module GHC.HsToCore.Expr
( dsExpr, dsLExpr, dsLocalBinds
, dsValBinds, dsLit, dsSyntaxExpr
)
where
import GHC.Prelude
import GHC.HsToCore.Match
import GHC.HsToCore.Match.Literal
import GHC.HsToCore.Binds
import GHC.HsToCore.GuardedRHSs
import GHC.HsToCore.ListComp
import GHC.HsToCore.Utils
import GHC.HsToCore.Arrows
import GHC.HsToCore.Monad
import GHC.HsToCore.Pmc ( addTyCs, pmcGRHSs )
import GHC.HsToCore.Errors.Types
import GHC.Types.SourceText
import GHC.Types.Name
import GHC.Types.Name.Env
import GHC.Core.FamInstEnv( topNormaliseType )
import GHC.HsToCore.Quote
import GHC.Hs
import GHC.Tc.Utils.TcType
import GHC.Tc.Types.Evidence
import GHC.Tc.Utils.Monad
import GHC.Core.Type
import GHC.Core.TyCo.Rep
import GHC.Core.Multiplicity
import GHC.Core
import GHC.Core.Utils
import GHC.Core.Make
import GHC.Driver.Session
import GHC.Types.CostCentre
import GHC.Types.Id
import GHC.Types.Id.Make
import GHC.Types.Var.Env
import GHC.Unit.Module
import GHC.Core.ConLike
import GHC.Core.DataCon
import GHC.Builtin.Types
import GHC.Builtin.Names
import GHC.Types.Basic
import GHC.Data.Maybe
import GHC.Types.SrcLoc
import GHC.Types.Tickish
import GHC.Utils.Misc
import GHC.Data.Bag
import GHC.Utils.Outputable as Outputable
import GHC.Utils.Panic
import GHC.Utils.Panic.Plain
import GHC.Core.PatSyn
import Control.Monad
dsLocalBinds :: HsLocalBinds GhcTc -> CoreExpr -> DsM CoreExpr
dsLocalBinds (EmptyLocalBinds _) body = return body
dsLocalBinds b@(HsValBinds _ binds) body = putSrcSpanDs (spanHsLocaLBinds b) $
dsValBinds binds body
dsLocalBinds (HsIPBinds _ binds) body = dsIPBinds binds body
dsValBinds :: HsValBinds GhcTc -> CoreExpr -> DsM CoreExpr
dsValBinds (XValBindsLR (NValBinds binds _)) body
= foldrM ds_val_bind body binds
dsValBinds (ValBinds {}) _ = panic "dsValBinds ValBindsIn"
dsIPBinds :: HsIPBinds GhcTc -> CoreExpr -> DsM CoreExpr
dsIPBinds (IPBinds ev_binds ip_binds) body
= do { ds_binds <- dsTcEvBinds ev_binds
; let inner = mkCoreLets ds_binds body
; foldrM ds_ip_bind inner ip_binds }
where
ds_ip_bind :: LIPBind GhcTc -> CoreExpr -> DsM CoreExpr
ds_ip_bind (L _ (IPBind n _ e)) body
= do e' <- dsLExpr e
return (Let (NonRec n e') body)
ds_val_bind :: (RecFlag, LHsBinds GhcTc) -> CoreExpr -> DsM CoreExpr
ds_val_bind (NonRecursive, hsbinds) body
| [L loc bind] <- bagToList hsbinds
, isUnliftedHsBind bind
= putSrcSpanDs (locA loc) $
if is_polymorphic bind
then errDsCoreExpr (DsCannotMixPolyAndUnliftedBindings bind)
else do { when (looksLazyPatBind bind) $
diagnosticDs (DsUnbangedStrictPatterns bind)
; dsUnliftedBind bind body }
where
is_polymorphic (XHsBindsLR (AbsBinds { abs_tvs = tvs, abs_ev_vars = evs }))
