1 -----------------------------------------------------------------------------
3 -- Pretty-printing of Cmm as C, suitable for feeding gcc
5 -- (c) The University of Glasgow 2004-2006
7 -----------------------------------------------------------------------------
10 -- Print Cmm as real C, for -fvia-C
12 -- This is simpler than the old PprAbsC, because Cmm is "macro-expanded"
13 -- relative to the old AbstractC, and many oddities/decorations have
14 -- disappeared from the data type.
17 -- ToDo: save/restore volatile registers around calls.
24 #include "HsVersions.h"
51 import PprCmm () -- instances only
56 import Control.Monad.ST
58 #if x86_64_TARGET_ARCH
59 import StaticFlags ( opt_Unregisterised )
62 #if defined(alpha_TARGET_ARCH) || defined(mips_TARGET_ARCH) || defined(mipsel_TARGET_ARCH) || defined(arm_TARGET_ARCH)
63 #define BEWARE_LOAD_STORE_ALIGNMENT
66 -- --------------------------------------------------------------------------
69 pprCs :: DynFlags -> [RawCmm] -> SDoc
71 = pprCode CStyle (vcat $ map (\c -> split_marker $$ pprC c) cmms)
74 | dopt Opt_SplitObjs dflags = ptext SLIT("__STG_SPLIT_MARKER")
77 writeCs :: DynFlags -> Handle -> [RawCmm] -> IO ()
78 writeCs dflags handle cmms
79 = printForC handle (pprCs dflags cmms)
81 -- --------------------------------------------------------------------------
82 -- Now do some real work
84 -- for fun, we could call cmmToCmm over the tops...
87 pprC :: RawCmm -> SDoc
88 pprC (Cmm tops) = vcat $ intersperse (text "") $ map pprTop tops
93 pprTop :: RawCmmTop -> SDoc
94 pprTop (CmmProc info clbl _params blocks) =
96 then pprDataExterns info $$
97 pprWordArray (entryLblToInfoLbl clbl) info
101 -- the first block doesn't get a label:
102 (BasicBlock _ stmts : rest) -> vcat [
105 (if (externallyVisibleCLabel clbl)
106 then mkFN_ else mkIF_) (pprCLabel clbl) <+> lbrace,
109 nest 8 (vcat (map pprStmt stmts)) $$
110 vcat (map pprBBlock rest),
115 (temp_decls, extern_decls) = pprTempAndExternDecls blocks
118 -- Chunks of static data.
120 -- We only handle (a) arrays of word-sized things and (b) strings.
122 pprTop (CmmData _section _ds@[CmmDataLabel lbl, CmmString str]) =
124 pprLocalness lbl, ptext SLIT("char "), pprCLabel lbl,
125 ptext SLIT("[] = "), pprStringInCStyle str, semi
128 pprTop (CmmData _section _ds@[CmmDataLabel lbl, CmmUninitialised size]) =
130 pprLocalness lbl, ptext SLIT("char "), pprCLabel lbl,
131 brackets (int size), semi
134 pprTop top@(CmmData _section (CmmDataLabel lbl : lits)) =
135 pprDataExterns lits $$
136 pprWordArray lbl lits
138 -- these shouldn't appear?
139 pprTop (CmmData _ _) = panic "PprC.pprTop: can't handle this data"
142 -- --------------------------------------------------------------------------
143 -- BasicBlocks are self-contained entities: they always end in a jump.
145 -- Like nativeGen/AsmCodeGen, we could probably reorder blocks to turn
146 -- as many jumps as possible into fall throughs.
149 pprBBlock :: CmmBasicBlock -> SDoc
150 pprBBlock (BasicBlock lbl stmts) =
152 pprTrace "pprC.pprBBlock: curious empty code block for"
153 (pprBlockId lbl) empty
155 nest 4 (pprBlockId lbl <> colon) $$
156 nest 8 (vcat (map pprStmt stmts))
158 -- --------------------------------------------------------------------------
159 -- Info tables. Just arrays of words.
160 -- See codeGen/ClosureInfo, and nativeGen/PprMach
162 pprWordArray :: CLabel -> [CmmStatic] -> SDoc
164 = hcat [ pprLocalness lbl, ptext SLIT("StgWord")
165 , space, pprCLabel lbl, ptext SLIT("[] = {") ]
166 $$ nest 8 (commafy (pprStatics ds))
170 -- has to be static, if it isn't globally visible
172 pprLocalness :: CLabel -> SDoc
173 pprLocalness lbl | not $ externallyVisibleCLabel lbl = ptext SLIT("static ")
176 -- --------------------------------------------------------------------------
180 pprStmt :: CmmStmt -> SDoc
182 pprStmt stmt = case stmt of
184 CmmComment s -> (hang (ptext SLIT("/*")) 3 (ftext s)) $$ ptext SLIT("*/")
186 CmmAssign dest src -> pprAssign dest src
189 | rep == I64 && wordRep /= I64
190 -> ptext SLIT("ASSIGN_Word64") <>
191 parens (mkP_ <> pprExpr1 dest <> comma <> pprExpr src) <> semi
193 | rep == F64 && wordRep /= I64
194 -> ptext SLIT("ASSIGN_DBL") <>
195 parens (mkP_ <> pprExpr1 dest <> comma <> pprExpr src) <> semi
198 -> hsep [ pprExpr (CmmLoad dest rep), equals, pprExpr src <> semi ]
202 CmmCall (CmmForeignCall fn cconv) results args safety ->
203 -- Controversial: leave this out for now.
