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))
428 = pprPanic "ByteCodeGen.schemeE: unhandled case"
429 (pprCoreExpr (deAnnotate' other))
432 -- Compile code to do a tail call. Specifically, push the fn,
433 -- slide the on-stack app back down to the sequel depth,
434 -- and enter. Four cases:
437 -- An application "GHC.Prim.tagToEnum# <type> unboxed-int".
438 -- The int will be on the stack. Generate a code sequence
439 -- to convert it to the relevant constructor, SLIDE and ENTER.
441 -- 1. The fn denotes a ccall. Defer to generateCCall.
443 -- 2. (Another nasty hack). Spot (# a::VoidArg, b #) and treat
444 -- it simply as b -- since the representations are identical
445 -- (the VoidArg takes up zero stack space). Also, spot
446 -- (# b #) and treat it as b.
448 -- 3. Application of a constructor, by defn saturated.
449 -- Split the args into ptrs and non-ptrs, and push the nonptrs,
450 -- then the ptrs, and then do PACK and RETURN.
452 -- 4. Otherwise, it must be a function call. Push the args
453 -- right to left, SLIDE and ENTER.
455 schemeT :: Int -- Stack depth
456 -> Sequel -- Sequel depth
457 -> BCEnv -- stack env
458 -> AnnExpr' Id VarSet
463 -- | trace ("schemeT: env in = \n" ++ showSDocDebug (ppBCEnv p)) False
464 -- = panic "schemeT ?!?!"
466 -- | trace ("\nschemeT\n" ++ showSDoc (pprCoreExpr (deAnnotate' app)) ++ "\n") False
470 | Just (arg, constr_names) <- maybe_is_tagToEnum_call
471 = pushAtom d p arg `thenBc` \ (push, arg_words) ->
472 implement_tagToId constr_names `thenBc` \ tagToId_sequence ->
473 returnBc (push `appOL` tagToId_sequence
474 `appOL` mkSLIDE 1 (d+arg_words-s)
478 | Just (CCall ccall_spec) <- isFCallId_maybe fn
479 = generateCCall d s p ccall_spec fn args_r_to_l
481 -- Case 2: Constructor application
482 | Just con <- maybe_saturated_dcon,
483 isUnboxedTupleCon con
484 = case args_r_to_l of
485 [arg1,arg2] | isVoidArgAtom arg1 ->
486 unboxedTupleReturn d s p arg2
487 [arg1,arg2] | isVoidArgAtom arg2 ->
488 unboxedTupleReturn d s p arg1
489 _other -> unboxedTupleException
491 -- Case 3: Ordinary data constructor
492 | Just con <- maybe_saturated_dcon
493 = mkConAppCode d s p con args_r_to_l `thenBc` \ alloc_con ->
494 returnBc (alloc_con `appOL`
495 mkSLIDE 1 (d - s) `snocOL`
498 -- Case 4: Tail call of function
500 = doTailCall d s p fn args_r_to_l
503 -- Detect and extract relevant info for the tagToEnum kludge.
504 maybe_is_tagToEnum_call
505 = let extract_constr_Names ty
506 | Just (tyc, []) <- splitTyConApp_maybe (repType ty),
508 = map (getName . dataConWorkId) (tyConDataCons tyc)
509 -- NOTE: use the worker name, not the source name of
510 -- the DataCon. See DataCon.lhs for details.
512 = panic "maybe_is_tagToEnum_call.extract_constr_Ids"
515 (AnnApp (_, AnnApp (_, AnnVar v) (_, AnnType t)) arg)
516 -> case isPrimOpId_maybe v of
517 Just TagToEnumOp -> Just (snd arg, extract_constr_Names t)
521 -- Extract the args (R->L) and fn
522 -- The function will necessarily be a variable,
523 -- because we are compiling a tail call
524 (AnnVar fn, args_r_to_l) = splitApp app
526 -- Only consider this to be a constructor application iff it is
527 -- saturated. Otherwise, we'll call the constructor wrapper.
528 n_args = length args_r_to_l
530 = case isDataConWorkId_maybe fn of
531 Just con | dataConRepArity con == n_args -> Just con
534 -- -----------------------------------------------------------------------------
535 -- Generate code to build a constructor application,
536 -- leaving it on top of the stack
538 mkConAppCode :: Int -> Sequel -> BCEnv
539 -> DataCon -- The data constructor
540 -> [AnnExpr' Id VarSet] -- Args, in *reverse* order
543 mkConAppCode orig_d s p con [] -- Nullary constructor
544 = ASSERT( isNullaryRepDataCon con )
545 returnBc (unitOL (PUSH_G (getName (dataConWorkId con))))
546 -- Instead of doing a PACK, which would allocate a fresh
547 -- copy of this constructor, use the single shared version.
