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, "a", 1, NULL, 0, 1},
65 {REG_GPR, X_IDX, "x", 2, NULL, 0, 1},
66 {REG_GPR, H_IDX, "h", 4, NULL, 0, 1},
67 {REG_PTR, HX_IDX, "hx", 6, NULL, 0, 1},
68 {REG_GPR, XA_IDX, "xa", 3, NULL, 0, 1},
70 {REG_CND, CND_IDX, "C", 0, NULL, 0, 1},
71 {0, SP_IDX, "sp", 0, NULL, 0, 1},
82 static void spillThis (symbol *);
83 static void freeAllRegs ();
85 /*-----------------------------------------------------------------*/
86 /* allocReg - allocates register of given type */
87 /*-----------------------------------------------------------------*/
93 if ((type==REG_PTR) && (regshc08[HX_IDX].isFree))
95 regshc08[HX_IDX].isFree = 0;
98 bitVectSetBit (currFunc->regsUsed, HX_IDX);
99 return ®shc08[HX_IDX];
104 /*-----------------------------------------------------------------*/
105 /* hc08_regWithIdx - returns pointer to register wit index number */
106 /*-----------------------------------------------------------------*/
108 hc08_regWithIdx (int idx)
112 for (i = 0; i < hc08_nRegs; i++)
113 if (regshc08[i].rIdx == idx)
116 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
117 "regWithIdx not found");
121 /*-----------------------------------------------------------------*/
122 /* hc08_freeReg - frees a register */
123 /*-----------------------------------------------------------------*/
125 hc08_freeReg (regs * reg)
129 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
130 "hc08_freeReg - Freeing NULL register");
139 if (hc08_reg_x->isFree)
140 hc08_reg_xa->isFree = 1;
143 if (hc08_reg_a->isFree)
144 hc08_reg_xa->isFree = 1;
145 if (hc08_reg_h->isFree)
146 hc08_reg_hx->isFree = 1;
149 if (hc08_reg_x->isFree)
150 hc08_reg_hx->isFree = 1;
153 hc08_reg_h->isFree = 1;
154 hc08_reg_x->isFree = 1;
155 if (hc08_reg_a->isFree)
156 hc08_reg_xa->isFree = 1;
159 hc08_reg_x->isFree = 1;
160 hc08_reg_a->isFree = 1;
161 if (hc08_reg_h->isFree)
162 hc08_reg_hx->isFree = 1;
170 /*-----------------------------------------------------------------*/
171 /* nFreeRegs - returns number of free registers */
172 /*-----------------------------------------------------------------*/
181 for (i = 0; i < hc08_nRegs; i++)
182 if (regshc08[i].isFree && regshc08[i].type == type)
187 /*-----------------------------------------------------------------*/
188 /* nfreeRegsType - free registers with type */
189 /*-----------------------------------------------------------------*/
191 nfreeRegsType (int type)
196 if ((nfr = nFreeRegs (type)) == 0)
197 return nFreeRegs (REG_GPR);
200 return nFreeRegs (type);
203 /*-----------------------------------------------------------------*/
204 /* hc08_useReg - marks a register as used */
205 /*-----------------------------------------------------------------*/
207 hc08_useReg (regs * reg)
214 hc08_reg_xa->aop = NULL;
215 hc08_reg_xa->isFree = 0;
218 hc08_reg_xa->aop = NULL;
219 hc08_reg_xa->isFree = 0;
220 hc08_reg_hx->aop = NULL;
221 hc08_reg_hx->isFree = 0;
224 hc08_reg_hx->aop = NULL;
225 hc08_reg_hx->isFree = 0;
228 hc08_reg_h->aop = NULL;
229 hc08_reg_h->isFree = 0;
230 hc08_reg_x->aop = NULL;
231 hc08_reg_x->isFree = 0;
234 hc08_reg_x->aop = NULL;
235 hc08_reg_x->isFree = 0;
236 hc08_reg_a->aop = NULL;
237 hc08_reg_a->isFree = 0;
245 /*-----------------------------------------------------------------*/
246 /* hc08_dirtyReg - marks a register as dirty */
247 /*-----------------------------------------------------------------*/
249 hc08_dirtyReg (regs * reg, bool freereg)
256 hc08_reg_xa->aop = NULL;
259 hc08_reg_xa->aop = NULL;
260 hc08_reg_hx->aop = NULL;
263 hc08_reg_hx->aop = NULL;
266 hc08_reg_h->aop = NULL;
267 hc08_reg_x->aop = NULL;
270 hc08_reg_x->aop = NULL;
271 hc08_reg_a->aop = NULL;
280 /*-----------------------------------------------------------------*/
281 /* computeSpillable - given a point find the spillable live ranges */
282 /*-----------------------------------------------------------------*/
284 computeSpillable (iCode * ic)
288 /* spillable live ranges are those that are live at this
289 point . the following categories need to be subtracted
291 a) - those that are already spilt
292 b) - if being used by this one
293 c) - defined by this one */
295 spillable = bitVectCopy (ic->rlive);
297 bitVectCplAnd (spillable, _G.spiltSet); /* those already spilt */
299 bitVectCplAnd (spillable, ic->uses); /* used in this one */
300 bitVectUnSetBit (spillable, ic->defKey);
301 spillable = bitVectIntersect (spillable, _G.regAssigned);
306 /*-----------------------------------------------------------------*/
307 /* noSpilLoc - return true if a variable has no spil location */
308 /*-----------------------------------------------------------------*/
310 noSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
312 return (sym->usl.spillLoc ? 0 : 1);
315 /*-----------------------------------------------------------------*/
316 /* hasSpilLoc - will return 1 if the symbol has spil location */
317 /*-----------------------------------------------------------------*/
319 hasSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
321 return (sym->usl.spillLoc ? 1 : 0);
324 /*-----------------------------------------------------------------*/
325 /* directSpilLoc - will return 1 if the splilocation is in direct */
326 /*-----------------------------------------------------------------*/
328 directSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
330 if (sym->usl.spillLoc &&
331 (IN_DIRSPACE (SPEC_OCLS (sym->usl.spillLoc->etype))))
337 /*-----------------------------------------------------------------*/
338 /* hasSpilLocnoUptr - will return 1 if the symbol has spil location */
339 /* but is not used as a pointer */
340 /*-----------------------------------------------------------------*/
342 hasSpilLocnoUptr (symbol * sym, eBBlock * ebp, iCode * ic)
344 return ((sym->usl.spillLoc && !sym->uptr) ? 1 : 0);
347 /*-----------------------------------------------------------------*/
348 /* rematable - will return 1 if the remat flag is set */
349 /*-----------------------------------------------------------------*/
351 rematable (symbol * sym, eBBlock * ebp, iCode * ic)
356 /*-----------------------------------------------------------------*/
357 /* notUsedInRemaining - not used or defined in remain of the block */
358 /*-----------------------------------------------------------------*/
360 notUsedInRemaining (symbol * sym, eBBlock * ebp, iCode * ic)
362 return ((usedInRemaining (operandFromSymbol (sym), ic) ? 0 : 1) &&
363 allDefsOutOfRange (sym->defs, ebp->fSeq, ebp->lSeq));
366 /*-----------------------------------------------------------------*/
367 /* allLRs - return true for all */
368 /*-----------------------------------------------------------------*/
370 allLRs (symbol * sym, eBBlock * ebp, iCode * ic)
375 /*-----------------------------------------------------------------*/
376 /* liveRangesWith - applies function to a given set of live range */
377 /*-----------------------------------------------------------------*/
379 liveRangesWith (bitVect * lrs, int (func) (symbol *, eBBlock *, iCode *),
380 eBBlock * ebp, iCode * ic)
385 if (!lrs || !lrs->size)
388 for (i = 1; i < lrs->size; i++)
391 if (!bitVectBitValue (lrs, i))
394 /* if we don't find it in the live range
395 hash table we are in serious trouble */
396 if (!(sym = hTabItemWithKey (liveRanges, i)))
398 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
399 "liveRangesWith could not find liveRange");
403 if (func (sym, ebp, ic) && bitVectBitValue (_G.regAssigned, sym->key))
404 addSetHead (&rset, sym);
411 /*-----------------------------------------------------------------*/
412 /* leastUsedLR - given a set determines which is the least used */
413 /*-----------------------------------------------------------------*/
415 leastUsedLR (set * sset)
417 symbol *sym = NULL, *lsym = NULL;
419 sym = lsym = setFirstItem (sset);
424 for (; lsym; lsym = setNextItem (sset))
427 /* if usage is the same then prefer
428 the spill the smaller of the two */
429 if (lsym->used == sym->used)
430 if (getSize (lsym->type) < getSize (sym->type))
434 if (lsym->used < sym->used)
439 setToNull ((void *) &sset);
444 /*-----------------------------------------------------------------*/
445 /* noOverLap - will iterate through the list looking for over lap */
446 /*-----------------------------------------------------------------*/
448 noOverLap (set * itmpStack, symbol * fsym)
453 for (sym = setFirstItem (itmpStack); sym;
454 sym = setNextItem (itmpStack))
456 if (bitVectBitValue(sym->clashes,fsym->key)) return 0;