= not (null tvs && null evs)
is_polymorphic _ = False
ds_val_bind (is_rec, binds) _body
| anyBag (isUnliftedHsBind . unLoc) binds
= assert (isRec is_rec )
errDsCoreExpr $ DsRecBindsNotAllowedForUnliftedTys (bagToList binds)
ds_val_bind (is_rec, binds) body
= do { massert (isRec is_rec || isSingletonBag binds)
; (force_vars,prs) <- dsLHsBinds binds
; let body' = foldr seqVar body force_vars
; assertPpr (not (any (isUnliftedType . idType . fst) prs)) (ppr is_rec $$ ppr binds) $
case prs of
[] -> return body
_ -> return (Let (Rec prs) body') }
dsUnliftedBind :: HsBind GhcTc -> CoreExpr -> DsM CoreExpr
dsUnliftedBind (XHsBindsLR (AbsBinds { abs_tvs = [], abs_ev_vars = []
, abs_exports = exports
, abs_ev_binds = ev_binds
, abs_binds = lbinds })) body
= do { let body1 = foldr bind_export body exports
bind_export export b = bindNonRec (abe_poly export) (Var (abe_mono export)) b
; body2 <- foldlM (\body lbind -> dsUnliftedBind (unLoc lbind) body)
body1 lbinds
; ds_binds <- dsTcEvBinds_s ev_binds
; return (mkCoreLets ds_binds body2) }
dsUnliftedBind (FunBind { fun_id = L l fun
, fun_matches = matches
, fun_ext = co_fn
, fun_tick = tick }) body
= do { (args, rhs) <- matchWrapper (mkPrefixFunRhs (L l $ idName fun)) Nothing matches
; massert (null args)
; core_wrap <- dsHsWrapper co_fn
; let rhs' = core_wrap (mkOptTickBox tick rhs)
; return (bindNonRec fun rhs' body) }
dsUnliftedBind (PatBind {pat_lhs = pat, pat_rhs = grhss
, pat_ext = ty }) body
=
do { match_nablas <- pmcGRHSs PatBindGuards grhss
; rhs <- dsGuarded grhss ty match_nablas
; let upat = unLoc pat
eqn = EqnInfo { eqn_pats = [upat],
eqn_orig = FromSource,
eqn_rhs = cantFailMatchResult body }
; var <- selectMatchVar Many upat
; result <- matchEquations PatBindRhs [var] [eqn] (exprType body)
; return (bindNonRec var rhs result) }
dsUnliftedBind bind body = pprPanic "dsLet: unlifted" (ppr bind $$ ppr body)
dsLExpr :: LHsExpr GhcTc -> DsM CoreExpr
dsLExpr (L loc e) =
putSrcSpanDsA loc $ dsExpr e
dsExpr :: HsExpr GhcTc -> DsM CoreExpr
dsExpr (HsVar _ (L _ id)) = dsHsVar id
dsExpr (HsRecSel _ (FieldOcc id _)) = dsHsVar id
dsExpr (HsUnboundVar (HER ref _ _) _) = dsEvTerm =<< readMutVar ref
dsExpr (HsPar _ _ e _) = dsLExpr e
dsExpr (ExprWithTySig _ e _) = dsLExpr e
dsExpr (HsIPVar x _) = dataConCantHappen x
dsExpr (HsGetField x _ _) = dataConCantHappen x
dsExpr (HsProjection x _) = dataConCantHappen x
dsExpr (HsLit _ lit)
= do { warnAboutOverflowedLit lit
; dsLit (convertLit lit) }
dsExpr (HsOverLit _ lit)
= do { warnAboutOverflowedOverLit lit
; dsOverLit lit }
dsExpr e@(XExpr ext_expr_tc)
= case ext_expr_tc of
