----------------------------------------------------------------------------- -- -- 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 -- -- 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. -- -- ToDo: save/restore volatile registers around calls. module PprC ( writeCs, pprStringInCStyle ) where #include "HsVersions.h" -- Cmm stuff import Cmm import CLabel import MachOp import ForeignCall -- Utils import DynFlags import Unique import UniqSet import FiniteMap import UniqFM import FastString import Outputable import Constants -- The rest import Data.List import Data.Bits import Data.Char import System.IO import Data.Word #ifdef DEBUG import PprCmm () -- instances only -- import Debug.Trace #endif import Data.Array.ST import Control.Monad.ST #if x86_64_TARGET_ARCH import StaticFlags ( opt_Unregisterised ) #endif #if defined(alpha_TARGET_ARCH) || defined(mips_TARGET_ARCH) || defined(mipsel_TARGET_ARCH) || defined(arm_TARGET_ARCH) #define BEWARE_LOAD_STORE_ALIGNMENT #endif -- -------------------------------------------------------------------------- -- Top level pprCs :: DynFlags -> [Cmm] -> SDoc pprCs dflags cmms = pprCode CStyle (vcat $ map (\c -> split_marker $$ pprC c) cmms) where split_marker | dopt Opt_SplitObjs dflags = ptext SLIT("__STG_SPLIT_MARKER") | otherwise = empty writeCs :: DynFlags -> Handle -> [Cmm] -> IO () writeCs dflags handle cmms = printForC handle (pprCs dflags cmms) -- -------------------------------------------------------------------------- -- Now do some real work -- -- for fun, we could call cmmToCmm over the tops... -- pprC :: Cmm -> SDoc pprC (Cmm tops) = vcat $ intersperse (text "") $ map pprTop tops -- -- top level procs -- pprTop :: CmmTop -> SDoc pprTop (CmmProc info clbl _params blocks) = (if not (null info) then pprDataExterns info $$ pprWordArray (entryLblToInfoLbl clbl) info else empty) $$ (case blocks of [] -> empty -- the first block doesn't get a label: (BasicBlock _ stmts : rest) -> vcat [ text "", extern_decls, (if (externallyVisibleCLabel clbl) then mkFN_ else mkIF_) (pprCLabel clbl) <+> lbrace, nest 8 temp_decls, nest 8 mkFB_, nest 8 (vcat (map pprStmt stmts)) $$ vcat (map pprBBlock rest), nest 8 mkFE_, rbrace ] ) where (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 _ds@[CmmDataLabel lbl, CmmString str]) = hcat [ pprLocalness lbl, ptext SLIT("char "), pprCLabel lbl, ptext SLIT("[] = "), pprStringInCStyle str, semi ] pprTop (CmmData _section _ds@[CmmDataLabel lbl, CmmUninitialised size]) = hcat [ pprLocalness lbl, ptext SLIT("char "), pprCLabel lbl, brackets (int size), semi ] pprTop top@(CmmData _section (CmmDataLabel lbl : lits)) = pprDataExterns lits $$ pprWordArray lbl lits -- these shouldn't appear? pprTop (CmmData _ _) = panic "PprC.pprTop: can't handle this data" -- -------------------------------------------------------------------------- -- BasicBlocks are self-contained entities: they always end in a jump. -- -- Like nativeGen/AsmCodeGen, we could probably reorder blocks to turn -- as many jumps as possible into fall throughs. -- pprBBlock :: CmmBasicBlock -> SDoc pprBBlock (BasicBlock lbl stmts) = if null stmts then pprTrace "pprC.pprBBlock: curious empty code block for" (pprBlockId