462 /*-----------------------------------------------------------------*/
463 /* isFree - will return 1 if the a free spil location is found */
464 /*-----------------------------------------------------------------*/
469 V_ARG (symbol **, sloc);
470 V_ARG (symbol *, fsym);
472 /* if already found */
476 /* if it is free && and the itmp assigned to
477 this does not have any overlapping live ranges
478 with the one currently being assigned and
479 the size can be accomodated */
481 noOverLap (sym->usl.itmpStack, fsym) &&
482 getSize (sym->type) >= getSize (fsym->type))
491 /*-----------------------------------------------------------------*/
492 /* spillLRWithPtrReg :- will spil those live ranges which use PTR */
493 /*-----------------------------------------------------------------*/
495 spillLRWithPtrReg (symbol * forSym)
501 if (!_G.regAssigned ||
502 bitVectIsZero (_G.regAssigned))
505 hx = hc08_regWithIdx (HX_IDX);
507 /* for all live ranges */
508 for (lrsym = hTabFirstItem (liveRanges, &k); lrsym;
509 lrsym = hTabNextItem (liveRanges, &k))
513 /* if no registers assigned to it or spilt */
514 /* if it does not overlap with this then
515 not need to spill it */
517 if (lrsym->isspilt || !lrsym->nRegs ||
518 (lrsym->liveTo < forSym->liveFrom))
521 /* go thru the registers : if it is either
522 r0 or r1 then spil it */
523 for (j = 0; j < lrsym->nRegs; j++)
524 if (lrsym->regs[j] == hx)
533 /*-----------------------------------------------------------------*/
534 /* createStackSpil - create a location on the stack to spil */
535 /*-----------------------------------------------------------------*/
537 createStackSpil (symbol * sym)
540 int useXstack, model;
544 /* first go try and find a free one that is already
545 existing on the stack */
546 if (applyToSet (_G.stackSpil, isFree, &sloc, sym))
548 /* found a free one : just update & return */
549 sym->usl.spillLoc = sloc;
552 addSetHead (&sloc->usl.itmpStack, sym);
556 /* could not then have to create one , this is the hard part
557 we need to allocate this on the stack : this is really a
558 hack!! but cannot think of anything better at this time */
560 if (sprintf (slocBuffer, "sloc%d", _G.slocNum++) >= sizeof (slocBuffer))
562 fprintf (stderr, "***Internal error: slocBuffer overflowed: %s:%d\n",
567 sloc = newiTemp (slocBuffer);
569 /* set the type to the spilling symbol */
570 sloc->type = copyLinkChain (sym->type);
571 sloc->etype = getSpec (sloc->type);
572 SPEC_SCLS (sloc->etype) = S_DATA;
573 SPEC_EXTR (sloc->etype) = 0;
574 SPEC_STAT (sloc->etype) = 0;
575 SPEC_VOLATILE(sloc->etype) = 0;
576 SPEC_ABSA(sloc->etype) = 0;
578 /* we don't allow it to be allocated`
579 onto the external stack since : so we
580 temporarily turn it off ; we also
581 turn off memory model to prevent
582 the spil from going to the external storage
585 useXstack = options.useXstack;
586 model = options.model;
587 /* noOverlay = options.noOverlay; */
588 /* options.noOverlay = 1; */
589 options.model = options.useXstack = 0;
593 options.useXstack = useXstack;
594 options.model = model;
595 /* options.noOverlay = noOverlay; */
596 sloc->isref = 1; /* to prevent compiler warning */
598 /* if it is on the stack then update the stack */
599 if (IN_STACK (sloc->etype))
601 currFunc->stack += getSize (sloc->type);
602 _G.stackExtend += getSize (sloc->type);
605 _G.dataExtend += getSize (sloc->type);
607 /* add it to the _G.stackSpil set */
608 addSetHead (&_G.stackSpil, sloc);
609 sym->usl.spillLoc = sloc;
612 /* add it to the set of itempStack set
613 of the spill location */
614 addSetHead (&sloc->usl.itmpStack, sym);
618 /*-----------------------------------------------------------------*/
619 /* isSpiltOnStack - returns true if the spil location is on stack */
620 /*-----------------------------------------------------------------*/
622 isSpiltOnStack (symbol * sym)
632 /* if (sym->_G.stackSpil) */
635 if (!sym->usl.spillLoc)
638 etype = getSpec (sym->usl.spillLoc->type);
639 if (IN_STACK (etype))
645 /*-----------------------------------------------------------------*/
646 /* spillThis - spils a specific operand */
647 /*-----------------------------------------------------------------*/
649 spillThis (symbol * sym)
652 /* if this is rematerializable or has a spillLocation
653 we are okay, else we need to create a spillLocation
655 if (!(sym->remat || sym->usl.spillLoc))
656 createStackSpil (sym);
658 /* mark it has spilt & put it in the spilt set */
659 sym->isspilt = sym->spillA = 1;
660 _G.spiltSet = bitVectSetBit (_G.spiltSet, sym->key);
662 bitVectUnSetBit (_G.regAssigned, sym->key);
663 bitVectUnSetBit (_G.totRegAssigned, sym->key);
665 for (i = 0; i < sym->nRegs; i++)
669 hc08_freeReg (sym->regs[i]);
673 /* if spilt on stack then free up r0 & r1
674 if they could have been assigned to some
676 // if (!hc08_ptrRegReq && isSpiltOnStack (sym))
679 // spillLRWithPtrReg (sym);
682 if (sym->usl.spillLoc && !sym->remat)
683 sym->usl.spillLoc->allocreq++;
687 /*-----------------------------------------------------------------*/
688 /* selectSpil - select a iTemp to spil : rather a simple procedure */
689 /*-----------------------------------------------------------------*/
691 selectSpil (iCode * ic, eBBlock * ebp, symbol * forSym)
693 bitVect *lrcs = NULL;
697 /* get the spillable live ranges */
698 lrcs = computeSpillable (ic);
700 /* get all live ranges that are rematerizable */
701 if ((selectS = liveRangesWith (lrcs, rematable, ebp, ic)))
704 /* return the least used of these */
705 return leastUsedLR (selectS);
708 /* get live ranges with spillLocations in direct space */
709 if ((selectS = liveRangesWith (lrcs, directSpilLoc, ebp, ic)))
711 sym = leastUsedLR (selectS);
712 strcpy (sym->rname, (sym->usl.spillLoc->rname[0] ?
713 sym->usl.spillLoc->rname :
714 sym->usl.spillLoc->name));
716 /* mark it as allocation required */
717 sym->usl.spillLoc->allocreq++;
721 /* if the symbol is local to the block then */
722 if (forSym->liveTo < ebp->lSeq)
725 /* check if there are any live ranges allocated
726 to registers that are not used in this block */
727 if (!_G.blockSpil && (selectS = liveRangesWith (lrcs, notUsedInBlock, ebp, ic)))
729 sym = leastUsedLR (selectS);
730 /* if this is not rematerializable */
739 /* check if there are any live ranges that not
740 used in the remainder of the block */
741 if (!_G.blockSpil && (selectS = liveRangesWith (lrcs, notUsedInRemaining, ebp, ic)))
743 sym = leastUsedLR (selectS);
756 /* find live ranges with spillocation && not used as pointers */
757 if ((selectS = liveRangesWith (lrcs, hasSpilLocnoUptr, ebp, ic)))
760 sym = leastUsedLR (selectS);
761 /* mark this as allocation required */
762 sym->usl.spillLoc->allocreq++;
766 /* find live ranges with spillocation */
767 if ((selectS = liveRangesWith (lrcs, hasSpilLoc, ebp, ic)))
770 sym = leastUsedLR (selectS);
771 sym->usl.spillLoc->allocreq++;
775 /* couldn't find then we need to create a spil
776 location on the stack , for which one? the least
778 if ((selectS = liveRangesWith (lrcs, noSpilLoc, ebp, ic)))
781 /* return a created spil location */
782 sym = createStackSpil (leastUsedLR (selectS));
783 sym->usl.spillLoc->allocreq++;
787 /* this is an extreme situation we will spill
788 this one : happens very rarely but it does happen */
794 /*-----------------------------------------------------------------*/
795 /* spilSomething - spil some variable & mark registers as free */
796 /*-----------------------------------------------------------------*/
798 spilSomething (iCode * ic, eBBlock * ebp, symbol * forSym)
803 /* get something we can spil */
804 ssym = selectSpil (ic, ebp, forSym);
806 /* mark it as spilt */
807 ssym->isspilt = ssym->spillA = 1;
808 _G.spiltSet = bitVectSetBit (_G.spiltSet, ssym->key);
810 /* mark it as not register assigned &
811 take it away from the set */
812 bitVectUnSetBit (_G.regAssigned, ssym->key);
813 bitVectUnSetBit (_G.totRegAssigned, ssym->key);
815 /* mark the registers as free */
816 for (i = 0; i < ssym->nRegs; i++)
818 hc08_freeReg (ssym->regs[i]);
820 /* if spilt on stack then free up hx
821 if it could have been assigned to as gprs */
822 if (!hc08_ptrRegReq && isSpiltOnStack (ssym))
825 spillLRWithPtrReg (ssym);
828 /* if this was a block level spil then insert push & pop
829 at the start & end of block respectively */
832 iCode *nic = newiCode (IPUSH, operandFromSymbol (ssym), NULL);
833 /* add push to the start of the block */
834 addiCodeToeBBlock (ebp, nic, (ebp->sch->op == LABEL ?
