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, mkSystemName )
21 import ForeignCall ( ForeignCall(..), CCallTarget(..), CCallSpec(..) )
22 import HscTypes ( ModGuts(..), ModGuts, typeEnvTyCons, typeEnvClasses )
23 import CoreUtils ( exprType )
25 import PprCore ( pprCoreExpr )
26 import Literal ( Literal(..), literalPrimRep )
28 import PrimOp ( PrimOp(..) )
29 import CoreFVs ( freeVars )
30 import Type ( typePrimRep, isUnLiftedType, splitTyConApp_maybe,
32 import DataCon ( DataCon, dataConTag, fIRST_TAG, dataConTyCon,
33 isUnboxedTupleCon, isNullaryDataCon,
35 import TyCon ( tyConFamilySize, isDataTyCon, tyConDataCons,
36 isFunTyCon, isUnboxedTupleTyCon )
37 import Class ( Class, classTyCon )
38 import Type ( Type, repType, splitFunTys, dropForAlls )
40 import DataCon ( dataConRepArity )
41 import Var ( isTyVar )
42 import VarSet ( VarSet, varSetElems )
43 import TysPrim ( foreignObjPrimTyCon,
44 arrayPrimTyCon, mutableArrayPrimTyCon,
45 byteArrayPrimTyCon, mutableByteArrayPrimTyCon
47 import PrimRep ( isFollowableRep )
48 import CmdLineOpts ( DynFlags, DynFlag(..) )
49 import ErrUtils ( showPass, dumpIfSet_dyn )
50 import Unique ( mkPseudoUnique3 )
51 import FastString ( FastString(..), unpackFS )
52 import Panic ( GhcException(..) )
53 import PprType ( pprType )
54 import SMRep ( arrWordsHdrSize, arrPtrsHdrSize )
56 import Constants ( wORD_SIZE )
57 import BasicTypes ( TopLevelFlag(..), isTopLevel, isNotTopLevel )
59 import Data.List ( intersperse, sortBy, zip4, zip5, partition )
60 import Foreign ( Ptr, castPtr, mallocBytes, pokeByteOff, Word8 )
61 import Foreign.C ( CInt )
62 import Control.Exception ( throwDyn )
64 import GHC.Exts ( Int(..), ByteArray# )
66 import Control.Monad ( when, mapAndUnzipM )
67 import Data.Char ( ord )
70 -- -----------------------------------------------------------------------------
71 -- Generating byte code for a complete module
73 byteCodeGen :: DynFlags
75 -> IO CompiledByteCode
76 byteCodeGen dflags (ModGuts { mg_binds = binds, mg_types = type_env })
77 = do showPass dflags "ByteCodeGen"
78 let local_tycons = typeEnvTyCons type_env
79 local_classes = typeEnvClasses type_env
80 tycs = local_tycons ++ map classTyCon local_classes
82 let flatBinds = [ (bndr, freeVars rhs)
83 | (bndr, rhs) <- flattenBinds binds]
85 (BcM_State final_ctr mallocd, proto_bcos)
86 <- runBc (mapM schemeTopBind flatBinds)
88 when (notNull mallocd)
89 (panic "ByteCodeGen.byteCodeGen: missing final emitBc?")
91 dumpIfSet_dyn dflags Opt_D_dump_BCOs
92 "Proto-BCOs" (vcat (intersperse (char ' ') (map ppr proto_bcos)))
94 assembleBCOs proto_bcos tycs
96 -- -----------------------------------------------------------------------------
97 -- Generating byte code for an expression
99 -- Returns: (the root BCO for this expression,
100 -- a list of auxilary BCOs resulting from compiling closures)
101 coreExprToBCOs :: DynFlags
104 coreExprToBCOs dflags expr
105 = do showPass dflags "ByteCodeGen"
107 -- create a totally bogus name for the top-level BCO; this
108 -- should be harmless, since it's never used for anything
109 let invented_name = mkSystemName (mkPseudoUnique3 0) FSLIT("ExprTopLevel")
110 invented_id = mkLocalId invented_name (panic "invented_id's type")
112 (BcM_State final_ctr mallocd, proto_bco)
113 <- runBc (schemeTopBind (invented_id, freeVars expr))
115 when (notNull mallocd)
116 (panic "ByteCodeGen.coreExprToBCOs: missing final emitBc?")
118 dumpIfSet_dyn dflags Opt_D_dump_BCOs "Proto-BCOs" (ppr proto_bco)
120 assembleBCO proto_bco
123 -- -----------------------------------------------------------------------------
124 -- Compilation schema for the bytecode generator
126 type BCInstrList = OrdList BCInstr
128 type Sequel = Int -- back off to this depth before ENTER
130 -- Maps Ids to the offset from the stack _base_ so we don't have
131 -- to mess with it after each push/pop.
132 type BCEnv = FiniteMap Id Int -- To find vars on the stack
134 ppBCEnv :: BCEnv -> SDoc
137 $$ nest 4 (vcat (map pp_one (sortBy cmp_snd (fmToList p))))
140 pp_one (var, offset) = int offset <> colon <+> ppr var <+> ppr (idPrimRep var)
141 cmp_snd x y = compare (snd x) (snd y)
143 -- Create a BCO and do a spot of peephole optimisation on the insns
148 -> Either [AnnAlt Id VarSet] (AnnExpr Id VarSet)
154 mkProtoBCO nm instrs_ordlist origin arity bitmap_size bitmap mallocd_blocks
157 protoBCOInstrs = maybe_with_stack_check,
158 protoBCOBitmap = bitmap,
159 protoBCOBitmapSize = bitmap_size,
160 protoBCOArity = arity,
161 protoBCOExpr = origin,
162 protoBCOPtrs = mallocd_blocks
165 -- Overestimate the stack usage (in words) of this BCO,
166 -- and if >= iNTERP_STACK_CHECK_THRESH, add an explicit
167 -- stack check. (The interpreter always does a stack check
168 -- for iNTERP_STACK_CHECK_THRESH words at the start of each
169 -- BCO anyway, so we only need to add an explicit on in the
170 -- (hopefully rare) cases when the (overestimated) stack use
171 -- exceeds iNTERP_STACK_CHECK_THRESH.
172 maybe_with_stack_check
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)
182 + 10 {- just to be really really sure -}
184 -- Merge local pushes
185 peep_d = peep (fromOL instrs_ordlist)
187 peep (PUSH_L off1 : PUSH_L off2 : PUSH_L off3 : rest)
188 = PUSH_LLL off1 (off2-1) (off3-2) : peep rest
189 peep (PUSH_L off1 : PUSH_L off2 : rest)
190 = PUSH_LL off1 (off2-1) : peep rest
196 argBits :: [PrimRep] -> [Bool]
199 | isFollowableRep rep = False : argBits args
200 | otherwise = take (getPrimRepSize rep) (repeat True) ++ argBits args
202 mkBitmap :: [Bool] -> [StgWord]
204 mkBitmap stuff = chunkToLiveness chunk : mkBitmap rest
205 where (chunk, rest) = splitAt wORD_SIZE_IN_BITS stuff
207 chunkToLiveness :: [Bool] -> StgWord
208 chunkToLiveness chunk =
209 foldr (.|.) 0 [ 1 `shiftL` n | (True,n) <- zip chunk [0..] ]
211 -- make a bitmap where the slots specified are the *zeros* in the bitmap.
