2 % (c) The AQUA Project, Glasgow University, 1993-1998
6 module StixPrim ( primCode, amodeToStix, amodeToStix' ) where
8 #include "HsVersions.h"
14 import AbsCSyn hiding ( spRel )
15 import AbsCUtils ( getAmodeRep, mixedTypeLocn )
16 import SMRep ( fixedHdrSize )
17 import Literal ( Literal(..), word2IntLit )
18 import PrimOp ( PrimOp(..), CCall(..), CCallTarget(..) )
19 import PrimRep ( PrimRep(..) )
20 import UniqSupply ( returnUs, thenUs, getUniqueUs, UniqSM )
21 import Constants ( mIN_INTLIKE, mIN_CHARLIKE, uF_UPDATEE, bLOCK_SIZE,
22 rESERVED_STACK_WORDS )
23 import CLabel ( mkIntlikeClosureLabel, mkCharlikeClosureLabel,
24 mkMAP_FROZEN_infoLabel, mkForeignLabel )
25 import CallConv ( cCallConv )
32 The main honcho here is primCode, which handles the guts of COpStmts.
36 :: [CAddrMode] -- results
38 -> [CAddrMode] -- args
39 -> UniqSM StixTreeList
42 First, the dreaded @ccall@. We can't handle @casm@s.
44 Usually, this compiles to an assignment, but when the left-hand side
45 is empty, we just perform the call and ignore the result.
47 btw Why not let programmer use casm to provide assembly code instead
50 The (MP) integer operations are a true nightmare. Since we don't have
51 a convenient abstract way of allocating temporary variables on the (C)
52 stack, we use the space just below HpLim for the @MP_INT@ structures,
53 and modify our heap check accordingly.
56 -- NB: ordering of clauses somewhere driven by
57 -- the desire to getting sane patt-matching behavior
59 primCode [res] IntegerCmpOp args@[sa1,da1, sa2,da2]
60 = gmpCompare res (sa1,da1, sa2,da2)
62 primCode [res] IntegerCmpIntOp args@[sa1,da1,ai]
63 = gmpCompareInt res (sa1,da1,ai)
65 primCode [res] Integer2IntOp arg@[sa,da]
66 = gmpInteger2Int res (sa,da)
68 primCode [res] Integer2WordOp arg@[sa,da]
69 = gmpInteger2Word res (sa,da)
71 primCode [res] Int2AddrOp [arg]
72 = simpleCoercion AddrRep res arg
74 primCode [res] Addr2IntOp [arg]
75 = simpleCoercion IntRep res arg
77 primCode [res] Int2WordOp [arg]
78 = simpleCoercion IntRep{-WordRep?-} res arg
80 primCode [res] Word2IntOp [arg]
81 = simpleCoercion IntRep res arg
83 primCode [res] AddrToHValueOp [arg]
84 = simpleCoercion PtrRep res arg
88 primCode [res] SameMutableArrayOp args
90 compare = StPrim AddrEqOp (map amodeToStix args)
91 assign = StAssign IntRep (amodeToStix res) compare
93 returnUs (\xs -> assign : xs)
95 primCode res@[_] SameMutableByteArrayOp args
96 = primCode res SameMutableArrayOp args
98 primCode res@[_] SameMutVarOp args
99 = primCode res SameMutableArrayOp args
101 primCode res@[_] SameMVarOp args
102 = primCode res SameMutableArrayOp args
105 Freezing an array of pointers is a double assignment. We fix the
106 header of the ``new'' closure because the lhs is probably a better
107 addressing mode for the indirection (most likely, it's a VanillaReg).
111 primCode [lhs] UnsafeFreezeArrayOp [rhs]
113 lhs' = amodeToStix lhs
114 rhs' = amodeToStix rhs
115 header = StInd PtrRep lhs'
116 assign = StAssign PtrRep lhs' rhs'
117 freeze = StAssign PtrRep header mutArrPtrsFrozen_info
119 returnUs (\xs -> assign : freeze : xs)
121 primCode [lhs] UnsafeFreezeByteArrayOp [rhs]
122 = simpleCoercion PtrRep lhs rhs
125 Returning the size of (mutable) byte arrays is just
126 an indexing operation.
