{-# LANGUAGE CPP, GADTs #-} ----------------------------------------------------------------------------- -- -- Pretty-printing of Cmm as C, suitable for feeding gcc -- -- (c) The University of Glasgow 2004-2006 -- -- Print Cmm as real C, for -fvia-C -- -- See wiki:Commentary/Compiler/Backends/PprC -- -- This is simpler than the old PprAbsC, because Cmm is "macro-expanded" -- relative to the old AbstractC, and many oddities/decorations have -- disappeared from the data type. -- -- This code generator is only supported in unregisterised mode. -- ----------------------------------------------------------------------------- module PprC ( writeCs, pprStringInCStyle ) where #include "HsVersions.h" -- Cmm stuff import GhcPrelude import BlockId import CLabel import ForeignCall import Cmm hiding (pprBBlock) import PprCmm () import Hoopl.Block import Hoopl.Collections import Hoopl.Graph import CmmUtils import CmmSwitch -- Utils import CPrim import DynFlags import FastString import Outputable import Platform import UniqSet import UniqFM import Unique import Util -- The rest import Control.Monad.ST import Data.Bits import Data.Char import Data.List import Data.Map (Map) import Data.Word import System.IO import qualified Data.Map as Map import Control.Monad (liftM, ap) import qualified Data.Array.Unsafe as U ( castSTUArray ) import Data.Array.ST -- -------------------------------------------------------------------------- -- Top level pprCs :: [RawCmmGroup] -> SDoc pprCs cmms = pprCode CStyle (vcat $ map pprC cmms) writeCs :: DynFlags -> Handle -> [RawCmmGroup] -> IO () writeCs dflags handle cmms = printForC dflags handle (pprCs cmms) -- -------------------------------------------------------------------------- -- Now do some real work -- -- for fun, we could call cmmToCmm over the tops... -- pprC :: RawCmmGroup -> SDoc pprC tops = vcat $ intersperse blankLine $ map pprTop tops -- -- top level procs -- pprTop :: RawCmmDecl -> SDoc pprTop (CmmProc infos clbl _in_live_regs graph) = (case mapLookup (g_entry graph) infos of Nothing -> empty Just (Statics info_clbl info_dat) -> pprDataExterns info_dat $$ pprWordArray info_is_in_rodata info_clbl info_dat) $$ (vcat [ blankLine, extern_decls, (if (externallyVisibleCLabel clbl) then mkFN_ else mkIF_) (ppr clbl) <+> lbrace, nest 8 temp_decls, vcat (map pprBBlock blocks), rbrace ] ) where -- info tables are always in .rodata info_is_in_rodata = True blocks = toBlockListEntryFirst graph (temp_decls, extern_decls) = pprTempAndExternDecls blocks -- Chunks of static data. -- We only handle (a) arrays of word-sized things and (b) strings. pprTop (CmmData section (Statics lbl [CmmString str])) = pprExternDecl lbl $$ hcat [ pprLocalness lbl, pprConstness (isSecConstant section), text "char ", ppr lbl, text "[] = ", pprStringInCStyle str, semi ] pprTop (CmmData section (Statics lbl [CmmUninitialised size])) = pprExternDecl lbl $$ hcat [ pprLocalness lbl, pprConstness (isSecConstant section), text "char ", ppr lbl, brackets (int size), semi ] pprTop (CmmData section (Statics lbl lits)) = pprDataExterns lits $$ pprWordArray (isSecConstant section) lbl lits -- -------------------------------------------------------------------------- -- BasicBlocks are self-contained entities: they always end in a jump. -- -- Like nativeGen/AsmCodeGen, we could probably reorder blocks to turn -- as many jumps as possible into fall throughs. -- pprBBlock :: CmmBlock -> SDoc pprBBlock block = nest 4 (pprBlockId (entryLabel block) <> colon) $$ nest 8 (vcat (map pprStmt (blockToList nodes)) $$ pprStmt last) where (_, nodes, last) = blockSplit block -- -------------------------------------------------------------------------- -- Info tables. Just arrays of words. -- See codeGen/ClosureInfo, and nativeGen/PprMach pprWordArray :: Bool -> CLabel -> [CmmStatic] -> SDoc pprWordArray is_ro lbl ds = sdocWithDynFlags $ \dflags -> -- TODO: align closures only pprExternDecl lbl $$ hcat [ pprLocalness lbl, pprConstness is_ro, text "StgWord" , space, ppr lbl, text "[]" -- See Note [StgWord alignment] , pprAlignment (wordWidth dflags) , text "= {" ] $$ nest 8 (commafy (pprStatics dflags ds)) $$ text "};" pprAlignment :: Width -> SDoc pprAlignment words = text "__attribute__((aligned(" <> int (widthInBytes words) <> text ")))" -- Note [StgWord alignment] -- C codegen builds static closures as StgWord C arrays (pprWordArray). -- Their real C type is 'StgClosure'. Macros like UNTAG_CLOSURE assume -- pointers to 'StgClosure' are aligned at pointer size boundary: -- 4 byte boundary on 32 systems -- and 8 bytes on 64-bit systems -- see TAG_MASK and TAG_BITS definition and usage. -- -- It's a reasonable assumption also known as natural alignment. -- Although some architectures have different alignment rules. -- One of known exceptions is m68k (Trac #11395, comment:16) where: -- __alignof__(StgWord) == 2, sizeof(StgWord) == 4 -- -- Thus we explicitly increase alignment by using -- __attribute__((aligned(4))) -- declaration. -- -- has to be static, if it isn't globally visible -- pprLocalness :: CLabel -> SDoc pprLocalness lbl | not $ externallyVisibleCLabel lbl = text "static " | otherwise = empty pprConstness :: Bool -> SDoc pprConstness is_ro | is_ro = text "const " | otherwise = empty -- -------------------------------------------------------------------------- -- Statements. -- pprStmt :: CmmNode e x -> SDoc pprStmt stmt = sdocWithDynFlags $ \dflags -> case stmt of CmmEntry{} -> empty CmmComment _ -> empty -- (hang (text "/*") 3 (ftext s)) $$ ptext (sLit "*/") -- XXX if the string contains "*/", we need to fix it -- XXX we probably want to emit these comments when -- some debugging option is on. They can get quite -- large. CmmTick _ -> empty CmmUnwind{} -> empty CmmAssign dest src -> pprAssign dflags dest src CmmStore dest src | typeWidth rep == W64 && wordWidth dflags /= W64 -> (if isFloatType rep then text "ASSIGN_DBL" else ptext (sLit ("ASSIGN_Word64"))) <> parens (mkP_ <> pprExpr1 dest <> comma <> pprExpr src) <> semi | otherwise -> hsep [ pprExpr (CmmLoad dest rep), equals, pprExpr src <> semi ] where rep = cmmExprType dflags src CmmUnsafeForeignCall target@(ForeignTarget fn conv) results args -> fnCall where (res_hints, arg_hints) = foreignTargetHints target hresults = zip results res_hints hargs = zip args arg_hints ForeignConvention cconv _ _ ret = conv cast_fn = parens (cCast (pprCFunType (char '*') cconv hresults hargs) fn) -- See wiki:Commentary/Compiler/Backends/PprC#Prototypes fnCall = case fn of CmmLit (CmmLabel lbl) | StdCallConv <- cconv -> pprCall (ppr lbl) cconv hresults hargs -- stdcall functions must be declared with -- a function type, otherwise the C compiler -- doesn't add the @n suffix to the label. We -- can't add the @n suffix ourselves, because -- it isn't valid C. | CmmNeverReturns <- ret -> pprCall cast_fn cconv hresults hargs <> semi | not (isMathFun lbl) -> pprForeignCall (ppr lbl) cconv hresults hargs _ -> pprCall cast_fn cconv hresults hargs <> semi -- for a dynamic call, no declaration is necessary. CmmUnsafeForeignCall (PrimTarget MO_Touch) _results _args -> empty CmmUnsafeForeignCall (PrimTarget (MO_Prefetch_Data _)) _results _args -> empty CmmUnsafeForeignCall target@(PrimTarget op) results args -> fn_call where cconv = CCallConv fn = pprCallishMachOp_for_C op (res_hints, arg_hints) = foreignTargetHints target hresults = zip results res_hints hargs = zip args arg_hints fn_call -- The mem primops carry an extra alignment arg. -- We could maybe emit an alignment directive using this info. -- We also need to cast mem primops to prevent conflicts with GCC -- builtins (see bug #5967). | Just _align <- machOpMemcpyishAlign op = (text ";EFF_(" <> fn <> char ')' <> semi) $$ pprForeignCall fn cconv hresults hargs | otherwise = pprCall fn cconv hresults hargs CmmBranch ident -> pprBranch ident CmmCondBranch expr yes no _ -> pprCondBranch expr yes no CmmCall { cml_target = expr } -> mkJMP_ (pprExpr expr) <> semi CmmSwitch arg ids -> sdocWithDynFlags $ \dflags -> pprSwitch dflags arg ids _other -> pprPanic "PprC.pprStmt" (ppr stmt) type Hinted a = (a, ForeignHint) pprForeignCall :: SDoc -> CCallConv -> [Hinted CmmFormal] -> [Hinted CmmActual] -> SDoc pprForeignCall fn cconv results args = fn_call where fn_call = braces ( pprCFunType (char '*' <> text "ghcFunPtr") cconv results args <> semi $$ text "ghcFunPtr" <+> equals <+> cast_fn <> semi $$ pprCall (text "ghcFunPtr") cconv results args <> semi ) cast_fn = parens (parens (pprCFunType (char '*') cconv results args) <> fn) pprCFunType :: SDoc -> CCallConv -> [Hinted CmmFormal] -> [Hinted CmmActual] -> SDoc pprCFunType ppr_fn cconv ress args = sdocWithDynFlags $ \dflags -> let res_type [] = text "void" res_type [(one, hint)] = machRepHintCType (localRegType one) hint res_type _ = panic "pprCFunType: only void or 1 return value supported" arg_type (expr, hint) = machRepHintCType (cmmExprType dflags expr) hint in res_type ress <+> parens (ccallConvAttribute cconv <> ppr_fn) <> parens (commafy (map arg_type args)) -- --------------------------------------------------------------------- -- unconditional branches pprBranch :: BlockId -> SDoc pprBranch ident = text "goto" <+> pprBlockId ident <> semi -- --------------------------------------------------------------------- -- conditional branches to local labels pprCondBranch :: CmmExpr -> BlockId -> BlockId -> SDoc pprCondBranch expr yes no = hsep [ text "if" , parens(pprExpr expr) , text "goto", pprBlockId yes <> semi, text "else goto", pprBlockId no <> semi ] -- --------------------------------------------------------------------- -- a local table branch -- -- we find the fall-through cases -- pprSwitch :: DynFlags -> CmmExpr -> SwitchTargets -> SDoc pprSwitch dflags e ids = (hang (text "switch" <+> parens ( pprExpr e ) <+> lbrace) 4 (vcat ( map caseify pairs ) $$ def)) $$ rbrace where (pairs, mbdef) = switchTargetsFallThrough ids -- fall through case caseify (ix:ixs, ident) = vcat (map do_fallthrough ixs) $$ final_branch ix where do_fallthrough ix = hsep [ text "case" , pprHexVal ix (wordWidth dflags) <> colon , text "/* fall through */" ] final_branch ix = hsep [ text "case" , pprHexVal ix (wordWidth dflags) <> colon , text "goto" , (pprBlockId ident) <> semi ] caseify (_ , _ ) = panic "pprSwitch: switch with no cases!" def | Just l <- mbdef = text "default: goto" <+> pprBlockId l <> semi | otherwise = empty -- --------------------------------------------------------------------- -- Expressions. -- -- C Types: the invariant is that the C expression generated by -- -- pprExpr e -- -- has a type in C which is also given by -- -- machRepCType (cmmExprType e) -- -- (similar invariants apply to the rest