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, mkVanillaGlobal, mkSysLocal,
setInlinePragma )
-import IdInfo ( neverInlinePrag, vanillaIdInfo )
+import IdInfo ( vanillaIdInfo )
import Literal ( Literal(..) )
import Module ( Module, moduleUserString )
import Name ( mkGlobalName, nameModule, nameOccName, getOccString,
mkForeignExportOcc, isLocalName,
NamedThing(..),
)
-import Type ( repType, splitTyConApp_maybe,
- splitFunTys, splitForAllTys,
- Type, mkFunTys, mkForAllTys, mkTyConApp,
- mkFunTy, splitAppTy, applyTy, funResultTy
+import Type ( repType, eqType )
+import TcType ( Type, mkFunTys, mkForAllTys, mkTyConApp,
+ mkFunTy, applyTy,
+ tcSplitForAllTys, tcSplitFunTys, tcTyConAppArgs,
+ tcSplitTyConApp_maybe, tcSplitAppTy,
+ tcFunResultTy
)
-import PrimOp ( CCall(..), CCallTarget(..), dynamicTarget )
-import TysWiredIn ( unitTy, addrTy, stablePtrTyCon )
+
+import ForeignCall ( ForeignCall(..), CCallSpec(..),
+ Safety(..), playSafe,
+ CExportSpec(..),
+ CCallConv(..), ccallConvToInt,
+ ccallConvAttribute
+ )
+import CStrings ( CLabelString )
+import TysWiredIn ( addrTy, unitTy, stablePtrTyCon )
import TysPrim ( addrPrimTy )
import PrelNames ( hasKey, ioTyConKey, deRefStablePtrName, newStablePtrName,
bindIOName, returnIOName
)
+import BasicTypes ( Activation( NeverActive ) )
+import ErrUtils ( addShortWarnLocLine )
import Outputable
-
import Maybe ( fromJust )
\end{code}
-- "foreign exported" functions.
, SDoc -- C stubs to use when calling
-- "foreign exported" functions.
+ , [FAST_STRING] -- headers that need to be included
+ -- into C code generated for this module
)
-dsForeigns mod_name fos = foldlDs combine ([], [], empty, empty) fos
+dsForeigns mod_name fos
+ = foldlDs combine ([], [], 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 (acc_feb, acc_f, acc_h, acc_c, acc_header)
+ (ForeignImport id _ spec depr loc)
+ = dsFImport mod_name id spec `thenDs` \(bs, h, c, hd) ->
+ warnDepr depr loc `thenDs` \_ ->
+ returnDs (acc_feb, bs ++ acc_f, h $$ acc_h, c $$ acc_c, hd ++ acc_header)
+
+ combine (acc_feb, acc_f, acc_h, acc_c, acc_header)
+ (ForeignExport id _ (CExport (CExportStatic ext_nm cconv)) depr loc)
+ = dsFExport mod_name id (idType id)
+ ext_nm cconv False `thenDs` \(feb, b, h, c) ->
+ warnDepr depr loc `thenDs` \_ ->
+ returnDs (feb:acc_feb, b:acc_f, h $$ acc_h, c $$ acc_c, acc_header)
+
+ warnDepr False _ = returnDs ()
+ warnDepr True loc = dsWarn (addShortWarnLocLine loc msg)
where
- isForeignImport =
- case imp_exp of
- FoImport _ -> True
- _ -> False
+ msg = ptext SLIT("foreign declaration uses deprecated non-standard syntax")
+\end{code}
- isForeignLabel =
- case imp_exp of
- FoLabel -> True
- _ -> False
- (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
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 <=> cannot re-enter the Haskell RTS
- -> ExtName
- -> CallConv
- -> DsM [Binding]
-dsFImport fn_id ty unsafe ext_name cconv
+dsFImport :: Module
+ -> Id
+ -> ForeignImport
+ -> DsM ([Binding], SDoc, SDoc, [FAST_STRING])
+dsFImport modName id (CImport cconv safety header lib spec)
+ = dsCImport modName id spec cconv safety `thenDs` \(ids, h, c) ->
+ returnDs (ids, h, c, if _NULL_ header then [] else [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 `_NULL_ lib', the value was not given
+dsFImport modName id (DNImport spec)
+ = dsFCall modName id (DNCall spec) `thenDs` \(ids, h, c) ->
+ returnDs (ids, h, c, [])
+
+dsCImport :: Module
+ -> Id
+ -> CImportSpec
+ -> CCallConv
+ -> Safety
+ -> DsM ([Binding], SDoc, SDoc)
+dsCImport modName id (CLabel cid) _ _
+ = ASSERT(fromJust resTy `eqType` addrPrimTy) -- typechecker ensures this
+ returnDs ([(id, rhs)], empty, empty)
+ where
+ (resTy, foRhs) = resultWrapper (idType id)
+ rhs = foRhs (mkLit (MachLabel cid))
+dsCImport modName id (CFunction target) cconv safety
+ = dsFCall modName id (CCall (CCallSpec target cconv safety))
+dsCImport modName id CWrapper cconv _
+ = dsFExportDynamic modName id cconv
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsection{Foreign calls}
+%* *
+%************************************************************************
+
+\begin{code}
+dsFCall mod_Name fn_id fcall
= 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) ->
let
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
+ -- 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 = []
- | otherwise = work_arg_ids
+ maybe_arg_ids | unsafe_call fcall = work_arg_ids
+ | otherwise = []
in
- boxResult work_arg_ids io_res_ty `thenDs` \ (ccall_result_ty, res_wrapper) ->
+ boxResult maybe_arg_ids 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
