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 OldPprCmm () -- Instances only
61 import qualified Data.Map as Map
65 import Control.Monad.ST
67 #if x86_64_TARGET_ARCH
68 import StaticFlags ( opt_Unregisterised )
71 #if defined(alpha_TARGET_ARCH) || defined(mips_TARGET_ARCH) || defined(mipsel_TARGET_ARCH) || defined(arm_TARGET_ARCH)
72 #define BEWARE_LOAD_STORE_ALIGNMENT
75 -- --------------------------------------------------------------------------
78 pprCs :: DynFlags -> [RawCmm] -> SDoc
80 = pprCode CStyle (vcat $ map (\c -> split_marker $$ pprC c) cmms)
83 | dopt Opt_SplitObjs dflags = ptext (sLit "__STG_SPLIT_MARKER")
86 writeCs :: DynFlags -> Handle -> [RawCmm] -> IO ()
87 writeCs dflags handle cmms
88 = printForC handle (pprCs dflags cmms)
90 -- --------------------------------------------------------------------------
91 -- Now do some real work
93 -- for fun, we could call cmmToCmm over the tops...
96 pprC :: RawCmm -> SDoc
97 pprC (Cmm tops) = vcat $ intersperse blankLine $ map pprTop tops
102 pprTop :: RawCmmTop -> SDoc
103 pprTop (CmmProc info clbl (ListGraph blocks)) =
105 then pprDataExterns info $$
106 pprWordArray (entryLblToInfoLbl clbl) info
110 -- the first block doesn't get a label:
111 (BasicBlock _ stmts : rest) -> vcat [
114 (if (externallyVisibleCLabel clbl)
115 then mkFN_ else mkIF_) (pprCLabel clbl) <+> lbrace,
118 nest 8 (vcat (map pprStmt stmts)) $$
119 vcat (map pprBBlock rest),
124 (temp_decls, extern_decls) = pprTempAndExternDecls blocks
127 -- Chunks of static data.
129 -- We only handle (a) arrays of word-sized things and (b) strings.
131 pprTop (CmmData _section _ds@[CmmDataLabel lbl, CmmString str]) =
133 pprLocalness lbl, ptext (sLit "char "), pprCLabel lbl,
134 ptext (sLit "[] = "), pprStringInCStyle str, semi
137 pprTop (CmmData _section _ds@[CmmDataLabel lbl, CmmUninitialised size]) =
139 pprLocalness lbl, ptext (sLit "char "), pprCLabel lbl,
140 brackets (int size), semi
143 pprTop top@(CmmData _section (CmmDataLabel lbl : lits)) =
144 pprDataExterns lits $$
145 pprWordArray lbl lits
147 -- Floating info table for safe a foreign call.
148 pprTop top@(CmmData _section d@(_ : _))
149 | CmmDataLabel lbl : lits <- reverse d =
150 let lits' = reverse lits
151 in pprDataExterns lits' $$
152 pprWordArray lbl lits'
154 -- these shouldn't appear?
155 pprTop (CmmData _ _) = panic "PprC.pprTop: can't handle this data"
157 -- --------------------------------------------------------------------------
158 -- BasicBlocks are self-contained entities: they always end in a jump.
160 -- Like nativeGen/AsmCodeGen, we could probably reorder blocks to turn
161 -- as many jumps as possible into fall throughs.
164 pprBBlock :: CmmBasicBlock -> SDoc
165 pprBBlock (BasicBlock lbl stmts) =
167 pprTrace "pprC.pprBBlock: curious empty code block for"
168 (pprBlockId lbl) empty
170 nest 4 (pprBlockId lbl <> colon) $$
171 nest 8 (vcat (map pprStmt stmts))
173 -- --------------------------------------------------------------------------
174 -- Info tables. Just arrays of words.
175 -- See codeGen/ClosureInfo, and nativeGen/PprMach
177 pprWordArray :: CLabel -> [CmmStatic] -> SDoc
179 = hcat [ pprLocalness lbl, ptext (sLit "StgWord")
180 , space, pprCLabel lbl, ptext (sLit "[] = {") ]
181 $$ nest 8 (commafy (pprStatics ds))
185 -- has to be static, if it isn't globally visible
187 pprLocalness :: CLabel -> SDoc
188 pprLocalness lbl | not $ externallyVisibleCLabel lbl = ptext (sLit "static ")
191 -- --------------------------------------------------------------------------
195 pprStmt :: CmmStmt -> SDoc
197 pprStmt stmt = case stmt of
199 CmmComment s -> empty -- (hang (ptext (sLit "/*")) 3 (ftext s)) $$ ptext (sLit "*/")
200 -- XXX if the string contains "*/", we need to fix it
201 -- XXX we probably want to emit these comments when
202 -- some debugging option is on. They can get quite
205 CmmAssign dest src -> pprAssign dest src
208 | typeWidth rep == W64 && wordWidth /= W64
209 -> (if isFloatType rep then ptext (sLit "ASSIGN_DBL")
210 else ptext (sLit ("ASSIGN_Word64"))) <>
211 parens (mkP_ <> pprExpr1 dest <> comma <> pprExpr src) <> semi
214 -> hsep [ pprExpr (CmmLoad dest rep), equals, pprExpr src <> semi ]
216 rep = cmmExprType src
218 CmmCall (CmmCallee fn cconv) results args safety ret ->
222 cast_fn = parens (cCast (pprCFunType (char '*') cconv results args) fn)
224 real_fun_proto lbl = char ';' <>
225 pprCFunType (pprCLabel lbl) cconv results args <>
226 noreturn_attr <> semi
228 fun_proto lbl = ptext (sLit ";EF_(") <>
229 pprCLabel lbl <> char ')' <> semi
231 noreturn_attr = case ret of
232 CmmNeverReturns -> text "__attribute__ ((noreturn))"
233 CmmMayReturn -> empty
235 -- See wiki:Commentary/Compiler/Backends/PprC#Prototypes
236 (maybe_proto, fnCall) =
238 CmmLit (CmmLabel lbl)
239 | StdCallConv <- cconv ->
240 let myCall = pprCall (pprCLabel lbl) cconv results args safety
241 in (real_fun_proto lbl, myCall)
242 -- stdcall functions must be declared with
243 -- a function type, otherwise the C compiler
244 -- doesn't add the @n suffix to the label. We
245 -- can't add the @n suffix ourselves, because
247 | CmmNeverReturns <- ret ->
248 let myCall = pprCall (pprCLabel lbl) cconv results args safety
249 in (real_fun_proto lbl, myCall)
250 | not (isMathFun lbl) ->
251 let myCall = braces (
252 pprCFunType (char '*' <> text "ghcFunPtr") cconv results args <> semi
253 $$ text "ghcFunPtr" <+> equals <+> cast_fn <> semi
254 $$ pprCall (text "ghcFunPtr") cconv results args safety <> semi
256 in (fun_proto lbl, myCall)
258 (empty {- no proto -},
259 pprCall cast_fn cconv results args safety <> semi)
260 -- for a dynamic call, no declaration is necessary.
