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 (CmmCallee fn cconv) results args safety _ret ->
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 _ret ->
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 && (off `rem` wORD_SIZE == 0)
326 -- ToDo: check that the offset is a word multiple?
327 -- (For tagging to work, I had to avoid unaligned loads. --ARY)
328 -> pprAsPtrReg r <> brackets (ppr (off `shiftR` wordShift))
334 CmmReg reg -> pprCastReg reg
335 CmmRegOff reg 0 -> pprCastReg reg
338 | i > 0 -> pprRegOff (char '+') i
339 | otherwise -> pprRegOff (char '-') (-i)
341 pprRegOff op i' = pprCastReg reg <> op <> int i'
343 CmmMachOp mop args -> pprMachOpApp mop args
345 pprExpr1 :: CmmExpr -> SDoc
346 pprExpr1 (CmmLit lit) = pprLit1 lit
347 pprExpr1 e@(CmmReg _reg) = pprExpr e
348 pprExpr1 other = parens (pprExpr other)
350 -- --------------------------------------------------------------------------
351 -- MachOp applications
353 pprMachOpApp :: MachOp -> [CmmExpr] -> SDoc
357 = ptext SLIT("mulIntMayOflo") <> parens (commafy (map pprExpr args))
358 where isMulMayOfloOp (MO_U_MulMayOflo _) = True
359 isMulMayOfloOp (MO_S_MulMayOflo _) = True
360 isMulMayOfloOp _ = False
362 pprMachOpApp mop args
363 | Just ty <- machOpNeedsCast mop
364 = ty <> parens (pprMachOpApp' mop args)
366 = pprMachOpApp' mop args
368 -- Comparisons in C have type 'int', but we want type W_ (this is what
369 -- resultRepOfMachOp says). The other C operations inherit their type
370 -- from their operands, so no casting is required.
371 machOpNeedsCast :: MachOp -> Maybe SDoc
373 | isComparisonMachOp mop = Just mkW_
374 | otherwise = Nothing
376 pprMachOpApp' mop args
379 [x,y] -> pprArg x <+> pprMachOp_for_C mop <+> pprArg y
382 [x] -> pprMachOp_for_C mop <> parens (pprArg x)
384 _ -> panic "PprC.pprMachOp : machop with wrong number of args"
387 pprArg e | signedOp mop = cCast (machRepSignedCType (cmmExprRep e)) e
388 | otherwise = pprExpr1 e
390 -- --------------------------------------------------------------------------
393 pprLit :: CmmLit -> SDoc
394 pprLit lit = case lit of
395 CmmInt i rep -> pprHexVal i rep
396 CmmFloat f rep -> parens (machRepCType rep) <> (rational f)
397 CmmLabel clbl -> mkW_ <> pprCLabelAddr clbl
398 CmmLabelOff clbl i -> mkW_ <> pprCLabelAddr clbl <> char '+' <> int i
399 CmmLabelDiffOff clbl1 clbl2 i
401 -- * the lit must occur in the info table clbl2
402 -- * clbl1 must be an SRT, a slow entry point or a large bitmap
403 -- The Mangler is expected to convert any reference to an SRT,
404 -- a slow entry point or a large bitmap
405 -- from an info table to an offset.
