2 -- The above warning supression flag is a temporary kludge.
3 -- While working on this module you are encouraged to remove it and fix
4 -- any warnings in the module. See
5 -- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
8 -----------------------------------------------------------------------------
10 -- Pretty-printing of Cmm as C, suitable for feeding gcc
12 -- (c) The University of Glasgow 2004-2006
14 -----------------------------------------------------------------------------
17 -- Print Cmm as real C, for -fvia-C
19 -- See wiki:Commentary/Compiler/Backends/PprC
21 -- This is simpler than the old PprAbsC, because Cmm is "macro-expanded"
22 -- relative to the old AbstractC, and many oddities/decorations have
23 -- disappeared from the data type.
26 -- ToDo: save/restore volatile registers around calls.
33 #include "HsVersions.h"
38 import PprCmm () -- Instances only
61 import Control.Monad.ST
63 #if x86_64_TARGET_ARCH
64 import StaticFlags ( opt_Unregisterised )
67 #if defined(alpha_TARGET_ARCH) || defined(mips_TARGET_ARCH) || defined(mipsel_TARGET_ARCH) || defined(arm_TARGET_ARCH)
68 #define BEWARE_LOAD_STORE_ALIGNMENT
71 -- --------------------------------------------------------------------------
74 pprCs :: DynFlags -> [RawCmm] -> SDoc
76 = pprCode CStyle (vcat $ map (\c -> split_marker $$ pprC c) cmms)
79 | dopt Opt_SplitObjs dflags = ptext (sLit "__STG_SPLIT_MARKER")
82 writeCs :: DynFlags -> Handle -> [RawCmm] -> IO ()
83 writeCs dflags handle cmms
84 = printForC handle (pprCs dflags cmms)
86 -- --------------------------------------------------------------------------
87 -- Now do some real work
89 -- for fun, we could call cmmToCmm over the tops...
92 pprC :: RawCmm -> SDoc
93 pprC (Cmm tops) = vcat $ intersperse (text "") $ map pprTop tops
98 pprTop :: RawCmmTop -> SDoc
99 pprTop (CmmProc info clbl _params (ListGraph blocks)) =
101 then pprDataExterns info $$
102 pprWordArray (entryLblToInfoLbl clbl) info
106 -- the first block doesn't get a label:
107 (BasicBlock _ stmts : rest) -> vcat [
110 (if (externallyVisibleCLabel clbl)
111 then mkFN_ else mkIF_) (pprCLabel clbl) <+> lbrace,
114 nest 8 (vcat (map pprStmt stmts)) $$
115 vcat (map pprBBlock rest),
120 (temp_decls, extern_decls) = pprTempAndExternDecls blocks
123 -- Chunks of static data.
125 -- We only handle (a) arrays of word-sized things and (b) strings.
127 pprTop (CmmData _section _ds@[CmmDataLabel lbl, CmmString str]) =
129 pprLocalness lbl, ptext (sLit "char "), pprCLabel lbl,
130 ptext (sLit "[] = "), pprStringInCStyle str, semi
133 pprTop (CmmData _section _ds@[CmmDataLabel lbl, CmmUninitialised size]) =
135 pprLocalness lbl, ptext (sLit "char "), pprCLabel lbl,
136 brackets (int size), semi
139 pprTop top@(CmmData _section (CmmDataLabel lbl : lits)) =
140 pprDataExterns lits $$
141 pprWordArray lbl lits
143 -- Floating info table for safe a foreign call.
144 pprTop top@(CmmData _section d@(_ : _))
145 | CmmDataLabel lbl : lits <- reverse d =
146 let lits' = reverse lits
147 in pprDataExterns lits' $$
148 pprWordArray lbl lits'
150 -- these shouldn't appear?
151 pprTop (CmmData _ _) = panic "PprC.pprTop: can't handle this data"
153 -- --------------------------------------------------------------------------
154 -- BasicBlocks are self-contained entities: they always end in a jump.
156 -- Like nativeGen/AsmCodeGen, we could probably reorder blocks to turn
157 -- as many jumps as possible into fall throughs.
160 pprBBlock :: CmmBasicBlock -> SDoc
161 pprBBlock (BasicBlock lbl stmts) =
163 pprTrace "pprC.pprBBlock: curious empty code block for"
164 (pprBlockId lbl) empty
166 nest 4 (pprBlockId lbl <> colon) $$
167 nest 8 (vcat (map pprStmt stmts))
169 -- --------------------------------------------------------------------------
170 -- Info tables. Just arrays of words.
