X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2FcoreSyn%2FCoreLint.lhs;h=031fd613ccc990fd1fba9e50842290d6ecebd1e3;hp=274762515506946e0c7aa2ab8278d17520a076f8;hb=c8c2f6bb7d79a2a6aeaa3233363fdf0bbbfad205;hpb=c4ea6c7d0063be9323268ebffe6b9d0d6625b2e3 diff --git a/compiler/coreSyn/CoreLint.lhs b/compiler/coreSyn/CoreLint.lhs index 2747625..031fd61 100644 --- a/compiler/coreSyn/CoreLint.lhs +++ b/compiler/coreSyn/CoreLint.lhs @@ -11,10 +11,11 @@ module CoreLint ( lintCoreBindings, lintUnfolding ) where #include "HsVersions.h" -import NewDemand +import Demand import CoreSyn import CoreFVs import CoreUtils +import Pair import Bag import Literal import DataCon @@ -27,18 +28,22 @@ import Id import PprCore import ErrUtils import SrcLoc +import Kind import Type +import TypeRep import Coercion import TyCon +import Class import BasicTypes import StaticFlags import ListSetOps -import DynFlags +import PrelNames import Outputable import FastString import Util import Control.Monad import Data.Maybe +import Data.Traversable (traverse) \end{code} %************************************************************************ @@ -81,7 +86,7 @@ That is, use a type let. See Note [Type let] in CoreSyn. However, when linting we need to remember that a=Int, else we might reject a correct program. So we carry a type substitution (in this example [a -> Int]) and apply this substitution before comparing types. The functin - lintTy :: Type -> LintM Type + lintInTy :: Type -> LintM Type returns a substituted type; that's the only reason it returns anything. When we encounter a binder (like x::a) we must apply the substitution @@ -93,45 +98,36 @@ find an occurence of an Id, we fetch it from the in-scope set. \begin{code} -lintCoreBindings :: DynFlags -> String -> [CoreBind] -> IO () - -lintCoreBindings dflags _whoDunnit _binds - | not (dopt Opt_DoCoreLinting dflags) - = return () - -lintCoreBindings dflags whoDunnit binds - | isEmptyBag errs - = do { showPass dflags ("Core Linted result of " ++ whoDunnit) - ; unless (isEmptyBag warns || opt_NoDebugOutput) $ printDump $ - (banner "warnings" $$ displayMessageBag warns) - ; return () } - - | otherwise - = do { printDump (vcat [ banner "errors", displayMessageBag errs - , ptext (sLit "*** Offending Program ***") - , pprCoreBindings binds - , ptext (sLit "*** End of Offense ***") ]) - - ; ghcExit dflags 1 } - where - (warns, errs) = initL (lint_binds binds) - +lintCoreBindings :: [CoreBind] -> (Bag Message, Bag Message) +-- Returns (warnings, errors) +lintCoreBindings binds + = initL $ + addLoc TopLevelBindings $ + addInScopeVars binders $ -- Put all the top-level binders in scope at the start -- This is because transformation rules can bring something -- into use 'unexpectedly' - lint_binds binds = addLoc TopLevelBindings $ - addInScopeVars (bindersOfBinds binds) $ - mapM lint_bind binds + do { checkL (null dups) (dupVars dups) + ; checkL (null ext_dups) (dupExtVars ext_dups) + ; mapM lint_bind binds } + where + binders = bindersOfBinds binds + (_, dups) = removeDups compare binders + + -- dups_ext checks for names with different uniques + -- but but the same External name M.n. We don't + -- allow this at top level: + -- M.n{r3} = ... + -- M.n{r29} = ... + -- becuase they both get the same linker symbol + ext_dups = snd (removeDups ord_ext (map Var.varName binders)) + ord_ext n1 n2 | Just m1 <- nameModule_maybe n1 + , Just m2 <- nameModule_maybe n2 + = compare (m1, nameOccName n1) (m2, nameOccName n2) + | otherwise = LT lint_bind (Rec prs) = mapM_ (lintSingleBinding TopLevel Recursive) prs lint_bind (NonRec bndr rhs) = lintSingleBinding TopLevel NonRecursive (bndr,rhs) - - banner string = ptext (sLit "*** Core Lint") <+> text string - <+> ptext (sLit ": in result of") <+> text whoDunnit - <+> ptext (sLit "***") - -displayMessageBag :: Bag Message -> SDoc -displayMessageBag msgs = vcat (punctuate blankLine (bagToList msgs)) \end{code} %************************************************************************ @@ -151,7 +147,7 @@ lintUnfolding :: SrcLoc lintUnfolding locn vars expr | isEmptyBag errs = Nothing - | otherwise = Just (displayMessageBag errs) + | otherwise = Just (pprMessageBag errs) where (_warns, errs) = initL (addLoc (ImportedUnfolding locn) $ addInScopeVars vars $ @@ -173,7 +169,7 @@ lintSingleBinding top_lvl_flag rec_flag (binder,rhs) -- Check the rhs do { ty <- lintCoreExpr rhs ; lintBinder binder -- Check match to RHS type - ; binder_ty <- applySubst binder_ty + ; binder_ty <- applySubstTy binder_ty ; checkTys binder_ty ty (mkRhsMsg binder ty) -- Check (not isUnLiftedType) (also checks for bogus unboxed tuples) ; checkL (not (isUnLiftedType binder_ty) @@ -186,8 +182,9 @@ lintSingleBinding top_lvl_flag rec_flag (binder,rhs) -- Check whether binder's specialisations contain any out-of-scope variables ; mapM_ (checkBndrIdInScope binder) bndr_vars - ; when (isLoopBreaker (idOccInfo binder) && isInlinePragma (idInlinePragma binder)) - (addWarnL (ptext (sLit "INLINE binder is loop breaker:") <+> ppr binder)) + ; when (isNonRuleLoopBreaker (idOccInfo binder) && isInlinePragma (idInlinePragma binder)) + (addWarnL (ptext (sLit "INLINE binder is (non-rule) loop breaker:") <+> ppr binder)) + -- Only non-rule loop breakers inhibit inlining -- Check whether arity and demand type are consistent (only if demand analysis -- already happened) @@ -200,7 +197,7 @@ lintSingleBinding top_lvl_flag rec_flag (binder,rhs) -- the unfolding is a SimplifiableCoreExpr. Give up for now. where binder_ty = idType binder - maybeDmdTy = idNewStrictness_maybe binder + maybeDmdTy = idStrictness_maybe binder bndr_vars = varSetElems (idFreeVars binder) lintBinder var | isId var = lintIdBndr var $ \_ -> (return ()) | otherwise = return () @@ -213,8 +210,15 @@ lintSingleBinding top_lvl_flag rec_flag (binder,rhs) %************************************************************************ \begin{code} -type InType = Type -- Substitution not yet applied -type OutType = Type -- Substitution has been applied to this +type InType = Type -- Substitution not yet applied +type InCoercion = Coercion +type InVar = Var +type InTyVar = TyVar + +type OutType = Type -- Substitution has been applied to this +type OutCoercion = Coercion +type OutVar = Var +type OutTyVar = TyVar lintCoreExpr :: CoreExpr -> LintM OutType -- The returned type has the substitution from the monad @@ -227,25 +231,20 @@ lintCoreExpr (Var var) = do { checkL (not (var == oneTupleDataConId)) (ptext (sLit "Illegal one-tuple")) - ; checkDeadIdOcc var + ; checkL (isId var && not (isCoVar var)) + (ptext (sLit "Non term variable") <+> ppr var) + + ; checkDeadIdOcc var ; var' <- lookupIdInScope var - ; return (idType var') - } + ; return (idType var') } lintCoreExpr (Lit lit) = return (literalType lit) ---lintCoreExpr (Note (Coerce to_ty from_ty) expr) --- = do { expr_ty <- lintCoreExpr expr --- ; to_ty <- lintTy to_ty --- ; from_ty <- lintTy from_ty --- ; checkTys from_ty expr_ty (mkCoerceErr from_ty expr_ty) --- ; return to_ty } - lintCoreExpr (Cast expr co) = do { expr_ty <- lintCoreExpr expr - ; co' <- lintTy co - ; let (from_ty, to_ty) = coercionKind co' + ; co' <- applySubstCo co + ; (from_ty, to_ty) <- lintCoercion co' ; checkTys from_ty expr_ty (mkCastErr from_ty expr_ty) ; return to_ty } @@ -253,30 +252,34 @@ lintCoreExpr (Note _ expr) = lintCoreExpr expr lintCoreExpr (Let (NonRec tv (Type ty)) body) - = -- See Note [Type let] in CoreSyn - do { checkL (isTyVar tv) (mkKindErrMsg tv ty) -- Not quite accurate - ; ty' <- lintTy ty - ; kind' <- lintTy (tyVarKind tv) - ; let tv' = setTyVarKind tv kind' - ; checkKinds tv' ty' + | isTyVar tv + = -- See Note [Linting type lets] + do { ty' <- addLoc (RhsOf tv) $ lintInTy ty + ; lintTyBndr tv $ \ tv' -> + addLoc (BodyOfLetRec [tv]) $ + extendSubstL tv' ty' $ do + { checkTyKind tv' ty' -- Now extend the substitution so we -- take advantage of it in the body - ; addLoc (BodyOfLetRec [tv]) $ - addInScopeVars [tv'] $ - extendSubstL tv' ty' $ - lintCoreExpr body } + ; lintCoreExpr body } } lintCoreExpr (Let (NonRec bndr rhs) body) + | isId bndr = do { lintSingleBinding NotTopLevel NonRecursive (bndr,rhs) - ; addLoc (BodyOfLetRec [bndr]) + ; addLoc (BodyOfLetRec [bndr]) (lintAndScopeId bndr $ \_ -> (lintCoreExpr body)) } + | otherwise + = failWithL (mkLetErr bndr rhs) -- Not quite accurate + lintCoreExpr (Let (Rec pairs) body) = lintAndScopeIds bndrs $ \_ -> - do { mapM_ (lintSingleBinding NotTopLevel Recursive) pairs + do { checkL (null dups) (dupVars dups) + ; mapM_ (lintSingleBinding NotTopLevel Recursive) pairs ; addLoc (BodyOfLetRec bndrs) (lintCoreExpr body) } where bndrs = map fst pairs + (_, dups) = removeDups compare bndrs lintCoreExpr e@(App fun arg) = do { fun_ty <- lintCoreExpr fun @@ -285,27 +288,28 @@ lintCoreExpr e@(App fun arg) lintCoreExpr (Lam var expr) = addLoc (LambdaBodyOf var) $ - lintBinders [var] $ \[var'] -> - do { body_ty <- lintCoreExpr expr + lintBinders [var] $ \ vars' -> + do { let [var'] = vars' + ; body_ty <- lintCoreExpr expr ; if isId var' then return (mkFunTy (idType var') body_ty) else return (mkForAllTy var' body_ty) } - -- The applySubst is needed to apply the subst to var + -- The applySubstTy is needed to apply the subst to var lintCoreExpr e@(Case scrut var alt_ty alts) = -- Check the scrutinee do { scrut_ty <- lintCoreExpr scrut - ; alt_ty <- lintTy alt_ty - ; var_ty <- lintTy (idType var) + ; alt_ty <- lintInTy alt_ty + ; var_ty <- lintInTy (idType var) ; let mb_tc_app = splitTyConApp_maybe (idType var) ; case mb_tc_app of Just (tycon, _) | debugIsOn && isAlgTyCon tycon && - not (isOpenTyCon tycon) && + not (isFamilyTyCon tycon || isAbstractTyCon tycon) && null (tyConDataCons tycon) -> pprTrace "Lint warning: case binder's type has no constructors" (ppr var <+> ppr (idType var)) -- This can legitimately happen for type families @@ -330,8 +334,13 @@ lintCoreExpr e@(Case scrut var alt_ty alts) = pass_var f = f var lintCoreExpr (Type ty) - = do { ty' <- lintTy ty + = do { ty' <- lintInTy ty ; return (typeKind ty') } + +lintCoreExpr (Coercion co) + = do { co' <- lintInCo co + ; let Pair ty1 ty2 = coercionKind co' + ; return (mkPredTy $ EqPred ty1 ty2) } \end{code} %************************************************************************ @@ -344,60 +353,83 @@ The basic version of these functions checks that the argument is a subtype of the required type, as one would expect. \begin{code} -lintCoreArgs :: OutType -> [CoreArg] -> LintM OutType -lintCoreArg :: OutType -> CoreArg -> LintM OutType --- First argument has already had substitution applied to it -\end{code} +lintCoreArg :: OutType -> CoreArg -> LintM OutType +lintCoreArg fun_ty (Type arg_ty) + = do { arg_ty' <- applySubstTy arg_ty + ; lintTyApp fun_ty arg_ty' } + +lintCoreArg fun_ty arg + = do { arg_ty <- lintCoreExpr arg + ; lintValApp arg fun_ty arg_ty } + +----------------- +lintAltBinders :: OutType -- Scrutinee type + -> OutType -- Constructor type + -> [OutVar] -- Binders + -> LintM () +lintAltBinders scrut_ty con_ty [] + = checkTys con_ty scrut_ty (mkBadPatMsg con_ty scrut_ty) +lintAltBinders scrut_ty con_ty (bndr:bndrs) + | isTyVar bndr + = do { con_ty' <- lintTyApp con_ty (mkTyVarTy bndr) + ; lintAltBinders scrut_ty con_ty' bndrs } + | otherwise + = do { con_ty' <- lintValApp (Var bndr) con_ty (idType bndr) + ; lintAltBinders scrut_ty con_ty' bndrs } -\begin{code} -lintCoreArgs ty [] = return ty -lintCoreArgs ty (a : args) = - do { res <- lintCoreArg ty a - ; lintCoreArgs res args } - -lintCoreArg fun_ty (Type arg_ty) = - do { arg_ty <- lintTy