mkSpecPragmaId, mkWorkerId,
mkDictFunId, mkDefaultMethodId,
- mkMethodSelId, mkSuperDictSelId,
+ mkDictSelId,
- mkDataConId,
+ mkDataConId, mkDataConWrapId,
mkRecordSelId,
- mkNewTySelId,
- mkPrimitiveId
+ mkPrimOpId, mkCCallOpId,
+
+ -- 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,
+ 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
#include "HsVersions.h"
-import {-# SOURCE #-} CoreUnfold ( mkUnfolding )
-import TysWiredIn ( boolTy )
-import Type ( Type, ThetaType,
- mkDictTy, mkTyConApp, mkTyVarTys, mkFunTys, mkFunTy, mkSigmaTy,
- isUnLiftedType, substTopTheta,
- splitSigmaTy, splitFunTy_maybe, splitAlgTyConApp,
- splitFunTys, splitForAllTys
+import TysPrim ( openAlphaTyVars, alphaTyVar, alphaTy,
+ intPrimTy, realWorldStatePrimTy
)
-import TyCon ( TyCon, isNewTyCon, tyConDataCons, isDataTyCon )
-import Class ( Class, classBigSig, classTyCon )
-import Var ( Id, TyVar, VarDetails(..), mkId )
-import VarEnv ( zipVarEnv )
-import Const ( Con(..) )
-import Name ( mkDerivedName, mkWiredInIdName,
- mkWorkerOcc, mkSuperDictSelOcc,
+import TysWiredIn ( boolTy, charTy, mkListTy )
+import PrelNames ( pREL_ERR, pREL_GHC )
+import PrelRules ( primOpRule )
+import Rules ( addRule )
+import Type ( Type, ClassContext, mkDictTy, mkDictTys, mkTyConApp, mkTyVarTys,
+ mkFunTys, mkFunTy, mkSigmaTy, classesToPreds,
+ isUnLiftedType, mkForAllTys, mkTyVarTy, tyVarsOfType, tyVarsOfTypes,
+ splitSigmaTy, splitFunTy_maybe,
+ splitFunTys, splitForAllTys, unUsgTy,
+ mkUsgTy, UsageAnn(..)
+ )
+import PprType ( pprParendType )
+import Module ( Module )
+import CoreUtils ( exprType, mkInlineMe )
+import CoreUnfold ( mkTopUnfolding, mkCompulsoryUnfolding, mkOtherCon )
+import Literal ( Literal(..) )
+import Subst ( mkTopTyVarSubst, substClasses )
+import TyCon ( TyCon, isNewTyCon, tyConTyVars, tyConDataCons, isDataTyCon,
+ tyConTheta, isProductTyCon, isUnboxedTupleTyCon )
+import Class ( Class, classBigSig, classTyCon, classTyVars, classSelIds )
+import Var ( Id, TyVar )
+import VarSet ( isEmptyVarSet )
+import Name ( mkDerivedName, mkWiredInIdName, mkLocalName,
+ mkWorkerOcc, mkSuperDictSelOcc, mkCCallName,
Name, NamedThing(..),
)
-import PrimOp ( PrimOp, primOpType, primOpOcc, primOpUniq )
-import DataCon ( DataCon, dataConStrictMarks, dataConFieldLabels,
- dataConArgTys, dataConSig
+import OccName ( mkSrcVarOcc )
+import PrimOp ( PrimOp(DataToTagOp, CCallOp),
+ primOpSig, mkPrimOpIdName,
+ CCall, pprCCallOp
+ )
+import Demand ( wwStrict, wwPrim, mkStrictnessInfo )
+import DataCon ( DataCon, StrictnessMark(..),
+ dataConFieldLabels, dataConRepArity, dataConTyCon,
+ dataConArgTys, dataConRepType, dataConRepStrictness,
+ dataConName, dataConTheta,
+ dataConSig, dataConStrictMarks, dataConId
)
-import Id ( idType,
- mkUserLocal, mkVanillaId, mkTemplateLocals,
- setInlinePragma
+import Id ( idType, mkId,
+ mkVanillaId, mkTemplateLocals,
+ mkTemplateLocal, setInlinePragma, idCprInfo
)
-import IdInfo ( noIdInfo,
- exactArity, setUnfoldingInfo,
- setArityInfo, setInlinePragInfo,
- InlinePragInfo(..), IdInfo
+import IdInfo ( IdInfo, vanillaIdInfo, mkIdInfo,
+ exactArity, setUnfoldingInfo, setCafInfo, setCprInfo,
+ setArityInfo, setInlinePragInfo, setSpecInfo,
+ mkStrictnessInfo, setStrictnessInfo,
+ IdFlavour(..), InlinePragInfo(..), CafInfo(..), StrictnessInfo(..), CprInfo(..)