212 -- eg. [1,2,4], size 4 ==> 0x8 (we leave any bits outside the size as zero,
213 -- just to make the bitmap easier to read).
214 intsToBitmap :: Int -> [Int] -> [StgWord]
215 intsToBitmap size slots{- must be sorted -}
218 (foldr xor init (map (1 `shiftL`) these)) :
219 intsToBitmap (size - wORD_SIZE_IN_BITS)
220 (map (\x -> x - wORD_SIZE_IN_BITS) rest)
221 where (these,rest) = span (<wORD_SIZE_IN_BITS) slots
223 | size >= wORD_SIZE_IN_BITS = complement 0
224 | otherwise = (1 `shiftL` size) - 1
226 wORD_SIZE_IN_BITS = wORD_SIZE * 8 :: Int
228 -- -----------------------------------------------------------------------------
231 -- Compile code for the right-hand side of a top-level binding
233 schemeTopBind :: (Id, AnnExpr Id VarSet) -> BcM (ProtoBCO Name)
236 schemeTopBind (id, rhs)
237 | Just data_con <- isDataConWrapId_maybe id,
238 isNullaryDataCon data_con
239 = -- Special case for the wrapper of a nullary data con.
240 -- It'll look like this: Nil = /\a -> $wNil a
241 -- If we feed it into schemeR, we'll get
243 -- because mkConAppCode treats nullary constructor applications
244 -- by just re-using the single top-level definition. So
245 -- for the wrapper itself, we must allocate it directly.
246 emitBc (mkProtoBCO (getName id) (toOL [PACK data_con 0, ENTER])
247 (Right rhs) 0 0 [{-no bitmap-}])
250 = schemeR [{- No free variables -}] (id, rhs)
252 -- -----------------------------------------------------------------------------
255 -- Compile code for a right-hand side, to give a BCO that,
256 -- when executed with the free variables and arguments on top of the stack,
257 -- will return with a pointer to the result on top of the stack, after
258 -- removing the free variables and arguments.
260 -- Park the resulting BCO in the monad. Also requires the
261 -- variable to which this value was bound, so as to give the
262 -- resulting BCO a name.
264 schemeR :: [Id] -- Free vars of the RHS, ordered as they
265 -- will appear in the thunk. Empty for
266 -- top-level things, which have no free vars.
267 -> (Id, AnnExpr Id VarSet)
268 -> BcM (ProtoBCO Name)
269 schemeR fvs (nm, rhs)
273 $$ (ppr.filter (not.isTyVar).varSetElems.fst) rhs
274 $$ pprCoreExpr (deAnnotate rhs)
280 = schemeR_wrk fvs nm rhs (collect [] rhs)
282 collect xs (_, AnnNote note e) = collect xs e
283 collect xs (_, AnnLam x e) = collect (if isTyVar x then xs else (x:xs)) e
284 collect xs (_, not_lambda) = (reverse xs, not_lambda)
286 schemeR_wrk fvs nm original_body (args, body)
288 all_args = reverse args ++ fvs
289 arity = length all_args
290 -- all_args are the args in reverse order. We're compiling a function
291 -- \fv1..fvn x1..xn -> e
292 -- i.e. the fvs come first
294 szsw_args = map idSizeW all_args
295 szw_args = sum szsw_args
296 p_init = listToFM (zip all_args (mkStackOffsets 0 szsw_args))
298 -- make the arg bitmap
299 bits = argBits (reverse (map idPrimRep all_args))
300 bitmap_size = length bits
301 bitmap = mkBitmap bits
303 schemeE szw_args 0 p_init body `thenBc` \ body_code ->
304 emitBc (mkProtoBCO (getName nm) body_code (Right original_body)
305 arity bitmap_size bitmap)
308 fvsToEnv :: BCEnv -> VarSet -> [Id]
309 -- Takes the free variables of a right-hand side, and
310 -- delivers an ordered list of the local variables that will
311 -- be captured in the thunk for the RHS
312 -- The BCEnv argument tells which variables are in the local
313 -- environment: these are the ones that should be captured
315 -- The code that constructs the thunk, and the code that executes
316 -- it, have to agree about this layout
317 fvsToEnv p fvs = [v | v <- varSetElems fvs,
318 isId v, -- Could be a type variable
321 -- -----------------------------------------------------------------------------
324 -- Compile code to apply the given expression to the remaining args
325 -- on the stack, returning a HNF.
326 schemeE :: Int -> Sequel -> BCEnv -> AnnExpr' Id VarSet -> BcM BCInstrList
328 -- Delegate tail-calls to schemeT.
329 schemeE d s p e@(AnnApp f a)
332 schemeE d s p e@(AnnVar v)
333 | not (isUnLiftedType v_type)
334 = -- Lifted-type thing; push it in the normal way
338 = -- Returning an unlifted value.
339 -- Heave it on the stack, SLIDE, and RETURN.
340 pushAtom d p (AnnVar v) `thenBc` \ (push, szw) ->
341 returnBc (push -- value onto stack
342 `appOL` mkSLIDE szw (d-s) -- clear to sequel
343 `snocOL` RETURN_UBX v_rep) -- go
346 v_rep = typePrimRep v_type
348 schemeE d s p (AnnLit literal)
349 = pushAtom d p (AnnLit literal) `thenBc` \ (push, szw) ->
350 let l_rep = literalPrimRep literal
351 in returnBc (push -- value onto stack
352 `appOL` mkSLIDE szw (d-s) -- clear to sequel
353 `snocOL` RETURN_UBX l_rep) -- go
356 schemeE d s p (AnnLet (AnnNonRec x (_,rhs)) (_,body))
357 | (AnnVar v, args_r_to_l) <- splitApp rhs,
358 Just data_con <- isDataConId_maybe v
359 = -- Special case for a non-recursive let whose RHS is a
360 -- (guaranteed saturatred) constructor application
361 -- Just allocate the constructor and carry on
362 mkConAppCode d s p data_con args_r_to_l `thenBc` \ alloc_code ->
363 schemeE (d+1) s (addToFM p x d) body `thenBc` \ body_code ->
364 returnBc (alloc_code `appOL` body_code)
366 -- General case for let. Generates correct, if inefficient, code in
368 schemeE d s p (AnnLet binds (_,body))
369 = let (xs,rhss) = case binds of AnnNonRec x rhs -> ([x],[rhs])
370 AnnRec xs_n_rhss -> unzip xs_n_rhss
373 fvss = map (fvsToEnv p' . fst) rhss
375 -- Sizes of free vars, + 1 for the fn
376 sizes = map (\rhs_fvs -> 1 + sum (map idSizeW rhs_fvs)) fvss
378 -- the arity of each rhs
379 arities = map (length . fst . collect []) rhss
381 -- This p', d' defn is safe because all the items being pushed
382 -- are ptrs, so all have size 1. d' and p' reflect the stack
383 -- after the closures have been allocated in the heap (but not
384 -- filled in), and pointers to them parked on the stack.
