2 % (c) The University of Glasgow 2002
4 \section[ByteCodeGen]{Generate bytecode from Core}
7 module ByteCodeGen ( UnlinkedBCO, byteCodeGen, coreExprToBCOs ) where
9 #include "HsVersions.h"
12 import ByteCodeFFI ( mkMarshalCode, moan64 )
13 import ByteCodeAsm ( CompiledByteCode(..), UnlinkedBCO,
14 assembleBCO, assembleBCOs, iNTERP_STACK_CHECK_THRESH )
15 import ByteCodeLink ( lookupStaticPtr )
18 import Name ( Name, getName, mkSystemVarName )
21 import ForeignCall ( ForeignCall(..), CCallTarget(..), CCallSpec(..) )
22 import HscTypes ( TypeEnv, typeEnvTyCons, typeEnvClasses )
23 import CoreUtils ( exprType )
25 import PprCore ( pprCoreExpr )
26 import Literal ( Literal(..), literalType )
27 import PrimOp ( PrimOp(..) )
28 import CoreFVs ( freeVars )
29 import Type ( isUnLiftedType, splitTyConApp_maybe )
30 import DataCon ( DataCon, dataConTag, fIRST_TAG, dataConTyCon,
31 isUnboxedTupleCon, isNullaryRepDataCon, dataConWorkId,
33 import TyCon ( TyCon, tyConFamilySize, isDataTyCon,
34 tyConDataCons, isUnboxedTupleTyCon )
35 import Class ( Class, classTyCon )
36 import Type ( Type, repType, splitFunTys, dropForAlls, pprType )
38 import DataCon ( dataConRepArity )
39 import Var ( isTyVar )
40 import VarSet ( VarSet, varSetElems )
41 import TysPrim ( arrayPrimTyCon, mutableArrayPrimTyCon,
42 byteArrayPrimTyCon, mutableByteArrayPrimTyCon
44 import DynFlags ( DynFlags, DynFlag(..) )
45 import ErrUtils ( showPass, dumpIfSet_dyn )
46 import Unique ( mkPseudoUniqueE )
47 import FastString ( FastString(..), unpackFS )
48 import Panic ( GhcException(..) )
49 import SMRep ( typeCgRep, arrWordsHdrSize, arrPtrsHdrSize, StgWord,
50 CgRep(..), cgRepSizeW, isFollowableArg, idCgRep )
51 import Bitmap ( intsToReverseBitmap, mkBitmap )
53 import Constants ( wORD_SIZE )
55 import Data.List ( intersperse, sortBy, zip4, zip6, partition )
56 import Foreign ( Ptr, castPtr, mallocBytes, pokeByteOff, Word8,
58 import Foreign.C ( CInt )
59 import Control.Exception ( throwDyn )
61 import GHC.Exts ( Int(..), ByteArray# )
63 import Control.Monad ( when )
64 import Data.Char ( ord, chr )
66 -- -----------------------------------------------------------------------------
67 -- Generating byte code for a complete module
69 byteCodeGen :: DynFlags
72 -> IO CompiledByteCode
73 byteCodeGen dflags binds tycs
74 = do showPass dflags "ByteCodeGen"
76 let flatBinds = [ (bndr, freeVars rhs)
77 | (bndr, rhs) <- flattenBinds binds]
79 (BcM_State final_ctr mallocd, proto_bcos)
80 <- runBc (mapM schemeTopBind flatBinds)
82 when (notNull mallocd)
83 (panic "ByteCodeGen.byteCodeGen: missing final emitBc?")
85 dumpIfSet_dyn dflags Opt_D_dump_BCOs
86 "Proto-BCOs" (vcat (intersperse (char ' ') (map ppr proto_bcos)))
88 assembleBCOs proto_bcos tycs
90 -- -----------------------------------------------------------------------------
91 -- Generating byte code for an expression
93 -- Returns: (the root BCO for this expression,
94 -- a list of auxilary BCOs resulting from compiling closures)
95 coreExprToBCOs :: DynFlags
98 coreExprToBCOs dflags expr
99 = do showPass dflags "ByteCodeGen"
101 -- create a totally bogus name for the top-level BCO; this
102 -- should be harmless, since it's never used for anything
103 let invented_name = mkSystemVarName (mkPseudoUniqueE 0) FSLIT("ExprTopLevel")
104 invented_id = mkLocalId invented_name (panic "invented_id's type")
106 (BcM_State final_ctr mallocd, proto_bco)
107 <- runBc (schemeTopBind (invented_id, freeVars expr))
109 when (notNull mallocd)
110 (panic "ByteCodeGen.coreExprToBCOs: missing final emitBc?")
112 dumpIfSet_dyn dflags Opt_D_dump_BCOs "Proto-BCOs" (ppr proto_bco)
114 assembleBCO proto_bco
117 -- -----------------------------------------------------------------------------
118 -- Compilation schema for the bytecode generator
120 type BCInstrList = OrdList BCInstr
122 type Sequel = Int -- back off to this depth before ENTER
124 -- Maps Ids to the offset from the stack _base_ so we don't have
125 -- to mess with it after each push/pop.
126 type BCEnv = FiniteMap Id Int -- To find vars on the stack
128 ppBCEnv :: BCEnv -> SDoc
131 $$ nest 4 (vcat (map pp_one (sortBy cmp_snd (fmToList p))))
134 pp_one (var, offset) = int offset <> colon <+> ppr var <+> ppr (idCgRep var)
135 cmp_snd x y = compare (snd x) (snd y)
137 -- Create a BCO and do a spot of peephole optimisation on the insns
142 -> Either [AnnAlt Id VarSet] (AnnExpr Id VarSet)
146 -> Bool -- True <=> is a return point, rather than a function
149 mkProtoBCO nm instrs_ordlist origin arity bitmap_size bitmap
150 is_ret mallocd_blocks
153 protoBCOInstrs = maybe_with_stack_check,
154 protoBCOBitmap = bitmap,
155 protoBCOBitmapSize = bitmap_size,
156 protoBCOArity = arity,
157 protoBCOExpr = origin,
158 protoBCOPtrs = mallocd_blocks
161 -- Overestimate the stack usage (in words) of this BCO,
162 -- and if >= iNTERP_STACK_CHECK_THRESH, add an explicit
163 -- stack check. (The interpreter always does a stack check
164 -- for iNTERP_STACK_CHECK_THRESH words at the start of each
165 -- BCO anyway, so we only need to add an explicit on in the
166 -- (hopefully rare) cases when the (overestimated) stack use
167 -- exceeds iNTERP_STACK_CHECK_THRESH.
