X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2FbasicTypes%2FMkId.lhs;h=32b4ecfed06cdbbcf1c375d910ece5edb53d2815;hp=93369f5cc33059480933e6b544725e90e2dc3239;hb=6a05ec5ef5373f61b7f9f5bdc344483417fa801b;hpb=19e64b50409a331ddf816cb4c7f33d646dabd43a diff --git a/compiler/basicTypes/MkId.lhs b/compiler/basicTypes/MkId.lhs index 93369f5..32b4ecf 100644 --- a/compiler/basicTypes/MkId.lhs +++ b/compiler/basicTypes/MkId.lhs @@ -1,7 +1,7 @@ -% +\% +% (c) The University of Glasgow 2006 % (c) The AQUA Project, Glasgow University, 1998 % -\section[StdIdInfo]{Standard unfoldings} This module contains definitions for the IdInfo for things that have a standard form, namely: @@ -12,15 +12,23 @@ have a standard form, namely: * primitive operations \begin{code} +{-# OPTIONS -w #-} +-- The above warning supression flag is a temporary kludge. +-- While working on this module you are encouraged to remove it and fix +-- any warnings in the module. See +-- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings +-- for details + module MkId ( mkDictFunId, mkDefaultMethodId, mkDictSelId, mkDataConIds, mkRecordSelId, - mkPrimOpId, mkFCallId, + mkPrimOpId, mkFCallId, mkTickBoxOpId, mkBreakPointOpId, mkReboxingAlt, wrapNewTypeBody, unwrapNewTypeBody, + wrapFamInstBody, unwrapFamInstScrut, mkUnpackCase, mkProductBox, -- And some particular Ids; see below for why they are wired in @@ -38,67 +46,42 @@ module MkId ( #include "HsVersions.h" - -import BasicTypes ( Arity, StrictnessMark(..), isMarkedUnboxed, isMarkedStrict ) -import Rules ( mkSpecInfo ) -import TysPrim ( openAlphaTyVars, alphaTyVar, alphaTy, - realWorldStatePrimTy, addrPrimTy - ) -import TysWiredIn ( charTy, mkListTy ) -import PrelRules ( primOpRules ) -import Type ( TyThing(..), mkForAllTy, tyVarsOfTypes, - newTyConInstRhs, mkTopTvSubst, substTyVar ) -import TcGadt ( gadtRefine, refineType, emptyRefinement ) -import HsBinds ( ExprCoFn(..), isIdCoercion ) -import Coercion ( mkSymCoercion, mkUnsafeCoercion, isEqPred ) -import TcType ( Type, ThetaType, mkDictTy, mkPredTys, mkPredTy, - mkTyConApp, mkTyVarTys, mkClassPred, isPredTy, - mkFunTys, mkFunTy, mkSigmaTy, tcSplitSigmaTy, tcEqType, - isUnLiftedType, mkForAllTys, mkTyVarTy, tyVarsOfType, - tcSplitFunTys, tcSplitForAllTys, dataConsStupidTheta - ) -import CoreUtils ( exprType, dataConOrigInstPat ) -import CoreUnfold ( mkTopUnfolding, mkCompulsoryUnfolding ) -import Literal ( nullAddrLit, mkStringLit ) -import TyCon ( TyCon, isNewTyCon, tyConDataCons, FieldLabel, - tyConStupidTheta, isProductTyCon, isDataTyCon, isRecursiveTyCon, - newTyConCo ) -import Class ( Class, classTyCon, classSelIds ) -import Var ( Id, TyVar, Var, setIdType ) -import VarSet ( isEmptyVarSet, subVarSet, varSetElems ) -import Name ( mkFCallName, mkWiredInName, Name, BuiltInSyntax(..)) -import OccName ( mkOccNameFS, varName ) -import PrimOp ( PrimOp, primOpSig, primOpOcc, primOpTag ) -import ForeignCall ( ForeignCall ) -import DataCon ( DataCon, DataConIds(..), dataConTyCon, dataConUnivTyVars, - dataConFieldLabels, dataConRepArity, dataConResTys, - dataConRepArgTys, dataConRepType, dataConFullSig, - dataConStrictMarks, dataConExStricts, - splitProductType, isVanillaDataCon, dataConFieldType, - deepSplitProductType - ) -import Id ( idType, mkGlobalId, mkVanillaGlobal, mkSysLocal, - mkTemplateLocals, mkTemplateLocalsNum, mkExportedLocalId, - mkTemplateLocal, idName - ) -import IdInfo ( IdInfo, noCafIdInfo, setUnfoldingInfo, - setArityInfo, setSpecInfo, setCafInfo, - setAllStrictnessInfo, vanillaIdInfo, - GlobalIdDetails(..), CafInfo(..) - ) -import