1 /*------------------------------------------------------------------------
3 SDCCralloc.c - source file for register allocation. (8051) specific
5 Written By - Sandeep Dutta . sandeep.dutta@usa.net (1998)
7 This program is free software; you can redistribute it and/or modify it
8 under the terms of the GNU General Public License as published by the
9 Free Software Foundation; either version 2, or (at your option) any
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
21 In other words, you are welcome to use, share and improve this program.
22 You are forbidden to forbid anyone else to use, share and improve
23 what you give them. Help stamp out software-hoarding!
24 -------------------------------------------------------------------------*/
30 /*-----------------------------------------------------------------*/
31 /* At this point we start getting processor specific although */
32 /* some routines are non-processor specific & can be reused when */
33 /* targetting other processors. The decision for this will have */
34 /* to be made on a routine by routine basis */
35 /* routines used to pack registers are most definitely not reusable */
36 /* since the pack the registers depending strictly on the MCU */
37 /*-----------------------------------------------------------------*/
39 extern void gen51Code (iCode *);
48 bitVect *totRegAssigned; /* final set of LRs that got into registers */
51 bitVect *funcrUsed; /* registers used in a function */
54 bitVect *allBitregs; /* all bit registers */
58 /* Shared with gen.c */
59 int mcs51_ptrRegReq; /* one byte pointer register required */
65 {REG_GPR, R2_IDX, REG_GPR, "r2", "ar2", "0", 2, 1},
66 {REG_GPR, R3_IDX, REG_GPR, "r3", "ar3", "0", 3, 1},
67 {REG_GPR, R4_IDX, REG_GPR, "r4", "ar4", "0", 4, 1},
68 {REG_GPR, R5_IDX, REG_GPR, "r5", "ar5", "0", 5, 1},
69 {REG_GPR, R6_IDX, REG_GPR, "r6", "ar6", "0", 6, 1},
70 {REG_GPR, R7_IDX, REG_GPR, "r7", "ar7", "0", 7, 1},
71 {REG_PTR, R0_IDX, REG_PTR, "r0", "ar0", "0", 0, 1},
72 {REG_PTR, R1_IDX, REG_PTR, "r1", "ar1", "0", 1, 1},
73 {REG_BIT, B0_IDX, REG_BIT, "b0", "b0", "bits", 0, 1},
74 {REG_BIT, B1_IDX, REG_BIT, "b1", "b1", "bits", 1, 1},
75 {REG_BIT, B2_IDX, REG_BIT, "b2", "b2", "bits", 2, 1},
76 {REG_BIT, B3_IDX, REG_BIT, "b3", "b3", "bits", 3, 1},
77 {REG_BIT, B4_IDX, REG_BIT, "b4", "b4", "bits", 4, 1},
78 {REG_BIT, B5_IDX, REG_BIT, "b5", "b5", "bits", 5, 1},
79 {REG_BIT, B6_IDX, REG_BIT, "b6", "b6", "bits", 6, 1},
80 {REG_BIT, B7_IDX, REG_BIT, "b7", "b7", "bits", 7, 1},
81 {REG_GPR, X8_IDX, REG_GPR, "x8", "x8", "xreg", 0, 1},
82 {REG_GPR, X9_IDX, REG_GPR, "x9", "x9", "xreg", 1, 1},
83 {REG_GPR, X10_IDX, REG_GPR, "x10", "x10", "xreg", 2, 1},
84 {REG_GPR, X11_IDX, REG_GPR, "x11", "x11", "xreg", 3, 1},
85 {REG_GPR, X12_IDX, REG_GPR, "x12", "x12", "xreg", 4, 1},
86 {REG_CND, CND_IDX, REG_CND, "C", "psw", "0xd0", 0, 1},
87 {0, DPL_IDX, 0, "dpl", "dpl", "0x82", 0, 0},
88 {0, DPH_IDX, 0, "dph", "dph", "0x83", 0, 0},
89 {0, B_IDX, 0, "b", "b", "0xf0", 0, 0},
90 {0, A_IDX, 0, "a", "acc", "0xe0", 0, 0},
93 static void spillThis (symbol *);
94 static void freeAllRegs ();
96 /*-----------------------------------------------------------------*/
97 /* allocReg - allocates register of given type */
98 /*-----------------------------------------------------------------*/
100 allocReg (short type)
104 for (i = 0; i < mcs51_nRegs; i++)
107 /* if type is given as 0 then any
108 free register will do */
112 regs8051[i].isFree = 0;
115 bitVectSetBit (currFunc->regsUsed, i);
118 /* other wise look for specific type
120 if (regs8051[i].isFree &&
121 regs8051[i].type == type)
123 regs8051[i].isFree = 0;
126 bitVectSetBit (currFunc->regsUsed, i);
133 /*-----------------------------------------------------------------*/
134 /* allocThisReg - allocates a particular register (if free) */
135 /*-----------------------------------------------------------------*/
137 allocThisReg (regs * reg)
144 currFunc->regsUsed = bitVectSetBit (currFunc->regsUsed, reg->rIdx);
150 /*-----------------------------------------------------------------*/
151 /* mcs51_regWithIdx - returns pointer to register with index number*/
152 /*-----------------------------------------------------------------*/
154 mcs51_regWithIdx (int idx)
158 for (i = 0; i < sizeof(regs8051)/sizeof(regs); i++)
159 if (regs8051[i].rIdx == idx)
162 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
163 "regWithIdx not found");
167 /*-----------------------------------------------------------------*/
168 /* freeReg - frees a register */
169 /*-----------------------------------------------------------------*/
175 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
176 "freeReg - Freeing NULL register");
184 /*-----------------------------------------------------------------*/
185 /* nFreeRegs - returns number of free registers */
186 /*-----------------------------------------------------------------*/
193 for (i = 0; i < mcs51_nRegs; i++)
194 if (regs8051[i].isFree && regs8051[i].type == type)
199 /*-----------------------------------------------------------------*/
200 /* nfreeRegsType - free registers with type */
201 /*-----------------------------------------------------------------*/
203 nfreeRegsType (int type)
208 if ((nfr = nFreeRegs (type)) == 0)
209 return nFreeRegs (REG_GPR);
212 return nFreeRegs (type);
215 /*-----------------------------------------------------------------*/
216 /* useReg - marks a register as used */
217 /*-----------------------------------------------------------------*/
224 /*-----------------------------------------------------------------*/
225 /* computeSpillable - given a point find the spillable live ranges */
226 /*-----------------------------------------------------------------*/
228 computeSpillable (iCode * ic)
232 /* spillable live ranges are those that are live at this
233 point . the following categories need to be subtracted
235 a) - those that are already spilt
236 b) - if being used by this one
237 c) - defined by this one */
239 spillable = bitVectCopy (ic->rlive);
241 bitVectCplAnd (spillable, _G.spiltSet); /* those already spilt */
243 bitVectCplAnd (spillable, ic->uses); /* used in this one */
244 bitVectUnSetBit (spillable, ic->defKey);
245 spillable = bitVectIntersect (spillable, _G.regAssigned);
250 /*-----------------------------------------------------------------*/
251 /* bitType - will return 1 if the symbol has type REG_BIT */
252 /*-----------------------------------------------------------------*/
254 bitType (symbol * sym, eBBlock * ebp, iCode * ic)
256 return (sym->regType == REG_BIT ? 1 : 0);
259 /*-----------------------------------------------------------------*/
260 /* noSpilLoc - return true if a variable has no spil location */
261 /*-----------------------------------------------------------------*/
263 noSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
265 return (sym->usl.spillLoc ? 0 : 1);
268 /*-----------------------------------------------------------------*/
269 /* hasSpilLoc - will return 1 if the symbol has spil location */
270 /*-----------------------------------------------------------------*/
272 hasSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
274 return (sym->usl.spillLoc ? 1 : 0);
277 /*-----------------------------------------------------------------*/
278 /* directSpilLoc - will return 1 if the spillocation is in direct */
279 /*-----------------------------------------------------------------*/
281 directSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
283 if (sym->usl.spillLoc &&
284 (IN_DIRSPACE (SPEC_OCLS (sym->usl.spillLoc->etype))))
290 /*-----------------------------------------------------------------*/
291 /* hasSpilLocnoUptr - will return 1 if the symbol has spil location */
292 /* but is not used as a pointer */
293 /*-----------------------------------------------------------------*/
295 hasSpilLocnoUptr (symbol * sym, eBBlock * ebp, iCode * ic)
297 return ((sym->usl.spillLoc && !sym->uptr) ? 1 : 0);
300 /*-----------------------------------------------------------------*/
301 /* rematable - will return 1 if the remat flag is set */
302 /*-----------------------------------------------------------------*/
304 rematable (symbol * sym, eBBlock * ebp, iCode * ic)
309 /*-----------------------------------------------------------------*/
310 /* notUsedInRemaining - not used or defined in remain of the block */
311 /*-----------------------------------------------------------------*/
313 notUsedInRemaining (symbol * sym, eBBlock * ebp, iCode * ic)
315 return ((usedInRemaining (operandFromSymbol (sym), ic) ? 0 : 1) &&
316 allDefsOutOfRange (sym->defs, ebp->fSeq, ebp->lSeq));
319 /*-----------------------------------------------------------------*/
320 /* allLRs - return true for all */
321 /*-----------------------------------------------------------------*/
323 allLRs (symbol * sym, eBBlock * ebp, iCode * ic)
328 /*-----------------------------------------------------------------*/
329 /* liveRangesWith - applies function to a given set of live range */
330 /*-----------------------------------------------------------------*/
332 liveRangesWith (bitVect * lrs, int (func) (symbol *, eBBlock *, iCode *),
333 eBBlock * ebp, iCode * ic)
338 if (!lrs || !lrs->size)
341 for (i = 1; i < lrs->size; i++)
344 if (!bitVectBitValue (lrs, i))
347 /* if we don't find it in the live range
348 hash table we are in serious trouble */
349 if (!(sym = hTabItemWithKey (liveRanges, i)))
351 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
352 "liveRangesWith could not find liveRange");
356 if (func (sym, ebp, ic) && bitVectBitValue (_G.regAssigned, sym->key))
357 addSetHead (&rset, sym);
364 /*-----------------------------------------------------------------*/
365 /* leastUsedLR - given a set determines which is the least used */
