llvm-6502/lib/Transforms/Instrumentation/ProfilePaths/GraphAuxiliary.cpp
2002-02-26 19:49:45 +00:00

646 lines
19 KiB
C++

//===-- GrapAuxillary.cpp- Auxillary functions on graph ----------*- C++ -*--=//
//
//auxillary function associated with graph: they
//all operate on graph, and help in inserting
//instrumentation for trace generation
//
//===----------------------------------------------------------------------===//
#include "Graph.h"
#include "llvm/BasicBlock.h"
#include <algorithm>
#include <iostream>
using std::list;
using std::map;
using std::vector;
using std::cerr;
//check if 2 edges are equal (same endpoints and same weight)
static bool edgesEqual(Edge ed1, Edge ed2){
return ((ed1==ed2) && ed1.getWeight()==ed2.getWeight());
}
//Get the vector of edges that are to be instrumented in the graph
static void getChords(vector<Edge > &chords, Graph &g, Graph st){
//make sure the spanning tree is directional
//iterate over ALL the edges of the graph
list<Node *> allNodes=g.getAllNodes();
for(list<Node *>::iterator NI=allNodes.begin(), NE=allNodes.end(); NI!=NE;
++NI){
Graph::nodeList node_list=g.getNodeList(*NI);
for(Graph::nodeList::iterator NLI=node_list.begin(), NLE=node_list.end();
NLI!=NLE; ++NLI){
Edge f(*NI, NLI->element,NLI->weight);
if(!(st.hasEdgeAndWt(f)))//addnl
chords.push_back(f);
}
}
}
//Given a tree t, and a "directed graph" g
//replace the edges in the tree t with edges that exist in graph
//The tree is formed from "undirectional" copy of graph
//So whatever edges the tree has, the undirectional graph
//would have too. This function corrects some of the directions in
//the tree so that now, all edge directions in the tree match
//the edge directions of corresponding edges in the directed graph
static void removeTreeEdges(Graph &g, Graph& t){
list<Node* > allNodes=t.getAllNodes();
for(list<Node *>::iterator NI=allNodes.begin(), NE=allNodes.end(); NI!=NE;
++NI){
Graph::nodeList nl=t.getNodeList(*NI);
for(Graph::nodeList::iterator NLI=nl.begin(), NLE=nl.end(); NLI!=NLE;++NLI){
Edge ed(NLI->element, *NI, NLI->weight);
//if(!g.hasEdge(ed)) t.removeEdge(ed);
if(!g.hasEdgeAndWt(ed)) t.removeEdge(ed);//tree has only one edge
//between any pair of vertices, so no need to delete by edge wt
}
}
}
//Assign a value to all the edges in the graph
//such that if we traverse along any path from root to exit, and
//add up the edge values, we get a path number that uniquely
//refers to the path we travelled
int valueAssignmentToEdges(Graph& g){
list<Node *> revtop=g.reverseTopologicalSort();
map<Node *,int > NumPaths;
for(list<Node *>::iterator RI=revtop.begin(), RE=revtop.end(); RI!=RE; ++RI){
if(g.isLeaf(*RI))
NumPaths[*RI]=1;
else{
NumPaths[*RI]=0;
list<Node *> succ=g.getSuccNodes(*RI);
for(list<Node *>::iterator SI=succ.begin(), SE=succ.end(); SI!=SE; ++SI){
Edge ed(*RI,*SI,NumPaths[*RI]);
g.setWeight(ed);
NumPaths[*RI]+=NumPaths[*SI];
}
}
}
return NumPaths[g.getRoot()];
}
//This is a helper function to get the edge increments
//This is used in conjuntion with inc_DFS
//to get the edge increments
//Edge increment implies assigning a value to all the edges in the graph
//such that if we traverse along any path from root to exit, and
//add up the edge values, we get a path number that uniquely
//refers to the path we travelled
