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 /*-----------------------------------------------------------------*/
47 bitVect *totRegAssigned; /* final set of LRs that got into registers */
50 bitVect *funcrUsed; /* registers used in a function */
56 /* Shared with gen.c */
57 int ds390_ptrRegReq; /* one byte pointer register required */
63 {REG_GPR, R2_IDX, REG_GPR, "r2", "ar2", "0", 2, 1, 1},
64 {REG_GPR, R3_IDX, REG_GPR, "r3", "ar3", "0", 3, 1, 1},
65 {REG_GPR, R4_IDX, REG_GPR, "r4", "ar4", "0", 4, 1, 1},
66 {REG_GPR, R5_IDX, REG_GPR, "r5", "ar5", "0", 5, 1, 1},
67 {REG_GPR, R6_IDX, REG_GPR, "r6", "ar6", "0", 6, 1, 1},
68 {REG_GPR, R7_IDX, REG_GPR, "r7", "ar7", "0", 7, 1, 1},
69 {REG_PTR, R0_IDX, REG_PTR, "r0", "ar0", "0", 0, 1, 1},
70 {REG_PTR, R1_IDX, REG_PTR, "r1", "ar1", "0", 1, 1, 1},
71 {REG_GPR, DPL_IDX, REG_GPR, "dpl", "dpl", "dpl", 0, 0, 0},
72 {REG_GPR, DPH_IDX, REG_GPR, "dph", "dph", "dph", 0, 0, 0},
73 {REG_GPR, DPX_IDX, REG_GPR, "dpx", "dpx", "dpx", 0, 0, 0},
74 {REG_GPR, B_IDX, REG_GPR, "b", "b", "b", 0, 0, 0},
75 {REG_GPR, X8_IDX, REG_GPR, "x8", "x8", "xreg", 0, 0, 0},
76 {REG_GPR, X9_IDX, REG_GPR, "x9", "x9", "xreg", 1, 0, 0},
77 {REG_GPR, X10_IDX, REG_GPR, "x10", "x10", "xreg", 2, 0, 0},
78 {REG_GPR, X11_IDX, REG_GPR, "x11", "x11", "xreg", 3, 0, 0},
79 {REG_GPR, X12_IDX, REG_GPR, "x12", "x12", "xreg", 4, 0, 0},
80 {REG_CND, CND_IDX, REG_GPR, "C", "psw", "xreg", 0, 0, 0},
81 {0, DPL1_IDX, 0, "dpl1", "dpl1", "dpl1", 0, 0, 0},
82 {0, DPH1_IDX, 0, "dph1", "dph1", "dph1", 0, 0, 0},
83 {0, DPX1_IDX, 0, "dpx1", "dpx1", "dpx1", 0, 0, 0},
84 {0, DPS_IDX, 0, "dps", "dps", "dps", 0, 0, 0},
85 {0, A_IDX, 0, "a", "acc", "acc", 0, 0, 0},
86 {0, AP_IDX, 0, "ap", "ap", "ap", 0, 0, 0},
89 static void spillThis (symbol *);
90 static void freeAllRegs ();
91 static iCode * packRegsDPTRuse (operand *);
92 static int packRegsDPTRnuse (operand *,int);
94 /*-----------------------------------------------------------------*/
95 /* allocReg - allocates register of given type */
96 /*-----------------------------------------------------------------*/
102 for (i = 0; i < ds390_nRegs; i++)
105 /* if type is given as 0 then any
106 free register will do */
110 regs390[i].isFree = 0;
113 bitVectSetBit (currFunc->regsUsed, i);
116 /* other wise look for specific type
118 if (regs390[i].isFree &&
119 regs390[i].type == type)
121 regs390[i].isFree = 0;
124 bitVectSetBit (currFunc->regsUsed, i);
131 /*-----------------------------------------------------------------*/
132 /* ds390_regWithIdx - returns pointer to register wit index number */
133 /*-----------------------------------------------------------------*/
135 ds390_regWithIdx (int idx)
139 for (i = 0; i < sizeof(regs390)/sizeof(regs); i++)
140 if (regs390[i].rIdx == idx)
143 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
144 "regWithIdx not found");
148 /*-----------------------------------------------------------------*/
149 /* freeReg - frees a register */
150 /*-----------------------------------------------------------------*/
157 /*-----------------------------------------------------------------*/
158 /* useReg - marks a register as used */
159 /*-----------------------------------------------------------------*/
167 /*-----------------------------------------------------------------*/
168 /* nFreeRegs - returns number of free registers */
169 /*-----------------------------------------------------------------*/
176 for (i = 0; i < ds390_nRegs; i++)
177 if (regs390[i].isFree && regs390[i].type == type)
182 /*-----------------------------------------------------------------*/
183 /* nfreeRegsType - free registers with type */
184 /*-----------------------------------------------------------------*/
186 nfreeRegsType (int type)
191 if ((nfr = nFreeRegs (type)) == 0)
192 return nFreeRegs (REG_GPR);
195 return nFreeRegs (type);
200 /*-----------------------------------------------------------------*/
201 /* isOperandInReg - returns true if operand is currently in regs */
202 /*-----------------------------------------------------------------*/
203 static int isOperandInReg(operand *op)
205 if (!IS_SYMOP(op)) return 0;
206 if (OP_SYMBOL(op)->ruonly) return 1;
207 if (OP_SYMBOL(op)->accuse) return 1;
208 if (OP_SYMBOL(op)->dptr) return 1;
209 return bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(op)->key);
212 /*-----------------------------------------------------------------*/
213 /* computeSpillable - given a point find the spillable live ranges */
214 /*-----------------------------------------------------------------*/
216 computeSpillable (iCode * ic)
220 /* spillable live ranges are those that are live at this
221 point . the following categories need to be subtracted
223 a) - those that are already spilt
224 b) - if being used by this one
225 c) - defined by this one */
227 spillable = bitVectCopy (ic->rlive);
229 bitVectCplAnd (spillable, _G.spiltSet); /* those already spilt */
231 bitVectCplAnd (spillable, ic->uses); /* used in this one */
232 bitVectUnSetBit (spillable, ic->defKey);
233 spillable = bitVectIntersect (spillable, _G.regAssigned);
238 /*-----------------------------------------------------------------*/
239 /* noSpilLoc - return true if a variable has no spil location */
240 /*-----------------------------------------------------------------*/
242 noSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
244 return (sym->usl.spillLoc ? 0 : 1);
247 /*-----------------------------------------------------------------*/
248 /* hasSpilLoc - will return 1 if the symbol has spil location */
249 /*-----------------------------------------------------------------*/
251 hasSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
253 return (sym->usl.spillLoc ? 1 : 0);
256 /*-----------------------------------------------------------------*/
257 /* directSpilLoc - will return 1 if the splilocation is in direct */
258 /*-----------------------------------------------------------------*/
260 directSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
262 if (sym->usl.spillLoc &&
263 (IN_DIRSPACE (SPEC_OCLS (sym->usl.spillLoc->etype))))
269 /*-----------------------------------------------------------------*/
270 /* hasSpilLocnoUptr - will return 1 if the symbol has spil location */
271 /* but is not used as a pointer */
272 /*-----------------------------------------------------------------*/
274 hasSpilLocnoUptr (symbol * sym, eBBlock * ebp, iCode * ic)
276 return ((sym->usl.spillLoc && !sym->uptr) ? 1 : 0);
279 /*-----------------------------------------------------------------*/
280 /* rematable - will return 1 if the remat flag is set */
281 /*-----------------------------------------------------------------*/
283 rematable (symbol * sym, eBBlock * ebp, iCode * ic)
288 /*-----------------------------------------------------------------*/
289 /* notUsedInRemaining - not used or defined in remain of the block */
290 /*-----------------------------------------------------------------*/
292 notUsedInRemaining (symbol * sym, eBBlock * ebp, iCode * ic)
294 return ((usedInRemaining (operandFromSymbol (sym), ic) ? 0 : 1) &&
295 allDefsOutOfRange (sym->defs, ebp->fSeq, ebp->lSeq));
298 /*-----------------------------------------------------------------*/
299 /* allLRs - return true for all */
300 /*-----------------------------------------------------------------*/
302 allLRs (symbol * sym, eBBlock * ebp, iCode * ic)
307 /*-----------------------------------------------------------------*/
308 /* liveRangesWith - applies function to a given set of live range */
309 /*-----------------------------------------------------------------*/
311 liveRangesWith (bitVect * lrs, int (func) (symbol *, eBBlock *, iCode *),
312 eBBlock * ebp, iCode * ic)
317 if (!lrs || !lrs->size)
320 for (i = 1; i < lrs->size; i++)
323 if (!bitVectBitValue (lrs, i))
326 /* if we don't find it in the live range
327 hash table we are in serious trouble */
328 if (!(sym = hTabItemWithKey (liveRanges, i)))
330 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
331 "liveRangesWith could not find liveRange");
335 if (func (sym, ebp, ic) && bitVectBitValue (_G.regAssigned, sym->key))
336 addSetHead (&rset, sym);
343 /*-----------------------------------------------------------------*/
344 /* leastUsedLR - given a set determines which is the least used */
345 /*-----------------------------------------------------------------*/
347 leastUsedLR (set * sset)
349 symbol *sym = NULL, *lsym = NULL;
351 sym = lsym = setFirstItem (sset);
356 for (; lsym; lsym = setNextItem (sset))
359 /* if usage is the same then prefer
360 the spill the smaller of the two */
361 if (lsym->used == sym->used)
362 if (getSize (lsym->type) < getSize (sym->type))
366 if (lsym->used < sym->used)
371 setToNull ((void *) &sset);
376 /*-----------------------------------------------------------------*/
377 /* noOverLap - will iterate through the list looking for over lap */
378 /*-----------------------------------------------------------------*/
380 noOverLap (set * itmpStack, symbol * fsym)
384 for (sym = setFirstItem (itmpStack); sym;
385 sym = setNextItem (itmpStack))
387 if (bitVectBitValue(sym->clashes,fsym->key)) return 0;
392 /*-----------------------------------------------------------------*/
393 /* isFree - will return 1 if the a free spil location is found */
394 /*-----------------------------------------------------------------*/
399 V_ARG (symbol **, sloc);
400 V_ARG (symbol *, fsym);
402 /* if already found */
406 /* if it is free && and the itmp assigned to
407 this does not have any overlapping live ranges
408 with the one currently being assigned and
409 the size can be accomodated */
411 noOverLap (sym->usl.itmpStack, fsym) &&
412 getSize (sym->type) >= getSize (fsym->type))
421 /*-----------------------------------------------------------------*/
422 /* spillLRWithPtrReg :- will spil those live ranges which use PTR */
423 /*-----------------------------------------------------------------*/
425 spillLRWithPtrReg (symbol * forSym)
431 if (!_G.regAssigned ||
432 bitVectIsZero (_G.regAssigned))
435 r0 = ds390_regWithIdx (R0_IDX);
436 r1 = ds390_regWithIdx (R1_IDX);
438 /* for all live ranges */
439 for (lrsym = hTabFirstItem (liveRanges, &k); lrsym;
440 lrsym = hTabNextItem (liveRanges, &k))
444 /* if no registers assigned to it or
446 /* if it does not overlap with this then
447 not need to spill it */
449 if (lrsym->isspilt || !lrsym->nRegs ||
450 (lrsym->liveTo < forSym->liveFrom))
453 /* go thru the registers : if it is either
454 r0 or r1 then spil it */
455 for (j = 0; j < lrsym->nRegs; j++)
456 if (lrsym->regs[j] == r0 ||
457 lrsym->regs[j] == r1)
466 /*-----------------------------------------------------------------*/
