, mkCCall
, unboxArg
, boxResult
- , wrapUnboxedValue
- , can'tSeeDataConsPanic
-
+ , resultWrapper
) where
#include "HsVersions.h"
import DsMonad
import DsUtils
-import TcHsSyn ( maybeBoxedPrimType )
-import CoreUtils ( exprType )
+import CoreUtils ( exprType, mkCoerce )
import Id ( Id, mkWildId )
-import MkId ( mkCCallOpId )
+import MkId ( mkCCallOpId, realWorldPrimId )
import Maybes ( maybeToBool )
-import PrelInfo ( packStringForCId )
import PrimOp ( PrimOp(..), CCall(..), CCallTarget(..) )
-import DataCon ( DataCon, splitProductType_maybe )
+import DataCon ( DataCon, splitProductType_maybe, dataConSourceArity, dataConWrapId )
import CallConv
import Type ( isUnLiftedType, splitAlgTyConApp_maybe, mkFunTys,
- splitTyConApp_maybe, tyVarsOfType, mkForAllTys, Type
+ splitTyConApp_maybe, tyVarsOfType, mkForAllTys,
+ isNewType, repType, isUnLiftedType, mkFunTy,
+ Type
)
import TysPrim ( byteArrayPrimTy, realWorldStatePrimTy,
- byteArrayPrimTyCon, mutableByteArrayPrimTyCon )
+ byteArrayPrimTyCon, mutableByteArrayPrimTyCon, intPrimTy
+ )
import TysWiredIn ( unitDataConId, stringTy,
unboxedPairDataCon,
- mkUnboxedTupleTy, unboxedTupleCon
+ mkUnboxedTupleTy, unboxedTupleCon,
+ boolTy, trueDataCon, falseDataCon, trueDataConId, falseDataConId,
+ unitTy
)
-import Unique ( Unique )
+import Literal ( mkMachInt )
+import CStrings ( CLabelString )
+import Unique ( Unique, Uniquable(..), ioTyConKey )
import VarSet ( varSetElems )
import Outputable
\end{code}
\end{verbatim}
\begin{code}
-dsCCall :: FAST_STRING -- C routine to invoke
+dsCCall :: CLabelString -- C routine to invoke
-> [CoreExpr] -- Arguments (desugared)
-> Bool -- True <=> might cause Haskell GC
-> Bool -- True <=> really a "_casm_"
- -> Type -- Type of the result (a boxed-prim IO type)
+ -> Type -- Type of the result: IO t
-> DsM CoreExpr
dsCCall lbl args may_gc is_asm result_ty
- = newSysLocalDs realWorldStatePrimTy `thenDs` \ old_s ->
-
- mapAndUnzipDs unboxArg args `thenDs` \ (unboxed_args, arg_wrappers) ->
- boxResult result_ty `thenDs` \ (final_result_ty, res_wrapper) ->
+ = mapAndUnzipDs unboxArg args `thenDs` \ (unboxed_args, arg_wrappers) ->
+ boxResult result_ty `thenDs` \ (ccall_result_ty, res_wrapper) ->
getUniqueDs `thenDs` \ uniq ->
let
- val_args = Var old_s : unboxed_args
the_ccall = CCall (StaticTarget lbl) is_asm may_gc cCallConv
- the_prim_app = mkCCall uniq the_ccall val_args final_result_ty
- the_body = foldr ($) (res_wrapper the_prim_app) arg_wrappers
+ the_prim_app = mkCCall uniq the_ccall unboxed_args ccall_result_ty
in
- returnDs (Lam old_s the_body)
+ returnDs (foldr ($) (res_wrapper the_prim_app) arg_wrappers)
mkCCall :: Unique -> CCall
-> [CoreExpr] -- Args
-> DsM (CoreExpr, -- To pass as the actual argument
CoreExpr -> CoreExpr -- Wrapper to unbox the arg
)
-unboxArg arg
+-- Example: if the arg is e::Int, unboxArg will return
+-- (x#::Int#, \W. case x of I# x# -> W)
+-- where W is a CoreExpr that probably mentions x#
- -- Primitive types
- -- ADR Question: can this ever be used? None of the PrimTypes are
- -- instances of the CCallable class.
- --
- -- SOF response:
- -- Oh yes they are, I've just added them :-) Having _ccall_ and _casm_
- -- that accept unboxed arguments is a Good Thing if you have a stub generator
- -- which generates the boiler-plate box-unbox code for you, i.e., it may help
- -- us nuke this very module :-)
- --
+unboxArg arg
+ -- Unlifted types: nothing to unbox
| isUnLiftedType arg_ty
= returnDs (arg, \body -> body)
- -- Strings
- | arg_ty == stringTy
- -- ToDo (ADR): - allow synonyms of Strings too?