)
import FieldLabel ( FieldLabel, FieldLabelTag, mkFieldLabel, fieldLabelName,
- firstFieldLabelTag, allFieldLabelTags
+ firstFieldLabelTag, allFieldLabelTags, fieldLabelType
)
import CoreSyn
-import PrelVals ( rEC_SEL_ERROR_ID )
-import PrelMods ( pREL_GHC )
import Maybes
-import BasicTypes ( Arity, StrictnessMark(..) )
-import Unique ( Unique )
+import BasicTypes ( Arity )
+import Unique
import Maybe ( isJust )
import Outputable
import Util ( assoc )
%************************************************************************
%* *
+\subsection{Wired in Ids}
+%* *
+%************************************************************************
+
+\begin{code}
+wiredInIds
+ = [ -- These error-y things are wired in because we don't yet have
+ -- a way to express in an interface file that the result type variable
+ -- is 'open'; that is can be unified with an unboxed type
+ --
+ -- [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]
+
+ aBSENT_ERROR_ID
+ , eRROR_ID
+ , iRREFUT_PAT_ERROR_ID
+ , nON_EXHAUSTIVE_GUARDS_ERROR_ID
+ , nO_METHOD_BINDING_ERROR_ID
+ , pAR_ERROR_ID
+ , pAT_ERROR_ID
+ , rEC_CON_ERROR_ID
+ , rEC_UPD_ERROR_ID
+
+ -- These two can't be defined in Haskell
+ , realWorldPrimId
+ , unsafeCoerceId
+ , getTagId
+ ]
+\end{code}
+
+%************************************************************************
+%* *
\subsection{Easy ones}
%* *
%************************************************************************
\begin{code}
mkSpecPragmaId occ uniq ty loc
- = mkUserLocal occ uniq ty loc `setInlinePragma` IAmASpecPragmaId
+ = mkId (mkLocalName uniq occ loc) ty (mkIdInfo SpecPragmaId)
-- Maybe a SysLocal? But then we'd lose the location
mkDefaultMethodId dm_name rec_c ty
%************************************************************************
\begin{code}
-mkDataConId :: DataCon -> Id
-mkDataConId data_con
- = mkId (getName data_con)
- id_ty
- (ConstantId (DataCon data_con))
- (dataConInfo data_con)
+mkDataConId :: Name -> DataCon -> Id
+ -- Makes the *worker* for the data constructor; that is, the function
+ -- that takes the reprsentation arguments and builds the constructor.
+mkDataConId work_name data_con
+ = mkId work_name (dataConRepType data_con) info
where
- (tyvars, theta, ex_tyvars, ex_theta, arg_tys, tycon) = dataConSig data_con
- id_ty = mkSigmaTy (tyvars ++ ex_tyvars)
- (theta ++ ex_theta)
- (mkFunTys arg_tys (mkTyConApp tycon (mkTyVarTys tyvars)))
+ info = mkIdInfo (DataConId data_con)
+ `setArityInfo` exactArity arity
+ `setStrictnessInfo` strict_info
+ `setCprInfo` cpr_info
+
+ arity = dataConRepArity data_con
+
+ strict_info = mkStrictnessInfo (dataConRepStrictness data_con, False)
+
+ cpr_info | isProductTyCon tycon &&
+ not (isUnboxedTupleTyCon tycon) &&
+ arity > 0 = ReturnsCPR
+ | otherwise = NoCPRInfo
+ where
+ tycon = dataConTyCon data_con
+ -- Newtypes don't have a worker at all
+ --
+ -- If we are a product with 0 args we must be void(like)
+ -- We can't create an unboxed tuple with 0 args for this
+ -- and since Void has only one, constant value it should
+ -- just mean returning a pointer to a pre-existing cell.
+ -- So we won't really gain from doing anything fancy
+ -- and we treat this case as Top.
\end{code}
+The wrapper for a constructor is an ordinary top-level binding that evaluates
+any strict args, unboxes any args that are going to be flattened, and calls
+the worker.
+
We're going to build a constructor that looks like:
data (Data a, C b) => T a b = T1 !a !Int b
* We have to check that we can construct Data dictionaries for
the types a and Int. Once we've done that we can throw d1 away too.