//inc_Dir tells whether 2 edges are in same, or in different directions
//if same direction, return 1, else -1
static int inc_Dir(Edge e, Edge f){
if(e.isNull())
return 1;
//check that the edges must have atleast one common endpoint
assert(*(e.getFirst())==*(f.getFirst()) ||
*(e.getFirst())==*(f.getSecond()) ||
*(e.getSecond())==*(f.getFirst()) ||
*(e.getSecond())==*(f.getSecond()));
if(*(e.getFirst())==*(f.getSecond()) ||
*(e.getSecond())==*(f.getFirst()))
return 1;
return -1;
}
//used for getting edge increments (read comments above in inc_Dir)
//inc_DFS is a modification of DFS
static void inc_DFS(Graph& g,Graph& t,map<Edge, int>& Increment,
int events, Node *v, Edge e){
list<Node *> allNodes=t.getAllNodes();
for(list<Node *>::iterator NI=allNodes.begin(), NE=allNodes.end(); NI!=NE;
++NI){
Graph::nodeList node_list=t.getNodeList(*NI);
for(Graph::nodeList::iterator NLI=node_list.begin(), NLE=node_list.end();
NLI!= NLE; ++NLI){
Edge f(*NI, NLI->element,NLI->weight);
if(!edgesEqual(f,e) && *v==*(f.getSecond())){
int dir_count=inc_Dir(e,f);
int wt=1*f.getWeight();
inc_DFS(g,t, Increment, dir_count*events+wt, f.getFirst(), f);
}
}
}
for(list<Node *>::iterator NI=allNodes.begin(), NE=allNodes.end(); NI!=NE;
++NI){
Graph::nodeList node_list=t.getNodeList(*NI);
for(Graph::nodeList::iterator NLI=node_list.begin(), NLE=node_list.end();
NLI!=NLE; ++NLI){
Edge f(*NI, NLI->element,NLI->weight);
if(!edgesEqual(f,e) && *v==*(f.getFirst())){
int dir_count=inc_Dir(e,f);
int wt=1*f.getWeight();
inc_DFS(g,t, Increment, dir_count*events+wt,
f.getSecond(), f);
}
}
}
allNodes=g.getAllNodes();
for(list<Node *>::iterator NI=allNodes.begin(), NE=allNodes.end(); NI!=NE;
++NI){
Graph::nodeList node_list=g.getNodeList(*NI);
for(Graph::nodeList::iterator NLI=node_list.begin(), NLE=node_list.end();
NLI!=NLE; ++NLI){
Edge f(*NI, NLI->element,NLI->weight);
if(!(t.hasEdgeAndWt(f)) && (*v==*(f.getSecond()) ||
*v==*(f.getFirst()))){
int dir_count=inc_Dir(e,f);
Increment[f]+=dir_count*events;
}
}
}
}
//Now we select a subset of all edges
//and assign them some values such that
//if we consider just this subset, it still represents
//the path sum along any path in the graph
static map<Edge, int> getEdgeIncrements(Graph& g, Graph& t){
//get all edges in g-t
map<Edge, int> Increment;
list<Node *> allNodes=g.getAllNodes();
for(list<Node *>::iterator NI=allNodes.begin(), NE=allNodes.end(); NI!=NE;
++NI){
Graph::nodeList node_list=g.getNodeList(*NI);
for(Graph::nodeList::iterator NLI=node_list.begin(), NLE=node_list.end();
NLI!=NLE; ++NLI){
Edge ed(*NI, NLI->element,NLI->weight);
if(!(t.hasEdge(ed))){
Increment[ed]=0;;
}
}
}
Edge *ed=new Edge();
inc_DFS(g,t,Increment, 0, g.getRoot(), *ed);
for(list<Node *>::iterator NI=allNodes.begin(), NE=allNodes.end(); NI!=NE;
++NI){
Graph::nodeList node_list=g.getNodeList(*NI);
for(Graph::nodeList::iterator NLI=node_list.begin(), NLE=node_list.end();
NLI!=NLE; ++NLI){
Edge ed(*NI, NLI->element,NLI->weight);
if(!(t.hasEdge(ed))){
int wt=ed.getWeight();
Increment[ed]+=wt;
}
}
}
return Increment;
}
//Based on edgeIncrements (above), now obtain
//the kind of code to be inserted along an edge
//The idea here is to minimize the computation
//by inserting only the needed code
static void getCodeInsertions(Graph &g, map<Edge, getEdgeCode *> &instr,
vector<Edge > &chords,
