\begin{code}
module DsCCall
( dsCCall
- , mkCCall
+ , mkFCall
, unboxArg
, boxResult
, resultWrapper
import CoreSyn
import DsMonad
-import DsUtils
import CoreUtils ( exprType, mkCoerce )
-import Id ( Id, mkWildId )
-import MkId ( mkCCallOpId, realWorldPrimId )
+import Id ( Id, mkWildId, idType )
+import MkId ( mkFCallId, realWorldPrimId, mkPrimOpId )
import Maybes ( maybeToBool )
-import PrelInfo ( packStringForCId )
-import PrimOp ( PrimOp(..), CCall(..), CCallTarget(..) )
-import DataCon ( DataCon, splitProductType_maybe, dataConSourceArity, dataConWrapId )
-import CallConv
+import ForeignCall ( ForeignCall(..), CCallSpec(..), CCallTarget(..), Safety, CCallConv(..) )
+import DataCon ( splitProductType_maybe, dataConSourceArity, dataConWrapId )
+import ForeignCall ( ForeignCall, CCallTarget(..) )
import Type ( isUnLiftedType, splitAlgTyConApp_maybe, mkFunTys,
- splitTyConApp_maybe, tyVarsOfType, mkForAllTys,
- isNewType, repType, isUnLiftedType, mkFunTy,
+ splitTyConApp_maybe, tyVarsOfType, mkForAllTys, isPrimitiveType,
+ isNewType, repType, isUnLiftedType, mkFunTy, mkTyConApp,
Type
)
-import TysPrim ( byteArrayPrimTy, realWorldStatePrimTy,
- byteArrayPrimTyCon, mutableByteArrayPrimTyCon, intPrimTy
+import PrimOp ( PrimOp(TouchOp) )
+import TysPrim ( realWorldStatePrimTy,
+ byteArrayPrimTyCon, mutableByteArrayPrimTyCon,
+ intPrimTy, foreignObjPrimTy
)
-import TysWiredIn ( unitDataConId, stringTy,
- unboxedPairDataCon,
- mkUnboxedTupleTy, unboxedTupleCon,
- boolTy, trueDataCon, falseDataCon, trueDataConId, falseDataConId,
- unitTy
+import TysWiredIn ( unitDataConId,
+ unboxedSingletonDataCon, unboxedPairDataCon,
+ unboxedSingletonTyCon, unboxedPairTyCon,
+ boolTy, trueDataCon, falseDataCon,
+ trueDataConId, falseDataConId, unitTy
)
import Literal ( mkMachInt )
import CStrings ( CLabelString )
-import Unique ( Unique, Uniquable(..), ioTyConKey )
+import PrelNames ( Unique, hasKey, ioTyConKey )
import VarSet ( varSetElems )
import Outputable
\end{code}
\begin{code}
dsCCall :: CLabelString -- C routine to invoke
-> [CoreExpr] -- Arguments (desugared)
- -> Bool -- True <=> might cause Haskell GC
+ -> Safety -- Safety of the call
-> Bool -- True <=> really a "_casm_"
-> Type -- Type of the result: IO t
-> DsM CoreExpr
dsCCall lbl args may_gc is_asm result_ty
= mapAndUnzipDs unboxArg args `thenDs` \ (unboxed_args, arg_wrappers) ->
- boxResult result_ty `thenDs` \ (ccall_result_ty, res_wrapper) ->
+ boxResult [] result_ty `thenDs` \ (ccall_result_ty, res_wrapper) ->
getUniqueDs `thenDs` \ uniq ->
let
- the_ccall = CCall (StaticTarget lbl) is_asm may_gc cCallConv