ExpansionExpr (HsExpanded _ b) -> dsExpr b
WrapExpr {} -> dsHsWrapped e
ConLikeTc con tvs tys -> dsConLike con tvs tys
HsTick tickish e -> do
e' <- dsLExpr e
return (Tick tickish e')
HsBinTick ixT ixF e -> do
e2 <- dsLExpr e
do { assert (exprType e2 `eqType` boolTy)
mkBinaryTickBox ixT ixF e2
}
dsExpr (NegApp _ (L loc
(HsOverLit _ lit@(OverLit { ol_val = HsIntegral i})))
neg_expr)
= do { expr' <- putSrcSpanDsA loc $ do
{ warnAboutOverflowedOverLit
(lit { ol_val = HsIntegral (negateIntegralLit i) })
; dsOverLit lit }
; dsSyntaxExpr neg_expr [expr'] }
dsExpr (NegApp _ expr neg_expr)
= do { expr' <- dsLExpr expr
; dsSyntaxExpr neg_expr [expr'] }
dsExpr (HsLam _ a_Match)
= uncurry mkCoreLams <$> matchWrapper LambdaExpr Nothing a_Match
dsExpr (HsLamCase _ lc_variant matches)
= uncurry mkCoreLams <$> matchWrapper (LamCaseAlt lc_variant) Nothing matches
dsExpr e@(HsApp _ fun arg)
= do { fun' <- dsLExpr fun
; arg' <- dsLExpr arg
; return $ mkCoreAppDs (text "HsApp" <+> ppr e) fun' arg' }
dsExpr e@(HsAppType {}) = dsHsWrapped e
dsExpr (ExplicitTuple _ tup_args boxity)
= do { let go (lam_vars, args) (Missing (Scaled mult ty))
= do { lam_var <- newSysLocalDs mult ty
; return (lam_var : lam_vars, Var lam_var : args) }
go (lam_vars, args) (Present _ expr)
= do { core_expr <- dsLExpr expr
; return (lam_vars, core_expr : args) }
; (lam_vars, args) <- foldM go ([], []) (reverse tup_args)
; return $ mkCoreLams lam_vars (mkCoreTupBoxity boxity args) }
dsExpr (ExplicitSum types alt arity expr)
= mkCoreUbxSum arity alt types <$> dsLExpr expr
dsExpr (HsPragE _ prag expr) =
ds_prag_expr prag expr
dsExpr (HsCase _ discrim matches)
= do { core_discrim <- dsLExpr discrim
; ([discrim_var], matching_code) <- matchWrapper CaseAlt (Just [discrim]) matches
; return (bindNonRec discrim_var core_discrim matching_code) }
dsExpr (HsLet _ _ binds _ body) = do
body' <- dsLExpr body
dsLocalBinds binds body'
dsExpr (HsDo res_ty ListComp (L _ stmts)) = dsListComp stmts res_ty
dsExpr (HsDo _ ctx@DoExpr{} (L _ stmts)) = dsDo ctx stmts
dsExpr (HsDo _ ctx@GhciStmtCtxt (L _ stmts)) = dsDo ctx stmts
dsExpr (HsDo _ ctx@MDoExpr{} (L _ stmts)) = dsDo ctx stmts
dsExpr (HsDo _ MonadComp (L _ stmts)) = dsMonadComp stmts
dsExpr (HsIf _ guard_expr then_expr else_expr)
= do { pred <- dsLExpr guard_expr
; b1 <- dsLExpr then_expr
; b2 <- dsLExpr else_expr
; return $ mkIfThenElse pred b1 b2 }
dsExpr (HsMultiIf res_ty alts)
| null alts
= mkErrorExpr
| otherwise
= do { let grhss = GRHSs emptyComments alts emptyLocalBinds
; rhss_nablas <- pmcGRHSs IfAlt grhss
; match_result <- dsGRHSs IfAlt grhss res_ty rhss_nablas
; error_expr <- mkErrorExpr
