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 /*-----------------------------------------------------------------*/
45 bitVect *totRegAssigned; /* final set of LRs that got into registers */
48 bitVect *funcrUsed; /* registers used in a function */
54 /* Shared with gen.c */
55 int ds390_ptrRegReq; /* one byte pointer register required */
61 {REG_GPR, R2_IDX, REG_GPR, "r2", "ar2", "0", 2, 1, 1},
62 {REG_GPR, R3_IDX, REG_GPR, "r3", "ar3", "0", 3, 1, 1},
63 {REG_GPR, R4_IDX, REG_GPR, "r4", "ar4", "0", 4, 1, 1},
64 {REG_GPR, R5_IDX, REG_GPR, "r5", "ar5", "0", 5, 1, 1},
65 {REG_GPR, R6_IDX, REG_GPR, "r6", "ar6", "0", 6, 1, 1},
66 {REG_GPR, R7_IDX, REG_GPR, "r7", "ar7", "0", 7, 1, 1},
67 {REG_PTR, R0_IDX, REG_PTR, "r0", "ar0", "0", 0, 1, 1},
68 {REG_PTR, R1_IDX, REG_PTR, "r1", "ar1", "0", 1, 1, 1},
69 {REG_GPR, X8_IDX, REG_GPR, "x8", "x8", "xreg", 0, 0, 0},
70 {REG_GPR, X9_IDX, REG_GPR, "x9", "x9", "xreg", 1, 0, 0},
71 {REG_GPR, X10_IDX, REG_GPR, "x10", "x10", "xreg", 2, 0, 0},
72 {REG_GPR, X11_IDX, REG_GPR, "x11", "x11", "xreg", 3, 0, 0},
73 {REG_GPR, X12_IDX, REG_GPR, "x12", "x12", "xreg", 4, 0, 0},
74 {REG_CND, CND_IDX, REG_GPR, "C", "C", "xreg", 0, 0, 0},
75 {REG_GPR, DPL_IDX, REG_GPR, "dpl", "dpl", "dpl", 0, 0, 0},
76 {REG_GPR, DPH_IDX, REG_GPR, "dph", "dph", "dph", 0, 0, 0},
77 {REG_GPR, DPX_IDX, REG_GPR, "dpx", "dpx", "dpx", 0, 0, 0},
78 {REG_GPR, B_IDX, REG_GPR, "b", "b", "b", 0, 0, 0},
81 static void spillThis (symbol *);
82 static void freeAllRegs ();
84 /*-----------------------------------------------------------------*/
85 /* allocReg - allocates register of given type */
86 /*-----------------------------------------------------------------*/
92 for (i = 0; i < ds390_nRegs; i++)
95 /* if type is given as 0 then any
96 free register will do */
100 regs390[i].isFree = 0;
103 bitVectSetBit (currFunc->regsUsed, i);
106 /* other wise look for specific type
108 if (regs390[i].isFree &&
109 regs390[i].type == type)
111 regs390[i].isFree = 0;
114 bitVectSetBit (currFunc->regsUsed, i);
121 /*-----------------------------------------------------------------*/
122 /* ds390_regWithIdx - returns pointer to register wit index number */
123 /*-----------------------------------------------------------------*/
125 ds390_regWithIdx (int idx)
129 for (i = 0; i < ds390_nRegs; i++)
130 if (regs390[i].rIdx == idx)
133 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
134 "regWithIdx not found");
138 /*-----------------------------------------------------------------*/
139 /* freeReg - frees a register */
140 /*-----------------------------------------------------------------*/
147 /*-----------------------------------------------------------------*/
148 /* useReg - marks a register as used */
149 /*-----------------------------------------------------------------*/
157 /*-----------------------------------------------------------------*/
158 /* nFreeRegs - returns number of free registers */
159 /*-----------------------------------------------------------------*/
166 for (i = 0; i < ds390_nRegs; i++)
167 if (regs390[i].isFree && regs390[i].type == type)
172 /*-----------------------------------------------------------------*/
173 /* nfreeRegsType - free registers with type */
174 /*-----------------------------------------------------------------*/
176 nfreeRegsType (int type)
181 if ((nfr = nFreeRegs (type)) == 0)
182 return nFreeRegs (REG_GPR);
185 return nFreeRegs (type);
189 /*-----------------------------------------------------------------*/
190 /* allDefsOutOfRange - all definitions are out of a range */
191 /*-----------------------------------------------------------------*/
193 allDefsOutOfRange (bitVect * defs, int fseq, int toseq)
200 for (i = 0; i < defs->size; i++)
204 if (bitVectBitValue (defs, i) &&
205 (ic = hTabItemWithKey (iCodehTab, i)) &&
206 (ic->seq >= fseq && ic->seq <= toseq))
215 /*-----------------------------------------------------------------*/
216 /* computeSpillable - given a point find the spillable live ranges */
217 /*-----------------------------------------------------------------*/
219 computeSpillable (iCode * ic)
223 /* spillable live ranges are those that are live at this
224 point . the following categories need to be subtracted
226 a) - those that are already spilt
227 b) - if being used by this one
228 c) - defined by this one */
230 spillable = bitVectCopy (ic->rlive);
232 bitVectCplAnd (spillable, _G.spiltSet); /* those already spilt */
234 bitVectCplAnd (spillable, ic->uses); /* used in this one */
235 bitVectUnSetBit (spillable, ic->defKey);
236 spillable = bitVectIntersect (spillable, _G.regAssigned);
241 /*-----------------------------------------------------------------*/
242 /* noSpilLoc - return true if a variable has no spil location */
243 /*-----------------------------------------------------------------*/
245 noSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
247 return (sym->usl.spillLoc ? 0 : 1);
250 /*-----------------------------------------------------------------*/
251 /* hasSpilLoc - will return 1 if the symbol has spil location */
252 /*-----------------------------------------------------------------*/
254 hasSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
256 return (sym->usl.spillLoc ? 1 : 0);
259 /*-----------------------------------------------------------------*/
260 /* directSpilLoc - will return 1 if the splilocation is in direct */
261 /*-----------------------------------------------------------------*/
263 directSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
265 if (sym->usl.spillLoc &&
266 (IN_DIRSPACE (SPEC_OCLS (sym->usl.spillLoc->etype))))
272 /*-----------------------------------------------------------------*/
273 /* hasSpilLocnoUptr - will return 1 if the symbol has spil location */
274 /* but is not used as a pointer */
275 /*-----------------------------------------------------------------*/
277 hasSpilLocnoUptr (symbol * sym, eBBlock * ebp, iCode * ic)
279 return ((sym->usl.spillLoc && !sym->uptr) ? 1 : 0);
282 /*-----------------------------------------------------------------*/
283 /* rematable - will return 1 if the remat flag is set */
284 /*-----------------------------------------------------------------*/
286 rematable (symbol * sym, eBBlock * ebp, iCode * ic)
291 /*-----------------------------------------------------------------*/
292 /* notUsedInBlock - not used in this block */
293 /*-----------------------------------------------------------------*/
295 notUsedInBlock (symbol * sym, eBBlock * ebp, iCode * ic)
297 return (!bitVectBitsInCommon (sym->defs, ebp->usesDefs) &&
298 allDefsOutOfRange (sym->defs, ebp->fSeq, ebp->lSeq));
299 /* return (!bitVectBitsInCommon(sym->defs,ebp->usesDefs)); */
302 /*-----------------------------------------------------------------*/
303 /* notUsedInRemaining - not used or defined in remain of the block */
304 /*-----------------------------------------------------------------*/
306 notUsedInRemaining (symbol * sym, eBBlock * ebp, iCode * ic)
308 return ((usedInRemaining (operandFromSymbol (sym), ic) ? 0 : 1) &&
309 allDefsOutOfRange (sym->defs, ebp->fSeq, ebp->lSeq));
312 /*-----------------------------------------------------------------*/
313 /* allLRs - return true for all */
314 /*-----------------------------------------------------------------*/
316 allLRs (symbol * sym, eBBlock * ebp, iCode * ic)
321 /*-----------------------------------------------------------------*/
322 /* liveRangesWith - applies function to a given set of live range */
323 /*-----------------------------------------------------------------*/
325 liveRangesWith (bitVect * lrs, int (func) (symbol *, eBBlock *, iCode *),
326 eBBlock * ebp, iCode * ic)
331 if (!lrs || !lrs->size)
334 for (i = 1; i < lrs->size; i++)
337 if (!bitVectBitValue (lrs, i))
340 /* if we don't find it in the live range
341 hash table we are in serious trouble */
342 if (!(sym = hTabItemWithKey (liveRanges, i)))
344 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
345 "liveRangesWith could not find liveRange");
349 if (func (sym, ebp, ic) && bitVectBitValue (_G.regAssigned, sym->key))
350 addSetHead (&rset, sym);
357 /*-----------------------------------------------------------------*/
358 /* leastUsedLR - given a set determines which is the least used */
359 /*-----------------------------------------------------------------*/
361 leastUsedLR (set * sset)
363 symbol *sym = NULL, *lsym = NULL;
365 sym = lsym = setFirstItem (sset);
370 for (; lsym; lsym = setNextItem (sset))
373 /* if usage is the same then prefer
374 the spill the smaller of the two */
375 if (lsym->used == sym->used)
376 if (getSize (lsym->type) < getSize (sym->type))
380 if (lsym->used < sym->used)
385 setToNull ((void **) &sset);
390 /*-----------------------------------------------------------------*/
391 /* noOverLap - will iterate through the list looking for over lap */
