FromData fromDataForArray(AstNode* nodep, AstNode* basefromp, bool rangedSelect) {
// What is the data type and information for this SEL-ish's from()?
UINFO(9," fromData start ddtypep = "<<basefromp<<endl);
VNumRange fromRange; // constructs to isRanged(false)
while (basefromp) {
if (basefromp->castAttrOf()) {
basefromp = basefromp->castAttrOf()->fromp();
continue;
}
break;
}
if (!basefromp || !basefromp->dtypep()) nodep->v3fatalSrc("Select with no from dtype");
AstNodeDType* ddtypep = basefromp->dtypep()->skipRefp();
AstNode* errp = ddtypep;
UINFO(9," fromData.ddtypep = "<<ddtypep<<endl);
if (AstNodeArrayDType* adtypep = ddtypep->castNodeArrayDType()) {
fromRange = adtypep->declRange();
}
else if (AstNodeClassDType* adtypep = ddtypep->castNodeClassDType()) {
fromRange = adtypep->declRange();
}
else if (AstBasicDType* adtypep = ddtypep->castBasicDType()) {
if (adtypep->isRanged()) {
if (adtypep->rangep()
&& (!adtypep->rangep()->msbp()->castConst()
|| !adtypep->rangep()->lsbp()->castConst()))
nodep->v3fatalSrc("Non-constant variable range; errored earlier"); // in constifyParam(bfdtypep)
fromRange = adtypep->declRange();
} else {
nodep->v3error("Illegal bit or array select; type does not have a bit range, or bad dimension: type is "
<<errp->prettyName());
}
}
else {
nodep->v3error("Illegal bit or array select; type already selected, or bad dimension: type is "
<<errp->prettyName());
}
return FromData(errp,ddtypep,fromRange);
}
virtual void visit(AstArraySel* nodep) {
nodep->iterateChildren(*this);
if (!nodep->user1SetOnce()) {
if (debug()==9) nodep->dumpTree(cout,"-in: ");
// Guard against reading/writing past end of arrays
AstNode* basefromp = AstArraySel::baseFromp(nodep->fromp());
bool lvalue = false;
if (AstNodeVarRef* varrefp = basefromp->castNodeVarRef()) {
lvalue = varrefp->lvalue();
} else if (basefromp->castConst()) {
// If it's a PARAMETER[bit], then basefromp may be a constant instead of a varrefp
} else {
nodep->v3fatalSrc("No VarRef or Const under ArraySel");
}
// Find range of dtype we are selecting from
int declElements = -1;
AstNodeDType* dtypep = nodep->fromp()->dtypep()->skipRefp();
if (!dtypep) nodep->v3fatalSrc("Select of non-selectable type");
if (AstNodeArrayDType* adtypep = dtypep->castNodeArrayDType()) {
declElements = adtypep->elementsConst();
} else {
nodep->v3error("Select from non-array "<<dtypep->prettyTypeName());
}
if (debug()>=9) nodep->dumpTree(cout,"arraysel_old: ");
V3Number widthnum (nodep->fileline(), nodep->bitp()->width(), declElements-1);
// See if the condition is constant true
AstNode* condp = new AstGte (nodep->fileline(),
new AstConst(nodep->fileline(), widthnum),
nodep->bitp()->cloneTree(false));
// Note below has null backp(); the Edit function knows how to deal with that.
condp = V3Const::constifyEdit(condp);
if (condp->isOne()) {
// We don't need to add a conditional; we know the existing expression is ok
condp->deleteTree();
}
else if (!lvalue
&& !nodep->backp()->castArraySel()) { // Too complicated and slow if mid-multidimension
// ARRAYSEL(...) -> COND(LT(bit<maxbit), ARRAYSEL(...), {width{1'bx}})
AstNRelinker replaceHandle;
nodep->unlinkFrBack(&replaceHandle);
V3Number xnum (nodep->fileline(), nodep->width());
if (nodep->isString()) {
xnum = V3Number(V3Number::String(), nodep->fileline(), "");
} else {
xnum.setAllBitsX();
}
AstNode* newp = new AstCondBound (nodep->fileline(),
condp,
nodep,
new AstConst(nodep->fileline(), xnum));
if (debug()>=9) newp->dumpTree(cout," _new: ");
// Link in conditional, can blow away temp xor
replaceHandle.relink(newp);
// Added X's, tristate them too
newp->accept(*this);
}
else if (!lvalue) { // Mid-multidimension read, just use zero
// ARRAYSEL(...) -> ARRAYSEL(COND(LT(bit<maxbit), bit, 0))
AstNRelinker replaceHandle;
AstNode* bitp = nodep->bitp()->unlinkFrBack(&replaceHandle);
V3Number zeronum (nodep->fileline(), bitp->width(), 0);
AstNode* newp = new AstCondBound (bitp->fileline(),
condp,
bitp,
new AstConst(bitp->fileline(), zeronum));
// Added X's, tristate them too
if (debug()>=9) newp->dumpTree(cout," _new: ");
replaceHandle.relink(newp);
newp->accept(*this);
}
else { // lvalue
replaceBoundLvalue(nodep, condp);
}
}
}