206 pprCall ppr_fn cconv results args safety
209 CmmLit (CmmLabel lbl) -> pprCLabel lbl
210 _ -> parens (cCast (pprCFunType cconv results args) fn)
211 -- for a dynamic call, cast the expression to
212 -- a function of the right type (we hope).
214 -- we #undef a function before calling it: the FFI is supposed to be
215 -- an interface specifically to C, not to C+CPP. For one thing, this
216 -- makes the via-C route more compatible with the NCG. If macros
217 -- are being used for optimisation, then inline functions are probably
219 pprUndef (CmmLit (CmmLabel lbl)) =
220 ptext SLIT("#undef") <+> pprCLabel lbl
223 CmmCall (CmmPrim op) results args safety ->
224 pprCall ppr_fn CCallConv results args safety
226 ppr_fn = pprCallishMachOp_for_C op
228 CmmBranch ident -> pprBranch ident
229 CmmCondBranch expr ident -> pprCondBranch expr ident
230 CmmJump lbl _params -> mkJMP_(pprExpr lbl) <> semi
231 CmmSwitch arg ids -> pprSwitch arg ids
233 pprCFunType :: CCallConv -> CmmHintFormals -> CmmActuals -> SDoc
234 pprCFunType cconv ress args
237 parens (text (ccallConvAttribute cconv) <> char '*'),
238 parens (commafy (map arg_type args))
241 res_type [] = ptext SLIT("void")
242 res_type [(one,hint)] = machRepHintCType (localRegRep one) hint
244 arg_type (expr,hint) = machRepHintCType (cmmExprRep expr) hint
246 -- ---------------------------------------------------------------------
247 -- unconditional branches
248 pprBranch :: BlockId -> SDoc
249 pprBranch ident = ptext SLIT("goto") <+> pprBlockId ident <> semi
252 -- ---------------------------------------------------------------------
253 -- conditional branches to local labels
254 pprCondBranch :: CmmExpr -> BlockId -> SDoc
255 pprCondBranch expr ident
256 = hsep [ ptext SLIT("if") , parens(pprExpr expr) ,
257 ptext SLIT("goto") , (pprBlockId ident) <> semi ]
260 -- ---------------------------------------------------------------------
261 -- a local table branch
263 -- we find the fall-through cases
265 -- N.B. we remove Nothing's from the list of branches, as they are
266 -- 'undefined'. However, they may be defined one day, so we better
267 -- document this behaviour.
269 pprSwitch :: CmmExpr -> [ Maybe BlockId ] -> SDoc
270 pprSwitch e maybe_ids
271 = let pairs = [ (ix, ident) | (ix,Just ident) <- zip [0..] maybe_ids ]
272 pairs2 = [ (map fst as, snd (head as)) | as <- groupBy sndEq pairs ]
274 (hang (ptext SLIT("switch") <+> parens ( pprExpr e ) <+> lbrace)
275 4 (vcat ( map caseify pairs2 )))
279 sndEq (_,x) (_,y) = x == y
282 caseify (ix:ixs, ident) = vcat (map do_fallthrough ixs) $$ final_branch ix
285 hsep [ ptext SLIT("case") , pprHexVal ix wordRep <> colon ,
286 ptext SLIT("/* fall through */") ]
289 hsep [ ptext SLIT("case") , pprHexVal ix wordRep <> colon ,
290 ptext SLIT("goto") , (pprBlockId ident) <> semi ]
292 -- ---------------------------------------------------------------------
296 -- C Types: the invariant is that the C expression generated by
300 -- has a type in C which is also given by
302 -- machRepCType (cmmExprRep e)
304 -- (similar invariants apply to the rest of the pretty printer).
306 pprExpr :: CmmExpr -> SDoc
307 pprExpr e = case e of
308 CmmLit lit -> pprLit lit
310 CmmLoad e I64 | wordRep /= I64
311 -> ptext SLIT("PK_Word64") <> parens (mkP_ <> pprExpr1 e)
313 CmmLoad e F64 | wordRep /= I64
314 -> ptext SLIT("PK_DBL") <> parens (mkP_ <> pprExpr1 e)
316 CmmLoad (CmmReg r) rep
317 | isPtrReg r && rep == wordRep
318 -> char '*' <> pprAsPtrReg r
320 CmmLoad (CmmRegOff r 0) rep
321 | isPtrReg r && rep == wordRep
322 -> char '*' <> pprAsPtrReg r
324 CmmLoad (CmmRegOff r off) rep
325 | isPtrReg r && rep == wordRep
326 -- ToDo: check that the offset is a word multiple?
