1 /*-------------------------------------------------------------------------
2 SDCCcse.c - source file for Common Subexpressions and other utility
4 Written By - Sandeep Dutta . sandeep.dutta@usa.net (1998)
6 This program is free software; you can redistribute it and/or modify it
7 under the terms of the GNU General Public License as published by the
8 Free Software Foundation; either version 2, or (at your option) any
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20 In other words, you are welcome to use, share and improve this program.
21 You are forbidden to forbid anyone else to use, share and improve
22 what you give them. Help stamp out software-hoarding!
23 -------------------------------------------------------------------------*/
28 /*-----------------------------------------------------------------*/
29 /* newCseDef - new cseDef */
30 /*-----------------------------------------------------------------*/
32 newCseDef (operand * sym, iCode * ic)
37 cdp = Safe_alloc (sizeof (cseDef));
48 /*-----------------------------------------------------------------*/
49 /* int isCseDefEqual - two definitions are equal */
50 /*-----------------------------------------------------------------*/
52 isCseDefEqual (void *vsrc, void *vdest)
60 return (src->key == dest->key &&
61 src->diCode == dest->diCode);
65 /*-----------------------------------------------------------------*/
66 /* pcseDef - in the cseDef */
67 /*-----------------------------------------------------------------*/
69 pcseDef (void *item, va_list ap)
77 fprintf (stdout, "**null op**");
78 printOperand (cdp->sym, stdout);
79 icTab = getTableEntry (cdp->diCode->op);
80 icTab->iCodePrint (stdout, cdp->diCode, icTab->printName);
84 void ReplaceOpWithCheaperOp(operand **op, operand *cop) {
86 printf ("ReplaceOpWithCheaperOp %s with %s: ",
87 IS_SYMOP((*op)) ? OP_SYMBOL((*op))->name : "!SYM",
88 IS_SYMOP(cop) ? OP_SYMBOL(cop)->name : "!SYM");
89 // if op is a register equivalent
90 if (IS_ITEMP(cop) && OP_SYMBOL((*op))->isreqv) {
91 operand **rop = &OP_SYMBOL((*op))->usl.spillLoc->reqv;
92 if (isOperandEqual(*rop, *op)) {
95 OP_SYMBOL((*op))->isreqv=0;
96 OP_SYMBOL(cop)->isreqv=1;
106 /*-----------------------------------------------------------------*/
107 /* replaceAllSymBySym - replaces all operands by operand in an */
108 /* instruction chain */
109 /*-----------------------------------------------------------------*/
111 replaceAllSymBySym (iCode * ic, operand * from, operand * to, bitVect ** ndpset)
115 for (lic = ic; lic; lic = lic->next)
119 /* do the special cases first */
123 IC_COND (lic)->key == from->key)
126 bitVectUnSetBit (OP_USES (from), lic->key);
127 OP_USES(to)=bitVectSetBit (OP_USES (to), lic->key);
128 siaddr = IC_COND (lic)->isaddr;
129 IC_COND (lic) = operandFromOperand (to);
130 IC_COND (lic)->isaddr = siaddr;
136 if (lic->op == JUMPTABLE)
139 IC_JTCOND (lic)->key == from->key)
142 bitVectUnSetBit (OP_USES (from), lic->key);
143 OP_USES(to)=bitVectSetBit (OP_USES (to), lic->key);
144 siaddr = IC_COND (lic)->isaddr;
145 IC_JTCOND (lic) = operandFromOperand (to);
146 IC_JTCOND (lic)->isaddr = siaddr;
153 IC_RESULT (lic) && IC_RESULT (lic)->key == from->key)
155 /* maintain du chains */
156 if (POINTER_SET (lic))
158 bitVectUnSetBit (OP_USES (from), lic->key);
159 OP_USES(to)=bitVectSetBit (OP_USES (to), lic->key);
161 /* also check if the "from" was in the non-dominating
162 pointer sets and replace it with "to" in the bitVector */
163 if (bitVectBitValue (*ndpset, from->key))
165 bitVectUnSetBit (*ndpset, from->key);
166 bitVectSetBit (*ndpset, to->key);
172 bitVectUnSetBit (OP_DEFS (from), lic->key);
173 OP_DEFS(to)=bitVectSetBit (OP_DEFS (to), lic->key);
175 siaddr = IC_RESULT (lic)->isaddr;
176 IC_RESULT (lic) = operandFromOperand (to);
177 IC_RESULT (lic)->isaddr = siaddr;
181 IC_RIGHT (lic) && IC_RIGHT (lic)->key == from->key)
183 bitVectUnSetBit (OP_USES (from), lic->key);
184 OP_USES(to)=bitVectSetBit (OP_USES (to), lic->key);
185 siaddr = IC_RIGHT (lic)->isaddr;
186 IC_RIGHT (lic) = operandFromOperand (to);
187 IC_RIGHT (lic)->isaddr = siaddr;
191 IC_LEFT (lic) && IC_LEFT (lic)->key == from->key)
193 bitVectUnSetBit (OP_USES (from), lic->key);
194 OP_USES(to)=bitVectSetBit (OP_USES (to), lic->key);
195 siaddr = IC_LEFT (lic)->isaddr;
196 IC_LEFT (lic) = operandFromOperand (to);
197 IC_LEFT (lic)->isaddr = siaddr;
202 /*-----------------------------------------------------------------*/
203 /* iCodeKeyIs - if the icode keys match then return 1 */
204 /*-----------------------------------------------------------------*/
205 DEFSETFUNC (iCodeKeyIs)
210 if (cdp->diCode->key == key)
216 /*-----------------------------------------------------------------*/
217 /* removeFromInExprs - removes an icode from inexpressions */
218 /*-----------------------------------------------------------------*/
219 DEFSETFUNC (removeFromInExprs)
223 V_ARG (operand *, from);
224 V_ARG (operand *, to);
225 V_ARG (eBBlock *, cbp);
231 deleteItemIf (&ebp->inExprs, iCodeKeyIs, ic->key);
232 if (ebp != cbp && !bitVectBitValue (cbp->domVect, ebp->bbnum))
233 replaceAllSymBySym (ebp->sch, from, to, &ebp->ndompset);
235 applyToSet (ebp->succList, removeFromInExprs, ic, from, to, cbp);
239 /*-----------------------------------------------------------------*/
240 /* isGlobalInNearSpace - return TRUE if valriable is a globalin data */
241 /*-----------------------------------------------------------------*/
243 isGlobalInNearSpace (operand * op)
245 sym_link *type = getSpec (operandType (op));
246 /* this is 8051 specific: optimization
247 suggested by Jean-Louis VERN, with 8051s we have no
248 advantage of putting variables in near space into
250 if (isOperandGlobal (op) && !IN_FARSPACE (SPEC_OCLS (type)) &&
251 IN_DIRSPACE (SPEC_OCLS (type)))
257 /*-----------------------------------------------------------------*/
258 /* findCheaperOp - cseBBlock support routine, will check to see if */
259 /* we have a operand previously defined */
260 /*-----------------------------------------------------------------*/