385 p' = addListToFM p (zipE xs (mkStackOffsets d (nOfThem n_binds 1)))
387 zipE = zipEqual "schemeE"
389 -- ToDo: don't build thunks for things with no free variables
390 build_thunk dd [] size bco off
391 = returnBc (PUSH_BCO bco
392 `consOL` unitOL (MKAP (off+size-1) size))
393 build_thunk dd (fv:fvs) size bco off = do
394 (push_code, pushed_szw) <- pushAtom dd p' (AnnVar fv)
395 more_push_code <- build_thunk (dd+pushed_szw) fvs size bco off
396 returnBc (push_code `appOL` more_push_code)
398 alloc_code = toOL (zipWith mkAlloc sizes arities)
399 where mkAlloc sz 0 = ALLOC_AP sz
400 mkAlloc sz arity = ALLOC_PAP arity sz
402 compile_bind d' fvs x rhs size off = do
403 bco <- schemeR fvs (x,rhs)
404 build_thunk d' fvs size bco off
407 [ compile_bind d' fvs x rhs size n
408 | (fvs, x, rhs, size, n) <-
409 zip5 fvss xs rhss sizes [n_binds, n_binds-1 .. 1]
412 body_code <- schemeE d' s p' body
413 thunk_codes <- sequence compile_binds
414 returnBc (alloc_code `appOL` concatOL thunk_codes `appOL` body_code)
418 schemeE d s p (AnnCase scrut bndr [(DataAlt dc, [bind1, bind2], rhs)])
419 | isUnboxedTupleCon dc && VoidRep == typePrimRep (idType bind1)
421 -- case .... of x { (# VoidRep'd-thing, a #) -> ... }
423 -- case .... of a { DEFAULT -> ... }
424 -- becuse the return convention for both are identical.
426 -- Note that it does not matter losing the void-rep thing from the
427 -- envt (it won't be bound now) because we never look such things up.
429 = --trace "automagic mashing of case alts (# VoidRep, a #)" $
430 doCase d s p scrut bind2 [(DEFAULT, [], rhs)] True{-unboxed tuple-}
432 | isUnboxedTupleCon dc && VoidRep == typePrimRep (idType bind2)
433 = --trace "automagic mashing of case alts (# a, VoidRep #)" $
434 doCase d s p scrut bind1 [(DEFAULT, [], rhs)] True{-unboxed tuple-}
436 schemeE d s p (AnnCase scrut bndr [(DataAlt dc, [bind1], rhs)])
437 | isUnboxedTupleCon dc
438 -- Similarly, convert
439 -- case .... of x { (# a #) -> ... }
441 -- case .... of a { DEFAULT -> ... }
442 = --trace "automagic mashing of case alts (# a #)" $
443 doCase d s p scrut bind1 [(DEFAULT, [], rhs)] True{-unboxed tuple-}
445 schemeE d s p (AnnCase scrut bndr alts)
446 = doCase d s p scrut bndr alts False{-not an unboxed tuple-}
448 schemeE d s p (AnnNote note (_, body))
452 = pprPanic "ByteCodeGen.schemeE: unhandled case"
453 (pprCoreExpr (deAnnotate' other))
456 -- Compile code to do a tail call. Specifically, push the fn,
457 -- slide the on-stack app back down to the sequel depth,
458 -- and enter. Four cases:
461 -- An application "GHC.Prim.tagToEnum# <type> unboxed-int".
462 -- The int will be on the stack. Generate a code sequence
463 -- to convert it to the relevant constructor, SLIDE and ENTER.
465 -- 1. The fn denotes a ccall. Defer to generateCCall.
467 -- 2. (Another nasty hack). Spot (# a::VoidRep, b #) and treat
468 -- it simply as b -- since the representations are identical
469 -- (the VoidRep takes up zero stack space). Also, spot
470 -- (# b #) and treat it as b.
472 -- 3. Application of a constructor, by defn saturated.
473 -- Split the args into ptrs and non-ptrs, and push the nonptrs,
474 -- then the ptrs, and then do PACK and RETURN.
476 -- 4. Otherwise, it must be a function call. Push the args
477 -- right to left, SLIDE and ENTER.
479 schemeT :: Int -- Stack depth
480 -> Sequel -- Sequel depth
481 -> BCEnv -- stack env
482 -> AnnExpr' Id VarSet
487 -- | trace ("schemeT: env in = \n" ++ showSDocDebug (ppBCEnv p)) False
488 -- = panic "schemeT ?!?!"
490 -- | trace ("\nschemeT\n" ++ showSDoc (pprCoreExpr (deAnnotate' app)) ++ "\n") False
494 | Just (arg, constr_names) <- maybe_is_tagToEnum_call
495 = pushAtom d p arg `thenBc` \ (push, arg_words) ->
496 implement_tagToId constr_names `thenBc` \ tagToId_sequence ->
497 returnBc (push `appOL` tagToId_sequence
498 `appOL` mkSLIDE 1 (d+arg_words-s)
502 | Just (CCall ccall_spec) <- isFCallId_maybe fn
503 = generateCCall d s p ccall_spec fn args_r_to_l
505 -- Case 2: Constructor application
506 | Just con <- maybe_dcon,
507 isUnboxedTupleCon con
508 = case args_r_to_l of
509 [arg1,arg2] | isVoidRepAtom arg1 ->
510 unboxedTupleReturn d s p arg2
511 [arg1,arg2] | isVoidRepAtom arg2 ->
512 unboxedTupleReturn d s p arg1
513 _other -> unboxedTupleException
515 -- Case 3: Ordinary data constructor
516 | Just con <- maybe_dcon
517 = mkConAppCode d s p con args_r_to_l `thenBc` \ alloc_con ->
518 returnBc (alloc_con `appOL`
519 mkSLIDE 1 (d - s) `snocOL`
522 -- Case 4: Tail call of function
524 = doTailCall d s p fn args_r_to_l
527 -- Detect and extract relevant info for the tagToEnum kludge.