lbl) empty else nest 4 (pprBlockId lbl <> colon) $$ nest 8 (vcat (map pprStmt stmts)) -- -------------------------------------------------------------------------- -- Info tables. Just arrays of words. -- See codeGen/ClosureInfo, and nativeGen/PprMach pprWordArray :: CLabel -> [CmmStatic] -> SDoc pprWordArray lbl ds = hcat [ pprLocalness lbl, ptext SLIT("StgWord") , space, pprCLabel lbl, ptext SLIT("[] = {") ] $$ nest 8 (commafy (pprStatics ds)) $$ ptext SLIT("};") -- -- has to be static, if it isn't globally visible -- pprLocalness :: CLabel -> SDoc pprLocalness lbl | not $ externallyVisibleCLabel lbl = ptext SLIT("static ") | otherwise = empty -- -------------------------------------------------------------------------- -- Statements. -- pprStmt :: CmmStmt -> SDoc pprStmt stmt = case stmt of CmmNop -> empty CmmComment s -> (hang (ptext SLIT("/*")) 3 (ftext s)) $$ ptext SLIT("*/") CmmAssign dest src -> pprAssign dest src CmmStore dest src | rep == I64 && wordRep /= I64 -> ptext SLIT("ASSIGN_Word64") <> parens (mkP_ <> pprExpr1 dest <> comma <> pprExpr src) <> semi | rep == F64 && wordRep /= I64 -> ptext SLIT("ASSIGN_DBL") <> parens (mkP_ <> pprExpr1 dest <> comma <> pprExpr src) <> semi | otherwise -> hsep [ pprExpr (CmmLoad dest rep), equals, pprExpr src <> semi ] where rep = cmmExprRep src CmmCall (CmmForeignCall fn cconv) results args volatile -> -- Controversial: leave this out for now. -- pprUndef fn $$ pprCall ppr_fn cconv results args volatile where ppr_fn = case fn of CmmLit (CmmLabel lbl) -> pprCLabel lbl _other -> parens (cCast (pprCFunType cconv results args) fn) -- for a dynamic call, cast the expression to -- a function of the right type (we hope). -- we #undef a function before calling it: the FFI is supposed to be -- an interface specifically to C, not to C+CPP. For one thing, this -- makes the via-C route more compatible with the NCG. If macros -- are being used for optimisation, then inline functions are probably -- better anyway. pprUndef (CmmLit (CmmLabel lbl)) = ptext SLIT("#undef") <+> pprCLabel lbl pprUndef _ = empty CmmCall (CmmPrim op) results args volatile -> pprCall ppr_fn CCallConv results args volatile where ppr_fn = pprCallishMachOp_for_C op CmmBranch ident -> pprBranch ident CmmCondBranch expr ident -> pprCondBranch expr ident CmmJump lbl _params -> mkJMP_(pprExpr lbl) <> semi CmmSwitch arg ids -> pprSwitch arg ids pprCFunType :: CCallConv -> [(CmmReg,MachHint)] -> [(CmmExpr,MachHint)] -> SDoc pprCFunType cconv ress args = hcat [ res_type ress, parens (text (ccallConvAttribute cconv) <> char '*'), parens (commafy (map arg_type args)) ] where res_type [] = ptext SLIT("void") res_type [(one,hint)] = machRepHintCType (cmmRegRep one) hint arg_type (expr,hint) = machRepHintCType (cmmExprRep expr) hint -- --------------------------------------------------------------------- -- unconditional branches pprBranch :: BlockId -> SDoc pprBranch ident = ptext SLIT("goto") <+> pprBlockId ident <> semi -- --------------------------------------------------------------------- -- conditional branches to local labels pprCondBranch :: CmmExpr -> BlockId -> SDoc pprCondBranch expr ident = hsep [ ptext SLIT("if") , parens(pprExpr