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
60 import qualified Data.Map as Map
64 import Control.Monad.ST
66 #if x86_64_TARGET_ARCH
67 import StaticFlags ( opt_Unregisterised )
70 #if defined(alpha_TARGET_ARCH) || defined(mips_TARGET_ARCH) || defined(mipsel_TARGET_ARCH) || defined(arm_TARGET_ARCH)
71 #define BEWARE_LOAD_STORE_ALIGNMENT
74 -- --------------------------------------------------------------------------
77 pprCs :: DynFlags -> [RawCmm] -> SDoc
79 = pprCode CStyle (vcat $ map (\c -> split_marker $$ pprC c) cmms)
82 | dopt Opt_SplitObjs dflags = ptext (sLit "__STG_SPLIT_MARKER")
85 writeCs :: DynFlags -> Handle -> [RawCmm] -> IO ()
86 writeCs dflags handle cmms
87 = printForC handle (pprCs dflags cmms)
89 -- --------------------------------------------------------------------------
90 -- Now do some real work
92 -- for fun, we could call cmmToCmm over the tops...
95 pprC :: RawCmm -> SDoc
96 pprC (Cmm tops) = vcat $ intersperse blankLine $ map pprTop tops
101 pprTop :: RawCmmTop -> SDoc
102 pprTop (CmmProc info clbl _params (ListGraph blocks)) =
104 then pprDataExterns info $$
105 pprWordArray (entryLblToInfoLbl clbl) info
109 -- the first block doesn't get a label:
110 (BasicBlock _ stmts : rest) -> vcat [
113 (if (externallyVisibleCLabel clbl)
114 then mkFN_ else mkIF_) (pprCLabel clbl) <+> lbrace,
117 nest 8 (vcat (map pprStmt stmts)) $$
118 vcat (map pprBBlock rest),
123 (temp_decls, extern_decls) = pprTempAndExternDecls blocks
126 -- Chunks of static data.
128 -- We only handle (a) arrays of word-sized things and (b) strings.
130 pprTop (CmmData _section _ds@[CmmDataLabel lbl, CmmString str]) =
132 pprLocalness lbl, ptext (sLit "char "), pprCLabel lbl,
133 ptext (sLit "[] = "), pprStringInCStyle str, semi
136 pprTop (CmmData _section _ds@[CmmDataLabel lbl, CmmUninitialised size]) =
138 pprLocalness lbl, ptext (sLit "char "), pprCLabel lbl,
139 brackets (int size), semi
142 pprTop top@(CmmData _section (CmmDataLabel lbl : lits)) =
143 pprDataExterns lits $$
144 pprWordArray lbl lits
146 -- Floating info table for safe a foreign call.
147 pprTop top@(CmmData _section d@(_ : _))
148 | CmmDataLabel lbl : lits <- reverse d =
149 let lits' = reverse lits
150 in pprDataExterns lits' $$
151 pprWordArray lbl lits'
153 -- these shouldn't appear?
154 pprTop (CmmData _ _) = panic "PprC.pprTop: can't handle this data"
156 -- --------------------------------------------------------------------------
157 -- BasicBlocks are self-contained entities: they always end in a jump.
159 -- Like nativeGen/AsmCodeGen, we could probably reorder blocks to turn
160 -- as many jumps as possible into fall throughs.
163 pprBBlock :: CmmBasicBlock -> SDoc
164 pprBBlock (BasicBlock lbl stmts) =
166 pprTrace "pprC.pprBBlock: curious empty code block for"
167 (pprBlockId lbl) empty
169 nest 4 (pprBlockId lbl <> colon) $$
170 nest 8 (vcat (map pprStmt stmts))
172 -- --------------------------------------------------------------------------
173 -- Info tables. Just arrays of words.
174 -- See codeGen/ClosureInfo, and nativeGen/PprMach
176 pprWordArray :: CLabel -> [CmmStatic] -> SDoc
178 = hcat [ pprLocalness lbl, ptext (sLit "StgWord")
179 , space, pprCLabel lbl, ptext (sLit "[] = {") ]
180 $$ nest 8 (commafy (pprStatics ds))
184 -- has to be static, if it isn't globally visible
186 pprLocalness :: CLabel -> SDoc
187 pprLocalness lbl | not $ externallyVisibleCLabel lbl = ptext (sLit "static ")
190 -- --------------------------------------------------------------------------
194 pprStmt :: CmmStmt -> SDoc
196 pprStmt stmt = case stmt of
198 CmmComment s -> empty -- (hang (ptext (sLit "/*")) 3 (ftext s)) $$ ptext (sLit "*/")
199 -- XXX if the string contains "*/", we need to fix it
200 -- XXX we probably want to emit these comments when
201 -- some debugging option is on. They can get quite
204 CmmAssign dest src -> pprAssign dest src
207 | typeWidth rep == W64 && wordWidth /= W64
208 -> (if isFloatType rep then ptext (sLit "ASSIGN_DBL")
209 else ptext (sLit ("ASSIGN_Word64"))) <>
210 parens (mkP_ <> pprExpr1 dest <> comma <> pprExpr src) <> semi
213 -> hsep [ pprExpr (CmmLoad dest rep), equals, pprExpr src <> semi ]
215 rep = cmmExprType src
217 CmmCall (CmmCallee fn cconv) results args safety ret ->
221 cast_fn = parens (cCast (pprCFunType (char '*') cconv results args) fn)
223 real_fun_proto lbl = char ';' <>
224 pprCFunType (pprCLabel lbl) cconv results args <>
225 noreturn_attr <> semi
227 fun_proto lbl = ptext (sLit ";EF_(") <>
228 pprCLabel lbl <> char ')' <> semi
230 noreturn_attr = case ret of
231 CmmNeverReturns -> text "__attribute__ ((noreturn))"
232 CmmMayReturn -> empty
234 -- See wiki:Commentary/Compiler/Backends/PprC#Prototypes
235 (maybe_proto, fnCall) =
237 CmmLit (CmmLabel lbl)
238 | StdCallConv <- cconv ->
239 let myCall = pprCall (pprCLabel lbl) cconv results args safety
240 in (real_fun_proto lbl, myCall)
241 -- stdcall functions must be declared with
242 -- a function type, otherwise the C compiler
243 -- doesn't add the @n suffix to the label. We
244 -- can't add the @n suffix ourselves, because
246 | CmmNeverReturns <- ret ->
247 let myCall = pprCall (pprCLabel lbl) cconv results args safety
248 in (real_fun_proto lbl, myCall)
249 | not (isMathFun lbl) ->
250 let myCall = braces (
251 pprCFunType (char '*' <> text "ghcFunPtr") cconv results args <> semi
252 $$ text "ghcFunPtr" <+> equals <+> cast_fn <> semi
253 $$ pprCall (text "ghcFunPtr") cconv results args safety <> semi
255 in (fun_proto lbl, myCall)
257 (empty {- no proto -},
258 pprCall cast_fn cconv results args safety <> semi)
259 -- for a dynamic call, no declaration is necessary.