NewDemand ( mkStrictSig, DmdResult(..), - mkTopDmdType, topDmd, evalDmd, lazyDmd, retCPR, - Demand(..), Demands(..) ) -import DmdAnal ( dmdAnalTopRhs ) +import Rules +import TysPrim +import TysWiredIn +import PrelRules +import Type +import TypeRep +import TcGadt +import Coercion +import TcType +import CoreUtils +import CoreUnfold +import Literal +import TyCon +import Class +import VarSet +import Name +import OccName +import PrimOp +import ForeignCall +import DataCon +import Id +import Var ( Var, TyVar, mkCoVar) +import IdInfo +import NewDemand +import DmdAnal import CoreSyn -import Unique ( mkBuiltinUnique, mkPrimOpIdUnique ) +import Unique import Maybes import PrelNames -import Util ( dropList, isSingleton ) +import BasicTypes hiding ( SuccessFlag(..) ) +import Util import Outputable import FastString -import ListSetOps ( assoc, minusList ) -\end{code} +import ListSetOps +import Module +\end{code} %************************************************************************ %* * @@ -187,36 +170,69 @@ Notice that Making an explicit case expression allows the simplifier to eliminate it in the (common) case where the constructor arg is already evaluated. +Note [Wrappers for data instance tycons] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +In the case of data instances, the wrapper also applies the coercion turning +the representation type into the family instance type to cast the result of +the wrapper. For example, consider the declarations + + data family Map k :: * -> * + data instance Map (a, b) v = MapPair (Map a (Pair b v)) + +The tycon to which the datacon MapPair belongs gets a unique internal +name of the form :R123Map, and we call it the representation tycon. +In contrast, Map is the family tycon (accessible via +tyConFamInst_maybe). A coercion allows you to move between +representation and family type. It is accessible from :R123Map via +tyConFamilyCoercion_maybe and has kind + + Co123Map a b v :: {Map (a, b) v :=: :R123Map a b v} + +The wrapper and worker of MapPair get the types + + -- Wrapper + $WMapPair :: forall a b v. Map a (Map a b v) -> Map (a, b) v + $WMapPair a b v = MapPair a b v `cast` sym (Co123Map a b v) + + -- Worker + MapPair :: forall a b v. Map a (Map a b v) -> :R123Map a b v + +This coercion is conditionally applied by wrapFamInstBody. + +It's a bit more complicated if the data instance is a GADT as well! + + data instance T [a] where + T1 :: forall b. b -> T [Maybe b] +Hence + Co7T a :: T [a] ~ :R7T a + +Now we want + + -- Wrapper + $WT1 :: forall b. b -> T [Maybe b] + $WT1 b v = T1 (Maybe b) b (Maybe b) v + `cast` sym (Co7T (Maybe b)) + + -- Worker + T1 :: forall c b. (c ~ Maybe b) => b -> :R7T c \begin{code} mkDataConIds :: Name -> Name -> DataCon -> DataConIds mkDataConIds wrap_name wkr_name data_con - | isNewTyCon tycon - = DCIds Nothing nt_work_id -- Newtype, only has a worker + | isNewTyCon tycon -- Newtype, only has a worker + = DCIds Nothing nt_work_id - | any isMarkedStrict all_strict_marks -- Algebraic, needs wrapper - || not (null eq_spec) + | any isMarkedStrict all_strict_marks -- Algebraic, needs wrapper + || not (null eq_spec) -- NB: LoadIface.ifaceDeclSubBndrs + || isFamInstTyCon tycon -- depends on this test = DCIds (Just alg_wrap_id) wrk_id - | otherwise -- Algebraic, no wrapper + | otherwise -- Algebraic, no wrapper = DCIds Nothing wrk_id where - (univ_tvs, ex_tvs, eq_spec, theta, orig_arg_tys) = dataConFullSig