467 /* createStackSpil - create a location on the stack to spil */
468 /*-----------------------------------------------------------------*/
470 createStackSpil (symbol * sym)
473 int useXstack, model, noOverlay;
477 /* first go try and find a free one that is already
478 existing on the stack */
479 if (applyToSet (_G.stackSpil, isFree, &sloc, sym))
481 /* found a free one : just update & return */
482 sym->usl.spillLoc = sloc;
485 addSetHead (&sloc->usl.itmpStack, sym);
489 /* could not then have to create one , this is the hard part
490 we need to allocate this on the stack : this is really a
491 hack!! but cannot think of anything better at this time */
493 if (SNPRINTF (slocBuffer, sizeof(slocBuffer),
494 "sloc%d", _G.slocNum++) >= sizeof (slocBuffer))
496 fprintf (stderr, "***Internal error: slocBuffer overflowed: %s:%d\n",
501 sloc = newiTemp (slocBuffer);
503 /* set the type to the spilling symbol */
504 sloc->type = copyLinkChain (sym->type);
505 sloc->etype = getSpec (sloc->type);
506 if (options.model == MODEL_SMALL) {
507 SPEC_SCLS (sloc->etype) = S_DATA;
509 SPEC_SCLS (sloc->etype) = S_XDATA;
511 SPEC_EXTR (sloc->etype) = 0;
512 SPEC_STAT (sloc->etype) = 0;
513 SPEC_VOLATILE(sloc->etype) = 0;
514 SPEC_ABSA(sloc->etype) = 0;
516 /* we don't allow it to be allocated`
517 onto the external stack since : so we
518 temporarily turn it off ; we also
519 turn off memory model to prevent
520 the spil from going to the external storage
521 and turn off overlaying
524 useXstack = options.useXstack;
525 model = options.model;
526 noOverlay = options.noOverlay;
527 options.noOverlay = 1;
529 /* options.model = options.useXstack = 0; */
533 options.useXstack = useXstack;
534 options.model = model;
535 options.noOverlay = noOverlay;
536 sloc->isref = 1; /* to prevent compiler warning */
538 /* if it is on the stack then update the stack */
539 if (IN_STACK (sloc->etype))
541 currFunc->stack += getSize (sloc->type);
542 _G.stackExtend += getSize (sloc->type);
545 _G.dataExtend += getSize (sloc->type);
547 /* add it to the _G.stackSpil set */
548 addSetHead (&_G.stackSpil, sloc);
549 sym->usl.spillLoc = sloc;
552 /* add it to the set of itempStack set
553 of the spill location */
554 addSetHead (&sloc->usl.itmpStack, sym);
558 /*-----------------------------------------------------------------*/
559 /* isSpiltOnStack - returns true if the spil location is on stack */
560 /*-----------------------------------------------------------------*/
562 isSpiltOnStack (symbol * sym)
572 /* if (sym->_G.stackSpil) */
575 if (!sym->usl.spillLoc)
578 etype = getSpec (sym->usl.spillLoc->type);
579 if (IN_STACK (etype))
585 /*-----------------------------------------------------------------*/
586 /* spillThis - spils a specific operand */
587 /*-----------------------------------------------------------------*/
589 spillThis (symbol * sym)
592 /* if this is rematerializable or has a spillLocation
593 we are okay, else we need to create a spillLocation
595 if (!(sym->remat || sym->usl.spillLoc))
596 createStackSpil (sym);
599 /* mark it has spilt & put it in the spilt set */
600 sym->isspilt = sym->spillA = 1;
601 _G.spiltSet = bitVectSetBit (_G.spiltSet, sym->key);
603 bitVectUnSetBit (_G.regAssigned, sym->key);
604 bitVectUnSetBit (_G.totRegAssigned, sym->key);
606 for (i = 0; i < sym->nRegs; i++)
610 freeReg (sym->regs[i]);
614 /* if spilt on stack then free up r0 & r1
615 if they could have been assigned to some
617 if (!ds390_ptrRegReq && isSpiltOnStack (sym) && !options.stack10bit)
620 spillLRWithPtrReg (sym);
623 if (sym->usl.spillLoc && !sym->remat)
624 sym->usl.spillLoc->allocreq++;
628 /*-----------------------------------------------------------------*/
629 /* selectSpil - select a iTemp to spil : rather a simple procedure */
630 /*-----------------------------------------------------------------*/
632 selectSpil (iCode * ic, eBBlock * ebp, symbol * forSym)
634 bitVect *lrcs = NULL;
638 /* get the spillable live ranges */
639 lrcs = computeSpillable (ic);
641 /* get all live ranges that are rematerizable */
642 if ((selectS = liveRangesWith (lrcs, rematable, ebp, ic)))
645 /* return the least used of these */
646 return leastUsedLR (selectS);
649 /* get live ranges with spillLocations in direct space */
650 if ((selectS = liveRangesWith (lrcs, directSpilLoc, ebp, ic)))
652 sym = leastUsedLR (selectS);
653 strncpyz (sym->rname,
654 sym->usl.spillLoc->rname[0] ?
655 sym->usl.spillLoc->rname : sym->usl.spillLoc->name,
658 /* mark it as allocation required */
659 sym->usl.spillLoc->allocreq++;
663 /* if the symbol is local to the block then */
664 if (forSym->liveTo < ebp->lSeq)
667 /* check if there are any live ranges allocated
668 to registers that are not used in this block */
669 if (!_G.blockSpil && (selectS = liveRangesWith (lrcs, notUsedInBlock, ebp, ic)))
671 sym = leastUsedLR (selectS);
672 /* if this is not rematerializable */
681 /* check if there are any live ranges that not
682 used in the remainder of the block */
683 if (!_G.blockSpil && (selectS = liveRangesWith (lrcs, notUsedInRemaining, ebp, ic)))
685 sym = leastUsedLR (selectS);
698 /* find live ranges with spillocation && not used as pointers */
699 if ((selectS = liveRangesWith (lrcs, hasSpilLocnoUptr, ebp, ic)))
702 sym = leastUsedLR (selectS);
703 /* mark this as allocation required */
704 sym->usl.spillLoc->allocreq++;
708 /* find live ranges with spillocation */
709 if ((selectS = liveRangesWith (lrcs, hasSpilLoc, ebp, ic)))
712 sym = leastUsedLR (selectS);
713 sym->usl.spillLoc->allocreq++;
717 /* couldn't find then we need to create a spil
718 location on the stack , for which one? the least
720 if ((selectS = liveRangesWith (lrcs, noSpilLoc, ebp, ic)))
723 /* return a created spil location */
724 sym = createStackSpil (leastUsedLR (selectS));
725 sym->usl.spillLoc->allocreq++;
729 /* this is an extreme situation we will spill
730 this one : happens very rarely but it does happen */
736 /*-----------------------------------------------------------------*/
737 /* spilSomething - spil some variable & mark registers as free */
738 /*-----------------------------------------------------------------*/
740 spilSomething (iCode * ic, eBBlock * ebp, symbol * forSym)
745 /* get something we can spil */
746 ssym = selectSpil (ic, ebp, forSym);
748 /* mark it as spilt */
749 ssym->isspilt = ssym->spillA = 1;
750 _G.spiltSet = bitVectSetBit (_G.spiltSet, ssym->key);
752 /* mark it as not register assigned &
753 take it away from the set */
754 bitVectUnSetBit (_G.regAssigned, ssym->key);
755 bitVectUnSetBit (_G.totRegAssigned, ssym->key);
757 /* mark the registers as free */
758 for (i = 0; i < ssym->nRegs; i++)
760 freeReg (ssym->regs[i]);
762 /* if spilt on stack then free up r0 & r1
763 if they could have been assigned to as gprs */
764 if (!ds390_ptrRegReq && isSpiltOnStack (ssym) && !options.stack10bit)
767 spillLRWithPtrReg (ssym);
770 /* if this was a block level spil then insert push & pop
771 at the start & end of block respectively */
774 iCode *nic = newiCode (IPUSH, operandFromSymbol (ssym), NULL);
775 /* add push to the start of the block */
776 addiCodeToeBBlock (ebp, nic, (ebp->sch->op == LABEL ?
777 ebp->sch->next : ebp->sch));
778 nic = newiCode (IPOP, operandFromSymbol (ssym), NULL);
779 /* add pop to the end of the block */
780 addiCodeToeBBlock (ebp, nic, NULL);
783 /* if spilt because not used in the remainder of the
784 block then add a push before this instruction and
785 a pop at the end of the block */
786 if (ssym->remainSpil)
789 iCode *nic = newiCode (IPUSH, operandFromSymbol (ssym), NULL);
790 /* add push just before this instruction */
791 addiCodeToeBBlock (ebp, nic, ic);
793 nic = newiCode (IPOP, operandFromSymbol (ssym), NULL);
794 /* add pop to the end of the block */
795 addiCodeToeBBlock (ebp, nic, NULL);
804 /*-----------------------------------------------------------------*/
805 /* getRegPtr - will try for PTR if not a GPR type if not spil */
806 /*-----------------------------------------------------------------*/
808 getRegPtr (iCode * ic, eBBlock * ebp, symbol * sym)
814 /* try for a ptr type */
815 if ((reg = allocReg (REG_PTR)))
818 /* try for gpr type */
819 if ((reg = allocReg (REG_GPR)))
822 /* we have to spil */
823 if (!spilSomething (ic, ebp, sym))
826 /* make sure partially assigned registers aren't reused */
827 for (j=0; j<=sym->nRegs; j++)
829 sym->regs[j]->isFree = 0;
831 /* this looks like an infinite loop but
832 in really selectSpil will abort */
836 /*-----------------------------------------------------------------*/
837 /* getRegGpr - will try for GPR if not spil */
838 /*-----------------------------------------------------------------*/
840 getRegGpr (iCode * ic, eBBlock * ebp, symbol * sym)
846 /* try for gpr type */
847 if ((reg = allocReg (REG_GPR)))
850 if (!ds390_ptrRegReq)
851 if ((reg = allocReg (REG_PTR)))
854 /* we have to spil */
855 if (!spilSomething (ic, ebp, sym))
858 /* make sure partially assigned registers aren't reused */
859 for (j=0; j<=sym->nRegs; j++)
861 sym->regs[j]->isFree = 0;
863 /* this looks like an infinite loop but
864 in really selectSpil will abort */
868 /*-----------------------------------------------------------------*/
869 /* getRegPtrNoSpil - get it cannot split */
870 /*-----------------------------------------------------------------*/
871 static regs *getRegPtrNoSpil()
875 /* try for a ptr type */
876 if ((reg = allocReg (REG_PTR)))
879 /* try for gpr type */
880 if ((reg = allocReg (REG_GPR)))
885 /* just to make the compiler happy */
889 /*-----------------------------------------------------------------*/
890 /* getRegGprNoSpil - get it cannot split */
891 /*-----------------------------------------------------------------*/
892 static regs *getRegGprNoSpil()
896 if ((reg = allocReg (REG_GPR)))
899 if (!ds390_ptrRegReq)
900 if ((reg = allocReg (REG_PTR)))
905 /* just to make the compiler happy */
909 /*-----------------------------------------------------------------*/
910 /* symHasReg - symbol has a given register */
911 /*-----------------------------------------------------------------*/
913 symHasReg (symbol * sym, regs * reg)
917 for (i = 0; i < sym->nRegs; i++)
918 if (sym->regs[i] == reg)
924 /*-----------------------------------------------------------------*/
925 /* deassignLRs - check the live to and if they have registers & are */
926 /* not spilt then free up the registers */
927 /*-----------------------------------------------------------------*/
929 deassignLRs (iCode * ic, eBBlock * ebp)
935 for (sym = hTabFirstItem (liveRanges, &k); sym;
936 sym = hTabNextItem (liveRanges, &k))
940 /* if it does not end here */
941 if (sym->liveTo > ic->seq)