- the_prim_app = mkCCall uniq the_ccall unboxed_args ccall_result_ty
+ target | is_asm = CasmTarget lbl
+ | otherwise = StaticTarget lbl
+ the_fcall = CCall (CCallSpec target CCallConv may_gc)
+ the_prim_app = mkFCall uniq the_fcall unboxed_args ccall_result_ty
in
returnDs (foldr ($) (res_wrapper the_prim_app) arg_wrappers)
-mkCCall :: Unique -> CCall
+mkFCall :: Unique -> ForeignCall
-> [CoreExpr] -- Args
-> Type -- Result type
-> CoreExpr
-- Here we build a ccall thus
-- (ccallid::(forall a b. StablePtr (a -> b) -> Addr -> Char -> IO Addr))
-- a b s x c
-mkCCall uniq the_ccall val_args res_ty
- = mkApps (mkVarApps (Var the_ccall_id) tyvars) val_args
+mkFCall uniq the_fcall val_args res_ty
+ = mkApps (mkVarApps (Var the_fcall_id) tyvars) val_args
where
arg_tys = map exprType val_args
body_ty = (mkFunTys arg_tys res_ty)
tyvars = varSetElems (tyVarsOfType body_ty)
ty = mkForAllTys tyvars body_ty
- the_ccall_id = mkCCallOpId uniq the_ccall ty
+ the_fcall_id = mkFCallId uniq the_fcall ty
\end{code}
\begin{code}
-- where W is a CoreExpr that probably mentions x#
unboxArg arg
- -- Unlifted types: nothing to unbox
- | isUnLiftedType arg_ty
+ -- Primtive types: nothing to unbox
+ | isPrimitiveType arg_ty
= returnDs (arg, \body -> body)
-- Newtypes
= getSrcLocDs `thenDs` \ l ->
pprPanic "unboxArg: " (ppr l <+> ppr arg_ty)
where
- arg_ty = exprType arg
- arg_rep_ty = repType arg_ty
-
- maybe_product_type = splitProductType_maybe arg_ty
- is_product_type = maybeToBool maybe_product_type
- Just (tycon, _, data_con, data_con_arg_tys) = maybe_product_type
- data_con_arity = dataConSourceArity data_con
- (data_con_arg_ty1 : _) = data_con_arg_tys
+ arg_ty = exprType arg
+ maybe_product_type = splitProductType_maybe arg_ty
+ is_product_type = maybeToBool maybe_product_type
+ Just (_, _, data_con, data_con_arg_tys) = maybe_product_type
+ data_con_arity = dataConSourceArity data_con
+ (data_con_arg_ty1 : _) = data_con_arg_tys
(_ : _ : data_con_arg_ty3 : _) = data_con_arg_tys
maybe_arg3_tycon = splitTyConApp_maybe data_con_arg_ty3
\begin{code}
-boxResult :: Type -> DsM (Type, CoreExpr -> CoreExpr)
+boxResult :: [Id] -> Type -> DsM (Type, CoreExpr -> CoreExpr)
-- Takes the result of the user-level ccall:
-- either (IO t),
-- the result type will be
-- State# RealWorld -> (# State# RealWorld #)
-boxResult result_ty
+-- Here is where we arrange that ForeignPtrs which are passed to a 'safe'
+-- foreign import don't get finalized until the call returns. For each
+-- argument of type ForeignObj# we arrange to touch# the argument after
+-- the call. The arg_ids passed in are the Ids passed to the actual ccall.