327 -> pprAsPtrReg r <> brackets (ppr (off `shiftR` wordShift))
333 CmmReg reg -> pprCastReg reg
334 CmmRegOff reg 0 -> pprCastReg reg
337 | i > 0 -> pprRegOff (char '+') i
338 | otherwise -> pprRegOff (char '-') (-i)
340 pprRegOff op i' = pprCastReg reg <> op <> int i'
342 CmmMachOp mop args -> pprMachOpApp mop args
344 pprExpr1 :: CmmExpr -> SDoc
345 pprExpr1 (CmmLit lit) = pprLit1 lit
346 pprExpr1 e@(CmmReg _reg) = pprExpr e
347 pprExpr1 other = parens (pprExpr other)
349 -- --------------------------------------------------------------------------
350 -- MachOp applications
352 pprMachOpApp :: MachOp -> [CmmExpr] -> SDoc
356 = ptext SLIT("mulIntMayOflo") <> parens (commafy (map pprExpr args))
357 where isMulMayOfloOp (MO_U_MulMayOflo _) = True
358 isMulMayOfloOp (MO_S_MulMayOflo _) = True
359 isMulMayOfloOp _ = False
361 pprMachOpApp mop args
362 | Just ty <- machOpNeedsCast mop
363 = ty <> parens (pprMachOpApp' mop args)
365 = pprMachOpApp' mop args
367 -- Comparisons in C have type 'int', but we want type W_ (this is what
368 -- resultRepOfMachOp says). The other C operations inherit their type
369 -- from their operands, so no casting is required.
370 machOpNeedsCast :: MachOp -> Maybe SDoc
372 | isComparisonMachOp mop = Just mkW_
373 | otherwise = Nothing
375 pprMachOpApp' mop args
378 [x,y] -> pprArg x <+> pprMachOp_for_C mop <+> pprArg y
381 [x] -> pprMachOp_for_C mop <> parens (pprArg x)
383 _ -> panic "PprC.pprMachOp : machop with wrong number of args"
386 pprArg e | signedOp mop = cCast (machRepSignedCType (cmmExprRep e)) e
387 | otherwise = pprExpr1 e
389 -- --------------------------------------------------------------------------
392 pprLit :: CmmLit -> SDoc
393 pprLit lit = case lit of
394 CmmInt i rep -> pprHexVal i rep
395 CmmFloat f rep -> parens (machRepCType rep) <> (rational f)
396 CmmLabel clbl -> mkW_ <> pprCLabelAddr clbl
397 CmmLabelOff clbl i -> mkW_ <> pprCLabelAddr clbl <> char '+' <> int i
398 CmmLabelDiffOff clbl1 clbl2 i
400 -- * the lit must occur in the info table clbl2
401 -- * clbl1 must be an SRT, a slow entry point or a large bitmap
402 -- The Mangler is expected to convert any reference to an SRT,
403 -- a slow entry point or a large bitmap
404 -- from an info table to an offset.
405 -> mkW_ <> pprCLabelAddr clbl1 <> char '+' <> int i
407 pprCLabelAddr lbl = char '&' <> pprCLabel lbl
409 pprLit1 :: CmmLit -> SDoc
410 pprLit1 lit@(CmmLabelOff _ _) = parens (pprLit lit)
411 pprLit1 lit@(CmmLabelDiffOff _ _ _) = parens (pprLit lit)
412 pprLit1 lit@(CmmFloat _ _) = parens (pprLit lit)
413 pprLit1 other = pprLit other
415 -- ---------------------------------------------------------------------------
418 pprStatics :: [CmmStatic] -> [SDoc]
420 pprStatics (CmmStaticLit (CmmFloat f F32) : rest)
421 = pprLit1 (floatToWord f) : pprStatics rest
422 pprStatics (CmmStaticLit (CmmFloat f F64) : rest)
423 = map pprLit1 (doubleToWords f) ++ pprStatics rest
424 pprStatics (CmmStaticLit (CmmInt i I64) : rest)
425 | machRepByteWidth I32 == wORD_SIZE
426 #ifdef WORDS_BIGENDIAN
427 = pprStatics (CmmStaticLit (CmmInt q I32) :
428 CmmStaticLit (CmmInt r I32) : rest)
430 = pprStatics (CmmStaticLit (CmmInt r I32) :
431 CmmStaticLit (CmmInt q I32) : rest)
433 where r = i .&. 0xffffffff
435 pprStatics (CmmStaticLit (CmmInt i rep) : rest)
436 | machRepByteWidth rep /= wORD_SIZE
437 = panic "pprStatics: cannot emit a non-word-sized static literal"
438 pprStatics (CmmStaticLit lit : rest)
439 = pprLit1 lit : pprStatics rest
440 pprStatics (other : rest)
441 = pprPanic "pprWord" (pprStatic other)
443 pprStatic :: CmmStatic -> SDoc
444 pprStatic s = case s of
446 CmmStaticLit lit -> nest 4 (pprLit lit)
447 CmmAlign i -> nest 4 (ptext SLIT("/* align */") <+> int i)
448 CmmDataLabel clbl -> pprCLabel clbl <> colon
449 CmmUninitialised i -> nest 4 (mkC_ <> brackets (int i))
451 -- these should be inlined, like the old .hc
452 CmmString s' -> nest 4 (mkW_ <> parens(pprStringInCStyle s'))
455 -- ---------------------------------------------------------------------------
458 pprBlockId :: BlockId -> SDoc
459 pprBlockId b = char '_' <> ppr (getUnique b)
461 -- --------------------------------------------------------------------------
462 -- Print a MachOp in a way suitable for emitting via C.