835 ebp->sch->next : ebp->sch));
836 nic = newiCode (IPOP, operandFromSymbol (ssym), NULL);
837 /* add pop to the end of the block */
838 addiCodeToeBBlock (ebp, nic, NULL);
841 /* if spilt because not used in the remainder of the
842 block then add a push before this instruction and
843 a pop at the end of the block */
844 if (ssym->remainSpil)
847 iCode *nic = newiCode (IPUSH, operandFromSymbol (ssym), NULL);
848 /* add push just before this instruction */
849 addiCodeToeBBlock (ebp, nic, ic);
851 nic = newiCode (IPOP, operandFromSymbol (ssym), NULL);
852 /* add pop to the end of the block */
853 addiCodeToeBBlock (ebp, nic, NULL);
862 /*-----------------------------------------------------------------*/
863 /* getRegPtr - will try for PTR if not a GPR type if not spil */
864 /*-----------------------------------------------------------------*/
866 getRegPtr (iCode * ic, eBBlock * ebp, symbol * sym)
871 /* try for a ptr type */
872 if ((reg = allocReg (REG_PTR)))
875 /* try for gpr type */
876 if ((reg = allocReg (REG_GPR)))
879 /* we have to spil */
880 if (!spilSomething (ic, ebp, sym))
883 /* this looks like an infinite loop but
884 in really selectSpil will abort */
888 /*-----------------------------------------------------------------*/
889 /* getRegGpr - will try for GPR if not spil */
890 /*-----------------------------------------------------------------*/
892 getRegGpr (iCode * ic, eBBlock * ebp, symbol * sym)
897 /* try for gpr type */
898 if ((reg = allocReg (REG_GPR)))
902 if ((reg = allocReg (REG_PTR)))
905 /* we have to spil */
906 if (!spilSomething (ic, ebp, sym))
909 /* this looks like an infinite loop but
910 in really selectSpil will abort */
914 /*-----------------------------------------------------------------*/
915 /* getRegPtrNoSpil - get it cannot split */
916 /*-----------------------------------------------------------------*/
917 static regs *getRegPtrNoSpil()
921 /* try for a ptr type */
922 if ((reg = allocReg (REG_PTR)))
925 /* try for gpr type */
926 if ((reg = allocReg (REG_GPR)))
931 /* just to make the compiler happy */
935 /*-----------------------------------------------------------------*/
936 /* getRegGprNoSpil - get it cannot split */
937 /*-----------------------------------------------------------------*/
938 static regs *getRegGprNoSpil()
942 if ((reg = allocReg (REG_GPR)))
946 if ((reg = allocReg (REG_PTR)))
951 /* just to make the compiler happy */
955 /*-----------------------------------------------------------------*/
956 /* symHasReg - symbol has a given register */
957 /*-----------------------------------------------------------------*/
959 symHasReg (symbol * sym, regs * reg)
963 for (i = 0; i < sym->nRegs; i++)
964 if (sym->regs[i] == reg)
970 /*-----------------------------------------------------------------*/
971 /* deassignLRs - check the live to and if they have registers & are */
972 /* not spilt then free up the registers */
973 /*-----------------------------------------------------------------*/
975 deassignLRs (iCode * ic, eBBlock * ebp)
981 for (sym = hTabFirstItem (liveRanges, &k); sym;
982 sym = hTabNextItem (liveRanges, &k))
986 /* if it does not end here */
987 if (sym->liveTo > ic->seq)
990 /* if it was spilt on stack then we can
991 mark the stack spil location as free */
996 sym->usl.spillLoc->isFree = 1;
1002 if (!bitVectBitValue (_G.regAssigned, sym->key))
1005 /* special case check if this is an IFX &
1006 the privious one was a pop and the
1007 previous one was not spilt then keep track
1009 if (ic->op == IFX && ic->prev &&
1010 ic->prev->op == IPOP &&
1011 !ic->prev->parmPush &&
1012 !OP_SYMBOL (IC_LEFT (ic->prev))->isspilt)
1013 psym = OP_SYMBOL (IC_LEFT (ic->prev));
1019 bitVectUnSetBit (_G.regAssigned, sym->key);
1021 /* if the result of this one needs registers
1022 and does not have it then assign it right
1024 if (IC_RESULT (ic) &&
1025 !(SKIP_IC2 (ic) || /* not a special icode */
1026 ic->op == JUMPTABLE ||
1031 POINTER_SET (ic)) &&
1032 (result = OP_SYMBOL (IC_RESULT (ic))) && /* has a result */
1033 result->liveTo > ic->seq && /* and will live beyond this */
1034 result->liveTo <= ebp->lSeq && /* does not go beyond this block */
1035 result->regType == sym->regType && /* same register types */
1036 result->nRegs && /* which needs registers */
1037 !result->isspilt && /* and does not already have them */
1039 !bitVectBitValue (_G.regAssigned, result->key) &&
1040 /* the number of free regs + number of regs in this LR
1041 can accomodate the what result Needs */
1042 ((nfreeRegsType (result->regType) +
1043 sym->nRegs) >= result->nRegs)
1047 for (i = 0; i < result->nRegs; i++)
1049 result->regs[i] = sym->regs[i];
1051 result->regs[i] = getRegGpr (ic, ebp, result);
1053 _G.regAssigned = bitVectSetBit (_G.regAssigned, result->key);
1054 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, result->key);
1058 /* free the remaining */
1059 for (; i < sym->nRegs; i++)
1063 if (!symHasReg (psym, sym->regs[i]))
1064 hc08_freeReg (sym->regs[i]);
1067 hc08_freeReg (sym->regs[i]);
1074 /*-----------------------------------------------------------------*/
1075 /* reassignLR - reassign this to registers */
1076 /*-----------------------------------------------------------------*/
1078 reassignLR (operand * op)
1080 symbol *sym = OP_SYMBOL (op);
1083 /* not spilt any more */
1084 sym->isspilt = sym->spillA = sym->blockSpil = sym->remainSpil = 0;
1085 bitVectUnSetBit (_G.spiltSet, sym->key);
1087 _G.regAssigned = bitVectSetBit (_G.regAssigned, sym->key);
1088 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, sym->key);
1092 for (i = 0; i < sym->nRegs; i++)
1093 sym->regs[i]->isFree = 0;
1096 /*-----------------------------------------------------------------*/
1097 /* willCauseSpill - determines if allocating will cause a spill */
1098 /*-----------------------------------------------------------------*/
1100 willCauseSpill (int nr, int rt)
1102 /* first check if there are any avlb registers
1103 of te type required */
1106 /* special case for pointer type
1107 if pointer type not avlb then
1108 check for type gpr */
1109 if (nFreeRegs (rt) >= nr)
1111 if (nFreeRegs (REG_GPR) >= nr)
1118 if (nFreeRegs (rt) >= nr)
1123 if (nFreeRegs (REG_PTR) +
1124 nFreeRegs (REG_GPR) >= nr)
1129 /* it will cause a spil */
1133 /*-----------------------------------------------------------------*/
1134 /* positionRegs - the allocator can allocate same registers to res- */
1135 /* ult and operand, if this happens make sure they are in the same */
1136 /* position as the operand otherwise chaos results */
1137 /*-----------------------------------------------------------------*/
1139 positionRegs (symbol * result, symbol * opsym)
1141 int count = min (result->nRegs, opsym->nRegs);
1142 int i, j = 0, shared = 0;
1145 /* if the result has been spilt then cannot share */
1150 /* first make sure that they actually share */
1151 for (i = 0; i < count; i++)
1153 for (j = 0; j < count; j++)
1155 if (result->regs[i] == opsym->regs[j] && i != j)
1165 regs *tmp = result->regs[i];
1166 result->regs[i] = result->regs[j];
1167 result->regs[j] = tmp;
1174 /*------------------------------------------------------------------*/
1175 /* verifyRegsAssigned - make sure an iTemp is properly initialized; */
1176 /* it should either have registers or have beed spilled. Otherwise, */
1177 /* there was an uninitialized variable, so just spill this to get */
1178 /* the operand in a valid state. */
1179 /*------------------------------------------------------------------*/
1181 verifyRegsAssigned (operand *op, iCode * ic)
1186 if (!IS_ITEMP (op)) return;
1188 sym = OP_SYMBOL (op);
1189 if (sym->isspilt) return;
1190 if (!sym->nRegs) return;
1191 if (sym->regs[0]) return;
1193 werrorfl (ic->filename, ic->lineno, W_LOCAL_NOINIT,
1194 sym->prereqv ? sym->prereqv->name : sym->name);
1200 /*-----------------------------------------------------------------*/
1201 /* serialRegAssign - serially allocate registers to the variables */
1202 /*-----------------------------------------------------------------*/
1204 serialRegAssign (eBBlock ** ebbs, int count)
1208 /* for all blocks */
1209 for (i = 0; i < count; i++) {
1213 if (ebbs[i]->noPath &&
1214 (ebbs[i]->entryLabel != entryLabel &&
1215 ebbs[i]->entryLabel != returnLabel))
1218 /* of all instructions do */
1219 for (ic = ebbs[i]->sch; ic; ic = ic->next) {
1223 // update the registers in use at the start of this icode
1224 for (reg=0; reg<hc08_nRegs; reg++) {
1225 if (regshc08[reg].isFree) {
1226 ic->riu &= ~(regshc08[reg].mask);
1228 ic->riu |= (regshc08[reg].mask);
1233 /* if this is an ipop that means some live
1234 range will have to be assigned again */
1236 reassignLR (IC_LEFT (ic));
1238 /* if result is present && is a true symbol */
1239 if (IC_RESULT (ic) && ic->op != IFX &&
1240 IS_TRUE_SYMOP (IC_RESULT (ic)))
1241 OP_SYMBOL (IC_RESULT (ic))->allocreq++;
1243 /* take away registers from live
1244 ranges that end at this instruction */
1245 deassignLRs (ic, ebbs[i]);
1247 /* some don't need registers */
1248 if (SKIP_IC2 (ic) ||
1249 ic->op == JUMPTABLE ||
1253 (IC_RESULT (ic) && POINTER_SET (ic)))
1256 /* now we need to allocate registers
1257 only for the result */
1258 if (IC_RESULT (ic)) {
1259 symbol *sym = OP_SYMBOL (IC_RESULT (ic));
1265 /* if it does not need or is spilt
1266 or is already assigned to registers
1267 or will not live beyond this instructions */
1270 bitVectBitValue (_G.regAssigned, sym->key) ||
1271 sym->liveTo <= ic->seq)
1274 /* if some liverange has been spilt at the block level
1275 and this one live beyond this block then spil this
1277 if (_G.blockSpil && sym->liveTo > ebbs[i]->lSeq) {
1281 /* if trying to allocate this will cause
1282 a spill and there is nothing to spill
1283 or this one is rematerializable then
1285 willCS = willCauseSpill (sym->nRegs, sym->regType);
1286 spillable = computeSpillable (ic);
1287 if (sym->remat || (willCS && bitVectIsZero (spillable))) {
1292 /* if it has a spillocation & is used less than
1293 all other live ranges then spill this */
1295 if (sym->usl.spillLoc) {
1296 symbol *leastUsed = leastUsedLR (liveRangesWith (spillable,
1297 allLRs, ebbs[i], ic));
1298 if (leastUsed && leastUsed->used > sym->used) {
1303 /* if none of the liveRanges have a spillLocation then better
1304 to spill this one than anything else already assigned to registers */