406 -> mkW_ <> pprCLabelAddr clbl1 <> char '+' <> int i
408 pprCLabelAddr lbl = char '&' <> pprCLabel lbl
410 pprLit1 :: CmmLit -> SDoc
411 pprLit1 lit@(CmmLabelOff _ _) = parens (pprLit lit)
412 pprLit1 lit@(CmmLabelDiffOff _ _ _) = parens (pprLit lit)
413 pprLit1 lit@(CmmFloat _ _) = parens (pprLit lit)
414 pprLit1 other = pprLit other
416 -- ---------------------------------------------------------------------------
419 pprStatics :: [CmmStatic] -> [SDoc]
421 pprStatics (CmmStaticLit (CmmFloat f F32) : rest)
422 = pprLit1 (floatToWord f) : pprStatics rest
423 pprStatics (CmmStaticLit (CmmFloat f F64) : rest)
424 = map pprLit1 (doubleToWords f) ++ pprStatics rest
425 pprStatics (CmmStaticLit (CmmInt i I64) : rest)
426 | machRepByteWidth I32 == wORD_SIZE
427 #ifdef WORDS_BIGENDIAN
428 = pprStatics (CmmStaticLit (CmmInt q I32) :
429 CmmStaticLit (CmmInt r I32) : rest)
431 = pprStatics (CmmStaticLit (CmmInt r I32) :
432 CmmStaticLit (CmmInt q I32) : rest)
434 where r = i .&. 0xffffffff
436 pprStatics (CmmStaticLit (CmmInt i rep) : rest)
437 | machRepByteWidth rep /= wORD_SIZE
438 = panic "pprStatics: cannot emit a non-word-sized static literal"
439 pprStatics (CmmStaticLit lit : rest)
440 = pprLit1 lit : pprStatics rest
441 pprStatics (other : rest)
442 = pprPanic "pprWord" (pprStatic other)
444 pprStatic :: CmmStatic -> SDoc
445 pprStatic s = case s of
447 CmmStaticLit lit -> nest 4 (pprLit lit)
448 CmmAlign i -> nest 4 (ptext SLIT("/* align */") <+> int i)
449 CmmDataLabel clbl -> pprCLabel clbl <> colon
450 CmmUninitialised i -> nest 4 (mkC_ <> brackets (int i))
452 -- these should be inlined, like the old .hc
453 CmmString s' -> nest 4 (mkW_ <> parens(pprStringInCStyle s'))
456 -- ---------------------------------------------------------------------------
459 pprBlockId :: BlockId -> SDoc
460 pprBlockId b = char '_' <> ppr (getUnique b)
462 -- --------------------------------------------------------------------------
463 -- Print a MachOp in a way suitable for emitting via C.
466 pprMachOp_for_C :: MachOp -> SDoc
468 pprMachOp_for_C mop = case mop of
470 -- Integer operations
473 MO_Eq _ -> ptext SLIT("==")
474 MO_Ne _ -> ptext SLIT("!=")
477 MO_S_Quot _ -> char '/'
478 MO_S_Rem _ -> char '%'
479 MO_S_Neg _ -> char '-'
481 MO_U_Quot _ -> char '/'
482 MO_U_Rem _ -> char '%'
484 -- Signed comparisons (floating-point comparisons also use these)
485 -- & Unsigned comparisons
486 MO_S_Ge _ -> ptext SLIT(">=")
487 MO_S_Le _ -> ptext SLIT("<=")
488 MO_S_Gt _ -> char '>'
489 MO_S_Lt _ -> char '<'
491 MO_U_Ge _ -> ptext SLIT(">=")
492 MO_U_Le _ -> ptext SLIT("<=")
493 MO_U_Gt _ -> char '>'
494 MO_U_Lt _ -> char '<'
496 -- Bitwise operations. Not all of these may be supported at all
497 -- sizes, and only integral MachReps are valid.
502 MO_Shl _ -> ptext SLIT("<<")
503 MO_U_Shr _ -> ptext SLIT(">>") -- unsigned shift right
504 MO_S_Shr _ -> ptext SLIT(">>") -- signed shift right
506 -- Conversions. Some of these will be NOPs.
507 -- Floating-point conversions use the signed variant.