map<Edge,int> &edIncrements){
//Register initialization code
vector<Node *> ws;
ws.push_back(g.getRoot());
while(ws.size()>0){
Node *v=ws.back();
ws.pop_back();
//for each edge v->w
Graph::nodeList succs=g.getNodeList(v);
for(Graph::nodeList::iterator nl=succs.begin(), ne=succs.end();
nl!=ne; ++nl){
int edgeWt=nl->weight;
Node *w=nl->element;
//if chords has v->w
Edge ed(v,w);
bool hasEdge=false;
for(vector<Edge>::iterator CI=chords.begin(), CE=chords.end();
CI!=CE && !hasEdge;++CI){
if(*CI==ed){
hasEdge=true;
}
}
if(hasEdge){
getEdgeCode *edCd=new getEdgeCode();
edCd->setCond(1);
edCd->setInc(edIncrements[ed]);
instr[ed]=edCd;
}
else if((g.getPredNodes(w)).size()==1){
ws.push_back(w);
}
else{
getEdgeCode *edCd=new getEdgeCode();
edCd->setCond(2);
edCd->setInc(0);
instr[ed]=edCd;
}
}
}
/////Memory increment code
ws.push_back(g.getExit());
while(!ws.empty()) {
Node *w=ws.back();
ws.pop_back();
//for each edge v->w
list<Node *> preds=g.getPredNodes(w);
for(list<Node *>::iterator pd=preds.begin(), pe=preds.end(); pd!=pe; ++pd){
Node *v=*pd;
//if chords has v->w
Edge ed(v,w);
getEdgeCode *edCd=new getEdgeCode();
bool hasEdge=false;
for(vector<Edge>::iterator CI=chords.begin(), CE=chords.end(); CI!=CE;
++CI){
if(*CI==ed){
hasEdge=true;
break;
}
}
if(hasEdge){
char str[100];
if(instr[ed]!=NULL && instr[ed]->getCond()==1){
instr[ed]->setCond(4);
}
else{
edCd->setCond(5);
edCd->setInc(edIncrements[ed]);
instr[ed]=edCd;
}
}
else if(g.getSuccNodes(v).size()==1)
ws.push_back(v);
else{
edCd->setCond(6);
instr[ed]=edCd;
}
}
}
///// Register increment code
for(vector<Edge>::iterator CI=chords.begin(), CE=chords.end(); CI!=CE; ++CI){
getEdgeCode *edCd=new getEdgeCode();
if(instr[*CI]==NULL){
edCd->setCond(3);
edCd->setInc(edIncrements[*CI]);
instr[*CI]=edCd;
}
}
}
//Add dummy edges corresponding to the back edges
//If a->b is a backedge
//then incoming dummy edge is root->b
//and outgoing dummy edge is a->exit
void addDummyEdges(vector<Edge > &stDummy,
vector<Edge > &exDummy,
Graph &g, vector<Edge> &be){
for(vector<Edge >::iterator VI=be.begin(), VE=be.end(); VI!=VE; ++VI){
Edge ed=*VI;
Node *first=ed.getFirst();
Node *second=ed.getSecond();
g.removeEdge(ed);
if(!(*second==*(g.getRoot()))){
Edge *st=new Edge(g.getRoot(), second);
//check if stDummy doesn't have it already
if(find(stDummy.begin(), stDummy.end(), *st) == stDummy.end())
stDummy.push_back(*st);
g.addEdgeForce(*st);
}
if(!(*first==*(g.getExit()))){
Edge *ex=new Edge(first, g.getExit());
if (find(exDummy.begin(), exDummy.end(), *ex) == exDummy.end()) {
exDummy.push_back(*ex);
g.addEdgeForce(*ex);
}
}
}
}
//print a given edge in the form BB1Label->BB2Label
void printEdge(Edge ed){
cerr<<((ed.getFirst())->getElement())
->getName()<<"->"<<((ed.getSecond())
->getElement())->getName()<<
":"<<ed.getWeight()<<"\n";
}
//Move the incoming dummy edge code and outgoing dummy
//edge code over to the corresponding back edge
static void moveDummyCode(const vector<Edge> &stDummy,
const vector<Edge> &exDummy,
const vector<Edge> &be,
map<Edge, getEdgeCode *> &insertions){
typedef vector<Edge >::const_iterator vec_iter;
#ifdef DEBUG_PATH_PROFILES
//print all back, st and ex dummy
cerr<<"BackEdges---------------\n";
for(vec_iter VI=be.begin(); VI!=be.end(); ++VI)
printEdge(*VI);
cerr<<"StEdges---------------\n";