129 primCode [lhs] SizeofByteArrayOp [rhs]
131 lhs' = amodeToStix lhs
132 rhs' = amodeToStix rhs
133 sz = StIndex IntRep rhs' fixedHS
134 assign = StAssign IntRep lhs' (StInd IntRep sz)
136 returnUs (\xs -> assign : xs)
138 primCode [lhs] SizeofMutableByteArrayOp [rhs]
140 lhs' = amodeToStix lhs
141 rhs' = amodeToStix rhs
142 sz = StIndex IntRep rhs' fixedHS
143 assign = StAssign IntRep lhs' (StInd IntRep sz)
145 returnUs (\xs -> assign : xs)
149 Most other array primitives translate to simple indexing.
152 primCode lhs@[_] IndexArrayOp args
153 = primCode lhs ReadArrayOp args
155 primCode [lhs] ReadArrayOp [obj, ix]
157 lhs' = amodeToStix lhs
158 obj' = amodeToStix obj
160 base = StIndex IntRep obj' arrPtrsHS
161 assign = StAssign PtrRep lhs' (StInd PtrRep (StIndex PtrRep base ix'))
163 returnUs (\xs -> assign : xs)
165 primCode [] WriteArrayOp [obj, ix, v]
167 obj' = amodeToStix obj
170 base = StIndex IntRep obj' arrPtrsHS
171 assign = StAssign PtrRep (StInd PtrRep (StIndex PtrRep base ix')) v'
173 returnUs (\xs -> assign : xs)
175 primCode [] WriteForeignObjOp [obj, v]
177 obj' = amodeToStix obj
179 obj'' = StIndex AddrRep obj' (StInt 4711) -- fixedHS
180 assign = StAssign AddrRep (StInd AddrRep obj'') v'
182 returnUs (\xs -> assign : xs)
184 -- NB: indexing in "pk" units, *not* in bytes (WDP 95/09)
185 primCode ls IndexByteArrayOp_Char rs = primCode_ReadByteArrayOp Int8Rep ls rs
186 primCode ls IndexByteArrayOp_Int rs = primCode_ReadByteArrayOp IntRep ls rs
187 primCode ls IndexByteArrayOp_Word rs = primCode_ReadByteArrayOp WordRep ls rs
188 primCode ls IndexByteArrayOp_Addr rs = primCode_ReadByteArrayOp AddrRep ls rs
189 primCode ls IndexByteArrayOp_Float rs = primCode_ReadByteArrayOp FloatRep ls rs
190 primCode ls IndexByteArrayOp_Double rs = primCode_ReadByteArrayOp DoubleRep ls rs
191 primCode ls IndexByteArrayOp_StablePtr rs = primCode_ReadByteArrayOp StablePtrRep ls rs
192 primCode ls IndexByteArrayOp_Int64 rs = primCode_ReadByteArrayOp Int64Rep ls rs
193 primCode ls IndexByteArrayOp_Word64 rs = primCode_ReadByteArrayOp Word64Rep ls rs
195 primCode ls ReadByteArrayOp_Char rs = primCode_ReadByteArrayOp Int8Rep ls rs
196 primCode ls ReadByteArrayOp_Int rs = primCode_ReadByteArrayOp IntRep ls rs
197 primCode ls ReadByteArrayOp_Word rs = primCode_ReadByteArrayOp WordRep ls rs
198 primCode ls ReadByteArrayOp_Addr rs = primCode_ReadByteArrayOp AddrRep ls rs
199 primCode ls ReadByteArrayOp_Float rs = primCode_ReadByteArrayOp FloatRep ls rs
200 primCode ls ReadByteArrayOp_Double rs = primCode_ReadByteArrayOp DoubleRep ls rs
201 primCode ls ReadByteArrayOp_StablePtr rs = primCode_ReadByteArrayOp StablePtrRep ls rs
202 primCode ls ReadByteArrayOp_Int64 rs = primCode_ReadByteArrayOp Int64Rep ls rs
203 primCode ls ReadByteArrayOp_Word64 rs = primCode_ReadByteArrayOp Word64Rep ls rs
205 primCode ls ReadOffAddrOp_Char rs = primCode_IndexOffAddrOp Int8Rep ls rs
206 primCode ls ReadOffAddrOp_Int rs = primCode_IndexOffAddrOp IntRep ls rs
207 primCode ls ReadOffAddrOp_Word rs = primCode_IndexOffAddrOp WordRep ls rs
208 primCode ls ReadOffAddrOp_Addr rs = primCode_IndexOffAddrOp AddrRep ls rs
209 primCode ls ReadOffAddrOp_Float rs = primCode_IndexOffAddrOp FloatRep ls rs
210 primCode ls ReadOffAddrOp_Double rs = primCode_IndexOffAddrOp DoubleRep ls rs
