--- /dev/null
+//===--Graph.cpp--- implements Graph class ---------------- ------*- C++ -*--=//
+//
+// This implements Graph for helping in trace generation
+// This graph gets used by "PathProfile" class
+//
+//===----------------------------------------------------------------------===//
+
+#include "Graph.h"
+#include "llvm/BasicBlock.h"
+#include <algorithm>
+
+static const graphListElement *findNodeInList(const Graph::nodeList &NL,
+ Node *N) {
+ for(Graph::nodeList::const_iterator NI = NL.begin(), NE=NL.end(); NI != NE;
+ ++NI)
+ if (*NI->element== *N)
+ return &*NI;
+ return 0;
+}
+
+static graphListElement *findNodeInList(Graph::nodeList &NL, Node *N) {
+ for(Graph::nodeList::iterator NI = NL.begin(), NE=NL.end(); NI != NE; ++NI)
+ if (*NI->element== *N)
+ return &*NI;
+ return 0;
+}
+
+//graph constructor with root and exit specified
+Graph::Graph(std::set<Node*> n, std::set<Edge> e,
+ Node *rt, Node *lt){
+ strt=rt;
+ ext=lt;
+ for(set<Node* >::iterator x=n.begin(), en=n.end(); x!=en; ++x)
+ nodes[*x] = list<graphListElement>();
+
+ for(set<Edge >::iterator x=e.begin(), en=e.end(); x!=en; ++x){
+ Edge ee=*x;
+ int w=ee.getWeight();
+ nodes[ee.getFirst()].push_front(graphListElement(ee.getSecond(),w));
+ }
+
+}
+
+//check whether graph has an edge
+//having an edge simply means that there is an edge in the graph
+//which has same endpoints as the given edge
+bool Graph::hasEdge(Edge ed) const{
+ if(ed.isNull())
+ return false;
+
+ nodeList nli=getNodeList(ed.getFirst());
+ Node *nd2=ed.getSecond();
+
+ return (findNodeInList(nli,nd2)!=NULL);
+
+}
+
+
+//check whether graph has an edge, with a given wt
+//having an edge simply means that there is an edge in the graph
+//which has same endpoints as the given edge
+//This function checks, moreover, that the wt of edge matches too
+bool Graph::hasEdgeAndWt(Edge ed) const{
+ if(ed.isNull())
+ return false;
+
+ Node *nd2=ed.getSecond();
+ nodeList nli=getNodeList(ed.getFirst());
+
+ for(nodeList::iterator NI=nli.begin(), NE=nli.end(); NI!=NE; ++NI)
+ if(*NI->element == *nd2 && ed.getWeight()==NI->weight)
+ return true;
+
+ return false;
+}
+
+//add a node
+void Graph::addNode(Node *nd){
+ list<Node *> lt=getAllNodes();
+
+ for(list<Node *>::iterator LI=lt.begin(), LE=lt.end(); LI!=LE;++LI){
+ if(**LI==*nd)
+ return;
+ }
+
+ nodes[nd] = list<graphListElement>();
+}
+
+//add an edge
+//this adds an edge ONLY when
+//the edge to be added doesn not already exist
+//we "equate" two edges here only with their
+//end points
+void Graph::addEdge(Edge ed, int w){
+ nodeList &ndList = nodes[ed.getFirst()];
+ Node *nd2=ed.getSecond();
+
+ if(findNodeInList(nodes[ed.getFirst()], nd2))
+ return;
+
