X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FdeSugar%2FDsExpr.lhs;h=ea1eeebea2fdf654c4b6f477c3612f32be5d4053;hb=074d99bd864680f896b671fa354fcca6be77ae12;hp=2b26091ee4944eb8b45919ab9e4f30b4da03d54d;hpb=55db5c327ad5931daecb84078c7abffb27bed1d8;p=ghc-hetmet.git diff --git a/ghc/compiler/deSugar/DsExpr.lhs b/ghc/compiler/deSugar/DsExpr.lhs index 2b26091..ea1eeeb 100644 --- a/ghc/compiler/deSugar/DsExpr.lhs +++ b/ghc/compiler/deSugar/DsExpr.lhs @@ -15,42 +15,45 @@ import HsSyn ( failureFreePat, mkSimpleMatch ) import TcHsSyn ( TypecheckedHsExpr, TypecheckedHsBinds, - TypecheckedStmt, - maybeBoxedPrimType - + TypecheckedStmt ) import CoreSyn +import PprCore ( {- instance Outputable Expr -} ) +import CoreUtils ( exprType, mkIfThenElse, bindNonRec ) import DsMonad -import DsBinds ( dsMonoBinds ) +import DsBinds ( dsMonoBinds, AutoScc(..) ) import DsGRHSs ( dsGuarded ) -import DsCCall ( dsCCall ) +import DsCCall ( dsCCall, resultWrapper ) import DsListComp ( dsListComp ) -import DsUtils ( mkErrorAppDs ) +import DsUtils ( mkErrorAppDs, mkDsLets, mkConsExpr, mkNilExpr ) import Match ( matchWrapper, matchSimply ) -import CoreUtils ( coreExprType ) import CostCentre ( mkUserCC ) import FieldLabel ( FieldLabel ) import Id ( Id, idType, recordSelectorFieldLabel ) -import Const ( Con(..) ) -import DataCon ( DataCon, dataConId, dataConTyCon, dataConArgTys, dataConFieldLabels ) -import Const ( mkMachInt, Literal(..), mkStrLit ) -import PrelVals ( rEC_CON_ERROR_ID, rEC_UPD_ERROR_ID, iRREFUT_PAT_ERROR_ID ) +import DataCon ( DataCon, dataConWrapId, dataConTyCon, dataConArgTys, dataConFieldLabels ) +import PrelInfo ( rEC_CON_ERROR_ID, rEC_UPD_ERROR_ID, iRREFUT_PAT_ERROR_ID, addr2IntegerId ) import TyCon ( isNewTyCon ) import DataCon ( isExistentialDataCon ) +import Literal ( Literal(..), inIntRange ) import Type ( splitFunTys, mkTyConApp, - splitAlgTyConApp, splitTyConApp_maybe, + splitAlgTyConApp, splitAlgTyConApp_maybe, splitTyConApp_maybe, + isNotUsgTy, unUsgTy, splitAppTy, isUnLiftedType, Type ) import TysWiredIn ( tupleCon, unboxedTupleCon, - consDataCon, listTyCon, mkListTy, - charDataCon, charTy, stringTy + listTyCon, mkListTy, + charDataCon, charTy, stringTy, + smallIntegerDataCon, isIntegerTy ) import BasicTypes ( RecFlag(..) ) import Maybes ( maybeToBool ) +import Unique ( Uniquable(..), ratioTyConKey ) import Util ( zipEqual, zipWithEqual ) import Outputable + +import Ratio ( numerator, denominator ) \end{code} @@ -60,14 +63,14 @@ import Outputable %* * %************************************************************************ -@dsLet@ is a match-result transformer, taking the MatchResult for the body +@dsLet@ is a match-result transformer, taking the @MatchResult@ for the body and transforming it into one for the let-bindings enclosing the body. This may seem a bit odd, but (source) let bindings can contain unboxed binds like - +\begin{verbatim} C x# = e - +\end{verbatim} This must be transformed to a case expression and, if the type has more than one constructor, may fail. @@ -82,7 +85,9 @@ dsLet (ThenBinds b1 b2) body dsLet b1 body' -- Special case for bindings