508 -- We won't know to generate (void*) casts here, but maybe from
512 MO_U_Conv I8 I8 -> empty
513 MO_U_Conv I16 I16 -> empty
514 MO_U_Conv I32 I32 -> empty
515 MO_U_Conv I64 I64 -> empty
516 MO_U_Conv I128 I128 -> empty
517 MO_S_Conv I8 I8 -> empty
518 MO_S_Conv I16 I16 -> empty
519 MO_S_Conv I32 I32 -> empty
520 MO_S_Conv I64 I64 -> empty
521 MO_S_Conv I128 I128 -> empty
523 MO_U_Conv _from to -> parens (machRepCType to)
524 MO_S_Conv _from to -> parens (machRepSignedCType to)
526 _ -> panic "PprC.pprMachOp_for_C: unknown machop"
528 signedOp :: MachOp -> Bool
529 signedOp (MO_S_Quot _) = True
530 signedOp (MO_S_Rem _) = True
531 signedOp (MO_S_Neg _) = True
532 signedOp (MO_S_Ge _) = True
533 signedOp (MO_S_Le _) = True
534 signedOp (MO_S_Gt _) = True
535 signedOp (MO_S_Lt _) = True
536 signedOp (MO_S_Shr _) = True
537 signedOp (MO_S_Conv _ _) = True
540 -- ---------------------------------------------------------------------
541 -- tend to be implemented by foreign calls
543 pprCallishMachOp_for_C :: CallishMachOp -> SDoc
545 pprCallishMachOp_for_C mop
547 MO_F64_Pwr -> ptext SLIT("pow")
548 MO_F64_Sin -> ptext SLIT("sin")
549 MO_F64_Cos -> ptext SLIT("cos")
550 MO_F64_Tan -> ptext SLIT("tan")
551 MO_F64_Sinh -> ptext SLIT("sinh")
552 MO_F64_Cosh -> ptext SLIT("cosh")
553 MO_F64_Tanh -> ptext SLIT("tanh")
554 MO_F64_Asin -> ptext SLIT("asin")
555 MO_F64_Acos -> ptext SLIT("acos")
556 MO_F64_Atan -> ptext SLIT("atan")
557 MO_F64_Log -> ptext SLIT("log")
558 MO_F64_Exp -> ptext SLIT("exp")
559 MO_F64_Sqrt -> ptext SLIT("sqrt")
560 MO_F32_Pwr -> ptext SLIT("powf")
561 MO_F32_Sin -> ptext SLIT("sinf")
562 MO_F32_Cos -> ptext SLIT("cosf")
563 MO_F32_Tan -> ptext SLIT("tanf")
564 MO_F32_Sinh -> ptext SLIT("sinhf")
565 MO_F32_Cosh -> ptext SLIT("coshf")
566 MO_F32_Tanh -> ptext SLIT("tanhf")
567 MO_F32_Asin -> ptext SLIT("asinf")
568 MO_F32_Acos -> ptext SLIT("acosf")
569 MO_F32_Atan -> ptext SLIT("atanf")
570 MO_F32_Log -> ptext SLIT("logf")
571 MO_F32_Exp -> ptext SLIT("expf")
572 MO_F32_Sqrt -> ptext SLIT("sqrtf")
573 MO_WriteBarrier -> ptext SLIT("write_barrier")
575 -- ---------------------------------------------------------------------
579 mkJMP_, mkFN_, mkIF_ :: SDoc -> SDoc
581 mkJMP_ i = ptext SLIT("JMP_") <> parens i
582 mkFN_ i = ptext SLIT("FN_") <> parens i -- externally visible function
583 mkIF_ i = ptext SLIT("IF_") <> parens i -- locally visible
587 mkFB_ = ptext SLIT("FB_") -- function code begin
588 mkFE_ = ptext SLIT("FE_") -- function code end
590 -- from includes/Stg.h
592 mkC_,mkW_,mkP_,mkPP_,mkI_,mkA_,mkD_,mkF_,mkB_,mkL_,mkLI_,mkLW_ :: SDoc
594 mkC_ = ptext SLIT("(C_)") -- StgChar
595 mkW_ = ptext SLIT("(W_)") -- StgWord
596 mkP_ = ptext SLIT("(P_)") -- StgWord*
597 mkPP_ = ptext SLIT("(PP_)") -- P_*
598 mkI_ = ptext SLIT("(I_)") -- StgInt
599 mkA_ = ptext SLIT("(A_)") -- StgAddr
600 mkD_ = ptext SLIT("(D_)") -- const StgWord*
601 mkF_ = ptext SLIT("(F_)") -- StgFunPtr
602 mkB_ = ptext SLIT("(B_)") -- StgByteArray
603 mkL_ = ptext SLIT("(L_)") -- StgClosurePtr
605 mkLI_ = ptext SLIT("(LI_)") -- StgInt64
606 mkLW_ = ptext SLIT("(LW_)") -- StgWord64
609 -- ---------------------------------------------------------------------
613 -- Generating assignments is what we're all about, here
615 pprAssign :: CmmReg -> CmmExpr -> SDoc
617 -- dest is a reg, rhs is a reg
618 pprAssign r1 (CmmReg r2)
619 | isPtrReg r1 && isPtrReg r2
620 = hcat [ pprAsPtrReg r1, equals, pprAsPtrReg r2, semi ]
622 -- dest is a reg, rhs is a CmmRegOff
623 pprAssign r1 (CmmRegOff r2 off)
624 | isPtrReg r1 && isPtrReg r2 && (off `rem` wORD_SIZE == 0)
625 = hcat [ pprAsPtrReg r1, equals, pprAsPtrReg r2, op, int off', semi ]
627 off1 = off `shiftR` wordShift
629 (op,off') | off >= 0 = (char '+', off1)
630 | otherwise = (char '-', -off1)
632 -- dest is a reg, rhs is anything.
