{-# OPTIONS_GHC -Wno-incomplete-uni-patterns #-}

-- | Handling of C foreign imports/exports
module GHC.HsToCore.Foreign.C
  ( dsCImport
  , dsCFExport
  , dsCFExportDynamic
  )
where

import GHC.Prelude

import GHC.Platform

import GHC.Tc.Utils.Monad        -- temp
import GHC.Tc.Utils.Env
import GHC.Tc.Utils.TcType

import GHC.Core
import GHC.Core.Unfold.Make
import GHC.Core.Type
import GHC.Core.TyCon
import GHC.Core.Coercion
import GHC.Core.Multiplicity

import GHC.HsToCore.Foreign.Call
import GHC.HsToCore.Foreign.Prim
import GHC.HsToCore.Foreign.Utils
import GHC.HsToCore.Monad
import GHC.HsToCore.Types (ds_next_wrapper_num)

import GHC.Hs

import GHC.Types.Id
import GHC.Types.Literal
import GHC.Types.ForeignStubs
import GHC.Types.SourceText
import GHC.Types.Name
import GHC.Types.RepType
import GHC.Types.ForeignCall
import GHC.Types.Basic

import GHC.Unit.Module

import GHC.Driver.DynFlags
import GHC.Driver.Config

import GHC.Cmm.Expr
import GHC.Cmm.Utils

import GHC.Builtin.Types
import GHC.Builtin.Types.Prim
import GHC.Builtin.Names

import GHC.Data.FastString

import GHC.Utils.Outputable
import GHC.Utils.Panic
import GHC.Utils.Panic.Plain
import GHC.Utils.Encoding

import Data.Maybe
import Data.List (nub)

dsCFExport:: Id                 -- Either the exported Id,
                                -- or the foreign-export-dynamic constructor
          -> Coercion           -- Coercion between the Haskell type callable
                                -- from C, and its representation type
          -> 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 ( CHeader      -- contents of Module_stub.h
                 , CStub        -- contents of Module_stub.c
                 , String       -- string describing type to pass to createAdj.
                 , Int          -- size of args to stub function
                 )

dsCFExport :: Id
-> Coercion
-> CLabelString
-> CCallConv
-> Bool
-> DsM (CHeader, CStub, String, Int)
dsCFExport Id
fn_id Coercion
co CLabelString
ext_name CCallConv
cconv Bool
isDyn = do
    let
       ty :: Type
ty                     = Coercion -> Type
coercionRKind Coercion
co
       ([PiTyVarBinder]
bndrs, Type
orig_res_ty)   = Type -> ([PiTyVarBinder], Type)
tcSplitPiTys Type
ty
       fe_arg_tys' :: [Type]
fe_arg_tys'            = (PiTyVarBinder -> Maybe Type) -> [PiTyVarBinder] -> [Type]
forall a b. (a -> Maybe b) -> [a] -> [b]
mapMaybe PiTyVarBinder -> Maybe Type
anonPiTyBinderType_maybe [PiTyVarBinder]
bndrs
       -- We must use tcSplits here, because we want to see
       -- the (IO t) in the corner of the type!
       fe_arg_tys :: [Type]
fe_arg_tys | Bool
isDyn     = [Type] -> [Type]
forall a. HasCallStack => [a] -> [a]
tail [Type]
fe_arg_tys'
                  | Bool
otherwise = [Type]
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)
       (Type
res_ty, Bool
is_IO_res_ty) = case Type -> Maybe (TyCon, Type)
tcSplitIOType_maybe Type
orig_res_ty of
                                -- The function already returns IO t
                                Just (TyCon
_ioTyCon, Type
res_ty) -> (Type
res_ty, Bool
True)
                                -- The function returns t
                                Maybe (TyCon, Type)
Nothing                 -> (Type
orig_res_ty, Bool
False)

    DynFlags
dflags <- IOEnv (Env DsGblEnv DsLclEnv) DynFlags
forall (m :: * -> *). HasDynFlags m => m DynFlags
getDynFlags
    (CHeader, CStub, String, Int) -> DsM (CHeader, CStub, String, Int)
forall a. a -> IOEnv (Env DsGblEnv DsLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return ((CHeader, CStub, String, Int)
 -> DsM (CHeader, CStub, String, Int))
-> (CHeader, CStub, String, Int)
-> DsM (CHeader, CStub, String, Int)
forall a b. (a -> b) -> a -> b
$
      DynFlags
-> CLabelString
-> Maybe Id
-> [Type]
-> Type
-> Bool
-> CCallConv
-> (CHeader, CStub, String, Int)
mkFExportCBits DynFlags
dflags CLabelString
ext_name
                     (if Bool
isDyn then Maybe Id
forall a. Maybe a
Nothing else Id -> Maybe Id
forall a. a -> Maybe a
Just Id
fn_id)
                     [Type]
fe_arg_tys Type
res_ty Bool
is_IO_res_ty CCallConv
cconv

dsCImport :: Id
          -> Coercion
          -> CImportSpec
          -> CCallConv
          -> Safety
          -> Maybe Header
          -> DsM ([Binding], CHeader, CStub)
dsCImport :: Id
-> Coercion
-> CImportSpec
-> CCallConv
-> Safety
-> Maybe Header
-> DsM ([Binding], CHeader, CStub)
dsCImport Id
id Coercion
co (CLabel CLabelString
cid) CCallConv
cconv Safety
_ Maybe Header
_ = do
   DynFlags
dflags <- IOEnv (Env DsGblEnv DsLclEnv) DynFlags
forall (m :: * -> *). HasDynFlags m => m DynFlags
getDynFlags
   let ty :: Type
ty  = Coercion -> Type
coercionLKind Coercion
co
       platform :: Platform
platform = DynFlags -> Platform
targetPlatform DynFlags
dflags
       fod :: FunctionOrData
fod = case Type -> Maybe TyCon
tyConAppTyCon_maybe (Type -> Type
dropForAlls Type
ty) of
             Just TyCon
tycon
              | TyCon -> Unique
tyConUnique TyCon
tycon Unique -> Unique -> Bool
forall a. Eq a => a -> a -> Bool
== Unique
funPtrTyConKey ->
                 FunctionOrData
IsFunction
             Maybe TyCon
_ -> FunctionOrData
IsData
   (Maybe Type
resTy, CoreExpr -> CoreExpr
foRhs) <- Type -> DsM (Maybe Type, CoreExpr -> CoreExpr)
resultWrapper Type
ty
   Bool
-> DsM ([Binding], CHeader, CStub)
-> DsM ([Binding], CHeader, CStub)
forall a. HasCallStack => Bool -> a -> a
assert (Maybe Type -> Type
forall a. HasCallStack => Maybe a -> a
fromJust Maybe Type
resTy Type -> Type -> Bool
`eqType` Type
addrPrimTy) (DsM ([Binding], CHeader, CStub)
 -> DsM ([Binding], CHeader, CStub))
-> DsM ([Binding], CHeader, CStub)
-> DsM ([Binding], CHeader, CStub)
forall a b. (a -> b) -> a -> b
$    -- typechecker ensures this
    let
        rhs :: CoreExpr
rhs = CoreExpr -> CoreExpr
foRhs (Literal -> CoreExpr
forall b. Literal -> Expr b
Lit (CLabelString -> Maybe Int -> FunctionOrData -> Literal
LitLabel CLabelString
cid Maybe Int
stdcall_info FunctionOrData
fod))
        rhs' :: CoreExpr
rhs' = CoreExpr -> Coercion -> CoreExpr
forall b. Expr b -> Coercion -> Expr b
Cast CoreExpr
rhs Coercion
co
        stdcall_info :: Maybe Int
stdcall_info = Platform -> CCallConv -> Type -> Maybe Int
fun_type_arg_stdcall_info Platform
platform CCallConv
cconv Type
ty
    in
    ([Binding], CHeader, CStub) -> DsM ([Binding], CHeader, CStub)
forall a. a -> IOEnv (Env DsGblEnv DsLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return ([(Id
id, CoreExpr
rhs')], CHeader
forall a. Monoid a => a
mempty, CStub
forall a. Monoid a => a
mempty)

