X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FdeSugar%2FDsForeign.lhs;h=2d4eb35ef59cba261e039509d98c66b4be3fb751;hb=a7d8f43718b167689c0a4a4c23b33a325e0239f1;hp=65ddba6e58cb4f6f1a62da7b8e7a576bd1820b17;hpb=9f6ed71a50e2d2084f664793f4f39ce815cad17f;p=ghc-hetmet.git diff --git a/ghc/compiler/deSugar/DsForeign.lhs b/ghc/compiler/deSugar/DsForeign.lhs index 65ddba6..2d4eb35 100644 --- a/ghc/compiler/deSugar/DsForeign.lhs +++ b/ghc/compiler/deSugar/DsForeign.lhs @@ -12,37 +12,42 @@ module DsForeign ( dsForeigns ) where import CoreSyn -import DsCCall ( dsCCall, mkCCall, boxResult, unboxArg, resultWrapper ) +import DsCCall ( dsCCall, mkFCall, boxResult, unboxArg, resultWrapper ) import DsMonad -import HsSyn ( ExtName(..), ForeignDecl(..), isDynamicExtName, ForKind(..) ) -import HsDecls ( extNameStatic ) -import CallConv +import HsSyn ( ForeignDecl(..), ForeignExport(..), + ForeignImport(..), CImportSpec(..) ) import TcHsSyn ( TypecheckedForeignDecl ) import CoreUtils ( exprType, mkInlineMe ) -import Id ( Id, idType, idName, mkVanillaId, mkSysLocal, - setInlinePragma ) -import IdInfo ( neverInlinePrag ) +import Id ( Id, idType, idName, mkSysLocal, setInlinePragma ) import Literal ( Literal(..) ) -import Module ( Module, moduleUserString ) -import Name ( mkGlobalName, nameModule, nameOccName, getOccString, - mkForeignExportOcc, isLocalName, - NamedThing(..), +import Module ( moduleString ) +import Name ( getOccString, NamedThing(..) ) +import OccName ( encodeFS ) +import Type ( repType, eqType, typePrimRep ) +import TcType ( Type, mkFunTys, mkForAllTys, mkTyConApp, + mkFunTy, tcSplitTyConApp_maybe, + tcSplitForAllTys, tcSplitFunTys, tcTyConAppArgs, ) -import Type ( repType, splitTyConApp_maybe, - tyConAppTyCon, splitFunTys, splitForAllTys, - Type, mkFunTys, mkForAllTys, mkTyConApp, - mkFunTy, splitAppTy, applyTy, funResultTy - ) -import PrimOp ( CCall(..), CCallTarget(..), dynamicTarget ) -import TysWiredIn ( unitTy, addrTy, stablePtrTyCon ) -import TysPrim ( addrPrimTy ) -import PrelNames ( hasKey, ioTyConKey, deRefStablePtrName, newStablePtrName, - bindIOName, returnIOName + +import BasicTypes ( Boxity(..) ) +import HscTypes ( ForeignStubs(..) ) +import ForeignCall ( ForeignCall(..), CCallSpec(..), + Safety(..), playSafe, + CExportSpec(..), + CCallConv(..), ccallConvToInt, + ccallConvAttribute ) +import CStrings ( CLabelString ) +import TysWiredIn ( unitTy, stablePtrTyCon, tupleTyCon ) +import TysPrim ( addrPrimTy, mkStablePtrPrimTy, alphaTy ) +import PrimRep ( getPrimRepSizeInBytes ) +import PrelNames ( hasKey, ioTyConKey, newStablePtrName, bindIOName, + checkDotnetResName ) +import BasicTypes ( Activation( NeverActive ) ) import Outputable - import Maybe ( fromJust ) +import FastString \end{code} Desugaring of @foreign@ declarations is naturally split up into @@ -62,46 +67,48 @@ so we reuse the desugaring code in @DsCCall@ to deal with these. type Binding = (Id, CoreExpr) -- No rec/nonrec structure; -- the occurrence analyser will sort it all out -dsForeigns :: Module - -> [TypecheckedForeignDecl] - -> DsM ( [Id] -- Foreign-exported binders; - -- we have to generate code to register these - , [Binding] - , SDoc -- Header file prototypes for - -- "foreign exported" functions. - , SDoc -- C stubs to use when calling - -- "foreign exported" functions. - ) -dsForeigns mod_name fos = foldlDs combine ([], [], empty, empty) fos +dsForeigns :: [TypecheckedForeignDecl] + -> DsM (ForeignStubs, [Binding]) +dsForeigns [] + = returnDs (NoStubs, []) +dsForeigns fos + = foldlDs combine (ForeignStubs empty empty [] [], []) fos where - combine (acc_feb, acc_f, 