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 genhc08Code (iCode *);
48 bitVect *totRegAssigned; /* final set of LRs that got into registers */
51 bitVect *funcrUsed; /* registers used in a function */
57 /* Shared with gen.c */
58 int hc08_ptrRegReq; /* one byte pointer register required */
64 {REG_GPR, A_IDX, REG_GPR, "a", "a", "0", 1, NULL, 0, 1},
65 {REG_GPR, X_IDX, REG_GPR, "x", "x", "0", 2, NULL, 0, 1},
66 {REG_GPR, H_IDX, REG_GPR, "h", "h", "0", 4, NULL, 0, 1},
67 {REG_PTR, HX_IDX, REG_PTR, "hx", "hx", "0", 6, NULL, 0, 1},
68 {REG_GPR, XA_IDX, REG_GPR, "xa", "xa", "0", 3, NULL, 0, 1},
70 {REG_CND, CND_IDX, REG_CND, "C", "C", "xreg", 0, NULL, 0, 1},
80 static void spillThis (symbol *);
81 static void freeAllRegs ();
83 /*-----------------------------------------------------------------*/
84 /* allocReg - allocates register of given type */
85 /*-----------------------------------------------------------------*/
91 if ((type==REG_PTR) && (regshc08[HX_IDX].isFree))
93 regshc08[HX_IDX].isFree = 0;
96 bitVectSetBit (currFunc->regsUsed, HX_IDX);
97 return ®shc08[HX_IDX];
102 /*-----------------------------------------------------------------*/
103 /* hc08_regWithIdx - returns pointer to register wit index number */
104 /*-----------------------------------------------------------------*/
106 hc08_regWithIdx (int idx)
110 for (i = 0; i < hc08_nRegs; i++)
111 if (regshc08[i].rIdx == idx)
114 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
115 "regWithIdx not found");
119 /*-----------------------------------------------------------------*/
120 /* hc08_freeReg - frees a register */
121 /*-----------------------------------------------------------------*/
123 hc08_freeReg (regs * reg)
127 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
128 "hc08_freeReg - Freeing NULL register");
137 if (hc08_reg_x->isFree)
138 hc08_reg_xa->isFree = 1;
141 if (hc08_reg_a->isFree)
142 hc08_reg_xa->isFree = 1;
143 if (hc08_reg_h->isFree)
144 hc08_reg_hx->isFree = 1;
147 if (hc08_reg_x->isFree)
148 hc08_reg_hx->isFree = 1;
151 hc08_reg_h->isFree = 1;
152 hc08_reg_x->isFree = 1;
153 if (hc08_reg_a->isFree)
154 hc08_reg_xa->isFree = 1;
157 hc08_reg_x->isFree = 1;
158 hc08_reg_a->isFree = 1;
159 if (hc08_reg_h->isFree)
160 hc08_reg_hx->isFree = 1;
168 /*-----------------------------------------------------------------*/
169 /* nFreeRegs - returns number of free registers */
170 /*-----------------------------------------------------------------*/
179 for (i = 0; i < hc08_nRegs; i++)
180 if (regshc08[i].isFree && regshc08[i].type == type)
185 /*-----------------------------------------------------------------*/
186 /* nfreeRegsType - free registers with type */
187 /*-----------------------------------------------------------------*/
189 nfreeRegsType (int type)
194 if ((nfr = nFreeRegs (type)) == 0)
195 return nFreeRegs (REG_GPR);
198 return nFreeRegs (type);
201 /*-----------------------------------------------------------------*/
202 /* hc08_useReg - marks a register as used */
203 /*-----------------------------------------------------------------*/
205 hc08_useReg (regs * reg)
212 hc08_reg_xa->aop = NULL;
213 hc08_reg_xa->isFree = 0;
216 hc08_reg_xa->aop = NULL;
217 hc08_reg_xa->isFree = 0;
218 hc08_reg_hx->aop = NULL;
219 hc08_reg_hx->isFree = 0;
222 hc08_reg_hx->aop = NULL;
223 hc08_reg_hx->isFree = 0;
226 hc08_reg_h->aop = NULL;
227 hc08_reg_h->isFree = 0;
228 hc08_reg_x->aop = NULL;
229 hc08_reg_x->isFree = 0;
232 hc08_reg_x->aop = NULL;
233 hc08_reg_x->isFree = 0;
234 hc08_reg_a->aop = NULL;
235 hc08_reg_a->isFree = 0;
243 /*-----------------------------------------------------------------*/
244 /* hc08_dirtyReg - marks a register as dirty */
245 /*-----------------------------------------------------------------*/
247 hc08_dirtyReg (regs * reg, bool freereg)
254 hc08_reg_xa->aop = NULL;
257 hc08_reg_xa->aop = NULL;
258 hc08_reg_hx->aop = NULL;
261 hc08_reg_hx->aop = NULL;
264 hc08_reg_h->aop = NULL;
265 hc08_reg_x->aop = NULL;
268 hc08_reg_x->aop = NULL;
269 hc08_reg_a->aop = NULL;
278 /*-----------------------------------------------------------------*/
279 /* computeSpillable - given a point find the spillable live ranges */
280 /*-----------------------------------------------------------------*/
282 computeSpillable (iCode * ic)
286 /* spillable live ranges are those that are live at this
287 point . the following categories need to be subtracted
289 a) - those that are already spilt
290 b) - if being used by this one
291 c) - defined by this one */
293 spillable = bitVectCopy (ic->rlive);
295 bitVectCplAnd (spillable, _G.spiltSet); /* those already spilt */
297 bitVectCplAnd (spillable, ic->uses); /* used in this one */
298 bitVectUnSetBit (spillable, ic->defKey);
299 spillable = bitVectIntersect (spillable, _G.regAssigned);
304 /*-----------------------------------------------------------------*/
305 /* noSpilLoc - return true if a variable has no spil location */
306 /*-----------------------------------------------------------------*/
308 noSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
310 return (sym->usl.spillLoc ? 0 : 1);
313 /*-----------------------------------------------------------------*/
314 /* hasSpilLoc - will return 1 if the symbol has spil location */
315 /*-----------------------------------------------------------------*/
317 hasSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
319 return (sym->usl.spillLoc ? 1 : 0);
322 /*-----------------------------------------------------------------*/
323 /* directSpilLoc - will return 1 if the splilocation is in direct */
324 /*-----------------------------------------------------------------*/
326 directSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
328 if (sym->usl.spillLoc &&
329 (IN_DIRSPACE (SPEC_OCLS (sym->usl.spillLoc->etype))))
335 /*-----------------------------------------------------------------*/
336 /* hasSpilLocnoUptr - will return 1 if the symbol has spil location */
337 /* but is not used as a pointer */
338 /*-----------------------------------------------------------------*/
340 hasSpilLocnoUptr (symbol * sym, eBBlock * ebp, iCode * ic)
342 return ((sym->usl.spillLoc && !sym->uptr) ? 1 : 0);
345 /*-----------------------------------------------------------------*/
346 /* rematable - will return 1 if the remat flag is set */
347 /*-----------------------------------------------------------------*/
349 rematable (symbol * sym, eBBlock * ebp, iCode * ic)
354 /*-----------------------------------------------------------------*/
355 /* notUsedInRemaining - not used or defined in remain of the block */
356 /*-----------------------------------------------------------------*/
358 notUsedInRemaining (symbol * sym, eBBlock * ebp, iCode * ic)
360 return ((usedInRemaining (operandFromSymbol (sym), ic) ? 0 : 1) &&
361 allDefsOutOfRange (sym->defs, ebp->fSeq, ebp->lSeq));
364 /*-----------------------------------------------------------------*/
365 /* allLRs - return true for all */
366 /*-----------------------------------------------------------------*/
368 allLRs (symbol * sym, eBBlock * ebp, iCode * ic)
373 /*-----------------------------------------------------------------*/
374 /* liveRangesWith - applies function to a given set of live range */
375 /*-----------------------------------------------------------------*/
377 liveRangesWith (bitVect * lrs, int (func) (symbol *, eBBlock *, iCode *),
378 eBBlock * ebp, iCode * ic)
383 if (!lrs || !lrs->size)
386 for (i = 1; i < lrs->size; i++)
389 if (!bitVectBitValue (lrs, i))
392 /* if we don't find it in the live range
393 hash table we are in serious trouble */
394 if (!(sym = hTabItemWithKey (liveRanges, i)))
396 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
397 "liveRangesWith could not find liveRange");
401 if (func (sym, ebp, ic) && bitVectBitValue (_G.regAssigned, sym->key))
402 addSetHead (&rset, sym);
409 /*-----------------------------------------------------------------*/
410 /* leastUsedLR - given a set determines which is the least used */
411 /*-----------------------------------------------------------------*/
413 leastUsedLR (set * sset)
415 symbol *sym = NULL, *lsym = NULL;
417 sym = lsym = setFirstItem (sset);
422 for (; lsym; lsym = setNextItem (sset))
425 /* if usage is the same then prefer
426 the spill the smaller of the two */
427 if (lsym->used == sym->used)
428 if (getSize (lsym->type) < getSize (sym->type))
432 if (lsym->used < sym->used)
437 setToNull ((void **) &sset);
442 /*-----------------------------------------------------------------*/
443 /* noOverLap - will iterate through the list looking for over lap */
444 /*-----------------------------------------------------------------*/