171 -- See codeGen/ClosureInfo, and nativeGen/PprMach
173 pprWordArray :: CLabel -> [CmmStatic] -> SDoc
175 = hcat [ pprLocalness lbl, ptext (sLit "StgWord")
176 , space, pprCLabel lbl, ptext (sLit "[] = {") ]
177 $$ nest 8 (commafy (pprStatics ds))
181 -- has to be static, if it isn't globally visible
183 pprLocalness :: CLabel -> SDoc
184 pprLocalness lbl | not $ externallyVisibleCLabel lbl = ptext (sLit "static ")
187 -- --------------------------------------------------------------------------
191 pprStmt :: CmmStmt -> SDoc
193 pprStmt stmt = case stmt of
195 CmmComment s -> empty -- (hang (ptext (sLit "/*")) 3 (ftext s)) $$ ptext (sLit "*/")
196 -- XXX if the string contains "*/", we need to fix it
197 -- XXX we probably want to emit these comments when
198 -- some debugging option is on. They can get quite
201 CmmAssign dest src -> pprAssign dest src
204 | typeWidth rep == W64 && wordWidth /= W64
205 -> (if isFloatType rep then ptext (sLit "ASSIGN_DBL")
206 else ptext (sLit ("ASSIGN_Word64"))) <>
207 parens (mkP_ <> pprExpr1 dest <> comma <> pprExpr src) <> semi
210 -> hsep [ pprExpr (CmmLoad dest rep), equals, pprExpr src <> semi ]
212 rep = cmmExprType src
214 CmmCall (CmmCallee fn cconv) results args safety ret ->
216 pprCall ppr_fn cconv results args safety
218 cast_fn = parens (cCast (pprCFunType (char '*') cconv results args) fn)
220 real_fun_proto lbl = char ';' <>
221 pprCFunType (pprCLabel lbl) cconv results args <>
222 noreturn_attr <> semi
224 data_proto lbl = ptext (sLit ";EI_(") <>
225 pprCLabel lbl <> char ')' <> semi
227 noreturn_attr = case ret of
228 CmmNeverReturns -> text "__attribute__ ((noreturn))"
229 CmmMayReturn -> empty
231 -- See wiki:Commentary/Compiler/Backends/PprC#Prototypes
232 (maybe_proto, ppr_fn) =
234 CmmLit (CmmLabel lbl)
235 | StdCallConv <- cconv -> (real_fun_proto lbl, pprCLabel lbl)
236 -- stdcall functions must be declared with
237 -- a function type, otherwise the C compiler
238 -- doesn't add the @n suffix to the label. We
239 -- can't add the @n suffix ourselves, because
241 | CmmNeverReturns <- ret -> (real_fun_proto lbl, pprCLabel lbl)
242 | not (isMathFun lbl) -> (data_proto lbl, cast_fn)
243 -- we declare all other called functions as
244 -- data labels, and then cast them to the
245 -- right type when calling. This is because
246 -- the label might already have a declaration
247 -- as a data label in the same file,
248 -- e.g. Foreign.Marshal.Alloc declares 'free'
249 -- as both a data label and a function label.
251 (empty {- no proto -}, cast_fn)
252 -- for a dynamic call, no declaration is necessary.
254 CmmCall (CmmPrim op) results args safety _ret ->
255 pprCall ppr_fn CCallConv results args safety
257 ppr_fn = pprCallishMachOp_for_C op
259 CmmBranch ident -> pprBranch ident
260 CmmCondBranch expr ident -> pprCondBranch expr ident
261 CmmJump lbl _params -> mkJMP_(pprExpr lbl) <> semi
262 CmmSwitch arg ids -> pprSwitch arg ids
264 pprCFunType :: SDoc -> CCallConv -> HintedCmmFormals -> HintedCmmActuals -> SDoc
265 pprCFunType ppr_fn cconv ress args
267 parens (text (ccallConvAttribute cconv) <> ppr_fn) <>
268 parens (commafy (map arg_type args))
270 res_type [] = ptext (sLit "void")
271 res_type [CmmHinted one hint] = machRepHintCType (localRegType one) hint
273 arg_type (CmmHinted expr hint) = machRepHintCType (cmmExprType expr) hint
275 -- ---------------------------------------------------------------------
276 -- unconditional branches
277 pprBranch :: BlockId -> SDoc
278 pprBranch ident = ptext (sLit "goto") <+> pprBlockId ident <> semi
281 -- ---------------------------------------------------------------------
282 -- conditional branches to local labels
283 pprCondBranch :: CmmExpr -> BlockId -> SDoc
284 pprCondBranch expr ident
285 = hsep [ ptext (sLit "if") , parens(pprExpr expr) ,
286 ptext (sLit "goto") , (pprBlockId ident) <> semi ]
289 -- ---------------------------------------------------------------------
290 -- a local table branch
292 -- we find the fall-through cases
294 -- N.B. we remove Nothing's from the list of branches, as they are
295 -- 'undefined'. However, they may be defined one day, so we better
296 -- document this behaviour.
298 pprSwitch :: CmmExpr -> [ Maybe BlockId ] -> SDoc
299 pprSwitch e maybe_ids
300 = let pairs = [ (ix, ident) | (ix,Just ident) <- zip [0..] maybe_ids ]
301 pairs2 = [ (map fst as, snd (head as)) | as <- groupBy sndEq pairs ]
303 (hang (ptext (sLit "switch") <+> parens ( pprExpr e ) <+> lbrace)
304 4 (vcat ( map caseify pairs2 )))
308 sndEq (_,x) (_,y) = x == y
311 caseify (ix:ixs, ident) = vcat (map do_fallthrough ixs) $$ final_branch ix
314 hsep [ ptext (sLit "case") , pprHexVal ix wordWidth <> colon ,
315 ptext (sLit "/* fall through */") ]
318 hsep [ ptext (sLit "case") , pprHexVal ix wordWidth <> colon ,
319 ptext (sLit "goto") , (pprBlockId ident) <> semi ]
321 -- ---------------------------------------------------------------------
325 -- C Types: the invariant is that the C expression generated by
329 -- has a type in C which is also given by
331 -- machRepCType (cmmExprType e)
333 -- (similar invariants apply to the rest of the pretty printer).
335 pprExpr :: CmmExpr -> SDoc
336 pprExpr e = case e of
337 CmmLit lit -> pprLit lit
340 CmmLoad e ty -> pprLoad e ty
341 CmmReg reg -> pprCastReg reg
342 CmmRegOff reg 0 -> pprCastReg reg
345 | i > 0 -> pprRegOff (char '+') i
346 | otherwise -> pprRegOff (char '-') (-i)
348 pprRegOff op i' = pprCastReg reg <> op <> int i'
350 CmmMachOp mop args -> pprMachOpApp mop args
353 pprLoad :: CmmExpr -> CmmType -> SDoc
355 | width == W64, wordWidth /= W64
356 = (if isFloatType ty then ptext (sLit "PK_DBL")
357 else ptext (sLit "PK_Word64"))
358 <> parens (mkP_ <> pprExpr1 e)
362 CmmReg r | isPtrReg r && width == wordWidth && not (isFloatType ty)
363 -> char '*' <> pprAsPtrReg r
365 CmmRegOff r 0 | isPtrReg r && width == wordWidth && not (isFloatType ty)
366 -> char '*' <> pprAsPtrReg r
368 CmmRegOff r off | isPtrReg r && width == wordWidth
369 , off `rem` wORD_SIZE == 0 && not (isFloatType ty)
370 -- ToDo: check that the offset is a word multiple?
