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(AstArraySel* nodep, AstNUser*) {
if (!m_assignp) return;
if (nodep->user3()) return; // Prevent recursion on just created nodes
unsigned dim = explicitDimensions(nodep);
AstVarRef* refp = nodep->user1p()->castNode()->castVarRef();
pair<uint32_t,uint32_t> arrDim = refp->varp()->dtypep()->dimensions(false);
uint32_t implicit = (arrDim.second) - dim;
if (implicit > 0) {
AstArraySel* newp = insertImplicit(nodep->cloneTree(false), dim+1, implicit);
nodep->replaceWith(newp); nodep = newp;
nodep->user3(true);
}
int clones = countClones(nodep);
if (m_assignp->user2() > 0 && m_assignp->user2() != clones) {
m_assignp->v3error("Slices of arrays in assignments must have the same unpacked dimensions");
} else if (!m_assignp->user2()) {
if (m_extend && clones > 1 && !m_assignError) {
m_assignp->v3error("Unsupported: Assignment between unpacked arrays of different dimensions");
m_assignError = true;
}
if (clones > 1 && !refp->lvalue() && refp->varp() == m_lhsVarRefp->varp()
&& !m_assignp->castAssignDly() && !m_assignError) {
// LHS Var != RHS Var for a non-delayed assignment
m_assignp->v3error("Unsupported: Slices in a non-delayed assignment with the same Var on both sides");
m_assignError = true;
}
m_assignp->user2(clones);
}
}
virtual void visit(AstPin* nodep, AstNUser*) {
// Check to see if any output pins have __en pins and create the __en pins to match
AstVarRef* refp = findVarRef(nodep);
if (refp && refp->lvalue() && nodep->modVarp()->user1p()) {
AstVar* enchildp = (AstVar*)nodep->modVarp()->user1p();
UINFO(9, " Pulling __en var" << enchildp << endl);
AstVar* enp = new AstVar(enchildp->fileline(),
AstVarType::OUTPUT,
enchildp->name()+cvtToStr(m_unique++),
enchildp);
enp->user2(enchildp->user2());
m_modp->addStmtp(enp);
AstPin* pinp = new AstPin(nodep->fileline(),
nodep->pinNum(),
enp->name(),
new AstVarRef(nodep->fileline(), enp, true));
AstVarRef *rp = findVarRef(pinp);
rp->replaceWith(new AstVarRef(nodep->fileline(), enp, true));
rp->deleteTree(); rp=NULL;
pinp->width(enp->width(),enp->width()); // minwidth==width
pinp->modVarp(enchildp);
m_cellp->addPinsp(pinp);
refp->user1p(enp);
refp->varp()->user1p(enp);
}
// Simplify interconnect in preperation for V3Inst
// (This could be a separate visitor, but we're in the neighborhood)
V3Inst::pinReconnectSimple(nodep, m_cellp, m_modp);
}
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);
}
}
//*******************************************************************
// The following visitor functions deal with detecting Z's in the
// logic, stripping the Z's out and creating an __en signal and its
// logic.
//*******************************************************************
virtual void visit(AstPull* nodep, AstNUser*) {
// replace any pullup/pulldowns with assignw logic and an __en
// signal just like it is any other tristate signal. The only
// difference is that the user2() variable on the __en signal
// will be given a pull direction--i.e. pulldown=1, pullup=2.
// This will signal the driver exansion logic to put a default
// pullup or pulldown state on the tristate bus under the high-Z
// condition when no one is driving the bus. Given the complexity
// of merging tristate drivers at any level, the current limitation
// of this implementation is that a pullup/down gets applied
// to all bits of a bus and a bus cannot have drivers in opposite
// directions on indvidual pins.
AstNode* outp = nodep->lhsp()->unlinkFrBack();;
AstVarRef* outrefp = NULL;
int width=-1;
if (outp->castVarRef()) {
outrefp = outp->castVarRef();
} else if (outp->castSel()) {
outrefp = outp->castSel()->fromp()->castVarRef();
width = outp->castSel()->widthConst();
} else {
nodep->v3error("Can't find LHS varref");
}
outrefp->lvalue(true);
AstVar* varp = outrefp->varp();
if (width==-1) width=varp->width();
V3Number num0 (nodep->fileline(), width);
num0.setAllBits0();
V3Number num1 (nodep->fileline(), width);
num1.setAllBits1();
AstConst* enrhsp = new AstConst(nodep->fileline(), num0);
AstVar* enp = createEnableVar(outp, outrefp, enrhsp, width, "pull");
enp->user2(nodep->direction()+1); // record the pull direction
AstAssignW* newassp = new AstAssignW(nodep->fileline(), outp,
new AstConst(nodep->fileline(), nodep->direction() ? num1 : num0));
nodep->replaceWith(newassp);
nodep->deleteTree(); nodep=NULL;
newassp->iterateChildren(*this);
}