; extractMatchResult match_result error_expr }
where
mkErrorExpr = mkErrorAppDs nON_EXHAUSTIVE_GUARDS_ERROR_ID res_ty
(text "multi-way if")
dsExpr (ExplicitList elt_ty xs) = dsExplicitList elt_ty xs
dsExpr (ArithSeq expr witness seq)
= case witness of
Nothing -> dsArithSeq expr seq
Just fl -> do { newArithSeq <- dsArithSeq expr seq
; dsSyntaxExpr fl [newArithSeq] }
dsExpr (HsStatic (_, whole_ty) expr@(L loc _)) = do
expr_ds <- dsLExpr expr
let (_, [ty]) = splitTyConApp whole_ty
makeStaticId <- dsLookupGlobalId makeStaticName
dflags <- getDynFlags
let platform = targetPlatform dflags
let (line, col) = case locA loc of
RealSrcSpan r _ ->
( srcLocLine $ realSrcSpanStart r
, srcLocCol $ realSrcSpanStart r
)
_ -> (0, 0)
srcLoc = mkCoreConApps (tupleDataCon Boxed 2)
[ Type intTy , Type intTy
, mkIntExprInt platform line, mkIntExprInt platform col
]
putSrcSpanDsA loc $ return $
mkCoreApps (Var makeStaticId) [ Type ty, srcLoc, expr_ds ]
dsExpr (RecordCon { rcon_con = L _ con_like
, rcon_flds = rbinds
, rcon_ext = con_expr })
= do { con_expr' <- dsExpr con_expr
; let
(arg_tys, _) = tcSplitFunTys (exprType con_expr')
mk_arg (arg_ty, fl)
= case findField (rec_flds rbinds) (flSelector fl) of
(rhs:rhss) -> assert (null rhss)
dsLExpr rhs
[] -> mkErrorAppDs rEC_CON_ERROR_ID arg_ty (ppr (flLabel fl))
unlabelled_bottom arg_ty = mkErrorAppDs rEC_CON_ERROR_ID arg_ty Outputable.empty
labels = conLikeFieldLabels con_like
; con_args <- if null labels
then mapM unlabelled_bottom (map scaledThing arg_tys)
else mapM mk_arg (zipEqual "dsExpr:RecordCon" (map scaledThing arg_tys) labels)
; return (mkCoreApps con_expr' con_args) }
dsExpr RecordUpd { rupd_flds = Right _} =
panic "The impossible happened"
dsExpr expr@(RecordUpd { rupd_expr = record_expr, rupd_flds = Left fields
, rupd_ext = RecordUpdTc
{ rupd_cons = cons_to_upd
, rupd_in_tys = in_inst_tys
, rupd_out_tys = out_inst_tys
, rupd_wrap = dict_req_wrap }} )
| null fields
= dsLExpr record_expr
| otherwise
= assertPpr (notNull cons_to_upd) (ppr expr) $
do { record_expr' <- dsLExpr record_expr
; field_binds' <- mapM ds_field fields
; let upd_fld_env :: NameEnv Id
upd_fld_env = mkNameEnv [(f,l) | (f,l,_) <- field_binds']
; alts <- mapM (mk_alt upd_fld_env) cons_to_upd
; ([discrim_var], matching_code)
<- matchWrapper RecUpd (Just [record_expr])
(MG { mg_alts = noLocA alts
, mg_ext = MatchGroupTc [unrestricted in_ty] out_ty
, mg_origin = FromSource
})
; return (add_field_binds field_binds' $
bindNonRec discrim_var record_expr' matching_code) }
where
ds_field :: LHsRecUpdField GhcTc -> DsM (Name, Id, CoreExpr)
ds_field (L _ rec_field)
= do { rhs <- dsLExpr (hfbRHS rec_field)