371 -- (For tagging to work, I had to avoid unaligned loads. --ARY)
372 -> pprAsPtrReg r <> brackets (ppr (off `shiftR` wordShift))
378 pprExpr1 :: CmmExpr -> SDoc
379 pprExpr1 (CmmLit lit) = pprLit1 lit
380 pprExpr1 e@(CmmReg _reg) = pprExpr e
381 pprExpr1 other = parens (pprExpr other)
383 -- --------------------------------------------------------------------------
384 -- MachOp applications
386 pprMachOpApp :: MachOp -> [CmmExpr] -> SDoc
390 = ptext (sLit "mulIntMayOflo") <> parens (commafy (map pprExpr args))
391 where isMulMayOfloOp (MO_U_MulMayOflo _) = True
392 isMulMayOfloOp (MO_S_MulMayOflo _) = True
393 isMulMayOfloOp _ = False
395 pprMachOpApp mop args
396 | Just ty <- machOpNeedsCast mop
397 = ty <> parens (pprMachOpApp' mop args)
399 = pprMachOpApp' mop args
401 -- Comparisons in C have type 'int', but we want type W_ (this is what
402 -- resultRepOfMachOp says). The other C operations inherit their type
403 -- from their operands, so no casting is required.
404 machOpNeedsCast :: MachOp -> Maybe SDoc
406 | isComparisonMachOp mop = Just mkW_
407 | otherwise = Nothing
409 pprMachOpApp' mop args
412 [x,y] -> pprArg x <+> pprMachOp_for_C mop <+> pprArg y
415 [x] -> pprMachOp_for_C mop <> parens (pprArg x)
417 _ -> panic "PprC.pprMachOp : machop with wrong number of args"
420 -- Cast needed for signed integer ops
421 pprArg e | signedOp mop = cCast (machRep_S_CType (typeWidth (cmmExprType e))) e
422 | needsFCasts mop = cCast (machRep_F_CType (typeWidth (cmmExprType e))) e
423 | otherwise = pprExpr1 e
424 needsFCasts (MO_F_Eq _) = False
425 needsFCasts (MO_F_Ne _) = False
426 needsFCasts (MO_F_Neg _) = True
427 needsFCasts (MO_F_Quot _) = True
428 needsFCasts mop = floatComparison mop
430 -- --------------------------------------------------------------------------
433 pprLit :: CmmLit -> SDoc
434 pprLit lit = case lit of
435 CmmInt i rep -> pprHexVal i rep
437 CmmFloat f w -> parens (machRep_F_CType w) <> str
438 where d = fromRational f :: Double
439 str | isInfinite d && d < 0 = ptext (sLit "-INFINITY")
440 | isInfinite d = ptext (sLit "INFINITY")
441 | isNaN d = ptext (sLit "NAN")
442 | otherwise = text (show d)
443 -- these constants come from <math.h>
446 CmmBlock bid -> mkW_ <> pprCLabelAddr (infoTblLbl bid)
447 CmmHighStackMark -> panic "PprC printing high stack mark"
448 CmmLabel clbl -> mkW_ <> pprCLabelAddr clbl
449 CmmLabelOff clbl i -> mkW_ <> pprCLabelAddr clbl <> char '+' <> int i
450 CmmLabelDiffOff clbl1 clbl2 i
452 -- * the lit must occur in the info table clbl2
453 -- * clbl1 must be an SRT, a slow entry point or a large bitmap
454 -- The Mangler is expected to convert any reference to an SRT,
455 -- a slow entry point or a large bitmap
456 -- from an info table to an offset.
457 -> mkW_ <> pprCLabelAddr clbl1 <> char '+' <> int i
459 pprCLabelAddr lbl = char '&' <> pprCLabel lbl
461 pprLit1 :: CmmLit -> SDoc
462 pprLit1 lit@(CmmLabelOff _ _) = parens (pprLit lit)
463 pprLit1 lit@(CmmLabelDiffOff _ _ _) = parens (pprLit lit)
464 pprLit1 lit@(CmmFloat _ _) = parens (pprLit lit)
465 pprLit1 other = pprLit other
467 -- ---------------------------------------------------------------------------
470 pprStatics :: [CmmStatic] -> [SDoc]
472 pprStatics (CmmStaticLit (CmmFloat f W32) : rest)
473 -- floats are padded to a word, see #1852
474 | wORD_SIZE == 8, CmmStaticLit (CmmInt 0 W32) : rest' <- rest
475 = pprLit1 (floatToWord f) : pprStatics rest'
477 = pprLit1 (floatToWord f) : pprStatics rest
479 = pprPanic "pprStatics: float" (vcat (map (\(CmmStaticLit l) -> ppr (cmmLitType l)) rest))
480 pprStatics (CmmStaticLit (CmmFloat f W64) : rest)
481 = map pprLit1 (doubleToWords f) ++ pprStatics rest
482 pprStatics (CmmStaticLit (CmmInt i W64) : rest)
484 #ifdef WORDS_BIGENDIAN
485 = pprStatics (CmmStaticLit (CmmInt q W32) :
486 CmmStaticLit (CmmInt r W32) : rest)
488 = pprStatics (CmmStaticLit (CmmInt r W32) :
489 CmmStaticLit (CmmInt q W32) : rest)
491 where r = i .&. 0xffffffff
493 pprStatics (CmmStaticLit (CmmInt i w) : rest)
495 = panic "pprStatics: cannot emit a non-word-sized static literal"
496 pprStatics (CmmStaticLit lit : rest)
497 = pprLit1 lit : pprStatics rest
498 pprStatics (other : rest)
499 = pprPanic "pprWord" (pprStatic other)
501 pprStatic :: CmmStatic -> SDoc
502 pprStatic s = case s of
504 CmmStaticLit lit -> nest 4 (pprLit lit)
505 CmmAlign i -> nest 4 (ptext (sLit "/* align */") <+> int i)
506 CmmDataLabel clbl -> pprCLabel clbl <> colon
507 CmmUninitialised i -> nest 4 (mkC_ <> brackets (int i))
509 -- these should be inlined, like the old .hc
510 CmmString s' -> nest 4 (mkW_ <> parens(pprStringInCStyle s'))
513 -- ---------------------------------------------------------------------------
516 pprBlockId :: BlockId -> SDoc
517 pprBlockId b = char '_' <> ppr (getUnique b)
519 -- --------------------------------------------------------------------------
520 -- Print a MachOp in a way suitable for emitting via C.