dsCImport Id
id Coercion
co (CFunction CCallTarget
target) cconv :: CCallConv
cconv@CCallConv
PrimCallConv Safety
safety Maybe Header
_
  = Id -> Coercion -> ForeignCall -> DsM ([Binding], CHeader, CStub)
dsPrimCall Id
id Coercion
co (CCallSpec -> ForeignCall
CCall (CCallTarget -> CCallConv -> Safety -> CCallSpec
CCallSpec CCallTarget
target CCallConv
cconv Safety
safety))
dsCImport Id
id Coercion
co (CFunction CCallTarget
target) CCallConv
cconv Safety
safety Maybe Header
mHeader
  = Id
-> Coercion
-> ForeignCall
-> Maybe Header
-> DsM ([Binding], CHeader, CStub)
dsFCall Id
id Coercion
co (CCallSpec -> ForeignCall
CCall (CCallTarget -> CCallConv -> Safety -> CCallSpec
CCallSpec CCallTarget
target CCallConv
cconv Safety
safety)) Maybe Header
mHeader
dsCImport Id
id Coercion
co CImportSpec
CWrapper CCallConv
cconv Safety
_ Maybe Header
_
  = Id -> Coercion -> CCallConv -> DsM ([Binding], CHeader, CStub)
dsCFExportDynamic Id
id Coercion
co CCallConv
cconv


{-
@foreign import "wrapper"@ (previously "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}
type Fun = Bool -> Int -> IO Int
foreign import "wrapper" f :: Fun -> IO (FunPtr Fun)

-- Haskell-visible constructor, which is generated from the above:
-- SUP: No check for NULL from createAdjustor anymore???

f :: Fun -> IO (FunPtr Fun)
f cback =
   bindIO (newStablePtr cback)
          (\StablePtr sp# -> IO (\s1# ->
              case _ccall_ createAdjustor cconv sp# ``f_helper'' <arg info> s1# of
                 (# s2#, a# #) -> (# s2#, A# a# #)))

foreign import "&f_helper" f_helper :: FunPtr (StablePtr Fun -> Fun)

-- and the helper in C: (approximately; see `mkFExportCBits` below)

f_helper(StablePtr s, HsBool b, HsInt i)
{
        Capability *cap;
        cap = rts_lock();
        rts_inCall(&cap,
                   rts_apply(rts_apply(deRefStablePtr(s),
                                       rts_mkBool(b)), rts_mkInt(i)));
        rts_unlock(cap);
}
\end{verbatim}
-}
dsCFExportDynamic :: Id
                 -> Coercion
                 -> CCallConv
                 -> DsM ([Binding], CHeader, CStub)
dsCFExportDynamic :: Id -> Coercion -> CCallConv -> DsM ([Binding], CHeader, CStub)
dsCFExportDynamic Id
id Coercion
co0 CCallConv
cconv = do
    Module
mod <- IOEnv (Env DsGblEnv DsLclEnv) Module
forall (m :: * -> *). HasModule m => m Module
getModule
    DynFlags
dflags <- IOEnv (Env DsGblEnv DsLclEnv) DynFlags
forall (m :: * -> *). HasDynFlags m => m DynFlags
getDynFlags
    let platform :: Platform
platform = DynFlags -> Platform
targetPlatform DynFlags
dflags
    let fe_nm :: CLabelString
fe_nm = String -> CLabelString
mkFastString (String -> CLabelString) -> String -> CLabelString
forall a b. (a -> b) -> a -> b
$ String -> String
zEncodeString
            (Module -> String
moduleStableString Module
mod String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"$" String -> String -> String
forall a. [a] -> [a] -> [a]
++ Id -> String
toCName Id
id)
        -- Construct the label based on the passed id, don't use names
        -- depending on Unique. See #13807 and Note [Unique Determinism].
    Id
cback <- Type -> Type -> DsM Id
newSysLocalDs Type
arg_mult Type
arg_ty
    Id
newStablePtrId <- Name -> DsM Id
dsLookupGlobalId Name
newStablePtrName
    TyCon
stable_ptr_tycon <- Name -> DsM TyCon
dsLookupTyCon Name
stablePtrTyConName
    let
        stable_ptr_ty :: Type
stable_ptr_ty = TyCon -> [Type] -> Type
mkTyConApp TyCon
stable_ptr_tycon [Type
arg_ty]
        export_ty :: Type
export_ty     = HasDebugCallStack => Type -> Type -> Type
Type -> Type -> Type
mkVisFunTyMany Type
stable_ptr_ty Type
arg_ty
    Id
bindIOId <- Name -> DsM Id
dsLookupGlobalId Name
bindIOName
    Id
stbl_value <- Type -> Type -> DsM Id
newSysLocalDs Type
ManyTy Type
stable_ptr_ty
    (CHeader
h_code, CStub
c_code, String
typestring, Int
args_size) <- Id
-> Coercion
-> CLabelString
-> CCallConv
-> Bool
-> DsM (CHeader, CStub, String, Int)
dsCFExport Id
id (Type -> Coercion
mkRepReflCo Type
export_ty) CLabelString
fe_nm CCallConv
cconv Bool
True
    let
         {-
          The arguments to the external function which will
          create a little bit of (template) code on the fly
          for allowing the (stable pointed) Haskell closure
          to be entered using an external calling convention
          (stdcall, ccall).
         -}
        adj_args :: [CoreExpr]
adj_args      = [ Platform -> Integer -> CoreExpr
forall b. Platform -> Integer -> Expr b
mkIntLit Platform
platform (Int -> Integer
forall a b. (Integral a, Num b) => a -> b
fromIntegral (CCallConv -> Int
ccallConvToInt CCallConv
cconv))
                        , Id -> CoreExpr
forall b. Id -> Expr b
Var Id
stbl_value
                        , Literal -> CoreExpr
forall b. Literal -> Expr b
Lit (CLabelString -> Maybe Int -> FunctionOrData -> Literal
LitLabel CLabelString
fe_nm Maybe Int
mb_sz_args FunctionOrData
IsFunction)
                        , Literal -> CoreExpr
forall b. Literal -> Expr b
Lit (String -> Literal
mkLitString String
typestring)
                        ]
          -- name of external entry point providing these services.
          -- (probably in the RTS.)
        adjustor :: CLabelString
adjustor   = String -> CLabelString
fsLit String
"createAdjustor"

          -- 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 :: Maybe Int
mb_sz_args = case CCallConv
cconv of
                        CCallConv
StdCallConv -> Int -> Maybe Int
forall a. a -> Maybe a
Just Int
args_size
                        CCallConv
_           -> Maybe Int
forall a. Maybe a
Nothing

    CoreExpr
ccall_adj <- CLabelString -> [CoreExpr] -> Safety -> Type -> DsM CoreExpr
dsCCall CLabelString
adjustor [CoreExpr]
adj_args Safety
PlayRisky (TyCon -> [Type] -> Type
mkTyConApp TyCon
io_tc [Type
res_ty])
        -- PlayRisky: the adjustor doesn't allocate in the Haskell heap or do a callback

    let io_app :: CoreExpr
io_app = [Id] -> CoreExpr -> CoreExpr
forall b. [b] -> Expr b -> Expr b
mkLams [Id]
tvs                  (CoreExpr -> CoreExpr) -> CoreExpr -> CoreExpr
forall a b. (a -> b) -> a -> b
$
                 Id -> CoreExpr -> CoreExpr
forall b. b -> Expr b -> Expr b
Lam Id
cback                   (CoreExpr -> CoreExpr) -> CoreExpr -> CoreExpr
forall a b. (a -> b) -> a -> b
$
                 CoreExpr -> [CoreExpr] -> CoreExpr
forall b. Expr b -> [Expr b] -> Expr b
mkApps (Id -> CoreExpr
forall b. Id -> Expr b
Var Id
bindIOId)
                        [ Type -> CoreExpr
forall b. Type -> Expr b
Type Type
stable_ptr_ty
                        , Type -> CoreExpr
forall b. Type -> Expr b
Type Type
res_ty
                        , CoreExpr -> [CoreExpr] -> CoreExpr
forall b. Expr b -> [Expr b] -> Expr b
mkApps (Id -> CoreExpr
forall b. Id -> Expr b
Var Id
newStablePtrId) [ Type -> CoreExpr
forall b. Type -> Expr b
Type Type
arg_ty, Id -> CoreExpr
forall b. Id -> Expr b
Var Id
cback ]
                        , Id -> CoreExpr -> CoreExpr
forall b. b -> Expr b -> Expr b
Lam Id
stbl_value CoreExpr
ccall_adj
                        ]

        fed :: Binding
fed = (Id
id Id -> Activation -> Id
`setInlineActivation` Activation
NeverActive, CoreExpr -> Coercion -> CoreExpr
forall b. Expr b -> Coercion -> Expr b
Cast CoreExpr
io_app Coercion
co0)
               -- Never inline the f.e.d. function, because the litlit
               -- might not be in scope in other modules.

