int GaterVertex::sortCmp(const V3GraphVertex* rhsp) const {
const GaterVertex* crhsp = static_cast<const GaterVertex*>(rhsp);
// We really only care about ordering Var's together, but...
// First put same type together
if (typeNum() < crhsp->typeNum()) return -1;
if (typeNum() > crhsp->typeNum()) return 1;
// If variable, group by same input fanin
// (know they're the same type based on above compare)
if (dynamic_cast<const GaterVarVertex*>(this)) {
// We've already sorted by edges, so just see if same tree
// If this gets too slow, we could compute a hash up front
V3GraphEdge* lEdgep = this->inBeginp();
V3GraphEdge* rEdgep = rhsp->inBeginp();
while (lEdgep && rEdgep) {
const GaterEdge* clEdgep = static_cast<const GaterEdge*>(lEdgep);
const GaterEdge* crEdgep = static_cast<const GaterEdge*>(rEdgep);
if (lEdgep->fromp()->rank() < rEdgep->fromp()->rank()) return -1;
if (lEdgep->fromp()->rank() > rEdgep->fromp()->rank()) return 1;
if (clEdgep->ifelse() < crEdgep->ifelse()) return -1;
if (clEdgep->ifelse() > crEdgep->ifelse()) return 1;
lEdgep = lEdgep->inNextp();
rEdgep = rEdgep->inNextp();
}
if (!lEdgep && !rEdgep) return 0;
return lEdgep ? -1 : 1;
}
// Finally by rank of this vertex
if (rank() < rhsp->rank()) return -1;
if (rank() > rhsp->rank()) return 1;
return 0;
}
// Returns only the result from the LAST vertex iterated over
AstNUser* iterateInEdges(GateGraphBaseVisitor& v, AstNUser* vup=NULL) {
AstNUser* retp = NULL;
for (V3GraphEdge* edgep = inBeginp(); edgep; edgep = edgep->inNextp()) {
retp = dynamic_cast<GateEitherVertex*>(edgep->fromp())->accept(v, vup);
}
return retp;
}
void nafgMarkRecurse(V3GraphVertex* vertexp, uint32_t generation) {
// Backwards mark user() on the path we recurse
//UINFO(9," nafgMark: v "<<(void*)(vertexp)<<" "<<vertexp->name()<<endl);
for (V3GraphEdge* edgep = vertexp->inBeginp(); edgep; edgep = edgep->inNextp()) {
//UINFO(9," nafgMark: "<<(void*)(edgep)<<" "<<edgep->name()<<endl);
edgep->user(generation);
nafgMarkRecurse(edgep->fromp(), generation);
}
}
void GateVisitor::consumedMarkRecurse(GateEitherVertex* vertexp) {
if (vertexp->user()) return; // Already marked
vertexp->user(true);
if (!vertexp->consumed()) vertexp->setConsumed("propagated");
// Walk sources and mark them too
for (V3GraphEdge* edgep = vertexp->inBeginp(); edgep; edgep = edgep->inNextp()) {
GateEitherVertex* eFromVertexp = (GateEitherVertex*)edgep->fromp();
consumedMarkRecurse(eFromVertexp);
}
}
uint32_t V3GraphVertex::inHash() const {
// We want the same hash ignoring the order of edges.
// So we need an associative operator, like XOR.