261 DEFSETFUNC (findCheaperOp)
264 V_ARG (operand *, cop);
265 V_ARG (operand **, opp);
266 V_ARG (int, checkSign);
268 /* if we have already found it */
272 /* not found it yet check if this is the one */
273 /* and this is not the defining one */
274 if (cop->key == cdp->key)
277 /* do a special check this will help in */
278 /* constant propagation & dead code elim */
279 /* for assignments only */
280 if (cdp->diCode->op == '=') {
281 /* if the result is volatile then return result */
282 if (IS_OP_VOLATILE (IC_RESULT (cdp->diCode)))
283 *opp = IC_RESULT (cdp->diCode);
285 /* if this is a straight assignment and
286 left is a temp then prefer the temporary to the
288 if (!POINTER_SET (cdp->diCode) &&
289 IS_ITEMP (IC_RESULT (cdp->diCode)) &&
290 IS_TRUE_SYMOP (IC_RIGHT (cdp->diCode)))
291 *opp = IC_RESULT (cdp->diCode);
293 /* if straight assignement && and both
294 are temps then prefer the one that
295 will not need extra space to spil, also
296 take into consideration if right side
297 an induction variable
299 if (!POINTER_SET (cdp->diCode) &&
300 IS_ITEMP (IC_RESULT (cdp->diCode)) &&
301 IS_ITEMP (IC_RIGHT (cdp->diCode)) &&
302 !OP_SYMBOL (IC_RIGHT (cdp->diCode))->isind &&
303 !OP_SYMBOL(IC_RIGHT (cdp->diCode))->isreqv &&
304 ((!SPIL_LOC (IC_RIGHT (cdp->diCode)) &&
305 SPIL_LOC (IC_RESULT (cdp->diCode))) ||
306 (SPIL_LOC (IC_RESULT (cdp->diCode)) &&
307 SPIL_LOC (IC_RESULT (cdp->diCode)) ==
308 SPIL_LOC (IC_RIGHT (cdp->diCode)))))
309 *opp = IC_RESULT (cdp->diCode);
311 *opp = IC_RIGHT (cdp->diCode);
315 *opp = IC_RESULT (cdp->diCode);
318 /* if this is an assign to a temp. then check
319 if the right side is this then return this */
320 if (IS_TRUE_SYMOP (cop) &&
321 cdp->diCode->op == '=' &&
322 !POINTER_SET (cdp->diCode) &&
323 cop->key == IC_RIGHT (cdp->diCode)->key &&
324 !isGlobalInNearSpace (IC_RIGHT (cdp->diCode)) &&
325 IS_ITEMP (IC_RESULT (cdp->diCode)))
326 *opp = IC_RESULT (cdp->diCode);
329 (isOperandLiteral(*opp) || !checkSign ||
331 IS_SPEC(operandType (cop)) && IS_SPEC(operandType (*opp)) &&
332 (SPEC_USIGN(operandType (cop))==SPEC_USIGN(operandType (*opp)) &&
333 (SPEC_LONG(operandType (cop))==SPEC_LONG(operandType (*opp)))))))
336 if ((isGlobalInNearSpace (cop) &&
337 !isOperandLiteral (*opp)) ||
338 isOperandVolatile (*opp, FALSE)
345 if (cop->key == (*opp)->key)
351 if ((*opp)->isaddr != cop->isaddr && IS_ITEMP (cop))
353 *opp = operandFromOperand (*opp);
354 (*opp)->isaddr = cop->isaddr;
357 if (IS_SPEC(operandType (cop)) && IS_SPEC(operandType (*opp)) &&
358 SPEC_NOUN(operandType(cop)) != SPEC_NOUN(operandType(*opp)))
360 // special case: we can make an unsigned char literal
361 // into an int literal with no cost.
362 if (isOperandLiteral(*opp)
363 && SPEC_NOUN(operandType(*opp)) == V_CHAR
364 && SPEC_NOUN(operandType(cop)) == V_INT)
366 *opp = operandFromOperand (*opp);
367 SPEC_NOUN(operandType(*opp)) = V_INT;
385 /*-----------------------------------------------------------------*/
386 /* findPointerSet - finds the right side of a pointer set op */
387 /*-----------------------------------------------------------------*/
388 DEFSETFUNC (findPointerSet)
391 V_ARG (operand *, op);
392 V_ARG (operand **, opp);
393 V_ARG (operand *, rop);
395 if (POINTER_SET (cdp->diCode) &&
396 IC_RESULT (cdp->diCode)->key == op->key &&
397 !isOperandVolatile (IC_RESULT (cdp->diCode), TRUE) &&
398 !isOperandVolatile (IC_RIGHT (cdp->diCode), TRUE) &&
399 getSize (operandType (IC_RIGHT (cdp->diCode))) ==
400 getSize (operandType (rop)))
402 *opp = IC_RIGHT (cdp->diCode);
409 /*-----------------------------------------------------------------*/
410 /* findPrevIc - cseBBlock support function will return the iCode */
411 /* which matches the current one */
412 /*-----------------------------------------------------------------*/
413 DEFSETFUNC (findPrevIc)
417 V_ARG (iCode **, icp);
419 /* if already found */
423 /* if the iCodes are the same */
424 if (isiCodeEqual (ic, cdp->diCode) &&
425 isOperandEqual (cdp->sym, IC_RESULT (cdp->diCode)))
431 /* if iCodes are not the same */
432 /* see the operands maybe interchanged */
433 if (ic->op == cdp->diCode->op &&
434 (ic->op == '+' || ic->op == '*') &&
435 isOperandEqual (IC_LEFT (ic), IC_RIGHT (cdp->diCode)) &&
436 isOperandEqual (IC_RIGHT (ic), IC_LEFT (cdp->diCode)))
445 /*-------------------------------------------------------------------*/
446 /* ifAssignedFromGlobal - if definition is an assignment from global */
447 /*-------------------------------------------------------------------*/
448 DEFSETFUNC (ifAssignedFromGlobal)
451 iCode *dic=cdp->diCode;
453 if (dic->op=='=' && isOperandGlobal(IC_RIGHT(dic))) {
459 /*-----------------------------------------------------------------*/
460 /* ifDefGlobal - if definition is global */
461 /*-----------------------------------------------------------------*/
462 DEFSETFUNC (ifDefGlobal)
466 return (isOperandGlobal (cdp->sym));
469 /*-----------------------------------------------------------------*/
470 /* ifAnyGetPointer - if get pointer icode */
471 /*-----------------------------------------------------------------*/
472 DEFSETFUNC (ifAnyGetPointer)
476 if (cdp->diCode && POINTER_GET (cdp->diCode))
481 /*-----------------------------------------------------------------*/
482 /* ifOperandsHave - if any of the operand are the same as this */
483 /*-----------------------------------------------------------------*/
484 DEFSETFUNC (ifOperandsHave)
487 V_ARG (operand *, op);
490 if (IC_LEFT (cdp->diCode) &&
491 IS_SYMOP (IC_LEFT (cdp->diCode)) &&
492 IC_LEFT (cdp->diCode)->key == op->key)
495 if (IC_RIGHT (cdp->diCode) &&
496 IS_SYMOP (IC_RIGHT (cdp->diCode)) &&
497 IC_RIGHT (cdp->diCode)->key == op->key)
500 /* or if any of the operands are volatile */
501 if (IC_LEFT (cdp->diCode) &&
502 IS_OP_VOLATILE (IC_LEFT (cdp->diCode)))
505 if (IC_RIGHT (cdp->diCode) &&
506 IS_OP_VOLATILE (IC_RIGHT (cdp->diCode)))
510 if (IC_RESULT (cdp->diCode) &&
511 IS_OP_VOLATILE (IC_RESULT (cdp->diCode)))
517 /*-----------------------------------------------------------------*/
