combineGRHSMatchResults,
combineMatchResults,
- dsExprToAtom,
+ dsExprToAtom, SYN_IE(DsCoreArg),
mkCoAlgCaseMatchResult,
- mkAppDs, mkConDs, mkPrimDs,
+ mkAppDs, mkConDs, mkPrimDs, mkErrorAppDs,
mkCoLetsMatchResult,
mkCoPrimCaseMatchResult,
mkFailurePair,
mkSelectorBinds,
mkTupleBind,
mkTupleExpr,
- selectMatchVars
+ mkTupleSelector,
+ selectMatchVars,
+ showForErr
) where
-import Ubiq
-import DsLoop ( match, matchSimply )
+IMP_Ubiq()
+IMPORT_DELOOPER(DsLoop) ( match, matchSimply )
-import HsSyn ( HsExpr(..), OutPat(..), HsLit(..),
- Match, HsBinds, Stmt, Qual, PolyType, ArithSeqInfo )
-import TcHsSyn ( TypecheckedPat(..) )
-import DsHsSyn ( outPatType )
+import HsSyn ( HsExpr(..), OutPat(..), HsLit(..), Fixity,
+ Match, HsBinds, Stmt, DoOrListComp, HsType, ArithSeqInfo )
+import TcHsSyn ( SYN_IE(TypecheckedPat) )
+import DsHsSyn ( outPatType, collectTypedPatBinders )
+import CmdLineOpts ( opt_PprUserLength )
import CoreSyn
import DsMonad
-import CoreUtils ( coreExprType, escErrorMsg, mkCoreIfThenElse, mkErrorApp )
-import PrelInfo ( stringTy )
-import Id ( idType, getInstantiatedDataConSig, mkTupleCon,
- DataCon(..), DictVar(..), Id(..), GenId )
-import TyCon ( mkTupleTyCon )
-import Type ( mkTyVarTys, mkRhoTy, mkFunTys, isUnboxedType,
- applyTyCon, getAppDataTyCon
+import CoreUtils ( coreExprType, mkCoreIfThenElse )
+import PrelVals ( iRREFUT_PAT_ERROR_ID, voidId )
+import Pretty ( Doc, hcat, text )
+import Id ( idType, dataConArgTys,
+-- pprId{-ToDo:rm-},
+ SYN_IE(DataCon), SYN_IE(DictVar), SYN_IE(Id), GenId )
+import Literal ( Literal(..) )
+import PprType ( GenType, GenTyVar )
+import PrimOp ( PrimOp )
+import TyCon ( isNewTyCon, tyConDataCons )
+import Type ( mkTyVarTys, mkRhoTy, mkForAllTys, mkFunTy,
+ mkTheta, isUnboxedType, applyTyCon, getAppTyCon,
+ GenType {- instances -}, SYN_IE(Type)
)
-import UniqSet ( mkUniqSet, minusUniqSet, uniqSetToList, UniqSet(..) )
-import Util ( panic, assertPanic )
+import TyVar ( GenTyVar {- instances -}, SYN_IE(TyVar) )
+import TysPrim ( voidTy )
+import TysWiredIn ( tupleTyCon, unitDataCon, tupleCon )
+import UniqSet ( mkUniqSet, minusUniqSet, uniqSetToList, SYN_IE(UniqSet) )
+import Util ( panic, assertPanic{-, pprTrace ToDo:rm-} )
+import Unique ( Unique )
+import Usage ( SYN_IE(UVar) )
+import SrcLoc ( SrcLoc {- instance Outputable -} )
+
+import Outputable
-quantifyTy = panic "DsUtils.quantifyTy"
-splitDictType = panic "DsUtils.splitDictType"
-mkCoTyApps = panic "DsUtils.mkCoTyApps"
\end{code}
+
+%************************************************************************
+%* *
+%* Selecting match variables
+%* *
+%************************************************************************
+
+We're about to match against some patterns. We want to make some
+@Ids@ to use as match variables. If a pattern has an @Id@ readily at
+hand, which should indeed be bound to the pattern as a whole, then use it;
+otherwise, make one up.