262 CmmCall (CmmPrim op) results args safety _ret ->
263 pprCall ppr_fn CCallConv results args safety
265 ppr_fn = pprCallishMachOp_for_C op
267 CmmBranch ident -> pprBranch ident
268 CmmCondBranch expr ident -> pprCondBranch expr ident
269 CmmJump lbl _params -> mkJMP_(pprExpr lbl) <> semi
270 CmmSwitch arg ids -> pprSwitch arg ids
272 pprCFunType :: SDoc -> CCallConv -> HintedCmmFormals -> HintedCmmActuals -> SDoc
273 pprCFunType ppr_fn cconv ress args
275 parens (text (ccallConvAttribute cconv) <> ppr_fn) <>
276 parens (commafy (map arg_type args))
278 res_type [] = ptext (sLit "void")
279 res_type [CmmHinted one hint] = machRepHintCType (localRegType one) hint
281 arg_type (CmmHinted expr hint) = machRepHintCType (cmmExprType expr) hint
283 -- ---------------------------------------------------------------------
284 -- unconditional branches
285 pprBranch :: BlockId -> SDoc
286 pprBranch ident = ptext (sLit "goto") <+> pprBlockId ident <> semi
289 -- ---------------------------------------------------------------------
290 -- conditional branches to local labels
291 pprCondBranch :: CmmExpr -> BlockId -> SDoc
292 pprCondBranch expr ident
293 = hsep [ ptext (sLit "if") , parens(pprExpr expr) ,
294 ptext (sLit "goto") , (pprBlockId ident) <> semi ]
297 -- ---------------------------------------------------------------------
298 -- a local table branch
300 -- we find the fall-through cases
302 -- N.B. we remove Nothing's from the list of branches, as they are
303 -- 'undefined'. However, they may be defined one day, so we better
304 -- document this behaviour.
306 pprSwitch :: CmmExpr -> [ Maybe BlockId ] -> SDoc
307 pprSwitch e maybe_ids
308 = let pairs = [ (ix, ident) | (ix,Just ident) <- zip [0..] maybe_ids ]
309 pairs2 = [ (map fst as, snd (head as)) | as <- groupBy sndEq pairs ]
311 (hang (ptext (sLit "switch") <+> parens ( pprExpr e ) <+> lbrace)
312 4 (vcat ( map caseify pairs2 )))
316 sndEq (_,x) (_,y) = x == y
319 caseify (ix:ixs, ident) = vcat (map do_fallthrough ixs) $$ final_branch ix
322 hsep [ ptext (sLit "case") , pprHexVal ix wordWidth <> colon ,
323 ptext (sLit "/* fall through */") ]
326 hsep [ ptext (sLit "case") , pprHexVal ix wordWidth <> colon ,
327 ptext (sLit "goto") , (pprBlockId ident) <> semi ]
329 -- ---------------------------------------------------------------------
333 -- C Types: the invariant is that the C expression generated by
337 -- has a type in C which is also given by
339 -- machRepCType (cmmExprType e)
341 -- (similar invariants apply to the rest of the pretty printer).
343 pprExpr :: CmmExpr -> SDoc
344 pprExpr e = case e of
345 CmmLit lit -> pprLit lit
348 CmmLoad e ty -> pprLoad e ty
349 CmmReg reg -> pprCastReg reg
350 CmmRegOff reg 0 -> pprCastReg reg
353 | i > 0 -> pprRegOff (char '+') i
354 | otherwise -> pprRegOff (char '-') (-i)
356 pprRegOff op i' = pprCastReg reg <> op <> int i'
358 CmmMachOp mop args -> pprMachOpApp mop args
361 pprLoad :: CmmExpr -> CmmType -> SDoc
363 | width == W64, wordWidth /= W64
364 = (if isFloatType ty then ptext (sLit "PK_DBL")
365 else ptext (sLit "PK_Word64"))
366 <> parens (mkP_ <> pprExpr1 e)
370 CmmReg r | isPtrReg r && width == wordWidth && not (isFloatType ty)
371 -> char '*' <> pprAsPtrReg r
373 CmmRegOff r 0 | isPtrReg r && width == wordWidth && not (isFloatType ty)
374 -> char '*' <> pprAsPtrReg r
376 CmmRegOff r off | isPtrReg r && width == wordWidth
377 , off `rem` wORD_SIZE == 0 && not (isFloatType ty)
378 -- ToDo: check that the offset is a word multiple?
