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
\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
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}
%*
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}
projects / ghc-hetmet.git / blobdiff