; let fld_id = unLoc (hsRecUpdFieldId rec_field)
; lcl_id <- newSysLocalDs (idMult fld_id) (idType fld_id)
; return (idName fld_id, lcl_id, rhs) }
add_field_binds [] expr = expr
add_field_binds ((_,b,r):bs) expr = bindNonRec b r (add_field_binds bs expr)
(in_ty, out_ty) =
case (head cons_to_upd) of
RealDataCon data_con ->
let tycon = dataConTyCon data_con in
(mkTyConApp tycon in_inst_tys, mkFamilyTyConApp tycon out_inst_tys)
PatSynCon pat_syn ->
( patSynInstResTy pat_syn in_inst_tys
, patSynInstResTy pat_syn out_inst_tys)
mk_alt upd_fld_env con
= do { let (univ_tvs, ex_tvs, eq_spec,
prov_theta, _req_theta, arg_tys, _) = conLikeFullSig con
arg_tys' = map (scaleScaled Many) arg_tys
user_tvs = binderVars $ conLikeUserTyVarBinders con
in_subst :: TCvSubst
in_subst = extendTCvInScopeList (zipTvSubst univ_tvs in_inst_tys) ex_tvs
out_tv_env :: TvSubstEnv
out_tv_env = zipTyEnv univ_tvs out_inst_tys
; eqs_vars <- mapM newPredVarDs (substTheta in_subst (eqSpecPreds eq_spec))
; theta_vars <- mapM newPredVarDs (substTheta in_subst prov_theta)
; arg_ids <- newSysLocalsDs (substScaledTysUnchecked in_subst arg_tys')
; let field_labels = conLikeFieldLabels con
val_args = zipWithEqual "dsExpr:RecordUpd" mk_val_arg
field_labels arg_ids
mk_val_arg fl pat_arg_id
= nlHsVar (lookupNameEnv upd_fld_env (flSelector fl) `orElse` pat_arg_id)
inst_con = noLocA $ mkHsWrap wrap (mkConLikeTc con)
wrap = mkWpEvVarApps theta_vars <.>
dict_req_wrap <.>
mkWpTyApps [ lookupVarEnv out_tv_env tv
`orElse` mkTyVarTy tv
| tv <- user_tvs ]
rhs = foldl' (\a b -> nlHsApp a b) inst_con val_args
wrapped_rhs =
case con of
RealDataCon data_con
| null eq_spec -> rhs
| otherwise -> mkLHsWrap (mkWpCastN wrap_co) rhs
where
rep_tc = dataConTyCon data_con
wrap_co = mkTcFamilyTyConAppCo rep_tc univ_cos
univ_cos = zipWithEqual "dsExpr:upd" mk_univ_co univ_tvs out_inst_tys
mk_univ_co :: TyVar
-> Type
-> Coercion
mk_univ_co univ_tv inst_ty
= case lookupVarEnv eq_spec_env univ_tv of
Just co -> co
Nothing -> mkTcNomReflCo inst_ty
eq_spec_env :: VarEnv Coercion
eq_spec_env = mkVarEnv [ (eqSpecTyVar spec, mkTcSymCo (mkTcCoVarCo eqs_var))
| (spec,eqs_var) <- zipEqual "dsExpr:upd2" eq_spec eqs_vars ]
PatSynCon _ -> rhs
req_wrap = dict_req_wrap <.> mkWpTyApps in_inst_tys
pat = noLocA $ ConPat { pat_con = noLocA con
, pat_args = PrefixCon [] $ map nlVarPat arg_ids
, pat_con_ext = ConPatTc
{ cpt_tvs = ex_tvs
, cpt_dicts = eqs_vars ++ theta_vars
, cpt_binds = emptyTcEvBinds
, cpt_arg_tys = in_inst_tys
, cpt_wrap = req_wrap
}
}
; return (mkSimpleMatch RecUpd [pat] wrapped_rhs) }
dsExpr (HsTypedBracket (HsBracketTc q _ hs_wrapper ps) _) = dsBracket hs_wrapper q ps