-* We use (case p of ...) to evaluate p, rather than "seq" because
+* We use (case p of q -> ...) to evaluate p, rather than "seq" because
all that matters is that the arguments are evaluated. "seq" is
very careful to preserve evaluation order, which we don't need
to be here.
+ You might think that we could simply give constructors some strictness
+ info, like PrimOps, and let CoreToStg do the let-to-case transformation.
+ But we don't do that because in the case of primops and functions strictness
+ is a *property* not a *requirement*. In the case of constructors we need to
+ do something active to evaluate the argument.
+
+ Making an explicit case expression allows the simplifier to eliminate
+ it in the (common) case where the constructor arg is already evaluated.
+
\begin{code}
-dataConInfo :: DataCon -> IdInfo
-
-dataConInfo data_con
- = setInlinePragInfo IMustBeINLINEd $
- -- Always inline constructors; we won't create a binding for them
- setArityInfo (exactArity (length locals)) $
- setUnfoldingInfo unfolding $
- noIdInfo
+mkDataConWrapId data_con
+ = wrap_id
where
- unfolding = mkUnfolding con_rhs
-
- (tyvars, theta, ex_tyvars, ex_theta, arg_tys, tycon) = dataConSig data_con
- all_tyvars = tyvars ++ ex_tyvars
-
- dict_tys = [mkDictTy clas tys | (clas,tys) <- theta]
- ex_dict_tys = [mkDictTy clas tys | (clas,tys) <- ex_theta]
- n_dicts = length dict_tys
- result_ty = mkTyConApp tycon (mkTyVarTys tyvars)
-
- locals = mkTemplateLocals (dict_tys ++ ex_dict_tys ++ arg_tys)
- data_args = drop n_dicts locals
- (data_arg1:_) = data_args -- Used for newtype only
- strict_marks = dataConStrictMarks data_con
- strict_args = [arg | (arg,MarkedStrict) <- data_args `zip` strict_marks]
- -- NB: we can't call mkTemplateLocals twice, because it
- -- always starts from the same unique.
-
- con_app | isNewTyCon tycon
- = ASSERT( length arg_tys == 1)
- Note (Coerce result_ty (head arg_tys)) (Var data_arg1)
- | otherwise
- = mkConApp data_con (map Type (mkTyVarTys all_tyvars) ++ map Var data_args)
-
- con_rhs = mkLams all_tyvars $ mkLams locals $
- foldr mk_case con_app strict_args
-
- mk_case arg body | isUnLiftedType (idType arg)
- = body -- "!" on unboxed arg does nothing
- | otherwise
- = Case (Var arg) arg [(DEFAULT,[],body)]
- -- This case shadows "arg" but that's fine
+ wrap_id = mkId (dataConName data_con) wrap_ty info
+ work_id = dataConId data_con
+
+ info = mkIdInfo (DataConWrapId data_con)
+ `setUnfoldingInfo` mkTopUnfolding (mkInlineMe wrap_rhs)
+ `setCprInfo` cpr_info
+ -- The Cpr info can be important inside INLINE rhss, where the
+ -- wrapper constructor isn't inlined
+ `setArityInfo` exactArity arity
+ -- It's important to specify the arity, so that partial
+ -- applications are treated as values
+ `setCafInfo` NoCafRefs
+ -- The wrapper Id ends up in STG code as an argument,
+ -- sometimes before its definition, so we want to
+ -- signal that it has no CAFs
+
+ 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 )
+ -- 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)
+
+{- I nuked this because map (:) xs would create a
+ new local lambda for the (:) in core-to-stg.
+ There isn't a defn for the worker!
+
+ | 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,
+ -- which is a bit sad. (We could match on the wrappers,
+ -- but that makes it less likely that rules will match
+ -- when we bring bits of unfoldings together
+-}
+
+ | otherwise
+ = 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 []
+
+ con_app i rep_ids = mkApps (Var work_id)
+ (map varToCoreExpr (all_tyvars ++ reverse rep_ids))
+
+ (tyvars, theta, ex_tyvars, ex_theta, orig_arg_tys, tycon) = dataConSig data_con
+ all_tyvars = tyvars ++ ex_tyvars
+
+ dict_tys = mkDictTys theta
+ ex_dict_tys = mkDictTys ex_theta
+ all_arg_tys = dict_tys ++ ex_dict_tys ++ orig_arg_tys
+ result_ty = mkTyConApp tycon (mkTyVarTys tyvars)
+
+ mkLocals i tys = (zipWith mkTemplateLocal [i..i+n-1] tys, i+n)
+ where
+ n = length tys
+
+ (dict_args, i1) = mkLocals 1 dict_tys
+ (ex_dict_args,i2) = mkLocals i1 ex_dict_tys
+ (id_args,i3) = mkLocals i2 orig_arg_tys
+ arity = i3-1
+ (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
+ -> CoreExpr
+ mk_case (arg,strict) body i rep_args
+ = case strict of
+ NotMarkedStrict -> body i (arg:rep_args)
+ MarkedStrict
+ | isUnLiftedType (idType arg) -> body i (arg:rep_args)
+ | 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 n_tys = length tys
+ (con_args,i') = mkLocals i tys
\end{code}
T2 ... x ... -> x
other -> error "..."