392 /*-----------------------------------------------------------------*/
394 noOverLap (set * itmpStack, symbol * fsym)
398 for (sym = setFirstItem (itmpStack); sym;
399 sym = setNextItem (itmpStack))
401 if (bitVectBitValue(sym->clashes,fsym->key)) return 0;
406 /*-----------------------------------------------------------------*/
407 /* isFree - will return 1 if the a free spil location is found */
408 /*-----------------------------------------------------------------*/
413 V_ARG (symbol **, sloc);
414 V_ARG (symbol *, fsym);
416 /* if already found */
420 /* if it is free && and the itmp assigned to
421 this does not have any overlapping live ranges
422 with the one currently being assigned and
423 the size can be accomodated */
425 noOverLap (sym->usl.itmpStack, fsym) &&
426 getSize (sym->type) >= getSize (fsym->type))
435 /*-----------------------------------------------------------------*/
436 /* spillLRWithPtrReg :- will spil those live ranges which use PTR */
437 /*-----------------------------------------------------------------*/
439 spillLRWithPtrReg (symbol * forSym)
445 if (!_G.regAssigned ||
446 bitVectIsZero (_G.regAssigned))
449 r0 = ds390_regWithIdx (R0_IDX);
450 r1 = ds390_regWithIdx (R1_IDX);
452 /* for all live ranges */
453 for (lrsym = hTabFirstItem (liveRanges, &k); lrsym;
454 lrsym = hTabNextItem (liveRanges, &k))
458 /* if no registers assigned to it or
460 /* if it does not overlap with this then
461 not need to spill it */
463 if (lrsym->isspilt || !lrsym->nRegs ||
464 (lrsym->liveTo < forSym->liveFrom))
467 /* go thru the registers : if it is either
468 r0 or r1 then spil it */
469 for (j = 0; j < lrsym->nRegs; j++)
470 if (lrsym->regs[j] == r0 ||
471 lrsym->regs[j] == r1)
480 /*-----------------------------------------------------------------*/
481 /* createStackSpil - create a location on the stack to spil */
482 /*-----------------------------------------------------------------*/
484 createStackSpil (symbol * sym)
487 int useXstack, model, noOverlay;
491 /* first go try and find a free one that is already
492 existing on the stack */
493 if (applyToSet (_G.stackSpil, isFree, &sloc, sym))
495 /* found a free one : just update & return */
496 sym->usl.spillLoc = sloc;
499 addSetHead (&sloc->usl.itmpStack, sym);
503 /* could not then have to create one , this is the hard part
504 we need to allocate this on the stack : this is really a
505 hack!! but cannot think of anything better at this time */
507 if (sprintf (slocBuffer, "sloc%d", _G.slocNum++) >= sizeof (slocBuffer))
509 fprintf (stderr, "***Internal error: slocBuffer overflowed: %s:%d\n",
514 sloc = newiTemp (slocBuffer);
516 /* set the type to the spilling symbol */
517 sloc->type = copyLinkChain (sym->type);
518 sloc->etype = getSpec (sloc->type);
519 if (options.model == MODEL_SMALL) {
520 SPEC_SCLS (sloc->etype) = S_DATA;
522 SPEC_SCLS (sloc->etype) = S_XDATA;
524 SPEC_EXTR (sloc->etype) = 0;
525 SPEC_STAT (sloc->etype) = 0;
527 /* we don't allow it to be allocated`
528 onto the external stack since : so we
529 temporarily turn it off ; we also
530 turn off memory model to prevent
531 the spil from going to the external storage
532 and turn off overlaying
535 useXstack = options.useXstack;
536 model = options.model;
537 noOverlay = options.noOverlay;
538 options.noOverlay = 1;
540 /* options.model = options.useXstack = 0; */
544 options.useXstack = useXstack;
545 options.model = model;
546 options.noOverlay = noOverlay;
547 sloc->isref = 1; /* to prevent compiler warning */
549 /* if it is on the stack then update the stack */
550 if (IN_STACK (sloc->etype))
552 currFunc->stack += getSize (sloc->type);
553 _G.stackExtend += getSize (sloc->type);
556 _G.dataExtend += getSize (sloc->type);
558 /* add it to the _G.stackSpil set */
559 addSetHead (&_G.stackSpil, sloc);
560 sym->usl.spillLoc = sloc;
563 /* add it to the set of itempStack set
564 of the spill location */
565 addSetHead (&sloc->usl.itmpStack, sym);
569 /*-----------------------------------------------------------------*/
570 /* isSpiltOnStack - returns true if the spil location is on stack */
571 /*-----------------------------------------------------------------*/
573 isSpiltOnStack (symbol * sym)
583 /* if (sym->_G.stackSpil) */
586 if (!sym->usl.spillLoc)
589 etype = getSpec (sym->usl.spillLoc->type);
590 if (IN_STACK (etype))
596 /*-----------------------------------------------------------------*/
597 /* spillThis - spils a specific operand */
598 /*-----------------------------------------------------------------*/
600 spillThis (symbol * sym)
603 /* if this is rematerializable or has a spillLocation
604 we are okay, else we need to create a spillLocation
606 if (!(sym->remat || sym->usl.spillLoc))
607 createStackSpil (sym);
610 /* mark it has spilt & put it in the spilt set */
611 sym->isspilt = sym->spillA = 1;
612 _G.spiltSet = bitVectSetBit (_G.spiltSet, sym->key);
614 bitVectUnSetBit (_G.regAssigned, sym->key);
615 bitVectUnSetBit (_G.totRegAssigned, sym->key);
617 for (i = 0; i < sym->nRegs; i++)
621 freeReg (sym->regs[i]);
625 /* if spilt on stack then free up r0 & r1
626 if they could have been assigned to some
628 if (!ds390_ptrRegReq && isSpiltOnStack (sym))
630 ds390_ptrRegReq += !options.stack10bit;
631 spillLRWithPtrReg (sym);
634 if (sym->usl.spillLoc && !sym->remat)
635 sym->usl.spillLoc->allocreq++;
639 /*-----------------------------------------------------------------*/
640 /* selectSpil - select a iTemp to spil : rather a simple procedure */
641 /*-----------------------------------------------------------------*/
643 selectSpil (iCode * ic, eBBlock * ebp, symbol * forSym)
645 bitVect *lrcs = NULL;
649 /* get the spillable live ranges */
650 lrcs = computeSpillable (ic);
652 /* get all live ranges that are rematerizable */
653 if ((selectS = liveRangesWith (lrcs, rematable, ebp, ic)))
656 /* return the least used of these */
657 return leastUsedLR (selectS);
660 /* get live ranges with spillLocations in direct space */
661 if ((selectS = liveRangesWith (lrcs, directSpilLoc, ebp, ic)))
663 sym = leastUsedLR (selectS);
664 strcpy (sym->rname, (sym->usl.spillLoc->rname[0] ?
665 sym->usl.spillLoc->rname :
666 sym->usl.spillLoc->name));
668 /* mark it as allocation required */
669 sym->usl.spillLoc->allocreq++;
673 /* if the symbol is local to the block then */
674 if (forSym->liveTo < ebp->lSeq)
677 /* check if there are any live ranges allocated
678 to registers that are not used in this block */
679 if (!_G.blockSpil && (selectS = liveRangesWith (lrcs, notUsedInBlock, ebp, ic)))
681 sym = leastUsedLR (selectS);
682 /* if this is not rematerializable */
691 /* check if there are any live ranges that not
692 used in the remainder of the block */
693 if (!_G.blockSpil && (selectS = liveRangesWith (lrcs, notUsedInRemaining, ebp, ic)))
695 sym = leastUsedLR (selectS);
708 /* find live ranges with spillocation && not used as pointers */
709 if ((selectS = liveRangesWith (lrcs, hasSpilLocnoUptr, ebp, ic)))
712 sym = leastUsedLR (selectS);
713 /* mark this as allocation required */
714 sym->usl.spillLoc->allocreq++;
718 /* find live ranges with spillocation */
719 if ((selectS = liveRangesWith (lrcs, hasSpilLoc, ebp, ic)))
722 sym = leastUsedLR (selectS);
723 sym->usl.spillLoc->allocreq++;
727 /* couldn't find then we need to create a spil
728 location on the stack , for which one? the least
730 if ((selectS = liveRangesWith (lrcs, noSpilLoc, ebp, ic)))
733 /* return a created spil location */
734 sym = createStackSpil (leastUsedLR (selectS));
735 sym->usl.spillLoc->allocreq++;
739 /* this is an extreme situation we will spill
740 this one : happens very rarely but it does happen */
746 /*-----------------------------------------------------------------*/
747 /* spilSomething - spil some variable & mark registers as free */
748 /*-----------------------------------------------------------------*/
750 spilSomething (iCode * ic, eBBlock * ebp, symbol * forSym)
755 /* get something we can spil */
756 ssym = selectSpil (ic, ebp, forSym);
758 /* mark it as spilt */
759 ssym->isspilt = ssym->spillA = 1;
760 _G.spiltSet = bitVectSetBit (_G.spiltSet, ssym->key);
762 /* mark it as not register assigned &
763 take it away from the set */
764 bitVectUnSetBit (_G.regAssigned, ssym->key);
765 bitVectUnSetBit (_G.totRegAssigned, ssym->key);
767 /* mark the registers as free */
768 for (i = 0; i < ssym->nRegs; i++)
770 freeReg (ssym->regs[i]);
772 /* if spilt on stack then free up r0 & r1
773 if they could have been assigned to as gprs */
774 if (!ds390_ptrRegReq && isSpiltOnStack (ssym) && !options.stack10bit)
777 spillLRWithPtrReg (ssym);
780 /* if this was a block level spil then insert push & pop
781 at the start & end of block respectively */
784 iCode *nic = newiCode (IPUSH, operandFromSymbol (ssym), NULL);
785 /* add push to the start of the block */
786 addiCodeToeBBlock (ebp, nic, (ebp->sch->op == LABEL ?