379 -- (For tagging to work, I had to avoid unaligned loads. --ARY)
380 -> pprAsPtrReg r <> brackets (ppr (off `shiftR` wordShift))
386 pprExpr1 :: CmmExpr -> SDoc
387 pprExpr1 (CmmLit lit) = pprLit1 lit
388 pprExpr1 e@(CmmReg _reg) = pprExpr e
389 pprExpr1 other = parens (pprExpr other)
391 -- --------------------------------------------------------------------------
392 -- MachOp applications
394 pprMachOpApp :: MachOp -> [CmmExpr] -> SDoc
398 = ptext (sLit "mulIntMayOflo") <> parens (commafy (map pprExpr args))
399 where isMulMayOfloOp (MO_U_MulMayOflo _) = True
400 isMulMayOfloOp (MO_S_MulMayOflo _) = True
401 isMulMayOfloOp _ = False
403 pprMachOpApp mop args
404 | Just ty <- machOpNeedsCast mop
405 = ty <> parens (pprMachOpApp' mop args)
407 = pprMachOpApp' mop args
409 -- Comparisons in C have type 'int', but we want type W_ (this is what
410 -- resultRepOfMachOp says). The other C operations inherit their type
411 -- from their operands, so no casting is required.
412 machOpNeedsCast :: MachOp -> Maybe SDoc
414 | isComparisonMachOp mop = Just mkW_
415 | otherwise = Nothing
417 pprMachOpApp' mop args
420 [x,y] -> pprArg x <+> pprMachOp_for_C mop <+> pprArg y
423 [x] -> pprMachOp_for_C mop <> parens (pprArg x)
425 _ -> panic "PprC.pprMachOp : machop with wrong number of args"
428 -- Cast needed for signed integer ops
429 pprArg e | signedOp mop = cCast (machRep_S_CType (typeWidth (cmmExprType e))) e
430 | needsFCasts mop = cCast (machRep_F_CType (typeWidth (cmmExprType e))) e
431 | otherwise = pprExpr1 e
432 needsFCasts (MO_F_Eq _) = False
433 needsFCasts (MO_F_Ne _) = False
434 needsFCasts (MO_F_Neg _) = True
435 needsFCasts (MO_F_Quot _) = True
436 needsFCasts mop = floatComparison mop
438 -- --------------------------------------------------------------------------
441 pprLit :: CmmLit -> SDoc
442 pprLit lit = case lit of
443 CmmInt i rep -> pprHexVal i rep
445 CmmFloat f w -> parens (machRep_F_CType w) <> str
446 where d = fromRational f :: Double
447 str | isInfinite d && d < 0 = ptext (sLit "-INFINITY")
448 | isInfinite d = ptext (sLit "INFINITY")
449 | isNaN d = ptext (sLit "NAN")
450 | otherwise = text (show d)
451 -- these constants come from <math.h>
454 CmmBlock bid -> mkW_ <> pprCLabelAddr (infoTblLbl bid)
455 CmmHighStackMark -> panic "PprC printing high stack mark"
456 CmmLabel clbl -> mkW_ <> pprCLabelAddr clbl
457 CmmLabelOff clbl i -> mkW_ <> pprCLabelAddr clbl <> char '+' <> int i
458 CmmLabelDiffOff clbl1 clbl2 i
460 -- * the lit must occur in the info table clbl2
461 -- * clbl1 must be an SRT, a slow entry point or a large bitmap
462 -- The Mangler is expected to convert any reference to an SRT,
463 -- a slow entry point or a large bitmap
464 -- from an info table to an offset.
465 -> mkW_ <> pprCLabelAddr clbl1 <> char '+' <> int i
467 pprCLabelAddr lbl = char '&' <> pprCLabel lbl
469 pprLit1 :: CmmLit -> SDoc
470 pprLit1 lit@(CmmLabelOff _ _) = parens (pprLit lit)
471 pprLit1 lit@(CmmLabelDiffOff _ _ _) = parens (pprLit lit)
472 pprLit1 lit@(CmmFloat _ _) = parens (pprLit lit)
473 pprLit1 other = pprLit other
475 -- ---------------------------------------------------------------------------
478 pprStatics :: [CmmStatic] -> [SDoc]
480 pprStatics (CmmStaticLit (CmmFloat f W32) : rest)
481 -- floats are padded to a word, see #1852
482 | wORD_SIZE == 8, CmmStaticLit (CmmInt 0 W32) : rest' <- rest
483 = pprLit1 (floatToWord f) : pprStatics rest'
485 = pprLit1 (floatToWord f) : pprStatics rest
487 = pprPanic "pprStatics: float" (vcat (map (\(CmmStaticLit l) -> ppr (cmmLitType l)) rest))
488 pprStatics (CmmStaticLit (CmmFloat f W64) : rest)
489 = map pprLit1 (doubleToWords f) ++ pprStatics rest
490 pprStatics (CmmStaticLit (CmmInt i W64) : rest)
492 #ifdef WORDS_BIGENDIAN
493 = pprStatics (CmmStaticLit (CmmInt q W32) :
494 CmmStaticLit (CmmInt r W32) : rest)
496 = pprStatics (CmmStaticLit (CmmInt r W32) :
497 CmmStaticLit (CmmInt q W32) : rest)
499 where r = i .&. 0xffffffff
501 pprStatics (CmmStaticLit (CmmInt i w) : rest)
503 = panic "pprStatics: cannot emit a non-word-sized static literal"
504 pprStatics (CmmStaticLit lit : rest)
505 = pprLit1 lit : pprStatics rest
506 pprStatics (other : rest)
507 = pprPanic "pprWord" (pprStatic other)
509 pprStatic :: CmmStatic -> SDoc
510 pprStatic s = case s of
512 CmmStaticLit lit -> nest 4 (pprLit lit)
513 CmmAlign i -> nest 4 (ptext (sLit "/* align */") <+> int i)
514 CmmDataLabel clbl -> pprCLabel clbl <> colon
515 CmmUninitialised i -> nest 4 (mkC_ <> brackets (int i))
517 -- these should be inlined, like the old .hc
518 CmmString s' -> nest 4 (mkW_ <> parens(pprStringInCStyle s'))
521 -- ---------------------------------------------------------------------------
524 pprBlockId :: BlockId -> SDoc
525 pprBlockId b = char '_' <> ppr (getUnique b)
527 -- --------------------------------------------------------------------------
528 -- Print a MachOp in a way suitable for emitting via C.