168 maybe_with_stack_check
170 -- don't do stack checks at return points;
171 -- everything is aggregated up to the top BCO
172 -- (which must be a function)
173 | stack_overest >= 65535
174 = pprPanic "mkProtoBCO: stack use won't fit in 16 bits"
176 | stack_overest >= iNTERP_STACK_CHECK_THRESH
177 = STKCHECK stack_overest : peep_d
179 = peep_d -- the supposedly common case
181 stack_overest = sum (map bciStackUse peep_d)
183 -- Merge local pushes
184 peep_d = peep (fromOL instrs_ordlist)
186 peep (PUSH_L off1 : PUSH_L off2 : PUSH_L off3 : rest)
187 = PUSH_LLL off1 (off2-1) (off3-2) : peep rest
188 peep (PUSH_L off1 : PUSH_L off2 : rest)
189 = PUSH_LL off1 (off2-1) : peep rest
195 argBits :: [CgRep] -> [Bool]
198 | isFollowableArg rep = False : argBits args
199 | otherwise = take (cgRepSizeW rep) (repeat True) ++ argBits args
201 -- -----------------------------------------------------------------------------
204 -- Compile code for the right-hand side of a top-level binding
206 schemeTopBind :: (Id, AnnExpr Id VarSet) -> BcM (ProtoBCO Name)
209 schemeTopBind (id, rhs)
210 | Just data_con <- isDataConWorkId_maybe id,
211 isNullaryRepDataCon data_con
212 = -- Special case for the worker of a nullary data con.
213 -- It'll look like this: Nil = /\a -> Nil a
214 -- If we feed it into schemeR, we'll get
216 -- because mkConAppCode treats nullary constructor applications
217 -- by just re-using the single top-level definition. So
218 -- for the worker itself, we must allocate it directly.
219 emitBc (mkProtoBCO (getName id) (toOL [PACK data_con 0, ENTER])
220 (Right rhs) 0 0 [{-no bitmap-}] False{-not alts-})
223 = schemeR [{- No free variables -}] (id, rhs)
225 -- -----------------------------------------------------------------------------
228 -- Compile code for a right-hand side, to give a BCO that,
229 -- when executed with the free variables and arguments on top of the stack,
230 -- will return with a pointer to the result on top of the stack, after
231 -- removing the free variables and arguments.
233 -- Park the resulting BCO in the monad. Also requires the
234 -- variable to which this value was bound, so as to give the
235 -- resulting BCO a name.
237 schemeR :: [Id] -- Free vars of the RHS, ordered as they
238 -- will appear in the thunk. Empty for
239 -- top-level things, which have no free vars.
240 -> (Id, AnnExpr Id VarSet)
241 -> BcM (ProtoBCO Name)
242 schemeR fvs (nm, rhs)
246 $$ (ppr.filter (not.isTyVar).varSetElems.fst) rhs
247 $$ pprCoreExpr (deAnnotate rhs)
253 = schemeR_wrk fvs nm rhs (collect [] rhs)
255 collect xs (_, AnnNote note e) = collect xs e
256 collect xs (_, AnnLam x e) = collect (if isTyVar x then xs else (x:xs)) e
257 collect xs (_, not_lambda) = (reverse xs, not_lambda)
259 schemeR_wrk fvs nm original_body (args, body)
261 all_args = reverse args ++ fvs
262 arity = length all_args
263 -- all_args are the args in reverse order. We're compiling a function
264 -- \fv1..fvn x1..xn -> e
265 -- i.e. the fvs come first
267 szsw_args = map idSizeW all_args
268 szw_args = sum szsw_args
269 p_init = listToFM (zip all_args (mkStackOffsets 0 szsw_args))
271 -- make the arg bitmap
272 bits = argBits (reverse (map idCgRep all_args))
273 bitmap_size = length bits
274 bitmap = mkBitmap bits
276 schemeE szw_args 0 p_init body `thenBc` \ body_code ->
277 emitBc (mkProtoBCO (getName nm) body_code (Right original_body)
278 arity bitmap_size bitmap False{-not alts-})
281 fvsToEnv :: BCEnv -> VarSet -> [Id]
282 -- Takes the free variables of a right-hand side, and
283 -- delivers an ordered list of the local variables that will
284 -- be captured in the thunk for the RHS
285 -- The BCEnv argument tells which variables are in the local
286 -- environment: these are the ones that should be captured
288 -- The code that constructs the thunk, and the code that executes
289 -- it, have to agree about this layout
290 fvsToEnv p fvs = [v | v <- varSetElems fvs,
291 isId v, -- Could be a type variable
294 -- -----------------------------------------------------------------------------
297 -- Compile code to apply the given expression to the remaining args
298 -- on the stack, returning a HNF.
299 schemeE :: Int -> Sequel -> BCEnv -> AnnExpr' Id VarSet -> BcM BCInstrList
301 -- Delegate tail-calls to schemeT.
302 schemeE d s p e@(AnnApp f a)
305 schemeE d s p e@(AnnVar v)
306 | not (isUnLiftedType v_type)
307 = -- Lifted-type thing; push it in the normal way
311 = -- Returning an unlifted value.
312 -- Heave it on the stack, SLIDE, and RETURN.
313 pushAtom d p (AnnVar v) `thenBc` \ (push, szw) ->
314 returnBc (push -- value onto stack
315 `appOL` mkSLIDE szw (d-s) -- clear to sequel
316 `snocOL` RETURN_UBX v_rep) -- go
319 v_rep = typeCgRep v_type
321 schemeE d s p (AnnLit literal)
322 = pushAtom d p (AnnLit literal) `thenBc` \ (push, szw) ->
323 let l_rep = typeCgRep (literalType literal)
324 in returnBc (push -- value onto stack
325 `appOL` mkSLIDE szw (d-s) -- clear to sequel
326 `snocOL` RETURN_UBX l_rep) -- go
329 schemeE d s p (AnnLet (AnnNonRec x (_,rhs)) (_,body))
330 | (AnnVar v, args_r_to_l) <- splitApp rhs,
331 Just data_con <- isDataConWorkId_maybe v,
332 dataConRepArity data_con == length args_r_to_l
333 = -- Special case for a non-recursive let whose RHS is a
334 -- saturatred constructor application.
335 -- Just allocate the constructor and carry on
336 mkConAppCode d s p data_con args_r_to_l `thenBc` \ alloc_code ->
337 schemeE (d+1) s (addToFM p x d) body `thenBc` \ body_code ->
338 returnBc (alloc_code `appOL` body_code)
340 -- General case for let. Generates correct, if inefficient, code in
342 schemeE d s p (AnnLet binds (_,body))
343 = let (xs,rhss) = case binds of AnnNonRec x rhs -> ([x],[rhs])
344 AnnRec xs_n_rhss -> unzip xs_n_rhss
347 fvss = map (fvsToEnv p' . fst) rhss
349 -- Sizes of free vars
350 sizes = map (\rhs_fvs -> sum (map idSizeW rhs_fvs)) fvss
352 -- the arity of each rhs
353 arities = map (length . fst . collect []) rhss
355 -- This p', d' defn is safe because all the items being pushed
356 -- are ptrs, so all have size 1. d' and p' reflect the stack
357 -- after the closures have been allocated in the heap (but not
358 -- filled in), and pointers to them parked on the stack.