+ ndList.push_front(graphListElement(nd2,w));
+}
+
+//add an edge EVEN IF such an edge already exists
+//this may make a multi-graph
+//which does happen when we add dummy edges
+//to the graph, for compensating for back-edges
+void Graph::addEdgeForce(Edge ed){
+ nodes[ed.getFirst()].push_front(graphListElement(ed.getSecond(),
+ ed.getWeight()));
+}
+
+//remove an edge
+//Note that it removes just one edge,
+//the first edge that is encountered
+void Graph::removeEdge(Edge ed){
+ nodeList &ndList = nodes[ed.getFirst()];
+ Node &nd2 = *ed.getSecond();
+
+ for(nodeList::iterator NI=ndList.begin(), NE=ndList.end(); NI!=NE ;++NI) {
+ if(*NI->element == nd2) {
+ ndList.erase(NI);
+ break;
+ }
+ }
+}
+
+//set the weight of an edge
+void Graph::setWeight(Edge ed){
+ graphListElement *El = findNodeInList(nodes[ed.getFirst()], ed.getSecond());
+ if (El)
+ El->weight=ed.getWeight();
+}
+
+
+
+//get the list of successor nodes
+list<Node *> Graph::getSuccNodes(Node *nd) const {
+ nodeMapTy::const_iterator nli = nodes.find(nd);
+ assert(nli != nodes.end() && "Node must be in nodes map");
+ const nodeList &nl = nli->second;
+
+ list<Node *> lt;
+ for(nodeList::const_iterator NI=nl.begin(), NE=nl.end(); NI!=NE; ++NI)
+ lt.push_back(NI->element);
+
+ return lt;
+}
+
+//get the list of predecessor nodes
+list<Node *> Graph::getPredNodes(Node *nd) const{
+ list<Node *> lt;
+ for(nodeMapTy::const_iterator EI=nodes.begin(), EE=nodes.end(); EI!=EE ;++EI){
+ Node *lnode=EI->first;
+ const nodeList &nl = getNodeList(lnode);
+
+ const graphListElement *N = findNodeInList(nl, nd);
+ if (N) lt.push_back(lnode);
+ }
+ return lt;
+}
+
+//get the list of all the vertices in graph
+list<Node *> Graph::getAllNodes() const{
+ list<Node *> lt;
+ for(nodeMapTy::const_iterator x=nodes.begin(), en=nodes.end(); x != en; ++x)
+ lt.push_back(x->first);
+
+ return lt;
+}
+
+
+//class to compare two nodes in graph
+//based on their wt: this is used in
+//finding the maximal spanning tree
+struct compare_nodes {
+ bool operator()(Node *n1, Node *n2){
+ return n1->getWeight() < n2->getWeight();
+ }
+};
+
+
+void printNode(Node *nd){
+ cerr<<"Node:"<<nd->getElement()->getName()<<endl;
+}
+
+//Get the Maximal spanning tree (also a graph)
+//of the graph
+Graph* Graph::getMaxSpanningTree(){
+ //assume connected graph
+
+ Graph *st=new Graph();//max spanning tree, undirected edges
+ int inf=9999999;//largest key
+ list<Node *> lt = getAllNodes();
+
+ //initially put all vertices in vector vt
+ //assign wt(root)=0
+ //wt(others)=infinity
+ //
+ //now:
+ //pull out u: a vertex frm vt of min wt
+ //for all vertices w in vt,
+ //if wt(w) greater than
+ //the wt(u->w), then assign
+ //wt(w) to be wt(u->w).