944 /* if it was spilt on stack then we can
945 mark the stack spil location as free */
950 sym->usl.spillLoc->isFree = 1;
956 if (!bitVectBitValue (_G.regAssigned, sym->key))
959 /* special case check if this is an IFX &
960 the privious one was a pop and the
961 previous one was not spilt then keep track
963 if (ic->op == IFX && ic->prev &&
964 ic->prev->op == IPOP &&
965 !ic->prev->parmPush &&
966 !OP_SYMBOL (IC_LEFT (ic->prev))->isspilt)
967 psym = OP_SYMBOL (IC_LEFT (ic->prev));
973 bitVectUnSetBit (_G.regAssigned, sym->key);
975 /* if the result of this one needs registers
976 and does not have it then assign it right
978 if (IC_RESULT (ic) &&
979 !(SKIP_IC2 (ic) || /* not a special icode */
980 ic->op == JUMPTABLE ||
986 (result = OP_SYMBOL (IC_RESULT (ic))) && /* has a result */
987 result->liveTo > ic->seq && /* and will live beyond this */
988 result->liveTo <= ebp->lSeq && /* does not go beyond this block */
989 result->regType == sym->regType && /* same register types */
990 result->nRegs && /* which needs registers */
991 !result->isspilt && /* and does not already have them */
993 !bitVectBitValue (_G.regAssigned, result->key) &&
994 /* the number of free regs + number of regs in this LR
995 can accomodate the what result Needs */
996 ((nfreeRegsType (result->regType) +
997 sym->nRegs) >= result->nRegs)
1001 for (i = 0; i < result->nRegs; i++)
1003 result->regs[i] = sym->regs[i];
1005 result->regs[i] = getRegGpr (ic, ebp, result);
1007 _G.regAssigned = bitVectSetBit (_G.regAssigned, result->key);
1008 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, result->key);
1012 /* free the remaining */
1013 for (; i < sym->nRegs; i++)
1017 if (!symHasReg (psym, sym->regs[i]))
1018 freeReg (sym->regs[i]);
1021 freeReg (sym->regs[i]);
1028 /*-----------------------------------------------------------------*/
1029 /* reassignLR - reassign this to registers */
1030 /*-----------------------------------------------------------------*/
1032 reassignLR (operand * op)
1034 symbol *sym = OP_SYMBOL (op);
1037 /* not spilt any more */
1038 sym->isspilt = sym->spillA = sym->blockSpil = sym->remainSpil = 0;
1039 bitVectUnSetBit (_G.spiltSet, sym->key);
1041 _G.regAssigned = bitVectSetBit (_G.regAssigned, sym->key);
1042 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, sym->key);
1046 for (i = 0; i < sym->nRegs; i++)
1047 sym->regs[i]->isFree = 0;
1050 /*-----------------------------------------------------------------*/
1051 /* willCauseSpill - determines if allocating will cause a spill */
1052 /*-----------------------------------------------------------------*/
1054 willCauseSpill (int nr, int rt)
1056 /* first check if there are any avlb registers
1057 of te type required */
1060 /* special case for pointer type
1061 if pointer type not avlb then
1062 check for type gpr */
1063 if (nFreeRegs (rt) >= nr)
1065 if (nFreeRegs (REG_GPR) >= nr)
1070 if (ds390_ptrRegReq)
1072 if (nFreeRegs (rt) >= nr)
1077 if (nFreeRegs (REG_PTR) +
1078 nFreeRegs (REG_GPR) >= nr)
1083 /* it will cause a spil */
1087 /*-----------------------------------------------------------------*/
1088 /* positionRegs - the allocator can allocate same registers to res- */
1089 /* ult and operand, if this happens make sure they are in the same */
1090 /* position as the operand otherwise chaos results */
1091 /*-----------------------------------------------------------------*/
1093 positionRegs (symbol * result, symbol * opsym)
1095 int count = min (result->nRegs, opsym->nRegs);
1096 int i, j = 0, shared = 0;
1099 /* if the result has been spilt then cannot share */
1104 /* first make sure that they actually share */
1105 for (i = 0; i < count; i++)
1107 for (j = 0; j < count; j++)
1109 if (result->regs[i] == opsym->regs[j] && i != j)
1119 regs *tmp = result->regs[i];
1120 result->regs[i] = result->regs[j];
1121 result->regs[j] = tmp;
1128 /*-----------------------------------------------------------------*/
1129 /* unusedLRS - returns a bitVector of liveranges not used in 'ebp' */
1130 /*-----------------------------------------------------------------*/
1131 bitVect *unusedLRs (eBBlock *ebp)
1133 bitVect *ret = NULL;
1137 if (!ebp) return NULL;
1138 for (sym = hTabFirstItem(liveRanges,&key); sym ;
1139 sym = hTabNextItem(liveRanges,&key)) {
1141 if (notUsedInBlock(sym,ebp,NULL)) {
1142 ret = bitVectSetBit(ret,sym->key);
1149 /*-----------------------------------------------------------------*/
1150 /* deassignUnsedLRs - if this baisc block ends in a return then */
1151 /* deassign symbols not used in this block */
1152 /*-----------------------------------------------------------------*/
1153 bitVect *deassignUnsedLRs(eBBlock *ebp)
1155 bitVect *unused = NULL;
1158 switch (returnAtEnd(ebp)) {
1159 case 2: /* successor block ends in a return */
1160 unused = unusedLRs((eBBlock *) setFirstItem(ebp->succList));
1162 case 1: /* this block ends in a return */
1163 unused = bitVectIntersect(unused,unusedLRs(ebp));
1168 for (i = 0 ; i < unused->size ; i++ ) {
1171 if (bitVectBitValue(unused,i)) {
1173 /* if assigned to registers */
1174 if (bitVectBitValue(_G.regAssigned,i)) {
1178 sym = hTabItemWithKey(liveRanges,i);
1179 /* remove it from regassigned & mark the
1181 bitVectUnSetBit(_G.regAssigned,i);
1182 for (j = 0 ; j < sym->nRegs; j++)
1183 freeReg(sym->regs[j]);
1185 /* not assigned to registers : remove from set*/
1186 bitVectUnSetBit(unused,i);
1194 /*-----------------------------------------------------------------*/
1195 /* reassignUnusedLRs - put registers to unused Live ranges */
1196 /*-----------------------------------------------------------------*/
1197 void reassignUnusedLRs (bitVect *unused)
1200 if (!unused) return ;
1202 for (i = 0 ; i < unused->size ; i++ ) {
1203 /* if unused : means it was assigned to registers before */
1204 if (bitVectBitValue(unused,i)) {
1208 /* put it back into reg set*/
1209 bitVectSetBit(_G.regAssigned,i) ;
1211 sym = hTabItemWithKey(liveRanges,i);
1212 /* makr registers busy */
1213 for (j = 0 ; j < sym->nRegs; j++)
1214 sym->regs[j]->isFree = 0;
1219 /*------------------------------------------------------------------*/
1220 /* verifyRegsAssigned - make sure an iTemp is properly initialized; */
1221 /* it should either have registers or have beed spilled. Otherwise, */
1222 /* there was an uninitialized variable, so just spill this to get */
1223 /* the operand in a valid state. */
1224 /*------------------------------------------------------------------*/
1226 verifyRegsAssigned (operand *op, iCode * ic)
1231 if (!IS_ITEMP (op)) return;
1233 sym = OP_SYMBOL (op);
1234 if (sym->isspilt) return;
1235 if (!sym->nRegs) return;
1236 if (sym->regs[0]) return;
1238 werrorfl (ic->filename, ic->lineno, W_LOCAL_NOINIT,
1239 sym->prereqv ? sym->prereqv->name : sym->name);
1244 /*-----------------------------------------------------------------*/
1245 /* serialRegAssign - serially allocate registers to the variables */
1246 /*-----------------------------------------------------------------*/
1248 serialRegAssign (eBBlock ** ebbs, int count)
1252 /* for all blocks */
1253 for (i = 0; i < count; i++)
1257 bitVect *unusedLRs = NULL;
1259 if (ebbs[i]->noPath &&
1260 (ebbs[i]->entryLabel != entryLabel &&
1261 ebbs[i]->entryLabel != returnLabel))
1264 unusedLRs = deassignUnsedLRs(ebbs[i]);
1266 /* of all instructions do */
1267 for (ic = ebbs[i]->sch; ic; ic = ic->next)
1270 /* if this is an ipop that means some live
1271 range will have to be assigned again */
1273 reassignLR (IC_LEFT (ic));
1275 /* if result is present && is a true symbol */
1276 if (IC_RESULT (ic) && ic->op != IFX &&
1277 IS_TRUE_SYMOP (IC_RESULT (ic)))
1278 OP_SYMBOL (IC_RESULT (ic))->allocreq++;
1280 /* take away registers from live
1281 ranges that end at this instruction */
1282 deassignLRs (ic, ebbs[i]);
1284 /* some don't need registers */
1285 if (SKIP_IC2 (ic) ||
1286 ic->op == JUMPTABLE ||
1290 (IC_RESULT (ic) && POINTER_SET (ic)))
1293 /* now we need to allocate registers
1294 only for the result */
1297 symbol *sym = OP_SYMBOL (IC_RESULT (ic));
1303 /* if it does not need or is spilt
1304 or is already assigned to registers
1305 or will not live beyond this instructions */
1308 bitVectBitValue (_G.regAssigned, sym->key) ||
1309 sym->liveTo <= ic->seq)
1312 /* if some liverange has been spilt at the block level
1313 and this one live beyond this block then spil this
1315 if (_G.blockSpil && sym->liveTo > ebbs[i]->lSeq)
1320 /* if trying to allocate this will cause
1321 a spill and there is nothing to spill
1322 or this one is rematerializable then
1324 willCS = willCauseSpill (sym->nRegs, sym->regType);
1325 spillable = computeSpillable (ic);
1327 (willCS && bitVectIsZero (spillable)))
1335 /* if it has a spillocation & is used less than
1336 all other live ranges then spill this */
1338 if (sym->usl.spillLoc) {
1339 symbol *leastUsed = leastUsedLR (liveRangesWith (spillable,
1340 allLRs, ebbs[i], ic));
1341 if (leastUsed && leastUsed->used > sym->used) {
1346 /* if none of the liveRanges have a spillLocation then better
1347 to spill this one than anything else already assigned to registers */
1348 if (liveRangesWith(spillable,noSpilLoc,ebbs[i],ic)) {
1349 /* if this is local to this block then we might find a block spil */
1350 if (!(sym->liveFrom >= ebbs[i]->fSeq && sym->liveTo <= ebbs[i]->lSeq)) {
1358 /* if we need ptr regs for the right side
1360 if (POINTER_GET (ic) && IS_SYMOP (IC_LEFT (ic))
1361 && getSize (OP_SYMBOL (IC_LEFT (ic))->type)
1362 <= (unsigned) PTRSIZE)
1367 /* else we assign registers to it */
1368 _G.regAssigned = bitVectSetBit (_G.regAssigned, sym->key);
1369 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, sym->key);
1371 for (j = 0; j < sym->nRegs; j++)
1373 if (sym->regType == REG_PTR)
1374 sym->regs[j] = getRegPtr (ic, ebbs[i], sym);
1376 sym->regs[j] = getRegGpr (ic, ebbs[i], sym);
1378 /* if the allocation falied which means
1379 this was spilt then break */
1384 /* if it shares registers with operands make sure
1385 that they are in the same position */
1386 if (!POINTER_SET(ic) && !POINTER_GET(ic))
1388 if (IC_LEFT (ic) && IS_SYMOP (IC_LEFT (ic)) &&
1389 OP_SYMBOL (IC_LEFT (ic))->nRegs)
1391 positionRegs (OP_SYMBOL (IC_RESULT (ic)),
1392 OP_SYMBOL (IC_LEFT (ic)));
1394 /* do the same for the right operand */
1395 if (IC_RIGHT (ic) && IS_SYMOP (IC_RIGHT (ic)) &&
1396 OP_SYMBOL (IC_RIGHT (ic))->nRegs)
1398 positionRegs (OP_SYMBOL (IC_RESULT (ic)),
1399 OP_SYMBOL (IC_RIGHT (ic)));
1411 reassignUnusedLRs(unusedLRs);
1414 /* Check for and fix any problems with uninitialized operands */
1415 for (i = 0; i < count; i++)
1419 if (ebbs[i]->noPath &&
1420 (ebbs[i]->entryLabel != entryLabel &&