531 pprMachOp_for_C :: MachOp -> SDoc
533 pprMachOp_for_C mop = case mop of
535 -- Integer operations
538 MO_Eq _ -> ptext (sLit "==")
539 MO_Ne _ -> ptext (sLit "!=")
542 MO_S_Quot _ -> char '/'
543 MO_S_Rem _ -> char '%'
544 MO_S_Neg _ -> char '-'
546 MO_U_Quot _ -> char '/'
547 MO_U_Rem _ -> char '%'
549 -- & Floating-point operations
550 MO_F_Add _ -> char '+'
551 MO_F_Sub _ -> char '-'
552 MO_F_Neg _ -> char '-'
553 MO_F_Mul _ -> char '*'
554 MO_F_Quot _ -> char '/'
556 -- Signed comparisons
557 MO_S_Ge _ -> ptext (sLit ">=")
558 MO_S_Le _ -> ptext (sLit "<=")
559 MO_S_Gt _ -> char '>'
560 MO_S_Lt _ -> char '<'
562 -- & Unsigned comparisons
563 MO_U_Ge _ -> ptext (sLit ">=")
564 MO_U_Le _ -> ptext (sLit "<=")
565 MO_U_Gt _ -> char '>'
566 MO_U_Lt _ -> char '<'
568 -- & Floating-point comparisons
569 MO_F_Eq _ -> ptext (sLit "==")
570 MO_F_Ne _ -> ptext (sLit "!=")
571 MO_F_Ge _ -> ptext (sLit ">=")
572 MO_F_Le _ -> ptext (sLit "<=")
573 MO_F_Gt _ -> char '>'
574 MO_F_Lt _ -> char '<'
576 -- Bitwise operations. Not all of these may be supported at all
577 -- sizes, and only integral MachReps are valid.
582 MO_Shl _ -> ptext (sLit "<<")
583 MO_U_Shr _ -> ptext (sLit ">>") -- unsigned shift right
584 MO_S_Shr _ -> ptext (sLit ">>") -- signed shift right
586 -- Conversions. Some of these will be NOPs, but never those that convert
587 -- between ints and floats.
588 -- Floating-point conversions use the signed variant.
589 -- We won't know to generate (void*) casts here, but maybe from
593 MO_UU_Conv from to | from == to -> empty
594 MO_UU_Conv _from to -> parens (machRep_U_CType to)
596 MO_SS_Conv from to | from == to -> empty
597 MO_SS_Conv _from to -> parens (machRep_S_CType to)
599 -- TEMPORARY: the old code didn't check this case, so let's leave it out
600 -- to facilitate comparisons against the old output code.
601 --MO_FF_Conv from to | from == to -> empty
602 MO_FF_Conv _from to -> parens (machRep_F_CType to)
604 MO_SF_Conv _from to -> parens (machRep_F_CType to)
605 MO_FS_Conv _from to -> parens (machRep_S_CType to)
607 _ -> pprTrace "offending mop" (ptext $ sLit $ show mop) $
608 panic "PprC.pprMachOp_for_C: unknown machop"
610 signedOp :: MachOp -> Bool -- Argument type(s) are signed ints
611 signedOp (MO_S_Quot _) = True
612 signedOp (MO_S_Rem _) = True
613 signedOp (MO_S_Neg _) = True
614 signedOp (MO_S_Ge _) = True
615 signedOp (MO_S_Le _) = True
616 signedOp (MO_S_Gt _) = True
617 signedOp (MO_S_Lt _) = True
618 signedOp (MO_S_Shr _) = True
619 signedOp (MO_SS_Conv _ _) = True
620 signedOp (MO_SF_Conv _ _) = True
623 floatComparison :: MachOp -> Bool -- comparison between float args
624 floatComparison (MO_F_Eq _) = True
625 floatComparison (MO_F_Ne _) = True
626 floatComparison (MO_F_Ge _) = True
627 floatComparison (MO_F_Le _) = True
628 floatComparison (MO_F_Gt _) = True
629 floatComparison (MO_F_Lt _) = True
630 floatComparison _ = False
632 -- ---------------------------------------------------------------------
633 -- tend to be implemented by foreign calls
635 pprCallishMachOp_for_C :: CallishMachOp -> SDoc
637 pprCallishMachOp_for_C mop
639 MO_F64_Pwr -> ptext (sLit "pow")
640 MO_F64_Sin -> ptext (sLit "sin")
641 MO_F64_Cos -> ptext (sLit "cos")
642 MO_F64_Tan -> ptext (sLit "tan")
643 MO_F64_Sinh -> ptext (sLit "sinh")
644 MO_F64_Cosh -> ptext (sLit "cosh")