261 CmmCall (CmmPrim op) results args safety _ret ->
262 pprCall ppr_fn CCallConv results args safety
264 ppr_fn = pprCallishMachOp_for_C op
266 CmmBranch ident -> pprBranch ident
267 CmmCondBranch expr ident -> pprCondBranch expr ident
268 CmmJump lbl _params -> mkJMP_(pprExpr lbl) <> semi
269 CmmSwitch arg ids -> pprSwitch arg ids
271 pprCFunType :: SDoc -> CCallConv -> HintedCmmFormals -> HintedCmmActuals -> SDoc
272 pprCFunType ppr_fn cconv ress args
274 parens (text (ccallConvAttribute cconv) <> ppr_fn) <>
275 parens (commafy (map arg_type args))
277 res_type [] = ptext (sLit "void")
278 res_type [CmmHinted one hint] = machRepHintCType (localRegType one) hint
280 arg_type (CmmHinted expr hint) = machRepHintCType (cmmExprType expr) hint
282 -- ---------------------------------------------------------------------
283 -- unconditional branches
284 pprBranch :: BlockId -> SDoc
285 pprBranch ident = ptext (sLit "goto") <+> pprBlockId ident <> semi
288 -- ---------------------------------------------------------------------
289 -- conditional branches to local labels
290 pprCondBranch :: CmmExpr -> BlockId -> SDoc
291 pprCondBranch expr ident
292 = hsep [ ptext (sLit "if") , parens(pprExpr expr) ,
293 ptext (sLit "goto") , (pprBlockId ident) <> semi ]
296 -- ---------------------------------------------------------------------
297 -- a local table branch
299 -- we find the fall-through cases
301 -- N.B. we remove Nothing's from the list of branches, as they are
302 -- 'undefined'. However, they may be defined one day, so we better
303 -- document this behaviour.
305 pprSwitch :: CmmExpr -> [ Maybe BlockId ] -> SDoc
306 pprSwitch e maybe_ids
307 = let pairs = [ (ix, ident) | (ix,Just ident) <- zip [0..] maybe_ids ]
308 pairs2 = [ (map fst as, snd (head as)) | as <- groupBy sndEq pairs ]
310 (hang (ptext (sLit "switch") <+> parens ( pprExpr e ) <+> lbrace)
311 4 (vcat ( map caseify pairs2 )))
315 sndEq (_,x) (_,y) = x == y
318 caseify (ix:ixs, ident) = vcat (map do_fallthrough ixs) $$ final_branch ix
321 hsep [ ptext (sLit "case") , pprHexVal ix wordWidth <> colon ,
322 ptext (sLit "/* fall through */") ]
325 hsep [ ptext (sLit "case") , pprHexVal ix wordWidth <> colon ,
326 ptext (sLit "goto") , (pprBlockId ident) <> semi ]
328 -- ---------------------------------------------------------------------
332 -- C Types: the invariant is that the C expression generated by
336 -- has a type in C which is also given by
338 -- machRepCType (cmmExprType e)
340 -- (similar invariants apply to the rest of the pretty printer).
342 pprExpr :: CmmExpr -> SDoc
343 pprExpr e = case e of
344 CmmLit lit -> pprLit lit
347 CmmLoad e ty -> pprLoad e ty
348 CmmReg reg -> pprCastReg reg
349 CmmRegOff reg 0 -> pprCastReg reg
352 | i > 0 -> pprRegOff (char '+') i
353 | otherwise -> pprRegOff (char '-') (-i)
355 pprRegOff op i' = pprCastReg reg <> op <> int i'
357 CmmMachOp mop args -> pprMachOpApp mop args
360 pprLoad :: CmmExpr -> CmmType -> SDoc
362 | width == W64, wordWidth /= W64
363 = (if isFloatType ty then ptext (sLit "PK_DBL")
364 else ptext (sLit "PK_Word64"))
365 <> parens (mkP_ <> pprExpr1 e)
369 CmmReg r | isPtrReg r && width == wordWidth && not (isFloatType ty)
370 -> char '*' <> pprAsPtrReg r
372 CmmRegOff r 0 | isPtrReg r && width == wordWidth && not (isFloatType ty)
373 -> char '*' <> pprAsPtrReg r
375 CmmRegOff r off | isPtrReg r && width == wordWidth
376 , off `rem` wORD_SIZE == 0 && not (isFloatType ty)
377 -- ToDo: check that the offset is a word multiple?