1421 ebbs[i]->entryLabel != returnLabel))
1424 for (ic = ebbs[i]->sch; ic; ic = ic->next)
1431 verifyRegsAssigned (IC_COND (ic), ic);
1435 if (ic->op == JUMPTABLE)
1437 verifyRegsAssigned (IC_JTCOND (ic), ic);
1441 verifyRegsAssigned (IC_RESULT (ic), ic);
1442 verifyRegsAssigned (IC_LEFT (ic), ic);
1443 verifyRegsAssigned (IC_RIGHT (ic), ic);
1449 /*-----------------------------------------------------------------*/
1450 /* fillGaps - Try to fill in the Gaps left by Pass1 */
1451 /*-----------------------------------------------------------------*/
1452 static void fillGaps()
1456 int loop = 0, change;
1459 if (getenv("DISABLE_FILL_GAPS")) return;
1461 /* First try to do DPTRuse once more since now we know what got into
1464 while (loop++ < 10) {
1467 for (sym = hTabFirstItem(liveRanges,&key) ; sym ;
1468 sym = hTabNextItem(liveRanges,&key)) {
1469 int size = getSize(sym->type);
1471 if (sym->liveFrom == sym->liveTo) continue;
1473 if (sym->uptr && sym->dptr==0 && !sym->ruonly &&
1474 size < 4 && size > 1) {
1476 if (packRegsDPTRuse(operandFromSymbol(sym))) {
1478 /* if this was ssigned to registers then */
1479 if (bitVectBitValue(_G.totRegAssigned,sym->key)) {
1480 /* take it out of the register assigned set */
1481 bitVectUnSetBit(_G.totRegAssigned,sym->key);
1482 } else if (sym->usl.spillLoc) {
1483 sym->usl.spillLoc->allocreq--;
1484 sym->usl.spillLoc = NULL;
1488 sym->isspilt = sym->spillA = 0;
1492 /* try assigning other dptrs */
1493 if (sym->dptr == 0 && packRegsDPTRnuse(operandFromSymbol(sym),1) && !getenv("DPTRnDISABLE")) {
1494 /* if this was ssigned to registers then */
1495 if (bitVectBitValue(_G.totRegAssigned,sym->key)) {
1496 /* take it out of the register assigned set */
1497 bitVectUnSetBit(_G.totRegAssigned,sym->key);
1498 } else if (sym->usl.spillLoc) {
1499 sym->usl.spillLoc->allocreq--;
1500 sym->usl.spillLoc = NULL;
1503 sym->isspilt = sym->spillA = 0;
1508 /* look for livernages that was spilt by the allocator */
1509 for (sym = hTabFirstItem(liveRanges,&key) ; sym ;
1510 sym = hTabNextItem(liveRanges,&key)) {
1515 if (!sym->spillA || !sym->clashes || sym->remat) continue ;
1516 if (!sym->uses || !sym->defs) continue ;
1517 /* find the liveRanges this one clashes with, that are
1518 still assigned to registers & mark the registers as used*/
1519 for ( i = 0 ; i < sym->clashes->size ; i ++) {
1523 if (bitVectBitValue(sym->clashes,i) == 0 || /* those that clash with this */
1524 bitVectBitValue(_G.totRegAssigned,i) == 0) /* and are still assigned to registers */
1527 clr = hTabItemWithKey(liveRanges,i);
1530 /* mark these registers as used */
1531 for (k = 0 ; k < clr->nRegs ; k++ )
1532 useReg(clr->regs[k]);
1535 if (willCauseSpill(sym->nRegs,sym->regType)) {
1536 /* NOPE :( clear all registers & and continue */
1541 /* THERE IS HOPE !!!! */
1542 for (i=0; i < sym->nRegs ; i++ ) {
1543 if (sym->regType == REG_PTR)
1544 sym->regs[i] = getRegPtrNoSpil ();
1546 sym->regs[i] = getRegGprNoSpil ();
1549 /* For all its definitions check if the registers
1550 allocated needs positioning NOTE: we can position
1551 only ONCE if more than One positioning required
1553 We may need to perform the checks twice; once to
1554 position the registers as needed, the second to
1555 verify any register repositioning is still
1559 for (pass=0; pass<2; pass++) {
1560 for (i = 0 ; i < sym->defs->size ; i++ ) {
1561 if (bitVectBitValue(sym->defs,i)) {
1563 if (!(ic = hTabItemWithKey(iCodehTab,i))) continue ;
1564 if (SKIP_IC(ic)) continue;
1565 assert(isSymbolEqual(sym,OP_SYMBOL(IC_RESULT(ic)))); /* just making sure */
1566 /* if left is assigned to registers */
1567 if (IS_SYMOP(IC_LEFT(ic)) &&
1568 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_LEFT(ic))->key)) {
1569 pdone += (positionRegs(sym,OP_SYMBOL(IC_LEFT(ic)))>0);
1571 if (IS_SYMOP(IC_RIGHT(ic)) &&
1572 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_RIGHT(ic))->key)) {
1573 pdone += (positionRegs(sym,OP_SYMBOL(IC_RIGHT(ic)))>0);
1575 if (pdone > 1) break;
1578 for (i = 0 ; i < sym->uses->size ; i++ ) {
1579 if (bitVectBitValue(sym->uses,i)) {
1581 if (!(ic = hTabItemWithKey(iCodehTab,i))) continue ;
1582 if (SKIP_IC(ic)) continue;
1583 if (POINTER_SET(ic) || POINTER_GET(ic)) continue ;
1585 /* if result is assigned to registers */
1586 if (IS_SYMOP(IC_RESULT(ic)) &&
1587 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_RESULT(ic))->key)) {
1588 pdone += (positionRegs(sym,OP_SYMBOL(IC_RESULT(ic)))>0);
1590 if (pdone > 1) break;
1593 if (pdone == 0) break; /* second pass only if regs repositioned */
1594 if (pdone > 1) break;
1596 /* had to position more than once GIVE UP */
1598 /* UNDO all the changes we made to try this */
1600 for (i=0; i < sym->nRegs ; i++ ) {
1601 sym->regs[i] = NULL;
1604 D (fprintf (stderr, "Fill Gap gave up due to positioning for "
1605 "%s in function %s\n",
1606 sym->name, currFunc ? currFunc->name : "UNKNOWN"));
1609 D (fprintf (stderr, "FILLED GAP for %s in function %s\n",
1610 sym->name, currFunc ? currFunc->name : "UNKNOWN"));
1611 _G.totRegAssigned = bitVectSetBit(_G.totRegAssigned,sym->key);
1612 sym->isspilt = sym->spillA = 0 ;
1613 sym->usl.spillLoc->allocreq--;
1614 sym->usl.spillLoc = NULL;
1622 /*-----------------------------------------------------------------*/
1623 /* rUmaskForOp :- returns register mask for an operand */
1624 /*-----------------------------------------------------------------*/
1626 ds390_rUmaskForOp (operand * op)
1632 /* only temporaries are assigned registers */
1636 sym = OP_SYMBOL (op);
1638 /* if spilt or no registers assigned to it
1640 if (sym->isspilt || !sym->nRegs)
1643 rumask = newBitVect (ds390_nRegs);
1645 for (j = 0; j < sym->nRegs; j++)
1647 rumask = bitVectSetBit (rumask,
1648 sym->regs[j]->rIdx);
1654 /*-----------------------------------------------------------------*/
1655 /* regsUsedIniCode :- returns bit vector of registers used in iCode */
1656 /*-----------------------------------------------------------------*/
1658 regsUsedIniCode (iCode * ic)
1660 bitVect *rmask = newBitVect (ds390_nRegs);
1662 /* do the special cases first */
1665 rmask = bitVectUnion (rmask,
1666 ds390_rUmaskForOp (IC_COND (ic)));
1670 /* for the jumptable */
1671 if (ic->op == JUMPTABLE)
1673 rmask = bitVectUnion (rmask,
1674 ds390_rUmaskForOp (IC_JTCOND (ic)));
1679 /* of all other cases */
1681 rmask = bitVectUnion (rmask,
1682 ds390_rUmaskForOp (IC_LEFT (ic)));
1686 rmask = bitVectUnion (rmask,
1687 ds390_rUmaskForOp (IC_RIGHT (ic)));
1690 rmask = bitVectUnion (rmask,
1691 ds390_rUmaskForOp (IC_RESULT (ic)));
1697 /*-----------------------------------------------------------------*/
1698 /* createRegMask - for each instruction will determine the regsUsed */
1699 /*-----------------------------------------------------------------*/
1701 createRegMask (eBBlock ** ebbs, int count)
1705 /* for all blocks */
1706 for (i = 0; i < count; i++)
1710 if (ebbs[i]->noPath &&
1711 (ebbs[i]->entryLabel != entryLabel &&
1712 ebbs[i]->entryLabel != returnLabel))
1715 /* for all instructions */
1716 for (ic = ebbs[i]->sch; ic; ic = ic->next)
1721 if (SKIP_IC2 (ic) || !ic->rlive)
1724 /* first mark the registers used in this
1726 ic->rUsed = regsUsedIniCode (ic);
1727 _G.funcrUsed = bitVectUnion (_G.funcrUsed, ic->rUsed);
1729 /* now create the register mask for those
1730 registers that are in use : this is a
1731 super set of ic->rUsed */
1732 ic->rMask = newBitVect (ds390_nRegs + 1);
1734 /* for all live Ranges alive at this point */
1735 for (j = 1; j < ic->rlive->size; j++)
1740 /* if not alive then continue */
1741 if (!bitVectBitValue (ic->rlive, j))
1744 /* find the live range we are interested in */
1745 if (!(sym = hTabItemWithKey (liveRanges, j)))
1747 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
1748 "createRegMask cannot find live range");
1752 /* special case for ruonly */
1753 if (sym->ruonly && sym->liveFrom != sym->liveTo) {
1754 int size = getSize(sym->type);
1756 for (k = 0 ; k < size; k++ )
1757 ic->rMask = bitVectSetBit (ic->rMask, j++);
1761 /* if no register assigned to it */
1762 if (!sym->nRegs || sym->isspilt)
1765 /* for all the registers allocated to it */
1766 for (k = 0; k < sym->nRegs; k++)
1769 bitVectSetBit (ic->rMask, sym->regs[k]->rIdx);
1775 /*-----------------------------------------------------------------*/
1776 /* rematStr - returns the rematerialized string for a remat var */
1777 /*-----------------------------------------------------------------*/
1779 rematStr (symbol * sym)
1782 iCode *ic = sym->rematiCode;
1789 /* if plus or minus print the right hand side */
1790 if (ic->op == '+' || ic->op == '-')
1792 SNPRINTF (s, sizeof(buffer) - strlen(buffer),
1793 "0x%04x %c ", (int) operandLitValue (IC_RIGHT (ic)),
1796 ic = OP_SYMBOL (IC_LEFT (ic))->rematiCode;
1799 /* cast then continue */
1800 if (IS_CAST_ICODE(ic)) {
1801 ic = OP_SYMBOL (IC_RIGHT (ic))->rematiCode;
1804 /* we reached the end */
1805 SNPRINTF (s, sizeof(buffer) - strlen(buffer),
1806 "%s", OP_SYMBOL (IC_LEFT (ic))->rname);
1813 /*-----------------------------------------------------------------*/
1814 /* regTypeNum - computes the type & number of registers required */
1815 /*-----------------------------------------------------------------*/
1823 /* for each live range do */
1824 for (sym = hTabFirstItem (liveRanges, &k); sym;
1825 sym = hTabNextItem (liveRanges, &k))
1828 /* if used zero times then no registers needed */
1829 if ((sym->liveTo - sym->liveFrom) == 0)
1833 /* if the live range is a temporary */
1837 /* if the type is marked as a conditional */
1838 if (sym->regType == REG_CND)
1841 /* if used in return only then we don't
1843 if (sym->ruonly || sym->accuse)
1845 if (IS_AGGREGATE (sym->type) || sym->isptr)
1846 sym->type = aggrToPtr (sym->type, FALSE);
1850 /* if the symbol has only one definition &
1851 that definition is a get_pointer */
1852 if (bitVectnBitsOn (sym->defs) == 1 &&
1853 (ic = hTabItemWithKey (iCodehTab,
1854 bitVectFirstBit (sym->defs))) &&
1857 !IS_BITVAR (sym->etype))
1859 /* and that pointer is remat in data space */
1860 if (IS_SYMOP (IC_LEFT (ic)) &&
1861 OP_SYMBOL (IC_LEFT (ic))->remat &&
1862 !IS_CAST_ICODE(OP_SYMBOL (IC_LEFT (ic))->rematiCode) &&
1863 DCL_TYPE (aggrToPtr (operandType(IC_LEFT(ic)), FALSE)) == POINTER)
1866 /* create a psuedo symbol & force a spil */
1867 symbol *psym = newSymbol (rematStr (OP_SYMBOL (IC_LEFT (ic))), 1);
1868 psym->type = sym->type;
1869 psym->etype = sym->etype;
1870 strncpyz (psym->rname, psym->name, sizeof(psym->rname));
1872 sym->usl.spillLoc = psym;
1876 /* if in data space or idata space then try to
1877 allocate pointer register */
1881 /* if not then we require registers */
1882 sym->nRegs = ((IS_AGGREGATE (sym->type) || sym->isptr) ?