1305 if (liveRangesWith(spillable,noSpilLoc,ebbs[i],ic)) {
1306 /* if this is local to this block then we might find a block spil */
1307 if (!(sym->liveFrom >= ebbs[i]->fSeq && sym->liveTo <= ebbs[i]->lSeq)) {
1314 /* if we need ptr regs for the right side
1316 if (POINTER_GET (ic) && IS_SYMOP (IC_LEFT (ic))
1317 && getSize (OP_SYMBOL (IC_LEFT (ic))->type) <= (unsigned int) PTRSIZE) {
1321 /* else we assign registers to it */
1322 _G.regAssigned = bitVectSetBit (_G.regAssigned, sym->key);
1323 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, sym->key);
1325 for (j = 0; j < sym->nRegs; j++) {
1326 if (sym->regType == REG_PTR)
1327 sym->regs[j] = getRegPtr (ic, ebbs[i], sym);
1329 sym->regs[j] = getRegGpr (ic, ebbs[i], sym);
1331 /* if the allocation failed which means
1332 this was spilt then break */
1333 if (!sym->regs[j]) {
1338 /* if it shares registers with operands make sure
1339 that they are in the same position */
1340 if (IC_LEFT (ic) && IS_SYMOP (IC_LEFT (ic)) &&
1341 OP_SYMBOL (IC_LEFT (ic))->nRegs && ic->op != '=') {
1342 positionRegs (OP_SYMBOL (IC_RESULT (ic)),
1343 OP_SYMBOL (IC_LEFT (ic)));
1345 /* do the same for the right operand */
1346 if (IC_RIGHT (ic) && IS_SYMOP (IC_RIGHT (ic)) &&
1347 OP_SYMBOL (IC_RIGHT (ic))->nRegs) {
1348 positionRegs (OP_SYMBOL (IC_RESULT (ic)),
1349 OP_SYMBOL (IC_RIGHT (ic)));
1361 /* Check for and fix any problems with uninitialized operands */
1362 for (i = 0; i < count; i++)
1366 if (ebbs[i]->noPath &&
1367 (ebbs[i]->entryLabel != entryLabel &&
1368 ebbs[i]->entryLabel != returnLabel))
1371 for (ic = ebbs[i]->sch; ic; ic = ic->next)
1378 verifyRegsAssigned (IC_COND (ic), ic);
1382 if (ic->op == JUMPTABLE)
1384 verifyRegsAssigned (IC_JTCOND (ic), ic);
1388 verifyRegsAssigned (IC_RESULT (ic), ic);
1389 verifyRegsAssigned (IC_LEFT (ic), ic);
1390 verifyRegsAssigned (IC_RIGHT (ic), ic);
1396 /*-----------------------------------------------------------------*/
1397 /* fillGaps - Try to fill in the Gaps left by Pass1 */
1398 /*-----------------------------------------------------------------*/
1399 static void fillGaps()
1404 if (getenv("DISABLE_FILL_GAPS")) return;
1406 /* look for livernages that was spilt by the allocator */
1407 for (sym = hTabFirstItem(liveRanges,&key) ; sym ;
1408 sym = hTabNextItem(liveRanges,&key)) {
1413 if (!sym->spillA || !sym->clashes || sym->remat) continue ;
1415 /* find the liveRanges this one clashes with, that are
1416 still assigned to registers & mark the registers as used*/
1417 for ( i = 0 ; i < sym->clashes->size ; i ++) {
1421 if (bitVectBitValue(sym->clashes,i) == 0 || /* those that clash with this */
1422 bitVectBitValue(_G.totRegAssigned,i) == 0) /* and are still assigned to registers */
1425 clr = hTabItemWithKey(liveRanges,i);
1428 /* mark these registers as used */
1429 for (k = 0 ; k < clr->nRegs ; k++ )
1430 hc08_useReg(clr->regs[k]);
1433 if (willCauseSpill(sym->nRegs,sym->regType)) {
1434 /* NOPE :( clear all registers & and continue */
1439 /* THERE IS HOPE !!!! */
1440 for (i=0; i < sym->nRegs ; i++ ) {
1441 if (sym->regType == REG_PTR)
1442 sym->regs[i] = getRegPtrNoSpil ();
1444 sym->regs[i] = getRegGprNoSpil ();
1447 /* for all its definitions check if the registers
1448 allocated needs positioning NOTE: we can position
1449 only ONCE if more than One positioning required
1452 for (i = 0 ; i < sym->defs->size ; i++ ) {
1453 if (bitVectBitValue(sym->defs,i)) {
1455 if (!(ic = hTabItemWithKey(iCodehTab,i))) continue ;
1456 if (SKIP_IC(ic)) continue;
1457 assert(isSymbolEqual(sym,OP_SYMBOL(IC_RESULT(ic)))); /* just making sure */
1458 /* if left is assigned to registers */
1459 if (IS_SYMOP(IC_LEFT(ic)) &&
1460 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_LEFT(ic))->key)) {
1461 pdone += positionRegs(sym,OP_SYMBOL(IC_LEFT(ic)));
1463 if (IS_SYMOP(IC_RIGHT(ic)) &&
1464 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_RIGHT(ic))->key)) {
1465 pdone += positionRegs(sym,OP_SYMBOL(IC_RIGHT(ic)));
1467 if (pdone > 1) break;
1470 for (i = 0 ; i < sym->uses->size ; i++ ) {
1471 if (bitVectBitValue(sym->uses,i)) {
1473 if (!(ic = hTabItemWithKey(iCodehTab,i))) continue ;
1474 if (SKIP_IC(ic)) continue;
1475 if (!IS_ASSIGN_ICODE(ic)) continue ;
1477 /* if result is assigned to registers */
1478 if (IS_SYMOP(IC_RESULT(ic)) &&
1479 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_RESULT(ic))->key)) {
1480 pdone += positionRegs(sym,OP_SYMBOL(IC_RESULT(ic)));
1482 if (pdone > 1) break;
1485 /* had to position more than once GIVE UP */
1487 /* UNDO all the changes we made to try this */
1489 for (i=0; i < sym->nRegs ; i++ ) {
1490 sym->regs[i] = NULL;
1493 D(printf ("Fill Gap gave up due to positioning for %s in function %s\n",sym->name, currFunc ? currFunc->name : "UNKNOWN"));
1496 D(printf ("FILLED GAP for %s in function %s\n",sym->name, currFunc ? currFunc->name : "UNKNOWN"));
1497 _G.totRegAssigned = bitVectSetBit(_G.totRegAssigned,sym->key);
1498 sym->isspilt = sym->spillA = 0 ;
1499 sym->usl.spillLoc->allocreq--;
1504 /*-----------------------------------------------------------------*/
1505 /* rUmaskForOp :- returns register mask for an operand */
1506 /*-----------------------------------------------------------------*/
1508 hc08_rUmaskForOp (operand * op)
1514 /* only temporaries are assigned registers */
1518 sym = OP_SYMBOL (op);
1520 /* if spilt or no registers assigned to it
1522 if (sym->isspilt || !sym->nRegs)
1525 rumask = newBitVect (hc08_nRegs);
1527 for (j = 0; j < sym->nRegs; j++)
1529 rumask = bitVectSetBit (rumask,
1530 sym->regs[j]->rIdx);
1536 /*-----------------------------------------------------------------*/
1537 /* regsUsedIniCode :- returns bit vector of registers used in iCode */
1538 /*-----------------------------------------------------------------*/
1540 regsUsedIniCode (iCode * ic)
1542 bitVect *rmask = newBitVect (hc08_nRegs);
1544 /* do the special cases first */
1547 rmask = bitVectUnion (rmask,
1548 hc08_rUmaskForOp (IC_COND (ic)));
1552 /* for the jumptable */
1553 if (ic->op == JUMPTABLE)
1555 rmask = bitVectUnion (rmask,
1556 hc08_rUmaskForOp (IC_JTCOND (ic)));
1561 /* of all other cases */
1563 rmask = bitVectUnion (rmask,
1564 hc08_rUmaskForOp (IC_LEFT (ic)));
1568 rmask = bitVectUnion (rmask,
1569 hc08_rUmaskForOp (IC_RIGHT (ic)));
1572 rmask = bitVectUnion (rmask,
1573 hc08_rUmaskForOp (IC_RESULT (ic)));
1579 /*-----------------------------------------------------------------*/
1580 /* createRegMask - for each instruction will determine the regsUsed */
1581 /*-----------------------------------------------------------------*/
1583 createRegMask (eBBlock ** ebbs, int count)
1587 /* for all blocks */
1588 for (i = 0; i < count; i++)
1592 if (ebbs[i]->noPath &&
1593 (ebbs[i]->entryLabel != entryLabel &&
1594 ebbs[i]->entryLabel != returnLabel))
1597 /* for all instructions */
1598 for (ic = ebbs[i]->sch; ic; ic = ic->next)
1603 if (SKIP_IC2 (ic) || !ic->rlive)
1606 /* first mark the registers used in this
1608 ic->rUsed = regsUsedIniCode (ic);
1609 _G.funcrUsed = bitVectUnion (_G.funcrUsed, ic->rUsed);
1611 /* now create the register mask for those
1612 registers that are in use : this is a
1613 super set of ic->rUsed */
1614 ic->rMask = newBitVect (hc08_nRegs + 1);
1616 /* for all live Ranges alive at this point */
1617 for (j = 1; j < ic->rlive->size; j++)
1622 /* if not alive then continue */
1623 if (!bitVectBitValue (ic->rlive, j))
1626 /* find the live range we are interested in */
1627 if (!(sym = hTabItemWithKey (liveRanges, j)))
1629 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
1630 "createRegMask cannot find live range");
1631 fprintf(stderr, "\tmissing live range: key=%d\n", j);
1635 /* if no register assigned to it */
1636 if (!sym->nRegs || sym->isspilt)
1639 /* for all the registers allocated to it */
1640 for (k = 0; k < sym->nRegs; k++)
1643 bitVectSetBit (ic->rMask, sym->regs[k]->rIdx);
1649 /*-----------------------------------------------------------------*/
1650 /* rematStr - returns the rematerialized string for a remat var */
1651 /*-----------------------------------------------------------------*/
1653 rematStr (symbol * sym)
1656 iCode *ic = sym->rematiCode;
1661 /* if plus or minus print the right hand side */
1662 if (ic->op == '+' || ic->op == '-')
1664 sprintf (s, "0x%04x %c ", (int) operandLitValue (IC_RIGHT (ic)),
1667 ic = OP_SYMBOL (IC_LEFT (ic))->rematiCode;
1674 offset += operandLitValue (IC_RIGHT (ic));
1675 ic = OP_SYMBOL (IC_LEFT (ic))->rematiCode;
1680 offset -= operandLitValue (IC_RIGHT (ic));
1681 ic = OP_SYMBOL (IC_LEFT (ic))->rematiCode;
1685 /* cast then continue */
1686 if (IS_CAST_ICODE(ic)) {
1687 ic = OP_SYMBOL (IC_RIGHT (ic))->rematiCode;
1690 /* we reached the end */
1691 if (ic->op == ADDRESS_OF)
1692 sprintf (s, "%s", OP_SYMBOL (IC_LEFT (ic))->rname);
1693 else if (ic->op == '=')
1694 sprintf (s, "0x%04x", (int) operandLitValue (IC_RIGHT (ic)) );
1701 /*-----------------------------------------------------------------*/
1702 /* regTypeNum - computes the type & number of registers required */
1703 /*-----------------------------------------------------------------*/
1705 regTypeNum (eBBlock *ebbs)
1711 /* for each live range do */
1712 for (sym = hTabFirstItem (liveRanges, &k); sym;
1713 sym = hTabNextItem (liveRanges, &k))
1716 /* if used zero times then no registers needed */
1717 if ((sym->liveTo - sym->liveFrom) == 0)
1721 /* if the live range is a temporary */
1725 /* if the type is marked as a conditional */
1726 if (sym->regType == REG_CND)
1729 /* if used in return only then we don't
1731 if (sym->ruonly || sym->accuse)
1733 if (IS_AGGREGATE (sym->type) || sym->isptr)
1734 sym->type = aggrToPtr (sym->type, FALSE);
1738 /* if the symbol has only one definition &
1739 that definition is a get_pointer */
1740 if (bitVectnBitsOn (sym->defs) == 1 &&
1741 (ic = hTabItemWithKey (iCodehTab,
1742 bitVectFirstBit (sym->defs))) &&
1744 !IS_BITVAR (sym->etype) &&
1745 (aggrToPtrDclType (operandType (IC_LEFT (ic)), FALSE) == POINTER))
1748 if (ptrPseudoSymSafe (sym, ic))
1750 ptrPseudoSymConvert (sym, ic, rematStr (OP_SYMBOL (IC_LEFT (ic))));
1754 /* if in data space or idata space then try to
1755 allocate pointer register */
1759 /* if not then we require registers */
1760 sym->nRegs = ((IS_AGGREGATE (sym->type) || sym->isptr) ?