for(vec_iter VI=stDummy.begin(); VI!=stDummy.end(); ++VI)
printEdge(*VI);
cerr<<"ExitEdges---------------\n";
for(vec_iter VI=exDummy.begin(); VI!=exDummy.end(); ++VI)
printEdge(*VI);
cerr<<"------end all edges\n";
#endif
std::vector<Edge> toErase;
for(map<Edge,getEdgeCode *>::iterator MI=insertions.begin(),
ME=insertions.end(); MI!=ME; ++MI){
Edge ed=MI->first;
getEdgeCode *edCd=MI->second;
bool dummyHasIt=false;
#ifdef DEBUG_PATH_PROFILES
cerr<<"Current edge considered---\n";
printEdge(ed);
#endif
//now check if stDummy has ed
for(vec_iter VI=stDummy.begin(), VE=stDummy.end(); VI!=VE && !dummyHasIt;
++VI){
if(*VI==ed){
#ifdef DEBUG_PATH_PROFILES
cerr<<"Edge matched with stDummy\n";
#endif
dummyHasIt=true;
bool dummyInBe=false;
//dummy edge with code
for(vec_iter BE=be.begin(), BEE=be.end(); BE!=BEE && !dummyInBe; ++BE){
Edge backEdge=*BE;
Node *st=backEdge.getSecond();
Node *dm=ed.getSecond();
if(*dm==*st){
//so this is the back edge to use
#ifdef DEBUG_PATH_PROFILES
cerr<<"Moving to backedge\n";
printEdge(backEdge);
#endif
getEdgeCode *ged=new getEdgeCode();
ged->setCdIn(edCd);
toErase.push_back(ed);
insertions[backEdge]=ged;
dummyInBe=true;
}
}
assert(dummyInBe);
}
}
if(!dummyHasIt){
//so exDummy may hv it
bool inExDummy=false;
for(vec_iter VI=exDummy.begin(), VE=exDummy.end(); VI!=VE && !inExDummy;
++VI){
if(*VI==ed){
inExDummy=true;
#ifdef DEBUG_PATH_PROFILES
cerr<<"Edge matched with exDummy\n";
#endif
bool dummyInBe2=false;
//dummy edge with code
for(vec_iter BE=be.begin(), BEE=be.end(); BE!=BEE && !dummyInBe2;
++BE){
Edge backEdge=*BE;
Node *st=backEdge.getFirst();
Node *dm=ed.getFirst();
if(*dm==*st){
//so this is the back edge to use
getEdgeCode *ged;
if(insertions[backEdge]==NULL)
ged=new getEdgeCode();
else
ged=insertions[backEdge];
toErase.push_back(ed);
ged->setCdOut(edCd);
insertions[backEdge]=ged;
dummyInBe2=true;
}
}
assert(dummyInBe2);
}
}
}
}
#ifdef DEBUG_PATH_PROFILES
cerr<<"size of deletions: "<<toErase.size()<<"\n";
#endif
for(vector<Edge >::iterator vmi=toErase.begin(), vme=toErase.end(); vmi!=vme;
++vmi)
insertions.erase(*vmi);
#ifdef DEBUG_PATH_PROFILES
cerr<<"SIZE OF INSERTIONS AFTER DEL "<<insertions.size()<<"\n";
#endif
}
//Do graph processing: to determine minimal edge increments,
//appropriate code insertions etc and insert the code at
//appropriate locations
void processGraph(Graph &g,
Instruction *rInst,
Instruction *countInst,
vector<Edge >& be,
vector<Edge >& stDummy,
vector<Edge >& exDummy){
//Given a graph: with exit->root edge, do the following in seq:
//1. get back edges
//2. insert dummy edges and remove back edges
//3. get edge assignments
//4. Get Max spanning tree of graph:
// -Make graph g2=g undirectional
// -Get Max spanning tree t
// -Make t undirectional
// -remove edges from t not in graph g
//5. Get edge increments
//6. Get code insertions
//7. move code on dummy edges over to the back edges
//This is used as maximum "weight" for
//priority queue
//This would hold all
//right as long as number of paths in the graph
//is less than this
const int INFINITY=99999999;
//step 1-3 are already done on the graph when this function is called
#ifdef DEBUG_PATH_PROFILES
printGraph(g);
#endif
//step 4: Get Max spanning tree of graph
//now insert exit to root edge
//if its there earlier, remove it!