// However with XOR multiple edges to the same source will cancel out,
// so we use ADD. (Generally call this only after removing duplicates though)
uint32_t hash=0;
for (V3GraphEdge* edgep = this->inBeginp(); edgep; edgep=edgep->inNextp()) {
hash += cvtToHash(edgep->fromp());
}
return hash;
}
void V3GraphVertex::rerouteEdges(V3Graph* graphp) {
// Make new edges for each from/to pair
for (V3GraphEdge* iedgep = inBeginp(); iedgep; iedgep=iedgep->inNextp()) {
for (V3GraphEdge* oedgep = outBeginp(); oedgep; oedgep=oedgep->outNextp()) {
new V3GraphEdge (graphp, iedgep->fromp(), oedgep->top(),
min(iedgep->weight(),oedgep->weight()),
iedgep->cutable() && oedgep->cutable());
}
}
// Remove old edges
unlinkEdges(graphp);
}
void V3GraphVertex::unlinkEdges(V3Graph* graphp) {
for (V3GraphEdge* edgep = outBeginp(); edgep; /*BELOW*/) {
V3GraphEdge* nextp = edgep->outNextp();
edgep->unlinkDelete();
edgep = nextp;
}
for (V3GraphEdge* edgep = inBeginp(); edgep; /*BELOW*/) {
V3GraphEdge* nextp = edgep->inNextp();
edgep->unlinkDelete();
edgep = nextp;
}
}
void V3Graph::dump(ostream& os) {
// This generates a file used by graphviz, http://www.graphviz.org
os<<" Graph:\n";
// Print vertices
for (V3GraphVertex* vertexp = verticesBeginp(); vertexp; vertexp=vertexp->verticesNextp()) {
os<<"\tNode: "<<vertexp->name();
if (vertexp->color()) os<<" color="<<vertexp->color();
os<<endl;
// Print edges
for (V3GraphEdge* edgep = vertexp->inBeginp(); edgep; edgep=edgep->inNextp()) {
dumpEdge (os, vertexp, edgep);
}
for (V3GraphEdge* edgep = vertexp->outBeginp(); edgep; edgep=edgep->outNextp()) {
dumpEdge (os, vertexp, edgep);
}
}
}
void pruneDepsOnInputs() {
for (V3GraphVertex* vertexp = m_graph.verticesBeginp();
vertexp; vertexp=vertexp->verticesNextp()) {
if (!vertexp->outBeginp()
&& dynamic_cast<SplitVarStdVertex*>(vertexp)) {
if (debug() >= 9) {
SplitVarStdVertex* stdp = (SplitVarStdVertex*)(vertexp);
UINFO(0, "Will prune deps on var "<<stdp->nodep()<<endl);
stdp->nodep()->dumpTree(cout, "- ");
}
for (V3GraphEdge* edgep = vertexp->inBeginp();
edgep; edgep=edgep->inNextp()) {
SplitEdge* oedgep = dynamic_cast<SplitEdge*>(edgep);
oedgep->setIgnoreThisStep();
}
}
}
}
void optimize_no_outbound() {
// Non-accepting states with no outbound transitions may be
// deleted. Then, any arcs feeding those states, and perhaps those
// states...
// Vertex::m_user begin: 1 indicates on the work list
// (Otherwise we might have nodes on the list twice, and reference after deleting them.)
m_graphp->userClearVertices();
// Find all dead vertexes
stack<DfaVertex*> workps;
for (V3GraphVertex* vertexp = m_graphp->verticesBeginp(); vertexp; vertexp=vertexp->verticesNextp()) {
if (DfaVertex* vvertexp = dynamic_cast<DfaVertex*>(vertexp)) {
workps.push(vvertexp);
vertexp->user(1);
} else {
// If ever remove this, need dyn cast below
v3fatalSrc("Non DfaVertex in dfa graph");
}
}
// While deadness... Delete and find new dead nodes.
while (!workps.empty()) {
DfaVertex* vertexp = workps.top(); workps.pop();
vertexp->user(0);
if (isDead(vertexp)) {
// Add nodes that go here to the work list
for (V3GraphEdge* edgep = vertexp->inBeginp(); edgep; edgep=edgep->inNextp()) {
DfaVertex* fromvertexp = static_cast<DfaVertex*>(edgep->fromp());
if (fromvertexp != vertexp
&& !fromvertexp->user()) {
workps.push(static_cast<DfaVertex*>(fromvertexp));
fromvertexp->user(1);
}
}
// Transitions to this state removed by the unlink function
vertexp->unlinkDelete(m_graphp); vertexp=NULL;
}
}
}
void colorAlwaysGraph() {
// Color the graph to indicate subsets, each of which
// we can split into its own always block.
m_graph.removeRedundantEdges(&V3GraphEdge::followAlwaysTrue);
// Some vars are primary inputs to the always block; prune
// edges on those vars. Reasoning: if two statements both depend
// on primary input A, it's ok to split these statements. Whereas
// if they both depend on locally-generated variable B, the statements
// must be kept together.
SplitEdge::incrementStep();
pruneDepsOnInputs();
// For any 'if' node whose deps have all been pruned
// (meaning, its conditional expression only looks at primary
// inputs) prune all edges that depend on the 'if'.
for (V3GraphVertex* vertexp = m_graph.verticesBeginp();
vertexp; vertexp=vertexp->verticesNextp()) {
SplitLogicVertex* logicp = dynamic_cast<SplitLogicVertex*>(vertexp);
if (!logicp) continue;
AstNodeIf* ifNodep = VN_CAST(logicp->nodep(), NodeIf);
if (!ifNodep) continue;
bool pruneMe = true;
for (V3GraphEdge* edgep = logicp->outBeginp();
edgep; edgep = edgep->outNextp()) {
SplitEdge* oedgep = dynamic_cast<SplitEdge*>(edgep);
if (!oedgep->ignoreThisStep()) {
// This if conditional depends on something we can't
// prune -- a variable generated in the current block.