arg_ty - ; lintTyApp fun_ty arg_ty } - -lintCoreArg fun_ty arg = - -- Make sure function type matches argument - do { arg_ty <- lintCoreExpr arg - ; let err1 = mkAppMsg fun_ty arg_ty arg - err2 = mkNonFunAppMsg fun_ty arg_ty arg - ; case splitFunTy_maybe fun_ty of - Just (arg,res) -> - do { checkTys arg arg_ty err1 - ; return res } - _ -> failWithL err2 } +----------------- +lintTyApp :: OutType -> OutType -> LintM OutType +lintTyApp fun_ty arg_ty + | Just (tyvar,body_ty) <- splitForAllTy_maybe fun_ty + , isTyVar tyvar + = do { checkTyKind tyvar arg_ty + ; return (substTyWith [tyvar] [arg_ty] body_ty) } + + | otherwise + = failWithL (mkTyAppMsg fun_ty arg_ty) + +----------------- +lintValApp :: CoreExpr -> OutType -> OutType -> LintM OutType +lintValApp arg fun_ty arg_ty + | Just (arg,res) <- splitFunTy_maybe fun_ty + = do { checkTys arg arg_ty err1 + ; return res } + | otherwise + = failWithL err2 + where + err1 = mkAppMsg fun_ty arg_ty arg + err2 = mkNonFunAppMsg fun_ty arg_ty arg \end{code} \begin{code} +checkTyKind :: OutTyVar -> OutType -> LintM () -- Both args have had substitution applied -lintTyApp :: OutType -> OutType -> LintM OutType -lintTyApp ty arg_ty - = case splitForAllTy_maybe ty of - Nothing -> failWithL (mkTyAppMsg ty arg_ty) - - Just (tyvar,body) - -> do { checkL (isTyVar tyvar) (mkTyAppMsg ty arg_ty) - ; checkKinds tyvar arg_ty - ; return (substTyWith [tyvar] [arg_ty] body) } - -checkKinds :: Var -> Type -> LintM () -checkKinds tyvar arg_ty +checkTyKind tyvar arg_ty -- Arg type might be boxed for a function with an uncommitted -- tyvar; notably this is used so that we can give -- error :: forall a:*. String -> a -- and then apply it to both boxed and unboxed types. - | isCoVar tyvar = unless (s1 `coreEqType` s2 && t1 `coreEqType` t2) - (addErrL (mkCoAppErrMsg tyvar arg_ty)) - | otherwise = unless (arg_kind `isSubKind` tyvar_kind) - (addErrL (mkKindErrMsg tyvar arg_ty)) + = do { arg_kind <- lintType arg_ty + ; unless (arg_kind `isSubKind` tyvar_kind) + (addErrL (mkKindErrMsg tyvar arg_ty)) } where tyvar_kind = tyVarKind tyvar - arg_kind = typeKind arg_ty - (s1,t1) = coVarKind tyvar - (s2,t2) = coercionKind arg_ty + +-- Check that the kinds of a type variable and a coercion match, that +-- is, if tv :: k then co :: t1 ~ t2 where t1 :: k and t2 :: k. +checkTyCoKind :: TyVar -> OutCoercion -> LintM (OutType, OutType) +checkTyCoKind tv co + = do { (t1,t2) <- lintCoercion co + ; k1 <- lintType t1 + ; k2 <- lintType t2 + ; unless ((k1 `isSubKind` tyvar_kind) && (k2 `isSubKind` tyvar_kind)) + (addErrL (mkTyCoAppErrMsg tv co)) + ; return (t1,t2) } + where + tyvar_kind = tyVarKind tv + +checkTyCoKinds :: [TyVar] -> [OutCoercion] -> LintM [(OutType, OutType)] +checkTyCoKinds = zipWithM checkTyCoKind checkDeadIdOcc :: Id -> LintM () -- Occurrences of an Id should never be dead.... @@ -474,7 +506,8 @@ lintCoreAlt scrut_ty alt_ty (LitAlt lit, args, rhs) = lit_ty = literalType lit lintCoreAlt scrut_ty alt_ty alt@(DataAlt con, args, rhs) - | isNewTyCon (dataConTyCon con) = addErrL (mkNewTyDataConAltMsg scrut_ty alt) + | isNewTyCon (dataConTyCon con) + = addErrL (mkNewTyDataConAltMsg scrut_ty alt) | Just (tycon, tycon_arg_tys) <- splitTyConApp_maybe scrut_ty = addLoc (CaseAlt alt) $ do { -- First instantiate the universally quantified @@ -484,19 +517,8 @@ lintCoreAlt scrut_ty alt_ty alt@(DataAlt con, args, rhs) ; let con_payload_ty = applyTys (dataConRepType con) tycon_arg_tys -- And now bring the new binders into scope - ; lintBinders args $ \ args -> do - { addLoc (CasePat alt) $ do - { -- Check the pattern - -- Scrutinee type must be a tycon applicn; checked by caller - -- This code is remarkably compact considering what it does! - -- NB: args must be in scope here so that the lintCoreArgs - -- line works. - -- NB: relies on existential type args coming *after* - -- ordinary