528 maybe_is_tagToEnum_call
529 = let extract_constr_Names ty
530 = case splitTyConApp_maybe (repType ty) of
531 (Just (tyc, [])) | isDataTyCon tyc
532 -> map getName (tyConDataCons tyc)
533 other -> panic "maybe_is_tagToEnum_call.extract_constr_Ids"
536 (AnnApp (_, AnnApp (_, AnnVar v) (_, AnnType t)) arg)
537 -> case isPrimOpId_maybe v of
538 Just TagToEnumOp -> Just (snd arg, extract_constr_Names t)
542 -- Extract the args (R->L) and fn
543 -- The function will necessarily be a variable,
544 -- because we are compiling a tail call
545 (AnnVar fn, args_r_to_l) = splitApp app
546 n_args = length args_r_to_l
548 -- only consider this to be a constructor application iff it is
549 -- saturated. Otherwise, we'll call the constructor wrapper.
550 maybe_dcon = case isDataConId_maybe fn of
551 Just con | dataConRepArity con == n_args -> Just con
554 -- -----------------------------------------------------------------------------
555 -- Generate code to build a constructor application,
556 -- leaving it on top of the stack
558 mkConAppCode :: Int -> Sequel -> BCEnv
559 -> DataCon -- The data constructor
560 -> [AnnExpr' Id VarSet] -- Args, in *reverse* order
563 mkConAppCode orig_d s p con [] -- Nullary constructor
564 = ASSERT( isNullaryDataCon con )
565 returnBc (unitOL (PUSH_G (getName con)))
566 -- Instead of doing a PACK, which would allocate a fresh
567 -- copy of this constructor, use the single shared version.
568 -- The name of the constructor is the name of its wrapper function
570 mkConAppCode orig_d s p con args_r_to_l
571 = ASSERT( dataConRepArity con == length args_r_to_l )
572 do_pushery orig_d (non_ptr_args ++ ptr_args)
574 -- The args are already in reverse order, which is the way PACK
575 -- expects them to be. We must push the non-ptrs after the ptrs.
576 (ptr_args, non_ptr_args) = partition isPtrAtom args_r_to_l
578 do_pushery d (arg:args)
579 = pushAtom d p arg `thenBc` \ (push, arg_words) ->
580 do_pushery (d+arg_words) args `thenBc` \ more_push_code ->
581 returnBc (push `appOL` more_push_code)
583 = returnBc (unitOL (PACK con n_arg_words))
585 n_arg_words = d - orig_d
588 -- -----------------------------------------------------------------------------
589 -- Returning an unboxed tuple with one non-void component (the only
590 -- case we can handle).
592 -- Remember, we don't want to *evaluate* the component that is being
593 -- returned, even if it is a pointed type. We always just return.
596 :: Int -> Sequel -> BCEnv
597 -> AnnExpr' Id VarSet -> BcM BCInstrList
598 unboxedTupleReturn d s p arg = do
599 (push, sz) <- pushAtom d p arg
600 returnBc (push `appOL`
601 mkSLIDE sz (d-s) `snocOL`
602 RETURN_UBX (atomRep arg))
604 -- -----------------------------------------------------------------------------
605 -- Generate code for a tail-call
608 :: Int -> Sequel -> BCEnv
609 -> Id -> [AnnExpr' Id VarSet]
611 doTailCall init_d s p fn args
612 = do_pushes init_d args (map (primRepToArgRep.atomRep) args)
614 do_pushes d [] reps = do
616 (push_fn, sz) <- pushAtom d p (AnnVar fn)
618 returnBc (push_fn `appOL` (
619 mkSLIDE ((d-init_d) + 1) (init_d - s) `appOL`
621 do_pushes d args reps = do
622 let (push_apply, n, rest_of_reps) = findPushSeq reps
623 (these_args, rest_of_args) = splitAt n args
624 (next_d, push_code) <- push_seq d these_args
625 instrs <- do_pushes (next_d + 1) rest_of_args rest_of_reps
626 -- ^^^ for the PUSH_APPLY_ instruction
627 returnBc (push_code `appOL` (push_apply `consOL` instrs))
629 push_seq d [] = return (d, nilOL)
630 push_seq d (arg:args) = do
631 (push_code, sz) <- pushAtom d p arg
632 (final_d, more_push_code) <- push_seq (d+sz) args
633 return (final_d, push_code `appOL` more_push_code)
635 -- v. similar to CgStackery.findMatch, ToDo: merge
636 findPushSeq (RepP: RepP: RepP: RepP: RepP: RepP: RepP: rest)
637 = (PUSH_APPLY_PPPPPPP, 7, rest)
638 findPushSeq (RepP: RepP: RepP: RepP: RepP: RepP: rest)
639 = (PUSH_APPLY_PPPPPP, 6, rest)
640 findPushSeq (RepP: RepP: RepP: RepP: RepP: rest)
641 = (PUSH_APPLY_PPPPP, 5, rest)
642 findPushSeq (RepP: RepP: RepP: RepP: rest)
643 = (PUSH_APPLY_PPPP, 4, rest)
644 findPushSeq (RepP: RepP: RepP: rest)
645 = (PUSH_APPLY_PPP, 3, rest)
646 findPushSeq (RepP: RepP: rest)
647 = (PUSH_APPLY_PP, 2, rest)
648 findPushSeq (RepP: rest)
649 = (PUSH_APPLY_P, 1, rest)
650 findPushSeq (RepV: rest)
651 = (PUSH_APPLY_V, 1, rest)
652 findPushSeq (RepN: rest)
653 = (PUSH_APPLY_N, 1, rest)
654 findPushSeq (RepF: rest)
655 = (PUSH_APPLY_F, 1, rest)
656 findPushSeq (RepD: rest)
657 = (PUSH_APPLY_D, 1, rest)
658 findPushSeq (RepL: rest)
659 = (PUSH_APPLY_L, 1, rest)
661 = panic "ByteCodeGen.findPushSeq"
663 -- -----------------------------------------------------------------------------
666 doCase :: Int -> Sequel -> BCEnv
667 -> AnnExpr Id VarSet -> Id -> [AnnAlt Id VarSet]
668 -> Bool -- True <=> is an unboxed tuple case, don't enter the result
670 doCase d s p (_,scrut)
671 bndr alts is_unboxed_tuple
673 -- Top of stack is the return itbl, as usual.
674 -- underneath it is the pointer to the alt_code BCO.
675 -- When an alt is entered, it assumes the returned value is
676 -- on top of the itbl.
679 -- An unlifted value gets an extra info table pushed on top
680 -- when it is returned.
681 unlifted_itbl_sizeW | isAlgCase = 0
684 -- depth of stack after the return value has been pushed
685 d_bndr = d + ret_frame_sizeW + idSizeW bndr
687 -- depth of stack after the extra info table for an unboxed return
688 -- has been pushed, if any. This is the stack depth at the
690 d_alts = d_bndr + unlifted_itbl_sizeW
692 -- Env in which to compile the alts, not including
693 -- any vars bound by the alts themselves
694 p_alts = addToFM p bndr (d_bndr - 1)
696 bndr_ty = idType bndr
697 isAlgCase = not (isUnLiftedType bndr_ty) && not is_unboxed_tuple
699 -- given an alt, return a discr and code for it.