633 -- We can't cast the lvalue, so we have to cast the rhs if necessary. Casting
634 -- the lvalue elicits a warning from new GCC versions (3.4+).
636 | isFixedPtrReg r1 = mkAssign (mkP_ <> pprExpr1 r2)
637 | Just ty <- strangeRegType r1 = mkAssign (parens ty <> pprExpr1 r2)
638 | otherwise = mkAssign (pprExpr r2)
639 where mkAssign x = if r1 == CmmGlobal BaseReg
640 then ptext SLIT("ASSIGN_BaseReg") <> parens x <> semi
641 else pprReg r1 <> ptext SLIT(" = ") <> x <> semi
643 -- ---------------------------------------------------------------------
647 | isStrangeTypeReg reg = mkW_ <> pprReg reg
648 | otherwise = pprReg reg
650 -- True if (pprReg reg) will give an expression with type StgPtr. We
651 -- need to take care with pointer arithmetic on registers with type
653 isFixedPtrReg :: CmmReg -> Bool
654 isFixedPtrReg (CmmLocal _) = False
655 isFixedPtrReg (CmmGlobal r) = isFixedPtrGlobalReg r
657 -- True if (pprAsPtrReg reg) will give an expression with type StgPtr
658 isPtrReg :: CmmReg -> Bool
659 isPtrReg (CmmLocal _) = False
660 isPtrReg (CmmGlobal (VanillaReg n)) = True -- if we print via pprAsPtrReg
661 isPtrReg (CmmGlobal reg) = isFixedPtrGlobalReg reg
663 -- True if this global reg has type StgPtr
664 isFixedPtrGlobalReg :: GlobalReg -> Bool
665 isFixedPtrGlobalReg Sp = True
666 isFixedPtrGlobalReg Hp = True
667 isFixedPtrGlobalReg HpLim = True
668 isFixedPtrGlobalReg SpLim = True
669 isFixedPtrGlobalReg _ = False
671 -- True if in C this register doesn't have the type given by
672 -- (machRepCType (cmmRegRep reg)), so it has to be cast.
673 isStrangeTypeReg :: CmmReg -> Bool
674 isStrangeTypeReg (CmmLocal _) = False
675 isStrangeTypeReg (CmmGlobal g) = isStrangeTypeGlobal g
677 isStrangeTypeGlobal :: GlobalReg -> Bool
678 isStrangeTypeGlobal CurrentTSO = True
679 isStrangeTypeGlobal CurrentNursery = True
680 isStrangeTypeGlobal BaseReg = True
681 isStrangeTypeGlobal r = isFixedPtrGlobalReg r
683 strangeRegType :: CmmReg -> Maybe SDoc
684 strangeRegType (CmmGlobal CurrentTSO) = Just (ptext SLIT("struct StgTSO_ *"))
685 strangeRegType (CmmGlobal CurrentNursery) = Just (ptext SLIT("struct bdescr_ *"))
686 strangeRegType (CmmGlobal BaseReg) = Just (ptext SLIT("struct StgRegTable_ *"))
687 strangeRegType _ = Nothing
689 -- pprReg just prints the register name.