+
+boxResult arg_ids result_ty
= case splitAlgTyConApp_maybe result_ty of
-- The result is IO t, so wrap the result in an IO constructor
- Just (io_tycon, [io_res_ty], [io_data_con]) | getUnique io_tycon == ioTyConKey
+ Just (io_tycon, [io_res_ty], [io_data_con]) | io_tycon `hasKey` ioTyConKey
-> mk_alt return_result
(resultWrapper io_res_ty) `thenDs` \ (ccall_res_ty, the_alt) ->
- newSysLocalDs realWorldStatePrimTy `thenDs` \ state_id ->
+ newSysLocalDs realWorldStatePrimTy `thenDs` \ state_id ->
let
- wrap = \ the_call -> mkApps (Var (dataConWrapId io_data_con))
- [Type io_res_ty, Lam state_id $
- Case (App the_call (Var state_id))
- (mkWildId ccall_res_ty)
- [the_alt]]
+ wrap = \ the_call ->
+ mkApps (Var (dataConWrapId io_data_con))
+ [ Type io_res_ty,
+ Lam state_id $
+ Case (App the_call (Var state_id))
+ (mkWildId ccall_res_ty)
+ [the_alt]
+ ]
in
returnDs (realWorldStatePrimTy `mkFunTy` ccall_res_ty, wrap)
where
-- It isn't, so do unsafePerformIO
-- It's not conveniently available, so we inline it
other -> mk_alt return_result
- (resultWrapper result_ty) `thenDs` \ (ccall_res_ty, the_alt) ->
+ (resultWrapper result_ty) `thenDs` \ (ccall_res_ty, the_alt) ->
let
wrap = \ the_call -> Case (App the_call (Var realWorldPrimId))
(mkWildId ccall_res_ty)
where
mk_alt return_result (Nothing, wrap_result)
= -- The ccall returns ()
+ let
+ rhs_fun state_id = return_result (Var state_id)
+ (wrap_result (panic "boxResult"))
+ in
newSysLocalDs realWorldStatePrimTy `thenDs` \ state_id ->
+ mkTouches arg_ids state_id rhs_fun `thenDs` \ the_rhs ->
let
- the_rhs = return_result (Var state_id) (wrap_result (panic "boxResult"))
- ccall_res_ty = mkUnboxedTupleTy 1 [realWorldStatePrimTy]
- the_alt = (DataAlt (unboxedTupleCon 1), [state_id], the_rhs)
+ ccall_res_ty = mkTyConApp unboxedSingletonTyCon [realWorldStatePrimTy]
+ the_alt = (DataAlt unboxedSingletonDataCon, [state_id], the_rhs)
in
returnDs (ccall_res_ty, the_alt)
mk_alt return_result (Just prim_res_ty, wrap_result)
= -- The ccall returns a non-() value
- newSysLocalDs realWorldStatePrimTy `thenDs` \ state_id ->
newSysLocalDs prim_res_ty `thenDs` \ result_id ->
let
- the_rhs = return_result (Var state_id) (wrap_result (Var result_id))
- ccall_res_ty = mkUnboxedTupleTy 2 [realWorldStatePrimTy, prim_res_ty]
+ rhs_fun state_id = return_result (Var state_id)
+ (wrap_result (Var result_id))
+ in
+ newSysLocalDs realWorldStatePrimTy `thenDs` \ state_id ->
+ mkTouches arg_ids state_id rhs_fun `thenDs` \ the_rhs ->
+ let
+ ccall_res_ty = mkTyConApp unboxedPairTyCon [realWorldStatePrimTy, prim_res_ty]
the_alt = (DataAlt unboxedPairDataCon, [state_id, result_id], the_rhs)
in
returnDs (ccall_res_ty, the_alt)
+touchzh = mkPrimOpId TouchOp
+
+mkTouches [] s cont = returnDs (cont s)
+mkTouches (v:vs) s cont
+ | idType v /= foreignObjPrimTy = mkTouches vs s cont
+ | otherwise = newSysLocalDs realWorldStatePrimTy `thenDs` \s' ->
+ mkTouches vs s' cont `thenDs` \ rest ->
+ returnDs (Case (mkApps (Var touchzh) [Type foreignObjPrimTy,
+ Var v, Var s]) s'
+ [(DEFAULT, [], rest)])
resultWrapper :: Type
-> (Maybe Type, -- Type of the expected result, if any
CoreExpr -> CoreExpr) -- Wrapper for the result
resultWrapper result_ty
-- Base case 1: primitive types
- | isUnLiftedType result_ty
+ | isPrimitiveType result_ty
= (Just result_ty, \e -> e)
-- Base case 1: the unit type ()
| otherwise
= pprPanic "resultWrapper" (ppr result_ty)
where
- maybe_product_type = splitProductType_maybe result_ty
- is_product_type = maybeToBool maybe_product_type
- Just (tycon, tycon_arg_tys, data_con, data_con_arg_tys) = maybe_product_type
- data_con_arity = dataConSourceArity data_con
+ maybe_product_type = splitProductType_maybe result_ty
+ is_product_type = maybeToBool maybe_product_type
+ Just (_, tycon_arg_tys, data_con, data_con_arg_tys) = maybe_product_type
+ data_con_arity = dataConSourceArity data_con
\end{code}