446 noOverLap (set * itmpStack, symbol * fsym)
451 for (sym = setFirstItem (itmpStack); sym;
452 sym = setNextItem (itmpStack))
454 if (bitVectBitValue(sym->clashes,fsym->key)) return 0;
460 /*-----------------------------------------------------------------*/
461 /* isFree - will return 1 if the a free spil location is found */
462 /*-----------------------------------------------------------------*/
467 V_ARG (symbol **, sloc);
468 V_ARG (symbol *, fsym);
470 /* if already found */
474 /* if it is free && and the itmp assigned to
475 this does not have any overlapping live ranges
476 with the one currently being assigned and
477 the size can be accomodated */
479 noOverLap (sym->usl.itmpStack, fsym) &&
480 getSize (sym->type) >= getSize (fsym->type))
489 /*-----------------------------------------------------------------*/
490 /* spillLRWithPtrReg :- will spil those live ranges which use PTR */
491 /*-----------------------------------------------------------------*/
493 spillLRWithPtrReg (symbol * forSym)
499 if (!_G.regAssigned ||
500 bitVectIsZero (_G.regAssigned))
503 hx = hc08_regWithIdx (HX_IDX);
505 /* for all live ranges */
506 for (lrsym = hTabFirstItem (liveRanges, &k); lrsym;
507 lrsym = hTabNextItem (liveRanges, &k))
511 /* if no registers assigned to it or spilt */
512 /* if it does not overlap with this then
513 not need to spill it */
515 if (lrsym->isspilt || !lrsym->nRegs ||
516 (lrsym->liveTo < forSym->liveFrom))
519 /* go thru the registers : if it is either
520 r0 or r1 then spil it */
521 for (j = 0; j < lrsym->nRegs; j++)
522 if (lrsym->regs[j] == hx)
531 /*-----------------------------------------------------------------*/
532 /* createStackSpil - create a location on the stack to spil */
533 /*-----------------------------------------------------------------*/
535 createStackSpil (symbol * sym)
538 int useXstack, model;
542 /* first go try and find a free one that is already
543 existing on the stack */
544 if (applyToSet (_G.stackSpil, isFree, &sloc, sym))
546 /* found a free one : just update & return */
547 sym->usl.spillLoc = sloc;
550 addSetHead (&sloc->usl.itmpStack, sym);
554 /* could not then have to create one , this is the hard part
555 we need to allocate this on the stack : this is really a
556 hack!! but cannot think of anything better at this time */
558 if (sprintf (slocBuffer, "sloc%d", _G.slocNum++) >= sizeof (slocBuffer))
560 fprintf (stderr, "***Internal error: slocBuffer overflowed: %s:%d\n",
565 sloc = newiTemp (slocBuffer);
567 /* set the type to the spilling symbol */
568 sloc->type = copyLinkChain (sym->type);
569 sloc->etype = getSpec (sloc->type);
570 SPEC_SCLS (sloc->etype) = S_DATA;
571 SPEC_EXTR (sloc->etype) = 0;
572 SPEC_STAT (sloc->etype) = 0;
573 SPEC_VOLATILE(sloc->etype) = 0;
574 SPEC_ABSA(sloc->etype) = 0;
576 /* we don't allow it to be allocated`
577 onto the external stack since : so we
578 temporarily turn it off ; we also
579 turn off memory model to prevent
580 the spil from going to the external storage
583 useXstack = options.useXstack;
584 model = options.model;
585 /* noOverlay = options.noOverlay; */
586 /* options.noOverlay = 1; */
587 options.model = options.useXstack = 0;
591 options.useXstack = useXstack;
592 options.model = model;
593 /* options.noOverlay = noOverlay; */
594 sloc->isref = 1; /* to prevent compiler warning */
596 /* if it is on the stack then update the stack */
597 if (IN_STACK (sloc->etype))
599 currFunc->stack += getSize (sloc->type);
600 _G.stackExtend += getSize (sloc->type);
603 _G.dataExtend += getSize (sloc->type);
605 /* add it to the _G.stackSpil set */
606 addSetHead (&_G.stackSpil, sloc);
607 sym->usl.spillLoc = sloc;
610 /* add it to the set of itempStack set
611 of the spill location */
612 addSetHead (&sloc->usl.itmpStack, sym);
616 /*-----------------------------------------------------------------*/
617 /* isSpiltOnStack - returns true if the spil location is on stack */
618 /*-----------------------------------------------------------------*/
620 isSpiltOnStack (symbol * sym)
630 /* if (sym->_G.stackSpil) */
633 if (!sym->usl.spillLoc)
636 etype = getSpec (sym->usl.spillLoc->type);
637 if (IN_STACK (etype))
643 /*-----------------------------------------------------------------*/
644 /* spillThis - spils a specific operand */
645 /*-----------------------------------------------------------------*/
647 spillThis (symbol * sym)
650 /* if this is rematerializable or has a spillLocation
651 we are okay, else we need to create a spillLocation
653 if (!(sym->remat || sym->usl.spillLoc))
654 createStackSpil (sym);
656 /* mark it has spilt & put it in the spilt set */
657 sym->isspilt = sym->spillA = 1;
658 _G.spiltSet = bitVectSetBit (_G.spiltSet, sym->key);
660 bitVectUnSetBit (_G.regAssigned, sym->key);
661 bitVectUnSetBit (_G.totRegAssigned, sym->key);
663 for (i = 0; i < sym->nRegs; i++)
667 hc08_freeReg (sym->regs[i]);
671 /* if spilt on stack then free up r0 & r1
672 if they could have been assigned to some
674 // if (!hc08_ptrRegReq && isSpiltOnStack (sym))
677 // spillLRWithPtrReg (sym);
680 if (sym->usl.spillLoc && !sym->remat)
681 sym->usl.spillLoc->allocreq++;
685 /*-----------------------------------------------------------------*/
686 /* selectSpil - select a iTemp to spil : rather a simple procedure */
687 /*-----------------------------------------------------------------*/
689 selectSpil (iCode * ic, eBBlock * ebp, symbol * forSym)
691 bitVect *lrcs = NULL;
695 /* get the spillable live ranges */
696 lrcs = computeSpillable (ic);
698 /* get all live ranges that are rematerizable */
699 if ((selectS = liveRangesWith (lrcs, rematable, ebp, ic)))
702 /* return the least used of these */
703 return leastUsedLR (selectS);
706 /* get live ranges with spillLocations in direct space */
707 if ((selectS = liveRangesWith (lrcs, directSpilLoc, ebp, ic)))
709 sym = leastUsedLR (selectS);
710 strcpy (sym->rname, (sym->usl.spillLoc->rname[0] ?
711 sym->usl.spillLoc->rname :
712 sym->usl.spillLoc->name));
714 /* mark it as allocation required */
715 sym->usl.spillLoc->allocreq++;
719 /* if the symbol is local to the block then */
720 if (forSym->liveTo < ebp->lSeq)
723 /* check if there are any live ranges allocated
724 to registers that are not used in this block */
725 if (!_G.blockSpil && (selectS = liveRangesWith (lrcs, notUsedInBlock, ebp, ic)))
727 sym = leastUsedLR (selectS);
728 /* if this is not rematerializable */
737 /* check if there are any live ranges that not
738 used in the remainder of the block */
739 if (!_G.blockSpil && (selectS = liveRangesWith (lrcs, notUsedInRemaining, ebp, ic)))
741 sym = leastUsedLR (selectS);
754 /* find live ranges with spillocation && not used as pointers */
755 if ((selectS = liveRangesWith (lrcs, hasSpilLocnoUptr, ebp, ic)))
758 sym = leastUsedLR (selectS);
759 /* mark this as allocation required */
760 sym->usl.spillLoc->allocreq++;
764 /* find live ranges with spillocation */
765 if ((selectS = liveRangesWith (lrcs, hasSpilLoc, ebp, ic)))
768 sym = leastUsedLR (selectS);
769 sym->usl.spillLoc->allocreq++;
773 /* couldn't find then we need to create a spil
774 location on the stack , for which one? the least
776 if ((selectS = liveRangesWith (lrcs, noSpilLoc, ebp, ic)))
779 /* return a created spil location */
780 sym = createStackSpil (leastUsedLR (selectS));
781 sym->usl.spillLoc->allocreq++;
785 /* this is an extreme situation we will spill
786 this one : happens very rarely but it does happen */
792 /*-----------------------------------------------------------------*/
793 /* spilSomething - spil some variable & mark registers as free */
794 /*-----------------------------------------------------------------*/
796 spilSomething (iCode * ic, eBBlock * ebp, symbol * forSym)
801 /* get something we can spil */
802 ssym = selectSpil (ic, ebp, forSym);
804 /* mark it as spilt */
805 ssym->isspilt = ssym->spillA = 1;
806 _G.spiltSet = bitVectSetBit (_G.spiltSet, ssym->key);
808 /* mark it as not register assigned &
809 take it away from the set */
810 bitVectUnSetBit (_G.regAssigned, ssym->key);
811 bitVectUnSetBit (_G.totRegAssigned, ssym->key);
813 /* mark the registers as free */
814 for (i = 0; i < ssym->nRegs; i++)
816 hc08_freeReg (ssym->regs[i]);
818 /* if spilt on stack then free up hx
819 if it could have been assigned to as gprs */
820 if (!hc08_ptrRegReq && isSpiltOnStack (ssym))
823 spillLRWithPtrReg (ssym);
826 /* if this was a block level spil then insert push & pop
827 at the start & end of block respectively */
830 iCode *nic = newiCode (IPUSH, operandFromSymbol (ssym), NULL);
831 /* add push to the start of the block */
832 addiCodeToeBBlock (ebp, nic, (ebp->sch->op == LABEL ?