+ //
+ //make parent(u)=w in the spanning tree
+ //keep pulling out vertices from vt till it is empty
+
+ vector<Node *> vt;
+
+ map<Node*, Node* > parent;
+ map<Node*, int > ed_weight;
+
+ //initialize: wt(root)=0, wt(others)=infinity
+ //parent(root)=NULL, parent(others) not defined (but not null)
+ for(list<Node *>::iterator LI=lt.begin(), LE=lt.end(); LI!=LE; ++LI){
+ Node *thisNode=*LI;
+ if(*thisNode == *getRoot()){
+ thisNode->setWeight(0);
+ parent[thisNode]=NULL;
+ ed_weight[thisNode]=0;
+ }
+ else{
+ thisNode->setWeight(inf);
+ }
+ st->addNode(thisNode);//add all nodes to spanning tree
+ //we later need to assign edges in the tree
+ vt.push_back(thisNode); //pushed all nodes in vt
+ }
+
+ //keep pulling out vertex of min wt from vt
+ while(!vt.empty()){
+ Node *u=*(min_element(vt.begin(), vt.end(), compare_nodes()));
+#ifdef DEBUG_PATH_PROFILES
+ cerr<<"popped wt"<<(u)->getWeight()<<endl;
+ printNode(u);
+#endif
+ if(parent[u]!=NULL){ //so not root
+ Edge edge(parent[u],u, ed_weight[u]); //assign edge in spanning tree
+ st->addEdge(edge,ed_weight[u]);
+#ifdef DEBUG_PATH_PROFILES
+ cerr<<"added:\n";
+ printEdge(edge);
+#endif
+ }
+
+ //vt.erase(u);
+
+ //remove u frm vt
+ for(vector<Node *>::iterator VI=vt.begin(), VE=vt.end(); VI!=VE; ++VI){
+ if(**VI==*u){
+ vt.erase(VI);
+ break;
+ }
+ }
+
+ //assign wt(v) to all adjacent vertices v of u
+ //only if v is in vt
+ Graph::nodeList nl=getNodeList(u);
+ for(nodeList::iterator NI=nl.begin(), NE=nl.end(); NI!=NE; ++NI){
+ Node *v=NI->element;
+ int weight=-NI->weight;
+ //check if v is in vt
+ bool contains=false;
+ for(vector<Node *>::iterator VI=vt.begin(), VE=vt.end(); VI!=VE; ++VI){
+ if(**VI==*v){
+ contains=true;
+ break;
+ }
+ }
+#ifdef DEBUG_PATH_PROFILES
+ cerr<<"wt:v->wt"<<weight<<":"<<v->getWeight()<<endl;
+ printNode(v);cerr<<"node wt:"<<(*v).weight<<endl;
+#endif
+ //so if v in in vt, change wt(v) to wt(u->v)
+ //only if wt(u->v)<wt(v)
+ if(contains && weight<v->getWeight()){
+ parent[v]=u;
+ ed_weight[v]=weight;
+ v->setWeight(weight);
+#ifdef DEBUG_PATH_PROFILES
+ cerr<<v->getWeight()<<":Set weight------\n";
+ printGraph();
+ printEdge(Edge(u,v,weight));
+#endif
+ }
+ }
+ }
+ return st;
+}
+
+//print the graph (for debugging)
+void Graph::printGraph(){
+ list<Node *> lt=getAllNodes();
+ cerr<<"Graph---------------------\n";
+ for(list<Node *>::iterator LI=lt.begin(), LE=lt.end(); LI!=LE; ++LI){
+ cerr<<((*LI)->getElement())->getName()<<"->";
+ Graph::nodeList nl=getNodeList(*LI);
+ for(Graph::nodeList::iterator NI=nl.begin(), NE=nl.end(); NI!=NE; ++NI){
+ cerr<<":"<<"("<<(NI->element->getElement())
+ ->getName()<<":"<<NI->element->getWeight()<<","<<NI->weight<<")";
+ }
+ cerr<<"--------\n";
+ }
+}
+
+
+//get a list of nodes in the graph
+//in r-topological sorted order
+//note that we assumed graph to be connected
+list<Node *> Graph::reverseTopologicalSort() const{
+ list <Node *> toReturn;
+ list<Node *> lt=getAllNodes();
+ for(list<Node *>::iterator LI=lt.begin(), LE=lt.end(); LI!=LE; ++LI){
+ if((*LI)->getWeight()!=GREY && (*LI)->getWeight()!=BLACK)
+ DFS_Visit(*LI, toReturn);
+ }
+ return toReturn;
+}
+
+//a private method for doing DFS traversal of graph
