X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FdeSugar%2FDsCCall.lhs;h=51a22bae19dfc0af377e008354b4e488a02eafcc;hb=8f762bf5c40f89022c1da71f7c10fdfc64099d5d;hp=c500505080133fd317173129edd206d5b0d8fd1c;hpb=7caedc52dde9fb7f773fb3a1d5fc0f7b2d8de848;p=ghc-hetmet.git diff --git a/ghc/compiler/deSugar/DsCCall.lhs b/ghc/compiler/deSugar/DsCCall.lhs index c500505..51a22ba 100644 --- a/ghc/compiler/deSugar/DsCCall.lhs +++ b/ghc/compiler/deSugar/DsCCall.lhs @@ -1,17 +1,15 @@ % -% (c) The AQUA Project, Glasgow University, 1994-1996 +% (c) The AQUA Project, Glasgow University, 1994-1998 % \section[DsCCall]{Desugaring \tr{_ccall_}s and \tr{_casm_}s} \begin{code} module DsCCall - ( - dsCCall - , getIoOkDataCon - , unboxArg - , boxResult - , wrapUnboxedValue - , can'tSeeDataConsPanic + ( dsCCall + , mkCCall + , unboxArg + , boxResult + , resultWrapper ) where #include "HsVersions.h" @@ -19,26 +17,32 @@ module DsCCall import CoreSyn import DsMonad -import DsUtils -import TcHsSyn ( maybeBoxedPrimType ) -import CoreUtils ( coreExprType ) -import Id ( Id, dataConArgTys, idType ) +import CoreUtils ( exprType, mkCoerce ) +import Id ( mkWildId ) +import MkId ( mkCCallOpId, realWorldPrimId ) import Maybes ( maybeToBool ) -import PrelVals ( packStringForCId ) -import PrimOp ( PrimOp(..) ) +import PrimOp ( CCall(..), CCallTarget(..) ) +import DataCon ( splitProductType_maybe, dataConSourceArity, dataConWrapId ) import CallConv -import Type ( isUnpointedType, splitAlgTyConApp_maybe, - splitTyConApp_maybe, splitFunTys, splitForAllTys, +import Type ( isUnLiftedType, splitAlgTyConApp_maybe, mkFunTys, + splitTyConApp_maybe, tyVarsOfType, mkForAllTys, + isNewType, repType, isUnLiftedType, mkFunTy, mkTyConApp, Type ) -import TyCon ( tyConDataCons ) -import TysPrim ( byteArrayPrimTy, realWorldStatePrimTy, - byteArrayPrimTyCon, mutableByteArrayPrimTyCon ) -import TysWiredIn ( getStatePairingConInfo, - unitDataCon, stringTy, - realWorldStateTy, stateDataCon +import TysPrim ( realWorldStatePrimTy, + byteArrayPrimTyCon, mutableByteArrayPrimTyCon, intPrimTy ) +import TysWiredIn ( unitDataConId, + unboxedSingletonDataCon, unboxedPairDataCon, + unboxedSingletonTyCon, unboxedPairTyCon, + boolTy, trueDataCon, falseDataCon, + trueDataConId, falseDataConId, unitTy + ) +import Literal ( mkMachInt ) +import CStrings ( CLabelString ) +import PrelNames ( Unique, hasKey, ioTyConKey ) +import VarSet ( varSetElems ) import Outputable \end{code} @@ -78,34 +82,44 @@ follows: \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 label args may_gc is_asm io_result_ty - = newSysLocalDs realWorldStatePrimTy `thenDs` \ old_s -> - - mapAndUnzipDs unboxArg args `thenDs` \ (unboxed_args, arg_wrappers) -> - let - final_args = Var old_s : unboxed_args - (ioOkDataCon, _, result_ty) = getIoOkDataCon io_result_ty - in - - boxResult ioOkDataCon result_ty `thenDs` \ (final_result_ty, res_wrapper) -> - +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) -> + getUniqueDs `thenDs` \ uniq -> let - the_ccall_op = CCallOp (Left label) is_asm may_gc cCallConv - (map coreExprType final_args) - final_result_ty + the_ccall = CCall (StaticTarget lbl) is_asm may_gc cCallConv + the_prim_app = mkCCall uniq the_ccall unboxed_args ccall_result_ty in - mkPrimDs the_ccall_op (map VarArg final_args) `thenDs` \ the_prim_app -> - let - the_body = foldr ($) (res_wrapper the_prim_app) arg_wrappers - in - returnDs (Lam (ValBinder old_s) the_body) + returnDs (foldr ($) (res_wrapper the_prim_app) arg_wrappers) + +mkCCall :: Unique -> CCall + -> [CoreExpr] -- Args + -> Type -- Result type + -> CoreExpr +-- Construct the ccall. The only tricky bit is that the ccall Id should have +-- no free vars, so if any of the arg tys do we must give it a polymorphic type. +-- [I forget *why* it should have no free vars!] +-- For example: +-- mkCCall ... [s::StablePtr (a->b), x::Addr, c::Char] +-- +-- 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 + 