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 */
1341 /* if it shares registers with operands make sure
1342 that they are in the same position */
1343 if (!POINTER_SET(ic) && !POINTER_GET(ic))
1345 if (IC_LEFT (ic) && IS_SYMOP (IC_LEFT (ic)) &&
1346 OP_SYMBOL (IC_LEFT (ic))->nRegs)
1348 positionRegs (OP_SYMBOL (IC_RESULT (ic)),
1349 OP_SYMBOL (IC_LEFT (ic)));
1351 /* do the same for the right operand */
1352 if (IC_RIGHT (ic) && IS_SYMOP (IC_RIGHT (ic)) &&
1353 OP_SYMBOL (IC_RIGHT (ic))->nRegs)
1355 positionRegs (OP_SYMBOL (IC_RESULT (ic)),
1356 OP_SYMBOL (IC_RIGHT (ic)));
1368 reassignUnusedLRs(unusedLRs);
1372 /*-----------------------------------------------------------------*/
1373 /* fillGaps - Try to fill in the Gaps left by Pass1 */
1374 /*-----------------------------------------------------------------*/
1375 static void fillGaps()
1379 int loop = 0, change;
1381 if (getenv("DISABLE_FILL_GAPS")) return;
1383 /* First try to do DPTRuse once more since now we know what got into
1386 while (loop++ < 10) {
1389 for (sym = hTabFirstItem(liveRanges,&key) ; sym ;
1390 sym = hTabNextItem(liveRanges,&key)) {
1391 int size = getSize(sym->type);
1393 if (sym->liveFrom == sym->liveTo) continue;
1395 if (sym->uptr && sym->dptr==0 && !sym->ruonly &&
1396 size < 4 && size > 1) {
1398 if (packRegsDPTRuse(operandFromSymbol(sym))) {
1400 /* if this was ssigned to registers then */
1401 if (bitVectBitValue(_G.totRegAssigned,sym->key)) {
1402 /* take it out of the register assigned set */
1403 bitVectUnSetBit(_G.totRegAssigned,sym->key);
1404 } else if (sym->usl.spillLoc) {
1405 sym->usl.spillLoc->allocreq--;
1406 sym->usl.spillLoc = NULL;
1410 sym->isspilt = sym->spillA = 0;
1414 /* try assigning other dptrs */
1415 if (sym->dptr == 0 && packRegsDPTRnuse(operandFromSymbol(sym),1) && !getenv("DPTRnDISABLE")) {
1416 /* if this was ssigned to registers then */
1417 if (bitVectBitValue(_G.totRegAssigned,sym->key)) {
1418 /* take it out of the register assigned set */
1419 bitVectUnSetBit(_G.totRegAssigned,sym->key);
1420 } else if (sym->usl.spillLoc) {
1421 sym->usl.spillLoc->allocreq--;
1422 sym->usl.spillLoc = NULL;
1425 sym->isspilt = sym->spillA = 0;
1430 /* look for livernages that was spilt by the allocator */
1431 for (sym = hTabFirstItem(liveRanges,&key) ; sym ;
1432 sym = hTabNextItem(liveRanges,&key)) {
1437 if (!sym->spillA || !sym->clashes || sym->remat) continue ;
1438 if (!sym->uses || !sym->defs) continue ;
1439 /* find the liveRanges this one clashes with, that are
1440 still assigned to registers & mark the registers as used*/
1441 for ( i = 0 ; i < sym->clashes->size ; i ++) {
1445 if (bitVectBitValue(sym->clashes,i) == 0 || /* those that clash with this */
1446 bitVectBitValue(_G.totRegAssigned,i) == 0) /* and are still assigned to registers */
1449 clr = hTabItemWithKey(liveRanges,i);
1452 /* mark these registers as used */
1453 for (k = 0 ; k < clr->nRegs ; k++ )
1454 useReg(clr->regs[k]);
1457 if (willCauseSpill(sym->nRegs,sym->regType)) {
1458 /* NOPE :( clear all registers & and continue */
1463 /* THERE IS HOPE !!!! */
1464 for (i=0; i < sym->nRegs ; i++ ) {
1465 if (sym->regType == REG_PTR)
1466 sym->regs[i] = getRegPtrNoSpil ();
1468 sym->regs[i] = getRegGprNoSpil ();
1471 /* for all its definitions & uses check if the registers
1472 allocated needs positioning NOTE: we can position
1473 only ONCE if more than One positioning required
1476 for (i = 0 ; i < sym->defs->size ; i++ ) {
1477 if (bitVectBitValue(sym->defs,i)) {
1479 if (!(ic = hTabItemWithKey(iCodehTab,i))) continue ;
1480 if (SKIP_IC(ic)) continue;
1481 assert(isSymbolEqual(sym,OP_SYMBOL(IC_RESULT(ic)))); /* just making sure */
1482 /* if left is assigned to registers */
1483 if (IS_SYMOP(IC_LEFT(ic)) &&
1484 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_LEFT(ic))->key)) {
1485 pdone += (positionRegs(sym,OP_SYMBOL(IC_LEFT(ic)))>0);
1487 if (IS_SYMOP(IC_RIGHT(ic)) &&
1488 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_RIGHT(ic))->key)) {
1489 pdone += (positionRegs(sym,OP_SYMBOL(IC_RIGHT(ic)))>0);
1491 if (pdone > 1) break;
1494 for (i = 0 ; i < sym->uses->size ; i++ ) {
1495 if (bitVectBitValue(sym->uses,i)) {
1497 if (!(ic = hTabItemWithKey(iCodehTab,i))) continue ;
1498 if (SKIP_IC(ic)) continue;
1499 if (POINTER_SET(ic) || POINTER_GET(ic)) continue ;
1501 /* if result is assigned to registers */
1502 if (IS_SYMOP(IC_RESULT(ic)) &&
1503 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_RESULT(ic))->key)) {
1504 pdone += (positionRegs(sym,OP_SYMBOL(IC_RESULT(ic)))>0);
1506 if (pdone > 1) break;
1509 /* had to position more than once GIVE UP */
1511 /* UNDO all the changes we made to try this */
1513 for (i=0; i < sym->nRegs ; i++ ) {
1514 sym->regs[i] = NULL;
1517 D (fprintf (stderr, "Fill Gap gave up due to positioning for "
1518 "%s in function %s\n",
1519 sym->name, currFunc ? currFunc->name : "UNKNOWN"));
1522 D (fprintf (stderr, "FILLED GAP for %s in function %s\n",
1523 sym->name, currFunc ? currFunc->name : "UNKNOWN"));
1524 _G.totRegAssigned = bitVectSetBit(_G.totRegAssigned,sym->key);
1525 sym->isspilt = sym->spillA = 0 ;
1526 sym->usl.spillLoc->allocreq--;
1527 sym->usl.spillLoc = NULL;
1535 /*-----------------------------------------------------------------*/
1536 /* rUmaskForOp :- returns register mask for an operand */
1537 /*-----------------------------------------------------------------*/
