2 % (c) The University of Glasgow 2006
3 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
6 Storage manager representation of closures
8 This is here, rather than in ClosureInfo, just to keep nhc happy.
9 Other modules should access this info through ClosureInfo.
13 -- The above warning supression flag is a temporary kludge.
14 -- While working on this module you are encouraged to remove it and fix
15 -- any warnings in the module. See
16 -- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
22 hALF_WORD_SIZE, hALF_WORD_SIZE_IN_BITS,
25 -- Argument/return representations
26 CgRep(..), nonVoidArg,
27 argMachRep, primRepToCgRep, primRepHint,
28 isFollowableArg, isVoidArg,
29 isFloatingArg, is64BitArg,
30 separateByPtrFollowness,
31 cgRepSizeW, cgRepSizeB,
34 typeCgRep, idCgRep, tyConCgRep, typeHint,
36 -- Closure repesentation
37 SMRep(..), ClosureType(..),
39 fixedHdrSize, arrWordsHdrSize, arrPtrsHdrSize,
40 profHdrSize, thunkHdrSize,
41 smRepClosureType, smRepClosureTypeInt,
46 #include "HsVersions.h"
47 #include "../includes/MachDeps.h"
61 %************************************************************************
65 %************************************************************************
68 type WordOff = Int -- Word offset, or word count
69 type ByteOff = Int -- Byte offset, or byte count
72 StgWord is a type representing an StgWord on the target platform.
75 #if SIZEOF_HSWORD == 4
77 type StgHalfWord = Word16
78 hALF_WORD_SIZE = 2 :: ByteOff
79 hALF_WORD_SIZE_IN_BITS = 16 :: Int
80 #elif SIZEOF_HSWORD == 8
82 type StgHalfWord = Word32
83 hALF_WORD_SIZE = 4 :: ByteOff
84 hALF_WORD_SIZE_IN_BITS = 32 :: Int
86 #error unknown SIZEOF_HSWORD
91 %************************************************************************
95 %************************************************************************
97 An CgRep is an abstraction of a Type which tells the code generator
98 all it needs to know about the calling convention for arguments (and
99 results) of that type. In particular, the ArgReps of a function's
100 arguments are used to decide which of the RTS's generic apply
101 functions to call when applying an unknown function.
103 It contains more information than the back-end data type MachRep,
104 so one can easily convert from CgRep -> MachRep. (Except that
105 there's no MachRep for a VoidRep.)
108 pointers from non-pointers (we sort the pointers together
109 when building closures)
111 void from other types: a void argument is different from no argument
113 All 64-bit types map to the same CgRep, because they're passed in the
114 same register, but a PtrArg is still different from an NonPtrArg
115 because the function's entry convention has to take into account the
116 pointer-hood of arguments for the purposes of describing the stack on
117 entry to the garbage collector.
122 | PtrArg -- Word-sized Ptr
123 | NonPtrArg -- Word-sized non-pointer
124 | LongArg -- 64-bit non-pointer
125 | FloatArg -- 32-bit float
126 | DoubleArg -- 64-bit float
129 instance Outputable CgRep where
130 ppr VoidArg = ptext SLIT("V_")
131 ppr PtrArg = ptext SLIT("P_")
132 ppr NonPtrArg = ptext SLIT("I_")
133 ppr LongArg = ptext SLIT("L_")
134 ppr FloatArg = ptext SLIT("F_")
135 ppr DoubleArg = ptext SLIT("D_")
137 argMachRep :: CgRep -> MachRep
138 argMachRep PtrArg = wordRep
139 argMachRep NonPtrArg = wordRep
140 argMachRep LongArg = I64
141 argMachRep FloatArg = F32
142 argMachRep DoubleArg = F64
143 argMachRep VoidArg = panic "argMachRep:VoidRep"
145 primRepToCgRep :: PrimRep -> CgRep
146 primRepToCgRep VoidRep = VoidArg
147 primRepToCgRep PtrRep = PtrArg
148 primRepToCgRep IntRep = NonPtrArg
149 primRepToCgRep WordRep = NonPtrArg
150 primRepToCgRep Int64Rep = LongArg
151 primRepToCgRep Word64Rep = LongArg
152 primRepToCgRep AddrRep = NonPtrArg
153 primRepToCgRep FloatRep = FloatArg
154 primRepToCgRep DoubleRep = DoubleArg
156 primRepHint :: PrimRep -> MachHint
157 primRepHint VoidRep = panic "primRepHint:VoidRep"
158 primRepHint PtrRep = PtrHint
159 primRepHint IntRep = SignedHint
160 primRepHint WordRep = NoHint
161 primRepHint Int64Rep = SignedHint
162 primRepHint Word64Rep = NoHint
163 primRepHint AddrRep = PtrHint -- NB! PtrHint, but NonPtrArg
164 primRepHint FloatRep = FloatHint
165 primRepHint DoubleRep = FloatHint
167 idCgRep :: Id -> CgRep
168 idCgRep x = typeCgRep . idType $ x
170 tyConCgRep :: TyCon -> CgRep
171 tyConCgRep = primRepToCgRep . tyConPrimRep
173 typeCgRep :: Type -> CgRep
174 typeCgRep = primRepToCgRep . typePrimRep
176 typeHint :: Type -> MachHint
177 typeHint = primRepHint . typePrimRep
180 Whether or not the thing is a pointer that the garbage-collector
181 should follow. Or, to put it another (less confusing) way, whether
182 the object in question is a heap object.
