: [Type] -> Type -> VM CoreExpr
287 zipScalars arg_tys res_ty
288 = do
289 scalar <- builtin scalarClass
290 (dfuns, _) <- mapAndUnzipM (\ty -> lookupInst scalar [ty]) ty_args
291 zipf <- builtin (scalarZip $ length arg_tys)
292 return $ Var zipf `mkTyApps` ty_args `mkApps` map Var dfuns
293 where
294 ty_args = arg_tys ++ [res_ty]
295
296 scalarClosure :: [Type] -> Type -> CoreExpr -> CoreExpr -> VM CoreExpr
297 scalarClosure arg_tys res_ty scalar_fun array_fun
298 = do
299 ctr <- builtin (closureCtrFun $ length arg_tys)
300 pas <- mapM paDictOfType (init arg_tys)
301 return $ Var ctr `mkTyApps` (arg_tys ++ [res_ty])
302 `mkApps` (pas ++ [scalar_fun, array_fun])
303
304 newLocalVVar :: FastString -> Type -> VM VVar
305 newLocalVVar fs vty
306 = do
307 lty <- mkPDataType vty
308 vv <- newLocalVar fs vty
309 lv <- newLocalVar fs lty
310 return (vv,lv)
311
312 polyAbstract :: [TyVar] -> ((CoreExpr -> CoreExpr) -> VM a) -> VM a
313 polyAbstract tvs p
314 = localV
315 $ do
316 mdicts <- mapM mk_dict_var tvs
317 zipWithM_ (\tv -> maybe (defLocalTyVar tv) (defLocalTyVarWithPA tv . Var)) tvs mdicts
318 p (mk_lams mdicts)
319 where
320 mk_dict_var tv = do
321 r <- paDictArgType tv
322 case r of
323 Just ty -> liftM Just (newLocalVar (fsLit "dPA") ty)
324 Nothing -> return Nothing
325
326 mk_lams mdicts = mkLams (tvs ++ [dict | Just dict <- mdicts])
327
328 polyApply :: CoreExpr -> [Type] -> VM CoreExpr
329 polyApply expr tys
330 = do
331 dicts <- mapM paDictOfType tys
332 return $ expr `mkTyApps` tys `mkApps` dicts
333
334 polyVApply :: VExpr -> [Type] -> VM VExpr
335 polyVApply expr tys
336 = do
337 dicts <- mapM paDictOfType tys
338 return $ mapVect (\e -> e `mkTyApps` tys `mkApps` dicts) expr
339
340 hoistBinding :: Var -> CoreExpr -> VM ()
341 hoistBinding v e = updGEnv $ \env ->
342 env { global_bindings = (v,e) : global_bindings env }
343
344 hoistExpr :: FastString -> CoreExpr -> VM Var
345 hoistExpr fs expr
346 = do
347 var <- newLocalVar fs (exprType expr)
348 hoistBinding var expr
349 return var
350
351 hoistVExpr :: VExpr -> VM VVar
352 hoistVExpr (ve, le)
353 = do
354 fs <- getBindName
355 vv <- hoistExpr ('v' `consFS` fs) ve
356 lv <- hoistExpr ('l' `consFS` fs) le
357 return (vv, lv)
358
359 hoistPolyVExpr :: [TyVar] -> VM VExpr -> VM VExpr
360 hoistPolyVExpr tvs p
361 = do
362 expr <- closedV . polyAbstract tvs $ \abstract ->
363 liftM (mapVect abstract) p
364 fn <- hoistVExpr expr
365 polyVApply (vVar fn) (mkTyVarTys tvs)
366
367 takeHoisted :: VM [(Var, CoreExpr)]
368 takeHoisted
369 = do
370 env <- readGEnv id
371 setGEnv $ env { global_bindings = [] }
372 return $ global_bindings env
373
374 {-
375 boxExpr :: Type -> VExpr -> VM VExpr
376 boxExpr ty (vexpr, lexpr)
377 | Just (tycon, []) <- splitTyConApp_maybe ty
378 , isUnLiftedTyCon tycon
379 = do
380 r <- lookupBoxedTyCon tycon
381 case r of
382 Just tycon' -> let [dc] = tyConDataCons tycon'
383 in
384 return (mkConApp dc [vexpr], lexpr)
385 Nothing -> return (vexpr, lexpr)
386 -}
387
388 mkClosure :: Type -> Type -> Type -> VExpr -> VExpr -> VM VExpr
389 mkClosure arg_ty res_ty env_ty (vfn,lfn) (venv,lenv)
390 = do
391 dict <- paDictOfType env_ty