833 ebp->sch->next : ebp->sch));
834 nic = newiCode (IPOP, operandFromSymbol (ssym), NULL);
835 /* add pop to the end of the block */
836 addiCodeToeBBlock (ebp, nic, NULL);
839 /* if spilt because not used in the remainder of the
840 block then add a push before this instruction and
841 a pop at the end of the block */
842 if (ssym->remainSpil)
845 iCode *nic = newiCode (IPUSH, operandFromSymbol (ssym), NULL);
846 /* add push just before this instruction */
847 addiCodeToeBBlock (ebp, nic, ic);
849 nic = newiCode (IPOP, operandFromSymbol (ssym), NULL);
850 /* add pop to the end of the block */
851 addiCodeToeBBlock (ebp, nic, NULL);
860 /*-----------------------------------------------------------------*/
861 /* getRegPtr - will try for PTR if not a GPR type if not spil */
862 /*-----------------------------------------------------------------*/
864 getRegPtr (iCode * ic, eBBlock * ebp, symbol * sym)
869 /* try for a ptr type */
870 if ((reg = allocReg (REG_PTR)))
873 /* try for gpr type */
874 if ((reg = allocReg (REG_GPR)))
877 /* we have to spil */
878 if (!spilSomething (ic, ebp, sym))
881 /* this looks like an infinite loop but
882 in really selectSpil will abort */
886 /*-----------------------------------------------------------------*/
887 /* getRegGpr - will try for GPR if not spil */
888 /*-----------------------------------------------------------------*/
890 getRegGpr (iCode * ic, eBBlock * ebp, symbol * sym)
895 /* try for gpr type */
896 if ((reg = allocReg (REG_GPR)))
900 if ((reg = allocReg (REG_PTR)))
903 /* we have to spil */
904 if (!spilSomething (ic, ebp, sym))
907 /* this looks like an infinite loop but
908 in really selectSpil will abort */
912 /*-----------------------------------------------------------------*/
913 /* getRegPtrNoSpil - get it cannot split */
914 /*-----------------------------------------------------------------*/
915 static regs *getRegPtrNoSpil()
919 /* try for a ptr type */
920 if ((reg = allocReg (REG_PTR)))
923 /* try for gpr type */
924 if ((reg = allocReg (REG_GPR)))
929 /* just to make the compiler happy */
933 /*-----------------------------------------------------------------*/
934 /* getRegGprNoSpil - get it cannot split */
935 /*-----------------------------------------------------------------*/
936 static regs *getRegGprNoSpil()
940 if ((reg = allocReg (REG_GPR)))
944 if ((reg = allocReg (REG_PTR)))
949 /* just to make the compiler happy */
953 /*-----------------------------------------------------------------*/
954 /* symHasReg - symbol has a given register */
955 /*-----------------------------------------------------------------*/
957 symHasReg (symbol * sym, regs * reg)
961 for (i = 0; i < sym->nRegs; i++)
962 if (sym->regs[i] == reg)
968 /*-----------------------------------------------------------------*/
969 /* deassignLRs - check the live to and if they have registers & are */
970 /* not spilt then free up the registers */
971 /*-----------------------------------------------------------------*/
973 deassignLRs (iCode * ic, eBBlock * ebp)
979 for (sym = hTabFirstItem (liveRanges, &k); sym;
980 sym = hTabNextItem (liveRanges, &k))
984 /* if it does not end here */
985 if (sym->liveTo > ic->seq)
988 /* if it was spilt on stack then we can
989 mark the stack spil location as free */
994 sym->usl.spillLoc->isFree = 1;
1000 if (!bitVectBitValue (_G.regAssigned, sym->key))
1003 /* special case check if this is an IFX &
1004 the privious one was a pop and the
1005 previous one was not spilt then keep track
1007 if (ic->op == IFX && ic->prev &&
1008 ic->prev->op == IPOP &&
1009 !ic->prev->parmPush &&
1010 !OP_SYMBOL (IC_LEFT (ic->prev))->isspilt)
1011 psym = OP_SYMBOL (IC_LEFT (ic->prev));
1017 bitVectUnSetBit (_G.regAssigned, sym->key);
1019 /* if the result of this one needs registers
1020 and does not have it then assign it right
1022 if (IC_RESULT (ic) &&
1023 !(SKIP_IC2 (ic) || /* not a special icode */
1024 ic->op == JUMPTABLE ||
1029 POINTER_SET (ic)) &&
1030 (result = OP_SYMBOL (IC_RESULT (ic))) && /* has a result */
1031 result->liveTo > ic->seq && /* and will live beyond this */
1032 result->liveTo <= ebp->lSeq && /* does not go beyond this block */
1033 result->regType == sym->regType && /* same register types */
1034 result->nRegs && /* which needs registers */
1035 !result->isspilt && /* and does not already have them */
1037 !bitVectBitValue (_G.regAssigned, result->key) &&
1038 /* the number of free regs + number of regs in this LR
1039 can accomodate the what result Needs */
1040 ((nfreeRegsType (result->regType) +
1041 sym->nRegs) >= result->nRegs)
1045 for (i = 0; i < result->nRegs; i++)
1047 result->regs[i] = sym->regs[i];
1049 result->regs[i] = getRegGpr (ic, ebp, result);
1051 _G.regAssigned = bitVectSetBit (_G.regAssigned, result->key);
1052 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, result->key);
1056 /* free the remaining */
1057 for (; i < sym->nRegs; i++)
1061 if (!symHasReg (psym, sym->regs[i]))
1062 hc08_freeReg (sym->regs[i]);
1065 hc08_freeReg (sym->regs[i]);
1072 /*-----------------------------------------------------------------*/
1073 /* reassignLR - reassign this to registers */
1074 /*-----------------------------------------------------------------*/
1076 reassignLR (operand * op)
1078 symbol *sym = OP_SYMBOL (op);
1081 /* not spilt any more */
1082 sym->isspilt = sym->spillA = sym->blockSpil = sym->remainSpil = 0;
1083 bitVectUnSetBit (_G.spiltSet, sym->key);
1085 _G.regAssigned = bitVectSetBit (_G.regAssigned, sym->key);
1086 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, sym->key);
1090 for (i = 0; i < sym->nRegs; i++)
1091 sym->regs[i]->isFree = 0;
1094 /*-----------------------------------------------------------------*/
1095 /* willCauseSpill - determines if allocating will cause a spill */
1096 /*-----------------------------------------------------------------*/
1098 willCauseSpill (int nr, int rt)
1100 /* first check if there are any avlb registers
1101 of te type required */
1104 /* special case for pointer type
1105 if pointer type not avlb then
1106 check for type gpr */
1107 if (nFreeRegs (rt) >= nr)
1109 if (nFreeRegs (REG_GPR) >= nr)
1116 if (nFreeRegs (rt) >= nr)
1121 if (nFreeRegs (REG_PTR) +
1122 nFreeRegs (REG_GPR) >= nr)
1127 /* it will cause a spil */
1131 /*-----------------------------------------------------------------*/
1132 /* positionRegs - the allocator can allocate same registers to res- */
1133 /* ult and operand, if this happens make sure they are in the same */
1134 /* position as the operand otherwise chaos results */
1135 /*-----------------------------------------------------------------*/
1137 positionRegs (symbol * result, symbol * opsym)
1139 int count = min (result->nRegs, opsym->nRegs);
1140 int i, j = 0, shared = 0;
1143 /* if the result has been spilt then cannot share */
1148 /* first make sure that they actually share */
1149 for (i = 0; i < count; i++)
1151 for (j = 0; j < count; j++)
1153 if (result->regs[i] == opsym->regs[j] && i != j)
1163 regs *tmp = result->regs[i];
1164 result->regs[i] = result->regs[j];
1165 result->regs[j] = tmp;
1172 /*-----------------------------------------------------------------*/
1173 /* serialRegAssign - serially allocate registers to the variables */
1174 /*-----------------------------------------------------------------*/
1176 serialRegAssign (eBBlock ** ebbs, int count)
1180 /* for all blocks */
1181 for (i = 0; i < count; i++) {
1185 if (ebbs[i]->noPath &&
1186 (ebbs[i]->entryLabel != entryLabel &&
1187 ebbs[i]->entryLabel != returnLabel))
1190 /* of all instructions do */
1191 for (ic = ebbs[i]->sch; ic; ic = ic->next) {
1195 // update the registers in use at the start of this icode
1196 for (reg=0; reg<hc08_nRegs; reg++) {
1197 if (regshc08[reg].isFree) {
1198 ic->riu &= ~(regshc08[reg].mask);
1200 ic->riu |= (regshc08[reg].mask);
1205 /* if this is an ipop that means some live
1206 range will have to be assigned again */
1208 reassignLR (IC_LEFT (ic));
1210 /* if result is present && is a true symbol */
1211 if (IC_RESULT (ic) && ic->op != IFX &&
1212 IS_TRUE_SYMOP (IC_RESULT (ic)))
1213 OP_SYMBOL (IC_RESULT (ic))->allocreq++;
1215 /* take away registers from live
1216 ranges that end at this instruction */
1217 deassignLRs (ic, ebbs[i]);
1219 /* some don't need registers */
1220 if (SKIP_IC2 (ic) ||
1221 ic->op == JUMPTABLE ||
1225 (IC_RESULT (ic) && POINTER_SET (ic)))
1228 /* now we need to allocate registers
1229 only for the result */
1230 if (IC_RESULT (ic)) {
1231 symbol *sym = OP_SYMBOL (IC_RESULT (ic));
1237 /* if it does not need or is spilt
1238 or is already assigned to registers
1239 or will not live beyond this instructions */
1242 bitVectBitValue (_G.regAssigned, sym->key) ||
1243 sym->liveTo <= ic->seq)
1246 /* if some liverange has been spilt at the block level
1247 and this one live beyond this block then spil this
1249 if (_G.blockSpil && sym->liveTo > ebbs[i]->lSeq) {
1253 /* if trying to allocate this will cause
1254 a spill and there is nothing to spill
1255 or this one is rematerializable then
1257 willCS = willCauseSpill (sym->nRegs, sym->regType);
1258 spillable = computeSpillable (ic);
1259 if (sym->remat || (willCS && bitVectIsZero (spillable))) {
1264 /* if it has a spillocation & is used less than
1265 all other live ranges then spill this */
1267 if (sym->usl.spillLoc) {
1268 symbol *leastUsed = leastUsedLR (liveRangesWith (spillable,
1269 allLRs, ebbs[i], ic));
1270 if (leastUsed && leastUsed->used > sym->used) {
1275 /* if none of the liveRanges have a spillLocation then better
1276 to spill this one than anything else already assigned to registers */
1277 if (liveRangesWith(spillable,noSpilLoc,ebbs[i],ic)) {
1278 /* if this is local to this block then we might find a block spil */
1279 if (!(sym->liveFrom >= ebbs[i]->fSeq && sym->liveTo <= ebbs[i]->lSeq)) {
1286 /* if we need ptr regs for the right side
1288 if (POINTER_GET (ic) && IS_SYMOP (IC_LEFT (ic))