549 mkConAppCode orig_d s p con args_r_to_l
550 = ASSERT( dataConRepArity con == length args_r_to_l )
551 do_pushery orig_d (non_ptr_args ++ ptr_args)
553 -- The args are already in reverse order, which is the way PACK
554 -- expects them to be. We must push the non-ptrs after the ptrs.
555 (ptr_args, non_ptr_args) = partition isPtrAtom args_r_to_l
557 do_pushery d (arg:args)
558 = pushAtom d p arg `thenBc` \ (push, arg_words) ->
559 do_pushery (d+arg_words) args `thenBc` \ more_push_code ->
560 returnBc (push `appOL` more_push_code)
562 = returnBc (unitOL (PACK con n_arg_words))
564 n_arg_words = d - orig_d
567 -- -----------------------------------------------------------------------------
568 -- Returning an unboxed tuple with one non-void component (the only
569 -- case we can handle).
571 -- Remember, we don't want to *evaluate* the component that is being
572 -- returned, even if it is a pointed type. We always just return.
575 :: Int -> Sequel -> BCEnv
576 -> AnnExpr' Id VarSet -> BcM BCInstrList
577 unboxedTupleReturn d s p arg = do
578 (push, sz) <- pushAtom d p arg
579 returnBc (push `appOL`
580 mkSLIDE sz (d-s) `snocOL`
581 RETURN_UBX (atomRep arg))
583 -- -----------------------------------------------------------------------------
584 -- Generate code for a tail-call
587 :: Int -> Sequel -> BCEnv
588 -> Id -> [AnnExpr' Id VarSet]
590 doTailCall init_d s p fn args
591 = do_pushes init_d args (map atomRep args)
593 do_pushes d [] reps = do
594 ASSERT( null reps ) return ()
595 (push_fn, sz) <- pushAtom d p (AnnVar fn)
596 ASSERT( sz == 1 ) return ()
597 returnBc (push_fn `appOL` (
598 mkSLIDE ((d-init_d) + 1) (init_d - s) `appOL`
600 do_pushes d args reps = do
601 let (push_apply, n, rest_of_reps) = findPushSeq reps
602 (these_args, rest_of_args) = splitAt n args
603 (next_d, push_code) <- push_seq d these_args
604 instrs <- do_pushes (next_d + 1) rest_of_args rest_of_reps
605 -- ^^^ for the PUSH_APPLY_ instruction
606 returnBc (push_code `appOL` (push_apply `consOL` instrs))
608 push_seq d [] = return (d, nilOL)
609 push_seq d (arg:args) = do
610 (push_code, sz) <- pushAtom d p arg
611 (final_d, more_push_code) <- push_seq (d+sz) args
612 return (final_d, push_code `appOL` more_push_code)
614 -- v. similar to CgStackery.findMatch, ToDo: merge
615 findPushSeq (PtrArg: PtrArg: PtrArg: PtrArg: PtrArg: PtrArg: rest)
616 = (PUSH_APPLY_PPPPPP, 6, rest)
617 findPushSeq (PtrArg: PtrArg: PtrArg: PtrArg: PtrArg: rest)
618 = (PUSH_APPLY_PPPPP, 5, rest)
619 findPushSeq (PtrArg: PtrArg: PtrArg: PtrArg: rest)
620 = (PUSH_APPLY_PPPP, 4, rest)
621 findPushSeq (PtrArg: PtrArg: PtrArg: rest)
622 = (PUSH_APPLY_PPP, 3, rest)
623 findPushSeq (PtrArg: PtrArg: rest)
624 = (PUSH_APPLY_PP, 2, rest)
625 findPushSeq (PtrArg: rest)
626 = (PUSH_APPLY_P, 1, rest)
627 findPushSeq (VoidArg: rest)
628 = (PUSH_APPLY_V, 1, rest)
629 findPushSeq (NonPtrArg: rest)
630 = (PUSH_APPLY_N, 1, rest)
631 findPushSeq (FloatArg: rest)
632 = (PUSH_APPLY_F, 1, rest)
633 findPushSeq (DoubleArg: rest)
634 = (PUSH_APPLY_D, 1, rest)
635 findPushSeq (LongArg: rest)
636 = (PUSH_APPLY_L, 1, rest)
638 = panic "ByteCodeGen.findPushSeq"
640 -- -----------------------------------------------------------------------------
643 doCase :: Int -> Sequel -> BCEnv
644 -> AnnExpr Id VarSet -> Id -> [AnnAlt Id VarSet]
645 -> Bool -- True <=> is an unboxed tuple case, don't enter the result
647 doCase d s p (_,scrut)
648 bndr alts is_unboxed_tuple
650 -- Top of stack is the return itbl, as usual.
