1 /*------------------------------------------------------------------------
3 SDCCralloc.c - source file for register allocation. (8051) specific
5 Written By - Sandeep Dutta . sandeep.dutta@usa.net (1998)
7 This program is free software; you can redistribute it and/or modify it
8 under the terms of the GNU General Public License as published by the
9 Free Software Foundation; either version 2, or (at your option) any
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
21 In other words, you are welcome to use, share and improve this program.
22 You are forbidden to forbid anyone else to use, share and improve
23 what you give them. Help stamp out software-hoarding!
24 -------------------------------------------------------------------------*/
30 /*-----------------------------------------------------------------*/
31 /* At this point we start getting processor specific although */
32 /* some routines are non-processor specific & can be reused when */
33 /* targetting other processors. The decision for this will have */
34 /* to be made on a routine by routine basis */
35 /* routines used to pack registers are most definitely not reusable */
36 /* since the pack the registers depending strictly on the MCU */
37 /*-----------------------------------------------------------------*/
47 bitVect *totRegAssigned; /* final set of LRs that got into registers */
50 bitVect *funcrUsed; /* registers used in a function */
56 /* Shared with gen.c */
57 int ds390_ptrRegReq; /* one byte pointer register required */
63 {REG_GPR, R2_IDX, REG_GPR, "r2", "ar2", "0", 2, 1, 1},
64 {REG_GPR, R3_IDX, REG_GPR, "r3", "ar3", "0", 3, 1, 1},
65 {REG_GPR, R4_IDX, REG_GPR, "r4", "ar4", "0", 4, 1, 1},
66 {REG_GPR, R5_IDX, REG_GPR, "r5", "ar5", "0", 5, 1, 1},
67 {REG_GPR, R6_IDX, REG_GPR, "r6", "ar6", "0", 6, 1, 1},
68 {REG_GPR, R7_IDX, REG_GPR, "r7", "ar7", "0", 7, 1, 1},
69 {REG_PTR, R0_IDX, REG_PTR, "r0", "ar0", "0", 0, 1, 1},
70 {REG_PTR, R1_IDX, REG_PTR, "r1", "ar1", "0", 1, 1, 1},
71 {REG_GPR, DPL_IDX, REG_GPR, "dpl", "dpl", "dpl", 0, 0, 0},
72 {REG_GPR, DPH_IDX, REG_GPR, "dph", "dph", "dph", 0, 0, 0},
73 {REG_GPR, DPX_IDX, REG_GPR, "dpx", "dpx", "dpx", 0, 0, 0},
74 {REG_GPR, B_IDX, REG_GPR, "b", "b", "b", 0, 0, 0},
75 {REG_GPR, X8_IDX, REG_GPR, "x8", "x8", "xreg", 0, 0, 0},
76 {REG_GPR, X9_IDX, REG_GPR, "x9", "x9", "xreg", 1, 0, 0},
77 {REG_GPR, X10_IDX, REG_GPR, "x10", "x10", "xreg", 2, 0, 0},
78 {REG_GPR, X11_IDX, REG_GPR, "x11", "x11", "xreg", 3, 0, 0},
79 {REG_GPR, X12_IDX, REG_GPR, "x12", "x12", "xreg", 4, 0, 0},
80 {REG_CND, CND_IDX, REG_GPR, "C", "C", "xreg", 0, 0, 0},
83 static void spillThis (symbol *);
84 static void freeAllRegs ();
85 static iCode * packRegsDPTRuse (operand *);
86 static int packRegsDPTRnuse (operand *,int);
88 /*-----------------------------------------------------------------*/
89 /* allocReg - allocates register of given type */
90 /*-----------------------------------------------------------------*/
96 for (i = 0; i < ds390_nRegs; i++)
99 /* if type is given as 0 then any
100 free register will do */
104 regs390[i].isFree = 0;
107 bitVectSetBit (currFunc->regsUsed, i);
110 /* other wise look for specific type
112 if (regs390[i].isFree &&
113 regs390[i].type == type)
115 regs390[i].isFree = 0;
118 bitVectSetBit (currFunc->regsUsed, i);
125 /*-----------------------------------------------------------------*/
126 /* ds390_regWithIdx - returns pointer to register wit index number */
127 /*-----------------------------------------------------------------*/
129 ds390_regWithIdx (int idx)
133 for (i = 0; i < ds390_nRegs; i++)
134 if (regs390[i].rIdx == idx)
137 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
138 "regWithIdx not found");
142 /*-----------------------------------------------------------------*/
143 /* freeReg - frees a register */
144 /*-----------------------------------------------------------------*/
151 /*-----------------------------------------------------------------*/
152 /* useReg - marks a register as used */
153 /*-----------------------------------------------------------------*/
161 /*-----------------------------------------------------------------*/
162 /* nFreeRegs - returns number of free registers */
163 /*-----------------------------------------------------------------*/
170 for (i = 0; i < ds390_nRegs; i++)
171 if (regs390[i].isFree && regs390[i].type == type)
176 /*-----------------------------------------------------------------*/
177 /* nfreeRegsType - free registers with type */
178 /*-----------------------------------------------------------------*/
180 nfreeRegsType (int type)
185 if ((nfr = nFreeRegs (type)) == 0)
186 return nFreeRegs (REG_GPR);
189 return nFreeRegs (type);
194 /*-----------------------------------------------------------------*/
195 /* isOperandInReg - returns true if operand is currently in regs */
196 /*-----------------------------------------------------------------*/
197 static int isOperandInReg(operand *op)
199 if (!IS_SYMOP(op)) return 0;
200 if (OP_SYMBOL(op)->ruonly) return 1;
201 if (OP_SYMBOL(op)->accuse) return 1;
202 if (OP_SYMBOL(op)->dptr) return 1;
203 return bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(op)->key);
206 /*-----------------------------------------------------------------*/
207 /* computeSpillable - given a point find the spillable live ranges */
208 /*-----------------------------------------------------------------*/
210 computeSpillable (iCode * ic)
214 /* spillable live ranges are those that are live at this
215 point . the following categories need to be subtracted
217 a) - those that are already spilt
218 b) - if being used by this one
219 c) - defined by this one */
221 spillable = bitVectCopy (ic->rlive);
223 bitVectCplAnd (spillable, _G.spiltSet); /* those already spilt */
225 bitVectCplAnd (spillable, ic->uses); /* used in this one */
226 bitVectUnSetBit (spillable, ic->defKey);
227 spillable = bitVectIntersect (spillable, _G.regAssigned);
232 /*-----------------------------------------------------------------*/
233 /* noSpilLoc - return true if a variable has no spil location */
234 /*-----------------------------------------------------------------*/
236 noSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
238 return (sym->usl.spillLoc ? 0 : 1);
241 /*-----------------------------------------------------------------*/
242 /* hasSpilLoc - will return 1 if the symbol has spil location */
243 /*-----------------------------------------------------------------*/
245 hasSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
247 return (sym->usl.spillLoc ? 1 : 0);
250 /*-----------------------------------------------------------------*/
251 /* directSpilLoc - will return 1 if the splilocation is in direct */
252 /*-----------------------------------------------------------------*/
254 directSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
256 if (sym->usl.spillLoc &&
257 (IN_DIRSPACE (SPEC_OCLS (sym->usl.spillLoc->etype))))
263 /*-----------------------------------------------------------------*/
264 /* hasSpilLocnoUptr - will return 1 if the symbol has spil location */
265 /* but is not used as a pointer */
266 /*-----------------------------------------------------------------*/
268 hasSpilLocnoUptr (symbol * sym, eBBlock * ebp, iCode * ic)
270 return ((sym->usl.spillLoc && !sym->uptr) ? 1 : 0);
273 /*-----------------------------------------------------------------*/
274 /* rematable - will return 1 if the remat flag is set */
275 /*-----------------------------------------------------------------*/
277 rematable (symbol * sym, eBBlock * ebp, iCode * ic)
282 /*-----------------------------------------------------------------*/
283 /* notUsedInRemaining - not used or defined in remain of the block */
284 /*-----------------------------------------------------------------*/
286 notUsedInRemaining (symbol * sym, eBBlock * ebp, iCode * ic)
288 return ((usedInRemaining (operandFromSymbol (sym), ic) ? 0 : 1) &&
289 allDefsOutOfRange (sym->defs, ebp->fSeq, ebp->lSeq));
292 /*-----------------------------------------------------------------*/
293 /* allLRs - return true for all */
294 /*-----------------------------------------------------------------*/
296 allLRs (symbol * sym, eBBlock * ebp, iCode * ic)
301 /*-----------------------------------------------------------------*/
302 /* liveRangesWith - applies function to a given set of live range */
303 /*-----------------------------------------------------------------*/
305 liveRangesWith (bitVect * lrs, int (func) (symbol *, eBBlock *, iCode *),
306 eBBlock * ebp, iCode * ic)
311 if (!lrs || !lrs->size)
314 for (i = 1; i < lrs->size; i++)
317 if (!bitVectBitValue (lrs, i))
320 /* if we don't find it in the live range
321 hash table we are in serious trouble */
322 if (!(sym = hTabItemWithKey (liveRanges, i)))
324 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
325 "liveRangesWith could not find liveRange");
329 if (func (sym, ebp, ic) && bitVectBitValue (_G.regAssigned, sym->key))
330 addSetHead (&rset, sym);
337 /*-----------------------------------------------------------------*/
338 /* leastUsedLR - given a set determines which is the least used */
339 /*-----------------------------------------------------------------*/
341 leastUsedLR (set * sset)
343 symbol *sym = NULL, *lsym = NULL;
345 sym = lsym = setFirstItem (sset);
350 for (; lsym; lsym = setNextItem (sset))