pruneMe = false;
// When we can't prune dependencies on the conditional,
// give a hint about why...
if (debug() >= 9) {
V3GraphVertex* vxp = oedgep->top();
SplitNodeVertex* nvxp = dynamic_cast<SplitNodeVertex*>(vxp);
UINFO(0, "Cannot prune if-node due to edge "<<oedgep<<
" pointing to node "<<nvxp->nodep()<<endl);
nvxp->nodep()->dumpTree(cout, "- ");
}
break;
}
}
if (!pruneMe) continue;
// This if can be split; prune dependencies on it.
for (V3GraphEdge* edgep = logicp->inBeginp();
edgep; edgep = edgep->inNextp()) {
SplitEdge* oedgep = dynamic_cast<SplitEdge*>(edgep);
oedgep->setIgnoreThisStep();
}
}
if (debug()>=9) {
m_graph.dumpDotFilePrefixed("splitg_nodup", false);
}
// Weak coloring to determine what needs to remain grouped
// in a single always. This follows all edges excluding:
// - those we pruned above
// - PostEdges, which are done later
m_graph.weaklyConnected(&SplitEdge::followScoreboard);
}
void cleanupBlockGraph(AstNode* nodep) {
// Transform the graph into what we need
UINFO(5, "ReorderBlock "<<nodep<<endl);
m_graph.removeRedundantEdges(&V3GraphEdge::followAlwaysTrue);
if (debug()>=9) {
m_graph.dumpDotFilePrefixed("reorderg_nodup", false);
//m_graph.dump(); cout<<endl;
}
// Mark all the logic for this step
// Vertex::m_user begin: true indicates logic for this step
m_graph.userClearVertices();
for (AstNode* nextp=nodep; nextp; nextp=nextp->nextp()) {
SplitLogicVertex* vvertexp = (SplitLogicVertex*)nextp->user3p();
vvertexp->user(true);
}
// If a var vertex has only inputs, it's a input-only node,
// and can be ignored for coloring **this block only**
SplitEdge::incrementStep();
pruneDepsOnInputs();
// For reordering this single block only, mark all logic
// vertexes not involved with this step as unimportant
for (V3GraphVertex* vertexp = m_graph.verticesBeginp(); vertexp; vertexp=vertexp->verticesNextp()) {
if (SplitLogicVertex* vvertexp = dynamic_cast<SplitLogicVertex*>(vertexp)) {
if (!vvertexp->user()) {
for (V3GraphEdge* edgep = vertexp->inBeginp(); edgep; edgep=edgep->inNextp()) {
SplitEdge* oedgep = dynamic_cast<SplitEdge*>(edgep);
oedgep->setIgnoreThisStep();
}
for (V3GraphEdge* edgep = vertexp->outBeginp(); edgep; edgep=edgep->outNextp()) {
SplitEdge* oedgep = dynamic_cast<SplitEdge*>(edgep);
oedgep->setIgnoreThisStep();
}
}
}
}
// Weak coloring to determine what needs to remain in order
// This follows all step-relevant edges excluding PostEdges, which are done later
m_graph.weaklyConnected(&SplitEdge::followScoreboard);
// Add hard orderings between all nodes of same color, in the order they appeared
vl_unordered_map<uint32_t, SplitLogicVertex*> lastOfColor;
for (AstNode* nextp=nodep; nextp; nextp=nextp->nextp()) {
SplitLogicVertex* vvertexp = (SplitLogicVertex*)nextp->user3p();
uint32_t color = vvertexp->color();
if (!color) nextp->v3fatalSrc("No node color assigned");
if (lastOfColor[color]) {
new SplitStrictEdge(&m_graph, lastOfColor[color], vvertexp);
}
lastOfColor[color] = vvertexp;
}
// And a real ordering to get the statements into something reasonable
// We don't care if there's cutable violations here...