of the pretty printer). pprExpr :: CmmExpr -> SDoc pprExpr e = case e of CmmLit lit -> pprLit lit CmmLoad e ty -> sdocWithDynFlags $ \dflags -> pprLoad dflags e ty CmmReg reg -> pprCastReg reg CmmRegOff reg 0 -> pprCastReg reg -- CmmRegOff is an alias of MO_Add CmmRegOff reg i -> sdocWithDynFlags $ \dflags -> pprCastReg reg <> char '+' <> pprHexVal (fromIntegral i) (wordWidth dflags) CmmMachOp mop args -> pprMachOpApp mop args CmmStackSlot _ _ -> panic "pprExpr: CmmStackSlot not supported!" pprLoad :: DynFlags -> CmmExpr -> CmmType -> SDoc pprLoad dflags e ty | width == W64, wordWidth dflags /= W64 = (if isFloatType ty then text "PK_DBL" else text "PK_Word64") <> parens (mkP_ <> pprExpr1 e) | otherwise = case e of CmmReg r | isPtrReg r && width == wordWidth dflags && not (isFloatType ty) -> char '*' <> pprAsPtrReg r CmmRegOff r 0 | isPtrReg r && width == wordWidth dflags && not (isFloatType ty) -> char '*' <> pprAsPtrReg r CmmRegOff r off | isPtrReg r && width == wordWidth dflags , off `rem` wORD_SIZE dflags == 0 && not (isFloatType ty) -- ToDo: check that the offset is a word multiple? -- (For tagging to work, I had to avoid unaligned loads. --ARY) -> pprAsPtrReg r <> brackets (ppr (off `shiftR` wordShift dflags)) _other -> cLoad e ty where width = typeWidth ty pprExpr1 :: CmmExpr -> SDoc pprExpr1 (CmmLit lit) = pprLit1 lit pprExpr1 e@(CmmReg _reg) = pprExpr e pprExpr1 other = parens (pprExpr other) -- -------------------------------------------------------------------------- -- MachOp applications pprMachOpApp :: MachOp -> [CmmExpr] -> SDoc pprMachOpApp op args | isMulMayOfloOp op = text "mulIntMayOflo" <> parens (commafy (map pprExpr args)) where isMulMayOfloOp (MO_U_MulMayOflo _) = True isMulMayOfloOp (MO_S_MulMayOflo _) = True isMulMayOfloOp _ = False pprMachOpApp mop args | Just ty <- machOpNeedsCast mop = ty <> parens (pprMachOpApp' mop args) | otherwise = pprMachOpApp' mop args -- Comparisons in C have type 'int', but we want type W_ (this is what -- resultRepOfMachOp says). The other C operations inherit their type -- from their operands, so no casting is required. machOpNeedsCast :: MachOp -> Maybe SDoc machOpNeedsCast mop | isComparisonMachOp mop = Just mkW_ | otherwise = Nothing pprMachOpApp' :: MachOp -> [CmmExpr] -> SDoc pprMachOpApp' mop args = case args of -- dyadic [x,y] -> pprArg x <+> pprMachOp_for_C mop <+> pprArg y -- unary [x] -> pprMachOp_for_C mop <> parens (pprArg x) _ -> panic "PprC.pprMachOp : machop with wrong number of args" where -- Cast needed for signed integer ops pprArg e | signedOp mop = sdocWithDynFlags $ \dflags -> cCast (machRep_S_CType (typeWidth (cmmExprType dflags e))) e | needsFCasts mop = sdocWithDynFlags $ \dflags -> cCast (machRep_F_CType (typeWidth (cmmExprType dflags e))) e | otherwise = pprExpr1 e needsFCasts (MO_F_Eq _) = False needsFCasts (MO_F_Ne _) = False needsFCasts (MO_F_Neg _) = True needsFCasts (MO_F_Quot _) = True needsFCasts mop = floatComparison mop -- -------------------------------------------------------------------------- -- Literals pprLit :: CmmLit -> SDoc pprLit lit = case lit of CmmInt i rep -> pprHexVal i rep CmmFloat f w -> parens (machRep_F_CType w) <> str where d = fromRational f :: Double str | isInfinite d && d < 0 = text "-INFINITY" | isInfinite d = text "INFINITY" | isNaN d = text "NAN" | otherwise = text (show d) -- these constants come from -- see #1861 CmmVec {} -> panic "PprC printing vector literal" CmmBlock bid -> mkW_ <> pprCLabelAddr (infoTblLbl bid) CmmHighStackMark -> panic "PprC printing high stack mark" CmmLabel clbl -> mkW_ <> pprCLabelAddr clbl CmmLabelOff clbl i -> mkW_ <> pprCLabelAddr clbl <> char '+' <> int i CmmLabelDiffOff clbl1 _ i _ -- non-word widths not supported via C -- WARNING: -- * the lit must occur in the info table clbl2 -- * clbl1 must be an SRT, a slow entry point or a large bitmap -> mkW_ <> pprCLabelAddr clbl1 <> char '+' <> int i where pprCLabelAddr lbl = char '&' <> ppr lbl pprLit1 :: CmmLit -> SDoc pprLit1 lit@(CmmLabelOff _ _) = parens (pprLit lit) pprLit1 lit@(CmmLabelDiffOff _ _ _ _) = parens (pprLit lit) pprLit1 lit@(CmmFloat _ _) = parens (pprLit lit) pprLit1 other = pprLit other -- --------------------------------------------------------------------------- -- Static data pprStatics :: DynFlags -> [CmmStatic] -> [SDoc] pprStatics _ [] = [] pprStatics dflags (CmmStaticLit (CmmFloat f W32) : rest) -- odd numbers of floats are padded to a word by mkVirtHeapOffsetsWithPadding | wORD_SIZE dflags == 8, CmmStaticLit (CmmInt 0 W32) : rest' <- rest = pprLit1 (floatToWord dflags f) : pprStatics dflags rest' -- adjacent floats aren't padded but combined into a single word | wORD_SIZE dflags == 8, CmmStaticLit (CmmFloat g W32) : rest' <- rest = pprLit1 (floatPairToWord dflags f g) : pprStatics dflags rest' | wORD_SIZE dflags == 4 = pprLit1 (floatToWord dflags f) : pprStatics dflags rest | otherwise = pprPanic "pprStatics: float" (vcat (map ppr' rest)) where ppr' (CmmStaticLit l) = sdocWithDynFlags $ \dflags -> ppr (cmmLitType dflags l) ppr' _other = text "bad static!" pprStatics dflags (CmmStaticLit (CmmFloat f W64) : rest) = map pprLit1 (doubleToWords dflags f) ++ pprStatics dflags rest pprStatics dflags (CmmStaticLit (CmmInt i W64) : rest) | wordWidth dflags == W32 = if wORDS_BIGENDIAN dflags then pprStatics dflags (CmmStaticLit (CmmInt q W32) : CmmStaticLit (CmmInt r W32) : rest) else pprStatics dflags (CmmStaticLit (CmmInt r W32) : CmmStaticLit (CmmInt q W32) : rest) where r = i .