353 /* if usage is the same then prefer
354 the spill the smaller of the two */
355 if (lsym->used == sym->used)
356 if (getSize (lsym->type) < getSize (sym->type))
360 if (lsym->used < sym->used)
365 setToNull ((void **) &sset);
370 /*-----------------------------------------------------------------*/
371 /* noOverLap - will iterate through the list looking for over lap */
372 /*-----------------------------------------------------------------*/
374 noOverLap (set * itmpStack, symbol * fsym)
378 for (sym = setFirstItem (itmpStack); sym;
379 sym = setNextItem (itmpStack))
381 if (bitVectBitValue(sym->clashes,fsym->key)) return 0;
386 /*-----------------------------------------------------------------*/
387 /* isFree - will return 1 if the a free spil location is found */
388 /*-----------------------------------------------------------------*/
393 V_ARG (symbol **, sloc);
394 V_ARG (symbol *, fsym);
396 /* if already found */
400 /* if it is free && and the itmp assigned to
401 this does not have any overlapping live ranges
402 with the one currently being assigned and
403 the size can be accomodated */
405 noOverLap (sym->usl.itmpStack, fsym) &&
406 getSize (sym->type) >= getSize (fsym->type))
415 /*-----------------------------------------------------------------*/
416 /* spillLRWithPtrReg :- will spil those live ranges which use PTR */
417 /*-----------------------------------------------------------------*/
419 spillLRWithPtrReg (symbol * forSym)
425 if (!_G.regAssigned ||
426 bitVectIsZero (_G.regAssigned))
429 r0 = ds390_regWithIdx (R0_IDX);
430 r1 = ds390_regWithIdx (R1_IDX);
432 /* for all live ranges */
433 for (lrsym = hTabFirstItem (liveRanges, &k); lrsym;
434 lrsym = hTabNextItem (liveRanges, &k))
438 /* if no registers assigned to it or
440 /* if it does not overlap with this then
441 not need to spill it */
443 if (lrsym->isspilt || !lrsym->nRegs ||
444 (lrsym->liveTo < forSym->liveFrom))
447 /* go thru the registers : if it is either
448 r0 or r1 then spil it */
449 for (j = 0; j < lrsym->nRegs; j++)
450 if (lrsym->regs[j] == r0 ||
451 lrsym->regs[j] == r1)
460 /*-----------------------------------------------------------------*/
461 /* createStackSpil - create a location on the stack to spil */
462 /*-----------------------------------------------------------------*/
464 createStackSpil (symbol * sym)
467 int useXstack, model, noOverlay;
471 /* first go try and find a free one that is already
472 existing on the stack */
473 if (applyToSet (_G.stackSpil, isFree, &sloc, sym))
475 /* found a free one : just update & return */
476 sym->usl.spillLoc = sloc;
479 addSetHead (&sloc->usl.itmpStack, sym);
483 /* could not then have to create one , this is the hard part
484 we need to allocate this on the stack : this is really a
485 hack!! but cannot think of anything better at this time */
487 if (SNPRINTF (slocBuffer, sizeof(slocBuffer),
488 "sloc%d", _G.slocNum++) >= sizeof (slocBuffer))
490 fprintf (stderr, "***Internal error: slocBuffer overflowed: %s:%d\n",
495 sloc = newiTemp (slocBuffer);
497 /* set the type to the spilling symbol */
498 sloc->type = copyLinkChain (sym->type);
499 sloc->etype = getSpec (sloc->type);
500 if (options.model == MODEL_SMALL) {
501 SPEC_SCLS (sloc->etype) = S_DATA;
503 SPEC_SCLS (sloc->etype) = S_XDATA;
505 SPEC_EXTR (sloc->etype) = 0;
506 SPEC_STAT (sloc->etype) = 0;
507 SPEC_VOLATILE(sloc->etype) = 0;
508 SPEC_ABSA(sloc->etype) = 0;
510 /* we don't allow it to be allocated`
511 onto the external stack since : so we
512 temporarily turn it off ; we also
513 turn off memory model to prevent
514 the spil from going to the external storage
515 and turn off overlaying
518 useXstack = options.useXstack;
519 model = options.model;
520 noOverlay = options.noOverlay;
521 options.noOverlay = 1;
523 /* options.model = options.useXstack = 0; */
527 options.useXstack = useXstack;
528 options.model = model;
529 options.noOverlay = noOverlay;
530 sloc->isref = 1; /* to prevent compiler warning */
532 /* if it is on the stack then update the stack */
533 if (IN_STACK (sloc->etype))
535 currFunc->stack += getSize (sloc->type);
536 _G.stackExtend += getSize (sloc->type);
539 _G.dataExtend += getSize (sloc->type);
541 /* add it to the _G.stackSpil set */
542 addSetHead (&_G.stackSpil, sloc);
543 sym->usl.spillLoc = sloc;
546 /* add it to the set of itempStack set
547 of the spill location */
548 addSetHead (&sloc->usl.itmpStack, sym);
552 /*-----------------------------------------------------------------*/
553 /* isSpiltOnStack - returns true if the spil location is on stack */
554 /*-----------------------------------------------------------------*/
556 isSpiltOnStack (symbol * sym)
566 /* if (sym->_G.stackSpil) */
569 if (!sym->usl.spillLoc)
572 etype = getSpec (sym->usl.spillLoc->type);
573 if (IN_STACK (etype))
579 /*-----------------------------------------------------------------*/
580 /* spillThis - spils a specific operand */
581 /*-----------------------------------------------------------------*/
583 spillThis (symbol * sym)
586 /* if this is rematerializable or has a spillLocation
587 we are okay, else we need to create a spillLocation
589 if (!(sym->remat || sym->usl.spillLoc))
590 createStackSpil (sym);
593 /* mark it has spilt & put it in the spilt set */
594 sym->isspilt = sym->spillA = 1;
595 _G.spiltSet = bitVectSetBit (_G.spiltSet, sym->key);
597 bitVectUnSetBit (_G.regAssigned, sym->key);
598 bitVectUnSetBit (_G.totRegAssigned, sym->key);
600 for (i = 0; i < sym->nRegs; i++)
604 freeReg (sym->regs[i]);
608 /* if spilt on stack then free up r0 & r1
609 if they could have been assigned to some
611 if (!ds390_ptrRegReq && isSpiltOnStack (sym))
613 ds390_ptrRegReq += !options.stack10bit;
614 spillLRWithPtrReg (sym);
617 if (sym->usl.spillLoc && !sym->remat)
618 sym->usl.spillLoc->allocreq++;
622 /*-----------------------------------------------------------------*/
623 /* selectSpil - select a iTemp to spil : rather a simple procedure */
624 /*-----------------------------------------------------------------*/
626 selectSpil (iCode * ic, eBBlock * ebp, symbol * forSym)
628 bitVect *lrcs = NULL;
632 /* get the spillable live ranges */
633 lrcs = computeSpillable (ic);
635 /* get all live ranges that are rematerizable */
636 if ((selectS = liveRangesWith (lrcs, rematable, ebp, ic)))
639 /* return the least used of these */
640 return leastUsedLR (selectS);
643 /* get live ranges with spillLocations in direct space */
644 if ((selectS = liveRangesWith (lrcs, directSpilLoc, ebp, ic)))
646 sym = leastUsedLR (selectS);
647 strncpyz (sym->rname,
648 sym->usl.spillLoc->rname[0] ?
649 sym->usl.spillLoc->rname : sym->usl.spillLoc->name,
652 /* mark it as allocation required */
653 sym->usl.spillLoc->allocreq++;
657 /* if the symbol is local to the block then */
658 if (forSym->liveTo < ebp->lSeq)
661 /* check if there are any live ranges allocated
662 to registers that are not used in this block */
663 if (!_G.blockSpil && (selectS = liveRangesWith (lrcs, notUsedInBlock, ebp, ic)))
665 sym = leastUsedLR (selectS);
666 /* if this is not rematerializable */
675 /* check if there are any live ranges that not
676 used in the remainder of the block */
677 if (!_G.blockSpil && (selectS = liveRangesWith (lrcs, notUsedInRemaining, ebp, ic)))
679 sym = leastUsedLR (selectS);
692 /* find live ranges with spillocation && not used as pointers */
693 if ((selectS = liveRangesWith (lrcs, hasSpilLocnoUptr, ebp, ic)))
696 sym = leastUsedLR (selectS);
697 /* mark this as allocation required */
698 sym->usl.spillLoc->allocreq++;
702 /* find live ranges with spillocation */
703 if ((selectS = liveRangesWith (lrcs, hasSpilLoc, ebp, ic)))
706 sym = leastUsedLR (selectS);
707 sym->usl.spillLoc->allocreq++;
711 /* couldn't find then we need to create a spil
712 location on the stack , for which one? the least
714 if ((selectS = liveRangesWith (lrcs, noSpilLoc, ebp, ic)))
717 /* return a created spil location */
718 sym = createStackSpil (leastUsedLR (selectS));
719 sym->usl.spillLoc->allocreq++;
723 /* this is an extreme situation we will spill
724 this one : happens very rarely but it does happen */
730 /*-----------------------------------------------------------------*/
731 /* spilSomething - spil some variable & mark registers as free */
732 /*-----------------------------------------------------------------*/
734 spilSomething (iCode * ic, eBBlock * ebp, symbol * forSym)
739 /* get something we can spil */
740 ssym = selectSpil (ic, ebp, forSym);
742 /* mark it as spilt */
743 ssym->isspilt = ssym->spillA = 1;
744 _G.spiltSet = bitVectSetBit (_G.spiltSet, ssym->key);
746 /* mark it as not register assigned &
747 take it away from the set */
748 bitVectUnSetBit (_G.regAssigned, ssym->key);
749 bitVectUnSetBit (_G.totRegAssigned, ssym->key);
751 /* mark the registers as free */
752 for (i = 0; i < ssym->nRegs; i++)
754 freeReg (ssym->regs[i]);
756 /* if spilt on stack then free up r0 & r1
757 if they could have been assigned to as gprs */
758 if (!ds390_ptrRegReq && isSpiltOnStack (ssym) && !options.stack10bit)
761 spillLRWithPtrReg (ssym);
764 /* if this was a block level spil then insert push & pop
765 at the start & end of block respectively */
768 iCode *nic = newiCode (IPUSH, operandFromSymbol (ssym), NULL);
769 /* add push to the start of the block */
770 addiCodeToeBBlock (ebp, nic, (ebp->sch->op == LABEL ?