1289 && getSize (OP_SYMBOL (IC_LEFT (ic))->type) <= (unsigned int) PTRSIZE) {
1293 /* else we assign registers to it */
1294 _G.regAssigned = bitVectSetBit (_G.regAssigned, sym->key);
1295 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, sym->key);
1297 for (j = 0; j < sym->nRegs; j++) {
1298 if (sym->regType == REG_PTR)
1299 sym->regs[j] = getRegPtr (ic, ebbs[i], sym);
1301 sym->regs[j] = getRegGpr (ic, ebbs[i], sym);
1303 /* if the allocation failed which means
1304 this was spilt then break */
1305 if (!sym->regs[j]) {
1310 /* if it shares registers with operands make sure
1311 that they are in the same position */
1312 if (IC_LEFT (ic) && IS_SYMOP (IC_LEFT (ic)) &&
1313 OP_SYMBOL (IC_LEFT (ic))->nRegs && ic->op != '=') {
1314 positionRegs (OP_SYMBOL (IC_RESULT (ic)),
1315 OP_SYMBOL (IC_LEFT (ic)));
1317 /* do the same for the right operand */
1318 if (IC_RIGHT (ic) && IS_SYMOP (IC_RIGHT (ic)) &&
1319 OP_SYMBOL (IC_RIGHT (ic))->nRegs) {
1320 positionRegs (OP_SYMBOL (IC_RESULT (ic)),
1321 OP_SYMBOL (IC_RIGHT (ic)));
1334 /*-----------------------------------------------------------------*/
1335 /* fillGaps - Try to fill in the Gaps left by Pass1 */
1336 /*-----------------------------------------------------------------*/
1337 static void fillGaps()
1342 if (getenv("DISABLE_FILL_GAPS")) return;
1344 /* look for livernages that was spilt by the allocator */
1345 for (sym = hTabFirstItem(liveRanges,&key) ; sym ;
1346 sym = hTabNextItem(liveRanges,&key)) {
1351 if (!sym->spillA || !sym->clashes || sym->remat) continue ;
1353 /* find the liveRanges this one clashes with, that are
1354 still assigned to registers & mark the registers as used*/
1355 for ( i = 0 ; i < sym->clashes->size ; i ++) {
1359 if (bitVectBitValue(sym->clashes,i) == 0 || /* those that clash with this */
1360 bitVectBitValue(_G.totRegAssigned,i) == 0) /* and are still assigned to registers */
1363 clr = hTabItemWithKey(liveRanges,i);
1366 /* mark these registers as used */
1367 for (k = 0 ; k < clr->nRegs ; k++ )
1368 hc08_useReg(clr->regs[k]);
1371 if (willCauseSpill(sym->nRegs,sym->regType)) {
1372 /* NOPE :( clear all registers & and continue */
1377 /* THERE IS HOPE !!!! */
1378 for (i=0; i < sym->nRegs ; i++ ) {
1379 if (sym->regType == REG_PTR)
1380 sym->regs[i] = getRegPtrNoSpil ();
1382 sym->regs[i] = getRegGprNoSpil ();
1385 /* for all its definitions check if the registers
1386 allocated needs positioning NOTE: we can position
1387 only ONCE if more than One positioning required
1390 for (i = 0 ; i < sym->defs->size ; i++ ) {
1391 if (bitVectBitValue(sym->defs,i)) {
1393 if (!(ic = hTabItemWithKey(iCodehTab,i))) continue ;
1394 if (SKIP_IC(ic)) continue;
1395 assert(isSymbolEqual(sym,OP_SYMBOL(IC_RESULT(ic)))); /* just making sure */
1396 /* if left is assigned to registers */
1397 if (IS_SYMOP(IC_LEFT(ic)) &&
1398 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_LEFT(ic))->key)) {
1399 pdone += positionRegs(sym,OP_SYMBOL(IC_LEFT(ic)));
1401 if (IS_SYMOP(IC_RIGHT(ic)) &&
1402 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_RIGHT(ic))->key)) {
1403 pdone += positionRegs(sym,OP_SYMBOL(IC_RIGHT(ic)));
1405 if (pdone > 1) break;
1408 for (i = 0 ; i < sym->uses->size ; i++ ) {
1409 if (bitVectBitValue(sym->uses,i)) {
1411 if (!(ic = hTabItemWithKey(iCodehTab,i))) continue ;
1412 if (SKIP_IC(ic)) continue;
1413 if (!IS_ASSIGN_ICODE(ic)) continue ;
1415 /* if result is assigned to registers */
1416 if (IS_SYMOP(IC_RESULT(ic)) &&
1417 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_RESULT(ic))->key)) {
1418 pdone += positionRegs(sym,OP_SYMBOL(IC_RESULT(ic)));
1420 if (pdone > 1) break;
1423 /* had to position more than once GIVE UP */
1425 /* UNDO all the changes we made to try this */
1427 for (i=0; i < sym->nRegs ; i++ ) {
1428 sym->regs[i] = NULL;
1431 D(printf ("Fill Gap gave up due to positioning for %s in function %s\n",sym->name, currFunc ? currFunc->name : "UNKNOWN"));
1434 D(printf ("FILLED GAP for %s in function %s\n",sym->name, currFunc ? currFunc->name : "UNKNOWN"));
1435 _G.totRegAssigned = bitVectSetBit(_G.totRegAssigned,sym->key);
1436 sym->isspilt = sym->spillA = 0 ;
1437 sym->usl.spillLoc->allocreq--;
1442 /*-----------------------------------------------------------------*/
1443 /* rUmaskForOp :- returns register mask for an operand */
1444 /*-----------------------------------------------------------------*/
1446 hc08_rUmaskForOp (operand * op)
1452 /* only temporaries are assigned registers */
1456 sym = OP_SYMBOL (op);
1458 /* if spilt or no registers assigned to it
1460 if (sym->isspilt || !sym->nRegs)
1463 rumask = newBitVect (hc08_nRegs);
1465 for (j = 0; j < sym->nRegs; j++)
1467 rumask = bitVectSetBit (rumask,
1468 sym->regs[j]->rIdx);
1474 /*-----------------------------------------------------------------*/
1475 /* regsUsedIniCode :- returns bit vector of registers used in iCode */
1476 /*-----------------------------------------------------------------*/
1478 regsUsedIniCode (iCode * ic)
1480 bitVect *rmask = newBitVect (hc08_nRegs);
1482 /* do the special cases first */
1485 rmask = bitVectUnion (rmask,
1486 hc08_rUmaskForOp (IC_COND (ic)));
1490 /* for the jumptable */
1491 if (ic->op == JUMPTABLE)
1493 rmask = bitVectUnion (rmask,
1494 hc08_rUmaskForOp (IC_JTCOND (ic)));
1499 /* of all other cases */
1501 rmask = bitVectUnion (rmask,
1502 hc08_rUmaskForOp (IC_LEFT (ic)));
1506 rmask = bitVectUnion (rmask,
1507 hc08_rUmaskForOp (IC_RIGHT (ic)));
1510 rmask = bitVectUnion (rmask,
1511 hc08_rUmaskForOp (IC_RESULT (ic)));
1517 /*-----------------------------------------------------------------*/
1518 /* createRegMask - for each instruction will determine the regsUsed */
1519 /*-----------------------------------------------------------------*/
1521 createRegMask (eBBlock ** ebbs, int count)
1525 /* for all blocks */
1526 for (i = 0; i < count; i++)
1530 if (ebbs[i]->noPath &&
1531 (ebbs[i]->entryLabel != entryLabel &&
1532 ebbs[i]->entryLabel != returnLabel))
1535 /* for all instructions */
1536 for (ic = ebbs[i]->sch; ic; ic = ic->next)
1541 if (SKIP_IC2 (ic) || !ic->rlive)
1544 /* first mark the registers used in this
1546 ic->rUsed = regsUsedIniCode (ic);
1547 _G.funcrUsed = bitVectUnion (_G.funcrUsed, ic->rUsed);
1549 /* now create the register mask for those
1550 registers that are in use : this is a
1551 super set of ic->rUsed */
1552 ic->rMask = newBitVect (hc08_nRegs + 1);
1554 /* for all live Ranges alive at this point */
1555 for (j = 1; j < ic->rlive->size; j++)
1560 /* if not alive then continue */
1561 if (!bitVectBitValue (ic->rlive, j))
1564 /* find the live range we are interested in */
1565 if (!(sym = hTabItemWithKey (liveRanges, j)))
1567 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
1568 "createRegMask cannot find live range");
1569 fprintf(stderr, "\tmissing live range: key=%d\n", j);
1573 /* if no register assigned to it */
1574 if (!sym->nRegs || sym->isspilt)
1577 /* for all the registers allocated to it */
1578 for (k = 0; k < sym->nRegs; k++)
1581 bitVectSetBit (ic->rMask, sym->regs[k]->rIdx);
1587 /*-----------------------------------------------------------------*/
1588 /* rematStr - returns the rematerialized string for a remat var */
1589 /*-----------------------------------------------------------------*/
1591 rematStr (symbol * sym)
1594 iCode *ic = sym->rematiCode;
1600 /* if plus or minus print the right hand side */
1601 if (ic->op == '+' || ic->op == '-')
1603 sprintf (s, "0x%04x %c ", (int) operandLitValue (IC_RIGHT (ic)),
1606 ic = OP_SYMBOL (IC_LEFT (ic))->rematiCode;
1612 offset += operandLitValue (IC_RIGHT (ic));
1613 ic = OP_SYMBOL (IC_LEFT (ic))->rematiCode;
1618 offset -= operandLitValue (IC_RIGHT (ic));
1619 ic = OP_SYMBOL (IC_LEFT (ic))->rematiCode;
1623 /* cast then continue */
1624 if (IS_CAST_ICODE(ic)) {
1625 ic = OP_SYMBOL (IC_RIGHT (ic))->rematiCode;
1628 /* we reached the end */
1629 sprintf (s, "%s", OP_SYMBOL (IC_LEFT (ic))->rname);
1636 /*-----------------------------------------------------------------*/
1637 /* regTypeNum - computes the type & number of registers required */
1638 /*-----------------------------------------------------------------*/
1640 regTypeNum (eBBlock *ebbs)
1646 /* for each live range do */
1647 for (sym = hTabFirstItem (liveRanges, &k); sym;
1648 sym = hTabNextItem (liveRanges, &k))
1651 /* if used zero times then no registers needed */
1652 if ((sym->liveTo - sym->liveFrom) == 0)
1656 /* if the live range is a temporary */
1660 /* if the type is marked as a conditional */
1661 if (sym->regType == REG_CND)
1664 /* if used in return only then we don't
1666 if (sym->ruonly || sym->accuse)
1668 if (IS_AGGREGATE (sym->type) || sym->isptr)
1669 sym->type = aggrToPtr (sym->type, FALSE);
1673 /* if the symbol has only one definition &
1674 that definition is a get_pointer */
1675 if (bitVectnBitsOn (sym->defs) == 1 &&
1676 (ic = hTabItemWithKey (iCodehTab,
1677 bitVectFirstBit (sym->defs))) &&
1680 !IS_BITVAR (sym->etype))
1684 /* and that pointer is remat in data space */
1685 if (IS_SYMOP (IC_LEFT (ic)) &&
1686 OP_SYMBOL (IC_LEFT (ic))->remat &&
1687 !IS_CAST_ICODE(OP_SYMBOL (IC_LEFT (ic))->rematiCode) &&
1688 DCL_TYPE (aggrToPtr (operandType(IC_LEFT(ic)), FALSE)) == POINTER)
1690 /* create a psuedo symbol & force a spil */
1691 symbol *psym = newSymbol (rematStr (OP_SYMBOL (IC_LEFT (ic))), 1);
1692 psym->type = sym->type;
1693 psym->etype = sym->etype;
1694 strcpy (psym->rname, psym->name);
1696 sym->usl.spillLoc = psym;
1697 #if 0 // an alternative fix for bug #480076
1698 /* now this is a useless assignment to itself */
1699 remiCodeFromeBBlock (ebbs, ic);
1701 /* now this really is an assignment to itself, make it so;
1702 it will be optimized out later */
1704 ReplaceOpWithCheaperOp(&IC_RIGHT(ic), IC_RESULT(ic));
1710 /* if in data space or idata space then try to
1711 allocate pointer register */
1715 /* if not then we require registers */
1716 sym->nRegs = ((IS_AGGREGATE (sym->type) || sym->isptr) ?