// Non-cutable violations should be impossible; as those edges are program-order
if (debug()>=9) m_graph.dumpDotFilePrefixed((string)"splitg_preo", false);
m_graph.acyclic(&SplitEdge::followCyclic);
m_graph.rank(&SplitEdge::followCyclic); // Or order(), but that's more expensive
if (debug()>=9) m_graph.dumpDotFilePrefixed((string)"splitg_opt", false);
}
void GateVisitor::optimizeSignals(bool allowMultiIn) {
for (V3GraphVertex* itp = m_graph.verticesBeginp(); itp; itp=itp->verticesNextp()) {
if (GateVarVertex* vvertexp = dynamic_cast<GateVarVertex*>(itp)) {
if (vvertexp->inEmpty()) {
vvertexp->clearReducibleAndDedupable("inEmpty"); // Can't deal with no sources
if (!vvertexp->isTop() // Ok if top inputs are driverless
&& !vvertexp->varScp()->varp()->valuep()
&& !vvertexp->varScp()->varp()->isSigPublic()) {
UINFO(4, "No drivers "<<vvertexp->varScp()<<endl);
if (0) {
// If we warned here after constant propagation, what the user considered
// reasonable logic may have disappeared. Issuing a warning would
// thus be confusing. V3Undriven now handles this.
vvertexp->varScp()->varp()->v3warn(UNDRIVEN,"Signal has no drivers "
<<vvertexp->scopep()->prettyName()<<"."
<<vvertexp->varScp()->varp()->prettyName());
}
}
}
else if (!vvertexp->inSize1()) {
vvertexp->clearReducibleAndDedupable("size!1"); // Can't deal with more than one src
}
// Reduce it?
if (!vvertexp->reducible()) {
UINFO(8, "SigNotRed "<<vvertexp->name()<<endl);
} else {
UINFO(8, "Sig "<<vvertexp->name()<<endl);
GateLogicVertex* logicVertexp = dynamic_cast<GateLogicVertex*>
(vvertexp->inBeginp()->fromp());
UINFO(8, " From "<<logicVertexp->name()<<endl);
AstNode* logicp = logicVertexp->nodep();
if (logicVertexp->reducible()) {
// Can we eliminate?
GateOkVisitor okVisitor(logicp, vvertexp->isClock(), false);
bool multiInputs = okVisitor.rhsVarRefs().size() > 1;
// Was it ok?
bool doit = okVisitor.isSimple();
if (doit && multiInputs) {
if (!allowMultiIn) doit = false;
// Doit if one input, or not used, or used only once, ignoring traces
int n=0;
for (V3GraphEdge* edgep = vvertexp->outBeginp(); edgep; edgep = edgep->outNextp()) {
GateLogicVertex* consumeVertexp = dynamic_cast<GateLogicVertex*>(edgep->top());
if (!consumeVertexp->slow()) { // Not tracing or other slow path junk
if (edgep->top()->outBeginp()) { // Destination is itself used
n += edgep->weight();
}
}
if (n>1) {
doit = false;
break;
}
}
}
// Process it
if (!doit) {
if (allowMultiIn && (debug()>=9)) {
UINFO(9, "Not ok simp"<<okVisitor.isSimple()<<" mi"<<multiInputs
<<" ob"<<vvertexp->outBeginp()<<" on"<<(vvertexp->outBeginp()?vvertexp->outBeginp()->outNextp():0)
<<" "<<vvertexp->name()
<<endl);
for (V3GraphEdge* edgep = vvertexp->outBeginp(); edgep; edgep = edgep->outNextp()) {
GateLogicVertex* consumeVertexp = dynamic_cast<GateLogicVertex*>(edgep->top());
UINFO(9, " edge "<<edgep<<" to: "<<consumeVertexp->nodep()<<endl);
}
for (V3GraphEdge* edgep = vvertexp->inBeginp(); edgep; edgep = edgep->inNextp()) {
GateLogicVertex* consumeVertexp = dynamic_cast<GateLogicVertex*>(edgep->fromp());
UINFO(9, " edge "<<edgep<<" from: "<<consumeVertexp->nodep()<<endl);
}
}
}
else {
AstNode* substp = okVisitor.substTree();
if (debug()>=5) logicp->dumpTree(cout,"\telimVar: ");
if (debug()>=5) substp->dumpTree(cout,"\t subst: ");
++m_statSigs;
bool removedAllUsages = true;
for (V3GraphEdge* edgep = vvertexp->outBeginp();
edgep; ) {
GateLogicVertex* consumeVertexp = dynamic_cast<GateLogicVertex*>(edgep->top());
AstNode* consumerp = consumeVertexp->nodep();
if (!elimLogicOkOutputs(consumeVertexp, okVisitor/*ref*/)) {
// Cannot optimize this replacement
removedAllUsages = false;
edgep = edgep->outNextp();
} else {