which bind unlifted variables -dsLet (MonoBind (AbsBinds [] [] binder_triples (PatMonoBind pat grhss loc)) sigs is_rec) body +-- Silently ignore INLINE pragmas... +dsLet (MonoBind (AbsBinds [] [] binder_triples inlines + (PatMonoBind pat grhss loc)) sigs is_rec) body | or [isUnLiftedType (idType g) | (_, g, l) <- binder_triples] = ASSERT (case is_rec of {NonRecursive -> True; other -> False}) putSrcLocDs loc $ @@ -92,19 +97,18 @@ dsLet (MonoBind (AbsBinds [] [] binder_triples (PatMonoBind pat grhss loc)) sigs bind (tyvars, g, l) body = ASSERT( null tyvars ) bindNonRec g (Var l) body in - mkErrorAppDs iRREFUT_PAT_ERROR_ID result_ty (showSDoc (ppr pat)) `thenDs` \ error_expr -> + mkErrorAppDs iRREFUT_PAT_ERROR_ID result_ty (showSDoc (ppr pat)) + `thenDs` \ error_expr -> matchSimply rhs PatBindMatch pat body' error_expr where - result_ty = coreExprType body + result_ty = exprType body -- Ordinary case for bindings dsLet (MonoBind binds sigs is_rec) body - = dsMonoBinds False binds [] `thenDs` \ prs -> + = dsMonoBinds NoSccs binds [] `thenDs` \ prs -> case is_rec of Recursive -> returnDs (Let (Rec prs) body) - NonRecursive -> returnDs (foldr mk_let body prs) - where - mk_let (bndr,rhs) body = Let (NonRec bndr rhs) body + NonRecursive -> returnDs (mkDsLets [NonRec b r | (b,r) <- prs] body) \end{code} %************************************************************************ @@ -117,6 +121,7 @@ dsLet (MonoBind binds sigs is_rec) body dsExpr :: TypecheckedHsExpr -> DsM CoreExpr dsExpr e@(HsVar var) = returnDs (Var var) +dsExpr e@(HsIPVar var) = returnDs (Var var) \end{code} %************************************************************************ @@ -125,18 +130,16 @@ dsExpr e@(HsVar var) = returnDs (Var var) %* * %************************************************************************ -We give int/float literals type Integer and Rational, respectively. +We give int/float literals type @Integer@ and @Rational@, respectively. The typechecker will (presumably) have put \tr{from{Integer,Rational}s} around them. -ToDo: put in range checks for when converting "i" +ToDo: put in range checks for when converting ``@i@'' (or should that be in the typechecker?) For numeric literals, we try to detect there use at a standard type -(Int, Float, etc.) are directly put in the right constructor. +(@Int@, @Float@, etc.) are directly put in the right constructor. [NB: down with the @App@ conversion.] -Otherwise, we punt, putting in a "NoRep" Core literal (where the -representation decisions are delayed)... See also below where we look for @DictApps@ for \tr{plusInt}, etc. @@ -149,79 +152,49 @@ dsExpr (HsLitOut (HsString s) _) = let the_char = mkConApp charDataCon [mkLit (MachChar (_HEAD_ s))] the_nil = mkNilExpr charTy - the_cons = mkConApp consDataCon [Type charTy, the_char, the_nil] + the_cons = mkConsExpr charTy the_char the_nil in returnDs the_cons -- "_" => build (\ c n -> c 'c' n) -- LATER --- "str" ==> build (\ c n -> foldr charTy T c n "str") - -{- LATER: dsExpr (HsLitOut (HsString str) _) - = newTyVarsDs [alphaTyVar] `thenDs` \ [new_tyvar] -> - let - new_ty = mkTyVarTy