1717 getSize (sym->type = aggrToPtr (sym->type, FALSE)) :
1718 getSize (sym->type));
1722 fprintf (stderr, "allocated more than 4 or 0 registers for type ");
1723 printTypeChain (sym->type, stderr);
1724 fprintf (stderr, "\n");
1727 /* determine the type of register required */
1728 if (sym->nRegs == 1 &&
1729 IS_PTR (sym->type) &&
1731 sym->regType = REG_PTR;
1733 sym->regType = REG_GPR;
1737 /* for the first run we don't provide */
1738 /* registers for true symbols we will */
1739 /* see how things go */
1745 /*-----------------------------------------------------------------*/
1746 /* freeAllRegs - mark all registers as free */
1747 /*-----------------------------------------------------------------*/
1753 for (i = 0; i < hc08_nRegs; i++) {
1754 regshc08[i].isFree = 1;
1755 regshc08[i].aop = NULL;
1759 /*-----------------------------------------------------------------*/
1760 /* deallocStackSpil - this will set the stack pointer back */
1761 /*-----------------------------------------------------------------*/
1763 DEFSETFUNC (deallocStackSpil)
1772 /*-----------------------------------------------------------------*/
1773 /* farSpacePackable - returns the packable icode for far variables */
1774 /*-----------------------------------------------------------------*/
1776 farSpacePackable (iCode * ic)
1780 /* go thru till we find a definition for the
1781 symbol on the right */
1782 for (dic = ic->prev; dic; dic = dic->prev)
1784 /* if the definition is a call then no */
1785 if ((dic->op == CALL || dic->op == PCALL) &&
1786 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1791 /* if shift by unknown amount then not */
1792 if ((dic->op == LEFT_OP || dic->op == RIGHT_OP) &&
1793 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1797 /* if pointer get and size > 1 */
1798 if (POINTER_GET (dic) &&
1799 getSize (aggrToPtr (operandType (IC_LEFT (dic)), FALSE)) > 1)
1802 if (POINTER_SET (dic) &&
1803 getSize (aggrToPtr (operandType (IC_RESULT (dic)), FALSE)) > 1)
1807 /* if any three is a true symbol in far space */
1808 if (IC_RESULT (dic) &&
1809 IS_TRUE_SYMOP (IC_RESULT (dic)) /* &&
1810 isOperandInFarSpace (IC_RESULT (dic)) */)
1813 if (IC_RIGHT (dic) &&
1814 IS_TRUE_SYMOP (IC_RIGHT (dic)) /* &&
1815 isOperandInFarSpace (IC_RIGHT (dic)) */ &&
1816 !isOperandEqual (IC_RIGHT (dic), IC_RESULT (ic)))
1819 if (IC_LEFT (dic) &&
1820 IS_TRUE_SYMOP (IC_LEFT (dic)) /* &&
1821 isOperandInFarSpace (IC_LEFT (dic)) */ &&
1822 !isOperandEqual (IC_LEFT (dic), IC_RESULT (ic)))
1825 if (isOperandEqual (IC_RIGHT (ic), IC_RESULT (dic)))
1827 if ((dic->op == LEFT_OP ||
1828 dic->op == RIGHT_OP ||
1830 IS_OP_LITERAL (IC_RIGHT (dic)))
1841 /*-----------------------------------------------------------------*/
1842 /* packRegsForAssign - register reduction for assignment */
1843 /*-----------------------------------------------------------------*/
1845 packRegsForAssign (iCode * ic, eBBlock * ebp)
1849 if (!IS_ITEMP (IC_RIGHT (ic)) ||
1850 OP_SYMBOL (IC_RIGHT (ic))->isind ||
1851 OP_LIVETO (IC_RIGHT (ic)) > ic->seq)
1857 /* if the true symbol is defined in far space or on stack
1858 then we should not since this will increase register pressure */
1860 if (isOperandInFarSpace(IC_RESULT(ic)) && !farSpacePackable(ic)) {
1865 /* find the definition of iTempNN scanning backwards if we find a
1866 a use of the true symbol in before we find the definition then
1868 for (dic = ic->prev; dic; dic = dic->prev)
1871 #if 0 /* jwk: This collides with 1.43 but I really see no need for
1872 this anymore. It fixes bug #716790 and substantially improves
1873 redundant register usage around function calls.
1876 /* if there is a function call then don't pack it */
1877 if ((dic->op == CALL || dic->op == PCALL))
1887 if (IS_TRUE_SYMOP (IC_RESULT (dic)) &&
1888 IS_OP_VOLATILE (IC_RESULT (dic)))
1894 if (IS_SYMOP (IC_RESULT (dic)) &&
1895 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1897 if (POINTER_SET (dic))
1903 if (IS_SYMOP (IC_RIGHT (dic)) &&
1904 (IC_RIGHT (dic)->key == IC_RESULT (ic)->key ||
1905 IC_RIGHT (dic)->key == IC_RIGHT (ic)->key))
1911 if (IS_SYMOP (IC_LEFT (dic)) &&
1912 (IC_LEFT (dic)->key == IC_RESULT (ic)->key ||
1913 IC_LEFT (dic)->key == IC_RIGHT (ic)->key))
1919 if (POINTER_SET (dic) &&
1920 IC_RESULT (dic)->key == IC_RESULT (ic)->key)
1928 return 0; /* did not find */
1930 /* if assignment then check that right is not a bit */
1931 if (ASSIGNMENT (dic) && !POINTER_SET (dic))
1933 sym_link *etype = operandType (IC_RIGHT (dic));
1934 if (IS_BITFIELD (etype))
1936 /* if result is a bit too then it's ok */
1937 etype = operandType (IC_RESULT (dic));
1938 if (!IS_BITFIELD (etype))
1942 /* if the result is on stack or iaccess then it must be
1943 the same atleast one of the operands */
1944 if (OP_SYMBOL (IC_RESULT (ic))->onStack ||
1945 OP_SYMBOL (IC_RESULT (ic))->iaccess)
1948 /* the operation has only one symbol
1949 operator then we can pack */
1950 if ((IC_LEFT (dic) && !IS_SYMOP (IC_LEFT (dic))) ||
1951 (IC_RIGHT (dic) && !IS_SYMOP (IC_RIGHT (dic))))
1954 if (!((IC_LEFT (dic) &&
1955 IC_RESULT (ic)->key == IC_LEFT (dic)->key) ||
1957 IC_RESULT (ic)->key == IC_RIGHT (dic)->key)))
1961 /* found the definition */
1962 /* replace the result with the result of */
1963 /* this assignment and remove this assignment */
1964 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
1965 ReplaceOpWithCheaperOp(&IC_RESULT (dic), IC_RESULT (ic));
1967 if (IS_ITEMP (IC_RESULT (dic)) && OP_SYMBOL (IC_RESULT (dic))->liveFrom > dic->seq)
1969 OP_SYMBOL (IC_RESULT (dic))->liveFrom = dic->seq;
1971 // TODO: and the otherway around?
1973 /* delete from liverange table also
1974 delete from all the points inbetween and the new
1976 for (sic = dic; sic != ic; sic = sic->next)
1978 bitVectUnSetBit (sic->rlive, IC_RESULT (ic)->key);
1979 if (IS_ITEMP (IC_RESULT (dic)))
1980 bitVectSetBit (sic->rlive, IC_RESULT (dic)->key);
1983 remiCodeFromeBBlock (ebp, ic);
1984 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
1985 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
1986 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
1991 /*------------------------------------------------------------------*/
1992 /* findAssignToSym : scanning backwards looks for first assig found */
1993 /*------------------------------------------------------------------*/
1995 findAssignToSym (operand * op, iCode * ic)
1999 /* This routine is used to find sequences like
2001 ...; (intervening ops don't use iTempAA or modify FOO)
2002 blah = blah + iTempAA;
2004 and eliminate the use of iTempAA, freeing up its register for
2009 for (dic = ic->prev; dic; dic = dic->prev)
2012 /* if definition by assignment */
2013 if (dic->op == '=' &&
2014 !POINTER_SET (dic) &&
2015 IC_RESULT (dic)->key == op->key
2016 && IS_TRUE_SYMOP(IC_RIGHT(dic))
2018 break; /* found where this temp was defined */
2020 /* if we find an usage then we cannot delete it */
2021 if (IC_LEFT (dic) && IC_LEFT (dic)->key == op->key)
2024 if (IC_RIGHT (dic) && IC_RIGHT (dic)->key == op->key)
2027 if (POINTER_SET (dic) && IC_RESULT (dic)->key == op->key)
2032 return NULL; /* didn't find any assignment to op */
2034 /* we are interested only if defined in far space */
2035 /* or in stack space in case of + & - */
2037 /* if assigned to a non-symbol then don't repack regs */
2038 if (!IS_SYMOP (IC_RIGHT (dic)))
2041 /* if the symbol is volatile then we should not */
2042 if (isOperandVolatile (IC_RIGHT (dic), TRUE))
2044 /* XXX TODO --- should we be passing FALSE to isOperandVolatile()?