1539 ds390_rUmaskForOp (operand * op)
1545 /* only temporaries are assigned registers */
1549 sym = OP_SYMBOL (op);
1551 /* if spilt or no registers assigned to it
1553 if (sym->isspilt || !sym->nRegs)
1556 rumask = newBitVect (ds390_nRegs);
1558 for (j = 0; j < sym->nRegs; j++)
1560 rumask = bitVectSetBit (rumask,
1561 sym->regs[j]->rIdx);
1567 /*-----------------------------------------------------------------*/
1568 /* regsUsedIniCode :- returns bit vector of registers used in iCode */
1569 /*-----------------------------------------------------------------*/
1571 regsUsedIniCode (iCode * ic)
1573 bitVect *rmask = newBitVect (ds390_nRegs);
1575 /* do the special cases first */
1578 rmask = bitVectUnion (rmask,
1579 ds390_rUmaskForOp (IC_COND (ic)));
1583 /* for the jumptable */
1584 if (ic->op == JUMPTABLE)
1586 rmask = bitVectUnion (rmask,
1587 ds390_rUmaskForOp (IC_JTCOND (ic)));
1592 /* of all other cases */
1594 rmask = bitVectUnion (rmask,
1595 ds390_rUmaskForOp (IC_LEFT (ic)));
1599 rmask = bitVectUnion (rmask,
1600 ds390_rUmaskForOp (IC_RIGHT (ic)));
1603 rmask = bitVectUnion (rmask,
1604 ds390_rUmaskForOp (IC_RESULT (ic)));
1610 /*-----------------------------------------------------------------*/
1611 /* createRegMask - for each instruction will determine the regsUsed */
1612 /*-----------------------------------------------------------------*/
1614 createRegMask (eBBlock ** ebbs, int count)
1618 /* for all blocks */
1619 for (i = 0; i < count; i++)
1623 if (ebbs[i]->noPath &&
1624 (ebbs[i]->entryLabel != entryLabel &&
1625 ebbs[i]->entryLabel != returnLabel))
1628 /* for all instructions */
1629 for (ic = ebbs[i]->sch; ic; ic = ic->next)
1634 if (SKIP_IC2 (ic) || !ic->rlive)
1637 /* first mark the registers used in this
1639 ic->rUsed = regsUsedIniCode (ic);
1640 _G.funcrUsed = bitVectUnion (_G.funcrUsed, ic->rUsed);
1642 /* now create the register mask for those
1643 registers that are in use : this is a
1644 super set of ic->rUsed */
1645 ic->rMask = newBitVect (ds390_nRegs + 1);
1647 /* for all live Ranges alive at this point */
1648 for (j = 1; j < ic->rlive->size; j++)
1653 /* if not alive then continue */
1654 if (!bitVectBitValue (ic->rlive, j))
1657 /* find the live range we are interested in */
1658 if (!(sym = hTabItemWithKey (liveRanges, j)))
1660 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
1661 "createRegMask cannot find live range");
1665 /* special case for ruonly */
1666 if (sym->ruonly && sym->liveFrom != sym->liveTo) {
1667 int size = getSize(sym->type);
1669 for (k = 0 ; k < size; k++ )
1670 ic->rMask = bitVectSetBit (ic->rMask, j++);
1673 /* if no register assigned to it */
1674 if (!sym->nRegs || sym->isspilt)
1677 /* for all the registers allocated to it */
1678 for (k = 0; k < sym->nRegs; k++)
1681 bitVectSetBit (ic->rMask, sym->regs[k]->rIdx);
1687 /*-----------------------------------------------------------------*/
1688 /* rematStr - returns the rematerialized string for a remat var */
1689 /*-----------------------------------------------------------------*/
1691 rematStr (symbol * sym)
1694 iCode *ic = sym->rematiCode;
1701 /* if plus or minus print the right hand side */
1702 if (ic->op == '+' || ic->op == '-')
1704 SNPRINTF (s, sizeof(buffer) - strlen(buffer),
1705 "0x%04x %c ", (int) operandLitValue (IC_RIGHT (ic)),
1708 ic = OP_SYMBOL (IC_LEFT (ic))->rematiCode;
1711 /* cast then continue */
1712 if (IS_CAST_ICODE(ic)) {
1713 ic = OP_SYMBOL (IC_RIGHT (ic))->rematiCode;
1716 /* we reached the end */
1717 SNPRINTF (s, sizeof(buffer) - strlen(buffer),
1718 "%s", OP_SYMBOL (IC_LEFT (ic))->rname);
1725 /*-----------------------------------------------------------------*/
1726 /* regTypeNum - computes the type & number of registers required */
1727 /*-----------------------------------------------------------------*/
1735 /* for each live range do */
1736 for (sym = hTabFirstItem (liveRanges, &k); sym;
1737 sym = hTabNextItem (liveRanges, &k))
1740 /* if used zero times then no registers needed */
1741 if ((sym->liveTo - sym->liveFrom) == 0)
1745 /* if the live range is a temporary */
1749 /* if the type is marked as a conditional */
1750 if (sym->regType == REG_CND)
1753 /* if used in return only then we don't
1755 if (sym->ruonly || sym->accuse)
1757 if (IS_AGGREGATE (sym->type) || sym->isptr)
1758 sym->type = aggrToPtr (sym->type, FALSE);
1762 /* if the symbol has only one definition &
1763 that definition is a get_pointer */
1764 if (bitVectnBitsOn (sym->defs) == 1 &&
1765 (ic = hTabItemWithKey (iCodehTab,
1766 bitVectFirstBit (sym->defs))) &&
1769 !IS_BITVAR (sym->etype))
1771 /* and that pointer is remat in data space */
1772 if (IS_SYMOP (IC_LEFT (ic)) &&
1773 OP_SYMBOL (IC_LEFT (ic))->remat &&
1774 !IS_CAST_ICODE(OP_SYMBOL (IC_LEFT (ic))->rematiCode) &&
1775 DCL_TYPE (aggrToPtr (operandType(IC_LEFT(ic)), FALSE)) == POINTER)
1778 /* create a psuedo symbol & force a spil */
1779 symbol *psym = newSymbol (rematStr (OP_SYMBOL (IC_LEFT (ic))), 1);
1780 psym->type = sym->type;
1781 psym->etype = sym->etype;
1782 strncpyz (psym->rname, psym->name, sizeof(psym->rname));
1784 sym->usl.spillLoc = psym;
1788 /* if in data space or idata space then try to
1789 allocate pointer register */
1793 /* if not then we require registers */
1794 sym->nRegs = ((IS_AGGREGATE (sym->type) || sym->isptr) ?