211 primCode ls ReadOffAddrOp_StablePtr rs = primCode_IndexOffAddrOp StablePtrRep ls rs
212 primCode ls ReadOffAddrOp_Int64 rs = primCode_IndexOffAddrOp Int64Rep ls rs
213 primCode ls ReadOffAddrOp_Word64 rs = primCode_IndexOffAddrOp Word64Rep ls rs
215 primCode ls IndexOffAddrOp_Char rs = primCode_IndexOffAddrOp Int8Rep ls rs
216 primCode ls IndexOffAddrOp_Int rs = primCode_IndexOffAddrOp IntRep ls rs
217 primCode ls IndexOffAddrOp_Word rs = primCode_IndexOffAddrOp WordRep ls rs
218 primCode ls IndexOffAddrOp_Addr rs = primCode_IndexOffAddrOp AddrRep ls rs
219 primCode ls IndexOffAddrOp_Float rs = primCode_IndexOffAddrOp FloatRep ls rs
220 primCode ls IndexOffAddrOp_Double rs = primCode_IndexOffAddrOp DoubleRep ls rs
221 primCode ls IndexOffAddrOp_StablePtr rs = primCode_IndexOffAddrOp StablePtrRep ls rs
222 primCode ls IndexOffAddrOp_Int64 rs = primCode_IndexOffAddrOp Int64Rep ls rs
223 primCode ls IndexOffAddrOp_Word64 rs = primCode_IndexOffAddrOp Word64Rep ls rs
225 primCode ls IndexOffForeignObjOp_Char rs = primCode_IndexOffForeignObjOp Int8Rep ls rs
226 primCode ls IndexOffForeignObjOp_Int rs = primCode_IndexOffForeignObjOp IntRep ls rs
227 primCode ls IndexOffForeignObjOp_Word rs = primCode_IndexOffForeignObjOp WordRep ls rs
228 primCode ls IndexOffForeignObjOp_Addr rs = primCode_IndexOffForeignObjOp AddrRep ls rs
229 primCode ls IndexOffForeignObjOp_Float rs = primCode_IndexOffForeignObjOp FloatRep ls rs
230 primCode ls IndexOffForeignObjOp_Double rs = primCode_IndexOffForeignObjOp DoubleRep ls rs
231 primCode ls IndexOffForeignObjOp_StablePtr rs = primCode_IndexOffForeignObjOp StablePtrRep ls rs
232 primCode ls IndexOffForeignObjOp_Int64 rs = primCode_IndexOffForeignObjOp Int64Rep ls rs
233 primCode ls IndexOffForeignObjOp_Word64 rs = primCode_IndexOffForeignObjOp Word64Rep ls rs
235 primCode ls WriteOffAddrOp_Char rs = primCode_WriteOffAddrOp Int8Rep ls rs
236 primCode ls WriteOffAddrOp_Int rs = primCode_WriteOffAddrOp IntRep ls rs
237 primCode ls WriteOffAddrOp_Word rs = primCode_WriteOffAddrOp WordRep ls rs
238 primCode ls WriteOffAddrOp_Addr rs = primCode_WriteOffAddrOp AddrRep ls rs
239 primCode ls WriteOffAddrOp_Float rs = primCode_WriteOffAddrOp FloatRep ls rs
240 primCode ls WriteOffAddrOp_Double rs = primCode_WriteOffAddrOp DoubleRep ls rs
241 primCode ls WriteOffAddrOp_StablePtr rs = primCode_WriteOffAddrOp StablePtrRep ls rs
242 primCode ls WriteOffAddrOp_Int64 rs = primCode_WriteOffAddrOp Int64Rep ls rs
243 primCode ls WriteOffAddrOp_Word64 rs = primCode_WriteOffAddrOp Word64Rep ls rs
245 primCode ls WriteByteArrayOp_Char rs = primCode_WriteByteArrayOp Int8Rep ls rs
246 primCode ls WriteByteArrayOp_Int rs = primCode_WriteByteArrayOp IntRep ls rs
247 primCode ls WriteByteArrayOp_Word rs = primCode_WriteByteArrayOp WordRep ls rs
248 primCode ls WriteByteArrayOp_Addr rs = primCode_WriteByteArrayOp AddrRep ls rs
249 primCode ls WriteByteArrayOp_Float rs = primCode_WriteByteArrayOp FloatRep ls rs
250 primCode ls WriteByteArrayOp_Double rs = primCode_WriteByteArrayOp DoubleRep ls rs
251 primCode ls WriteByteArrayOp_StablePtr rs = primCode_WriteByteArrayOp StablePtrRep ls rs
252 primCode ls WriteByteArrayOp_Int64 rs = primCode_WriteByteArrayOp Int64Rep ls rs
253 primCode ls WriteByteArrayOp_Word64 rs = primCode_WriteByteArrayOp Word64Rep ls rs