    ([Binding], CHeader, CStub) -> DsM ([Binding], CHeader, CStub)
forall a. a -> IOEnv (Env DsGblEnv DsLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return ([Binding
fed], CHeader
h_code, CStub
c_code)

 where
  ty :: Type
ty                       = Coercion -> Type
coercionLKind Coercion
co0
  ([Id]
tvs,Type
sans_foralls)       = Type -> ([Id], Type)
tcSplitForAllInvisTyVars Type
ty
  ([Scaled Type
arg_mult Type
arg_ty], Type
fn_res_ty)    = Type -> ([Scaled Type], Type)
tcSplitFunTys Type
sans_foralls
  Just (TyCon
io_tc, Type
res_ty)     = Type -> Maybe (TyCon, Type)
tcSplitIOType_maybe Type
fn_res_ty
        -- Must have an IO type; hence Just


-- | Foreign calls
dsFCall :: Id -> Coercion -> ForeignCall -> Maybe Header
        -> DsM ([(Id, Expr TyVar)], CHeader, CStub)
dsFCall :: Id
-> Coercion
-> ForeignCall
-> Maybe Header
-> DsM ([Binding], CHeader, CStub)
dsFCall Id
fn_id Coercion
co ForeignCall
fcall Maybe Header
mDeclHeader = do
    let
        (Type
ty,Type
ty1)             = (Coercion -> Type
coercionLKind Coercion
co, Coercion -> Type
coercionRKind Coercion
co)
        ([TyVarBinder]
tv_bndrs, Type
rho)      = Type -> ([TyVarBinder], Type)
tcSplitForAllTyVarBinders Type
ty
        ([Scaled Type]
arg_tys, Type
io_res_ty) = Type -> ([Scaled Type], Type)
tcSplitFunTys Type
rho

    let constQual :: SDoc
constQual -- provide 'const' qualifier (#22043)
          | ([Scaled Type]
_, Type
res_ty1) <- Type -> ([Scaled Type], Type)
tcSplitFunTys Type
ty1
          , Type
newty <- Type -> ((TyCon, Type) -> Type) -> Maybe (TyCon, Type) -> Type
forall b a. b -> (a -> b) -> Maybe a -> b
maybe Type
res_ty1 (TyCon, Type) -> Type
forall a b. (a, b) -> b
snd (Type -> Maybe (TyCon, Type)
tcSplitIOType_maybe Type
res_ty1)
          , Just (TyCon
ptr, [Type]
_) <- HasDebugCallStack => Type -> Maybe (TyCon, [Type])
Type -> Maybe (TyCon, [Type])
splitTyConApp_maybe Type
newty
          , TyCon -> Name
tyConName TyCon
ptr Name -> Name -> Bool
forall a. Eq a => a -> a -> Bool
== Name
constPtrConName
          = String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"const"
          | Bool
otherwise = SDoc
forall doc. IsOutput doc => doc
empty

    [Id]
args <- [Scaled Type] -> DsM [Id]
newSysLocalsDs [Scaled Type]
arg_tys  -- no FFI representation polymorphism
    ([CoreExpr]
val_args, [CoreExpr -> CoreExpr]
arg_wrappers) <- (CoreExpr
 -> IOEnv (Env DsGblEnv DsLclEnv) (CoreExpr, CoreExpr -> CoreExpr))
-> [CoreExpr]
-> IOEnv
     (Env DsGblEnv DsLclEnv) ([CoreExpr], [CoreExpr -> CoreExpr])
forall (m :: * -> *) a b c.
Applicative m =>
(a -> m (b, c)) -> [a] -> m ([b], [c])
mapAndUnzipM CoreExpr
-> IOEnv (Env DsGblEnv DsLclEnv) (CoreExpr, CoreExpr -> CoreExpr)
unboxArg ((Id -> CoreExpr) -> [Id] -> [CoreExpr]
forall a b. (a -> b) -> [a] -> [b]
map Id -> CoreExpr
forall b. Id -> Expr b
Var [Id]
args)

    let
        work_arg_ids :: [Id]
work_arg_ids  = [Id
v | Var Id
v <- [CoreExpr]
val_args] -- All guaranteed to be vars

    (Type
ccall_result_ty, CoreExpr -> CoreExpr
res_wrapper) <- Type -> DsM (Type, CoreExpr -> CoreExpr)
boxResult Type
io_res_ty

    Unique
ccall_uniq <- TcRnIf DsGblEnv DsLclEnv Unique
forall gbl lcl. TcRnIf gbl lcl Unique
newUnique
    Unique
work_uniq  <- TcRnIf DsGblEnv DsLclEnv Unique
forall gbl lcl. TcRnIf gbl lcl Unique
newUnique