771 ebp->sch->next : ebp->sch));
772 nic = newiCode (IPOP, operandFromSymbol (ssym), NULL);
773 /* add pop to the end of the block */
774 addiCodeToeBBlock (ebp, nic, NULL);
777 /* if spilt because not used in the remainder of the
778 block then add a push before this instruction and
779 a pop at the end of the block */
780 if (ssym->remainSpil)
783 iCode *nic = newiCode (IPUSH, operandFromSymbol (ssym), NULL);
784 /* add push just before this instruction */
785 addiCodeToeBBlock (ebp, nic, ic);
787 nic = newiCode (IPOP, operandFromSymbol (ssym), NULL);
788 /* add pop to the end of the block */
789 addiCodeToeBBlock (ebp, nic, NULL);
798 /*-----------------------------------------------------------------*/
799 /* getRegPtr - will try for PTR if not a GPR type if not spil */
800 /*-----------------------------------------------------------------*/
802 getRegPtr (iCode * ic, eBBlock * ebp, symbol * sym)
807 /* try for a ptr type */
808 if ((reg = allocReg (REG_PTR)))
811 /* try for gpr type */
812 if ((reg = allocReg (REG_GPR)))
815 /* we have to spil */
816 if (!spilSomething (ic, ebp, sym))
819 /* this looks like an infinite loop but
820 in really selectSpil will abort */
824 /*-----------------------------------------------------------------*/
825 /* getRegGpr - will try for GPR if not spil */
826 /*-----------------------------------------------------------------*/
828 getRegGpr (iCode * ic, eBBlock * ebp, symbol * sym)
833 /* try for gpr type */
834 if ((reg = allocReg (REG_GPR)))
837 if (!ds390_ptrRegReq)
838 if ((reg = allocReg (REG_PTR)))
841 /* we have to spil */
842 if (!spilSomething (ic, ebp, sym))
845 /* this looks like an infinite loop but
846 in really selectSpil will abort */
850 /*-----------------------------------------------------------------*/
851 /* getRegPtrNoSpil - get it cannot split */
852 /*-----------------------------------------------------------------*/
853 static regs *getRegPtrNoSpil()
857 /* try for a ptr type */
858 if ((reg = allocReg (REG_PTR)))
861 /* try for gpr type */
862 if ((reg = allocReg (REG_GPR)))
867 /* just to make the compiler happy */
871 /*-----------------------------------------------------------------*/
872 /* getRegGprNoSpil - get it cannot split */
873 /*-----------------------------------------------------------------*/
874 static regs *getRegGprNoSpil()
878 if ((reg = allocReg (REG_GPR)))
881 if (!ds390_ptrRegReq)
882 if ((reg = allocReg (REG_PTR)))
887 /* just to make the compiler happy */
891 /*-----------------------------------------------------------------*/
892 /* symHasReg - symbol has a given register */
893 /*-----------------------------------------------------------------*/
895 symHasReg (symbol * sym, regs * reg)
899 for (i = 0; i < sym->nRegs; i++)
900 if (sym->regs[i] == reg)
906 /*-----------------------------------------------------------------*/
907 /* deassignLRs - check the live to and if they have registers & are */
908 /* not spilt then free up the registers */
909 /*-----------------------------------------------------------------*/
911 deassignLRs (iCode * ic, eBBlock * ebp)
917 for (sym = hTabFirstItem (liveRanges, &k); sym;
918 sym = hTabNextItem (liveRanges, &k))
922 /* if it does not end here */
923 if (sym->liveTo > ic->seq)
926 /* if it was spilt on stack then we can
927 mark the stack spil location as free */
932 sym->usl.spillLoc->isFree = 1;
938 if (!bitVectBitValue (_G.regAssigned, sym->key))
941 /* special case check if this is an IFX &
942 the privious one was a pop and the
943 previous one was not spilt then keep track
945 if (ic->op == IFX && ic->prev &&
946 ic->prev->op == IPOP &&
947 !ic->prev->parmPush &&
948 !OP_SYMBOL (IC_LEFT (ic->prev))->isspilt)
949 psym = OP_SYMBOL (IC_LEFT (ic->prev));
955 bitVectUnSetBit (_G.regAssigned, sym->key);
957 /* if the result of this one needs registers
958 and does not have it then assign it right
960 if (IC_RESULT (ic) &&
961 !(SKIP_IC2 (ic) || /* not a special icode */
962 ic->op == JUMPTABLE ||
968 (result = OP_SYMBOL (IC_RESULT (ic))) && /* has a result */
969 result->liveTo > ic->seq && /* and will live beyond this */
970 result->liveTo <= ebp->lSeq && /* does not go beyond this block */
971 result->regType == sym->regType && /* same register types */
972 result->nRegs && /* which needs registers */
973 !result->isspilt && /* and does not already have them */
975 !bitVectBitValue (_G.regAssigned, result->key) &&
976 /* the number of free regs + number of regs in this LR
977 can accomodate the what result Needs */
978 ((nfreeRegsType (result->regType) +
979 sym->nRegs) >= result->nRegs)
983 for (i = 0; i < result->nRegs; i++)
985 result->regs[i] = sym->regs[i];
987 result->regs[i] = getRegGpr (ic, ebp, result);
989 _G.regAssigned = bitVectSetBit (_G.regAssigned, result->key);
990 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, result->key);
994 /* free the remaining */
995 for (; i < sym->nRegs; i++)
999 if (!symHasReg (psym, sym->regs[i]))
1000 freeReg (sym->regs[i]);
1003 freeReg (sym->regs[i]);
1010 /*-----------------------------------------------------------------*/
1011 /* reassignLR - reassign this to registers */
1012 /*-----------------------------------------------------------------*/
1014 reassignLR (operand * op)
1016 symbol *sym = OP_SYMBOL (op);
1019 /* not spilt any more */
1020 sym->isspilt = sym->spillA = sym->blockSpil = sym->remainSpil = 0;
1021 bitVectUnSetBit (_G.spiltSet, sym->key);
1023 _G.regAssigned = bitVectSetBit (_G.regAssigned, sym->key);
1024 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, sym->key);
1028 for (i = 0; i < sym->nRegs; i++)
1029 sym->regs[i]->isFree = 0;
1032 /*-----------------------------------------------------------------*/
1033 /* willCauseSpill - determines if allocating will cause a spill */
1034 /*-----------------------------------------------------------------*/
1036 willCauseSpill (int nr, int rt)
1038 /* first check if there are any avlb registers
1039 of te type required */
1042 /* special case for pointer type
1043 if pointer type not avlb then
1044 check for type gpr */
1045 if (nFreeRegs (rt) >= nr)
1047 if (nFreeRegs (REG_GPR) >= nr)
1052 if (ds390_ptrRegReq)
1054 if (nFreeRegs (rt) >= nr)
1059 if (nFreeRegs (REG_PTR) +
1060 nFreeRegs (REG_GPR) >= nr)
1065 /* it will cause a spil */
1069 /*-----------------------------------------------------------------*/
1070 /* positionRegs - the allocator can allocate same registers to res- */
1071 /* ult and operand, if this happens make sure they are in the same */
1072 /* position as the operand otherwise chaos results */
1073 /*-----------------------------------------------------------------*/
1075 positionRegs (symbol * result, symbol * opsym)
1077 int count = min (result->nRegs, opsym->nRegs);
1078 int i, j = 0, shared = 0;
1081 /* if the result has been spilt then cannot share */
1086 /* first make sure that they actually share */
1087 for (i = 0; i < count; i++)
1089 for (j = 0; j < count; j++)
1091 if (result->regs[i] == opsym->regs[j] && i != j)
1101 regs *tmp = result->regs[i];
1102 result->regs[i] = result->regs[j];
1103 result->regs[j] = tmp;
1110 /*-----------------------------------------------------------------*/
1111 /* unusedLRS - returns a bitVector of liveranges not used in 'ebp' */
1112 /*-----------------------------------------------------------------*/
1113 bitVect *unusedLRs (eBBlock *ebp)
1115 bitVect *ret = NULL;
1119 if (!ebp) return NULL;
1120 for (sym = hTabFirstItem(liveRanges,&key); sym ;
1121 sym = hTabNextItem(liveRanges,&key)) {
1123 if (notUsedInBlock(sym,ebp,NULL)) {
1124 ret = bitVectSetBit(ret,sym->key);
1131 /*-----------------------------------------------------------------*/
1132 /* deassignUnsedLRs - if this baisc block ends in a return then */
1133 /* deassign symbols not used in this block */
1134 /*-----------------------------------------------------------------*/
1135 bitVect *deassignUnsedLRs(eBBlock *ebp)
1137 bitVect *unused = NULL;
1140 switch (returnAtEnd(ebp)) {
1141 case 2: /* successor block ends in a return */
1142 unused = unusedLRs((eBBlock *) setFirstItem(ebp->succList));
1144 case 1: /* this block ends in a return */
1145 unused = bitVectIntersect(unused,unusedLRs(ebp));
1150 for (i = 0 ; i < unused->size ; i++ ) {
1153 if (bitVectBitValue(unused,i)) {
1155 /* if assigned to registers */
1156 if (bitVectBitValue(_G.regAssigned,i)) {
1160 sym = hTabItemWithKey(liveRanges,i);
1161 /* remove it from regassigned & mark the
1163 bitVectUnSetBit(_G.regAssigned,i);
1164 for (j = 0 ; j < sym->nRegs; j++)
1165 freeReg(sym->regs[j]);
1167 /* not assigned to registers : remove from set*/
1168 bitVectUnSetBit(unused,i);
1176 /*-----------------------------------------------------------------*/
1177 /* reassignUnusedLRs - put registers to unused Live ranges */
1178 /*-----------------------------------------------------------------*/
1179 void reassignUnusedLRs (bitVect *unused)
1182 if (!unused) return ;
1184 for (i = 0 ; i < unused->size ; i++ ) {
1185 /* if unused : means it was assigned to registers before */
1186 if (bitVectBitValue(unused,i)) {
1190 /* put it back into reg set*/
1191 bitVectSetBit(_G.regAssigned,i) ;
1193 sym = hTabItemWithKey(liveRanges,i);
1194 /* makr registers busy */
1195 for (j = 0 ; j < sym->nRegs; j++)
1196 sym->regs[j]->isFree = 0;
1201 /*-----------------------------------------------------------------*/
1202 /* serialRegAssign - serially allocate registers to the variables */
1203 /*-----------------------------------------------------------------*/
1205 serialRegAssign (eBBlock ** ebbs, int count)
1209 /* for all blocks */
1210 for (i = 0; i < count; i++)
1214 bitVect *unusedLRs = NULL;
1216 if (ebbs[i]->noPath &&
1217 (ebbs[i]->entryLabel != entryLabel &&
1218 ebbs[i]->entryLabel != returnLabel))
1221 unusedLRs = deassignUnsedLRs(ebbs[i]);
1223 /* of all instructions do */
1224 for (ic = ebbs[i]->sch; ic; ic = ic->next)
1227 /* if this is an ipop that means some live
1228 range will have to be assigned again */
1230 reassignLR (IC_LEFT (ic));
1232 /* if result is present && is a true symbol */
1233 if (IC_RESULT (ic) && ic->op != IFX &&
1234 IS_TRUE_SYMOP (IC_RESULT (ic)))
1235 OP_SYMBOL (IC_RESULT (ic))->allocreq++;
1237 /* take away registers from live
1238 ranges that end at this instruction */
1239 deassignLRs (ic, ebbs[i]);
1241 /* some don't need registers */
1242 if (SKIP_IC2 (ic) ||
1243 ic->op == JUMPTABLE ||
1247 (IC_RESULT (ic) && POINTER_SET (ic)))
1250 /* now we need to allocate registers
1251 only for the result */
1254 symbol *sym = OP_SYMBOL (IC_RESULT (ic));
1260 /* if it does not need or is spilt
1261 or is already assigned to registers
1262 or will not live beyond this instructions */
1265 bitVectBitValue (_G.regAssigned, sym->key) ||
1266 sym->liveTo <= ic->seq)
1269 /* if some liverange has been spilt at the block level
1270 and this one live beyond this block then spil this
1272 if (_G.blockSpil && sym->liveTo > ebbs[i]->lSeq)
1277 /* if trying to allocate this will cause
1278 a spill and there is nothing to spill
1279 or this one is rematerializable then
1281 willCS = willCauseSpill (sym->nRegs, sym->regType);
1282 spillable = computeSpillable (ic);
1284 (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)) {
