if (!IS_SYMOP(op))
return NULL;
- /* only upto 2 bytes since we cannot predict
- the usage of b, & acc */
- if (getSize(operandType(op)) > fAVRReturnSize &&
- ic->op != RETURN &&
- ic->op != SEND)
- return NULL;
+ /* returns only */
+ if (ic->op != RETURN) return NULL;
/* this routine will mark the a symbol as used in one
instruction use only && if the defintion is local
return FALSE ;
}
-/*-----------------------------------------------------------------*/
-/* packRegsForAccUse - pack registers for acc use */
-/*-----------------------------------------------------------------*/
-static void packRegsForAccUse (iCode *ic)
-{
- iCode *uic;
-
- /* if + or - then it has to be one byte result */
- if ((ic->op == '+' || ic->op == '-')
- && getSize(operandType(IC_RESULT(ic))) > 1)
- return ;
-
- /* if shift operation make sure right side is not a literal */
- if (ic->op == RIGHT_OP &&
- ( isOperandLiteral(IC_RIGHT(ic)) ||
- getSize(operandType(IC_RESULT(ic))) > 1))
- return ;
-
- if (ic->op == LEFT_OP &&
- ( isOperandLiteral(IC_RIGHT(ic)) ||
- getSize(operandType(IC_RESULT(ic))) > 1))
- return ;
-
- if (IS_BITWISE_OP(ic) &&
- getSize(operandType(IC_RESULT(ic))) > 1)
- return ;
-
-
- /* has only one definition */
- if (bitVectnBitsOn(OP_DEFS(IC_RESULT(ic))) > 1)
- return ;
-
- /* has only one use */
- if (bitVectnBitsOn(OP_USES(IC_RESULT(ic))) > 1)
- return ;
-
- /* and the usage immediately follows this iCode */
- if (!(uic = hTabItemWithKey(iCodehTab,
- bitVectFirstBit(OP_USES(IC_RESULT(ic))))))
- return ;
-
- if (ic->next != uic)
- return ;
-
- /* if it is a conditional branch then we definitely can */
- if (uic->op == IFX )
- goto accuse;
-
- if ( uic->op == JUMPTABLE )
- return ;
-
- /* if the usage is not is an assignment
- or an arithmetic / bitwise / shift operation then not */
- if (POINTER_SET(uic) &&
- getSize(aggrToPtr(operandType(IC_RESULT(uic)),FALSE)) > 1)
- return;
-
- if (uic->op != '=' &&
- !IS_ARITHMETIC_OP(uic) &&
- !IS_BITWISE_OP(uic) &&
- uic->op != LEFT_OP &&
- uic->op != RIGHT_OP )
- return;
-
- /* if used in ^ operation then make sure right is not a
- literl */
- if (uic->op == '^' && isOperandLiteral(IC_RIGHT(uic)))
- return ;
-
- /* if shift operation make sure right side is not a literal */
- if (uic->op == RIGHT_OP &&
- ( isOperandLiteral(IC_RIGHT(uic)) ||
- getSize(operandType(IC_RESULT(uic))) > 1))
- return ;
-
- if (uic->op == LEFT_OP &&
- ( isOperandLiteral(IC_RIGHT(uic)) ||
- getSize(operandType(IC_RESULT(uic))) > 1))
- return ;
-
- /* make sure that the result of this icode is not on the
- stack, since acc is used to compute stack offset */
- if (IS_TRUE_SYMOP(IC_RESULT(uic)) &&
- OP_SYMBOL(IC_RESULT(uic))->onStack)
- return ;
-
- /* if either one of them in far space then we cannot */
- if ((IS_TRUE_SYMOP(IC_LEFT(uic)) &&
- isOperandInFarSpace(IC_LEFT(uic))) ||
- (IS_TRUE_SYMOP(IC_RIGHT(uic)) &&
- isOperandInFarSpace(IC_RIGHT(uic))))
- return ;
-
- /* if the usage has only one operand then we can */
- if (IC_LEFT(uic) == NULL ||