1761 getSize (sym->type = aggrToPtr (sym->type, FALSE)) :
1762 getSize (sym->type));
1766 fprintf (stderr, "allocated more than 4 or 0 registers for type ");
1767 printTypeChain (sym->type, stderr);
1768 fprintf (stderr, "\n");
1771 /* determine the type of register required */
1772 if (sym->nRegs == 1 &&
1773 IS_PTR (sym->type) &&
1775 sym->regType = REG_PTR;
1777 sym->regType = REG_GPR;
1781 /* for the first run we don't provide */
1782 /* registers for true symbols we will */
1783 /* see how things go */
1789 /*-----------------------------------------------------------------*/
1790 /* freeAllRegs - mark all registers as free */
1791 /*-----------------------------------------------------------------*/
1797 for (i = 0; i < hc08_nRegs; i++) {
1798 regshc08[i].isFree = 1;
1799 regshc08[i].aop = NULL;
1803 /*-----------------------------------------------------------------*/
1804 /* deallocStackSpil - this will set the stack pointer back */
1805 /*-----------------------------------------------------------------*/
1807 DEFSETFUNC (deallocStackSpil)
1816 /*-----------------------------------------------------------------*/
1817 /* farSpacePackable - returns the packable icode for far variables */
1818 /*-----------------------------------------------------------------*/
1820 farSpacePackable (iCode * ic)
1824 /* go thru till we find a definition for the
1825 symbol on the right */
1826 for (dic = ic->prev; dic; dic = dic->prev)
1828 /* if the definition is a call then no */
1829 if ((dic->op == CALL || dic->op == PCALL) &&
1830 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1835 /* if shift by unknown amount then not */
1836 if ((dic->op == LEFT_OP || dic->op == RIGHT_OP) &&
1837 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1841 /* if pointer get and size > 1 */
1842 if (POINTER_GET (dic) &&
1843 getSize (aggrToPtr (operandType (IC_LEFT (dic)), FALSE)) > 1)
1846 if (POINTER_SET (dic) &&
1847 getSize (aggrToPtr (operandType (IC_RESULT (dic)), FALSE)) > 1)
1851 /* if any three is a true symbol in far space */
1852 if (IC_RESULT (dic) &&
1853 IS_TRUE_SYMOP (IC_RESULT (dic)) /* &&
1854 isOperandInFarSpace (IC_RESULT (dic)) */)
1857 if (IC_RIGHT (dic) &&
1858 IS_TRUE_SYMOP (IC_RIGHT (dic)) /* &&
1859 isOperandInFarSpace (IC_RIGHT (dic)) */ &&
1860 !isOperandEqual (IC_RIGHT (dic), IC_RESULT (ic)))
1863 if (IC_LEFT (dic) &&
1864 IS_TRUE_SYMOP (IC_LEFT (dic)) /* &&
1865 isOperandInFarSpace (IC_LEFT (dic)) */ &&
1866 !isOperandEqual (IC_LEFT (dic), IC_RESULT (ic)))
1869 if (isOperandEqual (IC_RIGHT (ic), IC_RESULT (dic)))
1871 if ((dic->op == LEFT_OP ||
1872 dic->op == RIGHT_OP ||
1874 IS_OP_LITERAL (IC_RIGHT (dic)))
1887 packRegsForLiteral (iCode * ic)
1894 if (POINTER_SET (ic))
1896 if (!IS_LITERAL (getSpec (operandType (IC_RIGHT (ic)))))
1898 if (bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) > 1)
1901 for (k=0; k< OP_USES (IC_RESULT (ic))->size; k++)
1902 if (bitVectBitValue (OP_USES (IC_RESULT (ic)), k))
1904 uic = hTabItemWithKey (iCodehTab, k);
1907 if (uic->op != IFX && uic->op != JUMPTABLE)
1909 if (IC_LEFT (uic) && IC_LEFT (uic)->key == IC_RESULT (ic)->key)
1910 ReplaceOpWithCheaperOp(&IC_LEFT(uic), IC_RIGHT(ic));
1911 if (IC_RIGHT (uic) && IC_RIGHT (uic)->key == IC_RESULT (ic)->key)
1912 ReplaceOpWithCheaperOp(&IC_RIGHT(uic), IC_RIGHT(ic));
1913 if (IC_RESULT (uic) && IC_RESULT (uic)->key == IC_RESULT (ic)->key)
1914 ReplaceOpWithCheaperOp(&IC_RESULT(uic), IC_RIGHT(ic));
1922 /*-----------------------------------------------------------------*/
1923 /* packRegsForAssign - register reduction for assignment */
1924 /*-----------------------------------------------------------------*/
1926 packRegsForAssign (iCode * ic, eBBlock * ebp)
1930 if (!IS_ITEMP (IC_RIGHT (ic)) ||
1931 OP_SYMBOL (IC_RIGHT (ic))->isind ||
1932 OP_LIVETO (IC_RIGHT (ic)) > ic->seq)
1938 /* if the true symbol is defined in far space or on stack
1939 then we should not since this will increase register pressure */
1941 if (isOperandInFarSpace(IC_RESULT(ic)) && !farSpacePackable(ic)) {
1946 /* find the definition of iTempNN scanning backwards if we find a
1947 a use of the true symbol in before we find the definition then
1949 for (dic = ic->prev; dic; dic = dic->prev)
1952 #if 0 /* jwk: This collides with 1.43 but I really see no need for
1953 this anymore. It fixes bug #716790 and substantially improves
1954 redundant register usage around function calls.
1957 /* if there is a function call then don't pack it */
1958 if ((dic->op == CALL || dic->op == PCALL))
1968 if (IS_TRUE_SYMOP (IC_RESULT (dic)) &&
1969 IS_OP_VOLATILE (IC_RESULT (dic)))
1975 if (IS_SYMOP (IC_RESULT (dic)) &&
1976 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1978 if (POINTER_SET (dic))
1984 if (IS_SYMOP (IC_RIGHT (dic)) &&
1985 (IC_RIGHT (dic)->key == IC_RESULT (ic)->key ||
1986 IC_RIGHT (dic)->key == IC_RIGHT (ic)->key))
1992 if (IS_SYMOP (IC_LEFT (dic)) &&
1993 (IC_LEFT (dic)->key == IC_RESULT (ic)->key ||
1994 IC_LEFT (dic)->key == IC_RIGHT (ic)->key))
2000 if (POINTER_SET (dic) &&
2001 IC_RESULT (dic)->key == IC_RESULT (ic)->key)
2009 return 0; /* did not find */
2011 /* if assignment then check that right is not a bit */
2012 if (ASSIGNMENT (dic) && !POINTER_SET (dic))
2014 sym_link *etype = operandType (IC_RIGHT (dic));
2015 if (IS_BITFIELD (etype))
2017 /* if result is a bit too then it's ok */
2018 etype = operandType (IC_RESULT (dic));
2019 if (!IS_BITFIELD (etype))
2023 /* if the result is on stack or iaccess then it must be
2024 the same atleast one of the operands */
2025 if (OP_SYMBOL (IC_RESULT (ic))->onStack ||
2026 OP_SYMBOL (IC_RESULT (ic))->iaccess)
2029 /* the operation has only one symbol
2030 operator then we can pack */
2031 if ((IC_LEFT (dic) && !IS_SYMOP (IC_LEFT (dic))) ||
2032 (IC_RIGHT (dic) && !IS_SYMOP (IC_RIGHT (dic))))
2035 if (!((IC_LEFT (dic) &&
2036 IC_RESULT (ic)->key == IC_LEFT (dic)->key) ||
2038 IC_RESULT (ic)->key == IC_RIGHT (dic)->key)))
2042 /* found the definition */
2043 /* replace the result with the result of */
2044 /* this assignment and remove this assignment */
2045 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2046 ReplaceOpWithCheaperOp(&IC_RESULT (dic), IC_RESULT (ic));
2048 if (IS_ITEMP (IC_RESULT (dic)) && OP_SYMBOL (IC_RESULT (dic))->liveFrom > dic->seq)
2050 OP_SYMBOL (IC_RESULT (dic))->liveFrom = dic->seq;
2052 // TODO: and the otherway around?
2054 /* delete from liverange table also
2055 delete from all the points inbetween and the new
2057 for (sic = dic; sic != ic; sic = sic->next)
2059 bitVectUnSetBit (sic->rlive, IC_RESULT (ic)->key);
2060 if (IS_ITEMP (IC_RESULT (dic)))
2061 bitVectSetBit (sic->rlive, IC_RESULT (dic)->key);
2064 remiCodeFromeBBlock (ebp, ic);
2065 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
2066 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
2067 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
2072 /*------------------------------------------------------------------*/
2073 /* findAssignToSym : scanning backwards looks for first assig found */
2074 /*------------------------------------------------------------------*/
2076 findAssignToSym (operand * op, iCode * ic)
2080 /* This routine is used to find sequences like
2082 ...; (intervening ops don't use iTempAA or modify FOO)
2083 blah = blah + iTempAA;
2085 and eliminate the use of iTempAA, freeing up its register for
2090 for (dic = ic->prev; dic; dic = dic->prev)
2093 /* if definition by assignment */
2094 if (dic->op == '=' &&
2095 !POINTER_SET (dic) &&
2096 IC_RESULT (dic)->key == op->key
2097 && IS_TRUE_SYMOP(IC_RIGHT(dic))
2099 break; /* found where this temp was defined */
2101 /* if we find an usage then we cannot delete it */
2102 if (IC_LEFT (dic) && IC_LEFT (dic)->key == op->key)
2105 if (IC_RIGHT (dic) && IC_RIGHT (dic)->key == op->key)
2108 if (POINTER_SET (dic) && IC_RESULT (dic)->key == op->key)
2113 return NULL; /* didn't find any assignment to op */
2115 /* we are interested only if defined in far space */
2116 /* or in stack space in case of + & - */
2118 /* if assigned to a non-symbol then don't repack regs */
2119 if (!IS_SYMOP (IC_RIGHT (dic)))
2122 /* if the symbol is volatile then we should not */
2123 if (isOperandVolatile (IC_RIGHT (dic), TRUE))
2125 /* XXX TODO --- should we be passing FALSE to isOperandVolatile()?