expr) , ptext SLIT("goto") , (pprBlockId ident) <> semi ] -- --------------------------------------------------------------------- -- a local table branch -- -- we find the fall-through cases -- -- N.B. we remove Nothing's from the list of branches, as they are -- 'undefined'. However, they may be defined one day, so we better -- document this behaviour. -- pprSwitch :: CmmExpr -> [ Maybe BlockId ] -> SDoc pprSwitch e maybe_ids = let pairs = [ (ix, ident) | (ix,Just ident) <- zip [0..] maybe_ids ] pairs2 = [ (map fst as, snd (head as)) | as <- groupBy sndEq pairs ] in (hang (ptext SLIT("switch") <+> parens ( pprExpr e ) <+> lbrace) 4 (vcat ( map caseify pairs2 ))) $$ rbrace where sndEq (_,x) (_,y) = x == y -- fall through case caseify (ix:ixs, ident) = vcat (map do_fallthrough ixs) $$ final_branch ix where do_fallthrough ix = hsep [ ptext SLIT("case") , pprHexVal ix wordRep <> colon , ptext SLIT("/* fall through */") ] final_branch ix = hsep [ ptext SLIT("case") , pprHexVal ix wordRep <> colon , ptext SLIT("goto") , (pprBlockId ident) <> semi ] -- --------------------------------------------------------------------- -- 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 (cmmExprRep 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 I64 | wordRep /= I64 -> ptext SLIT("PK_Word64") <> parens (mkP_ <> pprExpr1 e) CmmLoad e F64 | wordRep /= I64 -> ptext SLIT("PK_DBL") <> parens (mkP_ <> pprExpr1 e) CmmLoad (CmmReg r) rep | isPtrReg r && rep == wordRep -> char '*' <> pprAsPtrReg r CmmLoad (CmmRegOff r 0) rep | isPtrReg r && rep == wordRep -> char '*' <> pprAsPtrReg r CmmLoad (CmmRegOff r off) rep | isPtrReg r && rep == wordRep -- ToDo: check that the offset is a word multiple? -> pprAsPtrReg r <> brackets (ppr (off `shiftR` wordShift)) CmmLoad expr rep -> -- the general case: cLoad expr rep CmmReg reg -> pprCastReg reg CmmRegOff reg 0 -> pprCastReg reg CmmRegOff reg i | i > 0 -> pprRegOff (char '+') i | otherwise -> pprRegOff (char '-') (-i) where pprRegOff op i' = pprCastReg reg <> op <> int i' CmmMachOp mop args -> pprMachOpApp mop args 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 = ptext SLIT("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' 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 pprArg e | signedOp mop = cCast (machRepSignedCType (cmmExprRep e)) e | otherwise = pprExpr1 e -- -------------------------------------------------------------------------- -- Literals pprLit :: CmmLit -> SDoc pprLit lit = case lit of CmmInt i rep -> pprHexVal i rep CmmFloat f rep -> parens (machRepCType rep) <> (rational f) CmmLabel clbl -> mkW_ <> pprCLabelAddr clbl CmmLabelOff clbl i -> mkW_ <> pprCLabelAddr clbl <> char '+' <> int i CmmLabelDiffOff clbl1 clbl2 i -- WARNING: -- * the lit must occur in the info table clbl2 -- * clbl1 must be an SRT, a slow entry point or a large bitmap -- The Mangler is expected to convert any reference to an SRT, -- a slow entry point or a large bitmap -- from an info table to an offset. -> mkW_ <> pprCLabelAddr clbl1 <> char '+' <> int i pprCLabelAddr lbl = char '&' <> pprCLabel 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 :: [CmmStatic] -> [SDoc] pprStatics [] = [] pprStatics (CmmStaticLit (CmmFloat f F32) : rest) = pprLit1 (floatToWord f) : pprStatics rest pprStatics (CmmStaticLit (CmmFloat f F64) : rest) = map pprLit1 (doubleToWords f) ++ pprStatics rest pprStatics (CmmStaticLit (CmmInt i I64) : rest) | machRepByteWidth I32 == wORD_SIZE #ifdef WORDS_BIGENDIAN = pprStatics (CmmStaticLit (CmmInt q I32) : CmmStaticLit (CmmInt r I32) : rest) #else = pprStatics (CmmStaticLit (CmmInt r I32) : CmmStaticLit (CmmInt q I32) : rest) #endif where r = i .