-
-- Build the worker
worker_ty = mkForAllTys tvs (mkFunTys (map idType work_arg_ids) ccall_result_ty)
- the_ccall = CCall lbl False (not unsafe) 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("$wccall") work_uniq worker_ty
wrapper_body = foldr ($) (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
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
+dsFExport :: Module
+ -> 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 ( Id -- The foreign-exported Id
, Binding
, SDoc
, SDoc
)
-dsFExport fn_id ty mod_name ext_name cconv isDyn
+dsFExport mod_name fn_id ty 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
+ (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
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),
+ tcFunResultTy (applyTy (idType retIOId) orig_res_ty),
-- We don't have ioTyCon conveniently to hand
orig_res_ty)
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
+ ext_name
+ (if isDyn then Nothing else Just f_helper_glob)
+ fe_arg_tys res_ty cconv
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'
+ (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'
stbl_ptr_ty | isDyn = head fe_arg_tys'
| otherwise = error "stbl_ptr_ty"
+
+ (_, stbl_ptr_ty') = tcSplitForAllTys stbl_ptr_ty
+ (_, stbl_ptr_to_ty) = tcSplitAppTy stbl_ptr_ty'
+ -- Again, stable pointers are just newtypes,
+ -- so we must see them! Hence tcSplit*
\end{code}
@foreign export dynamic@ lets you dress up Haskell IO actions
\end{verbatim}
\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 ->
+dsFExportDynamic :: Module
+ -> Id
+ -> CCallConv
+ -> DsM ([Binding], SDoc, SDoc)
+dsFExportDynamic mod_name id cconv
+ = newSysLocalDs ty `thenDs` \ fe_id ->
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 = _PK_ (moduleUserString mod_name ++ "_" ++ toCName fe_id)
in
- dsFExport i export_ty mod_name fe_ext_name cconv True
- `thenDs` \ (feb, fe, h_code, c_code) ->
- newSysLocalDs arg_ty `thenDs` \ cback ->
- dsLookupGlobalValue newStablePtrName `thenDs` \ newStablePtrId ->
+ dsFExport mod_name id export_ty fe_nm cconv True `thenDs` \ ({-feb-}_, {-fe-}_, h_code, c_code) ->
+ newSysLocalDs arg_ty `thenDs` \ cback ->
+ dsLookupGlobalValue newStablePtrName `thenDs` \ newStablePtrId ->
let
mk_stbl_ptr_app = mkApps (Var newStablePtrId) [ Type arg_ty, Var cback ]
in
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)
]
-- name of external entry point providing these services.
-- (probably in the RTS.)
adjustor = SLIT("createAdjustor")
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] {-[fed, fe]-}, 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)))
\begin{code}
fexportEntry :: String
-> FAST_STRING
- -> Id
+ -> Maybe Id -- Just==static, Nothing==dynamic
-> [Type]
-> Type
- -> CallConv
- -> Bool
+ -> CCallConv
-> (SDoc, SDoc)
-fexportEntry mod_nm c_nm helper args res_ty cc isDyn = (header_bits, c_bits)
+fexportEntry mod_nm c_nm maybe_target arg_htys res_hty cc = (header_bits, c_bits)
where
- -- name of the (Haskell) helper function generated by the desugarer.
- h_nm = ppr helper <> text "_closure"
- -- prototype for the exported function.
+ -- 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_ctys
+ = case maybe_target of
+ Nothing -> [(text "the_stableptr", text "StgStablePtr")]
+ other -> []
+ ++
+ case (maybe_target, cc) of
+ (Nothing, CCallConv) -> [(text "original_return_addr", text "void*")]
+ other -> []
+
+ all_cnames_and_ctys :: [(SDoc, SDoc)]
+ all_cnames_and_ctys
+ = extra_cnames_and_ctys ++ zip arg_cnames arg_ctys
+
+ -- 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)
+
header_bits = ptext SLIT("extern") <+> fun_proto <> semi
fun_proto = cResType <+> pprCconv <+> ptext c_nm <>
- parens (hsep (punctuate comma (zipWith (<+>) cParamTypes proto_args)))
-
+ 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 -> 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;"
+
+ return_what | res_hty_is_unit = empty
+ | otherwise = parens (unpackHObj res_hty <> parens (text "ret"))
+
+ -- 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 $$
+ extern_decl $$
fun_proto $$
vcat
[ lbrace
, text "SchedulerStatus rc;"
, declareResult
-- 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 "rc=rts_evalIO"
+ <> parens (expr_to_run <+> comma <> text "&ret")
+ <> semi
, text "rts_checkSchedStatus" <> parens (doubleQuotes (ptext c_nm)
<> comma <> text "rc") <> semi
, text "return" <> return_what <> semi
, 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..]
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}
projects / ghc-hetmet.git / blobdiff