X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypecheck%2FTcIfaceSig.lhs;h=5295fec764f734372e3daabd66614cfa6ad124ce;hb=05afb7485eea44d6410139f8a20c94b6f66c46f2;hp=f83b337f3e35218aa679f4ab28c5295705c5e97b;hpb=a7b95beb6077ff7c330e98c3d5b9268f33b21827;p=ghc-hetmet.git diff --git a/ghc/compiler/typecheck/TcIfaceSig.lhs b/ghc/compiler/typecheck/TcIfaceSig.lhs index f83b337..5295fec 100644 --- a/ghc/compiler/typecheck/TcIfaceSig.lhs +++ b/ghc/compiler/typecheck/TcIfaceSig.lhs @@ -5,24 +5,21 @@ \begin{code} module TcIfaceSig ( tcInterfaceSigs, - tcDelay, - tcVar, tcCoreExpr, tcCoreLamBndrs, tcCoreBinds ) where #include "HsVersions.h" -import HsSyn ( TyClDecl(..), HsTupCon(..) ) +import HsSyn ( CoreDecl(..), TyClDecl(..), HsTupCon(..) ) import TcHsSyn ( TypecheckedCoreBind ) -import TcMonad -import TcMonoType ( tcIfaceType ) -import TcEnv ( RecTcEnv, tcExtendTyVarEnv, - tcExtendGlobalValEnv, tcSetEnv, tcEnvIds, - tcLookupGlobal_maybe, tcLookupRecId_maybe - ) - -import RnHsSyn ( RenamedTyClDecl ) +import TcRnTypes +import TcRnMonad +import TcMonoType ( tcIfaceType, kcHsSigType ) +import TcEnv ( tcExtendTyVarEnv, tcExtendGlobalValEnv, tcLookupGlobalId, + tcLookupDataCon ) + +import RnHsSyn ( RenamedCoreDecl, RenamedTyClDecl ) import HsCore import Literal ( Literal(..) ) import CoreSyn @@ -31,20 +28,20 @@ import CoreUnfold import CoreLint ( lintUnfolding ) import WorkWrap ( mkWrapper ) -import Id ( Id, mkVanillaGlobal, mkLocalId, idName, isDataConWrapId_maybe ) -import Module ( Module ) +import Id ( Id, mkVanillaGlobal, mkLocalId ) import MkId ( mkFCallId ) import IdInfo import TyCon ( tyConDataCons, tyConTyVars ) import DataCon ( DataCon, dataConWorkId, dataConExistentialTyVars, dataConArgTys ) -import Type ( Type, mkTyVarTys, splitTyConApp ) +import Type ( mkTyVarTys, splitTyConApp ) import TysWiredIn ( tupleCon ) import Var ( mkTyVar, tyVarKind ) -import Name ( Name, nameIsLocalOrFrom ) -import ErrUtils ( pprBagOfErrors ) +import Name ( Name ) +import UniqSupply ( initUs_ ) import Outputable import Util ( zipWithEqual, dropList, equalLength ) -import HscTypes ( TyThing(..) ) +import HscTypes ( typeEnvIds ) +import CmdLineOpts ( DynFlag(..) ) \end{code} Ultimately, type signatures in interfaces will have pragmatic @@ -55,137 +52,165 @@ As always, we do not have to worry about user-pragmas in interface signatures. \begin{code} -tcInterfaceSigs :: RecTcEnv -- Envt to use when checking unfoldings - -> Module -- This module - -> [RenamedTyClDecl] -- Ignore non-sig-decls in these decls - -> TcM [Id] +tcInterfaceSigs :: [RenamedTyClDecl] -- Ignore non-sig-decls in these decls + -> TcM TcGblEnv - -tcInterfaceSigs unf_env mod decls - = listTc [ do_one name ty id_infos src_loc - | IfaceSig {tcdName = name, tcdType = ty, tcdIdInfo = id_infos, tcdLoc =src_loc} <- decls] +-- May 2003: +-- NOTE 1: careful about the side-effected EPS +-- in the two tcExtendGlobalValueEnv calls +-- NOTE 2: no point in tying the knot with fixM; all +-- the important knot-tying comes via the PCS global variable + +tcInterfaceSigs decls = + zapEnv (fixM (tc_interface_sigs decls)) `thenM` \ (_,sig_ids) -> + -- The zapEnv dramatically trims the environment, solely + -- to plug the space leak that would otherwise be