- = newSysLocalDs byteArrayPrimTy `thenDs` \ prim_arg ->
+ -- Newtypes
+ | isNewType arg_ty
+ = unboxArg (mkCoerce (repType arg_ty) arg_ty arg)
+
+ -- Booleans
+ | arg_ty == boolTy
+ = newSysLocalDs intPrimTy `thenDs` \ prim_arg ->
returnDs (Var prim_arg,
- \body -> Case (App (Var packStringForCId) arg)
- prim_arg [(DEFAULT,[],body)])
+ \ body -> Case (Case arg (mkWildId arg_ty)
+ [(DataAlt falseDataCon,[],mkIntLit 0),
+ (DataAlt trueDataCon, [],mkIntLit 1)])
+ prim_arg
+ [(DEFAULT,[],body)])
+
+ -- Data types with a single constructor, which has a single, primitive-typed arg
+ -- This deals with Int, Float etc
+ | is_product_type && data_con_arity == 1
+ = ASSERT(isUnLiftedType data_con_arg_ty1 ) -- Typechecker ensures this
+ newSysLocalDs arg_ty `thenDs` \ case_bndr ->
+ newSysLocalDs data_con_arg_ty1 `thenDs` \ prim_arg ->
+ returnDs (Var prim_arg,
+ \ body -> Case arg case_bndr [(DataAlt data_con,[prim_arg],body)]
+ )
-- Byte-arrays, both mutable and otherwise; hack warning
| is_product_type &&
- length data_con_arg_tys == 3 &&
+ data_con_arity == 3 &&
maybeToBool maybe_arg3_tycon &&
(arg3_tycon == byteArrayPrimTyCon ||
arg3_tycon == mutableByteArrayPrimTyCon)
\ body -> Case arg case_bndr [(DataAlt data_con,vars,body)]
)
- -- Data types with a single constructor, which has a single, primitive-typed arg
- | maybeToBool maybe_boxed_prim_arg_ty
- = newSysLocalDs arg_ty `thenDs` \ case_bndr ->
- newSysLocalDs the_prim_arg_ty `thenDs` \ prim_arg ->
- returnDs (Var prim_arg,
- \ body -> Case arg case_bndr [(DataAlt box_data_con,[prim_arg],body)]
- )
-
| otherwise
= getSrcLocDs `thenDs` \ l ->
pprPanic "unboxArg: " (ppr l <+> ppr arg_ty)
where
- arg_ty = exprType arg
-
- maybe_boxed_prim_arg_ty = maybeBoxedPrimType arg_ty
- (Just (box_data_con, the_prim_arg_ty)) = maybe_boxed_prim_arg_ty
+ 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_arg_ty1 : data_con_arg_ty2 : data_con_arg_ty3 :_)
- = data_con_arg_tys
-
- maybe_arg3_tycon = splitTyConApp_maybe data_con_arg_ty3
- Just (arg3_tycon,_) = maybe_arg3_tycon
+ data_con_arity = dataConSourceArity data_con
+ (data_con_arg_ty1 : _) = data_con_arg_tys
-can'tSeeDataConsPanic thing ty
- = pprPanic
- "ERROR: Can't see the data constructor(s) for _ccall_/_casm_/foreign declaration"
- (hcat [ text thing, text "; type: ", ppr ty
- , text "(try compiling with -fno-prune-tydecls ..)\n"])
+ (_ : _ : data_con_arg_ty3 : _) = data_con_arg_tys
+ maybe_arg3_tycon = splitTyConApp_maybe data_con_arg_ty3
+ Just (arg3_tycon,_) = maybe_arg3_tycon
\end{code}
\begin{code}
-boxResult :: Type -- Type of desired result
- -> DsM (Type, -- Type of the result of the ccall itself
- CoreExpr -> CoreExpr) -- Wrapper for the ccall
- -- to box the result
+boxResult :: Type -> DsM (Type, CoreExpr -> CoreExpr)
+
+-- Takes the result of the user-level ccall:
+-- either (IO t),
+-- or maybe just t for an side-effect-free call
+-- Returns a wrapper for the primitive ccall itself, along with the
+-- type of the result of the primitive ccall. This result type
+-- will be of the form
+-- State# RealWorld -> (# State# RealWorld, t' #)
+-- where t' is the unwrapped form of t. If t is simply (), then
+-- the result type will be
+-- State# RealWorld -> (# State# RealWorld #)
+
boxResult result_ty
- -- Data types with a single nullary constructor
- | (maybeToBool maybe_product_type) && -- Data type
- (null data_con_arg_tys)
- =
- newSysLocalDs realWorldStatePrimTy `thenDs` \ prim_state_id ->
-{-
- wrapUnboxedValue result_ty `thenDs` \ (state_and_prim_datacon,
- state_and_prim_ty, prim_result_id, the_result) ->
- mkConDs ioOkDataCon
- [TyArg result_ty, VarArg (Var prim_state_id), VarArg the_result]
- `thenDs` \ the_pair ->
--}
- let
- the_pair = mkConApp unboxedPairDataCon
- [Type realWorldStatePrimTy, Type result_ty,
- Var prim_state_id,
- Var unitDataConId]
- the_alt = (DataAlt (unboxedTupleCon 1), [prim_state_id], the_pair)
- scrut_ty = mkUnboxedTupleTy 1 [realWorldStatePrimTy]
+ = 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
+ -> mk_alt return_result
+ (resultWrapper io_res_ty) `thenDs` \ (ccall_res_ty, the_alt) ->
