X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FbasicTypes%2FMkId.lhs;h=c112a2ab0e2a9f3da88a009885325a47689e3a47;hb=53ce311e219dcccf4d205f573c16e23a5c44265e;hp=c2809e3e9fb85a3b3eb0ae82588f9e7c86bdcf65;hpb=44d91e4c577768d4c19a699e326aa50aefc3b4cb;p=ghc-hetmet.git diff --git a/ghc/compiler/basicTypes/MkId.lhs b/ghc/compiler/basicTypes/MkId.lhs index c2809e3..c112a2a 100644 --- a/ghc/compiler/basicTypes/MkId.lhs +++ b/ghc/compiler/basicTypes/MkId.lhs @@ -17,13 +17,13 @@ module MkId ( mkDictSelId, mkDataConId, mkDataConWrapId, - mkRecordSelId, - mkPrimOpId, mkCCallOpId, + mkRecordSelId, rebuildConArgs, + mkPrimOpId, mkFCallId, -- And some particular Ids; see below for why they are wired in wiredInIds, - unsafeCoerceId, realWorldPrimId, - eRROR_ID, rEC_SEL_ERROR_ID, pAT_ERROR_ID, rEC_CON_ERROR_ID, + unsafeCoerceId, realWorldPrimId, voidArgId, nullAddrId, + eRROR_ID, eRROR_CSTRING_ID, rEC_SEL_ERROR_ID, pAT_ERROR_ID, rEC_CON_ERROR_ID, rEC_UPD_ERROR_ID, iRREFUT_PAT_ERROR_ID, nON_EXHAUSTIVE_GUARDS_ERROR_ID, nO_METHOD_BINDING_ERROR_ID, aBSENT_ERROR_ID, pAR_ERROR_ID ) where @@ -31,61 +31,63 @@ module MkId ( #include "HsVersions.h" -import BasicTypes ( Arity ) -import TysPrim ( openAlphaTyVars, alphaTyVar, alphaTy, - intPrimTy, realWorldStatePrimTy +import BasicTypes ( Arity, StrictnessMark(..), isMarkedUnboxed, isMarkedStrict ) +import TysPrim ( openAlphaTyVars, alphaTyVar, alphaTy, betaTyVar, betaTy, + intPrimTy, realWorldStatePrimTy, addrPrimTy ) import TysWiredIn ( charTy, mkListTy ) -import PrelNames ( pREL_ERR, pREL_GHC ) -import PrelRules ( primOpRule ) +import PrelRules ( primOpRules ) import Rules ( addRule ) -import Type ( Type, ThetaType, mkDictTy, mkPredTys, mkTyConApp, mkTyVarTys, - mkFunTys, mkFunTy, mkSigmaTy, splitSigmaTy, +import TcType ( Type, ThetaType, mkDictTy, mkPredTys, mkTyConApp, + mkTyVarTys, mkClassPred, tcEqPred, + mkFunTys, mkFunTy, mkSigmaTy, tcSplitSigmaTy, isUnLiftedType, mkForAllTys, mkTyVarTy, tyVarsOfType, - splitFunTys, splitForAllTys, mkPredTy + tcSplitFunTys, tcSplitForAllTys, mkPredTy ) import Module ( Module ) -import CoreUtils ( exprType, mkInlineMe ) +import CoreUtils ( exprType ) import CoreUnfold ( mkTopUnfolding, mkCompulsoryUnfolding, mkOtherCon ) -import Literal ( Literal(..) ) +import Literal ( Literal(..), nullAddrLit ) import TyCon ( TyCon, isNewTyCon, tyConTyVars, tyConDataCons, - tyConTheta, isProductTyCon, isDataTyCon ) + tyConTheta, isProductTyCon, isDataTyCon, isRecursiveTyCon ) import Class ( Class, classTyCon, classTyVars, classSelIds ) import Var ( Id, TyVar ) import VarSet ( isEmptyVarSet ) -import Name ( mkWiredInName, mkCCallName, Name ) +import Name ( mkWiredInName, mkFCallName, Name ) import OccName ( mkVarOcc ) -import PrimOp ( PrimOp(DataToTagOp, CCallOp), - primOpSig, mkPrimOpIdName, - CCall, pprCCallOp - ) -import Demand ( wwStrict, wwPrim, mkStrictnessInfo ) -import DataCon ( DataCon, StrictnessMark(..), +import PrimOp ( PrimOp(DataToTagOp), primOpSig, mkPrimOpIdName ) +import ForeignCall ( ForeignCall ) +import DataCon ( DataCon, dataConFieldLabels, dataConRepArity, dataConTyCon, - dataConArgTys, dataConRepType, dataConRepStrictness, + dataConArgTys, dataConRepType, dataConInstOrigArgTys, dataConName, dataConTheta, dataConSig, dataConStrictMarks, dataConId, - maybeMarkedUnboxed, splitProductType_maybe + splitProductType ) -import Id ( idType, mkGlobalId, mkVanillaGlobal, +import Id ( idType, mkGlobalId, mkVanillaGlobal, mkSysLocal, mkTemplateLocals, mkTemplateLocalsNum, - mkTemplateLocal, idCprInfo + mkTemplateLocal, idNewStrictness, idName ) import IdInfo ( IdInfo, noCafNoTyGenIdInfo, - exactArity, setUnfoldingInfo, setCprInfo, - setArityInfo, setSpecInfo, setCgInfo, - mkStrictnessInfo, setStrictnessInfo, - GlobalIdDetails(..), CafInfo(..), CprInfo(..), - CgInfo(..), setCgArity + setUnfoldingInfo, + setArityInfo, setSpecInfo, setCafInfo, + newStrictnessFromOld, setAllStrictnessInfo, + GlobalIdDetails(..), CafInfo(..), CprInfo(..) ) +import NewDemand ( mkStrictSig, strictSigResInfo, DmdResult(..), + mkTopDmdType, topDmd, evalDmd, lazyDmd, + Demand(..), Demands(..) ) import FieldLabel ( mkFieldLabel, fieldLabelName, firstFieldLabelTag, allFieldLabelTags, fieldLabelType ) +import DmdAnal ( dmdAnalTopRhs ) import CoreSyn +import Unique ( mkBuiltinUnique ) import Maybes import PrelNames import Maybe ( isJust ) +import Util ( dropList, isSingleton ) import Outputable import ListSetOps ( assoc, assocMaybe ) import UnicodeUtil ( stringToUtf8 ) @@ -106,11 +108,12 @@ wiredInIds -- -- [The interface file format now carry such information, but there's -- no way yet of expressing at the definition site for these - -- error-reporting - -- functions that they have an 'open' result type. -- sof 1/99] + -- error-reporting functions that they have an 'open' + -- result type. -- sof 1/99] aBSENT_ERROR_ID , eRROR_ID + , eRROR_CSTRING_ID , iRREFUT_PAT_ERROR_ID , nON_EXHAUSTIVE_GUARDS_ERROR_ID , nO_METHOD_BINDING_ERROR_ID @@ -119,10 +122,13 @@ wiredInIds , rEC_CON_ERROR_ID , rEC_UPD_ERROR_ID - -- These three can't be defined in Haskell + -- These can't be defined in Haskell, but they have + -- perfectly reasonable unfoldings in Core , realWorldPrimId , unsafeCoerceId + , nullAddrId , getTagId + , seqId ] \end{code} @@ -140,23 +146,36 @@ mkDataConId work_name data_con = mkGlobalId (DataConId data_con) work_name (dataConRepType data_con) info where info = noCafNoTyGenIdInfo - `setCgArity` arity - `setArityInfo` exactArity arity - `setStrictnessInfo` strict_info - `setCprInfo` cpr_info - - arity = dataConRepArity data_con - - strict_info = mkStrictnessInfo (dataConRepStrictness data_con, False) + `setArityInfo` arity + `setAllStrictnessInfo` Just strict_sig + + arity = dataConRepArity data_con + + strict_sig = mkStrictSig (mkTopDmdType (replicate arity topDmd) cpr_info) + -- 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) + -- Why? Because the *wrapper* is strict (and its unfolding has case + -- expresssions that do the evals) but the *worker* itself is not. + -- If we pretend it is strict then when we see + -- case x of y -> $wMkT y + -- the simplifier thinks that y is "sure to be evaluated" (because + -- $wMkT is strict) and drops the case. No, $wMkT is not strict. + -- + -- When the simplifer sees a pattern + -- case e of MkT x -> ... + -- it uses the dataConRepStrictness of MkT to mark x as evaluated; + -- but that's fine... dataConRepStrictness comes from the data con + -- not from the worker Id. tycon = dataConTyCon data_con cpr_info | isProductTyCon tycon && isDataTyCon tycon && arity > 0 && - arity <= mAX_CPR_SIZE = ReturnsCPR - | otherwise = NoCPRInfo - -- ReturnsCPR is only true for products that are real data types; - -- that is, not unboxed tuples or newtypes + arity <= mAX_CPR_SIZE = RetCPR + | otherwise = TopRes + -- RetCPR is only true for products that are real data types; + -- that