caused + -- by a rich environment bound into lots of lazy thunks + -- The thunks are the lazily-typechecked IdInfo of the + -- imported things. + + tcExtendGlobalValEnv sig_ids getGblEnv `thenM` \ gbl_env -> + returnM gbl_env + -- We tie a knot so that the Ids read out of interfaces are in scope + -- when we read their pragmas. + -- What we rely on is that pragmas are typechecked lazily; if + -- any type errors are found (ie there's an inconsistency) + -- we silently discard the pragma + -- + -- NOTE ALSO: the knot is in two parts: + -- * Ids defined in this module are added to the typechecker envt + -- which is knot-tied by the fixM. + -- * Imported Ids are side-effected into the PCS by the + -- tcExtendGlobalValueEnv, so they will be seen there provided + -- we don't look them up too early. + -- In both cases, we must defer lookups until after the knot is tied + -- + -- We used to have a much bigger loop (in TcRnDriver), so that the + -- interface pragmas could mention variables bound in this module + -- (by mutual recn), but + -- (a) the knot is tiresomely big, and + -- (b) it black-holes when we have Template Haskell + -- + -- For (b) consider: f = $(...h....) + -- where h is imported, and calls f via an hi-boot file. + -- This is bad! But it is not seen as a staging error, because h + -- is indeed imported. We don't want the type-checker to black-hole + -- when simplifying and compiling the splice! + -- + -- Simple solution: discard any unfolding that mentions a variable + -- bound in this module (and hence not yet processed). + -- The discarding happens when forkM finds a type error. + +tc_interface_sigs decls ~(unf_env, _) + = sequenceM [do_one d | d@(IfaceSig {}) <- decls] `thenM` \ sig_ids -> + tcExtendGlobalValEnv sig_ids getGblEnv `thenM` \ gbl_env -> + returnM (gbl_env, sig_ids) where - in_scope_vars = filter (nameIsLocalOrFrom mod . idName) (tcEnvIds unf_env) - -- Oops: using isLocalId instead can give a black hole - -- because it looks at the idinfo - + in_scope_vars = typeEnvIds (tcg_type_env unf_env) -- When we have hi-boot files, an unfolding might refer to -- something defined in this module, so we must build a -- suitable in-scope set. This thunk will only be poked -- if -dcore-lint is on. - do_one name ty id_infos src_loc - = tcAddSrcLoc src_loc $ - tcAddErrCtxt (ifaceSigCtxt name) $ - tcIfaceType ty `thenTc` \ sigma_ty -> + do_one IfaceSig {tcdName = name, tcdType = ty, + tcdIdInfo = id_infos, tcdLoc = src_loc} + = addSrcLoc src_loc $ + addErrCtxt (ifaceSigCtxt name) $ + tcIfaceType ty `thenM` \ sigma_ty -> tcIdInfo unf_env in_scope_vars name - sigma_ty id_infos `thenTc` \ id_info -> - returnTc (mkVanillaGlobal name sigma_ty id_info) + sigma_ty id_infos `thenM` \ id_info -> + returnM (mkVanillaGlobal name sigma_ty id_info) \end{code} \begin{code} tcIdInfo unf_env in_scope_vars name ty info_ins - = foldlTc tcPrag init_info info_ins + = setGblEnv unf_env $ + -- Use the knot-tied environment for the IdInfo + -- In particular: typechecking unfoldings and worker names + foldlM tcPrag init_info info_ins where - -- set the CgInfo to something sensible but uninformative before - -- we start, because the default CgInfo is a panic. - init_info = vanillaIdInfo `setCgInfo` vanillaCgInfo - - tcPrag info (HsNoCafRefs) = returnTc (info `setCafInfo` NoCafRefs) + -- Set the CgInfo to something sensible but uninformative before + -- we start; default assumption is that it has CAFs + init_info = vanillaIdInfo - tcPrag info (HsArity arity) = - returnTc (info `setArityInfo` arity) + tcPrag info HsNoCafRefs = returnM (info `setCafInfo` NoCafRefs) + tcPrag info (HsArity arity) = returnM (info `setArityInfo` arity) + tcPrag info (HsStrictness str) = returnM (info `setAllStrictnessInfo` Just str) + tcPrag info (HsWorker nm arity) = tcWorkerInfo ty info nm arity tcPrag info (HsUnfold inline_prag expr) - = tcPragExpr unf_env name in_scope_vars expr `thenNF_Tc` \ maybe_expr' -> + = tcPragExpr name in_scope_vars expr `thenM` \ maybe_expr' -> let - -- maybe_expr doesn't get looked at if the unfolding + -- maybe_expr' doesn't get looked at if the unfolding -- is never inspected; so the typecheck doesn't even happen unfold_info = case maybe_expr' of Nothing -> noUnfolding Just expr' -> mkTopUnfolding expr' - info1 = info `setUnfoldingInfo` unfold_info - info2 = info1 `setInlinePragInfo` inline_prag in - returnTc info2 - - tcPrag info (HsStrictness strict_info) - = returnTc (info `setAllStrictnessInfo` Just strict_info) - - tcPrag info (HsWorker nm arity) - = tcWorkerInfo unf_env ty info nm arity + returnM (info `setUnfoldingInfoLazily` unfold_info + `setInlinePragInfo` inline_prag) \end{code} \begin{code} -tcWorkerInfo unf_env ty info worker_name arity - = uniqSMToTcM (mkWrapper ty strict_sig) `thenNF_Tc` \ wrap_fn -> - let +tcWorkerInfo ty info wkr_name arity + = forkM doc (tcVar wkr_name) `thenM` \ maybe_wkr_id -> -- Watch out! We can't pull on unf_env too eagerly! - info' = case tcLookupRecId_maybe unf_env worker_name of - Just worker_id -> - info `setUnfoldingInfo` mkTopUnfolding (wrap_fn worker_id) - `setWorkerInfo` HasWorker worker_id arity + -- Hence the forkM + + -- We return without testing maybe_wkr_id, but as soon as info is + -- looked at we will test it. That's ok, because its outside the + -- knot; and there seems no big reason to further defer the + -- tcVar lookup. (Contrast with tcPragExpr, where postponing walking + -- over the unfolding until it's actually used does seem worth while.) + newUniqueSupply `thenM` \ us -> + returnM (case maybe_wkr_id of + Nothing -> info + Just wkr_id -> info `setUnfoldingInfoLazily` mk_unfolding us wkr_id + `setWorkerInfo` HasWorker wkr_id arity) - Nothing -> pprTrace "tcWorkerInfo failed:" - (ppr worker_name) info - in - returnTc info' where + doc = text "worker for" <+> ppr wkr_name + + mk_unfolding us wkr_id = mkTopUnfolding (initUs_ us (mkWrapper ty strict_sig) wkr_id) + -- We are relying here on strictness info always appearing -- before worker info, fingers crossed .... - strict_sig = case newStrictnessInfo info of - Just sig -> sig - Nothing -> pprPanic "Worker info but no strictness for" (ppr worker_name) + strict_sig = case newStrictnessInfo info of + Just sig -> sig + Nothing -> pprPanic "Worker info but no strictness for" (ppr wkr_name) \end{code} For unfoldings we try to do the job lazily, so that we never type check an unfolding that isn't going to be looked at. \begin{code} -tcPragExpr unf_env name