366 /*-----------------------------------------------------------------*/
368 leastUsedLR (set * sset)
370 symbol *sym = NULL, *lsym = NULL;
372 sym = lsym = setFirstItem (sset);
377 for (; lsym; lsym = setNextItem (sset))
380 /* if usage is the same then prefer
381 to spill the smaller of the two */
382 if (lsym->used == sym->used)
383 if (getSize (lsym->type) < getSize (sym->type))
387 if (lsym->used < sym->used)
392 setToNull ((void *) &sset);
397 /*-----------------------------------------------------------------*/
398 /* noOverLap - will iterate through the list looking for over lap */
399 /*-----------------------------------------------------------------*/
401 noOverLap (set * itmpStack, symbol * fsym)
405 for (sym = setFirstItem (itmpStack); sym;
406 sym = setNextItem (itmpStack))
408 if (bitVectBitValue(sym->clashes,fsym->key)) return 0;
413 /*-----------------------------------------------------------------*/
414 /* isFree - will return 1 if the a free spil location is found */
415 /*-----------------------------------------------------------------*/
420 V_ARG (symbol **, sloc);
421 V_ARG (symbol *, fsym);
423 /* if already found */
427 /* if it is free && and the itmp assigned to
428 this does not have any overlapping live ranges
429 with the one currently being assigned and
430 the size can be accomodated */
432 noOverLap (sym->usl.itmpStack, fsym) &&
433 getSize (sym->type) >= getSize (fsym->type))
442 /*-----------------------------------------------------------------*/
443 /* spillLRWithPtrReg :- will spil those live ranges which use PTR */
444 /*-----------------------------------------------------------------*/
446 spillLRWithPtrReg (symbol * forSym)
452 if (!_G.regAssigned ||
453 bitVectIsZero (_G.regAssigned))
456 r0 = mcs51_regWithIdx (R0_IDX);
457 r1 = mcs51_regWithIdx (R1_IDX);
459 /* for all live ranges */
460 for (lrsym = hTabFirstItem (liveRanges, &k); lrsym;
461 lrsym = hTabNextItem (liveRanges, &k))
465 /* if no registers assigned to it or spilt */
466 /* if it does not overlap this then
467 no need to spill it */
469 if (lrsym->isspilt || !lrsym->nRegs ||
470 (lrsym->liveTo < forSym->liveFrom))
473 /* go thru the registers : if it is either
474 r0 or r1 then spill it */
475 for (j = 0; j < lrsym->nRegs; j++)
476 if (lrsym->regs[j] == r0 ||
477 lrsym->regs[j] == r1)
486 /*-----------------------------------------------------------------*/
487 /* createStackSpil - create a location on the stack to spil */
488 /*-----------------------------------------------------------------*/
490 createStackSpil (symbol * sym)
493 int useXstack, model;
497 /* first go try and find a free one that is already
498 existing on the stack */
499 if (applyToSet (_G.stackSpil, isFree, &sloc, sym))
501 /* found a free one : just update & return */
502 sym->usl.spillLoc = sloc;
505 addSetHead (&sloc->usl.itmpStack, sym);
509 /* could not then have to create one , this is the hard part
510 we need to allocate this on the stack : this is really a
511 hack!! but cannot think of anything better at this time */
513 if (SNPRINTF (slocBuffer, sizeof(slocBuffer),
514 "sloc%d", _G.slocNum++) >= sizeof (slocBuffer))
516 fprintf (stderr, "***Internal error: slocBuffer overflowed: %s:%d\n",
521 sloc = newiTemp (slocBuffer);
523 /* set the type to the spilling symbol */
524 sloc->type = copyLinkChain (sym->type);
525 sloc->etype = getSpec (sloc->type);
526 if (!IS_BIT (sloc->etype))
528 SPEC_SCLS (sloc->etype) = S_DATA;
530 SPEC_EXTR (sloc->etype) = 0;
531 SPEC_STAT (sloc->etype) = 0;
532 SPEC_VOLATILE(sloc->etype) = 0;
533 SPEC_ABSA(sloc->etype) = 0;
535 /* we don't allow it to be allocated`
536 onto the external stack since : so we
537 temporarily turn it off ; we also
538 turn off memory model to prevent
539 the spil from going to the external storage
542 useXstack = options.useXstack;
543 model = options.model;
544 /* noOverlay = options.noOverlay; */
545 /* options.noOverlay = 1; */
546 options.model = options.useXstack = 0;
550 options.useXstack = useXstack;
551 options.model = model;
552 /* options.noOverlay = noOverlay; */
553 sloc->isref = 1; /* to prevent compiler warning */
555 /* if it is on the stack then update the stack */
556 if (IN_STACK (sloc->etype))
558 currFunc->stack += getSize (sloc->type);
559 _G.stackExtend += getSize (sloc->type);
562 _G.dataExtend += getSize (sloc->type);
564 /* add it to the _G.stackSpil set */
565 addSetHead (&_G.stackSpil, sloc);
566 sym->usl.spillLoc = sloc;
569 /* add it to the set of itempStack set
570 of the spill location */
571 addSetHead (&sloc->usl.itmpStack, sym);
575 /*-----------------------------------------------------------------*/
576 /* isSpiltOnStack - returns true if the spil location is on stack */
577 /*-----------------------------------------------------------------*/
579 isSpiltOnStack (symbol * sym)
589 /* if (sym->_G.stackSpil) */
592 if (!sym->usl.spillLoc)
595 etype = getSpec (sym->usl.spillLoc->type);
596 if (IN_STACK (etype))
602 /*-----------------------------------------------------------------*/
603 /* spillThis - spils a specific operand */
604 /*-----------------------------------------------------------------*/
606 spillThis (symbol * sym)
609 /* if this is rematerializable or has a spillLocation
610 we are okay, else we need to create a spillLocation
612 if (!(sym->remat || sym->usl.spillLoc))
613 createStackSpil (sym);
615 /* mark it has spilt & put it in the spilt set */
616 sym->isspilt = sym->spillA = 1;
617 _G.spiltSet = bitVectSetBit (_G.spiltSet, sym->key);
619 bitVectUnSetBit (_G.regAssigned, sym->key);
620 bitVectUnSetBit (_G.totRegAssigned, sym->key);
622 for (i = 0; i < sym->nRegs; i++)
626 freeReg (sym->regs[i]);
630 /* if spilt on stack then free up r0 & r1
631 if they could have been assigned to some
633 if (!mcs51_ptrRegReq && isSpiltOnStack (sym))
636 spillLRWithPtrReg (sym);
639 if (sym->usl.spillLoc && !sym->remat)
640 sym->usl.spillLoc->allocreq++;
644 /*-----------------------------------------------------------------*/
645 /* selectSpil - select a iTemp to spil : rather a simple procedure */
646 /*-----------------------------------------------------------------*/
648 selectSpil (iCode * ic, eBBlock * ebp, symbol * forSym)
650 bitVect *lrcs = NULL;
654 /* get the spillable live ranges */
655 lrcs = computeSpillable (ic);
657 /* remove incompatible registers */
658 if ((forSym->regType == REG_PTR) || (forSym->regType == REG_GPR))
660 selectS = liveRangesWith (lrcs, bitType, ebp, ic);
662 for (sym = setFirstItem (selectS); sym; sym = setNextItem (selectS))
664 bitVectUnSetBit (lrcs, sym->key);
668 /* get all live ranges that are rematerializable */
669 if ((selectS = liveRangesWith (lrcs, rematable, ebp, ic)))
671 /* return the least used of these */
672 return leastUsedLR (selectS);
675 /* get live ranges with spillLocations in direct space */
676 if ((selectS = liveRangesWith (lrcs, directSpilLoc, ebp, ic)))
678 sym = leastUsedLR (selectS);
679 strncpyz (sym->rname,
680 sym->usl.spillLoc->rname[0] ?
681 sym->usl.spillLoc->rname : sym->usl.spillLoc->name,
684 /* mark it as allocation required */
685 sym->usl.spillLoc->allocreq++;
689 /* if the symbol is local to the block then */
690 if (forSym->liveTo < ebp->lSeq)
692 /* check if there are any live ranges allocated
693 to registers that are not used in this block */
694 if (!_G.blockSpil && (selectS = liveRangesWith (lrcs, notUsedInBlock, ebp, ic)))
696 sym = leastUsedLR (selectS);
697 /* if this is not rematerializable */
706 /* check if there are any live ranges that not
707 used in the remainder of the block */
709 !isiCodeInFunctionCall (ic) &&
710 (selectS = liveRangesWith (lrcs, notUsedInRemaining, ebp, ic)))
712 sym = leastUsedLR (selectS);
725 /* find live ranges with spillocation && not used as pointers */
726 if ((selectS = liveRangesWith (lrcs, hasSpilLocnoUptr, ebp, ic)))
728 sym = leastUsedLR (selectS);
729 /* mark this as allocation required */
730 sym->usl.spillLoc->allocreq++;
734 /* find live ranges with spillocation */
735 if ((selectS = liveRangesWith (lrcs, hasSpilLoc, ebp, ic)))
737 sym = leastUsedLR (selectS);
738 sym->usl.spillLoc->allocreq++;
742 /* couldn't find then we need to create a spil
743 location on the stack , for which one? the least
745 if ((selectS = liveRangesWith (lrcs, noSpilLoc, ebp, ic)))
747 /* return a created spil location */
748 sym = createStackSpil (leastUsedLR (selectS));
749 sym->usl.spillLoc->allocreq++;
753 /* this is an extreme situation we will spill
754 this one : happens very rarely but it does happen */
760 /*-----------------------------------------------------------------*/
761 /* spilSomething - spil some variable & mark registers as free */
762 /*-----------------------------------------------------------------*/
764 spilSomething (iCode * ic, eBBlock * ebp, symbol * forSym)
769 /* get something we can spil */
770 ssym = selectSpil (ic, ebp, forSym);
772 /* mark it as spilt */
773 ssym->isspilt = ssym->spillA = 1;
774 _G.spiltSet = bitVectSetBit (_G.spiltSet, ssym->key);
776 /* mark it as not register assigned &
777 take it away from the set */
778 bitVectUnSetBit (_G.regAssigned, ssym->key);
779 bitVectUnSetBit (_G.totRegAssigned, ssym->key);
781 /* mark the registers as free */
782 for (i = 0; i < ssym->nRegs; i++)
784 freeReg (ssym->regs[i]);
786 /* if spilt on stack then free up r0 & r1
787 if they could have been assigned to as gprs */
788 if (!mcs51_ptrRegReq && isSpiltOnStack (ssym))
791 spillLRWithPtrReg (ssym);
794 /* if this was a block level spil then insert push & pop
795 at the start & end of block respectively */
798 iCode *nic = newiCode (IPUSH, operandFromSymbol (ssym), NULL);
799 /* add push to the start of the block */
800 addiCodeToeBBlock (ebp, nic, (ebp->sch->op == LABEL ?