&. 0xffffffff q = i `shiftR` 32 pprStatics dflags (CmmStaticLit (CmmInt a W32) : CmmStaticLit (CmmInt b W32) : rest) | wordWidth dflags == W64 = if wORDS_BIGENDIAN dflags then pprStatics dflags (CmmStaticLit (CmmInt ((shiftL a 32) .|. b) W64) : rest) else pprStatics dflags (CmmStaticLit (CmmInt ((shiftL b 32) .|. a) W64) : rest) pprStatics dflags (CmmStaticLit (CmmInt a W16) : CmmStaticLit (CmmInt b W16) : rest) | wordWidth dflags == W32 = if wORDS_BIGENDIAN dflags then pprStatics dflags (CmmStaticLit (CmmInt ((shiftL a 16) .|. b) W32) : rest) else pprStatics dflags (CmmStaticLit (CmmInt ((shiftL b 16) .|. a) W32) : rest) pprStatics dflags (CmmStaticLit (CmmInt _ w) : _) | w /= wordWidth dflags = pprPanic "pprStatics: cannot emit a non-word-sized static literal" (ppr w) pprStatics dflags (CmmStaticLit lit : rest) = pprLit1 lit : pprStatics dflags rest pprStatics _ (other : _) = pprPanic "pprStatics: other" (pprStatic other) pprStatic :: CmmStatic -> SDoc pprStatic s = case s of CmmStaticLit lit -> nest 4 (pprLit lit) CmmUninitialised i -> nest 4 (mkC_ <> brackets (int i)) -- these should be inlined, like the old .hc CmmString s' -> nest 4 (mkW_ <> parens(pprStringInCStyle s')) -- --------------------------------------------------------------------------- -- Block Ids pprBlockId :: BlockId -> SDoc pprBlockId b = char '_' <> ppr (getUnique b) -- -------------------------------------------------------------------------- -- Print a MachOp in a way suitable for emitting via C. -- pprMachOp_for_C :: MachOp -> SDoc pprMachOp_for_C mop = case mop of -- Integer operations MO_Add _ -> char '+' MO_Sub _ -> char '-' MO_Eq _ -> text "==" MO_Ne _ -> text "!=" MO_Mul _ -> char '*' MO_S_Quot _ -> char '/' MO_S_Rem _ -> char '%' MO_S_Neg _ -> char '-' MO_U_Quot _ -> char '/' MO_U_Rem _ -> char '%' -- & Floating-point operations MO_F_Add _ -> char '+' MO_F_Sub _ -> char '-' MO_F_Neg _ -> char '-' MO_F_Mul _ -> char '*' MO_F_Quot _ -> char '/' -- Signed comparisons MO_S_Ge _ -> text ">=" MO_S_Le _ -> text "<=" MO_S_Gt _ -> char '>' MO_S_Lt _ -> char '<' -- & Unsigned comparisons MO_U_Ge _ -> text ">=" MO_U_Le _ -> text "<=" MO_U_Gt _ -> char '>' MO_U_Lt _ -> char '<' -- & Floating-point comparisons MO_F_Eq _ -> text "==" MO_F_Ne _ -> text "!=" MO_F_Ge _ -> text ">=" MO_F_Le _ -> text "<=" MO_F_Gt _ -> char '>' MO_F_Lt _ -> char '<' -- Bitwise operations. Not all of these may be supported at all -- sizes, and only integral MachReps are valid. MO_And _ -> char '&' MO_Or _ -> char '|' MO_Xor _ -> char '^' MO_Not _ -> char '~' MO_Shl _ -> text "<<" MO_U_Shr _ -> text ">>" -- unsigned shift right MO_S_Shr _ -> text ">>" -- signed shift right -- Conversions. Some of these will be NOPs, but never those that convert -- between ints and floats. -- Floating-point conversions use the signed variant. -- We won't know to generate (void*) casts here, but maybe from -- context elsewhere -- noop casts MO_UU_Conv from to | from == to -> empty MO_UU_Conv _from to -> parens (machRep_U_CType to) MO_SS_Conv from to | from == to -> empty MO_SS_Conv _from to -> parens (machRep_S_CType to) MO_XX_Conv from to | from == to -> empty MO_XX_Conv _from to -> parens (machRep_U_CType to) MO_FF_Conv from to | from == to -> empty MO_FF_Conv _from to -> parens (machRep_F_CType to) MO_SF_Conv _from to -> parens (machRep_F_CType to) MO_FS_Conv _from to -> parens (machRep_S_CType to) MO_S_MulMayOflo _ -> pprTrace "offending mop:" (text "MO_S_MulMayOflo") (panic $ "PprC.pprMachOp_for_C: MO_S_MulMayOflo" ++ " should have been handled earlier!") MO_U_MulMayOflo _ -> pprTrace "offending mop:" (text "MO_U_MulMayOflo") (panic $ "PprC.pprMachOp_for_C: MO_U_MulMayOflo" ++ " should have been handled earlier!") MO_V_Insert {} -> pprTrace "offending mop:" (text "MO_V_Insert") (panic $ "PprC.pprMachOp_for_C: MO_V_Insert" ++ " should have been handled earlier!") MO_V_Extract {} -> pprTrace "offending mop:" (text "MO_V_Extract") (panic $ "PprC.pprMachOp_for_C: MO_V_Extract" ++ " should have been handled earlier!") MO_V_Add {} -> pprTrace "offending mop:" (text "MO_V_Add") (panic $ "PprC.pprMachOp_for_C: MO_V_Add" ++ " should have been handled earlier!") MO_V_Sub {} -> pprTrace "offending mop:" (text "MO_V_Sub") (panic $ "PprC.pprMachOp_for_C: MO_V_Sub" ++ " should have been handled earlier!") MO_V_Mul {} -> pprTrace "offending mop:" (text "MO_V_Mul") (panic $ "PprC.pprMachOp_for_C: MO_V_Mul" ++ " should have been handled earlier!") MO_VS_Quot {} -> pprTrace "offending mop:" (text "MO_VS_Quot") (panic $ "PprC.pprMachOp_for_C: MO_VS_Quot" ++ " should have been handled earlier!") MO_VS_Rem {} -> pprTrace "offending mop:" (text "MO_VS_Rem") (panic $ "PprC.pprMachOp_for_C: MO_VS_Rem" ++ " should have been handled earlier!") MO_VS_Neg {} -> pprTrace "offending mop:" (text "MO_VS_Neg") (panic $ "PprC.pprMachOp_for_C: MO_VS_Neg" ++ " should have been handled earlier!") MO_VU_Quot {} -> pprTrace "offending mop:" (text "MO_VU_Quot") (panic $ "PprC.pprMachOp_for_C: MO_VU_Quot" ++ " should have been handled earlier!") MO_VU_Rem {} -> pprTrace "offending mop:" (text "MO_VU_Rem") (panic $ "PprC.pprMachOp_for_C: MO_VU_Rem" ++ " should have been handled earlier!") MO_VF_Insert {} -> pprTrace "offending