+Similarly for newtypes
+
+ newtype N a = MkN { unN :: a->a }
+
+ unN :: N a -> a -> a
+ unN n = coerce (a->a) n
+
+We need to take a little care if the field has a polymorphic type:
+
+ data R = R { f :: forall a. a->a }
+
+Then we want
+
+ f :: forall a. R -> a -> a
+ f = /\ a \ r = case r of
+ R f -> f a
+
+(not f :: R -> forall a. a->a, which gives the type inference mechanism
+problems at call sites)
+
+Similarly for newtypes
+
+ newtype N = MkN { unN :: forall a. a->a }
+
+ unN :: forall a. N -> a -> a
+ unN = /\a -> \n:N -> coerce (a->a) n
+
\begin{code}
-mkRecordSelId field_label selector_ty
- = ASSERT( null theta && isDataTyCon tycon )
- sel_id
+mkRecordSelId tycon field_label unpack_id
+ -- Assumes that all fields with the same field label have the same type
+ --
+ -- Annoyingly, we have to pass in the unpackCString# Id, because
+ -- we can't conjure it up out of thin air
+ = sel_id
where
- sel_id = mkId (fieldLabelName field_label) selector_ty
- (RecordSelId field_label) info
-
- info = exactArity 1 `setArityInfo` (
- unfolding `setUnfoldingInfo`
- noIdInfo)
+ sel_id = mkId (fieldLabelName field_label) selector_ty info
+
+ field_ty = fieldLabelType field_label
+ field_name = fieldLabelName field_label
+ data_cons = tyConDataCons tycon
+ tyvars = tyConTyVars tycon -- These scope over the types in
+ -- the FieldLabels of constructors of this type
+ tycon_theta = tyConTheta tycon -- The context on the data decl
+ -- eg data (Eq a, Ord b) => T a b = ...
+ (field_tyvars,field_tau) = splitForAllTys field_ty
+
+ data_ty = mkTyConApp tycon tyvar_tys
+ tyvar_tys = mkTyVarTys tyvars
+
+ -- Very tiresomely, the selectors are (unnecessarily!) overloaded over
+ -- just the dictionaries in the types of the constructors that contain
+ -- the relevant field. Urgh.
+ -- NB: this code relies on the fact that DataCons are quantified over
+ -- the identical type variables as their parent TyCon
+ dict_tys = [mkDictTy cls tys | (cls, tys) <- tycon_theta, needed_dict (cls, tys)]
+ needed_dict pred = or [ pred `elem` (dataConTheta dc)
+ | (DataAlt dc, _, _) <- the_alts]
+
+ selector_ty :: Type
+ selector_ty = mkForAllTys tyvars $ mkForAllTys field_tyvars $
+ mkFunTys dict_tys $ mkFunTy data_ty field_tau
+
+ info = mkIdInfo (RecordSelId field_label)
+ `setArityInfo` exactArity (1 + length dict_tys)
+ `setUnfoldingInfo` unfolding
+ `setCafInfo` NoCafRefs
-- ToDo: consider adding further IdInfo
- unfolding = mkUnfolding sel_rhs
+ unfolding = mkTopUnfolding sel_rhs
- (tyvars, theta, tau) = splitSigmaTy selector_ty
- (data_ty,rhs_ty) = expectJust "StdIdInfoRec" (splitFunTy_maybe tau)
- -- tau is of form (T a b c -> field-type)
- (tycon, _, data_cons) = splitAlgTyConApp data_ty
- tyvar_tys = mkTyVarTys tyvars
- [data_id] = mkTemplateLocals [data_ty]
+ (data_id:dict_ids) = mkTemplateLocals (data_ty:dict_tys)
alts = map mk_maybe_alt data_cons
the_alts = catMaybes alts
default_alt | all isJust alts = [] -- No default needed
| otherwise = [(DEFAULT, [], error_expr)]
- sel_rhs = mkLams tyvars $ Lam data_id $
- Case (Var data_id) data_id (the_alts ++ default_alt)
+ sel_rhs | isNewTyCon tycon = new_sel_rhs
+ | otherwise = data_sel_rhs
+
+ data_sel_rhs = mkLams tyvars $ mkLams field_tyvars $
+ mkLams dict_ids $ Lam data_id $
+ Case (Var data_id) data_id (the_alts ++ default_alt)
+
+ new_sel_rhs = mkLams tyvars $ mkLams field_tyvars $ Lam data_id $