359 p' = addListToFM p (zipE xs (mkStackOffsets d (nOfThem n_binds 1)))
361 zipE = zipEqual "schemeE"
363 -- ToDo: don't build thunks for things with no free variables
364 build_thunk dd [] size bco off arity
365 = returnBc (PUSH_BCO bco `consOL` unitOL (mkap (off+size) size))
367 mkap | arity == 0 = MKAP
369 build_thunk dd (fv:fvs) size bco off arity = do
370 (push_code, pushed_szw) <- pushAtom dd p' (AnnVar fv)
371 more_push_code <- build_thunk (dd+pushed_szw) fvs size bco off arity
372 returnBc (push_code `appOL` more_push_code)
374 alloc_code = toOL (zipWith mkAlloc sizes arities)
375 where mkAlloc sz 0 = ALLOC_AP sz
376 mkAlloc sz arity = ALLOC_PAP arity sz
378 compile_bind d' fvs x rhs size arity off = do
379 bco <- schemeR fvs (x,rhs)
380 build_thunk d' fvs size bco off arity
383 [ compile_bind d' fvs x rhs size arity n
384 | (fvs, x, rhs, size, arity, n) <-
385 zip6 fvss xs rhss sizes arities [n_binds, n_binds-1 .. 1]
388 body_code <- schemeE d' s p' body
389 thunk_codes <- sequence compile_binds
390 returnBc (alloc_code `appOL` concatOL thunk_codes `appOL` body_code)
394 schemeE d s p (AnnCase scrut bndr _ [(DataAlt dc, [bind1, bind2], rhs)])
395 | isUnboxedTupleCon dc, VoidArg <- typeCgRep (idType bind1)
397 -- case .... of x { (# VoidArg'd-thing, a #) -> ... }
399 -- case .... of a { DEFAULT -> ... }
400 -- becuse the return convention for both are identical.
402 -- Note that it does not matter losing the void-rep thing from the
403 -- envt (it won't be bound now) because we never look such things up.
405 = --trace "automagic mashing of case alts (# VoidArg, a #)" $
406 doCase d s p scrut bind2 [(DEFAULT, [], rhs)] True{-unboxed tuple-}
408 | isUnboxedTupleCon dc, VoidArg <- typeCgRep (idType bind2)
409 = --trace "automagic mashing of case alts (# a, VoidArg #)" $
410 doCase d s p scrut bind1 [(DEFAULT, [], rhs)] True{-unboxed tuple-}
412 schemeE d s p (AnnCase scrut bndr _ [(DataAlt dc, [bind1], rhs)])
413 | isUnboxedTupleCon dc
414 -- Similarly, convert
415 -- case .... of x { (# a #) -> ... }
417 -- case .... of a { DEFAULT -> ... }
418 = --trace "automagic mashing of case alts (# a #)" $
419 doCase d s p scrut bind1 [(DEFAULT, [], rhs)] True{-unboxed tuple-}
421 schemeE d s p (AnnCase scrut bndr _ alts)
422 = doCase d s p scrut bndr alts False{-not an unboxed tuple-}
424 schemeE d s p (AnnNote note (_, body))
427 schemeE d s p (AnnCast (_, body) _)
430 -- XXX - audreyt - After FC landed, this case of explicit eta-reduction
431 -- seems needed to make "data D = D deriving Typeable" work in GHCi.
432 -- however, how did AnnLam with a var (LocalId) survive until this place?
433 schemeE d s p (AnnLam var (_, AnnApp (_, body) (_, AnnVar inner)))
438 = pprPanic "ByteCodeGen.schemeE: unhandled case"
439 (pprCoreExpr (deAnnotate' other))
442 -- Compile code to do a tail call. Specifically, push the fn,
443 -- slide the on-stack app back down to the sequel depth,
444 -- and enter. Four cases:
447 -- An application "GHC.Prim.tagToEnum# <type> unboxed-int".
448 -- The int will be on the stack. Generate a code sequence
449 -- to convert it to the relevant constructor, SLIDE and ENTER.
451 -- 1. The fn denotes a ccall. Defer to generateCCall.
453 -- 2. (Another nasty hack). Spot (# a::VoidArg, b #) and treat
454 -- it simply as b -- since the representations are identical
455 -- (the VoidArg takes up zero stack space). Also, spot
456 -- (# b #) and treat it as b.
458 -- 3. Application of a constructor, by defn saturated.
459 -- Split the args into ptrs and non-ptrs, and push the nonptrs,
460 -- then the ptrs, and then do PACK and RETURN.
462 -- 4. Otherwise, it must be a function call. Push the args
463 -- right to left, SLIDE and ENTER.
465 schemeT :: Int -- Stack depth
466 -> Sequel -- Sequel depth
467 -> BCEnv -- stack env
468 -> AnnExpr' Id VarSet
473 -- | trace ("schemeT: env in = \n" ++ showSDocDebug (ppBCEnv p)) False
474 -- = panic "schemeT ?!?!"
476 -- | trace ("\nschemeT\n" ++ showSDoc (pprCoreExpr (deAnnotate' app)) ++ "\n") False
480 | Just (arg, constr_names) <- maybe_is_tagToEnum_call
481 = pushAtom d p arg `thenBc` \ (push, arg_words) ->
482 implement_tagToId constr_names `thenBc` \ tagToId_sequence ->
483 returnBc (push `appOL` tagToId_sequence
484 `appOL` mkSLIDE 1 (d+arg_words-s)
488 | Just (CCall ccall_spec) <- isFCallId_maybe fn
489 = generateCCall d s p ccall_spec fn args_r_to_l
491 -- Case 2: Constructor application
492 | Just con <- maybe_saturated_dcon,
493 isUnboxedTupleCon con
494 = case args_r_to_l of
495 [arg1,arg2] | isVoidArgAtom arg1 ->
496 unboxedTupleReturn d s p arg2
497 [arg1,arg2] | isVoidArgAtom arg2 ->
498 unboxedTupleReturn d s p arg1
499 _other -> unboxedTupleException
501 -- Case 3: Ordinary data constructor
502 | Just con <- maybe_saturated_dcon
503 = mkConAppCode d s p con args_r_to_l `thenBc` \ alloc_con ->
504 returnBc (alloc_con `appOL`
505 mkSLIDE 1 (d - s) `snocOL`
508 -- Case 4: Tail call of function
510 = doTailCall d s p fn args_r_to_l
513 -- Detect and extract relevant info for the tagToEnum kludge.