1315 /* if we need ptr regs for the right side
1317 if (POINTER_GET (ic) && IS_SYMOP (IC_LEFT (ic))
1318 && getSize (OP_SYMBOL (IC_LEFT (ic))->type)
1319 <= (unsigned) PTRSIZE)
1324 /* else we assign registers to it */
1325 _G.regAssigned = bitVectSetBit (_G.regAssigned, sym->key);
1326 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, sym->key);
1328 for (j = 0; j < sym->nRegs; j++)
1330 if (sym->regType == REG_PTR)
1331 sym->regs[j] = getRegPtr (ic, ebbs[i], sym);
1333 sym->regs[j] = getRegGpr (ic, ebbs[i], sym);
1335 /* if the allocation falied which means
1336 this was spilt then break */
1340 /* if it shares registers with operands make sure
1341 that they are in the same position */
1342 if (IC_LEFT (ic) && IS_SYMOP (IC_LEFT (ic)) &&
1343 OP_SYMBOL (IC_LEFT (ic))->nRegs && ic->op != '=')
1344 positionRegs (OP_SYMBOL (IC_RESULT (ic)),
1345 OP_SYMBOL (IC_LEFT (ic)));
1346 /* do the same for the right operand */
1347 if (IC_RIGHT (ic) && IS_SYMOP (IC_RIGHT (ic)) &&
1348 OP_SYMBOL (IC_RIGHT (ic))->nRegs)
1349 positionRegs (OP_SYMBOL (IC_RESULT (ic)),
1350 OP_SYMBOL (IC_RIGHT (ic)));
1360 reassignUnusedLRs(unusedLRs);
1364 /*-----------------------------------------------------------------*/
1365 /* fillGaps - Try to fill in the Gaps left by Pass1 */
1366 /*-----------------------------------------------------------------*/
1367 static void fillGaps()
1371 int loop = 0, change;
1373 if (getenv("DISABLE_FILL_GAPS")) return;
1375 /* First try to do DPTRuse once more since now we know what got into
1378 while (loop++ < 10) {
1381 for (sym = hTabFirstItem(liveRanges,&key) ; sym ;
1382 sym = hTabNextItem(liveRanges,&key)) {
1383 int size = getSize(sym->type);
1385 if (sym->liveFrom == sym->liveTo) continue;
1387 if (sym->uptr && sym->dptr==0 && !sym->ruonly &&
1388 size < 4 && size > 1) {
1390 if (packRegsDPTRuse(operandFromSymbol(sym))) {
1392 /* if this was ssigned to registers then */
1393 if (bitVectBitValue(_G.totRegAssigned,sym->key)) {
1394 /* take it out of the register assigned set */
1395 bitVectUnSetBit(_G.totRegAssigned,sym->key);
1396 } else if (sym->usl.spillLoc) {
1397 sym->usl.spillLoc->allocreq--;
1398 sym->usl.spillLoc = NULL;
1402 sym->isspilt = sym->spillA = 0;
1406 /* try assigning other dptrs */
1407 if (sym->dptr == 0 && packRegsDPTRnuse(operandFromSymbol(sym),1) && !getenv("DPTRnDISABLE")) {
1408 /* if this was ssigned to registers then */
1409 if (bitVectBitValue(_G.totRegAssigned,sym->key)) {
1410 /* take it out of the register assigned set */
1411 bitVectUnSetBit(_G.totRegAssigned,sym->key);
1412 } else if (sym->usl.spillLoc) {
1413 sym->usl.spillLoc->allocreq--;
1414 sym->usl.spillLoc = NULL;
1417 sym->isspilt = sym->spillA = 0;
1422 /* look for livernages that was spilt by the allocator */
1423 for (sym = hTabFirstItem(liveRanges,&key) ; sym ;
1424 sym = hTabNextItem(liveRanges,&key)) {
1429 if (!sym->spillA || !sym->clashes || sym->remat) continue ;
1430 if (!sym->uses || !sym->defs) continue ;
1431 /* find the liveRanges this one clashes with, that are
1432 still assigned to registers & mark the registers as used*/
1433 for ( i = 0 ; i < sym->clashes->size ; i ++) {
1437 if (bitVectBitValue(sym->clashes,i) == 0 || /* those that clash with this */
1438 bitVectBitValue(_G.totRegAssigned,i) == 0) /* and are still assigned to registers */
1441 clr = hTabItemWithKey(liveRanges,i);
1444 /* mark these registers as used */
1445 for (k = 0 ; k < clr->nRegs ; k++ )
1446 useReg(clr->regs[k]);
1449 if (willCauseSpill(sym->nRegs,sym->regType)) {
1450 /* NOPE :( clear all registers & and continue */
1455 /* THERE IS HOPE !!!! */
1456 for (i=0; i < sym->nRegs ; i++ ) {
1457 if (sym->regType == REG_PTR)
1458 sym->regs[i] = getRegPtrNoSpil ();
1460 sym->regs[i] = getRegGprNoSpil ();
1463 /* for all its definitions & uses check if the registers
1464 allocated needs positioning NOTE: we can position
1465 only ONCE if more than One positioning required
1468 for (i = 0 ; i < sym->defs->size ; i++ ) {
1469 if (bitVectBitValue(sym->defs,i)) {
1471 if (!(ic = hTabItemWithKey(iCodehTab,i))) continue ;
1472 if (SKIP_IC(ic)) continue;
1473 assert(isSymbolEqual(sym,OP_SYMBOL(IC_RESULT(ic)))); /* just making sure */
1474 /* if left is assigned to registers */
1475 if (IS_SYMOP(IC_LEFT(ic)) &&
1476 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_LEFT(ic))->key)) {
1477 pdone += positionRegs(sym,OP_SYMBOL(IC_LEFT(ic)));
1479 if (IS_SYMOP(IC_RIGHT(ic)) &&
1480 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_RIGHT(ic))->key)) {
1481 pdone += positionRegs(sym,OP_SYMBOL(IC_RIGHT(ic)));
1483 if (pdone > 1) break;
1486 for (i = 0 ; i < sym->uses->size ; i++ ) {
1487 if (bitVectBitValue(sym->uses,i)) {
1489 if (!(ic = hTabItemWithKey(iCodehTab,i))) continue ;
1490 if (SKIP_IC(ic)) continue;
1491 if (!IS_ASSIGN_ICODE(ic)) continue ;
1493 /* if result is assigned to registers */
1494 if (IS_SYMOP(IC_RESULT(ic)) &&
1495 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_RESULT(ic))->key)) {
1496 pdone += positionRegs(sym,OP_SYMBOL(IC_RESULT(ic)));
1498 if (pdone > 1) break;
1501 /* had to position more than once GIVE UP */
1503 /* UNDO all the changes we made to try this */
1505 for (i=0; i < sym->nRegs ; i++ ) {
1506 sym->regs[i] = NULL;
1509 D (fprintf (stderr, "Fill Gap gave up due to positioning for "
1510 "%s in function %s\n",
1511 sym->name, currFunc ? currFunc->name : "UNKNOWN"));
1514 D (fprintf (stderr, "FILLED GAP for %s in function %s\n",
1515 sym->name, currFunc ? currFunc->name : "UNKNOWN"));
1516 _G.totRegAssigned = bitVectSetBit(_G.totRegAssigned,sym->key);
1517 sym->isspilt = sym->spillA = 0 ;
1518 sym->usl.spillLoc->allocreq--;
1519 sym->usl.spillLoc = NULL;
1527 /*-----------------------------------------------------------------*/
1528 /* rUmaskForOp :- returns register mask for an operand */
1529 /*-----------------------------------------------------------------*/
1531 ds390_rUmaskForOp (operand * op)
1537 /* only temporaries are assigned registers */
1541 sym = OP_SYMBOL (op);
1543 /* if spilt or no registers assigned to it
1545 if (sym->isspilt || !sym->nRegs)
1548 rumask = newBitVect (ds390_nRegs);
1550 for (j = 0; j < sym->nRegs; j++)
1552 rumask = bitVectSetBit (rumask,
1553 sym->regs[j]->rIdx);
1559 /*-----------------------------------------------------------------*/
1560 /* regsUsedIniCode :- returns bit vector of registers used in iCode */
1561 /*-----------------------------------------------------------------*/
1563 regsUsedIniCode (iCode * ic)
1565 bitVect *rmask = newBitVect (ds390_nRegs);
1567 /* do the special cases first */
1570 rmask = bitVectUnion (rmask,
1571 ds390_rUmaskForOp (IC_COND (ic)));
1575 /* for the jumptable */
1576 if (ic->op == JUMPTABLE)
1578 rmask = bitVectUnion (rmask,
1579 ds390_rUmaskForOp (IC_JTCOND (ic)));
1584 /* of all other cases */
1586 rmask = bitVectUnion (rmask,
1587 ds390_rUmaskForOp (IC_LEFT (ic)));
1591 rmask = bitVectUnion (rmask,
1592 ds390_rUmaskForOp (IC_RIGHT (ic)));
1595 rmask = bitVectUnion (rmask,
1596 ds390_rUmaskForOp (IC_RESULT (ic)));
1602 /*-----------------------------------------------------------------*/
1603 /* createRegMask - for each instruction will determine the regsUsed */
1604 /*-----------------------------------------------------------------*/
1606 createRegMask (eBBlock ** ebbs, int count)
1610 /* for all blocks */
1611 for (i = 0; i < count; i++)
1615 if (ebbs[i]->noPath &&
1616 (ebbs[i]->entryLabel != entryLabel &&
1617 ebbs[i]->entryLabel != returnLabel))
1620 /* for all instructions */
1621 for (ic = ebbs[i]->sch; ic; ic = ic->next)
1626 if (SKIP_IC2 (ic) || !ic->rlive)
1629 /* first mark the registers used in this
1631 ic->rUsed = regsUsedIniCode (ic);
1632 _G.funcrUsed = bitVectUnion (_G.funcrUsed, ic->rUsed);
1634 /* now create the register mask for those
1635 registers that are in use : this is a
1636 super set of ic->rUsed */
1637 ic->rMask = newBitVect (ds390_nRegs + 1);
1639 /* for all live Ranges alive at this point */
1640 for (j = 1; j < ic->rlive->size; j++)
1645 /* if not alive then continue */
1646 if (!bitVectBitValue (ic->rlive, j))
1649 /* find the live range we are interested in */
1650 if (!(sym = hTabItemWithKey (liveRanges, j)))
1652 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
1653 "createRegMask cannot find live range");
1657 /* special case for ruonly */
1658 if (sym->ruonly && sym->liveFrom != sym->liveTo) {
1659 int size = getSize(sym->type);
1661 for (k = 0 ; k < size; k++ )
1662 ic->rMask = bitVectSetBit (ic->rMask, j++);
1665 /* if no register assigned to it */
1666 if (!sym->nRegs || sym->isspilt)
1669 /* for all the registers allocated to it */
1670 for (k = 0; k < sym->nRegs; k++)
1673 bitVectSetBit (ic->rMask, sym->regs[k]->rIdx);
1679 /*-----------------------------------------------------------------*/
1680 /* rematStr - returns the rematerialized string for a remat var */
1681 /*-----------------------------------------------------------------*/
1683 rematStr (symbol * sym)
1686 iCode *ic = sym->rematiCode;
1693 /* if plus or minus print the right hand side */
1694 if (ic->op == '+' || ic->op == '-')
1696 SNPRINTF (s, sizeof(buffer) - strlen(buffer),
1697 "0x%04x %c ", (int) operandLitValue (IC_RIGHT (ic)),
1700 ic = OP_SYMBOL (IC_LEFT (ic))->rematiCode;
1703 /* cast then continue */
1704 if (IS_CAST_ICODE(ic)) {
1705 ic = OP_SYMBOL (IC_RIGHT (ic))->rematiCode;
1708 /* we reached the end */
1709 SNPRINTF (s, sizeof(buffer) - strlen(buffer),
1710 "%s", OP_SYMBOL (IC_LEFT (ic))->rname);
1717 /*-----------------------------------------------------------------*/
1718 /* regTypeNum - computes the type & number of registers required */
1719 /*-----------------------------------------------------------------*/
1727 /* for each live range do */
1728 for (sym = hTabFirstItem (liveRanges, &k); sym;
1729 sym = hTabNextItem (liveRanges, &k))
1732 /* if used zero times then no registers needed */
1733 if ((sym->liveTo - sym->liveFrom) == 0)
1737 /* if the live range is a temporary */
1741 /* if the type is marked as a conditional */
1742 if (sym->regType == REG_CND)
1745 /* if used in return only then we don't
1747 if (sym->ruonly || sym->accuse)
1749 if (IS_AGGREGATE (sym->type) || sym->isptr)
1750 sym->type = aggrToPtr (sym->type, FALSE);
1754 /* if the symbol has only one definition &
1755 that definition is a get_pointer */
1756 if (bitVectnBitsOn (sym->defs) == 1 &&
1757 (ic = hTabItemWithKey (iCodehTab,
1758 bitVectFirstBit (sym->defs))) &&
1761 !IS_BITVAR (sym->etype))
1763 /* and that pointer is remat in data space */
1764 if (IS_SYMOP (IC_LEFT (ic)) &&
1765 OP_SYMBOL (IC_LEFT (ic))->remat &&
1766 !IS_CAST_ICODE(OP_SYMBOL (IC_LEFT (ic))->rematiCode) &&
1767 DCL_TYPE (aggrToPtr (operandType(IC_LEFT(ic)), FALSE)) == POINTER)
1770 /* create a psuedo symbol & force a spil */
1771 symbol *psym = newSymbol (rematStr (OP_SYMBOL (IC_LEFT (ic))), 1);
1772 psym->type = sym->type;
1773 psym->etype = sym->etype;
1774 strncpyz (psym->rname, psym->name, sizeof(psym->rname));
1776 sym->usl.spillLoc = psym;
1780 /* if in data space or idata space then try to
1781 allocate pointer register */
1785 /* if not then we require registers */
1786 sym->nRegs = ((IS_AGGREGATE (sym->type) || sym->isptr) ?