1795 getSize (sym->type = aggrToPtr (sym->type, FALSE)) :
1796 getSize (sym->type));
1800 fprintf (stderr, "allocated more than 4 or 0 registers for type ");
1801 printTypeChain (sym->type, stderr);
1802 fprintf (stderr, "\n");
1805 /* determine the type of register required */
1806 if (sym->nRegs == 1 &&
1807 IS_PTR (sym->type) &&
1809 sym->regType = REG_PTR;
1811 sym->regType = REG_GPR;
1815 /* for the first run we don't provide */
1816 /* registers for true symbols we will */
1817 /* see how things go */
1823 /*-----------------------------------------------------------------*/
1824 /* freeAllRegs - mark all registers as free */
1825 /*-----------------------------------------------------------------*/
1831 for (i = 0; i < ds390_nRegs; i++)
1832 regs390[i].isFree = 1;
1835 /*-----------------------------------------------------------------*/
1836 /* deallocStackSpil - this will set the stack pointer back */
1837 /*-----------------------------------------------------------------*/
1839 DEFSETFUNC (deallocStackSpil)
1847 /*-----------------------------------------------------------------*/
1848 /* farSpacePackable - returns the packable icode for far variables */
1849 /*-----------------------------------------------------------------*/
1851 farSpacePackable (iCode * ic)
1855 /* go thru till we find a definition for the
1856 symbol on the right */
1857 for (dic = ic->prev; dic; dic = dic->prev)
1860 /* if the definition is a call then no */
1861 if ((dic->op == CALL || dic->op == PCALL) &&
1862 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1867 /* if shift by unknown amount then not */
1868 if ((dic->op == LEFT_OP || dic->op == RIGHT_OP) &&
1869 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1872 /* if pointer get and size > 1 */
1873 if (POINTER_GET (dic) &&
1874 getSize (aggrToPtr (operandType (IC_LEFT (dic)), FALSE)) > 1)
1877 if (POINTER_SET (dic) &&
1878 getSize (aggrToPtr (operandType (IC_RESULT (dic)), FALSE)) > 1)
1881 /* if any three is a true symbol in far space */
1882 if (IC_RESULT (dic) &&
1883 IS_TRUE_SYMOP (IC_RESULT (dic)) &&
1884 isOperandInFarSpace (IC_RESULT (dic)))
1887 if (IC_RIGHT (dic) &&
1888 IS_TRUE_SYMOP (IC_RIGHT (dic)) &&
1889 isOperandInFarSpace (IC_RIGHT (dic)) &&
1890 !isOperandEqual (IC_RIGHT (dic), IC_RESULT (ic)))
1893 if (IC_LEFT (dic) &&
1894 IS_TRUE_SYMOP (IC_LEFT (dic)) &&
1895 isOperandInFarSpace (IC_LEFT (dic)) &&
1896 !isOperandEqual (IC_LEFT (dic), IC_RESULT (ic)))
1899 if (isOperandEqual (IC_RIGHT (ic), IC_RESULT (dic)))
1901 if ((dic->op == LEFT_OP ||
1902 dic->op == RIGHT_OP ||
1904 IS_OP_LITERAL (IC_RIGHT (dic)))
1914 /*-----------------------------------------------------------------*/
1915 /* packRegsForAssign - register reduction for assignment */
1916 /*-----------------------------------------------------------------*/
1918 packRegsForAssign (iCode * ic, eBBlock * ebp)
1922 if (!IS_ITEMP (IC_RIGHT (ic)) ||
1923 OP_SYMBOL (IC_RIGHT (ic))->isind ||
1924 OP_LIVETO (IC_RIGHT (ic)) > ic->seq)
1929 /* if the true symbol is defined in far space or on stack
1930 then we should not since this will increase register pressure */
1932 if (isOperandInFarSpace (IC_RESULT (ic)))
1934 if ((dic = farSpacePackable (ic)))
1940 if (isOperandInFarSpace(IC_RESULT(ic)) && !farSpacePackable(ic)) {
1945 /* find the definition of iTempNN scanning backwards if we find a
1946 a use of the true symbol in before we find the definition then
1948 for (dic = ic->prev; dic; dic = dic->prev)
1950 /* if there is a function call then don't pack it */
1951 if ((dic->op == CALL || dic->op == PCALL))
1960 if (IS_TRUE_SYMOP (IC_RESULT (dic)) &&
1961 IS_OP_VOLATILE (IC_RESULT (dic)))
1967 if (IS_SYMOP (IC_RESULT (dic)) &&
1968 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1970 if (POINTER_SET (dic))
1976 if (IS_SYMOP (IC_RIGHT (dic)) &&
1977 (IC_RIGHT (dic)->key == IC_RESULT (ic)->key ||
1978 IC_RIGHT (dic)->key == IC_RIGHT (ic)->key))
1984 if (IS_SYMOP (IC_LEFT (dic)) &&
1985 (IC_LEFT (dic)->key == IC_RESULT (ic)->key ||
1986 IC_LEFT (dic)->key == IC_RIGHT (ic)->key))
1992 if (POINTER_SET (dic) &&
1993 IC_RESULT (dic)->key == IC_RESULT (ic)->key)
2001 return 0; /* did not find */
2003 /* if the result is on stack or iaccess then it must be
2004 the same atleast one of the operands */
2005 if (OP_SYMBOL (IC_RESULT (ic))->onStack ||
2006 OP_SYMBOL (IC_RESULT (ic))->iaccess)
2009 /* the operation has only one symbol
2010 operator then we can pack */
2011 if ((IC_LEFT (dic) && !IS_SYMOP (IC_LEFT (dic))) ||
2012 (IC_RIGHT (dic) && !IS_SYMOP (IC_RIGHT (dic))))
2015 if (!((IC_LEFT (dic) &&
2016 IC_RESULT (ic)->key == IC_LEFT (dic)->key) ||
2018 IC_RESULT (ic)->key == IC_RIGHT (dic)->key)))
2022 /* found the definition */
2023 /* replace the result with the result of */
2024 /* this assignment and remove this assignment */
2025 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2027 IC_RESULT (dic) = IC_RESULT (ic);
2029 if (IS_ITEMP (IC_RESULT (dic)) && OP_SYMBOL (IC_RESULT (dic))->liveFrom > dic->seq)
2031 OP_SYMBOL (IC_RESULT (dic))->liveFrom = dic->seq;
2033 /* delete from liverange table also
2034 delete from all the points inbetween and the new
2036 for (sic = dic; sic != ic; sic = sic->next)
2038 bitVectUnSetBit (sic->rlive, IC_RESULT (ic)->key);
2039 if (IS_ITEMP (IC_RESULT (dic)))
2040 bitVectSetBit (sic->rlive, IC_RESULT (dic)->key);
2043 remiCodeFromeBBlock (ebp, ic);
2044 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
2045 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
2046 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
2051 /*-----------------------------------------------------------------*/
2052 /* findAssignToSym : scanning backwards looks for first assig found */
2053 /*-----------------------------------------------------------------*/
2055 findAssignToSym (operand * op, iCode * ic)
2059 for (dic = ic->prev; dic; dic = dic->prev)
2062 /* if definition by assignment */
2063 if (dic->op == '=' &&
2064 !POINTER_SET (dic) &&
2065 IC_RESULT (dic)->key == op->key
2066 /* && IS_TRUE_SYMOP(IC_RIGHT(dic)) */
2070 /* we are interested only if defined in far space */
2071 /* or in stack space in case of + & - */
2073 /* if assigned to a non-symbol then return
2075 if (!IS_SYMOP (IC_RIGHT (dic)))
2078 /* if the symbol is in far space then
2080 if (isOperandInFarSpace (IC_RIGHT (dic)))
2083 /* for + & - operations make sure that