+
+\begin{code}
+selectMatchVars :: [TypecheckedPat] -> DsM [Id]
+selectMatchVars pats
+ = mapDs var_from_pat_maybe pats
+ where
+ var_from_pat_maybe (VarPat var) = returnDs var
+ var_from_pat_maybe (AsPat var pat) = returnDs var
+ var_from_pat_maybe (LazyPat pat) = var_from_pat_maybe pat
+ var_from_pat_maybe other_pat
+ = newSysLocalDs (outPatType other_pat) -- OK, better make up one...
+\end{code}
+
+
%************************************************************************
%* *
%* type synonym EquationInfo and access functions for its pieces *
mkCoAlgCaseMatchResult :: Id -- Scrutinee
-> [(DataCon, [Id], MatchResult)] -- Alternatives
-> DsM MatchResult
+
mkCoAlgCaseMatchResult var alts
+ | isNewTyCon tycon -- newtype case; use a let
+ = ASSERT( newtype_sanity )
+ returnDs (mkCoLetsMatchResult [coercion_bind] match_result)
+
+ | otherwise -- datatype case
= -- Find all the constructors in the type which aren't
-- explicitly mentioned in the alternatives:
case un_mentioned_constructors of
-- We need to build new locals for the args of the constructor,
-- and figuring out their types is somewhat tiresome.
let
- (_,arg_tys,_) = getInstantiatedDataConSig con tycon_arg_tys
+ arg_tys = dataConArgTys con tycon_arg_tys
in
newSysLocalsDs arg_tys `thenDs` \ arg_ids ->
(mk_case alts (\fail_expr -> BindDefault wild fail_expr))
cxt1)
where
+ -- Common stuff
scrut_ty = idType var
- (tycon, tycon_arg_tys, data_cons) = getAppDataTyCon scrut_ty
+ (tycon, tycon_arg_tys) = --pprTrace "CoAlgCase:" (pprType PprDebug scrut_ty) $
+ getAppTyCon scrut_ty
+
+ -- Stuff for newtype
+ (con_id, arg_ids, match_result) = head alts
+ arg_id = head arg_ids
+ coercion_bind = NonRec arg_id (Coerce (CoerceOut con_id)
+ (idType arg_id)
+ (Var var))
+ newtype_sanity = null (tail alts) && null (tail arg_ids)
+
+ -- Stuff for data types
+ data_cons = tyConDataCons tycon
un_mentioned_constructors
= uniqSetToList (mkUniqSet data_cons `minusUniqSet` mkUniqSet [ con | (con, _, _) <- alts] )
%************************************************************************
\begin{code}
-dsExprToAtom :: CoreExpr -- The argument expression
+dsExprToAtom :: DsCoreArg -- The argument expression
-> (CoreArg -> DsM CoreExpr) -- Something taking the argument *atom*,
-- and delivering an expression E
-> DsM CoreExpr -- Either E or let x=arg-expr in E
-dsExprToAtom (Var v) continue_with = continue_with (VarArg v)
-dsExprToAtom (Lit v) continue_with = continue_with (LitArg v)
+dsExprToAtom (UsageArg u) continue_with = continue_with (UsageArg u)
+dsExprToAtom (TyArg t) continue_with = continue_with (TyArg t)
+dsExprToAtom (LitArg l) continue_with = continue_with (LitArg l)
+
+dsExprToAtom (VarArg (Var v)) continue_with = continue_with (VarArg v)
+dsExprToAtom (VarArg (Lit v)) continue_with = continue_with (LitArg v)
-dsExprToAtom arg_expr continue_with
+dsExprToAtom (VarArg arg_expr) continue_with
= let
ty = coreExprType arg_expr
in
else Let (NonRec arg_id arg_expr) body
)
-dsExprsToAtoms :: [CoreExpr]
+dsExprsToAtoms :: [DsCoreArg]
-> ([CoreArg] -> DsM CoreExpr)
-> DsM CoreExpr
-dsExprsToAtoms [] continue_with
- = continue_with []
+dsExprsToAtoms [] continue_with = continue_with []
dsExprsToAtoms (arg:args) continue_with
= dsExprToAtom arg $ \ arg_atom ->
%* *
%************************************************************************
-Plumb the desugarer's @UniqueSupply@ in/out of the @UniqSupply@ monad
-world.