1787 getSize (sym->type = aggrToPtr (sym->type, FALSE)) :
1788 getSize (sym->type));
1792 fprintf (stderr, "allocated more than 4 or 0 registers for type ");
1793 printTypeChain (sym->type, stderr);
1794 fprintf (stderr, "\n");
1797 /* determine the type of register required */
1798 if (sym->nRegs == 1 &&
1799 IS_PTR (sym->type) &&
1801 sym->regType = REG_PTR;
1803 sym->regType = REG_GPR;
1807 /* for the first run we don't provide */
1808 /* registers for true symbols we will */
1809 /* see how things go */
1815 /*-----------------------------------------------------------------*/
1816 /* freeAllRegs - mark all registers as free */
1817 /*-----------------------------------------------------------------*/
1823 for (i = 0; i < ds390_nRegs; i++)
1824 regs390[i].isFree = 1;
1827 /*-----------------------------------------------------------------*/
1828 /* deallocStackSpil - this will set the stack pointer back */
1829 /*-----------------------------------------------------------------*/
1831 DEFSETFUNC (deallocStackSpil)
1839 /*-----------------------------------------------------------------*/
1840 /* farSpacePackable - returns the packable icode for far variables */
1841 /*-----------------------------------------------------------------*/
1843 farSpacePackable (iCode * ic)
1847 /* go thru till we find a definition for the
1848 symbol on the right */
1849 for (dic = ic->prev; dic; dic = dic->prev)
1852 /* if the definition is a call then no */
1853 if ((dic->op == CALL || dic->op == PCALL) &&
1854 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1859 /* if shift by unknown amount then not */
1860 if ((dic->op == LEFT_OP || dic->op == RIGHT_OP) &&
1861 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1864 /* if pointer get and size > 1 */
1865 if (POINTER_GET (dic) &&
1866 getSize (aggrToPtr (operandType (IC_LEFT (dic)), FALSE)) > 1)
1869 if (POINTER_SET (dic) &&
1870 getSize (aggrToPtr (operandType (IC_RESULT (dic)), FALSE)) > 1)
1873 /* if any three is a true symbol in far space */
1874 if (IC_RESULT (dic) &&
1875 IS_TRUE_SYMOP (IC_RESULT (dic)) &&
1876 isOperandInFarSpace (IC_RESULT (dic)))
1879 if (IC_RIGHT (dic) &&
1880 IS_TRUE_SYMOP (IC_RIGHT (dic)) &&
1881 isOperandInFarSpace (IC_RIGHT (dic)) &&
1882 !isOperandEqual (IC_RIGHT (dic), IC_RESULT (ic)))
1885 if (IC_LEFT (dic) &&
1886 IS_TRUE_SYMOP (IC_LEFT (dic)) &&
1887 isOperandInFarSpace (IC_LEFT (dic)) &&
1888 !isOperandEqual (IC_LEFT (dic), IC_RESULT (ic)))
1891 if (isOperandEqual (IC_RIGHT (ic), IC_RESULT (dic)))
1893 if ((dic->op == LEFT_OP ||
1894 dic->op == RIGHT_OP ||
1896 IS_OP_LITERAL (IC_RIGHT (dic)))
1906 /*-----------------------------------------------------------------*/
1907 /* packRegsForAssign - register reduction for assignment */
1908 /*-----------------------------------------------------------------*/
1910 packRegsForAssign (iCode * ic, eBBlock * ebp)
1914 if (!IS_ITEMP (IC_RIGHT (ic)) ||
1915 OP_SYMBOL (IC_RIGHT (ic))->isind ||
1916 OP_LIVETO (IC_RIGHT (ic)) > ic->seq)
1921 /* if the true symbol is defined in far space or on stack
1922 then we should not since this will increase register pressure */
1924 if (isOperandInFarSpace (IC_RESULT (ic)))
1926 if ((dic = farSpacePackable (ic)))
1932 if (isOperandInFarSpace(IC_RESULT(ic)) && !farSpacePackable(ic)) {
1937 /* find the definition of iTempNN scanning backwards if we find a
1938 a use of the true symbol in before we find the definition then
1940 for (dic = ic->prev; dic; dic = dic->prev)
1942 /* if there is a function call then don't pack it */
1943 if ((dic->op == CALL || dic->op == PCALL))
1952 if (IS_TRUE_SYMOP (IC_RESULT (dic)) &&
1953 IS_OP_VOLATILE (IC_RESULT (dic)))
1959 if (IS_SYMOP (IC_RESULT (dic)) &&
1960 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1962 if (POINTER_SET (dic))
1968 if (IS_SYMOP (IC_RIGHT (dic)) &&
1969 (IC_RIGHT (dic)->key == IC_RESULT (ic)->key ||
1970 IC_RIGHT (dic)->key == IC_RIGHT (ic)->key))
1976 if (IS_SYMOP (IC_LEFT (dic)) &&
1977 (IC_LEFT (dic)->key == IC_RESULT (ic)->key ||
1978 IC_LEFT (dic)->key == IC_RIGHT (ic)->key))
1984 if (POINTER_SET (dic) &&
1985 IC_RESULT (dic)->key == IC_RESULT (ic)->key)
1993 return 0; /* did not find */
1995 /* if the result is on stack or iaccess then it must be
1996 the same atleast one of the operands */
1997 if (OP_SYMBOL (IC_RESULT (ic))->onStack ||
1998 OP_SYMBOL (IC_RESULT (ic))->iaccess)
2001 /* the operation has only one symbol
2002 operator then we can pack */
2003 if ((IC_LEFT (dic) && !IS_SYMOP (IC_LEFT (dic))) ||
2004 (IC_RIGHT (dic) && !IS_SYMOP (IC_RIGHT (dic))))
2007 if (!((IC_LEFT (dic) &&
2008 IC_RESULT (ic)->key == IC_LEFT (dic)->key) ||
2010 IC_RESULT (ic)->key == IC_RIGHT (dic)->key)))
2014 /* found the definition */
2015 /* replace the result with the result of */
2016 /* this assignment and remove this assignment */
2017 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2019 IC_RESULT (dic) = IC_RESULT (ic);
2021 if (IS_ITEMP (IC_RESULT (dic)) && OP_SYMBOL (IC_RESULT (dic))->liveFrom > dic->seq)
2023 OP_SYMBOL (IC_RESULT (dic))->liveFrom = dic->seq;
2025 /* delete from liverange table also
2026 delete from all the points inbetween and the new
2028 for (sic = dic; sic != ic; sic = sic->next)
2030 bitVectUnSetBit (sic->rlive, IC_RESULT (ic)->key);
2031 if (IS_ITEMP (IC_RESULT (dic)))
2032 bitVectSetBit (sic->rlive, IC_RESULT (dic)->key);
2035 remiCodeFromeBBlock (ebp, ic);
2036 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
2037 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
2038 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
2043 /*-----------------------------------------------------------------*/
2044 /* findAssignToSym : scanning backwards looks for first assig found */
2045 /*-----------------------------------------------------------------*/
2047 findAssignToSym (operand * op, iCode * ic)
2051 for (dic = ic->prev; dic; dic = dic->prev)
2054 /* if definition by assignment */
2055 if (dic->op == '=' &&
2056 !POINTER_SET (dic) &&
2057 IC_RESULT (dic)->key == op->key
2058 /* && IS_TRUE_SYMOP(IC_RIGHT(dic)) */
2062 /* we are interested only if defined in far space */
2063 /* or in stack space in case of + & - */
2065 /* if assigned to a non-symbol then return
2067 if (!IS_SYMOP (IC_RIGHT (dic)))
2070 /* if the symbol is in far space then
2072 if (isOperandInFarSpace (IC_RIGHT (dic)))
2075 /* for + & - operations make sure that
2076 if it is on the stack it is the same
2077 as one of the three operands */
2078 if ((ic->op == '+' || ic->op == '-') &&
2079 OP_SYMBOL (IC_RIGHT (dic))->onStack)
2082 if (IC_RESULT (ic)->key != IC_RIGHT (dic)->key &&
2083 IC_LEFT (ic)->key != IC_RIGHT (dic)->key &&
2084 IC_RIGHT (ic)->key != IC_RIGHT (dic)->key)
2092 /* if we find an usage then we cannot delete it */
2093 if (IC_LEFT (dic) && IC_LEFT (dic)->key == op->key)
2096 if (IC_RIGHT (dic) && IC_RIGHT (dic)->key == op->key)
2099 if (POINTER_SET (dic) && IC_RESULT (dic)->key == op->key)
2103 /* now make sure that the right side of dic
2104 is not defined between ic & dic */
2107 iCode *sic = dic->next;
2109 for (; sic != ic; sic = sic->next)
2110 if (IC_RESULT (sic) &&
2111 IC_RESULT (sic)->key == IC_RIGHT (dic)->key)
2120 /*-----------------------------------------------------------------*/
2121 /* packRegsForSupport :- reduce some registers for support calls */
2122 /*-----------------------------------------------------------------*/
2124 packRegsForSupport (iCode * ic, eBBlock * ebp)
2128 /* for the left & right operand :- look to see if the
2129 left was assigned a true symbol in far space in that
2130 case replace them */
2131 if (IS_ITEMP (IC_LEFT (ic)) &&
2132 OP_SYMBOL (IC_LEFT (ic))->liveTo <= ic->seq)
2134 iCode *dic = findAssignToSym (IC_LEFT (ic), ic);
2140 /* found it we need to remove it from the
2142 for (sic = dic; sic != ic; sic = sic->next) {
2143 bitVectUnSetBit (sic->rlive, IC_LEFT (ic)->key);
2144 sic->rlive = bitVectSetBit (sic->rlive, IC_RIGHT (dic)->key);
2147 wassert(IS_SYMOP(IC_LEFT (ic)));
2148 wassert(IS_SYMOP(IC_RIGHT (dic)));
2149 IC_LEFT (ic)->operand.symOperand =
2150 IC_RIGHT (dic)->operand.symOperand;
2151 OP_SYMBOL(IC_LEFT(ic))->liveTo = ic->seq;
2152 IC_LEFT (ic)->key = IC_RIGHT (dic)->operand.symOperand->key;
2153 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2154 remiCodeFromeBBlock (ebp, dic);
2155 hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
2159 /* do the same for the right operand */
2162 IS_ITEMP (IC_RIGHT (ic)) &&
2163 OP_SYMBOL (IC_RIGHT (ic))->liveTo <= ic->seq)
2165 iCode *dic = findAssignToSym (IC_RIGHT (ic), ic);
2171 /* if this is a subtraction & the result
2172 is a true symbol in far space then don't pack */
2173 if (ic->op == '-' && IS_TRUE_SYMOP (IC_RESULT (dic)))
2175 sym_link *etype = getSpec (operandType (IC_RESULT (dic)));
2176 if (IN_FARSPACE (SPEC_OCLS (etype)))
2179 /* found it we need to remove it from the
2181 for (sic = dic; sic != ic; sic = sic->next) {
2182 bitVectUnSetBit (sic->rlive, IC_RIGHT (ic)->key);
2183 sic->rlive = bitVectSetBit (sic->rlive, IC_RIGHT (dic)->key);
2186 wassert(IS_SYMOP(IC_RIGHT (ic)));
2187 wassert(IS_SYMOP(IC_RIGHT (dic)));
2188 IC_RIGHT (ic)->operand.symOperand =
2189 IC_RIGHT (dic)->operand.symOperand;
2190 IC_RIGHT (ic)->key = IC_RIGHT (dic)->operand.symOperand->key;
2191 OP_SYMBOL(IC_RIGHT(ic))->liveTo = ic->seq;
2192 remiCodeFromeBBlock (ebp, dic);
2193 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2194 hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
2201 #define IS_OP_RUONLY(x) (x && IS_SYMOP(x) && OP_SYMBOL(x)->ruonly)
2204 /*-----------------------------------------------------------------*/
2205 /* packRegsDPTRnuse - color live ranges that can go into extra DPTRS */
2206 /*-----------------------------------------------------------------*/
2207 static int packRegsDPTRnuse( operand *op , int dptr)
2212 if (!IS_SYMOP(op) || !IS_ITEMP(op)) return 0;
2213 if (OP_SYMBOL(op)->remat || OP_SYMBOL(op)->ruonly || OP_SYMBOL(op)->dptr)
2216 /* first check if any overlapping liverange has already been
2217 assigned to this DPTR */
2218 if (OP_SYMBOL(op)->clashes) {
2219 for (i = 0 ; i < OP_SYMBOL(op)->clashes->size ; i++ ) {
2221 if (bitVectBitValue(OP_SYMBOL(op)->clashes,i)) {
2222 sym = hTabItemWithKey(liveRanges,i);
2223 if (sym->dptr == dptr) return 0;
2228 /* future for more dptrs */
2230 OP_SYMBOL(op)->dptr = dptr;
2234 /* DPTR1 is special since it is also used as a scratch by the backend .