651 -- underneath it is the pointer to the alt_code BCO.
652 -- When an alt is entered, it assumes the returned value is
653 -- on top of the itbl.
656 -- An unlifted value gets an extra info table pushed on top
657 -- when it is returned.
658 unlifted_itbl_sizeW | isAlgCase = 0
661 -- depth of stack after the return value has been pushed
662 d_bndr = d + ret_frame_sizeW + idSizeW bndr
664 -- depth of stack after the extra info table for an unboxed return
665 -- has been pushed, if any. This is the stack depth at the
667 d_alts = d_bndr + unlifted_itbl_sizeW
669 -- Env in which to compile the alts, not including
670 -- any vars bound by the alts themselves
671 p_alts = addToFM p bndr (d_bndr - 1)
673 bndr_ty = idType bndr
674 isAlgCase = not (isUnLiftedType bndr_ty) && not is_unboxed_tuple
676 -- given an alt, return a discr and code for it.
677 codeALt alt@(DEFAULT, _, (_,rhs))
678 = schemeE d_alts s p_alts rhs `thenBc` \ rhs_code ->
679 returnBc (NoDiscr, rhs_code)
680 codeAlt alt@(discr, bndrs, (_,rhs))
681 -- primitive or nullary constructor alt: no need to UNPACK
682 | null real_bndrs = do
683 rhs_code <- schemeE d_alts s p_alts rhs
684 returnBc (my_discr alt, rhs_code)
685 -- algebraic alt with some binders
686 | ASSERT(isAlgCase) otherwise =
688 (ptrs,nptrs) = partition (isFollowableArg.idCgRep) real_bndrs
689 ptr_sizes = map idSizeW ptrs
690 nptrs_sizes = map idSizeW nptrs
691 bind_sizes = ptr_sizes ++ nptrs_sizes
692 size = sum ptr_sizes + sum nptrs_sizes
693 -- the UNPACK instruction unpacks in reverse order...
694 p' = addListToFM p_alts
695 (zip (reverse (ptrs ++ nptrs))
696 (mkStackOffsets d_alts (reverse bind_sizes)))
698 rhs_code <- schemeE (d_alts+size) s p' rhs
699 return (my_discr alt, unitOL (UNPACK size) `appOL` rhs_code)
701 real_bndrs = filter (not.isTyVar) bndrs
704 my_discr (DEFAULT, binds, rhs) = NoDiscr {-shouldn't really happen-}
705 my_discr (DataAlt dc, binds, rhs)
706 | isUnboxedTupleCon dc
707 = unboxedTupleException
709 = DiscrP (dataConTag dc - fIRST_TAG)
710 my_discr (LitAlt l, binds, rhs)
711 = case l of MachInt i -> DiscrI (fromInteger i)
712 MachFloat r -> DiscrF (fromRational r)
713 MachDouble r -> DiscrD (fromRational r)
714 MachChar i -> DiscrI (ord i)
715 _ -> pprPanic "schemeE(AnnCase).my_discr" (ppr l)
718 | not isAlgCase = Nothing
720 = case [dc | (DataAlt dc, _, _) <- alts] of
722 (dc:_) -> Just (tyConFamilySize (dataConTyCon dc))
724 -- the bitmap is relative to stack depth d, i.e. before the
725 -- BCO, info table and return value are pushed on.
726 -- This bit of code is v. similar to buildLivenessMask in CgBindery,
727 -- except that here we build the bitmap from the known bindings of
728 -- things that are pointers, whereas in CgBindery the code builds the
729 -- bitmap from the free slots and unboxed bindings.
731 bitmap = intsToReverseBitmap d{-size-} (sortLe (<=) rel_slots)
734 rel_slots = concat (map spread binds)
736 | isFollowableArg (idCgRep id) = [ rel_offset ]
738 where rel_offset = d - offset - 1
741 alt_stuff <- mapM codeAlt alts
742 alt_final <- mkMultiBranch maybe_ncons alt_stuff
744 alt_bco_name = getName bndr
745 alt_bco = mkProtoBCO alt_bco_name alt_final (Left alts)
746 0{-no arity-} d{-bitmap size-} bitmap True{-is alts-}
748 -- trace ("case: bndr = " ++ showSDocDebug (ppr bndr) ++ "\ndepth = " ++ show d ++ "\nenv = \n" ++ showSDocDebug (ppBCEnv p) ++
749 -- "\n bitmap = " ++ show bitmap) $ do
750 scrut_code <- schemeE (d + ret_frame_sizeW) (d + ret_frame_sizeW) p scrut
751 alt_bco' <- emitBc alt_bco
753 | isAlgCase = PUSH_ALTS alt_bco'
754 | otherwise = PUSH_ALTS_UNLIFTED alt_bco' (typeCgRep bndr_ty)
755 returnBc (push_alts `consOL` scrut_code)
758 -- -----------------------------------------------------------------------------
759 -- Deal with a CCall.