&. 0xffffffff q = i `shiftR` 32 pprStatics (CmmStaticLit (CmmInt i rep) : rest) | machRepByteWidth rep /= wORD_SIZE = panic "pprStatics: cannot emit a non-word-sized static literal" pprStatics (CmmStaticLit lit : rest) = pprLit1 lit : pprStatics rest pprStatics (other : rest) = pprPanic "pprWord" (pprStatic other) pprStatic :: CmmStatic -> SDoc pprStatic s = case s of CmmStaticLit lit -> nest 4 (pprLit lit) CmmAlign i -> nest 4 (ptext SLIT("/* align */") <+> int i) CmmDataLabel clbl -> pprCLabel clbl <> colon 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 _ -> ptext SLIT("==") MO_Ne _ -> ptext SLIT("!=") MO_Mul _ -> char '*' MO_S_Quot _ -> char '/' MO_S_Rem _ -> char '%' MO_S_Neg _ -> char '-' MO_U_Quot _ -> char '/' MO_U_Rem _ -> char '%' -- Signed comparisons (floating-point comparisons also use these) -- & Unsigned comparisons MO_S_Ge _ -> ptext SLIT(">=") MO_S_Le _ -> ptext SLIT("<=") MO_S_Gt _ -> char '>' MO_S_Lt _ -> char '<' MO_U_Ge _ -> ptext SLIT(">=") MO_U_Le _ -> ptext SLIT("<=") MO_U_Gt _ -> char '>' MO_U_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 _ -> ptext SLIT("<<") MO_U_Shr _ -> ptext SLIT(">>") -- unsigned shift right MO_S_Shr _ -> ptext SLIT(">>") -- signed shift right -- Conversions. Some of these will be NOPs. -- Floating-point conversions use the signed variant. -- We won't know to generate (void*) casts here, but maybe from -- context elsewhere -- noop casts MO_U_Conv I8 I8 -> empty MO_U_Conv I16 I16 -> empty MO_U_Conv I32 I32 -> empty MO_U_Conv I64 I64 -> empty MO_U_Conv I128 I128 -> empty MO_S_Conv I8 I8 -> empty MO_S_Conv I16 I16 -> empty MO_S_Conv I32 I32 -> empty MO_S_Conv I64 I64 -> empty MO_S_Conv I128 I128 -> empty MO_U_Conv _from to -> parens (machRepCType to) MO_S_Conv _from to -> parens (machRepSignedCType to) _ -> panic "PprC.pprMachOp_for_C: unknown machop" signedOp :: MachOp -> Bool 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_S_Conv _ _) = True signedOp _ = False -- --------------------------------------------------------------------- -- tend to be implemented by foreign calls pprCallishMachOp_for_C :: CallishMachOp -> SDoc pprCallishMachOp_for_C mop = case mop of MO_F64_Pwr -> ptext SLIT("pow") MO_F64_Sin -> ptext SLIT("sin") MO_F64_Cos -> ptext SLIT("cos") MO_F64_Tan -> ptext SLIT("tan") MO_F64_Sinh -> ptext SLIT("sinh") MO_F64_Cosh -> ptext SLIT("cosh") MO_F64_Tanh -> ptext SLIT("tanh") MO_F64_Asin -> ptext SLIT("asin") MO_F64_Acos -> ptext SLIT("acos") MO_F64_Atan -> ptext SLIT("atan") MO_F64_Log -> ptext SLIT("log") MO_F64_Exp -> ptext SLIT("exp") MO_F64_Sqrt -> ptext SLIT("sqrt") MO_F32_Pwr -> ptext SLIT("powf") MO_F32_Sin -> ptext SLIT("sinf") MO_F32_Cos -> ptext SLIT("cosf") MO_F32_Tan -> ptext SLIT("tanf") MO_F32_Sinh -> ptext SLIT("sinhf") MO_F32_Cosh -> ptext SLIT("coshf") MO_F32_Tanh -> ptext SLIT("tanhf") MO_F32_Asin -> ptext SLIT("asinf") MO_F32_Acos -> ptext SLIT("acosf") MO_F32_Atan -> ptext SLIT("atanf") MO_F32_Log -> ptext SLIT("logf") MO_F32_Exp -> ptext SLIT("expf") MO_F32_Sqrt -> ptext SLIT("sqrtf") MO_WriteBarrier -> ptext SLIT("write_barrier") -- --------------------------------------------------------------------- -- Useful #defines -- mkJMP_, mkFN_, mkIF_ :: SDoc -> SDoc mkJMP_ i = ptext SLIT("JMP_") <> parens i mkFN_ i = ptext SLIT("FN_") <> parens i -- externally visible function mkIF_ i = ptext SLIT("IF_") <> parens i -- locally visible mkFB_, mkFE_ :: SDoc mkFB_ = ptext SLIT("FB_") -- function code begin mkFE_ = ptext SLIT("FE_") -- function code end -- from includes/Stg.h -- mkC_,mkW_,mkP_,mkPP_,mkI_,mkA_,mkD_,mkF_,mkB_,mkL_,mkLI_,mkLW_ :: SDoc mkC_ = ptext SLIT("(C_)") -- StgChar mkW_ = ptext SLIT("(W_)") -- StgWord mkP_ = ptext SLIT("(P_)") -- StgWord* mkPP_ = ptext SLIT("(PP_)") -- P_* mkI_ = ptext SLIT("(I_)") -- StgInt mkA_ = ptext SLIT("(A_)") -- StgAddr mkD_ = ptext SLIT("(D_)") -- const StgWord* mkF_ = ptext SLIT("(F_)") -- StgFunPtr mkB_ = ptext SLIT("(B_)") -- StgByteArray mkL_ = ptext SLIT("(L_)") -- StgClosurePtr mkLI_ = ptext SLIT("(LI_)") -- StgInt64 mkLW_ = ptext SLIT("(LW_)") -- StgWord64 -- --------------------------------------------------------------------- -- -- Assignments -- -- Generating assignments is what we're all about, here -- pprAssign :: 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 r1 (CmmRegOff r2 off) | isPtrReg r1 && isPtrReg r2 && (off `rem` wORD_SIZE == 0) = hcat [ pprAsPtrReg r1, equals, pprAsPtrReg r2, op, int off', semi ] where off1 = off `shiftR` wordShift (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 = pprReg r1 <> ptext SLIT(" = ") <> mkP_ <> pprExpr1 r2 <> semi | Just ty <- strangeRegType r1 = pprReg r1 <> ptext SLIT(" = ") <> parens ty <> pprExpr1 r2 <> semi | otherwise = pprReg r1 <> ptext SLIT(" = ") <> pprExpr r2 <> semi -- --------------------------------------------------------------------- -- Registers 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 isPtrReg :: CmmReg -> Bool isPtrReg (CmmLocal _) = False isPtrReg (CmmGlobal (VanillaReg n)) = True -- 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 (cmmRegRep reg)), so it has to be cast. isStrangeTypeReg :: CmmReg -> Bool isStrangeTypeReg (CmmLocal _) = False isStrangeTypeReg (CmmGlobal g) = isStrangeTypeGlobal g isStrangeTypeGlobal :: GlobalReg -> Bool isStrangeTypeGlobal CurrentTSO = True isStrangeTypeGlobal CurrentNursery = True isStrangeTypeGlobal BaseReg = True isStrangeTypeGlobal r = isFixedPtrGlobalReg r strangeRegType :: CmmReg -> Maybe SDoc strangeRegType (CmmGlobal CurrentTSO) = Just (ptext SLIT("struct StgTSO_ *")) strangeRegType (CmmGlobal CurrentNursery) = Just (ptext SLIT("struct bdescr_ *")) strangeRegType (CmmGlobal BaseReg) = Just (ptext SLIT("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)) = char 'R' <> int n <> ptext SLIT(".p") pprAsPtrReg other_reg = pprReg other_reg pprGlobalReg :: GlobalReg -> SDoc pprGlobalReg gr = case gr of VanillaReg n -> char 'R' <> int n <> ptext SLIT(".w") FloatReg