    (ForeignCall
fcall', SDoc
cDoc) <-
              case ForeignCall
fcall of
              CCall (CCallSpec (StaticTarget SourceText
_ CLabelString
cName Maybe Unit
mUnitId Bool
isFun)
                               CCallConv
CApiConv Safety
safety) ->
               do IORef (ModuleEnv Int)
nextWrapperNum <- DsGblEnv -> IORef (ModuleEnv Int)
ds_next_wrapper_num (DsGblEnv -> IORef (ModuleEnv Int))
-> IOEnv (Env DsGblEnv DsLclEnv) DsGblEnv
-> IOEnv (Env DsGblEnv DsLclEnv) (IORef (ModuleEnv Int))
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> IOEnv (Env DsGblEnv DsLclEnv) DsGblEnv
forall gbl lcl. TcRnIf gbl lcl gbl
getGblEnv
                  CLabelString
wrapperName <- IORef (ModuleEnv Int)
-> String -> String -> IOEnv (Env DsGblEnv DsLclEnv) CLabelString
forall (m :: * -> *).
(MonadIO m, HasModule m) =>
IORef (ModuleEnv Int) -> String -> String -> m CLabelString
mkWrapperName IORef (ModuleEnv Int)
nextWrapperNum String
"ghc_wrapper" (CLabelString -> String
unpackFS CLabelString
cName)
                  let fcall' :: ForeignCall
fcall' = CCallSpec -> ForeignCall
CCall (CCallTarget -> CCallConv -> Safety -> CCallSpec
CCallSpec
                                      (SourceText -> CLabelString -> Maybe Unit -> Bool -> CCallTarget
StaticTarget SourceText
NoSourceText
                                                    CLabelString
wrapperName Maybe Unit
mUnitId
                                                    Bool
True)
                                      CCallConv
CApiConv Safety
safety)
                      c :: SDoc
c = SDoc
includes
                       SDoc -> SDoc -> SDoc
forall doc. IsDoc doc => doc -> doc -> doc
$$ SDoc
fun_proto SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
braces (SDoc
cRet SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc
forall doc. IsLine doc => doc
semi)
                      includes :: SDoc
includes = [SDoc] -> SDoc
forall doc. IsDoc doc => [doc] -> doc
vcat [ String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"#include \"" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> CLabelString -> SDoc
forall doc. IsLine doc => CLabelString -> doc
ftext CLabelString
h
                                        SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"\""
                                      | Header SourceText
_ CLabelString
h <- [Header] -> [Header]
forall a. Eq a => [a] -> [a]
nub [Header]
headers ]
                      fun_proto :: SDoc
fun_proto = SDoc
constQual SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+> SDoc
cResType SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+> SDoc
pprCconv SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+> CLabelString -> SDoc
forall a. Outputable a => a -> SDoc
ppr CLabelString
wrapperName SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
parens SDoc
argTypes
                      cRet :: SDoc
cRet
                       | Bool
isVoidRes =                   SDoc
cCall
                       | Bool
otherwise = String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"return" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+> SDoc
cCall
                      cCall :: SDoc
cCall
                        | Bool
isFun = CLabelString -> SDoc
forall a. Outputable a => a -> SDoc
ppr CLabelString
cName SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
parens SDoc
argVals
                        | [Scaled Type] -> Bool
forall a. [a] -> Bool
forall (t :: * -> *) a. Foldable t => t a -> Bool
null [Scaled Type]
arg_tys = CLabelString -> SDoc
forall a. Outputable a => a -> SDoc
ppr CLabelString
cName
                        | Bool
otherwise = String -> SDoc
forall a. HasCallStack => String -> a
panic String
"dsFCall: Unexpected arguments to FFI value import"
                      raw_res_ty :: Type
raw_res_ty = case Type -> Maybe (TyCon, Type)
tcSplitIOType_maybe Type
io_res_ty of
                                   Just (TyCon
_ioTyCon, Type
res_ty) -> Type
res_ty
                                   Maybe (TyCon, Type)
Nothing                 -> Type
io_res_ty
                      isVoidRes :: Bool
isVoidRes = Type
raw_res_ty Type -> Type -> Bool
`eqType` Type
unitTy
                      (Maybe Header
mHeader, SDoc
cResType)
                       | Bool
isVoidRes = (Maybe Header
forall a. Maybe a
Nothing, String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"void")
                       | Bool
otherwise = Type -> (Maybe Header, SDoc)
toCType Type
raw_res_ty
                      pprCconv :: SDoc
pprCconv = CCallConv -> SDoc
ccallConvAttribute CCallConv
CApiConv
                      mHeadersArgTypeList :: [(Maybe Header, SDoc)]
mHeadersArgTypeList
                          = [ (Maybe Header
header, SDoc
cType SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+> Char -> SDoc
forall doc. IsLine doc => Char -> doc
char Char
'a' SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> Int -> SDoc
forall doc. IsLine doc => Int -> doc
int Int
n)
                            | (Scaled Type
t, Int
n) <- [Scaled Type] -> [Int] -> [(Scaled Type, Int)]
forall a b. [a] -> [b] -> [(a, b)]
zip [Scaled Type]
arg_tys [Int
1..]
                            , let (Maybe Header
header, SDoc
cType) = Type -> (Maybe Header, SDoc)
toCType (Scaled Type -> Type
forall a. Scaled a -> a
scaledThing Scaled Type
t) ]
                      ([Maybe Header]
mHeaders, [SDoc]
argTypeList) = [(Maybe Header, SDoc)] -> ([Maybe Header], [SDoc])
forall a b. [(a, b)] -> ([a], [b])
unzip [(Maybe Header, SDoc)]
mHeadersArgTypeList
                      argTypes :: SDoc
argTypes = if [SDoc] -> Bool
forall a. [a] -> Bool
forall (t :: * -> *) a. Foldable t => t a -> Bool
null [SDoc]
argTypeList
                                 then String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"void"
                                 else [SDoc] -> SDoc
forall doc. IsLine doc => [doc] -> doc
hsep ([SDoc] -> SDoc) -> [SDoc] -> SDoc
forall a b. (a -> b) -> a -> b
$ SDoc -> [SDoc] -> [SDoc]
forall doc. IsLine doc => doc -> [doc] -> [doc]
punctuate SDoc
forall doc. IsLine doc => doc
comma [SDoc]
argTypeList
                      mHeaders' :: [Maybe Header]
mHeaders' = Maybe Header
mDeclHeader Maybe Header -> [Maybe Header] -> [Maybe Header]
forall a. a -> [a] -> [a]
: Maybe Header
mHeader Maybe Header -> [Maybe Header] -> [Maybe Header]
forall a. a -> [a] -> [a]
: [Maybe Header]
mHeaders
                      headers :: [Header]
headers = [Maybe Header] -> [Header]
forall a. [Maybe a] -> [a]
catMaybes [Maybe Header]
mHeaders'
                      argVals :: SDoc
argVals = [SDoc] -> SDoc
forall doc. IsLine doc => [doc] -> doc
hsep ([SDoc] -> SDoc) -> [SDoc] -> SDoc
forall a b. (a -> b) -> a -> b
$ SDoc -> [SDoc] -> [SDoc]
forall doc. IsLine doc => doc -> [doc] -> [doc]
punctuate SDoc
forall doc. IsLine doc => doc
comma
                                    [ Char -> SDoc
forall doc. IsLine doc => Char -> doc
char Char
'a' SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> Int -> SDoc
forall doc. IsLine doc => Int -> doc
int Int
n
                                    | (Scaled Type
_, Int
n) <- [Scaled Type] -> [Int] -> [(Scaled Type, Int)]
forall a b. [a] -> [b] -> [(a, b)]
zip [Scaled Type]
arg_tys [Int
1..] ]
                  (ForeignCall, SDoc)
-> IOEnv (Env DsGblEnv DsLclEnv) (ForeignCall, SDoc)
forall a. a -> IOEnv (Env DsGblEnv DsLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return (ForeignCall
fcall', SDoc
c)
              ForeignCall
_ ->
                  (ForeignCall, SDoc)
-> IOEnv (Env DsGblEnv DsLclEnv) (ForeignCall, SDoc)
forall a. a -> IOEnv (Env DsGblEnv DsLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return (ForeignCall
fcall, SDoc
forall doc. IsOutput doc => doc
empty)
    DynFlags
dflags <- IOEnv (Env DsGblEnv DsLclEnv) DynFlags
forall (m :: * -> *). HasDynFlags m => m DynFlags
getDynFlags
    let
        -- Build the worker
        worker_ty :: Type
worker_ty     = [TyVarBinder] -> Type -> Type
mkForAllTys [TyVarBinder]
tv_bndrs ([Type] -> Type -> Type
mkVisFunTysMany ((Id -> Type) -> [Id] -> [Type]
forall a b. (a -> b) -> [a] -> [b]
map Id -> Type
idType [Id]
work_arg_ids) Type
ccall_result_ty)
        tvs :: [Id]
tvs           = (TyVarBinder -> Id) -> [TyVarBinder] -> [Id]
forall a b. (a -> b) -> [a] -> [b]
map TyVarBinder -> Id
forall tv argf. VarBndr tv argf -> tv
binderVar [TyVarBinder]
tv_bndrs
        the_ccall_app :: CoreExpr
the_ccall_app = Unique -> ForeignCall -> [CoreExpr] -> Type -> CoreExpr
mkFCall Unique
ccall_uniq ForeignCall
fcall' [CoreExpr]
val_args Type
ccall_result_ty
        work_rhs :: CoreExpr
work_rhs      = [Id] -> CoreExpr -> CoreExpr
forall b. [b] -> Expr b -> Expr b
mkLams [Id]
tvs ([Id] -> CoreExpr -> CoreExpr
forall b. [b] -> Expr b -> Expr b
mkLams [Id]
work_arg_ids CoreExpr
the_ccall_app)
        work_id :: Id
work_id       = CLabelString -> Unique -> Type -> Type -> Id
mkSysLocal (String -> CLabelString
fsLit String
"$wccall") Unique
work_uniq Type
ManyTy Type
worker_ty