2126 What does it mean for an iTemp to be volatile, anyway? Passing
2127 TRUE is more cautious but may prevent possible optimizations */
2129 /* if the symbol is in far space then we should not */
2130 /* if (isOperandInFarSpace (IC_RIGHT (dic)))
2133 /* for + & - operations make sure that
2134 if it is on the stack it is the same
2135 as one of the three operands */
2137 if ((ic->op == '+' || ic->op == '-') &&
2138 OP_SYMBOL (IC_RIGHT (dic))->onStack)
2141 if (IC_RESULT (ic)->key != IC_RIGHT (dic)->key &&
2142 IC_LEFT (ic)->key != IC_RIGHT (dic)->key &&
2143 IC_RIGHT (ic)->key != IC_RIGHT (dic)->key)
2148 /* now make sure that the right side of dic
2149 is not defined between ic & dic */
2152 iCode *sic = dic->next;
2154 for (; sic != ic; sic = sic->next)
2155 if (IC_RESULT (sic) &&
2156 IC_RESULT (sic)->key == IC_RIGHT (dic)->key)
2163 /*-----------------------------------------------------------------*/
2164 /* reassignAliasedSym - used by packRegsForSupport to replace */
2165 /* redundant iTemp with equivalent symbol */
2166 /*-----------------------------------------------------------------*/
2168 reassignAliasedSym (eBBlock *ebp, iCode *assignment, iCode *use, operand *op)
2171 unsigned oldSymKey, newSymKey;
2173 oldSymKey = op->key;
2174 newSymKey = IC_RIGHT(assignment)->key;
2176 /* only track live ranges of compiler-generated temporaries */
2177 if (!IS_ITEMP(IC_RIGHT(assignment)))
2180 /* update the live-value bitmaps */
2181 for (ic = assignment; ic != use; ic = ic->next) {
2182 bitVectUnSetBit (ic->rlive, oldSymKey);
2184 ic->rlive = bitVectSetBit (ic->rlive, newSymKey);
2187 /* update the sym of the used operand */
2188 OP_SYMBOL(op) = OP_SYMBOL(IC_RIGHT(assignment));
2189 op->key = OP_SYMBOL(op)->key;
2191 /* update the sym's liverange */
2192 if ( OP_LIVETO(op) < ic->seq )
2193 setToRange(op, ic->seq, FALSE);
2195 /* remove the assignment iCode now that its result is unused */
2196 remiCodeFromeBBlock (ebp, assignment);
2197 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(assignment))->defs, assignment->key);
2198 hTabDeleteItem (&iCodehTab, assignment->key, assignment, DELETE_ITEM, NULL);
2202 /*-----------------------------------------------------------------*/
2203 /* packRegsForSupport :- reduce some registers for support calls */
2204 /*-----------------------------------------------------------------*/
2206 packRegsForSupport (iCode * ic, eBBlock * ebp)
2211 /* for the left & right operand :- look to see if the
2212 left was assigned a true symbol in far space in that
2213 case replace them */
2215 if (IS_ITEMP (IC_LEFT (ic)) &&
2216 OP_SYMBOL (IC_LEFT (ic))->liveTo <= ic->seq)
2218 dic = findAssignToSym (IC_LEFT (ic), ic);
2222 /* found it we need to remove it from the block */
2223 reassignAliasedSym (ebp, dic, ic, IC_LEFT(ic));
2228 /* do the same for the right operand */
2229 if (IS_ITEMP (IC_RIGHT (ic)) &&
2230 OP_SYMBOL (IC_RIGHT (ic))->liveTo <= ic->seq)
2232 iCode *dic = findAssignToSym (IC_RIGHT (ic), ic);
2236 /* found it we need to remove it from the block */
2237 reassignAliasedSym (ebp, dic, ic, IC_RIGHT(ic));
2245 #define IS_OP_RUONLY(x) (x && IS_SYMOP(x) && OP_SYMBOL(x)->ruonly)
2249 /*-----------------------------------------------------------------*/
2250 /* packRegsForOneuse : - will reduce some registers for single Use */
2251 /*-----------------------------------------------------------------*/
2253 packRegsForOneuse (iCode * ic, operand * op, eBBlock * ebp)
2258 /* if returning a literal then do nothing */
2262 /* only up to 2 bytes */
2263 if (getSize (operandType (op)) > (fReturnSizeHC08 - 2))
2268 if (ic->op != SEND //RETURN
2270 && !POINTER_SET (ic)
2271 && !POINTER_GET (ic) )
2274 if (ic->op == SEND && ic->argreg != 1) return NULL;
2276 /* this routine will mark the a symbol as used in one
2277 instruction use only && if the defintion is local
2278 (ie. within the basic block) && has only one definition &&
2279 that definiion is either a return value from a
2280 function or does not contain any variables in
2282 uses = bitVectCopy (OP_USES (op));
2283 bitVectUnSetBit (uses, ic->key); /* take away this iCode */
2284 if (!bitVectIsZero (uses)) /* has other uses */
2287 /* if it has only one defintion */
2288 if (bitVectnBitsOn (OP_DEFS (op)) > 1)
2289 return NULL; /* has more than one definition */
2291 /* get that definition */
2293 hTabItemWithKey (iCodehTab,
2294 bitVectFirstBit (OP_DEFS (op)))))
2297 /* if that only usage is a cast */
2298 if (dic->op == CAST) {
2299 /* to a bigger type */
2300 if (getSize(OP_SYM_TYPE(IC_RESULT(dic))) >
2301 getSize(OP_SYM_TYPE(IC_RIGHT(dic)))) {
2302 /* than we can not, since we cannot predict the usage of b & acc */
2307 /* found the definition now check if it is local */
2308 if (dic->seq < ebp->fSeq ||
2309 dic->seq > ebp->lSeq)
2310 return NULL; /* non-local */
2312 /* now check if it is the return from
2314 if (dic->op == CALL || dic->op == PCALL)
2316 if (ic->op != SEND && ic->op != RETURN &&
2317 !POINTER_SET(ic) && !POINTER_GET(ic))
2319 OP_SYMBOL (op)->ruonly = 1;
2326 /* otherwise check that the definition does
2327 not contain any symbols in far space */
2328 // if (isOperandInFarSpace (IC_LEFT (dic)) ||
2329 // isOperandInFarSpace (IC_RIGHT (dic)) ||
2330 // IS_OP_RUONLY (IC_LEFT (ic)) ||
2331 // IS_OP_RUONLY (IC_RIGHT (ic)))
2336 /* if pointer set then make sure the pointer
2339 if (POINTER_SET (dic) &&
2340 !IS_DATA_PTR (aggrToPtr (operandType (IC_RESULT (dic)), FALSE)))
2343 if (POINTER_GET (dic) &&
2344 !IS_DATA_PTR (aggrToPtr (operandType (IC_LEFT (dic)), FALSE)))
2350 /* also make sure the intervenening instructions
2351 don't have any thing in far space */
2352 for (dic = dic->next; dic && dic != ic && sic != ic; dic = dic->next)
2355 /* if there is an intervening function call then no */
2356 if (dic->op == CALL || dic->op == PCALL)
2358 /* if pointer set then make sure the pointer
2361 if (POINTER_SET (dic) &&
2362 !IS_DATA_PTR (aggrToPtr (operandType (IC_RESULT (dic)), FALSE)))
2365 if (POINTER_GET (dic) &&
2366 !IS_DATA_PTR (aggrToPtr (operandType (IC_LEFT (dic)), FALSE)))
2369 /* if address of & the result is remat the okay */
2370 if (dic->op == ADDRESS_OF &&
2371 OP_SYMBOL (IC_RESULT (dic))->remat)
2374 /* if operand has size of three or more & this
2375 operation is a '*','/' or '%' then 'b' may
2378 if ((dic->op == '%' || dic->op == '/' || dic->op == '*') &&
2379 getSize (operandType (op)) >= 3)
2383 /* if left or right or result is in far space */
2384 // if (isOperandInFarSpace (IC_LEFT (dic)) ||
2385 // isOperandInFarSpace (IC_RIGHT (dic)) ||
2386 // isOperandInFarSpace (IC_RESULT (dic)) ||
2387 // IS_OP_RUONLY (IC_LEFT (dic)) ||
2388 // IS_OP_RUONLY (IC_RIGHT (dic)) ||
2389 // IS_OP_RUONLY (IC_RESULT (dic)))
2393 // /* if left or right or result is on stack */
2394 // if (isOperandOnStack(IC_LEFT(dic)) ||
2395 // isOperandOnStack(IC_RIGHT(dic)) ||
2396 // isOperandOnStack(IC_RESULT(dic))) {
2401 OP_SYMBOL (op)->ruonly = 1;
2406 /*-----------------------------------------------------------------*/
2407 /* isBitwiseOptimizable - requirements of JEAN LOUIS VERN */
2408 /*-----------------------------------------------------------------*/
2410 isBitwiseOptimizable (iCode * ic)
2412 sym_link *ltype = getSpec (operandType (IC_LEFT (ic)));
2413 sym_link *rtype = getSpec (operandType (IC_RIGHT (ic)));
2415 /* bitwise operations are considered optimizable
2416 under the following conditions (Jean-Louis VERN)
2428 if (IS_LITERAL(rtype) ||
2429 (IS_BITVAR (ltype) && IN_BITSPACE (SPEC_OCLS (ltype))))
2435 /*-----------------------------------------------------------------*/
2436 /* isCommutativeOp - tests whether this op cares what order its */
2437 /* operands are in */
2438 /*-----------------------------------------------------------------*/
2439 bool isCommutativeOp2(unsigned int op)
2441 if (op == '+' || op == '*' || op == EQ_OP ||
2442 op == '^' || op == '|' || op == BITWISEAND)
2448 /*-----------------------------------------------------------------*/
2449 /* operandUsesAcc2 - determines whether the code generated for this */
2450 /* operand will have to use the accumulator */
2451 /*-----------------------------------------------------------------*/
2452 bool operandUsesAcc2(operand *op)
2458 symbol *sym = OP_SYMBOL(op);
2462 return TRUE; /* duh! */
2464 // if (IN_STACK(sym->etype) || sym->onStack ||
2465 // (SPIL_LOC(op) && SPIL_LOC(op)->onStack))
2466 // return TRUE; /* acc is used to calc stack offset */
2471 sym = SPIL_LOC(op); /* if spilled, look at spill location */
2473 return FALSE; /* more checks? */
