X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FdeSugar%2FDsForeign.lhs;h=52956a09fff45264bc2f6f7b9782e0f339f0e290;hb=28a464a75e14cece5db40f2765a29348273ff2d2;hp=84ccaf4f8ae2633f380a259db627a0cdb37a1826;hpb=0926a3ca0b5caabc00b8dad7912495a25f63d099;p=ghc-hetmet.git diff --git a/ghc/compiler/deSugar/DsForeign.lhs b/ghc/compiler/deSugar/DsForeign.lhs index 84ccaf4..52956a0 100644 --- a/ghc/compiler/deSugar/DsForeign.lhs +++ b/ghc/compiler/deSugar/DsForeign.lhs @@ -9,331 +9,337 @@ Expanding out @foreign import@ and @foreign export@ declarations. module DsForeign ( dsForeigns ) where #include "HsVersions.h" +import TcRnMonad -- temp import CoreSyn -import DsCCall ( dsCCall, boxResult, unboxArg, wrapUnboxedValue ) +import DsCCall ( dsCCall, mkFCall, boxResult, unboxArg, resultWrapper ) import DsMonad -import DsUtils - -import HsSyn ( ExtName(..), ForeignDecl(..), isDynamic, ForKind(..) ) -import CallConv -import TcHsSyn ( TypecheckedForeignDecl ) -import CoreUtils ( coreExprType ) -import Const ( Con(..), mkMachInt ) -import DataCon ( DataCon, dataConId ) -import Id ( Id, idType, idName, - mkIdVisible, mkWildId - ) -import Const ( Literal(..) ) + +import HsSyn ( ForeignDecl(..), ForeignExport(..), LForeignDecl, + ForeignImport(..), CImportSpec(..) ) +import DataCon ( splitProductType_maybe ) +#ifdef DEBUG +import DataCon ( dataConSourceArity ) +import Type ( isUnLiftedType ) +#endif +import MachOp ( machRepByteWidth, MachRep(..) ) +import SMRep ( argMachRep, typeCgRep ) +import CoreUtils ( exprType, mkInlineMe ) +import Id ( Id, idType, idName, mkSysLocal, setInlinePragma ) +import Literal ( Literal(..), mkStringLit ) +import Module ( moduleFS ) import Name ( getOccString, NamedThing(..) ) -import PrelVals ( realWorldPrimId ) -import PrelInfo ( deRefStablePtr_NAME, bindIO_NAME, makeStablePtr_NAME ) -import Type ( splitAlgTyConApp_maybe, - splitTyConApp_maybe, splitFunTys, splitForAllTys, - Type, mkFunTys, mkForAllTys, mkTyConApp, - mkTyVarTy, mkFunTy, splitAppTy +import Type ( repType, coreEqType ) +import TcType ( Type, mkFunTys, mkForAllTys, mkTyConApp, + mkFunTy, tcSplitTyConApp_maybe, + tcSplitForAllTys, tcSplitFunTys, tcTyConAppArgs, ) -import PrimOp ( PrimOp(..) ) -import Var ( TyVar ) -import TysPrim ( realWorldStatePrimTy, addrPrimTy ) -import TysWiredIn ( unitTyCon, addrTy, stablePtrTyCon, - unboxedTupleCon, addrDataCon + +import BasicTypes ( Boxity(..) ) +import HscTypes ( ForeignStubs(..) ) +import ForeignCall ( ForeignCall(..), CCallSpec(..), + Safety(..), playSafe, + CExportSpec(..), CLabelString, + CCallConv(..), ccallConvToInt, + ccallConvAttribute ) -import Unique +import TysWiredIn ( unitTy, tupleTyCon ) +import TysPrim ( addrPrimTy, mkStablePtrPrimTy, alphaTy ) +import PrelNames ( hasKey, ioTyConKey, stablePtrTyConName, newStablePtrName, bindIOName, + checkDotnetResName ) +import BasicTypes ( Activation( NeverActive ) ) +import SrcLoc ( Located(..), unLoc ) import Outputable +import Maybe ( fromJust, isNothing ) +import FastString \end{code} Desugaring of @foreign@ declarations is naturally split up into parts, an @import@ and an @export@ part. A @foreign import@ -declaration - +declaration +\begin{verbatim} foreign import cc nm f :: prim_args -> IO prim_res - +\end{verbatim} is the same as - +\begin{verbatim} f :: prim_args -> IO prim_res f a1 ... an = _ccall_ nm cc a1 ... an - +\end{verbatim} so we reuse the desugaring code in @DsCCall@ to deal with these. \begin{code} -dsForeigns :: [TypecheckedForeignDecl] - -> DsM ( [CoreBind] -- desugared foreign imports - , [CoreBind] -- helper functions for foreign exports - , SDoc -- Header file prototypes for "foreign exported" functions. - , SDoc -- C stubs to use when calling "foreign exported" funs. - ) -dsForeigns fos = foldlDs combine ([],[],empty,empty) fos +type Binding = (Id, CoreExpr) -- No rec/nonrec structure; + -- the occurrence analyser will sort it all out + +dsForeigns :: [LForeignDecl Id] + -> DsM (ForeignStubs, [Binding]) +dsForeigns [] + = returnDs (NoStubs, []) +dsForeigns fos + = foldlDs combine (ForeignStubs empty empty [] [], []) fos where - combine (acc_fi, acc_fe, acc_h, acc_c) fo@(ForeignDecl i imp_exp _ ext_nm cconv _) - | isForeignImport = -- foreign import (dynamic)? - dsFImport i (idType i) uns ext_nm cconv `thenDs` \ b -> - returnDs (b:acc_fi, acc_fe, acc_h, acc_c) - | isForeignLabel = - dsFLabel i ext_nm `thenDs` \ b -> - returnDs (b:acc_fi, acc_fe, acc_h, acc_c) - | isDynamic ext_nm = - dsFExportDynamic i (idType i) ext_nm cconv `thenDs` \ (fi,fe,h,c) -> - returnDs (fi:acc_fi, fe:acc_fe, h $$ acc_h, c $$ acc_c) - - | otherwise = -- foreign export - dsFExport i (idType i) ext_nm cconv False `thenDs` \ (fe,h,c) -> - returnDs (acc_fi, fe:acc_fe, h $$ acc_h, c $$ acc_c) - where - isForeignImport = - case imp_exp of - FoImport _ -> True - _ -> False - - isForeignLabel = - case imp_exp of - FoLabel -> True - _ -> False - - (FoImport uns) = imp_exp - + combine stubs (L loc decl) = putSrcSpanDs loc (combine1 stubs decl) + + combine1 (ForeignStubs acc_h acc_c acc_hdrs acc_feb, acc_f) + (ForeignImport id _ spec depr) + = traceIf (text "fi start" <+> ppr id) `thenDs` \ _ -> + dsFImport (unLoc id) spec `thenDs` \ (bs, h, c, mbhd) -> + warnDepr depr `thenDs` \ _ -> + traceIf (text "fi end" <+> ppr id) `thenDs` \ _ -> + returnDs (ForeignStubs (h $$ acc_h) + (c $$ acc_c) + (addH mbhd acc_hdrs) + acc_feb, + bs ++ acc_f) + + combine1 (ForeignStubs acc_h acc_c acc_hdrs acc_feb, acc_f) + (ForeignExport (L _ id) _ (CExport (CExportStatic ext_nm cconv)) depr) + = dsFExport id (idType id) + ext_nm cconv False `thenDs` \(h, c, _, _) -> + warnDepr depr `thenDs` \_ -> + returnDs (ForeignStubs (h $$ acc_h) (c $$ acc_c) acc_hdrs (id:acc_feb), + acc_f) + + addH Nothing ls = ls + addH (Just e) ls + | e `elem` ls = ls + | otherwise = e:ls + + warnDepr False = returnDs () + warnDepr True = dsWarn msg + where + msg = ptext SLIT("foreign declaration uses deprecated non-standard syntax") \end{code} + +%************************************************************************ +%* * +\subsection{Foreign import} +%* * +%************************************************************************ + Desugaring foreign imports is just the matter of creating a binding that on its RHS unboxes its arguments, performs the external call -(using the CCallOp primop), before boxing the result up and returning it. +(using the @CCallOp@ primop), before boxing the result up and returning it. -\begin{code} -dsFImport :: Id - -> Type -- Type of foreign import. - -> Bool -- True <=> might cause Haskell GC - -> ExtName - -> CallConv - -> DsM CoreBind -dsFImport nm ty may_not_gc ext_name cconv = - newSysLocalDs realWorldStatePrimTy `thenDs` \ old_s -> - splitForeignTyDs ty `thenDs` \ (tvs, args, mbIoDataCon, io_res_ty) -> - let - the_state_arg - | is_io_action = old_s - | otherwise = realWorldPrimId +However, we create a worker/wrapper pair, thus: - arg_exprs = map (Var) args + foreign import f :: Int -> IO Int +==> + f x = IO ( \s -> case x of { I# x# -> + case fw s x# of { (# s1, y# #) -> + (# s1, I# y# #)}}) - is_io_action = - case mbIoDataCon of - Nothing -> False - _ -> True - in - mapAndUnzipDs unboxArg arg_exprs `thenDs` \ (unboxed_args, arg_wrappers) -> - (if not is_io_action then - newSysLocalDs realWorldStatePrimTy `thenDs` \ state_tok -> - wrapUnboxedValue io_res_ty `thenDs` \ (ccall_result_ty, v, res_v) -> - returnDs ( ccall_result_ty - , \ prim_app -> Case prim_app (mkWildId ccall_result_ty) - [(DataCon (unboxedTupleCon 2), [state_tok, v], res_v)]) - else - boxResult io_res_ty) `thenDs` \ (final_result_ty, res_wrapper) -> - (case ext_name of - Dynamic -> getUniqueDs `thenDs` \ u -> - returnDs (Right u) - ExtName fs _ -> returnDs (Left fs)) `thenDs` \ label -> - let - val_args = Var the_state_arg : unboxed_args - final_args = Type inst_ty : val_args + fw s x# = ccall f s x# - -- A CCallOp has type (forall a. a), so we must instantiate - -- it at the full type, including the state argument - inst_ty = mkFunTys (map coreExprType val_args) final_result_ty +The strictness/CPR analyser won't do this automatically because it doesn't look +inside returned tuples; but inlining this wrapper is a Really Good Idea +because it exposes the boxing to the call site. - the_ccall_op = CCallOp label False (not may_not_gc) cconv +\begin{code} +dsFImport :: Id + -> ForeignImport + -> DsM ([Binding], SDoc, SDoc, Maybe FastString) +dsFImport id (CImport cconv safety header lib spec) + = dsCImport id spec cconv safety