787 ebp->sch->next : ebp->sch));
788 nic = newiCode (IPOP, operandFromSymbol (ssym), NULL);
789 /* add pop to the end of the block */
790 addiCodeToeBBlock (ebp, nic, NULL);
793 /* if spilt because not used in the remainder of the
794 block then add a push before this instruction and
795 a pop at the end of the block */
796 if (ssym->remainSpil)
799 iCode *nic = newiCode (IPUSH, operandFromSymbol (ssym), NULL);
800 /* add push just before this instruction */
801 addiCodeToeBBlock (ebp, nic, ic);
803 nic = newiCode (IPOP, operandFromSymbol (ssym), NULL);
804 /* add pop to the end of the block */
805 addiCodeToeBBlock (ebp, nic, NULL);
814 /*-----------------------------------------------------------------*/
815 /* getRegPtr - will try for PTR if not a GPR type if not spil */
816 /*-----------------------------------------------------------------*/
818 getRegPtr (iCode * ic, eBBlock * ebp, symbol * sym)
823 /* try for a ptr type */
824 if ((reg = allocReg (REG_PTR)))
827 /* try for gpr type */
828 if ((reg = allocReg (REG_GPR)))
831 /* we have to spil */
832 if (!spilSomething (ic, ebp, sym))
835 /* this looks like an infinite loop but
836 in really selectSpil will abort */
840 /*-----------------------------------------------------------------*/
841 /* getRegGpr - will try for GPR if not spil */
842 /*-----------------------------------------------------------------*/
844 getRegGpr (iCode * ic, eBBlock * ebp, symbol * sym)
849 /* try for gpr type */
850 if ((reg = allocReg (REG_GPR)))
853 if (!ds390_ptrRegReq)
854 if ((reg = allocReg (REG_PTR)))
857 /* we have to spil */
858 if (!spilSomething (ic, ebp, sym))
861 /* this looks like an infinite loop but
862 in really selectSpil will abort */
866 /*-----------------------------------------------------------------*/
867 /* getRegPtrNoSpil - get it cannot split */
868 /*-----------------------------------------------------------------*/
869 static regs *getRegPtrNoSpil()
873 /* try for a ptr type */
874 if ((reg = allocReg (REG_PTR)))
877 /* try for gpr type */
878 if ((reg = allocReg (REG_GPR)))
884 /*-----------------------------------------------------------------*/
885 /* getRegGprNoSpil - get it cannot split */
886 /*-----------------------------------------------------------------*/
887 static regs *getRegGprNoSpil()
891 if ((reg = allocReg (REG_GPR)))
894 if (!ds390_ptrRegReq)
895 if ((reg = allocReg (REG_PTR)))
901 /*-----------------------------------------------------------------*/
902 /* symHasReg - symbol has a given register */
903 /*-----------------------------------------------------------------*/
905 symHasReg (symbol * sym, regs * reg)
909 for (i = 0; i < sym->nRegs; i++)
910 if (sym->regs[i] == reg)
916 /*-----------------------------------------------------------------*/
917 /* deassignLRs - check the live to and if they have registers & are */
918 /* not spilt then free up the registers */
919 /*-----------------------------------------------------------------*/
921 deassignLRs (iCode * ic, eBBlock * ebp)
927 for (sym = hTabFirstItem (liveRanges, &k); sym;
928 sym = hTabNextItem (liveRanges, &k))
932 /* if it does not end here */
933 if (sym->liveTo > ic->seq)
936 /* if it was spilt on stack then we can
937 mark the stack spil location as free */
942 sym->usl.spillLoc->isFree = 1;
948 if (!bitVectBitValue (_G.regAssigned, sym->key))
951 /* special case check if this is an IFX &
952 the privious one was a pop and the
953 previous one was not spilt then keep track
955 if (ic->op == IFX && ic->prev &&
956 ic->prev->op == IPOP &&
957 !ic->prev->parmPush &&
958 !OP_SYMBOL (IC_LEFT (ic->prev))->isspilt)
959 psym = OP_SYMBOL (IC_LEFT (ic->prev));
965 bitVectUnSetBit (_G.regAssigned, sym->key);
967 /* if the result of this one needs registers
968 and does not have it then assign it right
970 if (IC_RESULT (ic) &&
971 !(SKIP_IC2 (ic) || /* not a special icode */
972 ic->op == JUMPTABLE ||
978 (result = OP_SYMBOL (IC_RESULT (ic))) && /* has a result */
979 result->liveTo > ic->seq && /* and will live beyond this */
980 result->liveTo <= ebp->lSeq && /* does not go beyond this block */
981 result->regType == sym->regType && /* same register types */
982 result->nRegs && /* which needs registers */
983 !result->isspilt && /* and does not already have them */
985 !bitVectBitValue (_G.regAssigned, result->key) &&
986 /* the number of free regs + number of regs in this LR
987 can accomodate the what result Needs */
988 ((nfreeRegsType (result->regType) +
989 sym->nRegs) >= result->nRegs)
993 for (i = 0; i < result->nRegs; i++)
995 result->regs[i] = sym->regs[i];
997 result->regs[i] = getRegGpr (ic, ebp, result);
999 _G.regAssigned = bitVectSetBit (_G.regAssigned, result->key);
1000 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, result->key);
1004 /* free the remaining */
1005 for (; i < sym->nRegs; i++)
1009 if (!symHasReg (psym, sym->regs[i]))
1010 freeReg (sym->regs[i]);
1013 freeReg (sym->regs[i]);
1020 /*-----------------------------------------------------------------*/
1021 /* reassignLR - reassign this to registers */
1022 /*-----------------------------------------------------------------*/
1024 reassignLR (operand * op)
1026 symbol *sym = OP_SYMBOL (op);
1029 /* not spilt any more */
1030 sym->isspilt = sym->spillA = sym->blockSpil = sym->remainSpil = 0;
1031 bitVectUnSetBit (_G.spiltSet, sym->key);
1033 _G.regAssigned = bitVectSetBit (_G.regAssigned, sym->key);
1034 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, sym->key);
1038 for (i = 0; i < sym->nRegs; i++)
1039 sym->regs[i]->isFree = 0;
1042 /*-----------------------------------------------------------------*/
1043 /* willCauseSpill - determines if allocating will cause a spill */
1044 /*-----------------------------------------------------------------*/
1046 willCauseSpill (int nr, int rt)
1048 /* first check if there are any avlb registers
1049 of te type required */
1052 /* special case for pointer type
1053 if pointer type not avlb then
1054 check for type gpr */
1055 if (nFreeRegs (rt) >= nr)
1057 if (nFreeRegs (REG_GPR) >= nr)
1062 if (ds390_ptrRegReq)
1064 if (nFreeRegs (rt) >= nr)
1069 if (nFreeRegs (REG_PTR) +
1070 nFreeRegs (REG_GPR) >= nr)
1075 /* it will cause a spil */
1079 /*-----------------------------------------------------------------*/
1080 /* positionRegs - the allocator can allocate same registers to res- */
1081 /* ult and operand, if this happens make sure they are in the same */
1082 /* position as the operand otherwise chaos results */
1083 /*-----------------------------------------------------------------*/
1085 positionRegs (symbol * result, symbol * opsym)
1087 int count = min (result->nRegs, opsym->nRegs);
1088 int i, j = 0, shared = 0;
1091 /* if the result has been spilt then cannot share */
1096 /* first make sure that they actually share */
1097 for (i = 0; i < count; i++)
1099 for (j = 0; j < count; j++)
1101 if (result->regs[i] == opsym->regs[j] && i != j)
1111 regs *tmp = result->regs[i];
1112 result->regs[i] = result->regs[j];
1113 result->regs[j] = tmp;
1120 /*-----------------------------------------------------------------*/
1121 /* serialRegAssign - serially allocate registers to the variables */
1122 /*-----------------------------------------------------------------*/
1124 serialRegAssign (eBBlock ** ebbs, int count)
1128 /* for all blocks */
1129 for (i = 0; i < count; i++)
1134 if (ebbs[i]->noPath &&
1135 (ebbs[i]->entryLabel != entryLabel &&
1136 ebbs[i]->entryLabel != returnLabel))
1139 /* of all instructions do */
1140 for (ic = ebbs[i]->sch; ic; ic = ic->next)
1143 /* if this is an ipop that means some live
1144 range will have to be assigned again */
1146 reassignLR (IC_LEFT (ic));
1148 /* if result is present && is a true symbol */
1149 if (IC_RESULT (ic) && ic->op != IFX &&
1150 IS_TRUE_SYMOP (IC_RESULT (ic)))
1151 OP_SYMBOL (IC_RESULT (ic))->allocreq++;
1153 /* take away registers from live
1154 ranges that end at this instruction */
1155 deassignLRs (ic, ebbs[i]);
1157 /* some don't need registers */
1158 if (SKIP_IC2 (ic) ||
1159 ic->op == JUMPTABLE ||
1163 (IC_RESULT (ic) && POINTER_SET (ic)))
1166 /* now we need to allocate registers
1167 only for the result */
1170 symbol *sym = OP_SYMBOL (IC_RESULT (ic));
1176 /* if it does not need or is spilt
1177 or is already assigned to registers
1178 or will not live beyond this instructions */
1181 bitVectBitValue (_G.regAssigned, sym->key) ||
1182 sym->liveTo <= ic->seq)
1185 /* if some liverange has been spilt at the block level
1186 and this one live beyond this block then spil this
1188 if (_G.blockSpil && sym->liveTo > ebbs[i]->lSeq)
1193 /* if trying to allocate this will cause
1194 a spill and there is nothing to spill
1195 or this one is rematerializable then
1197 willCS = willCauseSpill (sym->nRegs, sym->regType);
1198 spillable = computeSpillable (ic);
1200 (willCS && bitVectIsZero (spillable)))
1208 /* if it has a spillocation & is used less than
1209 all other live ranges then spill this */
1211 if (sym->usl.spillLoc) {
1212 symbol *leastUsed = leastUsedLR (liveRangesWith (spillable,
1213 allLRs, ebbs[i], ic));
1214 if (leastUsed && leastUsed->used > sym->used) {
1219 /* if none of the liveRanges have a spillLocation then better
1220 to spill this one than anything else already assigned to registers */