        -- Build the wrapper
        work_app :: CoreExpr
work_app     = CoreExpr -> [CoreExpr] -> CoreExpr
forall b. Expr b -> [Expr b] -> Expr b
mkApps (CoreExpr -> [Id] -> CoreExpr
forall b. Expr b -> [Id] -> Expr b
mkVarApps (Id -> CoreExpr
forall b. Id -> Expr b
Var Id
work_id) [Id]
tvs) [CoreExpr]
val_args
        wrapper_body :: CoreExpr
wrapper_body = ((CoreExpr -> CoreExpr) -> CoreExpr -> CoreExpr)
-> CoreExpr -> [CoreExpr -> CoreExpr] -> CoreExpr
forall a b. (a -> b -> b) -> b -> [a] -> b
forall (t :: * -> *) a b.
Foldable t =>
(a -> b -> b) -> b -> t a -> b
foldr (CoreExpr -> CoreExpr) -> CoreExpr -> CoreExpr
forall a b. (a -> b) -> a -> b
($) (CoreExpr -> CoreExpr
res_wrapper CoreExpr
work_app) [CoreExpr -> CoreExpr]
arg_wrappers
        wrap_rhs :: CoreExpr
wrap_rhs     = [Id] -> CoreExpr -> CoreExpr
forall b. [b] -> Expr b -> Expr b
mkLams ([Id]
tvs [Id] -> [Id] -> [Id]
forall a. [a] -> [a] -> [a]
++ [Id]
args) CoreExpr
wrapper_body
        wrap_rhs' :: CoreExpr
wrap_rhs'    = CoreExpr -> Coercion -> CoreExpr
forall b. Expr b -> Coercion -> Expr b
Cast CoreExpr
wrap_rhs Coercion
co
        simpl_opts :: SimpleOpts
simpl_opts   = DynFlags -> SimpleOpts
initSimpleOpts DynFlags
dflags
        fn_id_w_inl :: Id
fn_id_w_inl  = Id
fn_id Id -> Unfolding -> Id
`setIdUnfolding` SimpleOpts -> UnfoldingSource -> Int -> CoreExpr -> Unfolding
mkInlineUnfoldingWithArity SimpleOpts
simpl_opts
                                                UnfoldingSource
StableSystemSrc ([Id] -> Int
forall a. [a] -> Int
forall (t :: * -> *) a. Foldable t => t a -> Int
length [Id]
args)
                                                CoreExpr
wrap_rhs'

    ([Binding], CHeader, CStub) -> DsM ([Binding], CHeader, CStub)
forall a. a -> IOEnv (Env DsGblEnv DsLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return ([(Id
work_id, CoreExpr
work_rhs), (Id
fn_id_w_inl, CoreExpr
wrap_rhs')], CHeader
forall a. Monoid a => a
mempty, SDoc -> [CLabel] -> [CLabel] -> CStub
CStub SDoc
cDoc [] [])


toCName :: Id -> String
toCName :: Id -> String
toCName Id
i = SDocContext -> SDoc -> String
showSDocOneLine SDocContext
defaultSDocContext (SDoc -> SDoc
pprCode (Name -> SDoc
forall a. Outputable a => a -> SDoc
ppr (Id -> Name
idName Id
i)))

toCType :: Type -> (Maybe Header, SDoc)
toCType :: Type -> (Maybe Header, SDoc)
toCType = Bool -> Type -> (Maybe Header, SDoc)
forall {b}. IsLine b => Bool -> Type -> (Maybe Header, b)
f Bool
False
    where f :: Bool -> Type -> (Maybe Header, b)
f Bool
voidOK Type
t
           -- First, if we have (Ptr t) of (FunPtr t), then we need to
           -- convert t to a C type and put a * after it. If we don't
           -- know a type for t, then "void" is fine, though.
           | Just (TyCon
ptr, [Type
t']) <- HasDebugCallStack => Type -> Maybe (TyCon, [Type])
Type -> Maybe (TyCon, [Type])
splitTyConApp_maybe Type
t
           , TyCon -> Name
tyConName TyCon
ptr Name -> [Name] -> Bool
forall a. Eq a => a -> [a] -> Bool
forall (t :: * -> *) a. (Foldable t, Eq a) => a -> t a -> Bool
`elem` [Name
ptrTyConName, Name
funPtrTyConName]
              = case Bool -> Type -> (Maybe Header, b)
f Bool
True Type
t' of
                (Maybe Header
mh, b
cType') ->
                    (Maybe Header
mh, b
cType' b -> b -> b
forall doc. IsLine doc => doc -> doc -> doc
<> Char -> b
forall doc. IsLine doc => Char -> doc
char Char
'*')
           -- Otherwise, if we have a type constructor application, then
           -- see if there is a C type associated with that constructor.
           -- Note that we aren't looking through type synonyms or
           -- anything, as it may be the synonym that is annotated.
           | Just TyCon
tycon <- Type -> Maybe TyCon
tyConAppTyConPicky_maybe Type
t
           , Just (CType SourceText
_ Maybe Header
mHeader (SourceText
_,CLabelString
cType)) <- TyCon -> Maybe CType
tyConCType_maybe TyCon
tycon
              = (Maybe Header
mHeader, CLabelString -> b
forall doc. IsLine doc => CLabelString -> doc
ftext CLabelString
cType)
           -- If we don't know a C type for this type, then try looking
           -- through one layer of type synonym etc.
           | Just Type
t' <- Type -> Maybe Type
coreView Type
t
              = Bool -> Type -> (Maybe Header, b)
f Bool
voidOK Type
t'
          -- Handle 'UnliftedFFITypes' argument
           | Just TyCon
tyCon <- Type -> Maybe TyCon
tyConAppTyConPicky_maybe Type
t
           , TyCon -> Bool
isPrimTyCon TyCon
tyCon
           , Just String
cType <- TyCon -> Maybe String
ppPrimTyConStgType TyCon
tyCon
           = (Maybe Header
forall a. Maybe a
Nothing, String -> b
forall doc. IsLine doc => String -> doc
text String
cType)

           -- Otherwise we don't know the C type. If we are allowing
           -- void then return that; otherwise something has gone wrong.
           | Bool
voidOK = (Maybe Header
forall a. Maybe a
Nothing, String -> b
forall doc. IsLine doc => String -> doc
text String
"void")
           | Bool
otherwise
              = String -> SDoc -> (Maybe Header, b)
forall a. HasCallStack => String -> SDoc -> a
pprPanic String
"toCType" (Type -> SDoc
forall a. Outputable a => a -> SDoc
ppr Type
t)

{-
*

\subsection{Generating @foreign export@ stubs}

*

For each @foreign export@ function, a C stub function is generated.
The C stub constructs the application of the exported Haskell function
using the hugs/ghc rts invocation API.
-}

mkFExportCBits :: DynFlags
               -> FastString
               -> Maybe Id      -- Just==static, Nothing==dynamic
               -> [Type]
               -> Type
               -> Bool          -- True <=> returns an IO type
               -> CCallConv
               -> (CHeader,
                   CStub,
                   String,      -- the argument reps
                   Int          -- total size of arguments
                  )
mkFExportCBits :: DynFlags
-> CLabelString
-> Maybe Id
-> [Type]
-> Type
-> Bool
-> CCallConv
-> (CHeader, CStub, String, Int)
mkFExportCBits DynFlags
dflags CLabelString
c_nm Maybe Id
maybe_target [Type]
arg_htys Type
res_hty Bool
is_IO_res_ty CCallConv
cc
 =
   ( CHeader
header_bits
   , SDoc -> [CLabel] -> [CLabel] -> CStub
CStub SDoc
body [] []
   , String
type_string,
    Int
aug_arg_size
    )
 where
  platform :: Platform
platform = DynFlags -> Platform
targetPlatform DynFlags
dflags