514 maybe_is_tagToEnum_call
515 = let extract_constr_Names ty
516 | Just (tyc, []) <- splitTyConApp_maybe (repType ty),
518 = map (getName . dataConWorkId) (tyConDataCons tyc)
519 -- NOTE: use the worker name, not the source name of
520 -- the DataCon. See DataCon.lhs for details.
522 = panic "maybe_is_tagToEnum_call.extract_constr_Ids"
525 (AnnApp (_, AnnApp (_, AnnVar v) (_, AnnType t)) arg)
526 -> case isPrimOpId_maybe v of
527 Just TagToEnumOp -> Just (snd arg, extract_constr_Names t)
531 -- Extract the args (R->L) and fn
532 -- The function will necessarily be a variable,
533 -- because we are compiling a tail call
534 (AnnVar fn, args_r_to_l) = splitApp app
536 -- Only consider this to be a constructor application iff it is
537 -- saturated. Otherwise, we'll call the constructor wrapper.
538 n_args = length args_r_to_l
540 = case isDataConWorkId_maybe fn of
541 Just con | dataConRepArity con == n_args -> Just con
544 -- -----------------------------------------------------------------------------
545 -- Generate code to build a constructor application,
546 -- leaving it on top of the stack
548 mkConAppCode :: Int -> Sequel -> BCEnv
549 -> DataCon -- The data constructor
550 -> [AnnExpr' Id VarSet] -- Args, in *reverse* order
553 mkConAppCode orig_d s p con [] -- Nullary constructor
554 = ASSERT( isNullaryRepDataCon con )
555 returnBc (unitOL (PUSH_G (getName (dataConWorkId con))))
556 -- Instead of doing a PACK, which would allocate a fresh
557 -- copy of this constructor, use the single shared version.
559 mkConAppCode orig_d s p con args_r_to_l
560 = ASSERT( dataConRepArity con == length args_r_to_l )
561 do_pushery orig_d (non_ptr_args ++ ptr_args)
563 -- The args are already in reverse order, which is the way PACK
564 -- expects them to be. We must push the non-ptrs after the ptrs.
565 (ptr_args, non_ptr_args) = partition isPtrAtom args_r_to_l
567 do_pushery d (arg:args)
568 = pushAtom d p arg `thenBc` \ (push, arg_words) ->
569 do_pushery (d+arg_words) args `thenBc` \ more_push_code ->
570 returnBc (push `appOL` more_push_code)
572 = returnBc (unitOL (PACK con n_arg_words))
574 n_arg_words = d - orig_d
577 -- -----------------------------------------------------------------------------
578 -- Returning an unboxed tuple with one non-void component (the only
579 -- case we can handle).
581 -- Remember, we don't want to *evaluate* the component that is being
582 -- returned, even if it is a pointed type. We always just return.
585 :: Int -> Sequel -> BCEnv
586 -> AnnExpr' Id VarSet -> BcM BCInstrList
587 unboxedTupleReturn d s p arg = do
588 (push, sz) <- pushAtom d p arg
589 returnBc (push `appOL`
590 mkSLIDE sz (d-s) `snocOL`
591 RETURN_UBX (atomRep arg))
593 -- -----------------------------------------------------------------------------
594 -- Generate code for a tail-call
597 :: Int -> Sequel -> BCEnv
598 -> Id -> [AnnExpr' Id VarSet]
600 doTailCall init_d s p fn args
601 = do_pushes init_d args (map atomRep args)
603 do_pushes d [] reps = do
604 ASSERT( null reps ) return ()
605 (push_fn, sz) <- pushAtom d p (AnnVar fn)
606 ASSERT( sz == 1 ) return ()
607 returnBc (push_fn `appOL` (
608 mkSLIDE ((d-init_d) + 1) (init_d - s) `appOL`
610 do_pushes d args reps = do
611 let (push_apply, n, rest_of_reps) = findPushSeq reps
612 (these_args, rest_of_args) = splitAt n args
613 (next_d, push_code) <- push_seq d these_args
614 instrs <- do_pushes (next_d + 1) rest_of_args rest_of_reps
615 -- ^^^ for the PUSH_APPLY_ instruction
616 returnBc (push_code `appOL` (push_apply `consOL` instrs))
618 push_seq d [] = return (d, nilOL)
619 push_seq d (arg:args) = do
620 (push_code, sz) <- pushAtom d p arg
621 (final_d, more_push_code) <- push_seq (d+sz) args
622 return (final_d, push_code `appOL` more_push_code)
624 -- v. similar to CgStackery.findMatch, ToDo: merge
625 findPushSeq (PtrArg: PtrArg: PtrArg: PtrArg: PtrArg: PtrArg: rest)
626 = (PUSH_APPLY_PPPPPP, 6, rest)
627 findPushSeq (PtrArg: PtrArg: PtrArg: PtrArg: PtrArg: rest)
628 = (PUSH_APPLY_PPPPP, 5, rest)
629 findPushSeq (PtrArg: PtrArg: PtrArg: PtrArg: rest)
630 = (PUSH_APPLY_PPPP, 4, rest)
631 findPushSeq (PtrArg: PtrArg: PtrArg: rest)
632 = (PUSH_APPLY_PPP, 3, rest)
633 findPushSeq (PtrArg: PtrArg: rest)
634 = (PUSH_APPLY_PP, 2, rest)
635 findPushSeq (PtrArg: rest)
636 = (PUSH_APPLY_P, 1, rest)
637 findPushSeq (VoidArg: rest)
638 = (PUSH_APPLY_V, 1, rest)
639 findPushSeq (NonPtrArg: rest)
640 = (PUSH_APPLY_N, 1, rest)
641 findPushSeq (FloatArg: rest)
642 = (PUSH_APPLY_F, 1, rest)
643 findPushSeq (DoubleArg: rest)
644 = (PUSH_APPLY_D, 1, rest)
645 findPushSeq (LongArg: rest)
646 = (PUSH_APPLY_L, 1, rest)
648 = panic "ByteCodeGen.findPushSeq"
650 -- -----------------------------------------------------------------------------
653 doCase :: Int -> Sequel -> BCEnv
654 -> AnnExpr Id VarSet -> Id -> [AnnAlt Id VarSet]
655 -> Bool -- True <=> is an unboxed tuple case, don't enter the result
657 doCase d s p (_,scrut)
658 bndr alts is_unboxed_tuple
660 -- Top of stack is the return itbl, as usual.
661 -- underneath it is the pointer to the alt_code BCO.
662 -- When an alt is entered, it assumes the returned value is
663 -- on top of the itbl.
666 -- An unlifted value gets an extra info table pushed on top
667 -- when it is returned.