1221 if (liveRangesWith(spillable,noSpilLoc,ebbs[i],ic)) {
1228 /* if we need ptr regs for the right side
1230 if (POINTER_GET (ic) && IS_SYMOP (IC_LEFT (ic))
1231 && getSize (OP_SYMBOL (IC_LEFT (ic))->type)
1232 <= (unsigned) PTRSIZE)
1237 /* else we assign registers to it */
1238 _G.regAssigned = bitVectSetBit (_G.regAssigned, sym->key);
1239 _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, sym->key);
1241 for (j = 0; j < sym->nRegs; j++)
1243 if (sym->regType == REG_PTR)
1244 sym->regs[j] = getRegPtr (ic, ebbs[i], sym);
1246 sym->regs[j] = getRegGpr (ic, ebbs[i], sym);
1248 /* if the allocation falied which means
1249 this was spilt then break */
1253 /* if it shares registers with operands make sure
1254 that they are in the same position */
1255 if (IC_LEFT (ic) && IS_SYMOP (IC_LEFT (ic)) &&
1256 OP_SYMBOL (IC_LEFT (ic))->nRegs && ic->op != '=')
1257 positionRegs (OP_SYMBOL (IC_RESULT (ic)),
1258 OP_SYMBOL (IC_LEFT (ic)));
1259 /* do the same for the right operand */
1260 if (IC_RIGHT (ic) && IS_SYMOP (IC_RIGHT (ic)) &&
1261 OP_SYMBOL (IC_RIGHT (ic))->nRegs)
1262 positionRegs (OP_SYMBOL (IC_RESULT (ic)),
1263 OP_SYMBOL (IC_RIGHT (ic)));
1276 /*-----------------------------------------------------------------*/
1277 /* fillGaps - Try to fill in the Gaps left by Pass1 */
1278 /*-----------------------------------------------------------------*/
1279 static void fillGaps()
1284 if (getenv("DISABLE_FILL_GAPS")) return;
1285 /* look for livernages that was spilt by the allocator */
1286 for (sym = hTabFirstItem(liveRanges,&key) ; sym ;
1287 sym = hTabNextItem(liveRanges,&key)) {
1292 if (!sym->spillA || !sym->clashes || sym->remat) continue ;
1294 /* find the liveRanges this one clashes with, that are
1295 still assigned to registers & mark the registers as used*/
1296 for ( i = 0 ; i < sym->clashes->size ; i ++) {
1300 if (bitVectBitValue(sym->clashes,i) == 0 || /* those that clash with this */
1301 bitVectBitValue(_G.totRegAssigned,i) == 0) /* and are still assigned to registers */
1304 assert (clr = hTabItemWithKey(liveRanges,i));
1306 /* mark these registers as used */
1307 for (k = 0 ; k < clr->nRegs ; k++ )
1308 useReg(clr->regs[k]);
1311 if (willCauseSpill(sym->nRegs,sym->regType)) {
1312 /* NOPE :( clear all registers & and continue */
1317 /* THERE IS HOPE !!!! */
1318 for (i=0; i < sym->nRegs ; i++ ) {
1319 if (sym->regType == REG_PTR)
1320 sym->regs[i] = getRegPtrNoSpil ();
1322 sym->regs[i] = getRegGprNoSpil ();
1325 /* for all its definitions check if the registers
1326 allocated needs positioning NOTE: we can position
1327 only ONCE if more than One positioning required
1330 for (i = 0 ; i < sym->defs->size ; i++ ) {
1331 if (bitVectBitValue(sym->defs,i)) {
1333 if (!(ic = hTabItemWithKey(iCodehTab,i))) continue ;
1334 if (SKIP_IC(ic)) continue;
1335 assert(isSymbolEqual(sym,OP_SYMBOL(IC_RESULT(ic)))); /* just making sure */
1336 /* if left is assigned to registers */
1337 if (IS_SYMOP(IC_LEFT(ic)) &&
1338 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_LEFT(ic))->key)) {
1339 pdone += positionRegs(sym,OP_SYMBOL(IC_LEFT(ic)));
1341 if (IS_SYMOP(IC_RIGHT(ic)) &&
1342 bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_RIGHT(ic))->key)) {
1343 pdone += positionRegs(sym,OP_SYMBOL(IC_RIGHT(ic)));
1345 if (pdone > 1) break;
1348 /* had to position more than once GIVE UP */
1350 /* UNDO all the changes we made to try this */
1352 for (i=0; i < sym->nRegs ; i++ ) {
1353 sym->regs[i] = NULL;
1356 printf("Fill Gap gave up due to positioning for %s in function %s\n",sym->name, currFunc ? currFunc->name : "UNKNOWN");
1359 printf("FILLED GAP for %s in function %s\n",sym->name, currFunc ? currFunc->name : "UNKNOWN");
1360 _G.totRegAssigned = bitVectSetBit(_G.totRegAssigned,sym->key);
1361 sym->isspilt = sym->spillA = 0 ;
1362 sym->usl.spillLoc->allocreq--;
1367 /*-----------------------------------------------------------------*/
1368 /* rUmaskForOp :- returns register mask for an operand */
1369 /*-----------------------------------------------------------------*/
1371 rUmaskForOp (operand * op)
1377 /* only temporaries are assigned registers */
1381 sym = OP_SYMBOL (op);
1383 /* if spilt or no registers assigned to it
1385 if (sym->isspilt || !sym->nRegs)
1388 rumask = newBitVect (ds390_nRegs);
1390 for (j = 0; j < sym->nRegs; j++)
1392 rumask = bitVectSetBit (rumask,
1393 sym->regs[j]->rIdx);
1399 /*-----------------------------------------------------------------*/
1400 /* regsUsedIniCode :- returns bit vector of registers used in iCode */
1401 /*-----------------------------------------------------------------*/
1403 regsUsedIniCode (iCode * ic)
1405 bitVect *rmask = newBitVect (ds390_nRegs);
1407 /* do the special cases first */
1410 rmask = bitVectUnion (rmask,
1411 rUmaskForOp (IC_COND (ic)));
1415 /* for the jumptable */
1416 if (ic->op == JUMPTABLE)
1418 rmask = bitVectUnion (rmask,
1419 rUmaskForOp (IC_JTCOND (ic)));
1424 /* of all other cases */
1426 rmask = bitVectUnion (rmask,
1427 rUmaskForOp (IC_LEFT (ic)));
1431 rmask = bitVectUnion (rmask,
1432 rUmaskForOp (IC_RIGHT (ic)));
1435 rmask = bitVectUnion (rmask,
1436 rUmaskForOp (IC_RESULT (ic)));
1442 /*-----------------------------------------------------------------*/
1443 /* createRegMask - for each instruction will determine the regsUsed */
1444 /*-----------------------------------------------------------------*/
1446 createRegMask (eBBlock ** ebbs, int count)
1450 /* for all blocks */
1451 for (i = 0; i < count; i++)
1455 if (ebbs[i]->noPath &&
1456 (ebbs[i]->entryLabel != entryLabel &&
1457 ebbs[i]->entryLabel != returnLabel))
1460 /* for all instructions */
1461 for (ic = ebbs[i]->sch; ic; ic = ic->next)
1466 if (SKIP_IC2 (ic) || !ic->rlive)
1469 /* first mark the registers used in this
1471 ic->rUsed = regsUsedIniCode (ic);
1472 _G.funcrUsed = bitVectUnion (_G.funcrUsed, ic->rUsed);
1474 /* now create the register mask for those
1475 registers that are in use : this is a
1476 super set of ic->rUsed */
1477 ic->rMask = newBitVect (ds390_nRegs + 1);
1479 /* for all live Ranges alive at this point */
1480 for (j = 1; j < ic->rlive->size; j++)
1485 /* if not alive then continue */
1486 if (!bitVectBitValue (ic->rlive, j))
1489 /* find the live range we are interested in */
1490 if (!(sym = hTabItemWithKey (liveRanges, j)))
1492 werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
1493 "createRegMask cannot find live range");
1497 /* special case for ruonly */
1498 if (sym->ruonly && sym->liveFrom != sym->liveTo) {
1499 int size = getSize(sym->type);
1501 for (k = 0 ; k < size; k++ )
1502 ic->rMask = bitVectSetBit (ic->rMask, j++);
1505 /* if no register assigned to it */
1506 if (!sym->nRegs || sym->isspilt)
1509 /* for all the registers allocated to it */
1510 for (k = 0; k < sym->nRegs; k++)
1513 bitVectSetBit (ic->rMask, sym->regs[k]->rIdx);
1519 /*-----------------------------------------------------------------*/
1520 /* rematStr - returns the rematerialized string for a remat var */
1521 /*-----------------------------------------------------------------*/
1523 rematStr (symbol * sym)
1526 iCode *ic = sym->rematiCode;
1531 /* if plus or minus print the right hand side */
1532 if (ic->op == '+' || ic->op == '-')
1534 sprintf (s, "0x%04x %c ", (int) operandLitValue (IC_RIGHT (ic)),
1537 ic = OP_SYMBOL (IC_LEFT (ic))->rematiCode;
1540 /* cast then continue */
1541 if (IS_CAST_ICODE(ic)) {
1542 ic = OP_SYMBOL (IC_RIGHT (ic))->rematiCode;
1545 /* we reached the end */
1546 sprintf (s, "%s", OP_SYMBOL (IC_LEFT (ic))->rname);
1553 /*-----------------------------------------------------------------*/
1554 /* regTypeNum - computes the type & number of registers required */
1555 /*-----------------------------------------------------------------*/
1563 /* for each live range do */
1564 for (sym = hTabFirstItem (liveRanges, &k); sym;
1565 sym = hTabNextItem (liveRanges, &k))
1568 /* if used zero times then no registers needed */
1569 if ((sym->liveTo - sym->liveFrom) == 0)
1573 /* if the live range is a temporary */
1577 /* if the type is marked as a conditional */
1578 if (sym->regType == REG_CND)
1581 /* if used in return only then we don't
1583 if (sym->ruonly || sym->accuse)
1585 if (IS_AGGREGATE (sym->type) || sym->isptr)
1586 sym->type = aggrToPtr (sym->type, FALSE);
1590 /* if the symbol has only one definition &
1591 that definition is a get_pointer and the
1592 pointer we are getting is rematerializable and
1595 if (bitVectnBitsOn (sym->defs) == 1 &&
1596 (ic = hTabItemWithKey (iCodehTab,
1597 bitVectFirstBit (sym->defs))) &&
1600 !IS_BITVAR (sym->etype))
1604 /* if remat in data space */
1605 if (OP_SYMBOL (IC_LEFT (ic))->remat &&
1606 !IS_CAST_ICODE(OP_SYMBOL (IC_LEFT (ic))->rematiCode) &&
1607 DCL_TYPE (aggrToPtr (sym->type, FALSE)) == POINTER)
1610 /* create a psuedo symbol & force a spil */
1611 symbol *psym = newSymbol (rematStr (OP_SYMBOL (IC_LEFT (ic))), 1);
1612 psym->type = sym->type;
1613 psym->etype = sym->etype;
1614 strcpy (psym->rname, psym->name);
1616 sym->usl.spillLoc = psym;
1620 /* if in data space or idata space then try to
1621 allocate pointer register */
1625 /* if not then we require registers */
1626 sym->nRegs = ((IS_AGGREGATE (sym->type) || sym->isptr) ?