465 pprMachOp_for_C :: MachOp -> SDoc
467 pprMachOp_for_C mop = case mop of
469 -- Integer operations
472 MO_Eq _ -> ptext SLIT("==")
473 MO_Ne _ -> ptext SLIT("!=")
476 MO_S_Quot _ -> char '/'
477 MO_S_Rem _ -> char '%'
478 MO_S_Neg _ -> char '-'
480 MO_U_Quot _ -> char '/'
481 MO_U_Rem _ -> char '%'
483 -- Signed comparisons (floating-point comparisons also use these)
484 -- & Unsigned comparisons
485 MO_S_Ge _ -> ptext SLIT(">=")
486 MO_S_Le _ -> ptext SLIT("<=")
487 MO_S_Gt _ -> char '>'
488 MO_S_Lt _ -> char '<'
490 MO_U_Ge _ -> ptext SLIT(">=")
491 MO_U_Le _ -> ptext SLIT("<=")
492 MO_U_Gt _ -> char '>'
493 MO_U_Lt _ -> char '<'
495 -- Bitwise operations. Not all of these may be supported at all
496 -- sizes, and only integral MachReps are valid.
501 MO_Shl _ -> ptext SLIT("<<")
502 MO_U_Shr _ -> ptext SLIT(">>") -- unsigned shift right
503 MO_S_Shr _ -> ptext SLIT(">>") -- signed shift right
505 -- Conversions. Some of these will be NOPs.
506 -- Floating-point conversions use the signed variant.
507 -- We won't know to generate (void*) casts here, but maybe from
511 MO_U_Conv I8 I8 -> empty
512 MO_U_Conv I16 I16 -> empty
513 MO_U_Conv I32 I32 -> empty
514 MO_U_Conv I64 I64 -> empty
515 MO_U_Conv I128 I128 -> empty
516 MO_S_Conv I8 I8 -> empty
517 MO_S_Conv I16 I16 -> empty
518 MO_S_Conv I32 I32 -> empty
519 MO_S_Conv I64 I64 -> empty
520 MO_S_Conv I128 I128 -> empty
522 MO_U_Conv _from to -> parens (machRepCType to)
523 MO_S_Conv _from to -> parens (machRepSignedCType to)
525 _ -> panic "PprC.pprMachOp_for_C: unknown machop"
527 signedOp :: MachOp -> Bool
528 signedOp (MO_S_Quot _) = True
529 signedOp (MO_S_Rem _) = True
530 signedOp (MO_S_Neg _) = True
531 signedOp (MO_S_Ge _) = True
532 signedOp (MO_S_Le _) = True
533 signedOp (MO_S_Gt _) = True
534 signedOp (MO_S_Lt _) = True
535 signedOp (MO_S_Shr _) = True
536 signedOp (MO_S_Conv _ _) = True
539 -- ---------------------------------------------------------------------
540 -- tend to be implemented by foreign calls
542 pprCallishMachOp_for_C :: CallishMachOp -> SDoc
544 pprCallishMachOp_for_C mop
546 MO_F64_Pwr -> ptext SLIT("pow")
547 MO_F64_Sin -> ptext SLIT("sin")
548 MO_F64_Cos -> ptext SLIT("cos")
549 MO_F64_Tan -> ptext SLIT("tan")
550 MO_F64_Sinh -> ptext SLIT("sinh")
551 MO_F64_Cosh -> ptext SLIT("cosh")
552 MO_F64_Tanh -> ptext SLIT("tanh")
553 MO_F64_Asin -> ptext SLIT("asin")
554 MO_F64_Acos -> ptext SLIT("acos")
555 MO_F64_Atan -> ptext SLIT("atan")
556 MO_F64_Log -> ptext SLIT("log")
557 MO_F64_Exp -> ptext SLIT("exp")
558 MO_F64_Sqrt -> ptext SLIT("sqrt")
559 MO_F32_Pwr -> ptext SLIT("powf")
560 MO_F32_Sin -> ptext SLIT("sinf")
561 MO_F32_Cos -> ptext SLIT("cosf")
562 MO_F32_Tan -> ptext SLIT("tanf")
563 MO_F32_Sinh -> ptext SLIT("sinhf")
564 MO_F32_Cosh -> ptext SLIT("coshf")
565 MO_F32_Tanh -> ptext SLIT("tanhf")
566 MO_F32_Asin -> ptext SLIT("asinf")
567 MO_F32_Acos -> ptext SLIT("acosf")
568 MO_F32_Atan -> ptext SLIT("atanf")
569 MO_F32_Log -> ptext SLIT("logf")
570 MO_F32_Exp -> ptext SLIT("expf")
571 MO_F32_Sqrt -> ptext SLIT("sqrtf")
572 MO_WriteBarrier -> ptext SLIT("write_barrier")
574 -- ---------------------------------------------------------------------