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 \end{code} \begin{code} @@ -113,213 +127,178 @@ unboxArg :: CoreExpr -- The supplied argument -> 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 :-) - -- - | isUnpointedType arg_ty +unboxArg arg + -- Unlifted types: nothing to unbox + | isUnLiftedType arg_ty = returnDs (arg, \body -> body) - -- Strings - | arg_ty == stringTy - = newSysLocalDs byteArrayPrimTy `thenDs` \ prim_arg -> - mkAppDs (Var packStringForCId) [VarArg arg] `thenDs` \ pack_appn -> + -- 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 pack_appn (PrimAlts [] - (BindDefault prim_arg body)) - ) + \ body -> Case (Case arg (mkWildId arg_ty) + [(DataAlt falseDataCon,[],mkIntLit 0), + (DataAlt trueDataCon, [],mkIntLit 1)]) + prim_arg + [(DEFAULT,[],body)]) - | null data_cons - -- oops: we can't see the data constructors!!! - = can'tSeeDataConsPanic "argument" arg_ty + -- 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_data_type && - length data_con_arg_tys == 2 && - maybeToBool maybe_arg2_tycon && - (arg2_tycon == byteArrayPrimTyCon || - arg2_tycon == mutableByteArrayPrimTyCon) + | is_product_type && + data_con_arity == 3 && + maybeToBool maybe_arg3_tycon && + (arg3_tycon == byteArrayPrimTyCon || + arg3_tycon == mutableByteArrayPrimTyCon) -- and, of course, it is an instance of CCallable - = newSysLocalsDs data_con_arg_tys `thenDs` \ vars@[ixs_var, arr_cts_var] -> + = newSysLocalDs arg_ty `thenDs` \ case_bndr -> + newSysLocalsDs data_con_arg_tys `thenDs` \ vars@[l_var, r_var, arr_cts_var] -> returnDs (Var arr_cts_var, - \ body -> Case arg (AlgAlts [(the_data_con,vars,body)] - NoDefault) - ) - - -- Data types with a single constructor, which has a single, primitive-typed arg - | maybeToBool maybe_boxed_prim_arg_ty - = newSysLocalDs the_prim_arg_ty `thenDs` \ prim_arg -> - returnDs (Var prim_arg, - \ body -> Case arg (AlgAlts [(box_data_con,[prim_arg],body)] - NoDefault) + \ body -> Case arg case_bndr [(DataAlt data_con,vars,body)] ) | otherwise = getSrcLocDs `thenDs` \ l -> pprPanic "unboxArg: " (ppr l <+> ppr arg_ty) where - arg_ty = coreExprType arg - - maybe_boxed_prim_arg_ty = maybeBoxedPrimType arg_ty - (Just (box_data_con, the_prim_arg_ty)) = maybe_boxed_prim_arg_ty - - maybe_data_type = splitAlgTyConApp_maybe arg_ty - is_data_type = maybeToBool maybe_data_type - (Just (tycon, tycon_arg_tys, data_cons)) = maybe_data_type - (the_data_con : other_data_cons) = data_cons - - data_con_arg_tys = dataConArgTys the_data_con tycon_arg_tys - (data_con_arg_ty1 : data_con_arg_ty2 : _) = data_con_arg_tys - - maybe_arg2_tycon = splitTyConApp_maybe data_con_arg_ty2 - Just (arg2_tycon,_) = maybe_arg2_tycon - -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"]) + 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 + Just (arg3_tycon,_) = maybe_arg3_tycon \end{code} \begin{code} -boxResult :: Id -- IOok constructor - -> 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 ioOkDataCon result_ty - | null data_cons - -- oops! can't see the data constructors - = can'tSeeDataConsPanic "result" result_ty - - -- Data types with a single constructor, which has a single, primitive-typed arg - | (maybeToBool maybe_data_type) && -- Data type - (null other_data_cons) && -- Just one constr - not (null data_con_arg_tys) && null other_args_tys && -- Just one arg - isUnpointedType the_prim_result_ty -- of primitive type - = - 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_alt = (state_and_prim_datacon, [prim_state_id, prim_result_id], the_pair) +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 + = 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]) | io_tycon `hasKey` 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 = 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 = mkTyConApp unboxedPairTyCon [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 (state_and_prim_ty, - \prim_app -> Case prim_app (AlgAlts [the_alt] NoDefault) - ) - - -- Data