2235 so we walk thru the entire live range of this operand and make sure
2236 DPTR1 will not be used by the backed . The logic here is to find out if
2237 more than one operand in an icode is in far space then we give up : we
2238 don't keep it live across functions for now
2241 ic = hTabFirstItemWK(iCodeSeqhTab,OP_SYMBOL(op)->liveFrom);
2242 for (; ic && ic->seq <= OP_SYMBOL(op)->liveTo;
2243 ic = hTabNextItem(iCodeSeqhTab,&key)) {
2246 if (ic->op == CALL || ic->op == PCALL) return 0;
2248 /* single operand icode are ok */
2249 if (ic->op == IFX || ic->op == IPUSH)
2252 if (ic->op == SEND ) {
2253 if (ic->argreg != 1 ) return 0;
2256 /* two special cases first */
2257 if (POINTER_GET(ic) && !isOperandEqual(IC_LEFT(ic),op) && /* pointer get */
2258 !OP_SYMBOL(IC_LEFT(ic))->ruonly && /* with result in far space */
2259 (isOperandInFarSpace(IC_RESULT(ic)) &&
2260 !isOperandInReg(IC_RESULT(ic)))) {
2264 if (POINTER_SET(ic) && !isOperandEqual(IC_RESULT(ic),op) && /* pointer set */
2265 !OP_SYMBOL(IC_RESULT(ic))->ruonly && /* with right in far space */
2266 (isOperandInFarSpace(IC_RIGHT(ic)) &&
2267 !isOperandInReg(IC_RIGHT(ic)))) {
2271 if (IC_RESULT(ic) && IS_SYMOP(IC_RESULT(ic)) && /* if symbol operand */
2272 !isOperandEqual(IC_RESULT(ic),op) && /* not the same as this */
2273 ((isOperandInFarSpace(IC_RESULT(ic)) || /* in farspace or */
2274 OP_SYMBOL(IC_RESULT(ic))->onStack) && /* on the stack */
2275 !isOperandInReg(IC_RESULT(ic)))) { /* and not in register */
2279 if (IC_LEFT(ic) && IS_SYMOP(IC_LEFT(ic)) && /* if symbol operand */
2280 !isOperandEqual(IC_LEFT(ic),op) && /* not the same as this */
2281 ((isOperandInFarSpace(IC_LEFT(ic)) || /* in farspace or */
2282 OP_SYMBOL(IC_LEFT(ic))->onStack) && /* on the stack */
2283 !isOperandInReg(IC_LEFT(ic)))) { /* and not in register */
2286 /* same for right */
2287 if (IC_RIGHT(ic) && IS_SYMOP(IC_RIGHT(ic)) && /* if symbol operand */
2288 !isOperandEqual(IC_RIGHT(ic),op) && /* not the same as this */
2289 ((isOperandInFarSpace(IC_RIGHT(ic)) || /* in farspace or */
2290 OP_SYMBOL(IC_RIGHT(ic))->onStack) && /* on the stack */
2291 !isOperandInReg(IC_RIGHT(ic)))) { /* and not in register */
2295 if (nfs && IC_RESULT(ic) && IS_SYMOP(IC_RESULT(ic)) &&
2296 OP_SYMBOL(IC_RESULT(ic))->ruonly) return 0;
2298 if (nfs > 1) return 0;
2300 OP_SYMBOL(op)->dptr = dptr;
2304 /*-----------------------------------------------------------------*/
2305 /* packRegsDPTRuse : - will reduce some registers for single Use */
2306 /*-----------------------------------------------------------------*/
2308 packRegsDPTRuse (operand * op)
2310 /* go thru entire liveRange of this variable & check for
2311 other possible usage of DPTR , if we don't find it the
2312 assign this to DPTR (ruonly)
2317 sym_link *type, *etype;
2319 if (!IS_SYMOP(op) || !IS_ITEMP(op)) return NULL;
2320 if (OP_SYMBOL(op)->remat || OP_SYMBOL(op)->ruonly) return NULL;
2322 /* first check if any overlapping liverange has already been
2324 if (OP_SYMBOL(op)->clashes) {
2325 for (i = 0 ; i < OP_SYMBOL(op)->clashes->size ; i++ ) {
2326 if (bitVectBitValue(OP_SYMBOL(op)->clashes,i)) {
2327 sym = hTabItemWithKey(liveRanges,i);
2328 if (sym->ruonly) return NULL ;
2333 /* no then go thru this guys live range */
2334 dic = ic = hTabFirstItemWK(iCodeSeqhTab,OP_SYMBOL(op)->liveFrom);
2335 for (; ic && ic->seq <= OP_SYMBOL(op)->liveTo;
2336 ic = hTabNextItem(iCodeSeqhTab,&key)) {
2338 if (SKIP_IC3(ic)) continue;
2340 /* if PCALL cannot be sure give up */
2341 if (ic->op == PCALL) return NULL;
2343 /* if SEND & not the first parameter then giveup */
2344 if (ic->op == SEND && ic->argreg != 1 &&
2345 ((isOperandInFarSpace(IC_LEFT(ic)) && !isOperandInReg(IC_LEFT(ic))) ||
2346 isOperandEqual(op,IC_LEFT(ic)))) return NULL;
2348 /* if CALL then make sure it is VOID || return value not used
2349 or the return value is assigned to this one */
2350 if (ic->op == CALL) {
2351 if (OP_SYMBOL(IC_RESULT(ic))->liveTo ==
2352 OP_SYMBOL(IC_RESULT(ic))->liveFrom) continue ;
2353 etype = getSpec(type = operandType(IC_RESULT(ic)));
2354 if (getSize(type) == 0 || isOperandEqual(op,IC_RESULT(ic)))
2359 /* special case of add with a [remat] */
2360 if (ic->op == '+' &&
2361 OP_SYMBOL(IC_LEFT(ic))->remat &&
2362 (isOperandInFarSpace(IC_RIGHT(ic)) &&
2363 !isOperandInReg(IC_RIGHT(ic)))) return NULL ;
2367 if (POINTER_GET(ic) && !isOperandEqual(IC_LEFT(ic),op) &&
2368 getSize(operandType(IC_LEFT(ic))) > 1 ) return NULL ;
2371 if (POINTER_SET(ic) && !isOperandEqual(IC_RESULT(ic),op) &&
2372 getSize(operandType(IC_RESULT(ic))) > 1 ) return NULL;
2374 /* conditionals can destroy 'b' - make sure B wont
2375 be used in this one*/
2376 if ((IS_CONDITIONAL(ic) || ic->op == '*' || ic->op == '/' ||
2377 ic->op == LEFT_OP || ic->op == RIGHT_OP ) &&
2378 getSize(operandType(op)) > 3) return NULL;
2380 /* if this is a cast to a bigger type */
2382 if (!IS_PTR(OP_SYM_TYPE(IC_RESULT(ic))) &&
2383 getSize(OP_SYM_TYPE(IC_RESULT(ic))) >
2384 getSize(OP_SYM_TYPE(IC_RIGHT(ic)))) {
2390 if (IC_RESULT(ic) && IS_SYMOP(IC_RESULT(ic)) &&
2391 !isOperandEqual(IC_RESULT(ic),op) &&
2392 ( ( ( isOperandInFarSpace(IC_RESULT(ic)) || OP_SYMBOL(IC_RESULT(ic))->onStack) &&
2393 !isOperandInReg(IC_RESULT(ic))) ||
2394 OP_SYMBOL(IC_RESULT(ic))->ruonly)) return NULL;
2396 if (IC_RIGHT(ic) && IS_SYMOP(IC_RIGHT(ic)) &&
2397 !isOperandEqual(IC_RIGHT(ic),op) &&
2398 (OP_SYMBOL(IC_RIGHT(ic))->liveTo >= ic->seq ||
2399 IS_TRUE_SYMOP(IC_RIGHT(ic)) ||
2400 OP_SYMBOL(IC_RIGHT(ic))->ruonly) &&
2401 ( ( isOperandInFarSpace(IC_RIGHT(ic)) || OP_SYMBOL(IC_RIGHT(ic))->onStack) &&
2402 !isOperandInReg(IC_RIGHT(ic))) ) return NULL;
2404 if (IC_LEFT(ic) && IS_SYMOP(IC_LEFT(ic)) &&
2405 !isOperandEqual(IC_LEFT(ic),op) &&
2406 (OP_SYMBOL(IC_LEFT(ic))->liveTo >= ic->seq ||
2407 IS_TRUE_SYMOP(IC_LEFT(ic)) ||
2408 OP_SYMBOL(IC_LEFT(ic))->ruonly) &&
2409 ( ( isOperandInFarSpace(IC_LEFT(ic)) || OP_SYMBOL(IC_LEFT(ic))->onStack) &&
2410 !isOperandInReg(IC_LEFT(ic))) ) return NULL;
2412 if (IC_LEFT(ic) && IC_RIGHT(ic) &&
2413 IS_ITEMP(IC_LEFT(ic)) && IS_ITEMP(IC_RIGHT(ic)) &&
2414 (isOperandInFarSpace(IC_LEFT(ic)) && !isOperandInReg(IC_LEFT(ic))) &&
2415 (isOperandInFarSpace(IC_RIGHT(ic)) && !isOperandInReg(IC_RIGHT(ic))))
2418 OP_SYMBOL(op)->ruonly = 1;
2419 if (OP_SYMBOL(op)->usl.spillLoc) {
2420 if (OP_SYMBOL(op)->spillA)
2421 OP_SYMBOL(op)->usl.spillLoc->allocreq--;
2422 OP_SYMBOL(op)->usl.spillLoc = NULL;
2427 /*-----------------------------------------------------------------*/
2428 /* isBitwiseOptimizable - requirements of JEAN LOUIS VERN */
2429 /*-----------------------------------------------------------------*/
2431 isBitwiseOptimizable (iCode * ic)
2433 sym_link *ltype = getSpec (operandType (IC_LEFT (ic)));
2434 sym_link *rtype = getSpec (operandType (IC_RIGHT (ic)));
2436 /* bitwise operations are considered optimizable
2437 under the following conditions (Jean-Louis VERN)
2449 if ( IS_LITERAL (rtype) ||
2450 (IS_BITVAR (ltype) && IN_BITSPACE (SPEC_OCLS (ltype))))
2456 /*-----------------------------------------------------------------*/
2457 /* packRegsForAccUse - pack registers for acc use */
2458 /*-----------------------------------------------------------------*/
2460 packRegsForAccUse (iCode * ic)
2464 /* if this is an aggregate, e.g. a one byte char array */
2465 if (IS_AGGREGATE(operandType(IC_RESULT(ic)))) {
2469 /* if we are calling a reentrant function that has stack parameters */
2470 if (ic->op == CALL &&
2471 IFFUNC_ISREENT(operandType(IC_LEFT(ic))) &&
2472 FUNC_HASSTACKPARM(operandType(IC_LEFT(ic))))
2475 if (ic->op == PCALL &&
2476 IFFUNC_ISREENT(operandType(IC_LEFT(ic))->next) &&
2477 FUNC_HASSTACKPARM(operandType(IC_LEFT(ic))->next))
2480 /* if + or - then it has to be one byte result */
2481 if ((ic->op == '+' || ic->op == '-')
2482 && getSize (operandType (IC_RESULT (ic))) > 1)
2485 /* if shift operation make sure right side is not a literal */