+//this is used in determining the reverse topological sort
+//of the graph
+void Graph::DFS_Visit(Node *nd, list<Node *> &toReturn) const {
+ nd->setWeight(GREY);
+ list<Node *> lt=getSuccNodes(nd);
+ for(list<Node *>::iterator LI=lt.begin(), LE=lt.end(); LI!=LE; ++LI){
+ if((*LI)->getWeight()!=GREY && (*LI)->getWeight()!=BLACK)
+ DFS_Visit(*LI, toReturn);
+ }
+ toReturn.push_back(nd);
+}
+
+//Ordinarily, the graph is directional
+//this converts the graph into an
+//undirectional graph
+//This is done by adding an edge
+//v->u for all existing edges u->v
+void Graph::makeUnDirectional(){
+ list<Node* > allNodes=getAllNodes();
+ for(list<Node *>::iterator NI=allNodes.begin(), NE=allNodes.end(); NI!=NE;
+ ++NI) {
+ nodeList nl=getNodeList(*NI);
+ for(nodeList::iterator NLI=nl.begin(), NLE=nl.end(); NLI!=NLE; ++NLI){
+ Edge ed(NLI->element, *NI, NLI->weight);
+ if(!hasEdgeAndWt(ed)){
+#ifdef DEBUG_PATH_PROFILES
+ cerr<<"######doesn't hv\n";
+ printEdge(ed);
+#endif
+ addEdgeForce(ed);
+ }
+ }
+ }
+}
+
+//reverse the sign of weights on edges
+//this way, max-spanning tree could be obtained
+//usin min-spanning tree, and vice versa
+void Graph::reverseWts(){
+ list<Node *> allNodes=getAllNodes();
+ for(list<Node *>::iterator NI=allNodes.begin(), NE=allNodes.end(); NI!=NE;
+ ++NI) {
+ nodeList node_list=getNodeList(*NI);
+ for(nodeList::iterator NLI=nodes[*NI].begin(), NLE=nodes[*NI].end();
+ NLI!=NLE; ++NLI)
+ NLI->weight=-NLI->weight;
+ }
+}
+
+
+//getting the backedges in a graph
+//Its a variation of DFS to get the backedges in the graph
+//We get back edges by associating a time
+//and a color with each vertex.
+//The time of a vertex is the time when it was first visited
+//The color of a vertex is initially WHITE,
+//Changes to GREY when it is first visited,
+//and changes to BLACK when ALL its neighbors
+//have been visited
+//So we have a back edge when we meet a successor of
+//a node with smaller time, and GREY color
+void Graph::getBackEdges(vector<Edge > &be) const{
+ map<Node *, Color > color;
+ map<Node *, int > d;
+ list<Node *> allNodes=getAllNodes();
+ int time=0;
+ for(list<Node *>::const_iterator NI=allNodes.begin(), NE=allNodes.end();
+ NI!=NE; ++NI){
+ if(color[*NI]!=GREY && color[*NI]!=BLACK)
+ getBackEdgesVisit(*NI, be, color, d, time);
+ }
+}
+
+//helper function to get back edges: it is called by
+//the "getBackEdges" function above
+void Graph::getBackEdgesVisit(Node *u, vector<Edge > &be,
+ map<Node *, Color > &color,
+ map<Node *, int > &d, int &time) const{
+ color[u]=GREY;
+ time++;
+ d[u]=time;
+ list<Node *> succ_list=getSuccNodes(u);
+
+ for(list<Node *>::const_iterator v=succ_list.begin(), ve=succ_list.end();
+ v!=ve; ++v){
+ if(color[*v]!=GREY && color[*v]!=BLACK){
+ getBackEdgesVisit(*v, be, color, d, time);
+ }
+
+ //now checking for d and f vals
+ if(color[*v]==GREY){
+ //so v is ancestor of u if time of u > time of v
+ if(d[u] >= d[*v]){
+ Edge *ed=new Edge(u, *v);
+ if (!(*u == *getExit() && **v == *getRoot()))
+ be.push_back(*ed); // choose the forward edges
+ }
+ }
+ }
+ color[u]=BLACK;//done with visiting the node and its neighbors
+}
+
+
projects / oota-llvm.git / commitdiff