data_con - tycon = dataConTyCon data_con - - ----------- Wrapper -------------- - -- We used to include the stupid theta in the wrapper's args - -- but now we don't. Instead the type checker just injects these - -- extra constraints where necessary. - wrap_tvs = (univ_tvs `minusList` map fst eq_spec) ++ ex_tvs - subst = mkTopTvSubst eq_spec - dict_tys = mkPredTys theta - result_ty_args = map (substTyVar subst) univ_tvs - result_ty = mkTyConApp tycon result_ty_args - wrap_ty = mkForAllTys wrap_tvs $ mkFunTys dict_tys $ - mkFunTys orig_arg_tys $ result_ty - -- NB: watch out here if you allow user-written equality - -- constraints in data constructor signatures + (univ_tvs, ex_tvs, eq_spec, + eq_theta, dict_theta, orig_arg_tys, res_ty) = dataConFullSig data_con + tycon = dataConTyCon data_con -- The representation TyCon (not family) ----------- Worker (algebraic data types only) -------------- -- The *worker* for the data constructor is the function that @@ -232,6 +248,7 @@ mkDataConIds wrap_name wkr_name data_con -- even if arity = 0 wkr_sig = mkStrictSig (mkTopDmdType (replicate wkr_arity topDmd) cpr_info) + -- Note [Data-con worker strictness] -- Notice that we do *not* say the worker is strict -- even if the data constructor is declared strict -- e.g. data T = MkT !(Int,Int) @@ -256,29 +273,49 @@ mkDataConIds wrap_name wkr_name data_con -- RetCPR is only true for products that are real data types; -- that is, not unboxed tuples or [non-recursive] newtypes - ----------- Wrappers for newtypes -------------- + ----------- Workers for newtypes -------------- nt_work_id = mkGlobalId (DataConWrapId data_con) wkr_name wrap_ty nt_work_info nt_work_info = noCafIdInfo -- The NoCaf-ness is set by noCafIdInfo `setArityInfo` 1 -- Arity 1 `setUnfoldingInfo` newtype_unf - newtype_unf = ASSERT( isVanillaDataCon data_con && - isSingleton orig_arg_tys ) + newtype_unf = -- The assertion below is no longer correct: + -- there may be a dict theta rather than a singleton orig_arg_ty + -- ASSERT( isVanillaDataCon data_con && + -- isSingleton orig_arg_tys ) + -- -- No existentials on a newtype, but it can have a context -- e.g. newtype Eq a => T a = MkT (...) mkCompulsoryUnfolding $ mkLams wrap_tvs $ Lam id_arg1 $ - wrapNewTypeBody tycon result_ty_args + wrapNewTypeBody tycon res_ty_args (Var id_arg1) - id_arg1 = mkTemplateLocal 1 (head orig_arg_tys) + id_arg1 = mkTemplateLocal 1 + (if null orig_arg_tys + then ASSERT(not (null $ dataConDictTheta data_con)) mkPredTy $ head (dataConDictTheta data_con) + else head orig_arg_tys + ) + + ----------- Wrapper -------------- + -- We used to include the stupid theta in the wrapper's args + -- but now we don't. Instead the type checker just injects these + -- extra constraints where necessary. + wrap_tvs = (univ_tvs `minusList` map fst eq_spec) ++ ex_tvs + res_ty_args = substTyVars (mkTopTvSubst eq_spec) univ_tvs + eq_tys = mkPredTys eq_theta + dict_tys = mkPredTys dict_theta + wrap_ty = mkForAllTys wrap_tvs $ mkFunTys eq_tys $ mkFunTys dict_tys $ + mkFunTys orig_arg_tys $ res_ty + -- NB: watch out here if you allow user-written equality + -- constraints in data constructor signatures ----------- Wrappers for algebraic data types -------------- alg_wrap_id = mkGlobalId (DataConWrapId data_con) wrap_name wrap_ty alg_wrap_info alg_wrap_info = noCafIdInfo -- The NoCaf-ness is set by noCafIdInfo - `setArityInfo` alg_arity + `setArityInfo` wrap_arity -- It's important to specify the arity, so that partial -- applications are treated as values - `setUnfoldingInfo` alg_unf + `setUnfoldingInfo` wrap_unf `setAllStrictnessInfo` Just wrap_sig all_strict_marks = dataConExStricts data_con ++ dataConStrictMarks data_con @@ -295,21 +332,30 @@ mkDataConIds wrap_name wkr_name data_con -- ...