in_scope_vars expr - = tcDelay unf_env doc Nothing $ - tcCoreExpr expr `thenTc` \ core_expr' -> +tcPragExpr :: Name -> [Id] -> UfExpr Name -> TcM (Maybe CoreExpr) +tcPragExpr name in_scope_vars expr + = forkM doc $ + tcCoreExpr expr `thenM` \ core_expr' -> -- Check for type consistency in the unfolding - tcGetSrcLoc `thenNF_Tc` \ src_loc -> - getDOptsTc `thenNF_Tc` \ dflags -> - case lintUnfolding dflags src_loc in_scope_vars core_expr' of - (Nothing,_) -> returnTc (Just core_expr') -- ignore warnings - (Just fail_msg,_) -> failWithTc ((doc <+> text "failed Lint") $$ fail_msg) + ifOptM Opt_DoCoreLinting ( + getSrcLocM `thenM` \ src_loc -> + case lintUnfolding src_loc in_scope_vars core_expr' of + Nothing -> returnM () + Just fail_msg -> failWithTc ((doc <+> text "Failed Lint") $$ fail_msg) + ) `thenM_` + + returnM core_expr' where doc = text "unfolding of" <+> ppr name - -tcDelay :: RecTcEnv -> SDoc -> a -> TcM a -> NF_TcM a -tcDelay unf_env doc bad_ans thing_inside - = forkNF_Tc ( - recoverNF_Tc bad_value ( - tcSetEnv unf_env thing_inside - )) - where - -- The trace tells what wasn't available, for the benefit of - -- compiler hackers who want to improve it! - bad_value = getErrsTc `thenNF_Tc` \ (warns,errs) -> - returnNF_Tc (pprTrace "Failed:" - (hang doc 4 (pprBagOfErrors errs)) - bad_ans) \end{code} Variables in unfoldings ~~~~~~~~~~~~~~~~~~~~~~~ -****** Inside here we use only the Global environment, even for locally bound variables. -****** Why? Because we know all the types and want to bind them to real Ids. \begin{code} tcVar :: Name -> TcM Id -tcVar name - = tcLookupGlobal_maybe name `thenNF_Tc` \ maybe_id -> - case maybe_id of { - Just (AnId id) -> returnTc id ; - Nothing -> failWithTc (noDecl name) - } - -noDecl name = hsep [ptext SLIT("Warning: no binding for"), ppr name] + -- Inside here we use only the Global environment, even for locally bound variables. + -- Why? Because we know all the types and want to bind them to real Ids. +tcVar name = tcLookupGlobalId name \end{code} UfCore expressions. @@ -194,87 +219,87 @@ UfCore expressions. tcCoreExpr :: UfExpr Name -> TcM CoreExpr tcCoreExpr (UfType ty) - = tcIfaceType ty `thenTc` \ ty' -> + = tcIfaceType ty `thenM` \ ty' -> -- It might not be of kind type - returnTc (Type ty') + returnM (Type ty') tcCoreExpr (UfVar name) - = tcVar name `thenTc` \ id -> - returnTc (Var id) + = tcVar name `thenM` \ id -> + returnM (Var id) tcCoreExpr (UfLit lit) - = returnTc (Lit lit) + = returnM (Lit lit) -- The dreaded lit-lits are also similar, except here the type -- is read in explicitly rather than being implicit tcCoreExpr (UfLitLit lit ty) - = tcIfaceType ty `thenTc` \ ty' -> - returnTc (Lit (MachLitLit lit ty')) + = tcIfaceType ty `thenM` \ ty' -> + returnM (Lit (MachLitLit lit ty')) tcCoreExpr (UfFCall cc ty) - = tcIfaceType ty `thenTc` \ ty' -> - tcGetUnique `thenNF_Tc` \ u -> - returnTc (Var (mkFCallId u cc ty')) + = tcIfaceType ty `thenM` \ ty' -> + newUnique `thenM` \ u -> + returnM (Var (mkFCallId u cc ty')) -tcCoreExpr (UfTuple (HsTupCon _ boxity arity) args) - = mapTc tcCoreExpr args `thenTc` \ args' -> +tcCoreExpr (UfTuple (HsTupCon boxity arity) args) + = mappM tcCoreExpr args `thenM` \ args' -> let -- Put the missing