668 unlifted_itbl_sizeW | isAlgCase = 0
671 -- depth of stack after the return value has been pushed
672 d_bndr = d + ret_frame_sizeW + idSizeW bndr
674 -- depth of stack after the extra info table for an unboxed return
675 -- has been pushed, if any. This is the stack depth at the
677 d_alts = d_bndr + unlifted_itbl_sizeW
679 -- Env in which to compile the alts, not including
680 -- any vars bound by the alts themselves
681 p_alts = addToFM p bndr (d_bndr - 1)
683 bndr_ty = idType bndr
684 isAlgCase = not (isUnLiftedType bndr_ty) && not is_unboxed_tuple
686 -- given an alt, return a discr and code for it.
687 codeALt alt@(DEFAULT, _, (_,rhs))
688 = schemeE d_alts s p_alts rhs `thenBc` \ rhs_code ->
689 returnBc (NoDiscr, rhs_code)
690 codeAlt alt@(discr, bndrs, (_,rhs))
691 -- primitive or nullary constructor alt: no need to UNPACK
692 | null real_bndrs = do
693 rhs_code <- schemeE d_alts s p_alts rhs
694 returnBc (my_discr alt, rhs_code)
695 -- algebraic alt with some binders
696 | ASSERT(isAlgCase) otherwise =
698 (ptrs,nptrs) = partition (isFollowableArg.idCgRep) real_bndrs
699 ptr_sizes = map idSizeW ptrs
700 nptrs_sizes = map idSizeW nptrs
701 bind_sizes = ptr_sizes ++ nptrs_sizes
702 size = sum ptr_sizes + sum nptrs_sizes
703 -- the UNPACK instruction unpacks in reverse order...
704 p' = addListToFM p_alts
705 (zip (reverse (ptrs ++ nptrs))
706 (mkStackOffsets d_alts (reverse bind_sizes)))
708 rhs_code <- schemeE (d_alts+size) s p' rhs
709 return (my_discr alt, unitOL (UNPACK size) `appOL` rhs_code)
711 real_bndrs = filter (not.isTyVar) bndrs
714 my_discr (DEFAULT, binds, rhs) = NoDiscr {-shouldn't really happen-}
715 my_discr (DataAlt dc, binds, rhs)
716 | isUnboxedTupleCon dc
717 = unboxedTupleException
719 = DiscrP (dataConTag dc - fIRST_TAG)
720 my_discr (LitAlt l, binds, rhs)
721 = case l of MachInt i -> DiscrI (fromInteger i)
722 MachFloat r -> DiscrF (fromRational r)
723 MachDouble r -> DiscrD (fromRational r)
724 MachChar i -> DiscrI (ord i)
725 _ -> pprPanic "schemeE(AnnCase).my_discr" (ppr l)
728 | not isAlgCase = Nothing
730 = case [dc | (DataAlt dc, _, _) <- alts] of
732 (dc:_) -> Just (tyConFamilySize (dataConTyCon dc))
734 -- the bitmap is relative to stack depth d, i.e. before the
735 -- BCO, info table and return value are pushed on.
736 -- This bit of code is v. similar to buildLivenessMask in CgBindery,
737 -- except that here we build the bitmap from the known bindings of
738 -- things that are pointers, whereas in CgBindery the code builds the
739 -- bitmap from the free slots and unboxed bindings.
741 bitmap = intsToReverseBitmap d{-size-} (sortLe (<=) rel_slots)
744 rel_slots = concat (map spread binds)
746 | isFollowableArg (idCgRep id) = [ rel_offset ]
748 where rel_offset = d - offset - 1
751 alt_stuff <- mapM codeAlt alts
752 alt_final <- mkMultiBranch maybe_ncons alt_stuff
754 alt_bco_name = getName bndr
755 alt_bco = mkProtoBCO alt_bco_name alt_final (Left alts)
756 0{-no arity-} d{-bitmap size-} bitmap True{-is alts-}
758 -- trace ("case: bndr = " ++ showSDocDebug (ppr bndr) ++ "\ndepth = " ++ show d ++ "\nenv = \n" ++ showSDocDebug (ppBCEnv p) ++
759 -- "\n bitmap = " ++ show bitmap) $ do
760 scrut_code <- schemeE (d + ret_frame_sizeW) (d + ret_frame_sizeW) p scrut
761 alt_bco' <- emitBc alt_bco
763 | isAlgCase = PUSH_ALTS alt_bco'
764 | otherwise = PUSH_ALTS_UNLIFTED alt_bco' (typeCgRep bndr_ty)
765 returnBc (push_alts `consOL` scrut_code)
768 -- -----------------------------------------------------------------------------
769 -- Deal with a CCall.
771 -- Taggedly push the args onto the stack R->L,
772 -- deferencing ForeignObj#s and adjusting addrs to point to
773 -- payloads in Ptr/Byte arrays. Then, generate the marshalling
774 -- (machine) code for the ccall, and create bytecodes to call that and
775 -- then return in the right way.
777 generateCCall :: Int -> Sequel -- stack and sequel depths
779 -> CCallSpec -- where to call
780 -> Id -- of target, for type info
781 -> [AnnExpr' Id VarSet] -- args (atoms)
784 generateCCall d0 s p ccall_spec@(CCallSpec target cconv safety) fn args_r_to_l
787 addr_sizeW = cgRepSizeW NonPtrArg
789 -- Get the args on the stack, with tags and suitably
790 -- dereferenced for the CCall. For each arg, return the
791 -- depth to the first word of the bits for that arg, and the
792 -- CgRep of what was actually pushed.
794 pargs d [] = returnBc []
796 = let arg_ty = repType (exprType (deAnnotate' a))
798 in case splitTyConApp_maybe arg_ty of
799 -- Don't push the FO; instead push the Addr# it
802 | t == arrayPrimTyCon || t == mutableArrayPrimTyCon
803 -> pargs (d + addr_sizeW) az `thenBc` \ rest ->
804 parg_ArrayishRep arrPtrsHdrSize d p a
806 returnBc ((code,NonPtrArg):rest)
808 | t == byteArrayPrimTyCon || t == mutableByteArrayPrimTyCon
809 -> pargs (d + addr_sizeW) az `thenBc` \ rest ->
810 parg_ArrayishRep arrWordsHdrSize d p a
812 returnBc ((code,NonPtrArg):rest)
814 -- Default case: push taggedly, but otherwise intact.
816 -> pushAtom d p a `thenBc` \ (code_a, sz_a) ->
817 pargs (d+sz_a) az `thenBc` \ rest ->
818 returnBc ((code_a, atomRep a) : rest)
820 -- Do magic for Ptr/Byte arrays. Push a ptr to the array on
821 -- the stack but then advance it over the headers, so as to
822 -- point to the payload.
823 parg_ArrayishRep hdrSize d p a
824 = pushAtom d p a `thenBc` \ (push_fo, _) ->
825 -- The ptr points at the header. Advance it over the
826 -- header and then pretend this is an Addr#.