dsExpr (HsUntypedBracket (HsBracketTc q _ hs_wrapper ps) _) = dsBracket hs_wrapper q ps
dsExpr (HsSpliceE _ s) = pprPanic "dsExpr:splice" (ppr s)
dsExpr (HsProc _ pat cmd) = dsProcExpr pat cmd
dsExpr (HsOverLabel x _) = dataConCantHappen x
dsExpr (OpApp x _ _ _) = dataConCantHappen x
dsExpr (SectionL x _ _) = dataConCantHappen x
dsExpr (SectionR x _ _) = dataConCantHappen x
ds_prag_expr :: HsPragE GhcTc -> LHsExpr GhcTc -> DsM CoreExpr
ds_prag_expr (HsPragSCC _ _ cc) expr = do
dflags <- getDynFlags
if sccProfilingEnabled dflags && gopt Opt_ProfManualCcs dflags
then do
mod_name <- getModule
count <- goptM Opt_ProfCountEntries
let nm = sl_fs cc
flavour <- ExprCC <$> getCCIndexDsM nm
Tick (ProfNote (mkUserCC nm mod_name (getLocA expr) flavour) count True)
<$> dsLExpr expr
else dsLExpr expr
dsSyntaxExpr :: SyntaxExpr GhcTc -> [CoreExpr] -> DsM CoreExpr
dsSyntaxExpr (SyntaxExprTc { syn_expr = expr
, syn_arg_wraps = arg_wraps
, syn_res_wrap = res_wrap })
arg_exprs
= do { fun <- dsExpr expr
; core_arg_wraps <- mapM dsHsWrapper arg_wraps
; core_res_wrap <- dsHsWrapper res_wrap
; let wrapped_args = zipWithEqual "dsSyntaxExpr" ($) core_arg_wraps arg_exprs
; return $ core_res_wrap (mkCoreApps fun wrapped_args) }
dsSyntaxExpr NoSyntaxExprTc _ = panic "dsSyntaxExpr"
findField :: [LHsRecField GhcTc arg] -> Name -> [arg]
findField rbinds sel
= [hfbRHS fld | L _ fld <- rbinds
, sel == idName (hsRecFieldId fld) ]
maxBuildLength :: Int
maxBuildLength = 32
dsExplicitList :: Type -> [LHsExpr GhcTc]
-> DsM CoreExpr
dsExplicitList elt_ty xs
= do { dflags <- getDynFlags
; xs' <- mapM dsLExpr xs
; if xs' `lengthExceeds` maxBuildLength
|| null xs'
|| not (gopt Opt_EnableRewriteRules dflags)
then return $ mkListExpr elt_ty xs'
else mkBuildExpr elt_ty (mk_build_list xs') }
where
mk_build_list xs' (cons, _) (nil, _)
= return (foldr (App . App (Var cons)) (Var nil) xs')
dsArithSeq :: PostTcExpr -> (ArithSeqInfo GhcTc) -> DsM CoreExpr
dsArithSeq expr (From from)
= App <$> dsExpr expr <*> dsLExpr from
dsArithSeq expr (FromTo from to)
= do fam_envs <- dsGetFamInstEnvs
dflags <- getDynFlags
warnAboutEmptyEnumerations fam_envs dflags from Nothing to
expr' <- dsExpr expr
from' <- dsLExpr from
to' <- dsLExpr to
return $ mkApps expr' [from', to']
dsArithSeq expr (FromThen from thn)
= mkApps <$> dsExpr expr <*> mapM dsLExpr [from, thn]
dsArithSeq expr (FromThenTo from thn to)
= do fam_envs <- dsGetFamInstEnvs
dflags <- getDynFlags
warnAboutEmptyEnumerations fam_envs dflags from (Just thn) to
expr' <- dsExpr expr
from' <- dsLExpr from
thn' <- dsLExpr thn
to' <- dsLExpr to
return $ mkApps expr' [from', thn', to']