518 /* ifDefSymIs - if a definition is found in the set */
519 /*-----------------------------------------------------------------*/
521 ifDefSymIs (set * cseSet, operand * sym)
526 if (!sym || !IS_SYMOP (sym))
528 for (sl = cseSet; sl; sl = sl->next)
531 if (loop->sym->key == sym->key)
538 /*-----------------------------------------------------------------*/
539 /* ifDefSymIsX - will return 1 if the symbols match */
540 /*-----------------------------------------------------------------*/
541 DEFSETFUNC (ifDefSymIsX)
544 V_ARG (operand *, op);
547 return cdp->sym->key == op->key;
549 return (isOperandEqual (cdp->sym, op));
554 /*-----------------------------------------------------------------*/
555 /* ifDiCodeIs - returns truw if diCode is same */
556 /*-----------------------------------------------------------------*/
558 ifDiCodeIs (set * cseSet, iCode * ic)
566 for (sl = cseSet; sl; sl = sl->next)
569 if (loop->diCode == ic)
576 /*-----------------------------------------------------------------*/
577 /* ifPointerGet - returns true if the icode is pointer get sym */
578 /*-----------------------------------------------------------------*/
579 DEFSETFUNC (ifPointerGet)
582 V_ARG (operand *, op);
583 iCode *dic = cdp->diCode;
584 operand *left = IC_LEFT (cdp->diCode);
586 if (POINTER_GET (dic) && left->key == op->key)
592 /*-----------------------------------------------------------------*/
593 /* ifPointerSet - returns true if the icode is pointer set sym */
594 /*-----------------------------------------------------------------*/
595 DEFSETFUNC (ifPointerSet)
598 V_ARG (operand *, op);
600 if (POINTER_SET (cdp->diCode) &&
601 IC_RESULT (cdp->diCode)->key == op->key)
607 /*-----------------------------------------------------------------*/
608 /* ifDiCodeIsX - will return 1 if the symbols match */
609 /*-----------------------------------------------------------------*/
610 DEFSETFUNC (ifDiCodeIsX)
615 return cdp->diCode == ic;
619 /*-----------------------------------------------------------------*/
620 /* findBackwardDef - scan backwards to find deinition of operand */
621 /*-----------------------------------------------------------------*/
622 iCode *findBackwardDef(operand *op,iCode *ic)
626 for (lic = ic; lic ; lic = lic->prev) {
627 if (IC_RESULT(lic) && isOperandEqual(op,IC_RESULT(lic)))
633 /*-----------------------------------------------------------------*/
634 /* algebraicOpts - does some algebraic optimizations */
635 /*-----------------------------------------------------------------*/
637 algebraicOpts (iCode * ic, eBBlock * ebp)
639 /* we don't deal with the following iCodes
650 /* if both operands present & ! IFX */
651 /* then if they are both literal we */
652 /* perform the operation right now */
653 if (IC_RESULT (ic) &&
656 IS_OP_LITERAL (IC_LEFT (ic)) &&
657 IS_OP_LITERAL (IC_RIGHT (ic)))
660 IC_RIGHT (ic) = operandOperation (IC_LEFT (ic),
663 operandType (IC_RESULT (ic)));
666 SET_RESULT_RIGHT (ic);
670 /* if not ifx & only one operand present */
671 if (IC_RESULT (ic) &&
673 IS_OP_LITERAL (IC_LEFT (ic)) &&
677 IC_RIGHT (ic) = operandOperation (IC_LEFT (ic),
680 operandType (IC_RESULT (ic)));
683 SET_RESULT_RIGHT (ic);
688 /* a special case : or in short a kludgy solution will think
689 about a better solution over a glass of wine someday */
690 if (ic->op == GET_VALUE_AT_ADDRESS)
693 if (IS_ITEMP (IC_RESULT (ic)) &&
694 IS_TRUE_SYMOP (IC_LEFT (ic)))
698 IC_RIGHT (ic) = operandFromOperand (IC_LEFT (ic));
699 IC_RIGHT (ic)->isaddr = 0;
701 IC_RESULT (ic) = operandFromOperand (IC_RESULT (ic));
702 IC_RESULT (ic)->isaddr = 0;
703 setOperandType (IC_RESULT (ic), operandType (IC_RIGHT (ic)));
707 if (IS_ITEMP (IC_LEFT (ic)) &&
708 IS_ITEMP (IC_RESULT (ic)) &&
709 /* !OP_SYMBOL(IC_RESULT(ic))->isreqv && */
710 /* !OP_SYMBOL(IC_LEFT(ic))->isreqv && */
711 !IC_LEFT (ic)->isaddr)
714 IC_RIGHT (ic) = operandFromOperand (IC_LEFT (ic));
715 IC_RIGHT (ic)->isaddr = 0;
716 IC_RESULT (ic) = operandFromOperand (IC_RESULT (ic));
717 IC_RESULT (ic)->isaddr = 0;
725 /* depending on the operation */
729 /* if adding the same thing change to left shift by 1 */
730 if (IC_LEFT (ic)->key == IC_RIGHT (ic)->key &&
731 !IS_FLOAT (operandType (IC_RESULT (ic))))
734 IC_RIGHT (ic) = operandFromLit (1);
737 /* if addition then check if one of them is a zero */
738 /* if yes turn it into assignmnt */
739 if (IS_OP_LITERAL (IC_LEFT (ic)) &&
740 operandLitValue (IC_LEFT (ic)) == 0.0)
745 SET_ISADDR (IC_RESULT (ic), 0);
746 SET_ISADDR (IC_RIGHT (ic), 0);
749 if (IS_OP_LITERAL (IC_RIGHT (ic)) &&
750 operandLitValue (IC_RIGHT (ic)) == 0.0)
754 IC_RIGHT (ic) = IC_LEFT (ic);
756 SET_ISADDR (IC_RIGHT (ic), 0);
757 SET_ISADDR (IC_RESULT (ic), 0);
762 /* if subtracting the the same thing then zero */
763 if (IC_LEFT (ic)->key == IC_RIGHT (ic)->key)
766 IC_RIGHT (ic) = operandFromLit (0);
768 IC_RESULT (ic) = operandFromOperand (IC_RESULT (ic));
769 IC_RESULT (ic)->isaddr = 0;
773 /* if subtraction then check if one of the operand */
774 /* is zero then depending on which operand change */
775 /* to assignment or unary minus */
776 if (IS_OP_LITERAL (IC_RIGHT (ic)) &&
777 operandLitValue (IC_RIGHT (ic)) == 0.0)
779 /* right size zero change to assignment */
781 IC_RIGHT (ic) = IC_LEFT (ic);
783 SET_ISADDR (IC_RIGHT (ic), 0);
784 SET_ISADDR (IC_RESULT (ic), 0);
787 if (IS_OP_LITERAL (IC_LEFT (ic)) &&
788 operandLitValue (IC_LEFT (ic)) == 0.0)
790 /* left zero turn into an unary minus */
792 IC_LEFT (ic) = IC_RIGHT (ic);
793 IC_RIGHT (ic) = NULL;
797 /* if multiplication then check if either of */
798 /* them is zero then the result is zero */
799 /* if either of them is one then result is */
802 if (IS_OP_LITERAL (IC_LEFT (ic)))
805 if (operandLitValue (IC_LEFT (ic)) == 0.0)
808 IC_RIGHT (ic) = IC_LEFT (ic);
810 SET_RESULT_RIGHT (ic);
813 if (operandLitValue (IC_LEFT (ic)) == 1.0)
815 /* '*' can have two unsigned chars as operands */
816 /* and an unsigned int as result. */
817 if (compareType (operandType (IC_RESULT (ic)),