2477 symspace = SPEC_OCLS(sym->etype);
2479 // if (sym->iaccess && symspace->paged)
2480 // return TRUE; /* must fetch paged indirect sym via accumulator */
2482 if (IN_BITSPACE(symspace))
2483 return TRUE; /* fetching bit vars uses the accumulator */
2485 if (IN_FARSPACE(symspace) || IN_CODESPACE(symspace))
2486 return TRUE; /* fetched via accumulator and dptr */
2492 /*-----------------------------------------------------------------*/
2493 /* packRegsForAccUse - pack registers for acc use */
2494 /*-----------------------------------------------------------------*/
2496 packRegsForAccUse (iCode * ic)
2500 /* if this is an aggregate, e.g. a one byte char array */
2501 if (IS_AGGREGATE(operandType(IC_RESULT(ic)))) {
2505 /* if we are calling a reentrant function that has stack parameters */
2507 if (ic->op == CALL &&
2508 IFFUNC_ISREENT(operandType(IC_LEFT(ic))) &&
2509 FUNC_HASSTACKPARM(operandType(IC_LEFT(ic))))
2512 if (ic->op == PCALL &&
2513 IFFUNC_ISREENT(operandType(IC_LEFT(ic))->next) &&
2514 FUNC_HASSTACKPARM(operandType(IC_LEFT(ic))->next))
2518 /* if + or - then it has to be one byte result */
2519 if ((ic->op == '+' || ic->op == '-')
2520 && getSize (operandType (IC_RESULT (ic))) > 1)
2524 /* if shift operation make sure right side is a literal */
2525 if (ic->op == RIGHT_OP &&
2526 (!isOperandLiteral (IC_RIGHT (ic)) ||
2527 (getSize (operandType (IC_RESULT (ic) )) > 1)))
2530 if (ic->op == LEFT_OP &&
2531 (!isOperandLiteral (IC_RIGHT (ic)) ||
2532 (getSize (operandType (IC_RESULT (ic) )) > 1)))
2535 if (IS_BITWISE_OP (ic) &&
2536 getSize (operandType (IC_RESULT (ic))) > 1)
2540 /* has only one definition */
2541 if (bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) > 1)
2544 /* has only one use */
2545 if (bitVectnBitsOn (OP_USES (IC_RESULT (ic))) > 1)
2548 /* and the usage immediately follows this iCode */
2549 if (!(uic = hTabItemWithKey (iCodehTab,
2550 bitVectFirstBit (OP_USES (IC_RESULT (ic))))))
2553 if (ic->next != uic)
2556 /* if it is a conditional branch then we definitely can */
2560 if (uic->op == JUMPTABLE)
2564 if (POINTER_SET (uic) &&
2565 getSize (aggrToPtr (operandType (IC_RESULT (uic)), FALSE)) > 1)
2569 /* if the usage is not is an assignment
2570 or an arithmetic / bitwise / shift operation then not */
2571 if (uic->op != '=' &&
2572 !IS_ARITHMETIC_OP (uic) &&
2573 !IS_BITWISE_OP (uic) &&
2574 (uic->op != LEFT_OP) &&
2575 (uic->op != RIGHT_OP) &&
2576 (uic->op != GETHBIT) &&
2577 (uic->op != RETURN) &&
2583 /* if used in ^ operation then make sure right is not a
2584 literal (WIML: Why is this?) */
2585 if (uic->op == '^' && isOperandLiteral (IC_RIGHT (uic)))
2588 /* if shift operation make sure right side is not a literal */
2589 /* WIML: Why is this? */
2590 if (uic->op == RIGHT_OP &&
2591 (isOperandLiteral (IC_RIGHT (uic)) ||
2592 getSize (operandType (IC_RESULT (uic))) > 1))
2594 if (uic->op == LEFT_OP &&
2595 (isOperandLiteral (IC_RIGHT (uic)) ||
2596 getSize (operandType (IC_RESULT (uic))) > 1))
2600 /* make sure that the result of this icode is not on the
2601 stack, since acc is used to compute stack offset */
2603 if (IS_TRUE_SYMOP (IC_RESULT (uic)) &&
2604 OP_SYMBOL (IC_RESULT (uic))->onStack)
2607 // if (isOperandOnStack(IC_RESULT(uic)))
2611 /* if the usage has only one operand then we can */
2612 if (IC_LEFT (uic) == NULL ||
2613 IC_RIGHT (uic) == NULL)
2617 /* if the other operand uses the accumulator then we cannot */
2618 if ( (IC_LEFT(uic)->key == IC_RESULT(ic)->key &&
2619 operandUsesAcc2(IC_RIGHT(uic))) ||
2620 (IC_RIGHT(uic)->key == IC_RESULT(ic)->key &&
2621 operandUsesAcc2(IC_LEFT(uic))) )
2624 /* make sure this is on the left side if not commutative */
2625 /* except for '-', which has been written to be able to
2626 handle reversed operands */
2627 if (!(isCommutativeOp2(ic->op) || ic->op == '-') &&
2628 IC_LEFT (uic)->key != IC_RESULT (ic)->key)
2633 // this is too dangerous and need further restrictions
2636 /* if one of them is a literal then we can */
2637 if ((IC_LEFT (uic) && IS_OP_LITERAL (IC_LEFT (uic))) ||
2638 (IC_RIGHT (uic) && IS_OP_LITERAL (IC_RIGHT (uic))))
2640 OP_SYMBOL (IC_RESULT (ic))->accuse = 1;
2647 if ((POINTER_GET(uic))
2648 || (ic->op == ADDRESS_OF && uic->op == '+' && IS_OP_LITERAL (IC_RIGHT (uic))))
2650 OP_SYMBOL (IC_RESULT (ic))->accuse = ACCUSE_HX;
2654 OP_SYMBOL (IC_RESULT (ic))->accuse = ACCUSE_XA;
2657 /*-----------------------------------------------------------------*/
2658 /* packForPush - hueristics to reduce iCode for pushing */
2659 /*-----------------------------------------------------------------*/
2661 packForPush (iCode * ic, eBBlock ** ebpp, int blockno)
2665 struct eBBlock * ebp=ebpp[blockno];
2667 if (ic->op != IPUSH || !IS_ITEMP (IC_LEFT (ic)))
2670 /* must have only definition & one usage */
2671 if (bitVectnBitsOn (OP_DEFS (IC_LEFT (ic))) != 1 ||
2672 bitVectnBitsOn (OP_USES (IC_LEFT (ic))) != 1)
2675 /* find the definition */
2676 if (!(dic = hTabItemWithKey (iCodehTab,
2677 bitVectFirstBit (OP_DEFS (IC_LEFT (ic))))))
2680 if (dic->op != '=' || POINTER_SET (dic))
2683 if (dic->seq < ebp->fSeq) { // Evelyn did this
2685 for (i=0; i<blockno; i++) {
2686 if (dic->seq >= ebpp[i]->fSeq && dic->seq <= ebpp[i]->lSeq) {
2691 wassert (i!=blockno); // no way to recover from here
2694 if (IS_SYMOP(IC_RIGHT(dic))) {
2695 /* make sure the right side does not have any definitions
2697 dbv = OP_DEFS(IC_RIGHT(dic));
2698 for (lic = ic; lic && lic != dic ; lic = lic->prev) {
2699 if (bitVectBitValue(dbv,lic->key))
2702 /* make sure they have the same type */
2703 if (IS_SPEC(operandType(IC_LEFT(ic))))
2705 sym_link *itype=operandType(IC_LEFT(ic));
2706 sym_link *ditype=operandType(IC_RIGHT(dic));
2708 if (SPEC_USIGN(itype)!=SPEC_USIGN(ditype) ||
2709 SPEC_LONG(itype)!=SPEC_LONG(ditype))
2712 /* extend the live range of replaced operand if needed */
2713 if (OP_SYMBOL(IC_RIGHT(dic))->liveTo < ic->seq) {
2714 OP_SYMBOL(IC_RIGHT(dic))->liveTo = ic->seq;
2716 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2719 /* we now we know that it has one & only one def & use
2720 and the that the definition is an assignment */
2721 ReplaceOpWithCheaperOp(&IC_LEFT (ic), IC_RIGHT (dic));
2722 remiCodeFromeBBlock (ebp, dic);
2723 hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
2726 /*-----------------------------------------------------------------*/
2727 /* packRegisters - does some transformations to reduce register */
2729 /*-----------------------------------------------------------------*/
2731 packRegisters (eBBlock ** ebpp, int blockno)
2735 eBBlock *ebp=ebpp[blockno];
2742 /* look for assignments of the form */
2743 /* iTempNN = TRueSym (someoperation) SomeOperand */
2745 /* TrueSym := iTempNN:1 */
2746 for (ic = ebp->sch; ic; ic = ic->next)
2748 /* find assignment of the form TrueSym := iTempNN:1 */
2749 if (ic->op == '=' && !POINTER_SET (ic) )
2750 change += packRegsForAssign (ic, ebp);
2757 for (ic = ebp->sch; ic; ic = ic->next)
2759 //packRegsForLiteral (ic);
2761 /* if this is an itemp & result of an address of a true sym
2762 then mark this as rematerialisable */
2763 if (ic->op == ADDRESS_OF &&
2764 IS_ITEMP (IC_RESULT (ic)) &&
2765 IS_TRUE_SYMOP (IC_LEFT (ic)) &&
2766 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1 &&
2767 !OP_SYMBOL (IC_LEFT (ic))->onStack )
2770 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2771 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2772 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2776 if (ic->op == '=' &&
2777 !POINTER_SET (ic) &&
2778 IS_ITEMP (IC_RESULT (ic)) &&
2779 IS_VALOP (IC_RIGHT (ic)) &&
2780 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1)
2783 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2784 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2785 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2789 /* if straight assignment then carry remat flag if
2790 this is the only definition */
2791 if (ic->op == '=' &&
2792 !POINTER_SET (ic) &&
2793 IS_SYMOP (IC_RIGHT (ic)) &&
2794 OP_SYMBOL (IC_RIGHT (ic))->remat &&
2795 !IS_CAST_ICODE(OP_SYMBOL (IC_RIGHT (ic))->rematiCode) &&
2796 bitVectnBitsOn (OP_SYMBOL (IC_RESULT (ic))->defs) <= 1)
2799 OP_SYMBOL (IC_RESULT (ic))->remat =
2800 OP_SYMBOL (IC_RIGHT (ic))->remat;
2801 OP_SYMBOL (IC_RESULT (ic))->rematiCode =
2802 OP_SYMBOL (IC_RIGHT (ic))->rematiCode;
2805 /* if cast to a generic pointer & the pointer being
2806 cast is remat, then we can remat this cast as well */
2807 if (ic->op == CAST &&
2808 IS_SYMOP(IC_RIGHT(ic)) &&
2809 OP_SYMBOL(IC_RIGHT(ic))->remat &&