+ Note (Coerce (unUsgTy field_tau) (unUsgTy data_ty)) (Var data_id)
mk_maybe_alt data_con
= case maybe_the_arg_id of
Nothing -> Nothing
- Just the_arg_id -> Just (DataCon data_con, arg_ids, Var the_arg_id)
+ Just the_arg_id -> Just (DataAlt data_con, arg_ids,
+ mkVarApps (Var the_arg_id) field_tyvars)
where
arg_ids = mkTemplateLocals (dataConArgTys data_con tyvar_tys)
-- The first one will shadow data_id, but who cares
field_lbls = dataConFieldLabels data_con
maybe_the_arg_id = assocMaybe (field_lbls `zip` arg_ids) field_label
- error_expr = mkApps (Var rEC_SEL_ERROR_ID) [Type rhs_ty, mkStringLit full_msg]
+ error_expr = mkApps (Var rEC_SEL_ERROR_ID) [Type (unUsgTy field_tau), err_string]
+ -- preserves invariant that type args are *not* usage-annotated on top. KSW 1999-04.
+ err_string = App (Var unpack_id) (Lit (MachStr (_PK_ full_msg)))
full_msg = showSDoc (sep [text "No match in record selector", ppr sel_id])
\end{code}
%************************************************************************
%* *
-\subsection{Newtype field selectors}
-%* *
-%************************************************************************
-
-Possibly overkill to do it this way:
-
-\begin{code}
-mkNewTySelId field_label selector_ty = sel_id
- where
- sel_id = mkId (fieldLabelName field_label) selector_ty
- (RecordSelId field_label) info
-
- info = exactArity 1 `setArityInfo` (
- unfolding `setUnfoldingInfo`
- noIdInfo)
- -- ToDo: consider adding further IdInfo
-
- unfolding = mkUnfolding sel_rhs
-
- (tyvars, theta, tau) = splitSigmaTy selector_ty
- (data_ty,rhs_ty) = expectJust "StdIdInfoRec" (splitFunTy_maybe tau)
- -- tau is of form (T a b c -> field-type)
- (tycon, _, data_cons) = splitAlgTyConApp data_ty
- tyvar_tys = mkTyVarTys tyvars
-
- [data_id] = mkTemplateLocals [data_ty]
- sel_rhs = mkLams tyvars $ Lam data_id $
- Note (Coerce rhs_ty data_ty) (Var data_id)
-
-\end{code}
-
-
-%************************************************************************
-%* *
\subsection{Dictionary selectors}
%* *
%************************************************************************
-\begin{code}
-mkSuperDictSelId :: Unique -> Class -> FieldLabelTag -> Type -> Id
- -- The FieldLabelTag says which superclass is selected
- -- So, for
- -- class (C a, C b) => Foo a b where ...
- -- we get superclass selectors
- -- Foo_sc1, Foo_sc2
-
-mkSuperDictSelId uniq clas index ty
- = mkDictSelId name clas ty
- where
- name = mkDerivedName (mkSuperDictSelOcc index) (getName clas) uniq
-
- -- For method selectors the clean thing to do is
- -- to give the method selector the same name as the class op itself.
-mkMethodSelId name clas ty
- = mkDictSelId name clas ty
-\end{code}
-
Selecting a field for a dictionary. If there is just one field, then
-there's nothing to do.
+there's nothing to do.
+
+ToDo: unify with mkRecordSelId.
\begin{code}
-mkDictSelId name clas ty
+mkDictSelId :: Name -> Class -> Id
+mkDictSelId name clas
= sel_id
where
- sel_id = mkId name ty (RecordSelId field_lbl) info
- field_lbl = mkFieldLabel name ty tag
- tag = assoc "MkId.mkDictSelId" ((sc_sel_ids ++ op_sel_ids) `zip` allFieldLabelTags) sel_id
-
- info = setInlinePragInfo IMustBeINLINEd $
- setUnfoldingInfo unfolding noIdInfo
- -- The always-inline thing means we don't need any other IdInfo
- -- We need "Must" inline because we don't create any bindigs for
- -- the selectors.