645 MO_F64_Tanh -> ptext (sLit "tanh")
646 MO_F64_Asin -> ptext (sLit "asin")
647 MO_F64_Acos -> ptext (sLit "acos")
648 MO_F64_Atan -> ptext (sLit "atan")
649 MO_F64_Log -> ptext (sLit "log")
650 MO_F64_Exp -> ptext (sLit "exp")
651 MO_F64_Sqrt -> ptext (sLit "sqrt")
652 MO_F32_Pwr -> ptext (sLit "powf")
653 MO_F32_Sin -> ptext (sLit "sinf")
654 MO_F32_Cos -> ptext (sLit "cosf")
655 MO_F32_Tan -> ptext (sLit "tanf")
656 MO_F32_Sinh -> ptext (sLit "sinhf")
657 MO_F32_Cosh -> ptext (sLit "coshf")
658 MO_F32_Tanh -> ptext (sLit "tanhf")
659 MO_F32_Asin -> ptext (sLit "asinf")
660 MO_F32_Acos -> ptext (sLit "acosf")
661 MO_F32_Atan -> ptext (sLit "atanf")
662 MO_F32_Log -> ptext (sLit "logf")
663 MO_F32_Exp -> ptext (sLit "expf")
664 MO_F32_Sqrt -> ptext (sLit "sqrtf")
665 MO_WriteBarrier -> ptext (sLit "write_barrier")
667 -- ---------------------------------------------------------------------
671 mkJMP_, mkFN_, mkIF_ :: SDoc -> SDoc
673 mkJMP_ i = ptext (sLit "JMP_") <> parens i
674 mkFN_ i = ptext (sLit "FN_") <> parens i -- externally visible function
675 mkIF_ i = ptext (sLit "IF_") <> parens i -- locally visible
679 mkFB_ = ptext (sLit "FB_") -- function code begin
680 mkFE_ = ptext (sLit "FE_") -- function code end
682 -- from includes/Stg.h
684 mkC_,mkW_,mkP_ :: SDoc
686 mkC_ = ptext (sLit "(C_)") -- StgChar
687 mkW_ = ptext (sLit "(W_)") -- StgWord
688 mkP_ = ptext (sLit "(P_)") -- StgWord*
690 -- ---------------------------------------------------------------------
694 -- Generating assignments is what we're all about, here
696 pprAssign :: CmmReg -> CmmExpr -> SDoc
698 -- dest is a reg, rhs is a reg
699 pprAssign r1 (CmmReg r2)
700 | isPtrReg r1 && isPtrReg r2
701 = hcat [ pprAsPtrReg r1, equals, pprAsPtrReg r2, semi ]
703 -- dest is a reg, rhs is a CmmRegOff
704 pprAssign r1 (CmmRegOff r2 off)
705 | isPtrReg r1 && isPtrReg r2 && (off `rem` wORD_SIZE == 0)
706 = hcat [ pprAsPtrReg r1, equals, pprAsPtrReg r2, op, int off', semi ]
708 off1 = off `shiftR` wordShift
710 (op,off') | off >= 0 = (char '+', off1)
711 | otherwise = (char '-', -off1)
713 -- dest is a reg, rhs is anything.
714 -- We can't cast the lvalue, so we have to cast the rhs if necessary. Casting
715 -- the lvalue elicits a warning from new GCC versions (3.4+).
717 | isFixedPtrReg r1 = mkAssign (mkP_ <> pprExpr1 r2)
718 | Just ty <- strangeRegType r1 = mkAssign (parens ty <> pprExpr1 r2)
719 | otherwise = mkAssign (pprExpr r2)
720 where mkAssign x = if r1 == CmmGlobal BaseReg
721 then ptext (sLit "ASSIGN_BaseReg") <> parens x <> semi
722 else pprReg r1 <> ptext (sLit " = ") <> x <> semi
724 -- ---------------------------------------------------------------------
728 | isStrangeTypeReg reg = mkW_ <> pprReg reg
729 | otherwise = pprReg reg
731 -- True if (pprReg reg) will give an expression with type StgPtr. We
732 -- need to take care with pointer arithmetic on registers with type
734 isFixedPtrReg :: CmmReg -> Bool
735 isFixedPtrReg (CmmLocal _) = False
736 isFixedPtrReg (CmmGlobal r) = isFixedPtrGlobalReg r
738 -- True if (pprAsPtrReg reg) will give an expression with type StgPtr
739 -- JD: THIS IS HORRIBLE AND SHOULD BE RENAMED, AT THE VERY LEAST.
740 -- THE GARBAGE WITH THE VNonGcPtr HELPS MATCH THE OLD CODE GENERATOR'S OUTPUT;
741 -- I'M NOT SURE IF IT SHOULD REALLY STAY THAT WAY.