(let w = C x in ...(w p q)...)... -- we want to see that w is strict in its two arguments - alg_unf = mkTopUnfolding $ Note InlineMe $ + wrap_unf = mkTopUnfolding $ Note InlineMe $ mkLams wrap_tvs $ + mkLams eq_args $ mkLams dict_args $ mkLams id_args $ foldr mk_case con_app (zip (dict_args ++ id_args) all_strict_marks) i3 [] - con_app _ rep_ids = Var wrk_id `mkTyApps` result_ty_args - `mkVarApps` ex_tvs - `mkTyApps` map snd eq_spec - `mkVarApps` reverse rep_ids + con_app _ rep_ids = wrapFamInstBody tycon res_ty_args $ + Var wrk_id `mkTyApps` res_ty_args + `mkVarApps` ex_tvs + `mkTyApps` map snd eq_spec -- Equality evidence + `mkVarApps` eq_args + `mkVarApps` reverse rep_ids (dict_args,i2) = mkLocals 1 dict_tys (id_args,i3) = mkLocals i2 orig_arg_tys - alg_arity = i3-1 + wrap_arity = i3-1 + (eq_args,_) = mkCoVarLocals i3 eq_tys + + mkCoVarLocals i [] = ([],i) + mkCoVarLocals i (x:xs) = let (ys,j) = mkCoVarLocals (i+1) xs + y = mkCoVar (mkSysTvName (mkBuiltinUnique i) FSLIT("dc_co")) x + in (y:ys,j) mk_case :: (Id, StrictnessMark) -- Arg, strictness @@ -323,7 +369,7 @@ mkDataConIds wrap_name wkr_name data_con MarkedStrict | isUnLiftedType (idType arg) -> body i (arg:rep_args) | otherwise -> - Case (Var arg) arg result_ty [(DEFAULT,[], body i (arg:rep_args))] + Case (Var arg) arg res_ty [(DEFAULT,[], body i (arg:rep_args))] MarkedUnboxed -> unboxProduct i (Var arg) (idType arg) the_body @@ -424,39 +470,75 @@ Note the forall'd tyvars of the selector are just the free tyvars of the result type; there may be other tyvars in the constructor's type (e.g. 'b' in T2). -\begin{code} +Note [Selector running example] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +It's OK to combine GADTs and type families. Here's a running example: + + data instance T [a] where + T1 { fld :: b } :: T [Maybe b] + +The representation type looks like this + data :R7T a where + T1 { fld :: b } :: :R7T (Maybe b) + +and there's coercion from the family type to the representation type + :CoR7T a :: T [a] ~ :R7T a + +The selector we want for fld looks like this: --- Steps for handling "naughty" vs "non-naughty" selectors: --- 1. Determine naughtiness by comparing field type vs result type --- 2. Install naughty ones with selector_ty of type _|_ and fill in mzero for info --- 3. If it's not naughty, do the normal plan. + fld :: forall b. T [Maybe b] -> b + fld = /\b. \(d::T [Maybe b]). + case d `cast` :CoR7T (Maybe b) of + T1 (x::b) -> x +The scrutinee of the case has type :R7T (Maybe b), which can be +gotten by appying the eq_spec to the univ_tvs of the data con. + +\begin{code} mkRecordSelId :: TyCon -> FieldLabel -> Id mkRecordSelId tycon field_label -- Assumes that all fields with the same field label have the same type - | is_naughty = naughty_id - | otherwise = sel_id + = sel_id where - is_naughty = not (tyVarsOfType field_ty `subVarSet` res_tv_set) - sel_id_details = RecordSelId tycon field_label is_naughty + -- Because this function gets called by implicitTyThings, we need to + -- produce the OccName of the Id without doing any suspend type checks. + -- (see the note [Tricky iface loop]). + -- A suspended type-check is sometimes necessary to compute field_ty, + -- so we need