optimizeElimVar(vvertexp->varScp(), substp, consumerp);
// If the new replacement referred to a signal,
// Correct the graph to point to this new generating variable
const GateVarRefList& rhsVarRefs = okVisitor.rhsVarRefs();
for (GateVarRefList::const_iterator it = rhsVarRefs.begin();
it != rhsVarRefs.end(); ++it) {
AstVarScope* newvarscp = (*it)->varScopep();
UINFO(9," Point-to-new vertex "<<newvarscp<<endl);
GateVarVertex* varvertexp = makeVarVertex(newvarscp);
new V3GraphEdge(&m_graph, varvertexp, consumeVertexp, 1);
// Propagate clock attribute onto generating node
varvertexp->propagateAttrClocksFrom(vvertexp);
}
// Remove the edge
edgep->unlinkDelete(); VL_DANGLING(edgep);
++m_statRefs;
edgep = vvertexp->outBeginp();
}
}
if (removedAllUsages) {
// Remove input links
while (V3GraphEdge* edgep = vvertexp->inBeginp()) {
edgep->unlinkDelete(); VL_DANGLING(edgep);
}
// Clone tree so we remember it for tracing, and keep the pointer
// to the "ALWAYS" part of the tree as part of this statement
// That way if a later signal optimization that retained a pointer to the always
// can optimize it further
logicp->unlinkFrBack();
vvertexp->varScp()->valuep(logicp);
logicp = NULL;
// Mark the vertex so we don't mark it as being unconsumed in the next step
vvertexp->user(true);
logicVertexp->user(true);
}
}
}
}
}
}
}
virtual AstNUser* visit(GateVarVertex *vvertexp, AstNUser*) {
for (V3GraphEdge* edgep = vvertexp->inBeginp(); edgep; ) {
V3GraphEdge* oldedgep = edgep;
edgep = edgep->inNextp(); // for recursive since the edge could be deleted
if (GateLogicVertex* lvertexp = dynamic_cast<GateLogicVertex*>(oldedgep->fromp())) {
if (AstNodeAssign* assignp = lvertexp->nodep()->castNodeAssign()) {
//if (lvertexp->outSize1() && assignp->lhsp()->castSel()) {
if (assignp->lhsp()->castSel() && lvertexp->outSize1()) {
UINFO(9, "assing to the nodep["<<assignp->lhsp()->castSel()->lsbConst()<<"]"<<endl);
// first assign with Sel-lhs
if (!m_activep) m_activep = lvertexp->activep();
if (!m_logicvp) m_logicvp = lvertexp;
if (!m_assignp) m_assignp = assignp;
// not under the same active
if (m_activep != lvertexp->activep()) {
m_activep = lvertexp->activep();
m_logicvp = lvertexp;
m_assignp = assignp;
continue;
}
AstSel* preselp = m_assignp->lhsp()->castSel();
AstSel* curselp = assignp->lhsp()->castSel();
if (!preselp || !curselp) continue;
if (AstSel* newselp = merge(preselp, curselp)) {
UINFO(5, "assemble to new sel: "<<newselp<<endl);
// replace preSel with newSel
preselp->replaceWith(newselp); preselp->deleteTree(); VL_DANGLING(preselp);
// create new rhs for pre assignment
AstNode* newrhsp = new AstConcat(m_assignp->rhsp()->fileline(), m_assignp->rhsp()->cloneTree(false), assignp->rhsp()->cloneTree(false));
AstNode* oldrhsp = m_assignp->rhsp();
oldrhsp->replaceWith(newrhsp); oldrhsp->deleteTree(); VL_DANGLING(oldrhsp);
m_assignp->dtypeChgWidthSigned(m_assignp->width()+assignp->width(), m_assignp->width()+assignp->width(), AstNumeric::fromBool(true));
// don't need to delete, will be handled
//assignp->unlinkFrBack(); assignp->deleteTree(); VL_DANGLING(assignp);
// update the graph
{
// delete all inedges to lvertexp
if (!lvertexp->inEmpty()) {
for (V3GraphEdge* ledgep = lvertexp->inBeginp(); ledgep; ) {
V3GraphEdge* oedgep = ledgep;
ledgep = ledgep->inNextp();
GateEitherVertex* fromvp = dynamic_cast<GateEitherVertex*>(oedgep->fromp());
new V3GraphEdge(m_graphp, fromvp, m_logicvp, 1);
oedgep->unlinkDelete(); VL_DANGLING(oedgep);
}
}
// delete all outedges to lvertexp, only one
oldedgep->unlinkDelete(); VL_DANGLING(oldedgep);
}
++m_numMergedAssigns;
} else {
m_assignp = assignp;
m_logicvp = lvertexp;
}
}
}
}
}
return NULL;
}