801 ebp->sch->next : ebp->sch));
802 nic = newiCode (IPOP, operandFromSymbol (ssym), NULL);
803 /* add pop to the end of the block */
804 addiCodeToeBBlock (ebp, nic, NULL);
807 /* if spilt because not used in the remainder of the
808 block then add a push before this instruction and
809 a pop at the end of the block */
810 if (ssym->remainSpil)
813 iCode *nic = newiCode (IPUSH, operandFromSymbol (ssym), NULL);
814 /* add push just before this instruction */
815 addiCodeToeBBlock (ebp, nic, ic);
817 nic = newiCode (IPOP, operandFromSymbol (ssym), NULL);
818 /* add pop to the end of the block */
819 addiCodeToeBBlock (ebp, nic, NULL);
828 /*-----------------------------------------------------------------*/
829 /* getRegPtr - will try for PTR if not a GPR type if not spil */
830 /*-----------------------------------------------------------------*/
832 getRegPtr (iCode * ic, eBBlock * ebp, symbol * sym)
838 /* try for a ptr type */
839 if ((reg = allocReg (REG_PTR)))
842 /* try for gpr type */
843 if ((reg = allocReg (REG_GPR)))
846 /* we have to spil */
847 if (!spilSomething (ic, ebp, sym))
850 /* make sure partially assigned registers aren't reused */
851 for (j=0; j<=sym->nRegs; j++)
853 sym->regs[j]->isFree = 0;
855 /* this looks like an infinite loop but
856 in really selectSpil will abort */
860 /*-----------------------------------------------------------------*/
861 /* getRegGpr - will try for GPR if not spil */
862 /*-----------------------------------------------------------------*/
864 getRegGpr (iCode * ic, eBBlock * ebp, symbol * sym)
870 /* try for gpr type */
871 if ((reg = allocReg (REG_GPR)))
874 if (!mcs51_ptrRegReq)
875 if ((reg = allocReg (REG_PTR)))
878 /* we have to spil */
879 if (!spilSomething (ic, ebp, sym))
882 /* make sure partially assigned registers aren't reused */
883 for (j=0; j<=sym->nRegs; j++)
885 sym->regs[j]->isFree = 0;
887 /* this looks like an infinite loop but
888 in really selectSpil will abort */
892 /*-----------------------------------------------------------------*/
893 /* getRegBit - will try for Bit if not spill this */
894 /*-----------------------------------------------------------------*/
895 static regs *getRegBit (symbol * sym)
899 /* try for a bit type */
900 if ((reg = allocReg (REG_BIT)))
907 /*-----------------------------------------------------------------*/
908 /* getRegPtrNoSpil - get it cannot be spilt */
909 /*-----------------------------------------------------------------*/
910 static regs *getRegPtrNoSpil()
914 /* try for a ptr type */
915 if ((reg = allocReg (REG_PTR)))
918 /* try for gpr type */
919 if ((reg = allocReg (REG_GPR)))
924 /* just to make the compiler happy */
928 /*-----------------------------------------------------------------*/
929 /* getRegGprNoSpil - get it cannot be spilt */
930 /*-----------------------------------------------------------------*/
931 static regs *getRegGprNoSpil()
935 if ((reg = allocReg (REG_GPR)))
938 if (!mcs51_ptrRegReq)
939 if ((reg = allocReg (REG_PTR)))
944 /* just to make the compiler happy */
948 /*-----------------------------------------------------------------*/
949 /* getRegBitNoSpil - get it cannot be spilt */
950 /*-----------------------------------------------------------------*/
951 static regs *getRegBitNoSpil()
955 /* try for a ptr type */
956 if ((reg = allocReg (REG_BIT)))
959 /* try for gpr type */
960 if ((reg = allocReg (REG_GPR)))
965 /* just to make the compiler happy */
969 /*-----------------------------------------------------------------*/
970 /* symHasReg - symbol has a given register */
971 /*-----------------------------------------------------------------*/
973 symHasReg (symbol * sym, regs * reg)
977 for (i = 0; i < sym->nRegs; i++)
978 if (sym->regs[i] == reg)
984 /*-----------------------------------------------------------------*/
985 /* updateRegUsage - update the registers in use at the start of */
987 /*-----------------------------------------------------------------*/
989 updateRegUsage (iCode * ic)
993 for (reg=0; reg<mcs51_nRegs; reg++)
995 if (regs8051[reg].isFree)
997 ic->riu &= ~(1<<regs8051[reg].offset);
1001 ic->riu |= (1<<regs8051[reg].offset);
1002 BitBankUsed |= (reg >= 8);
1007 /*-----------------------------------------------------------------*/
1008 /* deassignLRs - check the live to and if they have registers & are */
1009 /* not spilt then free up the registers */
1010 /*-----------------------------------------------------------------*/
1012 deassignLRs (iCode * ic, eBBlock * ebp)
1018 for (sym = hTabFirstItem (liveRanges, &k); sym;
1019 sym = hTabNextItem (liveRanges, &k))
1022 symbol *psym = NULL;
1023 /* if it does not end here */
1024 if (sym->liveTo > ic->seq)
1027 /* if it was spilt on stack then we can
1028 mark the stack spil location as free */
1033 sym->usl.spillLoc->isFree = 1;
1039 if (!bitVectBitValue (_G.regAssigned, sym->key))
1042 /* special case check if this is an IFX &
1043 the privious one was a pop and the
1044 previous one was not spilt then keep track
1046 if (ic->op == IFX && ic->prev &&
1047 ic->prev->op == IPOP &&
1048 !ic->prev->parmPush &&
1049 !OP_SYMBOL (IC_LEFT (ic->prev))->isspilt)
1050 psym = OP_SYMBOL (IC_LEFT (ic->prev));
1056 bitVectUnSetBit (_G.regAssigned, sym->key);
1058 /* if the result of this one needs registers
1059 and does not have it then assign it right
1061 if (IC_RESULT (ic) &&
1062 !(SKIP_IC2 (ic) || /* not a special icode */
1063 ic->op == JUMPTABLE ||
1068 POINTER_SET (ic)) &&
1069 (result = OP_SYMBOL (IC_RESULT (ic))) && /* has a result */
1070 result->liveTo > ic->seq && /* and will live beyond this */
1071 result->liveTo <= ebp->lSeq && /* does not go beyond this block */
1072 result->liveFrom == ic->seq && /* does not start before here */
1073 result->regType == sym->regType && /* same register types */
1074 result->nRegs && /* which needs registers */
1075 !result->isspilt && /* and does not already have them */
1077 !bitVectBitValue (_G.regAssigned, result->key) &&
1078 /* the number of free regs + number of regs in this LR
1079 can accomodate the what result Needs */
1080 ((nfreeRegsType (result->regType) +
1081 sym->nRegs) >= result->nRegs)
1085 for (i = 0; i < result->nRegs; i++)
1087 result->regs[i] = sym->regs[i];
1089 result->regs[i] = getRegGpr (ic, ebp, result);
1091 _G.regAssigned = bitVectSetBit (_G.regAssigned, result->key);
1092 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, result->key);
1096 /* free the remaining */
1097 for (; i < sym->nRegs; i++)
1101 if (!symHasReg (psym, sym->regs[i]))
1102 freeReg (sym->regs[i]);
1105 freeReg (sym->regs[i]);
1112 /*-----------------------------------------------------------------*/
1113 /* reassignLR - reassign this to registers */
1114 /*-----------------------------------------------------------------*/
1116 reassignLR (operand * op)
1118 symbol *sym = OP_SYMBOL (op);
1121 /* not spilt any more */
1122 sym->isspilt = sym->spillA = sym->blockSpil = sym->remainSpil = 0;
1123 bitVectUnSetBit (_G.spiltSet, sym->key);
1125 _G.regAssigned = bitVectSetBit (_G.regAssigned, sym->key);
1126 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, sym->key);
1130 for (i = 0; i < sym->nRegs; i++)
1131 sym->regs[i]->isFree = 0;
1134 /*-----------------------------------------------------------------*/
1135 /* willCauseSpill - determines if allocating will cause a spill */
1136 /*-----------------------------------------------------------------*/
1138 willCauseSpill (int nr, int rt)
1140 /* first check if there are any available registers
1141 of the type required */
1144 /* special case for pointer type
1145 if pointer type not avlb then
1146 check for type gpr */
1147 if (nFreeRegs (rt) >= nr)
1149 if (nFreeRegs (REG_GPR) >= nr)
1152 else if (rt == REG_BIT)
1154 if (nFreeRegs (rt) >= nr)
1159 if (mcs51_ptrRegReq)
1161 if (nFreeRegs (rt) >= nr)
1166 if (nFreeRegs (REG_PTR) +
1167 nFreeRegs (REG_GPR) >= nr)
1172 /* it will cause a spil */
1176 /*-----------------------------------------------------------------*/
1177 /* positionRegs - the allocator can allocate same registers to res- */
1178 /* ult and operand, if this happens make sure they are in the same */
1179 /* position as the operand otherwise chaos results */
1180 /*-----------------------------------------------------------------*/
1182 positionRegs (symbol * result, symbol * opsym)
1184 int count = min (result->nRegs, opsym->nRegs);
1185 int i, j = 0, shared = 0;
1188 /* if the result has been spilt then cannot share */
1193 /* first make sure that they actually share */
1194 for (i = 0; i < count; i++)
1196 for (j = 0; j < count; j++)
1198 if (result->regs[i] == opsym->regs[j] && i != j)
1208 regs *tmp = result->regs[i];
1209 result->regs[i] = result->regs[j];
1210 result->regs[j] = tmp;
1217 /*------------------------------------------------------------------*/
1218 /* verifyRegsAssigned - make sure an iTemp is properly initialized; */
1219 /* it should either have registers or have beed spilled. Otherwise, */
1220 /* there was an uninitialized variable, so just spill this to get */
1221 /* the operand in a valid state. */
1222 /*------------------------------------------------------------------*/
1224 verifyRegsAssigned (operand *op, iCode * ic)
1229 if (!IS_ITEMP (op)) return;
1231 sym = OP_SYMBOL (op);
1232 if (sym->isspilt) return;
1233 if (!sym->nRegs) return;
1234 if (sym->regs[0]) return;
1236 werrorfl (ic->filename, ic->lineno, W_LOCAL_NOINIT,
1237 sym->prereqv ? sym->prereqv->name : sym->name);
1242 /*-----------------------------------------------------------------*/
1243 /* serialRegAssign - serially allocate registers to the variables */
1244 /*-----------------------------------------------------------------*/
1246 serialRegAssign (eBBlock ** ebbs, int count)
1250 /* for all blocks */
1251 for (i = 0; i < count; i++)
1256 if (ebbs[i]->noPath &&
1257 (ebbs[i]->entryLabel != entryLabel &&
1258 ebbs[i]->entryLabel != returnLabel))
1261 /* for all instructions do */
1262 for (ic = ebbs[i]->sch; ic; ic = ic->next)
1266 /* if this is an ipop that means some live
1267 range will have to be assigned again */
1269 reassignLR (IC_LEFT (ic));
1271 /* if result is present && is a true symbol */
1272 if (IC_RESULT (ic) && ic->op != IFX &&
1273 IS_TRUE_SYMOP (IC_RESULT (ic)))
1274 OP_SYMBOL (IC_RESULT (ic))->allocreq++;
1276 /* take away registers from live
1277 ranges that end at this instruction */
1278 deassignLRs (ic, ebbs[i]);
1280 /* some don't need registers */
1281 if (SKIP_IC2 (ic) ||
1282 ic->op == JUMPTABLE ||
1286 (IC_RESULT (ic) && POINTER_SET (ic)))
1289 /* now we need to allocate registers
1290 only for the result */
1291 if (IC_RESULT (ic)) {
1292 symbol *sym = OP_SYMBOL (IC_RESULT (ic));
1298 /* Make sure any spill location is definitely allocated */
1299 if (sym->isspilt && !sym->remat && sym->usl.spillLoc &&
1300 !sym->usl.spillLoc->allocreq)
1302 sym->usl.spillLoc->allocreq++;
1305 /* if it does not need or is spilt
1306 or is already assigned to registers
1307 or will not live beyond this instructions */
1310 bitVectBitValue (_G.regAssigned, sym->key) ||
1311 sym->liveTo <= ic->seq)
1314 /* if some liverange has been spilt at the block level
1315 and this one live beyond this block then spil this
1317 if (_G.blockSpil && sym->liveTo > ebbs[i]->lSeq) {
1322 willCS = willCauseSpill (sym->nRegs, sym->regType);
1323 /* if this is a bit variable then don't use precious registers
1324 along with expensive bit-to-char conversions but just spill
1326 if (willCS && SPEC_NOUN(sym->etype) == V_BIT) {
1331 /* if trying to allocate this will cause
1332 a spill and there is nothing to spill
1333 or this one is rematerializable then
1335 spillable = computeSpillable (ic);
1336 if (sym->remat || (willCS && bitVectIsZero (spillable))) {
1341 /* If the live range preceeds the point of definition
1342 then ideally we must take into account registers that
1343 have been allocated after sym->liveFrom but freed
1344 before ic->seq. This is complicated, so spill this
1345 symbol instead and let fillGaps handle the allocation. */
1346 if (sym->liveFrom < ic->seq) {
1351 /* if it has a spillocation & is used less than
1352 all other live ranges then spill this */
1354 if (sym->usl.spillLoc) {
1355 symbol *leastUsed = leastUsedLR (liveRangesWith (spillable,
1356 allLRs, ebbs[i], ic));
1357 if (leastUsed && leastUsed->used > sym->used) {
1362 /* if none of the liveRanges have a spillLocation then better
1363 to spill this one than anything else already assigned to registers */
1364 if (liveRangesWith(spillable,noSpilLoc,ebbs[i],ic)) {
1365 /* if this is local to this block then we might find a block spil */
1366 if (!(sym->liveFrom >= ebbs[i]->fSeq && sym->liveTo <= ebbs[i]->lSeq)) {
1373 /* if we need ptr regs for the right side
1375 if (POINTER_GET (ic) && IS_SYMOP (IC_LEFT (ic))