818 operandType (IC_RIGHT (ic))) == 1)
822 SET_RESULT_RIGHT (ic);
827 IC_LEFT (ic)->type = TYPE;
828 IC_LEFT (ic)->isLiteral = 0;
829 setOperandType (IC_LEFT (ic), operandType (IC_RESULT (ic)));
835 if (IS_OP_LITERAL (IC_RIGHT (ic)))
838 if (operandLitValue (IC_RIGHT (ic)) == 0.0)
842 SET_RESULT_RIGHT (ic);
846 if (operandLitValue (IC_RIGHT (ic)) == 1.0)
848 /* '*' can have two unsigned chars as operands */
849 /* and an unsigned int as result. */
850 if (compareType (operandType (IC_RESULT (ic)),
851 operandType (IC_LEFT (ic))) == 1)
854 IC_RIGHT (ic) = IC_LEFT (ic);
856 SET_RESULT_RIGHT (ic);
864 IC_RIGHT (ic) = IC_LEFT (ic);
866 IC_LEFT (ic)->type = TYPE;
867 IC_LEFT (ic)->isLiteral = 0;
868 setOperandType (IC_LEFT (ic), operandType (IC_RESULT (ic)));
875 /* if division by self then 1 */
876 if (IC_LEFT (ic)->key == IC_RIGHT (ic)->key)
879 IC_RIGHT (ic) = operandFromLit (1);
881 IC_RESULT (ic) = operandFromOperand (IC_RESULT (ic));
882 IC_RESULT (ic)->isaddr = 0;
885 /* if this is a division then check if right */
886 /* is one then change it to an assignment */
887 if (IS_OP_LITERAL (IC_RIGHT (ic)) &&
888 operandLitValue (IC_RIGHT (ic)) == 1.0)
892 IC_RIGHT (ic) = IC_LEFT (ic);
894 SET_RESULT_RIGHT (ic);
898 /* if both are the same for an comparison operators */
902 if (isOperandEqual (IC_LEFT (ic), IC_RIGHT (ic)))
905 IC_RIGHT (ic) = operandFromLit (1);
907 SET_RESULT_RIGHT (ic);
913 if (isOperandEqual (IC_LEFT (ic), IC_RIGHT (ic)))
916 IC_RIGHT (ic) = operandFromLit (0);
918 SET_RESULT_RIGHT (ic);
923 sym_link *otype = operandType(IC_RIGHT(ic));
924 sym_link *ctype = operandType(IC_LEFT(ic));
925 /* if this is a cast of a literal value */
926 if (IS_OP_LITERAL (IC_RIGHT (ic)) &&
927 !(IS_GENPTR(ctype) && (IS_PTR(otype) && !IS_GENPTR(otype)))) {
930 operandFromValue (valCastLiteral (operandType (IC_LEFT (ic)),
931 operandLitValue (IC_RIGHT (ic))));
933 SET_ISADDR (IC_RESULT (ic), 0);
935 /* if casting to the same */
936 if (compareType (operandType (IC_RESULT (ic)),
937 operandType (IC_RIGHT (ic))) == 1) {
940 SET_ISADDR (IC_RESULT (ic), 0);
945 if (IS_OP_LITERAL (IC_LEFT (ic)))
949 (operandLitValue (IC_LEFT (ic)) == 0 ?
950 operandFromLit (1) : operandFromLit (0));
952 SET_ISADDR (IC_RESULT (ic), 0);
956 /* if both operands are equal */
957 /* if yes turn it into assignment */
958 if (isOperandEqual (IC_LEFT (ic), IC_RIGHT (ic)))
960 if (IS_OP_VOLATILE (IC_LEFT (ic)))
962 iCode *newic = newiCode (DUMMY_READ_VOLATILE, NULL, IC_LEFT (ic));
963 IC_RESULT (newic) = IC_LEFT (ic);
964 newic->lineno = ic->lineno;
965 addiCodeToeBBlock (ebp, newic, ic->next);
969 SET_RESULT_RIGHT (ic);
972 /* swap literal to right ic */
973 if (IS_OP_LITERAL (IC_LEFT (ic)))
978 IC_LEFT (ic) = IC_RIGHT (ic);
981 if (IS_OP_LITERAL (IC_RIGHT (ic)))
983 /* if BITWISEAND then check if one of them is a zero */
984 /* if yes turn it into 0 assignment */
985 if (operandLitValue (IC_RIGHT (ic)) == 0.0)
987 if (IS_OP_VOLATILE (IC_LEFT (ic)))
989 iCode *newic = newiCode (DUMMY_READ_VOLATILE, NULL, IC_LEFT (ic));
990 IC_RESULT (newic) = IC_LEFT (ic);
991 newic->lineno = ic->lineno;
992 addiCodeToeBBlock (ebp, newic, ic->next);
996 SET_RESULT_RIGHT (ic);
999 /* if BITWISEAND then check if one of them is 0xff... */
1000 /* if yes turn it into assignment */
1004 switch (getSize (operandType (IC_RIGHT (ic))))
1018 if (((unsigned) operandLitValue (IC_RIGHT (ic)) & val) == val)
1021 IC_RIGHT (ic) = IC_LEFT (ic);
1022 IC_LEFT (ic) = NULL;
1023 SET_RESULT_RIGHT (ic);
1030 /* if both operands are equal */
1031 /* if yes turn it into assignment */
1032 if (isOperandEqual (IC_LEFT (ic), IC_RIGHT (ic)))
1034 if (IS_OP_VOLATILE (IC_LEFT (ic)))
1036 iCode *newic = newiCode (DUMMY_READ_VOLATILE, NULL, IC_LEFT (ic));
1037 IC_RESULT (newic) = IC_LEFT (ic);
1038 newic->lineno = ic->lineno;
1039 addiCodeToeBBlock (ebp, newic, ic->next);
1042 IC_LEFT (ic) = NULL;
1043 SET_RESULT_RIGHT (ic);
1046 /* swap literal to right ic */
1047 if (IS_OP_LITERAL (IC_LEFT (ic)))
1052 IC_LEFT (ic) = IC_RIGHT (ic);
1055 if (IS_OP_LITERAL (IC_RIGHT (ic)))
1057 /* if BITWISEOR then check if one of them is a zero */
1058 /* if yes turn it into assignment */
1059 if (operandLitValue (IC_RIGHT (ic)) == 0.0)
1062 IC_RIGHT (ic) = IC_LEFT (ic);
1063 IC_LEFT (ic) = NULL;
1064 SET_RESULT_RIGHT (ic);
1067 /* if BITWISEOR then check if one of them is 0xff... */
1068 /* if yes turn it into 0xff... assignment */
1072 switch (getSize (operandType (IC_RIGHT (ic))))
1086 if (((unsigned) operandLitValue (IC_RIGHT (ic)) & val) == val)
1088 if (IS_OP_VOLATILE (IC_LEFT (ic)))
1090 iCode *newic = newiCode (DUMMY_READ_VOLATILE, NULL, IC_LEFT (ic));
1091 IC_RESULT (newic) = IC_LEFT (ic);
1092 newic->lineno = ic->lineno;
1093 addiCodeToeBBlock (ebp, newic, ic->next);
1096 IC_LEFT (ic) = NULL;
1097 SET_RESULT_RIGHT (ic);
1104 /* if both operands are equal */
1105 /* if yes turn it into 0 assignment */
1106 if (isOperandEqual (IC_LEFT (ic), IC_RIGHT (ic)))
1108 if (IS_OP_VOLATILE (IC_LEFT (ic)))
1110 iCode *newic = newiCode (DUMMY_READ_VOLATILE, NULL, IC_LEFT (ic));
1111 IC_RESULT (newic) = IC_LEFT (ic);
1112 newic->lineno = ic->lineno;
1113 addiCodeToeBBlock (ebp, newic, ic->next);
1115 newic = newiCode (DUMMY_READ_VOLATILE, NULL, IC_LEFT (ic));
1116 IC_RESULT (newic) = IC_LEFT (ic);
1117 newic->lineno = ic->lineno;
1118 addiCodeToeBBlock (ebp, newic, ic->next);
1121 IC_RIGHT (ic) = operandFromLit (0);
1122 IC_LEFT (ic) = NULL;
1123 SET_RESULT_RIGHT (ic);
1126 /* swap literal to right ic */
1127 if (IS_OP_LITERAL (IC_LEFT (ic)))
1132 IC_LEFT (ic) = IC_RIGHT (ic);
1135 /* if XOR then check if one of them is a zero */
1136 /* if yes turn it into assignment */
1137 if (IS_OP_LITERAL (IC_RIGHT (ic)))
1139 if (operandLitValue (IC_RIGHT (ic)) == 0.0)
1142 IC_RIGHT (ic) = IC_LEFT (ic);
1143 IC_LEFT (ic) = NULL;
1144 SET_RESULT_RIGHT (ic);
1153 #define OTHERS_PARM(s) (s->_isparm && !s->ismyparm)
1154 /*-----------------------------------------------------------------*/
1155 /* updateSpillLocation - keeps track of register spill location */