1883 getSize (sym->type = aggrToPtr (sym->type, FALSE)) :
1884 getSize (sym->type));
1888 fprintf (stderr, "allocated more than 4 or 0 registers for type ");
1889 printTypeChain (sym->type, stderr);
1890 fprintf (stderr, "\n");
1893 /* determine the type of register required */
1894 if (sym->nRegs == 1 &&
1895 IS_PTR (sym->type) &&
1897 sym->regType = REG_PTR;
1899 sym->regType = REG_GPR;
1903 /* for the first run we don't provide */
1904 /* registers for true symbols we will */
1905 /* see how things go */
1911 /*-----------------------------------------------------------------*/
1912 /* freeAllRegs - mark all registers as free */
1913 /*-----------------------------------------------------------------*/
1919 for (i = 0; i < ds390_nRegs; i++)
1920 regs390[i].isFree = 1;
1923 /*-----------------------------------------------------------------*/
1924 /* deallocStackSpil - this will set the stack pointer back */
1925 /*-----------------------------------------------------------------*/
1927 DEFSETFUNC (deallocStackSpil)
1935 /*-----------------------------------------------------------------*/
1936 /* farSpacePackable - returns the packable icode for far variables */
1937 /*-----------------------------------------------------------------*/
1939 farSpacePackable (iCode * ic)
1943 /* go thru till we find a definition for the
1944 symbol on the right */
1945 for (dic = ic->prev; dic; dic = dic->prev)
1948 /* if the definition is a call then no */
1949 if ((dic->op == CALL || dic->op == PCALL) &&
1950 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1955 /* if shift by unknown amount then not */
1956 if ((dic->op == LEFT_OP || dic->op == RIGHT_OP) &&
1957 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1960 /* if pointer get and size > 1 */
1961 if (POINTER_GET (dic) &&
1962 getSize (aggrToPtr (operandType (IC_LEFT (dic)), FALSE)) > 1)
1965 if (POINTER_SET (dic) &&
1966 getSize (aggrToPtr (operandType (IC_RESULT (dic)), FALSE)) > 1)
1969 /* if any three is a true symbol in far space */
1970 if (IC_RESULT (dic) &&
1971 IS_TRUE_SYMOP (IC_RESULT (dic)) &&
1972 isOperandInFarSpace (IC_RESULT (dic)))
1975 if (IC_RIGHT (dic) &&
1976 IS_TRUE_SYMOP (IC_RIGHT (dic)) &&
1977 isOperandInFarSpace (IC_RIGHT (dic)) &&
1978 !isOperandEqual (IC_RIGHT (dic), IC_RESULT (ic)))
1981 if (IC_LEFT (dic) &&
1982 IS_TRUE_SYMOP (IC_LEFT (dic)) &&
1983 isOperandInFarSpace (IC_LEFT (dic)) &&
1984 !isOperandEqual (IC_LEFT (dic), IC_RESULT (ic)))
1987 if (isOperandEqual (IC_RIGHT (ic), IC_RESULT (dic)))
1989 if ((dic->op == LEFT_OP ||
1990 dic->op == RIGHT_OP ||
1992 IS_OP_LITERAL (IC_RIGHT (dic)))
2002 /*-----------------------------------------------------------------*/
2003 /* packRegsForAssign - register reduction for assignment */
2004 /*-----------------------------------------------------------------*/
2006 packRegsForAssign (iCode * ic, eBBlock * ebp)
2010 if (!IS_ITEMP (IC_RIGHT (ic)) ||
2011 OP_SYMBOL (IC_RIGHT (ic))->isind ||
2012 OP_LIVETO (IC_RIGHT (ic)) > ic->seq)
2017 /* if the true symbol is defined in far space or on stack
2018 then we should not since this will increase register pressure */
2020 if (isOperandInFarSpace (IC_RESULT (ic)))
2022 if ((dic = farSpacePackable (ic)))
2028 if (isOperandInFarSpace(IC_RESULT(ic)) && !farSpacePackable(ic)) {
2033 /* find the definition of iTempNN scanning backwards if we find a
2034 a use of the true symbol in before we find the definition then
2036 for (dic = ic->prev; dic; dic = dic->prev)
2038 /* if there is a function call then don't pack it */
2039 if ((dic->op == CALL || dic->op == PCALL))
2048 if (IS_TRUE_SYMOP (IC_RESULT (dic)) &&
2049 IS_OP_VOLATILE (IC_RESULT (dic)))
2055 if (IS_SYMOP (IC_RESULT (dic)) &&
2056 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
2058 if (POINTER_SET (dic))
2064 if (IS_SYMOP (IC_RIGHT (dic)) &&
2065 (IC_RIGHT (dic)->key == IC_RESULT (ic)->key ||
2066 IC_RIGHT (dic)->key == IC_RIGHT (ic)->key))
2072 if (IS_SYMOP (IC_LEFT (dic)) &&
2073 (IC_LEFT (dic)->key == IC_RESULT (ic)->key ||
2074 IC_LEFT (dic)->key == IC_RIGHT (ic)->key))
2080 if (POINTER_SET (dic) &&
2081 IC_RESULT (dic)->key == IC_RESULT (ic)->key)
2089 return 0; /* did not find */
2091 /* if the result is on stack or iaccess then it must be
2092 the same atleast one of the operands */
2093 if (OP_SYMBOL (IC_RESULT (ic))->onStack ||
2094 OP_SYMBOL (IC_RESULT (ic))->iaccess)
2097 /* the operation has only one symbol
2098 operator then we can pack */
2099 if ((IC_LEFT (dic) && !IS_SYMOP (IC_LEFT (dic))) ||
2100 (IC_RIGHT (dic) && !IS_SYMOP (IC_RIGHT (dic))))
2103 if (!((IC_LEFT (dic) &&
2104 IC_RESULT (ic)->key == IC_LEFT (dic)->key) ||
2106 IC_RESULT (ic)->key == IC_RIGHT (dic)->key)))
2110 /* found the definition */
2111 /* replace the result with the result of */
2112 /* this assignment and remove this assignment */
2113 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2115 IC_RESULT (dic) = IC_RESULT (ic);
2117 if (IS_ITEMP (IC_RESULT (dic)) && OP_SYMBOL (IC_RESULT (dic))->liveFrom > dic->seq)
2119 OP_SYMBOL (IC_RESULT (dic))->liveFrom = dic->seq;
2121 /* delete from liverange table also
2122 delete from all the points inbetween and the new
2124 for (sic = dic; sic != ic; sic = sic->next)
2126 bitVectUnSetBit (sic->rlive, IC_RESULT (ic)->key);
2127 if (IS_ITEMP (IC_RESULT (dic)))
2128 bitVectSetBit (sic->rlive, IC_RESULT (dic)->key);
2131 remiCodeFromeBBlock (ebp, ic);
2132 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
2133 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
2134 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
2139 /*-----------------------------------------------------------------*/
2140 /* findAssignToSym : scanning backwards looks for first assig found */
2141 /*-----------------------------------------------------------------*/
2143 findAssignToSym (operand * op, iCode * ic)
2147 for (dic = ic->prev; dic; dic = dic->prev)
2150 /* if definition by assignment */
2151 if (dic->op == '=' &&
2152 !POINTER_SET (dic) &&
2153 IC_RESULT (dic)->key == op->key
2154 /* && IS_TRUE_SYMOP(IC_RIGHT(dic)) */
2158 /* we are interested only if defined in far space */
2159 /* or in stack space in case of + & - */
2161 /* if assigned to a non-symbol then return
2163 if (!IS_SYMOP (IC_RIGHT (dic)))
2166 /* if the symbol is in far space then
2168 if (isOperandInFarSpace (IC_RIGHT (dic)))
2171 /* for + & - operations make sure that
2172 if it is on the stack it is the same
2173 as one of the three operands */
2174 if ((ic->op == '+' || ic->op == '-') &&
2175 OP_SYMBOL (IC_RIGHT (dic))->onStack)
2178 if (IC_RESULT (ic)->key != IC_RIGHT (dic)->key &&
2179 IC_LEFT (ic)->key != IC_RIGHT (dic)->key &&
2180 IC_RIGHT (ic)->key != IC_RIGHT (dic)->key)
2188 /* if we find an usage then we cannot delete it */
2189 if (IC_LEFT (dic) && IC_LEFT (dic)->key == op->key)
2192 if (IC_RIGHT (dic) && IC_RIGHT (dic)->key == op->key)
2195 if (POINTER_SET (dic) && IC_RESULT (dic)->key == op->key)
2199 /* now make sure that the right side of dic
2200 is not defined between ic & dic */
2203 iCode *sic = dic->next;
2205 for (; sic != ic; sic = sic->next)
2206 if (IC_RESULT (sic) &&
2207 IC_RESULT (sic)->key == IC_RIGHT (dic)->key)
2216 /*-----------------------------------------------------------------*/
2217 /* packRegsForSupport :- reduce some registers for support calls */
2218 /*-----------------------------------------------------------------*/
2220 packRegsForSupport (iCode * ic, eBBlock * ebp)
2224 /* for the left & right operand :- look to see if the
2225 left was assigned a true symbol in far space in that
2226 case replace them */
2227 if (IS_ITEMP (IC_LEFT (ic)) &&
2228 OP_SYMBOL (IC_LEFT (ic))->liveTo <= ic->seq)
2230 iCode *dic = findAssignToSym (IC_LEFT (ic), ic);
2236 /* found it we need to remove it from the
2238 for (sic = dic; sic != ic; sic = sic->next) {
2239 bitVectUnSetBit (sic->rlive, IC_LEFT (ic)->key);
2240 sic->rlive = bitVectSetBit (sic->rlive, IC_RIGHT (dic)->key);
2243 wassert(IS_SYMOP(IC_LEFT (ic)));
2244 wassert(IS_SYMOP(IC_RIGHT (dic)));
2245 IC_LEFT (ic)->operand.symOperand =
2246 IC_RIGHT (dic)->operand.symOperand;
2247 OP_SYMBOL(IC_LEFT(ic))->liveTo = ic->seq;
2248 IC_LEFT (ic)->key = IC_RIGHT (dic)->operand.symOperand->key;
2249 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2250 remiCodeFromeBBlock (ebp, dic);
2251 hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
2255 /* do the same for the right operand */
2258 IS_ITEMP (IC_RIGHT (ic)) &&
2259 OP_SYMBOL (IC_RIGHT (ic))->liveTo <= ic->seq)
2261 iCode *dic = findAssignToSym (IC_RIGHT (ic), ic);
2267 /* if this is a subtraction & the result
2268 is a true symbol in far space then don't pack */
2269 if (ic->op == '-' && IS_TRUE_SYMOP (IC_RESULT (dic)))
2271 sym_link *etype = getSpec (operandType (IC_RESULT (dic)));
2272 if (IN_FARSPACE (SPEC_OCLS (etype)))
2275 /* found it we need to remove it from the
2277 for (sic = dic; sic != ic; sic = sic->next) {
2278 bitVectUnSetBit (sic->rlive, IC_RIGHT (ic)->key);
2279 sic->rlive = bitVectSetBit (sic->rlive, IC_RIGHT (dic)->key);
2282 wassert(IS_SYMOP(IC_RIGHT (ic)));
2283 wassert(IS_SYMOP(IC_RIGHT (dic)));
2284 IC_RIGHT (ic)->operand.symOperand =
2285 IC_RIGHT (dic)->operand.symOperand;
2286 IC_RIGHT (ic)->key = IC_RIGHT (dic)->operand.symOperand->key;
2287 OP_SYMBOL(IC_RIGHT(ic))->liveTo = ic->seq;
2288 remiCodeFromeBBlock (ebp, dic);
2289 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2290 hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
2297 #define IS_OP_RUONLY(x) (x && IS_SYMOP(x) && OP_SYMBOL(x)->ruonly)
2300 /*-----------------------------------------------------------------*/
2301 /* packRegsDPTRnuse - color live ranges that can go into extra DPTRS */
2302 /*-----------------------------------------------------------------*/
2303 static int packRegsDPTRnuse( operand *op , int dptr)
2308 if (!IS_SYMOP(op) || !IS_ITEMP(op)) return 0;
2309 if (OP_SYMBOL(op)->remat || OP_SYMBOL(op)->ruonly || OP_SYMBOL(op)->dptr)
2312 /* first check if any overlapping liverange has already been
2313 assigned to this DPTR */
2314 if (OP_SYMBOL(op)->clashes) {
2315 for (i = 0 ; i < OP_SYMBOL(op)->clashes->size ; i++ ) {
2317 if (bitVectBitValue(OP_SYMBOL(op)->clashes,i)) {
2318 sym = hTabItemWithKey(liveRanges,i);
2319 if (sym->dptr == dptr) return 0;
2324 /* future for more dptrs */
2326 OP_SYMBOL(op)->dptr = dptr;
2330 /* DPTR1 is special since it is also used as a scratch by the backend .