1627 getSize (sym->type = aggrToPtr (sym->type, FALSE)) :
1628 getSize (sym->type));
1632 fprintf (stderr, "allocated more than 4 or 0 registers for type ");
1633 printTypeChain (sym->type, stderr);
1634 fprintf (stderr, "\n");
1637 /* determine the type of register required */
1638 if (sym->nRegs == 1 &&
1639 IS_PTR (sym->type) &&
1641 sym->regType = REG_PTR;
1643 sym->regType = REG_GPR;
1647 /* for the first run we don't provide */
1648 /* registers for true symbols we will */
1649 /* see how things go */
1655 /*-----------------------------------------------------------------*/
1656 /* freeAllRegs - mark all registers as free */
1657 /*-----------------------------------------------------------------*/
1663 for (i = 0; i < ds390_nRegs; i++)
1664 regs390[i].isFree = 1;
1667 /*-----------------------------------------------------------------*/
1668 /* deallocStackSpil - this will set the stack pointer back */
1669 /*-----------------------------------------------------------------*/
1671 DEFSETFUNC (deallocStackSpil)
1679 /*-----------------------------------------------------------------*/
1680 /* farSpacePackable - returns the packable icode for far variables */
1681 /*-----------------------------------------------------------------*/
1683 farSpacePackable (iCode * ic)
1687 /* go thru till we find a definition for the
1688 symbol on the right */
1689 for (dic = ic->prev; dic; dic = dic->prev)
1692 /* if the definition is a call then no */
1693 if ((dic->op == CALL || dic->op == PCALL) &&
1694 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1699 /* if shift by unknown amount then not */
1700 if ((dic->op == LEFT_OP || dic->op == RIGHT_OP) &&
1701 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1704 /* if pointer get and size > 1 */
1705 if (POINTER_GET (dic) &&
1706 getSize (aggrToPtr (operandType (IC_LEFT (dic)), FALSE)) > 1)
1709 if (POINTER_SET (dic) &&
1710 getSize (aggrToPtr (operandType (IC_RESULT (dic)), FALSE)) > 1)
1713 /* if any three is a true symbol in far space */
1714 if (IC_RESULT (dic) &&
1715 IS_TRUE_SYMOP (IC_RESULT (dic)) &&
1716 isOperandInFarSpace (IC_RESULT (dic)))
1719 if (IC_RIGHT (dic) &&
1720 IS_TRUE_SYMOP (IC_RIGHT (dic)) &&
1721 isOperandInFarSpace (IC_RIGHT (dic)) &&
1722 !isOperandEqual (IC_RIGHT (dic), IC_RESULT (ic)))
1725 if (IC_LEFT (dic) &&
1726 IS_TRUE_SYMOP (IC_LEFT (dic)) &&
1727 isOperandInFarSpace (IC_LEFT (dic)) &&
1728 !isOperandEqual (IC_LEFT (dic), IC_RESULT (ic)))
1731 if (isOperandEqual (IC_RIGHT (ic), IC_RESULT (dic)))
1733 if ((dic->op == LEFT_OP ||
1734 dic->op == RIGHT_OP ||
1736 IS_OP_LITERAL (IC_RIGHT (dic)))
1746 /*-----------------------------------------------------------------*/
1747 /* packRegsForAssign - register reduction for assignment */
1748 /*-----------------------------------------------------------------*/
1750 packRegsForAssign (iCode * ic, eBBlock * ebp)
1754 if (!IS_ITEMP (IC_RIGHT (ic)) ||
1755 OP_SYMBOL (IC_RIGHT (ic))->isind ||
1756 OP_LIVETO (IC_RIGHT (ic)) > ic->seq)
1761 /* if the true symbol is defined in far space or on stack
1762 then we should not since this will increase register pressure */
1764 if (isOperandInFarSpace (IC_RESULT (ic)))
1766 if ((dic = farSpacePackable (ic)))
1772 if (isOperandInFarSpace(IC_RESULT(ic)) && !farSpacePackable(ic)) {
1777 /* find the definition of iTempNN scanning backwards if we find a
1778 a use of the true symbol in before we find the definition then
1780 for (dic = ic->prev; dic; dic = dic->prev)
1782 /* if there is a function call then don't pack it */
1783 if ((dic->op == CALL || dic->op == PCALL))
1792 if (IS_TRUE_SYMOP (IC_RESULT (dic)) &&
1793 IS_OP_VOLATILE (IC_RESULT (dic)))
1799 if (IS_SYMOP (IC_RESULT (dic)) &&
1800 IC_RESULT (dic)->key == IC_RIGHT (ic)->key)
1802 if (POINTER_SET (dic))
1808 if (IS_SYMOP (IC_RIGHT (dic)) &&
1809 (IC_RIGHT (dic)->key == IC_RESULT (ic)->key ||
1810 IC_RIGHT (dic)->key == IC_RIGHT (ic)->key))
1816 if (IS_SYMOP (IC_LEFT (dic)) &&
1817 (IC_LEFT (dic)->key == IC_RESULT (ic)->key ||
1818 IC_LEFT (dic)->key == IC_RIGHT (ic)->key))
1824 if (POINTER_SET (dic) &&
1825 IC_RESULT (dic)->key == IC_RESULT (ic)->key)
1833 return 0; /* did not find */
1835 /* if the result is on stack or iaccess then it must be
1836 the same atleast one of the operands */
1837 if (OP_SYMBOL (IC_RESULT (ic))->onStack ||
1838 OP_SYMBOL (IC_RESULT (ic))->iaccess)
1841 /* the operation has only one symbol
1842 operator then we can pack */
1843 if ((IC_LEFT (dic) && !IS_SYMOP (IC_LEFT (dic))) ||
1844 (IC_RIGHT (dic) && !IS_SYMOP (IC_RIGHT (dic))))
1847 if (!((IC_LEFT (dic) &&
1848 IC_RESULT (ic)->key == IC_LEFT (dic)->key) ||
1850 IC_RESULT (ic)->key == IC_RIGHT (dic)->key)))
1854 /* found the definition */
1855 /* replace the result with the result of */
1856 /* this assignment and remove this assignment */
1857 IC_RESULT (dic) = IC_RESULT (ic);
1859 if (IS_ITEMP (IC_RESULT (dic)) && OP_SYMBOL (IC_RESULT (dic))->liveFrom > dic->seq)
1861 OP_SYMBOL (IC_RESULT (dic))->liveFrom = dic->seq;
1863 /* delete from liverange table also
1864 delete from all the points inbetween and the new
1866 for (sic = dic; sic != ic; sic = sic->next)
1868 bitVectUnSetBit (sic->rlive, IC_RESULT (ic)->key);
1869 if (IS_ITEMP (IC_RESULT (dic)))
1870 bitVectSetBit (sic->rlive, IC_RESULT (dic)->key);
1873 remiCodeFromeBBlock (ebp, ic);
1874 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
1875 OP_DEFS (IC_RESULT (dic)) = bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
1880 /*-----------------------------------------------------------------*/
1881 /* findAssignToSym : scanning backwards looks for first assig found */
1882 /*-----------------------------------------------------------------*/
1884 findAssignToSym (operand * op, iCode * ic)
1888 for (dic = ic->prev; dic; dic = dic->prev)
1891 /* if definition by assignment */
1892 if (dic->op == '=' &&
1893 !POINTER_SET (dic) &&
1894 IC_RESULT (dic)->key == op->key
1895 /* && IS_TRUE_SYMOP(IC_RIGHT(dic)) */
1899 /* we are interested only if defined in far space */
1900 /* or in stack space in case of + & - */
1902 /* if assigned to a non-symbol then return
1904 if (!IS_SYMOP (IC_RIGHT (dic)))
1907 /* if the symbol is in far space then
1909 if (isOperandInFarSpace (IC_RIGHT (dic)))
1912 /* for + & - operations make sure that
1913 if it is on the stack it is the same
1914 as one of the three operands */
1915 if ((ic->op == '+' || ic->op == '-') &&
1916 OP_SYMBOL (IC_RIGHT (dic))->onStack)
1919 if (IC_RESULT (ic)->key != IC_RIGHT (dic)->key &&
1920 IC_LEFT (ic)->key != IC_RIGHT (dic)->key &&
1921 IC_RIGHT (ic)->key != IC_RIGHT (dic)->key)
1929 /* if we find an usage then we cannot delete it */
1930 if (IC_LEFT (dic) && IC_LEFT (dic)->key == op->key)
1933 if (IC_RIGHT (dic) && IC_RIGHT (dic)->key == op->key)
1936 if (POINTER_SET (dic) && IC_RESULT (dic)->key == op->key)
1940 /* now make sure that the right side of dic