378 -- (For tagging to work, I had to avoid unaligned loads. --ARY)
379 -> pprAsPtrReg r <> brackets (ppr (off `shiftR` wordShift))
385 pprExpr1 :: CmmExpr -> SDoc
386 pprExpr1 (CmmLit lit) = pprLit1 lit
387 pprExpr1 e@(CmmReg _reg) = pprExpr e
388 pprExpr1 other = parens (pprExpr other)
390 -- --------------------------------------------------------------------------
391 -- MachOp applications
393 pprMachOpApp :: MachOp -> [CmmExpr] -> SDoc
397 = ptext (sLit "mulIntMayOflo") <> parens (commafy (map pprExpr args))
398 where isMulMayOfloOp (MO_U_MulMayOflo _) = True
399 isMulMayOfloOp (MO_S_MulMayOflo _) = True
400 isMulMayOfloOp _ = False
402 pprMachOpApp mop args
403 | Just ty <- machOpNeedsCast mop
404 = ty <> parens (pprMachOpApp' mop args)
406 = pprMachOpApp' mop args
408 -- Comparisons in C have type 'int', but we want type W_ (this is what
409 -- resultRepOfMachOp says). The other C operations inherit their type
410 -- from their operands, so no casting is required.
411 machOpNeedsCast :: MachOp -> Maybe SDoc
413 | isComparisonMachOp mop = Just mkW_
414 | otherwise = Nothing
416 pprMachOpApp' mop args
419 [x,y] -> pprArg x <+> pprMachOp_for_C mop <+> pprArg y
422 [x] -> pprMachOp_for_C mop <> parens (pprArg x)
424 _ -> panic "PprC.pprMachOp : machop with wrong number of args"
427 -- Cast needed for signed integer ops
428 pprArg e | signedOp mop = cCast (machRep_S_CType (typeWidth (cmmExprType e))) e
429 | needsFCasts mop = cCast (machRep_F_CType (typeWidth (cmmExprType e))) e
430 | otherwise = pprExpr1 e
431 needsFCasts (MO_F_Eq _) = False
432 needsFCasts (MO_F_Ne _) = False
433 needsFCasts (MO_F_Neg _) = True
434 needsFCasts (MO_F_Quot _) = True
435 needsFCasts mop = floatComparison mop
437 -- --------------------------------------------------------------------------
440 pprLit :: CmmLit -> SDoc
441 pprLit lit = case lit of
442 CmmInt i rep -> pprHexVal i rep
444 CmmFloat f w -> parens (machRep_F_CType w) <> str
445 where d = fromRational f :: Double
446 str | isInfinite d && d < 0 = ptext (sLit "-INFINITY")
447 | isInfinite d = ptext (sLit "INFINITY")
448 | isNaN d = ptext (sLit "NAN")
449 | otherwise = text (show d)
450 -- these constants come from <math.h>
453 CmmBlock bid -> mkW_ <> pprCLabelAddr (infoTblLbl bid)
454 CmmHighStackMark -> panic "PprC printing high stack mark"
455 CmmLabel clbl -> mkW_ <> pprCLabelAddr clbl
456 CmmLabelOff clbl i -> mkW_ <> pprCLabelAddr clbl <> char '+' <> int i
457 CmmLabelDiffOff clbl1 clbl2 i
459 -- * the lit must occur in the info table clbl2
460 -- * clbl1 must be an SRT, a slow entry point or a large bitmap
461 -- The Mangler is expected to convert any reference to an SRT,
462 -- a slow entry point or a large bitmap
463 -- from an info table to an offset.
464 -> mkW_ <> pprCLabelAddr clbl1 <> char '+' <> int i
466 pprCLabelAddr lbl = char '&' <> pprCLabel lbl
468 pprLit1 :: CmmLit -> SDoc
469 pprLit1 lit@(CmmLabelOff _ _) = parens (pprLit lit)
470 pprLit1 lit@(CmmLabelDiffOff _ _ _) = parens (pprLit lit)
471 pprLit1 lit@(CmmFloat _ _) = parens (pprLit lit)
472 pprLit1 other = pprLit other
474 -- ---------------------------------------------------------------------------
477 pprStatics :: [CmmStatic] -> [SDoc]
479 pprStatics (CmmStaticLit (CmmFloat f W32) : rest)
480 -- floats are padded to a word, see #1852
481 | wORD_SIZE == 8, CmmStaticLit (CmmInt 0 W32) : rest' <- rest
482 = pprLit1 (floatToWord f) : pprStatics rest'
484 = pprLit1 (floatToWord f) : pprStatics rest
486 = pprPanic "pprStatics: float" (vcat (map (\(CmmStaticLit l) -> ppr (cmmLitType l)) rest))
487 pprStatics (CmmStaticLit (CmmFloat f W64) : rest)
488 = map pprLit1 (doubleToWords f) ++ pprStatics rest
489 pprStatics (CmmStaticLit (CmmInt i W64) : rest)
491 #ifdef WORDS_BIGENDIAN
492 = pprStatics (CmmStaticLit (CmmInt q W32) :
493 CmmStaticLit (CmmInt r W32) : rest)
495 = pprStatics (CmmStaticLit (CmmInt r W32) :
496 CmmStaticLit (CmmInt q W32) : rest)
498 where r = i .&. 0xffffffff
500 pprStatics (CmmStaticLit (CmmInt i w) : rest)
502 = panic "pprStatics: cannot emit a non-word-sized static literal"
503 pprStatics (CmmStaticLit lit : rest)
504 = pprLit1 lit : pprStatics rest
505 pprStatics (other : rest)
506 = pprPanic "pprWord" (pprStatic other)
508 pprStatic :: CmmStatic -> SDoc
509 pprStatic s = case s of
511 CmmStaticLit lit -> nest 4 (pprLit lit)
512 CmmAlign i -> nest 4 (ptext (sLit "/* align */") <+> int i)
513 CmmDataLabel clbl -> pprCLabel clbl <> colon
514 CmmUninitialised i -> nest 4 (mkC_ <> brackets (int i))
516 -- these should be inlined, like the old .hc
517 CmmString s' -> nest 4 (mkW_ <> parens(pprStringInCStyle s'))
520 -- ---------------------------------------------------------------------------
523 pprBlockId :: BlockId -> SDoc
524 pprBlockId b = char '_' <> ppr (getUnique b)
526 -- --------------------------------------------------------------------------
527 -- Print a MachOp in a way suitable for emitting via C.