types with a single nullary constructor - | (maybeToBool maybe_data_type) && -- Data type - (null other_data_cons) && -- Just one constr - (null data_con_arg_tys) - = - newSysLocalDs realWorldStatePrimTy `thenDs` \ prim_state_id -> - - mkConDs ioOkDataCon - [TyArg result_ty, VarArg (Var prim_state_id), VarArg (Var unitDataCon)] - `thenDs` \ the_pair -> - - let - the_alt = (stateDataCon, [prim_state_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 (realWorldStateTy, - \prim_app -> Case prim_app (AlgAlts [the_alt] NoDefault) - ) + (maybe_ty, \e -> mkCoerce result_ty rep_ty (wrapper e)) | otherwise - = pprPanic "boxResult: " (ppr result_ty) + = pprPanic "resultWrapper" (ppr result_ty) where - maybe_data_type = splitAlgTyConApp_maybe result_ty - Just (tycon, tycon_arg_tys, data_cons) = maybe_data_type - (the_data_con : other_data_cons) = data_cons - - data_con_arg_tys = dataConArgTys the_data_con tycon_arg_tys - (the_prim_result_ty : other_args_tys) = data_con_arg_tys - --- (state_and_prim_datacon, state_and_prim_ty) = getStatePairingConInfo the_prim_result_ty - --- wrap up an unboxed value. -wrapUnboxedValue :: Type -> DsM (Id, Type, Id, CoreExpr) -wrapUnboxedValue ty - | null data_cons - -- oops! can't see the data constructors - = can'tSeeDataConsPanic "result" ty - -- Data types with a single constructor, which has a single, primitive-typed arg - | (maybeToBool maybe_data_type) && -- Data type - (null other_data_cons) && -- Just one constr - not (null data_con_arg_tys) && null other_args_tys && -- Just one arg - isUnpointedType the_prim_result_ty -- of primitive type - = - newSysLocalDs the_prim_result_ty `thenDs` \ prim_result_id -> - mkConDs the_data_con (map TyArg tycon_arg_tys ++ - [VarArg (Var prim_result_id)]) `thenDs` \ the_result -> - returnDs (state_and_prim_datacon, state_and_prim_ty, prim_result_id, the_result) - - -- Data types with a single nullary constructor - | (maybeToBool maybe_data_type) && -- Data type - (null other_data_cons) && -- Just one constr - (null data_con_arg_tys) - = - let unit = unitDataCon in - returnDs (stateDataCon, realWorldStateTy, unit, Var unit) - | otherwise - = pprPanic "boxResult: " (ppr ty) - where - maybe_data_type = splitAlgTyConApp_maybe ty - Just (tycon, tycon_arg_tys, data_cons) = maybe_data_type - (the_data_con : other_data_cons) = data_cons - - data_con_arg_tys = dataConArgTys the_data_con tycon_arg_tys - (the_prim_result_ty : other_args_tys) = data_con_arg_tys - (state_and_prim_datacon, state_and_prim_ty) = getStatePairingConInfo the_prim_result_ty - + 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} - -This grimy bit of code is for digging out the IOok constructor from an -application of the the IO type. The constructor is needed for -wrapping the result of a _ccall_. The alternative is to wire-in IO, -which brings a whole heap of junk with it. - -If the representation of IO changes, this will probably have to be -brought in line with the new definition. - -newtype IO a = IO (State# RealWorld -> IOResult a) - -the constructor IO has type (State# RealWorld -> IOResult a) -> IO a - -\begin{code} -getIoOkDataCon :: Type -- IO t - -> (Id, Id, Type) -- Returns (IOok, IO, t) - -getIoOkDataCon io_ty - = let - Just (ioTyCon, [t]) = splitTyConApp_maybe io_ty - [ioDataCon] = tyConDataCons ioTyCon - ioDataConTy = idType ioDataCon - (_, ioDataConTy') = splitForAllTys ioDataConTy - ([arg_ty], _) = splitFunTys ioDataConTy' - (_, io_result_ty) = splitFunTys arg_ty - Just (io_result_tycon, _) = splitTyConApp_maybe io_result_ty - [ioOkDataCon,ioFailDataCon] = tyConDataCons io_result_tycon - in - (ioOkDataCon, ioDataCon, t) -\end{code} - -Another way to do it, more sensitive: - - case ioDataConTy of - ForAll _ (FunTy (FunTy _ (AppTy (TyConTy ioResultTyCon _) _)) _) -> - let [ioOkDataCon,ioFailDataCon] = tyConDataCons ioResultTyCon - in - (ioOkDataCon, result_ty) - _ -> pprPanic "getIoOkDataCon: " (ppr PprDebug ioDataConTy)