184 Depending on the outcome, this predicate determines what stack
185 the pointer/object possibly will have to be saved onto, and the
186 computation of GC liveness info.
189 isFollowableArg :: CgRep -> Bool -- True <=> points to a heap object
190 isFollowableArg PtrArg = True
191 isFollowableArg other = False
193 isVoidArg :: CgRep -> Bool
194 isVoidArg VoidArg = True
195 isVoidArg other = False
197 nonVoidArg :: CgRep -> Bool
198 nonVoidArg VoidArg = False
199 nonVoidArg other = True
201 -- isFloatingArg is used to distinguish @Double@ and @Float@ which
202 -- cause inadvertent numeric conversions if you aren't jolly careful.
203 -- See codeGen/CgCon:cgTopRhsCon.
205 isFloatingArg :: CgRep -> Bool
206 isFloatingArg DoubleArg = True
207 isFloatingArg FloatArg = True
208 isFloatingArg _ = False
210 is64BitArg :: CgRep -> Bool
211 is64BitArg LongArg = True
216 separateByPtrFollowness :: [(CgRep,a)] -> ([(CgRep,a)], [(CgRep,a)])
217 -- Returns (ptrs, non-ptrs)
218 separateByPtrFollowness things
219 = sep_things things [] []
220 -- accumulating params for follow-able and don't-follow things...
222 sep_things [] bs us = (reverse bs, reverse us)
223 sep_things ((PtrArg,a):ts) bs us = sep_things ts ((PtrArg,a):bs) us
224 sep_things (t :ts) bs us = sep_things ts bs (t:us)
228 cgRepSizeB :: CgRep -> ByteOff
229 cgRepSizeB DoubleArg = dOUBLE_SIZE
230 cgRepSizeB LongArg = wORD64_SIZE
231 cgRepSizeB VoidArg = 0
232 cgRepSizeB _ = wORD_SIZE
234 cgRepSizeW :: CgRep -> ByteOff
235 cgRepSizeW DoubleArg = dOUBLE_SIZE `quot` wORD_SIZE
236 cgRepSizeW LongArg = wORD64_SIZE `quot` wORD_SIZE
237 cgRepSizeW VoidArg = 0
240 retAddrSizeW :: WordOff
241 retAddrSizeW = 1 -- One word
244 %************************************************************************
246 \subsubsection[SMRep-datatype]{@SMRep@---storage manager representation}
248 %************************************************************************
252 -- static closure have an extra static link field at the end.