742 isPtrReg :: CmmReg -> Bool
743 isPtrReg (CmmLocal _) = False
744 isPtrReg (CmmGlobal (VanillaReg n VGcPtr)) = True -- if we print via pprAsPtrReg
745 isPtrReg (CmmGlobal (VanillaReg n VNonGcPtr)) = False --if we print via pprAsPtrReg
746 isPtrReg (CmmGlobal reg) = isFixedPtrGlobalReg reg
748 -- True if this global reg has type StgPtr
749 isFixedPtrGlobalReg :: GlobalReg -> Bool
750 isFixedPtrGlobalReg Sp = True
751 isFixedPtrGlobalReg Hp = True
752 isFixedPtrGlobalReg HpLim = True
753 isFixedPtrGlobalReg SpLim = True
754 isFixedPtrGlobalReg _ = False
756 -- True if in C this register doesn't have the type given by
757 -- (machRepCType (cmmRegType reg)), so it has to be cast.
758 isStrangeTypeReg :: CmmReg -> Bool
759 isStrangeTypeReg (CmmLocal _) = False
760 isStrangeTypeReg (CmmGlobal g) = isStrangeTypeGlobal g
762 isStrangeTypeGlobal :: GlobalReg -> Bool
763 isStrangeTypeGlobal CurrentTSO = True
764 isStrangeTypeGlobal CurrentNursery = True
765 isStrangeTypeGlobal BaseReg = True
766 isStrangeTypeGlobal r = isFixedPtrGlobalReg r
768 strangeRegType :: CmmReg -> Maybe SDoc
769 strangeRegType (CmmGlobal CurrentTSO) = Just (ptext (sLit "struct StgTSO_ *"))
770 strangeRegType (CmmGlobal CurrentNursery) = Just (ptext (sLit "struct bdescr_ *"))
771 strangeRegType (CmmGlobal BaseReg) = Just (ptext (sLit "struct StgRegTable_ *"))
772 strangeRegType _ = Nothing
774 -- pprReg just prints the register name.
776 pprReg :: CmmReg -> SDoc
778 CmmLocal local -> pprLocalReg local
779 CmmGlobal global -> pprGlobalReg global
781 pprAsPtrReg :: CmmReg -> SDoc
782 pprAsPtrReg (CmmGlobal (VanillaReg n gcp))
783 = WARN( gcp /= VGcPtr, ppr n ) char 'R' <> int n <> ptext (sLit ".p")
784 pprAsPtrReg other_reg = pprReg other_reg
786 pprGlobalReg :: GlobalReg -> SDoc
787 pprGlobalReg gr = case gr of
788 VanillaReg n _ -> char 'R' <> int n <> ptext (sLit ".w")
789 -- pprGlobalReg prints a VanillaReg as a .w regardless
790 -- Example: R1.w = R1.w & (-0x8UL);
792 FloatReg n -> char 'F' <> int n
793 DoubleReg n -> char 'D' <> int n
794 LongReg n -> char 'L' <> int n
795 Sp -> ptext (sLit "Sp")
796 SpLim -> ptext (sLit "SpLim")
797 Hp -> ptext (sLit "Hp")
798 HpLim -> ptext (sLit "HpLim")
799 CurrentTSO -> ptext (sLit "CurrentTSO")
800 CurrentNursery -> ptext (sLit "CurrentNursery")
801 HpAlloc -> ptext (sLit "HpAlloc")
802 BaseReg -> ptext (sLit "BaseReg")
803 EagerBlackholeInfo -> ptext (sLit "stg_EAGER_BLACKHOLE_info")
804 GCEnter1 -> ptext (sLit "stg_gc_enter_1")
805 GCFun -> ptext (sLit "stg_gc_fun")
807 pprLocalReg :: LocalReg -> SDoc
808 pprLocalReg (LocalReg uniq _) = char '_' <> ppr uniq
810 -- -----------------------------------------------------------------------------
813 pprCall :: SDoc -> CCallConv -> HintedCmmFormals -> HintedCmmActuals -> CmmSafety
816 pprCall ppr_fn cconv results args _
817 | not (is_cish cconv)
818 = panic "pprCall: unknown calling convention"
822 #if x86_64_TARGET_ARCH
823 -- HACK around gcc optimisations.
824 -- x86_64 needs a __DISCARD__() here, to create a barrier between
825 -- putting the arguments into temporaries and passing the arguments
826 -- to the callee, because the argument expressions may refer to
827 -- machine registers that are also used for passing arguments in the
828 -- C calling convention.
829 (if (not opt_Unregisterised)
830 then ptext (sLit "__DISCARD__();")
833 ppr_assign results (ppr_fn <> parens (commafy (map pprArg args))) <> semi
835 ppr_assign [] rhs = rhs
836 ppr_assign [CmmHinted one hint] rhs
837 = pprLocalReg one <> ptext (sLit " = ")
838 <> pprUnHint hint (localRegType one) <> rhs
839 ppr_assign _other _rhs = panic "pprCall: multiple results"
841 pprArg (CmmHinted expr AddrHint)
842 = cCast (ptext (sLit "void *")) expr
843 -- see comment by machRepHintCType below
844 pprArg (CmmHinted expr SignedHint)
845 = cCast (machRep_S_CType $ typeWidth $ cmmExprType expr) expr
846 pprArg (CmmHinted expr _other)
849 pprUnHint AddrHint rep = parens (machRepCType rep)
850 pprUnHint SignedHint rep = parens (machRepCType rep)
851 pprUnHint _ _ = empty
853 pprGlobalRegName :: GlobalReg -> SDoc
854 pprGlobalRegName gr = case gr of
855 VanillaReg n _ -> char 'R' <> int n -- without the .w suffix
858 -- Currently we only have these two calling conventions, but this might
859 -- change in the future...