2045 What does it mean for an iTemp to be volatile, anyway? Passing
2046 TRUE is more cautious but may prevent possible optimizations */
2048 /* if the symbol is in far space then we should not */
2049 /* if (isOperandInFarSpace (IC_RIGHT (dic)))
2052 /* for + & - operations make sure that
2053 if it is on the stack it is the same
2054 as one of the three operands */
2056 if ((ic->op == '+' || ic->op == '-') &&
2057 OP_SYMBOL (IC_RIGHT (dic))->onStack)
2060 if (IC_RESULT (ic)->key != IC_RIGHT (dic)->key &&
2061 IC_LEFT (ic)->key != IC_RIGHT (dic)->key &&
2062 IC_RIGHT (ic)->key != IC_RIGHT (dic)->key)
2067 /* now make sure that the right side of dic
2068 is not defined between ic & dic */
2071 iCode *sic = dic->next;
2073 for (; sic != ic; sic = sic->next)
2074 if (IC_RESULT (sic) &&
2075 IC_RESULT (sic)->key == IC_RIGHT (dic)->key)
2082 /*-----------------------------------------------------------------*/
2083 /* reassignAliasedSym - used by packRegsForSupport to replace */
2084 /* redundant iTemp with equivalent symbol */
2085 /*-----------------------------------------------------------------*/
2087 reassignAliasedSym (eBBlock *ebp, iCode *assignment, iCode *use, operand *op)
2090 unsigned oldSymKey, newSymKey;
2092 oldSymKey = op->key;
2093 newSymKey = IC_RIGHT(assignment)->key;
2095 /* only track live ranges of compiler-generated temporaries */
2096 if (!IS_ITEMP(IC_RIGHT(assignment)))
2099 /* update the live-value bitmaps */
2100 for (ic = assignment; ic != use; ic = ic->next) {
2101 bitVectUnSetBit (ic->rlive, oldSymKey);
2103 ic->rlive = bitVectSetBit (ic->rlive, newSymKey);
2106 /* update the sym of the used operand */
2107 OP_SYMBOL(op) = OP_SYMBOL(IC_RIGHT(assignment));
2108 op->key = OP_SYMBOL(op)->key;
2110 /* update the sym's liverange */
2111 if ( OP_LIVETO(op) < ic->seq )
2112 setToRange(op, ic->seq, FALSE);
2114 /* remove the assignment iCode now that its result is unused */
2115 remiCodeFromeBBlock (ebp, assignment);
2116 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(assignment))->defs, assignment->key);
2117 hTabDeleteItem (&iCodehTab, assignment->key, assignment, DELETE_ITEM, NULL);
2121 /*-----------------------------------------------------------------*/
2122 /* packRegsForSupport :- reduce some registers for support calls */
2123 /*-----------------------------------------------------------------*/
2125 packRegsForSupport (iCode * ic, eBBlock * ebp)
2130 /* for the left & right operand :- look to see if the
2131 left was assigned a true symbol in far space in that
2132 case replace them */
2134 if (IS_ITEMP (IC_LEFT (ic)) &&
2135 OP_SYMBOL (IC_LEFT (ic))->liveTo <= ic->seq)
2137 dic = findAssignToSym (IC_LEFT (ic), ic);
2141 /* found it we need to remove it from the block */
2142 reassignAliasedSym (ebp, dic, ic, IC_LEFT(ic));
2147 /* do the same for the right operand */
2148 if (IS_ITEMP (IC_RIGHT (ic)) &&
2149 OP_SYMBOL (IC_RIGHT (ic))->liveTo <= ic->seq)
2151 iCode *dic = findAssignToSym (IC_RIGHT (ic), ic);
2155 /* found it we need to remove it from the block */
2156 reassignAliasedSym (ebp, dic, ic, IC_RIGHT(ic));
2164 #define IS_OP_RUONLY(x) (x && IS_SYMOP(x) && OP_SYMBOL(x)->ruonly)
2168 /*-----------------------------------------------------------------*/
2169 /* packRegsForOneuse : - will reduce some registers for single Use */
2170 /*-----------------------------------------------------------------*/
2172 packRegsForOneuse (iCode * ic, operand * op, eBBlock * ebp)
2177 /* if returning a literal then do nothing */
2181 /* only up to 2 bytes */
2182 if (getSize (operandType (op)) > (fReturnSizeHC08 - 2))
2187 if (ic->op != SEND //RETURN
2189 && !POINTER_SET (ic)
2190 && !POINTER_GET (ic) )
2193 if (ic->op == SEND && ic->argreg != 1) return NULL;
2195 /* this routine will mark the a symbol as used in one
2196 instruction use only && if the defintion is local
2197 (ie. within the basic block) && has only one definition &&
2198 that definiion is either a return value from a
2199 function or does not contain any variables in
2201 uses = bitVectCopy (OP_USES (op));
2202 bitVectUnSetBit (uses, ic->key); /* take away this iCode */
2203 if (!bitVectIsZero (uses)) /* has other uses */
2206 /* if it has only one defintion */
2207 if (bitVectnBitsOn (OP_DEFS (op)) > 1)
2208 return NULL; /* has more than one definition */
2210 /* get that definition */
2212 hTabItemWithKey (iCodehTab,
2213 bitVectFirstBit (OP_DEFS (op)))))
2216 /* if that only usage is a cast */
2217 if (dic->op == CAST) {
2218 /* to a bigger type */
2219 if (getSize(OP_SYM_TYPE(IC_RESULT(dic))) >
2220 getSize(OP_SYM_TYPE(IC_RIGHT(dic)))) {
2221 /* than we can not, since we cannot predict the usage of b & acc */
2226 /* found the definition now check if it is local */
2227 if (dic->seq < ebp->fSeq ||
2228 dic->seq > ebp->lSeq)
2229 return NULL; /* non-local */
2231 /* now check if it is the return from
2233 if (dic->op == CALL || dic->op == PCALL)
2235 if (ic->op != SEND && ic->op != RETURN &&
2236 !POINTER_SET(ic) && !POINTER_GET(ic))
2238 OP_SYMBOL (op)->ruonly = 1;
2245 /* otherwise check that the definition does
2246 not contain any symbols in far space */
2247 // if (isOperandInFarSpace (IC_LEFT (dic)) ||
2248 // isOperandInFarSpace (IC_RIGHT (dic)) ||
2249 // IS_OP_RUONLY (IC_LEFT (ic)) ||
2250 // IS_OP_RUONLY (IC_RIGHT (ic)))
2255 /* if pointer set then make sure the pointer
2258 if (POINTER_SET (dic) &&
2259 !IS_DATA_PTR (aggrToPtr (operandType (IC_RESULT (dic)), FALSE)))
2262 if (POINTER_GET (dic) &&
2263 !IS_DATA_PTR (aggrToPtr (operandType (IC_LEFT (dic)), FALSE)))
2269 /* also make sure the intervenening instructions
2270 don't have any thing in far space */
2271 for (dic = dic->next; dic && dic != ic && sic != ic; dic = dic->next)
2274 /* if there is an intervening function call then no */
2275 if (dic->op == CALL || dic->op == PCALL)
2277 /* if pointer set then make sure the pointer
2280 if (POINTER_SET (dic) &&
2281 !IS_DATA_PTR (aggrToPtr (operandType (IC_RESULT (dic)), FALSE)))
2284 if (POINTER_GET (dic) &&
2285 !IS_DATA_PTR (aggrToPtr (operandType (IC_LEFT (dic)), FALSE)))
2288 /* if address of & the result is remat the okay */
2289 if (dic->op == ADDRESS_OF &&
2290 OP_SYMBOL (IC_RESULT (dic))->remat)
2293 /* if operand has size of three or more & this
2294 operation is a '*','/' or '%' then 'b' may
2297 if ((dic->op == '%' || dic->op == '/' || dic->op == '*') &&
2298 getSize (operandType (op)) >= 3)
2302 /* if left or right or result is in far space */
2303 // if (isOperandInFarSpace (IC_LEFT (dic)) ||
2304 // isOperandInFarSpace (IC_RIGHT (dic)) ||
2305 // isOperandInFarSpace (IC_RESULT (dic)) ||
2306 // IS_OP_RUONLY (IC_LEFT (dic)) ||
2307 // IS_OP_RUONLY (IC_RIGHT (dic)) ||
2308 // IS_OP_RUONLY (IC_RESULT (dic)))
2312 // /* if left or right or result is on stack */
2313 // if (isOperandOnStack(IC_LEFT(dic)) ||
2314 // isOperandOnStack(IC_RIGHT(dic)) ||
2315 // isOperandOnStack(IC_RESULT(dic))) {
2320 OP_SYMBOL (op)->ruonly = 1;
2325 /*-----------------------------------------------------------------*/
2326 /* isBitwiseOptimizable - requirements of JEAN LOUIS VERN */
2327 /*-----------------------------------------------------------------*/
2329 isBitwiseOptimizable (iCode * ic)
2331 sym_link *ltype = getSpec (operandType (IC_LEFT (ic)));
2332 sym_link *rtype = getSpec (operandType (IC_RIGHT (ic)));
2334 /* bitwise operations are considered optimizable
2335 under the following conditions (Jean-Louis VERN)
2347 if (IS_LITERAL(rtype) ||
2348 (IS_BITVAR (ltype) && IN_BITSPACE (SPEC_OCLS (ltype))))
2354 /*-----------------------------------------------------------------*/
2355 /* isCommutativeOp - tests whether this op cares what order its */
2356 /* operands are in */
2357 /*-----------------------------------------------------------------*/
2358 bool isCommutativeOp2(unsigned int op)
2360 if (op == '+' || op == '*' || op == EQ_OP ||
2361 op == '^' || op == '|' || op == BITWISEAND)
2367 /*-----------------------------------------------------------------*/
2368 /* operandUsesAcc2 - determines whether the code generated for this */
2369 /* operand will have to use the accumulator */
2370 /*-----------------------------------------------------------------*/
2371 bool operandUsesAcc2(operand *op)
2377 symbol *sym = OP_SYMBOL(op);
2381 return TRUE; /* duh! */
2383 // if (IN_STACK(sym->etype) || sym->onStack ||