1376 && getSize (OP_SYMBOL (IC_LEFT (ic))->type) <= (unsigned int) PTRSIZE) {
1380 if (IC_LEFT (ic) && IS_SYMOP (IC_LEFT (ic))
1381 && SPEC_OCLS(OP_SYMBOL (IC_LEFT (ic))->etype) == idata) {
1385 if (IC_RIGHT (ic) && IS_SYMOP (IC_RIGHT (ic))
1386 && SPEC_OCLS(OP_SYMBOL (IC_RIGHT (ic))->etype) == idata) {
1391 /* else we assign registers to it */
1392 _G.regAssigned = bitVectSetBit (_G.regAssigned, sym->key);
1393 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, sym->key);
1395 for (j = 0; j < sym->nRegs; j++) {
1396 sym->regs[j] = NULL;
1397 if (sym->regType == REG_PTR)
1398 sym->regs[j] = getRegPtr (ic, ebbs[i], sym);
1399 else if (sym->regType == REG_BIT)
1400 sym->regs[j] = getRegBit (sym);
1403 if (ic->op == CAST && IS_SYMOP (IC_RIGHT (ic)))
1405 symbol * right = OP_SYMBOL (IC_RIGHT (ic));
1407 if (right->regs[j] && (right->regType != REG_BIT))
1408 sym->regs[j] = allocThisReg (right->regs[j]);
1411 sym->regs[j] = getRegGpr (ic, ebbs[i], sym);
1414 /* if the allocation failed which means
1415 this was spilt then break */
1419 for (i=0; i < sym->nRegs ; i++ )
1420 sym->regs[i] = NULL;
1425 if (!POINTER_SET(ic) && !POINTER_GET(ic)) {
1426 /* if it shares registers with operands make sure
1427 that they are in the same position */
1428 if (IC_LEFT (ic) && IS_SYMOP (IC_LEFT (ic)) &&
1429 OP_SYMBOL (IC_LEFT (ic))->nRegs) {
1430 positionRegs (OP_SYMBOL (IC_RESULT (ic)),
1431 OP_SYMBOL (IC_LEFT (ic)));
1433 /* do the same for the right operand */
1434 if (IC_RIGHT (ic) && IS_SYMOP (IC_RIGHT (ic)) &&
1435 OP_SYMBOL (IC_RIGHT (ic))->nRegs) {
1436 positionRegs (OP_SYMBOL (IC_RESULT (ic)),
1437 OP_SYMBOL (IC_RIGHT (ic)));
1450 /* Check for and fix any problems with uninitialized operands */
1451 for (i = 0; i < count; i++)
1455 if (ebbs[i]->noPath &&
1456 (ebbs[i]->entryLabel != entryLabel &&
1457 ebbs[i]->entryLabel != returnLabel))
1460 for (ic = ebbs[i]->sch; ic; ic = ic->next)
1467 verifyRegsAssigned (IC_COND (ic), ic);
1471 if (ic->op == JUMPTABLE)
1473 verifyRegsAssigned (IC_JTCOND (ic), ic);
1477 verifyRegsAssigned (IC_RESULT (ic), ic);
1478 verifyRegsAssigned (IC_LEFT (ic), ic);
1479 verifyRegsAssigned (IC_RIGHT (ic), ic);
1484 /*-----------------------------------------------------------------*/
1485 /* fillGaps - Try to fill in the Gaps left by Pass1 */
1486 /*-----------------------------------------------------------------*/
1487 static void fillGaps()
1494 if (getenv("DISABLE_FILL_GAPS")) return;
1496 /* look for liveranges that were spilt by the allocator */
1497 for (sym = hTabFirstItem(liveRanges,&key) ; sym ;
1498 sym = hTabNextItem(liveRanges,&key)) {
1503 if (!sym->spillA || !sym->clashes || sym->remat) continue ;
1505 /* find the liveRanges this one clashes with, that are
1506 still assigned to registers & mark the registers as used*/
1507 for ( i = 0 ; i < sym->clashes->size ; i ++) {
1511 if (bitVectBitValue(sym->clashes,i) == 0 || /* those that clash with this */
1512 bitVectBitValue(_G.totRegAssigned,i) == 0) /* and are still assigned to registers */
1515 clr = hTabItemWithKey(liveRanges,i);
1518 /* mark these registers as used */
1519 for (k = 0 ; k < clr->nRegs ; k++ )
1520 useReg(clr->regs[k]);
1523 if (willCauseSpill(sym->nRegs,sym->regType)) {
1524 /* NOPE :( clear all registers & and continue */
1530 for (i = 0 ; i < sym->defs->size ; i++ )
1532 if (bitVectBitValue(sym->defs,i))
1534 if (!(ic = hTabItemWithKey(iCodehTab,i)))
1541 D(printf("Attempting fillGaps on %s: [",sym->name));
1542 /* THERE IS HOPE !!!! */
1543 for (i=0; i < sym->nRegs ; i++ ) {
1544 if (sym->regType == REG_PTR)
1545 sym->regs[i] = getRegPtrNoSpil ();
1546 else if (sym->regType == REG_BIT)
1547 sym->regs[i] = getRegBitNoSpil ();
1550 sym->regs[i] = NULL;
1551 if (ic && ic->op == CAST && IS_SYMOP (IC_RIGHT (ic)))
1553 symbol * right = OP_SYMBOL (IC_RIGHT (ic));
1556 sym->regs[i] = allocThisReg (right->regs[i]);
1559 sym->regs[i] = getRegGprNoSpil ();
1561 D(printf("%s ", sym->regs[i]->name));
1565 /* For all its definitions check if the registers
1566 allocated needs positioning NOTE: we can position
1567 only ONCE if more than One positioning required
1569 We may need to perform the checks twice; once to
1570 position the registers as needed, the second to
1571 verify any register repositioning is still
1575 for (pass=0; pass<2; pass++) {
1576 D(printf(" checking definitions\n"));
1577 for (i = 0 ; i < sym->defs->size ; i++ ) {
1578 if (bitVectBitValue(sym->defs,i)) {
1579 if (!(ic = hTabItemWithKey(iCodehTab,i))) continue ;
1580 D(printf(" ic->seq = %d\n", ic->seq));
1581 if (SKIP_IC(ic)) continue;
1582 assert(isSymbolEqual(sym,OP_SYMBOL(IC_RESULT(ic)))); /* just making sure */
1583 /* if left is assigned to registers */
1584 if (IS_SYMOP(IC_LEFT(ic)))
1586 D(printf(" left = "));
1587 D(printOperand(IC_LEFT(ic),NULL));
1589 if (IS_SYMOP(IC_LEFT(ic)) &&
1590 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_LEFT(ic))->key)) {
1591 pdone += (positionRegs(sym,OP_SYMBOL(IC_LEFT(ic)))>0);
1593 if (IS_SYMOP(IC_RIGHT(ic)))
1595 D(printf(" right = "));
1596 D(printOperand(IC_RIGHT(ic),NULL));
1598 if (IS_SYMOP(IC_RIGHT(ic)) &&
1599 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_RIGHT(ic))->key)) {
1600 pdone += (positionRegs(sym,OP_SYMBOL(IC_RIGHT(ic)))>0);
1602 D(printf(" pdone = %d\n", pdone));
1603 if (pdone > 1) break;
1606 D(printf(" checking uses\n"));
1607 for (i = 0 ; i < sym->uses->size ; i++ ) {
1608 if (bitVectBitValue(sym->uses,i)) {
1610 if (!(ic = hTabItemWithKey(iCodehTab,i))) continue ;
1611 D(printf(" ic->seq = %d\n", ic->seq));
1612 if (SKIP_IC(ic)) continue;
1613 if (POINTER_SET(ic) || POINTER_GET(ic)) continue ;
1615 /* if result is assigned to registers */
1616 if (IS_SYMOP(IC_RESULT(ic)))
1618 D(printf(" result = "));
1619 D(printOperand(IC_RESULT(ic),NULL));
1621 if (IS_SYMOP(IC_RESULT(ic)) &&
1622 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_RESULT(ic))->key)) {
1623 pdone += (positionRegs(sym,OP_SYMBOL(IC_RESULT(ic)))>0);
1625 D(printf(" pdone = %d\n", pdone));
1626 if (pdone > 1) break;
1629 if (pdone == 0) break; /* second pass only if regs repositioned */
1630 if (pdone > 1) break;
1632 D(printf(" sym->regs = ["));
1633 for (i=0; i < sym->nRegs ; i++ )
1634 D(printf("%s ", sym->regs[i]->name));
1636 /* had to position more than once GIVE UP */
1638 /* UNDO all the changes we made to try this */
1640 for (i=0; i < sym->nRegs ; i++ ) {
1641 sym->regs[i] = NULL;
1644 D(printf ("Fill Gap gave up due to positioning for %s in function %s\n",sym->name, currFunc ? currFunc->name : "UNKNOWN"));
1647 D(printf ("FILLED GAP for %s in function %s\n",sym->name, currFunc ? currFunc->name : "UNKNOWN"));
1649 _G.totRegAssigned = bitVectSetBit(_G.totRegAssigned,sym->key);
1650 sym->isspilt = sym->spillA = 0 ;
1651 sym->usl.spillLoc->allocreq--;
1656 /*-----------------------------------------------------------------*/
1657 /* findAllBitregs :- returns bit vector of all bit registers */
1658 /*-----------------------------------------------------------------*/
1660 findAllBitregs (void)
1662 bitVect *rmask = newBitVect (mcs51_nRegs);
1665 for (j = 0; j < mcs51_nRegs; j++)
1667 if (regs8051[j].type == REG_BIT)
1668 rmask = bitVectSetBit (rmask, regs8051[j].rIdx);
1674 /*-----------------------------------------------------------------*/
1675 /* mcs51_allBitregs :- returns bit vector of all bit registers */
1676 /*-----------------------------------------------------------------*/
1678 mcs51_allBitregs (void)
1680 return _G.allBitregs;
1683 /*-----------------------------------------------------------------*/
1684 /* rUmaskForOp :- returns register mask for an operand */
1685 /*-----------------------------------------------------------------*/
1687 mcs51_rUmaskForOp (operand * op)
1693 /* only temporaries are assigned registers */
1697 sym = OP_SYMBOL (op);
1699 /* if spilt or no registers assigned to it
1701 if (sym->isspilt || !sym->nRegs)
1704 rumask = newBitVect (mcs51_nRegs);
1706 for (j = 0; j < sym->nRegs; j++)
1708 if (sym->regs[j]) /* EEP - debug */
1709 rumask = bitVectSetBit (rumask, sym->regs[j]->rIdx);
1715 /*-----------------------------------------------------------------*/
1716 /* regsUsedIniCode :- returns bit vector of registers used in iCode */
1717 /*-----------------------------------------------------------------*/
1719 regsUsedIniCode (iCode * ic)
1721 bitVect *rmask = newBitVect (mcs51_nRegs);
1723 /* do the special cases first */
1726 rmask = bitVectUnion (rmask,
1727 mcs51_rUmaskForOp (IC_COND (ic)));
1731 /* for the jumptable */
1732 if (ic->op == JUMPTABLE)
1734 rmask = bitVectUnion (rmask,
1735 mcs51_rUmaskForOp (IC_JTCOND (ic)));
1740 /* of all other cases */
1742 rmask = bitVectUnion (rmask,
1743 mcs51_rUmaskForOp (IC_LEFT (ic)));
1747 rmask = bitVectUnion (rmask,
1748 mcs51_rUmaskForOp (IC_RIGHT (ic)));
1751 rmask = bitVectUnion (rmask,
1752 mcs51_rUmaskForOp (IC_RESULT (ic)));
1758 /*-----------------------------------------------------------------*/
1759 /* createRegMask - for each instruction will determine the regsUsed */
1760 /*-----------------------------------------------------------------*/
1762 createRegMask (eBBlock ** ebbs, int count)
1766 /* for all blocks */
1767 for (i = 0; i < count; i++)
1771 if (ebbs[i]->noPath &&
1772 (ebbs[i]->entryLabel != entryLabel &&
1773 ebbs[i]->entryLabel != returnLabel))
1776 /* for all instructions */
1777 for (ic = ebbs[i]->sch; ic; ic = ic->next)
1782 if (SKIP_IC2 (ic) || !ic->rlive)
1785 /* first mark the registers used in this
1787 ic->rUsed = regsUsedIniCode (ic);
1788 _G.funcrUsed = bitVectUnion (_G.funcrUsed, ic->rUsed);
1790 /* now create the register mask for those
1791 registers that are in use : this is a
1792 super set of ic->rUsed */
1793 ic->rMask = newBitVect (mcs51_nRegs + 1);
1795 /* for all live Ranges alive at this point */
1796 for (j = 1; j < ic->rlive->size; j++)
1801 /* if not alive then continue */
1802 if (!bitVectBitValue (ic->rlive, j))
1805 /* find the live range we are interested in */
1806 if (!(sym = hTabItemWithKey (liveRanges, j)))
1808 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
1809 "createRegMask cannot find live range");
1810 fprintf(stderr, "\tmissing live range: key=%d\n", j);
1814 /* if no register assigned to it */
1815 if (!sym->nRegs || sym->isspilt)
1818 /* for all the registers allocated to it */
1819 for (k = 0; k < sym->nRegs; k++)
1822 bitVectSetBit (ic->rMask, sym->regs[k]->rIdx);
1828 /*-----------------------------------------------------------------*/
1829 /* rematStr - returns the rematerialized string for a remat var */
1830 /*-----------------------------------------------------------------*/
1832 rematStr (symbol * sym)
1834 iCode *ic = sym->rematiCode;
1839 /* if plus adjust offset to right hand side */
1842 offset += (int) operandLitValue (IC_RIGHT (ic));
1843 ic = OP_SYMBOL (IC_LEFT (ic))->rematiCode;
1847 /* if minus adjust offset to right hand side */
1850 offset -= (int) operandLitValue (IC_RIGHT (ic));
1851 ic = OP_SYMBOL (IC_LEFT (ic))->rematiCode;
1855 /* cast then continue */
1856 if (IS_CAST_ICODE(ic)) {
1857 ic = OP_SYMBOL (IC_RIGHT (ic))->rematiCode;
1860 /* we reached the end */
1866 SNPRINTF (buffer, sizeof(buffer),
1868 OP_SYMBOL (IC_LEFT (ic))->rname,
1869 offset >= 0 ? '+' : '-',
1870 abs (offset) & 0xffff);
1874 strncpyz (buffer, OP_SYMBOL (IC_LEFT (ic))->rname, sizeof(buffer));
1879 /*-----------------------------------------------------------------*/
1880 /* regTypeNum - computes the type & number of registers required */
1881 /*-----------------------------------------------------------------*/
1883 regTypeNum (eBBlock *ebbs)
1889 /* for each live range do */
1890 for (sym = hTabFirstItem (liveRanges, &k); sym;
1891 sym = hTabNextItem (liveRanges, &k))
1894 /* if used zero times then no registers needed */
1895 if ((sym->liveTo - sym->liveFrom) == 0)
1899 /* if the live range is a temporary */
1903 /* if the type is marked as a conditional */
1904 if (sym->regType == REG_CND)
1907 /* if used in return only then we don't
1909 if (sym->ruonly || sym->accuse)
1911 if (IS_AGGREGATE (sym->type) || sym->isptr)
1912 sym->type = aggrToPtr (sym->type, FALSE);
1913 else if (IS_BIT(sym->type))
1914 sym->regType = REG_CND;
1918 /* if the symbol has only one definition &
1919 that definition is a get_pointer */
1920 if (bitVectnBitsOn (sym->defs) == 1 &&
1921 (ic = hTabItemWithKey (iCodehTab,
1922 bitVectFirstBit (sym->defs))) &&
1924 !IS_BITVAR (sym->etype) &&
1925 (aggrToPtrDclType (operandType (IC_LEFT (ic)), FALSE) == POINTER))
1928 if (ptrPseudoSymSafe (sym, ic))
1930 ptrPseudoSymConvert (sym, ic, rematStr (OP_SYMBOL (IC_LEFT (ic))));
1934 /* if in data space or idata space then try to
1935 allocate pointer register */
1939 /* if not then we require registers */
1940 sym->nRegs = ((IS_AGGREGATE (sym->type) || sym->isptr) ?