578 mkJMP_, mkFN_, mkIF_ :: SDoc -> SDoc
580 mkJMP_ i = ptext SLIT("JMP_") <> parens i
581 mkFN_ i = ptext SLIT("FN_") <> parens i -- externally visible function
582 mkIF_ i = ptext SLIT("IF_") <> parens i -- locally visible
586 mkFB_ = ptext SLIT("FB_") -- function code begin
587 mkFE_ = ptext SLIT("FE_") -- function code end
589 -- from includes/Stg.h
591 mkC_,mkW_,mkP_,mkPP_,mkI_,mkA_,mkD_,mkF_,mkB_,mkL_,mkLI_,mkLW_ :: SDoc
593 mkC_ = ptext SLIT("(C_)") -- StgChar
594 mkW_ = ptext SLIT("(W_)") -- StgWord
595 mkP_ = ptext SLIT("(P_)") -- StgWord*
596 mkPP_ = ptext SLIT("(PP_)") -- P_*
597 mkI_ = ptext SLIT("(I_)") -- StgInt
598 mkA_ = ptext SLIT("(A_)") -- StgAddr
599 mkD_ = ptext SLIT("(D_)") -- const StgWord*
600 mkF_ = ptext SLIT("(F_)") -- StgFunPtr
601 mkB_ = ptext SLIT("(B_)") -- StgByteArray
602 mkL_ = ptext SLIT("(L_)") -- StgClosurePtr
604 mkLI_ = ptext SLIT("(LI_)") -- StgInt64
605 mkLW_ = ptext SLIT("(LW_)") -- StgWord64
608 -- ---------------------------------------------------------------------
612 -- Generating assignments is what we're all about, here
614 pprAssign :: CmmReg -> CmmExpr -> SDoc
616 -- dest is a reg, rhs is a reg
617 pprAssign r1 (CmmReg r2)
618 | isPtrReg r1 && isPtrReg r2
619 = hcat [ pprAsPtrReg r1, equals, pprAsPtrReg r2, semi ]
621 -- dest is a reg, rhs is a CmmRegOff
622 pprAssign r1 (CmmRegOff r2 off)
623 | isPtrReg r1 && isPtrReg r2 && (off `rem` wORD_SIZE == 0)
624 = hcat [ pprAsPtrReg r1, equals, pprAsPtrReg r2, op, int off', semi ]
626 off1 = off `shiftR` wordShift
628 (op,off') | off >= 0 = (char '+', off1)
629 | otherwise = (char '-', -off1)
631 -- dest is a reg, rhs is anything.
632 -- We can't cast the lvalue, so we have to cast the rhs if necessary. Casting
633 -- the lvalue elicits a warning from new GCC versions (3.4+).
636 = pprReg r1 <> ptext SLIT(" = ") <> mkP_ <> pprExpr1 r2 <> semi
637 | Just ty <- strangeRegType r1
638 = pprReg r1 <> ptext SLIT(" = ") <> parens ty <> pprExpr1 r2 <> semi
640 = pprReg r1 <> ptext SLIT(" = ") <> pprExpr r2 <> semi
642 -- ---------------------------------------------------------------------
646 | isStrangeTypeReg reg = mkW_ <> pprReg reg
647 | otherwise = pprReg reg
649 -- True if (pprReg reg) will give an expression with type StgPtr. We
650 -- need to take care with pointer arithmetic on registers with type
652 isFixedPtrReg :: CmmReg -> Bool
653 isFixedPtrReg (CmmLocal _) = False
654 isFixedPtrReg (CmmGlobal r) = isFixedPtrGlobalReg r
656 -- True if (pprAsPtrReg reg) will give an expression with type StgPtr
657 isPtrReg :: CmmReg -> Bool
658 isPtrReg (CmmLocal _) = False
659 isPtrReg (CmmGlobal (VanillaReg n)) = True -- if we print via pprAsPtrReg
660 isPtrReg (CmmGlobal reg) = isFixedPtrGlobalReg reg
662 -- True if this global reg has type StgPtr
663 isFixedPtrGlobalReg :: GlobalReg -> Bool
664 isFixedPtrGlobalReg Sp = True
665 isFixedPtrGlobalReg Hp = True
666 isFixedPtrGlobalReg HpLim = True
667 isFixedPtrGlobalReg SpLim = True
668 isFixedPtrGlobalReg _ = False
670 -- True if in C this register doesn't have the type given by
671 -- (machRepCType (cmmRegRep reg)), so it has to be cast.