mop:" (text "MO_VF_Insert") (panic $ "PprC.pprMachOp_for_C: MO_VF_Insert" ++ " should have been handled earlier!") MO_VF_Extract {} -> pprTrace "offending mop:" (text "MO_VF_Extract") (panic $ "PprC.pprMachOp_for_C: MO_VF_Extract" ++ " should have been handled earlier!") MO_VF_Add {} -> pprTrace "offending mop:" (text "MO_VF_Add") (panic $ "PprC.pprMachOp_for_C: MO_VF_Add" ++ " should have been handled earlier!") MO_VF_Sub {} -> pprTrace "offending mop:" (text "MO_VF_Sub") (panic $ "PprC.pprMachOp_for_C: MO_VF_Sub" ++ " should have been handled earlier!") MO_VF_Neg {} -> pprTrace "offending mop:" (text "MO_VF_Neg") (panic $ "PprC.pprMachOp_for_C: MO_VF_Neg" ++ " should have been handled earlier!") MO_VF_Mul {} -> pprTrace "offending mop:" (text "MO_VF_Mul") (panic $ "PprC.pprMachOp_for_C: MO_VF_Mul" ++ " should have been handled earlier!") MO_VF_Quot {} -> pprTrace "offending mop:" (text "MO_VF_Quot") (panic $ "PprC.pprMachOp_for_C: MO_VF_Quot" ++ " should have been handled earlier!") MO_AlignmentCheck {} -> panic "-falignment-santisation not supported by unregisterised backend" signedOp :: MachOp -> Bool -- Argument type(s) are signed ints signedOp (MO_S_Quot _) = True signedOp (MO_S_Rem _) = True signedOp (MO_S_Neg _) = True signedOp (MO_S_Ge _) = True signedOp (MO_S_Le _) = True signedOp (MO_S_Gt _) = True signedOp (MO_S_Lt _) = True signedOp (MO_S_Shr _) = True signedOp (MO_SS_Conv _ _) = True signedOp (MO_SF_Conv _ _) = True signedOp _ = False floatComparison :: MachOp -> Bool -- comparison between float args floatComparison (MO_F_Eq _) = True floatComparison (MO_F_Ne _) = True floatComparison (MO_F_Ge _) = True floatComparison (MO_F_Le _) = True floatComparison (MO_F_Gt _) = True floatComparison (MO_F_Lt _) = True floatComparison _ = False -- --------------------------------------------------------------------- -- tend to be implemented by foreign calls pprCallishMachOp_for_C :: CallishMachOp -> SDoc pprCallishMachOp_for_C mop = case mop of MO_F64_Pwr -> text "pow" MO_F64_Sin -> text "sin" MO_F64_Cos -> text "cos" MO_F64_Tan -> text "tan" MO_F64_Sinh -> text "sinh" MO_F64_Cosh -> text "cosh" MO_F64_Tanh -> text "tanh" MO_F64_Asin -> text "asin" MO_F64_Acos -> text "acos" MO_F64_Atanh -> text "atanh" MO_F64_Asinh -> text "asinh" MO_F64_Acosh -> text "acosh" MO_F64_Atan -> text "atan" MO_F64_Log -> text "log" MO_F64_Exp -> text "exp" MO_F64_Sqrt -> text "sqrt" MO_F64_Fabs -> text "fabs" MO_F32_Pwr -> text "powf" MO_F32_Sin -> text "sinf" MO_F32_Cos -> text "cosf" MO_F32_Tan -> text "tanf" MO_F32_Sinh -> text "sinhf" MO_F32_Cosh -> text "coshf" MO_F32_Tanh -> text "tanhf" MO_F32_Asin -> text "asinf" MO_F32_Acos -> text "acosf" MO_F32_Atan -> text "atanf" MO_F32_Asinh -> text "asinhf" MO_F32_Acosh -> text "acoshf" MO_F32_Atanh -> text "atanhf" MO_F32_Log -> text "logf" MO_F32_Exp -> text "expf" MO_F32_Sqrt -> text "sqrtf" MO_F32_Fabs -> text "fabsf" MO_ReadBarrier -> text "load_load_barrier" MO_WriteBarrier -> text "write_barrier" MO_Memcpy _ -> text "memcpy" MO_Memset _ -> text "memset" MO_Memmove _ -> text "memmove" MO_Memcmp _ -> text "memcmp" (MO_BSwap w) -> ptext (sLit $ bSwapLabel w) (MO_PopCnt w) -> ptext (sLit $ popCntLabel w) (MO_Pext w) -> ptext (sLit $ pextLabel w) (MO_Pdep w) -> ptext (sLit $ pdepLabel w) (MO_Clz w) -> ptext (sLit $ clzLabel w) (MO_Ctz w) -> ptext (sLit $ ctzLabel w) (MO_AtomicRMW w amop) -> ptext (sLit $ atomicRMWLabel w amop) (MO_Cmpxchg w) -> ptext (sLit $ cmpxchgLabel w) (MO_AtomicRead w) -> ptext (sLit $ atomicReadLabel w) (MO_AtomicWrite w) -> ptext (sLit $ atomicWriteLabel w) (MO_UF_Conv w) -> ptext (sLit $ word2FloatLabel w) MO_S_QuotRem {} -> unsupported MO_U_QuotRem {} -> unsupported MO_U_QuotRem2 {} -> unsupported MO_Add2 {} -> unsupported MO_AddWordC {} -> unsupported MO_SubWordC {} -> unsupported MO_AddIntC {} -> unsupported MO_SubIntC {} -> unsupported MO_U_Mul2 {} -> unsupported MO_Touch -> unsupported (MO_Prefetch_Data _ ) -> unsupported --- we could support prefetch via "__builtin_prefetch" --- Not adding it for now where unsupported = panic ("pprCallishMachOp_for_C: " ++ show mop ++ " not supported!") -- --------------------------------------------------------------------- -- Useful #defines -- mkJMP_, mkFN_, mkIF_ :: SDoc -> SDoc mkJMP_ i = text "JMP_" <> parens i mkFN_ i = text "FN_" <> parens i -- externally visible function mkIF_ i = text "IF_" <> parens i -- locally visible -- from includes/Stg.h -- mkC_,mkW_,mkP_ :: SDoc mkC_ = text "(C_)" -- StgChar mkW_ = text "(W_)" -- StgWord mkP_ = text "(P_)" -- StgWord* -- --------------------------------------------------------------------- -- -- Assignments -- -- Generating assignments is what we're all about, here -- pprAssign :: DynFlags -> CmmReg -> CmmExpr -> SDoc -- dest is a reg, rhs is a reg pprAssign _ r1 (CmmReg r2) | isPtrReg r1 && isPtrReg r2 = hcat [ pprAsPtrReg r1, equals, pprAsPtrReg r2, semi ] -- dest is a reg, rhs is a CmmRegOff pprAssign dflags r1 (CmmRegOff r2 off) | isPtrReg r1 && isPtrReg r2 && (off `rem` wORD_SIZE dflags == 0) = hcat [ pprAsPtrReg r1, equals, pprAsPtrReg r2, op, int off', semi ] where off1 = off `shiftR` wordShift dflags (op,off') | off >= 0 = (char '+', off1) | otherwise = (char '-', -off1) -- dest is a reg, rhs is anything. -- We can't cast the lvalue, so we have to cast the rhs if necessary. Casting -- the lvalue