2331 so we walk thru the entire live range of this operand and make sure
2332 DPTR1 will not be used by the backed . The logic here is to find out if
2333 more than one operand in an icode is in far space then we give up : we
2334 don't keep it live across functions for now
2337 ic = hTabFirstItemWK(iCodeSeqhTab,OP_SYMBOL(op)->liveFrom);
2338 for (; ic && ic->seq <= OP_SYMBOL(op)->liveTo;
2339 ic = hTabNextItem(iCodeSeqhTab,&key)) {
2342 if (ic->op == CALL || ic->op == PCALL) return 0;
2344 /* single operand icode are ok */
2345 if (ic->op == IFX || ic->op == IPUSH)
2348 if (ic->op == SEND ) {
2349 if (ic->argreg != 1 ) return 0;
2352 /* two special cases first */
2353 if (POINTER_GET(ic) && !isOperandEqual(IC_LEFT(ic),op) && /* pointer get */
2354 !OP_SYMBOL(IC_LEFT(ic))->ruonly && /* with result in far space */
2355 (isOperandInFarSpace(IC_RESULT(ic)) &&
2356 !isOperandInReg(IC_RESULT(ic)))) {
2360 if (POINTER_SET(ic) && !isOperandEqual(IC_RESULT(ic),op) && /* pointer set */
2361 !OP_SYMBOL(IC_RESULT(ic))->ruonly && /* with right in far space */
2362 (isOperandInFarSpace(IC_RIGHT(ic)) &&
2363 !isOperandInReg(IC_RIGHT(ic)))) {
2367 if (IC_RESULT(ic) && IS_SYMOP(IC_RESULT(ic)) && /* if symbol operand */
2368 !isOperandEqual(IC_RESULT(ic),op) && /* not the same as this */
2369 ((isOperandInFarSpace(IC_RESULT(ic)) || /* in farspace or */
2370 OP_SYMBOL(IC_RESULT(ic))->onStack) && /* on the stack */
2371 !isOperandInReg(IC_RESULT(ic)))) { /* and not in register */
2375 if (IC_LEFT(ic) && IS_SYMOP(IC_LEFT(ic)) && /* if symbol operand */
2376 !isOperandEqual(IC_LEFT(ic),op) && /* not the same as this */
2377 ((isOperandInFarSpace(IC_LEFT(ic)) || /* in farspace or */
2378 OP_SYMBOL(IC_LEFT(ic))->onStack) && /* on the stack */
2379 !isOperandInReg(IC_LEFT(ic)))) { /* and not in register */
2382 /* same for right */
2383 if (IC_RIGHT(ic) && IS_SYMOP(IC_RIGHT(ic)) && /* if symbol operand */
2384 !isOperandEqual(IC_RIGHT(ic),op) && /* not the same as this */
2385 ((isOperandInFarSpace(IC_RIGHT(ic)) || /* in farspace or */
2386 OP_SYMBOL(IC_RIGHT(ic))->onStack) && /* on the stack */
2387 !isOperandInReg(IC_RIGHT(ic)))) { /* and not in register */
2391 // Check that no other ops in this range have been assigned to dptr1.
2392 // I don't understand why this is not caught by the first check, above.
2393 // But it isn't always, see bug 769624.
2394 if (IC_RESULT(ic) && IS_SYMOP(IC_RESULT(ic)) &&
2395 (OP_SYMBOL(IC_RESULT(ic))->dptr == 1))
2397 //fprintf(stderr, "dptr1 already in use in live range #1\n");
2401 if (IC_LEFT(ic) && IS_SYMOP(IC_LEFT(ic)) &&
2402 (OP_SYMBOL(IC_LEFT(ic))->dptr == 1))
2404 //fprintf(stderr, "dptr1 already in use in live range # 2\n");
2408 if (IC_RIGHT(ic) && IS_SYMOP(IC_RIGHT(ic)) &&
2409 (OP_SYMBOL(IC_RIGHT(ic))->dptr == 1))
2411 //fprintf(stderr, "dptr1 already in use in live range # 3\n");
2415 if (nfs && IC_RESULT(ic) && IS_SYMOP(IC_RESULT(ic)) &&
2416 OP_SYMBOL(IC_RESULT(ic))->ruonly) return 0;
2418 if (nfs > 1) return 0;
2420 OP_SYMBOL(op)->dptr = dptr;
2424 /*-----------------------------------------------------------------*/
2425 /* packRegsDPTRuse : - will reduce some registers for single Use */
2426 /*-----------------------------------------------------------------*/
2428 packRegsDPTRuse (operand * op)
2430 /* go thru entire liveRange of this variable & check for
2431 other possible usage of DPTR , if we don't find it the
2432 assign this to DPTR (ruonly)
2437 sym_link *type, *etype;
2439 if (!IS_SYMOP(op) || !IS_ITEMP(op)) return NULL;
2440 if (OP_SYMBOL(op)->remat || OP_SYMBOL(op)->ruonly) return NULL;
2442 /* first check if any overlapping liverange has already been
2444 if (OP_SYMBOL(op)->clashes) {
2445 for (i = 0 ; i < OP_SYMBOL(op)->clashes->size ; i++ ) {
2446 if (bitVectBitValue(OP_SYMBOL(op)->clashes,i)) {
2447 sym = hTabItemWithKey(liveRanges,i);
2448 if (sym->ruonly) return NULL ;
2453 /* no then go thru this guys live range */
2454 dic = ic = hTabFirstItemWK(iCodeSeqhTab,OP_SYMBOL(op)->liveFrom);
2455 for (; ic && ic->seq <= OP_SYMBOL(op)->liveTo;
2456 ic = hTabNextItem(iCodeSeqhTab,&key)) {
2458 if (SKIP_IC3(ic)) continue;
2460 /* if PCALL cannot be sure give up */
2461 if (ic->op == PCALL) return NULL;
2463 /* if SEND & not the first parameter then giveup */
2464 if (ic->op == SEND && ic->argreg != 1 &&
2465 ((isOperandInFarSpace(IC_LEFT(ic)) && !isOperandInReg(IC_LEFT(ic))) ||
2466 isOperandEqual(op,IC_LEFT(ic)))) return NULL;
2468 /* if CALL then make sure it is VOID || return value not used
2469 or the return value is assigned to this one */
2470 if (ic->op == CALL) {
2471 if (OP_SYMBOL(IC_RESULT(ic))->liveTo ==
2472 OP_SYMBOL(IC_RESULT(ic))->liveFrom) continue ;
2473 etype = getSpec(type = operandType(IC_RESULT(ic)));
2474 if (getSize(type) == 0 || isOperandEqual(op,IC_RESULT(ic)))
2479 /* special case of add with a [remat] */
2480 if (ic->op == '+' &&
2481 OP_SYMBOL(IC_LEFT(ic))->remat &&
2482 (isOperandInFarSpace(IC_RIGHT(ic)) &&
2483 !isOperandInReg(IC_RIGHT(ic)))) return NULL ;
2487 if (POINTER_GET(ic) && !isOperandEqual(IC_LEFT(ic),op) &&
2488 getSize(operandType(IC_LEFT(ic))) > 1 ) return NULL ;
2491 if (POINTER_SET(ic) && !isOperandEqual(IC_RESULT(ic),op) &&
2492 getSize(operandType(IC_RESULT(ic))) > 1 ) return NULL;
2494 /* conditionals can destroy 'b' - make sure B wont
2495 be used in this one*/
2496 if ((IS_CONDITIONAL(ic) || ic->op == '*' || ic->op == '/' ||
2497 ic->op == LEFT_OP || ic->op == RIGHT_OP ) &&
2498 getSize(operandType(op)) > 3) return NULL;
2500 /* if this is a cast to a bigger type */
2502 if (!IS_PTR(OP_SYM_TYPE(IC_RESULT(ic))) &&
2503 getSize(OP_SYM_TYPE(IC_RESULT(ic))) >
2504 getSize(OP_SYM_TYPE(IC_RIGHT(ic)))) {
2510 if (IC_RESULT(ic) && IS_SYMOP(IC_RESULT(ic)) &&
2511 !isOperandEqual(IC_RESULT(ic),op) &&
2512 ( ( ( isOperandInFarSpace(IC_RESULT(ic)) || OP_SYMBOL(IC_RESULT(ic))->onStack) &&
2513 !isOperandInReg(IC_RESULT(ic))) ||
2514 OP_SYMBOL(IC_RESULT(ic))->ruonly)) return NULL;
2516 if (IC_RIGHT(ic) && IS_SYMOP(IC_RIGHT(ic)) &&
2517 !isOperandEqual(IC_RIGHT(ic),op) &&
2518 (OP_SYMBOL(IC_RIGHT(ic))->liveTo >= ic->seq ||
2519 IS_TRUE_SYMOP(IC_RIGHT(ic)) ||
2520 OP_SYMBOL(IC_RIGHT(ic))->ruonly) &&
2521 ( ( isOperandInFarSpace(IC_RIGHT(ic)) || OP_SYMBOL(IC_RIGHT(ic))->onStack) &&
2522 !isOperandInReg(IC_RIGHT(ic))) ) return NULL;
2524 if (IC_LEFT(ic) && IS_SYMOP(IC_LEFT(ic)) &&
2525 !isOperandEqual(IC_LEFT(ic),op) &&
2526 (OP_SYMBOL(IC_LEFT(ic))->liveTo >= ic->seq ||
2527 IS_TRUE_SYMOP(IC_LEFT(ic)) ||
2528 OP_SYMBOL(IC_LEFT(ic))->ruonly) &&
2529 ( ( isOperandInFarSpace(IC_LEFT(ic)) || OP_SYMBOL(IC_LEFT(ic))->onStack) &&
2530 !isOperandInReg(IC_LEFT(ic))) ) return NULL;
2532 if (IC_LEFT(ic) && IC_RIGHT(ic) &&
2533 IS_ITEMP(IC_LEFT(ic)) && IS_ITEMP(IC_RIGHT(ic)) &&
2534 (isOperandInFarSpace(IC_LEFT(ic)) && !isOperandInReg(IC_LEFT(ic))) &&
2535 (isOperandInFarSpace(IC_RIGHT(ic)) && !isOperandInReg(IC_RIGHT(ic))))
2538 OP_SYMBOL(op)->ruonly = 1;
2539 if (OP_SYMBOL(op)->usl.spillLoc) {
2540 if (OP_SYMBOL(op)->spillA)
2541 OP_SYMBOL(op)->usl.spillLoc->allocreq--;
2542 OP_SYMBOL(op)->usl.spillLoc = NULL;
2547 /*-----------------------------------------------------------------*/
2548 /* isBitwiseOptimizable - requirements of JEAN LOUIS VERN */
2549 /*-----------------------------------------------------------------*/
2551 isBitwiseOptimizable (iCode * ic)
2553 sym_link *ltype = getSpec (operandType (IC_LEFT (ic)));
2554 sym_link *rtype = getSpec (operandType (IC_RIGHT (ic)));
2556 /* bitwise operations are considered optimizable
2557 under the following conditions (Jean-Louis VERN)
2569 if ( IS_LITERAL (rtype) ||
2570 (IS_BITVAR (ltype) && IN_BITSPACE (SPEC_OCLS (ltype))))
2576 /*-----------------------------------------------------------------*/
2577 /* packRegsForAccUse - pack registers for acc use */
2578 /*-----------------------------------------------------------------*/
2580 packRegsForAccUse (iCode * ic)
2584 /* if this is an aggregate, e.g. a one byte char array */
2585 if (IS_AGGREGATE(operandType(IC_RESULT(ic)))) {
2589 /* if we are calling a reentrant function that has stack parameters */
2590 if (ic->op == CALL &&
2591 IFFUNC_ISREENT(operandType(IC_LEFT(ic))) &&
2592 FUNC_HASSTACKPARM(operandType(IC_LEFT(ic))))
2595 if (ic->op == PCALL &&
2596 IFFUNC_ISREENT(operandType(IC_LEFT(ic))->next) &&