700 codeALt alt@(DEFAULT, _, (_,rhs))
701 = schemeE d_alts s p_alts rhs `thenBc` \ rhs_code ->
702 returnBc (NoDiscr, rhs_code)
703 codeAlt alt@(discr, bndrs, (_,rhs))
704 -- primitive or nullary constructor alt: no need to UNPACK
705 | null real_bndrs = do
706 rhs_code <- schemeE d_alts s p_alts rhs
707 returnBc (my_discr alt, rhs_code)
708 -- algebraic alt with some binders
709 | ASSERT(isAlgCase) otherwise =
711 (ptrs,nptrs) = partition (isFollowableRep.idPrimRep) real_bndrs
712 ptr_sizes = map idSizeW ptrs
713 nptrs_sizes = map idSizeW nptrs
714 bind_sizes = ptr_sizes ++ nptrs_sizes
715 size = sum ptr_sizes + sum nptrs_sizes
716 -- the UNPACK instruction unpacks in reverse order...
717 p' = addListToFM p_alts
718 (zip (reverse (ptrs ++ nptrs))
719 (mkStackOffsets d_alts (reverse bind_sizes)))
721 rhs_code <- schemeE (d_alts+size) s p' rhs
722 return (my_discr alt, unitOL (UNPACK size) `appOL` rhs_code)
724 real_bndrs = filter (not.isTyVar) bndrs
727 my_discr (DEFAULT, binds, rhs) = NoDiscr {-shouldn't really happen-}
728 my_discr (DataAlt dc, binds, rhs)
729 | isUnboxedTupleCon dc
730 = unboxedTupleException
732 = DiscrP (dataConTag dc - fIRST_TAG)
733 my_discr (LitAlt l, binds, rhs)
734 = case l of MachInt i -> DiscrI (fromInteger i)
735 MachFloat r -> DiscrF (fromRational r)
736 MachDouble r -> DiscrD (fromRational r)
737 MachChar i -> DiscrI i
738 _ -> pprPanic "schemeE(AnnCase).my_discr" (ppr l)
741 | not isAlgCase = Nothing
743 = case [dc | (DataAlt dc, _, _) <- alts] of
745 (dc:_) -> Just (tyConFamilySize (dataConTyCon dc))
747 -- the bitmap is relative to stack depth d, i.e. before the
748 -- BCO, info table and return value are pushed on.
749 -- This bit of code is v. similar to buildLivenessMask in CgBindery,
750 -- except that here we build the bitmap from the known bindings of
751 -- things that are pointers, whereas in CgBindery the code builds the
752 -- bitmap from the free slots and unboxed bindings.
754 bitmap = intsToBitmap d{-size-} (sortLt (<) rel_slots)
757 rel_slots = concat (map spread binds)
759 | isFollowableRep (idPrimRep id) = [ rel_offset ]
761 where rel_offset = d - offset - 1
764 alt_stuff <- mapM codeAlt alts
765 alt_final <- mkMultiBranch maybe_ncons alt_stuff
767 alt_bco_name = getName bndr
768 alt_bco = mkProtoBCO alt_bco_name alt_final (Left alts)
769 0{-no arity-} d{-bitmap size-} bitmap
771 -- trace ("case: bndr = " ++ showSDocDebug (ppr bndr) ++ "\ndepth = " ++ show d ++ "\nenv = \n" ++ showSDocDebug (ppBCEnv p) ++
772 -- "\n bitmap = " ++ show bitmap) $ do
773 scrut_code <- schemeE (d + ret_frame_sizeW) (d + ret_frame_sizeW) p scrut
774 alt_bco' <- emitBc alt_bco
776 | isAlgCase = PUSH_ALTS alt_bco'
777 | otherwise = PUSH_ALTS_UNLIFTED alt_bco' (typePrimRep bndr_ty)
778 returnBc (push_alts `consOL` scrut_code)
781 -- -----------------------------------------------------------------------------
782 -- Deal with a CCall.
784 -- Taggedly push the args onto the stack R->L,
785 -- deferencing ForeignObj#s and (ToDo: adjusting addrs to point to
786 -- payloads in Ptr/Byte arrays). Then, generate the marshalling
787 -- (machine) code for the ccall, and create bytecodes to call that and
788 -- then return in the right way.
790 generateCCall :: Int -> Sequel -- stack and sequel depths
792 -> CCallSpec -- where to call
793 -> Id -- of target, for type info
794 -> [AnnExpr' Id VarSet] -- args (atoms)
797 generateCCall d0 s p ccall_spec@(CCallSpec target cconv safety) fn args_r_to_l
800 addr_sizeW = getPrimRepSize AddrRep
802 -- Get the args on the stack, with tags and suitably
803 -- dereferenced for the CCall. For each arg, return the
804 -- depth to the first word of the bits for that arg, and the
805 -- PrimRep of what was actually pushed.
807 pargs d [] = returnBc []
809 = let arg_ty = repType (exprType (deAnnotate' a))
811 in case splitTyConApp_maybe arg_ty of
812 -- Don't push the FO; instead push the Addr# it
815 | t == arrayPrimTyCon || t == mutableArrayPrimTyCon
816 -> pargs (d + addr_sizeW) az `thenBc` \ rest ->
817 parg_ArrayishRep arrPtrsHdrSize d p a
819 returnBc ((code,AddrRep):rest)
821 | t == byteArrayPrimTyCon || t == mutableByteArrayPrimTyCon
822 -> pargs (d + addr_sizeW) az `thenBc` \ rest ->
823 parg_ArrayishRep arrWordsHdrSize d p a
825 returnBc ((code,AddrRep):rest)
827 -- Default case: push taggedly, but otherwise intact.
829 -> pushAtom d p a `thenBc` \ (code_a, sz_a) ->
830 pargs (d+sz_a) az `thenBc` \ rest ->
831 returnBc ((code_a, atomRep a) : rest)
833 -- Do magic for Ptr/Byte arrays. Push a ptr to the array on
834 -- the stack but then advance it over the headers, so as to
835 -- point to the payload.
836 parg_ArrayishRep hdrSizeW d p a
837 = pushAtom d p a `thenBc` \ (push_fo, _) ->
838 -- The ptr points at the header. Advance it over the
839 -- header and then pretend this is an Addr#.
840 returnBc (push_fo `snocOL`
841 SWIZZLE 0 (hdrSizeW * getPrimRepSize WordRep
845 pargs d0 args_r_to_l `thenBc` \ code_n_reps ->
847 (pushs_arg, a_reps_pushed_r_to_l) = unzip code_n_reps
849 push_args = concatOL pushs_arg
850 d_after_args = d0 + sum (map getPrimRepSize a_reps_pushed_r_to_l)
852 | null a_reps_pushed_r_to_l || head a_reps_pushed_r_to_l /= VoidRep
853 = panic "ByteCodeGen.generateCCall: missing or invalid World token?"