530 pprMachOp_for_C :: MachOp -> SDoc
532 pprMachOp_for_C mop = case mop of
534 -- Integer operations
537 MO_Eq _ -> ptext (sLit "==")
538 MO_Ne _ -> ptext (sLit "!=")
541 MO_S_Quot _ -> char '/'
542 MO_S_Rem _ -> char '%'
543 MO_S_Neg _ -> char '-'
545 MO_U_Quot _ -> char '/'
546 MO_U_Rem _ -> char '%'
548 -- & Floating-point operations
549 MO_F_Add _ -> char '+'
550 MO_F_Sub _ -> char '-'
551 MO_F_Neg _ -> char '-'
552 MO_F_Mul _ -> char '*'
553 MO_F_Quot _ -> char '/'
555 -- Signed comparisons
556 MO_S_Ge _ -> ptext (sLit ">=")
557 MO_S_Le _ -> ptext (sLit "<=")
558 MO_S_Gt _ -> char '>'
559 MO_S_Lt _ -> char '<'
561 -- & Unsigned comparisons
562 MO_U_Ge _ -> ptext (sLit ">=")
563 MO_U_Le _ -> ptext (sLit "<=")
564 MO_U_Gt _ -> char '>'
565 MO_U_Lt _ -> char '<'
567 -- & Floating-point comparisons
568 MO_F_Eq _ -> ptext (sLit "==")
569 MO_F_Ne _ -> ptext (sLit "!=")
570 MO_F_Ge _ -> ptext (sLit ">=")
571 MO_F_Le _ -> ptext (sLit "<=")
572 MO_F_Gt _ -> char '>'
573 MO_F_Lt _ -> char '<'
575 -- Bitwise operations. Not all of these may be supported at all
576 -- sizes, and only integral MachReps are valid.
581 MO_Shl _ -> ptext (sLit "<<")
582 MO_U_Shr _ -> ptext (sLit ">>") -- unsigned shift right
583 MO_S_Shr _ -> ptext (sLit ">>") -- signed shift right
585 -- Conversions. Some of these will be NOPs, but never those that convert
586 -- between ints and floats.
587 -- Floating-point conversions use the signed variant.
588 -- We won't know to generate (void*) casts here, but maybe from
592 MO_UU_Conv from to | from == to -> empty
593 MO_UU_Conv _from to -> parens (machRep_U_CType to)
595 MO_SS_Conv from to | from == to -> empty
596 MO_SS_Conv _from to -> parens (machRep_S_CType to)
598 -- TEMPORARY: the old code didn't check this case, so let's leave it out
599 -- to facilitate comparisons against the old output code.
600 --MO_FF_Conv from to | from == to -> empty
601 MO_FF_Conv _from to -> parens (machRep_F_CType to)
603 MO_SF_Conv _from to -> parens (machRep_F_CType to)
604 MO_FS_Conv _from to -> parens (machRep_S_CType to)
606 _ -> pprTrace "offending mop" (ptext $ sLit $ show mop) $
607 panic "PprC.pprMachOp_for_C: unknown machop"
609 signedOp :: MachOp -> Bool -- Argument type(s) are signed ints
610 signedOp (MO_S_Quot _) = True
611 signedOp (MO_S_Rem _) = True
612 signedOp (MO_S_Neg _) = True
613 signedOp (MO_S_Ge _) = True
614 signedOp (MO_S_Le _) = True
615 signedOp (MO_S_Gt _) = True
616 signedOp (MO_S_Lt _) = True
617 signedOp (MO_S_Shr _) = True
618 signedOp (MO_SS_Conv _ _) = True
619 signedOp (MO_SF_Conv _ _) = True
622 floatComparison :: MachOp -> Bool -- comparison between float args
623 floatComparison (MO_F_Eq _) = True
624 floatComparison (MO_F_Ne _) = True
625 floatComparison (MO_F_Ge _) = True
626 floatComparison (MO_F_Le _) = True
627 floatComparison (MO_F_Gt _) = True
628 floatComparison (MO_F_Lt _) = True
629 floatComparison _ = False
631 -- ---------------------------------------------------------------------
632 -- tend to be implemented by foreign calls
634 pprCallishMachOp_for_C :: CallishMachOp -> SDoc
636 pprCallishMachOp_for_C mop
638 MO_F64_Pwr -> ptext (sLit "pow")
639 MO_F64_Sin -> ptext (sLit "sin")
640 MO_F64_Cos -> ptext (sLit "cos")
641 MO_F64_Tan -> ptext (sLit "tan")
642 MO_F64_Sinh -> ptext (sLit "sinh")
643 MO_F64_Cosh -> ptext (sLit "cosh")
644 MO_F64_Tanh -> ptext (sLit "tanh")
645 MO_F64_Asin -> ptext (sLit "asin")
646 MO_F64_Acos -> ptext (sLit "acos")
647 MO_F64_Atan -> ptext (sLit "atan")
648 MO_F64_Log -> ptext (sLit "log")
649 MO_F64_Exp -> ptext (sLit "exp")
650 MO_F64_Sqrt -> ptext (sLit "sqrt")
651 MO_F32_Pwr -> ptext (sLit "powf")
652 MO_F32_Sin -> ptext (sLit "sinf")