1941 getSize (sym->type = aggrToPtr (sym->type, FALSE)) :
1942 getSize (sym->type));
1946 fprintf (stderr, "allocated more than 4 or 0 registers for type ");
1947 printTypeChain (sym->type, stderr);
1948 fprintf (stderr, "\n");
1951 /* determine the type of register required */
1952 if (sym->nRegs == 1 && IS_PTR (sym->type) && sym->uptr)
1953 sym->regType = REG_PTR;
1954 else if (IS_BIT(sym->type))
1955 sym->regType = REG_BIT;
1957 sym->regType = REG_GPR;
1960 /* for the first run we don't provide */
1961 /* registers for true symbols we will */
1962 /* see how things go */
1968 /*-----------------------------------------------------------------*/
1969 /* freeAllRegs - mark all registers as free */
1970 /*-----------------------------------------------------------------*/
1976 for (i = 0; i < mcs51_nRegs; i++)
1977 regs8051[i].isFree = 1;
1980 /*-----------------------------------------------------------------*/
1981 /* deallocStackSpil - this will set the stack pointer back */
1982 /*-----------------------------------------------------------------*/
1984 DEFSETFUNC (deallocStackSpil)
1992 /*-----------------------------------------------------------------*/
1993 /* farSpacePackable - returns the packable icode for far variables */
1994 /*-----------------------------------------------------------------*/
1996 farSpacePackable (iCode * ic)
2000 /* go thru till we find a definition for the
2001 symbol on the right */
2002 for (dic = ic->prev; dic; dic = dic->prev)
2004 /* if the definition is a call then no */
2005 if ((dic->op == CALL || dic->op == PCALL) &&
2006 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
2011 /* if shift by unknown amount then not */
2012 if ((dic->op == LEFT_OP || dic->op == RIGHT_OP) &&
2013 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
2016 /* if pointer get and size > 1 */
2017 if (POINTER_GET (dic) &&
2018 getSize (aggrToPtr (operandType (IC_LEFT (dic)), FALSE)) > 1)
2021 if (POINTER_SET (dic) &&
2022 getSize (aggrToPtr (operandType (IC_RESULT (dic)), FALSE)) > 1)
2027 if (IC_COND (dic) &&
2028 IS_TRUE_SYMOP (IC_COND (dic)) &&
2029 isOperandInFarSpace (IC_COND (dic)))
2032 else if (dic->op == JUMPTABLE)
2034 if (IC_JTCOND (dic) &&
2035 IS_TRUE_SYMOP (IC_JTCOND (dic)) &&
2036 isOperandInFarSpace (IC_JTCOND (dic)))
2041 /* if any tree is a true symbol in far space */
2042 if (IC_RESULT (dic) &&
2043 IS_TRUE_SYMOP (IC_RESULT (dic)) &&
2044 isOperandInFarSpace (IC_RESULT (dic)))
2047 if (IC_RIGHT (dic) &&
2048 IS_TRUE_SYMOP (IC_RIGHT (dic)) &&
2049 isOperandInFarSpace (IC_RIGHT (dic)) &&
2050 !isOperandEqual (IC_RIGHT (dic), IC_RESULT (ic)))
2053 if (IC_LEFT (dic) &&
2054 IS_TRUE_SYMOP (IC_LEFT (dic)) &&
2055 isOperandInFarSpace (IC_LEFT (dic)) &&
2056 !isOperandEqual (IC_LEFT (dic), IC_RESULT (ic)))
2060 if (isOperandEqual (IC_RIGHT (ic), IC_RESULT (dic)))
2062 if ((dic->op == LEFT_OP ||
2063 dic->op == RIGHT_OP ||
2065 IS_OP_LITERAL (IC_RIGHT (dic)))
2075 /*-----------------------------------------------------------------*/
2076 /* packRegsForAssign - register reduction for assignment */
2077 /*-----------------------------------------------------------------*/
2079 packRegsForAssign (iCode * ic, eBBlock * ebp)
2083 if (!IS_ITEMP (IC_RIGHT (ic)) ||
2084 OP_SYMBOL (IC_RIGHT (ic))->isind ||
2085 OP_LIVETO (IC_RIGHT (ic)) > ic->seq)
2090 /* if the true symbol is defined in far space or on stack
2091 then we should not since this will increase register pressure */
2092 if (isOperandInFarSpace(IC_RESULT(ic)) && !farSpacePackable(ic)) {
2096 /* find the definition of iTempNN scanning backwards if we find a
2097 a use of the true symbol in before we find the definition then
2099 for (dic = ic->prev; dic; dic = dic->prev)
2101 int crossedCall = 0;
2103 /* We can pack across a function call only if it's a local */
2104 /* variable or our parameter. Never pack global variables */
2105 /* or parameters to a function we call. */
2106 if ((dic->op == CALL || dic->op == PCALL))
2108 if (!OP_SYMBOL (IC_RESULT (ic))->ismyparm
2109 && !OP_SYMBOL (IC_RESULT (ic))->islocal)
2115 /* Don't move an assignment out of a critical block */
2116 if (dic->op == CRITICAL)
2127 if (IS_SYMOP (IC_COND (dic)) &&
2128 (IC_COND (dic)->key == IC_RESULT (ic)->key ||
2129 IC_COND (dic)->key == IC_RIGHT (ic)->key))
2137 if (IS_TRUE_SYMOP (IC_RESULT (dic)) &&
2138 IS_OP_VOLATILE (IC_RESULT (dic)))
2144 if (IS_SYMOP (IC_RESULT (dic)) &&
2145 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
2147 if (POINTER_SET (dic))
2153 if (IS_SYMOP (IC_RIGHT (dic)) &&
2154 (IC_RIGHT (dic)->key == IC_RESULT (ic)->key ||
2155 IC_RIGHT (dic)->key == IC_RIGHT (ic)->key))
2161 if (IS_SYMOP (IC_LEFT (dic)) &&
2162 (IC_LEFT (dic)->key == IC_RESULT (ic)->key ||
2163 IC_LEFT (dic)->key == IC_RIGHT (ic)->key))
2169 if (IS_SYMOP (IC_RESULT (dic)) &&
2170 IC_RESULT (dic)->key == IC_RESULT (ic)->key)
2186 return 0; /* did not find */
2188 /* if assignment then check that right is not a bit */
2189 if (ASSIGNMENT (ic) && !POINTER_SET (ic))
2191 sym_link *etype = operandType (IC_RESULT (dic));
2192 if (IS_BITFIELD (etype))
2194 /* if result is a bit too then it's ok */
2195 etype = operandType (IC_RESULT (ic));
2196 if (!IS_BITFIELD (etype))
2203 /* if the result is on stack or iaccess then it must be
2204 the same atleast one of the operands */
2205 if (OP_SYMBOL (IC_RESULT (ic))->onStack ||
2206 OP_SYMBOL (IC_RESULT (ic))->iaccess)
2209 /* the operation has only one symbol
2210 operator then we can pack */
2211 if ((IC_LEFT (dic) && !IS_SYMOP (IC_LEFT (dic))) ||
2212 (IC_RIGHT (dic) && !IS_SYMOP (IC_RIGHT (dic))))
2215 if (!((IC_LEFT (dic) &&
2216 IC_RESULT (ic)->key == IC_LEFT (dic)->key) ||
2218 IC_RESULT (ic)->key == IC_RIGHT (dic)->key)))
2222 /* found the definition */
2223 /* replace the result with the result of */
2224 /* this assignment and remove this assignment */
2225 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2226 ReplaceOpWithCheaperOp(&IC_RESULT (dic), IC_RESULT (ic));
2228 if (IS_ITEMP (IC_RESULT (dic)) && OP_SYMBOL (IC_RESULT (dic))->liveFrom > dic->seq)
2230 OP_SYMBOL (IC_RESULT (dic))->liveFrom = dic->seq;
2232 // TODO: and the otherway around?
2234 /* delete from liverange table also
2235 delete from all the points inbetween and the new
2237 for (sic = dic; sic != ic; sic = sic->next)
2239 bitVectUnSetBit (sic->rlive, IC_RESULT (ic)->key);
2240 if (IS_ITEMP (IC_RESULT (dic)))
2241 bitVectSetBit (sic->rlive, IC_RESULT (dic)->key);
2244 remiCodeFromeBBlock (ebp, ic);
2245 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
2246 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
2247 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
2251 /*------------------------------------------------------------------*/
2252 /* findAssignToSym : scanning backwards looks for first assig found */
2253 /*------------------------------------------------------------------*/
2255 findAssignToSym (operand * op, iCode * ic)
2259 /* This routine is used to find sequences like
2261 ...; (intervening ops don't use iTempAA or modify FOO)
2262 blah = blah + iTempAA;
2264 and eliminate the use of iTempAA, freeing up its register for
2268 for (dic = ic->prev; dic; dic = dic->prev)
2271 /* if definition by assignment */
2272 if (dic->op == '=' &&
2273 !POINTER_SET (dic) &&
2274 IC_RESULT (dic)->key == op->key
2275 /* && IS_TRUE_SYMOP(IC_RIGHT(dic)) */
2277 break; /* found where this temp was defined */
2279 /* if we find an usage then we cannot delete it */
2283 if (IC_COND (dic) && IC_COND (dic)->key == op->key)
2286 else if (dic->op == JUMPTABLE)
2288 if (IC_JTCOND (dic) && IC_JTCOND (dic)->key == op->key)
2293 if (IC_LEFT (dic) && IC_LEFT (dic)->key == op->key)
2296 if (IC_RIGHT (dic) && IC_RIGHT (dic)->key == op->key)
2299 if (POINTER_SET (dic) && IC_RESULT (dic)->key == op->key)
2305 return NULL; /* didn't find any assignment to op */
2307 /* we are interested only if defined in far space */
2308 /* or in stack space in case of + & - */
2310 /* if assigned to a non-symbol then don't repack regs */
2311 if (!IS_SYMOP (IC_RIGHT (dic)))
2314 /* if the symbol is volatile then we should not */
2315 if (isOperandVolatile (IC_RIGHT (dic), TRUE))
2317 /* XXX TODO --- should we be passing FALSE to isOperandVolatile()?