2084 if it is on the stack it is the same
2085 as one of the three operands */
2086 if ((ic->op == '+' || ic->op == '-') &&
2087 OP_SYMBOL (IC_RIGHT (dic))->onStack)
2090 if (IC_RESULT (ic)->key != IC_RIGHT (dic)->key &&
2091 IC_LEFT (ic)->key != IC_RIGHT (dic)->key &&
2092 IC_RIGHT (ic)->key != IC_RIGHT (dic)->key)
2100 /* if we find an usage then we cannot delete it */
2101 if (IC_LEFT (dic) && IC_LEFT (dic)->key == op->key)
2104 if (IC_RIGHT (dic) && IC_RIGHT (dic)->key == op->key)
2107 if (POINTER_SET (dic) && IC_RESULT (dic)->key == op->key)
2111 /* now make sure that the right side of dic
2112 is not defined between ic & dic */
2115 iCode *sic = dic->next;
2117 for (; sic != ic; sic = sic->next)
2118 if (IC_RESULT (sic) &&
2119 IC_RESULT (sic)->key == IC_RIGHT (dic)->key)
2128 /*-----------------------------------------------------------------*/
2129 /* packRegsForSupport :- reduce some registers for support calls */
2130 /*-----------------------------------------------------------------*/
2132 packRegsForSupport (iCode * ic, eBBlock * ebp)
2136 /* for the left & right operand :- look to see if the
2137 left was assigned a true symbol in far space in that
2138 case replace them */
2139 if (IS_ITEMP (IC_LEFT (ic)) &&
2140 OP_SYMBOL (IC_LEFT (ic))->liveTo <= ic->seq)
2142 iCode *dic = findAssignToSym (IC_LEFT (ic), ic);
2148 /* found it we need to remove it from the
2150 for (sic = dic; sic != ic; sic = sic->next) {
2151 bitVectUnSetBit (sic->rlive, IC_LEFT (ic)->key);
2152 sic->rlive = bitVectSetBit (sic->rlive, IC_RIGHT (dic)->key);
2155 wassert(IS_SYMOP(IC_LEFT (ic)));
2156 wassert(IS_SYMOP(IC_RIGHT (dic)));
2157 IC_LEFT (ic)->operand.symOperand =
2158 IC_RIGHT (dic)->operand.symOperand;
2159 OP_SYMBOL(IC_LEFT(ic))->liveTo = ic->seq;
2160 IC_LEFT (ic)->key = IC_RIGHT (dic)->operand.symOperand->key;
2161 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2162 remiCodeFromeBBlock (ebp, dic);
2163 hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
2167 /* do the same for the right operand */
2170 IS_ITEMP (IC_RIGHT (ic)) &&
2171 OP_SYMBOL (IC_RIGHT (ic))->liveTo <= ic->seq)
2173 iCode *dic = findAssignToSym (IC_RIGHT (ic), ic);
2179 /* if this is a subtraction & the result
2180 is a true symbol in far space then don't pack */
2181 if (ic->op == '-' && IS_TRUE_SYMOP (IC_RESULT (dic)))
2183 sym_link *etype = getSpec (operandType (IC_RESULT (dic)));
2184 if (IN_FARSPACE (SPEC_OCLS (etype)))
2187 /* found it we need to remove it from the
2189 for (sic = dic; sic != ic; sic = sic->next) {
2190 bitVectUnSetBit (sic->rlive, IC_RIGHT (ic)->key);
2191 sic->rlive = bitVectSetBit (sic->rlive, IC_RIGHT (dic)->key);
2194 wassert(IS_SYMOP(IC_RIGHT (ic)));
2195 wassert(IS_SYMOP(IC_RIGHT (dic)));
2196 IC_RIGHT (ic)->operand.symOperand =
2197 IC_RIGHT (dic)->operand.symOperand;
2198 IC_RIGHT (ic)->key = IC_RIGHT (dic)->operand.symOperand->key;
2199 OP_SYMBOL(IC_RIGHT(ic))->liveTo = ic->seq;
2200 remiCodeFromeBBlock (ebp, dic);
2201 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2202 hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
2209 #define IS_OP_RUONLY(x) (x && IS_SYMOP(x) && OP_SYMBOL(x)->ruonly)
2212 /*-----------------------------------------------------------------*/
2213 /* packRegsDPTRnuse - color live ranges that can go into extra DPTRS */
2214 /*-----------------------------------------------------------------*/
2215 static int packRegsDPTRnuse( operand *op , int dptr)
2220 if (!IS_SYMOP(op) || !IS_ITEMP(op)) return 0;
2221 if (OP_SYMBOL(op)->remat || OP_SYMBOL(op)->ruonly || OP_SYMBOL(op)->dptr)
2224 /* first check if any overlapping liverange has already been
2225 assigned to this DPTR */
2226 if (OP_SYMBOL(op)->clashes) {
2227 for (i = 0 ; i < OP_SYMBOL(op)->clashes->size ; i++ ) {
2229 if (bitVectBitValue(OP_SYMBOL(op)->clashes,i)) {
2230 sym = hTabItemWithKey(liveRanges,i);
2231 if (sym->dptr == dptr) return 0;
2236 /* future for more dptrs */
2238 OP_SYMBOL(op)->dptr = dptr;
2242 /* DPTR1 is special since it is also used as a scratch by the backend .
2243 so we walk thru the entire live range of this operand and make sure
2244 DPTR1 will not be used by the backed . The logic here is to find out if
2245 more than one operand in an icode is in far space then we give up : we
2246 don't keep it live across functions for now
2249 ic = hTabFirstItemWK(iCodeSeqhTab,OP_SYMBOL(op)->liveFrom);
2250 for (; ic && ic->seq <= OP_SYMBOL(op)->liveTo;
2251 ic = hTabNextItem(iCodeSeqhTab,&key)) {
2254 if (ic->op == CALL || ic->op == PCALL) return 0;
2256 /* single operand icode are ok */
2257 if (ic->op == IFX || ic->op == IPUSH)
2260 if (ic->op == SEND ) {
2261 if (ic->argreg != 1 ) return 0;
2264 /* two special cases first */
2265 if (POINTER_GET(ic) && !isOperandEqual(IC_LEFT(ic),op) && /* pointer get */
2266 !OP_SYMBOL(IC_LEFT(ic))->ruonly && /* with result in far space */
2267 (isOperandInFarSpace(IC_RESULT(ic)) &&
2268 !isOperandInReg(IC_RESULT(ic)))) {
2272 if (POINTER_SET(ic) && !isOperandEqual(IC_RESULT(ic),op) && /* pointer set */
2273 !OP_SYMBOL(IC_RESULT(ic))->ruonly && /* with right in far space */
2274 (isOperandInFarSpace(IC_RIGHT(ic)) &&
2275 !isOperandInReg(IC_RIGHT(ic)))) {
2279 if (IC_RESULT(ic) && IS_SYMOP(IC_RESULT(ic)) && /* if symbol operand */
2280 !isOperandEqual(IC_RESULT(ic),op) && /* not the same as this */
2281 ((isOperandInFarSpace(IC_RESULT(ic)) || /* in farspace or */
2282 OP_SYMBOL(IC_RESULT(ic))->onStack) && /* on the stack */
2283 !isOperandInReg(IC_RESULT(ic)))) { /* and not in register */
2287 if (IC_LEFT(ic) && IS_SYMOP(IC_LEFT(ic)) && /* if symbol operand */
2288 !isOperandEqual(IC_LEFT(ic),op) && /* not the same as this */
2289 ((isOperandInFarSpace(IC_LEFT(ic)) || /* in farspace or */
2290 OP_SYMBOL(IC_LEFT(ic))->onStack) && /* on the stack */
2291 !isOperandInReg(IC_LEFT(ic)))) { /* and not in register */
2294 /* same for right */
2295 if (IC_RIGHT(ic) && IS_SYMOP(IC_RIGHT(ic)) && /* if symbol operand */
2296 !isOperandEqual(IC_RIGHT(ic),op) && /* not the same as this */
2297 ((isOperandInFarSpace(IC_RIGHT(ic)) || /* in farspace or */
2298 OP_SYMBOL(IC_RIGHT(ic))->onStack) && /* on the stack */
2299 !isOperandInReg(IC_RIGHT(ic)))) { /* and not in register */
2303 // Check that no other ops in this range have been assigned to dptr1.
2304 // I don't understand why this is not caught by the first check, above.
2305 // But it isn't always, see bug 769624.