to make sure that we suspend anything that depends on field_ty. + + -- the overall result + sel_id = mkGlobalId sel_id_details field_label theType theInfo + + -- check whether the type is naughty: this thunk does not get forced + -- until the type is actually needed + field_ty = dataConFieldType con1 field_label + is_naughty = not (tyVarsOfType field_ty `subVarSet` data_tv_set) + + -- it's important that this doesn't force the if + (theType, theInfo) = if is_naughty + -- Escapist case here for naughty constructors + -- We give it no IdInfo, and a type of forall a.a (never looked at) + then (forall_a_a, noCafIdInfo) + -- otherwise do the real case + else (selector_ty, info) + + sel_id_details = RecordSelId { sel_tycon = tycon, sel_label = field_label, sel_naughty = is_naughty } + -- For a data type family, the tycon is the *instance* TyCon - -- Escapist case here for naughty construcotrs - -- We give it no IdInfo, and a type of forall a.a (never looked at) - naughty_id = mkGlobalId sel_id_details field_label forall_a_a noCafIdInfo + -- for naughty case forall_a_a = mkForAllTy alphaTyVar (mkTyVarTy alphaTyVar) - -- Normal case starts here - sel_id = mkGlobalId sel_id_details field_label selector_ty info + -- real case starts here: data_cons = tyConDataCons tycon data_cons_w_field = filter has_field data_cons -- Can't be empty! has_field con = field_label `elem` dataConFieldLabels con - con1 = head data_cons_w_field - res_tys = dataConResTys con1 - res_tv_set = tyVarsOfTypes res_tys - res_tvs = varSetElems res_tv_set - data_ty = mkTyConApp tycon res_tys - field_ty = dataConFieldType con1 field_label + con1 = ASSERT( not (null data_cons_w_field) ) head data_cons_w_field + (univ_tvs, _, eq_spec, _, _, _, data_ty) = dataConFullSig con1 + -- For a data type family, the data_ty (and hence selector_ty) mentions + -- only the family TyCon, not the instance TyCon + data_tv_set = tyVarsOfType data_ty + data_tvs = varSetElems data_tv_set -- *Very* tiresomely, the selectors are (unnecessarily!) overloaded over -- just the dictionaries in the types of the constructors that contain @@ -470,10 +552,9 @@ mkRecordSelId tycon field_label n_stupid_dicts = length stupid_dict_tys (field_tyvars,pre_field_theta,field_tau) = tcSplitSigmaTy field_ty - - field_theta = filter (not . isEqPred) pre_field_theta - field_dict_tys = mkPredTys field_theta - n_field_dict_tys = length field_dict_tys + field_theta = filter (not . isEqPred) pre_field_theta + field_dict_tys = mkPredTys field_theta + n_field_dict_tys = length field_dict_tys -- If the field has a universally quantified type we have to -- be a bit careful. Suppose we have -- data R = R { op :: forall a. Foo a => a -> a } @@ -490,7 +571,7 @@ mkRecordSelId tycon field_label -- op (R op) = op selector_ty :: Type - selector_ty = mkForAllTys res_tvs $ mkForAllTys field_tyvars $ + selector_ty = mkForAllTys data_tvs $ mkForAllTys field_tyvars $ mkFunTys stupid_dict_tys $ mkFunTys field_dict_tys $ mkFunTy data_ty field_tau @@ -517,7 +598,8 @@ mkRecordSelId tycon field_label field_dict_ids = mkTemplateLocalsNum field_dict_base field_dict_tys dict_id_base = field_dict_base + n_field_dict_tys data_id = mkTemplateLocal dict_id_base data_ty - arg_base = dict_id_base + 1 + scrut_id = mkTemplateLocal (dict_id_base+1) scrut_ty + arg_base = dict_id_base + 2 the_alts :: [CoreAlt] the_alts = map mk_alt data_cons_w_field -- Already sorted by data-con @@ -530,14 +612,19 @@ mkRecordSelId tycon field_label caf_info | no_default = NoCafRefs | otherwise = MayHaveCafRefs - sel_rhs = mkLams res_tvs $ mkLams field_tyvars $ + sel_rhs = mkLams data_tvs $ mkLams field_tyvars $ mkLams stupid_dict_ids $ mkLams field_dict_ids $ - Lam data_id $ mk_result sel_body + Lam data_id $ mk_result sel_body + + scrut_ty_args = substTyVars (mkTopTvSubst eq_spec) univ_tvs + scrut_ty = mkTyConApp tycon scrut_ty_args + scrut = unwrapFamInstScrut tycon scrut_ty_args (Var data_id) + -- First coerce from the type family to the representation type -- NB: A newtype always has a vanilla DataCon; no existentials etc - -- res_tys will simply be the dataConUnivTyVars - sel_body | isNewTyCon tycon = unwrapNewTypeBody tycon res_tys (Var data_id) - | otherwise = Case (Var data_id) data_id field_ty (default_alt ++ the_alts) + -- data_tys will simply be the dataConUnivTyVars + sel_body | isNewTyCon tycon = unwrapNewTypeBody tycon scrut_ty_args scrut + | otherwise = Case scrut scrut_id field_ty (default_alt ++ the_alts) mk_result poly_result = mkVarApps (mkVarApps poly_result field_tyvars) field_dict_ids -- We pull the field lambdas to the top, so we need to @@ -548,12 +635,12 @@ mkRecordSelId tycon field_label -- foo = /\a. \t:T. case t of { MkT f -> f a } mk_alt data_con - = ASSERT2( res_ty `tcEqType` field_ty, ppr data_con $$ ppr res_ty $$ ppr field_ty ) + = ASSERT2( data_ty `tcEqType` field_ty, ppr data_con $$ ppr data_ty $$ ppr field_ty ) mkReboxingAlt rebox_uniqs data_con (ex_tvs ++ co_tvs ++ arg_vs) rhs where -- get pattern binders with types appropriately instantiated arg_uniqs = map mkBuiltinUnique [arg_base..] - (ex_tvs, co_tvs, arg_vs) = dataConOrigInstPat arg_uniqs data_con res_tys + (ex_tvs, co_tvs, arg_vs) = dataConOrigInstPat arg_uniqs data_con scrut_ty_args rebox_base = arg_base + length ex_tvs + length co_tvs + length arg_vs rebox_uniqs = map mkBuiltinUnique [rebox_base..] @@ -565,14 +652,14 @@ mkRecordSelId tycon field_label -- T1 b' (c : [b]=[b']) (x:Maybe b') -- -> x `cast` Maybe (sym (right c)) - Succeeded refinement = gadtRefine emptyRefinement ex_tvs co_tvs - (co_fn, res_ty) = refineType refinement (idType the_arg_id) + -- Generate the refinement for b'=b, -- and apply to (Maybe b'), to get (Maybe b) - - rhs = case co_fn of - ExprCoFn co -> Cast (Var the_arg_id) co - id_co -> ASSERT(isIdCoercion id_co) Var the_arg_id + Succeeded refinement = gadtRefine emptyRefinement ex_tvs co_tvs + the_arg_id_ty = idType the_arg_id + (rhs, data_ty) = case refineType refinement the_arg_id_ty of + Just (co, data_ty) -> (Cast (Var the_arg_id) co, data_ty) + Nothing -> (Var the_arg_id, the_arg_id_ty) field_vs = filter (not . isPredTy . idType) arg_vs the_arg_id = assoc "mkRecordSelId:mk_alt" (field_lbls `zip` field_vs) field_label @@ -592,7 +679,7 @@ mkRecordSelId tycon field_label -- If we have e = MkT (MkS (PairInt 0 1)) and some body expecting a list of -- ids, we get (modulo int passing) -- --- case (e `cast` (sym CoT)) `cast` (sym CoS) of +-- case (e `cast` CoT) `cast` CoS of -- PairInt a b -> body [a,b] -- -- The Ints passed around are just for creating fresh locals @@ -745,7 +832,7 @@ mkDictSelId name clas -- C a -> C a -- for a single-op class (after all, the selector is the identity) -- But it's type must expose the representation of the dictionary - -- to gat (say) C a -> (a -> a) + -- to get (say) C a -> (a -> a) info = noCafIdInfo `setArityInfo` 1 @@ -767,45 +854,92 @@ mkDictSelId name clas tycon = classTyCon clas [data_con] = tyConDataCons tycon tyvars = dataConUnivTyVars