1156 /*-----------------------------------------------------------------*/
1158 updateSpillLocation (iCode * ic, int induction)
1162 if (POINTER_SET (ic))
1168 /* for the form true_symbol := iTempNN */
1169 if (ASSIGN_ITEMP_TO_SYM (ic) &&
1170 !SPIL_LOC (IC_RIGHT (ic))) {
1172 setype = getSpec (operandType (IC_RESULT (ic)));
1174 if (!OP_SYMBOL(IC_RIGHT (ic))->noSpilLoc &&
1175 !IS_VOLATILE (setype) &&
1176 !IN_FARSPACE (SPEC_OCLS (setype)) &&
1177 !OTHERS_PARM (OP_SYMBOL (IC_RESULT (ic))))
1179 wassert(IS_SYMOP(IC_RESULT (ic)));
1180 wassert(IS_SYMOP(IC_RIGHT (ic)));
1181 SPIL_LOC (IC_RIGHT (ic)) =
1182 IC_RESULT (ic)->operand.symOperand;
1187 #if 0 /* this needs furthur investigation can save a lot of code */
1188 if (ASSIGN_SYM_TO_ITEMP(ic) &&
1189 !SPIL_LOC(IC_RESULT(ic))) {
1190 if (!OTHERS_PARM (OP_SYMBOL (IC_RIGHT (ic))))
1191 SPIL_LOC (IC_RESULT (ic)) =
1192 IC_RIGHT (ic)->operand.symOperand;
1195 if (ASSIGN_ITEMP_TO_ITEMP (ic)) {
1197 if (!SPIL_LOC (IC_RIGHT (ic)) &&
1198 !bitVectBitsInCommon (OP_DEFS (IC_RIGHT (ic)), OP_USES (IC_RESULT (ic))) &&
1199 OP_SYMBOL (IC_RESULT (ic))->isreqv) {
1201 setype = getSpec (operandType (IC_RESULT (ic)));
1203 if (!OP_SYMBOL(IC_RIGHT (ic))->noSpilLoc &&
1204 !IS_VOLATILE (setype) &&
1205 !IN_FARSPACE (SPEC_OCLS (setype)) &&
1206 !OTHERS_PARM (OP_SYMBOL (IC_RESULT (ic))))
1208 SPIL_LOC (IC_RIGHT (ic)) =
1209 SPIL_LOC (IC_RESULT (ic));
1211 /* special case for inductions */
1213 OP_SYMBOL(IC_RIGHT(ic))->isreqv &&
1214 !OP_SYMBOL(IC_RESULT (ic))->noSpilLoc &&
1215 !SPIL_LOC(IC_RESULT(ic))) {
1216 SPIL_LOC (IC_RESULT (ic)) = SPIL_LOC (IC_RIGHT (ic));
1220 /*-----------------------------------------------------------------*/
1221 /* setUsesDef - sets the uses def bitvector for a given operand */
1222 /*-----------------------------------------------------------------*/
1224 setUsesDefs (operand * op, bitVect * bdefs,
1225 bitVect * idefs, bitVect ** oud)
1227 /* compute the definitions alive at this point */
1228 bitVect *adefs = bitVectUnion (bdefs, idefs);
1230 /* of these definitions find the ones that are */
1231 /* for this operand */
1232 adefs = bitVectIntersect (adefs, OP_DEFS (op));
1234 /* these are the definitions that this operand can use */
1235 op->usesDefs = adefs;
1237 /* the out defs is an union */
1238 *oud = bitVectUnion (*oud, adefs);
1241 /*-----------------------------------------------------------------*/
1242 /* unsetDefsAndUses - clear this operation for the operands */
1243 /*-----------------------------------------------------------------*/
1245 unsetDefsAndUses (iCode * ic)
1247 if (ic->op == JUMPTABLE)
1250 /* take away this definition from the def chain of the */
1251 /* result & take away from use set of the operands */
1254 /* turn off def set */
1255 if (IS_SYMOP (IC_RESULT (ic)))
1257 if (!POINTER_SET (ic))
1258 bitVectUnSetBit (OP_DEFS (IC_RESULT (ic)), ic->key);
1260 bitVectUnSetBit (OP_USES (IC_RESULT (ic)), ic->key);
1262 /* turn off the useSet for the operands */
1263 if (IS_SYMOP (IC_LEFT (ic)))
1264 bitVectUnSetBit (OP_USES (IC_LEFT (ic)), ic->key);
1266 if (IS_SYMOP (IC_RIGHT (ic)))
1267 bitVectUnSetBit (OP_USES (IC_RIGHT (ic)), ic->key);
1270 /* must be ifx turn off the use */ if (IS_SYMOP (IC_COND (ic)))
1271 bitVectUnSetBit (OP_USES (IC_COND (ic)), ic->key);
1274 /*-----------------------------------------------------------------*/
1275 /* ifxOptimize - changes ifx conditions if it can */
1276 /*-----------------------------------------------------------------*/
1278 ifxOptimize (iCode * ic, set * cseSet,
1280 eBBlock * ebb, int *change,
1281 eBBlock ** ebbs, int count)
1286 /* if the condition can be replaced */
1290 applyToSetFTrue (cseSet, findCheaperOp, IC_COND (ic), &pdop, 0);
1293 ReplaceOpWithCheaperOp(&IC_COND (ic), pdop);
1298 /* if the conditional is a literal then */
1299 if (IS_OP_LITERAL (IC_COND (ic)))
1302 if ((operandLitValue (IC_COND (ic)) != 0.0) && IC_TRUE (ic))
1305 /* change to a goto */
1307 IC_LABEL (ic) = IC_TRUE (ic);
1314 if (!operandLitValue (IC_COND (ic)) && IC_FALSE (ic))
1317 IC_LABEL (ic) = IC_FALSE (ic);
1323 /* then kill this if condition */
1324 remiCodeFromeBBlock (ebb, ic);
1328 /* now we need to recompute the control flow */
1329 /* since the control flow has changed */
1330 /* this is very expensive but it does not happen */
1331 /* too often, if it does happen then the user pays */
1333 computeControlFlow (ebbs, count, 1);
1334 if (!options.lessPedantic) {
1335 werror (W_CONTROL_FLOW, ic->filename, ic->lineno);
1340 /* if there is only one successor and that successor
1341 is the same one we are conditionally going to then
1342 we can remove this conditional statement */
1343 label = (IC_TRUE (ic) ? IC_TRUE (ic) : IC_FALSE (ic));
1344 if (elementsInSet (ebb->succList) == 1 &&
1345 isinSet (ebb->succList, eBBWithEntryLabel (ebbs, label, count)))
1348 remiCodeFromeBBlock (ebb, ic);
1349 computeControlFlow (ebbs, count, 1);
1350 if (!options.lessPedantic) {
1351 werror (W_CONTROL_FLOW, ic->filename, ic->lineno);
1357 /* if it remains an IFX the update the use Set */
1358 OP_USES(IC_COND (ic))=bitVectSetBit (OP_USES (IC_COND (ic)), ic->key);
1359 setUsesDefs (IC_COND (ic), ebb->defSet, ebb->outDefs, &ebb->usesDefs);
1363 /*-----------------------------------------------------------------*/
1364 /* diCodeForSym - finds the definiting instruction for a symbol */
1365 /*-----------------------------------------------------------------*/
1366 DEFSETFUNC (diCodeForSym)
1369 V_ARG (operand *, sym);
1370 V_ARG (iCode **, dic);
1372 /* if already found */
1376 /* if not if this is the defining iCode */
1377 if (sym->key == cdp->key)
1386 /*-----------------------------------------------------------------*/
1387 /* constFold - does some constant folding */
1388 /*-----------------------------------------------------------------*/
1390 constFold (iCode * ic, set * cseSet)
1394 /* this routine will change
1400 /* deal with only + & - */
1401 if (ic->op != '+' &&
1405 /* this check is a hueristic to prevent live ranges
1406 from becoming too long */