827 returnBc (push_fo `snocOL` SWIZZLE 0 hdrSize)
830 pargs d0 args_r_to_l `thenBc` \ code_n_reps ->
832 (pushs_arg, a_reps_pushed_r_to_l) = unzip code_n_reps
834 push_args = concatOL pushs_arg
835 d_after_args = d0 + sum (map cgRepSizeW a_reps_pushed_r_to_l)
837 | null a_reps_pushed_r_to_l || head a_reps_pushed_r_to_l /= VoidArg
838 = panic "ByteCodeGen.generateCCall: missing or invalid World token?"
840 = reverse (tail a_reps_pushed_r_to_l)
842 -- Now: a_reps_pushed_RAW are the reps which are actually on the stack.
843 -- push_args is the code to do that.
844 -- d_after_args is the stack depth once the args are on.
846 -- Get the result rep.
847 (returns_void, r_rep)
848 = case maybe_getCCallReturnRep (idType fn) of
849 Nothing -> (True, VoidArg)
850 Just rr -> (False, rr)
852 Because the Haskell stack grows down, the a_reps refer to
853 lowest to highest addresses in that order. The args for the call
854 are on the stack. Now push an unboxed Addr# indicating
855 the C function to call. Then push a dummy placeholder for the
856 result. Finally, emit a CCALL insn with an offset pointing to the
857 Addr# just pushed, and a literal field holding the mallocville
858 address of the piece of marshalling code we generate.
859 So, just prior to the CCALL insn, the stack looks like this
860 (growing down, as usual):
865 Addr# address_of_C_fn
866 <placeholder-for-result#> (must be an unboxed type)
868 The interpreter then calls the marshall code mentioned
869 in the CCALL insn, passing it (& <placeholder-for-result#>),
870 that is, the addr of the topmost word in the stack.
871 When this returns, the placeholder will have been
872 filled in. The placeholder is slid down to the sequel
873 depth, and we RETURN.
875 This arrangement makes it simple to do f-i-dynamic since the Addr#
876 value is the first arg anyway.
878 The marshalling code is generated specifically for this
879 call site, and so knows exactly the (Haskell) stack
880 offsets of the args, fn address and placeholder. It
881 copies the args to the C stack, calls the stacked addr,
882 and parks the result back in the placeholder. The interpreter
883 calls it as a normal C call, assuming it has a signature
884 void marshall_code ( StgWord* ptr_to_top_of_stack )
886 -- resolve static address
890 -> returnBc (False, panic "ByteCodeGen.generateCCall(dyn)")
892 -> ioToBc (lookupStaticPtr target) `thenBc` \res ->
895 get_target_info `thenBc` \ (is_static, static_target_addr) ->
898 -- Get the arg reps, zapping the leading Addr# in the dynamic case
899 a_reps -- | trace (showSDoc (ppr a_reps_pushed_RAW)) False = error "???"
900 | is_static = a_reps_pushed_RAW
901 | otherwise = if null a_reps_pushed_RAW
902 then panic "ByteCodeGen.generateCCall: dyn with no args"
903 else tail a_reps_pushed_RAW
906 (push_Addr, d_after_Addr)
908 = (toOL [PUSH_UBX (Right static_target_addr) addr_sizeW],
909 d_after_args + addr_sizeW)
910 | otherwise -- is already on the stack
911 = (nilOL, d_after_args)
913 -- Push the return placeholder. For a call returning nothing,
914 -- this is a VoidArg (tag).
915 r_sizeW = cgRepSizeW r_rep
916 d_after_r = d_after_Addr + r_sizeW
917 r_lit = mkDummyLiteral r_rep
918 push_r = (if returns_void
920 else unitOL (PUSH_UBX (Left r_lit) r_sizeW))
922 -- generate the marshalling code we're going to call
925 arg1_offW = r_sizeW + addr_sizeW
926 args_offW = map (arg1_offW +)
927 (init (scanl (+) 0 (map cgRepSizeW a_reps)))
929 ioToBc (mkMarshalCode cconv
930 (r_offW, r_rep) addr_offW
931 (zip args_offW a_reps)) `thenBc` \ addr_of_marshaller ->
932 recordMallocBc addr_of_marshaller `thenBc_`
934 -- Offset of the next stack frame down the stack. The CCALL
935 -- instruction needs to describe the chunk of stack containing
936 -- the ccall args to the GC, so it needs to know how large it
937 -- is. See comment in Interpreter.c with the CCALL instruction.
938 stk_offset = d_after_r - s
941 do_call = unitOL (CCALL stk_offset (castPtr addr_of_marshaller))
943 wrapup = mkSLIDE r_sizeW (d_after_r - r_sizeW - s)
944 `snocOL` RETURN_UBX r_rep
946 --trace (show (arg1_offW, args_offW , (map cgRepSizeW a_reps) )) $
949 push_Addr `appOL` push_r `appOL` do_call `appOL` wrapup
953 -- Make a dummy literal, to be used as a placeholder for FFI return
954 -- values on the stack.
955 mkDummyLiteral :: CgRep -> Literal
958 NonPtrArg -> MachWord 0
959 DoubleArg -> MachDouble 0
960 FloatArg -> MachFloat 0
961 _ -> moan64 "mkDummyLiteral" (ppr pr)
965 -- GHC.Prim.Char# -> GHC.Prim.State# GHC.Prim.RealWorld
966 -- -> (# GHC.Prim.State# GHC.Prim.RealWorld, GHC.Prim.Int# #)
969 -- and check that an unboxed pair is returned wherein the first arg is VoidArg'd.
971 -- Alternatively, for call-targets returning nothing, convert
973 -- GHC.Prim.Char# -> GHC.Prim.State# GHC.Prim.RealWorld
974 -- -> (# GHC.Prim.State# GHC.Prim.RealWorld #)
978 maybe_getCCallReturnRep :: Type -> Maybe CgRep
979 maybe_getCCallReturnRep fn_ty
980 = let (a_tys, r_ty) = splitFunTys (dropForAlls fn_ty)
982 = if isSingleton r_reps then Nothing else Just (r_reps !! 1)
984 = case splitTyConApp_maybe (repType r_ty) of
985 (Just (tyc, tys)) -> (tyc, map typeCgRep tys)
987 ok = ( ( r_reps `lengthIs` 2 && VoidArg == head r_reps)
988 || r_reps == [VoidArg] )
989 && isUnboxedTupleTyCon r_tycon
990 && case maybe_r_rep_to_go of
992 Just r_rep -> r_rep /= PtrArg
993 -- if it was, it would be impossible
994 -- to create a valid return value
995 -- placeholder on the stack
996 blargh = pprPanic "maybe_getCCallReturn: can't handle:"
999 --trace (showSDoc (ppr (a_reps, r_reps))) $
1000 if ok then maybe_r_rep_to_go else blargh
1002 -- Compile code which expects an unboxed Int on the top of stack,
1003 -- (call it i), and pushes the i'th closure in the supplied list
1004 -- as a consequence.