523 pprMachOp_for_C :: MachOp -> SDoc
525 pprMachOp_for_C mop = case mop of
527 -- Integer operations
530 MO_Eq _ -> ptext (sLit "==")
531 MO_Ne _ -> ptext (sLit "!=")
534 MO_S_Quot _ -> char '/'
535 MO_S_Rem _ -> char '%'
536 MO_S_Neg _ -> char '-'
538 MO_U_Quot _ -> char '/'
539 MO_U_Rem _ -> char '%'
541 -- & Floating-point operations
542 MO_F_Add _ -> char '+'
543 MO_F_Sub _ -> char '-'
544 MO_F_Neg _ -> char '-'
545 MO_F_Mul _ -> char '*'
546 MO_F_Quot _ -> char '/'
548 -- Signed comparisons
549 MO_S_Ge _ -> ptext (sLit ">=")
550 MO_S_Le _ -> ptext (sLit "<=")
551 MO_S_Gt _ -> char '>'
552 MO_S_Lt _ -> char '<'
554 -- & Unsigned comparisons
555 MO_U_Ge _ -> ptext (sLit ">=")
556 MO_U_Le _ -> ptext (sLit "<=")
557 MO_U_Gt _ -> char '>'
558 MO_U_Lt _ -> char '<'
560 -- & Floating-point comparisons
561 MO_F_Eq _ -> ptext (sLit "==")
562 MO_F_Ne _ -> ptext (sLit "!=")
563 MO_F_Ge _ -> ptext (sLit ">=")
564 MO_F_Le _ -> ptext (sLit "<=")
565 MO_F_Gt _ -> char '>'
566 MO_F_Lt _ -> char '<'
568 -- Bitwise operations. Not all of these may be supported at all
569 -- sizes, and only integral MachReps are valid.
574 MO_Shl _ -> ptext (sLit "<<")
575 MO_U_Shr _ -> ptext (sLit ">>") -- unsigned shift right
576 MO_S_Shr _ -> ptext (sLit ">>") -- signed shift right
578 -- Conversions. Some of these will be NOPs, but never those that convert
579 -- between ints and floats.
580 -- Floating-point conversions use the signed variant.
581 -- We won't know to generate (void*) casts here, but maybe from
585 MO_UU_Conv from to | from == to -> empty
586 MO_UU_Conv _from to -> parens (machRep_U_CType to)
588 MO_SS_Conv from to | from == to -> empty
589 MO_SS_Conv _from to -> parens (machRep_S_CType to)
591 -- TEMPORARY: the old code didn't check this case, so let's leave it out
592 -- to facilitate comparisons against the old output code.
593 --MO_FF_Conv from to | from == to -> empty
594 MO_FF_Conv _from to -> parens (machRep_F_CType to)
596 MO_SF_Conv _from to -> parens (machRep_F_CType to)
597 MO_FS_Conv _from to -> parens (machRep_S_CType to)
599 _ -> pprTrace "offending mop" (ptext $ sLit $ show mop) $
600 panic "PprC.pprMachOp_for_C: unknown machop"
602 signedOp :: MachOp -> Bool -- Argument type(s) are signed ints
603 signedOp (MO_S_Quot _) = True
604 signedOp (MO_S_Rem _) = True
605 signedOp (MO_S_Neg _) = True
606 signedOp (MO_S_Ge _) = True
607 signedOp (MO_S_Le _) = True
608 signedOp (MO_S_Gt _) = True
609 signedOp (MO_S_Lt _) = True
610 signedOp (MO_S_Shr _) = True
611 signedOp (MO_SS_Conv _ _) = True
612 signedOp (MO_SF_Conv _ _) = True
615 floatComparison :: MachOp -> Bool -- comparison between float args
616 floatComparison (MO_F_Eq _) = True
617 floatComparison (MO_F_Ne _) = True
618 floatComparison (MO_F_Ge _) = True
619 floatComparison (MO_F_Le _) = True
620 floatComparison (MO_F_Gt _) = True
621 floatComparison (MO_F_Lt _) = True
622 floatComparison _ = False
624 -- ---------------------------------------------------------------------
625 -- tend to be implemented by foreign calls
627 pprCallishMachOp_for_C :: CallishMachOp -> SDoc
629 pprCallishMachOp_for_C mop
631 MO_F64_Pwr -> ptext (sLit "pow")
632 MO_F64_Sin -> ptext (sLit "sin")
633 MO_F64_Cos -> ptext (sLit "cos")
634 MO_F64_Tan -> ptext (sLit "tan")
635 MO_F64_Sinh -> ptext (sLit "sinh")
636 MO_F64_Cosh -> ptext (sLit "cosh")
637 MO_F64_Tanh -> ptext (sLit "tanh")
638 MO_F64_Asin -> ptext (sLit "asin")
639 MO_F64_Acos -> ptext (sLit "acos")
640 MO_F64_Atan -> ptext (sLit "atan")
641 MO_F64_Log -> ptext (sLit "log")
642 MO_F64_Exp -> ptext (sLit "exp")