855 = reverse (tail a_reps_pushed_r_to_l)
857 -- Now: a_reps_pushed_RAW are the reps which are actually on the stack.
858 -- push_args is the code to do that.
859 -- d_after_args is the stack depth once the args are on.
861 -- Get the result rep.
862 (returns_void, r_rep)
863 = case maybe_getCCallReturnRep (idType fn) of
864 Nothing -> (True, VoidRep)
865 Just rr -> (False, rr)
867 Because the Haskell stack grows down, the a_reps refer to
868 lowest to highest addresses in that order. The args for the call
869 are on the stack. Now push an unboxed Addr# indicating
870 the C function to call. Then push a dummy placeholder for the
871 result. Finally, emit a CCALL insn with an offset pointing to the
872 Addr# just pushed, and a literal field holding the mallocville
873 address of the piece of marshalling code we generate.
874 So, just prior to the CCALL insn, the stack looks like this
875 (growing down, as usual):
880 Addr# address_of_C_fn
881 <placeholder-for-result#> (must be an unboxed type)
883 The interpreter then calls the marshall code mentioned
884 in the CCALL insn, passing it (& <placeholder-for-result#>),
885 that is, the addr of the topmost word in the stack.
886 When this returns, the placeholder will have been
887 filled in. The placeholder is slid down to the sequel
888 depth, and we RETURN.
890 This arrangement makes it simple to do f-i-dynamic since the Addr#
891 value is the first arg anyway.
893 The marshalling code is generated specifically for this
894 call site, and so knows exactly the (Haskell) stack
895 offsets of the args, fn address and placeholder. It
896 copies the args to the C stack, calls the stacked addr,
897 and parks the result back in the placeholder. The interpreter
898 calls it as a normal C call, assuming it has a signature
899 void marshall_code ( StgWord* ptr_to_top_of_stack )
901 -- resolve static address
905 -> returnBc (False, panic "ByteCodeGen.generateCCall(dyn)")
907 -> ioToBc (lookupStaticPtr target) `thenBc` \res ->
910 -> pprPanic "ByteCodeGen.generateCCall: casm" (ppr ccall_spec)
912 get_target_info `thenBc` \ (is_static, static_target_addr) ->
915 -- Get the arg reps, zapping the leading Addr# in the dynamic case
916 a_reps -- | trace (showSDoc (ppr a_reps_pushed_RAW)) False = error "???"
917 | is_static = a_reps_pushed_RAW
918 | otherwise = if null a_reps_pushed_RAW
919 then panic "ByteCodeGen.generateCCall: dyn with no args"
920 else tail a_reps_pushed_RAW
923 (push_Addr, d_after_Addr)
925 = (toOL [PUSH_UBX (Right static_target_addr) addr_sizeW],
926 d_after_args + addr_sizeW)
927 | otherwise -- is already on the stack
928 = (nilOL, d_after_args)
930 -- Push the return placeholder. For a call returning nothing,
931 -- this is a VoidRep (tag).
932 r_sizeW = getPrimRepSize r_rep
933 d_after_r = d_after_Addr + r_sizeW
934 r_lit = mkDummyLiteral r_rep
935 push_r = (if returns_void
937 else unitOL (PUSH_UBX (Left r_lit) r_sizeW))
939 -- generate the marshalling code we're going to call
942 arg1_offW = r_sizeW + addr_sizeW
943 args_offW = map (arg1_offW +)
944 (init (scanl (+) 0 (map getPrimRepSize a_reps)))
946 ioToBc (mkMarshalCode cconv
947 (r_offW, r_rep) addr_offW
948 (zip args_offW a_reps)) `thenBc` \ addr_of_marshaller ->
949 recordMallocBc addr_of_marshaller `thenBc_`
951 -- Offset of the next stack frame down the stack. The CCALL
952 -- instruction needs to describe the chunk of stack containing
953 -- the ccall args to the GC, so it needs to know how large it
954 -- is. See comment in Interpreter.c with the CCALL instruction.
955 stk_offset = d_after_r - s
958 do_call = unitOL (CCALL stk_offset (castPtr addr_of_marshaller))
960 wrapup = mkSLIDE r_sizeW (d_after_r - r_sizeW - s)
961 `snocOL` RETURN_UBX r_rep
963 --trace (show (arg1_offW, args_offW , (map getPrimRepSize a_reps) )) $
966 push_Addr `appOL` push_r `appOL` do_call `appOL` wrapup
970 -- Make a dummy literal, to be used as a placeholder for FFI return
971 -- values on the stack.
972 mkDummyLiteral :: PrimRep -> Literal
975 CharRep -> MachChar 0
977 WordRep -> MachWord 0
978 DoubleRep -> MachDouble 0
979 FloatRep -> MachFloat 0
980 AddrRep | getPrimRepSize AddrRep == getPrimRepSize WordRep -> MachWord 0
981 _ -> moan64 "mkDummyLiteral" (ppr pr)
985 -- GHC.Prim.Char# -> GHC.Prim.State# GHC.Prim.RealWorld
986 -- -> (# GHC.Prim.State# GHC.Prim.RealWorld, GHC.Prim.Int# #)
989 -- and check that an unboxed pair is returned wherein the first arg is VoidRep'd.
991 -- Alternatively, for call-targets returning nothing, convert
993 -- GHC.Prim.Char# -> GHC.Prim.State# GHC.Prim.RealWorld
994 -- -> (# GHC.Prim.State# GHC.Prim.RealWorld #)
998 maybe_getCCallReturnRep :: Type -> Maybe PrimRep
999 maybe_getCCallReturnRep fn_ty
1000 = let (a_tys, r_ty) = splitFunTys (dropForAlls fn_ty)
1002 = if isSingleton r_reps then Nothing else Just (r_reps !! 1)
1004 = case splitTyConApp_maybe (repType r_ty) of
1005 (Just (tyc, tys)) -> (tyc, map typePrimRep tys)
1007 ok = ( ( r_reps `lengthIs` 2 && VoidRep == head r_reps)
1008 || r_reps == [VoidRep] )
1009 && isUnboxedTupleTyCon r_tycon
1010 && case maybe_r_rep_to_go of
1012 Just r_rep -> r_rep /= PtrRep
1013 -- if it was, it would be impossible
1014 -- to create a valid return value
1015 -- placeholder on the stack
1016 blargh = pprPanic "maybe_getCCallReturn: can't handle:"
1019 --trace (showSDoc (ppr (a_reps, r_reps))) $
1020 if ok then maybe_r_rep_to_go else blargh
1022 -- Compile code which expects an unboxed Int on the top of stack,
1023 -- (call it i), and pushes the i'th closure in the supplied list
1024 -- as a consequence.