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` \ bs -> - returnDs (acc_feb, bs ++ acc_f, acc_h, acc_c) - | isForeignLabel = - dsFLabel i (idType i) ext_nm `thenDs` \ b -> - returnDs (acc_feb, b:acc_f, acc_h, acc_c) - | isDynamicExtName ext_nm = - dsFExportDynamic i (idType i) mod_name ext_nm cconv `thenDs` \ (feb,bs,h,c) -> - returnDs (feb:acc_feb, bs ++ acc_f, h $$ acc_h, c $$ acc_c) - - | otherwise = -- foreign export - dsFExport i (idType i) mod_name ext_nm cconv False `thenDs` \ (feb,fe,h,c) -> - returnDs (feb:acc_feb, fe:acc_f, h $$ acc_h, c $$ acc_c) + combine (ForeignStubs acc_h acc_c acc_hdrs acc_feb, acc_f) + (ForeignImport id _ spec depr loc) + = dsFImport id spec `thenDs` \ (bs, h, c, mbhd) -> + warnDepr depr loc `thenDs` \ _ -> + returnDs (ForeignStubs (h $$ acc_h) + (c $$ acc_c) + (addH mbhd acc_hdrs) + acc_feb, + bs ++ acc_f) + + combine (ForeignStubs acc_h acc_c acc_hdrs acc_feb, acc_f) + (ForeignExport id _ (CExport (CExportStatic ext_nm cconv)) depr loc) + = dsFExport id (idType id) + ext_nm cconv False `thenDs` \(h, c, _) -> + warnDepr depr loc `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 loc = dsWarn (loc, msg) where - isForeignImport = - case imp_exp of - FoImport _ -> True - _ -> False - - isForeignLabel = - case imp_exp of - FoLabel -> True - _ -> False + msg = ptext SLIT("foreign declaration uses deprecated non-standard syntax") +\end{code} - (FoImport uns) = imp_exp -\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 @@ -120,58 +127,140 @@ However, we create a worker/wrapper pair, thus: 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. - \begin{code} dsFImport :: Id - -> Type -- Type of foreign import. - -> Bool -- True <=> might cause Haskell GC - -> ExtName - -> CallConv - -> DsM [Binding] -dsFImport fn_id ty may_not_gc ext_name cconv + -> 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 = nullFastString 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 `eqType` 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} + + +%************************************************************************ +%* * +\subsection{Foreign calls} +%* * +%************************************************************************ + +\begin{code} +dsFCall fn_id fcall no_hdrs = let - (tvs, fun_ty) = splitForAllTys ty - (arg_tys, io_res_ty) = splitFunTys fun_ty + 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 newSysLocalsDs arg_tys `thenDs` \ args -> mapAndUnzipDs unboxArg (map Var args) `thenDs` \ (val_args, arg_wrappers) -> - boxResult io_res_ty `thenDs` \ (ccall_result_ty, res_wrapper) -> - getUniqueDs `thenDs` \ ccall_uniq -> - getUniqueDs `thenDs` \ work_uniq -> let - lbl = case ext_name of - Dynamic -> dynamicTarget - ExtName fs _ -> StaticTarget fs + work_arg_ids = [v | Var v <- val_args] -- All guaranteed to be vars + + -- These are the ids we pass to boxResult, which are used to decide + -- whether to touch# an argument after the call (used to keep + -- ForeignObj#s live across a 'safe' foreign import). + maybe_arg_ids | unsafe_call fcall = work_arg_ids + | otherwise = [] + + 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 + augmentResultDs `thenDs` \ augment -> + topConDs `thenDs` \ topCon -> + boxResult maybe_arg_ids augment topCon io_res_ty `thenDs` \ (ccall_result_ty, res_wrapper) -> + getUniqueDs `thenDs` \ ccall_uniq -> + getUniqueDs `thenDs` \ work_uniq -> + let -- Build the worker - work_arg_ids = [v | Var v <- val_args] -- All guaranteed to be vars worker_ty = mkForAllTys tvs (mkFunTys (map idType work_arg_ids) ccall_result_ty) - the_ccall = CCall lbl False (not may_not_gc) cconv - the_ccall_app = mkCCall ccall_uniq the_ccall val_args 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 = mkSysLocal SLIT("$wccall") work_uniq worker_ty + work_id = setImpInline no_hdrs $ -- See comments with setImpInline + mkSysLocal (encodeFS 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)] + 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 -> Type -> ExtName -> DsM Binding -dsFLabel nm ty ext_name = - ASSERT(fromJust res_ty == addrPrimTy) -- typechecker ensures this - returnDs (nm, fo_rhs (mkLit (MachLabel enm))) - where - (res_ty, fo_rhs) = resultWrapper ty - enm = extNameStatic ext_name -\end{code} +%************************************************************************ +%* * +\subsection{Foreign export} +%* * +%************************************************************************ The function that does most of the work for `@foreign export@' declarations. (see below for the boilerplate code a `@foreign export@' declaration expands @@ -185,112 +274,50 @@ For each `@foreign export foo@' in a module M we generate: the user-written Haskell function `@M.foo@'. \begin{code} -dsFExport :: Id - -> Type -- Type of foreign export. - -> Module - -> ExtName - -> CallConv - -> Bool -- True => invoke IO action that's hanging off - -- the first argument's stable pointer - -> DsM ( Id -- The foreign-exported Id - , Binding - , 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 + , [Type] -- arguments expected by stub function. ) -dsFExport fn_id ty mod_name ext_name cconv isDyn - = -- BUILD THE returnIO WRAPPER, if necessary - -- Look at the result type of the exported function, orig_res_ty - -- If it's IO t, return (\x.x, IO t, t) - -- If it's plain t, return (\x.returnIO x, IO t, t) - (case splitTyConApp_maybe orig_res_ty of - Just (ioTyCon, [res_ty]) - -> ASSERT( ioTyCon `hasKey` ioTyConKey ) - -- The function already returns IO t - returnDs (\body -> body, orig_res_ty, res_ty) - - other -> -- The function returns t, so wrap the call in returnIO - dsLookupGlobalValue returnIOName `thenDs` \ retIOId -> - returnDs (\body -> mkApps (Var retIOId) [Type orig_res_ty, body], - funResultTy (applyTy (idType retIOId) orig_res_ty), - -- We don't have ioTyCon conveniently to hand - orig_res_ty) - - ) `thenDs` \ (return_io_wrapper, -- Either identity or returnIO - io_res_ty, -- IO t - res_ty) -> -- t - - - -- BUILD THE deRefStablePtr WRAPPER, if necessary - (if isDyn then - newSysLocalDs stbl_ptr_ty `thenDs` \ stbl_ptr -> - newSysLocalDs stbl_ptr_to_ty `thenDs` \ stbl_value -> - dsLookupGlobalValue deRefStablePtrName `thenDs` \ deRefStablePtrId -> - dsLookupGlobalValue bindIOName `thenDs` \ bindIOId -> - let - the_deref_app = mkApps (Var deRefStablePtrId) - [ Type stbl_ptr_to_ty, Var stbl_ptr ] - - stbl_app cont = mkApps (Var bindIOId) - [ Type stbl_ptr_to_ty - , Type res_ty - , the_deref_app - , mkLams [stbl_value] cont] - in - returnDs (stbl_value, stbl_app, stbl_ptr) - else - returnDs (fn_id, - \ body -> body, - panic "stbl_ptr" -- should never be touched. - )) `thenDs` \ (i, getFun_wrapper, stbl_ptr) -> - - - -- BUILD THE HELPER - getModuleDs `thenDs` \ mod -> - getUniqueDs `thenDs` \ uniq -> - getSrcLocDs `thenDs` \ src_loc -> - newSysLocalsDs fe_arg_tys `thenDs` \ fe_args -> + +dsFExport fn_id ty ext_name cconv isDyn + = let - wrapper_args | isDyn = stbl_ptr:fe_args - | otherwise = fe_args - - wrapper_arg_tys | isDyn = stbl_ptr_ty:fe_arg_tys - | otherwise = fe_arg_tys - - helper_ty = mkForAllTys tvs $ - mkFunTys wrapper_arg_tys io_res_ty - - f_helper_glob = mkVanillaId helper_name helper_ty - where - name = idName fn_id - mod - | isLocalName