n -> char 'F' <> int n DoubleReg n -> char 'D' <> int n LongReg n -> char 'L' <> int n Sp -> ptext SLIT("Sp") SpLim -> ptext SLIT("SpLim") Hp -> ptext SLIT("Hp") HpLim -> ptext SLIT("HpLim") CurrentTSO -> ptext SLIT("CurrentTSO") CurrentNursery -> ptext SLIT("CurrentNursery") HpAlloc -> ptext SLIT("HpAlloc") BaseReg -> ptext SLIT("BaseReg") GCEnter1 -> ptext SLIT("stg_gc_enter_1") GCFun -> ptext SLIT("stg_gc_fun") pprLocalReg :: LocalReg -> SDoc pprLocalReg (LocalReg uniq _rep) = char '_' <> ppr uniq -- ----------------------------------------------------------------------------- -- Foreign Calls pprCall :: SDoc -> CCallConv -> [(CmmReg,MachHint)] -> [(CmmExpr,MachHint)] -> Maybe [GlobalReg] -> SDoc pprCall ppr_fn cconv results args vols | not (is_cish cconv) = panic "pprCall: unknown calling convention" | otherwise = save vols $$ ptext SLIT("CALLER_SAVE_SYSTEM") $$ #if x86_64_TARGET_ARCH -- HACK around gcc optimisations. -- x86_64 needs a __DISCARD__() here, to create a barrier between -- putting the arguments into temporaries and passing the arguments -- to the callee, because the argument expressions may refer to -- machine registers that are also used for passing arguments in the -- C calling convention. (if (not opt_Unregisterised) then ptext SLIT("__DISCARD__();") else empty) $$ #endif ppr_assign results (ppr_fn <> parens (commafy (map pprArg args))) <> semi $$ ptext SLIT("CALLER_RESTORE_SYSTEM") $$ restore vols where ppr_assign [] rhs = rhs ppr_assign [(reg@(CmmGlobal BaseReg), hint)] rhs | Just ty <- strangeRegType reg = ptext SLIT("ASSIGN_BaseReg") <> parens (parens ty <> rhs) -- BaseReg is special, sometimes it isn't an lvalue and we -- can't assign to it. ppr_assign [(one,hint)] rhs | Just ty <- strangeRegType one = pprReg one <> ptext SLIT(" = ") <> parens ty <> rhs | otherwise = pprReg one <> ptext SLIT(" = ") <> pprUnHint hint (cmmRegRep one) <> rhs ppr_assign _other _rhs = panic "pprCall: multiple results" pprArg (expr, PtrHint) = cCast (ptext SLIT("void *")) expr -- see comment by machRepHintCType below pprArg (expr, SignedHint) = cCast (machRepSignedCType (cmmExprRep expr)) expr pprArg (expr, _other) = pprExpr expr pprUnHint PtrHint rep = parens (machRepCType rep) pprUnHint SignedHint rep = parens (machRepCType rep) pprUnHint _ _ = empty save = save_restore SLIT("CALLER_SAVE") restore = save_restore SLIT("CALLER_RESTORE") -- Nothing says "I don't know what's live; save everything" -- CALLER_SAVE_USER is defined in ghc/includes/Regs.h save_restore txt Nothing = ptext txt <> ptext SLIT("_USER") save_restore txt (Just these) = vcat (map saveRestoreGlobal these) where saveRestoreGlobal r = ptext txt <> char '_' <> pprGlobalRegName r pprGlobalRegName :: GlobalReg -> SDoc pprGlobalRegName gr = case gr of VanillaReg n -> char 'R' <> int n -- without the .w suffix _ -> pprGlobalReg gr -- Currently we only have these two calling conventions, but this might -- change in the future... is_cish CCallConv = True is_cish StdCallConv = True -- --------------------------------------------------------------------- -- Find and print local and external declarations for a list of -- Cmm statements. -- pprTempAndExternDecls :: [CmmBasicBlock] -> (SDoc{-temps-}, SDoc{-externs-}) pprTempAndExternDecls stmts = (vcat (map pprTempDecl (eltsUFM temps)), vcat (map (pprExternDecl False{-ToDo-}) (keysFM lbls))) where (temps, lbls) = runTE (mapM_ te_BB stmts) pprDataExterns :: [CmmStatic] -> SDoc pprDataExterns statics = vcat (map (pprExternDecl False{-ToDo-}) (keysFM lbls)) where (_, lbls) = runTE (mapM_ te_Static statics) pprTempDecl :: LocalReg -> SDoc pprTempDecl l@(LocalReg _uniq rep) = hcat [ machRepCType rep, space, pprLocalReg l, semi ] pprExternDecl :: Bool -> CLabel -> SDoc pprExternDecl in_srt lbl -- do not print anything for "known external" things | not (needsCDecl lbl) = empty | otherwise = hcat [ visibility, label_type (labelType lbl), lparen, dyn_wrapper (pprCLabel lbl), text ");" ] where dyn_wrapper d | in_srt && labelDynamic lbl = text "DLL_IMPORT_DATA_VAR" <> parens d | otherwise = d label_type CodeLabel = ptext SLIT("F_") label_type DataLabel = ptext SLIT("I_") visibility | externallyVisibleCLabel lbl = char 'E' | otherwise = char 'I' type TEState = (UniqSet LocalReg, FiniteMap CLabel ()) newtype TE a = TE { unTE :: TEState -> (a, TEState) } instance Monad TE where TE m >>= k = TE $ \s -> case m s of (a, s') -> unTE (k a) s' return a = TE $ \s -> (a, s) te_lbl :: CLabel -> TE () te_lbl lbl = TE $ \(temps,lbls) -> ((), (temps, addToFM lbls lbl ())) te_temp :: LocalReg -> TE () te_temp r = TE $ \(temps,lbls) -> ((), (addOneToUniqSet temps r, lbls)) runTE :: TE () -> TEState runTE (TE m) = snd (m (emptyUniqSet, emptyFM)) te_Static :: CmmStatic -> TE () te_Static (CmmStaticLit lit) = te_Lit lit te_Static _ = return () te_BB :: CmmBasicBlock -> TE () te_BB (BasicBlock _ ss) = mapM_ te_Stmt ss te_Lit :: CmmLit -> TE () te_Lit (CmmLabel l) = te_lbl l te_Lit (CmmLabelOff l _) = te_lbl l te_Lit (CmmLabelDiffOff l1 l2 _) = te_lbl l1 te_Lit _ = return () te_Stmt :: CmmStmt -> 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 (CmmCall _ rs es _) = mapM_ (te_Reg.fst) rs >> mapM_ (te_Expr.fst) es te_Stmt (CmmCondBranch e _) = te_Expr e te_Stmt (CmmSwitch e _) = te_Expr e te_Stmt (CmmJump e _) = te_Expr e te_Stmt _ = 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_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 -> MachRep -> SDoc #ifdef BEWARE_LOAD_STORE_ALIGNMENT cLoad expr rep = let decl = machRepCType rep <+> ptext SLIT("x") <> semi struct = ptext SLIT("struct") <+> braces (decl) packed_attr = ptext SLIT("__attribute__((packed))") cast = parens (struct <+> packed_attr <> char '*') in parens (cast <+> pprExpr1 expr) <> ptext SLIT("->x") #else cLoad expr rep = char '*' <> parens (cCast (machRepPtrCType rep) expr) #endif -- 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 :: MachRep -> MachHint -> SDoc machRepHintCType rep PtrHint = ptext SLIT("void *") machRepHintCType rep SignedHint = machRepSignedCType rep machRepHintCType rep _other = machRepCType rep machRepPtrCType :: MachRep -> SDoc machRepPtrCType r | r == wordRep = ptext SLIT("P_") | otherwise = machRepCType r <> char '*' machRepCType :: MachRep -> SDoc machRepCType r | r == wordRep = ptext SLIT("W_") | otherwise = sized_type where sized_type = case r of I8 -> ptext SLIT("StgWord8") I16 -> ptext SLIT("StgWord16") I32 -> ptext SLIT("StgWord32") I64 -> ptext SLIT("StgWord64") F32 -> ptext SLIT("StgFloat") -- ToDo: correct? F64 -> ptext SLIT("StgDouble") _ -> panic "machRepCType" machRepSignedCType :: MachRep -> SDoc machRepSignedCType r | r == wordRep = ptext SLIT("I_") | otherwise = sized_type where sized_type = case r of I8 -> ptext SLIT("StgInt8") I16 -> ptext SLIT("StgInt16") I32 -> ptext SLIT("StgInt32") I64 -> ptext SLIT("StgInt64") F32 -> ptext SLIT("StgFloat") -- ToDo: correct? F64 -> ptext SLIT("StgDouble") _ -> panic "machRepCType" -- --------------------------------------------------------------------- -- print strings as valid C strings pprStringInCStyle :: [Word8] -> SDoc pprStringInCStyle s = doubleQuotes (text (concatMap charToC s)) charToC :: Word8 -> String charToC w = case chr (fromIntegral w) of '\"' -> "\\\"" '\'' -> "\\\'" '\\' -> "\\\\" c | c >= ' ' && c <= '~' -> [c] | otherwise -> ['\\', chr (ord '0' + ord c `div` 64), chr (ord '0' + ord c `div` 8 `mod` 8), chr (ord '0' + ord c `mod` 8)] -- --------------------------------------------------------------------------- -- 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. -- This is a hack to turn the floating point numbers into ints that we -- can safely initialise to static locations. big_doubles | machRepByteWidth F64 == 2 * wORD_SIZE = True | machRepByteWidth F64 == wORD_SIZE = False | otherwise = panic "big_doubles" castFloatToIntArray :: STUArray s Int Float -> ST s (STUArray s Int Int) castFloatToIntArray = castSTUArray castDoubleToIntArray :: STUArray s Int Double -> ST s (STUArray s Int Int) castDoubleToIntArray = castSTUArray -- floats are always 1 word floatToWord :: Rational -> CmmLit floatToWord r = runST (do arr <- newArray_ ((0::Int),0) writeArray arr 0 (fromRational r) arr' <- castFloatToIntArray arr i <- readArray arr' 0 return (CmmInt (toInteger i) wordRep) ) doubleToWords :: Rational -> [CmmLit] doubleToWords r | big_doubles -- doubles are 2 words = runST (do arr <- newArray_ ((0::Int),1) writeArray arr 0 (fromRational r) arr' <- castDoubleToIntArray arr i1 <- readArray arr' 0 i2 <- readArray arr' 1 return [ CmmInt (toInteger i1) wordRep , CmmInt (toInteger i2) wordRep ] ) | otherwise -- doubles are 1 word = runST (do arr <- newArray_ ((0::Int),0) writeArray arr 0 (fromRational r) arr' <- castDoubleToIntArray arr i <- readArray arr' 0 return [ CmmInt (toInteger i) wordRep ] ) -- --------------------------------------------------------------------------- -- Utils wordShift :: Int wordShift = machRepLogWidth wordRep commafy :: [SDoc] -> SDoc commafy xs = hsep $ punctuate comma xs -- Print in C hex format: 0x13fa pprHexVal :: Integer -> MachRep -> SDoc pprHexVal 0 _ = ptext SLIT("0x0") pprHexVal w rep | w < 0 = parens (char '-' <> ptext SLIT("0x") <> go (-w) <> repsuffix rep) | otherwise = ptext SLIT("0x") <> go 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. -- on 32-bit platforms, add "ULL" to 64-bit literals repsuffix I64 | wORD_SIZE == 4 = ptext SLIT("ULL") -- on 64-bit platforms with 32-bit int, add "L" to 64-bit literals repsuffix I64 | cINT_SIZE == 4 = ptext SLIT("UL") repsuffix _ = char 'U' 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'))