761 -- Taggedly push the args onto the stack R->L,
762 -- deferencing ForeignObj#s and adjusting addrs to point to
763 -- payloads in Ptr/Byte arrays. Then, generate the marshalling
764 -- (machine) code for the ccall, and create bytecodes to call that and
765 -- then return in the right way.
767 generateCCall :: Int -> Sequel -- stack and sequel depths
769 -> CCallSpec -- where to call
770 -> Id -- of target, for type info
771 -> [AnnExpr' Id VarSet] -- args (atoms)
774 generateCCall d0 s p ccall_spec@(CCallSpec target cconv safety) fn args_r_to_l
777 addr_sizeW = cgRepSizeW NonPtrArg
779 -- Get the args on the stack, with tags and suitably
780 -- dereferenced for the CCall. For each arg, return the
781 -- depth to the first word of the bits for that arg, and the
782 -- CgRep of what was actually pushed.
784 pargs d [] = returnBc []
786 = let arg_ty = repType (exprType (deAnnotate' a))
788 in case splitTyConApp_maybe arg_ty of
789 -- Don't push the FO; instead push the Addr# it
792 | t == arrayPrimTyCon || t == mutableArrayPrimTyCon
793 -> pargs (d + addr_sizeW) az `thenBc` \ rest ->
794 parg_ArrayishRep arrPtrsHdrSize d p a
796 returnBc ((code,NonPtrArg):rest)
798 | t == byteArrayPrimTyCon || t == mutableByteArrayPrimTyCon
799 -> pargs (d + addr_sizeW) az `thenBc` \ rest ->
800 parg_ArrayishRep arrWordsHdrSize d p a
802 returnBc ((code,NonPtrArg):rest)
804 -- Default case: push taggedly, but otherwise intact.
806 -> pushAtom d p a `thenBc` \ (code_a, sz_a) ->
807 pargs (d+sz_a) az `thenBc` \ rest ->
808 returnBc ((code_a, atomRep a) : rest)
810 -- Do magic for Ptr/Byte arrays. Push a ptr to the array on
811 -- the stack but then advance it over the headers, so as to
812 -- point to the payload.
813 parg_ArrayishRep hdrSize d p a
814 = pushAtom d p a `thenBc` \ (push_fo, _) ->
815 -- The ptr points at the header. Advance it over the
816 -- header and then pretend this is an Addr#.
817 returnBc (push_fo `snocOL` SWIZZLE 0 hdrSize)
820 pargs d0 args_r_to_l `thenBc` \ code_n_reps ->
822 (pushs_arg, a_reps_pushed_r_to_l) = unzip code_n_reps
824 push_args = concatOL pushs_arg
825 d_after_args = d0 + sum (map cgRepSizeW a_reps_pushed_r_to_l)
827 | null a_reps_pushed_r_to_l || head a_reps_pushed_r_to_l /= VoidArg
828 = panic "ByteCodeGen.generateCCall: missing or invalid World token?"
830 = reverse (tail a_reps_pushed_r_to_l)
832 -- Now: a_reps_pushed_RAW are the reps which are actually on the stack.
833 -- push_args is the code to do that.
834 -- d_after_args is the stack depth once the args are on.
836 -- Get the result rep.
837 (returns_void, r_rep)
838 = case maybe_getCCallReturnRep (idType fn) of
839 Nothing -> (True, VoidArg)
840 Just rr -> (False, rr)
842 Because the Haskell stack grows down, the a_reps refer to
843 lowest to highest addresses in that order. The args for the call
844 are on the stack. Now push an unboxed Addr# indicating
845 the C function to call. Then push a dummy placeholder for the
846 result. Finally, emit a CCALL insn with an offset pointing to the
847 Addr# just pushed, and a literal field holding the mallocville
848 address of the piece of marshalling code we generate.
849 So, just prior to the CCALL insn, the stack looks like this
850 (growing down, as usual):
855 Addr# address_of_C_fn
856 <placeholder-for-result#> (must be an unboxed type)
858 The interpreter then calls the marshall code mentioned
859 in the CCALL insn, passing it (& <placeholder-for-result#>),
860 that is, the addr of the topmost word in the stack.
861 When this returns, the placeholder will have been
862 filled in. The placeholder is slid down to the sequel
863 depth, and we RETURN.
865 This arrangement makes it simple to do f-i-dynamic since the Addr#
866 value is the first arg anyway.
