X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FdeSugar%2FDsCCall.lhs;h=5ee47807de1f6d089bcede6277afd771cd05cd4a;hb=76293b141bba4c15a6fd619dd980502e98614790;hp=3badf9792208048438a70ba9f42d50d4583fb390;hpb=dcef38bab91d45b56f7cf3ceeec96303d93728bb;p=ghc-hetmet.git diff --git a/ghc/compiler/deSugar/DsCCall.lhs b/ghc/compiler/deSugar/DsCCall.lhs index 3badf97..5ee4780 100644 --- a/ghc/compiler/deSugar/DsCCall.lhs +++ b/ghc/compiler/deSugar/DsCCall.lhs @@ -1,41 +1,59 @@ % -% (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} -#include "HsVersions.h" - -module DsCCall ( dsCCall ) where +module DsCCall + ( dsCCall + , mkFCall + , unboxArg + , boxResult + , resultWrapper + ) where -IMP_Ubiq() +#include "HsVersions.h" import CoreSyn import DsMonad -import DsUtils -import CoreUtils ( coreExprType ) -import Id ( dataConArgTys ) +import CoreUtils ( exprType, mkCoerce ) +import Id ( Id, mkWildId, idType ) +import MkId ( mkFCallId, realWorldPrimId, mkPrimOpId ) import Maybes ( maybeToBool ) -import PprStyle ( PprStyle(..) ) -import PprType ( GenType{-instances-} ) -import Pretty -import PrelVals ( packStringForCId ) -import PrimOp ( PrimOp(..) ) -import Type ( isPrimType, maybeAppDataTyConExpandingDicts, maybeAppTyCon, - eqTy, maybeBoxedPrimType, SYN_IE(Type) ) -import TysPrim ( byteArrayPrimTy, realWorldTy, realWorldStatePrimTy, - byteArrayPrimTyCon, mutableByteArrayPrimTyCon ) -import TysWiredIn ( getStatePairingConInfo, - realWorldStateTy, stateDataCon, pairDataCon, unitDataCon, - stringTy +import ForeignCall ( ForeignCall(..), CCallSpec(..), CCallTarget(..), Safety, CCallConv(..) ) +import DataCon ( splitProductType_maybe, dataConSourceArity, dataConWrapId ) +import ForeignCall ( ForeignCall, CCallTarget(..) ) + +import TcType ( tcSplitTyConApp_maybe ) +import Type ( Type, isUnLiftedType, mkFunTys, mkFunTy, + tyVarsOfType, mkForAllTys, mkTyConApp, + isPrimitiveType, eqType, + splitTyConApp_maybe, splitNewType_maybe ) -import Util ( pprPanic, pprError, panic ) -#if __GLASGOW_HASKELL__ >= 202 -import Outputable ( Outputable(..) ) -#endif +import PrimOp ( PrimOp(..) ) +import TysPrim ( realWorldStatePrimTy, + byteArrayPrimTyCon, mutableByteArrayPrimTyCon, + intPrimTy, foreignObjPrimTy + ) +import TyCon ( TyCon, tyConDataCons ) +import TysWiredIn ( unitDataConId, + unboxedSingletonDataCon, unboxedPairDataCon, + unboxedSingletonTyCon, unboxedPairTyCon, + trueDataCon, falseDataCon, + trueDataConId, falseDataConId + ) +import Literal ( mkMachInt ) +import CStrings ( CLabelString ) +import PrelNames ( Unique, hasKey, ioTyConKey, boolTyConKey, unitTyConKey, + int8TyConKey, int16TyConKey, int32TyConKey, + word8TyConKey, word16TyConKey, word32TyConKey + ) +import VarSet ( varSetElems ) +import Constants ( wORD_SIZE) +import Outputable \end{code} Desugaring of @ccall@s consists of adding some state manipulation, @@ -74,30 +92,46 @@ 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 + -> Safety -- Safety of the call -> Bool -- True <=> really a "_casm_" - -> Type -- Type of the result (a boxed-prim type) + -> Type -- Type of the result: IO t -> DsM CoreExpr -dsCCall label args may_gc is_asm result_ty - = newSysLocalDs realWorldStateTy `thenDs` \ old_s -> - - mapAndUnzipDs unboxArg (Var old_s : args) `thenDs` \ (final_args, arg_wrappers) -> - - boxResult 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 label is_asm may_gc - (map coreExprType final_args) - final_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 - 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) + +mkFCall :: Unique -> ForeignCall + -> [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 +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_fcall_id = mkFCallId uniq the_fcall ty \end{code} \begin{code} @@ -105,144 +139,228 @@ 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 :-) - -- - | isPrimType arg_ty +unboxArg arg + -- Primtive types: nothing to unbox + | isPrimitiveType arg_ty = returnDs (arg, \body -> body) - -- Strings - | arg_ty `eqTy` stringTy - -- ToDo (ADR): - allow synonyms of Strings too? - = newSysLocalDs byteArrayPrimTy `thenDs` \ prim_arg -> - mkAppDs (Var packStringForCId) [VarArg arg] `thenDs` \ pack_appn -> + -- Recursive newtypes + | Just rep_ty <- splitNewType_maybe arg_ty + = unboxArg (mkCoerce rep_ty arg_ty arg) + + -- Booleans + | Just (tc,_) <- splitTyConApp_maybe arg_ty, + tc `hasKey` boolTyConKey + = 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't_see_datacons_error "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) + -- We're looking for values of type ByteArray, MutableByteArray + -- data ByteArray ix = ByteArray ix ix ByteArray# + -- data MutableByteArray s ix = MutableByteArray ix ix (MutableByteArray# s) + | 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 - = pprPanic "unboxArg: " (ppr PprDebug arg_ty) + = 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 = maybeAppDataTyConExpandingDicts 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 = maybeAppTyCon data_con_arg_ty2 - Just (arg2_tycon,_) = maybe_arg2_tycon - -can't_see_datacons_error thing ty - = pprError "ERROR: Can't see the data constructor(s) for _ccall_/_casm_ " - (hcat [text thing, text "; type: ", ppr PprForUser ty]) + 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 :: 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 result_ty - | null data_cons - -- oops! can't see the data constructors - = can't_see_datacons_error "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 - isPrimType the_prim_result_ty -- of primitive type - = - newSysLocalDs realWorldStatePrimTy `thenDs` \ prim_state_id -> - newSysLocalDs the_prim_result_ty `thenDs` \ prim_result_id -> - - mkConDs stateDataCon [TyArg realWorldTy, VarArg (Var prim_state_id)] `thenDs` \ new_state -> - mkConDs the_data_con (map TyArg tycon_arg_tys ++ [VarArg (Var prim_result_id)]) `thenDs` \ the_result -> - - mkConDs pairDataCon - [TyArg result_ty, TyArg realWorldStateTy, VarArg the_result, VarArg new_state] - `thenDs` \ the_pair -> - let - the_alt = (state_and_prim_datacon, [prim_state_id, prim_result_id], the_pair) +boxResult :: [Id] -> 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 #) + +-- 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 tcSplitTyConApp_maybe result_ty of + -- This split absolutely has to be a tcSplit, because we must + -- see the IO type; and it's a newtype which is transparent to splitTyConApp. + + -- The result is IO t, so wrap the result in an IO constructor + Just (io_tycon, [io_res_ty]) | io_tycon `hasKey` ioTyConKey + -> mk_alt return_result + (resultWrapper io_res_ty) `thenDs` \ (ccall_res_ty, the_alt) -> + newSysLocalDs realWorldStatePrimTy `thenDs` \ state_id -> + let + io_data_con = head (tyConDataCons io_tycon) + 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 () + 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 + 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 prim_res_ty `thenDs` \ result_id -> + let + 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 + | not (idType v `eqType` 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 + | isPrimitiveType result_ty + = (Just result_ty, \e -> e) + + -- Base case 2: the unit type () + | Just (tc,_) <- maybe_tc_app, tc `hasKey` unitTyConKey + = (Nothing, \e -> Var unitDataConId) + + -- Base case 3: the boolean type + | Just (tc,_) <- maybe_tc_app, tc `hasKey` boolTyConKey + = (Just intPrimTy, \e -> Case e (mkWildId intPrimTy) + [(DEFAULT ,[],Var trueDataConId ), + (LitAlt (mkMachInt 0),[],Var falseDataConId)]) + + -- Recursive newtypes + | Just rep_ty <- splitNewType_maybe result_ty + = let + (maybe_ty, wrapper) = resultWrapper rep_ty 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 stateDataCon [TyArg realWorldTy, VarArg (Var prim_state_id)] - `thenDs` \ new_state -> - mkConDs pairDataCon - [TyArg result_ty, TyArg realWorldStateTy, VarArg (Var unitDataCon), VarArg new_state] - `thenDs` \ the_pair -> - - let - the_alt = (stateDataCon, [prim_state_id], the_pair) + (maybe_ty, \e -> mkCoerce result_ty rep_ty (wrapper e)) + + -- Data types with a single constructor, which has a single arg + | Just (tycon, tycon_arg_tys, data_con, data_con_arg_tys) <- splitProductType_maybe result_ty, + dataConSourceArity data_con == 1 + = let + (maybe_ty, wrapper) = resultWrapper unwrapped_res_ty + (unwrapped_res_ty : _) = data_con_arg_tys + narrow_wrapper = maybeNarrow tycon in - returnDs (realWorldStateTy, - \prim_app -> Case prim_app (AlgAlts [the_alt] NoDefault) - ) + (maybe_ty, \e -> mkApps (Var (dataConWrapId data_con)) + (map Type tycon_arg_tys ++ [wrapper (narrow_wrapper e)])) | otherwise - = pprPanic "boxResult: " (ppr PprDebug result_ty) - + = pprPanic "resultWrapper" (ppr result_ty) where - maybe_data_type = maybeAppDataTyConExpandingDicts 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 + maybe_tc_app = splitTyConApp_maybe result_ty + +-- When the result of a foreign call is smaller than the word size, we +-- need to sign- or zero-extend the result up to the word size. The C +-- standard appears to say that this is the responsibility of the +-- caller, not the callee. + +maybeNarrow :: TyCon -> (CoreExpr -> CoreExpr) +maybeNarrow tycon + | tycon `hasKey` int8TyConKey = \e -> App (Var (mkPrimOpId Narrow8IntOp)) e + | tycon `hasKey` int16TyConKey = \e -> App (Var (mkPrimOpId Narrow16IntOp)) e + | tycon `hasKey` int32TyConKey + && wORD_SIZE > 4 = \e -> App (Var (mkPrimOpId Narrow32IntOp)) e + + | tycon `hasKey` word8TyConKey = \e -> App (Var (mkPrimOpId Narrow8WordOp)) e + | tycon `hasKey` word16TyConKey = \e -> App (Var (mkPrimOpId Narrow16WordOp)) e + | tycon `hasKey` word32TyConKey + && wORD_SIZE > 4 = \e -> App (Var (mkPrimOpId Narrow32WordOp)) e + | otherwise = id \end{code} -