392 mkv <- builtin closureVar
393 mkl <- builtin liftedClosureVar
394 return (Var mkv `mkTyApps` [arg_ty, res_ty, env_ty] `mkApps` [dict, vfn, lfn, venv],
395 Var mkl `mkTyApps` [arg_ty, res_ty, env_ty] `mkApps` [dict, vfn, lfn, lenv])
396
397 mkClosureApp :: Type -> Type -> VExpr -> VExpr -> VM VExpr
398 mkClosureApp arg_ty res_ty (vclo, lclo) (varg, larg)
399 = do
400 vapply <- builtin applyVar
401 lapply <- builtin liftedApplyVar
402 lc <- builtin liftingContext
403 return (Var vapply `mkTyApps` [arg_ty, res_ty] `mkApps` [vclo, varg],
404 Var lapply `mkTyApps` [arg_ty, res_ty] `mkApps` [Var lc, lclo, larg])
405
406 buildClosures :: [TyVar] -> [VVar] -> [Type] -> Type -> VM VExpr -> VM VExpr
407 buildClosures _ _ [] _ mk_body
408 = mk_body
409 buildClosures tvs vars [arg_ty] res_ty mk_body
410 = liftM vInlineMe (buildClosure tvs vars arg_ty res_ty mk_body)
411 buildClosures tvs vars (arg_ty : arg_tys) res_ty mk_body
412 = do
413 res_ty' <- mkClosureTypes arg_tys res_ty
414 arg <- newLocalVVar (fsLit "x") arg_ty
415 liftM vInlineMe
416 . buildClosure tvs vars arg_ty res_ty'
417 . hoistPolyVExpr tvs
418 $ do
419 lc <- builtin liftingContext
420 clo <- buildClosures tvs (vars ++ [arg]) arg_tys res_ty mk_body
421 return $ vLams lc (vars ++ [arg]) clo
422
423 -- (clo <x1,...,xn> <f,f^>, aclo (Arr lc xs1 ... xsn) <f,f^>)
424 -- where
425 -- f = \env v -> case env of <x1,...,xn> -> e x1 ... xn v
426 -- f^ = \env v -> case env of Arr l xs1 ... xsn -> e^ l x1 ... xn v
427 --
428 buildClosure :: [TyVar] -> [VVar] -> Type -> Type -> VM VExpr -> VM VExpr
429 buildClosure tvs vars arg_ty res_ty mk_body
430 = do
431 (env_ty, env, bind) <- buildEnv vars
432 env_bndr <- newLocalVVar (fsLit "env") env_ty
433 arg_bndr <- newLocalVVar (fsLit "arg") arg_ty
434
435 fn <- hoistPolyVExpr tvs
436 $ do
437 lc <- builtin liftingContext
438 body <- mk_body
439 return . vInlineMe
440 . vLams lc [env_bndr, arg_bndr]
441 $ bind (vVar env_bndr)
442 (vVarApps lc body (vars ++ [arg_bndr]))
443
444 mkClosure arg_ty res_ty env_ty fn env
445
446 buildEnv :: [VVar] -> VM (Type, VExpr, VExpr -> VExpr -> VExpr)
447 buildEnv [] = do
448 ty <- voidType
449 void <- builtin voidVar
450 pvoid <- builtin pvoidVar
451 return (ty, vVar (void, pvoid), \_ body -> body)
452
453 buildEnv [v] = return (vVarType v, vVar v,
454 \env body -> vLet (vNonRec v env) body)
455
456 buildEnv vs
457 = do
458
459 (lenv_tc, lenv_tyargs) <- pdataReprTyCon ty
460
461 let venv_con = tupleCon Boxed (length vs)
462 [lenv_con] = tyConDataCons lenv_tc
463
464 venv = mkCoreTup (map Var vvs)
465 lenv = Var (dataConWrapId lenv_con)
466 `mkTyApps` lenv_tyargs
467 `mkApps` map Var lvs
468
469 vbind env body = mkWildCase env ty (exprType body)
470 [(DataAlt venv_con, vvs, body)]
471
472 lbind env body =
473 let scrut = unwrapFamInstScrut lenv_tc lenv_tyargs env
474 in
475 mkWildCase scrut (exprType scrut) (exprType body)
476 [(DataAlt lenv_con, lvs, body)]
477
478 bind (venv, lenv) (vbody, lbody) = (vbind venv vbody,
479 lbind lenv lbody)
480
481 return (ty, (venv, lenv), bind)
482 where
483 (vvs, lvs) = unzip vs
484 tys = map vVarType vs
485 ty = mkCoreTupTy tys
486