+ ty = exprType rhs
+ sel_id = mkId name ty info
+ field_lbl = mkFieldLabel name tycon ty tag
+ tag = assoc "MkId.mkDictSelId" (classSelIds clas `zip` allFieldLabelTags) sel_id
+
+ info = mkIdInfo (RecordSelId field_lbl)
+ `setArityInfo` exactArity 1
+ `setUnfoldingInfo` unfolding
+ `setCafInfo` NoCafRefs
+
+ -- We no longer use 'must-inline' on record selectors. They'll
+ -- inline like crazy if they scrutinise a constructor
- unfolding = mkUnfolding rhs
+ unfolding = mkTopUnfolding rhs
- (tyvars, _, sc_sel_ids, op_sel_ids, defms) = classBigSig clas
+ tyvars = classTyVars clas
tycon = classTyCon clas
[data_con] = tyConDataCons tycon
Note (Coerce (head arg_tys) dict_ty) (Var dict_id)
| otherwise = mkLams tyvars $ Lam dict_id $
Case (Var dict_id) dict_id
- [(DataCon data_con, arg_ids, Var the_arg_id)]
+ [(DataAlt data_con, arg_ids, Var the_arg_id)]
\end{code}
%* *
%************************************************************************
-
\begin{code}
-mkPrimitiveId :: PrimOp -> Id
-mkPrimitiveId prim_op
+mkPrimOpId :: PrimOp -> Id
+mkPrimOpId prim_op
= id
where
- occ_name = primOpOcc prim_op
- key = primOpUniq prim_op
- ty = primOpType prim_op
- name = mkWiredInIdName key pREL_GHC occ_name id
- id = mkId name ty (ConstantId (PrimOp prim_op)) info
+ (tyvars,arg_tys,res_ty, arity, strict_info) = primOpSig prim_op
+ ty = mkForAllTys tyvars (mkFunTys arg_tys res_ty)
+ name = mkPrimOpIdName prim_op id
+ id = mkId name ty info
- info = setUnfoldingInfo unfolding $
- setInlinePragInfo IMustBeINLINEd $
- -- The pragma @IMustBeINLINEd@ says that this Id absolutely
- -- must be inlined. It's only used for primitives,
- -- because we don't want to make a closure for each of them.
- noIdInfo
-
- unfolding = mkUnfolding rhs
-
- (tyvars, tau) = splitForAllTys ty
- (arg_tys, _) = splitFunTys tau
+ info = mkIdInfo (PrimOpId prim_op)
+ `setSpecInfo` rules
+ `setArityInfo` exactArity arity
+ `setStrictnessInfo` strict_info
+
+ rules = addRule id emptyCoreRules (primOpRule prim_op)
+
+
+-- For each ccall we manufacture a separate CCallOpId, giving it
+-- a fresh unique, a type that is correct for this particular ccall,
+-- and a CCall structure that gives the correct details about calling
+-- convention etc.
+--
+-- The *name* of this Id is a local name whose OccName gives the full
+-- 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
+ = ASSERT( isEmptyVarSet (tyVarsOfType ty) )
+ -- A CCallOpId should have no free type variables;
+ -- when doing substitutions won't substitute over it
+ mkId name ty info
+ where
+ occ_str = showSDocIface (braces (pprCCallOp ccall <+> ppr ty))
+ -- The "occurrence name" of a ccall is the full info about the
+ -- ccall; it is encoded, but may have embedded spaces etc!