1407 if (IS_PTR (operandType (IC_RESULT (ic))))
1410 /* check if operation with a literal */
1411 if (!IS_OP_LITERAL (IC_RIGHT (ic)))
1414 /* check if we can find a definition for the
1416 if (!(applyToSet (cseSet, diCodeForSym, IC_LEFT (ic), &dic)))
1419 /* check that this is also a +/- */
1420 if (dic->op != '+' && dic->op != '-')
1423 /* with a literal */
1424 if (!IS_OP_LITERAL (IC_RIGHT (dic)))
1427 /* find the definition of the left operand
1428 of dic.then check if this defined with a
1429 get_pointer return 0 if the pointer size is
1430 less than 2 (MCS51 specific) */
1431 if (!(applyToSet (cseSet, diCodeForSym, IC_LEFT (dic), &ldic)))
1434 if (POINTER_GET (ldic) && getSize (operandType (IC_LEFT (ldic))) <= 1)
1437 /* it is if the operations are the same */
1438 /* the literal parts need to be added */
1439 IC_LEFT (ic) = operandFromOperand (IC_LEFT (dic));
1440 if (ic->op == dic->op)
1441 IC_RIGHT (ic) = operandFromLit (operandLitValue (IC_RIGHT (ic)) +
1442 operandLitValue (IC_RIGHT (dic)));
1444 IC_RIGHT (ic) = operandFromLit (operandLitValue (IC_RIGHT (ic)) -
1445 operandLitValue (IC_RIGHT (dic)));
1447 if (IS_ITEMP (IC_RESULT (ic)))
1449 SPIL_LOC (IC_RESULT (ic)) = NULL;
1450 OP_SYMBOL(IC_RESULT (ic))->noSpilLoc = 1;
1457 /*-----------------------------------------------------------------*/
1458 /* deleteGetPointers - called when a pointer is passed as parm */
1459 /* will delete from cseSet all get pointers computed from this */
1460 /* pointer. A simple ifOperandsHave is not good enough here */
1461 /*-----------------------------------------------------------------*/
1463 deleteGetPointers (set ** cseSet, set ** pss, operand * op, eBBlock * ebb)
1465 set *compItems = NULL;
1470 if (!*cseSet && !*pss)
1473 /* first find all items computed from this operand .
1474 This done fairly simply go thru the list and find
1475 those that are computed by arthimetic with this
1477 for (cdp = setFirstItem (*cseSet); cdp; cdp = setNextItem (*cseSet))
1479 if (IS_ARITHMETIC_OP (cdp->diCode))
1481 if (isOperandEqual (IC_LEFT (cdp->diCode), op) ||
1482 isOperandEqual (IC_RIGHT (cdp->diCode), op))
1484 /* save it in our list of items */
1485 addSet (&compItems, IC_RESULT (cdp->diCode));
1487 /* also check for those computed from our computed
1488 list . This will take care of situations like
1489 iTemp1 = iTemp0 + 8;
1490 iTemp2 = iTemp1 + 8; */
1491 if (isinSetWith (compItems, (void*)IC_LEFT (cdp->diCode),
1492 (insetwithFunc)isOperandEqual) ||
1493 isinSetWith (compItems, (void*)IC_RIGHT (cdp->diCode),
1494 (insetwithFunc)isOperandEqual))
1496 addSet (&compItems, IC_RESULT (cdp->diCode));
1501 /* now delete all pointer gets with this op */
1502 deleteItemIf (cseSet, ifPointerGet, op);
1503 deleteItemIf (pss, ifPointerSet, op);
1505 /* set the bit vector used by dataFlow computation later */
1506 ebb->ptrsSet = bitVectSetBit (ebb->ptrsSet, op->key);
1507 /* now for the computed items */
1508 for (cop = setFirstItem (compItems); cop; cop = setNextItem (compItems))
1510 ebb->ptrsSet = bitVectSetBit (ebb->ptrsSet, cop->key);
1511 deleteItemIf (cseSet, ifPointerGet, cop);
1512 deleteItemIf (pss, ifPointerSet, cop);
1516 /*-----------------------------------------------------------------*/
1517 /* delGetPointerSucc - delete get pointer from inExprs of succ with */
1518 /* dfnum > supplied */
1519 /*-----------------------------------------------------------------*/
1520 DEFSETFUNC (delGetPointerSucc)
1522 eBBlock *ebp = item;
1523 V_ARG (operand *, op);
1530 if (ebp->dfnum > dfnum)
1532 deleteItemIf (&ebp->inExprs, ifPointerGet, op);
1535 return applyToSet (ebp->succList, delGetPointerSucc, op, dfnum);
1538 /*-----------------------------------------------------------------*/
1539 /* fixUpTypes - KLUGE HACK fixup a lowering problem */
1540 /*-----------------------------------------------------------------*/
1542 fixUpTypes (iCode * ic)
1544 sym_link *t1 = operandType (IC_LEFT (ic)), *t2;
1546 /* if (TARGET_IS_DS390) */
1547 if (options.model == MODEL_FLAT24)
1553 /* for pointer_gets if the types of result & left r the
1554 same then change it type of result to next */
1556 compareType (t2 = operandType (IC_RESULT (ic)), t1) == 1)
1558 setOperandType (IC_RESULT (ic), t2->next);
1562 /*-----------------------------------------------------------------*/
1563 /* isSignedOp - will return 1 if sign is important to operation */
1564 /*-----------------------------------------------------------------*/
1565 static int isSignedOp (iCode *ic)
1586 case GET_VALUE_AT_ADDRESS:
1612 /*-----------------------------------------------------------------*/
1613 /* cseBBlock - common subexpression elimination for basic blocks */
1614 /* this is the hackiest kludgiest routine in the whole */
1615 /* system. also the most important, since almost all */
1616 /* data flow related information is computed by it */
1617 /*-----------------------------------------------------------------*/
1619 cseBBlock (eBBlock * ebb, int computeOnly,
1620 eBBlock ** ebbs, int count)
1626 set *ptrSetSet = NULL;
1628 /* if this block is not reachable */
1632 /* set of common subexpressions */
1633 cseSet = setFromSet (ebb->inExprs);
1635 /* these will be computed by this routine */
1636 setToNull ((void **) &ebb->outDefs);
1637 setToNull ((void **) &ebb->defSet);
1638 setToNull ((void **) &ebb->usesDefs);
1639 setToNull ((void **) &ebb->ptrsSet);
1640 setToNull ((void **) &ebb->addrOf);
1641 setToNull ((void **) &ebb->ldefs);
1643 ebb->outDefs = bitVectCopy (ebb->inDefs);
1644 bitVectDefault = iCodeKey;
1645 ebb->defSet = newBitVect (iCodeKey);
1646 ebb->usesDefs = newBitVect (iCodeKey);
1648 /* for all the instructions in this block do */
1649 for (ic = ebb->sch; ic; ic = ic->next)
1656 ic->eBBlockNum = ebb->bbnum;
1661 /* if this is an assignment from true symbol
1662 to a temp then do pointer post inc/dec optimzation */
1663 if (ic->op == '=' && !POINTER_SET (ic) &&
1664 IS_PTR (operandType (IC_RESULT (ic))))
1666 ptrPostIncDecOpt (ic);
1669 /* clear the def & use chains for the operands involved */