1941 is not defined between ic & dic */
1944 iCode *sic = dic->next;
1946 for (; sic != ic; sic = sic->next)
1947 if (IC_RESULT (sic) &&
1948 IC_RESULT (sic)->key == IC_RIGHT (dic)->key)
1957 /*-----------------------------------------------------------------*/
1958 /* packRegsForSupport :- reduce some registers for support calls */
1959 /*-----------------------------------------------------------------*/
1961 packRegsForSupport (iCode * ic, eBBlock * ebp)
1964 /* for the left & right operand :- look to see if the
1965 left was assigned a true symbol in far space in that
1966 case replace them */
1967 if (IS_ITEMP (IC_LEFT (ic)) &&
1968 OP_SYMBOL (IC_LEFT (ic))->liveTo <= ic->seq)
1970 iCode *dic = findAssignToSym (IC_LEFT (ic), ic);
1976 /* found it we need to remove it from the
1978 for (sic = dic; sic != ic; sic = sic->next)
1979 bitVectUnSetBit (sic->rlive, IC_LEFT (ic)->key);
1981 IC_LEFT (ic)->operand.symOperand =
1982 IC_RIGHT (dic)->operand.symOperand;
1983 IC_LEFT (ic)->key = IC_RIGHT (dic)->operand.symOperand->key;
1984 remiCodeFromeBBlock (ebp, dic);
1985 hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
1989 /* do the same for the right operand */
1992 IS_ITEMP (IC_RIGHT (ic)) &&
1993 OP_SYMBOL (IC_RIGHT (ic))->liveTo <= ic->seq)
1995 iCode *dic = findAssignToSym (IC_RIGHT (ic), ic);
2001 /* if this is a subtraction & the result
2002 is a true symbol in far space then don't pack */
2003 if (ic->op == '-' && IS_TRUE_SYMOP (IC_RESULT (dic)))
2005 sym_link *etype = getSpec (operandType (IC_RESULT (dic)));
2006 if (IN_FARSPACE (SPEC_OCLS (etype)))
2009 /* found it we need to remove it from the
2011 for (sic = dic; sic != ic; sic = sic->next)
2012 bitVectUnSetBit (sic->rlive, IC_RIGHT (ic)->key);
2014 IC_RIGHT (ic)->operand.symOperand =
2015 IC_RIGHT (dic)->operand.symOperand;
2016 IC_RIGHT (ic)->key = IC_RIGHT (dic)->operand.symOperand->key;
2018 remiCodeFromeBBlock (ebp, dic);
2019 hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
2026 #define IS_OP_RUONLY(x) (x && IS_SYMOP(x) && OP_SYMBOL(x)->ruonly)
2029 /*-----------------------------------------------------------------*/
2030 /* packRegsDPTRuse : - will reduce some registers for single Use */
2031 /*-----------------------------------------------------------------*/
2033 packRegsDPTRuse (iCode * lic, operand * op, eBBlock * ebp)
2035 /* go thru entire liveRange of this variable & check for
2036 other possible usage of DPTR , if we don't find it the
2037 assign this to DPTR (ruonly)
2042 sym_link *type, *etype;
2044 if (!IS_SYMOP(op)) return NULL;
2045 if (OP_SYMBOL(op)->remat || OP_SYMBOL(op)->ruonly) return NULL;
2047 /* first check if any overlapping liverange has already been
2049 if (OP_SYMBOL(op)->clashes) {
2050 for (i = 0 ; i < OP_SYMBOL(op)->clashes->size ; i++ ) {
2051 if (bitVectBitValue(OP_SYMBOL(op)->clashes,i)) {
2052 sym = hTabItemWithKey(liveRanges,i);
2053 if (sym->ruonly) return NULL ;
2058 /* no then go thru this guys live range */
2059 dic = ic = hTabFirstItemWK(iCodeSeqhTab,OP_SYMBOL(op)->liveFrom);
2060 for (; ic && ic->seq <= OP_SYMBOL(op)->liveTo;
2061 ic = hTabNextItem(iCodeSeqhTab,&key)) {
2063 /* if PCALL cannot be sure give up */
2064 if (ic->op == PCALL) return NULL;
2066 /* if CALL then make sure it is VOID || return value not used */
2067 if (ic->op == CALL) {
2068 if (OP_SYMBOL(IC_RESULT(ic))->liveTo ==
2069 OP_SYMBOL(IC_RESULT(ic))->liveFrom) continue ;
2070 etype = getSpec(type = operandType(IC_RESULT(ic)));
2071 if (getSize(type) == 0) continue ;
2075 /* special case of add with a [remat] */
2076 if (ic->op == '+' &&
2077 OP_SYMBOL(IC_LEFT(ic))->remat &&
2078 !isOperandInFarSpace(IC_RIGHT(ic))) continue ;
2082 if (POINTER_GET(ic) && isOperandEqual(IC_RESULT(ic),op) &&
2083 getSize(operandType(IC_LEFT(ic))) > 1) return NULL ;
2085 if (POINTER_SET(ic) && isOperandEqual(IC_RIGHT(ic),op) &&
2086 getSize(operandType(IC_RESULT(ic))) > 1) return NULL;
2089 if (IC_RESULT(ic) && IS_SYMOP(IC_RESULT(ic)) &&
2090 !isOperandEqual(IC_RESULT(ic),op) &&
2091 (isOperandInFarSpace(IC_RESULT(ic)) ||
2092 OP_SYMBOL(IC_RESULT(ic))->ruonly ||
2093 OP_SYMBOL(IC_RESULT(ic))->onStack)) return NULL;
2095 if (IC_RIGHT(ic) && IS_SYMOP(IC_RIGHT(ic)) &&
2096 !isOperandEqual(IC_RIGHT(ic),op) &&
2097 (OP_SYMBOL(IC_RIGHT(ic))->liveTo > ic->seq ||
2098 IS_TRUE_SYMOP(IC_RIGHT(ic)) ||
2099 OP_SYMBOL(IC_RIGHT(ic))->ruonly) &&
2100 (isOperandInFarSpace(IC_RIGHT(ic)) ||
2101 OP_SYMBOL(IC_RIGHT(ic))->onStack)) return NULL;
2103 if (IC_LEFT(ic) && IS_SYMOP(IC_LEFT(ic)) &&
2104 !isOperandEqual(IC_LEFT(ic),op) &&
2105 (OP_SYMBOL(IC_LEFT(ic))->liveTo > ic->seq ||
2106 IS_TRUE_SYMOP(IC_LEFT(ic)) ||
2107 OP_SYMBOL(IC_LEFT(ic))->ruonly) &&
2108 (isOperandInFarSpace(IC_LEFT(ic)) ||
2109 OP_SYMBOL(IC_LEFT(ic))->onStack)) return NULL;
2111 if (IC_LEFT(ic) && IC_RIGHT(ic) &&
2112 IS_ITEMP(IC_LEFT(ic)) && IS_ITEMP(IC_RIGHT(ic)) &&
2113 isOperandInFarSpace(IC_LEFT(ic)) && isOperandInFarSpace(IC_RIGHT(ic)))
2116 OP_SYMBOL(op)->ruonly = 1;
2120 /*-----------------------------------------------------------------*/
2121 /* isBitwiseOptimizable - requirements of JEAN LOUIS VERN */
2122 /*-----------------------------------------------------------------*/
2124 isBitwiseOptimizable (iCode * ic)
2126 sym_link *ltype = getSpec (operandType (IC_LEFT (ic)));
2127 sym_link *rtype = getSpec (operandType (IC_RIGHT (ic)));
2129 /* bitwise operations are considered optimizable
2130 under the following conditions (Jean-Louis VERN)
2142 if ( IS_LITERAL (rtype) ||
2143 (IS_BITVAR (ltype) && IN_BITSPACE (SPEC_OCLS (ltype))))
2149 /*-----------------------------------------------------------------*/
2150 /* packRegsForAccUse - pack registers for acc use */
2151 /*-----------------------------------------------------------------*/
2153 packRegsForAccUse (iCode * ic)
2157 /* if + or - then it has to be one byte result */
2158 if ((ic->op == '+' || ic->op == '-')
2159 && getSize (operandType (IC_RESULT (ic))) > 1)
2162 /* if shift operation make sure right side is not a literal */
2163 if (ic->op == RIGHT_OP &&
2164 (isOperandLiteral (IC_RIGHT (ic)) ||
2165 getSize (operandType (IC_RESULT (ic))) > 1))
2168 if (ic->op == LEFT_OP &&
2169 (isOperandLiteral (IC_RIGHT (ic)) ||
2170 getSize (operandType (IC_RESULT (ic))) > 1))
2173 if (IS_BITWISE_OP (ic) &&
2174 getSize (operandType (IC_RESULT (ic))) > 1)
2178 /* has only one definition */
2179 if (bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) > 1)
2182 /* has only one use */
2183 if (bitVectnBitsOn (OP_USES (IC_RESULT (ic))) > 1)
2186 /* and the usage immediately follows this iCode */
2187 if (!(uic = hTabItemWithKey (iCodehTab,
2188 bitVectFirstBit (OP_USES (IC_RESULT (ic))))))
2191 if (ic->next != uic)
2194 /* if it is a conditional branch then we definitely can */
2198 if (uic->op == JUMPTABLE)
2201 /* if the usage is not is an assignment
2202 or an arithmetic / bitwise / shift operation then not */