643 MO_F64_Sqrt -> ptext (sLit "sqrt")
644 MO_F32_Pwr -> ptext (sLit "powf")
645 MO_F32_Sin -> ptext (sLit "sinf")
646 MO_F32_Cos -> ptext (sLit "cosf")
647 MO_F32_Tan -> ptext (sLit "tanf")
648 MO_F32_Sinh -> ptext (sLit "sinhf")
649 MO_F32_Cosh -> ptext (sLit "coshf")
650 MO_F32_Tanh -> ptext (sLit "tanhf")
651 MO_F32_Asin -> ptext (sLit "asinf")
652 MO_F32_Acos -> ptext (sLit "acosf")
653 MO_F32_Atan -> ptext (sLit "atanf")
654 MO_F32_Log -> ptext (sLit "logf")
655 MO_F32_Exp -> ptext (sLit "expf")
656 MO_F32_Sqrt -> ptext (sLit "sqrtf")
657 MO_WriteBarrier -> ptext (sLit "write_barrier")
659 -- ---------------------------------------------------------------------
663 mkJMP_, mkFN_, mkIF_ :: SDoc -> SDoc
665 mkJMP_ i = ptext (sLit "JMP_") <> parens i
666 mkFN_ i = ptext (sLit "FN_") <> parens i -- externally visible function
667 mkIF_ i = ptext (sLit "IF_") <> parens i -- locally visible
671 mkFB_ = ptext (sLit "FB_") -- function code begin
672 mkFE_ = ptext (sLit "FE_") -- function code end
674 -- from includes/Stg.h
676 mkC_,mkW_,mkP_,mkPP_,mkI_,mkA_,mkD_,mkF_,mkB_,mkL_,mkLI_,mkLW_ :: SDoc
678 mkC_ = ptext (sLit "(C_)") -- StgChar
679 mkW_ = ptext (sLit "(W_)") -- StgWord
680 mkP_ = ptext (sLit "(P_)") -- StgWord*
681 mkPP_ = ptext (sLit "(PP_)") -- P_*
682 mkI_ = ptext (sLit "(I_)") -- StgInt
683 mkA_ = ptext (sLit "(A_)") -- StgAddr
684 mkD_ = ptext (sLit "(D_)") -- const StgWord*
685 mkF_ = ptext (sLit "(F_)") -- StgFunPtr
686 mkB_ = ptext (sLit "(B_)") -- StgByteArray
687 mkL_ = ptext (sLit "(L_)") -- StgClosurePtr
689 mkLI_ = ptext (sLit "(LI_)") -- StgInt64
690 mkLW_ = ptext (sLit "(LW_)") -- StgWord64
693 -- ---------------------------------------------------------------------
697 -- Generating assignments is what we're all about, here
699 pprAssign :: CmmReg -> CmmExpr -> SDoc
701 -- dest is a reg, rhs is a reg
702 pprAssign r1 (CmmReg r2)
703 | isPtrReg r1 && isPtrReg r2
704 = hcat [ pprAsPtrReg r1, equals, pprAsPtrReg r2, semi ]
706 -- dest is a reg, rhs is a CmmRegOff
707 pprAssign r1 (CmmRegOff r2 off)
708 | isPtrReg r1 && isPtrReg r2 && (off `rem` wORD_SIZE == 0)
709 = hcat [ pprAsPtrReg r1, equals, pprAsPtrReg r2, op, int off', semi ]
711 off1 = off `shiftR` wordShift
713 (op,off') | off >= 0 = (char '+', off1)
714 | otherwise = (char '-', -off1)
716 -- dest is a reg, rhs is anything.
717 -- We can't cast the lvalue, so we have to cast the rhs if necessary. Casting
718 -- the lvalue elicits a warning from new GCC versions (3.4+).
720 | isFixedPtrReg r1 = mkAssign (mkP_ <> pprExpr1 r2)
721 | Just ty <- strangeRegType r1 = mkAssign (parens ty <> pprExpr1 r2)
722 | otherwise = mkAssign (pprExpr r2)
723 where mkAssign x = if r1 == CmmGlobal BaseReg
724 then ptext (sLit "ASSIGN_BaseReg") <> parens x <> semi
725 else pprReg r1 <> ptext (sLit " = ") <> x <> semi
727 -- ---------------------------------------------------------------------
731 | isStrangeTypeReg reg = mkW_ <> pprReg reg
732 | otherwise = pprReg reg
734 -- True if (pprReg reg) will give an expression with type StgPtr. We
735 -- need to take care with pointer arithmetic on registers with type
737 isFixedPtrReg :: CmmReg -> Bool
738 isFixedPtrReg (CmmLocal _) = False
739 isFixedPtrReg (CmmGlobal r) = isFixedPtrGlobalReg r
741 -- True if (pprAsPtrReg reg) will give an expression with type StgPtr
742 -- JD: THIS IS HORRIBLE AND SHOULD BE RENAMED, AT THE VERY LEAST.
743 -- THE GARBAGE WITH THE VNonGcPtr HELPS MATCH THE OLD CODE GENERATOR'S OUTPUT;
744 -- I'M NOT SURE IF IT SHOULD REALLY STAY THAT WAY.