- args = mkTemplateLocals arg_tys
- rhs = mkLams tyvars $ mkLams args $
- mkPrimApp prim_op (map Type (mkTyVarTys tyvars) ++ map Var args)
-\end{code}
+ name = mkCCallName uniq occ_str
+ prim_op = CCallOp ccall
-\end{code}
+ info = mkIdInfo (PrimOpId prim_op)
+ `setArityInfo` exactArity arity
+ `setStrictnessInfo` strict_info
-\begin{code}
-dyadic_fun_ty ty = mkFunTys [ty, ty] ty
-monadic_fun_ty ty = ty `mkFunTy` ty
-compare_fun_ty ty = mkFunTys [ty, ty] boolTy
+ (_, tau) = splitForAllTys ty
+ (arg_tys, _) = splitFunTys tau
+ arity = length arg_tys
+ strict_info = mkStrictnessInfo (take arity (repeat wwPrim), False)
\end{code}
-> Class
-> [TyVar]
-> [Type]
- -> ThetaType
+ -> ClassContext
-> Id
mkDictFunId dfun_name clas inst_tyvars inst_tys inst_decl_theta
= mkVanillaId dfun_name dfun_ty
where
- (class_tyvars, sc_theta, _, _, _) = classBigSig clas
- sc_theta' = substTopTheta (zipVarEnv class_tyvars inst_tys) sc_theta
+ (class_tyvars, sc_theta, _, _) = classBigSig clas
+ sc_theta' = substClasses (mkTopTyVarSubst class_tyvars inst_tys) sc_theta
+
+ dfun_theta = classesToPreds inst_decl_theta
+
+{- 1 dec 99: disable the Mark Jones optimisation for the sake
+ of compatibility with Hugs.
+ See `types/InstEnv' for a discussion related to this.
dfun_theta = case inst_decl_theta of
[] -> [] -- If inst_decl_theta is empty, then we don't
-- want to have any dict arguments, so that we can
-- expose the constant methods.
- other -> nub (inst_decl_theta ++ sc_theta')
+ other -> nub (inst_decl_theta ++ filter not_const sc_theta')
-- Otherwise we pass the superclass dictionaries to
-- the dictionary function; the Mark Jones optimisation.
--
-- instance Monad m => MonadT (EnvT env) m where ...
-- Here, the inst_decl_theta has (Monad m); but so
-- does the sc_theta'!
-
+ --
+ -- NOTE the "not_const". I got caught by this one too:
+ -- class Foo a => Baz a b where ...
+ -- instance Wob b => Baz T b where..
+ -- Now sc_theta' has Foo T
+-}
dfun_ty = mkSigmaTy inst_tyvars dfun_theta (mkDictTy clas inst_tys)
+
+ not_const (clas, tys) = not (isEmptyVarSet (tyVarsOfTypes tys))
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsection{Un-definable}
+%* *
+%************************************************************************
+
+These two can't be defined in Haskell.
+
+unsafeCoerce# isn't so much a PrimOp as a phantom identifier, that
+just gets expanded into a type coercion wherever it occurs. Hence we
+add it as a built-in Id with an unfolding here.
+
+The type variables we use here are "open" type variables: this means
+they can unify with both unlifted and lifted types. Hence we provide
+another gun with which to shoot yourself in the foot.
+
+\begin{code}
+unsafeCoerceId
+ = pcMiscPrelId unsafeCoerceIdKey pREL_GHC SLIT("unsafeCoerce#") ty info
+ where
+ info = vanillaIdInfo
+ `setUnfoldingInfo` mkCompulsoryUnfolding rhs
+
+
+ ty = mkForAllTys [openAlphaTyVar,openBetaTyVar]
+ (mkFunTy openAlphaTy openBetaTy)
+ [x] = mkTemplateLocals [openAlphaTy]
+ rhs = mkLams [openAlphaTyVar,openBetaTyVar,x] $
+ Note (Coerce openBetaTy openAlphaTy) (Var x)
+\end{code}
+
+
+@getTag#@ is another function which can't be defined in Haskell. It needs to
+evaluate its argument and call the dataToTag# primitive.
+
+\begin{code}
+getTagId
+ = pcMiscPrelId getTagIdKey pREL_GHC SLIT("getTag#") ty info
+ where
+ info = vanillaIdInfo
+ `setUnfoldingInfo` mkCompulsoryUnfolding rhs
+ -- We don't provide a defn for this; you must inline it
+
+ ty = mkForAllTys [alphaTyVar] (mkFunTy alphaTy intPrimTy)
+ [x,y] = mkTemplateLocals [alphaTy,alphaTy]
+ rhs = mkLams [alphaTyVar,x] $
+ Case (Var x) y [ (DEFAULT, [], mkApps (Var dataToTagId) [Type alphaTy, Var y]) ]
+
+dataToTagId = mkPrimOpId DataToTagOp
\end{code}
+
+@realWorld#@ used to be a magic literal, \tr{void#}. If things get
+nasty as-is, change it back to a literal (@Literal@).