253 = GenericRep -- GC routines consult sizes in info tbl
254 Bool -- True <=> This is a static closure. Affects how
255 -- we garbage-collect it
257 !Int -- # non-ptr words
258 ClosureType -- closure type
262 data ClosureType -- Corresponds 1-1 with the varieties of closures
263 -- implemented by the RTS. Compare with ghc/includes/ClosureTypes.h
271 Size of a closure header.
274 fixedHdrSize :: WordOff
275 fixedHdrSize = sTD_HDR_SIZE + profHdrSize + granHdrSize
277 profHdrSize :: WordOff
278 profHdrSize | opt_SccProfilingOn = pROF_HDR_SIZE
281 granHdrSize :: WordOff
282 granHdrSize | opt_GranMacros = gRAN_HDR_SIZE
285 arrWordsHdrSize :: ByteOff
286 arrWordsHdrSize = fixedHdrSize*wORD_SIZE + sIZEOF_StgArrWords_NoHdr
288 arrPtrsHdrSize :: ByteOff
289 arrPtrsHdrSize = fixedHdrSize*wORD_SIZE + sIZEOF_StgMutArrPtrs_NoHdr
291 -- Thunks have an extra header word on SMP, so the update doesn't
292 -- splat the payload.
293 thunkHdrSize :: WordOff
294 thunkHdrSize = fixedHdrSize + smp_hdr
295 where smp_hdr = sIZEOF_StgSMPThunkHeader `quot` wORD_SIZE
299 isStaticRep :: SMRep -> Bool
300 isStaticRep (GenericRep is_static _ _ _) = is_static
301 isStaticRep BlackHoleRep = False
305 #include "../includes/ClosureTypes.h"
306 -- Defines CONSTR, CONSTR_1_0 etc
308 -- krc: only called by tickyDynAlloc in CgTicky; return
309 -- Nothing for a black hole so we can at least make something work.
310 smRepClosureType :: SMRep -> Maybe ClosureType
311 smRepClosureType (GenericRep _ _ _ ty) = Just ty
312 smRepClosureType BlackHoleRep = Nothing
314 smRepClosureTypeInt :: SMRep -> StgHalfWord
315 smRepClosureTypeInt (GenericRep False 1 0 Constr) = CONSTR_1_0
316 smRepClosureTypeInt (GenericRep False 0 1 Constr) = CONSTR_0_1
317 smRepClosureTypeInt (GenericRep False 2 0 Constr) = CONSTR_2_0
318 smRepClosureTypeInt (GenericRep False 1 1 Constr) = CONSTR_1_1
319 smRepClosureTypeInt (GenericRep False 0 2 Constr) = CONSTR_0_2
320 smRepClosureTypeInt (GenericRep False _ _ Constr) = CONSTR
322 smRepClosureTypeInt (GenericRep False 1 0 Fun) = FUN_1_0
323 smRepClosureTypeInt (GenericRep False 0 1 Fun) = FUN_0_1
324 smRepClosureTypeInt (GenericRep False 2 0 Fun) = FUN_2_0
325 smRepClosureTypeInt (GenericRep False 1 1 Fun) = FUN_1_1
326 smRepClosureTypeInt (GenericRep False 0 2 Fun) = FUN_0_2
327 smRepClosureTypeInt (GenericRep False _ _ Fun) = FUN
329 smRepClosureTypeInt (GenericRep False 1 0 Thunk) = THUNK_1_0
330 smRepClosureTypeInt (GenericRep False 0 1 Thunk) = THUNK_0_1
331 smRepClosureTypeInt (GenericRep False 2 0 Thunk) = THUNK_2_0
332 smRepClosureTypeInt (GenericRep False 1 1 Thunk) = THUNK_1_1
333 smRepClosureTypeInt (GenericRep False 0 2 Thunk) = THUNK_0_2
334 smRepClosureTypeInt (GenericRep False _ _ Thunk) = THUNK
336 smRepClosureTypeInt (GenericRep False _ _ ThunkSelector) = THUNK_SELECTOR
338 smRepClosureTypeInt (GenericRep True _ _ Constr) = CONSTR_STATIC
339 smRepClosureTypeInt (GenericRep True _ _ ConstrNoCaf) = CONSTR_NOCAF_STATIC
340 smRepClosureTypeInt (GenericRep True _ _ Fun) = FUN_STATIC
341 smRepClosureTypeInt (GenericRep True _ _ Thunk) = THUNK_STATIC
343 smRepClosureTypeInt BlackHoleRep = BLACKHOLE
345 smRepClosureTypeInt rep = panic "smRepClosuretypeint"
348 -- We export these ones
349 rET_SMALL = (RET_SMALL :: StgHalfWord)
350 rET_BIG = (RET_BIG :: StgHalfWord)