\begin{code}
-mkAppDs :: CoreExpr -> [Type] -> [CoreExpr] -> DsM CoreExpr
-mkConDs :: Id -> [Type] -> [CoreExpr] -> DsM CoreExpr
-mkPrimDs :: PrimOp -> [Type] -> [CoreExpr] -> DsM CoreExpr
+type DsCoreArg = GenCoreArg CoreExpr{-NB!-} TyVar UVar
+
+mkAppDs :: CoreExpr -> [DsCoreArg] -> DsM CoreExpr
+mkConDs :: Id -> [DsCoreArg] -> DsM CoreExpr
+mkPrimDs :: PrimOp -> [DsCoreArg] -> DsM CoreExpr
-mkAppDs fun tys arg_exprs
- = dsExprsToAtoms arg_exprs $ \ vals ->
- returnDs (mkApp fun [] tys vals)
+mkAppDs fun args
+ = dsExprsToAtoms args $ \ atoms ->
+ returnDs (mkGenApp fun atoms)
-mkConDs con tys arg_exprs
- = dsExprsToAtoms arg_exprs $ \ vals ->
- returnDs (mkCon con [] tys vals)
+mkConDs con args
+ = dsExprsToAtoms args $ \ atoms ->
+ returnDs (Con con atoms)
-mkPrimDs op tys arg_exprs
- = dsExprsToAtoms arg_exprs $ \ vals ->
- returnDs (mkPrim op [] tys vals)
+mkPrimDs op args
+ = dsExprsToAtoms args $ \ atoms ->
+ returnDs (Prim op atoms)
+\end{code}
+
+\begin{code}
+showForErr :: Outputable a => a -> String -- Boring but useful
+showForErr thing = show (ppr PprQuote thing)
+
+mkErrorAppDs :: Id -- The error function
+ -> Type -- Type to which it should be applied
+ -> String -- The error message string to pass
+ -> DsM CoreExpr
+
+mkErrorAppDs err_id ty msg
+ = getSrcLocDs `thenDs` \ src_loc ->
+ let
+ full_msg = show (hcat [ppr (PprForUser opt_PprUserLength) src_loc, text "|", text msg])
+ msg_lit = NoRepStr (_PK_ full_msg)
+ in
+ returnDs (mkApp (Var err_id) [] [ty] [LitArg msg_lit])
\end{code}
%************************************************************************
expressions.
\begin{code}
-mkSelectorBinds :: [TyVar] -- Variables wrt which the pattern is polymorphic
- -> TypecheckedPat -- The pattern
- -> [(Id,Id)] -- Monomorphic and polymorphic binders for
- -- the pattern
- -> CoreExpr -- Expression to which the pattern is bound
+mkSelectorBinds :: TypecheckedPat -- The pattern
+ -> CoreExpr -- Expression to which the pattern is bound
-> DsM [(Id,CoreExpr)]
-mkSelectorBinds tyvars pat locals_and_globals val_expr
- = getSrcLocDs `thenDs` \ (src_file, src_line) ->
-
- if is_simple_tuple_pat pat then
- mkTupleBind tyvars [] locals_and_globals val_expr
- else
- newSysLocalDs stringTy `thenDs` \ str_var -> -- to hold the string
- let
- src_loc_str = escErrorMsg ('"' : src_file) ++ "%l" ++ src_line
- error_string = src_loc_str ++ "%~" --> ": pattern-match failed on an irrefutable pattern"
- error_msg = mkErrorApp res_ty str_var error_string
- in
- matchSimply val_expr pat res_ty local_tuple error_msg `thenDs` \ tuple_expr ->
- mkTupleBind tyvars [] locals_and_globals tuple_expr
+mkSelectorBinds (VarPat v) val_expr
+ = returnDs [(v, val_expr)]
+
+mkSelectorBinds pat val_expr
+ | is_simple_tuple_pat pat
+ = mkTupleBind binders val_expr
+
+ | otherwise
+ = mkErrorAppDs iRREFUT_PAT_ERROR_ID res_ty pat_string `thenDs` \ error_msg ->
+ matchSimply val_expr pat res_ty local_tuple error_msg `thenDs` \ tuple_expr ->
+ mkTupleBind binders tuple_expr
+
where
- locals = [local | (local, _) <- locals_and_globals]
- local_tuple = mkTupleExpr locals
+ binders = collectTypedPatBinders pat
+ local_tuple = mkTupleExpr binders
res_ty = coreExprType local_tuple
is_simple_tuple_pat (TuplePat ps) = all is_var_pat ps
is_var_pat (VarPat v) = True
is_var_pat other = False -- Even wild-card patterns aren't acceptable
-\end{code}
-
-We're about to match against some patterns. We want to make some
-@Ids@ to use as match variables. If a pattern has an @Id@ readily at
-hand, which should indeed be bound to the pattern as a whole, then use it;
-otherwise, make one up.