no_hdrs `thenDs` \(ids, h, c) -> + returnDs (ids, h, c, if no_hdrs then Nothing else Just header) + where + no_hdrs = nullFS header + + -- FIXME: the `lib' field is needed for .NET ILX generation when invoking + -- routines that are external to the .NET runtime, but GHC doesn't + -- support such calls yet; if `nullFastString lib', the value was not given +dsFImport id (DNImport spec) + = dsFCall id (DNCall spec) True {- No headers -} `thenDs` \(ids, h, c) -> + returnDs (ids, h, c, Nothing) + +dsCImport :: Id + -> CImportSpec + -> CCallConv + -> Safety + -> Bool -- True <=> no headers in the f.i decl + -> DsM ([Binding], SDoc, SDoc) +dsCImport id (CLabel cid) _ _ no_hdrs + = resultWrapper (idType id) `thenDs` \ (resTy, foRhs) -> + ASSERT(fromJust resTy `coreEqType` addrPrimTy) -- typechecker ensures this + let rhs = foRhs (mkLit (MachLabel cid Nothing)) in + returnDs ([(setImpInline no_hdrs id, rhs)], empty, empty) +dsCImport id (CFunction target) cconv safety no_hdrs + = dsFCall id (CCall (CCallSpec target cconv safety)) no_hdrs +dsCImport id CWrapper cconv _ _ + = dsFExportDynamic id cconv + +setImpInline :: Bool -- True <=> No #include headers + -- in the foreign import declaration + -> Id -> Id +-- If there is a #include header in the foreign import +-- we make the worker non-inlinable, because we currently +-- don't keep the #include stuff in the CCallId, and hence +-- it won't be visible in the importing module, which can be +-- fatal. +-- (The #include stuff is just collected from the foreign import +-- decls in a module.) +-- If you want to do cross-module inlining of the c-calls themselves, +-- put the #include stuff in the package spec, not the foreign +-- import decl. +setImpInline True id = id +setImpInline False id = id `setInlinePragma` NeverActive +\end{code} - the_prim_app = mkPrimApp the_ccall_op (final_args :: [CoreArg]) - body = foldr ($) (res_wrapper the_prim_app) arg_wrappers +%************************************************************************ +%* * +\subsection{Foreign calls} +%* * +%************************************************************************ - the_body - | not is_io_action = body - | otherwise = Lam old_s body +\begin{code} +dsFCall fn_id fcall no_hdrs + = let + ty = idType fn_id + (tvs, fun_ty) = tcSplitForAllTys ty + (arg_tys, io_res_ty) = tcSplitFunTys fun_ty + -- Must use tcSplit* functions because we want to + -- see that (IO t) in the corner in - newSysLocalDs (coreExprType the_body) `thenDs` \ ds -> + newSysLocalsDs arg_tys `thenDs` \ args -> + mapAndUnzipDs unboxArg (map Var args) `thenDs` \ (val_args, arg_wrappers) -> + let - io_app = - case mbIoDataCon of - Nothing -> Var ds - Just ioDataCon -> - mkApps (Var (dataConId ioDataCon)) - [Type io_res_ty, Var ds] - - fo_rhs = mkLams (tvs ++ args) - (Let (NonRec ds (the_body::CoreExpr)) io_app) + work_arg_ids = [v | Var v <- val_args] -- All guaranteed to be vars + + forDotnet = + case fcall of + DNCall{} -> True + _ -> False + + topConDs + | forDotnet = + dsLookupGlobalId checkDotnetResName `thenDs` \ check_id -> + return (Just check_id) + | otherwise = return Nothing + + augmentResultDs + | forDotnet = + newSysLocalDs addrPrimTy `thenDs` \ err_res -> + returnDs (\ (mb_res_ty, resWrap) -> + case mb_res_ty of + Nothing -> (Just (mkTyConApp (tupleTyCon Unboxed 1) + [ addrPrimTy ]), + resWrap) + Just x -> (Just (mkTyConApp (tupleTyCon Unboxed 2) + [ x, addrPrimTy ]), + resWrap)) + | otherwise = returnDs id in - returnDs (NonRec nm fo_rhs) -\end{code} + augmentResultDs `thenDs` \ augment -> + topConDs `thenDs` \ topCon -> + boxResult augment topCon io_res_ty `thenDs` \ (ccall_result_ty, res_wrapper) -> -Given the type of a foreign import declaration, split it up into -its constituent parts. - -\begin{code} -splitForeignTyDs :: Type -> DsM ([TyVar], [Id], Maybe DataCon, Type) -splitForeignTyDs ty = - newSysLocalsDs arg_tys `thenDs` \ ds_args -> - case splitAlgTyConApp_maybe res_ty of - Just (_,(io_res_ty:_),(ioCon:_)) -> -- .... -> IO t - returnDs (tvs, ds_args, Just ioCon, io_res_ty) - _ -> -- .... -> t - returnDs (tvs, ds_args, Nothing, res_ty) - where - (arg_tys, res_ty) = splitFunTys sans_foralls - (tvs, sans_foralls) = splitForAllTys ty + newUnique `thenDs` \ ccall_uniq -> + newUnique `thenDs` \ work_uniq -> + let + -- Build the worker + worker_ty = mkForAllTys tvs (mkFunTys (map idType work_arg_ids) ccall_result_ty) + the_ccall_app = mkFCall ccall_uniq fcall val_args ccall_result_ty + work_rhs = mkLams tvs (mkLams work_arg_ids the_ccall_app) + work_id = setImpInline no_hdrs $ -- See comments with setImpInline + mkSysLocal FSLIT("$wccall") work_uniq worker_ty + + -- Build the wrapper + work_app = mkApps (mkVarApps (Var work_id) tvs) val_args + wrapper_body = foldr ($) (res_wrapper work_app) arg_wrappers + wrap_rhs = mkInlineMe (mkLams (tvs ++ args) wrapper_body) + in + returnDs ([(work_id, work_rhs), (fn_id, wrap_rhs)], empty, empty) +unsafe_call (CCall (CCallSpec _ _ safety)) = playSafe safety +unsafe_call (DNCall _) = False \end{code} -foreign labels -\begin{code} -dsFLabel :: Id -> ExtName -> DsM CoreBind -dsFLabel nm ext_name = returnDs (NonRec nm fo_rhs) - where - fo_rhs = mkConApp addrDataCon [mkLit (MachLitLit enm addrPrimTy)] - enm = - case ext_name of - ExtName f _ -> f - Dynamic -> panic "dsFLabel: Dynamic - shouldn't ever happen." +%************************************************************************ +%* * +\subsection{Foreign export} +%* * +%************************************************************************ -\end{code} - -The function that does most of the work for 'foreign export' declarations. -(see below for the boilerplate code a 'foreign export' declaration expands +The function that does most of the work for `@foreign export@' declarations. +(see below for the boilerplate code a `@foreign export@' declaration expands into.) +For each `@foreign export foo@' in a module M we generate: +\begin{itemize} +\item a C function `@foo@', which calls +\item a Haskell stub `@M.$ffoo@', which calls +\end{itemize} +the user-written Haskell function `@M.foo@'. + \begin{code} -dsFExport :: Id - -> Type -- Type of foreign export. - -> ExtName - -> CallConv - -> Bool -- True => invoke IO action that's hanging off - -- the first argument's stable pointer - -> DsM ( CoreBind - , SDoc - , SDoc +dsFExport :: Id -- Either the exported Id, + -- or the foreign-export-dynamic constructor + -> Type -- The type of the thing callable from C + -> CLabelString -- The name to export to C land + -> CCallConv + -> Bool -- True => foreign export dynamic + -- so invoke IO action that's hanging off + -- the first argument's stable pointer + -> DsM ( SDoc -- contents of Module_stub.h + , SDoc -- contents of Module_stub.c + , [MachRep] -- primitive arguments expected by stub function + , Int -- size of args to stub function ) -dsFExport i ty ext_name cconv isDyn = - newSysLocalDs helper_ty `thenDs` \ f_helper -> - newSysLocalsDs fe_arg_tys `thenDs` \ fe_args -> - (if isDyn then - newSysLocalDs stbl_ptr_ty `thenDs` \ stbl_ptr -> - newSysLocalDs stbl_ptr_to_ty `thenDs` \ stbl_value -> - dsLookupGlobalValue deRefStablePtr_NAME `thenDs` \ deRefStablePtrId -> - let - the_deref_app = mkApps (Var deRefStablePtrId) - [ Type stbl_ptr_to_ty, Var stbl_ptr ] - in - newSysLocalDs (coreExprType the_deref_app) `thenDs` \ x_deref_app -> - dsLookupGlobalValue bindIO_NAME `thenDs` \ bindIOId -> - newSysLocalDs (mkFunTy stbl_ptr_to_ty - (mkTyConApp ioTyCon [res_ty])) `thenDs` \ x_cont -> - let - stbl_app = \ cont -> - bindNonRec x_cont (mkLams [stbl_value] cont) $ - bindNonRec x_deref_app the_deref_app - (mkApps (Var bindIOId) - [ Type stbl_ptr_to_ty - , Type res_ty - , Var x_deref_app - , Var x_cont]) - in - returnDs (stbl_value, stbl_app, stbl_ptr) - else - returnDs (i, - \ body -> body, - panic "stbl_ptr" -- should never be touched. - )) `thenDs` \ (i, getFun_wrapper, stbl_ptr) -> - let - wrapper_args - | isDyn = stbl_ptr:fe_args - | otherwise = fe_args - wrapper_arg_tys - | isDyn = stbl_ptr_ty:helper_arg_tys - | otherwise = helper_arg_tys - - the_app = - getFun_wrapper $ - mkApps (Var i) (map (Type . mkTyVarTy) tvs ++ map Var fe_args) - in - getModuleAndGroupDs `thenDs` \ (mod,_) -> - getUniqueDs `thenDs` \ uniq -> +dsFExport fn_id ty ext_name cconv isDyn + = let - the_body = mkLams (tvs ++ wrapper_args) the_app - - c_nm = - case ext_name of - ExtName fs _ -> fs - Dynamic -> panic "dsFExport: Dynamic - shouldn't ever happen." - - f_helper_glob = mkIdVisible mod uniq f_helper - (h_stub, c_stub) = fexportEntry c_nm f_helper_glob wrapper_arg_tys the_result_ty cconv isDyn + (_tvs,sans_foralls) = tcSplitForAllTys ty + (fe_arg_tys', orig_res_ty) = tcSplitFunTys sans_foralls + -- We must use tcSplits here, because we want to see + -- the (IO t) in the corner of the type! + fe_arg_tys | isDyn = tail fe_arg_tys' + | otherwise = fe_arg_tys' in - returnDs (NonRec f_helper_glob the_body, h_stub, c_stub) - - where - - (tvs,sans_foralls) = splitForAllTys ty - (fe_arg_tys', io_res) = splitFunTys sans_foralls - - - Just (ioTyCon, [res_ty]) = splitTyConApp_maybe io_res - - (_, stbl_ptr_ty') = splitForAllTys stbl_ptr_ty - (_, stbl_ptr_to_ty) = splitAppTy stbl_ptr_ty' - - fe_arg_tys - | isDyn = tail fe_arg_tys' - | otherwise = fe_arg_tys' - - (stbl_ptr_ty, helper_arg_tys) = - case fe_arg_tys' of - (x:xs) | isDyn -> (x,xs) - ls -> (error "stbl_ptr_ty", ls) - - helper_ty = - mkForAllTys tvs $ - mkFunTys arg_tys io_res - where - arg_tys - | isDyn = stbl_ptr_ty : helper_arg_tys - | otherwise = helper_arg_tys - - the_result_ty = - case splitTyConApp_maybe io_res of - Just (_,[res_ty]) -> - case splitTyConApp_maybe res_ty of - Just (tc,_) | getUnique tc /= getUnique unitTyCon -> Just res_ty - _ -> Nothing - _ -> Nothing - + -- Look at the result type of the exported function, orig_res_ty + -- If it's IO t, return (t, True) + -- If it's plain t, return (t, False) + (case tcSplitTyConApp_maybe orig_res_ty of + -- We must use tcSplit here so that we see the (IO t) in + -- the type. [IO t is transparent to plain splitTyConApp.] + + Just (ioTyCon, [res_ty]) + -> ASSERT( ioTyCon `hasKey` ioTyConKey ) + -- The function already returns IO t + returnDs (res_ty, True) + + other -> -- The function returns t + returnDs (orig_res_ty, False) + ) + `thenDs` \ (res_ty, -- t + is_IO_res_ty) -> -- Bool + returnDs $ + mkFExportCBits ext_name + (if isDyn then Nothing else Just fn_id) + fe_arg_tys res_ty is_IO_res_ty cconv \end{code} -"foreign export dynamic" lets you dress up Haskell IO actions +@foreign export dynamic@ lets you dress up Haskell IO actions of some fixed type behind an externally callable interface (i.e., as a C function pointer). Useful for callbacks and stuff. \begin{verbatim} -foreign export stdcall f :: (Addr -> Int -> IO Int) -> IO Addr +foreign export dynamic f :: (Addr -> Int -> IO Int) -> IO Addr --- Haskell-visible constructor, which is generated from the --- above: +-- Haskell-visible constructor, which is generated from the above: +-- SUP: No check for NULL from createAdjustor anymore??? f :: (Addr -> Int -> IO Int) -> IO Addr -f cback = IO ( \ s1# -> - case makeStablePtr# cback s1# of { StateAndStablePtr# s2# sp# -> - case _ccall_ "mkAdjustor" sp# ``f_helper'' s2# of - StateAndAddr# s3# a# -> - case addr2Int# a# of - 0# -> IOfail s# err - _ -> - let - a :: Addr - a = A# a# - in - IOok s3# a) +f cback = + bindIO (newStablePtr cback) + (\StablePtr sp# -> IO (\s1# -> + case _ccall_ createAdjustor cconv sp# ``f_helper'' s1# of + (# s2#, a# #) -> (# s2#, A# a# #))) foreign export "f_helper" f_helper :: StablePtr (Addr -> Int -> IO Int) -> Addr -> Int -> IO Int -- `special' foreign export that invokes the closure pointed to by the @@ -342,38 +348,34 @@ foreign export "f_helper" f_helper :: StablePtr (Addr -> Int -> IO Int) -> Addr \begin{code} dsFExportDynamic :: Id - -> Type -- Type of foreign export. - -> ExtName - -> CallConv - -> DsM (CoreBind, CoreBind, SDoc, SDoc) -dsFExportDynamic i ty ext_name cconv = - newSysLocalDs ty `thenDs` \ fe_id -> + -> CCallConv + -> DsM ([Binding], SDoc, SDoc) +dsFExportDynamic id cconv + = newSysLocalDs ty `thenDs` \ fe_id -> + getModuleDs `thenDs` \ mod_name -> let -- hack: need to get at the name of the C stub we're about to generate. - fe_nm = toCName fe_id - fe_ext_name = ExtName (_PK_ fe_nm) Nothing + fe_nm = mkFastString (unpackFS (zEncodeFS (moduleFS mod_name)) ++ "_" ++ toCName fe_id) in - dsFExport i export_ty fe_ext_name cconv True `thenDs` \ (fe@(NonRec fe_helper fe_expr), h_code, c_code) -> - newSysLocalDs arg_ty `thenDs` \ cback -> - dsLookupGlobalValue makeStablePtr_NAME `thenDs` \ makeStablePtrId -> + newSysLocalDs arg_ty `thenDs` \ cback -> + dsLookupGlobalId newStablePtrName `thenDs` \ newStablePtrId -> + dsLookupTyCon