is, not unboxed tuples or [non-recursive] newtypes mAX_CPR_SIZE :: Arity mAX_CPR_SIZE = 10 @@ -209,57 +228,64 @@ Notice that \begin{code} mkDataConWrapId data_con - = wrap_id + = mkGlobalId (DataConWrapId data_con) (dataConName data_con) wrap_ty info where - wrap_id = mkGlobalId (DataConWrapId data_con) (dataConName data_con) wrap_ty info work_id = dataConId data_con info = noCafNoTyGenIdInfo - `setUnfoldingInfo` mkTopUnfolding (mkInlineMe wrap_rhs) - `setCprInfo` cpr_info - -- The Cpr info can be important inside INLINE rhss, where the - -- wrapper constructor isn't inlined - `setCgArity` arity + `setUnfoldingInfo` wrap_unf -- The NoCaf-ness is set by noCafNoTyGenIdInfo - `setArityInfo` exactArity arity + `setArityInfo` arity -- It's important to specify the arity, so that partial -- applications are treated as values - - wrap_ty = mkForAllTys all_tyvars $ - mkFunTys all_arg_tys - result_ty - - cpr_info = idCprInfo work_id - - wrap_rhs | isNewTyCon tycon - = ASSERT( null ex_tyvars && null ex_dict_args && length orig_arg_tys == 1 ) + `setAllStrictnessInfo` Just wrap_sig + + wrap_ty = mkForAllTys all_tyvars (mkFunTys all_arg_tys result_ty) + + wrap_sig = mkStrictSig (mkTopDmdType arg_dmds res_info) + res_info = strictSigResInfo (idNewStrictness work_id) + arg_dmds = [Abs | d <- dict_args] ++ map mk_dmd strict_marks + mk_dmd str | isMarkedStrict str = evalDmd + | otherwise = lazyDmd + -- The Cpr info can be important inside INLINE rhss, where the + -- wrapper constructor isn't inlined. + -- And the argument strictness can be important too; we + -- may not inline a contructor when it is partially applied. + -- For example: + -- data W = C !Int !Int !Int + -- ...(let w = C x in ...(w p q)...)... + -- we want to see that w is strict in its two arguments + + wrap_unf | isNewTyCon tycon + = ASSERT( null ex_tyvars && null ex_dict_args && isSingleton orig_arg_tys ) -- No existentials on a newtype, but it can have a context -- e.g. newtype Eq a => T a = MkT (...) - - mkLams tyvars $ mkLams dict_args $ Lam id_arg1 $ - Note (Coerce result_ty (head orig_arg_tys)) (Var id_arg1) - - | null dict_args && all not_marked_strict strict_marks - = Var work_id -- The common case. Not only is this efficient, - -- but it also ensures that the wrapper is replaced - -- by the worker even when there are no args. - -- f (:) x - -- becomes - -- f $w: x - -- This is really important in rule matching, - -- (We could match on the wrappers, - -- but that makes it less likely that rules will match - -- when we bring bits of unfoldings together.) + mkTopUnfolding $ Note InlineMe $ + mkLams tyvars $ mkLams dict_args $ Lam id_arg1 $ + mkNewTypeBody tycon result_ty (Var id_arg1) + + | null dict_args && not (any isMarkedStrict strict_marks) + = mkCompulsoryUnfolding (Var work_id) + -- The common case. Not only is this efficient, + -- but it also ensures that the wrapper is replaced + -- by the worker even when there are no args. + -- f (:) x + -- becomes + -- f $w: x + -- This is really important in rule matching, + -- (We could match on the wrappers, + -- but that makes it less likely that rules will match + -- when we bring bits of unfoldings together.) -- -- NB: because of this special case, (map (:) ys) turns into - -- (map $w: ys), and thence into (map (\x xs. $w: x xs) ys) - -- in core-to-stg. The top-level defn for (:) is never used. + -- (map $w: ys). The top-level defn for (:) is never used. -- This