2486 if (ic->op == RIGHT_OP &&
2487 (isOperandLiteral (IC_RIGHT (ic)) ||
2488 getSize (operandType (IC_RESULT (ic))) > 1))
2491 if (ic->op == LEFT_OP &&
2492 (isOperandLiteral (IC_RIGHT (ic)) ||
2493 getSize (operandType (IC_RESULT (ic))) > 1))
2496 if (IS_BITWISE_OP (ic) &&
2497 getSize (operandType (IC_RESULT (ic))) > 1)
2501 /* has only one definition */
2502 if (bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) > 1)
2505 /* has only one use */
2506 if (bitVectnBitsOn (OP_USES (IC_RESULT (ic))) > 1)
2509 /* and the usage immediately follows this iCode */
2510 if (!(uic = hTabItemWithKey (iCodehTab,
2511 bitVectFirstBit (OP_USES (IC_RESULT (ic))))))
2514 if (ic->next != uic)
2517 /* if it is a conditional branch then we definitely can */
2521 if (uic->op == JUMPTABLE)
2524 /* if the usage is not is an assignment
2525 or an arithmetic / bitwise / shift operation then not */
2526 if (POINTER_SET (uic) &&
2527 getSize (aggrToPtr (operandType (IC_RESULT (uic)), FALSE)) > 1)
2530 if (uic->op != '=' &&
2531 !IS_ARITHMETIC_OP (uic) &&
2532 !IS_BITWISE_OP (uic) &&
2533 uic->op != LEFT_OP &&
2534 uic->op != RIGHT_OP)
2537 /* if used in ^ operation then make sure right is not a
2539 if (uic->op == '^' && isOperandLiteral (IC_RIGHT (uic)))
2542 /* if shift operation make sure right side is not a literal */
2543 if (uic->op == RIGHT_OP &&
2544 (isOperandLiteral (IC_RIGHT (uic)) ||
2545 getSize (operandType (IC_RESULT (uic))) > 1))
2548 if (uic->op == LEFT_OP &&
2549 (isOperandLiteral (IC_RIGHT (uic)) ||
2550 getSize (operandType (IC_RESULT (uic))) > 1))
2553 /* make sure that the result of this icode is not on the
2554 stack, since acc is used to compute stack offset */
2555 if (isOperandOnStack(IC_RESULT(uic)))
2558 /* if either one of them in far space then we cannot */
2559 if ((IS_TRUE_SYMOP (IC_LEFT (uic)) &&
2560 isOperandInFarSpace (IC_LEFT (uic))) ||
2561 (IS_TRUE_SYMOP (IC_RIGHT (uic)) &&
2562 isOperandInFarSpace (IC_RIGHT (uic))))
2565 /* if the usage has only one operand then we can */
2566 if (IC_LEFT (uic) == NULL ||
2567 IC_RIGHT (uic) == NULL)
2570 /* make sure this is on the left side if not
2571 a '+' since '+' is commutative */
2572 if (ic->op != '+' &&
2573 IC_LEFT (uic)->key != IC_RESULT (ic)->key)
2576 /* if the other one is not on stack then we can */
2577 if (IC_LEFT (uic)->key == IC_RESULT (ic)->key &&
2578 (IS_ITEMP (IC_RIGHT (uic)) ||
2579 (IS_TRUE_SYMOP (IC_RIGHT (uic)) &&
2580 !OP_SYMBOL (IC_RIGHT (uic))->onStack)))
2583 if (IC_RIGHT (uic)->key == IC_RESULT (ic)->key &&
2584 (IS_ITEMP (IC_LEFT (uic)) ||
2585 (IS_TRUE_SYMOP (IC_LEFT (uic)) &&
2586 !OP_SYMBOL (IC_LEFT (uic))->onStack)))
2592 OP_SYMBOL (IC_RESULT (ic))->accuse = 1;
2597 /*-----------------------------------------------------------------*/
2598 /* packForPush - hueristics to reduce iCode for pushing */
2599 /*-----------------------------------------------------------------*/
2601 packForPush (iCode * ic, eBBlock * ebp)
2606 if ((ic->op != IPUSH && ic->op != SEND) || !IS_ITEMP (IC_LEFT (ic)))
2609 /* must have only definition & one usage */
2610 if (bitVectnBitsOn (OP_DEFS (IC_LEFT (ic))) != 1 ||
2611 bitVectnBitsOn (OP_USES (IC_LEFT (ic))) != 1)
2614 /* find the definition */
2615 if (!(dic = hTabItemWithKey (iCodehTab,
2616 bitVectFirstBit (OP_DEFS (IC_LEFT (ic))))))
2619 if (dic->op != '=' || POINTER_SET (dic))
2622 if (dic->eBBlockNum != ic->eBBlockNum) return ;
2624 /* make sure the right side does not have any definitions
2626 dbv = OP_DEFS(IC_RIGHT(dic));
2627 for (lic = ic; lic && lic != dic ; lic = lic->prev) {
2628 if (bitVectBitValue(dbv,lic->key)) return ;
2630 /* make sure they have the same type */
2631 if (IS_SPEC(operandType(IC_LEFT(ic))))
2633 sym_link *itype=operandType(IC_LEFT(ic));
2634 sym_link *ditype=operandType(IC_RIGHT(dic));
2636 if (SPEC_USIGN(itype)!=SPEC_USIGN(ditype) ||
2637 SPEC_LONG(itype)!=SPEC_LONG(ditype))
2640 /* extend the live range of replaced operand if needed */
2641 if (OP_SYMBOL(IC_RIGHT(dic))->liveTo < OP_SYMBOL(IC_LEFT(ic))->liveTo) {
2642 OP_SYMBOL(IC_RIGHT(dic))->liveTo = OP_SYMBOL(IC_LEFT(ic))->liveTo;
2643 OP_SYMBOL(IC_RIGHT(dic))->clashes =
2644 bitVectUnion(OP_SYMBOL(IC_RIGHT(dic))->clashes,
2645 OP_SYMBOL(IC_LEFT(ic))->clashes);
2647 for (lic = ic; lic && lic != dic; lic = lic->prev)
2649 bitVectUnSetBit (lic->rlive, IC_LEFT (ic)->key);
2650 if (IS_ITEMP (IC_RIGHT (dic)))
2651 bitVectSetBit (lic->rlive, IC_RIGHT (dic)->key);
2653 /* we now we know that it has one & only one def & use
2654 and the that the definition is an assignment */
2655 IC_LEFT (ic) = IC_RIGHT (dic);
2657 remiCodeFromeBBlock (ebp, dic);
2658 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2659 hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
2662 /*-----------------------------------------------------------------*/
2663 /* packRegisters - does some transformations to reduce register */
2665 /*-----------------------------------------------------------------*/
2667 packRegisters (eBBlock * ebp)
2677 /* look for assignments of the form */
2678 /* iTempNN = TRueSym (someoperation) SomeOperand */
2680 /* TrueSym := iTempNN:1 */
2681 for (ic = ebp->sch; ic; ic = ic->next)
2685 /* find assignment of the form TrueSym := iTempNN:1 */
2686 if (ic->op == '=' && !POINTER_SET (ic))
2687 change += packRegsForAssign (ic, ebp);
2694 for (ic = ebp->sch; ic; ic = ic->next)
2697 /* if this is an itemp & result of a address of a true sym
2698 then mark this as rematerialisable */
2699 if (ic->op == ADDRESS_OF &&
2700 IS_ITEMP (IC_RESULT (ic)) &&
2701 IS_TRUE_SYMOP (IC_LEFT (ic)) &&
2702 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1 &&
2703 !OP_SYMBOL (IC_LEFT (ic))->onStack)
2706 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2707 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2708 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2712 /* if this is an itemp & used as a pointer
2713 & assigned to a literal then remat */
2714 if (IS_ASSIGN_ICODE(ic) &&
2715 IS_ITEMP(IC_RESULT(ic)) &&
2716 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1 &&
2717 isOperandLiteral(IC_RIGHT(ic)))
2719 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2720 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2721 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2724 /* if straight assignment then carry remat flag if
2725 this is the only definition */
2726 if (ic->op == '=' &&
2727 !POINTER_SET (ic) &&
2728 IS_SYMOP (IC_RIGHT (ic)) &&
2729 OP_SYMBOL (IC_RIGHT (ic))->remat &&
2730 !IS_CAST_ICODE(OP_SYMBOL (IC_RIGHT (ic))->rematiCode) &&
2731 bitVectnBitsOn (OP_SYMBOL (IC_RESULT (ic))->defs) <= 1)
2734 OP_SYMBOL (IC_RESULT (ic))->remat =
2735 OP_SYMBOL (IC_RIGHT (ic))->remat;
2736 OP_SYMBOL (IC_RESULT (ic))->rematiCode =
2737 OP_SYMBOL (IC_RIGHT (ic))->rematiCode;
2740 /* if cast to a generic pointer & the pointer being
2741 cast is remat, then we can remat this cast as well */
2742 if (ic->op == CAST &&
2743 IS_SYMOP(IC_RIGHT(ic)) &&
2744 !OP_SYMBOL(IC_RESULT(ic))->isreqv &&
2745 OP_SYMBOL(IC_RIGHT(ic))->remat ) {
2746 sym_link *to_type = operandType(IC_LEFT(ic));
2747 sym_link *from_type = operandType(IC_RIGHT(ic));
2748 if (IS_GENPTR(to_type) && IS_PTR(from_type)) {
2749 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2750 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2751 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2755 /* if this is a +/- operation with a rematerizable
2756 then mark this as rematerializable as well */
2757 if ((ic->op == '+' || ic->op == '-') &&
2758 (IS_SYMOP (IC_LEFT (ic)) &&
2759 IS_ITEMP (IC_RESULT (ic)) &&
2760 OP_SYMBOL (IC_LEFT (ic))->remat &&
2761 (!IS_SYMOP (IC_RIGHT (ic)) || !IS_CAST_ICODE(OP_SYMBOL (IC_RIGHT (ic))->rematiCode)) &&
2762 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1 &&
2763 IS_OP_LITERAL (IC_RIGHT (ic))))
2766 //int i = operandLitValue(IC_RIGHT(ic));