new_tyvar - in - newSysLocalsDs [ - charTy `mkFunTy` (new_ty `mkFunTy` new_ty), - new_ty, - mkForallTy [alphaTyVar] - ((charTy `mkFunTy` (alphaTy `mkFunTy` alphaTy)) - `mkFunTy` (alphaTy `mkFunTy` alphaTy)) - ] `thenDs` \ [c,n,g] -> - returnDs (mkBuild charTy new_tyvar c n g ( - foldl App - (CoTyApp (CoTyApp (Var foldrId) charTy) new_ty) *** ensure non-prim type *** - [VarArg c,VarArg n,LitArg (NoRepStr str)])) --} - --- otherwise, leave it as a NoRepStr; --- the Core-to-STG pass will wrap it in an application of "unpackCStringId". - -dsExpr (HsLitOut (HsString str) _) - = returnDs (mkLit (NoRepStr str stringTy)) + = returnDs (mkStringLitFS str) dsExpr (HsLitOut (HsLitLit str) ty) - = case (maybeBoxedPrimType ty) of - Just (boxing_data_con, prim_ty) -> - returnDs ( mkConApp boxing_data_con [mkLit (MachLitLit str prim_ty)] ) - _ -> - pprError "ERROR:" - (vcat - [ hcat [ text "Cannot see data constructor of ``literal-literal''s type: " - , text "value:", quotes (quotes (ptext str)) - , text "; type: ", ppr ty - ] - , text "Try compiling with -fno-prune-tydecls." - ]) - + = ASSERT( maybeToBool maybe_ty ) + returnDs (wrap_fn (mkLit (MachLitLit str rep_ty))) where - (data_con, prim_ty) - = case (maybeBoxedPrimType ty) of - Just (boxing_data_con, prim_ty) -> (boxing_data_con, prim_ty) - Nothing - -> pprPanic "ERROR: ``literal-literal'' not a single-constructor type: " - (hcat [ptext str, text "; type: ", ppr ty]) + (maybe_ty, wrap_fn) = resultWrapper ty + Just rep_ty = maybe_ty dsExpr (HsLitOut (HsInt i) ty) - = returnDs (mkLit (NoRepInteger i ty)) + = returnDs (mkIntegerLit i) + dsExpr (HsLitOut (HsFrac r) ty) - = returnDs (mkLit (NoRepRational r ty)) + = returnDs (mkConApp ratio_data_con [Type integer_ty, + mkIntegerLit (numerator r), + mkIntegerLit (denominator r)]) + where + (ratio_data_con, integer_ty) + = case (splitAlgTyConApp_maybe ty) of + Just (tycon, [i_ty], [con]) + -> ASSERT(isIntegerTy i_ty && getUnique tycon == ratioTyConKey) + (con, i_ty) + + _ -> (panic "ratio_data_con", panic "integer_ty") + + -- others where we know what to do: -dsExpr (HsLitOut (HsIntPrim i) _) - | (i >= toInteger minInt && i <= toInteger maxInt) - = returnDs (mkLit (mkMachInt i)) - | otherwise - = error ("ERROR: Int constant " ++ show i ++ out_of_range_msg) +dsExpr (HsLitOut (HsIntPrim i) _) + = returnDs (mkIntLit i) dsExpr (HsLitOut (HsFloatPrim f) _) = returnDs (mkLit (MachFloat f)) - -- ToDo: range checking needed! dsExpr (HsLitOut (HsDoublePrim d) _) = returnDs (mkLit (MachDouble d)) @@ -274,9 +247,6 @@ will sort it out. dsExpr (OpApp e1 op _ e2) = dsExpr op `thenDs` \ core_op -> -- for the type of y, we need the type of op's 2nd argument - let - (x_ty:y_ty:_, _) = splitFunTys (coreExprType core_op) - in dsExpr e1 `thenDs` \ x_core -> dsExpr e2 `thenDs` \ y_core -> returnDs (mkApps core_op [x_core, y_core]) @@ -285,7 +255,7 @@ dsExpr (SectionL expr op) = dsExpr op `thenDs` \ core_op -> -- for the type of y, we need the type of op's 2nd argument let - (x_ty:y_ty:_, _) = splitFunTys (coreExprType core_op) + (x_ty:y_ty:_, _) = splitFunTys (exprType core_op) in dsExpr expr `thenDs` \ x_core -> newSysLocalDs x_ty `thenDs` \ x_id -> @@ -299,7 +269,7 @@ dsExpr (SectionR op expr) = dsExpr op `thenDs` \ core_op -> -- for the type of x, we need the type of op's 2nd argument let - (x_ty:y_ty:_, _) = splitFunTys (coreExprType core_op) + (x_ty:y_ty:_, _) = splitFunTys (exprType core_op) in dsExpr expr `thenDs` \ y_core -> newSysLocalDs x_ty `thenDs` \ x_id -> @@ -308,38 +278,49 @@ dsExpr (SectionR op expr) returnDs (bindNonRec y_id y_core $ Lam x_id (mkApps core_op [Var x_id, Var y_id])) -dsExpr (CCall label args may_gc is_asm result_ty) +dsExpr (HsCCall lbl args may_gc is_asm result_ty) = mapDs dsExpr args `thenDs` \ core_args -> - dsCCall label core_args may_gc is_asm result_ty + dsCCall lbl core_args may_gc is_asm result_ty -- dsCCall does all the unboxification, etc. dsExpr (HsSCC cc expr) = dsExpr expr `thenDs` \ core_expr -> - getModuleAndGroupDs `thenDs` \ (mod_name, group_name) -> - returnDs (Note (SCC (mkUserCC cc mod_name group_name)) core_expr) + getModuleDs `thenDs` \ mod_name -> + returnDs (Note (SCC (mkUserCC cc mod_name)) core_expr) -- special case to handle unboxed tuple patterns. -dsExpr (HsCase discrim matches@[Match _ [TuplePat ps boxed] _ _] src_loc) - | not boxed && all var_pat ps +dsExpr (HsCase discrim matches src_loc) + | all ubx_tuple_match matches = putSrcLocDs src_loc $ - dsExpr discrim `thenDs` \ core_discrim -> - matchWrapper CaseMatch matches "case" `thenDs` \ ([discrim_var], matching_code) -> + dsExpr discrim `thenDs` \ core_discrim -> + matchWrapper CaseMatch matches "case" `thenDs` \ ([discrim_var], matching_code) -> case matching_code of Case (Var x) bndr alts | x == discrim_var -> returnDs (Case core_discrim bndr alts) _ -> panic ("dsExpr: tuple pattern:\n" ++ showSDoc (ppr matching_code)) + where + ubx_tuple_match (Match _ [TuplePat ps False{-unboxed-}] _ _) = True + ubx_tuple_match _ = False dsExpr (HsCase discrim matches src_loc) = putSrcLocDs src_loc $ - dsExpr discrim `thenDs` \ core_discrim -> - matchWrapper CaseMatch matches "case" `thenDs` \ ([discrim_var], matching_code) -> + dsExpr discrim `thenDs` \ core_discrim -> + matchWrapper CaseMatch matches "case" `thenDs` \ ([discrim_var], matching_code) -> returnDs (bindNonRec discrim_var core_discrim matching_code) dsExpr (HsLet binds body) = dsExpr body `thenDs` \ body' -> dsLet binds body' - + +dsExpr (HsWith expr binds) + = dsExpr expr `thenDs` \ expr' -> + foldlDs dsIPBind expr' binds + where + dsIPBind body (n, e) + = dsExpr e `thenDs` \ e' -> + returnDs (Let (NonRec n e') body) + dsExpr (HsDoOut do_or_lc stmts return_id then_id fail_id result_ty src_loc) | maybeToBool maybe_list_comp = -- Special case for list comprehensions @@ -371,8 +352,9 @@ dsExpr (HsIf guard_expr then_expr else_expr src_loc) \end{code} -Type lambda and application -~~~~~~~~~~~~~~~~~~~~~~~~~~~ +\noindent +\underline{\bf Type lambda and application} +% ~~~~~~~~~~~~~~~~~~~~~~~~~~~ \begin{code} dsExpr (TyLam tyvars expr) = dsExpr expr `thenDs` \ core_expr -> @@ -384,8 +366,9 @@ dsExpr (TyApp expr tys) \end{code} -Various data construction things -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +\noindent +\underline{\bf Various data construction things} +% ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ \begin{code} dsExpr (ExplicitListOut ty xs) = go xs @@ -395,26 +378,16 @@ dsExpr (ExplicitListOut ty xs) go [] = returnDs (mkNilExpr ty) go (x:xs) = dsExpr x `thenDs` \ core_x -> go xs `thenDs` \ core_xs -> - returnDs (mkConApp consDataCon [Type ty, core_x, core_xs]) + ASSERT( isNotUsgTy ty ) + returnDs (mkConsExpr ty core_x core_xs) dsExpr (ExplicitTuple expr_list boxed) = mapDs dsExpr expr_list `thenDs` \ core_exprs -> returnDs (mkConApp ((if boxed then tupleCon else unboxedTupleCon) (length expr_list)) - (map (Type . coreExprType) core_exprs ++ core_exprs)) - -dsExpr (HsCon con_id [ty] [arg]) - | isNewTyCon tycon - = dsExpr arg `thenDs` \ arg' -> - returnDs (Note (Coerce result_ty (coreExprType arg')) arg') - where - result_ty = mkTyConApp tycon [ty] - tycon = dataConTyCon con_id - -dsExpr (HsCon con_id tys args) - = mapDs dsExpr args `thenDs` \ args2 -> - returnDs (mkConApp con_id (map Type tys ++ args2)) + (map (Type . unUsgTy . exprType) core_exprs ++ core_exprs)) + -- the above unUsgTy is *required* -- KSW 1999-04-07 dsExpr (ArithSeqOut expr (From from)) = dsExpr expr `thenDs` \ expr2 -> @@ -441,28 +414,32 @@ dsExpr (ArithSeqOut expr (FromThenTo from thn two)) returnDs (mkApps expr2 [from2, thn2, two2]) \end{code} -Record construction and update -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +\noindent +\underline{\bf Record construction and update} +% ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ For record construction we do this (assuming T has three arguments) - +\begin{verbatim} T { op2 = e } ==> let err = /\a -> recConErr a T (recConErr t1 "M.lhs/230/op1") e (recConErr t1 "M.lhs/230/op3") - -recConErr then converts its arugment string into a proper message +\end{verbatim} +@recConErr@ then converts its arugment string into a proper message before printing it as - +\begin{verbatim} M.lhs, line 230: missing field op1 was evaluated +\end{verbatim} +We also handle @C{}@ as valid construction syntax for an unlabelled +constructor @C@, setting all of @C@'s fields to bottom. \begin{code} dsExpr (RecordConOut data_con con_expr rbinds) = dsExpr con_expr `thenDs` \ con_expr' -> let - (arg_tys, _) = splitFunTys (coreExprType con_expr') + (arg_tys, _) = splitFunTys (exprType con_expr') mk_arg (arg_ty, lbl) = case [rhs | (sel_id,rhs,_) <- rbinds, @@ -470,19 +447,27 @@ dsExpr (RecordConOut data_con con_expr rbinds) (rhs:rhss) -> ASSERT( null rhss ) dsExpr rhs [] -> mkErrorAppDs rEC_CON_ERROR_ID arg_ty (showSDoc (ppr lbl)) + unlabelled_bottom arg_ty = mkErrorAppDs rEC_CON_ERROR_ID arg_ty "" + + labels = dataConFieldLabels data_con in - mapDs mk_arg (zipEqual "dsExpr:RecordCon" arg_tys (dataConFieldLabels data_con)) `thenDs` \ con_args -> + + (if null labels + then mapDs unlabelled_bottom arg_tys + else mapDs mk_arg (zipEqual "dsExpr:RecordCon" arg_tys labels)) + `thenDs` \ con_args -> + returnDs (mkApps con_expr' con_args) \end{code} Record update is a little harder. Suppose we have the decl: - +\begin{verbatim} data T = T1 {op1, op2, op3 :: Int} | T2 {op4, op2 :: Int} | T3 - +\end{verbatim} Then we translate as follows: - +\begin{verbatim} r { op2 = e } ===> let op2 = e in @@ -490,63 +475,60 @@ Then we translate as follows: T1 op1 _ op3 -> T1 op1 op2 op3 T2 op4 _ -> T2 op4 op2 other -> recUpdError "M.lhs/230" - -It's important that we use the constructor Ids for T1, T2 etc on the -RHSs, and do not generate a Core Con directly, because the constructor +\end{verbatim} +It's important that we use the constructor Ids for @T1@, @T2@ etc on the +RHSs, and do not generate a Core constructor application directly, because the constructor might do some argument-evaluation first; and may have to throw away some dictionaries. \begin{code} dsExpr (RecordUpdOut record_expr record_out_ty dicts rbinds) - = dsExpr record_expr `thenDs` \ record_expr' -> + = getSrcLocDs `thenDs` \ src_loc -> + dsExpr record_expr `thenDs` \ record_expr' -> -- Desugar the rbinds, and generate let-bindings if -- necessary so that we don't lose sharing let - ds_rbind (sel_id, rhs, pun_flag) - = dsExpr rhs `thenDs` \ rhs' -> - returnDs (recordSelectorFieldLabel sel_id, rhs') - in - mapDs ds_rbind rbinds `thenDs` \ rbinds' -> - let - record_in_ty = coreExprType record_expr' + record_in_ty = exprType record_expr' (tycon, in_inst_tys, cons) = splitAlgTyConApp record_in_ty (_, out_inst_tys, _) = splitAlgTyConApp record_out_ty cons_to_upd = filter has_all_fields cons - -- initial_args are passed to every constructor - initial_args = map Type out_inst_tys ++ map Var dicts - mk_val_arg field old_arg_id - = case [rhs | (f, rhs) <- rbinds', field == f] of + = case [rhs | (sel_id, rhs, _) <- rbinds, + field == recordSelectorFieldLabel sel_id] of (rhs:rest) -> ASSERT(null rest) rhs - [] -> Var old_arg_id + [] -> HsVar old_arg_id mk_alt con = newSysLocalsDs (dataConArgTys con in_inst_tys) `thenDs` \ arg_ids -> + -- This call to dataConArgTys won't work for existentials let val_args = zipWithEqual "dsExpr:RecordUpd" mk_val_arg (dataConFieldLabels con) arg_ids - rhs = mkApps (mkApps (Var (dataConId con)) initial_args) val_args + rhs = foldl HsApp (DictApp (TyApp (HsVar (dataConWrapId con)) + out_inst_tys) + dicts) + val_args in - returnDs (DataCon con, arg_ids, rhs) - - mk_default - | length cons_to_upd == length cons - = returnDs [] - | otherwise - = mkErrorAppDs rEC_UPD_ERROR_ID record_out_ty "" `thenDs` \ err -> - returnDs [(DEFAULT, [], err)] + returnDs (mkSimpleMatch [ConPat con record_in_ty [] [] (map VarPat arg_ids)] + rhs + (Just record_out_ty) + src_loc) in -- Record stuff doesn't work for existentials ASSERT( all (not . isExistentialDataCon) cons ) - newSysLocalDs record_in_ty `thenDs` \ case_bndr -> - mapDs mk_alt cons_to_upd `thenDs` \ alts -> - mk_default `thenDs` \ deflt -> + -- It's important to generate the match with matchWrapper, + -- and the right hand sides with applications of the wrapper Id + -- so that everything works when we are doing fancy unboxing on the + -- constructor aguments. + mapDs mk_alt cons_to_upd `thenDs` \ alts -> + matchWrapper RecUpdMatch alts "record update" `thenDs` \ ([discrim_var], matching_code) -> + + returnDs (bindNonRec discrim_var record_expr' matching_code) - returnDs (Case record_expr' case_bndr (alts ++ deflt)) where has_all_fields :: DataCon -> Bool has_all_fields con_id @@ -556,8 +538,10 @@ dsExpr (RecordUpdOut record_expr record_out_ty dicts rbinds) ok (sel_id, _, _) = recordSelectorFieldLabel sel_id `elem` con_fields \end{code} -Dictionary lambda and application -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +\noindent +\underline{\bf Dictionary lambda and application} +% ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ @DictLam@ and @DictApp@ turn into the regular old things. (OLD:) @DictFunApp@ also becomes a curried application, albeit slightly more complicated; reminiscent of fully-applied constructors. @@ -583,8 +567,6 @@ dsExpr (ExprWithTySig _ _) = panic "dsExpr:ExprWithTySig" dsExpr (ArithSeqIn _) = panic "dsExpr:ArithSeqIn" #endif -out_of_range_msg -- ditto - = " out of range: [" ++ show minInt ++ ", " ++ show maxInt ++ "]\n" \end{code} %-------------------------------------------------------------------- @@ -611,17 +593,18 @@ dsDo do_or_lc stmts return_id then_id fail_id result_ty go (GuardStmt expr locn : stmts) = do_expr expr locn `thenDs` \ expr2 -> go stmts `thenDs` \ rest -> - let msg = "Pattern match failure in do expression, " ++ showSDoc (ppr locn) in + let msg = ASSERT( isNotUsgTy b_ty ) + "Pattern match failure in do expression, " ++ showSDoc (ppr locn) in returnDs (mkIfThenElse expr2 rest (App (App (Var fail_id) (Type b_ty)) - (mkLit (mkStrLit msg stringTy)))) + (mkStringLit msg))) go (ExprStmt expr locn : stmts) = do_expr expr locn `thenDs` \ expr2 -> let - (_, a_ty) = splitAppTy (coreExprType expr2) -- Must be of form (m a) + (_, a_ty) = splitAppTy (exprType expr2) -- Must be of form (m a) in if null stmts then returnDs expr2 @@ -639,11 +622,15 @@ dsDo do_or_lc stmts return_id then_id fail_id result_ty = putSrcLocDs locn $ dsExpr expr `thenDs` \ expr2 -> let - (_, a_ty) = splitAppTy (coreExprType expr2) -- Must be of form (m a) - fail_expr = HsApp (TyApp (HsVar fail_id) [b_ty]) (HsLitOut (HsString (_PK_ msg)) stringTy) - msg = "Pattern match failure in do expression, " ++ showSDoc (ppr locn) + (_, a_ty) = splitAppTy (exprType expr2) -- Must be of form (m a) + fail_expr = HsApp (TyApp (HsVar fail_id) [b_ty]) + (HsLitOut (HsString (_PK_ msg)) stringTy) + msg = ASSERT2( isNotUsgTy a_ty, ppr a_ty ) + ASSERT2( isNotUsgTy b_ty, ppr b_ty ) + "Pattern match failure in do expression, " ++ showSDoc (ppr locn) main_match = mkSimpleMatch [pat] - (HsDoOut do_or_lc stmts return_id then_id fail_id result_ty locn) + (HsDoOut do_or_lc stmts return_id then_id + fail_id result_ty locn) (Just result_ty) locn the_matches | failureFreePat pat = [main_match] @@ -673,3 +660,13 @@ var_pat (VarPat _) = True var_pat _ = False \end{code} +\begin{code} +mkIntegerLit :: Integer -> CoreExpr +mkIntegerLit i + | inIntRange i -- Small enough, so start from an Int + = mkConApp smallIntegerDataCon [mkIntLit i] + + | otherwise -- Big, so start from a string + = App (Var addr2IntegerId) (Lit (MachStr (_PK_ (show i)))) +\end{code} +