is somewhat of a bore, but I'm currently leaving it -- as is, so that there still is a top level curried (:) for -- the interpreter to call. | otherwise - = mkLams all_tyvars $ mkLams dict_args $ + = mkTopUnfolding $ Note InlineMe $ + mkLams all_tyvars $ mkLams dict_args $ mkLams ex_dict_args $ mkLams id_args $ foldr mk_case con_app (zip (ex_dict_args++id_args) strict_marks) i3 [] @@ -286,15 +312,12 @@ mkDataConWrapId data_con (id_arg1:_) = id_args -- Used for newtype only strict_marks = dataConStrictMarks data_con - not_marked_strict NotMarkedStrict = True - not_marked_strict other = False - mk_case - :: (Id, StrictnessMark) -- arg, strictness - -> (Int -> [Id] -> CoreExpr) -- body - -> Int -- next rep arg id - -> [Id] -- rep args so far + :: (Id, StrictnessMark) -- Arg, strictness + -> (Int -> [Id] -> CoreExpr) -- Body + -> Int -- Next rep arg id + -> [Id] -- Rep args so far, reversed -> CoreExpr mk_case (arg,strict) body i rep_args = case strict of @@ -304,11 +327,13 @@ mkDataConWrapId data_con | otherwise -> Case (Var arg) arg [(DEFAULT,[], body i (arg:rep_args))] - MarkedUnboxed con tys -> - Case (Var arg) arg [(DataAlt con, con_args, - body i' (reverse con_args++rep_args))] - where - (con_args,i') = mkLocals i tys + MarkedUnboxed + -> case splitProductType "do_unbox" (idType arg) of + (tycon, tycon_args, con, tys) -> + Case (Var arg) arg [(DataAlt con, con_args, + body i' (reverse con_args ++ rep_args))] + where + (con_args, i') = mkLocals i tys \end{code} @@ -376,11 +401,11 @@ mkRecordSelId tycon field_label unpack_id unpackUtf8_id -- eg data (Eq a, Ord b) => T a b = ... dict_tys = [mkPredTy pred | pred <- tycon_theta, needed_dict pred] - needed_dict pred = or [ pred `elem` (dataConTheta dc) - | (DataAlt dc, _, _) <- the_alts] + needed_dict pred = or [ tcEqPred pred p + | (DataAlt dc, _, _) <- the_alts, p <- dataConTheta dc] n_dict_tys = length dict_tys - (field_tyvars,field_theta,field_tau) = splitSigmaTy field_ty + (field_tyvars,field_theta,field_tau) = tcSplitSigmaTy field_ty field_dict_tys = map mkPredTy field_theta n_field_dict_tys = length field_dict_tys -- If the field has a universally quantified type we have to @@ -410,13 +435,16 @@ mkRecordSelId tycon field_label unpack_id unpackUtf8_id mkFunTy data_ty field_tau arity = 1 + n_dict_tys + n_field_dict_tys - info = noCafNoTyGenIdInfo - `setCgInfo` (CgInfo arity caf_info) - `setArityInfo` exactArity arity - `setUnfoldingInfo` unfolding - -- ToDo: consider adding further IdInfo - unfolding = mkTopUnfolding sel_rhs + (strict_sig, rhs_w_str) = dmdAnalTopRhs sel_rhs + -- Use the demand analyser to work out strictness. + -- With all this unpackery it's not easy! + + info = noCafNoTyGenIdInfo + `setCafInfo` caf_info + `setArityInfo` arity + `setUnfoldingInfo` mkTopUnfolding rhs_w_str + `setAllStrictnessInfo` Just strict_sig -- Allocate Ids. We do it a funny way round because field_dict_tys is -- almost always empty. Also note that we use length_tycon_theta @@ -445,20 +473,31 @@ mkRecordSelId tycon field_label unpack_id unpackUtf8_id mkLams dict_ids $ mkLams field_dict_ids $ Lam data_id $ sel_body - sel_body | isNewTyCon tycon = Note (Coerce field_tau data_ty) (Var data_id) - | otherwise = Case (Var data_id) data_id (the_alts ++ default_alt) + sel_body | isNewTyCon tycon = mkNewTypeBody tycon field_tau (mk_result data_id) + | otherwise = Case (Var data_id) data_id (default_alt ++ the_alts) + + mk_result result_id = mkVarApps (mkVarApps (Var result_id) field_tyvars) field_dict_ids + -- We pull the field lambdas to the top, so we need to + -- apply them in the body. For example: + -- data T = MkT { foo :: forall a. a->a } + -- + -- foo :: forall a. T -> a -> a + -- foo = /\a. \t:T. case t of { MkT f -> f a } mk_maybe_alt data_con = case maybe_the_arg_id of Nothing -> Nothing - Just the_arg_id -> Just (DataAlt data_con, real_args, expr) + Just the_arg_id -> Just (DataAlt data_con, real_args, mkLets binds body) where - body = mkVarApps (mkVarApps (Var the_arg_id) field_tyvars) field_dict_ids - strict_marks = dataConStrictMarks data_con - (expr, real_args) = rebuildConArgs data_con arg_ids strict_marks body - (length arg_ids + 1) + body = mk_result the_arg_id + strict_marks = dataConStrictMarks data_con + (binds, real_args) = rebuildConArgs arg_ids strict_marks + (map mkBuiltinUnique [unpack_base..]) where arg_ids = mkTemplateLocalsNum field_base (dataConInstOrigArgTys data_con tyvar_tys) + + unpack_base = field_base + length arg_ids + -- arity+1 avoids all shadowing maybe_the_arg_id = assocMaybe (field_lbls `zip` arg_ids) field_label field_lbls = dataConFieldLabels data_con @@ -477,41 +516,46 @@ mkRecordSelId tycon field_label unpack_id unpackUtf8_id full_msg = showSDoc (sep [text "No match in record selector", ppr sel_id]) --- this rather ugly function converts the unpacked data con arguments back into --- their packed form. It is almost the same as the version in DsUtils, except that --- we use template locals here rather than newDsId (ToDo: merge these). +-- This rather ugly function converts the unpacked data con +-- arguments back into their packed form. rebuildConArgs - :: DataCon -- the con we're matching on - -> [Id] -- the source-level args - -> [StrictnessMark] -- the strictness annotations (per-arg) - -> CoreExpr -- the body - -> Int -- template local - -> (CoreExpr, [Id]) - -rebuildConArgs con [] stricts body i = (body, []) -rebuildConArgs con (arg:args) stricts body i | isTyVar arg - = let (body', args') = rebuildConArgs con args stricts body i - in (body',arg:args') -rebuildConArgs con (arg:args) (str:stricts) body i - = case maybeMarkedUnboxed str of - Just (pack_con1, _) -> - case splitProductType_maybe (idType arg) of - Just (_, tycon_args, pack_con, con_arg_tys) -> - ASSERT( pack_con == pack_con1 ) - let unpacked_args = zipWith mkTemplateLocal [i..] con_arg_tys - (body', real_args) = rebuildConArgs con args stricts body - (i + length con_arg_tys) - in - ( - Let (NonRec arg (mkConApp pack_con - (map Type tycon_args ++ - map Var unpacked_args))) body', - unpacked_args ++ real_args - ) - - _ -> let (body', args') = rebuildConArgs con args stricts body i - in (body', arg:args') + :: [Id] -- Source-level args + -> [StrictnessMark] -- Strictness annotations (per-arg) + -> [Unique] -- Uniques for the new Ids + -> ([CoreBind], [Id]) -- A binding for each source-level arg, plus + -- a list of the representation-level arguments +-- e.g. data T = MkT Int !Int +-- +-- rebuild [x::Int, y::Int] [Not, Unbox] +-- = ([ y = I# t ], [x,t]) + +rebuildConArgs [] stricts us = ([], []) + +-- Type variable case +rebuildConArgs (arg:args) stricts us + | isTyVar arg + = let (binds, args') = rebuildConArgs args stricts us + in (binds, arg:args') + +-- Term variable case +rebuildConArgs (arg:args) (str:stricts) us + | isMarkedUnboxed str + = let + arg_ty = idType arg + + (_, tycon_args, pack_con, con_arg_tys) + = splitProductType "rebuildConArgs" arg_ty + + unpacked_args = zipWith (mkSysLocal SLIT("rb")) us con_arg_tys + (binds, args') = rebuildConArgs args stricts (dropList con_arg_tys us) + con_app = mkConApp pack_con (map Type tycon_args ++ map Var unpacked_args) + in + (NonRec arg con_app : binds, unpacked_args ++ args') + + | otherwise + = let (binds, args') = rebuildConArgs args stricts us + in (binds, arg:args') \end{code} @@ -529,22 +573,34 @@ ToDo: unify with mkRecordSelId. \begin{code} mkDictSelId :: Name -> Class -> Id mkDictSelId name clas - = sel_id + = mkGlobalId (RecordSelId field_lbl) name sel_ty info where - ty = exprType rhs - sel_id = mkGlobalId (RecordSelId field_lbl) name ty info - field_lbl = mkFieldLabel name tycon ty tag - tag = assoc "MkId.mkDictSelId" (classSelIds clas `zip` allFieldLabelTags) sel_id + sel_ty = mkForAllTys tyvars (mkFunTy (idType dict_id) (idType the_arg_id)) + -- We can't just say (exprType rhs), because that would give a type + -- 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) + + field_lbl = mkFieldLabel name tycon sel_ty tag + tag = assoc "MkId.mkDictSelId" (map idName (classSelIds clas) `zip` allFieldLabelTags) name info = noCafNoTyGenIdInfo - `setCgArity` 1 - `setArityInfo` exactArity 1 - `setUnfoldingInfo` unfolding - + `setArityInfo` 1 + `setUnfoldingInfo` mkTopUnfolding rhs + `setAllStrictnessInfo` Just strict_sig + -- We no longer use 'must-inline' on record selectors. They'll -- inline like crazy if they scrutinise a constructor - unfolding = mkTopUnfolding rhs + -- The strictness signature is of the form U(AAAVAAAA) -> T + -- where the V depends on which item we are selecting + -- It's worth giving one, so that absence info etc is generated + -- even if the selector isn't inlined + strict_sig = mkStrictSig (mkTopDmdType [arg_dmd] TopRes) + arg_dmd | isNewTyCon tycon = evalDmd + | otherwise = Eval (Prod [ if the_arg_id == id then evalDmd else Abs + | id <- arg_ids ]) tyvars = classTyVars clas @@ -554,14 +610,22 @@ mkDictSelId name clas arg_tys = dataConArgTys data_con tyvar_tys the_arg_id = arg_ids !! (tag - firstFieldLabelTag) - dict_ty = mkDictTy clas tyvar_tys - (dict_id:arg_ids) = mkTemplateLocals (dict_ty : arg_tys) + pred = mkClassPred clas tyvar_tys + (dict_id:arg_ids) = mkTemplateLocals (mkPredTy pred : arg_tys) - rhs | isNewTyCon tycon = mkLams tyvars $ Lam dict_id $ - Note (Coerce (head arg_tys) dict_ty) (Var dict_id) + rhs | isNewTyCon tycon = mkLams tyvars $ Lam dict_id $ + mkNewTypeBody tycon (head arg_tys) (Var dict_id) | otherwise = mkLams tyvars $ Lam dict_id $ Case (Var dict_id) dict_id [(DataAlt data_con, arg_ids, Var the_arg_id)] + +mkNewTypeBody tycon result_ty result_expr + -- Adds a coerce where necessary + -- Used for both wrapping and unwrapping + | isRecursiveTyCon tycon -- Recursive case; use a coerce + = Note (Coerce result_ty (exprType result_expr)) result_expr + | otherwise -- Normal case + = result_expr \end{code} @@ -583,12 +647,11 @@ mkPrimOpId prim_op info = noCafNoTyGenIdInfo `setSpecInfo` rules - `setCgArity` arity - `setArityInfo` exactArity arity - `setStrictnessInfo` strict_info + `setArityInfo` arity + `setAllStrictnessInfo` Just (newStrictnessFromOld name arity strict_info NoCPRInfo) + -- Until we modify the primop generation code - rules = maybe emptyCoreRules (addRule emptyCoreRules id) - (primOpRule prim_op) + rules = foldl (addRule id) emptyCoreRules (primOpRules