2384 // (SPIL_LOC(op) && SPIL_LOC(op)->onStack))
2385 // return TRUE; /* acc is used to calc stack offset */
2390 sym = SPIL_LOC(op); /* if spilled, look at spill location */
2392 return FALSE; /* more checks? */
2396 symspace = SPEC_OCLS(sym->etype);
2398 // if (sym->iaccess && symspace->paged)
2399 // return TRUE; /* must fetch paged indirect sym via accumulator */
2401 if (IN_BITSPACE(symspace))
2402 return TRUE; /* fetching bit vars uses the accumulator */
2404 if (IN_FARSPACE(symspace) || IN_CODESPACE(symspace))
2405 return TRUE; /* fetched via accumulator and dptr */
2411 /*-----------------------------------------------------------------*/
2412 /* packRegsForAccUse - pack registers for acc use */
2413 /*-----------------------------------------------------------------*/
2415 packRegsForAccUse (iCode * ic)
2419 /* if this is an aggregate, e.g. a one byte char array */
2420 if (IS_AGGREGATE(operandType(IC_RESULT(ic)))) {
2424 /* if we are calling a reentrant function that has stack parameters */
2426 if (ic->op == CALL &&
2427 IFFUNC_ISREENT(operandType(IC_LEFT(ic))) &&
2428 FUNC_HASSTACKPARM(operandType(IC_LEFT(ic))))
2431 if (ic->op == PCALL &&
2432 IFFUNC_ISREENT(operandType(IC_LEFT(ic))->next) &&
2433 FUNC_HASSTACKPARM(operandType(IC_LEFT(ic))->next))
2437 /* if + or - then it has to be one byte result */
2438 if ((ic->op == '+' || ic->op == '-')
2439 && getSize (operandType (IC_RESULT (ic))) > 1)
2443 /* if shift operation make sure right side is a literal */
2444 if (ic->op == RIGHT_OP &&
2445 (!isOperandLiteral (IC_RIGHT (ic)) ||
2446 (getSize (operandType (IC_RESULT (ic) )) > 1)))
2449 if (ic->op == LEFT_OP &&
2450 (!isOperandLiteral (IC_RIGHT (ic)) ||
2451 (getSize (operandType (IC_RESULT (ic) )) > 1)))
2454 if (IS_BITWISE_OP (ic) &&
2455 getSize (operandType (IC_RESULT (ic))) > 1)
2459 /* has only one definition */
2460 if (bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) > 1)
2463 /* has only one use */
2464 if (bitVectnBitsOn (OP_USES (IC_RESULT (ic))) > 1)
2467 /* and the usage immediately follows this iCode */
2468 if (!(uic = hTabItemWithKey (iCodehTab,
2469 bitVectFirstBit (OP_USES (IC_RESULT (ic))))))
2472 if (ic->next != uic)
2475 /* if it is a conditional branch then we definitely can */
2479 if (uic->op == JUMPTABLE)
2483 if (POINTER_SET (uic) &&
2484 getSize (aggrToPtr (operandType (IC_RESULT (uic)), FALSE)) > 1)
2488 /* if the usage is not is an assignment
2489 or an arithmetic / bitwise / shift operation then not */
2490 if (uic->op != '=' &&
2491 !IS_ARITHMETIC_OP (uic) &&
2492 !IS_BITWISE_OP (uic) &&
2493 (uic->op != LEFT_OP) &&
2494 (uic->op != RIGHT_OP) &&
2495 (uic->op != GETHBIT) &&
2496 (uic->op != RETURN) &&
2502 /* if used in ^ operation then make sure right is not a
2503 literal (WIML: Why is this?) */
2504 if (uic->op == '^' && isOperandLiteral (IC_RIGHT (uic)))
2507 /* if shift operation make sure right side is not a literal */
2508 /* WIML: Why is this? */
2509 if (uic->op == RIGHT_OP &&
2510 (isOperandLiteral (IC_RIGHT (uic)) ||
2511 getSize (operandType (IC_RESULT (uic))) > 1))
2513 if (uic->op == LEFT_OP &&
2514 (isOperandLiteral (IC_RIGHT (uic)) ||
2515 getSize (operandType (IC_RESULT (uic))) > 1))
2519 /* make sure that the result of this icode is not on the
2520 stack, since acc is used to compute stack offset */
2522 if (IS_TRUE_SYMOP (IC_RESULT (uic)) &&
2523 OP_SYMBOL (IC_RESULT (uic))->onStack)
2526 // if (isOperandOnStack(IC_RESULT(uic)))
2530 /* if the usage has only one operand then we can */
2531 if (IC_LEFT (uic) == NULL ||
2532 IC_RIGHT (uic) == NULL)
2536 /* if the other operand uses the accumulator then we cannot */
2537 if ( (IC_LEFT(uic)->key == IC_RESULT(ic)->key &&
2538 operandUsesAcc2(IC_RIGHT(uic))) ||
2539 (IC_RIGHT(uic)->key == IC_RESULT(ic)->key &&
2540 operandUsesAcc2(IC_LEFT(uic))) )
2543 /* make sure this is on the left side if not commutative */
2544 /* except for '-', which has been written to be able to
2545 handle reversed operands */
2546 if (!(isCommutativeOp2(ic->op) || ic->op == '-') &&
2547 IC_LEFT (uic)->key != IC_RESULT (ic)->key)
2552 // this is too dangerous and need further restrictions
2555 /* if one of them is a literal then we can */
2556 if ((IC_LEFT (uic) && IS_OP_LITERAL (IC_LEFT (uic))) ||
2557 (IC_RIGHT (uic) && IS_OP_LITERAL (IC_RIGHT (uic))))
2559 OP_SYMBOL (IC_RESULT (ic))->accuse = 1;
2566 if ((POINTER_GET(uic))
2567 || (ic->op == ADDRESS_OF && uic->op == '+' && IS_OP_LITERAL (IC_RIGHT (uic))))
2569 OP_SYMBOL (IC_RESULT (ic))->accuse = ACCUSE_HX;
2573 OP_SYMBOL (IC_RESULT (ic))->accuse = ACCUSE_XA;
2576 /*-----------------------------------------------------------------*/
2577 /* packForPush - hueristics to reduce iCode for pushing */
2578 /*-----------------------------------------------------------------*/
2580 packForPush (iCode * ic, eBBlock ** ebpp, int blockno)
2584 struct eBBlock * ebp=ebpp[blockno];
2586 if (ic->op != IPUSH || !IS_ITEMP (IC_LEFT (ic)))
2589 /* must have only definition & one usage */
2590 if (bitVectnBitsOn (OP_DEFS (IC_LEFT (ic))) != 1 ||
2591 bitVectnBitsOn (OP_USES (IC_LEFT (ic))) != 1)
2594 /* find the definition */
2595 if (!(dic = hTabItemWithKey (iCodehTab,
2596 bitVectFirstBit (OP_DEFS (IC_LEFT (ic))))))
2599 if (dic->op != '=' || POINTER_SET (dic))
2602 if (dic->seq < ebp->fSeq) { // Evelyn did this
2604 for (i=0; i<blockno; i++) {
2605 if (dic->seq >= ebpp[i]->fSeq && dic->seq <= ebpp[i]->lSeq) {
2610 wassert (i!=blockno); // no way to recover from here
2613 if (IS_SYMOP(IC_RIGHT(dic))) {
2614 /* make sure the right side does not have any definitions
2616 dbv = OP_DEFS(IC_RIGHT(dic));
2617 for (lic = ic; lic && lic != dic ; lic = lic->prev) {
2618 if (bitVectBitValue(dbv,lic->key))
2621 /* make sure they have the same type */
2622 if (IS_SPEC(operandType(IC_LEFT(ic))))
2624 sym_link *itype=operandType(IC_LEFT(ic));
2625 sym_link *ditype=operandType(IC_RIGHT(dic));
2627 if (SPEC_USIGN(itype)!=SPEC_USIGN(ditype) ||
2628 SPEC_LONG(itype)!=SPEC_LONG(ditype))
2631 /* extend the live range of replaced operand if needed */
2632 if (OP_SYMBOL(IC_RIGHT(dic))->liveTo < ic->seq) {
2633 OP_SYMBOL(IC_RIGHT(dic))->liveTo = ic->seq;
2635 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2638 /* we now we know that it has one & only one def & use
2639 and the that the definition is an assignment */
2640 ReplaceOpWithCheaperOp(&IC_LEFT (ic), IC_RIGHT (dic));
2641 remiCodeFromeBBlock (ebp, dic);
2642 hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
2645 /*-----------------------------------------------------------------*/
2646 /* packRegisters - does some transformations to reduce register */
2648 /*-----------------------------------------------------------------*/
2650 packRegisters (eBBlock ** ebpp, int blockno)
2654 eBBlock *ebp=ebpp[blockno];
2661 /* look for assignments of the form */
2662 /* iTempNN = TRueSym (someoperation) SomeOperand */
2664 /* TrueSym := iTempNN:1 */
2665 for (ic = ebp->sch; ic; ic = ic->next)
2667 /* find assignment of the form TrueSym := iTempNN:1 */
2668 if (ic->op == '=' && !POINTER_SET (ic) )
2669 change += packRegsForAssign (ic, ebp);
2676 for (ic = ebp->sch; ic; ic = ic->next)
2678 /* if this is an itemp & result of an address of a true sym
2679 then mark this as rematerialisable */
2680 if (ic->op == ADDRESS_OF &&
2681 IS_ITEMP (IC_RESULT (ic)) &&
2682 IS_TRUE_SYMOP (IC_LEFT (ic)) &&
2683 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1 &&
2684 !OP_SYMBOL (IC_LEFT (ic))->onStack )
2687 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2688 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2689 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2693 /* if straight assignment then carry remat flag if
2694 this is the only definition */
2695 if (ic->op == '=' &&
2696 !POINTER_SET (ic) &&
2697 IS_SYMOP (IC_RIGHT (ic)) &&
2698 OP_SYMBOL (IC_RIGHT (ic))->remat &&
2699 !IS_CAST_ICODE(OP_SYMBOL (IC_RIGHT (ic))->rematiCode) &&
2700 bitVectnBitsOn (OP_SYMBOL (IC_RESULT (ic))->defs) <= 1)
2703 OP_SYMBOL (IC_RESULT (ic))->remat =
2704 OP_SYMBOL (IC_RIGHT (ic))->remat;
2705 OP_SYMBOL (IC_RESULT (ic))->rematiCode =
2706 OP_SYMBOL (IC_RIGHT (ic))->rematiCode;
2709 /* if cast to a generic pointer & the pointer being
2710 cast is remat, then we can remat this cast as well */
2711 if (ic->op == CAST &&
2712 IS_SYMOP(IC_RIGHT(ic)) &&
2713 OP_SYMBOL(IC_RIGHT(ic))->remat &&