//assign it weight INFINITY
//so that this edge IS ALWAYS IN spanning tree
//Note than edges in spanning tree do not get
//instrumented: and we do not want the
//edge exit->root to get instrumented
//as it MAY BE a dummy edge
Edge ed(g.getExit(),g.getRoot(),INFINITY);
g.addEdge(ed,INFINITY);
Graph g2=g;
//make g2 undirectional: this gives a better
//maximal spanning tree
g2.makeUnDirectional();
#ifdef DEBUG_PATH_PROFILES
printGraph(g2);
#endif
Graph *t=g2.getMaxSpanningTree();
#ifdef DEBUG_PATH_PROFILES
printGraph(*t);
#endif
//now edges of tree t have weights reversed
//(negative) because the algorithm used
//to find max spanning tree is
//actually for finding min spanning tree
//so get back the original weights
t->reverseWts();
//Ordinarily, the graph is directional
//lets converts the graph into an
//undirectional graph
//This is done by adding an edge
//v->u for all existing edges u->v
t->makeUnDirectional();
//Given a tree t, and a "directed graph" g
//replace the edges in the tree t with edges that exist in graph
//The tree is formed from "undirectional" copy of graph
//So whatever edges the tree has, the undirectional graph
//would have too. This function corrects some of the directions in
//the tree so that now, all edge directions in the tree match
//the edge directions of corresponding edges in the directed graph
removeTreeEdges(g, *t);
#ifdef DEBUG_PATH_PROFILES
cerr<<"Spanning tree---------\n";
printGraph(*t);
cerr<<"-------end spanning tree\n";
#endif
//now remove the exit->root node
//and re-add it with weight 0
//since infinite weight is kinda confusing
g.removeEdge(ed);
Edge edNew(g.getExit(), g.getRoot(),0);
g.addEdge(edNew,0);
if(t->hasEdge(ed)){
t->removeEdge(ed);
t->addEdge(edNew,0);
}
#ifdef DEBUG_PATH_PROFILES
printGraph(g);
printGraph(*t);
#endif
//step 5: Get edge increments
//Now we select a subset of all edges
//and assign them some values such that
//if we consider just this subset, it still represents
//the path sum along any path in the graph
map<Edge, int> increment=getEdgeIncrements(g,*t);
#ifdef DEBUG_PATH_PROFILES
//print edge increments for debugging
for(map<Edge, int>::iterator M_I=increment.begin(), M_E=increment.end();
M_I!=M_E; ++M_I){
printEdge(M_I->first);
cerr<<"Increment for above:"<<M_I->second<<"\n";
}
#endif
//step 6: Get code insertions
//Based on edgeIncrements (above), now obtain
//the kind of code to be inserted along an edge
//The idea here is to minimize the computation
//by inserting only the needed code
vector<Edge> chords;
getChords(chords, g, *t);
map<Edge, getEdgeCode *> codeInsertions;
getCodeInsertions(g, codeInsertions, chords,increment);
#ifdef DEBUG_PATH_PROFILES
//print edges with code for debugging
cerr<<"Code inserted in following---------------\n";
for(map<Edge, getEdgeCode *>::iterator cd_i=codeInsertions->begin(),
cd_e=codeInsertions->end(); cd_i!=cd_e; ++cd_i){
printEdge(cd_i->first);
cerr<<cd_i->second->getCond()<<":"<<cd_i->second->getInc()<<"\n";
}
cerr<<"-----end insertions\n";
#endif
//step 7: move code on dummy edges over to the back edges
//Move the incoming dummy edge code and outgoing dummy
//edge code over to the corresponding back edge
moveDummyCode(stDummy, exDummy, be, codeInsertions);
#ifdef DEBUG_PATH_PROFILES
//debugging info
cerr<<"After moving dummy code\n";
for(map<Edge, getEdgeCode *>::iterator cd_i=codeInsertions.begin(),
cd_e=codeInsertions.end(); cd_i != cd_e; ++cd_i){
printEdge(cd_i->first);
cerr<<cd_i->second->getCond()<<":"
<<cd_i->second->getInc()<<"\n";
}
cerr<<"Dummy end------------\n";
#endif
//see what it looks like...
//now insert code along edges which have codes on them
for(map<Edge, getEdgeCode *>::iterator MI=codeInsertions.begin(),
ME=codeInsertions.end(); MI!=ME; ++MI){
Edge ed=MI->first;
insertBB(ed, MI->second, rInst, countInst);
}
}
//print the graph (for debugging)
void printGraph(Graph &g){
list<Node *> lt=g.getAllNodes();
cerr<<"Graph---------------------\n";
for(list<Node *>::iterator LI=lt.begin();
LI!=lt.end(); ++LI){
cerr<<((*LI)->getElement())->getName()<<"->";
Graph::nodeList nl=g.getNodeList(*LI);
for(Graph::nodeList::iterator NI=nl.begin();
NI!=nl.end(); ++NI){
cerr<<":"<<"("<<(NI->element->getElement())
->getName()<<":"<<NI->element->getWeight()<<","<<NI->weight<<")";
}
cerr<<"\n";
}
cerr<<"--------------------Graph\n";
}