1005 implement_tagToId :: [Name] -> BcM BCInstrList
1006 implement_tagToId names
1007 = ASSERT( notNull names )
1008 getLabelsBc (length names) `thenBc` \ labels ->
1009 getLabelBc `thenBc` \ label_fail ->
1010 getLabelBc `thenBc` \ label_exit ->
1011 zip4 labels (tail labels ++ [label_fail])
1012 [0 ..] names `bind` \ infos ->
1013 map (mkStep label_exit) infos `bind` \ steps ->
1014 returnBc (concatOL steps
1016 toOL [LABEL label_fail, CASEFAIL, LABEL label_exit])
1018 mkStep l_exit (my_label, next_label, n, name_for_n)
1019 = toOL [LABEL my_label,
1020 TESTEQ_I n next_label,
1025 -- -----------------------------------------------------------------------------
1028 -- Push an atom onto the stack, returning suitable code & number of
1029 -- stack words used.
1031 -- The env p must map each variable to the highest- numbered stack
1032 -- slot for it. For example, if the stack has depth 4 and we
1033 -- tagged-ly push (v :: Int#) on it, the value will be in stack[4],
1034 -- the tag in stack[5], the stack will have depth 6, and p must map v
1035 -- to 5 and not to 4. Stack locations are numbered from zero, so a
1036 -- depth 6 stack has valid words 0 .. 5.
1038 pushAtom :: Int -> BCEnv -> AnnExpr' Id VarSet -> BcM (BCInstrList, Int)
1040 pushAtom d p (AnnApp f (_, AnnType _))
1041 = pushAtom d p (snd f)
1043 pushAtom d p (AnnNote note e)
1044 = pushAtom d p (snd e)
1046 pushAtom d p (AnnLam x e)
1048 = pushAtom d p (snd e)
1050 pushAtom d p (AnnVar v)
1052 | idCgRep v == VoidArg
1053 = returnBc (nilOL, 0)
1056 = pprPanic "pushAtom: shouldn't get an FCallId here" (ppr v)
1058 | Just primop <- isPrimOpId_maybe v
1059 = returnBc (unitOL (PUSH_PRIMOP primop), 1)
1061 | Just d_v <- lookupBCEnv_maybe p v -- v is a local variable
1062 = returnBc (toOL (nOfThem sz (PUSH_L (d-d_v+sz-2))), sz)
1063 -- d - d_v the number of words between the TOS
1064 -- and the 1st slot of the object
1066 -- d - d_v - 1 the offset from the TOS of the 1st slot
1068 -- d - d_v - 1 + sz - 1 the offset from the TOS of the last slot
1071 -- Having found the last slot, we proceed to copy the right number of
1072 -- slots on to the top of the stack.
1074 | otherwise -- v must be a global variable
1076 returnBc (unitOL (PUSH_G (getName v)), sz)
1082 pushAtom d p (AnnLit lit)
1084 MachLabel fs _ -> code NonPtrArg
1085 MachWord w -> code NonPtrArg
1086 MachInt i -> code PtrArg
1087 MachFloat r -> code FloatArg
1088 MachDouble r -> code DoubleArg
1089 MachChar c -> code NonPtrArg
1090 MachStr s -> pushStr s
1093 = let size_host_words = cgRepSizeW rep
1094 in returnBc (unitOL (PUSH_UBX (Left lit) size_host_words),
1098 = let getMallocvilleAddr
1100 FastString _ n _ fp _ ->
1101 -- we could grab the Ptr from the ForeignPtr,
1102 -- but then we have no way to control its lifetime.
1103 -- In reality it'll probably stay alive long enoungh
1104 -- by virtue of the global FastString table, but
1105 -- to be on the safe side we copy the string into
1106 -- a malloc'd area of memory.
1107 ioToBc (mallocBytes (n+1)) `thenBc` \ ptr ->
1108 recordMallocBc ptr `thenBc_`
1110 withForeignPtr fp $ \p -> do
1111 memcpy ptr p (fromIntegral n)
1112 pokeByteOff ptr n (fromIntegral (ord '\0') :: Word8)
1116 getMallocvilleAddr `thenBc` \ addr ->
1117 -- Get the addr on the stack, untaggedly
1118 returnBc (unitOL (PUSH_UBX (Right addr) 1), 1)
1121 = pprPanic "ByteCodeGen.pushAtom"
1122 (pprCoreExpr (deAnnotate (undefined, other)))
1124 foreign import ccall unsafe "memcpy"
1125 memcpy :: Ptr a -> Ptr b -> CInt -> IO ()
1128 -- -----------------------------------------------------------------------------
1129 -- Given a bunch of alts code and their discrs, do the donkey work
1130 -- of making a multiway branch using a switch tree.
1131 -- What a load of hassle!
1133 mkMultiBranch :: Maybe Int -- # datacons in tycon, if alg alt
1134 -- a hint; generates better code
1135 -- Nothing is always safe
1136 -> [(Discr, BCInstrList)]
1138 mkMultiBranch maybe_ncons raw_ways
1139 = let d_way = filter (isNoDiscr.fst) raw_ways
1141 (\w1 w2 -> leAlt (fst w1) (fst w2))
1142 (filter (not.isNoDiscr.fst) raw_ways)
1144 mkTree :: [(Discr, BCInstrList)] -> Discr -> Discr -> BcM BCInstrList
1145 mkTree [] range_lo range_hi = returnBc the_default
1147 mkTree [val] range_lo range_hi
1148 | range_lo `eqAlt` range_hi
1149 = returnBc (snd val)
1151 = getLabelBc `thenBc` \ label_neq ->
1152 returnBc (mkTestEQ (fst val) label_neq
1154 `appOL` unitOL (LABEL label_neq)
1155 `appOL` the_default))
1157 mkTree vals range_lo range_hi
1158 = let n = length vals `div` 2
1159 vals_lo = take n vals
1160 vals_hi = drop n vals
1161 v_mid = fst (head vals_hi)
1163 getLabelBc `thenBc` \ label_geq ->
1164 mkTree vals_lo range_lo (dec v_mid) `thenBc` \ code_lo ->
1165 mkTree vals_hi v_mid range_hi `thenBc` \ code_hi ->
1166 returnBc (mkTestLT v_mid label_geq
1168 `appOL` unitOL (LABEL label_geq)
1172 = case d_way of [] -> unitOL CASEFAIL
1175 -- None of these will be needed if there are no non-default alts
1176 (mkTestLT, mkTestEQ, init_lo, init_hi)
1178 = panic "mkMultiBranch: awesome foursome"