653 MO_F32_Cos -> ptext (sLit "cosf")
654 MO_F32_Tan -> ptext (sLit "tanf")
655 MO_F32_Sinh -> ptext (sLit "sinhf")
656 MO_F32_Cosh -> ptext (sLit "coshf")
657 MO_F32_Tanh -> ptext (sLit "tanhf")
658 MO_F32_Asin -> ptext (sLit "asinf")
659 MO_F32_Acos -> ptext (sLit "acosf")
660 MO_F32_Atan -> ptext (sLit "atanf")
661 MO_F32_Log -> ptext (sLit "logf")
662 MO_F32_Exp -> ptext (sLit "expf")
663 MO_F32_Sqrt -> ptext (sLit "sqrtf")
664 MO_WriteBarrier -> ptext (sLit "write_barrier")
666 -- ---------------------------------------------------------------------
670 mkJMP_, mkFN_, mkIF_ :: SDoc -> SDoc
672 mkJMP_ i = ptext (sLit "JMP_") <> parens i
673 mkFN_ i = ptext (sLit "FN_") <> parens i -- externally visible function
674 mkIF_ i = ptext (sLit "IF_") <> parens i -- locally visible
678 mkFB_ = ptext (sLit "FB_") -- function code begin
679 mkFE_ = ptext (sLit "FE_") -- function code end
681 -- from includes/Stg.h
683 mkC_,mkW_,mkP_ :: SDoc
685 mkC_ = ptext (sLit "(C_)") -- StgChar
686 mkW_ = ptext (sLit "(W_)") -- StgWord
687 mkP_ = ptext (sLit "(P_)") -- StgWord*
689 -- ---------------------------------------------------------------------
693 -- Generating assignments is what we're all about, here
695 pprAssign :: CmmReg -> CmmExpr -> SDoc
697 -- dest is a reg, rhs is a reg
698 pprAssign r1 (CmmReg r2)
699 | isPtrReg r1 && isPtrReg r2
700 = hcat [ pprAsPtrReg r1, equals, pprAsPtrReg r2, semi ]
702 -- dest is a reg, rhs is a CmmRegOff
703 pprAssign r1 (CmmRegOff r2 off)
704 | isPtrReg r1 && isPtrReg r2 && (off `rem` wORD_SIZE == 0)
705 = hcat [ pprAsPtrReg r1, equals, pprAsPtrReg r2, op, int off', semi ]
707 off1 = off `shiftR` wordShift
709 (op,off') | off >= 0 = (char '+', off1)
710 | otherwise = (char '-', -off1)
712 -- dest is a reg, rhs is anything.
713 -- We can't cast the lvalue, so we have to cast the rhs if necessary. Casting
714 -- the lvalue elicits a warning from new GCC versions (3.4+).
716 | isFixedPtrReg r1 = mkAssign (mkP_ <> pprExpr1 r2)
717 | Just ty <- strangeRegType r1 = mkAssign (parens ty <> pprExpr1 r2)
718 | otherwise = mkAssign (pprExpr r2)
719 where mkAssign x = if r1 == CmmGlobal BaseReg
720 then ptext (sLit "ASSIGN_BaseReg") <> parens x <> semi
721 else pprReg r1 <> ptext (sLit " = ") <> x <> semi
723 -- ---------------------------------------------------------------------
727 | isStrangeTypeReg reg = mkW_ <> pprReg reg
728 | otherwise = pprReg reg
730 -- True if (pprReg reg) will give an expression with type StgPtr. We
731 -- need to take care with pointer arithmetic on registers with type
733 isFixedPtrReg :: CmmReg -> Bool
734 isFixedPtrReg (CmmLocal _) = False
735 isFixedPtrReg (CmmGlobal r) = isFixedPtrGlobalReg r
737 -- True if (pprAsPtrReg reg) will give an expression with type StgPtr
738 -- JD: THIS IS HORRIBLE AND SHOULD BE RENAMED, AT THE VERY LEAST.
739 -- THE GARBAGE WITH THE VNonGcPtr HELPS MATCH THE OLD CODE GENERATOR'S OUTPUT;
740 -- I'M NOT SURE IF IT SHOULD REALLY STAY THAT WAY.
741 isPtrReg :: CmmReg -> Bool
742 isPtrReg (CmmLocal _) = False
743 isPtrReg (CmmGlobal (VanillaReg n VGcPtr)) = True -- if we print via pprAsPtrReg
744 isPtrReg (CmmGlobal (VanillaReg n VNonGcPtr)) = False --if we print via pprAsPtrReg
745 isPtrReg (CmmGlobal reg) = isFixedPtrGlobalReg reg
747 -- True if this global reg has type StgPtr
748 isFixedPtrGlobalReg :: GlobalReg -> Bool
749 isFixedPtrGlobalReg Sp = True
750 isFixedPtrGlobalReg Hp = True
751 isFixedPtrGlobalReg HpLim = True
752 isFixedPtrGlobalReg SpLim = True
753 isFixedPtrGlobalReg _ = False
755 -- True if in C this register doesn't have the type given by
756 -- (machRepCType (cmmRegType reg)), so it has to be cast.