stablePtrTyConName `thenDs` \ stable_ptr_tycon -> let - mk_stbl_ptr_app = mkApps (Var makeStablePtrId) [ Type arg_ty, Var cback ] - mk_stbl_ptr_app_ty = coreExprType mk_stbl_ptr_app + mk_stbl_ptr_app = mkApps (Var newStablePtrId) [ Type arg_ty, Var cback ] + stable_ptr_ty = mkTyConApp stable_ptr_tycon [arg_ty] + export_ty = mkFunTy stable_ptr_ty arg_ty in - newSysLocalDs mk_stbl_ptr_app_ty `thenDs` \ x_mk_stbl_ptr_app -> - dsLookupGlobalValue bindIO_NAME `thenDs` \ bindIOId -> - newSysLocalDs (mkTyConApp stablePtrTyCon [arg_ty]) `thenDs` \ stbl_value -> + dsLookupGlobalId bindIOName `thenDs` \ bindIOId -> + newSysLocalDs stable_ptr_ty `thenDs` \ stbl_value -> + dsFExport id export_ty fe_nm cconv True + `thenDs` \ (h_code, c_code, arg_reps, args_size) -> let - stbl_app = \ x_cont cont ret_ty -> - bindNonRec x_cont cont $ - bindNonRec x_mk_stbl_ptr_app mk_stbl_ptr_app $ - (mkApps (Var bindIOId) - [ Type (mkTyConApp stablePtrTyCon [arg_ty]) - , Type ret_ty - , Var x_mk_stbl_ptr_app - , Var x_cont - ]) - + stbl_app cont ret_ty = mkApps (Var bindIOId) + [ Type stable_ptr_ty + , Type ret_ty + , mk_stbl_ptr_app + , cont + ] {- The arguments to the external function which will create a little bit of (template) code on the fly @@ -381,42 +383,53 @@ dsFExportDynamic i ty ext_name cconv = to be entered using an external calling convention (stdcall, ccall). -} - adj_args = [ mkLit (mkMachInt (fromInt (callConvToInt cconv))) + adj_args = [ mkIntLitInt (ccallConvToInt cconv) , Var stbl_value - , mkLit (MachLitLit (_PK_ fe_nm) addrPrimTy) + , mkLit (MachLabel fe_nm mb_sz_args) + , mkLit (mkStringLit arg_type_info) ] -- name of external entry point providing these services. -- (probably in the RTS.) - adjustor = SLIT("createAdjustor") - in - dsCCall adjustor adj_args False False addrTy `thenDs` \ ccall_adj -> - let ccall_adj_ty = coreExprType ccall_adj - in - newSysLocalDs ccall_adj_ty `thenDs` \ x_ccall_adj -> - let ccall_io_adj = - mkLams [stbl_value] $ - bindNonRec x_ccall_adj ccall_adj $ - Note (Coerce (mkTyConApp ioTyCon [res_ty]) ccall_adj_ty) - (Var x_ccall_adj) + adjustor = FSLIT("createAdjustor") + + arg_type_info = map repCharCode arg_reps + repCharCode F32 = 'f' + repCharCode F64 = 'd' + repCharCode I64 = 'l' + repCharCode _ = 'i' + + -- Determine the number of bytes of arguments to the stub function, + -- so that we can attach the '@N' suffix to its label if it is a + -- stdcall on Windows. + mb_sz_args = case cconv of + StdCallConv -> Just args_size + _ -> Nothing + in - newSysLocalDs (coreExprType ccall_io_adj) `thenDs` \ x_ccall_io_adj -> - let io_app = mkLams tvs $ + dsCCall adjustor adj_args PlayRisky io_res_ty `thenDs` \ ccall_adj -> + -- PlayRisky: the adjustor doesn't allocate in the Haskell heap or do a callback + let ccall_adj_ty = exprType ccall_adj + ccall_io_adj = mkLams [stbl_value] $ + Note (Coerce io_res_ty ccall_adj_ty) + ccall_adj + io_app = mkLams tvs $ mkLams [cback] $ - stbl_app x_ccall_io_adj ccall_io_adj addrTy + stbl_app ccall_io_adj res_ty + fed = (id `setInlinePragma` NeverActive, io_app) + -- Never inline the f.e.d. function, because the litlit + -- might not be in scope in other modules. in - returnDs (NonRec i io_app, fe, h_code, c_code) + returnDs ([fed], h_code, c_code) where - (tvs,sans_foralls) = splitForAllTys ty - ([arg_ty], io_res) = splitFunTys sans_foralls - - Just (ioTyCon, [res_ty]) = splitTyConApp_maybe io_res - - export_ty = mkFunTy (mkTyConApp stablePtrTyCon [arg_ty]) arg_ty + ty = idType id + (tvs,sans_foralls) = tcSplitForAllTys ty + ([arg_ty], io_res_ty) = tcSplitFunTys sans_foralls + [res_ty] = tcTyConAppArgs io_res_ty + -- Must use tcSplit* to see the (IO t), which is a newtype toCName :: Id -> String toCName i = showSDoc (pprCode CStyle (ppr (idName i))) - \end{code} %* @@ -430,98 +443,204 @@ The C stub constructs the application of the exported Haskell function using the hugs/ghc rts invocation API. \begin{code} -fexportEntry :: FAST_STRING - -> Id - -> [Type] - -> Maybe Type - -> CallConv - -> Bool - -> (SDoc, SDoc) -fexportEntry c_nm helper args res cc isDyn = (header_bits, c_bits) +mkFExportCBits :: FastString + -> Maybe Id -- Just==static, Nothing==dynamic + -> [Type] + -> Type + -> Bool -- True <=> returns an IO type + -> CCallConv + -> (SDoc, + SDoc, + [MachRep], -- the argument reps + Int -- total size of arguments + ) +mkFExportCBits c_nm maybe_target arg_htys res_hty is_IO_res_ty cc + = (header_bits, c_bits, + [rep | (_,_,_,rep) <- arg_info], -- just the real args + sum [ machRepByteWidth rep | (_,_,_,rep) <- aug_arg_info] -- all the args + ) where - -- name of the (Haskell) helper function generated by the desugarer. - h_nm = ppr helper <> text "_closure" - -- prototype for the exported function. + -- list the arguments to the C function + arg_info :: [(SDoc, -- arg name + SDoc, -- C type + Type, -- Haskell type + MachRep)] -- the MachRep + arg_info = [ (text ('a':show n), showStgType ty, ty, + typeMachRep (getPrimTyOf ty)) + | (ty,n) <- zip arg_htys [1..] ] + + -- add some auxiliary args; the stable ptr in the wrapper case, and + -- a slot for the dummy return address in the wrapper + ccall case + aug_arg_info + | isNothing maybe_target = stable_ptr_arg : insertRetAddr cc arg_info + | otherwise = arg_info + + stable_ptr_arg = + (text "the_stableptr", text "StgStablePtr", undefined, + typeMachRep (mkStablePtrPrimTy alphaTy)) + + -- stuff to do with the return type of the C function + res_hty_is_unit = res_hty `coreEqType` unitTy -- Look through any newtypes + + cResType | res_hty_is_unit = text "void" + | otherwise = showStgType res_hty + + -- Now we can cook up the prototype for the exported function. + pprCconv = case cc of + CCallConv -> empty + StdCallConv -> text (ccallConvAttribute cc) + header_bits = ptext SLIT("extern") <+> fun_proto <> semi - fun_proto = cResType <+> pprCconv <+> ptext c_nm <> - parens (hsep (punctuate comma (zipWith (<+>) cParamTypes proto_args))) + fun_proto = cResType <+> pprCconv <+> ftext c_nm <> + parens (hsep (punctuate comma (map (\(nm,ty,_,_) -> ty <+> nm) + aug_arg_info))) + + -- the target which will form the root of what we ask rts_evalIO to run + the_cfun + = case maybe_target of + Nothing -> text "(StgClosure*)deRefStablePtr(the_stableptr)" + Just hs_fn -> char '&' <> ppr hs_fn <> text "_closure" + + cap = text "cap" <> comma + + -- the expression we give to rts_evalIO + expr_to_run + = foldl appArg the_cfun arg_info -- NOT aug_arg_info + where + appArg acc (arg_cname, _, arg_hty, _) + = text "rts_apply" + <> parens (cap <> acc <> comma <> mkHObj arg_hty <> parens (cap <> arg_cname)) + + -- various other bits for inside the fn + declareResult = text "HaskellObj ret;" + declareCResult | res_hty_is_unit = empty + | otherwise = cResType <+> text "cret;" + + assignCResult | res_hty_is_unit = empty + | otherwise = + text "cret=" <> unpackHObj res_hty <> parens (text "ret") <> semi + + -- an extern decl for the fn being called + extern_decl + = case maybe_target of + Nothing -> empty + Just hs_fn -> text "extern StgClosure " <> ppr hs_fn <> text "_closure" <> semi + + -- Initialise foreign exports by registering a stable pointer from an + -- __attribute__((constructor)) function. + -- The alternative is to do this from stginit functions generated in + -- codeGen/CodeGen.lhs; however, stginit functions have a negative impact + -- on binary sizes and link times because the static linker will think that + -- all modules that are imported directly or indirectly are actually used by + -- the program. + -- (this is bad for big umbrella modules like Graphics.Rendering.OpenGL) + + initialiser + = case maybe_target of + Nothing -> empty + Just hs_fn -> + vcat + [ text "static void stginit_export_" <> ppr hs_fn + <> text "() __attribute__((constructor));" + , text "static void stginit_export_" <> ppr hs_fn <> text "()" + , braces (text "getStablePtr" + <> parens (text "(StgPtr) &" <> ppr hs_fn <> text "_closure") + <> semi) + ] + + -- finally, the whole darn thing c_bits = - externDecl $$ + space $$ + extern_decl $$ fun_proto $$ vcat [ lbrace - , text "SchedulerStatus rc;" + , text "Capability *cap;" , declareResult + , declareCResult + , text "cap = rts_lock();" -- create the application + perform it. - , text "rc=rts_evalIO" <> - parens (foldl appArg (text "(StgClosure*)&" <> h_nm) (zip args c_args) <> comma <> text "&ret") <> semi - , returnResult + , text "cap=rts_evalIO" <> parens ( + cap <> + text "rts_apply" <> parens ( + cap <> + text "(HaskellObj)" + <> text (if is_IO_res_ty + then "runIO_closure" + else "runNonIO_closure") + <> comma + <> expr_to_run + ) <+> comma + <> text "&ret" + ) <> semi + , text "rts_checkSchedStatus" <> parens (doubleQuotes (ftext c_nm) + <> comma <> text "cap") <> semi + , assignCResult + , text "rts_unlock(cap);" + , if res_hty_is_unit then empty + else text "return cret;" , rbrace - ] - - appArg acc (a,c_a) = - text "rts_apply" <> parens (acc <> comma <> mkHObj a <> parens c_a) - - cParamTypes = map showStgType real_args - - cResType = - case res of - Nothing -> text "void" - Just t -> showStgType t - - pprCconv - | cc == cCallConv = empty - | otherwise = pprCallConv cc - - declareResult = text "HaskellObj ret;" - - externDecl = mkExtern (text "HaskellObj") h_nm - - mkExtern ty nm = text "extern" <+> ty <+> nm <> semi - - returnResult = - text "rts_checkSchedStatus" <> - parens (doubleQuotes (ptext c_nm) <> comma <> text "rc") <> semi $$ - (case res of - Nothing -> text "return" - Just _ -> text "return" <> parens (res_name)) <> semi - - res_name = - case res of - Nothing -> empty - Just t -> unpackHObj t <> parens (text "ret") - - c_args = mkCArgNames 0 args - - {- - If we're generating an entry point for a 'foreign export ccall dynamic', - then we receive the return address of the C function that wants to - invoke a Haskell function as any other C function, as second arg. - This arg is unused within the body of the generated C stub, but - needed by the Adjustor.c code to get the stack cleanup right. - -} - (proto_args, real_args) - | cc == cCallConv && isDyn = ( text "a0" : text "a_" : mkCArgNames 1 (tail args) - , head args : addrTy : tail args) - | otherwise = (mkCArgNames 0 args, args) - - mkCArgNames n as = zipWith (\ _ n -> text ('a':show n)) as [n..] + ] $$ + initialiser + +-- NB. the calculation here isn't strictly speaking correct. +-- We have a primitive Haskell type (eg. Int#, Double#), and +-- we want to know the size, when passed on the C stack, of +-- the associated C type (eg. HsInt, HsDouble). We don't have +-- this information to hand, but we know what GHC's conventions +-- are for passing around the primitive Haskell types, so we +-- use that instead. I hope the two coincide --SDM +typeMachRep ty = argMachRep (typeCgRep ty) mkHObj :: Type -> SDoc -mkHObj t = text "rts_mk" <> showFFIType t +mkHObj t = text "rts_mk" <> text (showFFIType t) unpackHObj :: Type -> SDoc -unpackHObj t = text "rts_get" <> showFFIType t +unpackHObj t = text "rts_get" <> text (showFFIType t) showStgType :: Type -> SDoc -showStgType t = text "Stg" <> showFFIType t +showStgType t = text "Hs" <> text (showFFIType t) -showFFIType :: Type -> SDoc -showFFIType t = text (getOccString (getName tc)) +showFFIType :: Type -> String +showFFIType t = getOccString (getName tc) where - tc = case splitTyConApp_maybe t of + tc = case tcSplitTyConApp_maybe (repType t) of Just (tc,_) -> tc Nothing -> pprPanic "showFFIType" (ppr t) + +#if !defined(x86_64_TARGET_ARCH) +insertRetAddr CCallConv args = ret_addr_arg : args +insertRetAddr _ args = args +#else +-- On x86_64 we insert the return address after the 6th +-- integer argument, because this is the point at which we +-- need to flush a register argument to the stack (See rts/Adjustor.c for +-- details). +insertRetAddr CCallConv args = go 0 args + where go 6 args = ret_addr_arg : args + go n (arg@(_,_,_,rep):args) + | I64 <- rep = arg : go (n+1) args + | otherwise = arg : go n args + go n [] = [] +insertRetAddr _ args = args +#endif + +ret_addr_arg = (text "original_return_addr", text "void*", undefined, + typeMachRep addrPrimTy) + +-- This function returns the primitive type associated with the boxed +-- type argument to a foreign export (eg. Int ==> Int#). It assumes +-- that all the types we are interested in have a single constructor +-- with a single primitive-typed argument, which is true for all of the legal +-- foreign export argument types (see TcType.legalFEArgTyCon). +getPrimTyOf :: Type -> Type +getPrimTyOf ty = + case splitProductType_maybe (repType ty) of + Just (_, _, data_con, [prim_ty]) -> + ASSERT(dataConSourceArity data_con == 1) + ASSERT2(isUnLiftedType prim_ty, ppr prim_ty) + prim_ty + _other -> pprPanic "DsForeign.getPrimTyOf" (ppr ty) \end{code}