  -- list the arguments to the C function
  arg_info :: [(SDoc,           -- arg name
                SDoc,           -- C type
                Type,           -- Haskell type
                CmmType)]       -- the CmmType
  arg_info :: [(SDoc, SDoc, Type, CmmType)]
arg_info  = [ let stg_type :: SDoc
stg_type = Type -> SDoc
showStgType Type
ty in
                (Int -> SDoc -> SDoc
arg_cname Int
n SDoc
stg_type,
                 SDoc
stg_type,
                 Type
ty,
                Platform -> Type -> CmmType
typeCmmType Platform
platform (Type -> Type
getPrimTyOf Type
ty))
              | (Type
ty,Int
n) <- [Type] -> [Int] -> [(Type, Int)]
forall a b. [a] -> [b] -> [(a, b)]
zip [Type]
arg_htys [Int
1::Int ..] ]

  arg_cname :: Int -> SDoc -> SDoc
arg_cname Int
n SDoc
stg_ty
        | Bool
libffi    = Char -> SDoc
forall doc. IsLine doc => Char -> doc
char Char
'*' SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
parens (SDoc
stg_ty SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> Char -> SDoc
forall doc. IsLine doc => Char -> doc
char Char
'*') SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<>
                      String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"args" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
brackets (Int -> SDoc
forall doc. IsLine doc => Int -> doc
int (Int
nInt -> Int -> Int
forall a. Num a => a -> a -> a
-Int
1))
        | Bool
otherwise = Char -> SDoc
forall doc. IsLine doc => Char -> doc
char Char
'a' SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> Int -> SDoc
forall doc. IsLine doc => Int -> doc
int Int
n

  -- generate a libffi-style stub if this is a "wrapper" and libffi is enabled
  libffi :: Bool
libffi = PlatformMisc -> Bool
platformMisc_libFFI (DynFlags -> PlatformMisc
platformMisc DynFlags
dflags) Bool -> Bool -> Bool
&& Maybe Id -> Bool
forall a. Maybe a -> Bool
isNothing Maybe Id
maybe_target

  type_string :: String
type_string
      -- libffi needs to know the result type too:
      | Bool
libffi    = Platform -> Type -> Char
primTyDescChar Platform
platform Type
res_hty Char -> String -> String
forall a. a -> [a] -> [a]
: String
arg_type_string
      | Bool
otherwise = String
arg_type_string

  arg_type_string :: String
arg_type_string = [Platform -> Type -> Char
primTyDescChar Platform
platform Type
ty | (SDoc
_,SDoc
_,Type
ty,CmmType
_) <- [(SDoc, SDoc, Type, CmmType)]
arg_info]
                -- just the real args

  -- 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 :: [(SDoc, SDoc, Type, CmmType)]
aug_arg_info
    | Maybe Id -> Bool
forall a. Maybe a -> Bool
isNothing Maybe Id
maybe_target = (SDoc, SDoc, Type, CmmType)
stable_ptr_arg (SDoc, SDoc, Type, CmmType)
-> [(SDoc, SDoc, Type, CmmType)] -> [(SDoc, SDoc, Type, CmmType)]
forall a. a -> [a] -> [a]
: Platform
-> CCallConv
-> [(SDoc, SDoc, Type, CmmType)]
-> [(SDoc, SDoc, Type, CmmType)]
insertRetAddr Platform
platform CCallConv
cc [(SDoc, SDoc, Type, CmmType)]
arg_info
    | Bool
otherwise              = [(SDoc, SDoc, Type, CmmType)]
arg_info

  aug_arg_size :: Int
aug_arg_size = [Int] -> Int
forall a. Num a => [a] -> a
forall (t :: * -> *) a. (Foldable t, Num a) => t a -> a
sum [ Width -> Int
widthInBytes (CmmType -> Width
typeWidth CmmType
rep) | (SDoc
_,SDoc
_,Type
_,CmmType
rep) <- [(SDoc, SDoc, Type, CmmType)]
aug_arg_info]
         -- 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
         -- AK: This seems just wrong, the code here uses widthInBytes, but when
         -- we pass args on the haskell stack we always extend to multiples of 8
         -- to my knowledge. Not sure if it matters though so I won't touch this
         -- for now.

  stable_ptr_arg :: (SDoc, SDoc, Type, CmmType)
stable_ptr_arg =
        (String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"the_stableptr", String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"StgStablePtr", Type
forall a. HasCallStack => a
undefined,
         Platform -> Type -> CmmType
typeCmmType Platform
platform (Type -> Type
mkStablePtrPrimTy Type
alphaTy))

  -- stuff to do with the return type of the C function
  res_hty_is_unit :: Bool
res_hty_is_unit = Type
res_hty Type -> Type -> Bool
`eqType` Type
unitTy     -- Look through any newtypes

  cResType :: SDoc
cResType | Bool
res_hty_is_unit = String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"void"
           | Bool
otherwise       = Type -> SDoc
showStgType Type
res_hty

  -- when the return type is integral and word-sized or smaller, it
  -- must be assigned as type ffi_arg (#3516).  To see what type
  -- libffi is expecting here, take a look in its own testsuite, e.g.
  -- libffi/testsuite/libffi.call/cls_align_ulonglong.c
  ffi_cResType :: SDoc
ffi_cResType
     | Bool
is_ffi_arg_type = String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"ffi_arg"
     | Bool
otherwise       = SDoc
cResType
     where
       res_ty_key :: Unique
res_ty_key = Name -> Unique
forall a. Uniquable a => a -> Unique
getUnique (TyCon -> Name
forall a. NamedThing a => a -> Name
getName (Type -> TyCon
typeTyCon Type
res_hty))
       is_ffi_arg_type :: Bool
is_ffi_arg_type = Unique
res_ty_key Unique -> [Unique] -> Bool
forall (t :: * -> *) a. (Foldable t, Eq a) => a -> t a -> Bool
`notElem`
              [Unique
floatTyConKey, Unique
doubleTyConKey,
               Unique
int64TyConKey, Unique
word64TyConKey]

  -- Now we can cook up the prototype for the exported function.
  pprCconv :: SDoc
pprCconv = CCallConv -> SDoc
ccallConvAttribute CCallConv
cc

  header_bits :: CHeader
header_bits = SDoc -> CHeader
CHeader (String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"extern" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+> SDoc
fun_proto SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc
forall doc. IsLine doc => doc
semi)

  fun_args :: SDoc
fun_args
    | [(SDoc, SDoc, Type, CmmType)] -> Bool
forall a. [a] -> Bool
forall (t :: * -> *) a. Foldable t => t a -> Bool
null [(SDoc, SDoc, Type, CmmType)]
aug_arg_info = String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"void"
    | Bool
otherwise         = [SDoc] -> SDoc
forall doc. IsLine doc => [doc] -> doc
hsep ([SDoc] -> SDoc) -> [SDoc] -> SDoc
forall a b. (a -> b) -> a -> b
$ SDoc -> [SDoc] -> [SDoc]
forall doc. IsLine doc => doc -> [doc] -> [doc]
punctuate SDoc
forall doc. IsLine doc => doc
comma
                               ([SDoc] -> [SDoc]) -> [SDoc] -> [SDoc]
forall a b. (a -> b) -> a -> b
$ ((SDoc, SDoc, Type, CmmType) -> SDoc)
-> [(SDoc, SDoc, Type, CmmType)] -> [SDoc]
forall a b. (a -> b) -> [a] -> [b]
map (\(SDoc
nm,SDoc
ty,Type
_,CmmType
_) -> SDoc
ty SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+> SDoc
nm) [(SDoc, SDoc, Type, CmmType)]
aug_arg_info

  fun_proto :: SDoc
fun_proto
    | Bool
libffi
      = String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"void" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+> CLabelString -> SDoc
forall doc. IsLine doc => CLabelString -> doc
ftext CLabelString
c_nm SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<>
          SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
parens (String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"void *cif STG_UNUSED, void* resp, void** args, void* the_stableptr")
    | Bool
otherwise
      = SDoc
cResType SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+> SDoc
pprCconv SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+> CLabelString -> SDoc
forall doc. IsLine doc => CLabelString -> doc
ftext CLabelString
c_nm SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
parens SDoc
fun_args