2318 What does it mean for an iTemp to be volatile, anyway? Passing
2319 TRUE is more cautious but may prevent possible optimizations */
2321 /* if the symbol is in far space then we should not */
2322 if (isOperandInFarSpace (IC_RIGHT (dic)))
2325 /* for + & - operations make sure that
2326 if it is on the stack it is the same
2327 as one of the three operands */
2328 if ((ic->op == '+' || ic->op == '-') &&
2329 OP_SYMBOL (IC_RIGHT (dic))->onStack)
2332 if (IC_RESULT (ic)->key != IC_RIGHT (dic)->key &&
2333 IC_LEFT (ic)->key != IC_RIGHT (dic)->key &&
2334 IC_RIGHT (ic)->key != IC_RIGHT (dic)->key)
2338 /* now make sure that the right side of dic
2339 is not defined between ic & dic */
2342 iCode *sic = dic->next;
2344 for (; sic != ic; sic = sic->next)
2345 if (IC_RESULT (sic) &&
2346 IC_RESULT (sic)->key == IC_RIGHT (dic)->key)
2353 /*-----------------------------------------------------------------*/
2354 /* reassignAliasedSym - used by packRegsForSupport to replace */
2355 /* redundant iTemp with equivalent symbol */
2356 /*-----------------------------------------------------------------*/
2358 reassignAliasedSym (eBBlock *ebp, iCode *assignment, iCode *use, operand *op)
2361 unsigned oldSymKey, newSymKey;
2363 oldSymKey = op->key;
2364 newSymKey = IC_RIGHT(assignment)->key;
2366 /* only track live ranges of compiler-generated temporaries */
2367 if (!IS_ITEMP(IC_RIGHT(assignment)))
2370 /* update the live-value bitmaps */
2371 for (ic = assignment; ic != use; ic = ic->next) {
2372 bitVectUnSetBit (ic->rlive, oldSymKey);
2374 ic->rlive = bitVectSetBit (ic->rlive, newSymKey);
2377 /* update the sym of the used operand */
2378 OP_SYMBOL(op) = OP_SYMBOL(IC_RIGHT(assignment));
2379 op->key = OP_SYMBOL(op)->key;
2380 OP_SYMBOL(op)->accuse = 0;
2382 /* update the sym's liverange */
2383 if ( OP_LIVETO(op) < ic->seq )
2384 setToRange(op, ic->seq, FALSE);
2386 /* remove the assignment iCode now that its result is unused */
2387 remiCodeFromeBBlock (ebp, assignment);
2388 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(assignment))->defs, assignment->key);
2389 hTabDeleteItem (&iCodehTab, assignment->key, assignment, DELETE_ITEM, NULL);
2393 /*-----------------------------------------------------------------*/
2394 /* packRegsForSupport :- reduce some registers for support calls */
2395 /*-----------------------------------------------------------------*/
2397 packRegsForSupport (iCode * ic, eBBlock * ebp)
2401 /* for the left & right operand :- look to see if the
2402 left was assigned a true symbol in far space in that
2403 case replace them */
2405 if (IS_ITEMP (IC_LEFT (ic)) &&
2406 OP_SYMBOL (IC_LEFT (ic))->liveTo <= ic->seq)
2408 dic = findAssignToSym (IC_LEFT (ic), ic);
2412 /* found it we need to remove it from the block */
2413 reassignAliasedSym (ebp, dic, ic, IC_LEFT(ic));
2418 /* do the same for the right operand */
2419 if (IS_ITEMP (IC_RIGHT (ic)) &&
2420 OP_SYMBOL (IC_RIGHT (ic))->liveTo <= ic->seq)
2422 iCode *dic = findAssignToSym (IC_RIGHT (ic), ic);
2426 /* if this is a subtraction & the result
2427 is a true symbol in far space then don't pack */
2428 if (ic->op == '-' && IS_TRUE_SYMOP (IC_RESULT (dic)))
2430 sym_link *etype = getSpec (operandType (IC_RESULT (dic)));
2431 if (IN_FARSPACE (SPEC_OCLS (etype)))
2434 /* found it we need to remove it from the
2436 reassignAliasedSym (ebp, dic, ic, IC_RIGHT(ic));
2446 /*-----------------------------------------------------------------*/
2447 /* packRegsForOneuse : - will reduce some registers for single Use */
2448 /*-----------------------------------------------------------------*/
2450 packRegsForOneuse (iCode * ic, operand * op, eBBlock * ebp)
2454 /* if returning a literal then do nothing */
2458 /* if rematerializable or already return use then do nothing */
2459 if (OP_SYMBOL(op)->remat || OP_SYMBOL(op)->ruonly)
2462 /* only upto 2 bytes since we cannot predict
2463 the usage of b, & acc */
2464 if (getSize (operandType (op)) > (fReturnSizeMCS51 - 2))
2467 if (ic->op != RETURN &&
2469 !POINTER_SET (ic) &&
2473 if (ic->op == SEND && ic->argreg != 1) return NULL;
2475 /* this routine will mark the symbol as used in one
2476 instruction use only && if the definition is local
2477 (ie. within the basic block) && has only one definition &&
2478 that definition is either a return value from a
2479 function or does not contain any variables in
2481 if (bitVectnBitsOn (OP_USES (op)) > 1)
2484 /* if it has only one definition */
2485 if (bitVectnBitsOn (OP_DEFS (op)) > 1)
2486 return NULL; /* has more than one definition */
2488 /* get that definition */
2490 hTabItemWithKey (iCodehTab,
2491 bitVectFirstBit (OP_DEFS (op)))))
2494 /* if that only usage is a cast */
2495 if (dic->op == CAST) {
2496 /* to a bigger type */
2497 if (getSize(OP_SYM_TYPE(IC_RESULT(dic))) >
2498 getSize(OP_SYM_TYPE(IC_RIGHT(dic)))) {
2499 /* than we can not, since we cannot predict the usage of b & acc */
2504 /* found the definition now check if it is local */
2505 if (dic->seq < ebp->fSeq ||
2506 dic->seq > ebp->lSeq)
2507 return NULL; /* non-local */
2509 /* now check if it is the return from
2511 if (dic->op == CALL || dic->op == PCALL)
2513 if (ic->op != SEND && ic->op != RETURN &&
2514 !POINTER_SET(ic) && !POINTER_GET(ic))
2516 OP_SYMBOL (op)->ruonly = 1;
2522 /* otherwise check that the definition does
2523 not contain any symbols in far space */
2524 if (isOperandInFarSpace (IC_LEFT (dic)) ||
2525 isOperandInFarSpace (IC_RIGHT (dic)) ||
2526 IS_OP_RUONLY (IC_LEFT (ic)) ||
2527 IS_OP_RUONLY (IC_RIGHT (ic)))
2532 /* if pointer set then make sure the pointer
2534 if (POINTER_SET (dic) &&
2535 !IS_DATA_PTR (aggrToPtr (operandType (IC_RESULT (dic)), FALSE)))
2538 if (POINTER_GET (dic) &&
2539 !IS_DATA_PTR (aggrToPtr (operandType (IC_LEFT (dic)), FALSE)))
2543 /* Make sure no overlapping liverange is already assigned to DPTR */
2544 if (OP_SYMBOL(op)->clashes)
2549 for (i = 0 ; i < OP_SYMBOL(op)->clashes->size ; i++ )
2551 if (bitVectBitValue(OP_SYMBOL(op)->clashes,i))
2553 sym = hTabItemWithKey(liveRanges,i);
2562 /* also make sure the intervening instructions
2563 don't have anything in far space */
2564 for (dic = dic->next; dic && dic != ic && sic != ic; dic = dic->next)
2566 /* if there is an intervening function call then no */
2567 if (dic->op == CALL || dic->op == PCALL)
2569 /* if pointer set then make sure the pointer
2571 if (POINTER_SET (dic) &&
2572 !IS_DATA_PTR (aggrToPtr (operandType (IC_RESULT (dic)), FALSE)))
2575 if (POINTER_GET (dic) &&
2576 !IS_DATA_PTR (aggrToPtr (operandType (IC_LEFT (dic)), FALSE)))
2579 /* if address of & the result is remat the okay */
2580 if (dic->op == ADDRESS_OF &&
2581 OP_SYMBOL (IC_RESULT (dic))->remat)
2584 /* if operand has size of three or more & this
2585 operation is a '*','/' or '%' then 'b' may
2587 if ((dic->op == '%' || dic->op == '/' || dic->op == '*') &&
2588 getSize (operandType (op)) >= 3)
2591 /* if left or right or result is in far space */
2592 if (isOperandInFarSpace (IC_LEFT (dic)) ||
2593 isOperandInFarSpace (IC_RIGHT (dic)) ||
2594 isOperandInFarSpace (IC_RESULT (dic)) ||
2595 IS_OP_RUONLY (IC_LEFT (dic)) ||
2596 IS_OP_RUONLY (IC_RIGHT (dic)) ||
2597 IS_OP_RUONLY (IC_RESULT (dic)))
2601 /* if left or right or result is on stack */
2602 if (isOperandOnStack(IC_LEFT(dic)) ||
2603 isOperandOnStack(IC_RIGHT(dic)) ||
2604 isOperandOnStack(IC_RESULT(dic))) {
2609 OP_SYMBOL (op)->ruonly = 1;
2613 /*-----------------------------------------------------------------*/
2614 /* isBitwiseOptimizable - requirements of JEAN LOUIS VERN */
2615 /*-----------------------------------------------------------------*/
2617 isBitwiseOptimizable (iCode * ic)
2619 sym_link *ltype = getSpec (operandType (IC_LEFT (ic)));
2620 sym_link *rtype = getSpec (operandType (IC_RIGHT (ic)));
2622 /* bitwise operations are considered optimizable
2623 under the following conditions (Jean-Louis VERN)
2635 if (IS_LITERAL(rtype) ||
2636 (IS_BITVAR (ltype) && IN_BITSPACE (SPEC_OCLS (ltype))))
2642 /*-----------------------------------------------------------------*/
2643 /* isCommutativeOp - tests whether this op cares what order its */
2644 /* operands are in */
2645 /*-----------------------------------------------------------------*/
2646 bool isCommutativeOp(unsigned int op)
2648 if (op == '+' || op == '*' || op == EQ_OP ||
2649 op == '^' || op == '|' || op == BITWISEAND)
2655 /*-----------------------------------------------------------------*/
2656 /* operandUsesAcc - determines whether the code generated for this */
2657 /* operand will have to use the accumulator */
2658 /*-----------------------------------------------------------------*/
2659 bool operandUsesAcc(operand *op)
2665 symbol *sym = OP_SYMBOL(op);
2669 return TRUE; /* duh! */
2671 if (IN_STACK(sym->etype) || sym->onStack ||
2672 (SPIL_LOC(op) && SPIL_LOC(op)->onStack))
2673 return TRUE; /* acc is used to calc stack offset */
2678 sym = SPIL_LOC(op); /* if spilled, look at spill location */
2680 return FALSE; /* more checks? */
2684 symspace = SPEC_OCLS(sym->etype);
2686 if (sym->iaccess && symspace->paged)
2687 return TRUE; /* must fetch paged indirect sym via accumulator */
2689 if (IN_BITSPACE(symspace))
2690 return TRUE; /* fetching bit vars uses the accumulator */
2692 if (IN_FARSPACE(symspace) || IN_CODESPACE(symspace))