2767 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2768 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2769 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2772 /* mark the pointer usages */
2773 if (POINTER_SET (ic) && IS_SYMOP (IC_RESULT (ic)))
2774 OP_SYMBOL (IC_RESULT (ic))->uptr = 1;
2776 if (POINTER_GET (ic) && IS_SYMOP (IC_LEFT (ic)))
2777 OP_SYMBOL (IC_LEFT (ic))->uptr = 1;
2779 if (ic->op == RETURN && IS_SYMOP (IC_LEFT(ic)))
2780 OP_SYMBOL (IC_LEFT (ic))->uptr = 1;
2782 if (ic->op == RECEIVE && ic->argreg == 1 &&
2783 IS_SYMOP (IC_RESULT (ic)) &&
2784 getSize (operandType(IC_RESULT(ic))) <= 3)
2785 OP_SYMBOL (IC_RESULT(ic))->uptr = 1;
2787 if (ic->op == SEND && ic->argreg == 1 &&
2788 IS_SYMOP(IC_LEFT(ic)) &&
2789 getSize (aggrToPtr(operandType(IC_LEFT(ic)),FALSE)) <= 3)
2790 OP_SYMBOL (IC_LEFT(ic))->uptr = 1;
2794 /* if we are using a symbol on the stack
2795 then we should say ds390_ptrRegReq */
2796 if (ic->op == IFX && IS_SYMOP (IC_COND (ic)))
2797 ds390_ptrRegReq += ((OP_SYMBOL (IC_COND (ic))->onStack ? !options.stack10bit : 0) +
2798 OP_SYMBOL (IC_COND (ic))->iaccess);
2799 else if (ic->op == JUMPTABLE && IS_SYMOP (IC_JTCOND (ic)))
2800 ds390_ptrRegReq += ((OP_SYMBOL (IC_JTCOND (ic))->onStack ? !options.stack10bit : 0) +
2801 OP_SYMBOL (IC_JTCOND (ic))->iaccess);
2804 if (IS_SYMOP (IC_LEFT (ic)))
2805 ds390_ptrRegReq += ((OP_SYMBOL (IC_LEFT (ic))->onStack ? !options.stack10bit : 0) +
2806 OP_SYMBOL (IC_LEFT (ic))->iaccess);
2807 if (IS_SYMOP (IC_RIGHT (ic)))
2808 ds390_ptrRegReq += ((OP_SYMBOL (IC_RIGHT (ic))->onStack ? !options.stack10bit : 0) +
2809 OP_SYMBOL (IC_RIGHT (ic))->iaccess);
2810 if (IS_SYMOP (IC_RESULT (ic)))
2811 ds390_ptrRegReq += ((OP_SYMBOL (IC_RESULT (ic))->onStack ? !options.stack10bit : 0) +
2812 OP_SYMBOL (IC_RESULT (ic))->iaccess);
2816 /* if the condition of an if instruction
2817 is defined in the previous instruction and
2818 this is the only usage then
2819 mark the itemp as a conditional */
2820 if ((IS_CONDITIONAL (ic) ||
2821 (IS_BITWISE_OP(ic) && isBitwiseOptimizable (ic))) &&
2822 ic->next && ic->next->op == IFX &&
2823 bitVectnBitsOn (OP_USES(IC_RESULT(ic)))==1 &&
2824 isOperandEqual (IC_RESULT (ic), IC_COND (ic->next)) &&
2825 OP_SYMBOL (IC_RESULT (ic))->liveTo <= ic->next->seq)
2827 OP_SYMBOL (IC_RESULT (ic))->regType = REG_CND;
2831 /* reduce for support function calls */
2832 if (ic->supportRtn || ic->op == '+' || ic->op == '-')
2833 packRegsForSupport (ic, ebp);
2835 /* some cases the redundant moves can
2836 can be eliminated for return statements . Can be elminated for the first SEND */
2837 if ((ic->op == RETURN ||
2838 ((ic->op == SEND || ic->op == RECEIVE)&& ic->argreg == 1)) &&
2839 !isOperandInFarSpace (IC_LEFT (ic)) &&
2842 packRegsDPTRuse (IC_LEFT (ic));
2845 if (ic->op == CALL) {
2846 sym_link *ftype = operandType(IC_LEFT(ic));
2847 if (getSize(operandType(IC_RESULT(ic))) <= 4 &&
2848 !IFFUNC_ISBUILTIN(ftype)) {
2849 packRegsDPTRuse (IC_RESULT (ic));
2853 /* if pointer set & left has a size more than
2854 one and right is not in far space */
2855 if (POINTER_SET (ic) &&
2856 !isOperandInFarSpace (IC_RIGHT (ic)) &&
2857 IS_SYMOP (IC_RESULT (ic)) &&
2858 !OP_SYMBOL (IC_RESULT (ic))->remat &&
2859 !IS_OP_RUONLY (IC_RIGHT (ic)) &&
2860 getSize (aggrToPtr (operandType (IC_RESULT (ic)), FALSE)) > 1) {
2862 packRegsDPTRuse (IC_RESULT (ic));
2865 /* if pointer get */
2866 if (POINTER_GET (ic) &&
2867 !isOperandInFarSpace (IC_RESULT (ic)) &&
2868 IS_SYMOP (IC_LEFT (ic)) &&
2869 !OP_SYMBOL (IC_LEFT (ic))->remat &&
2870 !IS_OP_RUONLY (IC_RESULT (ic)) &&
2871 getSize (aggrToPtr (operandType (IC_LEFT (ic)), FALSE)) > 1) {
2873 packRegsDPTRuse (IC_LEFT (ic));
2876 /* if this is cast for intergral promotion then
2877 check if only use of the definition of the
2878 operand being casted/ if yes then replace
2879 the result of that arithmetic operation with
2880 this result and get rid of the cast */
2883 sym_link *fromType = operandType (IC_RIGHT (ic));
2884 sym_link *toType = operandType (IC_LEFT (ic));
2886 if (IS_INTEGRAL (fromType) && IS_INTEGRAL (toType) &&
2887 getSize (fromType) != getSize (toType) &&
2888 SPEC_USIGN (fromType) == SPEC_USIGN (toType))
2891 iCode *dic = packRegsDPTRuse (IC_RIGHT (ic));
2894 if (IS_ARITHMETIC_OP (dic))
2896 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2897 IC_RESULT (dic) = IC_RESULT (ic);
2898 remiCodeFromeBBlock (ebp, ic);
2899 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
2900 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
2901 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
2905 OP_SYMBOL (IC_RIGHT (ic))->ruonly = 0;
2911 /* if the type from and type to are the same
2912 then if this is the only use then packit */
2913 if (compareType (operandType (IC_RIGHT (ic)),
2914 operandType (IC_LEFT (ic))) == 1)
2916 iCode *dic = packRegsDPTRuse (IC_RIGHT (ic));
2919 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
2920 IC_RESULT (dic) = IC_RESULT (ic);
2921 remiCodeFromeBBlock (ebp, ic);
2922 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
2923 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
2924 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
2932 iTempNN := (some variable in farspace) V1
2937 if (ic->op == IPUSH || ic->op == SEND)
2939 packForPush (ic, ebp);
2943 /* pack registers for accumulator use, when the
2944 result of an arithmetic or bit wise operation
2945 has only one use, that use is immediately following
2946 the defintion and the using iCode has only one
2947 operand or has two operands but one is literal &
2948 the result of that operation is not on stack then
2949 we can leave the result of this operation in acc:b
2951 if ((IS_ARITHMETIC_OP (ic)
2952 || IS_CONDITIONAL(ic)
2953 || IS_BITWISE_OP (ic)
2954 || ic->op == LEFT_OP || ic->op == RIGHT_OP
2955 || (ic->op == ADDRESS_OF && isOperandOnStack (IC_LEFT (ic)))
2957 IS_ITEMP (IC_RESULT (ic)) &&
2958 getSize (operandType (IC_RESULT (ic))) <= 2)
2960 packRegsForAccUse (ic);
2965 /*-----------------------------------------------------------------*/
2966 /* assignRegisters - assigns registers to each live range as need */
2967 /*-----------------------------------------------------------------*/
2969 ds390_assignRegisters (eBBlock ** ebbs, int count)
2974 setToNull ((void *) &_G.funcrUsed);
2975 setToNull ((void *) &_G.regAssigned);
2976 setToNull ((void *) &_G.totRegAssigned);
2977 setToNull ((void *) &_G.funcrUsed);
2978 ds390_ptrRegReq = _G.stackExtend = _G.dataExtend = 0;
2980 if (options.model != MODEL_FLAT24) options.stack10bit = 0;
2981 /* change assignments this will remove some
2982 live ranges reducing some register pressure */
2983 for (i = 0; i < count; i++)
2984 packRegisters (ebbs[i]);
2986 if (options.dump_pack)
2987 dumpEbbsToFileExt (DUMP_PACK, ebbs, count);
2989 /* first determine for each live range the number of
2990 registers & the type of registers required for each */
2993 /* and serially allocate registers */
2994 serialRegAssign (ebbs, count);
3001 /* if stack was extended then tell the user */
3004 /* werror(W_TOOMANY_SPILS,"stack", */
3005 /* _G.stackExtend,currFunc->name,""); */
3011 /* werror(W_TOOMANY_SPILS,"data space", */
3012 /* _G.dataExtend,currFunc->name,""); */
3016 /* after that create the register mask
3017 for each of the instruction */
3018 createRegMask (ebbs, count);
3020 /* redo that offsets for stacked automatic variables */
3021 redoStackOffsets ();
3023 if (options.dump_rassgn) {
3024 dumpEbbsToFileExt (DUMP_RASSGN, ebbs, count);
3025 dumpLiveRanges (DUMP_LRANGE, liveRanges);
3028 /* do the overlaysegment stuff SDCCmem.c */
3029 doOverlays (ebbs, count);
3031 /* now get back the chain */
3032 ic = iCodeLabelOptimize (iCodeFromeBBlock (ebbs, count));
3037 /* free up any _G.stackSpil locations allocated */
3038 applyToSet (_G.stackSpil, deallocStackSpil);
3040 setToNull ((void **) &_G.stackSpil);
3041 setToNull ((void **) &_G.spiltSet);
3042 /* mark all registers as free */