2597 FUNC_HASSTACKPARM(operandType(IC_LEFT(ic))->next))
2600 /* if + or - then it has to be one byte result */
2601 if ((ic->op == '+' || ic->op == '-')
2602 && getSize (operandType (IC_RESULT (ic))) > 1)
2605 /* if shift operation make sure right side is not a literal */
2606 if (ic->op == RIGHT_OP &&
2607 (isOperandLiteral (IC_RIGHT (ic)) ||
2608 getSize (operandType (IC_RESULT (ic))) > 1))
2611 if (ic->op == LEFT_OP &&
2612 (isOperandLiteral (IC_RIGHT (ic)) ||
2613 getSize (operandType (IC_RESULT (ic))) > 1))
2616 if (IS_BITWISE_OP (ic) &&
2617 getSize (operandType (IC_RESULT (ic))) > 1)
2621 /* has only one definition */
2622 if (bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) > 1)
2625 /* has only one use */
2626 if (bitVectnBitsOn (OP_USES (IC_RESULT (ic))) > 1)
2629 /* and the usage immediately follows this iCode */
2630 if (!(uic = hTabItemWithKey (iCodehTab,
2631 bitVectFirstBit (OP_USES (IC_RESULT (ic))))))
2634 if (ic->next != uic)
2637 /* if it is a conditional branch then we definitely can */
2641 if (uic->op == JUMPTABLE)
2644 /* if the usage is not is an assignment
2645 or an arithmetic / bitwise / shift operation then not */
2646 if (POINTER_SET (uic) &&
2647 getSize (aggrToPtr (operandType (IC_RESULT (uic)), FALSE)) > 1)
2650 if (uic->op != '=' &&
2651 !IS_ARITHMETIC_OP (uic) &&
2652 !IS_BITWISE_OP (uic) &&
2653 uic->op != LEFT_OP &&
2654 uic->op != RIGHT_OP)
2657 /* if used in ^ operation then make sure right is not a
2659 if (uic->op == '^' && isOperandLiteral (IC_RIGHT (uic)))
2662 /* if shift operation make sure right side is not a literal */
2663 if (uic->op == RIGHT_OP &&
2664 (isOperandLiteral (IC_RIGHT (uic)) ||
2665 getSize (operandType (IC_RESULT (uic))) > 1))
2668 if (uic->op == LEFT_OP &&
2669 (isOperandLiteral (IC_RIGHT (uic)) ||
2670 getSize (operandType (IC_RESULT (uic))) > 1))
2673 /* make sure that the result of this icode is not on the
2674 stack, since acc is used to compute stack offset */
2675 if (isOperandOnStack(IC_RESULT(uic)))
2678 /* if either one of them in far space then we cannot */
2679 if ((IS_TRUE_SYMOP (IC_LEFT (uic)) &&
2680 isOperandInFarSpace (IC_LEFT (uic))) ||
2681 (IS_TRUE_SYMOP (IC_RIGHT (uic)) &&
2682 isOperandInFarSpace (IC_RIGHT (uic))))
2685 /* if the usage has only one operand then we can */
2686 if (IC_LEFT (uic) == NULL ||
2687 IC_RIGHT (uic) == NULL)
2690 /* make sure this is on the left side if not
2691 a '+' since '+' is commutative */
2692 if (ic->op != '+' &&
2693 IC_LEFT (uic)->key != IC_RESULT (ic)->key)
2696 /* if the other one is not on stack then we can */
2697 if (IC_LEFT (uic)->key == IC_RESULT (ic)->key &&
2698 (IS_ITEMP (IC_RIGHT (uic)) ||
2699 (IS_TRUE_SYMOP (IC_RIGHT (uic)) &&
2700 !OP_SYMBOL (IC_RIGHT (uic))->onStack)))
2703 if (IC_RIGHT (uic)->key == IC_RESULT (ic)->key &&
2704 (IS_ITEMP (IC_LEFT (uic)) ||
2705 (IS_TRUE_SYMOP (IC_LEFT (uic)) &&
2706 !OP_SYMBOL (IC_LEFT (uic))->onStack)))
2712 OP_SYMBOL (IC_RESULT (ic))->accuse = 1;
2717 /*-----------------------------------------------------------------*/
2718 /* packForPush - hueristics to reduce iCode for pushing */
2719 /*-----------------------------------------------------------------*/
2721 packForPush (iCode * ic, eBBlock * ebp)
2726 if ((ic->op != IPUSH && ic->op != SEND) || !IS_ITEMP (IC_LEFT (ic)))
2729 /* must have only definition & one usage */
2730 if (bitVectnBitsOn (OP_DEFS (IC_LEFT (ic))) != 1 ||
2731 bitVectnBitsOn (OP_USES (IC_LEFT (ic))) != 1)
2734 /* find the definition */
2735 if (!(dic = hTabItemWithKey (iCodehTab,
2736 bitVectFirstBit (OP_DEFS (IC_LEFT (ic))))))
2739 if (dic->op != '=' || POINTER_SET (dic))
2742 if (dic->eBBlockNum != ic->eBBlockNum) return ;
2744 /* make sure the right side does not have any definitions
2746 dbv = OP_DEFS(IC_RIGHT(dic));
2747 for (lic = ic; lic && lic != dic ; lic = lic->prev) {
2748 if (bitVectBitValue(dbv,lic->key)) return ;
2750 /* make sure they have the same type */
2751 if (IS_SPEC(operandType(IC_LEFT(ic))))
2753 sym_link *itype=operandType(IC_LEFT(ic));
2754 sym_link *ditype=operandType(IC_RIGHT(dic));
2756 if (SPEC_USIGN(itype)!=SPEC_USIGN(ditype) ||
2757 SPEC_LONG(itype)!=SPEC_LONG(ditype))
2760 /* extend the live range of replaced operand if needed */
2761 if (OP_SYMBOL(IC_RIGHT(dic))->liveTo < OP_SYMBOL(IC_LEFT(ic))->liveTo) {
2762 OP_SYMBOL(IC_RIGHT(dic))->liveTo = OP_SYMBOL(IC_LEFT(ic))->liveTo;
2763 OP_SYMBOL(IC_RIGHT(dic))->clashes =
2764 bitVectUnion(OP_SYMBOL(IC_RIGHT(dic))->clashes,
2765 OP_SYMBOL(IC_LEFT(ic))->clashes);
2767 for (lic = ic; lic && lic != dic; lic = lic->prev)
2769 bitVectUnSetBit (lic->rlive, IC_LEFT (ic)->key);
2770 if (IS_ITEMP (IC_RIGHT (dic)))
2771 bitVectSetBit (lic->rlive, IC_RIGHT (dic)->key);
2773 /* we now we know that it has one & only one def & use
2774 and the that the definition is an assignment */
2775 IC_LEFT (ic) = IC_RIGHT (dic);
2777 remiCodeFromeBBlock (ebp, dic);
2778 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2779 hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
2782 /*-----------------------------------------------------------------*/
2783 /* packRegisters - does some transformations to reduce register */
2785 /*-----------------------------------------------------------------*/
2787 packRegisters (eBBlock * ebp)
2797 /* look for assignments of the form */
2798 /* iTempNN = TRueSym (someoperation) SomeOperand */
2800 /* TrueSym := iTempNN:1 */
2801 for (ic = ebp->sch; ic; ic = ic->next)
2805 /* find assignment of the form TrueSym := iTempNN:1 */
2806 if (ic->op == '=' && !POINTER_SET (ic))
2807 change += packRegsForAssign (ic, ebp);
2814 for (ic = ebp->sch; ic; ic = ic->next)
2817 /* if this is an itemp & result of a address of a true sym
2818 then mark this as rematerialisable */
2819 if (ic->op == ADDRESS_OF &&
2820 IS_ITEMP (IC_RESULT (ic)) &&
2821 IS_TRUE_SYMOP (IC_LEFT (ic)) &&
2822 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1 &&
2823 !OP_SYMBOL (IC_LEFT (ic))->onStack)
2826 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2827 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2828 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2832 /* if this is an itemp & used as a pointer
2833 & assigned to a literal then remat */
2834 if (IS_ASSIGN_ICODE(ic) &&
2835 IS_ITEMP(IC_RESULT(ic)) &&
2836 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1 &&
2837 isOperandLiteral(IC_RIGHT(ic)))
2839 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2840 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2841 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2844 /* if straight assignment then carry remat flag if
2845 this is the only definition */
2846 if (ic->op == '=' &&
2847 !POINTER_SET (ic) &&
2848 IS_SYMOP (IC_RIGHT (ic)) &&
2849 OP_SYMBOL (IC_RIGHT (ic))->remat &&
2850 !IS_CAST_ICODE(OP_SYMBOL (IC_RIGHT (ic))->rematiCode) &&
2851 bitVectnBitsOn (OP_SYMBOL (IC_RESULT (ic))->defs) <= 1)
2854 OP_SYMBOL (IC_RESULT (ic))->remat =
2855 OP_SYMBOL (IC_RIGHT (ic))->remat;
2856 OP_SYMBOL (IC_RESULT (ic))->rematiCode =
2857 OP_SYMBOL (IC_RIGHT (ic))->rematiCode;
2860 /* if cast to a generic pointer & the pointer being
2861 cast is remat, then we can remat this cast as well */
2862 if (ic->op == CAST &&
2863 IS_SYMOP(IC_RIGHT(ic)) &&
2864 !OP_SYMBOL(IC_RESULT(ic))->isreqv &&
2865 OP_SYMBOL(IC_RIGHT(ic))->remat ) {
2866 sym_link *to_type = operandType(IC_LEFT(ic));
2867 sym_link *from_type = operandType(IC_RIGHT(ic));
2868 if (IS_GENPTR(to_type) && IS_PTR(from_type)) {
2869 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2870 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2871 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2875 /* if this is a +/- operation with a rematerizable
2876 then mark this as rematerializable as well */
2877 if ((ic->op == '+' || ic->op == '-') &&
2878 (IS_SYMOP (IC_LEFT (ic)) &&
2879 IS_ITEMP (IC_RESULT (ic)) &&
2880 OP_SYMBOL (IC_LEFT (ic))->remat &&
2881 (!IS_SYMOP (IC_RIGHT (ic)) || !IS_CAST_ICODE(OP_SYMBOL (IC_RIGHT (ic))->rematiCode)) &&
2882 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1 &&
2883 IS_OP_LITERAL (IC_RIGHT (ic))))
2886 //int i = operandLitValue(IC_RIGHT(ic));
2887 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2888 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2889 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2892 /* mark the pointer usages */