elicits a warning from new GCC versions (3.4+). pprAssign _ r1 r2 | isFixedPtrReg r1 = mkAssign (mkP_ <> pprExpr1 r2) | Just ty <- strangeRegType r1 = mkAssign (parens ty <> pprExpr1 r2) | otherwise = mkAssign (pprExpr r2) where mkAssign x = if r1 == CmmGlobal BaseReg then text "ASSIGN_BaseReg" <> parens x <> semi else pprReg r1 <> text " = " <> x <> semi -- --------------------------------------------------------------------- -- Registers pprCastReg :: CmmReg -> SDoc pprCastReg reg | isStrangeTypeReg reg = mkW_ <> pprReg reg | otherwise = pprReg reg -- True if (pprReg reg) will give an expression with type StgPtr. We -- need to take care with pointer arithmetic on registers with type -- StgPtr. isFixedPtrReg :: CmmReg -> Bool isFixedPtrReg (CmmLocal _) = False isFixedPtrReg (CmmGlobal r) = isFixedPtrGlobalReg r -- True if (pprAsPtrReg reg) will give an expression with type StgPtr -- JD: THIS IS HORRIBLE AND SHOULD BE RENAMED, AT THE VERY LEAST. -- THE GARBAGE WITH THE VNonGcPtr HELPS MATCH THE OLD CODE GENERATOR'S OUTPUT; -- I'M NOT SURE IF IT SHOULD REALLY STAY THAT WAY. isPtrReg :: CmmReg -> Bool isPtrReg (CmmLocal _) = False isPtrReg (CmmGlobal (VanillaReg _ VGcPtr)) = True -- if we print via pprAsPtrReg isPtrReg (CmmGlobal (VanillaReg _ VNonGcPtr)) = False -- if we print via pprAsPtrReg isPtrReg (CmmGlobal reg) = isFixedPtrGlobalReg reg -- True if this global reg has type StgPtr isFixedPtrGlobalReg :: GlobalReg -> Bool isFixedPtrGlobalReg Sp = True isFixedPtrGlobalReg Hp = True isFixedPtrGlobalReg HpLim = True isFixedPtrGlobalReg SpLim = True isFixedPtrGlobalReg _ = False -- True if in C this register doesn't have the type given by -- (machRepCType (cmmRegType reg)), so it has to be cast. isStrangeTypeReg :: CmmReg -> Bool isStrangeTypeReg (CmmLocal _) = False isStrangeTypeReg (CmmGlobal g) = isStrangeTypeGlobal g isStrangeTypeGlobal :: GlobalReg -> Bool isStrangeTypeGlobal CCCS = True isStrangeTypeGlobal CurrentTSO = True isStrangeTypeGlobal CurrentNursery = True isStrangeTypeGlobal BaseReg = True isStrangeTypeGlobal r = isFixedPtrGlobalReg r strangeRegType :: CmmReg -> Maybe SDoc strangeRegType (CmmGlobal CCCS) = Just (text "struct CostCentreStack_ *") strangeRegType (CmmGlobal CurrentTSO) = Just (text "struct StgTSO_ *") strangeRegType (CmmGlobal CurrentNursery) = Just (text "struct bdescr_ *") strangeRegType (CmmGlobal BaseReg) = Just (text "struct StgRegTable_ *") strangeRegType _ = Nothing -- pprReg just prints the register name. -- pprReg :: CmmReg -> SDoc pprReg r = case r of CmmLocal local -> pprLocalReg local CmmGlobal global -> pprGlobalReg global pprAsPtrReg :: CmmReg -> SDoc pprAsPtrReg (CmmGlobal (VanillaReg n gcp)) = WARN( gcp /= VGcPtr, ppr n ) char 'R' <> int n <> text ".p" pprAsPtrReg other_reg = pprReg other_reg pprGlobalReg :: GlobalReg -> SDoc pprGlobalReg gr = case gr of VanillaReg n _ -> char 'R' <> int n <> text ".w" -- pprGlobalReg prints a VanillaReg as a .w regardless -- Example: R1.w = R1.w & (-0x8UL); -- JMP_(*R1.p); FloatReg n -> char 'F' <> int n DoubleReg n -> char 'D' <> int n LongReg n -> char 'L' <> int n Sp -> text "Sp" SpLim -> text "SpLim" Hp -> text "Hp" HpLim -> text "HpLim" CCCS -> text "CCCS" CurrentTSO -> text "CurrentTSO" CurrentNursery -> text "CurrentNursery" HpAlloc -> text "HpAlloc" BaseReg -> text "BaseReg" EagerBlackholeInfo -> text "stg_EAGER_BLACKHOLE_info" GCEnter1 -> text "stg_gc_enter_1" GCFun -> text "stg_gc_fun" other -> panic $ "pprGlobalReg: Unsupported register: " ++ show other pprLocalReg :: LocalReg -> SDoc pprLocalReg (LocalReg uniq _) = char '_' <> ppr uniq -- ----------------------------------------------------------------------------- -- Foreign Calls pprCall :: SDoc -> CCallConv -> [Hinted CmmFormal] -> [Hinted CmmActual] -> SDoc pprCall ppr_fn cconv results args | not (is_cishCC cconv) = panic $ "pprCall: unknown calling convention" | otherwise = ppr_assign results (ppr_fn <> parens (commafy (map pprArg args))) <> semi where ppr_assign [] rhs = rhs ppr_assign [(one,hint)] rhs = pprLocalReg one <> text " = " <> pprUnHint hint (localRegType one) <> rhs ppr_assign _other _rhs = panic "pprCall: multiple results" pprArg (expr, AddrHint) = cCast (text "void *") expr -- see comment by machRepHintCType below pprArg (expr, SignedHint) = sdocWithDynFlags $ \dflags -> cCast (machRep_S_CType $ typeWidth $ cmmExprType dflags expr) expr pprArg (expr, _other) = pprExpr expr pprUnHint AddrHint rep = parens (machRepCType rep) pprUnHint SignedHint rep = parens (machRepCType rep) pprUnHint _ _ = empty -- Currently we only have these two calling conventions, but this might -- change in the future... is_cishCC :: CCallConv -> Bool is_cishCC CCallConv = True is_cishCC CApiConv = True is_cishCC StdCallConv = True is_cishCC PrimCallConv = False is_cishCC JavaScriptCallConv = False -- --------------------------------------------------------------------- -- Find and print local and external declarations for a list of -- Cmm statements. -- pprTempAndExternDecls :: [CmmBlock] -> (SDoc{-temps-}, SDoc{-externs-}) pprTempAndExternDecls stmts = (pprUFM (getUniqSet temps) (vcat . map pprTempDecl), vcat (map pprExternDecl (Map.keys lbls))) where (temps, lbls) = runTE (mapM_ te_BB stmts) pprDataExterns :: [CmmStatic] -> SDoc pprDataExterns statics = vcat (map pprExternDecl (Map.keys lbls)) where (_, lbls) = runTE (mapM_ te_Static statics) pprTempDecl :: LocalReg -> SDoc pprTempDecl l@(LocalReg _ rep) = hcat [ machRepCType rep, space, pprLocalReg l, semi ] pprExternDecl :: CLabel -> SDoc pprExternDecl lbl -- do not print anything for "known external" things | not (needsCDecl lbl) = empty | Just sz <- foreignLabelStdcallInfo lbl = stdcall_decl sz | otherwise = hcat [ visibility, label_type lbl , lparen, ppr lbl, text ");" -- occasionally useful to see label type -- , text "/* ", pprDebugCLabel lbl, text " */" ] where label_type lbl | isBytesLabel lbl = text "B_" | isForeignLabel lbl && isCFunctionLabel lbl = text "FF_" | isCFunctionLabel lbl = text "F_" | isStaticClosureLabel lbl = text "C_" -- generic .rodata labels | isSomeRODataLabel lbl = text "RO_" -- generic .data labels (common case) | otherwise = text "RW_" visibility | externallyVisibleCLabel lbl = char 'E' | otherwise = char 'I' -- If the label we want to refer to is a stdcall function (on Windows) then -- we must generate an appropriate prototype for it, so that the C compiler will -- add the @n suffix to the label (#2276) stdcall_decl sz = sdocWithDynFlags $ \dflags -> text "extern __attribute__((stdcall)) void " <> ppr lbl <> parens (commafy (replicate (sz `quot` wORD_SIZE dflags) (machRep_U_CType (wordWidth dflags)))) <> semi type TEState = (UniqSet LocalReg, Map CLabel ()) newtype TE a = TE { unTE :: TEState -> (a, TEState) } instance Functor TE where fmap = liftM instance Applicative TE where pure a = TE $ \s -> (a, s) (<*>) = ap instance Monad TE where TE m >>= k = TE $ \s -> case m s of (a, s') -> unTE (k a) s' te_lbl :: CLabel -> TE () te_lbl lbl = TE $ \(temps,lbls) -> ((), (temps, Map.insert lbl () lbls)) te_temp :: LocalReg -> TE () te_temp r = TE $ \(temps,lbls) -> ((), (addOneToUniqSet temps r, lbls)) runTE :: TE () -> TEState runTE (TE m) = snd (m (emptyUniqSet, Map.empty)) te_Static :: CmmStatic -> TE () te_Static (CmmStaticLit lit) = te_Lit lit te_Static _ = return () te_BB :: CmmBlock -> TE () te_BB block = mapM_ te_Stmt (blockToList mid) >> te_Stmt last where (_, mid, last) = blockSplit block te_Lit :: CmmLit -> TE () te_Lit (CmmLabel l) = te_lbl l te_Lit (CmmLabelOff l _) = te_lbl l te_Lit (CmmLabelDiffOff l1 _ _ _) = te_lbl l1 te_Lit _ = return () te_Stmt :: CmmNode e x -> TE () te_Stmt (CmmAssign r e) = te_Reg r >> te_Expr e te_Stmt (CmmStore l r) = te_Expr l >> te_Expr r te_Stmt (CmmUnsafeForeignCall target rs es) = do te_Target target mapM_ te_temp rs mapM_ te_Expr es te_Stmt (CmmCondBranch e _ _ _) = te_Expr e te_Stmt (CmmSwitch e _) = te_Expr e te_Stmt (CmmCall { cml_target = e }) = te_Expr e te_Stmt _ = return () te_Target :: ForeignTarget -> TE () te_Target (ForeignTarget e _) = te_Expr e te_Target (PrimTarget{}) = return () te_Expr :: CmmExpr -> TE () te_Expr (CmmLit lit) = te_Lit lit te_Expr (CmmLoad e _) = te_Expr e te_Expr (CmmReg r) = te_Reg r te_Expr (CmmMachOp _ es) = mapM_ te_Expr es te_Expr (CmmRegOff r _) = te_Reg r te_Expr (CmmStackSlot _ _) = panic "te_Expr: CmmStackSlot not supported!" te_Reg :: CmmReg -> TE () te_Reg (CmmLocal l) = te_temp l te_Reg _ = return () -- --------------------------------------------------------------------- -- C types for MachReps cCast :: SDoc -> CmmExpr -> SDoc cCast ty expr = parens ty <> pprExpr1 expr cLoad :: CmmExpr -> CmmType -> SDoc cLoad expr rep = sdocWithPlatform $ \platform -> if bewareLoadStoreAlignment (platformArch platform) then let decl = machRepCType rep <+> text "x" <> semi struct = text "struct" <+> braces (decl) packed_attr = text "__attribute__((packed))" cast = parens (struct <+> packed_attr <> char '*') in parens (cast <+> pprExpr1 expr) <> text "->x" else char '*' <> parens (cCast (machRepPtrCType rep) expr) where -- On these platforms, unaligned loads are known to cause problems bewareLoadStoreAlignment ArchAlpha = True bewareLoadStoreAlignment ArchMipseb = True bewareLoadStoreAlignment ArchMipsel = True bewareLoadStoreAlignment (ArchARM {}) = True bewareLoadStoreAlignment ArchARM64 = True bewareLoadStoreAlignment ArchSPARC = True bewareLoadStoreAlignment ArchSPARC64 = True -- Pessimistically assume that they will also cause problems -- on unknown arches bewareLoadStoreAlignment ArchUnknown = True bewareLoadStoreAlignment _ = False isCmmWordType :: DynFlags -> CmmType -> Bool -- True of GcPtrReg/NonGcReg of native word size isCmmWordType dflags ty = not (isFloatType ty) && typeWidth ty == wordWidth dflags -- This is for finding the types of foreign call arguments. For a pointer -- argument, we always cast the argument to (void *), to avoid warnings from -- the C compiler. machRepHintCType :: CmmType -> ForeignHint -> SDoc machRepHintCType _ AddrHint = text "void *" machRepHintCType rep SignedHint = machRep_S_CType (typeWidth rep) machRepHintCType rep _other = machRepCType rep machRepPtrCType :: CmmType -> SDoc machRepPtrCType r = sdocWithDynFlags $ \dflags -> if isCmmWordType dflags r then text "P_" else machRepCType r <> char '*' machRepCType :: CmmType -> SDoc machRepCType ty | isFloatType ty = machRep_F_CType w | otherwise = machRep_U_CType w where w = typeWidth ty machRep_F_CType :: Width -> SDoc machRep_F_CType W32 = text "StgFloat" -- ToDo: correct? machRep_F_CType W64 = text "StgDouble" machRep_F_CType _ = panic "machRep_F_CType" machRep_U_CType :: Width -> SDoc machRep_U_CType w = sdocWithDynFlags $ \dflags -> case w of _ | w == wordWidth dflags -> text "W_" W8 -> text "StgWord8" W16 -> text "StgWord16" W32 -> text "StgWord32" W64 -> text "StgWord64" _ -> panic "machRep_U_CType" machRep_S_CType :: Width -> SDoc machRep_S_CType w = sdocWithDynFlags $ \dflags -> case w of _ | w == wordWidth dflags -> text "I_" W8 -> text "StgInt8" W16 -> text "StgInt16" W32 -> text "StgInt32" W64 -> text "StgInt64" _ -> panic "machRep_S_CType" -- --------------------------------------------------------------------- -- print strings as valid C strings pprStringInCStyle :: [Word8] -> SDoc pprStringInCStyle s = doubleQuotes (text (concatMap charToC s)) -- --------------------------------------------------------------------------- -- Initialising static objects with floating-point numbers. We can't -- just emit the floating point number, because C will cast it to an int -- by rounding it. We want the actual bit-representation of the float. -- -- Consider a concrete C example: -- double d = 2.5e-10; -- float f = 2.5e-10f; -- -- int * i2 = &d; printf ("i2: %08X %08X\n", i2[0], i2[1]); -- long long * l = &d; printf (" l: %016llX\n", l[0]); -- int * i = &f; printf (" i: %08X\n", i[0]); -- Result on 64-bit LE (x86_64): -- i2: E826D695 3DF12E0B -- l: 3DF12E0BE826D695 -- i: 2F89705F -- Result on 32-bit BE (m68k): -- i2: 3DF12E0B E826D695 -- l: 3DF12E0BE826D695 -- i: 2F89705F -- -- The trick here is to notice that binary representation does not -- change much: only Word32 values get swapped on LE hosts / targets. -- This is a hack to turn the floating point numbers into ints that we -- can safely initialise to static locations. castFloatToWord32Array :: STUArray s Int Float -> ST s (STUArray s Int Word32) castFloatToWord32Array = U.castSTUArray castDoubleToWord64Array :: STUArray s Int Double -> ST s (STUArray s Int Word64) castDoubleToWord64Array = U.castSTUArray floatToWord :: DynFlags -> Rational -> CmmLit floatToWord dflags r = runST (do arr <- newArray_ ((0::Int),0) writeArray arr 0 (fromRational r) arr' <- castFloatToWord32Array arr w32 <- readArray arr' 0 return (CmmInt (toInteger w32 `shiftL` wo) (wordWidth dflags)) ) where wo | wordWidth dflags == W64 , wORDS_BIGENDIAN dflags = 32 | otherwise = 0 floatPairToWord :: DynFlags -> Rational -> Rational -> CmmLit floatPairToWord dflags r1 r2 = runST (do arr <- newArray_ ((0::Int),1) writeArray arr 0 (fromRational r1) writeArray arr 1 (fromRational r2) arr' <- castFloatToWord32Array arr w32_1 <- readArray arr' 0 w32_2 <- readArray arr' 1 return (pprWord32Pair w32_1 w32_2) ) where pprWord32Pair w32_1 w32_2 | wORDS_BIGENDIAN dflags = CmmInt ((shiftL i1 32) .|. i2) W64 | otherwise = CmmInt ((shiftL i2 32) .|. i1) W64 where i1 = toInteger w32_1 i2 = toInteger w32_2 doubleToWords :: DynFlags -> Rational -> [CmmLit] doubleToWords dflags r = runST (do arr <- newArray_ ((0::Int),1) writeArray arr 0 (fromRational r) arr' <- castDoubleToWord64Array arr w64 <- readArray arr' 0 return (pprWord64 w64) ) where targetWidth = wordWidth dflags targetBE = wORDS_BIGENDIAN dflags pprWord64 w64 | targetWidth == W64 = [ CmmInt (toInteger w64) targetWidth ] | targetWidth == W32 = [ CmmInt (toInteger targetW1) targetWidth , CmmInt (toInteger targetW2) targetWidth ] | otherwise = panic "doubleToWords.pprWord64" where (targetW1, targetW2) | targetBE = (wHi, wLo) | otherwise = (wLo, wHi) wHi = w64 `shiftR` 32 wLo = w64 .&. 0xFFFFffff -- --------------------------------------------------------------------------- -- Utils wordShift :: DynFlags -> Int wordShift dflags = widthInLog (wordWidth dflags) commafy :: [SDoc] -> SDoc commafy xs = hsep $ punctuate comma xs -- Print in C hex format: 0x13fa pprHexVal :: Integer -> Width -> SDoc pprHexVal w rep | w < 0 = parens (char '-' <> text "0x" <> intToDoc (-w) <> repsuffix rep) | otherwise = text "0x" <> intToDoc w <> repsuffix rep where -- type suffix for literals: -- Integer literals are unsigned in Cmm/C. We explicitly cast to -- signed values for doing signed operations, but at all other -- times values are unsigned. This also helps eliminate occasional -- warnings about integer overflow from gcc. repsuffix W64 = sdocWithDynFlags $ \dflags -> if cINT_SIZE dflags == 8 then char 'U' else if cLONG_SIZE dflags == 8 then text "UL" else if cLONG_LONG_SIZE dflags == 8 then text "ULL" else panic "pprHexVal: Can't find a 64-bit type" repsuffix _ = char 'U' intToDoc :: Integer -> SDoc intToDoc i = case truncInt i of 0 -> char '0' v -> go v -- We need to truncate value as Cmm backend does not drop -- redundant bits to ease handling of negative values. -- Thus the following Cmm code on 64-bit arch, like amd64: -- CInt v; -- v = {something}; -- if (v == %lobits32(-1)) { ... -- leads to the following C code: -- StgWord64 v = (StgWord32)({something}); -- if (v == 0xFFFFffffFFFFffffU) { ... -- Such code is incorrect as it promotes both operands to StgWord64 -- and the whole condition is always false. truncInt :: Integer -> Integer truncInt i = case rep of W8 -> i `rem` (2^(8 :: Int)) W16 -> i `rem` (2^(16 :: Int)) W32 -> i `rem` (2^(32 :: Int)) W64 -> i `rem` (2^(64 :: Int)) _ -> panic ("pprHexVal/truncInt: C backend can't encode " ++ show rep ++ " literals") go 0 = empty go w' = go q <> dig where (q,r) = w' `quotRem` 16 dig | r < 10 = char (chr (fromInteger r + ord '0')) | otherwise = char (chr (fromInteger r - 10 + ord 'a'))