AstArraySel* insertImplicit(AstNode* nodep, unsigned start, unsigned count) {
// Insert any implicit slices as explicit slices (ArraySel nodes).
// Return a new pointer to replace nodep() in the ArraySel.
UINFO(9," insertImplicit (start="<<start<<",c="<<count<<") "<<nodep<<endl);
AstVarRef* refp = nodep->user1p()->castNode()->castVarRef();
if (!refp) nodep->v3fatalSrc("No VarRef in user1 of node "<<nodep);
AstVar* varp = refp->varp();
AstNode* topp = nodep;
for (unsigned i = start; i < start + count; ++i) {
AstNodeDType* dtypep = varp->dtypep()->dtypeDimensionp(i-1);
AstUnpackArrayDType* adtypep = dtypep->castUnpackArrayDType();
if (!adtypep) nodep->v3fatalSrc("insertImplicit tried to expand an array without an ArrayDType");
vlsint32_t msb = adtypep->msb();
vlsint32_t lsb = adtypep->lsb();
if (lsb > msb) {
// Below code assumes big bit endian; just works out if we swap
int x = msb; msb = lsb; lsb = x;
}
UINFO(9," ArraySel-child: "<<topp<<endl);
AstArraySel* newp = new AstArraySel(nodep->fileline(), topp,
// "lsb-lsb": Arrays are zero-based so index 0 is always lsb
new AstConst(nodep->fileline(), lsb-lsb));
if (!newp->dtypep()) {
newp->v3fatalSrc("ArraySel dtyping failed when resolving slice"); // see ArraySel constructor
}
newp->user1p(refp);
newp->start(lsb);
newp->length(msb - lsb + 1);
topp = newp;
}
return topp->castArraySel();
}
virtual void visit(AstSelExtract* nodep, AstNUser*) {
// Select of a range specified part of an array, i.e. "array[2:3]"
// SELEXTRACT(from,msb,lsb) -> SEL(from, lsb, 1+msb-lsb)
// This select style has a (msb or lsb) and width
UINFO(6,"SELEXTRACT "<<nodep<<endl);
//if (debug()>=9) nodep->dumpTree(cout,"--SELEX0: ");
// Below 2 lines may change nodep->widthp()
V3Const::constifyParamsEdit(nodep->lsbp()); // May relink pointed to node
V3Const::constifyParamsEdit(nodep->msbp()); // May relink pointed to node
//if (debug()>=9) nodep->dumpTree(cout,"--SELEX3: ");
checkConstantOrReplace(nodep->lsbp(), "First value of [a:b] isn't a constant, maybe you want +: or -:");
checkConstantOrReplace(nodep->msbp(), "Second value of [a:b] isn't a constant, maybe you want +: or -:");
AstNode* fromp = nodep->lhsp()->unlinkFrBack();
AstNode* msbp = nodep->rhsp()->unlinkFrBack();
AstNode* lsbp = nodep->thsp()->unlinkFrBack();
vlsint32_t msb = msbp->castConst()->toSInt();
vlsint32_t lsb = lsbp->castConst()->toSInt();
FromData fromdata = fromDataForArray(nodep, fromp, false);
AstNodeDType* ddtypep = fromdata.m_dtypep;
VNumRange fromRange = fromdata.m_fromRange;
if (ddtypep->castUnpackArrayDType()) {
// Slice extraction
if (fromRange.elements() == (msb-lsb+1)
&& fromRange.lo() == lsb) { // Extracting whole of original array
nodep->replaceWith(fromp); pushDeletep(nodep); VL_DANGLING(nodep);
} else {
// TODO when unpacked arrays fully supported probably need new data type here
AstArraySel* newp = new AstArraySel (nodep->fileline(), fromp, lsbp);
newp->start(lsb);
newp->length((msb - lsb) + 1);
nodep->replaceWith(newp); pushDeletep(nodep); VL_DANGLING(nodep);
}
}
else if (AstPackArrayDType* adtypep = ddtypep->castPackArrayDType()) {
// SELEXTRACT(array, msb, lsb) -> SEL(array, lsb*width-of-subindex, width-of-subindex*(msb-lsb))
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 AstConst(nodep->fileline(),AstConst::Unsized32(),lsb*elwidth),
new AstConst(nodep->fileline(),AstConst::Unsized32(),(msb-lsb+1)*elwidth));
newp->declRange(fromRange);
newp->declElWidth(elwidth);
newp->dtypeFrom(sliceDType(adtypep, msb, lsb));
//if (debug()>=9) newp->dumpTree(cout,"--EXTBTn: ");
if (newp->widthMin()!=(int)newp->widthConst()) nodep->v3fatalSrc("Width mismatch");
nodep->replaceWith(newp); pushDeletep(nodep); VL_DANGLING(nodep);
}
else if (ddtypep->castBasicDType()) {
if (fromRange.littleEndian()) {
// Below code assumes big bit endian; just works out if we swap
int x = msb; msb = lsb; lsb = x;
}
if (lsb > msb) {
nodep->v3error("["<<msb<<":"<<lsb<<"] Range extract has backward bit ordering, perhaps you wanted ["<<lsb<<":"<<msb<<"]");
int x = msb; msb = lsb; lsb = x;
}
AstNode* widthp = new AstConst (msbp->fileline(), AstConst::Unsized32(), // Unsized so width from user
msb +1-lsb);
AstSel* newp = new AstSel (nodep->fileline(),
fromp,
newSubLsbOf(lsbp, fromRange),
widthp);
newp->declRange(fromRange);
UINFO(6," new "<<newp<<endl);
//if (debug()>=9) newp->dumpTree(cout,"--SELEXnew: ");
nodep->replaceWith(newp); pushDeletep(nodep); VL_DANGLING(nodep);
}
else if (ddtypep->castNodeClassDType()) {
// Classes aren't little endian
if (lsb > msb) {
nodep->v3error("["<<msb<<":"<<lsb<<"] Range extract has backward bit ordering, perhaps you wanted ["<<lsb<<":"<<msb<<"]");
int x = msb; msb = lsb; lsb = x;
}
AstNode* widthp = new AstConst (msbp->fileline(), AstConst::Unsized32(), // Unsized so width from user
msb +1-lsb);
AstSel* newp = new AstSel (nodep->fileline(),
fromp,
newSubLsbOf(lsbp, fromRange),
widthp);
newp->declRange(fromRange);
UINFO(6," new "<<newp<<endl);
//if (debug()>=9) newp->dumpTree(cout,"--SELEXnew: ");
nodep->replaceWith(newp); pushDeletep(nodep); VL_DANGLING(nodep);
}
else { // NULL=bad extract, or unknown node type
nodep->v3error("Illegal range select; type already selected, or bad dimension: type is "
<<fromdata.m_errp->prettyName());
UINFO(1," Related ddtype: "<<ddtypep<<endl);
// How to recover? We'll strip a dimension.
nodep->replaceWith(fromp); pushDeletep(nodep); VL_DANGLING(nodep);
}
// delete whataver we didn't use in reconstruction
if (!fromp->backp()) { pushDeletep(fromp); VL_DANGLING(fromp); }
if (!msbp->backp()) { pushDeletep(msbp); VL_DANGLING(msbp); }
if (!lsbp->backp()) { pushDeletep(lsbp); VL_DANGLING(lsbp); }
}