2893 if (POINTER_SET (ic) && IS_SYMOP (IC_RESULT (ic)))
2894 OP_SYMBOL (IC_RESULT (ic))->uptr = 1;
2896 if (POINTER_GET (ic) && IS_SYMOP (IC_LEFT (ic)))
2897 OP_SYMBOL (IC_LEFT (ic))->uptr = 1;
2899 if (ic->op == RETURN && IS_SYMOP (IC_LEFT(ic)))
2900 OP_SYMBOL (IC_LEFT (ic))->uptr = 1;
2902 if (ic->op == RECEIVE && ic->argreg == 1 &&
2903 IS_SYMOP (IC_RESULT (ic)) &&
2904 getSize (operandType(IC_RESULT(ic))) <= 3)
2905 OP_SYMBOL (IC_RESULT(ic))->uptr = 1;
2907 if (ic->op == SEND && ic->argreg == 1 &&
2908 IS_SYMOP(IC_LEFT(ic)) &&
2909 getSize (aggrToPtr(operandType(IC_LEFT(ic)),FALSE)) <= 3)
2910 OP_SYMBOL (IC_LEFT(ic))->uptr = 1;
2914 /* if we are using a symbol on the stack
2915 then we should say ds390_ptrRegReq */
2916 if (options.useXstack && ic->parmPush
2917 && (ic->op == IPUSH || ic->op == IPOP))
2919 if (ic->op == IFX && IS_SYMOP (IC_COND (ic)))
2920 ds390_ptrRegReq += ((OP_SYMBOL (IC_COND (ic))->onStack ? !options.stack10bit : 0) +
2921 OP_SYMBOL (IC_COND (ic))->iaccess +
2922 (SPEC_OCLS(OP_SYMBOL (IC_COND (ic))->etype) == idata));
2923 else if (ic->op == JUMPTABLE && IS_SYMOP (IC_JTCOND (ic)))
2924 ds390_ptrRegReq += ((OP_SYMBOL (IC_JTCOND (ic))->onStack ? !options.stack10bit : 0) +
2925 OP_SYMBOL (IC_JTCOND (ic))->iaccess +
2926 (SPEC_OCLS(OP_SYMBOL (IC_JTCOND (ic))->etype) == idata));
2929 if (IS_SYMOP (IC_LEFT (ic)))
2930 ds390_ptrRegReq += ((OP_SYMBOL (IC_LEFT (ic))->onStack ? !options.stack10bit : 0) +
2931 OP_SYMBOL (IC_LEFT (ic))->iaccess +
2932 (SPEC_OCLS(OP_SYMBOL (IC_LEFT (ic))->etype) == idata));
2933 if (IS_SYMOP (IC_RIGHT (ic)))
2934 ds390_ptrRegReq += ((OP_SYMBOL (IC_RIGHT (ic))->onStack ? !options.stack10bit : 0) +
2935 OP_SYMBOL (IC_RIGHT (ic))->iaccess +
2936 (SPEC_OCLS(OP_SYMBOL (IC_RIGHT (ic))->etype) == idata));
2937 if (IS_SYMOP (IC_RESULT (ic)))
2938 ds390_ptrRegReq += ((OP_SYMBOL (IC_RESULT (ic))->onStack ? !options.stack10bit : 0) +
2939 OP_SYMBOL (IC_RESULT (ic))->iaccess +
2940 (SPEC_OCLS(OP_SYMBOL (IC_RESULT (ic))->etype) == idata));
2944 /* if the condition of an if instruction
2945 is defined in the previous instruction and
2946 this is the only usage then
2947 mark the itemp as a conditional */
2948 if ((IS_CONDITIONAL (ic) ||
2949 (IS_BITWISE_OP(ic) && isBitwiseOptimizable (ic))) &&
2950 ic->next && ic->next->op == IFX &&
2951 bitVectnBitsOn (OP_USES(IC_RESULT(ic)))==1 &&
2952 isOperandEqual (IC_RESULT (ic), IC_COND (ic->next)) &&
2953 OP_SYMBOL (IC_RESULT (ic))->liveTo <= ic->next->seq)
2955 OP_SYMBOL (IC_RESULT (ic))->regType = REG_CND;
2959 /* reduce for support function calls */
2960 if (ic->supportRtn || ic->op == '+' || ic->op == '-')
2961 packRegsForSupport (ic, ebp);
2963 /* some cases the redundant moves can
2964 can be eliminated for return statements . Can be elminated for the first SEND */
2965 if ((ic->op == RETURN ||
2966 ((ic->op == SEND || ic->op == RECEIVE)&& ic->argreg == 1)) &&
2967 !isOperandInFarSpace (IC_LEFT (ic)) &&
2970 packRegsDPTRuse (IC_LEFT (ic));
2973 if (ic->op == CALL) {
2974 sym_link *ftype = operandType(IC_LEFT(ic));
2975 if (getSize(operandType(IC_RESULT(ic))) <= 4 &&
2976 !IFFUNC_ISBUILTIN(ftype)) {
2977 packRegsDPTRuse (IC_RESULT (ic));
2981 /* if pointer set & left has a size more than
2982 one and right is not in far space */
2983 if (POINTER_SET (ic) &&
2984 !isOperandInFarSpace (IC_RIGHT (ic)) &&
2985 IS_SYMOP (IC_RESULT (ic)) &&
2986 !OP_SYMBOL (IC_RESULT (ic))->remat &&
2987 !IS_OP_RUONLY (IC_RIGHT (ic)) &&
2988 getSize (aggrToPtr (operandType (IC_RESULT (ic)), FALSE)) > 1) {
2990 packRegsDPTRuse (IC_RESULT (ic));
2993 /* if pointer get */
2994 if (POINTER_GET (ic) &&
2995 !isOperandInFarSpace (IC_RESULT (ic)) &&
2996 IS_SYMOP (IC_LEFT (ic)) &&
2997 !OP_SYMBOL (IC_LEFT (ic))->remat &&
2998 !IS_OP_RUONLY (IC_RESULT (ic)) &&
2999 getSize (aggrToPtr (operandType (IC_LEFT (ic)), FALSE)) > 1) {
3001 packRegsDPTRuse (IC_LEFT (ic));
3004 /* if this is cast for intergral promotion then
3005 check if only use of the definition of the
3006 operand being casted/ if yes then replace
3007 the result of that arithmetic operation with
3008 this result and get rid of the cast */
3011 sym_link *fromType = operandType (IC_RIGHT (ic));
3012 sym_link *toType = operandType (IC_LEFT (ic));
3014 if (IS_INTEGRAL (fromType) && IS_INTEGRAL (toType) &&
3015 getSize (fromType) != getSize (toType) &&
3016 SPEC_USIGN (fromType) == SPEC_USIGN (toType))
3019 iCode *dic = packRegsDPTRuse (IC_RIGHT (ic));
3022 if (IS_ARITHMETIC_OP (dic))
3024 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
3025 IC_RESULT (dic) = IC_RESULT (ic);
3026 remiCodeFromeBBlock (ebp, ic);
3027 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
3028 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
3029 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
3033 OP_SYMBOL (IC_RIGHT (ic))->ruonly = 0;
3039 /* if the type from and type to are the same
3040 then if this is the only use then packit */
3041 if (compareType (operandType (IC_RIGHT (ic)),
3042 operandType (IC_LEFT (ic))) == 1)
3044 iCode *dic = packRegsDPTRuse (IC_RIGHT (ic));
3047 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
3048 IC_RESULT (dic) = IC_RESULT (ic);
3049 remiCodeFromeBBlock (ebp, ic);
3050 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
3051 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
3052 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
3060 iTempNN := (some variable in farspace) V1
3065 if (ic->op == IPUSH || ic->op == SEND)
3067 packForPush (ic, ebp);
3071 /* pack registers for accumulator use, when the
3072 result of an arithmetic or bit wise operation
3073 has only one use, that use is immediately following
3074 the defintion and the using iCode has only one
3075 operand or has two operands but one is literal &
3076 the result of that operation is not on stack then
3077 we can leave the result of this operation in acc:b
3079 if ((IS_ARITHMETIC_OP (ic)
3080 || IS_CONDITIONAL(ic)
3081 || IS_BITWISE_OP (ic)
3082 || ic->op == LEFT_OP || ic->op == RIGHT_OP
3083 || (ic->op == ADDRESS_OF && isOperandOnStack (IC_LEFT (ic)))
3085 IS_ITEMP (IC_RESULT (ic)) &&
3086 getSize (operandType (IC_RESULT (ic))) <= 2)
3088 packRegsForAccUse (ic);
3093 /*-----------------------------------------------------------------*/
3094 /* assignRegisters - assigns registers to each live range as need */
3095 /*-----------------------------------------------------------------*/
3097 ds390_assignRegisters (eBBlock ** ebbs, int count)
3102 setToNull ((void *) &_G.funcrUsed);
3103 setToNull ((void *) &_G.regAssigned);
3104 setToNull ((void *) &_G.totRegAssigned);
3105 setToNull ((void *) &_G.funcrUsed);
3106 ds390_ptrRegReq = _G.stackExtend = _G.dataExtend = 0;
3108 if (options.model != MODEL_FLAT24) options.stack10bit = 0;
3109 /* change assignments this will remove some
3110 live ranges reducing some register pressure */
3111 for (i = 0; i < count; i++)
3112 packRegisters (ebbs[i]);
3114 /* liveranges probably changed by register packing
3115 so we compute them again */
3116 recomputeLiveRanges (ebbs, count);
3118 if (options.dump_pack)
3119 dumpEbbsToFileExt (DUMP_PACK, ebbs, count);
3121 /* first determine for each live range the number of
3122 registers & the type of registers required for each */
3125 /* and serially allocate registers */
3126 serialRegAssign (ebbs, count);
3133 /* if stack was extended then tell the user */
3136 /* werror(W_TOOMANY_SPILS,"stack", */
3137 /* _G.stackExtend,currFunc->name,""); */
3143 /* werror(W_TOOMANY_SPILS,"data space", */
3144 /* _G.dataExtend,currFunc->name,""); */
3148 /* after that create the register mask
3149 for each of the instruction */
3150 createRegMask (ebbs, count);
3152 /* redo that offsets for stacked automatic variables */
3154 redoStackOffsets ();
3156 if (options.dump_rassgn) {
3157 dumpEbbsToFileExt (DUMP_RASSGN, ebbs, count);
3158 dumpLiveRanges (DUMP_LRANGE, liveRanges);
3161 /* do the overlaysegment stuff SDCCmem.c */
3162 doOverlays (ebbs, count);
3164 /* now get back the chain */
3165 ic = iCodeLabelOptimize (iCodeFromeBBlock (ebbs, count));
3170 /* free up any _G.stackSpil locations allocated */
3171 applyToSet (_G.stackSpil, deallocStackSpil);
3173 setToNull ((void *) &_G.stackSpil);
3174 setToNull ((void *) &_G.spiltSet);
3175 /* mark all registers as free */