2203 if (POINTER_SET (uic) &&
2204 getSize (aggrToPtr (operandType (IC_RESULT (uic)), FALSE)) > 1)
2207 if (uic->op != '=' &&
2208 !IS_ARITHMETIC_OP (uic) &&
2209 !IS_BITWISE_OP (uic) &&
2210 uic->op != LEFT_OP &&
2211 uic->op != RIGHT_OP)
2214 /* if used in ^ operation then make sure right is not a
2216 if (uic->op == '^' && isOperandLiteral (IC_RIGHT (uic)))
2219 /* if shift operation make sure right side is not a literal */
2220 if (uic->op == RIGHT_OP &&
2221 (isOperandLiteral (IC_RIGHT (uic)) ||
2222 getSize (operandType (IC_RESULT (uic))) > 1))
2225 if (uic->op == LEFT_OP &&
2226 (isOperandLiteral (IC_RIGHT (uic)) ||
2227 getSize (operandType (IC_RESULT (uic))) > 1))
2230 /* make sure that the result of this icode is not on the
2231 stack, since acc is used to compute stack offset */
2232 if (IS_TRUE_SYMOP (IC_RESULT (uic)) &&
2233 OP_SYMBOL (IC_RESULT (uic))->onStack)
2236 /* if either one of them in far space then we cannot */
2237 if ((IS_TRUE_SYMOP (IC_LEFT (uic)) &&
2238 isOperandInFarSpace (IC_LEFT (uic))) ||
2239 (IS_TRUE_SYMOP (IC_RIGHT (uic)) &&
2240 isOperandInFarSpace (IC_RIGHT (uic))))
2243 /* if the usage has only one operand then we can */
2244 if (IC_LEFT (uic) == NULL ||
2245 IC_RIGHT (uic) == NULL)
2248 /* make sure this is on the left side if not
2249 a '+' since '+' is commutative */
2250 if (ic->op != '+' &&
2251 IC_LEFT (uic)->key != IC_RESULT (ic)->key)
2255 // this is too dangerous and need further restrictions
2258 /* if one of them is a literal then we can */
2259 if ((IC_LEFT (uic) && IS_OP_LITERAL (IC_LEFT (uic))) ||
2260 (IC_RIGHT (uic) && IS_OP_LITERAL (IC_RIGHT (uic))))
2262 OP_SYMBOL (IC_RESULT (ic))->accuse = 1;
2267 /* if the other one is not on stack then we can */
2268 if (IC_LEFT (uic)->key == IC_RESULT (ic)->key &&
2269 (IS_ITEMP (IC_RIGHT (uic)) ||
2270 (IS_TRUE_SYMOP (IC_RIGHT (uic)) &&
2271 !OP_SYMBOL (IC_RIGHT (uic))->onStack)))
2274 if (IC_RIGHT (uic)->key == IC_RESULT (ic)->key &&
2275 (IS_ITEMP (IC_LEFT (uic)) ||
2276 (IS_TRUE_SYMOP (IC_LEFT (uic)) &&
2277 !OP_SYMBOL (IC_LEFT (uic))->onStack)))
2283 OP_SYMBOL (IC_RESULT (ic))->accuse = 1;
2288 /*-----------------------------------------------------------------*/
2289 /* packForPush - hueristics to reduce iCode for pushing */
2290 /*-----------------------------------------------------------------*/
2292 packForPush (iCode * ic, eBBlock * ebp)
2297 if (ic->op != IPUSH || !IS_ITEMP (IC_LEFT (ic)))
2300 /* must have only definition & one usage */
2301 if (bitVectnBitsOn (OP_DEFS (IC_LEFT (ic))) != 1 ||
2302 bitVectnBitsOn (OP_USES (IC_LEFT (ic))) != 1)
2305 /* find the definition */
2306 if (!(dic = hTabItemWithKey (iCodehTab,
2307 bitVectFirstBit (OP_DEFS (IC_LEFT (ic))))))
2310 if (dic->op != '=' || POINTER_SET (dic))
2313 /* make sure the right side does not have any definitions
2315 dbv = OP_DEFS(IC_RIGHT(dic));
2316 for (lic = ic; lic && lic != dic ; lic = lic->prev) {
2317 if (bitVectBitValue(dbv,lic->key)) return ;
2319 /* make sure they have the same type */
2321 sym_link *itype=operandType(IC_LEFT(ic));
2322 sym_link *ditype=operandType(IC_RIGHT(dic));
2324 if (SPEC_USIGN(itype)!=SPEC_USIGN(ditype) ||
2325 SPEC_LONG(itype)!=SPEC_LONG(ditype))
2328 /* extend the live range of replaced operand if needed */
2329 if (OP_SYMBOL(IC_RIGHT(dic))->liveTo < ic->seq) {
2330 OP_SYMBOL(IC_RIGHT(dic))->liveTo = ic->seq;
2332 /* we now we know that it has one & only one def & use
2333 and the that the definition is an assignment */
2334 IC_LEFT (ic) = IC_RIGHT (dic);
2336 remiCodeFromeBBlock (ebp, dic);
2337 hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
2340 /*-----------------------------------------------------------------*/
2341 /* packRegisters - does some transformations to reduce register */
2343 /*-----------------------------------------------------------------*/
2345 packRegisters (eBBlock * ebp)
2355 /* look for assignments of the form */
2356 /* iTempNN = TRueSym (someoperation) SomeOperand */
2358 /* TrueSym := iTempNN:1 */
2359 for (ic = ebp->sch; ic; ic = ic->next)
2363 /* find assignment of the form TrueSym := iTempNN:1 */
2364 if (ic->op == '=' && !POINTER_SET (ic))
2365 change += packRegsForAssign (ic, ebp);
2372 for (ic = ebp->sch; ic; ic = ic->next)
2375 /* if this is an itemp & result of a address of a true sym
2376 then mark this as rematerialisable */
2377 if (ic->op == ADDRESS_OF &&
2378 IS_ITEMP (IC_RESULT (ic)) &&
2379 IS_TRUE_SYMOP (IC_LEFT (ic)) &&
2380 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1 &&
2381 !OP_SYMBOL (IC_LEFT (ic))->onStack)
2384 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2385 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2386 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2390 /* if straight assignment then carry remat flag if
2391 this is the only definition */
2392 if (ic->op == '=' &&
2393 !POINTER_SET (ic) &&
2394 IS_SYMOP (IC_RIGHT (ic)) &&
2395 OP_SYMBOL (IC_RIGHT (ic))->remat &&
2396 !IS_CAST_ICODE(OP_SYMBOL (IC_RIGHT (ic))->rematiCode) &&
2397 bitVectnBitsOn (OP_SYMBOL (IC_RESULT (ic))->defs) <= 1)
2400 OP_SYMBOL (IC_RESULT (ic))->remat =
2401 OP_SYMBOL (IC_RIGHT (ic))->remat;
2402 OP_SYMBOL (IC_RESULT (ic))->rematiCode =
2403 OP_SYMBOL (IC_RIGHT (ic))->rematiCode;
2406 /* if cast to a generic pointer & the pointer being
2407 cast is remat, then we can remat this cast as well */
2408 if (ic->op == CAST &&
2409 IS_SYMOP(IC_RIGHT(ic)) &&
2410 OP_SYMBOL(IC_RIGHT(ic))->remat ) {
2411 sym_link *to_type = operandType(IC_LEFT(ic));
2412 sym_link *from_type = operandType(IC_RIGHT(ic));
2413 if (IS_GENPTR(to_type) && IS_PTR(from_type)) {
2414 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2415 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2416 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2420 /* if this is a +/- operation with a rematerizable
2421 then mark this as rematerializable as well */
2422 if ((ic->op == '+' || ic->op == '-') &&
2423 (IS_SYMOP (IC_LEFT (ic)) &&
2424 IS_ITEMP (IC_RESULT (ic)) &&
2425 OP_SYMBOL (IC_LEFT (ic))->remat &&
2426 (!IS_SYMOP (IC_RIGHT (ic)) || !IS_CAST_ICODE(OP_SYMBOL (IC_RIGHT (ic))->rematiCode)) &&
2427 bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1 &&
2428 IS_OP_LITERAL (IC_RIGHT (ic))))
2431 //int i = operandLitValue(IC_RIGHT(ic));
2432 OP_SYMBOL (IC_RESULT (ic))->remat = 1;
2433 OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
2434 OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
2437 /* mark the pointer usages */
2438 if (POINTER_SET (ic))
2439 OP_SYMBOL (IC_RESULT (ic))->uptr = 1;
2441 if (POINTER_GET (ic))
2442 OP_SYMBOL (IC_LEFT (ic))->uptr = 1;
2446 /* if we are using a symbol on the stack
2447 then we should say ds390_ptrRegReq */
2448 if (ic->op == IFX && IS_SYMOP (IC_COND (ic)))
2449 ds390_ptrRegReq += ((OP_SYMBOL (IC_COND (ic))->onStack ? !options.stack10bit : 0) +
2450 OP_SYMBOL (IC_COND (ic))->iaccess);