691 pprReg :: CmmReg -> SDoc
693 CmmLocal local -> pprLocalReg local
694 CmmGlobal global -> pprGlobalReg global
696 pprAsPtrReg :: CmmReg -> SDoc
697 pprAsPtrReg (CmmGlobal (VanillaReg n)) = char 'R' <> int n <> ptext SLIT(".p")
698 pprAsPtrReg other_reg = pprReg other_reg
700 pprGlobalReg :: GlobalReg -> SDoc
701 pprGlobalReg gr = case gr of
702 VanillaReg n -> char 'R' <> int n <> ptext SLIT(".w")
703 FloatReg n -> char 'F' <> int n
704 DoubleReg n -> char 'D' <> int n
705 LongReg n -> char 'L' <> int n
706 Sp -> ptext SLIT("Sp")
707 SpLim -> ptext SLIT("SpLim")
708 Hp -> ptext SLIT("Hp")
709 HpLim -> ptext SLIT("HpLim")
710 CurrentTSO -> ptext SLIT("CurrentTSO")
711 CurrentNursery -> ptext SLIT("CurrentNursery")
712 HpAlloc -> ptext SLIT("HpAlloc")
713 BaseReg -> ptext SLIT("BaseReg")
714 GCEnter1 -> ptext SLIT("stg_gc_enter_1")
715 GCFun -> ptext SLIT("stg_gc_fun")
717 pprLocalReg :: LocalReg -> SDoc
718 pprLocalReg (LocalReg uniq _ _) = char '_' <> ppr uniq
720 -- -----------------------------------------------------------------------------
723 pprCall :: SDoc -> CCallConv -> CmmHintFormals -> CmmActuals -> CmmSafety
726 pprCall ppr_fn cconv results args _
727 | not (is_cish cconv)
728 = panic "pprCall: unknown calling convention"
732 #if x86_64_TARGET_ARCH
733 -- HACK around gcc optimisations.
734 -- x86_64 needs a __DISCARD__() here, to create a barrier between
735 -- putting the arguments into temporaries and passing the arguments
736 -- to the callee, because the argument expressions may refer to
737 -- machine registers that are also used for passing arguments in the
738 -- C calling convention.
739 (if (not opt_Unregisterised)
740 then ptext SLIT("__DISCARD__();")
743 ppr_assign results (ppr_fn <> parens (commafy (map pprArg args))) <> semi
745 ppr_assign [] rhs = rhs
746 ppr_assign [(one,hint)] rhs
747 = pprLocalReg one <> ptext SLIT(" = ")
748 <> pprUnHint hint (localRegRep one) <> rhs
749 ppr_assign _other _rhs = panic "pprCall: multiple results"
751 pprArg (expr, PtrHint)
752 = cCast (ptext SLIT("void *")) expr
753 -- see comment by machRepHintCType below
754 pprArg (expr, SignedHint)
755 = cCast (machRepSignedCType (cmmExprRep expr)) expr
756 pprArg (expr, _other)
759 pprUnHint PtrHint rep = parens (machRepCType rep)
760 pprUnHint SignedHint rep = parens (machRepCType rep)
761 pprUnHint _ _ = empty
763 pprGlobalRegName :: GlobalReg -> SDoc
764 pprGlobalRegName gr = case gr of
765 VanillaReg n -> char 'R' <> int n -- without the .w suffix
768 -- Currently we only have these two calling conventions, but this might
769 -- change in the future...
770 is_cish CCallConv = True
771 is_cish StdCallConv = True
773 -- ---------------------------------------------------------------------
774 -- Find and print local and external declarations for a list of
777 pprTempAndExternDecls :: [CmmBasicBlock] -> (SDoc{-temps-}, SDoc{-externs-})
778 pprTempAndExternDecls stmts
779 = (vcat (map pprTempDecl (eltsUFM temps)),
780 vcat (map (pprExternDecl False{-ToDo-}) (keysFM lbls)))
781 where (temps, lbls) = runTE (mapM_ te_BB stmts)
783 pprDataExterns :: [CmmStatic] -> SDoc
784 pprDataExterns statics
785 = vcat (map (pprExternDecl False{-ToDo-}) (keysFM lbls))
786 where (_, lbls) = runTE (mapM_ te_Static statics)
788 pprTempDecl :: LocalReg -> SDoc