2810 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1) {
2811 sym_link *to_type = operandType(IC_LEFT(ic));
2812 sym_link *from_type = operandType(IC_RIGHT(ic));
2813 if (IS_GENPTR(to_type) && IS_PTR(from_type)) {
2814 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2815 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2816 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2820 /* if this is a +/- operation with a rematerizable
2821 then mark this as rematerializable as well */
2822 if ((ic->op == '+' || ic->op == '-') &&
2823 (IS_SYMOP (IC_LEFT (ic)) &&
2824 IS_ITEMP (IC_RESULT (ic)) &&
2825 IS_OP_LITERAL (IC_RIGHT (ic))) &&
2826 OP_SYMBOL (IC_LEFT (ic))->remat &&
2827 (!IS_SYMOP (IC_RIGHT (ic)) || !IS_CAST_ICODE(OP_SYMBOL (IC_RIGHT (ic))->rematiCode)) &&
2828 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1)
2830 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2831 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2832 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2835 /* mark the pointer usages */
2836 if (POINTER_SET (ic))
2837 OP_SYMBOL (IC_RESULT (ic))->uptr = 1;
2839 if (POINTER_GET (ic) &&
2840 IS_SYMOP(IC_LEFT (ic)))
2841 OP_SYMBOL (IC_LEFT (ic))->uptr = 1;
2846 /* if we are using a symbol on the stack
2847 then we should say hc08_ptrRegReq */
2848 if (ic->op == IFX && IS_SYMOP (IC_COND (ic)))
2849 hc08_ptrRegReq += ((OP_SYMBOL (IC_COND (ic))->onStack ||
2850 OP_SYMBOL (IC_COND (ic))->iaccess) ? 1 : 0);
2851 else if (ic->op == JUMPTABLE && IS_SYMOP (IC_JTCOND (ic)))
2852 hc08_ptrRegReq += ((OP_SYMBOL (IC_JTCOND (ic))->onStack ||
2853 OP_SYMBOL (IC_JTCOND (ic))->iaccess) ? 1 : 0);
2856 if (IS_SYMOP (IC_LEFT (ic)))
2857 hc08_ptrRegReq += ((OP_SYMBOL (IC_LEFT (ic))->onStack ||
2858 OP_SYMBOL (IC_LEFT (ic))->iaccess) ? 1 : 0);
2859 if (IS_SYMOP (IC_RIGHT (ic)))
2860 hc08_ptrRegReq += ((OP_SYMBOL (IC_RIGHT (ic))->onStack ||
2861 OP_SYMBOL (IC_RIGHT (ic))->iaccess) ? 1 : 0);
2862 if (IS_SYMOP (IC_RESULT (ic)))
2863 hc08_ptrRegReq += ((OP_SYMBOL (IC_RESULT (ic))->onStack ||
2864 OP_SYMBOL (IC_RESULT (ic))->iaccess) ? 1 : 0);
2869 /* if the condition of an if instruction
2870 is defined in the previous instruction and
2871 this is the only usage then
2872 mark the itemp as a conditional */
2873 if ((IS_CONDITIONAL (ic) ||
2874 (IS_BITWISE_OP(ic) && isBitwiseOptimizable (ic))) &&
2875 ic->next && ic->next->op == IFX &&
2876 bitVectnBitsOn (OP_USES(IC_RESULT(ic)))==1 &&
2877 isOperandEqual (IC_RESULT (ic), IC_COND (ic->next)) &&
2878 OP_SYMBOL (IC_RESULT (ic))->liveTo <= ic->next->seq)
2880 OP_SYMBOL (IC_RESULT (ic))->regType = REG_CND;
2884 /* reduce for support function calls */
2885 if (ic->supportRtn || (ic->op != IFX && ic->op != JUMPTABLE))
2886 packRegsForSupport (ic, ebp);
2889 /* some cases the redundant moves can
2890 can be eliminated for return statements */
2891 if ((ic->op == RETURN || (ic->op == SEND && ic->argreg == 1)) &&
2892 /* !isOperandInFarSpace (IC_LEFT (ic)) && */
2893 options.model == MODEL_SMALL) {
2894 packRegsForOneuse (ic, IC_LEFT (ic), ebp);
2897 /* if pointer set & left has a size more than
2898 one and right is not in far space */
2899 if (POINTER_SET (ic) &&
2900 /* !isOperandInFarSpace (IC_RIGHT (ic)) && */
2901 !OP_SYMBOL (IC_RESULT (ic))->remat &&
2902 !IS_OP_RUONLY (IC_RIGHT (ic))
2903 /* && getSize (aggrToPtr (operandType (IC_RESULT (ic)), FALSE)) > 1 */ )
2904 packRegsForOneuse (ic, IC_RESULT (ic), ebp);
2906 /* if pointer get */
2907 if (POINTER_GET (ic) &&
2908 IS_SYMOP (IC_LEFT (ic)) &&
2909 /* !isOperandInFarSpace (IC_RESULT (ic)) && */
2910 !OP_SYMBOL (IC_LEFT (ic))->remat &&
2911 !IS_OP_RUONLY (IC_RESULT (ic))
2912 /* && getSize (aggrToPtr (operandType (IC_LEFT (ic)), FALSE)) > 1 */)
2913 packRegsForOneuse (ic, IC_LEFT (ic), ebp);
2916 /* if this is cast for intergral promotion then
2917 check if only use of the definition of the
2918 operand being casted/ if yes then replace
2919 the result of that arithmetic operation with
2920 this result and get rid of the cast */
2923 sym_link *fromType = operandType (IC_RIGHT (ic));
2924 sym_link *toType = operandType (IC_LEFT (ic));
2926 if (IS_INTEGRAL (fromType) && IS_INTEGRAL (toType) &&
2927 getSize (fromType) != getSize (toType) &&
2928 SPEC_USIGN (fromType) == SPEC_USIGN (toType))
2931 iCode *dic = packRegsForOneuse (ic, IC_RIGHT (ic), ebp);
2934 if (IS_ARITHMETIC_OP (dic))
2936 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2937 ReplaceOpWithCheaperOp(&IC_RESULT (dic), IC_RESULT (ic));
2938 remiCodeFromeBBlock (ebp, ic);
2939 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
2940 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
2941 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
2945 OP_SYMBOL (IC_RIGHT (ic))->ruonly = 0;
2951 /* if the type from and type to are the same
2952 then if this is the only use then packit */
2953 if (compareType (operandType (IC_RIGHT (ic)),
2954 operandType (IC_LEFT (ic))) == 1)
2956 iCode *dic = packRegsForOneuse (ic, IC_RIGHT (ic), ebp);
2959 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2960 ReplaceOpWithCheaperOp(&IC_RESULT (dic), IC_RESULT (ic));
2961 remiCodeFromeBBlock (ebp, ic);
2962 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
2963 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
2964 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
2973 iTempNN := (some variable in farspace) V1
2978 if (ic->op == IPUSH)
2980 packForPush (ic, ebpp, blockno);
2985 /* pack registers for accumulator use, when the
2986 result of an arithmetic or bit wise operation
2987 has only one use, that use is immediately following
2988 the defintion and the using iCode has only one
2989 operand or has two operands but one is literal &
2990 the result of that operation is not on stack then
2991 we can leave the result of this operation in x:a
2993 if ((IS_ARITHMETIC_OP (ic)
2994 || IS_CONDITIONAL(ic)
2995 || IS_BITWISE_OP (ic)
2999 || ic->op == GETHBIT
3000 || ic->op == LEFT_OP || ic->op == RIGHT_OP || ic->op == CALL
3001 || (ic->op == ADDRESS_OF && isOperandOnStack (IC_LEFT (ic)))
3002 || ic->op == RECEIVE
3004 IS_ITEMP (IC_RESULT (ic)) &&
3005 getSize (operandType (IC_RESULT (ic))) <= 1)
3007 packRegsForAccUse (ic);
3012 /*-----------------------------------------------------------------*/
3013 /* assignRegisters - assigns registers to each live range as need */
3014 /*-----------------------------------------------------------------*/
3016 hc08_assignRegisters (eBBlock ** ebbs, int count)
3021 setToNull ((void *) &_G.funcrUsed);
3022 setToNull ((void *) &_G.regAssigned);
3023 setToNull ((void *) &_G.totRegAssigned);
3024 hc08_ptrRegReq = _G.stackExtend = _G.dataExtend = 0;
3026 hc08_reg_a = hc08_regWithIdx(A_IDX);
3027 hc08_reg_x = hc08_regWithIdx(X_IDX);
3028 hc08_reg_h = hc08_regWithIdx(H_IDX);
3029 hc08_reg_hx = hc08_regWithIdx(HX_IDX);
3030 hc08_reg_xa = hc08_regWithIdx(XA_IDX);
3031 hc08_reg_sp = hc08_regWithIdx(SP_IDX);
3034 /* change assignments this will remove some
3035 live ranges reducing some register pressure */
3036 for (i = 0; i < count; i++)
3037 packRegisters (ebbs, i);
3039 /* liveranges probably changed by register packing
3040 so we compute them again */
3041 recomputeLiveRanges (ebbs, count);
3043 if (options.dump_pack)
3044 dumpEbbsToFileExt (DUMP_PACK, ebbs, count);
3046 /* first determine for each live range the number of
3047 registers & the type of registers required for each */
3050 /* and serially allocate registers */
3051 serialRegAssign (ebbs, count);
3054 //setToNull ((void *) &_G.regAssigned);
3055 //setToNull ((void *) &_G.totRegAssigned);
3058 /* if stack was extended then tell the user */
3061 /* werror(W_TOOMANY_SPILS,"stack", */
3062 /* _G.stackExtend,currFunc->name,""); */
3068 /* werror(W_TOOMANY_SPILS,"data space", */
3069 /* _G.dataExtend,currFunc->name,""); */
3073 /* after that create the register mask
3074 for each of the instruction */
3075 createRegMask (ebbs, count);
3077 /* redo that offsets for stacked automatic variables */
3079 redoStackOffsets ();
3082 if (options.dump_rassgn)
3084 dumpEbbsToFileExt (DUMP_RASSGN, ebbs, count);
3085 dumpLiveRanges (DUMP_LRANGE, liveRanges);
3088 /* do the overlaysegment stuff SDCCmem.c */
3089 doOverlays (ebbs, count);
3091 /* now get back the chain */
3092 ic = iCodeLabelOptimize (iCodeFromeBBlock (ebbs, count));
3096 /* free up any _G.stackSpil locations allocated */
3097 applyToSet (_G.stackSpil, deallocStackSpil);
3099 setToNull ((void **) &_G.stackSpil);
3100 setToNull ((void **) &_G.spiltSet);
3101 /* mark all registers as free */