+
+\begin{code}
+realWorldPrimId -- :: State# RealWorld
+ = pcMiscPrelId realWorldPrimIdKey pREL_GHC SLIT("realWorld#")
+ realWorldStatePrimTy
+ (noCafIdInfo `setUnfoldingInfo` mkOtherCon [])
+ -- The mkOtherCon makes it look that realWorld# is evaluated
+ -- which in turn makes Simplify.interestingArg return True,
+ -- which in turn makes INLINE things applied to realWorld# likely
+ -- to be inlined
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsection[PrelVals-error-related]{@error@ and friends; @trace@}
+%* *
+%************************************************************************
+
+GHC randomly injects these into the code.
+
+@patError@ is just a version of @error@ for pattern-matching
+failures. It knows various ``codes'' which expand to longer
+strings---this saves space!
+
+@absentErr@ is a thing we put in for ``absent'' arguments. They jolly
+well shouldn't be yanked on, but if one is, then you will get a
+friendly message from @absentErr@ (rather than a totally random
+crash).
+
+@parError@ is a special version of @error@ which the compiler does
+not know to be a bottoming Id. It is used in the @_par_@ and @_seq_@
+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
+pAT_ERROR_ID
+ = generic_ERROR_ID patErrorIdKey SLIT("patError")
+rEC_SEL_ERROR_ID
+ = generic_ERROR_ID recSelErrIdKey SLIT("recSelError")
+rEC_CON_ERROR_ID
+ = generic_ERROR_ID recConErrorIdKey SLIT("recConError")
+rEC_UPD_ERROR_ID
+ = generic_ERROR_ID recUpdErrorIdKey SLIT("recUpdError")
+iRREFUT_PAT_ERROR_ID
+ = generic_ERROR_ID irrefutPatErrorIdKey SLIT("irrefutPatError")
+nON_EXHAUSTIVE_GUARDS_ERROR_ID
+ = generic_ERROR_ID nonExhaustiveGuardsErrorIdKey SLIT("nonExhaustiveGuardsError")
+nO_METHOD_BINDING_ERROR_ID
+ = generic_ERROR_ID noMethodBindingErrorIdKey SLIT("noMethodBindingError")
+
+aBSENT_ERROR_ID
+ = pc_bottoming_Id absentErrorIdKey pREL_ERR SLIT("absentErr")
+ (mkSigmaTy [openAlphaTyVar] [] openAlphaTy)
+
+pAR_ERROR_ID
+ = pcMiscPrelId parErrorIdKey pREL_ERR SLIT("parError")
+ (mkSigmaTy [openAlphaTyVar] [] openAlphaTy) noCafIdInfo
+
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsection{Utilities}
+%* *
+%************************************************************************
+
+\begin{code}
+pcMiscPrelId :: Unique{-IdKey-} -> Module -> FAST_STRING -> Type -> IdInfo -> Id
+pcMiscPrelId key mod str ty info
+ = let
+ name = mkWiredInIdName key mod (mkSrcVarOcc str) imp
+ imp = mkId name ty info -- the usual case...
+ in
+ imp
+ -- We lie and say the thing is imported; otherwise, we get into
+ -- a mess with dependency analysis; e.g., core2stg may heave in
+ -- random calls to GHCbase.unpackPS__. If GHCbase is the module
+ -- being compiled, then it's just a matter of luck if the definition
+ -- will be in "the right place" to be in scope.
+
+pc_bottoming_Id key mod name ty
+ = pcMiscPrelId key mod name ty bottoming_info
+ where
+ bottoming_info = noCafIdInfo
+ `setStrictnessInfo` mkStrictnessInfo ([wwStrict], True)
+
+ -- these "bottom" out, no matter what their arguments
+
+generic_ERROR_ID u n = pc_bottoming_Id u pREL_ERR n errorTy
+
+-- Very useful...
+noCafIdInfo = vanillaIdInfo `setCafInfo` NoCafRefs
+
+(openAlphaTyVar:openBetaTyVar:_) = openAlphaTyVars
+openAlphaTy = mkTyVarTy openAlphaTyVar
+openBetaTy = mkTyVarTy openBetaTyVar
+
+errorTy :: Type
+errorTy = mkUsgTy UsMany $
+ mkSigmaTy [openAlphaTyVar] [] (mkFunTys [mkUsgTy UsOnce (mkListTy charTy)]
+ (mkUsgTy UsMany openAlphaTy))
+ -- Notice the openAlphaTyVar. It says that "error" can be applied
+ -- to unboxed as well as boxed types. This is OK because it never
+ -- returns, so the return type is irrelevant.
+\end{code}
+