789 pprTempDecl l@(LocalReg _ rep _)
790 = hcat [ machRepCType rep, space, pprLocalReg l, semi ]
792 pprExternDecl :: Bool -> CLabel -> SDoc
793 pprExternDecl in_srt lbl
794 -- do not print anything for "known external" things
795 | not (needsCDecl lbl) = empty
797 hcat [ visibility, label_type (labelType lbl),
798 lparen, pprCLabel lbl, text ");" ]
800 label_type CodeLabel = ptext SLIT("F_")
801 label_type DataLabel = ptext SLIT("I_")
804 | externallyVisibleCLabel lbl = char 'E'
805 | otherwise = char 'I'
808 type TEState = (UniqSet LocalReg, FiniteMap CLabel ())
809 newtype TE a = TE { unTE :: TEState -> (a, TEState) }
811 instance Monad TE where
812 TE m >>= k = TE $ \s -> case m s of (a, s') -> unTE (k a) s'
813 return a = TE $ \s -> (a, s)
815 te_lbl :: CLabel -> TE ()
816 te_lbl lbl = TE $ \(temps,lbls) -> ((), (temps, addToFM lbls lbl ()))
818 te_temp :: LocalReg -> TE ()
819 te_temp r = TE $ \(temps,lbls) -> ((), (addOneToUniqSet temps r, lbls))
821 runTE :: TE () -> TEState
822 runTE (TE m) = snd (m (emptyUniqSet, emptyFM))
824 te_Static :: CmmStatic -> TE ()
825 te_Static (CmmStaticLit lit) = te_Lit lit
826 te_Static _ = return ()
828 te_BB :: CmmBasicBlock -> TE ()
829 te_BB (BasicBlock _ ss) = mapM_ te_Stmt ss
831 te_Lit :: CmmLit -> TE ()
832 te_Lit (CmmLabel l) = te_lbl l
833 te_Lit (CmmLabelOff l _) = te_lbl l
834 te_Lit (CmmLabelDiffOff l1 l2 _) = te_lbl l1
837 te_Stmt :: CmmStmt -> TE ()
838 te_Stmt (CmmAssign r e) = te_Reg r >> te_Expr e
839 te_Stmt (CmmStore l r) = te_Expr l >> te_Expr r
840 te_Stmt (CmmCall _ rs es _ _) = mapM_ (te_temp.fst) rs >>
841 mapM_ (te_Expr.fst) es
842 te_Stmt (CmmCondBranch e _) = te_Expr e
843 te_Stmt (CmmSwitch e _) = te_Expr e
844 te_Stmt (CmmJump e _) = te_Expr e
845 te_Stmt _ = return ()
847 te_Expr :: CmmExpr -> TE ()
848 te_Expr (CmmLit lit) = te_Lit lit
849 te_Expr (CmmLoad e _) = te_Expr e
850 te_Expr (CmmReg r) = te_Reg r
851 te_Expr (CmmMachOp _ es) = mapM_ te_Expr es
852 te_Expr (CmmRegOff r _) = te_Reg r
854 te_Reg :: CmmReg -> TE ()
855 te_Reg (CmmLocal l) = te_temp l
859 -- ---------------------------------------------------------------------
860 -- C types for MachReps
862 cCast :: SDoc -> CmmExpr -> SDoc
863 cCast ty expr = parens ty <> pprExpr1 expr
865 cLoad :: CmmExpr -> MachRep -> SDoc
866 #ifdef BEWARE_LOAD_STORE_ALIGNMENT
868 let decl = machRepCType rep <+> ptext SLIT("x") <> semi
869 struct = ptext SLIT("struct") <+> braces (decl)
870 packed_attr = ptext SLIT("__attribute__((packed))")
871 cast = parens (struct <+> packed_attr <> char '*')
872 in parens (cast <+> pprExpr1 expr) <> ptext SLIT("->x")
874 cLoad expr rep = char '*' <> parens (cCast (machRepPtrCType rep) expr)
877 -- This is for finding the types of foreign call arguments. For a pointer
878 -- argument, we always cast the argument to (void *), to avoid warnings from
880 machRepHintCType :: MachRep -> MachHint -> SDoc
881 machRepHintCType rep PtrHint = ptext SLIT("void *")
882 machRepHintCType rep SignedHint = machRepSignedCType rep
883 machRepHintCType rep _other = machRepCType rep
885 machRepPtrCType :: MachRep -> SDoc
886 machRepPtrCType r | r == wordRep = ptext SLIT("P_")
887 | otherwise = machRepCType r <> char '*'
889 machRepCType :: MachRep -> SDoc
890 machRepCType r | r == wordRep = ptext SLIT("W_")