745 isPtrReg :: CmmReg -> Bool
746 isPtrReg (CmmLocal _) = False
747 isPtrReg (CmmGlobal (VanillaReg n VGcPtr)) = True -- if we print via pprAsPtrReg
748 isPtrReg (CmmGlobal (VanillaReg n VNonGcPtr)) = False --if we print via pprAsPtrReg
749 isPtrReg (CmmGlobal reg) = isFixedPtrGlobalReg reg
751 -- True if this global reg has type StgPtr
752 isFixedPtrGlobalReg :: GlobalReg -> Bool
753 isFixedPtrGlobalReg Sp = True
754 isFixedPtrGlobalReg Hp = True
755 isFixedPtrGlobalReg HpLim = True
756 isFixedPtrGlobalReg SpLim = True
757 isFixedPtrGlobalReg _ = False
759 -- True if in C this register doesn't have the type given by
760 -- (machRepCType (cmmRegType reg)), so it has to be cast.
761 isStrangeTypeReg :: CmmReg -> Bool
762 isStrangeTypeReg (CmmLocal _) = False
763 isStrangeTypeReg (CmmGlobal g) = isStrangeTypeGlobal g
765 isStrangeTypeGlobal :: GlobalReg -> Bool
766 isStrangeTypeGlobal CurrentTSO = True
767 isStrangeTypeGlobal CurrentNursery = True
768 isStrangeTypeGlobal BaseReg = True
769 isStrangeTypeGlobal r = isFixedPtrGlobalReg r
771 strangeRegType :: CmmReg -> Maybe SDoc
772 strangeRegType (CmmGlobal CurrentTSO) = Just (ptext (sLit "struct StgTSO_ *"))
773 strangeRegType (CmmGlobal CurrentNursery) = Just (ptext (sLit "struct bdescr_ *"))
774 strangeRegType (CmmGlobal BaseReg) = Just (ptext (sLit "struct StgRegTable_ *"))
775 strangeRegType _ = Nothing
777 -- pprReg just prints the register name.
779 pprReg :: CmmReg -> SDoc
781 CmmLocal local -> pprLocalReg local
782 CmmGlobal global -> pprGlobalReg global
784 pprAsPtrReg :: CmmReg -> SDoc
785 pprAsPtrReg (CmmGlobal (VanillaReg n gcp))
786 = WARN( gcp /= VGcPtr, ppr n ) char 'R' <> int n <> ptext (sLit ".p")
787 pprAsPtrReg other_reg = pprReg other_reg
789 pprGlobalReg :: GlobalReg -> SDoc
790 pprGlobalReg gr = case gr of
791 VanillaReg n _ -> char 'R' <> int n <> ptext (sLit ".w")
792 -- pprGlobalReg prints a VanillaReg as a .w regardless
793 -- Example: R1.w = R1.w & (-0x8UL);
795 FloatReg n -> char 'F' <> int n
796 DoubleReg n -> char 'D' <> int n
797 LongReg n -> char 'L' <> int n
798 Sp -> ptext (sLit "Sp")
799 SpLim -> ptext (sLit "SpLim")
800 Hp -> ptext (sLit "Hp")
801 HpLim -> ptext (sLit "HpLim")
802 CurrentTSO -> ptext (sLit "CurrentTSO")
803 CurrentNursery -> ptext (sLit "CurrentNursery")
804 HpAlloc -> ptext (sLit "HpAlloc")
805 BaseReg -> ptext (sLit "BaseReg")
806 EagerBlackholeInfo -> ptext (sLit "stg_EAGER_BLACKHOLE_info")
807 GCEnter1 -> ptext (sLit "stg_gc_enter_1")
808 GCFun -> ptext (sLit "stg_gc_fun")
810 pprLocalReg :: LocalReg -> SDoc
811 pprLocalReg (LocalReg uniq _) = char '_' <> ppr uniq
813 -- -----------------------------------------------------------------------------
816 pprCall :: SDoc -> CCallConv -> HintedCmmFormals -> HintedCmmActuals -> CmmSafety
819 pprCall ppr_fn cconv results args _
820 | not (is_cish cconv)
821 = panic "pprCall: unknown calling convention"
825 #if x86_64_TARGET_ARCH
826 -- HACK around gcc optimisations.
827 -- x86_64 needs a __DISCARD__() here, to create a barrier between
828 -- putting the arguments into temporaries and passing the arguments
829 -- to the callee, because the argument expressions may refer to
830 -- machine registers that are also used for passing arguments in the
831 -- C calling convention.
832 (if (not opt_Unregisterised)
833 then ptext (sLit "__DISCARD__();")
836 ppr_assign results (ppr_fn <> parens (commafy (map pprArg args))) <> semi
838 ppr_assign [] rhs = rhs
839 ppr_assign [CmmHinted one hint] rhs
840 = pprLocalReg one <> ptext (sLit " = ")
841 <> pprUnHint hint (localRegType one) <> rhs
842 ppr_assign _other _rhs = panic "pprCall: multiple results"
844 pprArg (CmmHinted expr AddrHint)
845 = cCast (ptext (sLit "void *")) expr
846 -- see comment by machRepHintCType below
847 pprArg (CmmHinted expr SignedHint)
848 = cCast (machRep_S_CType $ typeWidth $ cmmExprType expr) expr
849 pprArg (CmmHinted expr _other)
852 pprUnHint AddrHint rep = parens (machRepCType rep)
853 pprUnHint SignedHint rep = parens (machRepCType rep)
854 pprUnHint _ _ = empty
856 pprGlobalRegName :: GlobalReg -> SDoc
857 pprGlobalRegName gr = case gr of
858 VanillaReg n _ -> char 'R' <> int n -- without the .w suffix
861 -- Currently we only have these two calling conventions, but this might
862 -- change in the future...
