virtual void visit(AstSelBit* nodep, AstNUser*) {
// Select of a non-width specified part of an array, i.e. "array[2]"
// This select style has a lsb and msb (no user specified width)
UINFO(6,"SELBIT "<<nodep<<endl);
if (debug()>=9) nodep->backp()->dumpTree(cout,"--SELBT0: ");
// lhsp/rhsp do not need to be constant
AstNode* fromp = nodep->lhsp()->unlinkFrBack();
AstNode* rhsp = nodep->rhsp()->unlinkFrBack(); // bit we're extracting
if (debug()>=9) nodep->dumpTree(cout,"--SELBT2: ");
FromData fromdata = fromDataForArray(nodep, fromp, false);
AstNodeDType* ddtypep = fromdata.m_dtypep;
VNumRange fromRange = fromdata.m_fromRange;
UINFO(6," ddtypep "<<ddtypep<<endl);
if (AstUnpackArrayDType* adtypep = ddtypep->castUnpackArrayDType()) {
// SELBIT(array, index) -> ARRAYSEL(array, index)
AstNode* subp = rhsp;
if (fromRange.lo()!=0 || fromRange.hi()<0) {
subp = newSubNeg (subp, fromRange.lo());
}
AstArraySel* newp = new AstArraySel (nodep->fileline(),
fromp, subp);
newp->dtypeFrom(adtypep->subDTypep()); // Need to strip off array reference
if (debug()>=9) newp->dumpTree(cout,"--SELBTn: ");
nodep->replaceWith(newp); pushDeletep(nodep); VL_DANGLING(nodep);
}
else if (AstPackArrayDType* adtypep = ddtypep->castPackArrayDType()) {
// SELBIT(array, index) -> SEL(array, index*width-of-subindex, width-of-subindex)
AstNode* subp = rhsp;
if (fromRange.lo()!=0 || fromRange.hi()<0) {
subp = newSubNeg (subp, fromRange.lo());
}
if (!fromRange.elements() || (adtypep->width() % fromRange.elements())!=0)
adtypep->v3fatalSrc("Array extraction with width miscomputed "
<<adtypep->width()<<"/"<<fromRange.elements());
int elwidth = adtypep->width() / fromRange.elements();
AstSel* newp = new AstSel (nodep->fileline(),
fromp,
new AstMul(nodep->fileline(),
new AstConst(nodep->fileline(),AstConst::Unsized32(),elwidth),
subp),
new AstConst (nodep->fileline(),AstConst::Unsized32(),elwidth));
newp->declRange(fromRange);
newp->declElWidth(elwidth);
newp->dtypeFrom(adtypep->subDTypep()); // Need to strip off array reference
if (debug()>=9) newp->dumpTree(cout,"--SELBTn: ");
nodep->replaceWith(newp); pushDeletep(nodep); VL_DANGLING(nodep);
}
else if (ddtypep->castBasicDType()) {
// SELBIT(range, index) -> SEL(array, index, 1)
AstSel* newp = new AstSel (nodep->fileline(),
fromp,
newSubLsbOf(rhsp, fromRange),
// Unsized so width from user
new AstConst (nodep->fileline(),AstConst::Unsized32(),1));
newp->declRange(fromRange);
UINFO(6," new "<<newp<<endl);
if (debug()>=9) newp->dumpTree(cout,"--SELBTn: ");
nodep->replaceWith(newp); pushDeletep(nodep); VL_DANGLING(nodep);
}
else if (ddtypep->castNodeClassDType()) { // It's packed, so a bit from the packed struct
// SELBIT(range, index) -> SEL(array, index, 1)
AstSel* newp = new AstSel (nodep->fileline(),
fromp,
newSubLsbOf(rhsp, fromRange),
// Unsized so width from user
new AstConst (nodep->fileline(),AstConst::Unsized32(),1));
newp->declRange(fromRange);
UINFO(6," new "<<newp<<endl);
if (debug()>=9) newp->dumpTree(cout,"--SELBTn: ");
nodep->replaceWith(newp); pushDeletep(nodep); VL_DANGLING(nodep);
}
else { // NULL=bad extract, or unknown node type
nodep->v3error("Illegal bit or array select; type already selected, or bad dimension: type is"
<<fromdata.m_errp->prettyName());
// How to recover? We'll strip a dimension.
nodep->replaceWith(fromp); pushDeletep(nodep); VL_DANGLING(nodep);
}
if (!rhsp->backp()) { pushDeletep(rhsp); VL_DANGLING(rhsp); }
}