257 ToDo: saving/restoring of volatile regs around ccalls.
259 JRS, 001113: always do the call of suspendThread and resumeThread as a ccall
260 rather than inheriting the calling convention of the thing which we're really
264 primCode lhs (CCallOp (CCall (StaticTarget fn) is_asm may_gc cconv)) rhs
265 | is_asm = error "ERROR: Native code generator can't handle casm"
266 | not may_gc = returnUs (\xs -> ccall : xs)
268 save_thread_state `thenUs` \ save ->
269 load_thread_state `thenUs` \ load ->
270 getUniqueUs `thenUs` \ uniq ->
272 id = StReg (StixTemp uniq IntRep)
274 suspend = StAssign IntRep id
275 (StCall SLIT("suspendThread") {-no:cconv-} cCallConv
277 resume = StCall SLIT("resumeThread") {-no:cconv-} cCallConv
280 returnUs (\xs -> save (suspend : ccall : resume : load xs))
283 args = map amodeCodeForCCall rhs
284 amodeCodeForCCall x =
285 let base = amodeToStix' x
287 case getAmodeRep x of
288 ArrayRep -> StIndex PtrRep base arrPtrsHS
289 ByteArrayRep -> StIndex IntRep base arrWordsHS
290 ForeignObjRep -> StInd PtrRep (StIndex PtrRep base fixedHS)
294 [] -> StCall fn cconv VoidRep args
296 let lhs' = amodeToStix lhs
297 pk = case getAmodeRep lhs of
299 DoubleRep -> DoubleRep
302 StAssign pk lhs' (StCall fn cconv pk args)
305 DataToTagOp won't work for 64-bit archs, as it is.
308 primCode [lhs] DataToTagOp [arg]
309 = let lhs' = amodeToStix lhs
310 arg' = amodeToStix arg
311 infoptr = StInd PtrRep arg'
312 word_32 = StInd WordRep (StIndex PtrRep infoptr (StInt (-1)))
313 masked_le32 = StPrim SrlOp [word_32, StInt 16]
314 masked_be32 = StPrim AndOp [word_32, StInt 65535]
315 #ifdef WORDS_BIGENDIAN
320 assign = StAssign IntRep lhs' masked
322 returnUs (\xs -> assign : xs)
325 MutVars are pretty simple.
326 #define writeMutVarzh(a,v) (P_)(((StgMutVar *)(a))->var)=(v)
329 primCode [] WriteMutVarOp [aa,vv]
330 = let aa_s = amodeToStix aa
331 vv_s = amodeToStix vv
332 var_field = StIndex PtrRep aa_s fixedHS
333 assign = StAssign PtrRep (StInd PtrRep var_field) vv_s
335 returnUs (\xs -> assign : xs)
337 primCode [rr] ReadMutVarOp [aa]
338 = let aa_s = amodeToStix aa
339 rr_s = amodeToStix rr
340 var_field = StIndex PtrRep aa_s fixedHS
341 assign = StAssign PtrRep rr_s (StInd PtrRep var_field)
343 returnUs (\xs -> assign : xs)
349 primCode [rr] ForeignObjToAddrOp [fo]
350 = let code = StAssign AddrRep (amodeToStix rr)
352 (StIndex PtrRep (amodeToStix fo) fixedHS))
354 returnUs (\xs -> code : xs)
356 primCode [] TouchOp [_] = returnUs id
359 Now the more mundane operations.
364 lhs' = map amodeToStix lhs
365 rhs' = map amodeToStix' rhs
366 pk = getAmodeRep (head lhs)
368 returnUs (\ xs -> simplePrim pk lhs' op rhs' : xs)