672 isStrangeTypeReg :: CmmReg -> Bool
673 isStrangeTypeReg (CmmLocal _) = False
674 isStrangeTypeReg (CmmGlobal g) = isStrangeTypeGlobal g
676 isStrangeTypeGlobal :: GlobalReg -> Bool
677 isStrangeTypeGlobal CurrentTSO = True
678 isStrangeTypeGlobal CurrentNursery = True
679 isStrangeTypeGlobal BaseReg = True
680 isStrangeTypeGlobal r = isFixedPtrGlobalReg r
682 strangeRegType :: CmmReg -> Maybe SDoc
683 strangeRegType (CmmGlobal CurrentTSO) = Just (ptext SLIT("struct StgTSO_ *"))
684 strangeRegType (CmmGlobal CurrentNursery) = Just (ptext SLIT("struct bdescr_ *"))
685 strangeRegType (CmmGlobal BaseReg) = Just (ptext SLIT("struct StgRegTable_ *"))
686 strangeRegType _ = Nothing
688 -- pprReg just prints the register name.
690 pprReg :: CmmReg -> SDoc
692 CmmLocal local -> pprLocalReg local
693 CmmGlobal global -> pprGlobalReg global
695 pprAsPtrReg :: CmmReg -> SDoc
696 pprAsPtrReg (CmmGlobal (VanillaReg n)) = char 'R' <> int n <> ptext SLIT(".p")
697 pprAsPtrReg other_reg = pprReg other_reg
699 pprGlobalReg :: GlobalReg -> SDoc
700 pprGlobalReg gr = case gr of
701 VanillaReg n -> char 'R' <> int n <> ptext SLIT(".w")
702 FloatReg n -> char 'F' <> int n
703 DoubleReg n -> char 'D' <> int n
704 LongReg n -> char 'L' <> int n
705 Sp -> ptext SLIT("Sp")
706 SpLim -> ptext SLIT("SpLim")
707 Hp -> ptext SLIT("Hp")
708 HpLim -> ptext SLIT("HpLim")
709 CurrentTSO -> ptext SLIT("CurrentTSO")
710 CurrentNursery -> ptext SLIT("CurrentNursery")
711 HpAlloc -> ptext SLIT("HpAlloc")
712 BaseReg -> ptext SLIT("BaseReg")
713 GCEnter1 -> ptext SLIT("stg_gc_enter_1")
714 GCFun -> ptext SLIT("stg_gc_fun")
716 pprLocalReg :: LocalReg -> SDoc
717 pprLocalReg (LocalReg uniq _ _) = char '_' <> ppr uniq
719 -- -----------------------------------------------------------------------------
722 pprCall :: SDoc -> CCallConv -> CmmHintFormals -> CmmActuals -> CmmSafety
725 pprCall ppr_fn cconv results args _
726 | not (is_cish cconv)
727 = panic "pprCall: unknown calling convention"
731 #if x86_64_TARGET_ARCH
732 -- HACK around gcc optimisations.
733 -- x86_64 needs a __DISCARD__() here, to create a barrier between
734 -- putting the arguments into temporaries and passing the arguments
735 -- to the callee, because the argument expressions may refer to
736 -- machine registers that are also used for passing arguments in the
737 -- C calling convention.
738 (if (not opt_Unregisterised)
739 then ptext SLIT("__DISCARD__();")
742 ppr_assign results (ppr_fn <> parens (commafy (map pprArg args))) <> semi
744 ppr_assign [] rhs = rhs
745 ppr_assign [(one,hint)] rhs
746 = pprLocalReg one <> ptext SLIT(" = ")
747 <> pprUnHint hint (localRegRep one) <> rhs
748 ppr_assign _other _rhs = panic "pprCall: multiple results"
750 pprArg (expr, PtrHint)
751 = cCast (ptext SLIT("void *")) expr
752 -- see comment by machRepHintCType below
753 pprArg (expr, SignedHint)
754 = cCast (machRepSignedCType (cmmExprRep expr)) expr
755 pprArg (expr, _other)
758 pprUnHint PtrHint rep = parens (machRepCType rep)
759 pprUnHint SignedHint rep = parens (machRepCType rep)
760 pprUnHint _ _ = empty
762 pprGlobalRegName :: GlobalReg -> SDoc
763 pprGlobalRegName gr = case gr of
764 VanillaReg n -> char 'R' <> int n -- without the .w suffix
767 -- Currently we only have these two calling conventions, but this might
768 -- change in the future...