1025 implement_tagToId :: [Name] -> BcM BCInstrList
1026 implement_tagToId names
1027 = ASSERT( notNull names )
1028 getLabelsBc (length names) `thenBc` \ labels ->
1029 getLabelBc `thenBc` \ label_fail ->
1030 getLabelBc `thenBc` \ label_exit ->
1031 zip4 labels (tail labels ++ [label_fail])
1032 [0 ..] names `bind` \ infos ->
1033 map (mkStep label_exit) infos `bind` \ steps ->
1034 returnBc (concatOL steps
1036 toOL [LABEL label_fail, CASEFAIL, LABEL label_exit])
1038 mkStep l_exit (my_label, next_label, n, name_for_n)
1039 = toOL [LABEL my_label,
1040 TESTEQ_I n next_label,
1045 -- -----------------------------------------------------------------------------
1048 -- Push an atom onto the stack, returning suitable code & number of
1049 -- stack words used.
1051 -- The env p must map each variable to the highest- numbered stack
1052 -- slot for it. For example, if the stack has depth 4 and we
1053 -- tagged-ly push (v :: Int#) on it, the value will be in stack[4],
1054 -- the tag in stack[5], the stack will have depth 6, and p must map v
1055 -- to 5 and not to 4. Stack locations are numbered from zero, so a
1056 -- depth 6 stack has valid words 0 .. 5.
1058 pushAtom :: Int -> BCEnv -> AnnExpr' Id VarSet -> BcM (BCInstrList, Int)
1060 pushAtom d p (AnnApp f (_, AnnType _))
1061 = pushAtom d p (snd f)
1063 pushAtom d p (AnnNote note e)
1064 = pushAtom d p (snd e)
1066 pushAtom d p (AnnLam x e)
1068 = pushAtom d p (snd e)
1070 pushAtom d p (AnnVar v)
1072 | idPrimRep v == VoidRep
1073 = returnBc (nilOL, 0)
1076 = pprPanic "pushAtom: shouldn't get an FCallId here" (ppr v)
1078 | Just primop <- isPrimOpId_maybe v
1079 = returnBc (unitOL (PUSH_PRIMOP primop), 1)
1083 -- d - d_v the number of words between the TOS
1084 -- and the 1st slot of the object
1086 -- d - d_v - 1 the offset from the TOS of the 1st slot
1088 -- d - d_v - 1 + sz - 1 the offset from the TOS of the last slot
1091 -- Having found the last slot, we proceed to copy the right number of
1092 -- slots on to the top of the stack.
1095 = case lookupBCEnv_maybe p v of
1096 Just d_v -> (toOL (nOfThem sz (PUSH_L (d-d_v+sz-2))), sz)
1097 Nothing -> ASSERT(sz == 1) (unitOL (PUSH_G nm), sz)
1099 nm = case isDataConId_maybe v of
1101 Nothing -> getName v
1108 pushAtom d p (AnnLit lit)
1110 MachLabel fs -> code CodePtrRep
1111 MachWord w -> code WordRep
1112 MachInt i -> code IntRep
1113 MachFloat r -> code FloatRep
1114 MachDouble r -> code DoubleRep
1115 MachChar c -> code CharRep
1116 MachStr s -> pushStr s
1119 = let size_host_words = getPrimRepSize rep
1120 in returnBc (unitOL (PUSH_UBX (Left lit) size_host_words),
1124 = let getMallocvilleAddr
1126 FastString _ l ba ->
1127 -- sigh, a string in the heap is no good to us.
1128 -- We need a static C pointer, since the type of
1129 -- a string literal is Addr#. So, copy the string
1130 -- into C land and remember the pointer so we can
1133 -- CAREFUL! Chars are 32 bits in ghc 4.09+
1134 in ioToBc (mallocBytes (n+1)) `thenBc` \ ptr ->
1135 recordMallocBc ptr `thenBc_`
1137 do memcpy ptr ba (fromIntegral n)
1138 pokeByteOff ptr n (fromIntegral (ord '\0') :: Word8)
1141 other -> panic "ByteCodeGen.pushAtom.pushStr"
1143 getMallocvilleAddr `thenBc` \ addr ->
1144 -- Get the addr on the stack, untaggedly
1145 returnBc (unitOL (PUSH_UBX (Right addr) 1), 1)
1148 = pprPanic "ByteCodeGen.pushAtom"
1149 (pprCoreExpr (deAnnotate (undefined, other)))
1151 foreign import ccall unsafe "memcpy"
1152 memcpy :: Ptr a -> ByteArray# -> CInt -> IO ()
1155 -- -----------------------------------------------------------------------------
1156 -- Given a bunch of alts code and their discrs, do the donkey work
1157 -- of making a multiway branch using a switch tree.
1158 -- What a load of hassle!
1160 mkMultiBranch :: Maybe Int -- # datacons in tycon, if alg alt
1161 -- a hint; generates better code
1162 -- Nothing is always safe
1163 -> [(Discr, BCInstrList)]
1165 mkMultiBranch maybe_ncons raw_ways
1166 = let d_way = filter (isNoDiscr.fst) raw_ways
1167 notd_ways = naturalMergeSortLe
1168 (\w1 w2 -> leAlt (fst w1) (fst w2))
1169 (filter (not.isNoDiscr.fst) raw_ways)
1171 mkTree :: [(Discr, BCInstrList)] -> Discr -> Discr -> BcM BCInstrList
1172 mkTree [] range_lo range_hi = returnBc the_default
1174 mkTree [val] range_lo range_hi
1175 | range_lo `eqAlt` range_hi
1176 = returnBc (snd val)
1178 = getLabelBc `thenBc` \ label_neq ->
1179 returnBc (mkTestEQ (fst val) label_neq
1181 `appOL` unitOL (LABEL label_neq)
1182 `appOL` the_default))
1184 mkTree vals range_lo range_hi
1185 = let n = length vals `div` 2
1186 vals_lo = take n vals
1187 vals_hi = drop n vals
1188 v_mid = fst (head vals_hi)
1190 getLabelBc `thenBc` \ label_geq ->
1191 mkTree vals_lo range_lo (dec v_mid) `thenBc` \ code_lo ->
1192 mkTree vals_hi v_mid range_hi `thenBc` \ code_hi ->
1193 returnBc (mkTestLT v_mid label_geq
1195 `appOL` unitOL (LABEL label_geq)
1199 = case d_way of [] -> unitOL CASEFAIL
1202 -- None of these will be needed if there are no non-default alts
1203 (mkTestLT, mkTestEQ, init_lo, init_hi)
1205 = panic "mkMultiBranch: awesome foursome"