371 Helper fns for some array ops.
374 primCode_ReadByteArrayOp pk [lhs] [obj, ix]
376 lhs' = amodeToStix lhs
377 obj' = amodeToStix obj
379 base = StIndex IntRep obj' arrWordsHS
380 assign = StAssign pk lhs' (StInd pk (StIndex pk base ix'))
382 returnUs (\xs -> assign : xs)
385 primCode_IndexOffAddrOp pk [lhs] [obj, ix]
387 lhs' = amodeToStix lhs
388 obj' = amodeToStix obj
390 assign = StAssign pk lhs' (StInd pk (StIndex pk obj' ix'))
392 returnUs (\xs -> assign : xs)
395 primCode_IndexOffForeignObjOp pk [lhs] [obj, ix]
397 lhs' = amodeToStix lhs
398 obj' = amodeToStix obj
400 obj'' = StIndex AddrRep obj' fixedHS
401 assign = StAssign pk lhs' (StInd pk (StIndex pk obj'' ix'))
403 returnUs (\xs -> assign : xs)
406 primCode_WriteOffAddrOp pk [] [obj, ix, v]
408 obj' = amodeToStix obj
411 assign = StAssign pk (StInd pk (StIndex pk obj' ix')) v'
413 returnUs (\xs -> assign : xs)
416 primCode_WriteByteArrayOp pk [] [obj, ix, v]
418 obj' = amodeToStix obj
421 base = StIndex IntRep obj' arrWordsHS
422 assign = StAssign pk (StInd pk (StIndex pk base ix')) v'
424 returnUs (\xs -> assign : xs)
433 -> UniqSM StixTreeList
435 simpleCoercion pk lhs rhs
436 = returnUs (\xs -> StAssign pk (amodeToStix lhs) (amodeToStix rhs) : xs)
439 Here we try to rewrite primitives into a form the code generator can
440 understand. Any primitives not handled here must be handled at the
441 level of the specific code generator.
445 :: PrimRep -- Rep of first destination
446 -> [StixTree] -- Destinations
452 Now look for something more conventional.
455 simplePrim pk [lhs] op rest = StAssign pk lhs (StPrim op rest)
456 simplePrim pk as op bs = simplePrim_error op
459 = error ("ERROR: primitive operation `"++show op++"'cannot be handled\nby the native-code generator. Workaround: use -fvia-C.\n(Perhaps you should report it as a GHC bug, also.)\n")
462 %---------------------------------------------------------------------
464 Here we generate the Stix code for CAddrModes.
466 When a character is fetched from a mixed type location, we have to do
467 an extra cast. This is reflected in amodeCode', which is for rhs
468 amodes that might possibly need the extra cast.
471 amodeToStix, amodeToStix' :: CAddrMode -> StixTree
473 amodeToStix'{-'-} am@(CVal rr CharRep)
474 | mixedTypeLocn am = StPrim ChrOp [amodeToStix am]
475 | otherwise = amodeToStix am
477 amodeToStix' am = amodeToStix am
480 amodeToStix am@(CVal rr CharRep)
482 = StInd IntRep (amodeToStix (CAddr rr))
484 amodeToStix (CVal rr pk) = StInd pk (amodeToStix (CAddr rr))
486 amodeToStix (CAddr (SpRel off))
487 = StIndex PtrRep stgSp (StInt (toInteger (iBox off)))
489 amodeToStix (CAddr (HpRel off))
490 = StIndex IntRep stgHp (StInt (toInteger (- (iBox off))))
492 amodeToStix (CAddr (NodeRel off))
493 = StIndex IntRep stgNode (StInt (toInteger (iBox off)))
495 amodeToStix (CAddr (CIndex base off pk))
496 = StIndex pk (amodeToStix base) (amodeToStix off)
498 amodeToStix (CReg magic) = StReg (StixMagicId magic)
499 amodeToStix (CTemp uniq pk) = StReg (StixTemp uniq pk)
501 amodeToStix (CLbl lbl _) = StCLbl lbl
503 -- For CharLike and IntLike, we attempt some trivial constant-folding here.