860 is_cish CCallConv = True
861 is_cish StdCallConv = True
863 -- ---------------------------------------------------------------------
864 -- Find and print local and external declarations for a list of
867 pprTempAndExternDecls :: [CmmBasicBlock] -> (SDoc{-temps-}, SDoc{-externs-})
868 pprTempAndExternDecls stmts
869 = (vcat (map pprTempDecl (uniqSetToList temps)),
870 vcat (map (pprExternDecl False{-ToDo-}) (Map.keys lbls)))
871 where (temps, lbls) = runTE (mapM_ te_BB stmts)
873 pprDataExterns :: [CmmStatic] -> SDoc
874 pprDataExterns statics
875 = vcat (map (pprExternDecl False{-ToDo-}) (Map.keys lbls))
876 where (_, lbls) = runTE (mapM_ te_Static statics)
878 pprTempDecl :: LocalReg -> SDoc
879 pprTempDecl l@(LocalReg _ rep)
880 = hcat [ machRepCType rep, space, pprLocalReg l, semi ]
882 pprExternDecl :: Bool -> CLabel -> SDoc
883 pprExternDecl in_srt lbl
884 -- do not print anything for "known external" things
885 | not (needsCDecl lbl) = empty
886 | Just sz <- foreignLabelStdcallInfo lbl = stdcall_decl sz
888 hcat [ visibility, label_type lbl,
889 lparen, pprCLabel lbl, text ");" ]
891 label_type lbl | isCFunctionLabel lbl = ptext (sLit "F_")
892 | otherwise = ptext (sLit "I_")
895 | externallyVisibleCLabel lbl = char 'E'
896 | otherwise = char 'I'
898 -- If the label we want to refer to is a stdcall function (on Windows) then
899 -- we must generate an appropriate prototype for it, so that the C compiler will
900 -- add the @n suffix to the label (#2276)
902 ptext (sLit "extern __attribute__((stdcall)) void ") <> pprCLabel lbl
903 <> parens (commafy (replicate (sz `quot` wORD_SIZE) (machRep_U_CType wordWidth)))
906 type TEState = (UniqSet LocalReg, Map CLabel ())
907 newtype TE a = TE { unTE :: TEState -> (a, TEState) }
909 instance Monad TE where
910 TE m >>= k = TE $ \s -> case m s of (a, s') -> unTE (k a) s'
911 return a = TE $ \s -> (a, s)
913 te_lbl :: CLabel -> TE ()
914 te_lbl lbl = TE $ \(temps,lbls) -> ((), (temps, Map.insert lbl () lbls))
916 te_temp :: LocalReg -> TE ()
917 te_temp r = TE $ \(temps,lbls) -> ((), (addOneToUniqSet temps r, lbls))
919 runTE :: TE () -> TEState
920 runTE (TE m) = snd (m (emptyUniqSet, Map.empty))
922 te_Static :: CmmStatic -> TE ()
923 te_Static (CmmStaticLit lit) = te_Lit lit
924 te_Static _ = return ()
926 te_BB :: CmmBasicBlock -> TE ()
927 te_BB (BasicBlock _ ss) = mapM_ te_Stmt ss
929 te_Lit :: CmmLit -> TE ()
930 te_Lit (CmmLabel l) = te_lbl l
931 te_Lit (CmmLabelOff l _) = te_lbl l
932 te_Lit (CmmLabelDiffOff l1 l2 _) = te_lbl l1
935 te_Stmt :: CmmStmt -> TE ()
936 te_Stmt (CmmAssign r e) = te_Reg r >> te_Expr e
937 te_Stmt (CmmStore l r) = te_Expr l >> te_Expr r
938 te_Stmt (CmmCall _ rs es _ _) = mapM_ (te_temp.hintlessCmm) rs >>
939 mapM_ (te_Expr.hintlessCmm) es
940 te_Stmt (CmmCondBranch e _) = te_Expr e
941 te_Stmt (CmmSwitch e _) = te_Expr e
942 te_Stmt (CmmJump e _) = te_Expr e
943 te_Stmt _ = return ()
945 te_Expr :: CmmExpr -> TE ()
946 te_Expr (CmmLit lit) = te_Lit lit
947 te_Expr (CmmLoad e _) = te_Expr e
948 te_Expr (CmmReg r) = te_Reg r
949 te_Expr (CmmMachOp _ es) = mapM_ te_Expr es
950 te_Expr (CmmRegOff r _) = te_Reg r
952 te_Reg :: CmmReg -> TE ()
953 te_Reg (CmmLocal l) = te_temp l
957 -- ---------------------------------------------------------------------
958 -- C types for MachReps
960 cCast :: SDoc -> CmmExpr -> SDoc
961 cCast ty expr = parens ty <> pprExpr1 expr
963 cLoad :: CmmExpr -> CmmType -> SDoc
964 #ifdef BEWARE_LOAD_STORE_ALIGNMENT
966 let decl = machRepCType rep <+> ptext (sLit "x") <> semi
967 struct = ptext (sLit "struct") <+> braces (decl)
968 packed_attr = ptext (sLit "__attribute__((packed))")
969 cast = parens (struct <+> packed_attr <> char '*')
970 in parens (cast <+> pprExpr1 expr) <> ptext (sLit "->x")
972 cLoad expr rep = char '*' <> parens (cCast (machRepPtrCType rep) expr)
975 isCmmWordType :: CmmType -> Bool
976 -- True of GcPtrReg/NonGcReg of native word size
977 isCmmWordType ty = not (isFloatType ty)
978 && typeWidth ty == wordWidth
980 -- This is for finding the types of foreign call arguments. For a pointer
981 -- argument, we always cast the argument to (void *), to avoid warnings from
983 machRepHintCType :: CmmType -> ForeignHint -> SDoc
984 machRepHintCType rep AddrHint = ptext (sLit "void *")
985 machRepHintCType rep SignedHint = machRep_S_CType (typeWidth rep)
986 machRepHintCType rep _other = machRepCType rep
988 machRepPtrCType :: CmmType -> SDoc
989 machRepPtrCType r | isCmmWordType r = ptext (sLit "P_")
990 | otherwise = machRepCType r <> char '*'
992 machRepCType :: CmmType -> SDoc
993 machRepCType ty | isFloatType ty = machRep_F_CType w
994 | otherwise = machRep_U_CType w
998 machRep_F_CType :: Width -> SDoc
999 machRep_F_CType W32 = ptext (sLit "StgFloat") -- ToDo: correct?