prim_op) -- For each ccall we manufacture a separate CCallOpId, giving it @@ -600,29 +663,27 @@ mkPrimOpId prim_op -- details of the ccall, type and all. This means that the interface -- file reader can reconstruct a suitable Id -mkCCallOpId :: Unique -> CCall -> Type -> Id -mkCCallOpId uniq ccall ty +mkFCallId :: Unique -> ForeignCall -> Type -> Id +mkFCallId uniq fcall ty = ASSERT( isEmptyVarSet (tyVarsOfType ty) ) -- A CCallOpId should have no free type variables; -- when doing substitutions won't substitute over it - mkGlobalId (PrimOpId prim_op) name ty info + mkGlobalId (FCallId fcall) name ty info where - occ_str = showSDocIface (braces (pprCCallOp ccall <+> ppr ty)) + occ_str = showSDocIface (braces (ppr fcall <+> ppr ty)) -- The "occurrence name" of a ccall is the full info about the -- ccall; it is encoded, but may have embedded spaces etc! - name = mkCCallName uniq occ_str - prim_op = CCallOp ccall + name = mkFCallName uniq occ_str info = noCafNoTyGenIdInfo - `setCgArity` arity - `setArityInfo` exactArity arity - `setStrictnessInfo` strict_info + `setArityInfo` arity + `setAllStrictnessInfo` Just strict_sig - (_, tau) = splitForAllTys ty - (arg_tys, _) = splitFunTys tau + (_, tau) = tcSplitForAllTys ty + (arg_tys, _) = tcSplitFunTys tau arity = length arg_tys - strict_info = mkStrictnessInfo (take arity (repeat wwPrim), False) + strict_sig = mkStrictSig (mkTopDmdType (replicate arity evalDmd) TopRes) \end{code} @@ -632,9 +693,34 @@ mkCCallOpId uniq ccall ty %* * %************************************************************************ +Important notes about dict funs and default methods +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +Dict funs and default methods are *not* ImplicitIds. Their definition +involves user-written code, so we can't figure out their strictness etc +based on fixed info, as we can for constructors and record selectors (say). + +We build them as GlobalIds, but when in the module where they are +bound, we turn the Id at the *binding site* into an exported LocalId. +This ensures that they are taken to account by free-variable finding +and dependency analysis (e.g. CoreFVs.exprFreeVars). The simplifier +will propagate the LocalId to all occurrence sites. + +Why shouldn't they be bound as GlobalIds? Because, in particular, if +they are globals, the specialiser floats dict uses above their defns, +which prevents good simplifications happening. Also the strictness +analyser treats a occurrence of a GlobalId as imported and assumes it +contains strictness in its IdInfo, which isn't true if the thing is +bound in the same module as the occurrence. + +It's OK for dfuns to be LocalIds, because we form the instance-env to +pass on to the next module (md_insts) in CoreTidy, afer tidying +and globalising the top-level Ids. + +BUT make sure they are *exported* LocalIds (setIdLocalExported) so +that they aren't discarded by the occurrence analyser. + \begin{code} -mkDefaultMethodId dm_name ty - = mkVanillaGlobal dm_name ty noCafNoTyGenIdInfo +mkDefaultMethodId dm_name ty = mkVanillaGlobal dm_name ty noCafNoTyGenIdInfo mkDictFunId :: Name -- Name to use for the dict fun; -> Class @@ -684,7 +770,12 @@ mkDictFunId dfun_name clas inst_tyvars inst_tys dfun_theta %* * %************************************************************************ -These two can't be defined in Haskell. +These Ids can't be defined in Haskell. They could be defined in +unfoldings in PrelGHC.hi-boot, but we'd have to ensure that they +were definitely, definitely inlined, because there is no curried +identifier for them. That's what mkCompulsoryUnfolding does. +If we had a way to get a compulsory unfolding from an interface file, +we could do that, but we don't right now. unsafeCoerce# isn't so much a PrimOp as a phantom identifier, that just gets expanded into a type coercion wherever it occurs. Hence we @@ -695,6 +786,7 @@ they can unify with both unlifted and lifted types. Hence we provide another gun with which to shoot yourself in the foot. \begin{code} +-- unsafeCoerce# :: forall a b. a -> b unsafeCoerceId = pcMiscPrelId unsafeCoerceIdKey pREL_GHC SLIT("unsafeCoerce#") ty info where @@ -706,8 +798,27 @@ unsafeCoerceId [x] = mkTemplateLocals [openAlphaTy] rhs = mkLams [openAlphaTyVar,openBetaTyVar,x] $ Note (Coerce openBetaTy openAlphaTy) (Var x) -\end{code} +-- nullAddr# :: Addr# +-- The reason is is here is because we don't provide +-- a way to write this literal in Haskell. +nullAddrId + = pcMiscPrelId nullAddrIdKey pREL_GHC SLIT("nullAddr#") addrPrimTy info + where + info = noCafNoTyGenIdInfo `setUnfoldingInfo` + mkCompulsoryUnfolding (Lit nullAddrLit) + +seqId + = pcMiscPrelId seqIdKey pREL_GHC SLIT("seq") ty info + where + info = noCafNoTyGenIdInfo `setUnfoldingInfo` mkCompulsoryUnfolding rhs + + + ty = mkForAllTys [alphaTyVar,betaTyVar] + (mkFunTy alphaTy (mkFunTy betaTy betaTy)) + [x,y] = mkTemplateLocals [alphaTy, betaTy] + rhs = mkLams [alphaTyVar,betaTyVar,x,y] (Case (Var x) x [(DEFAULT, [], Var y)]) +\end{code} @getTag#@ is another function which can't be defined in Haskell. It needs to evaluate its argument and call the dataToTag# primitive. @@ -730,6 +841,13 @@ dataToTagId = mkPrimOpId DataToTagOp @realWorld#@ used to be a magic literal, \tr{void#}. If things get nasty as-is, change it back to a literal (@Literal@). +voidArgId is a Local Id used simply as an argument in functions +where we just want an arg to avoid having a thunk of unlifted type. +E.g. + x = \ void :: State# RealWorld -> (# p, q #) + +This comes up in strictness analysis + \begin{code} realWorldPrimId -- :: State# RealWorld = pcMiscPrelId realWorldPrimIdKey pREL_GHC SLIT("realWorld#") @@ -739,6 +857,9 @@ realWorldPrimId -- :: State# RealWorld -- which in turn makes Simplify.interestingArg return True, -- which in turn makes INLINE things applied to realWorld# likely -- to be inlined + +voidArgId -- :: State# RealWorld + = mkSysLocal SLIT("void") voidArgIdKey realWorldStatePrimTy \end{code} @@ -766,6 +887,9 @@ templates, but we don't ever expect to generate code for it. \begin{code} eRROR_ID = pc_bottoming_Id errorIdKey pREL_ERR SLIT("error") errorTy +eRROR_CSTRING_ID + = pc_bottoming_Id errorCStringIdKey pREL_ERR SLIT("errorCString") + (mkSigmaTy [openAlphaTyVar] [] (mkFunTy addrPrimTy openAlphaTy)) pAT_ERROR_ID = generic_ERROR_ID patErrorIdKey SLIT("patError") rEC_SEL_ERROR_ID @@ -814,9 +938,8 @@ pcMiscPrelId key mod str ty info pc_bottoming_Id key mod name ty = pcMiscPrelId key mod name ty bottoming_info where - bottoming_info = noCafNoTyGenIdInfo - `setStrictnessInfo` mkStrictnessInfo ([wwStrict], True) - + strict_sig = mkStrictSig (mkTopDmdType [evalDmd] BotRes) + bottoming_info = noCafNoTyGenIdInfo `setAllStrictnessInfo` Just strict_sig -- these "bottom" out, no matter what their arguments generic_ERROR_ID u n = pc_bottoming_Id u pREL_ERR n errorTy