2306 if (IC_RESULT(ic) && IS_SYMOP(IC_RESULT(ic)) &&
2307 (OP_SYMBOL(IC_RESULT(ic))->dptr == 1))
2309 //fprintf(stderr, "dptr1 already in use in live range #1\n");
2313 if (IC_LEFT(ic) && IS_SYMOP(IC_LEFT(ic)) &&
2314 (OP_SYMBOL(IC_LEFT(ic))->dptr == 1))
2316 //fprintf(stderr, "dptr1 already in use in live range # 2\n");
2320 if (IC_RIGHT(ic) && IS_SYMOP(IC_RIGHT(ic)) &&
2321 (OP_SYMBOL(IC_RIGHT(ic))->dptr == 1))
2323 //fprintf(stderr, "dptr1 already in use in live range # 3\n");
2327 if (nfs && IC_RESULT(ic) && IS_SYMOP(IC_RESULT(ic)) &&
2328 OP_SYMBOL(IC_RESULT(ic))->ruonly) return 0;
2330 if (nfs > 1) return 0;
2332 OP_SYMBOL(op)->dptr = dptr;
2336 /*-----------------------------------------------------------------*/
2337 /* packRegsDPTRuse : - will reduce some registers for single Use */
2338 /*-----------------------------------------------------------------*/
2340 packRegsDPTRuse (operand * op)
2342 /* go thru entire liveRange of this variable & check for
2343 other possible usage of DPTR , if we don't find it the
2344 assign this to DPTR (ruonly)
2349 sym_link *type, *etype;
2351 if (!IS_SYMOP(op) || !IS_ITEMP(op)) return NULL;
2352 if (OP_SYMBOL(op)->remat || OP_SYMBOL(op)->ruonly) return NULL;
2354 /* first check if any overlapping liverange has already been
2356 if (OP_SYMBOL(op)->clashes) {
2357 for (i = 0 ; i < OP_SYMBOL(op)->clashes->size ; i++ ) {
2358 if (bitVectBitValue(OP_SYMBOL(op)->clashes,i)) {
2359 sym = hTabItemWithKey(liveRanges,i);
2360 if (sym->ruonly) return NULL ;
2365 /* no then go thru this guys live range */
2366 dic = ic = hTabFirstItemWK(iCodeSeqhTab,OP_SYMBOL(op)->liveFrom);
2367 for (; ic && ic->seq <= OP_SYMBOL(op)->liveTo;
2368 ic = hTabNextItem(iCodeSeqhTab,&key)) {
2370 if (SKIP_IC3(ic)) continue;
2372 /* if PCALL cannot be sure give up */
2373 if (ic->op == PCALL) return NULL;
2375 /* if SEND & not the first parameter then giveup */
2376 if (ic->op == SEND && ic->argreg != 1 &&
2377 ((isOperandInFarSpace(IC_LEFT(ic)) && !isOperandInReg(IC_LEFT(ic))) ||
2378 isOperandEqual(op,IC_LEFT(ic)))) return NULL;
2380 /* if CALL then make sure it is VOID || return value not used
2381 or the return value is assigned to this one */
2382 if (ic->op == CALL) {
2383 if (OP_SYMBOL(IC_RESULT(ic))->liveTo ==
2384 OP_SYMBOL(IC_RESULT(ic))->liveFrom) continue ;
2385 etype = getSpec(type = operandType(IC_RESULT(ic)));
2386 if (getSize(type) == 0 || isOperandEqual(op,IC_RESULT(ic)))
2391 /* special case of add with a [remat] */
2392 if (ic->op == '+' &&
2393 OP_SYMBOL(IC_LEFT(ic))->remat &&
2394 (isOperandInFarSpace(IC_RIGHT(ic)) &&
2395 !isOperandInReg(IC_RIGHT(ic)))) return NULL ;
2399 if (POINTER_GET(ic) && !isOperandEqual(IC_LEFT(ic),op) &&
2400 getSize(operandType(IC_LEFT(ic))) > 1 ) return NULL ;
2403 if (POINTER_SET(ic) && !isOperandEqual(IC_RESULT(ic),op) &&
2404 getSize(operandType(IC_RESULT(ic))) > 1 ) return NULL;
2406 /* conditionals can destroy 'b' - make sure B wont
2407 be used in this one*/
2408 if ((IS_CONDITIONAL(ic) || ic->op == '*' || ic->op == '/' ||
2409 ic->op == LEFT_OP || ic->op == RIGHT_OP ) &&
2410 getSize(operandType(op)) > 3) return NULL;
2412 /* if this is a cast to a bigger type */
2414 if (!IS_PTR(OP_SYM_TYPE(IC_RESULT(ic))) &&
2415 getSize(OP_SYM_TYPE(IC_RESULT(ic))) >
2416 getSize(OP_SYM_TYPE(IC_RIGHT(ic)))) {
2422 if (IC_RESULT(ic) && IS_SYMOP(IC_RESULT(ic)) &&
2423 !isOperandEqual(IC_RESULT(ic),op) &&
2424 ( ( ( isOperandInFarSpace(IC_RESULT(ic)) || OP_SYMBOL(IC_RESULT(ic))->onStack) &&
2425 !isOperandInReg(IC_RESULT(ic))) ||
2426 OP_SYMBOL(IC_RESULT(ic))->ruonly)) return NULL;
2428 if (IC_RIGHT(ic) && IS_SYMOP(IC_RIGHT(ic)) &&
2429 !isOperandEqual(IC_RIGHT(ic),op) &&
2430 (OP_SYMBOL(IC_RIGHT(ic))->liveTo >= ic->seq ||
2431 IS_TRUE_SYMOP(IC_RIGHT(ic)) ||
2432 OP_SYMBOL(IC_RIGHT(ic))->ruonly) &&
2433 ( ( isOperandInFarSpace(IC_RIGHT(ic)) || OP_SYMBOL(IC_RIGHT(ic))->onStack) &&
2434 !isOperandInReg(IC_RIGHT(ic))) ) return NULL;
2436 if (IC_LEFT(ic) && IS_SYMOP(IC_LEFT(ic)) &&
2437 !isOperandEqual(IC_LEFT(ic),op) &&
2438 (OP_SYMBOL(IC_LEFT(ic))->liveTo >= ic->seq ||
2439 IS_TRUE_SYMOP(IC_LEFT(ic)) ||
2440 OP_SYMBOL(IC_LEFT(ic))->ruonly) &&
2441 ( ( isOperandInFarSpace(IC_LEFT(ic)) || OP_SYMBOL(IC_LEFT(ic))->onStack) &&
2442 !isOperandInReg(IC_LEFT(ic))) ) return NULL;
2444 if (IC_LEFT(ic) && IC_RIGHT(ic) &&
2445 IS_ITEMP(IC_LEFT(ic)) && IS_ITEMP(IC_RIGHT(ic)) &&
2446 (isOperandInFarSpace(IC_LEFT(ic)) && !isOperandInReg(IC_LEFT(ic))) &&
2447 (isOperandInFarSpace(IC_RIGHT(ic)) && !isOperandInReg(IC_RIGHT(ic))))
2450 OP_SYMBOL(op)->ruonly = 1;
2451 if (OP_SYMBOL(op)->usl.spillLoc) {
2452 if (OP_SYMBOL(op)->spillA)
2453 OP_SYMBOL(op)->usl.spillLoc->allocreq--;
2454 OP_SYMBOL(op)->usl.spillLoc = NULL;
2459 /*-----------------------------------------------------------------*/
2460 /* isBitwiseOptimizable - requirements of JEAN LOUIS VERN */
2461 /*-----------------------------------------------------------------*/
2463 isBitwiseOptimizable (iCode * ic)
2465 sym_link *ltype = getSpec (operandType (IC_LEFT (ic)));
2466 sym_link *rtype = getSpec (operandType (IC_RIGHT (ic)));
2468 /* bitwise operations are considered optimizable
2469 under the following conditions (Jean-Louis VERN)
2481 if ( IS_LITERAL (rtype) ||
2482 (IS_BITVAR (ltype) && IN_BITSPACE (SPEC_OCLS (ltype))))
2488 /*-----------------------------------------------------------------*/
2489 /* packRegsForAccUse - pack registers for acc use */
2490 /*-----------------------------------------------------------------*/