868 The marshalling code is generated specifically for this
869 call site, and so knows exactly the (Haskell) stack
870 offsets of the args, fn address and placeholder. It
871 copies the args to the C stack, calls the stacked addr,
872 and parks the result back in the placeholder. The interpreter
873 calls it as a normal C call, assuming it has a signature
874 void marshall_code ( StgWord* ptr_to_top_of_stack )
876 -- resolve static address
880 -> returnBc (False, panic "ByteCodeGen.generateCCall(dyn)")
882 -> ioToBc (lookupStaticPtr target) `thenBc` \res ->
885 get_target_info `thenBc` \ (is_static, static_target_addr) ->
888 -- Get the arg reps, zapping the leading Addr# in the dynamic case
889 a_reps -- | trace (showSDoc (ppr a_reps_pushed_RAW)) False = error "???"
890 | is_static = a_reps_pushed_RAW
891 | otherwise = if null a_reps_pushed_RAW
892 then panic "ByteCodeGen.generateCCall: dyn with no args"
893 else tail a_reps_pushed_RAW
896 (push_Addr, d_after_Addr)
898 = (toOL [PUSH_UBX (Right static_target_addr) addr_sizeW],
899 d_after_args + addr_sizeW)
900 | otherwise -- is already on the stack
901 = (nilOL, d_after_args)
903 -- Push the return placeholder. For a call returning nothing,
904 -- this is a VoidArg (tag).
905 r_sizeW = cgRepSizeW r_rep
906 d_after_r = d_after_Addr + r_sizeW
907 r_lit = mkDummyLiteral r_rep
908 push_r = (if returns_void
910 else unitOL (PUSH_UBX (Left r_lit) r_sizeW))
912 -- generate the marshalling code we're going to call
915 arg1_offW = r_sizeW + addr_sizeW
916 args_offW = map (arg1_offW +)
917 (init (scanl (+) 0 (map cgRepSizeW a_reps)))
919 ioToBc (mkMarshalCode cconv
920 (r_offW, r_rep) addr_offW
921 (zip args_offW a_reps)) `thenBc` \ addr_of_marshaller ->
922 recordMallocBc addr_of_marshaller `thenBc_`
924 -- Offset of the next stack frame down the stack. The CCALL
925 -- instruction needs to describe the chunk of stack containing
926 -- the ccall args to the GC, so it needs to know how large it
927 -- is. See comment in Interpreter.c with the CCALL instruction.
928 stk_offset = d_after_r - s
931 do_call = unitOL (CCALL stk_offset (castPtr addr_of_marshaller))
933 wrapup = mkSLIDE r_sizeW (d_after_r - r_sizeW - s)
934 `snocOL` RETURN_UBX r_rep
936 --trace (show (arg1_offW, args_offW , (map cgRepSizeW a_reps) )) $
939 push_Addr `appOL` push_r `appOL` do_call `appOL` wrapup
943 -- Make a dummy literal, to be used as a placeholder for FFI return
944 -- values on the stack.
945 mkDummyLiteral :: CgRep -> Literal
948 NonPtrArg -> MachWord 0
949 DoubleArg -> MachDouble 0
950 FloatArg -> MachFloat 0
951 _ -> moan64 "mkDummyLiteral" (ppr pr)
955 -- GHC.Prim.Char# -> GHC.Prim.State# GHC.Prim.RealWorld
956 -- -> (# GHC.Prim.State# GHC.Prim.RealWorld, GHC.Prim.Int# #)
959 -- and check that an unboxed pair is returned wherein the first arg is VoidArg'd.