1670 /* in this operation . since it can change due to opts */
1671 unsetDefsAndUses (ic);
1673 if (ic->op == PCALL || ic->op == CALL || ic->op == RECEIVE)
1675 /* add to defSet of the symbol */
1676 OP_DEFS(IC_RESULT (ic))=
1677 bitVectSetBit (OP_DEFS (IC_RESULT (ic)), ic->key);
1678 /* add to the definition set of this block */
1679 ebb->defSet = bitVectSetBit (ebb->defSet, ic->key);
1680 ebb->ldefs = bitVectSetBit (ebb->ldefs, ic->key);
1681 ebb->outDefs = bitVectCplAnd (ebb->outDefs, OP_DEFS (IC_RESULT (ic)));
1682 setUsesDefs (IC_RESULT (ic), ebb->defSet, ebb->outDefs, &ebb->usesDefs);
1683 /* delete global variables from the cseSet
1684 since they can be modified by the function call */
1685 deleteItemIf (&cseSet, ifDefGlobal);
1687 /* and also itemps assigned from globals */
1688 deleteItemIf (&cseSet, ifAssignedFromGlobal);
1690 /* delete all getpointer iCodes from cseSet, this should
1691 be done only for global arrays & pointers but at this
1692 point we don't know if globals, so to be safe do all */
1693 deleteItemIf (&cseSet, ifAnyGetPointer);
1696 /* for pcall & ipush we need to add to the useSet */
1697 if ((ic->op == PCALL ||
1701 IS_SYMOP (IC_LEFT (ic)))
1704 /* check if they can be replaced */
1708 applyToSetFTrue (cseSet, findCheaperOp, IC_LEFT (ic), &pdop, 0);
1710 ReplaceOpWithCheaperOp(&IC_LEFT(ic), pdop);
1712 /* the lookup could have changed it */
1713 if (IS_SYMOP (IC_LEFT (ic)))
1715 OP_USES(IC_LEFT (ic))=
1716 bitVectSetBit (OP_USES (IC_LEFT (ic)), ic->key);
1717 setUsesDefs (IC_LEFT (ic), ebb->defSet,
1718 ebb->outDefs, &ebb->usesDefs);
1722 /* if we a sending a pointer as a parameter
1723 then kill all cse since the pointed to item
1724 might be changed in the function being called */
1725 if ((ic->op == IPUSH || ic->op == SEND) &&
1726 IS_PTR (operandType (IC_LEFT (ic))))
1728 deleteGetPointers (&cseSet, &ptrSetSet, IC_LEFT (ic), ebb);
1729 ebb->ptrsSet = bitVectSetBit (ebb->ptrsSet, IC_LEFT (ic)->key);
1730 for (i = 0; i < count; ebbs[i++]->visited = 0);
1731 applyToSet (ebb->succList, delGetPointerSucc,
1732 IC_LEFT (ic), ebb->dfnum);
1737 /* if jumptable then mark the usage */
1738 if (ic->op == JUMPTABLE)
1740 OP_USES(IC_JTCOND (ic))=
1741 bitVectSetBit (OP_USES (IC_JTCOND (ic)), ic->key);
1742 setUsesDefs (IC_JTCOND (ic), ebb->defSet,
1743 ebb->outDefs, &ebb->usesDefs);
1751 /* do some algebraic optimizations if possible */
1752 algebraicOpts (ic, ebb);
1753 while (constFold (ic, cseSet));
1757 if (POINTER_GET (ic) && !IS_PTR (operandType (IC_LEFT (ic))))
1759 setOperandType (IC_LEFT (ic),
1760 aggrToPtr (operandType (IC_LEFT (ic)), FALSE));
1764 if (POINTER_SET (ic) && !IS_PTR (operandType (IC_RESULT (ic))))
1766 setOperandType (IC_RESULT (ic),
1767 aggrToPtr (operandType (IC_RESULT (ic)), FALSE));
1770 /* if this is a condition statement then */
1771 /* check if the condition can be replaced */
1774 ifxOptimize (ic, cseSet, computeOnly,
1780 /* if the assignment & result is a temp */
1781 /* see if we can replace it */
1782 if (!computeOnly && ic->op == '=')
1785 /* update the spill location for this */
1786 updateSpillLocation (ic,0);
1788 if (POINTER_SET (ic) &&
1789 !(IS_BITFIELD (OP_SYMBOL (IC_RESULT (ic))->etype)))
1792 applyToSetFTrue (cseSet, findCheaperOp, IC_RESULT (ic), &pdop, 0);
1793 if (pdop && !computeOnly &&
1794 IS_ITEMP (pdop) && IS_PTR(operandType(pdop)))
1795 ReplaceOpWithCheaperOp (&IC_RESULT(ic), pdop);
1799 checkSign = isSignedOp(ic);
1801 /* do the operand lookup i.e. for both the */
1802 /* right & left operand : check the cseSet */
1803 /* to see if they have been replaced if yes */
1804 /* then replace them with those from cseSet */
1806 /* and left is a symbol */
1807 if (IS_SYMOP (IC_LEFT (ic)) &&
1808 !computeOnly && ic->op != ADDRESS_OF)
1812 applyToSetFTrue (cseSet, findCheaperOp, IC_LEFT (ic), &pdop, checkSign);
1815 if (POINTER_GET (ic))
1817 if (IS_ITEMP (pdop) || IS_OP_LITERAL (pdop))
1819 /* some non dominating block does POINTER_SET with
1820 this variable .. unsafe to remove any POINTER_GETs */
1821 if (bitVectBitValue(ebb->ndompset,IC_LEFT(ic)->key))
1822 ebb->ptrsSet = bitVectSetBit(ebb->ptrsSet,pdop->key);
1823 ReplaceOpWithCheaperOp(&IC_LEFT(ic), pdop);
1826 /* check if there is a pointer set
1827 for the same pointer visible if yes
1828 then change this into an assignment */
1830 if (applyToSetFTrue (cseSet, findPointerSet, IC_LEFT (ic), &pdop, IC_RESULT (ic)) &&
1831 !bitVectBitValue (ebb->ptrsSet, pdop->key))
1834 IC_LEFT (ic) = NULL;
1835 ReplaceOpWithCheaperOp(&IC_RIGHT(ic), pdop);
1836 SET_ISADDR (IC_RESULT (ic), 0);
1842 ReplaceOpWithCheaperOp(&IC_LEFT(ic), pdop);
1849 if (IS_SYMOP (IC_RIGHT (ic)) && !computeOnly)
1853 applyToSetFTrue (cseSet, findCheaperOp, IC_RIGHT (ic), &pdop, checkSign);
1855 ReplaceOpWithCheaperOp(&IC_RIGHT(ic), pdop);
1860 /* if left or right changed then do algebraic */
1861 if (!computeOnly && change)
1863 algebraicOpts (ic, ebb);
1864 while (constFold (ic, cseSet));
1867 /* if after all this it becomes an assignment to self
1868 then delete it and continue */
1869 if (ASSIGNMENT_TO_SELF (ic))
1871 remiCodeFromeBBlock (ebb, ic);
1875 /* now we will check to see if the entire */
1876 /* operation has been performed before */
1877 /* and is available */
1878 /* don't do assignments they will be killed */
1879 /* by dead code elimination if required do */
1880 /* it only if result is a temporary */
1882 if (!(POINTER_GET (ic) &&
1883 (IS_BITFIELD (OP_SYMBOL (IC_RESULT (ic))->etype) ||
1884 isOperandVolatile (IC_LEFT (ic), TRUE) ||
1885 bitVectBitValue (ebb->ndompset, IC_LEFT (ic)->key))) &&
1887 IS_ITEMP (IC_RESULT (ic)) &&
1890 applyToSet (cseSet, findPrevIc, ic, &pdic);
1891 if (pdic && compareType (operandType (IC_RESULT (pdic)),
1892 operandType (IC_RESULT (ic))) != 1)
1894 if (pdic && port->cseOk && (*port->cseOk)(ic,pdic) == 0)
1898 /* Alternate code */
1899 if (pdic && IS_ITEMP(IC_RESULT(ic))) {
1900 if (POINTER_GET(ic) && bitVectBitValue(ebb->ptrsSet,IC_LEFT(ic)->key)) {
1901 /* Mmm, found an equivalent pointer get at a lower level.