data_con - arg_tys = ASSERT( isVanillaDataCon data_con ) dataConRepArgTys data_con + arg_tys = {- ASSERT( isVanillaDataCon data_con ) -} dataConRepArgTys data_con + eq_theta = dataConEqTheta data_con the_arg_id = assoc "MkId.mkDictSelId" (map idName (classSelIds clas) `zip` arg_ids) name - pred = mkClassPred clas (mkTyVarTys tyvars) - (dict_id:arg_ids) = mkTemplateLocals (mkPredTy pred : arg_tys) + pred = mkClassPred clas (mkTyVarTys tyvars) + dict_id = mkTemplateLocal 1 $ mkPredTy pred + (eq_ids,n) = mkCoVarLocals 2 $ mkPredTys eq_theta + arg_ids = mkTemplateLocalsNum n arg_tys + + mkCoVarLocals i [] = ([],i) + mkCoVarLocals i (x:xs) = let (ys,j) = mkCoVarLocals (i+1) xs + y = mkCoVar (mkSysTvName (mkBuiltinUnique i) FSLIT("dc_co")) x + in (y:ys,j) - rhs = mkLams tyvars (Lam dict_id rhs_body) + rhs = mkLams tyvars (Lam dict_id rhs_body) rhs_body | isNewTyCon tycon = unwrapNewTypeBody tycon (map mkTyVarTy tyvars) (Var dict_id) | otherwise = Case (Var dict_id) dict_id (idType the_arg_id) - [(DataAlt data_con, arg_ids, Var the_arg_id)] + [(DataAlt data_con, eq_ids ++ arg_ids, Var the_arg_id)] +\end{code} + + +%************************************************************************ +%* * + Wrapping and unwrapping newtypes and type families +%* * +%************************************************************************ +\begin{code} wrapNewTypeBody :: TyCon -> [Type] -> CoreExpr -> CoreExpr -- The wrapper for the data constructor for a newtype looks like this: -- newtype T a = MkT (a,Int) -- MkT :: forall a. (a,Int) -> T a --- MkT = /\a. \(x:(a,Int)). x `cast` CoT a +-- MkT = /\a. \(x:(a,Int)). x `cast` sym (CoT a) -- where CoT is the coercion TyCon assoicated with the newtype -- -- The call (wrapNewTypeBody T [a] e) returns the -- body of the wrapper, namely --- e `cast` CoT [a] +-- e `cast` (CoT [a]) -- --- If a coercion constructor is prodivided in the newtype, then we use +-- If a coercion constructor is provided in the newtype, then we use -- it, otherwise the wrap/unwrap are both no-ops -- +-- If the we are dealing with a newtype *instance*, we have a second coercion +-- identifying the family instance with the constructor of the newtype +-- instance. This coercion is applied in any case (ie, composed with the +-- coercion constructor of the newtype or applied by itself). + wrapNewTypeBody tycon args result_expr - | Just co_con <- newTyConCo tycon - = Cast result_expr (mkTyConApp co_con args) - | otherwise - = result_expr + = wrapFamInstBody tycon args inner + where + inner + | Just co_con <- newTyConCo_maybe tycon + = mkCoerce (mkSymCoercion (mkTyConApp co_con args)) result_expr + | otherwise + = result_expr + +-- When unwrapping, we do *not* apply any family coercion, because this will +-- be done via a CoPat by the type checker. We have to do it this way as +-- computing the right type arguments for the coercion requires more than just +-- a spliting operation (cf, TcPat.tcConPat). unwrapNewTypeBody :: TyCon -> [Type] -> CoreExpr -> CoreExpr unwrapNewTypeBody tycon args result_expr - | Just co_con <- newTyConCo tycon - = Cast result_expr (mkSymCoercion (mkTyConApp co_con args)) + | Just co_con <- newTyConCo_maybe tycon + = mkCoerce (mkTyConApp co_con args) result_expr | otherwise = result_expr +-- If the type constructor is a representation type of a data instance, wrap +-- the expression into a cast adjusting the expression type, which is an +-- instance of the representation type, to the corresponding instance of the +-- family instance type. +-- See Note [Wrappers for data instance tycons] +wrapFamInstBody :: TyCon -> [Type] -> CoreExpr -> CoreExpr +wrapFamInstBody tycon args body + | Just co_con <- tyConFamilyCoercion_maybe tycon + = mkCoerce (mkSymCoercion (mkTyConApp co_con args)) body + | otherwise + = body +unwrapFamInstScrut :: TyCon -> [Type] -> CoreExpr -> CoreExpr +unwrapFamInstScrut tycon args scrut + | Just co_con <- tyConFamilyCoercion_maybe tycon + = mkCoerce (mkTyConApp co_con args) scrut + | otherwise + = scrut \end{code} @@ -824,7 +958,7 @@ mkPrimOpId prim_op ty = mkForAllTys tyvars (mkFunTys arg_tys res_ty) name = mkWiredInName gHC_PRIM (primOpOcc prim_op) (mkPrimOpIdUnique (primOpTag prim_op)) - Nothing (AnId id) UserSyntax + (AnId id) UserSyntax id = mkGlobalId (PrimOpId prim_op) name ty info info = noCafIdInfo @@ -862,6 +996,29 @@ mkFCallId uniq fcall ty (arg_tys, _) = tcSplitFunTys tau arity = length arg_tys strict_sig = mkStrictSig (mkTopDmdType (replicate arity evalDmd) TopRes) + +-- Tick boxes and breakpoints are both represented as TickBoxOpIds, +-- except for the type: +-- +-- a plain HPC tick box has type (State# RealWorld) +-- a breakpoint Id has type forall a.a +-- +-- The breakpoint Id will be applied to a list of arbitrary free variables, +-- which is why it needs a polymorphic type. + +mkTickBoxOpId :: Unique -> Module -> TickBoxId -> Id +mkTickBoxOpId uniq mod ix = mkTickBox' uniq mod ix realWorldStatePrimTy + +mkBreakPointOpId :: Unique -> Module -> TickBoxId -> Id +mkBreakPointOpId uniq mod ix = mkTickBox' uniq mod ix ty + where ty = mkSigmaTy [openAlphaTyVar] [] openAlphaTy + +mkTickBox' uniq mod ix ty = mkGlobalId (TickBoxOpId tickbox) name ty info + where + tickbox = TickBox mod ix + occ_str = showSDoc (braces (ppr tickbox)) + name = mkTickBoxOpName uniq occ_str + info = noCafIdInfo \end{code} @@ -963,7 +1120,7 @@ another gun with which to shoot yourself in the foot. \begin{code} mkWiredInIdName mod fs uniq id - = mkWiredInName mod (mkOccNameFS varName fs) uniq Nothing (AnId id) UserSyntax + = mkWiredInName mod (mkOccNameFS varName fs) uniq (AnId id) UserSyntax unsafeCoerceName = mkWiredInIdName gHC_PRIM FSLIT("unsafeCoerce#") unsafeCoerceIdKey unsafeCoerceId nullAddrName = mkWiredInIdName gHC_PRIM FSLIT("nullAddr#") nullAddrIdKey nullAddrId @@ -996,8 +1153,7 @@ unsafeCoerceId (mkFunTy openAlphaTy openBetaTy) [x] = mkTemplateLocals [openAlphaTy] rhs = mkLams [openAlphaTyVar,openBetaTyVar,x] $ --- Note (Coerce openBetaTy openAlphaTy) (Var x) - Cast (Var x) (mkUnsafeCoercion openAlphaTy openBetaTy) + Cast (Var x) (mkUnsafeCoercion openAlphaTy openBetaTy) -- nullAddr# :: Addr# -- The reason is is here is because we don't provide @@ -1026,7 +1182,7 @@ seqId -- not from GHC.Base.hi. This is important, because the strictness -- analyser will spot it as strict! -- --- Also no unfolding in lazyId: it gets "inlined" by a HACK in the worker/wrapper pass +-- Also no unfolding in lazyId: it gets "inlined" by a HACK in the worker/wrapperpass -- (see WorkWrap.wwExpr) -- We could use inline phases to do this, but that would be vulnerable to changes in -- phase numbering....we must inline precisely after strictness analysis. @@ -1155,9 +1311,5 @@ pc_bottoming_Id name ty strict_sig = mkStrictSig (mkTopDmdType [evalDmd] BotRes) -- These "bottom" out, no matter what their arguments - -(openAlphaTyVar:openBetaTyVar:_) = openAlphaTyVars -openAlphaTy = mkTyVarTy openAlphaTyVar -openBetaTy = mkTyVarTy openBetaTyVar \end{code}