type args - ; con_result_ty <- lintCoreArgs con_payload_ty (varsToCoreExprs args) - ; checkTys con_result_ty scrut_ty (mkBadPatMsg con_result_ty scrut_ty) - } - -- Check the RHS + ; lintBinders args $ \ args' -> do + { addLoc (CasePat alt) (lintAltBinders scrut_ty con_payload_ty args') ; checkAltExpr rhs alt_ty } } | otherwise -- Scrut-ty is wrong shape @@ -522,51 +544,230 @@ lintBinders (var:vars) linterF = lintBinder var $ \var' -> lintBinder :: Var -> (Var -> LintM a) -> LintM a lintBinder var linterF - | isTyVar var = lint_ty_bndr - | otherwise = lintIdBndr var linterF - where - lint_ty_bndr = do { _ <- lintTy (tyVarKind var) - ; subst <- getTvSubst - ; let (subst', tv') = substTyVarBndr subst var - ; updateTvSubst subst' (linterF tv') } + | isId var = lintIdBndr var linterF + | otherwise = lintTyBndr var linterF + +lintTyBndr :: InTyVar -> (OutTyVar -> LintM a) -> LintM a +lintTyBndr tv thing_inside + = do { subst <- getTvSubst + ; let (subst', tv') = Type.substTyVarBndr subst tv + ; lintTyBndrKind tv' + ; updateTvSubst subst' (thing_inside tv') } -lintIdBndr :: Var -> (Var -> LintM a) -> LintM a +lintIdBndr :: Id -> (Id -> LintM a) -> LintM a -- Do substitution on the type of a binder and add the var with this -- new type to the in-scope set of the second argument -- ToDo: lint its rules + lintIdBndr id linterF = do { checkL (not (isUnboxedTupleType (idType id))) (mkUnboxedTupleMsg id) -- No variable can be bound to an unboxed tuple. - ; lintAndScopeId id $ \id' -> linterF id' - } + ; lintAndScopeId id $ \id' -> linterF id' } lintAndScopeIds :: [Var] -> ([Var] -> LintM a) -> LintM a lintAndScopeIds ids linterF = go ids where go [] = linterF [] - go (id:ids) = do { lintAndScopeId id $ \id -> - lintAndScopeIds ids $ \ids -> - linterF (id:ids) } + go (id:ids) = lintAndScopeId id $ \id -> + lintAndScopeIds ids $ \ids -> + linterF (id:ids) -lintAndScopeId :: Var -> (Var -> LintM a) -> LintM a +lintAndScopeId :: InVar -> (OutVar -> LintM a) -> LintM a lintAndScopeId id linterF - = do { ty <- lintTy (idType id) + = do { ty <- lintInTy (idType id) ; let id' = setIdType id ty - ; addInScopeVars [id'] $ (linterF id') - } + ; addInScopeVar id' $ (linterF id') } +\end{code} + -lintTy :: InType -> LintM OutType +%************************************************************************ +%* * +\subsection[lint-monad]{The Lint monad} +%* * +%************************************************************************ + +\begin{code} +lintInTy :: InType -> LintM OutType -- Check the type, and apply the substitution to it -- See Note [Linting type lets] -- ToDo: check the kind structure of the type -lintTy ty - = do { ty' <- applySubst ty - ; mapM_ checkTyVarInScope (varSetElems (tyVarsOfType ty')) +lintInTy ty + = addLoc (InType ty) $ + do { ty' <- applySubstTy ty + ; _ <- lintType ty' ; return ty' } -\end{code} +lintInCo :: InCoercion -> LintM OutCoercion +-- Check the coercion, and apply the substitution to it +-- See Note [Linting type lets] +lintInCo co + = addLoc (InCo co) $ + do { co' <- applySubstCo co + ; _ <- lintCoercion co' + ; return co' } + +------------------- +lintKind :: Kind -> LintM () +-- Check well-formedness of kinds: *, *->*, etc +lintKind (TyConApp tc []) + | getUnique tc `elem` kindKeys + = return () +lintKind (FunTy k1 k2) + = lintKind k1 >> lintKind k2 +lintKind kind + = addErrL (hang (ptext (sLit "Malformed kind:")) 2 (quotes (ppr kind))) + +------------------- +lintTyBndrKind :: OutTyVar -> LintM () +lintTyBndrKind tv = lintKind (tyVarKind tv) + +------------------- +lintCoercion :: OutCoercion -> LintM (OutType, OutType) +-- Check the kind of a coercion term, returning the kind +lintCoercion (Refl ty) + = do { ty' <- lintInTy ty + ; return (ty', ty') } + +lintCoercion co@(TyConAppCo tc cos) + = do { (ss,ts) <- mapAndUnzipM lintCoercion cos + ; check_co_app co (tyConKind tc) ss + ; return (mkTyConApp tc ss, mkTyConApp tc ts) } + +lintCoercion co@(AppCo co1 co2) + = do { (s1,t1) <- lintCoercion co1 + ; (s2,t2) <- lintCoercion co2 + ; check_co_app co (typeKind s1) [s2] + ; return (mkAppTy s1 s2, mkAppTy t1 t2) } + +lintCoercion (ForAllCo v co) + = do { lintKind (tyVarKind v) + ; (s,t) <- addInScopeVar v (lintCoercion co) + ; return (ForAllTy v s, ForAllTy v t) } + +lintCoercion (CoVarCo cv) + = do { checkTyCoVarInScope cv + ; return (coVarKind cv) } + +lintCoercion (AxiomInstCo (CoAxiom { co_ax_tvs = tvs + , co_ax_lhs = lhs + , co_ax_rhs = rhs }) + cos) + = do { (tys1, tys2) <- liftM unzip (checkTyCoKinds tvs cos) + ; return (substTyWith tvs tys1 lhs, + substTyWith tvs tys2 rhs) } + +lintCoercion (UnsafeCo ty1 ty2) + = do { ty1' <- lintInTy ty1 + ; ty2' <- lintInTy ty2 + ; return (ty1', ty2') } + +lintCoercion (SymCo co) + = do { (ty1, ty2) <- lintCoercion co + ; return (ty2, ty1) } + +lintCoercion co@(TransCo co1 co2) + = do { (ty1a, ty1b) <- lintCoercion co1 + ; (ty2a, ty2b) <- lintCoercion co2 + ; checkL (ty1b `eqType` ty2a) + (hang (ptext (sLit "Trans coercion mis-match:") <+> ppr co) + 2 (vcat [ppr ty1a, ppr ty1b, ppr ty2a, ppr ty2b])) + ; return (ty1a, ty2b) } + +lintCoercion the_co@(NthCo d co) + = do { (s,t) <- lintCoercion co + ; sn <- checkTcApp the_co d s + ; tn <- checkTcApp the_co d t + ; return (sn, tn) } + +lintCoercion (InstCo co arg_ty) + = do { co_tys <- lintCoercion co + ; arg_kind <- lintType arg_ty + ; case splitForAllTy_maybe `traverse` toPair co_tys of + Just (Pair (tv1,ty1) (tv2,ty2)) + | arg_kind `isSubKind` tyVarKind tv1 + -> return (substTyWith [tv1] [arg_ty] ty1, + substTyWith [tv2] [arg_ty] ty2) + | otherwise + -> failWithL (ptext (sLit "Kind mis-match in inst coercion")) + Nothing -> failWithL (ptext (sLit "Bad argument of inst")) } + +---------- +checkTcApp :: Coercion -> Int -> Type -> LintM Type +checkTcApp co n ty + | Just (_, tys) <- splitTyConApp_maybe ty + , n < length tys + = return (tys !! n) + | otherwise + = failWithL (hang (ptext (sLit "Bad getNth:") <+> ppr co) + 2 (ptext (sLit "Offending type:") <+> ppr ty)) + +------------------- +lintType :: OutType -> LintM Kind +lintType (TyVarTy tv) + = do { checkTyCoVarInScope tv + ; return (tyVarKind tv) } + +lintType ty@(AppTy t1 t2) + = do { k1 <- lintType t1 + ; lint_ty_app ty k1 [t2] } + +lintType ty@(FunTy t1 t2) + = lint_ty_app ty (tyConKind funTyCon) [t1,t2] + +lintType ty@(TyConApp tc tys) + | tyConHasKind tc + = lint_ty_app ty (tyConKind tc) tys + | otherwise + = failWithL (hang (ptext (sLit "Malformed type:")) 2 (ppr ty)) + +lintType (ForAllTy tv ty) + = do { lintTyBndrKind tv + ; addInScopeVar tv (lintType ty) } + +lintType ty@(PredTy (ClassP cls tys)) + = lint_ty_app ty (tyConKind (classTyCon cls)) tys + +lintType (PredTy (IParam _ p_ty)) + = lintType p_ty + +lintType ty@(PredTy (EqPred t1 t2)) + = do { k1 <- lintType t1 + ; k2 <- lintType t2 + ; unless (k1 `eqKind` k2) + (addErrL (sep [ ptext (sLit "Kind mis-match in equality predicate:") + , nest 2 (ppr ty) ])) + ; return unliftedTypeKind } + +---------------- +lint_ty_app :: Type -> Kind -> [OutType] -> LintM Kind +lint_ty_app ty k tys + = do { ks <- mapM lintType tys + ; lint_kind_app (ptext (sLit "type") <+> quotes (ppr ty)) k ks } + +---------------- +check_co_app :: Coercion -> Kind -> [OutType] -> LintM () +check_co_app ty k tys + = do { _ <- lint_kind_app (ptext (sLit "coercion") <+> quotes (ppr ty)) + k (map typeKind tys) + ; return () } + +---------------- +lint_kind_app :: SDoc -> Kind -> [Kind] -> LintM Kind +lint_kind_app doc kfn ks = go kfn ks + where + fail_msg = vcat [hang (ptext (sLit "Kind application error in")) 2 doc, + nest 2 (ptext (sLit "Function kind =") <+> ppr kfn), + nest 2 (ptext (sLit "Arg kinds =") <+> ppr ks)] + + go kfn [] = return kfn + go kfn (k:ks) = case