import TysPrim
import TysWiredIn
import PrelRules
+import Unify
import Type
import TypeRep
-import TcGadt
import Coercion
import TcType
import CoreUtils
-- Allocate Ids. We do it a funny way round because field_dict_tys is
-- almost always empty. Also note that we use max_dict_tys
-- rather than n_dict_tys, because the latter gives an infinite loop:
- -- n_dict tys depends on the_alts, which depens on arg_ids, which depends
- -- on arity, which depends on n_dict tys. Sigh! Mega sigh!
+ -- n_dict tys depends on the_alts, which depens on arg_ids, which
+ -- depends on arity, which depends on n_dict tys. Sigh! Mega sigh!
stupid_dict_ids = mkTemplateLocalsNum 1 stupid_dict_tys
max_stupid_dicts = length (tyConStupidTheta tycon)
field_dict_base = max_stupid_dicts + 1
-- foo :: forall a. T -> a -> a
-- foo = /\a. \t:T. case t of { MkT f -> f a }
- mk_alt data_con
- = ASSERT2( data_ty `tcEqType` field_ty, ppr data_con $$ ppr data_ty $$ ppr field_ty )
+ mk_alt data_con
+ = 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 scrut_ty_args
+ (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..]
-- Generate the refinement for b'=b,
-- and apply to (Maybe b'), to get (Maybe b)
- 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)
+ reft = matchRefine co_tvs
+ the_arg_id_ty = idType the_arg_id
+ (rhs, data_ty) =
+ case refineType reft 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
+ the_arg_id = assoc "mkRecordSelId:mk_alt"
+ (field_lbls `zip` field_vs) field_label
field_lbls = dataConFieldLabels data_con
error_expr = mkRuntimeErrorApp rEC_SEL_ERROR_ID field_ty full_msg
-- will be in "the right place" to be in scope.
pc_bottoming_Id :: Name -> Type -> Id
+-- Function of arity 1, which diverges after being given one argument
pc_bottoming_Id name ty
= pcMiscPrelId name ty bottoming_info
where
bottoming_info = vanillaIdInfo `setAllStrictnessInfo` Just strict_sig
+ `setArityInfo` 1
+ -- Make arity and strictness agree
+
-- Do *not* mark them as NoCafRefs, because they can indeed have
-- CAF refs. For example, pAT_ERROR_ID calls GHC.Err.untangle,
-- which has some CAFs
-- any pc_bottoming_Id will itself have CafRefs, which bloats
-- SRTs.
- strict_sig = mkStrictSig (mkTopDmdType [evalDmd] BotRes)
+ strict_sig = mkStrictSig (mkTopDmdType [evalDmd] BotRes)
-- These "bottom" out, no matter what their arguments
\end{code}