505 amodeToStix (CCharLike (CLit (MachChar c)))
506 = StIndex Int8Rep cHARLIKE_closure (StInt (toInteger off))
508 off = charLikeSize * (c - mIN_CHARLIKE)
510 amodeToStix (CCharLike x)
513 amodeToStix (CIntLike (CLit (MachInt i)))
514 = StIndex Int8Rep iNTLIKE_closure (StInt (toInteger off))
516 off = intLikeSize * (fromInteger (i - mIN_INTLIKE))
518 amodeToStix (CIntLike x)
521 amodeToStix (CLit core)
523 MachChar c -> StInt (toInteger c)
524 MachStr s -> StString s
525 MachAddr a -> StInt a
527 MachWord w -> case word2IntLit core of MachInt iw -> StInt iw
528 MachLitLit s _ -> litLitErr
529 MachLabel l -> StCLbl (mkForeignLabel l False{-ToDo: dynamic-})
530 MachFloat d -> StFloat d
531 MachDouble d -> StDouble d
532 _ -> panic "amodeToStix:core literal"
534 amodeToStix (CMacroExpr _ macro [arg])
536 ENTRY_CODE -> amodeToStix arg
537 ARG_TAG -> amodeToStix arg -- just an integer no. of words
539 #ifdef WORDS_BIGENDIAN
541 [StInd WordRep (StIndex PtrRep (amodeToStix arg)
542 (StInt (toInteger (-1)))),
546 [StInd WordRep (StIndex PtrRep (amodeToStix arg)
547 (StInt (toInteger (-1)))),
551 -> StInd PtrRep (StIndex PtrRep (amodeToStix arg)
552 (StInt (toInteger uF_UPDATEE)))
555 panic "native code generator can't compile lit-lits, use -fvia-C"
558 Sizes of the CharLike and IntLike closures that are arranged as arrays
559 in the data segment. (These are in bytes.)
562 -- The INTLIKE base pointer
564 iNTLIKE_closure :: StixTree
565 iNTLIKE_closure = StCLbl mkIntlikeClosureLabel
569 cHARLIKE_closure :: StixTree
570 cHARLIKE_closure = StCLbl mkCharlikeClosureLabel
572 mutArrPtrsFrozen_info = StCLbl mkMAP_FROZEN_infoLabel
574 -- these are the sizes of charLike and intLike closures, in _bytes_.
575 charLikeSize = (fixedHdrSize + 1) * (fromInteger (sizeOf PtrRep))
576 intLikeSize = (fixedHdrSize + 1) * (fromInteger (sizeOf PtrRep))
582 = getUniqueUs `thenUs` \tso_uq ->
583 let tso = StReg (StixTemp tso_uq ThreadIdRep) in
585 StAssign ThreadIdRep tso stgCurrentTSO :
587 (StInd PtrRep (StPrim IntAddOp
588 [tso, StInt (toInteger (TSO_SP*BYTES_PER_WORD))]))
591 (StInd PtrRep (StPrim IntAddOp
592 [tso, StInt (toInteger (TSO_SU*BYTES_PER_WORD))]))
595 (StInd PtrRep (StPrim IntAddOp
597 StInt (toInteger (BDESCR_FREE * BYTES_PER_WORD))]))
598 (StPrim IntAddOp [stgHp, StInt (toInteger (1 * BYTES_PER_WORD))]) :
603 = getUniqueUs `thenUs` \tso_uq ->
604 let tso = StReg (StixTemp tso_uq ThreadIdRep) in
606 StAssign ThreadIdRep tso stgCurrentTSO :
607 StAssign PtrRep stgSp
608 (StInd PtrRep (StPrim IntAddOp
609 [tso, StInt (toInteger (TSO_SP*BYTES_PER_WORD))])) :
610 StAssign PtrRep stgSu
611 (StInd PtrRep (StPrim IntAddOp
612 [tso, StInt (toInteger (TSO_SU*BYTES_PER_WORD))])) :
613 StAssign PtrRep stgSpLim
614 (StPrim IntAddOp [tso,
615 StInt (toInteger ((TSO_STACK + rESERVED_STACK_WORDS)
616 *BYTES_PER_WORD))]) :
617 StAssign PtrRep stgHp
619 StInd PtrRep (StPrim IntAddOp
621 StInt (toInteger (BDESCR_FREE * BYTES_PER_WORD))]),
622 StInt (toInteger (1 * BYTES_PER_WORD))
624 StAssign PtrRep stgHpLim
626 StInd PtrRep (StPrim IntAddOp
628 StInt (toInteger (BDESCR_START * BYTES_PER_WORD))]),
629 StInt (toInteger (bLOCK_SIZE - (1 * BYTES_PER_WORD)))