2492 packRegsForAccUse (iCode * ic)
2496 /* if this is an aggregate, e.g. a one byte char array */
2497 if (IS_AGGREGATE(operandType(IC_RESULT(ic)))) {
2501 /* if we are calling a reentrant function that has stack parameters */
2502 if (ic->op == CALL &&
2503 IFFUNC_ISREENT(operandType(IC_LEFT(ic))) &&
2504 FUNC_HASSTACKPARM(operandType(IC_LEFT(ic))))
2507 if (ic->op == PCALL &&
2508 IFFUNC_ISREENT(operandType(IC_LEFT(ic))->next) &&
2509 FUNC_HASSTACKPARM(operandType(IC_LEFT(ic))->next))
2512 /* if + or - then it has to be one byte result */
2513 if ((ic->op == '+' || ic->op == '-')
2514 && getSize (operandType (IC_RESULT (ic))) > 1)
2517 /* if shift operation make sure right side is not a literal */
2518 if (ic->op == RIGHT_OP &&
2519 (isOperandLiteral (IC_RIGHT (ic)) ||
2520 getSize (operandType (IC_RESULT (ic))) > 1))
2523 if (ic->op == LEFT_OP &&
2524 (isOperandLiteral (IC_RIGHT (ic)) ||
2525 getSize (operandType (IC_RESULT (ic))) > 1))
2528 if (IS_BITWISE_OP (ic) &&
2529 getSize (operandType (IC_RESULT (ic))) > 1)
2533 /* has only one definition */
2534 if (bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) > 1)
2537 /* has only one use */
2538 if (bitVectnBitsOn (OP_USES (IC_RESULT (ic))) > 1)
2541 /* and the usage immediately follows this iCode */
2542 if (!(uic = hTabItemWithKey (iCodehTab,
2543 bitVectFirstBit (OP_USES (IC_RESULT (ic))))))
2546 if (ic->next != uic)
2549 /* if it is a conditional branch then we definitely can */
2553 if (uic->op == JUMPTABLE)
2556 /* if the usage is not is an assignment
2557 or an arithmetic / bitwise / shift operation then not */
2558 if (POINTER_SET (uic) &&
2559 getSize (aggrToPtr (operandType (IC_RESULT (uic)), FALSE)) > 1)
2562 if (uic->op != '=' &&
2563 !IS_ARITHMETIC_OP (uic) &&
2564 !IS_BITWISE_OP (uic) &&
2565 uic->op != LEFT_OP &&
2566 uic->op != RIGHT_OP)
2569 /* if used in ^ operation then make sure right is not a
2571 if (uic->op == '^' && isOperandLiteral (IC_RIGHT (uic)))
2574 /* if shift operation make sure right side is not a literal */
2575 if (uic->op == RIGHT_OP &&
2576 (isOperandLiteral (IC_RIGHT (uic)) ||
2577 getSize (operandType (IC_RESULT (uic))) > 1))
2580 if (uic->op == LEFT_OP &&
2581 (isOperandLiteral (IC_RIGHT (uic)) ||
2582 getSize (operandType (IC_RESULT (uic))) > 1))
2585 /* make sure that the result of this icode is not on the
2586 stack, since acc is used to compute stack offset */
2587 if (isOperandOnStack(IC_RESULT(uic)))
2590 /* if either one of them in far space then we cannot */
2591 if ((IS_TRUE_SYMOP (IC_LEFT (uic)) &&
2592 isOperandInFarSpace (IC_LEFT (uic))) ||
2593 (IS_TRUE_SYMOP (IC_RIGHT (uic)) &&
2594 isOperandInFarSpace (IC_RIGHT (uic))))
2597 /* if the usage has only one operand then we can */
2598 if (IC_LEFT (uic) == NULL ||
2599 IC_RIGHT (uic) == NULL)
2602 /* make sure this is on the left side if not
2603 a '+' since '+' is commutative */
2604 if (ic->op != '+' &&
2605 IC_LEFT (uic)->key != IC_RESULT (ic)->key)
2608 /* if the other one is not on stack then we can */
2609 if (IC_LEFT (uic)->key == IC_RESULT (ic)->key &&
2610 (IS_ITEMP (IC_RIGHT (uic)) ||
2611 (IS_TRUE_SYMOP (IC_RIGHT (uic)) &&
2612 !OP_SYMBOL (IC_RIGHT (uic))->onStack)))
2615 if (IC_RIGHT (uic)->key == IC_RESULT (ic)->key &&
2616 (IS_ITEMP (IC_LEFT (uic)) ||
2617 (IS_TRUE_SYMOP (IC_LEFT (uic)) &&
2618 !OP_SYMBOL (IC_LEFT (uic))->onStack)))
2624 OP_SYMBOL (IC_RESULT (ic))->accuse = 1;
2629 /*-----------------------------------------------------------------*/
2630 /* packForPush - hueristics to reduce iCode for pushing */
2631 /*-----------------------------------------------------------------*/
2633 packForPush (iCode * ic, eBBlock * ebp)
2638 if ((ic->op != IPUSH && ic->op != SEND) || !IS_ITEMP (IC_LEFT (ic)))
2641 /* must have only definition & one usage */
2642 if (bitVectnBitsOn (OP_DEFS (IC_LEFT (ic))) != 1 ||
2643 bitVectnBitsOn (OP_USES (IC_LEFT (ic))) != 1)
2646 /* find the definition */
2647 if (!(dic = hTabItemWithKey (iCodehTab,
2648 bitVectFirstBit (OP_DEFS (IC_LEFT (ic))))))
2651 if (dic->op != '=' || POINTER_SET (dic))
2654 if (dic->eBBlockNum != ic->eBBlockNum) return ;
2656 /* make sure the right side does not have any definitions
2658 dbv = OP_DEFS(IC_RIGHT(dic));
2659 for (lic = ic; lic && lic != dic ; lic = lic->prev) {
2660 if (bitVectBitValue(dbv,lic->key)) return ;
2662 /* make sure they have the same type */
2663 if (IS_SPEC(operandType(IC_LEFT(ic))))
2665 sym_link *itype=operandType(IC_LEFT(ic));
2666 sym_link *ditype=operandType(IC_RIGHT(dic));
2668 if (SPEC_USIGN(itype)!=SPEC_USIGN(ditype) ||
2669 SPEC_LONG(itype)!=SPEC_LONG(ditype))
2672 /* extend the live range of replaced operand if needed */
2673 if (OP_SYMBOL(IC_RIGHT(dic))->liveTo < OP_SYMBOL(IC_LEFT(ic))->liveTo) {
2674 OP_SYMBOL(IC_RIGHT(dic))->liveTo = OP_SYMBOL(IC_LEFT(ic))->liveTo;
2675 OP_SYMBOL(IC_RIGHT(dic))->clashes =
2676 bitVectUnion(OP_SYMBOL(IC_RIGHT(dic))->clashes,
2677 OP_SYMBOL(IC_LEFT(ic))->clashes);
2679 for (lic = ic; lic && lic != dic; lic = lic->prev)
2681 bitVectUnSetBit (lic->rlive, IC_LEFT (ic)->key);
2682 if (IS_ITEMP (IC_RIGHT (dic)))
2683 bitVectSetBit (lic->rlive, IC_RIGHT (dic)->key);
2685 /* we now we know that it has one & only one def & use
2686 and the that the definition is an assignment */
2687 IC_LEFT (ic) = IC_RIGHT (dic);
2689 remiCodeFromeBBlock (ebp, dic);
2690 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2691 hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
2694 /*-----------------------------------------------------------------*/