863 is_cish CCallConv = True
864 is_cish StdCallConv = True
866 -- ---------------------------------------------------------------------
867 -- Find and print local and external declarations for a list of
870 pprTempAndExternDecls :: [CmmBasicBlock] -> (SDoc{-temps-}, SDoc{-externs-})
871 pprTempAndExternDecls stmts
872 = (vcat (map pprTempDecl (uniqSetToList temps)),
873 vcat (map (pprExternDecl False{-ToDo-}) (keysFM lbls)))
874 where (temps, lbls) = runTE (mapM_ te_BB stmts)
876 pprDataExterns :: [CmmStatic] -> SDoc
877 pprDataExterns statics
878 = vcat (map (pprExternDecl False{-ToDo-}) (keysFM lbls))
879 where (_, lbls) = runTE (mapM_ te_Static statics)
881 pprTempDecl :: LocalReg -> SDoc
882 pprTempDecl l@(LocalReg _ rep)
883 = hcat [ machRepCType rep, space, pprLocalReg l, semi ]
885 pprExternDecl :: Bool -> CLabel -> SDoc
886 pprExternDecl in_srt lbl
887 -- do not print anything for "known external" things
888 | not (needsCDecl lbl) = empty
889 | Just sz <- foreignLabelStdcallInfo lbl = stdcall_decl sz
891 hcat [ visibility, label_type lbl,
892 lparen, pprCLabel lbl, text ");" ]
894 label_type lbl | isCFunctionLabel lbl = ptext (sLit "F_")
895 | otherwise = ptext (sLit "I_")
898 | externallyVisibleCLabel lbl = char 'E'
899 | otherwise = char 'I'
901 -- If the label we want to refer to is a stdcall function (on Windows) then
902 -- we must generate an appropriate prototype for it, so that the C compiler will
903 -- add the @n suffix to the label (#2276)
905 ptext (sLit "extern __attribute__((stdcall)) void ") <> pprCLabel lbl
906 <> parens (commafy (replicate (sz `quot` wORD_SIZE) (machRep_U_CType wordWidth)))
909 type TEState = (UniqSet LocalReg, FiniteMap CLabel ())
910 newtype TE a = TE { unTE :: TEState -> (a, TEState) }
912 instance Monad TE where
913 TE m >>= k = TE $ \s -> case m s of (a, s') -> unTE (k a) s'
914 return a = TE $ \s -> (a, s)
916 te_lbl :: CLabel -> TE ()
917 te_lbl lbl = TE $ \(temps,lbls) -> ((), (temps, addToFM lbls lbl ()))
919 te_temp :: LocalReg -> TE ()
920 te_temp r = TE $ \(temps,lbls) -> ((), (addOneToUniqSet temps r, lbls))
922 runTE :: TE () -> TEState
923 runTE (TE m) = snd (m (emptyUniqSet, emptyFM))
925 te_Static :: CmmStatic -> TE ()
926 te_Static (CmmStaticLit lit) = te_Lit lit
927 te_Static _ = return ()
929 te_BB :: CmmBasicBlock -> TE ()
930 te_BB (BasicBlock _ ss) = mapM_ te_Stmt ss
932 te_Lit :: CmmLit -> TE ()
933 te_Lit (CmmLabel l) = te_lbl l
934 te_Lit (CmmLabelOff l _) = te_lbl l
935 te_Lit (CmmLabelDiffOff l1 l2 _) = te_lbl l1
938 te_Stmt :: CmmStmt -> TE ()
939 te_Stmt (CmmAssign r e) = te_Reg r >> te_Expr e
940 te_Stmt (CmmStore l r) = te_Expr l >> te_Expr r
941 te_Stmt (CmmCall _ rs es _ _) = mapM_ (te_temp.hintlessCmm) rs >>
942 mapM_ (te_Expr.hintlessCmm) es
943 te_Stmt (CmmCondBranch e _) = te_Expr e
944 te_Stmt (CmmSwitch e _) = te_Expr e
945 te_Stmt (CmmJump e _) = te_Expr e
946 te_Stmt _ = return ()
948 te_Expr :: CmmExpr -> TE ()
949 te_Expr (CmmLit lit) = te_Lit lit
950 te_Expr (CmmLoad e _) = te_Expr e
951 te_Expr (CmmReg r) = te_Reg r
952 te_Expr (CmmMachOp _ es) = mapM_ te_Expr es
953 te_Expr (CmmRegOff r _) = te_Reg r
955 te_Reg :: CmmReg -> TE ()
956 te_Reg (CmmLocal l) = te_temp l
960 -- ---------------------------------------------------------------------
961 -- C types for MachReps
963 cCast :: SDoc -> CmmExpr -> SDoc
964 cCast ty expr = parens ty <> pprExpr1 expr
966 cLoad :: CmmExpr -> CmmType -> SDoc
967 #ifdef BEWARE_LOAD_STORE_ALIGNMENT
969 let decl = machRepCType rep <+> ptext (sLit "x") <> semi
970 struct = ptext (sLit "struct") <+> braces (decl)
971 packed_attr = ptext (sLit "__attribute__((packed))")
972 cast = parens (struct <+> packed_attr <> char '*')
973 in parens (cast <+> pprExpr1 expr) <> ptext (sLit "->x")
975 cLoad expr rep = char '*' <> parens (cCast (machRepPtrCType rep) expr)
978 isCmmWordType :: CmmType -> Bool
979 -- True of GcPtrReg/NonGcReg of native word size
980 isCmmWordType ty = not (isFloatType ty)
981 && typeWidth ty == wordWidth
983 -- This is for finding the types of foreign call arguments. For a pointer
984 -- argument, we always cast the argument to (void *), to avoid warnings from
986 machRepHintCType :: CmmType -> ForeignHint -> SDoc
987 machRepHintCType rep AddrHint = ptext (sLit "void *")
988 machRepHintCType rep SignedHint = machRep_S_CType (typeWidth rep)
989 machRepHintCType rep _other = machRepCType rep
991 machRepPtrCType :: CmmType -> SDoc
992 machRepPtrCType r | isCmmWordType r = ptext (sLit "P_")
993 | otherwise = machRepCType r <> char '*'
995 machRepCType :: CmmType -> SDoc
996 machRepCType ty | isFloatType ty = machRep_F_CType w
997 | otherwise = machRep_U_CType w
1001 machRep_F_CType :: Width -> SDoc
1002 machRep_F_CType W32 = ptext (sLit "StgFloat") -- ToDo: correct?