757 isStrangeTypeReg :: CmmReg -> Bool
758 isStrangeTypeReg (CmmLocal _) = False
759 isStrangeTypeReg (CmmGlobal g) = isStrangeTypeGlobal g
761 isStrangeTypeGlobal :: GlobalReg -> Bool
762 isStrangeTypeGlobal CurrentTSO = True
763 isStrangeTypeGlobal CurrentNursery = True
764 isStrangeTypeGlobal BaseReg = True
765 isStrangeTypeGlobal r = isFixedPtrGlobalReg r
767 strangeRegType :: CmmReg -> Maybe SDoc
768 strangeRegType (CmmGlobal CurrentTSO) = Just (ptext (sLit "struct StgTSO_ *"))
769 strangeRegType (CmmGlobal CurrentNursery) = Just (ptext (sLit "struct bdescr_ *"))
770 strangeRegType (CmmGlobal BaseReg) = Just (ptext (sLit "struct StgRegTable_ *"))
771 strangeRegType _ = Nothing
773 -- pprReg just prints the register name.
775 pprReg :: CmmReg -> SDoc
777 CmmLocal local -> pprLocalReg local
778 CmmGlobal global -> pprGlobalReg global
780 pprAsPtrReg :: CmmReg -> SDoc
781 pprAsPtrReg (CmmGlobal (VanillaReg n gcp))
782 = WARN( gcp /= VGcPtr, ppr n ) char 'R' <> int n <> ptext (sLit ".p")
783 pprAsPtrReg other_reg = pprReg other_reg
785 pprGlobalReg :: GlobalReg -> SDoc
786 pprGlobalReg gr = case gr of
787 VanillaReg n _ -> char 'R' <> int n <> ptext (sLit ".w")
788 -- pprGlobalReg prints a VanillaReg as a .w regardless
789 -- Example: R1.w = R1.w & (-0x8UL);
791 FloatReg n -> char 'F' <> int n
792 DoubleReg n -> char 'D' <> int n
793 LongReg n -> char 'L' <> int n
794 Sp -> ptext (sLit "Sp")
795 SpLim -> ptext (sLit "SpLim")
796 Hp -> ptext (sLit "Hp")
797 HpLim -> ptext (sLit "HpLim")
798 CurrentTSO -> ptext (sLit "CurrentTSO")
799 CurrentNursery -> ptext (sLit "CurrentNursery")
800 HpAlloc -> ptext (sLit "HpAlloc")
801 BaseReg -> ptext (sLit "BaseReg")
802 EagerBlackholeInfo -> ptext (sLit "stg_EAGER_BLACKHOLE_info")
803 GCEnter1 -> ptext (sLit "stg_gc_enter_1")
804 GCFun -> ptext (sLit "stg_gc_fun")
806 pprLocalReg :: LocalReg -> SDoc
807 pprLocalReg (LocalReg uniq _) = char '_' <> ppr uniq
809 -- -----------------------------------------------------------------------------
812 pprCall :: SDoc -> CCallConv -> HintedCmmFormals -> HintedCmmActuals -> CmmSafety
815 pprCall ppr_fn cconv results args _
816 | not (is_cish cconv)
817 = panic "pprCall: unknown calling convention"
821 #if x86_64_TARGET_ARCH
822 -- HACK around gcc optimisations.
823 -- x86_64 needs a __DISCARD__() here, to create a barrier between
824 -- putting the arguments into temporaries and passing the arguments
825 -- to the callee, because the argument expressions may refer to
826 -- machine registers that are also used for passing arguments in the
827 -- C calling convention.
828 (if (not opt_Unregisterised)
829 then ptext (sLit "__DISCARD__();")
832 ppr_assign results (ppr_fn <> parens (commafy (map pprArg args))) <> semi
834 ppr_assign [] rhs = rhs
835 ppr_assign [CmmHinted one hint] rhs
836 = pprLocalReg one <> ptext (sLit " = ")
837 <> pprUnHint hint (localRegType one) <> rhs
838 ppr_assign _other _rhs = panic "pprCall: multiple results"
840 pprArg (CmmHinted expr AddrHint)
841 = cCast (ptext (sLit "void *")) expr
842 -- see comment by machRepHintCType below
843 pprArg (CmmHinted expr SignedHint)
844 = cCast (machRep_S_CType $ typeWidth $ cmmExprType expr) expr
845 pprArg (CmmHinted expr _other)
848 pprUnHint AddrHint rep = parens (machRepCType rep)
849 pprUnHint SignedHint rep = parens (machRepCType rep)
850 pprUnHint _ _ = empty
852 pprGlobalRegName :: GlobalReg -> SDoc
853 pprGlobalRegName gr = case gr of
854 VanillaReg n _ -> char 'R' <> int n -- without the .w suffix
857 -- Currently we only have these two calling conventions, but this might
858 -- change in the future...
