X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=src%2FSDCCcse.c;h=a5ea44f393830ed470c338d37be4d7b054051f5a;hb=67004551c261d35b69228d8d356e1d277b71c071;hp=54a3ca2a8d4b738bf9670fd1a605ce4ab8f3fd7b;hpb=e96570071ab824f873c84ac0fcefc5a7687d037f;p=fw%2Fsdcc diff --git a/src/SDCCcse.c b/src/SDCCcse.c index 54a3ca2a..a5ea44f3 100644 --- a/src/SDCCcse.c +++ b/src/SDCCcse.c @@ -240,6 +240,7 @@ DEFSETFUNC (findCheaperOp) cseDef *cdp = item; V_ARG (operand *, cop); V_ARG (operand **, opp); + V_ARG (int, checkSign); /* if we have already found it */ if (*opp) @@ -276,6 +277,7 @@ DEFSETFUNC (findCheaperOp) IS_ITEMP (IC_RESULT (cdp->diCode)) && IS_ITEMP (IC_RIGHT (cdp->diCode)) && !OP_SYMBOL (IC_RIGHT (cdp->diCode))->isind && + !OP_SYMBOL(IC_RIGHT (cdp->diCode))->isreqv && ((!SPIL_LOC (IC_RIGHT (cdp->diCode)) && SPIL_LOC (IC_RESULT (cdp->diCode))) || (SPIL_LOC (IC_RESULT (cdp->diCode)) && @@ -301,9 +303,11 @@ DEFSETFUNC (findCheaperOp) *opp = IC_RESULT (cdp->diCode); if ((*opp) && - (SPEC_USIGN(operandType (cop))==SPEC_USIGN(operandType (*opp))) && - (SPEC_LONG(operandType (cop))==SPEC_LONG(operandType (*opp)))) - { + (isOperandLiteral(*opp) || !checkSign || + (checkSign && + (SPEC_USIGN(operandType (cop))==SPEC_USIGN(operandType (*opp)) && + (SPEC_LONG(operandType (cop))==SPEC_LONG(operandType (*opp))))))) + { if ((isGlobalInNearSpace (cop) && !isOperandLiteral (*opp)) || @@ -375,7 +379,7 @@ DEFSETFUNC (findPrevIc) if (isiCodeEqual (ic, cdp->diCode) && isOperandEqual (cdp->sym, IC_RESULT (cdp->diCode))) { - *icp = cdp->diCode; + *icp = cdp->diCode; return 1; } @@ -393,6 +397,20 @@ DEFSETFUNC (findPrevIc) return 0; } +/*-------------------------------------------------------------------*/ +/* ifAssignedFromGlobal - if definition is an assignment from global */ +/*-------------------------------------------------------------------*/ +DEFSETFUNC (ifAssignedFromGlobal) +{ + cseDef *cdp = item; + iCode *dic=cdp->diCode; + + if (dic->op=='=' && isOperandGlobal(IC_RIGHT(dic))) { + return 1; + } + return 0; +} + /*-----------------------------------------------------------------*/ /* ifDefGlobal - if definition is global */ /*-----------------------------------------------------------------*/ @@ -553,6 +571,20 @@ DEFSETFUNC (ifDiCodeIsX) } +/*-----------------------------------------------------------------*/ +/* findBackwardDef - scan backwards to find deinition of operand */ +/*-----------------------------------------------------------------*/ +iCode *findBackwardDef(operand *op,iCode *ic) +{ + iCode *lic; + + for (lic = ic; lic ; lic = lic->prev) { + if (IC_RESULT(lic) && isOperandEqual(op,IC_RESULT(lic))) + return lic; + } + return NULL; +} + /*-----------------------------------------------------------------*/ /* algebraicOpts - does some algebraic optimizations */ /*-----------------------------------------------------------------*/ @@ -772,6 +804,7 @@ algebraicOpts (iCode * ic) IC_LEFT (ic) = NULL; IC_RESULT (ic) = operandFromOperand (IC_RESULT (ic)); IC_RESULT (ic)->isaddr = 0; + break; } /* if this is a division then check if right */ /* is one then change it to an assignment */ @@ -877,6 +910,14 @@ updateSpillLocation (iCode * ic, int induction) IC_RESULT (ic)->operand.symOperand; } +#if 0 /* this needs furthur investigation can save a lot of code */ + if (ASSIGN_SYM_TO_ITEMP(ic) && + !SPIL_LOC(IC_RESULT(ic))) { + if (!OTHERS_PARM (OP_SYMBOL (IC_RIGHT (ic)))) + SPIL_LOC (IC_RESULT (ic)) = + IC_RIGHT (ic)->operand.symOperand; + } +#endif if (ASSIGN_ITEMP_TO_ITEMP (ic)) { if (!SPIL_LOC (IC_RIGHT (ic)) && @@ -972,7 +1013,7 @@ ifxOptimize (iCode * ic, set * cseSet, if (!computeOnly) { pdop = NULL; - applyToSetFTrue (cseSet, findCheaperOp, IC_COND (ic), &pdop); + applyToSetFTrue (cseSet, findCheaperOp, IC_COND (ic), &pdop, 0); if (pdop) { IC_COND (ic) = pdop; @@ -1090,7 +1131,7 @@ constFold (iCode * ic, set * cseSet) /* this check is a hueristic to prevent live ranges from becoming too long */ if (IS_PTR (operandType (IC_RESULT (ic)))) - return 0; + return 0; /* check if operation with a literal */ if (!IS_OP_LITERAL (IC_RIGHT (ic))) @@ -1244,6 +1285,55 @@ fixUpTypes (iCode * ic) } } +/*-----------------------------------------------------------------*/ +/* isSignedOp - will return 1 if sign is important to operation */ +/*-----------------------------------------------------------------*/ +static int isSignedOp (iCode *ic) +{ + switch (ic->op) { + case '!': + case '~': + case UNARYMINUS: + case IPUSH: + case IPOP: + case CALL: + case PCALL: + case RETURN: + case '+': + case '-': + case EQ_OP: + case AND_OP: + case OR_OP: + case '^': + case '|': + case BITWISEAND: + case INLINEASM: + case LEFT_OP: + case GET_VALUE_AT_ADDRESS: + case '=': + case IFX: + case RECEIVE: + case SEND: + return 0; + case '*': + case '/': + case '%': + case '>': + case '<': + case LE_OP: + case GE_OP: + case NE_OP: + case RRC: + case RLC: + case GETHBIT: + case RIGHT_OP: + case CAST: + case ARRAYINIT: + return 1; + default: + return 0; + } + } /*-----------------------------------------------------------------*/ /* cseBBlock - common subexpression elimination for basic blocks */ /* this is the hackiest kludgiest routine in the whole */ @@ -1287,6 +1377,9 @@ cseBBlock (eBBlock * ebb, int computeOnly, iCode *pdic; operand *pdop; iCode *defic; + int checkSign ; + + ic->eBBlockNum = ebb->bbnum; if (SKIP_IC2 (ic)) continue; @@ -1316,6 +1409,10 @@ cseBBlock (eBBlock * ebb, int computeOnly, /* delete global variables from the cseSet since they can be modified by the function call */ deleteItemIf (&cseSet, ifDefGlobal); + + /* and also itemps assigned from globals */ + deleteItemIf (&cseSet, ifAssignedFromGlobal); + /* delete all getpointer iCodes from cseSet, this should be done only for global arrays & pointers but at this point we don't know if globals, so to be safe do all */ @@ -1334,7 +1431,7 @@ cseBBlock (eBBlock * ebb, int computeOnly, if (!computeOnly) { pdop = NULL; - applyToSetFTrue (cseSet, findCheaperOp, IC_LEFT (ic), &pdop); + applyToSetFTrue (cseSet, findCheaperOp, IC_LEFT (ic), &pdop, 0); if (pdop) IC_LEFT (ic) = pdop; } @@ -1416,12 +1513,14 @@ cseBBlock (eBBlock * ebb, int computeOnly, !(IS_BITFIELD (OP_SYMBOL (IC_RESULT (ic))->etype))) { pdop = NULL; - applyToSetFTrue (cseSet, findCheaperOp, IC_RESULT (ic), &pdop); + applyToSetFTrue (cseSet, findCheaperOp, IC_RESULT (ic), &pdop, 0); if (pdop && IS_ITEMP (pdop) && !computeOnly) IC_RESULT (ic) = pdop; } } + checkSign = isSignedOp(ic); + /* do the operand lookup i.e. for both the */ /* right & left operand : check the cseSet */ /* to see if they have been replaced if yes */ @@ -1433,13 +1532,17 @@ cseBBlock (eBBlock * ebb, int computeOnly, { pdop = NULL; - applyToSetFTrue (cseSet, findCheaperOp, IC_LEFT (ic), &pdop); + applyToSetFTrue (cseSet, findCheaperOp, IC_LEFT (ic), &pdop, checkSign); if (pdop) { if (POINTER_GET (ic)) { if (IS_ITEMP (pdop) || IS_OP_LITERAL (pdop)) { + /* some non dominating block does POINTER_SET with + this variable .. unsafe to remove any POINTER_GETs */ + if (bitVectBitValue(ebb->ndompset,IC_LEFT(ic)->key)) + ebb->ptrsSet = bitVectSetBit(ebb->ptrsSet,pdop->key); IC_LEFT (ic) = pdop; change = 1; } @@ -1470,10 +1573,9 @@ cseBBlock (eBBlock * ebb, int computeOnly, { pdop = NULL; - applyToSetFTrue (cseSet, findCheaperOp, IC_RIGHT (ic), &pdop); + applyToSetFTrue (cseSet, findCheaperOp, IC_RIGHT (ic), &pdop, checkSign); if (pdop) { - IC_RIGHT (ic) = pdop; change = 1; } @@ -1509,78 +1611,28 @@ cseBBlock (eBBlock * ebb, int computeOnly, IS_ITEMP (IC_RESULT (ic)) && !computeOnly) { - applyToSet (cseSet, findPrevIc, ic, &pdic); + applyToSet (cseSet, findPrevIc, ic, &pdic); if (pdic && compareType (operandType (IC_RESULT (pdic)), operandType (IC_RESULT (ic))) != 1) pdic = NULL; + if (pdic && port->cseOk && (*port->cseOk)(ic,pdic) == 0) + pdic = NULL; } -#if 0 - /* if found then eliminate this and add to */ - /* to cseSet an element containing result */ - /* of this with previous opcode */ - if (pdic) - { - if (IS_ITEMP (IC_RESULT (ic))) - { - - /* replace in the remaining of this block */ - replaceAllSymBySym (ic->next, IC_RESULT (ic), IC_RESULT (pdic), &ebb->ndompset); - /* remove this iCode from inexpressions of all - its successors, it cannot be in the in expressions - of any of the predecessors */ - for (i = 0; i < count; ebbs[i++]->visited = 0); - applyToSet (ebb->succList, removeFromInExprs, ic, IC_RESULT (ic), - IC_RESULT (pdic), ebb); - - /* if this was moved from another block */ - /* then replace in those blocks too */ - if (ic->movedFrom) - { - eBBlock *owner; - for (owner = setFirstItem (ic->movedFrom); owner; - owner = setNextItem (ic->movedFrom)) - replaceAllSymBySym (owner->sch, IC_RESULT (ic), IC_RESULT (pdic), &owner->ndompset); - } - pdic->movedFrom = unionSets (pdic->movedFrom, ic->movedFrom, THROW_NONE); - } - else - addSetHead (&cseSet, newCseDef (IC_RESULT (ic), pdic)); - - if (!computeOnly) - /* eliminate this */ - remiCodeFromeBBlock (ebb, ic); - - defic = pdic; - change++; - - if (IS_ITEMP (IC_RESULT (ic))) - continue; - - } - else - { - - /* just add this as a previous expression except in */ - /* case of a pointer access in which case this is a */ - /* usage not a definition */ - if (!(POINTER_SET (ic)) && IC_RESULT (ic)) - { - deleteItemIf (&cseSet, ifDefSymIsX, IC_RESULT (ic)); - addSetHead (&cseSet, newCseDef (IC_RESULT (ic), ic)); - } - defic = ic; - - } -#else /* Alternate code */ if (pdic && IS_ITEMP(IC_RESULT(ic))) { + if (POINTER_GET(ic) && bitVectBitValue(ebb->ptrsSet,IC_LEFT(ic)->key)) { + /* Mmm, found an equivalent pointer get at a lower level. + This could be a loop however with the same pointer set + later on */ + } else { /* if previous definition found change this to an assignment */ ic->op = '='; IC_LEFT(ic) = NULL; IC_RIGHT(ic) = operandFromOperand(IC_RESULT(pdic)); SET_ISADDR(IC_RESULT(ic),0); SET_ISADDR(IC_RIGHT (ic),0); + } } if (!(POINTER_SET (ic)) && IC_RESULT (ic)) { @@ -1588,7 +1640,7 @@ cseBBlock (eBBlock * ebb, int computeOnly, addSetHead (&cseSet, newCseDef (IC_RESULT (ic), ic)); } defic = ic; -#endif + /* if assignment to a parameter which is not mine and type is a pointer then delete pointerGets to take care of aliasing */