769 is_cish CCallConv = True
770 is_cish StdCallConv = True
772 -- ---------------------------------------------------------------------
773 -- Find and print local and external declarations for a list of
776 pprTempAndExternDecls :: [CmmBasicBlock] -> (SDoc{-temps-}, SDoc{-externs-})
777 pprTempAndExternDecls stmts
778 = (vcat (map pprTempDecl (eltsUFM temps)),
779 vcat (map (pprExternDecl False{-ToDo-}) (keysFM lbls)))
780 where (temps, lbls) = runTE (mapM_ te_BB stmts)
782 pprDataExterns :: [CmmStatic] -> SDoc
783 pprDataExterns statics
784 = vcat (map (pprExternDecl False{-ToDo-}) (keysFM lbls))
785 where (_, lbls) = runTE (mapM_ te_Static statics)
787 pprTempDecl :: LocalReg -> SDoc
788 pprTempDecl l@(LocalReg _ rep _)
789 = hcat [ machRepCType rep, space, pprLocalReg l, semi ]
791 pprExternDecl :: Bool -> CLabel -> SDoc
792 pprExternDecl in_srt lbl
793 -- do not print anything for "known external" things
794 | not (needsCDecl lbl) = empty
796 hcat [ visibility, label_type (labelType lbl),
797 lparen, dyn_wrapper (pprCLabel lbl), text ");" ]
800 | in_srt && labelDynamic lbl = text "DLL_IMPORT_DATA_VAR" <> parens d
803 label_type CodeLabel = ptext SLIT("F_")
804 label_type DataLabel = ptext SLIT("I_")
807 | externallyVisibleCLabel lbl = char 'E'
808 | otherwise = char 'I'
811 type TEState = (UniqSet LocalReg, FiniteMap CLabel ())
812 newtype TE a = TE { unTE :: TEState -> (a, TEState) }
814 instance Monad TE where
815 TE m >>= k = TE $ \s -> case m s of (a, s') -> unTE (k a) s'
816 return a = TE $ \s -> (a, s)
818 te_lbl :: CLabel -> TE ()
819 te_lbl lbl = TE $ \(temps,lbls) -> ((), (temps, addToFM lbls lbl ()))
821 te_temp :: LocalReg -> TE ()
822 te_temp r = TE $ \(temps,lbls) -> ((), (addOneToUniqSet temps r, lbls))
824 runTE :: TE () -> TEState
825 runTE (TE m) = snd (m (emptyUniqSet, emptyFM))
827 te_Static :: CmmStatic -> TE ()
828 te_Static (CmmStaticLit lit) = te_Lit lit
829 te_Static _ = return ()
831 te_BB :: CmmBasicBlock -> TE ()
832 te_BB (BasicBlock _ ss) = mapM_ te_Stmt ss
834 te_Lit :: CmmLit -> TE ()
835 te_Lit (CmmLabel l) = te_lbl l
836 te_Lit (CmmLabelOff l _) = te_lbl l
837 te_Lit (CmmLabelDiffOff l1 l2 _) = te_lbl l1
840 te_Stmt :: CmmStmt -> TE ()
841 te_Stmt (CmmAssign r e) = te_Reg r >> te_Expr e
842 te_Stmt (CmmStore l r) = te_Expr l >> te_Expr r
843 te_Stmt (CmmCall _ rs es _) = mapM_ (te_temp.fst) rs >>
844 mapM_ (te_Expr.fst) es
845 te_Stmt (CmmCondBranch e _) = te_Expr e
846 te_Stmt (CmmSwitch e _) = te_Expr e
847 te_Stmt (CmmJump e _) = te_Expr e
848 te_Stmt _ = return ()
850 te_Expr :: CmmExpr -> TE ()
851 te_Expr (CmmLit lit) = te_Lit lit
852 te_Expr (CmmLoad e _) = te_Expr e
853 te_Expr (CmmReg r) = te_Reg r
854 te_Expr (CmmMachOp _ es) = mapM_ te_Expr es
855 te_Expr (CmmRegOff r _) = te_Reg r
857 te_Reg :: CmmReg -> TE ()
858 te_Reg (CmmLocal l) = te_temp l
862 -- ---------------------------------------------------------------------
863 -- C types for MachReps
865 cCast :: SDoc -> CmmExpr -> SDoc
866 cCast ty expr = parens ty <> pprExpr1 expr
868 cLoad :: CmmExpr -> MachRep -> SDoc
869 #ifdef BEWARE_LOAD_STORE_ALIGNMENT
871 let decl = machRepCType rep <+> ptext SLIT("x") <> semi
872 struct = ptext SLIT("struct") <+> braces (decl)
873 packed_attr = ptext SLIT("__attribute__((packed))")
874 cast = parens (struct <+> packed_attr <> char '*')
875 in parens (cast <+> pprExpr1 expr) <> ptext SLIT("->x")
877 cLoad expr rep = char '*' <> parens (cCast (machRepPtrCType rep) expr)
880 -- This is for finding the types of foreign call arguments. For a pointer
881 -- argument, we always cast the argument to (void *), to avoid warnings from
883 machRepHintCType :: MachRep -> MachHint -> SDoc
884 machRepHintCType rep PtrHint = ptext SLIT("void *")
885 machRepHintCType rep SignedHint = machRepSignedCType rep
886 machRepHintCType rep _other = machRepCType rep
888 machRepPtrCType :: MachRep -> SDoc
889 machRepPtrCType r | r == wordRep = ptext SLIT("P_")
890 | otherwise = machRepCType r <> char '*'
892 machRepCType :: MachRep -> SDoc
893 machRepCType r | r == wordRep = ptext SLIT("W_")