859 is_cish CCallConv = True
860 is_cish StdCallConv = True
862 -- ---------------------------------------------------------------------
863 -- Find and print local and external declarations for a list of
866 pprTempAndExternDecls :: [CmmBasicBlock] -> (SDoc{-temps-}, SDoc{-externs-})
867 pprTempAndExternDecls stmts
868 = (vcat (map pprTempDecl (uniqSetToList temps)),
869 vcat (map (pprExternDecl False{-ToDo-}) (Map.keys lbls)))
870 where (temps, lbls) = runTE (mapM_ te_BB stmts)
872 pprDataExterns :: [CmmStatic] -> SDoc
873 pprDataExterns statics
874 = vcat (map (pprExternDecl False{-ToDo-}) (Map.keys lbls))
875 where (_, lbls) = runTE (mapM_ te_Static statics)
877 pprTempDecl :: LocalReg -> SDoc
878 pprTempDecl l@(LocalReg _ rep)
879 = hcat [ machRepCType rep, space, pprLocalReg l, semi ]
881 pprExternDecl :: Bool -> CLabel -> SDoc
882 pprExternDecl in_srt lbl
883 -- do not print anything for "known external" things
884 | not (needsCDecl lbl) = empty
885 | Just sz <- foreignLabelStdcallInfo lbl = stdcall_decl sz
887 hcat [ visibility, label_type lbl,
888 lparen, pprCLabel lbl, text ");" ]
890 label_type lbl | isCFunctionLabel lbl = ptext (sLit "F_")
891 | otherwise = ptext (sLit "I_")
894 | externallyVisibleCLabel lbl = char 'E'
895 | otherwise = char 'I'
897 -- If the label we want to refer to is a stdcall function (on Windows) then
898 -- we must generate an appropriate prototype for it, so that the C compiler will
899 -- add the @n suffix to the label (#2276)
901 ptext (sLit "extern __attribute__((stdcall)) void ") <> pprCLabel lbl
902 <> parens (commafy (replicate (sz `quot` wORD_SIZE) (machRep_U_CType wordWidth)))
905 type TEState = (UniqSet LocalReg, Map CLabel ())
906 newtype TE a = TE { unTE :: TEState -> (a, TEState) }
908 instance Monad TE where
909 TE m >>= k = TE $ \s -> case m s of (a, s') -> unTE (k a) s'
910 return a = TE $ \s -> (a, s)
912 te_lbl :: CLabel -> TE ()
913 te_lbl lbl = TE $ \(temps,lbls) -> ((), (temps, Map.insert lbl () lbls))
915 te_temp :: LocalReg -> TE ()
916 te_temp r = TE $ \(temps,lbls) -> ((), (addOneToUniqSet temps r, lbls))
918 runTE :: TE () -> TEState
919 runTE (TE m) = snd (m (emptyUniqSet, Map.empty))
921 te_Static :: CmmStatic -> TE ()
922 te_Static (CmmStaticLit lit) = te_Lit lit
923 te_Static _ = return ()
925 te_BB :: CmmBasicBlock -> TE ()
926 te_BB (BasicBlock _ ss) = mapM_ te_Stmt ss
928 te_Lit :: CmmLit -> TE ()
929 te_Lit (CmmLabel l) = te_lbl l
930 te_Lit (CmmLabelOff l _) = te_lbl l
931 te_Lit (CmmLabelDiffOff l1 l2 _) = te_lbl l1
934 te_Stmt :: CmmStmt -> TE ()
935 te_Stmt (CmmAssign r e) = te_Reg r >> te_Expr e
936 te_Stmt (CmmStore l r) = te_Expr l >> te_Expr r
937 te_Stmt (CmmCall _ rs es _ _) = mapM_ (te_temp.hintlessCmm) rs >>
938 mapM_ (te_Expr.hintlessCmm) es
939 te_Stmt (CmmCondBranch e _) = te_Expr e
940 te_Stmt (CmmSwitch e _) = te_Expr e
941 te_Stmt (CmmJump e _) = te_Expr e
942 te_Stmt _ = return ()
944 te_Expr :: CmmExpr -> TE ()
945 te_Expr (CmmLit lit) = te_Lit lit
946 te_Expr (CmmLoad e _) = te_Expr e
947 te_Expr (CmmReg r) = te_Reg r
948 te_Expr (CmmMachOp _ es) = mapM_ te_Expr es
949 te_Expr (CmmRegOff r _) = te_Reg r
951 te_Reg :: CmmReg -> TE ()
952 te_Reg (CmmLocal l) = te_temp l
956 -- ---------------------------------------------------------------------
957 -- C types for MachReps
959 cCast :: SDoc -> CmmExpr -> SDoc
960 cCast ty expr = parens ty <> pprExpr1 expr
962 cLoad :: CmmExpr -> CmmType -> SDoc
963 #ifdef BEWARE_LOAD_STORE_ALIGNMENT
965 let decl = machRepCType rep <+> ptext (sLit "x") <> semi
966 struct = ptext (sLit "struct") <+> braces (decl)
967 packed_attr = ptext (sLit "__attribute__((packed))")
968 cast = parens (struct <+> packed_attr <> char '*')
969 in parens (cast <+> pprExpr1 expr) <> ptext (sLit "->x")
971 cLoad expr rep = char '*' <> parens (cCast (machRepPtrCType rep) expr)
974 isCmmWordType :: CmmType -> Bool
975 -- True of GcPtrReg/NonGcReg of native word size
976 isCmmWordType ty = not (isFloatType ty)
977 && typeWidth ty == wordWidth
979 -- This is for finding the types of foreign call arguments. For a pointer
980 -- argument, we always cast the argument to (void *), to avoid warnings from
982 machRepHintCType :: CmmType -> ForeignHint -> SDoc
983 machRepHintCType rep AddrHint = ptext (sLit "void *")
984 machRepHintCType rep SignedHint = machRep_S_CType (typeWidth rep)
985 machRepHintCType rep _other = machRepCType rep
987 machRepPtrCType :: CmmType -> SDoc
988 machRepPtrCType r | isCmmWordType r = ptext (sLit "P_")
989 | otherwise = machRepCType r <> char '*'
991 machRepCType :: CmmType -> SDoc
992 machRepCType ty | isFloatType ty = machRep_F_CType w
993 | otherwise = machRep_U_CType w
997 machRep_F_CType :: Width -> SDoc
998 machRep_F_CType W32 = ptext (sLit "StgFloat") -- ToDo: correct?