1207 = case fst (head notd_ways) of {
1208 DiscrI _ -> ( \(DiscrI i) fail_label -> TESTLT_I i fail_label,
1209 \(DiscrI i) fail_label -> TESTEQ_I i fail_label,
1212 DiscrF _ -> ( \(DiscrF f) fail_label -> TESTLT_F f fail_label,
1213 \(DiscrF f) fail_label -> TESTEQ_F f fail_label,
1216 DiscrD _ -> ( \(DiscrD d) fail_label -> TESTLT_D d fail_label,
1217 \(DiscrD d) fail_label -> TESTEQ_D d fail_label,
1220 DiscrP _ -> ( \(DiscrP i) fail_label -> TESTLT_P i fail_label,
1221 \(DiscrP i) fail_label -> TESTEQ_P i fail_label,
1223 DiscrP algMaxBound )
1226 (algMinBound, algMaxBound)
1227 = case maybe_ncons of
1228 Just n -> (0, n - 1)
1229 Nothing -> (minBound, maxBound)
1231 (DiscrI i1) `eqAlt` (DiscrI i2) = i1 == i2
1232 (DiscrF f1) `eqAlt` (DiscrF f2) = f1 == f2
1233 (DiscrD d1) `eqAlt` (DiscrD d2) = d1 == d2
1234 (DiscrP i1) `eqAlt` (DiscrP i2) = i1 == i2
1235 NoDiscr `eqAlt` NoDiscr = True
1238 (DiscrI i1) `leAlt` (DiscrI i2) = i1 <= i2
1239 (DiscrF f1) `leAlt` (DiscrF f2) = f1 <= f2
1240 (DiscrD d1) `leAlt` (DiscrD d2) = d1 <= d2
1241 (DiscrP i1) `leAlt` (DiscrP i2) = i1 <= i2
1242 NoDiscr `leAlt` NoDiscr = True
1245 isNoDiscr NoDiscr = True
1248 dec (DiscrI i) = DiscrI (i-1)
1249 dec (DiscrP i) = DiscrP (i-1)
1250 dec other = other -- not really right, but if you
1251 -- do cases on floating values, you'll get what you deserve
1253 -- same snotty comment applies to the following
1255 minD, maxD :: Double
1261 mkTree notd_ways init_lo init_hi
1264 -- -----------------------------------------------------------------------------
1265 -- Supporting junk for the compilation schemes
1267 -- Describes case alts
1275 instance Outputable Discr where
1276 ppr (DiscrI i) = int i
1277 ppr (DiscrF f) = text (show f)
1278 ppr (DiscrD d) = text (show d)
1279 ppr (DiscrP i) = int i
1280 ppr NoDiscr = text "DEF"
1283 lookupBCEnv_maybe :: BCEnv -> Id -> Maybe Int
1284 lookupBCEnv_maybe = lookupFM
1286 idSizeW :: Id -> Int
1287 idSizeW id = getPrimRepSize (typePrimRep (idType id))
1289 unboxedTupleException :: a
1290 unboxedTupleException
1293 ("Bytecode generator can't handle unboxed tuples. Possibly due\n" ++
1294 "\tto foreign import/export decls in source. Workaround:\n" ++
1295 "\tcompile this module to a .o file, then restart session."))
1298 mkSLIDE n d = if d == 0 then nilOL else unitOL (SLIDE n d)
1301 splitApp :: AnnExpr' id ann -> (AnnExpr' id ann, [AnnExpr' id ann])
1302 -- The arguments are returned in *right-to-left* order
1303 splitApp (AnnApp (_,f) (_,a))
1304 | isTypeAtom a = splitApp f
1305 | otherwise = case splitApp f of
1306 (f', as) -> (f', a:as)
1307 splitApp (AnnNote n (_,e)) = splitApp e
1308 splitApp e = (e, [])
1311 isTypeAtom :: AnnExpr' id ann -> Bool
1312 isTypeAtom (AnnType _) = True
1313 isTypeAtom _ = False
1315 isVoidRepAtom :: AnnExpr' id ann -> Bool
1316 isVoidRepAtom (AnnVar v) = typePrimRep (idType v) == VoidRep
1317 isVoidRepAtom (AnnNote n (_,e)) = isVoidRepAtom e
1318 isVoidRepAtom _ = False
1320 atomRep :: AnnExpr' Id ann -> PrimRep
1321 atomRep (AnnVar v) = typePrimRep (idType v)
1322 atomRep (AnnLit l) = literalPrimRep l
1323 atomRep (AnnNote n b) = atomRep (snd b)
1324 atomRep (AnnApp f (_, AnnType _)) = atomRep (snd f)
1325 atomRep (AnnLam x e) | isTyVar x = atomRep (snd e)
1326 atomRep other = pprPanic "atomRep" (ppr (deAnnotate (undefined,other)))
1328 isPtrAtom :: AnnExpr' Id ann -> Bool
1329 isPtrAtom e = isFollowableRep (atomRep e)
1331 -- Let szsw be the sizes in words of some items pushed onto the stack,
1332 -- which has initial depth d'. Return the values which the stack environment
1333 -- should map these items to.
1334 mkStackOffsets :: Int -> [Int] -> [Int]
1335 mkStackOffsets original_depth szsw
1336 = map (subtract 1) (tail (scanl (+) original_depth szsw))
1338 -- -----------------------------------------------------------------------------
1339 -- The bytecode generator's monad
1343 nextlabel :: Int, -- for generating local labels
1344 malloced :: [Ptr ()] } -- ptrs malloced for current BCO
1345 -- Should be free()d when it is GCd
1347 newtype BcM r = BcM (BcM_State -> IO (BcM_State, r))
1349 ioToBc :: IO a -> BcM a
1350 ioToBc io = BcM $ \st -> do
1354 runBc :: BcM r -> IO (BcM_State, r)
1355 runBc (BcM m) = m (BcM_State 0 [])
1357 thenBc :: BcM a -> (a -> BcM b) -> BcM b
1358 thenBc (BcM expr) cont = BcM $ \st0 -> do
1359 (st1, q) <- expr st0
1364 thenBc_ :: BcM a -> BcM b -> BcM b
1365 thenBc_ (BcM expr) (BcM cont) = BcM $ \st0 -> do
1366 (st1, q) <- expr st0
1367 (st2, r) <- cont st1
1370 returnBc :: a -> BcM a
1371 returnBc result = BcM $ \st -> (return (st, result))
1373 instance Monad BcM where
1378 emitBc :: ([Ptr ()] -> ProtoBCO Name) -> BcM (ProtoBCO Name)
1380 = BcM $ \st -> return (st{malloced=[]}, bco (malloced st))
1382 recordMallocBc :: Ptr a -> BcM ()
1384 = BcM $ \st -> return (st{malloced = castPtr a : malloced st}, ())
1386 getLabelBc :: BcM Int
1388 = BcM $ \st -> return (st{nextlabel = 1 + nextlabel st}, nextlabel st)
1390 getLabelsBc :: Int -> BcM [Int]
1392 = BcM $ \st -> let ctr = nextlabel st
1393 in return (st{nextlabel = ctr+n}, [ctr .. ctr+n-1])