-\begin{code}
-selectMatchVars :: [TypecheckedPat] -> DsM [Id]
-selectMatchVars pats
- = mapDs var_from_pat_maybe pats
- where
- var_from_pat_maybe (VarPat var) = returnDs var
- var_from_pat_maybe (AsPat var pat) = returnDs var
- var_from_pat_maybe (LazyPat pat) = var_from_pat_maybe pat
- var_from_pat_maybe other_pat
- = newSysLocalDs (outPatType other_pat) -- OK, better make up one...
-\end{code}
-
-\begin{code}
-mkTupleBind :: [TyVar] -- Abstract wrt these...
- -> [DictVar] -- ... and these
-
- -> [(Id, Id)] -- Local, global pairs, equal in number
- -- to the size of the tuple. The types
- -- of the globals is the generalisation of
- -- the corresp local, wrt the tyvars and dicts
-
- -> CoreExpr -- Expr whose value is a tuple; the expression
- -- may mention the tyvars and dicts
- -> DsM [(Id, CoreExpr)] -- Bindings for the globals
+ pat_string = show (ppr (PprForUser opt_PprUserLength) pat)
\end{code}
-The general call is
-\begin{verbatim}
- mkTupleBind tyvars dicts [(l1,g1), ..., (ln,gn)] tup_expr
-\end{verbatim}
-If $n=1$, the result is:
-\begin{verbatim}
- g1 = /\ tyvars -> \ dicts -> rhs
-\end{verbatim}
-Otherwise, the result is:
-\begin{verbatim}
- tup = /\ tyvars -> \ dicts -> tup_expr
- g1 = /\ tyvars -> \ dicts -> case (tup tyvars dicts) of
- (l1, ..., ln) -> l1
- ...etc...
-\end{verbatim}
\begin{code}
-mkTupleBind tyvars dicts [(local,global)] tuple_expr
- = returnDs [(global, mkLam tyvars dicts tuple_expr)]
-\end{code}
+mkTupleBind :: [Id] -- Names of tuple components
+ -> CoreExpr -- Expr whose value is a tuple of correct type
+ -> DsM [(Id, CoreExpr)] -- Bindings for the globals
-The general case:
-\begin{code}
-mkTupleBind tyvars dicts local_global_prs tuple_expr
- = newSysLocalDs tuple_var_ty `thenDs` \ tuple_var ->
+mkTupleBind [local] tuple_expr
+ = returnDs [(local, tuple_expr)]
- zipWithDs (mk_selector (Var tuple_var))
- local_global_prs
- [(0::Int) .. (length local_global_prs - 1)]
- `thenDs` \ tup_selectors ->
- returnDs (
- (tuple_var, mkLam tyvars dicts tuple_expr)
- : tup_selectors
- )
- where
- locals, globals :: [Id]
- locals = [local | (local,global) <- local_global_prs]
- globals = [global | (local,global) <- local_global_prs]
-
- no_of_binders = length local_global_prs
- tyvar_tys = mkTyVarTys tyvars
-
- tuple_var_ty :: Type
- tuple_var_ty
- = case (quantifyTy tyvars (mkRhoTy theta
- (applyTyCon (mkTupleTyCon no_of_binders)
- (map idType locals)))) of
- (_{-tossed templates-}, ty) -> ty
- where
- theta = map (splitDictType . idType) dicts
-
- mk_selector :: CoreExpr -> (Id, Id) -> Int -> DsM (Id, CoreExpr)
-
- mk_selector tuple_var_expr (local, global) which_local
- = mapDs duplicateLocalDs locals{-the whole bunch-} `thenDs` \ binders ->
- let
- selected = binders !! which_local
- in
- returnDs (
- global,
- mkLam tyvars dicts (
- mkTupleSelector (mkApp_XX (mkCoTyApps tuple_var_expr tyvar_tys) dicts)
- binders selected)
- )
-
-mkApp_XX :: CoreExpr -> [Id] -> CoreExpr
-mkApp_XX expr [] = expr
-mkApp_XX expr (id:ids) = mkApp_XX (App expr (VarArg id)) ids
+mkTupleBind locals tuple_expr
+ = newSysLocalDs (coreExprType tuple_expr) `thenDs` \ tuple_var ->
+ let
+ mk_bind local = (local, mkTupleSelector locals local (Var tuple_var))
+ in
+ returnDs ( (tuple_var, tuple_expr) :
+ map mk_bind locals )
\end{code}
-
@mkTupleExpr@ builds a tuple; the inverse to @mkTupleSelector@. If it
has only one element, it is the identity function.