999 machRep_F_CType W64 = ptext (sLit "StgDouble")
1000 machRep_F_CType _ = panic "machRep_F_CType"
1002 machRep_U_CType :: Width -> SDoc
1003 machRep_U_CType w | w == wordWidth = ptext (sLit "W_")
1004 machRep_U_CType W8 = ptext (sLit "StgWord8")
1005 machRep_U_CType W16 = ptext (sLit "StgWord16")
1006 machRep_U_CType W32 = ptext (sLit "StgWord32")
1007 machRep_U_CType W64 = ptext (sLit "StgWord64")
1008 machRep_U_CType _ = panic "machRep_U_CType"
1010 machRep_S_CType :: Width -> SDoc
1011 machRep_S_CType w | w == wordWidth = ptext (sLit "I_")
1012 machRep_S_CType W8 = ptext (sLit "StgInt8")
1013 machRep_S_CType W16 = ptext (sLit "StgInt16")
1014 machRep_S_CType W32 = ptext (sLit "StgInt32")
1015 machRep_S_CType W64 = ptext (sLit "StgInt64")
1016 machRep_S_CType _ = panic "machRep_S_CType"
1019 -- ---------------------------------------------------------------------
1020 -- print strings as valid C strings
1022 pprStringInCStyle :: [Word8] -> SDoc
1023 pprStringInCStyle s = doubleQuotes (text (concatMap charToC s))
1025 charToC :: Word8 -> String
1027 case chr (fromIntegral w) of
1031 c | c >= ' ' && c <= '~' -> [c]
1032 | otherwise -> ['\\',
1033 chr (ord '0' + ord c `div` 64),
1034 chr (ord '0' + ord c `div` 8 `mod` 8),
1035 chr (ord '0' + ord c `mod` 8)]
1037 -- ---------------------------------------------------------------------------
1038 -- Initialising static objects with floating-point numbers. We can't
1039 -- just emit the floating point number, because C will cast it to an int
1040 -- by rounding it. We want the actual bit-representation of the float.
1042 -- This is a hack to turn the floating point numbers into ints that we
1043 -- can safely initialise to static locations.
1046 | widthInBytes W64 == 2 * wORD_SIZE = True
1047 | widthInBytes W64 == wORD_SIZE = False
1048 | otherwise = panic "big_doubles"
1050 castFloatToIntArray :: STUArray s Int Float -> ST s (STUArray s Int Int)
1051 castFloatToIntArray = castSTUArray
1053 castDoubleToIntArray :: STUArray s Int Double -> ST s (STUArray s Int Int)
1054 castDoubleToIntArray = castSTUArray
1056 -- floats are always 1 word
1057 floatToWord :: Rational -> CmmLit
1060 arr <- newArray_ ((0::Int),0)
1061 writeArray arr 0 (fromRational r)
1062 arr' <- castFloatToIntArray arr
1063 i <- readArray arr' 0
1064 return (CmmInt (toInteger i) wordWidth)
1067 doubleToWords :: Rational -> [CmmLit]
1069 | big_doubles -- doubles are 2 words
1071 arr <- newArray_ ((0::Int),1)
1072 writeArray arr 0 (fromRational r)
1073 arr' <- castDoubleToIntArray arr
1074 i1 <- readArray arr' 0
1075 i2 <- readArray arr' 1
1076 return [ CmmInt (toInteger i1) wordWidth
1077 , CmmInt (toInteger i2) wordWidth
1080 | otherwise -- doubles are 1 word
1082 arr <- newArray_ ((0::Int),0)
1083 writeArray arr 0 (fromRational r)
1084 arr' <- castDoubleToIntArray arr
1085 i <- readArray arr' 0
1086 return [ CmmInt (toInteger i) wordWidth ]
1089 -- ---------------------------------------------------------------------------
1093 wordShift = widthInLog wordWidth
1095 commafy :: [SDoc] -> SDoc
1096 commafy xs = hsep $ punctuate comma xs
1098 -- Print in C hex format: 0x13fa
1099 pprHexVal :: Integer -> Width -> SDoc
1100 pprHexVal 0 _ = ptext (sLit "0x0")
1102 | w < 0 = parens (char '-' <> ptext (sLit "0x") <> go (-w) <> repsuffix rep)
1103 | otherwise = ptext (sLit "0x") <> go w <> repsuffix rep
1105 -- type suffix for literals:
1106 -- Integer literals are unsigned in Cmm/C. We explicitly cast to
1107 -- signed values for doing signed operations, but at all other
1108 -- times values are unsigned. This also helps eliminate occasional
1109 -- warnings about integer overflow from gcc.
1111 -- on 32-bit platforms, add "ULL" to 64-bit literals
1112 repsuffix W64 | wORD_SIZE == 4 = ptext (sLit "ULL")
1113 -- on 64-bit platforms with 32-bit int, add "L" to 64-bit literals
1114 repsuffix W64 | cINT_SIZE == 4 = ptext (sLit "UL")
1115 repsuffix _ = char 'U'
1120 (q,r) = w' `quotRem` 16
1121 dig | r < 10 = char (chr (fromInteger r + ord '0'))
1122 | otherwise = char (chr (fromInteger r - 10 + ord 'a'))