  -- the target which will form the root of what we ask rts_inCall to run
  the_cfun :: SDoc
the_cfun
     = case Maybe Id
maybe_target of
          Maybe Id
Nothing    -> String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"(StgClosure*)deRefStablePtr(the_stableptr)"
          Just Id
hs_fn -> Char -> SDoc
forall doc. IsLine doc => Char -> doc
char Char
'&' SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> Id -> SDoc
forall a. Outputable a => a -> SDoc
ppr Id
hs_fn SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"_closure"

  cap :: SDoc
cap = String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"cap" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc
forall doc. IsLine doc => doc
comma

  -- the expression we give to rts_inCall
  expr_to_run :: SDoc
expr_to_run
     = (SDoc -> (SDoc, SDoc, Type, CmmType) -> SDoc)
-> SDoc -> [(SDoc, SDoc, Type, CmmType)] -> SDoc
forall b a. (b -> a -> b) -> b -> [a] -> b
forall (t :: * -> *) b a.
Foldable t =>
(b -> a -> b) -> b -> t a -> b
foldl' SDoc -> (SDoc, SDoc, Type, CmmType) -> SDoc
appArg SDoc
the_cfun [(SDoc, SDoc, Type, CmmType)]
arg_info -- NOT aug_arg_info
       where
          appArg :: SDoc -> (SDoc, SDoc, Type, CmmType) -> SDoc
appArg SDoc
acc (SDoc
arg_cname, SDoc
_, Type
arg_hty, CmmType
_)
             = String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"rts_apply"
               SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
parens (SDoc
cap SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc
acc SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc
forall doc. IsLine doc => doc
comma SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> Type -> SDoc
mkHObj Type
arg_hty SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
parens (SDoc
cap SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc
arg_cname))

  -- various other bits for inside the fn
  declareResult :: SDoc
declareResult = String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"HaskellObj ret;"
  declareCResult :: SDoc
declareCResult | Bool
res_hty_is_unit = SDoc
forall doc. IsOutput doc => doc
empty
                 | Bool
otherwise       = SDoc
cResType SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+> String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"cret;"

  assignCResult :: SDoc
assignCResult | Bool
res_hty_is_unit = SDoc
forall doc. IsOutput doc => doc
empty
                | Bool
otherwise       =
                        String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"cret=" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> Type -> SDoc
unpackHObj Type
res_hty SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
parens (String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"ret") SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc
forall doc. IsLine doc => doc
semi

  -- an extern decl for the fn being called
  extern_decl :: SDoc
extern_decl
     = case Maybe Id
maybe_target of
          Maybe Id
Nothing -> SDoc
forall doc. IsOutput doc => doc
empty
          Just Id
hs_fn -> String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"extern StgClosure " SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> Id -> SDoc
forall a. Outputable a => a -> SDoc
ppr Id
hs_fn SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"_closure" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc
forall doc. IsLine doc => doc
semi


  -- finally, the whole darn thing
  body :: SDoc
body =
    SDoc
forall doc. IsLine doc => doc
space SDoc -> SDoc -> SDoc
forall doc. IsDoc doc => doc -> doc -> doc
$$
    SDoc
extern_decl SDoc -> SDoc -> SDoc
forall doc. IsDoc doc => doc -> doc -> doc
$$
    SDoc
fun_proto  SDoc -> SDoc -> SDoc
forall doc. IsDoc doc => doc -> doc -> doc
$$
    [SDoc] -> SDoc
forall doc. IsDoc doc => [doc] -> doc
vcat
     [ SDoc
forall doc. IsLine doc => doc
lbrace
     ,   String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"Capability *cap;"
     ,   SDoc
declareResult
     ,   SDoc
declareCResult
     ,   String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"cap = rts_lock();"
          -- create the application + perform it.
     ,   String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"rts_inCall" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
parens (
                Char -> SDoc
forall doc. IsLine doc => Char -> doc
char Char
'&' SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc
cap SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<>
                String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"rts_apply" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
parens (
                    SDoc
cap SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<>
                    String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"(HaskellObj)"
                 SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> (if Bool
is_IO_res_ty
                      then String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"runIO_closure"
                      else String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"runNonIO_closure")
                 SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc
forall doc. IsLine doc => doc
comma
                 SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc
expr_to_run
                ) SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+> SDoc
forall doc. IsLine doc => doc
comma
               SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"&ret"
             ) SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc
forall doc. IsLine doc => doc
semi
     ,   String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"rts_checkSchedStatus" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
parens (SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
doubleQuotes (CLabelString -> SDoc
forall doc. IsLine doc => CLabelString -> doc
ftext CLabelString
c_nm)
                                                SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc
forall doc. IsLine doc => doc
comma SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"cap") SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc
forall doc. IsLine doc => doc
semi
     ,   SDoc
assignCResult
     ,   String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"rts_unlock(cap);"
     ,   Bool -> SDoc -> SDoc
forall doc. IsOutput doc => Bool -> doc -> doc
ppUnless Bool
res_hty_is_unit (SDoc -> SDoc) -> SDoc -> SDoc
forall a b. (a -> b) -> a -> b
$
         if Bool
libffi
                  then Char -> SDoc
forall doc. IsLine doc => Char -> doc
char Char
'*' SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
parens (SDoc
ffi_cResType SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> Char -> SDoc
forall doc. IsLine doc => Char -> doc
char Char
'*') SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<>
                       String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"resp = " SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
parens SDoc
ffi_cResType SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"cret;"
                  else String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"return cret;"
     , SDoc
forall doc. IsLine doc => doc
rbrace
     ]

mkHObj :: Type -> SDoc
mkHObj :: Type -> SDoc
mkHObj Type
t = String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"rts_mk" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> Type -> SDoc
showFFIType Type
t

unpackHObj :: Type -> SDoc
unpackHObj :: Type -> SDoc
unpackHObj Type
t = String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"rts_get" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> Type -> SDoc
showFFIType Type
t

showStgType :: Type -> SDoc
showStgType :: Type -> SDoc
showStgType Type
t = String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"Hs" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<> Type -> SDoc
showFFIType Type
t

showFFIType :: Type -> SDoc
showFFIType :: Type -> SDoc
showFFIType Type
t = CLabelString -> SDoc
forall doc. IsLine doc => CLabelString -> doc
ftext (OccName -> CLabelString
occNameFS (TyCon -> OccName
forall a. NamedThing a => a -> OccName
getOccName (Type -> TyCon
typeTyCon Type
t)))

typeTyCon :: Type -> TyCon
typeTyCon :: Type -> TyCon
typeTyCon Type
ty
  | Just (TyCon
tc, [Type]
_) <- HasDebugCallStack => Type -> Maybe (TyCon, [Type])
Type -> Maybe (TyCon, [Type])
tcSplitTyConApp_maybe (Type -> Type
unwrapType Type
ty)
  = TyCon
tc
  | Bool
otherwise
  = String -> SDoc -> TyCon
forall a. HasCallStack => String -> SDoc -> a
pprPanic String
"GHC.HsToCore.Foreign.C.typeTyCon" (Type -> SDoc
forall a. Outputable a => a -> SDoc
ppr Type
ty)