type arguments back in con_args = map (Type . exprType) args' ++ args' in - returnTc (mkApps (Var con_id) con_args) + returnM (mkApps (Var con_id) con_args) where con_id = dataConWorkId (tupleCon boxity arity) tcCoreExpr (UfLam bndr body) = tcCoreLamBndr bndr $ \ bndr' -> - tcCoreExpr body `thenTc` \ body' -> - returnTc (Lam bndr' body') + tcCoreExpr body `thenM` \ body' -> + returnM (Lam bndr' body') tcCoreExpr (UfApp fun arg) - = tcCoreExpr fun `thenTc` \ fun' -> - tcCoreExpr arg `thenTc` \ arg' -> - returnTc (App fun' arg') + = tcCoreExpr fun `thenM` \ fun' -> + tcCoreExpr arg `thenM` \ arg' -> + returnM (App fun' arg') tcCoreExpr (UfCase scrut case_bndr alts) - = tcCoreExpr scrut `thenTc` \ scrut' -> + = tcCoreExpr scrut `thenM` \ scrut' -> let scrut_ty = exprType scrut' case_bndr' = mkLocalId case_bndr scrut_ty in tcExtendGlobalValEnv [case_bndr'] $ - mapTc (tcCoreAlt scrut_ty) alts `thenTc` \ alts' -> - returnTc (Case scrut' case_bndr' alts') + mappM (tcCoreAlt scrut_ty) alts `thenM` \ alts' -> + returnM (Case scrut' case_bndr' alts') tcCoreExpr (UfLet (UfNonRec bndr rhs) body) - = tcCoreExpr rhs `thenTc` \ rhs' -> + = tcCoreExpr rhs `thenM` \ rhs' -> tcCoreValBndr bndr $ \ bndr' -> - tcCoreExpr body `thenTc` \ body' -> - returnTc (Let (NonRec bndr' rhs') body') + tcCoreExpr body `thenM` \ body' -> + returnM (Let (NonRec bndr' rhs') body') tcCoreExpr (UfLet (UfRec pairs) body) = tcCoreValBndrs bndrs $ \ bndrs' -> - mapTc tcCoreExpr rhss `thenTc` \ rhss' -> - tcCoreExpr body `thenTc` \ body' -> - returnTc (Let (Rec (bndrs' `zip` rhss')) body') + mappM tcCoreExpr rhss `thenM` \ rhss' -> + tcCoreExpr body `thenM` \ body' -> + returnM (Let (Rec (bndrs' `zip` rhss')) body') where (bndrs, rhss) = unzip pairs tcCoreExpr (UfNote note expr) - = tcCoreExpr expr `thenTc` \ expr' -> + = tcCoreExpr expr `thenM` \ expr' -> case note of - UfCoerce to_ty -> tcIfaceType to_ty `thenTc` \ to_ty' -> - returnTc (Note (Coerce to_ty' + UfCoerce to_ty -> tcIfaceType to_ty `thenM` \ to_ty' -> + returnM (Note (Coerce to_ty' (exprType expr')) expr') - UfInlineCall -> returnTc (Note InlineCall expr') - UfInlineMe -> returnTc (Note InlineMe expr') - UfSCC cc -> returnTc (Note (SCC cc) expr') + UfInlineCall -> returnM (Note InlineCall expr') + UfInlineMe -> returnM (Note InlineMe expr') + UfSCC cc -> returnM (Note (SCC cc) expr') \end{code} \begin{code} tcCoreLamBndr (UfValBinder name ty) thing_inside - = tcIfaceType ty `thenTc` \ ty' -> + = tcIfaceType ty `thenM` \ ty' -> let id = mkLocalId name ty' in @@ -294,7 +319,7 @@ tcCoreLamBndrs (b:bs) thing_inside thing_inside (b':bs') tcCoreValBndr (UfValBinder name ty) thing_inside - = tcIfaceType ty `thenTc` \ ty' -> + = tcIfaceType ty `thenM` \ ty' -> let id = mkLocalId name ty' in @@ -302,7 +327,7 @@ tcCoreValBndr (UfValBinder name ty) thing_inside thing_inside id tcCoreValBndrs bndrs thing_inside -- Expect them all to be ValBinders - = mapTc tcIfaceType tys `thenTc` \ tys' -> + = mappM tcIfaceType tys `thenM` \ tys' -> let ids = zipWithEqual "tcCoreValBndr" mkLocalId names tys' in @@ -316,25 +341,25 @@ tcCoreValBndrs bndrs thing_inside -- Expect them all to be ValBinders \begin{code} tcCoreAlt scrut_ty (UfDefault, names, rhs) = ASSERT( null names ) - tcCoreExpr rhs `thenTc` \ rhs' -> - returnTc (DEFAULT, [], rhs') + tcCoreExpr rhs `thenM` \ rhs' -> + returnM (DEFAULT, [], rhs') tcCoreAlt scrut_ty (UfLitAlt lit, names, rhs) = ASSERT( null names ) - tcCoreExpr rhs `thenTc` \ rhs' -> - returnTc (LitAlt lit, [], rhs') + tcCoreExpr rhs `thenM` \ rhs' -> + returnM (LitAlt lit, [], rhs') tcCoreAlt scrut_ty (UfLitLitAlt str ty, names, rhs) = ASSERT( null names ) - tcCoreExpr rhs `thenTc` \ rhs' -> - tcIfaceType ty `thenTc` \ ty' -> - returnTc (LitAlt (MachLitLit str ty'), [], rhs') + tcCoreExpr rhs `thenM` \ rhs' -> + tcIfaceType ty `thenM` \ ty' -> + returnM (LitAlt (MachLitLit str ty'), [], rhs') -- A case alternative is made quite a bit more complicated -- by the fact that we omit type annotations because we can -- work them out. True enough, but its not that easy! tcCoreAlt scrut_ty alt@(con, names, rhs) - = tcConAlt con `thenTc` \ con -> + = tcConAlt con `thenM` \ con -> let ex_tyvars = dataConExistentialTyVars con (tycon, inst_tys) = splitTyConApp scrut_ty -- NB: not tcSplitTyConApp @@ -357,19 +382,18 @@ tcCoreAlt scrut_ty alt@(con, names, rhs) ASSERT( con `elem` tyConDataCons tycon && equalLength inst_tys main_tyvars ) tcExtendTyVarEnv ex_tyvars' $ tcExtendGlobalValEnv arg_ids $ - tcCoreExpr rhs `thenTc` \ rhs' -> - returnTc (DataAlt con, ex_tyvars' ++ arg_ids, rhs') + tcCoreExpr rhs `thenM` \ rhs' -> + returnM (DataAlt con, ex_tyvars' ++ arg_ids, rhs') tcConAlt :: UfConAlt Name -> TcM DataCon -tcConAlt (UfTupleAlt (HsTupCon _ boxity arity)) - = returnTc (tupleCon boxity arity) - -tcConAlt (UfDataAlt con_name) - = tcVar con_name `thenTc` \ con_id -> - returnTc (case isDataConWrapId_maybe con_id of - Just con -> con - Nothing -> pprPanic "tcCoreAlt" (ppr con_id)) +tcConAlt (UfTupleAlt (HsTupCon boxity arity)) + = returnM (tupleCon boxity arity) + +tcConAlt (UfDataAlt con_name) -- When reading interface files + -- the con_name will be the real name of + -- the data con + = tcLookupDataCon con_name \end{code} %************************************************************************ @@ -380,21 +404,29 @@ tcConAlt (UfDataAlt con_name) \begin{code} -tcCoreBinds :: [RenamedTyClDecl] -> TcM [TypecheckedCoreBind] +tcCoreBinds :: [RenamedCoreDecl] -> TcM [TypecheckedCoreBind] -- We don't assume the bindings are in dependency order -- So first build the environment, then check the RHSs -tcCoreBinds ls = mapTc tcCoreBinder ls `thenTc` \ bndrs -> +tcCoreBinds ls = mappM tcCoreBinder ls `thenM` \ bndrs -> tcExtendGlobalValEnv bndrs $ - mapTc tcCoreBind ls - -tcCoreBinder (CoreDecl { tcdName = nm, tcdType = ty }) - = tcIfaceType ty `thenTc` \ ty' -> - returnTc (mkLocalId nm ty') - -tcCoreBind (CoreDecl { tcdName = nm, tcdRhs = rhs }) - = tcVar nm `thenTc` \ id -> - tcCoreExpr rhs `thenTc` \ rhs' -> - returnTc (id, rhs') + mappM (tcCoreBind bndrs) ls + +tcCoreBinder (CoreDecl nm ty _ _) + = kcHsSigType ty `thenM_` + tcIfaceType ty `thenM` \ ty' -> + returnM (mkLocalId nm ty') + +tcCoreBind bndrs (CoreDecl nm _ rhs loc) + = tcVar nm `thenM` \ id -> + tcCoreExpr rhs `thenM` \ rhs' -> + let + mb_err = lintUnfolding loc bndrs rhs' + in + (case mb_err of + Just err -> addErr err + Nothing -> returnM ()) `thenM_` + + returnM (id, rhs') \end{code}