961 -- Alternatively, for call-targets returning nothing, convert
963 -- GHC.Prim.Char# -> GHC.Prim.State# GHC.Prim.RealWorld
964 -- -> (# GHC.Prim.State# GHC.Prim.RealWorld #)
968 maybe_getCCallReturnRep :: Type -> Maybe CgRep
969 maybe_getCCallReturnRep fn_ty
970 = let (a_tys, r_ty) = splitFunTys (dropForAlls fn_ty)
972 = if isSingleton r_reps then Nothing else Just (r_reps !! 1)
974 = case splitTyConApp_maybe (repType r_ty) of
975 (Just (tyc, tys)) -> (tyc, map typeCgRep tys)
977 ok = ( ( r_reps `lengthIs` 2 && VoidArg == head r_reps)
978 || r_reps == [VoidArg] )
979 && isUnboxedTupleTyCon r_tycon
980 && case maybe_r_rep_to_go of
982 Just r_rep -> r_rep /= PtrArg
983 -- if it was, it would be impossible
984 -- to create a valid return value
985 -- placeholder on the stack
986 blargh = pprPanic "maybe_getCCallReturn: can't handle:"
989 --trace (showSDoc (ppr (a_reps, r_reps))) $
990 if ok then maybe_r_rep_to_go else blargh
992 -- Compile code which expects an unboxed Int on the top of stack,
993 -- (call it i), and pushes the i'th closure in the supplied list
995 implement_tagToId :: [Name] -> BcM BCInstrList
996 implement_tagToId names
997 = ASSERT( notNull names )
998 getLabelsBc (length names) `thenBc` \ labels ->
999 getLabelBc `thenBc` \ label_fail ->
1000 getLabelBc `thenBc` \ label_exit ->
1001 zip4 labels (tail labels ++ [label_fail])
1002 [0 ..] names `bind` \ infos ->
1003 map (mkStep label_exit) infos `bind` \ steps ->
1004 returnBc (concatOL steps
1006 toOL [LABEL label_fail, CASEFAIL, LABEL label_exit])
1008 mkStep l_exit (my_label, next_label, n, name_for_n)
1009 = toOL [LABEL my_label,
1010 TESTEQ_I n next_label,
1015 -- -----------------------------------------------------------------------------
1018 -- Push an atom onto the stack, returning suitable code & number of
1019 -- stack words used.
1021 -- The env p must map each variable to the highest- numbered stack
1022 -- slot for it. For example, if the stack has depth 4 and we
1023 -- tagged-ly push (v :: Int#) on it, the value will be in stack[4],
1024 -- the tag in stack[5], the stack will have depth 6, and p must map v
1025 -- to 5 and not to 4. Stack locations are numbered from zero, so a
1026 -- depth 6 stack has valid words 0 .. 5.
1028 pushAtom :: Int -> BCEnv -> AnnExpr' Id VarSet -> BcM (BCInstrList, Int)
1030 pushAtom d p (AnnApp f (_, AnnType _))
1031 = pushAtom d p (snd f)
1033 pushAtom d p (AnnNote note e)
1034 = pushAtom d p (snd e)
1036 pushAtom d p (AnnLam x e)
1038 = pushAtom d p (snd e)
1040 pushAtom d p (AnnVar v)
1042 | idCgRep v == VoidArg
1043 = returnBc (nilOL, 0)
1046 = pprPanic "pushAtom: shouldn't get an FCallId here" (ppr v)
1048 | Just primop <- isPrimOpId_maybe v
1049 = returnBc (unitOL (PUSH_PRIMOP primop), 1)
1051 | Just d_v <- lookupBCEnv_maybe p v -- v is a local variable
1052 = returnBc (toOL (nOfThem sz (PUSH_L (d-d_v+sz-2))), sz)
1053 -- d - d_v the number of words between the TOS
1054 -- and the 1st slot of the object
1056 -- d - d_v - 1 the offset from the TOS of the 1st slot
1058 -- d - d_v - 1 + sz - 1 the offset from the TOS of the last slot
1061 -- Having found the last slot, we proceed to copy the right number of
1062 -- slots on to the top of the stack.
1064 | otherwise -- v must be a global variable
1066 returnBc (unitOL (PUSH_G (getName v)), sz)
1072 pushAtom d p (AnnLit lit)
1074 MachLabel fs _ -> code NonPtrArg
1075 MachWord w -> code NonPtrArg
1076 MachInt i -> code PtrArg
1077 MachFloat r -> code FloatArg
1078 MachDouble r -> code DoubleArg
1079 MachChar c -> code NonPtrArg
1080 MachStr s -> pushStr s
1083 = let size_host_words = cgRepSizeW rep
1084 in returnBc (unitOL (PUSH_UBX (Left lit) size_host_words),
1088 = let getMallocvilleAddr
1090 FastString _ n _ fp _ ->
1091 -- we could grab the Ptr from the ForeignPtr,
1092 -- but then we have no way to control its lifetime.
1093 -- In reality it'll probably stay alive long enoungh
1094 -- by virtue of the global FastString table, but
1095 -- to be on the safe side we copy the string into
1096 -- a malloc'd area of memory.
1097 ioToBc (mallocBytes (n+1)) `thenBc` \ ptr ->
1098 recordMallocBc ptr `thenBc_`
1100 withForeignPtr fp $ \p -> do
1101 memcpy ptr p (fromIntegral n)
1102 pokeByteOff ptr n (fromIntegral (ord '\0') :: Word8)
1106 getMallocvilleAddr `thenBc` \ addr ->
1107 -- Get the addr on the stack, untaggedly
1108 returnBc (unitOL (PUSH_UBX (Right addr) 1), 1)
1111 = pprPanic "ByteCodeGen.pushAtom"
1112 (pprCoreExpr (deAnnotate (undefined, other)))
1114 foreign import ccall unsafe "memcpy"
1115 memcpy :: Ptr a -> Ptr b -> CInt -> IO ()
1118 -- -----------------------------------------------------------------------------
1119 -- Given a bunch of alts code and their discrs, do the donkey work
1120 -- of making a multiway branch using a switch tree.