1180 = case fst (head notd_ways) of {
1181 DiscrI _ -> ( \(DiscrI i) fail_label -> TESTLT_I i fail_label,
1182 \(DiscrI i) fail_label -> TESTEQ_I i fail_label,
1185 DiscrF _ -> ( \(DiscrF f) fail_label -> TESTLT_F f fail_label,
1186 \(DiscrF f) fail_label -> TESTEQ_F f fail_label,
1189 DiscrD _ -> ( \(DiscrD d) fail_label -> TESTLT_D d fail_label,
1190 \(DiscrD d) fail_label -> TESTEQ_D d fail_label,
1193 DiscrP _ -> ( \(DiscrP i) fail_label -> TESTLT_P i fail_label,
1194 \(DiscrP i) fail_label -> TESTEQ_P i fail_label,
1196 DiscrP algMaxBound )
1199 (algMinBound, algMaxBound)
1200 = case maybe_ncons of
1201 Just n -> (0, n - 1)
1202 Nothing -> (minBound, maxBound)
1204 (DiscrI i1) `eqAlt` (DiscrI i2) = i1 == i2
1205 (DiscrF f1) `eqAlt` (DiscrF f2) = f1 == f2
1206 (DiscrD d1) `eqAlt` (DiscrD d2) = d1 == d2
1207 (DiscrP i1) `eqAlt` (DiscrP i2) = i1 == i2
1208 NoDiscr `eqAlt` NoDiscr = True
1211 (DiscrI i1) `leAlt` (DiscrI i2) = i1 <= i2
1212 (DiscrF f1) `leAlt` (DiscrF f2) = f1 <= f2
1213 (DiscrD d1) `leAlt` (DiscrD d2) = d1 <= d2
1214 (DiscrP i1) `leAlt` (DiscrP i2) = i1 <= i2
1215 NoDiscr `leAlt` NoDiscr = True
1218 isNoDiscr NoDiscr = True
1221 dec (DiscrI i) = DiscrI (i-1)
1222 dec (DiscrP i) = DiscrP (i-1)
1223 dec other = other -- not really right, but if you
1224 -- do cases on floating values, you'll get what you deserve
1226 -- same snotty comment applies to the following
1228 minD, maxD :: Double
1234 mkTree notd_ways init_lo init_hi
1237 -- -----------------------------------------------------------------------------
1238 -- Supporting junk for the compilation schemes
1240 -- Describes case alts
1248 instance Outputable Discr where
1249 ppr (DiscrI i) = int i
1250 ppr (DiscrF f) = text (show f)
1251 ppr (DiscrD d) = text (show d)
1252 ppr (DiscrP i) = int i
1253 ppr NoDiscr = text "DEF"
1256 lookupBCEnv_maybe :: BCEnv -> Id -> Maybe Int
1257 lookupBCEnv_maybe = lookupFM
1259 idSizeW :: Id -> Int
1260 idSizeW id = cgRepSizeW (typeCgRep (idType id))
1262 unboxedTupleException :: a
1263 unboxedTupleException
1266 ("Bytecode generator can't handle unboxed tuples. Possibly due\n" ++
1267 "\tto foreign import/export decls in source. Workaround:\n" ++
1268 "\tcompile this module to a .o file, then restart session."))
1271 mkSLIDE n d = if d == 0 then nilOL else unitOL (SLIDE n d)
1274 splitApp :: AnnExpr' id ann -> (AnnExpr' id ann, [AnnExpr' id ann])
1275 -- The arguments are returned in *right-to-left* order
1276 splitApp (AnnApp (_,f) (_,a))
1277 | isTypeAtom a = splitApp f
1278 | otherwise = case splitApp f of
1279 (f', as) -> (f', a:as)
1280 splitApp (AnnNote n (_,e)) = splitApp e
1281 splitApp e = (e, [])
1284 isTypeAtom :: AnnExpr' id ann -> Bool
1285 isTypeAtom (AnnType _) = True
1286 isTypeAtom _ = False
1288 isVoidArgAtom :: AnnExpr' id ann -> Bool
1289 isVoidArgAtom (AnnVar v) = typeCgRep (idType v) == VoidArg
1290 isVoidArgAtom (AnnNote n (_,e)) = isVoidArgAtom e
1291 isVoidArgAtom _ = False
1293 atomRep :: AnnExpr' Id ann -> CgRep
1294 atomRep (AnnVar v) = typeCgRep (idType v)
1295 atomRep (AnnLit l) = typeCgRep (literalType l)
1296 atomRep (AnnNote n b) = atomRep (snd b)
1297 atomRep (AnnApp f (_, AnnType _)) = atomRep (snd f)
1298 atomRep (AnnLam x e) | isTyVar x = atomRep (snd e)
1299 atomRep other = pprPanic "atomRep" (ppr (deAnnotate (undefined,other)))
1301 isPtrAtom :: AnnExpr' Id ann -> Bool
1302 isPtrAtom e = atomRep e == PtrArg
1304 -- Let szsw be the sizes in words of some items pushed onto the stack,
1305 -- which has initial depth d'. Return the values which the stack environment
1306 -- should map these items to.
1307 mkStackOffsets :: Int -> [Int] -> [Int]
1308 mkStackOffsets original_depth szsw
1309 = map (subtract 1) (tail (scanl (+) original_depth szsw))
1311 -- -----------------------------------------------------------------------------
1312 -- The bytecode generator's monad
1316 nextlabel :: Int, -- for generating local labels
1317 malloced :: [Ptr ()] } -- ptrs malloced for current BCO
1318 -- Should be free()d when it is GCd
1320 newtype BcM r = BcM (BcM_State -> IO (BcM_State, r))
1322 ioToBc :: IO a -> BcM a
1323 ioToBc io = BcM $ \st -> do
1327 runBc :: BcM r -> IO (BcM_State, r)
1328 runBc (BcM m) = m (BcM_State 0 [])
1330 thenBc :: BcM a -> (a -> BcM b) -> BcM b
1331 thenBc (BcM expr) cont = BcM $ \st0 -> do
1332 (st1, q) <- expr st0
1337 thenBc_ :: BcM a -> BcM b -> BcM b
1338 thenBc_ (BcM expr) (BcM cont) = BcM $ \st0 -> do
1339 (st1, q) <- expr st0
1340 (st2, r) <- cont st1
1343 returnBc :: a -> BcM a
1344 returnBc result = BcM $ \st -> (return (st, result))
1346 instance Monad BcM where
1351 emitBc :: ([Ptr ()] -> ProtoBCO Name) -> BcM (ProtoBCO Name)
1353 = BcM $ \st -> return (st{malloced=[]}, bco (malloced st))
1355 recordMallocBc :: Ptr a -> BcM ()
1357 = BcM $ \st -> return (st{malloced = castPtr a : malloced st}, ())
1359 getLabelBc :: BcM Int
1361 = BcM $ \st -> return (st{nextlabel = 1 + nextlabel st}, nextlabel st)
1363 getLabelsBc :: Int -> BcM [Int]
1365 = BcM $ \st -> let ctr = nextlabel st
1366 in return (st{nextlabel = ctr+n}, [ctr .. ctr+n-1])