virtual void visit(AstSel* nodep, AstNUser*) {
AstVarRef* varrefp = nodep->fromp()->castVarRef();
AstConst* constp = nodep->lsbp()->castConst();
if (varrefp && constp && !constp->num().isFourState()) {
UndrivenVarEntry* entryp = getEntryp (varrefp->varp());
int lsb = constp->toUInt();
if (m_markBoth || varrefp->lvalue()) entryp->drivenBit(lsb, nodep->width());
if (m_markBoth || !varrefp->lvalue()) entryp->usedBit(lsb, nodep->width());
} else {
// else other varrefs handled as unknown mess in AstVarRef
nodep->iterateChildren(*this);
}
}
virtual void visit(AstSel* nodep, AstNUser*) {
AstVarRef* varrefp = nodep->fromp()->castVarRef();
AstConst* constp = nodep->lsbp()->castConst();
if (varrefp && constp && !constp->num().isFourState()) {
for (int usr=1; usr<(m_alwaysp?3:2); ++usr) {
UndrivenVarEntry* entryp = getEntryp (varrefp->varp(), usr);
int lsb = constp->toUInt();
if (m_markBoth || varrefp->lvalue()) {
// Don't warn if already driven earlier as "a=0; if(a) a=1;" is fine.
if (usr==2 && m_alwaysp && entryp->isUsedNotDrivenBit(lsb, nodep->width())) {
UINFO(9," Select. Entryp="<<(void*)entryp<<endl);
warnAlwCombOrder(varrefp);
}
entryp->drivenBit(lsb, nodep->width());
}
if (m_markBoth || !varrefp->lvalue()) entryp->usedBit(lsb, nodep->width());
}
} else {
// else other varrefs handled as unknown mess in AstVarRef
nodep->iterateChildren(*this);
}
}
virtual void visit(AstNodeAssign* nodep) {
if (!m_cfuncp) return;
// Left select WordSel or ArraySel
AstNodeSel* lselp = VN_CAST(nodep->lhsp(), NodeSel);
if (!lselp) { mergeEnd(); return; } // Not ever merged
// Of a constant index
AstConst* lbitp = VN_CAST(lselp->bitp(), Const);
if (!lbitp) { mergeEnd(); return; }
uint32_t index = lbitp->toUInt();
// Of variable
AstNodeVarRef* lvarrefp = VN_CAST(lselp->fromp(), NodeVarRef);
if (!lvarrefp) { mergeEnd(); return; }
// RHS is a constant or a select
AstConst* rconstp = VN_CAST(nodep->rhsp(), Const);
AstNodeSel* rselp = VN_CAST(nodep->rhsp(), NodeSel);
AstNodeVarRef* rvarrefp = NULL;
if (rconstp) { // Ok
} else {
if (!rselp) { mergeEnd(); return; }
AstConst* rbitp = VN_CAST(rselp->bitp(), Const);
rvarrefp = VN_CAST(rselp->fromp(), NodeVarRef);
if (!rbitp || rbitp->toUInt() != index
|| !rvarrefp
|| lvarrefp->varp() == rvarrefp->varp()) {
mergeEnd(); return;
}
}
if (m_mgSelLp) { // Old merge
if (m_mgCfuncp == m_cfuncp
&& m_mgNextp == nodep
&& m_mgSelLp->same(lselp)
&& m_mgVarrefLp->same(lvarrefp)
&& (m_mgConstRp
? (rconstp && m_mgConstRp->same(rconstp))
: (rselp
&& m_mgSelRp->same(rselp)
&& m_mgVarrefRp->same(rvarrefp)))
&& (index == m_mgIndexLo-1
|| index == m_mgIndexHi+1)) {
// Sequentially next to last assign; continue merge
if (index == m_mgIndexLo-1) m_mgIndexLo = index;
else if (index == m_mgIndexHi+1) m_mgIndexHi = index;
UINFO(9, "Continue merge i="<<index
<<" "<<m_mgIndexHi<<":"<<m_mgIndexLo<<" "<<nodep<<endl);
m_mgAssignps.push_back(nodep);
m_mgNextp = nodep->nextp();
return;
}
else {
// This assign doesn't merge with previous assign,
// but should start a new merge
mergeEnd();
}
}
// Merge start
m_mgAssignps.push_back(nodep);
m_mgCfuncp = m_cfuncp;
m_mgNextp = nodep->nextp();
m_mgSelLp = lselp;
m_mgSelRp = rselp;
m_mgVarrefLp = lvarrefp;
m_mgVarrefRp = rvarrefp;
m_mgConstRp = rconstp;
m_mgIndexLo = index;
m_mgIndexHi = index;
UINFO(9, "Start merge i="<<index<<" "<<nodep<<endl);
}