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 combineGraph(const TspGraphTmpl& g) {
vl_unordered_set<vluint32_t> edges_done;
for (V3GraphVertex* vxp = g.verticesBeginp(); vxp; vxp = vxp->verticesNextp()) {
Vertex* fromp = castVertexp(vxp);
for (V3GraphEdge* edgep = fromp->outBeginp(); edgep; edgep = edgep->outNextp()) {
Vertex* top = castVertexp(edgep->top());
if (edges_done.find(edgep->user()) == edges_done.end()) {
addEdge(fromp->key(), top->key(), edgep->weight());
edges_done.insert(edgep->user());
}
}
}
}
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);
}
}
}
}
}
}
}
void V3Graph::dumpDotFile(const string& filename, bool colorAsSubgraph) {
// This generates a file used by graphviz, http://www.graphviz.org
// "hardcoded" parameters:
const auto_ptr<ofstream> logp (V3File::new_ofstream(filename));
if (logp->fail()) v3fatalSrc("Can't write "<<filename);
// Header
*logp<<"digraph v3graph {\n";
*logp<<"\tgraph\t[label=\""<<filename<<"\",\n";
*logp<<"\t\t labelloc=t, labeljust=l,\n";
*logp<<"\t\t //size="<<"\"7.5,10\","<<"\n";
*logp<<"\t\t rankdir="<<dotRankDir()<<"];\n";
// List of all possible subgraphs
typedef multimap<string,V3GraphVertex*> SubgraphMmap;
SubgraphMmap subgraphs;
for (V3GraphVertex* vertexp = verticesBeginp(); vertexp; vertexp=vertexp->verticesNextp()) {
string vertexSubgraph = (colorAsSubgraph && vertexp->color()) ? cvtToStr(vertexp->color()) : "";
subgraphs.insert(make_pair(vertexSubgraph, vertexp));
}
// We use a map here, as we don't want to corrupt anything (userp) in the graph,
// and we don't care if this is slow.
map<V3GraphVertex*,int> numMap;
// Print vertices
int n=0;
string subgr;
for (SubgraphMmap::iterator it = subgraphs.begin(); it!=subgraphs.end(); ++it) {
string vertexSubgraph = it->first;
V3GraphVertex* vertexp = it->second;
numMap[vertexp] = n;
if (subgr != vertexSubgraph) {
if (subgr!="") *logp<<"\t};\n";
subgr = vertexSubgraph;
if (subgr!="") *logp<<"\tsubgraph cluster_"<<subgr<<" {\n";
}
if (subgr!="") *logp<<"\t";
*logp<<"\tn"<<vertexp->dotName()<<(n++)
<<"\t[fontsize=8 "
<<"label=\""<<(vertexp->name()!="" ? vertexp->name() : "\\N");
if (vertexp->rank()) *logp<<" r"<<vertexp->rank();
if (vertexp->fanout()) *logp<<" f"<<vertexp->fanout();
if (vertexp->color()) *logp<<"\\n c"<<vertexp->color();
*logp<<"\"";
*logp<<", color="<<vertexp->dotColor();
if (vertexp->dotStyle()!="") *logp<<", style="<<vertexp->dotStyle();
if (vertexp->dotShape()!="") *logp<<", shape="<<vertexp->dotShape();
*logp<<"];\n";
}
if (subgr!="") *logp<<"\t};\n";
// Print edges
for (V3GraphVertex* vertexp = verticesBeginp(); vertexp; vertexp=vertexp->verticesNextp()) {
for (V3GraphEdge* edgep = vertexp->outBeginp(); edgep; edgep=edgep->outNextp()) {
if (edgep->weight()) {
int fromVnum = numMap[edgep->fromp()];
int toVnum = numMap[edgep->top()];
*logp<<"\tn"<<edgep->fromp()->dotName()<<fromVnum
<<" -> n"<<edgep->top()->dotName()<<toVnum
<<" ["
//<<"fontsize=8 label=\""<<(edgep->name()!="" ? edgep->name() : "\\E")<<"\""
<<"fontsize=8 label=\""<<(edgep->dotLabel()!="" ? edgep->dotLabel() : "")<<"\""
<<" weight="<<edgep->weight()
<<" color="<<edgep->dotColor();
if (edgep->dotStyle()!="") *logp<<" style="<<edgep->dotStyle();
//if (edgep->cutable()) { *logp<<",constraint=false"; } // to rank without following edges
*logp<<"];\n";
}
}
}
// Vertex::m_user end, now unused
// Trailer
*logp << "}\n";
logp->close();
cout << "dot -Tpdf -o ~/a.pdf "<<filename<<endl;
}
// From *this, populate *mstp with the minimum spanning tree.
// *mstp must be initially empty.
void makeMinSpanningTree(TspGraphTmpl* mstp) {
UASSERT(mstp->empty(), "Output graph must start empty");
// Use Prim's algorithm to efficiently construct the MST.
vl_unordered_set<Vertex*> visited_set;
EdgeCmp cmp;
typedef std::set<V3GraphEdge*, EdgeCmp&> PendingEdgeSet;
// This is the set of pending edges from visited to unvisited
// nodes.
PendingEdgeSet pendingEdges(cmp);
vluint32_t vertCount = 0;
for (V3GraphVertex* vxp = verticesBeginp();
vxp; vxp = vxp->verticesNextp()) {
mstp->addVertex(castVertexp(vxp)->key());
vertCount++;
}
// Choose an arbitrary start vertex and visit it;
// all incident edges from this vertex go into a pending edge set.
Vertex* start_vertexp = castVertexp(verticesBeginp());
visited_set.insert(start_vertexp);
for (V3GraphEdge* edgep = start_vertexp->outBeginp();
edgep; edgep = edgep->outNextp()) {
pendingEdges.insert(edgep);
}
// Repeatedly find the least costly edge in the pending set.
// If it connects to an unvisited node, visit that node and update
// the pending edge set. If it connects to an already visited node,
// discard it and repeat again.
unsigned edges_made = 0;
while (!pendingEdges.empty()) {
typename PendingEdgeSet::iterator firstIt = pendingEdges.begin();
V3GraphEdge* bestEdgep = *firstIt;
pendingEdges.erase(firstIt);
// bestEdgep->fromp() should be already seen
Vertex* from_vertexp = castVertexp(bestEdgep->fromp());
UASSERT(visited_set.find(from_vertexp) != visited_set.end(), "Can't find vertex");
// If the neighbor is not yet visited, visit it and add its edges
// to the pending set.
Vertex* neighborp = castVertexp(bestEdgep->top());
if (visited_set.find(neighborp) == visited_set.end()) {
int bestCost = bestEdgep->weight();
UINFO(6, "bestCost = "<<bestCost
<<" from "<<from_vertexp->key()
<<" to "<<neighborp->key()<<endl);
// Create the edge in our output MST graph
mstp->addEdge(from_vertexp->key(), neighborp->key(), bestCost);
edges_made++;
// Mark this vertex as visited
visited_set.insert(neighborp);
// Update the pending edges with new edges
for (V3GraphEdge* edgep = neighborp->outBeginp();
edgep; edgep = edgep->outNextp()) {
pendingEdges.insert(edgep);
}
} else {
UINFO(6, "Discarding edge to already-visited neighbor "
<<neighborp->key()<<endl);
}
}
UASSERT(edges_made + 1 == vertCount, "Algorithm failed");
UASSERT(visited_set.size() == vertCount, "Algorithm failed");
}