894 | otherwise = sized_type
895 where sized_type = case r of
896 I8 -> ptext SLIT("StgWord8")
897 I16 -> ptext SLIT("StgWord16")
898 I32 -> ptext SLIT("StgWord32")
899 I64 -> ptext SLIT("StgWord64")
900 F32 -> ptext SLIT("StgFloat") -- ToDo: correct?
901 F64 -> ptext SLIT("StgDouble")
902 _ -> panic "machRepCType"
904 machRepSignedCType :: MachRep -> SDoc
905 machRepSignedCType r | r == wordRep = ptext SLIT("I_")
906 | otherwise = sized_type
907 where sized_type = case r of
908 I8 -> ptext SLIT("StgInt8")
909 I16 -> ptext SLIT("StgInt16")
910 I32 -> ptext SLIT("StgInt32")
911 I64 -> ptext SLIT("StgInt64")
912 F32 -> ptext SLIT("StgFloat") -- ToDo: correct?
913 F64 -> ptext SLIT("StgDouble")
914 _ -> panic "machRepCType"
916 -- ---------------------------------------------------------------------
917 -- print strings as valid C strings
919 pprStringInCStyle :: [Word8] -> SDoc
920 pprStringInCStyle s = doubleQuotes (text (concatMap charToC s))
922 charToC :: Word8 -> String
924 case chr (fromIntegral w) of
928 c | c >= ' ' && c <= '~' -> [c]
929 | otherwise -> ['\\',
930 chr (ord '0' + ord c `div` 64),
931 chr (ord '0' + ord c `div` 8 `mod` 8),
932 chr (ord '0' + ord c `mod` 8)]
934 -- ---------------------------------------------------------------------------
935 -- Initialising static objects with floating-point numbers. We can't
936 -- just emit the floating point number, because C will cast it to an int
937 -- by rounding it. We want the actual bit-representation of the float.
939 -- This is a hack to turn the floating point numbers into ints that we
940 -- can safely initialise to static locations.
943 | machRepByteWidth F64 == 2 * wORD_SIZE = True
944 | machRepByteWidth F64 == wORD_SIZE = False
945 | otherwise = panic "big_doubles"
947 castFloatToIntArray :: STUArray s Int Float -> ST s (STUArray s Int Int)
948 castFloatToIntArray = castSTUArray
950 castDoubleToIntArray :: STUArray s Int Double -> ST s (STUArray s Int Int)
951 castDoubleToIntArray = castSTUArray
953 -- floats are always 1 word
954 floatToWord :: Rational -> CmmLit
957 arr <- newArray_ ((0::Int),0)
958 writeArray arr 0 (fromRational r)
959 arr' <- castFloatToIntArray arr
960 i <- readArray arr' 0
961 return (CmmInt (toInteger i) wordRep)
964 doubleToWords :: Rational -> [CmmLit]
966 | big_doubles -- doubles are 2 words
968 arr <- newArray_ ((0::Int),1)
969 writeArray arr 0 (fromRational r)
970 arr' <- castDoubleToIntArray arr
971 i1 <- readArray arr' 0
972 i2 <- readArray arr' 1
973 return [ CmmInt (toInteger i1) wordRep
974 , CmmInt (toInteger i2) wordRep
977 | otherwise -- doubles are 1 word
979 arr <- newArray_ ((0::Int),0)
980 writeArray arr 0 (fromRational r)
981 arr' <- castDoubleToIntArray arr
982 i <- readArray arr' 0
983 return [ CmmInt (toInteger i) wordRep ]
986 -- ---------------------------------------------------------------------------
990 wordShift = machRepLogWidth wordRep
992 commafy :: [SDoc] -> SDoc
993 commafy xs = hsep $ punctuate comma xs
995 -- Print in C hex format: 0x13fa
996 pprHexVal :: Integer -> MachRep -> SDoc
997 pprHexVal 0 _ = ptext SLIT("0x0")
999 | w < 0 = parens (char '-' <> ptext SLIT("0x") <> go (-w) <> repsuffix rep)
1000 | otherwise = ptext SLIT("0x") <> go w <> repsuffix rep
1002 -- type suffix for literals:
1003 -- Integer literals are unsigned in Cmm/C. We explicitly cast to
1004 -- signed values for doing signed operations, but at all other
1005 -- times values are unsigned. This also helps eliminate occasional
1006 -- warnings about integer overflow from gcc.
1008 -- on 32-bit platforms, add "ULL" to 64-bit literals
1009 repsuffix I64 | wORD_SIZE == 4 = ptext SLIT("ULL")
1010 -- on 64-bit platforms with 32-bit int, add "L" to 64-bit literals
1011 repsuffix I64 | cINT_SIZE == 4 = ptext SLIT("UL")
1012 repsuffix _ = char 'U'
1017 (q,r) = w' `quotRem` 16
1018 dig | r < 10 = char (chr (fromInteger r + ord '0'))
1019 | otherwise = char (chr (fromInteger r - 10 + ord 'a'))