1902 This could be a loop however with the same pointer set
1905 /* if previous definition found change this to an assignment */
1908 IC_RIGHT(ic) = operandFromOperand(IC_RESULT(pdic));
1909 SET_ISADDR(IC_RESULT(ic),0);
1910 SET_ISADDR(IC_RIGHT (ic),0);
1914 if (!(POINTER_SET (ic)) && IC_RESULT (ic)) {
1915 deleteItemIf (&cseSet, ifDefSymIsX, IC_RESULT (ic));
1916 addSetHead (&cseSet, newCseDef (IC_RESULT (ic), ic));
1920 /* if assignment to a parameter which is not
1921 mine and type is a pointer then delete
1922 pointerGets to take care of aliasing */
1923 if (ASSIGNMENT (ic) &&
1924 OTHERS_PARM (OP_SYMBOL (IC_RESULT (ic))) &&
1925 IS_PTR (operandType (IC_RESULT (ic))))
1927 deleteGetPointers (&cseSet, &ptrSetSet, IC_RIGHT (ic), ebb);
1928 for (i = 0; i < count; ebbs[i++]->visited = 0);
1929 applyToSet (ebb->succList, delGetPointerSucc, IC_RIGHT (ic), ebb->dfnum);
1930 ebb->ptrsSet = bitVectSetBit (ebb->ptrsSet, IC_RIGHT (ic)->key);
1933 /* if this is a pointerget then see if we can replace
1934 this with a previously assigned pointer value */
1935 if (POINTER_GET (ic) &&
1936 !(IS_BITFIELD (OP_SYMBOL (IC_RESULT (ic))->etype) ||
1937 isOperandVolatile (IC_LEFT (ic), TRUE)))
1940 applyToSet (ptrSetSet, findPointerSet, IC_LEFT (ic), &pdop, IC_RESULT (ic));
1941 /* if we find it then locally replace all
1942 references to the result with what we assigned */
1945 replaceAllSymBySym (ic->next, IC_RESULT (ic), pdop, &ebb->ndompset);
1949 /* delete from the cseSet anything that has */
1950 /* operands matching the result of this */
1951 /* except in case of pointer access */
1952 if (!(POINTER_SET (ic)) && IC_RESULT (ic))
1954 deleteItemIf (&cseSet, ifOperandsHave, IC_RESULT (ic));
1955 /* delete any previous definitions */
1956 ebb->defSet = bitVectCplAnd (ebb->defSet, OP_DEFS (IC_RESULT (ic)));
1960 /* add the left & right to the defUse set */
1961 if (IC_LEFT (ic) && IS_SYMOP (IC_LEFT (ic)))
1963 OP_USES(IC_LEFT (ic))=
1964 bitVectSetBit (OP_USES (IC_LEFT (ic)), ic->key);
1965 setUsesDefs (IC_LEFT (ic), ebb->defSet, ebb->outDefs, &ebb->usesDefs);
1969 if (IC_RIGHT (ic) && IS_SYMOP (IC_RIGHT (ic)))
1971 OP_USES(IC_RIGHT (ic))=
1972 bitVectSetBit (OP_USES (IC_RIGHT (ic)), ic->key);
1973 setUsesDefs (IC_RIGHT (ic), ebb->defSet, ebb->outDefs, &ebb->usesDefs);
1977 /* for the result it is special case, put the result */
1978 /* in the defuseSet if it a pointer or array access */
1979 if (POINTER_SET (defic))
1981 OP_USES(IC_RESULT (ic))=
1982 bitVectSetBit (OP_USES (IC_RESULT (ic)), ic->key);
1983 setUsesDefs (IC_RESULT (ic), ebb->defSet, ebb->outDefs, &ebb->usesDefs);
1984 deleteItemIf (&cseSet, ifPointerGet, IC_RESULT (ic));
1985 ebb->ptrsSet = bitVectSetBit (ebb->ptrsSet, IC_RESULT (ic)->key);
1986 /* delete from inexpressions of all successors which
1987 have dfNum > than this block */
1988 for (i = 0; i < count; ebbs[i++]->visited = 0);
1989 applyToSet (ebb->succList, delGetPointerSucc, IC_RESULT (ic), ebb->dfnum);
1991 /* delete from cseSet all other pointer sets
1993 deleteItemIf (&ptrSetSet, ifPointerSet, IC_RESULT (ic));
1994 /* add to the local pointerset set */
1995 addSetHead (&ptrSetSet, newCseDef (IC_RESULT (ic), ic));
1998 /* add the result to defintion set */ if (IC_RESULT (ic))
2000 OP_DEFS(IC_RESULT (ic))=
2001 bitVectSetBit (OP_DEFS (IC_RESULT (ic)), ic->key);
2002 ebb->defSet = bitVectSetBit (ebb->defSet, ic->key);
2003 ebb->outDefs = bitVectCplAnd (ebb->outDefs, OP_DEFS (IC_RESULT (ic)));
2004 ebb->ldefs = bitVectSetBit (ebb->ldefs, ic->key);
2008 /* if this is an addressof instruction then */
2009 /* put the symbol in the address of list & */
2010 /* delete it from the cseSet */
2011 if (defic->op == ADDRESS_OF)
2013 addSetHead (&ebb->addrOf, IC_LEFT (ic));
2014 deleteItemIf (&cseSet, ifDefSymIsX, IC_LEFT (ic));
2018 setToNull ((void **) &ebb->outExprs);
2019 ebb->outExprs = cseSet;
2020 ebb->outDefs = bitVectUnion (ebb->outDefs, ebb->defSet);
2021 ebb->ptrsSet = bitVectUnion (ebb->ptrsSet, ebb->inPtrsSet);
2025 /*-----------------------------------------------------------------*/
2026 /* cseAllBlocks - will sequentially go thru & do cse for all blocks */
2027 /*-----------------------------------------------------------------*/
2029 cseAllBlocks (eBBlock ** ebbs, int count, int computeOnly)
2034 /* if optimization turned off */
2036 for (i = 0; i < count; i++)
2037 change += cseBBlock (ebbs[i], computeOnly, ebbs, count);