// Iterate through all possible paths in the dag
void LSTMStaticEstimatorPass::calculatePaths(BLInstrumentationDag* dag) {
unsigned nPaths = dag->getNumberOfPaths();
errs() << "There are " << nPaths << " paths\n";
int stride = nPaths / MAX_PATHS;
if (stride <= 1)
stride = 1;
errs() << "Using stride " << stride << "\n";
Function* fn = dag->getRoot()->getBlock()->getParent();
PI->setCurrentFunction(fn);
unsigned nPathsRun = PI->pathsRun();
if (nPathsRun == 0) {
errs() << "This function is never run in profiling! Skipping...\n";
}
else {
int n_extracted = 0;
// Enumerate all paths in this function
for (int i=0; i<nPaths; i++) {
// Show progress for large values
if (i % 10000000 == 0 && i != 0) {
errs() << "Computed for " << i << "/" << nPaths << " paths\n";
}
ProfilePath* curPath = PI->getPath(i);
unsigned n_real_count = 0;
if (curPath) {
n_real_count = curPath->getCount();
}
// We need to subsample the paths, but only if this isn't a pos example
bool extract = false;
if (n_real_count == 0) {
if (i % stride == 0) {
extract = true;
}
} else {
extract = true;
}
if (extract) {
//compute the exact path
std::vector<BasicBlock*> path = computePath(dag, i);
// Extract features
FeatureExtractor* features = new FeatureExtractor(path);
std::string fnName = fn->getName();
ofs << fnName << " " << i << " " // Function ID
<< n_real_count << " " // Ground truth
<< path.size() << "\n" // Number of BB to follow
<< features->getFeaturesLSTM(); // BBs and features
delete features;
n_extracted++;
}
}
errs() << "Extracted " << n_extracted << " paths for this function\n\n";
}
}
// the verifier iterates through each path to gather the total
// number of edge frequencies
bool PathProfileVerifier::runOnModule (Module &M) {
PathProfileInfo& pathProfileInfo = getAnalysis<PathProfileInfo>();
// setup a data structure to map path edges which index an
// array of edge counters
NestedBlockToIndexMap arrayMap;
unsigned i = 0;
for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F) {
if (F->isDeclaration()) continue;
arrayMap[0][F->begin()][0] = i++;
for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
TerminatorInst *TI = BB->getTerminator();
unsigned duplicate = 0;
BasicBlock* prev = 0;
for (unsigned s = 0, e = TI->getNumSuccessors(); s != e;
prev = TI->getSuccessor(s), ++s) {
if (prev == TI->getSuccessor(s))
duplicate++;
else duplicate = 0;
arrayMap[BB][TI->getSuccessor(s)][duplicate] = i++;
}
}
}
std::vector<unsigned> edgeArray(i);
// iterate through each path and increment the edge counters as needed
for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F) {
if (F->isDeclaration()) continue;
pathProfileInfo.setCurrentFunction(F);
DEBUG(dbgs() << "function '" << F->getName() << "' ran "
<< pathProfileInfo.pathsRun()
<< "/" << pathProfileInfo.getPotentialPathCount()
<< " potential paths\n");
for( ProfilePathIterator nextPath = pathProfileInfo.pathBegin(),
endPath = pathProfileInfo.pathEnd();
nextPath != endPath; nextPath++ ) {
ProfilePath* currentPath = nextPath->second;
ProfilePathEdgeVector* pev = currentPath->getPathEdges();
DEBUG(dbgs () << "path #" << currentPath->getNumber() << ": "
<< currentPath->getCount() << "\n");
// setup the entry edge (normally path profiling doesn't care about this)
if (currentPath->getFirstBlockInPath() == &F->getEntryBlock())
edgeArray[arrayMap[0][currentPath->getFirstBlockInPath()][0]]
+= currentPath->getCount();
for( ProfilePathEdgeIterator nextEdge = pev->begin(),
endEdge = pev->end(); nextEdge != endEdge; nextEdge++ ) {
if (nextEdge != pev->begin())
DEBUG(dbgs() << " :: ");
BasicBlock* source = nextEdge->getSource();
BasicBlock* target = nextEdge->getTarget();
unsigned duplicateNumber = nextEdge->getDuplicateNumber();
DEBUG(dbgs() << source->getName() << " --{" << duplicateNumber
<< "}--> " << target->getName());
// Ensure all the referenced edges exist
// TODO: make this a separate function
if( !arrayMap.count(source) ) {
errs() << " error [" << F->getName() << "()]: source '"
<< source->getName()
<< "' does not exist in the array map.\n";
} else if( !arrayMap[source].count(target) ) {
errs() << " error [" << F->getName() << "()]: target '"
<< target->getName()
<< "' does not exist in the array map.\n";
} else if( !arrayMap[source][target].count(duplicateNumber) ) {
errs() << " error [" << F->getName() << "()]: edge "
<< source->getName() << " -> " << target->getName()
<< " duplicate number " << duplicateNumber
<< " does not exist in the array map.\n";
} else {
edgeArray[arrayMap[source][target][duplicateNumber]]
+= currentPath->getCount();
}
}
DEBUG(errs() << "\n");
delete pev;
}
}
std::string errorInfo;
std::string filename = EdgeProfileFilename;
// Open a handle to the file
FILE* edgeFile = fopen(filename.c_str(),"wb");
if (!edgeFile) {
errs() << "error: unable to open file '" << filename << "' for output.\n";
return false;
}
errs() << "Generating edge profile '" << filename << "' ...\n";
// write argument info
unsigned type = ArgumentInfo;
unsigned num = pathProfileInfo.argList.size();
int zeros = 0;
fwrite(&type,sizeof(unsigned),1,edgeFile);
fwrite(&num,sizeof(unsigned),1,edgeFile);
fwrite(pathProfileInfo.argList.c_str(),1,num,edgeFile);
if (num&3)
fwrite(&zeros, 1, 4-(num&3), edgeFile);
type = EdgeInfo;
num = edgeArray.size();
fwrite(&type,sizeof(unsigned),1,edgeFile);
fwrite(&num,sizeof(unsigned),1,edgeFile);
// write each edge to the file
for( std::vector<unsigned>::iterator s = edgeArray.begin(),
e = edgeArray.end(); s != e; s++)
fwrite(&*s, sizeof (unsigned), 1, edgeFile);
fclose (edgeFile);
return true;
}