dsDo :: HsDoFlavour -> [ExprLStmt GhcTc] -> DsM CoreExpr
dsDo ctx stmts
= goL stmts
where
goL [] = panic "dsDo"
goL ((L loc stmt):lstmts) = putSrcSpanDsA loc (go loc stmt lstmts)
go _ (LastStmt _ body _ _) stmts
= assert (null stmts ) dsLExpr body
go _ (BodyStmt _ rhs then_expr _) stmts
= do { rhs2 <- dsLExpr rhs
; warnDiscardedDoBindings rhs (exprType rhs2)
; rest <- goL stmts
; dsSyntaxExpr then_expr [rhs2, rest] }
go _ (LetStmt _ binds) stmts
= do { rest <- goL stmts
; dsLocalBinds binds rest }
go _ (BindStmt xbs pat rhs) stmts
= do { body <- goL stmts
; rhs' <- dsLExpr rhs
; var <- selectSimpleMatchVarL (xbstc_boundResultMult xbs) pat
; match <- matchSinglePatVar var Nothing (StmtCtxt (HsDoStmt ctx)) pat
(xbstc_boundResultType xbs) (cantFailMatchResult body)
; match_code <- dsHandleMonadicFailure ctx pat match (xbstc_failOp xbs)
; dsSyntaxExpr (xbstc_bindOp xbs) [rhs', Lam var match_code] }
go _ (ApplicativeStmt body_ty args mb_join) stmts
= do {
let
(pats, rhss) = unzip (map (do_arg . snd) args)
do_arg (ApplicativeArgOne fail_op pat expr _) =
((pat, fail_op), dsLExpr expr)
do_arg (ApplicativeArgMany _ stmts ret pat _) =
((pat, Nothing), dsDo ctx (stmts ++ [noLocA $ mkLastStmt (noLocA ret)]))
; rhss' <- sequence rhss
; body' <- dsLExpr $ noLocA $ HsDo body_ty ctx (noLocA stmts)
; let match_args (pat, fail_op) (vs,body)
= putSrcSpanDs (getLocA pat) $
do { var <- selectSimpleMatchVarL Many pat
; match <- matchSinglePatVar var Nothing (StmtCtxt (HsDoStmt ctx)) pat
body_ty (cantFailMatchResult body)
; match_code <- dsHandleMonadicFailure ctx pat match fail_op
; return (var:vs, match_code)
}
; (vars, body) <- foldrM match_args ([],body') pats
; let fun' = mkLams vars body
; let mk_ap_call l (op,r) = dsSyntaxExpr op [l,r]
; expr <- foldlM mk_ap_call fun' (zip (map fst args) rhss')
; case mb_join of
Nothing -> return expr
Just join_op -> dsSyntaxExpr join_op [expr] }
go loc (RecStmt { recS_stmts = L _ rec_stmts, recS_later_ids = later_ids
, recS_rec_ids = rec_ids, recS_ret_fn = return_op
, recS_mfix_fn = mfix_op, recS_bind_fn = bind_op
, recS_ext = RecStmtTc
{ recS_bind_ty = bind_ty
, recS_rec_rets = rec_rets
, recS_ret_ty = body_ty} }) stmts
= goL (new_bind_stmt : stmts)
where
new_bind_stmt = L loc $ BindStmt
XBindStmtTc
{ xbstc_bindOp = bind_op
, xbstc_boundResultType = bind_ty
, xbstc_boundResultMult = Many
, xbstc_failOp = Nothing
}
(mkBigLHsPatTupId later_pats)
mfix_app
tup_ids = rec_ids ++ filterOut (`elem` rec_ids) later_ids
tup_ty = mkBigCoreTupTy (map idType tup_ids)
rec_tup_pats = map nlVarPat tup_ids
later_pats = rec_tup_pats
rets = map noLocA rec_rets
mfix_app = nlHsSyntaxApps mfix_op [mfix_arg]