891 | otherwise = sized_type
892 where sized_type = case r of
893 I8 -> ptext SLIT("StgWord8")
894 I16 -> ptext SLIT("StgWord16")
895 I32 -> ptext SLIT("StgWord32")
896 I64 -> ptext SLIT("StgWord64")
897 F32 -> ptext SLIT("StgFloat") -- ToDo: correct?
898 F64 -> ptext SLIT("StgDouble")
899 _ -> panic "machRepCType"
901 machRepSignedCType :: MachRep -> SDoc
902 machRepSignedCType r | r == wordRep = ptext SLIT("I_")
903 | otherwise = sized_type
904 where sized_type = case r of
905 I8 -> ptext SLIT("StgInt8")
906 I16 -> ptext SLIT("StgInt16")
907 I32 -> ptext SLIT("StgInt32")
908 I64 -> ptext SLIT("StgInt64")
909 F32 -> ptext SLIT("StgFloat") -- ToDo: correct?
910 F64 -> ptext SLIT("StgDouble")
911 _ -> panic "machRepCType"
913 -- ---------------------------------------------------------------------
914 -- print strings as valid C strings
916 pprStringInCStyle :: [Word8] -> SDoc
917 pprStringInCStyle s = doubleQuotes (text (concatMap charToC s))
919 charToC :: Word8 -> String
921 case chr (fromIntegral w) of
925 c | c >= ' ' && c <= '~' -> [c]
926 | otherwise -> ['\\',
927 chr (ord '0' + ord c `div` 64),
928 chr (ord '0' + ord c `div` 8 `mod` 8),
929 chr (ord '0' + ord c `mod` 8)]
931 -- ---------------------------------------------------------------------------
932 -- Initialising static objects with floating-point numbers. We can't
933 -- just emit the floating point number, because C will cast it to an int
934 -- by rounding it. We want the actual bit-representation of the float.
936 -- This is a hack to turn the floating point numbers into ints that we
937 -- can safely initialise to static locations.
940 | machRepByteWidth F64 == 2 * wORD_SIZE = True
941 | machRepByteWidth F64 == wORD_SIZE = False
942 | otherwise = panic "big_doubles"
944 castFloatToIntArray :: STUArray s Int Float -> ST s (STUArray s Int Int)
945 castFloatToIntArray = castSTUArray
947 castDoubleToIntArray :: STUArray s Int Double -> ST s (STUArray s Int Int)
948 castDoubleToIntArray = castSTUArray
950 -- floats are always 1 word
951 floatToWord :: Rational -> CmmLit
954 arr <- newArray_ ((0::Int),0)
955 writeArray arr 0 (fromRational r)
956 arr' <- castFloatToIntArray arr
957 i <- readArray arr' 0
958 return (CmmInt (toInteger i) wordRep)
961 doubleToWords :: Rational -> [CmmLit]
963 | big_doubles -- doubles are 2 words
965 arr <- newArray_ ((0::Int),1)
966 writeArray arr 0 (fromRational r)
967 arr' <- castDoubleToIntArray arr
968 i1 <- readArray arr' 0
969 i2 <- readArray arr' 1
970 return [ CmmInt (toInteger i1) wordRep
971 , CmmInt (toInteger i2) wordRep
974 | otherwise -- doubles are 1 word
976 arr <- newArray_ ((0::Int),0)
977 writeArray arr 0 (fromRational r)
978 arr' <- castDoubleToIntArray arr
979 i <- readArray arr' 0
980 return [ CmmInt (toInteger i) wordRep ]
983 -- ---------------------------------------------------------------------------
987 wordShift = machRepLogWidth wordRep
989 commafy :: [SDoc] -> SDoc
990 commafy xs = hsep $ punctuate comma xs
992 -- Print in C hex format: 0x13fa
993 pprHexVal :: Integer -> MachRep -> SDoc
994 pprHexVal 0 _ = ptext SLIT("0x0")
996 | w < 0 = parens (char '-' <> ptext SLIT("0x") <> go (-w) <> repsuffix rep)
997 | otherwise = ptext SLIT("0x") <> go w <> repsuffix rep
999 -- type suffix for literals:
1000 -- Integer literals are unsigned in Cmm/C. We explicitly cast to
1001 -- signed values for doing signed operations, but at all other
1002 -- times values are unsigned. This also helps eliminate occasional
1003 -- warnings about integer overflow from gcc.
1005 -- on 32-bit platforms, add "ULL" to 64-bit literals
1006 repsuffix I64 | wORD_SIZE == 4 = ptext SLIT("ULL")
1007 -- on 64-bit platforms with 32-bit int, add "L" to 64-bit literals
1008 repsuffix I64 | cINT_SIZE == 4 = ptext SLIT("UL")
1009 repsuffix _ = char 'U'
1014 (q,r) = w' `quotRem` 16
1015 dig | r < 10 = char (chr (fromInteger r + ord '0'))
1016 | otherwise = char (chr (fromInteger r - 10 + ord 'a'))