2695 /* packRegisters - does some transformations to reduce register */
2697 /*-----------------------------------------------------------------*/
2699 packRegisters (eBBlock * ebp)
2709 /* look for assignments of the form */
2710 /* iTempNN = TRueSym (someoperation) SomeOperand */
2712 /* TrueSym := iTempNN:1 */
2713 for (ic = ebp->sch; ic; ic = ic->next)
2717 /* find assignment of the form TrueSym := iTempNN:1 */
2718 if (ic->op == '=' && !POINTER_SET (ic))
2719 change += packRegsForAssign (ic, ebp);
2726 for (ic = ebp->sch; ic; ic = ic->next)
2729 /* if this is an itemp & result of a address of a true sym
2730 then mark this as rematerialisable */
2731 if (ic->op == ADDRESS_OF &&
2732 IS_ITEMP (IC_RESULT (ic)) &&
2733 IS_TRUE_SYMOP (IC_LEFT (ic)) &&
2734 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1 &&
2735 !OP_SYMBOL (IC_LEFT (ic))->onStack)
2738 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2739 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2740 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2744 /* if this is an itemp & used as a pointer
2745 & assigned to a literal then remat */
2746 if (IS_ASSIGN_ICODE(ic) &&
2747 IS_ITEMP(IC_RESULT(ic)) &&
2748 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1 &&
2749 isOperandLiteral(IC_RIGHT(ic)))
2751 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2752 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2753 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2756 /* if straight assignment then carry remat flag if
2757 this is the only definition */
2758 if (ic->op == '=' &&
2759 !POINTER_SET (ic) &&
2760 IS_SYMOP (IC_RIGHT (ic)) &&
2761 OP_SYMBOL (IC_RIGHT (ic))->remat &&
2762 !IS_CAST_ICODE(OP_SYMBOL (IC_RIGHT (ic))->rematiCode) &&
2763 bitVectnBitsOn (OP_SYMBOL (IC_RESULT (ic))->defs) <= 1)
2766 OP_SYMBOL (IC_RESULT (ic))->remat =
2767 OP_SYMBOL (IC_RIGHT (ic))->remat;
2768 OP_SYMBOL (IC_RESULT (ic))->rematiCode =
2769 OP_SYMBOL (IC_RIGHT (ic))->rematiCode;
2772 /* if cast to a generic pointer & the pointer being
2773 cast is remat, then we can remat this cast as well */
2774 if (ic->op == CAST &&
2775 IS_SYMOP(IC_RIGHT(ic)) &&
2776 !OP_SYMBOL(IC_RESULT(ic))->isreqv &&
2777 OP_SYMBOL(IC_RIGHT(ic))->remat ) {
2778 sym_link *to_type = operandType(IC_LEFT(ic));
2779 sym_link *from_type = operandType(IC_RIGHT(ic));
2780 if (IS_GENPTR(to_type) && IS_PTR(from_type)) {
2781 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2782 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2783 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2787 /* if this is a +/- operation with a rematerizable
2788 then mark this as rematerializable as well */
2789 if ((ic->op == '+' || ic->op == '-') &&
2790 (IS_SYMOP (IC_LEFT (ic)) &&
2791 IS_ITEMP (IC_RESULT (ic)) &&
2792 OP_SYMBOL (IC_LEFT (ic))->remat &&
2793 (!IS_SYMOP (IC_RIGHT (ic)) || !IS_CAST_ICODE(OP_SYMBOL (IC_RIGHT (ic))->rematiCode)) &&
2794 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1 &&
2795 IS_OP_LITERAL (IC_RIGHT (ic))))
2798 //int i = operandLitValue(IC_RIGHT(ic));
2799 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2800 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2801 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2804 /* mark the pointer usages */
2805 if (POINTER_SET (ic) && IS_SYMOP (IC_RESULT (ic)))
2806 OP_SYMBOL (IC_RESULT (ic))->uptr = 1;
2808 if (POINTER_GET (ic) && IS_SYMOP (IC_LEFT (ic)))
2809 OP_SYMBOL (IC_LEFT (ic))->uptr = 1;
2811 if (ic->op == RETURN && IS_SYMOP (IC_LEFT(ic)))
2812 OP_SYMBOL (IC_LEFT (ic))->uptr = 1;
2814 if (ic->op == RECEIVE && ic->argreg == 1 &&
2815 IS_SYMOP (IC_RESULT (ic)) &&
2816 getSize (operandType(IC_RESULT(ic))) <= 3)
2817 OP_SYMBOL (IC_RESULT(ic))->uptr = 1;
2819 if (ic->op == SEND && ic->argreg == 1 &&
2820 IS_SYMOP(IC_LEFT(ic)) &&
2821 getSize (aggrToPtr(operandType(IC_LEFT(ic)),FALSE)) <= 3)
2822 OP_SYMBOL (IC_LEFT(ic))->uptr = 1;
2826 /* if we are using a symbol on the stack
2827 then we should say ds390_ptrRegReq */
2828 if (ic->op == IFX && IS_SYMOP (IC_COND (ic)))
2829 ds390_ptrRegReq += ((OP_SYMBOL (IC_COND (ic))->onStack ? !options.stack10bit : 0) +
2830 OP_SYMBOL (IC_COND (ic))->iaccess);
2831 else if (ic->op == JUMPTABLE && IS_SYMOP (IC_JTCOND (ic)))
2832 ds390_ptrRegReq += ((OP_SYMBOL (IC_JTCOND (ic))->onStack ? !options.stack10bit : 0) +
2833 OP_SYMBOL (IC_JTCOND (ic))->iaccess);
2836 if (IS_SYMOP (IC_LEFT (ic)))
2837 ds390_ptrRegReq += ((OP_SYMBOL (IC_LEFT (ic))->onStack ? !options.stack10bit : 0) +
2838 OP_SYMBOL (IC_LEFT (ic))->iaccess);
2839 if (IS_SYMOP (IC_RIGHT (ic)))
2840 ds390_ptrRegReq += ((OP_SYMBOL (IC_RIGHT (ic))->onStack ? !options.stack10bit : 0) +
2841 OP_SYMBOL (IC_RIGHT (ic))->iaccess);
2842 if (IS_SYMOP (IC_RESULT (ic)))
2843 ds390_ptrRegReq += ((OP_SYMBOL (IC_RESULT (ic))->onStack ? !options.stack10bit : 0) +
2844 OP_SYMBOL (IC_RESULT (ic))->iaccess);
2848 /* if the condition of an if instruction
2849 is defined in the previous instruction and
2850 this is the only usage then
2851 mark the itemp as a conditional */
2852 if ((IS_CONDITIONAL (ic) ||
2853 (IS_BITWISE_OP(ic) && isBitwiseOptimizable (ic))) &&
2854 ic->next && ic->next->op == IFX &&
2855 bitVectnBitsOn (OP_USES(IC_RESULT(ic)))==1 &&
2856 isOperandEqual (IC_RESULT (ic), IC_COND (ic->next)) &&
2857 OP_SYMBOL (IC_RESULT (ic))->liveTo <= ic->next->seq)
2859 OP_SYMBOL (IC_RESULT (ic))->regType = REG_CND;
2863 /* reduce for support function calls */
2864 if (ic->supportRtn || ic->op == '+' || ic->op == '-')
2865 packRegsForSupport (ic, ebp);