2451 else if (ic->op == JUMPTABLE && IS_SYMOP (IC_JTCOND (ic)))
2452 ds390_ptrRegReq += ((OP_SYMBOL (IC_JTCOND (ic))->onStack ? !options.stack10bit : 0) +
2453 OP_SYMBOL (IC_JTCOND (ic))->iaccess);
2456 if (IS_SYMOP (IC_LEFT (ic)))
2457 ds390_ptrRegReq += ((OP_SYMBOL (IC_LEFT (ic))->onStack ? !options.stack10bit : 0) +
2458 OP_SYMBOL (IC_LEFT (ic))->iaccess);
2459 if (IS_SYMOP (IC_RIGHT (ic)))
2460 ds390_ptrRegReq += ((OP_SYMBOL (IC_RIGHT (ic))->onStack ? !options.stack10bit : 0) +
2461 OP_SYMBOL (IC_RIGHT (ic))->iaccess);
2462 if (IS_SYMOP (IC_RESULT (ic)))
2463 ds390_ptrRegReq += ((OP_SYMBOL (IC_RESULT (ic))->onStack ? !options.stack10bit : 0) +
2464 OP_SYMBOL (IC_RESULT (ic))->iaccess);
2469 /* if the condition of an if instruction
2470 is defined in the previous instruction then
2471 mark the itemp as a conditional */
2472 if ((IS_CONDITIONAL (ic) ||
2473 (IS_BITWISE_OP(ic) && isBitwiseOptimizable(ic))) &&
2474 ic->next && ic->next->op == IFX &&
2475 isOperandEqual (IC_RESULT (ic), IC_COND (ic->next)) &&
2476 OP_SYMBOL (IC_RESULT (ic))->liveTo <= ic->next->seq)
2479 OP_SYMBOL (IC_RESULT (ic))->regType = REG_CND;
2483 /* if the condition of an if instruction
2484 is defined in the previous instruction and
2485 this is the only usage then
2486 mark the itemp as a conditional */
2487 if ((IS_CONDITIONAL (ic) ||
2488 (IS_BITWISE_OP(ic) && isBitwiseOptimizable (ic))) &&
2489 ic->next && ic->next->op == IFX &&
2490 bitVectnBitsOn (OP_USES(IC_RESULT(ic)))==1 &&
2491 isOperandEqual (IC_RESULT (ic), IC_COND (ic->next)) &&
2492 OP_SYMBOL (IC_RESULT (ic))->liveTo <= ic->next->seq)
2494 OP_SYMBOL (IC_RESULT (ic))->regType = REG_CND;
2499 /* reduce for support function calls */
2500 if (ic->supportRtn || ic->op == '+' || ic->op == '-')
2501 packRegsForSupport (ic, ebp);
2503 /* some cases the redundant moves can
2504 can be eliminated for return statements */
2505 if ((ic->op == RETURN || ic->op == SEND) &&
2506 !isOperandInFarSpace (IC_LEFT (ic)) &&
2509 packRegsDPTRuse (ic, IC_LEFT (ic), ebp);
2512 if ((ic->op == CALL && getSize(operandType(IC_RESULT(ic))) <= 4)) {
2513 packRegsDPTRuse (ic, IC_RESULT (ic), ebp);
2516 /* if pointer set & left has a size more than
2517 one and right is not in far space */
2518 if (POINTER_SET (ic) &&
2519 !isOperandInFarSpace (IC_RIGHT (ic)) &&
2520 !OP_SYMBOL (IC_RESULT (ic))->remat &&
2521 !IS_OP_RUONLY (IC_RIGHT (ic)) &&
2522 getSize (aggrToPtr (operandType (IC_RESULT (ic)), FALSE)) > 1) {
2524 packRegsDPTRuse (ic, IC_RESULT (ic), ebp);
2527 /* if pointer get */
2528 if (POINTER_GET (ic) &&
2529 !isOperandInFarSpace (IC_RESULT (ic)) &&
2530 !OP_SYMBOL (IC_LEFT (ic))->remat &&
2531 !IS_OP_RUONLY (IC_RESULT (ic)) &&
2532 getSize (aggrToPtr (operandType (IC_LEFT (ic)), FALSE)) > 1) {
2534 packRegsDPTRuse (ic, IC_LEFT (ic), ebp);
2537 /* if this is cast for intergral promotion then
2538 check if only use of the definition of the
2539 operand being casted/ if yes then replace
2540 the result of that arithmetic operation with
2541 this result and get rid of the cast */
2544 sym_link *fromType = operandType (IC_RIGHT (ic));
2545 sym_link *toType = operandType (IC_LEFT (ic));
2547 if (IS_INTEGRAL (fromType) && IS_INTEGRAL (toType) &&
2548 getSize (fromType) != getSize (toType) &&
2549 SPEC_USIGN (fromType) == SPEC_USIGN (toType))
2552 iCode *dic = packRegsDPTRuse (ic, IC_RIGHT (ic), ebp);
2555 if (IS_ARITHMETIC_OP (dic))
2557 IC_RESULT (dic) = IC_RESULT (ic);
2558 remiCodeFromeBBlock (ebp, ic);
2559 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
2560 OP_DEFS (IC_RESULT (dic)) = bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
2564 OP_SYMBOL (IC_RIGHT (ic))->ruonly = 0;
2570 /* if the type from and type to are the same
2571 then if this is the only use then packit */
2572 if (compareType (operandType (IC_RIGHT (ic)),
2573 operandType (IC_LEFT (ic))) == 1)
2575 iCode *dic = packRegsDPTRuse (ic, IC_RIGHT (ic), ebp);
2578 IC_RESULT (dic) = IC_RESULT (ic);
2579 remiCodeFromeBBlock (ebp, ic);
2580 hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
2581 OP_DEFS (IC_RESULT (dic)) = bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
2589 iTempNN := (some variable in farspace) V1
2594 if (ic->op == IPUSH)
2596 packForPush (ic, ebp);
2600 /* pack registers for accumulator use, when the
2601 result of an arithmetic or bit wise operation
2602 has only one use, that use is immediately following
2603 the defintion and the using iCode has only one
2604 operand or has two operands but one is literal &
2605 the result of that operation is not on stack then
2606 we can leave the result of this operation in acc:b
2608 if ((IS_ARITHMETIC_OP (ic)
2609 || IS_CONDITIONAL(ic)
2610 || IS_BITWISE_OP (ic)
2611 || ic->op == LEFT_OP || ic->op == RIGHT_OP || ic->op == CALL
2612 || (ic->op == ADDRESS_OF && isOperandOnStack (IC_LEFT (ic)))
2614 IS_ITEMP (IC_RESULT (ic)) &&
2615 getSize (operandType (IC_RESULT (ic))) <= 2)
2617 packRegsForAccUse (ic);
2622 /*-----------------------------------------------------------------*/
2623 /* assignRegisters - assigns registers to each live range as need */
2624 /*-----------------------------------------------------------------*/
2626 ds390_assignRegisters (eBBlock ** ebbs, int count)
2631 setToNull ((void *) &_G.funcrUsed);
2632 setToNull ((void *) &_G.regAssigned);
2633 setToNull ((void *) &_G.totRegAssigned);
2634 setToNull ((void *) &_G.funcrUsed);
2635 ds390_ptrRegReq = _G.stackExtend = _G.dataExtend = 0;
2637 if (options.model != MODEL_FLAT24) options.stack10bit = 0;
2638 /* change assignments this will remove some
2639 live ranges reducing some register pressure */
2640 for (i = 0; i < count; i++)
2641 packRegisters (ebbs[i]);
2643 if (options.dump_pack)
2644 dumpEbbsToFileExt (DUMP_PACK, ebbs, count);
2646 /* first determine for each live range the number of
2647 registers & the type of registers required for each */
2650 /* and serially allocate registers */
2651 serialRegAssign (ebbs, count);
2658 /* if stack was extended then tell the user */
2661 /* werror(W_TOOMANY_SPILS,"stack", */
2662 /* _G.stackExtend,currFunc->name,""); */
2668 /* werror(W_TOOMANY_SPILS,"data space", */
2669 /* _G.dataExtend,currFunc->name,""); */
2673 /* after that create the register mask
2674 for each of the instruction */
2675 createRegMask (ebbs, count);
2677 /* redo that offsets for stacked automatic variables */
2678 redoStackOffsets ();
2680 if (options.dump_rassgn) {
2681 dumpEbbsToFileExt (DUMP_RASSGN, ebbs, count);
2682 dumpLiveRanges (DUMP_LRANGE, liveRanges);
2685 /* do the overlaysegment stuff SDCCmem.c */
2686 doOverlays (ebbs, count);
2688 /* now get back the chain */
2689 ic = iCodeLabelOptimize (iCodeFromeBBlock (ebbs, count));
2694 /* free up any _G.stackSpil locations allocated */
2695 applyToSet (_G.stackSpil, deallocStackSpil);
2697 setToNull ((void **) &_G.stackSpil);
2698 setToNull ((void **) &_G.spiltSet);
2699 /* mark all registers as free */