- IC_RIGHT(uic) == NULL)
- goto accuse;
-
- /* make sure this is on the left side if not
- a '+' since '+' is commutative */
- if (ic->op != '+' &&
- IC_LEFT(uic)->key != IC_RESULT(ic)->key)
- return;
-
- /* if one of them is a literal then we can */
- if ((IC_LEFT(uic) && IS_OP_LITERAL(IC_LEFT(uic))) ||
- (IC_RIGHT(uic) && IS_OP_LITERAL(IC_RIGHT(uic)))) {
- OP_SYMBOL(IC_RESULT(ic))->accuse = 1;
- return ;
- }
-
- /* if the other one is not on stack then we can */
- if (IC_LEFT(uic)->key == IC_RESULT(ic)->key &&
- (IS_ITEMP(IC_RIGHT(uic)) ||
- (IS_TRUE_SYMOP(IC_RIGHT(uic)) &&
- !OP_SYMBOL(IC_RIGHT(uic))->onStack)))
- goto accuse;
-
- if (IC_RIGHT(uic)->key == IC_RESULT(ic)->key &&
- (IS_ITEMP(IC_LEFT(uic)) ||
- (IS_TRUE_SYMOP(IC_LEFT(uic)) &&
- !OP_SYMBOL(IC_LEFT(uic))->onStack)))
- goto accuse ;
-
- return ;
-
- accuse:
- OP_SYMBOL(IC_RESULT(ic))->accuse = 1;
-
-
-}
-
/*-----------------------------------------------------------------*/
/* packForPush - hueristics to reduce iCode for pushing */
/*-----------------------------------------------------------------*/
continue ;
}
- /* reduce for support function calls */
-/* if (ic->supportRtn || ic->op == '+' || ic->op == '-' ) */
-/* packRegsForSupport (ic,ebp); */
-
/* some cases the redundant moves can
can be eliminated for return statements */
if ((ic->op == RETURN || ic->op == SEND))
packRegsForOneuse (ic,IC_LEFT(ic),ebp);
- /* if pointer set & left has a size more than
- one and right is not in far space */
-/* if (POINTER_SET(ic) && */
-/* !isOperandInFarSpace(IC_RIGHT(ic)) && */
-/* !OP_SYMBOL(IC_RESULT(ic))->remat && */
-/* !IS_OP_RUONLY(IC_RIGHT(ic)) && */
-/* getSize(aggrToPtr(operandType(IC_RESULT(ic)),FALSE)) > 1 ) */
-
-/* packRegsForOneuse (ic,IC_RESULT(ic),ebp); */
-
- /* if pointer get */
-/* if (POINTER_GET(ic) && */
-/* !isOperandInFarSpace(IC_RESULT(ic))&& */
-/* !OP_SYMBOL(IC_LEFT(ic))->remat && */
-/* !IS_OP_RUONLY(IC_RESULT(ic)) && */
-/* getSize(aggrToPtr(operandType(IC_LEFT(ic)),FALSE)) > 1 ) */
-
-/* packRegsForOneuse (ic,IC_LEFT(ic),ebp); */
-
-
/* if this is cast for intergral promotion then
check if only use of the definition of the
operand being casted/ if yes then replace
}
}
}
-
- /* pack for PUSH
- iTempNN := (some variable in farspace) V1
- push iTempNN ;
- -------------
- push V1
- */
-/* if (ic->op == IPUSH ) { */
-/* packForPush(ic,ebp); */
-/* } */
-
-
- /* pack registers for accumulator use, when the
- result of an arithmetic or bit wise operation
- has only one use, that use is immediately following
- the defintion and the using iCode has only one
- operand or has two operands but one is literal &
- the result of that operation is not on stack then
- we can leave the result of this operation in acc:b
- combination */
-/* if ((IS_ARITHMETIC_OP(ic) */
-
-/* || IS_BITWISE_OP(ic) */
-
-/* || ic->op == LEFT_OP || ic->op == RIGHT_OP */
-
-/* ) && */
-/* IS_ITEMP(IC_RESULT(ic)) && */
-/* getSize(operandType(IC_RESULT(ic))) <= 2) */
-
-/* packRegsForAccUse (ic); */
-
}
}
projects / fw / sdcc / blobdiff