1121 -- What a load of hassle!
1123 mkMultiBranch :: Maybe Int -- # datacons in tycon, if alg alt
1124 -- a hint; generates better code
1125 -- Nothing is always safe
1126 -> [(Discr, BCInstrList)]
1128 mkMultiBranch maybe_ncons raw_ways
1129 = let d_way = filter (isNoDiscr.fst) raw_ways
1131 (\w1 w2 -> leAlt (fst w1) (fst w2))
1132 (filter (not.isNoDiscr.fst) raw_ways)
1134 mkTree :: [(Discr, BCInstrList)] -> Discr -> Discr -> BcM BCInstrList
1135 mkTree [] range_lo range_hi = returnBc the_default
1137 mkTree [val] range_lo range_hi
1138 | range_lo `eqAlt` range_hi
1139 = returnBc (snd val)
1141 = getLabelBc `thenBc` \ label_neq ->
1142 returnBc (mkTestEQ (fst val) label_neq
1144 `appOL` unitOL (LABEL label_neq)
1145 `appOL` the_default))
1147 mkTree vals range_lo range_hi
1148 = let n = length vals `div` 2
1149 vals_lo = take n vals
1150 vals_hi = drop n vals
1151 v_mid = fst (head vals_hi)
1153 getLabelBc `thenBc` \ label_geq ->
1154 mkTree vals_lo range_lo (dec v_mid) `thenBc` \ code_lo ->
1155 mkTree vals_hi v_mid range_hi `thenBc` \ code_hi ->
1156 returnBc (mkTestLT v_mid label_geq
1158 `appOL` unitOL (LABEL label_geq)
1162 = case d_way of [] -> unitOL CASEFAIL
1165 -- None of these will be needed if there are no non-default alts
1166 (mkTestLT, mkTestEQ, init_lo, init_hi)
1168 = panic "mkMultiBranch: awesome foursome"
1170 = case fst (head notd_ways) of {
1171 DiscrI _ -> ( \(DiscrI i) fail_label -> TESTLT_I i fail_label,
1172 \(DiscrI i) fail_label -> TESTEQ_I i fail_label,
1175 DiscrF _ -> ( \(DiscrF f) fail_label -> TESTLT_F f fail_label,
1176 \(DiscrF f) fail_label -> TESTEQ_F f fail_label,
1179 DiscrD _ -> ( \(DiscrD d) fail_label -> TESTLT_D d fail_label,
1180 \(DiscrD d) fail_label -> TESTEQ_D d fail_label,
1183 DiscrP _ -> ( \(DiscrP i) fail_label -> TESTLT_P i fail_label,
1184 \(DiscrP i) fail_label -> TESTEQ_P i fail_label,
1186 DiscrP algMaxBound )
1189 (algMinBound, algMaxBound)
1190 = case maybe_ncons of
1191 Just n -> (0, n - 1)
1192 Nothing -> (minBound, maxBound)
1194 (DiscrI i1) `eqAlt` (DiscrI i2) = i1 == i2
1195 (DiscrF f1) `eqAlt` (DiscrF f2) = f1 == f2
1196 (DiscrD d1) `eqAlt` (DiscrD d2) = d1 == d2
1197 (DiscrP i1) `eqAlt` (DiscrP i2) = i1 == i2
1198 NoDiscr `eqAlt` NoDiscr = True
1201 (DiscrI i1) `leAlt` (DiscrI i2) = i1 <= i2
1202 (DiscrF f1) `leAlt` (DiscrF f2) = f1 <= f2
1203 (DiscrD d1) `leAlt` (DiscrD d2) = d1 <= d2
1204 (DiscrP i1) `leAlt` (DiscrP i2) = i1 <= i2
1205 NoDiscr `leAlt` NoDiscr = True
1208 isNoDiscr NoDiscr = True
1211 dec (DiscrI i) = DiscrI (i-1)
1212 dec (DiscrP i) = DiscrP (i-1)
1213 dec other = other -- not really right, but if you
1214 -- do cases on floating values, you'll get what you deserve
1216 -- same snotty comment applies to the following
1218 minD, maxD :: Double
1224 mkTree notd_ways init_lo init_hi
1227 -- -----------------------------------------------------------------------------
1228 -- Supporting junk for the compilation schemes
1230 -- Describes case alts
1238 instance Outputable Discr where
1239 ppr (DiscrI i) = int i
1240 ppr (DiscrF f) = text (show f)
1241 ppr (DiscrD d) = text (show d)
1242 ppr (DiscrP i) = int i
1243 ppr NoDiscr = text "DEF"
1246 lookupBCEnv_maybe :: BCEnv -> Id -> Maybe Int
1247 lookupBCEnv_maybe = lookupFM
1249 idSizeW :: Id -> Int
1250 idSizeW id = cgRepSizeW (typeCgRep (idType id))
1252 unboxedTupleException :: a
1253 unboxedTupleException
1256 ("Bytecode generator can't handle unboxed tuples. Possibly due\n" ++
1257 "\tto foreign import/export decls in source. Workaround:\n" ++
1258 "\tcompile this module to a .o file, then restart session."))