2867 /* some cases the redundant moves can
2868 can be eliminated for return statements . Can be elminated for the first SEND */
2869 if ((ic->op == RETURN ||
2870 ((ic->op == SEND || ic->op == RECEIVE)&& ic->argreg == 1)) &&
2871 !isOperandInFarSpace (IC_LEFT (ic)) &&
2874 packRegsDPTRuse (IC_LEFT (ic));
2877 if (ic->op == CALL) {
2878 sym_link *ftype = operandType(IC_LEFT(ic));
2879 if (getSize(operandType(IC_RESULT(ic))) <= 4 &&
2880 !IFFUNC_ISBUILTIN(ftype)) {
2881 packRegsDPTRuse (IC_RESULT (ic));
2885 /* if pointer set & left has a size more than
2886 one and right is not in far space */
2887 if (POINTER_SET (ic) &&
2888 !isOperandInFarSpace (IC_RIGHT (ic)) &&
2889 IS_SYMOP (IC_RESULT (ic)) &&
2890 !OP_SYMBOL (IC_RESULT (ic))->remat &&
2891 !IS_OP_RUONLY (IC_RIGHT (ic)) &&
2892 getSize (aggrToPtr (operandType (IC_RESULT (ic)), FALSE)) > 1) {
2894 packRegsDPTRuse (IC_RESULT (ic));
2897 /* if pointer get */
2898 if (POINTER_GET (ic) &&
2899 !isOperandInFarSpace (IC_RESULT (ic)) &&
2900 IS_SYMOP (IC_LEFT (ic)) &&
2901 !OP_SYMBOL (IC_LEFT (ic))->remat &&
2902 !IS_OP_RUONLY (IC_RESULT (ic)) &&
2903 getSize (aggrToPtr (operandType (IC_LEFT (ic)), FALSE)) > 1) {
2905 packRegsDPTRuse (IC_LEFT (ic));
2908 /* if this is cast for intergral promotion then
2909 check if only use of the definition of the
2910 operand being casted/ if yes then replace
2911 the result of that arithmetic operation with
2912 this result and get rid of the cast */
2915 sym_link *fromType = operandType (IC_RIGHT (ic));
2916 sym_link *toType = operandType (IC_LEFT (ic));
2918 if (IS_INTEGRAL (fromType) && IS_INTEGRAL (toType) &&
2919 getSize (fromType) != getSize (toType) &&
2920 SPEC_USIGN (fromType) == SPEC_USIGN (toType))
2923 iCode *dic = packRegsDPTRuse (IC_RIGHT (ic));
2926 if (IS_ARITHMETIC_OP (dic))
2928 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
2929 IC_RESULT (dic) = IC_RESULT (ic);
2930 remiCodeFromeBBlock (ebp, ic);
2931 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
2932 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
2933 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
2937 OP_SYMBOL (IC_RIGHT (ic))->ruonly = 0;
2943 /* if the type from and type to are the same
2944 then if this is the only use then packit */
2945 if (compareType (operandType (IC_RIGHT (ic)),
2946 operandType (IC_LEFT (ic))) == 1)
2948 iCode *dic = packRegsDPTRuse (IC_RIGHT (ic));
2951 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
2952 IC_RESULT (dic) = IC_RESULT (ic);
2953 remiCodeFromeBBlock (ebp, ic);
2954 bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
2955 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
2956 OP_DEFS(IC_RESULT (dic))=bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
2964 iTempNN := (some variable in farspace) V1
2969 if (ic->op == IPUSH || ic->op == SEND)
2971 packForPush (ic, ebp);
2975 /* pack registers for accumulator use, when the
2976 result of an arithmetic or bit wise operation
2977 has only one use, that use is immediately following
2978 the defintion and the using iCode has only one
2979 operand or has two operands but one is literal &
2980 the result of that operation is not on stack then
2981 we can leave the result of this operation in acc:b
2983 if ((IS_ARITHMETIC_OP (ic)
2984 || IS_CONDITIONAL(ic)
2985 || IS_BITWISE_OP (ic)
2986 || ic->op == LEFT_OP || ic->op == RIGHT_OP
2987 || (ic->op == ADDRESS_OF && isOperandOnStack (IC_LEFT (ic)))
2989 IS_ITEMP (IC_RESULT (ic)) &&
2990 getSize (operandType (IC_RESULT (ic))) <= 2)
2992 packRegsForAccUse (ic);
2997 /*-----------------------------------------------------------------*/
2998 /* assignRegisters - assigns registers to each live range as need */
2999 /*-----------------------------------------------------------------*/
3001 ds390_assignRegisters (eBBlock ** ebbs, int count)
3006 setToNull ((void *) &_G.funcrUsed);
3007 setToNull ((void *) &_G.regAssigned);
3008 setToNull ((void *) &_G.totRegAssigned);
3009 setToNull ((void *) &_G.funcrUsed);
3010 ds390_ptrRegReq = _G.stackExtend = _G.dataExtend = 0;
3012 if (options.model != MODEL_FLAT24) options.stack10bit = 0;
3013 /* change assignments this will remove some
3014 live ranges reducing some register pressure */
3015 for (i = 0; i < count; i++)
3016 packRegisters (ebbs[i]);
3018 if (options.dump_pack)
3019 dumpEbbsToFileExt (DUMP_PACK, ebbs, count);
3021 /* first determine for each live range the number of
3022 registers & the type of registers required for each */
3025 /* and serially allocate registers */
3026 serialRegAssign (ebbs, count);
3033 /* if stack was extended then tell the user */
3036 /* werror(W_TOOMANY_SPILS,"stack", */
3037 /* _G.stackExtend,currFunc->name,""); */
3043 /* werror(W_TOOMANY_SPILS,"data space", */
3044 /* _G.dataExtend,currFunc->name,""); */
3048 /* after that create the register mask
3049 for each of the instruction */
3050 createRegMask (ebbs, count);
3052 /* redo that offsets for stacked automatic variables */
3054 redoStackOffsets ();
3056 if (options.dump_rassgn) {
3057 dumpEbbsToFileExt (DUMP_RASSGN, ebbs, count);
3058 dumpLiveRanges (DUMP_LRANGE, liveRanges);
3061 /* do the overlaysegment stuff SDCCmem.c */
3062 doOverlays (ebbs, count);
3064 /* now get back the chain */
3065 ic = iCodeLabelOptimize (iCodeFromeBBlock (ebbs, count));
3070 /* free up any _G.stackSpil locations allocated */
3071 applyToSet (_G.stackSpil, deallocStackSpil);
3073 setToNull ((void **) &_G.stackSpil);
3074 setToNull ((void **) &_G.spiltSet);
3075 /* mark all registers as free */