2714 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1) {
2715 sym_link *to_type = operandType(IC_LEFT(ic));
2716 sym_link *from_type = operandType(IC_RIGHT(ic));
2717 if (IS_GENPTR(to_type) && IS_PTR(from_type)) {
2718 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2719 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2720 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2724 /* if this is a +/- operation with a rematerizable
2725 then mark this as rematerializable as well */
2726 if ((ic->op == '+' || ic->op == '-') &&
2727 (IS_SYMOP (IC_LEFT (ic)) &&
2728 IS_ITEMP (IC_RESULT (ic)) &&
2729 IS_OP_LITERAL (IC_RIGHT (ic))) &&
2730 OP_SYMBOL (IC_LEFT (ic))->remat &&
2731 (!IS_SYMOP (IC_RIGHT (ic)) || !IS_CAST_ICODE(OP_SYMBOL (IC_RIGHT (ic))->rematiCode)) &&
2732 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1)
2734 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2735 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2736 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2739 /* mark the pointer usages */
2740 if (POINTER_SET (ic))
2741 OP_SYMBOL (IC_RESULT (ic))->uptr = 1;
2743 if (POINTER_GET (ic) &&
2744 IS_SYMOP(IC_LEFT (ic)))
2745 OP_SYMBOL (IC_LEFT (ic))->uptr = 1;
2750 /* if we are using a symbol on the stack
2751 then we should say hc08_ptrRegReq */
2752 if (ic->op == IFX && IS_SYMOP (IC_COND (ic)))
2753 hc08_ptrRegReq += ((OP_SYMBOL (IC_COND (ic))->onStack ||
2754 OP_SYMBOL (IC_COND (ic))->iaccess) ? 1 : 0);
2755 else if (ic->op == JUMPTABLE && IS_SYMOP (IC_JTCOND (ic)))
2756 hc08_ptrRegReq += ((OP_SYMBOL (IC_JTCOND (ic))->onStack ||
2757 OP_SYMBOL (IC_JTCOND (ic))->iaccess) ? 1 : 0);
2760 if (IS_SYMOP (IC_LEFT (ic)))
2761 hc08_ptrRegReq += ((OP_SYMBOL (IC_LEFT (ic))->onStack ||
2762 OP_SYMBOL (IC_LEFT (ic))->iaccess) ? 1 : 0);
2763 if (IS_SYMOP (IC_RIGHT (ic)))
2764 hc08_ptrRegReq += ((OP_SYMBOL (IC_RIGHT (ic))->onStack ||
2765 OP_SYMBOL (IC_RIGHT (ic))->iaccess) ? 1 : 0);
2766 if (IS_SYMOP (IC_RESULT (ic)))
2767 hc08_ptrRegReq += ((OP_SYMBOL (IC_RESULT (ic))->onStack ||
2768 OP_SYMBOL (IC_RESULT (ic))->iaccess) ? 1 : 0);
2773 /* if the condition of an if instruction
2774 is defined in the previous instruction and
2775 this is the only usage then
2776 mark the itemp as a conditional */
2777 if ((IS_CONDITIONAL (ic) ||
2778 (IS_BITWISE_OP(ic) && isBitwiseOptimizable (ic))) &&
2779 ic->next && ic->next->op == IFX &&
2780 bitVectnBitsOn (OP_USES(IC_RESULT(ic)))==1 &&
2781 isOperandEqual (IC_RESULT (ic), IC_COND (ic->next)) &&
2782 OP_SYMBOL (IC_RESULT (ic))->liveTo <= ic->next->seq)
2784 OP_SYMBOL (IC_RESULT (ic))->regType = REG_CND;
2788 /* reduce for support function calls */
2789 if (ic->supportRtn || (ic->op != IFX && ic->op != JUMPTABLE))
2790 packRegsForSupport (ic, ebp);
2793 /* some cases the redundant moves can
2794 can be eliminated for return statements */
2795 if ((ic->op == RETURN || (ic->op == SEND && ic->argreg == 1)) &&
2796 /* !isOperandInFarSpace (IC_LEFT (ic)) && */
2797 options.model == MODEL_SMALL) {
2798 packRegsForOneuse (ic, IC_LEFT (ic), ebp);
2801 /* if pointer set & left has a size more than
2802 one and right is not in far space */
2803 if (POINTER_SET (ic) &&
2804 /* !isOperandInFarSpace (IC_RIGHT (ic)) && */
2805 !OP_SYMBOL (IC_RESULT (ic))->remat &&
2806 !IS_OP_RUONLY (IC_RIGHT (ic))
2807 /* && getSize (aggrToPtr (operandType (IC_RESULT (ic)), FALSE)) > 1 */ )
2808 packRegsForOneuse (ic, IC_RESULT (ic), ebp);
2810 /* if pointer get */
2811 if (POINTER_GET (ic) &&
2812 IS_SYMOP (IC_LEFT (ic)) &&
2813 /* !isOperandInFarSpace (IC_RESULT (ic)) && */
2814 !OP_SYMBOL (IC_LEFT (ic))->remat &&
2815 !IS_OP_RUONLY (IC_RESULT (ic))
2816 /* && getSize (aggrToPtr (operandType (IC_LEFT (ic)), FALSE)) > 1 */)
2817 packRegsForOneuse (ic, IC_LEFT (ic), ebp);
2820 /* if this is cast for intergral promotion then
2821 check if only use of the definition of the
2822 operand being casted/ if yes then replace
2823 the result of that arithmetic operation with
2824 this result and get rid of the cast */
2827 sym_link *fromType = operandType (IC_RIGHT (ic));
2828 sym_link *toType = operandType (IC_LEFT (ic));
2830 if (IS_INTEGRAL (fromType) && IS_INTEGRAL (toType) &&
2831 getSize (fromType) != getSize (toType) &&
2832 SPEC_USIGN (fromType) == SPEC_USIGN (toType))
2835 iCode *dic = packRegsForOneuse (ic, IC_RIGHT (ic), ebp);
2838 if (IS_ARITHMETIC_OP (dic))
2840 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2841 ReplaceOpWithCheaperOp(&IC_RESULT (dic), IC_RESULT (ic));
2842 remiCodeFromeBBlock (ebp, ic);
2843 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
2844 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
2845 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
2849 OP_SYMBOL (IC_RIGHT (ic))->ruonly = 0;
2855 /* if the type from and type to are the same
2856 then if this is the only use then packit */
2857 if (compareType (operandType (IC_RIGHT (ic)),
2858 operandType (IC_LEFT (ic))) == 1)
2860 iCode *dic = packRegsForOneuse (ic, IC_RIGHT (ic), ebp);
2863 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2864 ReplaceOpWithCheaperOp(&IC_RESULT (dic), IC_RESULT (ic));
2865 remiCodeFromeBBlock (ebp, ic);
2866 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
2867 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
2868 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
2877 iTempNN := (some variable in farspace) V1
2882 if (ic->op == IPUSH)
2884 packForPush (ic, ebpp, blockno);
2889 /* pack registers for accumulator use, when the
2890 result of an arithmetic or bit wise operation
2891 has only one use, that use is immediately following
2892 the defintion and the using iCode has only one
2893 operand or has two operands but one is literal &
2894 the result of that operation is not on stack then
2895 we can leave the result of this operation in x:a
2897 if ((IS_ARITHMETIC_OP (ic)
2898 || IS_CONDITIONAL(ic)
2899 || IS_BITWISE_OP (ic)
2903 || ic->op == GETHBIT
2904 || ic->op == LEFT_OP || ic->op == RIGHT_OP || ic->op == CALL
2905 || (ic->op == ADDRESS_OF && isOperandOnStack (IC_LEFT (ic)))
2907 IS_ITEMP (IC_RESULT (ic)) &&
2908 getSize (operandType (IC_RESULT (ic))) <= 1)
2910 packRegsForAccUse (ic);
2915 /*-----------------------------------------------------------------*/
2916 /* assignRegisters - assigns registers to each live range as need */
2917 /*-----------------------------------------------------------------*/
2919 hc08_assignRegisters (eBBlock ** ebbs, int count)
2924 setToNull ((void *) &_G.funcrUsed);
2925 setToNull ((void *) &_G.regAssigned);
2926 setToNull ((void *) &_G.totRegAssigned);
2927 hc08_ptrRegReq = _G.stackExtend = _G.dataExtend = 0;
2929 hc08_reg_a = hc08_regWithIdx(A_IDX);
2930 hc08_reg_x = hc08_regWithIdx(X_IDX);
2931 hc08_reg_h = hc08_regWithIdx(H_IDX);
2932 hc08_reg_hx = hc08_regWithIdx(HX_IDX);
2933 hc08_reg_xa = hc08_regWithIdx(XA_IDX);
2935 /* change assignments this will remove some
2936 live ranges reducing some register pressure */
2937 for (i = 0; i < count; i++)
2938 packRegisters (ebbs, i);
2940 if (options.dump_pack)
2941 dumpEbbsToFileExt (DUMP_PACK, ebbs, count);
2943 /* first determine for each live range the number of
2944 registers & the type of registers required for each */
2947 /* and serially allocate registers */
2948 serialRegAssign (ebbs, count);
2951 //setToNull ((void *) &_G.regAssigned);
2952 //setToNull ((void *) &_G.totRegAssigned);
2955 /* if stack was extended then tell the user */
2958 /* werror(W_TOOMANY_SPILS,"stack", */
2959 /* _G.stackExtend,currFunc->name,""); */
2965 /* werror(W_TOOMANY_SPILS,"data space", */
2966 /* _G.dataExtend,currFunc->name,""); */
2970 /* after that create the register mask
2971 for each of the instruction */
2972 createRegMask (ebbs, count);
2974 /* redo that offsets for stacked automatic variables */
2976 redoStackOffsets ();
2979 if (options.dump_rassgn)
2981 dumpEbbsToFileExt (DUMP_RASSGN, ebbs, count);
2982 dumpLiveRanges (DUMP_LRANGE, liveRanges);
2985 /* do the overlaysegment stuff SDCCmem.c */
2986 doOverlays (ebbs, count);
2988 /* now get back the chain */
2989 ic = iCodeLabelOptimize (iCodeFromeBBlock (ebbs, count));
2993 /* free up any _G.stackSpil locations allocated */
2994 applyToSet (_G.stackSpil, deallocStackSpil);
2996 setToNull ((void **) &_G.stackSpil);
2997 setToNull ((void **) &_G.spiltSet);
2998 /* mark all registers as free */