2693 return TRUE; /* fetched via accumulator and dptr */
2699 /*-----------------------------------------------------------------*/
2700 /* packRegsForAccUse - pack registers for acc use */
2701 /*-----------------------------------------------------------------*/
2703 packRegsForAccUse (iCode * ic)
2707 /* if this is an aggregate, e.g. a one byte char array */
2708 if (IS_AGGREGATE(operandType(IC_RESULT(ic)))) {
2712 /* if we are calling a reentrant function that has stack parameters */
2713 if (ic->op == CALL &&
2714 IFFUNC_ISREENT(operandType(IC_LEFT(ic))) &&
2715 FUNC_HASSTACKPARM(operandType(IC_LEFT(ic))))
2718 if (ic->op == PCALL &&
2719 IFFUNC_ISREENT(operandType(IC_LEFT(ic))->next) &&
2720 FUNC_HASSTACKPARM(operandType(IC_LEFT(ic))->next))
2723 /* if + or - then it has to be one byte result */
2724 if ((ic->op == '+' || ic->op == '-')
2725 && getSize (operandType (IC_RESULT (ic))) > 1)
2728 /* if shift operation make sure right side is not a literal */
2729 if (ic->op == RIGHT_OP &&
2730 (isOperandLiteral (IC_RIGHT (ic)) ||
2731 getSize (operandType (IC_RESULT (ic))) > 1))
2734 if (ic->op == LEFT_OP &&
2735 (isOperandLiteral (IC_RIGHT (ic)) ||
2736 getSize (operandType (IC_RESULT (ic))) > 1))
2739 if (IS_BITWISE_OP (ic) &&
2740 getSize (operandType (IC_RESULT (ic))) > 1)
2744 /* has only one definition */
2745 if (bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) > 1)
2748 /* has only one use */
2749 if (bitVectnBitsOn (OP_USES (IC_RESULT (ic))) > 1)
2752 /* and the usage immediately follows this iCode */
2753 if (!(uic = hTabItemWithKey (iCodehTab,
2754 bitVectFirstBit (OP_USES (IC_RESULT (ic))))))
2757 if (ic->next != uic)
2760 /* if it is a conditional branch then we definitely can */
2764 if (uic->op == JUMPTABLE)
2767 if (POINTER_SET (uic) &&
2768 getSize (aggrToPtr (operandType (IC_RESULT (uic)), FALSE)) > 1)
2771 /* if the usage is not an assignment
2772 or an arithmetic / bitwise / shift operation then not */
2773 if (uic->op != '=' &&
2774 !IS_ARITHMETIC_OP (uic) &&
2775 !IS_BITWISE_OP (uic) &&
2776 uic->op != LEFT_OP &&
2777 uic->op != RIGHT_OP)
2780 /* if used in ^ operation then make sure right is not a
2781 literal (WIML: Why is this?) */
2782 if (uic->op == '^' && isOperandLiteral (IC_RIGHT (uic)))
2785 /* if shift operation make sure right side is not a literal */
2786 /* WIML: Why is this? */
2787 if (uic->op == RIGHT_OP &&
2788 (isOperandLiteral (IC_RIGHT (uic)) ||
2789 getSize (operandType (IC_RESULT (uic))) > 1))
2791 if (uic->op == LEFT_OP &&
2792 (isOperandLiteral (IC_RIGHT (uic)) ||
2793 getSize (operandType (IC_RESULT (uic))) > 1))
2796 /* make sure that the result of this icode is not on the
2797 stack, since acc is used to compute stack offset */
2799 if (IS_TRUE_SYMOP (IC_RESULT (uic)) &&
2800 OP_SYMBOL (IC_RESULT (uic))->onStack)
2803 if (isOperandOnStack(IC_RESULT(uic)))
2807 /* if the usage has only one operand then we can */
2808 if (IC_LEFT (uic) == NULL ||
2809 IC_RIGHT (uic) == NULL)
2812 /* if the other operand uses the accumulator then we cannot */
2813 if ( (IC_LEFT(uic)->key == IC_RESULT(ic)->key &&
2814 operandUsesAcc(IC_RIGHT(uic))) ||
2815 (IC_RIGHT(uic)->key == IC_RESULT(ic)->key &&
2816 operandUsesAcc(IC_LEFT(uic))) )
2819 /* make sure this is on the left side if not commutative */
2820 /* except for '-', which has been written to be able to
2821 handle reversed operands */
2822 if (!(isCommutativeOp(ic->op) || ic->op == '-') &&
2823 IC_LEFT (uic)->key != IC_RESULT (ic)->key)
2827 // this is too dangerous and need further restrictions
2830 /* if one of them is a literal then we can */
2831 if ((IC_LEFT (uic) && IS_OP_LITERAL (IC_LEFT (uic))) ||
2832 (IC_RIGHT (uic) && IS_OP_LITERAL (IC_RIGHT (uic))))
2834 OP_SYMBOL (IC_RESULT (ic))->accuse = 1;
2840 OP_SYMBOL (IC_RESULT (ic))->accuse = 1;
2844 /*-----------------------------------------------------------------*/
2845 /* packForPush - heuristics to reduce iCode for pushing */
2846 /*-----------------------------------------------------------------*/
2848 packForPush (iCode * ic, eBBlock ** ebpp, int blockno)
2852 struct eBBlock * ebp=ebpp[blockno];
2854 if (ic->op != IPUSH || !IS_ITEMP (IC_LEFT (ic)))
2857 /* must have only definition & one usage */
2858 if (bitVectnBitsOn (OP_DEFS (IC_LEFT (ic))) != 1 ||
2859 bitVectnBitsOn (OP_USES (IC_LEFT (ic))) != 1)
2862 /* find the definition */
2863 if (!(dic = hTabItemWithKey (iCodehTab,
2864 bitVectFirstBit (OP_DEFS (IC_LEFT (ic))))))
2867 if (dic->op != '=' || POINTER_SET (dic))
2870 if (dic->seq < ebp->fSeq) { // Evelyn did this
2872 for (i=0; i<blockno; i++) {
2873 if (dic->seq >= ebpp[i]->fSeq && dic->seq <= ebpp[i]->lSeq) {
2878 wassert (i!=blockno); // no way to recover from here
2881 if (IS_SYMOP(IC_RIGHT(dic))) {
2882 /* make sure the right side does not have any definitions
2884 dbv = OP_DEFS(IC_RIGHT(dic));
2885 for (lic = ic; lic && lic != dic ; lic = lic->prev) {
2886 if (bitVectBitValue(dbv,lic->key))
2889 /* make sure they have the same type */
2890 if (IS_SPEC(operandType(IC_LEFT(ic))))
2892 sym_link *itype=operandType(IC_LEFT(ic));
2893 sym_link *ditype=operandType(IC_RIGHT(dic));
2895 if (SPEC_USIGN(itype)!=SPEC_USIGN(ditype) ||
2896 SPEC_LONG(itype)!=SPEC_LONG(ditype))
2899 /* extend the live range of replaced operand if needed */
2900 if (OP_SYMBOL(IC_RIGHT(dic))->liveTo < ic->seq) {
2901 OP_SYMBOL(IC_RIGHT(dic))->liveTo = ic->seq;
2903 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2906 /* we now we know that it has one & only one def & use
2907 and the that the definition is an assignment */
2908 ReplaceOpWithCheaperOp(&IC_LEFT (ic), IC_RIGHT (dic));
2909 remiCodeFromeBBlock (ebp, dic);
2910 hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
2913 /*-----------------------------------------------------------------*/
2914 /* packRegisters - does some transformations to reduce register */
2916 /*-----------------------------------------------------------------*/
2918 packRegisters (eBBlock ** ebpp, int blockno)
2922 eBBlock *ebp=ebpp[blockno];
2928 /* look for assignments of the form */
2929 /* iTempNN = TRueSym (someoperation) SomeOperand */
2931 /* TrueSym := iTempNN:1 */
2932 for (ic = ebp->sch; ic; ic = ic->next)
2934 /* find assignment of the form TrueSym := iTempNN:1 */
2935 if (ic->op == '=' && !POINTER_SET (ic))
2936 change += packRegsForAssign (ic, ebp);
2943 for (ic = ebp->sch; ic; ic = ic->next)
2945 /* Fix for bug #979599: */
2948 /* Look for two subsequent iCodes with */
2950 /* _c = iTemp & op; */
2951 /* and replace them by */
2954 if ((ic->op == BITWISEAND || ic->op == '|' || ic->op == '^') &&
2956 ic->prev->op == '=' &&
2957 IS_ITEMP (IC_LEFT (ic)) &&
2958 IC_LEFT (ic) == IC_RESULT (ic->prev) &&
2959 isOperandEqual (IC_RESULT(ic), IC_RIGHT(ic->prev)))
2961 iCode* ic_prev = ic->prev;
2962 symbol* prev_result_sym = OP_SYMBOL (IC_RESULT (ic_prev));
2964 ReplaceOpWithCheaperOp (&IC_LEFT (ic), IC_RESULT (ic));
2965 if (IC_RESULT (ic_prev) != IC_RIGHT (ic))
2967 bitVectUnSetBit (OP_USES (IC_RESULT (ic_prev)), ic->key);
2968 if (/*IS_ITEMP (IC_RESULT (ic_prev)) && */
2969 prev_result_sym->liveTo == ic->seq)
2971 prev_result_sym->liveTo = ic_prev->seq;
2974 bitVectSetBit (OP_USES (IC_RESULT (ic)), ic->key);
2976 bitVectSetBit (ic->rlive, IC_RESULT (ic)->key);
2978 if (bitVectIsZero (OP_USES (IC_RESULT (ic_prev))))
2980 bitVectUnSetBit (ic->rlive, IC_RESULT (ic)->key);
2981 bitVectUnSetBit (OP_DEFS (IC_RESULT (ic_prev)), ic_prev->key);
2982 remiCodeFromeBBlock (ebp, ic_prev);
2983 hTabDeleteItem (&iCodehTab, ic_prev->key, ic_prev, DELETE_ITEM, NULL);
2987 /* if this is an itemp & result of an address of a true sym
2988 then mark this as rematerialisable */
2989 if (ic->op == ADDRESS_OF &&
2990 IS_ITEMP (IC_RESULT (ic)) &&
2991 IS_TRUE_SYMOP (IC_LEFT (ic)) &&
2992 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1 &&
2993 !OP_SYMBOL (IC_LEFT (ic))->onStack)
2995 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2996 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2997 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
3000 /* if straight assignment then carry remat flag if
3001 this is the only definition */
3002 if (ic->op == '=' &&
3003 !POINTER_SET (ic) &&
3004 IS_SYMOP (IC_RIGHT (ic)) &&
3005 OP_SYMBOL (IC_RIGHT (ic))->remat &&
3006 !IS_CAST_ICODE(OP_SYMBOL (IC_RIGHT (ic))->rematiCode) &&
3007 bitVectnBitsOn (OP_SYMBOL (IC_RESULT (ic))->defs) <= 1)
3009 OP_SYMBOL (IC_RESULT (ic))->remat =
3010 OP_SYMBOL (IC_RIGHT (ic))->remat;
3011 OP_SYMBOL (IC_RESULT (ic))->rematiCode =
3012 OP_SYMBOL (IC_RIGHT (ic))->rematiCode;
3015 /* if cast to a generic pointer & the pointer being
3016 cast is remat, then we can remat this cast as well */
3017 if (ic->op == CAST &&
3018 IS_SYMOP(IC_RIGHT(ic)) &&
3019 OP_SYMBOL(IC_RIGHT(ic))->remat &&
3020 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1)
3022 sym_link *to_type = operandType(IC_LEFT(ic));
3023 sym_link *from_type = operandType(IC_RIGHT(ic));
3024 if (IS_GENPTR(to_type) && IS_PTR(from_type))
3026 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
3027 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
3028 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
3032 /* if this is a +/- operation with a rematerizable
3033 then mark this as rematerializable as well */