+ 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]]
+ in
+ returnDs (realWorldStatePrimTy `mkFunTy` ccall_res_ty, wrap)
+ where
+ return_result state ans = mkConApp unboxedPairDataCon
+ [Type realWorldStatePrimTy, Type io_res_ty,
+ state, ans]
+
+ -- 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) ->
+ let
+ wrap = \ the_call -> Case (App the_call (Var realWorldPrimId))
+ (mkWildId ccall_res_ty)
+ [the_alt]
+ in
+ returnDs (realWorldStatePrimTy `mkFunTy` ccall_res_ty, wrap)
+ where
+ return_result state ans = ans
+ where
+ mk_alt return_result (Nothing, wrap_result)
+ = -- The ccall returns ()
+ newSysLocalDs realWorldStatePrimTy `thenDs` \ state_id ->
+ 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)
+ 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]
+ the_alt = (DataAlt unboxedPairDataCon, [state_id, result_id], the_rhs)
+ in
+ returnDs (ccall_res_ty, the_alt)
+
+
+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
+ = (Just result_ty, \e -> e)
+
+ -- Base case 1: the unit type ()
+ | result_ty == unitTy
+ = (Nothing, \e -> Var unitDataConId)
+
+ | result_ty == boolTy
+ = (Just intPrimTy, \e -> Case e (mkWildId intPrimTy)
+ [(LitAlt (mkMachInt 0),[],Var falseDataConId),
+ (DEFAULT ,[],Var trueDataConId )])
+
+ -- Data types with a single constructor, which has a single arg
+ | is_product_type && data_con_arity == 1
+ = let
+ (maybe_ty, wrapper) = resultWrapper unwrapped_res_ty
+ (unwrapped_res_ty : _) = data_con_arg_tys
in
- returnDs (scrut_ty, \prim_app -> Case prim_app (mkWildId scrut_ty) [the_alt]
- )
-
- -- Data types with a single constructor, which has a single, primitive-typed arg
- | (maybeToBool maybe_product_type) && -- Data type
- not (null data_con_arg_tys) && null other_args_tys && -- Just one arg
- isUnLiftedType the_prim_result_ty -- of primitive type
- =
- newSysLocalDs realWorldStatePrimTy `thenDs` \ prim_state_id ->
- newSysLocalDs the_prim_result_ty `thenDs` \ prim_result_id ->
- newSysLocalDs ccall_res_type `thenDs` \ case_bndr ->
-
- let
- the_result = mkConApp data_con (map Type tycon_arg_tys ++ [Var prim_result_id])
- the_pair = mkConApp unboxedPairDataCon
- [Type realWorldStatePrimTy, Type result_ty,
- Var prim_state_id, the_result]
- the_alt = (DataAlt unboxedPairDataCon, [prim_state_id, prim_result_id], the_pair)
+ (maybe_ty, \e -> mkApps (Var (dataConWrapId data_con))
+ (map Type tycon_arg_tys ++ [wrapper e]))
+
+ -- newtypes
+ | isNewType result_ty
+ = let
+ rep_ty = repType result_ty
+ (maybe_ty, wrapper) = resultWrapper rep_ty
in
- returnDs (ccall_res_type, \prim_app -> Case prim_app case_bndr [the_alt]
- )
+ (maybe_ty, \e -> mkCoerce result_ty rep_ty (wrapper e))
| otherwise
- = pprPanic "boxResult: " (ppr result_ty)
+ = 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
- (the_prim_result_ty : other_args_tys) = data_con_arg_tys
-
- ccall_res_type = mkUnboxedTupleTy 2 [realWorldStatePrimTy, the_prim_result_ty]
-
--- wrap up an unboxed value.
-wrapUnboxedValue :: Type -> DsM (Type, Id, CoreExpr)
-wrapUnboxedValue ty
- | (maybeToBool maybe_product_type) && -- Data type
- not (null data_con_arg_tys) && null other_args_tys && -- Just one arg
- isUnLiftedType the_prim_result_ty -- of primitive type
- =
- newSysLocalDs the_prim_result_ty `thenDs` \ prim_result_id ->
- let
- the_result = mkConApp data_con (map Type tycon_arg_tys ++ [Var prim_result_id])
- in
- returnDs (ccall_res_type, prim_result_id, the_result)
-
- -- Data types with a single nullary constructor
- | (maybeToBool maybe_product_type) && -- Data type
- (null data_con_arg_tys)
- =
- let
- scrut_ty = mkUnboxedTupleTy 1 [realWorldStatePrimTy]
- in
- returnDs (scrut_ty, unitDataConId, Var unitDataConId)
-
- | otherwise
- = pprPanic "boxResult: " (ppr ty)
- where
- maybe_product_type = splitProductType_maybe ty
- Just (tycon, tycon_arg_tys, data_con, data_con_arg_tys) = maybe_product_type
- (the_prim_result_ty : other_args_tys) = data_con_arg_tys
- ccall_res_type = mkUnboxedTupleTy 2 [realWorldStatePrimTy, the_prim_result_ty]
+ data_con_arity = dataConSourceArity data_con
\end{code}
projects / ghc-hetmet.git / blobdiff