\begin{code}
mkTupleExpr :: [Id] -> CoreExpr
-mkTupleExpr [] = Con (mkTupleCon 0) []
+mkTupleExpr [] = Con unitDataCon []
mkTupleExpr [id] = Var id
-mkTupleExpr ids = mkCon (mkTupleCon (length ids))
+mkTupleExpr ids = mkCon (tupleCon (length ids))
[{-usages-}]
(map idType ids)
[ VarArg i | i <- ids ]
just the identity.
\begin{code}
-mkTupleSelector :: CoreExpr -- Scrutinee
- -> [Id] -- The tuple args
+mkTupleSelector :: [Id] -- The tuple args
-> Id -- The selected one
+ -> CoreExpr -- Scrutinee
-> CoreExpr
-mkTupleSelector expr [] the_var = panic "mkTupleSelector"
+mkTupleSelector [] the_var scrut = panic "mkTupleSelector"
-mkTupleSelector expr [var] should_be_the_same_var
+mkTupleSelector [var] should_be_the_same_var scrut
= ASSERT(var == should_be_the_same_var)
- expr
+ scrut
-mkTupleSelector expr vars the_var
- = Case expr (AlgAlts [(mkTupleCon arity, vars, Var the_var)]
+mkTupleSelector vars the_var scrut
+ = Case scrut (AlgAlts [(tupleCon arity, vars, Var the_var)]
NoDefault)
where
arity = length vars
only boxed types can be let-bound, we just turn the fail into a function
for the primitive case:
\begin{verbatim}
- let fail.33 :: () -> Int#
+ let fail.33 :: Void -> Int#
fail.33 = \_ -> error "Help"
in
case x of
p1 -> ...
- p2 -> fail.33 ()
- p3 -> fail.33 ()
+ p2 -> fail.33 void
+ p3 -> fail.33 void
p4 -> ...
\end{verbatim}
-- applied to unit tuple
mkFailurePair ty
| isUnboxedType ty
- = newFailLocalDs (mkFunTys [unit_ty] ty) `thenDs` \ fail_fun_var ->
- newSysLocalDs unit_ty `thenDs` \ fail_fun_arg ->
+ = newFailLocalDs (voidTy `mkFunTy` ty) `thenDs` \ fail_fun_var ->
+ newSysLocalDs voidTy `thenDs` \ fail_fun_arg ->
returnDs (\ body ->
NonRec fail_fun_var (Lam (ValBinder fail_fun_arg) body),
- App (Var fail_fun_var) (VarArg unit_id))
+ App (Var fail_fun_var) (VarArg voidId))
| otherwise
= newFailLocalDs ty `thenDs` \ fail_var ->
returnDs (\ body -> NonRec fail_var body, Var fail_var)
+\end{code}
+
-unit_id :: Id -- out here to avoid CAF (sigh)
-unit_id = mkTupleCon 0
-unit_ty :: Type
-unit_ty = idType unit_id
-\end{code}
projects / ghc-hetmet.git / blobdiff