mfix_arg = noLocA $ HsLam noExtField
(MG { mg_alts = noLocA [mkSimpleMatch
LambdaExpr
[mfix_pat] body]
, mg_ext = MatchGroupTc [unrestricted tup_ty] body_ty
, mg_origin = Generated })
mfix_pat = noLocA $ LazyPat noExtField $ mkBigLHsPatTupId rec_tup_pats
body = noLocA $ HsDo body_ty
ctx (noLocA (rec_stmts ++ [ret_stmt]))
ret_app = nlHsSyntaxApps return_op [mkBigLHsTupId rets]
ret_stmt = noLocA $ mkLastStmt ret_app
go _ (ParStmt {}) _ = panic "dsDo ParStmt"
go _ (TransStmt {}) _ = panic "dsDo TransStmt"
dsHsVar :: Id -> DsM CoreExpr
dsHsVar var
= return (varToCoreExpr var)
dsHsConLike :: ConLike -> DsM CoreExpr
dsHsConLike (RealDataCon dc)
= return (varToCoreExpr (dataConWrapId dc))
dsHsConLike (PatSynCon ps)
| Just (builder_name, _, add_void) <- patSynBuilder ps
= do { builder_id <- dsLookupGlobalId builder_name
; return (if add_void
then mkCoreApp (text "dsConLike" <+> ppr ps)
(Var builder_id) (Var voidPrimId)
else Var builder_id) }
| otherwise
= pprPanic "dsConLike" (ppr ps)
dsConLike :: ConLike -> [TcTyVar] -> [Scaled Type] -> DsM CoreExpr
dsConLike con tvs tys
= do { ds_con <- dsHsConLike con
; ids <- newSysLocalsDs tys
; return (mkLams tvs $
mkLams ids $
ds_con `mkTyApps` mkTyVarTys tvs
`mkVarApps` drop_stupid ids) }
where
drop_stupid = dropList (conLikeStupidTheta con)
warnDiscardedDoBindings :: LHsExpr GhcTc -> Type -> DsM ()
warnDiscardedDoBindings rhs rhs_ty
| Just (m_ty, elt_ty) <- tcSplitAppTy_maybe rhs_ty
= do { warn_unused <- woptM Opt_WarnUnusedDoBind
; warn_wrong <- woptM Opt_WarnWrongDoBind
; when (warn_unused || warn_wrong) $
do { fam_inst_envs <- dsGetFamInstEnvs
; let norm_elt_ty = topNormaliseType fam_inst_envs elt_ty
; if warn_unused && not (isUnitTy norm_elt_ty)
then diagnosticDs (DsUnusedDoBind rhs elt_ty)
else
when warn_wrong $
case tcSplitAppTy_maybe norm_elt_ty of
Just (elt_m_ty, _)
| m_ty `eqType` topNormaliseType fam_inst_envs elt_m_ty
-> diagnosticDs (DsWrongDoBind rhs elt_ty)
_ -> return () } }
| otherwise
= return ()
dsHsWrapped :: HsExpr GhcTc -> DsM CoreExpr
dsHsWrapped orig_hs_expr
= go idHsWrapper orig_hs_expr
where
go wrap (HsPar _ _ (L _ hs_e) _)
= go wrap hs_e
go wrap1 (XExpr (WrapExpr (HsWrap wrap2 hs_e)))
= go (wrap1 <.> wrap2) hs_e
go wrap (HsAppType ty (L _ hs_e) _)
= go (wrap <.> WpTyApp ty) hs_e
go wrap (HsVar _ (L _ var))
= do { wrap' <- dsHsWrapper wrap
; let expr = wrap' (varToCoreExpr var)
ty = exprType expr
; dflags <- getDynFlags
; warnAboutIdentities dflags var ty
; return expr }
go wrap hs_e
= do { wrap' <- dsHsWrapper wrap
; addTyCs FromSource (hsWrapDictBinders wrap) $
do { e <- dsExpr hs_e
; return (wrap' e) } }