3034 if ((ic->op == '+' || ic->op == '-') &&
3035 (IS_SYMOP (IC_LEFT (ic)) &&
3036 IS_ITEMP (IC_RESULT (ic)) &&
3037 IS_OP_LITERAL (IC_RIGHT (ic))) &&
3038 OP_SYMBOL (IC_LEFT (ic))->remat &&
3039 (!IS_SYMOP (IC_RIGHT (ic)) || !IS_CAST_ICODE(OP_SYMBOL (IC_RIGHT (ic))->rematiCode)) &&
3040 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1)
3042 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
3043 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
3044 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
3047 /* mark the pointer usages */
3048 if (POINTER_SET (ic))
3049 OP_SYMBOL (IC_RESULT (ic))->uptr = 1;
3051 if (POINTER_GET (ic) && IS_SYMOP(IC_LEFT (ic)))
3052 OP_SYMBOL (IC_LEFT (ic))->uptr = 1;
3056 /* if we are using a symbol on the stack
3057 then we should say mcs51_ptrRegReq */
3058 if (options.useXstack && ic->parmPush
3059 && (ic->op == IPUSH || ic->op == IPOP))
3061 if (ic->op == IFX && IS_SYMOP (IC_COND (ic)))
3062 mcs51_ptrRegReq += ((OP_SYMBOL (IC_COND (ic))->onStack ||
3063 OP_SYMBOL (IC_COND (ic))->iaccess ||
3064 SPEC_OCLS(OP_SYMBOL (IC_COND (ic))->etype) == idata) ? 1 : 0);
3065 else if (ic->op == JUMPTABLE && IS_SYMOP (IC_JTCOND (ic)))
3066 mcs51_ptrRegReq += ((OP_SYMBOL (IC_JTCOND (ic))->onStack ||
3067 OP_SYMBOL (IC_JTCOND (ic))->iaccess ||
3068 SPEC_OCLS(OP_SYMBOL (IC_JTCOND (ic))->etype) == idata) ? 1 : 0);
3071 if (IS_SYMOP (IC_LEFT (ic)))
3072 mcs51_ptrRegReq += ((OP_SYMBOL (IC_LEFT (ic))->onStack ||
3073 OP_SYMBOL (IC_LEFT (ic))->iaccess ||
3074 SPEC_OCLS(OP_SYMBOL (IC_LEFT (ic))->etype) == idata) ? 1 : 0);
3075 if (IS_SYMOP (IC_RIGHT (ic)))
3076 mcs51_ptrRegReq += ((OP_SYMBOL (IC_RIGHT (ic))->onStack ||
3077 OP_SYMBOL (IC_RIGHT (ic))->iaccess ||
3078 SPEC_OCLS(OP_SYMBOL (IC_RIGHT (ic))->etype) == idata) ? 1 : 0);
3079 if (IS_SYMOP (IC_RESULT (ic)))
3080 mcs51_ptrRegReq += ((OP_SYMBOL (IC_RESULT (ic))->onStack ||
3081 OP_SYMBOL (IC_RESULT (ic))->iaccess ||
3082 SPEC_OCLS(OP_SYMBOL (IC_RESULT (ic))->etype) == idata) ? 1 : 0);
3083 if (POINTER_GET (ic) && IS_SYMOP (IC_LEFT (ic))
3084 && getSize (OP_SYMBOL (IC_LEFT (ic))->type) <= (unsigned int) PTRSIZE)
3086 if (POINTER_SET (ic) && IS_SYMOP (IC_RESULT (ic))
3087 && getSize (OP_SYMBOL (IC_RESULT (ic))->type) <= (unsigned int) PTRSIZE)
3092 /* if the condition of an if instruction
3093 is defined in the previous instruction and
3094 this is the only usage then
3095 mark the itemp as a conditional */
3096 if ((IS_CONDITIONAL (ic) ||
3097 (IS_BITWISE_OP(ic) && isBitwiseOptimizable (ic))) &&
3098 ic->next && ic->next->op == IFX &&
3099 bitVectnBitsOn (OP_USES(IC_RESULT(ic)))==1 &&
3100 isOperandEqual (IC_RESULT (ic), IC_COND (ic->next)) &&
3101 OP_SYMBOL (IC_RESULT (ic))->liveTo <= ic->next->seq)
3103 OP_SYMBOL (IC_RESULT (ic))->regType = REG_CND;
3107 /* if the condition of an if instruction
3108 is defined in the previous GET_POINTER instruction and
3109 this is the only usage then
3110 mark the itemp as accumulator use */
3111 if ((POINTER_GET (ic) && getSize (operandType (IC_RESULT (ic))) <=1) &&
3112 ic->next && ic->next->op == IFX &&
3113 bitVectnBitsOn (OP_USES(IC_RESULT(ic)))==1 &&
3114 isOperandEqual (IC_RESULT (ic), IC_COND (ic->next)) &&
3115 OP_SYMBOL (IC_RESULT (ic))->liveTo <= ic->next->seq)
3117 OP_SYMBOL (IC_RESULT (ic))->accuse = 1;
3121 /* reduce for support function calls */
3122 if (ic->supportRtn || ic->op == '+' || ic->op == '-')
3123 packRegsForSupport (ic, ebp);
3125 /* some cases the redundant moves can
3126 can be eliminated for return statements */
3127 if ((ic->op == RETURN || (ic->op == SEND && ic->argreg == 1)) &&
3128 !isOperandInFarSpace (IC_LEFT (ic)) &&
3129 options.model == MODEL_SMALL) {
3130 packRegsForOneuse (ic, IC_LEFT (ic), ebp);
3133 /* if pointer set & left has a size more than
3134 one and right is not in far space */
3135 if (POINTER_SET (ic) &&
3136 !isOperandInFarSpace (IC_RIGHT (ic)) &&
3137 !OP_SYMBOL (IC_RESULT (ic))->remat &&
3138 !IS_OP_RUONLY (IC_RIGHT (ic)) &&
3139 getSize (aggrToPtr (operandType (IC_RESULT (ic)), FALSE)) > 1)
3140 packRegsForOneuse (ic, IC_RESULT (ic), ebp);
3142 /* if pointer get */
3143 if (POINTER_GET (ic) &&
3144 IS_SYMOP (IC_LEFT (ic)) &&
3145 !isOperandInFarSpace (IC_RESULT (ic)) &&
3146 !OP_SYMBOL (IC_LEFT (ic))->remat &&
3147 !IS_OP_RUONLY (IC_RESULT (ic)) &&
3148 getSize (aggrToPtr (operandType (IC_LEFT (ic)), FALSE)) > 1)
3149 packRegsForOneuse (ic, IC_LEFT (ic), ebp);
3151 /* if this is a cast for intergral promotion then
3152 check if it's the only use of the definition of the
3153 operand being casted/ if yes then replace
3154 the result of that arithmetic operation with
3155 this result and get rid of the cast */
3158 sym_link *fromType = operandType (IC_RIGHT (ic));
3159 sym_link *toType = operandType (IC_LEFT (ic));
3161 if (IS_INTEGRAL (fromType) && IS_INTEGRAL (toType) &&
3162 getSize (fromType) != getSize (toType) &&
3163 SPEC_USIGN (fromType) == SPEC_USIGN (toType))
3166 iCode *dic = packRegsForOneuse (ic, IC_RIGHT (ic), ebp);
3169 if (IS_ARITHMETIC_OP (dic))
3171 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
3172 ReplaceOpWithCheaperOp(&IC_RESULT (dic), IC_RESULT (ic));
3173 remiCodeFromeBBlock (ebp, ic);
3174 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
3175 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
3176 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
3180 OP_SYMBOL (IC_RIGHT (ic))->ruonly = 0;
3185 /* if the type from and type to are the same
3186 then if this is the only use then packit */
3187 if (compareType (operandType (IC_RIGHT (ic)),
3188 operandType (IC_LEFT (ic))) == 1)
3190 iCode *dic = packRegsForOneuse (ic, IC_RIGHT (ic), ebp);
3193 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
3194 ReplaceOpWithCheaperOp(&IC_RESULT (dic), IC_RESULT (ic));
3195 remiCodeFromeBBlock (ebp, ic);
3196 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
3197 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
3198 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
3206 iTempNN := (some variable in farspace) V1
3211 if (ic->op == IPUSH)
3213 packForPush (ic, ebpp, blockno);
3217 /* pack registers for accumulator use, when the
3218 result of an arithmetic or bit wise operation
3219 has only one use, that use is immediately following
3220 the defintion and the using iCode has only one
3221 operand or has two operands but one is literal &
3222 the result of that operation is not on stack then
3223 we can leave the result of this operation in acc:b
3225 if ((IS_ARITHMETIC_OP (ic)
3226 || IS_CONDITIONAL(ic)
3227 || IS_BITWISE_OP (ic)
3228 || ic->op == LEFT_OP || ic->op == RIGHT_OP || ic->op == CALL
3229 || (ic->op == ADDRESS_OF && isOperandOnStack (IC_LEFT (ic)))
3231 IS_ITEMP (IC_RESULT (ic)) &&
3232 getSize (operandType (IC_RESULT (ic))) <= 2)
3234 packRegsForAccUse (ic);
3238 /*-----------------------------------------------------------------*/
3239 /* assignRegisters - assigns registers to each live range as need */
3240 /*-----------------------------------------------------------------*/
3242 mcs51_assignRegisters (ebbIndex * ebbi)
3244 eBBlock ** ebbs = ebbi->bbOrder;
3245 int count = ebbi->count;
3249 setToNull ((void *) &_G.funcrUsed);
3250 setToNull ((void *) &_G.regAssigned);
3251 setToNull ((void *) &_G.totRegAssigned);
3252 mcs51_ptrRegReq = _G.stackExtend = _G.dataExtend = 0;
3253 if ((currFunc && IFFUNC_ISREENT (currFunc->type)) || options.stackAuto)
3261 _G.allBitregs = findAllBitregs ();
3264 /* change assignments this will remove some
3265 live ranges reducing some register pressure */
3267 for (i = 0; i < count; i++)
3268 packRegisters (ebbs, i);
3270 /* liveranges probably changed by register packing
3271 so we compute them again */
3272 recomputeLiveRanges (ebbs, count);
3274 if (options.dump_pack)
3275 dumpEbbsToFileExt (DUMP_PACK, ebbi);
3277 /* first determine for each live range the number of
3278 registers & the type of registers required for each */
3281 /* and serially allocate registers */
3282 serialRegAssign (ebbs, count);
3285 //setToNull ((void *) &_G.regAssigned);
3286 //setToNull ((void *) &_G.totRegAssigned);
3289 /* if stack was extended then tell the user */
3292 /* werror(W_TOOMANY_SPILS,"stack", */
3293 /* _G.stackExtend,currFunc->name,""); */
3299 /* werror(W_TOOMANY_SPILS,"data space", */
3300 /* _G.dataExtend,currFunc->name,""); */
3304 /* after that create the register mask
3305 for each of the instruction */
3306 createRegMask (ebbs, count);
3308 /* redo that offsets for stacked automatic variables */
3310 redoStackOffsets ();
3313 /* make sure r0 & r1 are flagged as used if they might be used */
3315 if (currFunc && mcs51_ptrRegReq)
3317 currFunc->regsUsed = bitVectSetBit (currFunc->regsUsed, R0_IDX);
3318 currFunc->regsUsed = bitVectSetBit (currFunc->regsUsed, R1_IDX);
3321 if (options.dump_rassgn)
3323 dumpEbbsToFileExt (DUMP_RASSGN, ebbi);
3324 dumpLiveRanges (DUMP_LRANGE, liveRanges);
3327 /* do the overlaysegment stuff SDCCmem.c */
3328 doOverlays (ebbs, count);
3330 /* now get back the chain */
3331 ic = iCodeLabelOptimize (iCodeFromeBBlock (ebbs, count));
3335 /* free up any _G.stackSpil locations allocated */
3336 applyToSet (_G.stackSpil, deallocStackSpil);
3338 setToNull ((void *) &_G.stackSpil);
3339 setToNull ((void *) &_G.spiltSet);
3340 /* mark all registers as free */