name = mod_name - | otherwise = nameModule name - - occ = mkForeignExportOcc (nameOccName name) - helper_name = mkGlobalName uniq mod occ src_loc - - the_app = getFun_wrapper (return_io_wrapper (mkVarApps (Var i) (tvs ++ fe_args))) - the_body = mkLams (tvs ++ wrapper_args) the_app - c_nm = extNameStatic ext_name - - (h_stub, c_stub) = fexportEntry (moduleUserString mod) - c_nm f_helper_glob - wrapper_arg_tys res_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 (f_helper_glob, (f_helper_glob, the_body), h_stub, c_stub) - - where - (tvs,sans_foralls) = splitForAllTys ty - (fe_arg_tys', orig_res_ty) = splitFunTys sans_foralls - - (_, 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' + -- 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.] - stbl_ptr_ty | isDyn = head fe_arg_tys' - | otherwise = error "stbl_ptr_ty" + 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 @@ -317,26 +344,22 @@ foreign export "f_helper" f_helper :: StablePtr (Addr -> Int -> IO Int) -> Addr \begin{code} dsFExportDynamic :: Id - -> Type -- Type of foreign export. - -> Module - -> ExtName - -> CallConv - -> DsM (Id, [Binding], SDoc, SDoc) -dsFExportDynamic i ty mod_name 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 = moduleUserString mod_name ++ "_" ++ toCName fe_id - fe_ext_name = ExtName (_PK_ fe_nm) Nothing + fe_nm = mkFastString (moduleString mod_name ++ "_" ++ toCName fe_id) in - dsFExport i export_ty mod_name fe_ext_name cconv True - `thenDs` \ (feb, fe, h_code, c_code) -> + dsFExport id export_ty fe_nm cconv True `thenDs` \ (h_code, c_code, stub_args) -> newSysLocalDs arg_ty `thenDs` \ cback -> - dsLookupGlobalValue newStablePtrName `thenDs` \ newStablePtrId -> + dsLookupGlobalId newStablePtrName `thenDs` \ newStablePtrId -> let mk_stbl_ptr_app = mkApps (Var newStablePtrId) [ Type arg_ty, Var cback ] in - dsLookupGlobalValue bindIOName `thenDs` \ bindIOId -> + dsLookupGlobalId bindIOName `thenDs` \ bindIOId -> newSysLocalDs (mkTyConApp stablePtrTyCon [arg_ty]) `thenDs` \ stbl_value -> let stbl_app cont ret_ty @@ -354,39 +377,41 @@ dsFExportDynamic i ty mod_name ext_name cconv = to be entered using an external calling convention (stdcall, ccall). -} - adj_args = [ mkIntLitInt (callConvToInt cconv) + adj_args = [ mkIntLitInt (ccallConvToInt cconv) , Var stbl_value - , mkLit (MachLabel (_PK_ fe_nm)) + , mkLit (MachLabel fe_nm mb_sz_args) ] -- name of external entry point providing these services. -- (probably in the RTS.) - adjustor = SLIT("createAdjustor") + adjustor = FSLIT("createAdjustor") + + mb_sz_args = + case cconv of + StdCallConv -> Just (sum (map (getPrimRepSizeInBytes . typePrimRep) stub_args)) + _ -> Nothing in - dsCCall adjustor adj_args False False io_res_ty `thenDs` \ ccall_adj -> + dsCCall adjustor adj_args PlayRisky False 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 - in - let io_app = mkLams tvs $ + io_app = mkLams tvs $ mkLams [cback] $ stbl_app ccall_io_adj res_ty - fed = (i `setInlinePragma` neverInlinePrag, io_app) + 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 (feb, [fed, fe], h_code, c_code) + returnDs ([fed], h_code, c_code) where - (tvs,sans_foralls) = splitForAllTys ty - ([arg_ty], io_res_ty) = splitFunTys sans_foralls - - Just (ioTyCon, [res_ty]) = splitTyConApp_maybe io_res_ty - - export_ty = mkFunTy (mkTyConApp stablePtrTyCon [arg_ty]) arg_ty - - ioAddrTy :: Type -- IO Addr - ioAddrTy = mkTyConApp ioTyCon [addrTy] + 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 + export_ty = mkFunTy (mkTyConApp stablePtrTyCon [arg_ty]) arg_ty toCName :: Id -> String toCName i = showSDoc (pprCode CStyle (ppr (idName i))) @@ -403,76 +428,117 @@ The C stub constructs the application of the exported Haskell function using the hugs/ghc rts invocation API. \begin{code} -fexportEntry :: String - -> FAST_STRING - -> Id - -> [Type] - -> Type - -> CallConv - -> Bool - -> (SDoc, SDoc) -fexportEntry mod_nm c_nm helper args res_ty 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, [Type]) +mkFExportCBits c_nm maybe_target arg_htys res_hty is_IO_res_ty cc + = (header_bits, c_bits, all_arg_tys) where - -- name of the (Haskell) helper function generated by the desugarer. - h_nm = ppr helper <> text "_closure" - -- prototype for the exported function. - header_bits = ptext SLIT("extern") <+> fun_proto <> semi + -- Create up types and names for the real args + arg_cnames, arg_ctys :: [SDoc] + arg_cnames = mkCArgNames 1 arg_htys + arg_ctys = map showStgType arg_htys + + -- and also for auxiliary ones; the stable ptr in the dynamic case, and + -- a slot for the dummy return address in the dynamic + ccall case + extra_cnames_and_tys + = case maybe_target of + Nothing -> [((text "the_stableptr", text "StgStablePtr"), mkStablePtrPrimTy alphaTy)] + other -> [] + ++ + case (maybe_target, cc) of + (Nothing, CCallConv) -> [((text "original_return_addr", text "void*"), addrPrimTy)] + other -> [] + + all_cnames_and_ctys :: [(SDoc, SDoc)] + all_cnames_and_ctys + = map fst extra_cnames_and_tys ++ zip arg_cnames arg_ctys + + all_arg_tys + = map snd extra_cnames_and_tys ++ arg_htys + + -- stuff to do with the return type of the C function + res_hty_is_unit = res_hty `eqType` 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) - fun_proto = cResType <+> pprCconv <+> ptext c_nm <> - parens (hsep (punctuate comma (zipWith (<+>) cParamTypes proto_args))) + header_bits = ptext SLIT("extern") <+> fun_proto <> semi + fun_proto = cResType <+> pprCconv <+> ftext c_nm <> + parens (hsep (punctuate comma (map (\(nm,ty) -> ty <+> nm) + all_cnames_and_ctys))) + + -- 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" + + -- the expression we give to rts_evalIO + expr_to_run + = foldl appArg the_cfun (zip arg_cnames arg_htys) + where + appArg acc (arg_cname, arg_hty) + = text "rts_apply" + <> parens (acc <> comma <> mkHObj arg_hty <> parens 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 + + -- finally, the whole darn thing c_bits = - externDecl $$ + space $$ + extern_decl $$ fun_proto $$ vcat [ lbrace , text "SchedulerStatus rc;" , declareResult + , declareCResult + , text "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 - , text "rts_checkSchedStatus" <> parens (doubleQuotes (ptext c_nm) + , text "rc=rts_evalIO" <> parens ( + text "rts_apply" <> parens ( + 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 "rc") <> semi - , text "return" <> return_what <> semi + , assignCResult + , text "rts_unlock();" + , 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 - - res_ty_is_unit = res_ty == unitTy - - cResType | res_ty_is_unit = text "void" - | otherwise = showStgType res_ty - - 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 - - return_what | res_ty_is_unit = empty - | otherwise = parens (unpackHObj res_ty <> 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 :: Int -> [a] -> [SDoc] mkCArgNames n as = zipWith (\ _ n -> text ('a':show n)) as [n..] @@ -489,7 +555,7 @@ showStgType t = text "Hs" <> text (showFFIType t) showFFIType :: Type -> String showFFIType t = getOccString (getName tc) where - tc = case splitTyConApp_maybe (repType t) of + tc = case tcSplitTyConApp_maybe (repType t) of Just (tc,_) -> tc Nothing -> pprPanic "showFFIType" (ppr t) \end{code}