insertRetAddr :: Platform -> CCallConv
              -> [(SDoc, SDoc, Type, CmmType)]
              -> [(SDoc, SDoc, Type, CmmType)]
insertRetAddr :: Platform
-> CCallConv
-> [(SDoc, SDoc, Type, CmmType)]
-> [(SDoc, SDoc, Type, CmmType)]
insertRetAddr Platform
platform CCallConv
CCallConv [(SDoc, SDoc, Type, CmmType)]
args
    = case Platform -> Arch
platformArch Platform
platform of
      Arch
ArchX86_64
       | Platform -> OS
platformOS Platform
platform OS -> OS -> Bool
forall a. Eq a => a -> a -> Bool
== OS
OSMinGW32 ->
          -- On other Windows x86_64 we insert the return address
          -- after the 4th argument, because this is the point
          -- at which we need to flush a register argument to the stack
          -- (See rts/Adjustor.c for details).
          let go :: Int -> [(SDoc, SDoc, Type, CmmType)]
                        -> [(SDoc, SDoc, Type, CmmType)]
              go :: Int
-> [(SDoc, SDoc, Type, CmmType)] -> [(SDoc, SDoc, Type, CmmType)]
go Int
4 [(SDoc, SDoc, Type, CmmType)]
args = Platform -> (SDoc, SDoc, Type, CmmType)
ret_addr_arg Platform
platform (SDoc, SDoc, Type, CmmType)
-> [(SDoc, SDoc, Type, CmmType)] -> [(SDoc, SDoc, Type, CmmType)]
forall a. a -> [a] -> [a]
: [(SDoc, SDoc, Type, CmmType)]
args
              go Int
n ((SDoc, SDoc, Type, CmmType)
arg:[(SDoc, SDoc, Type, CmmType)]
args) = (SDoc, SDoc, Type, CmmType)
arg (SDoc, SDoc, Type, CmmType)
-> [(SDoc, SDoc, Type, CmmType)] -> [(SDoc, SDoc, Type, CmmType)]
forall a. a -> [a] -> [a]
: Int
-> [(SDoc, SDoc, Type, CmmType)] -> [(SDoc, SDoc, Type, CmmType)]
go (Int
nInt -> Int -> Int
forall a. Num a => a -> a -> a
+Int
1) [(SDoc, SDoc, Type, CmmType)]
args
              go Int
_ [] = []
          in Int
-> [(SDoc, SDoc, Type, CmmType)] -> [(SDoc, SDoc, Type, CmmType)]
go Int
0 [(SDoc, SDoc, Type, CmmType)]
args
       | Bool
otherwise ->
          -- On other x86_64 platforms 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).
          let go :: Int -> [(SDoc, SDoc, Type, CmmType)]
                        -> [(SDoc, SDoc, Type, CmmType)]
              go :: Int
-> [(SDoc, SDoc, Type, CmmType)] -> [(SDoc, SDoc, Type, CmmType)]
go Int
6 [(SDoc, SDoc, Type, CmmType)]
args = Platform -> (SDoc, SDoc, Type, CmmType)
ret_addr_arg Platform
platform (SDoc, SDoc, Type, CmmType)
-> [(SDoc, SDoc, Type, CmmType)] -> [(SDoc, SDoc, Type, CmmType)]
forall a. a -> [a] -> [a]
: [(SDoc, SDoc, Type, CmmType)]
args
              go Int
n (arg :: (SDoc, SDoc, Type, CmmType)
arg@(SDoc
_,SDoc
_,Type
_,CmmType
rep):[(SDoc, SDoc, Type, CmmType)]
args)
                -- Int type fitting into int register
                | (CmmType -> Bool
isBitsType CmmType
rep Bool -> Bool -> Bool
&& CmmType -> Width
typeWidth CmmType
rep Width -> Width -> Bool
forall a. Ord a => a -> a -> Bool
<= Width
W64 Bool -> Bool -> Bool
|| CmmType -> Bool
isGcPtrType CmmType
rep)
                = (SDoc, SDoc, Type, CmmType)
arg (SDoc, SDoc, Type, CmmType)
-> [(SDoc, SDoc, Type, CmmType)] -> [(SDoc, SDoc, Type, CmmType)]
forall a. a -> [a] -> [a]
: Int
-> [(SDoc, SDoc, Type, CmmType)] -> [(SDoc, SDoc, Type, CmmType)]
go (Int
nInt -> Int -> Int
forall a. Num a => a -> a -> a
+Int
1) [(SDoc, SDoc, Type, CmmType)]
args
                | Bool
otherwise
                = (SDoc, SDoc, Type, CmmType)
arg (SDoc, SDoc, Type, CmmType)
-> [(SDoc, SDoc, Type, CmmType)] -> [(SDoc, SDoc, Type, CmmType)]
forall a. a -> [a] -> [a]
: Int
-> [(SDoc, SDoc, Type, CmmType)] -> [(SDoc, SDoc, Type, CmmType)]
go Int
n [(SDoc, SDoc, Type, CmmType)]
args
              go Int
_ [] = []
          in Int
-> [(SDoc, SDoc, Type, CmmType)] -> [(SDoc, SDoc, Type, CmmType)]
go Int
0 [(SDoc, SDoc, Type, CmmType)]
args
      Arch
_ ->
          Platform -> (SDoc, SDoc, Type, CmmType)
ret_addr_arg Platform
platform (SDoc, SDoc, Type, CmmType)
-> [(SDoc, SDoc, Type, CmmType)] -> [(SDoc, SDoc, Type, CmmType)]
forall a. a -> [a] -> [a]
: [(SDoc, SDoc, Type, CmmType)]
args
insertRetAddr Platform
_ CCallConv
_ [(SDoc, SDoc, Type, CmmType)]
args = [(SDoc, SDoc, Type, CmmType)]
args

ret_addr_arg :: Platform -> (SDoc, SDoc, Type, CmmType)
ret_addr_arg :: Platform -> (SDoc, SDoc, Type, CmmType)
ret_addr_arg Platform
platform = (String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"original_return_addr", String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"void*", Type
forall a. HasCallStack => a
undefined,
                         Platform -> Type -> CmmType
typeCmmType Platform
platform Type
addrPrimTy)

-- For stdcall labels, if the type was a FunPtr or newtype thereof,
-- then we need to calculate the size of the arguments in order to add
-- the @n suffix to the label.
fun_type_arg_stdcall_info :: Platform -> CCallConv -> Type -> Maybe Int
fun_type_arg_stdcall_info :: Platform -> CCallConv -> Type -> Maybe Int
fun_type_arg_stdcall_info Platform
platform CCallConv
StdCallConv Type
ty
  | Just (TyCon
tc,[Type
arg_ty]) <- HasDebugCallStack => Type -> Maybe (TyCon, [Type])
Type -> Maybe (TyCon, [Type])
splitTyConApp_maybe Type
ty,
    TyCon -> Unique
tyConUnique TyCon
tc Unique -> Unique -> Bool
forall a. Eq a => a -> a -> Bool
== Unique
funPtrTyConKey
  = let
       ([PiTyVarBinder]
bndrs, Type
_) = Type -> ([PiTyVarBinder], Type)
tcSplitPiTys Type
arg_ty
       fe_arg_tys :: [Type]
fe_arg_tys = (PiTyVarBinder -> Maybe Type) -> [PiTyVarBinder] -> [Type]
forall a b. (a -> Maybe b) -> [a] -> [b]
mapMaybe PiTyVarBinder -> Maybe Type
anonPiTyBinderType_maybe [PiTyVarBinder]
bndrs
    in Int -> Maybe Int
forall a. a -> Maybe a
Just (Int -> Maybe Int) -> Int -> Maybe Int
forall a b. (a -> b) -> a -> b
$ [Int] -> Int
forall a. Num a => [a] -> a
forall (t :: * -> *) a. (Foldable t, Num a) => t a -> a
sum ((Type -> Int) -> [Type] -> [Int]
forall a b. (a -> b) -> [a] -> [b]
map (Width -> Int
widthInBytes (Width -> Int) -> (Type -> Width) -> Type -> Int
forall b c a. (b -> c) -> (a -> b) -> a -> c
. CmmType -> Width
typeWidth (CmmType -> Width) -> (Type -> CmmType) -> Type -> Width
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Platform -> Type -> CmmType
typeCmmType Platform
platform (Type -> CmmType) -> (Type -> Type) -> Type -> CmmType
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Type -> Type
getPrimTyOf) [Type]
fe_arg_tys)
fun_type_arg_stdcall_info Platform
_ CCallConv
_other_conv Type
_
  = Maybe Int
forall a. Maybe a
Nothing