1003 machRep_F_CType W64 = ptext (sLit "StgDouble")
1004 machRep_F_CType _ = panic "machRep_F_CType"
1006 machRep_U_CType :: Width -> SDoc
1007 machRep_U_CType w | w == wordWidth = ptext (sLit "W_")
1008 machRep_U_CType W8 = ptext (sLit "StgWord8")
1009 machRep_U_CType W16 = ptext (sLit "StgWord16")
1010 machRep_U_CType W32 = ptext (sLit "StgWord32")
1011 machRep_U_CType W64 = ptext (sLit "StgWord64")
1012 machRep_U_CType _ = panic "machRep_U_CType"
1014 machRep_S_CType :: Width -> SDoc
1015 machRep_S_CType w | w == wordWidth = ptext (sLit "I_")
1016 machRep_S_CType W8 = ptext (sLit "StgInt8")
1017 machRep_S_CType W16 = ptext (sLit "StgInt16")
1018 machRep_S_CType W32 = ptext (sLit "StgInt32")
1019 machRep_S_CType W64 = ptext (sLit "StgInt64")
1020 machRep_S_CType _ = panic "machRep_S_CType"
1023 -- ---------------------------------------------------------------------
1024 -- print strings as valid C strings
1026 pprStringInCStyle :: [Word8] -> SDoc
1027 pprStringInCStyle s = doubleQuotes (text (concatMap charToC s))
1029 charToC :: Word8 -> String
1031 case chr (fromIntegral w) of
1035 c | c >= ' ' && c <= '~' -> [c]
1036 | otherwise -> ['\\',
1037 chr (ord '0' + ord c `div` 64),
1038 chr (ord '0' + ord c `div` 8 `mod` 8),
1039 chr (ord '0' + ord c `mod` 8)]
1041 -- ---------------------------------------------------------------------------
1042 -- Initialising static objects with floating-point numbers. We can't
1043 -- just emit the floating point number, because C will cast it to an int
1044 -- by rounding it. We want the actual bit-representation of the float.
1046 -- This is a hack to turn the floating point numbers into ints that we
1047 -- can safely initialise to static locations.
1050 | widthInBytes W64 == 2 * wORD_SIZE = True
1051 | widthInBytes W64 == wORD_SIZE = False
1052 | otherwise = panic "big_doubles"
1054 castFloatToIntArray :: STUArray s Int Float -> ST s (STUArray s Int Int)
1055 castFloatToIntArray = castSTUArray
1057 castDoubleToIntArray :: STUArray s Int Double -> ST s (STUArray s Int Int)
1058 castDoubleToIntArray = castSTUArray
1060 -- floats are always 1 word
1061 floatToWord :: Rational -> CmmLit
1064 arr <- newArray_ ((0::Int),0)
1065 writeArray arr 0 (fromRational r)
1066 arr' <- castFloatToIntArray arr
1067 i <- readArray arr' 0
1068 return (CmmInt (toInteger i) wordWidth)
1071 doubleToWords :: Rational -> [CmmLit]
1073 | big_doubles -- doubles are 2 words
1075 arr <- newArray_ ((0::Int),1)
1076 writeArray arr 0 (fromRational r)
1077 arr' <- castDoubleToIntArray arr
1078 i1 <- readArray arr' 0
1079 i2 <- readArray arr' 1
1080 return [ CmmInt (toInteger i1) wordWidth
1081 , CmmInt (toInteger i2) wordWidth
1084 | otherwise -- doubles are 1 word
1086 arr <- newArray_ ((0::Int),0)
1087 writeArray arr 0 (fromRational r)
1088 arr' <- castDoubleToIntArray arr
1089 i <- readArray arr' 0
1090 return [ CmmInt (toInteger i) wordWidth ]
1093 -- ---------------------------------------------------------------------------
1097 wordShift = widthInLog wordWidth
1099 commafy :: [SDoc] -> SDoc
1100 commafy xs = hsep $ punctuate comma xs
1102 -- Print in C hex format: 0x13fa
1103 pprHexVal :: Integer -> Width -> SDoc
1104 pprHexVal 0 _ = ptext (sLit "0x0")
1106 | w < 0 = parens (char '-' <> ptext (sLit "0x") <> go (-w) <> repsuffix rep)
1107 | otherwise = ptext (sLit "0x") <> go w <> repsuffix rep
1109 -- type suffix for literals:
1110 -- Integer literals are unsigned in Cmm/C. We explicitly cast to
1111 -- signed values for doing signed operations, but at all other
1112 -- times values are unsigned. This also helps eliminate occasional
1113 -- warnings about integer overflow from gcc.
1115 -- on 32-bit platforms, add "ULL" to 64-bit literals
1116 repsuffix W64 | wORD_SIZE == 4 = ptext (sLit "ULL")
1117 -- on 64-bit platforms with 32-bit int, add "L" to 64-bit literals
1118 repsuffix W64 | cINT_SIZE == 4 = ptext (sLit "UL")
1119 repsuffix _ = char 'U'
1124 (q,r) = w' `quotRem` 16
1125 dig | r < 10 = char (chr (fromInteger r + ord '0'))
1126 | otherwise = char (chr (fromInteger r - 10 + ord 'a'))