1261 mkSLIDE n d = if d == 0 then nilOL else unitOL (SLIDE n d)
1264 splitApp :: AnnExpr' id ann -> (AnnExpr' id ann, [AnnExpr' id ann])
1265 -- The arguments are returned in *right-to-left* order
1266 splitApp (AnnApp (_,f) (_,a))
1267 | isTypeAtom a = splitApp f
1268 | otherwise = case splitApp f of
1269 (f', as) -> (f', a:as)
1270 splitApp (AnnNote n (_,e)) = splitApp e
1271 splitApp e = (e, [])
1274 isTypeAtom :: AnnExpr' id ann -> Bool
1275 isTypeAtom (AnnType _) = True
1276 isTypeAtom _ = False
1278 isVoidArgAtom :: AnnExpr' id ann -> Bool
1279 isVoidArgAtom (AnnVar v) = typeCgRep (idType v) == VoidArg
1280 isVoidArgAtom (AnnNote n (_,e)) = isVoidArgAtom e
1281 isVoidArgAtom _ = False
1283 atomRep :: AnnExpr' Id ann -> CgRep
1284 atomRep (AnnVar v) = typeCgRep (idType v)
1285 atomRep (AnnLit l) = typeCgRep (literalType l)
1286 atomRep (AnnNote n b) = atomRep (snd b)
1287 atomRep (AnnApp f (_, AnnType _)) = atomRep (snd f)
1288 atomRep (AnnLam x e) | isTyVar x = atomRep (snd e)
1289 atomRep other = pprPanic "atomRep" (ppr (deAnnotate (undefined,other)))
1291 isPtrAtom :: AnnExpr' Id ann -> Bool
1292 isPtrAtom e = atomRep e == PtrArg
1294 -- Let szsw be the sizes in words of some items pushed onto the stack,
1295 -- which has initial depth d'. Return the values which the stack environment
1296 -- should map these items to.
1297 mkStackOffsets :: Int -> [Int] -> [Int]
1298 mkStackOffsets original_depth szsw
1299 = map (subtract 1) (tail (scanl (+) original_depth szsw))
1301 -- -----------------------------------------------------------------------------
1302 -- The bytecode generator's monad
1306 nextlabel :: Int, -- for generating local labels
1307 malloced :: [Ptr ()] } -- ptrs malloced for current BCO
1308 -- Should be free()d when it is GCd
1310 newtype BcM r = BcM (BcM_State -> IO (BcM_State, r))
1312 ioToBc :: IO a -> BcM a
1313 ioToBc io = BcM $ \st -> do
1317 runBc :: BcM r -> IO (BcM_State, r)
1318 runBc (BcM m) = m (BcM_State 0 [])
1320 thenBc :: BcM a -> (a -> BcM b) -> BcM b
1321 thenBc (BcM expr) cont = BcM $ \st0 -> do
1322 (st1, q) <- expr st0
1327 thenBc_ :: BcM a -> BcM b -> BcM b
1328 thenBc_ (BcM expr) (BcM cont) = BcM $ \st0 -> do
1329 (st1, q) <- expr st0
1330 (st2, r) <- cont st1
1333 returnBc :: a -> BcM a
1334 returnBc result = BcM $ \st -> (return (st, result))
1336 instance Monad BcM where
1341 emitBc :: ([Ptr ()] -> ProtoBCO Name) -> BcM (ProtoBCO Name)
1343 = BcM $ \st -> return (st{malloced=[]}, bco (malloced st))
1345 recordMallocBc :: Ptr a -> BcM ()
1347 = BcM $ \st -> return (st{malloced = castPtr a : malloced st}, ())
1349 getLabelBc :: BcM Int
1351 = BcM $ \st -> return (st{nextlabel = 1 + nextlabel st}, nextlabel st)
1353 getLabelsBc :: Int -> BcM [Int]
1355 = BcM $ \st -> let ctr = nextlabel st
1356 in return (st{nextlabel = ctr+n}, [ctr .. ctr+n-1])