1000 machRep_F_CType W64 = ptext (sLit "StgDouble")
1001 machRep_F_CType _ = panic "machRep_F_CType"
1003 machRep_U_CType :: Width -> SDoc
1004 machRep_U_CType w | w == wordWidth = ptext (sLit "W_")
1005 machRep_U_CType W8 = ptext (sLit "StgWord8")
1006 machRep_U_CType W16 = ptext (sLit "StgWord16")
1007 machRep_U_CType W32 = ptext (sLit "StgWord32")
1008 machRep_U_CType W64 = ptext (sLit "StgWord64")
1009 machRep_U_CType _ = panic "machRep_U_CType"
1011 machRep_S_CType :: Width -> SDoc
1012 machRep_S_CType w | w == wordWidth = ptext (sLit "I_")
1013 machRep_S_CType W8 = ptext (sLit "StgInt8")
1014 machRep_S_CType W16 = ptext (sLit "StgInt16")
1015 machRep_S_CType W32 = ptext (sLit "StgInt32")
1016 machRep_S_CType W64 = ptext (sLit "StgInt64")
1017 machRep_S_CType _ = panic "machRep_S_CType"
1020 -- ---------------------------------------------------------------------
1021 -- print strings as valid C strings
1023 pprStringInCStyle :: [Word8] -> SDoc
1024 pprStringInCStyle s = doubleQuotes (text (concatMap charToC s))
1026 -- ---------------------------------------------------------------------------
1027 -- Initialising static objects with floating-point numbers. We can't
1028 -- just emit the floating point number, because C will cast it to an int
1029 -- by rounding it. We want the actual bit-representation of the float.
1031 -- This is a hack to turn the floating point numbers into ints that we
1032 -- can safely initialise to static locations.
1035 | widthInBytes W64 == 2 * wORD_SIZE = True
1036 | widthInBytes W64 == wORD_SIZE = False
1037 | otherwise = panic "big_doubles"
1039 castFloatToIntArray :: STUArray s Int Float -> ST s (STUArray s Int Int)
1040 castFloatToIntArray = castSTUArray
1042 castDoubleToIntArray :: STUArray s Int Double -> ST s (STUArray s Int Int)
1043 castDoubleToIntArray = castSTUArray
1045 -- floats are always 1 word
1046 floatToWord :: Rational -> CmmLit
1049 arr <- newArray_ ((0::Int),0)
1050 writeArray arr 0 (fromRational r)
1051 arr' <- castFloatToIntArray arr
1052 i <- readArray arr' 0
1053 return (CmmInt (toInteger i) wordWidth)
1056 doubleToWords :: Rational -> [CmmLit]
1058 | big_doubles -- doubles are 2 words
1060 arr <- newArray_ ((0::Int),1)
1061 writeArray arr 0 (fromRational r)
1062 arr' <- castDoubleToIntArray arr
1063 i1 <- readArray arr' 0
1064 i2 <- readArray arr' 1
1065 return [ CmmInt (toInteger i1) wordWidth
1066 , CmmInt (toInteger i2) wordWidth
1069 | otherwise -- doubles are 1 word
1071 arr <- newArray_ ((0::Int),0)
1072 writeArray arr 0 (fromRational r)
1073 arr' <- castDoubleToIntArray arr
1074 i <- readArray arr' 0
1075 return [ CmmInt (toInteger i) wordWidth ]
1078 -- ---------------------------------------------------------------------------
1082 wordShift = widthInLog wordWidth
1084 commafy :: [SDoc] -> SDoc
1085 commafy xs = hsep $ punctuate comma xs
1087 -- Print in C hex format: 0x13fa
1088 pprHexVal :: Integer -> Width -> SDoc
1089 pprHexVal 0 _ = ptext (sLit "0x0")
1091 | w < 0 = parens (char '-' <> ptext (sLit "0x") <> go (-w) <> repsuffix rep)
1092 | otherwise = ptext (sLit "0x") <> go w <> repsuffix rep
1094 -- type suffix for literals:
1095 -- Integer literals are unsigned in Cmm/C. We explicitly cast to
1096 -- signed values for doing signed operations, but at all other
1097 -- times values are unsigned. This also helps eliminate occasional
1098 -- warnings about integer overflow from gcc.
1100 -- on 32-bit platforms, add "ULL" to 64-bit literals
1101 repsuffix W64 | wORD_SIZE == 4 = ptext (sLit "ULL")
1102 -- on 64-bit platforms with 32-bit int, add "L" to 64-bit literals
1103 repsuffix W64 | cINT_SIZE == 4 = ptext (sLit "UL")
1104 repsuffix _ = char 'U'
1109 (q,r) = w' `quotRem` 16
1110 dig | r < 10 = char (chr (fromInteger r + ord '0'))
1111 | otherwise = char (chr (fromInteger r - 10 + ord 'a'))