splitKindFunTy_maybe kfn of + Nothing -> failWithL fail_msg + Just (kfa, kfb) -> do { unless (k `isSubKind` kfa) + (addErrL fail_msg) + ; go kfb ks } +\end{code} %************************************************************************ %* * @@ -619,6 +820,8 @@ data LintLocInfo | AnExpr CoreExpr -- Some expression | ImportedUnfolding SrcLoc -- Some imported unfolding (ToDo: say which) | TopLevelBindings + | InType Type -- Inside a type + | InCo Coercion -- Inside a coercion \end{code} @@ -671,12 +874,11 @@ inCasePat = LintM $ \ loc _ errs -> (Just (is_case_pat loc), errs) addInScopeVars :: [Var] -> LintM a -> LintM a addInScopeVars vars m - | null dups - = LintM (\ loc subst errs -> unLintM m loc (extendTvInScope subst vars) errs) - | otherwise - = failWithL (dupVars dups) - where - (_, dups) = removeDups compare vars + = LintM (\ loc subst errs -> unLintM m loc (extendTvInScopeList subst vars) errs) + +addInScopeVar :: Var -> LintM a -> LintM a +addInScopeVar var m + = LintM (\ loc subst errs -> unLintM m loc (extendTvInScope subst var) errs) updateTvSubst :: TvSubst -> LintM a -> LintM a updateTvSubst subst' m = @@ -685,12 +887,15 @@ updateTvSubst subst' m = getTvSubst :: LintM TvSubst getTvSubst = LintM (\ _ subst errs -> (Just subst, errs)) -applySubst :: Type -> LintM Type -applySubst ty = do { subst <- getTvSubst; return (substTy subst ty) } +applySubstTy :: Type -> LintM Type +applySubstTy ty = do { subst <- getTvSubst; return (Type.substTy subst ty) } + +applySubstCo :: Coercion -> LintM Coercion +applySubstCo co = do { subst <- getTvSubst; return (substCo (tvCvSubst subst) co) } extendSubstL :: TyVar -> Type -> LintM a -> LintM a extendSubstL tv ty m - = LintM (\ loc subst errs -> unLintM m loc (extendTvSubst subst tv ty) errs) + = LintM (\ loc subst errs -> unLintM m loc (Type.extendTvSubst subst tv ty) errs) \end{code} \begin{code} @@ -718,8 +923,8 @@ checkBndrIdInScope binder id msg = ptext (sLit "is out of scope inside info for") <+> ppr binder -checkTyVarInScope :: TyVar -> LintM () -checkTyVarInScope tv = checkInScope (ptext (sLit "is out of scope")) tv +checkTyCoVarInScope :: TyCoVar -> LintM () +checkTyCoVarInScope v = checkInScope (ptext (sLit "is out of scope")) v checkInScope :: SDoc -> Var -> LintM () checkInScope loc_msg var = @@ -727,11 +932,11 @@ checkInScope loc_msg var = ; checkL (not (mustHaveLocalBinding var) || (var `isInScope` subst)) (hsep [ppr var, loc_msg]) } -checkTys :: Type -> Type -> Message -> LintM () +checkTys :: OutType -> OutType -> Message -> LintM () -- check ty2 is subtype of ty1 (ie, has same structure but usage -- annotations need only be consistent, not equal) -- Assumes ty1,ty2 are have alrady had the substitution applied -checkTys ty1 ty2 msg = checkL (ty1 `coreEqType` ty2) msg +checkTys ty1 ty2 msg = checkL (ty1 `eqType` ty2) msg \end{code} %************************************************************************ @@ -768,6 +973,10 @@ dumpLoc (ImportedUnfolding locn) = (locn, brackets (ptext (sLit "in an imported unfolding"))) dumpLoc TopLevelBindings = (noSrcLoc, empty) +dumpLoc (InType ty) + = (noSrcLoc, text "In the type" <+> quotes (ppr ty)) +dumpLoc (InCo co) + = (noSrcLoc, text "In the coercion" <+> quotes (ppr co)) pp_binders :: [Var] -> SDoc pp_binders bs = sep (punctuate comma (map pp_binder bs)) @@ -859,21 +1068,21 @@ mkNonFunAppMsg fun_ty arg_ty arg hang (ptext (sLit "Arg type:")) 4 (ppr arg_ty), hang (ptext (sLit "Arg:")) 4 (ppr arg)] -mkKindErrMsg :: TyVar -> Type -> Message -mkKindErrMsg tyvar arg_ty - = vcat [ptext (sLit "Kinds don't match in type application:"), - hang (ptext (sLit "Type variable:")) - 4 (ppr tyvar <+> dcolon <+> ppr (tyVarKind tyvar)), - hang (ptext (sLit "Arg type:")) - 4 (ppr arg_ty <+> dcolon <+> ppr (typeKind arg_ty))] - -mkCoAppErrMsg :: TyVar -> Type -> Message -mkCoAppErrMsg tyvar arg_ty - = vcat [ptext (sLit "Kinds don't match in coercion application:"), - hang (ptext (sLit "Coercion variable:")) +mkLetErr :: TyVar -> CoreExpr -> Message +mkLetErr bndr rhs + = vcat [ptext (sLit "Bad `let' binding:"), + hang (ptext (sLit "Variable:")) + 4 (ppr bndr <+> dcolon <+> ppr (varType bndr)), + hang (ptext (sLit "Rhs:")) + 4 (ppr rhs)] + +mkTyCoAppErrMsg :: TyVar -> Coercion -> Message +mkTyCoAppErrMsg tyvar arg_co + = vcat [ptext (sLit "Kinds don't match in lifted coercion application:"), + hang (ptext (sLit "Type variable:")) 4 (ppr tyvar <+> dcolon <+> ppr (tyVarKind tyvar)), hang (ptext (sLit "Arg coercion:")) - 4 (ppr arg_ty <+> dcolon <+> pprEqPred (coercionKind arg_ty))] + 4 (ppr arg_co <+> dcolon <+> pprEqPred (coercionKind arg_co))] mkTyAppMsg :: Type -> Type -> Message mkTyAppMsg ty arg_ty @@ -902,9 +1111,18 @@ mkStrictMsg :: Id -> Message mkStrictMsg binder = vcat [hsep [ptext (sLit "Recursive or top-level binder has strict demand info:"), ppr binder], - hsep [ptext (sLit "Binder's demand info:"), ppr (idNewDemandInfo binder)] + hsep [ptext (sLit "Binder's demand info:"), ppr (idDemandInfo binder)] ] + +mkKindErrMsg :: TyVar -> Type -> Message +mkKindErrMsg tyvar arg_ty + = vcat [ptext (sLit "Kinds don't match in type application:"), + hang (ptext (sLit "Type variable:")) + 4 (ppr tyvar <+> dcolon <+> ppr (tyVarKind tyvar)), + hang (ptext (sLit "Arg type:")) + 4 (ppr arg_ty <+> dcolon <+> ppr (typeKind arg_ty))] + mkArityMsg :: Id -> Message mkArityMsg binder = vcat [hsep [ptext (sLit "Demand type has "), @@ -916,7 +1134,7 @@ mkArityMsg binder hsep [ptext (sLit "Binder's strictness signature:"), ppr dmd_ty] ] - where (StrictSig dmd_ty) = idNewStrictness binder + where (StrictSig dmd_ty) = idStrictness binder mkUnboxedTupleMsg :: Id -> Message mkUnboxedTupleMsg binder @@ -934,4 +1152,62 @@ dupVars :: [[Var]] -> Message dupVars vars = hang (ptext (sLit "Duplicate variables brought into scope")) 2 (ppr vars) + +dupExtVars :: [[Name]] -> Message +dupExtVars vars + = hang (ptext (sLit "Duplicate top-level variables with the same qualified name")) + 2 (ppr vars) \end{code} + +-------------- DEAD CODE ------------------- + +------------------- +checkCoKind :: CoVar -> OutCoercion -> LintM () +-- Both args have had substitution applied +checkCoKind covar arg_co + = do { (s2,t2) <- lintCoercion arg_co + ; unless (s1 `eqType` s2 && t1 `coreEqType` t2) + (addErrL (mkCoAppErrMsg covar arg_co)) } + where + (s1,t1) = coVarKind covar + +lintCoVarKind :: OutCoVar -> LintM () +-- Check the kind of a coercion binder +lintCoVarKind tv + = do { (ty1,ty2) <- lintSplitCoVar tv + ; lintEqType ty1 ty2 + + +------------------- +lintSplitCoVar :: CoVar -> LintM (Type,Type) +lintSplitCoVar cv + = case coVarKind_maybe cv of + Just ts -> return ts + Nothing -> failWithL (sep [ ptext (sLit "Coercion variable with non-equality kind:") + , nest 2 (ppr cv <+> dcolon <+> ppr (tyVarKind cv))]) + +mkCoVarLetErr :: CoVar -> Coercion -> Message +mkCoVarLetErr covar co + = vcat [ptext (sLit "Bad `let' binding for coercion variable:"), + hang (ptext (sLit "Coercion variable:")) + 4 (ppr covar <+> dcolon <+> ppr (coVarKind covar)), + hang (ptext (sLit "Arg coercion:")) + 4 (ppr co)] + +mkCoAppErrMsg :: CoVar -> Coercion -> Message +mkCoAppErrMsg covar arg_co + = vcat [ptext (sLit "Kinds don't match in coercion application:"), + hang (ptext (sLit "Coercion variable:")) + 4 (ppr covar <+> dcolon <+> ppr (coVarKind covar)), + hang (ptext (sLit "Arg coercion:")) + 4 (ppr arg_co <+> dcolon <+> pprEqPred (coercionKind arg_co))] + + +mkCoAppMsg :: Type -> Coercion -> Message +mkCoAppMsg ty arg_co + = vcat [text "Illegal type application:", + hang (ptext (sLit "exp type:")) + 4 (ppr ty <+> dcolon <+> ppr (typeKind ty)), + hang (ptext (sLit "arg type:")) + 4 (ppr arg_co <+> dcolon <+> ppr (coercionKind arg_co))] +