SCCP.cpp

  for (DenseMap<GlobalVariable*, LatticeVal>::const_iterator I = TG.begin(),
         E = TG.end(); I != E; ++I) {
    GlobalVariable *GV = I->first;
    assert(!I->second.isOverdefined() &&
           "Overdefined values should have been taken out of the map!");
    DEBUG(dbgs() << "Found that GV '" << GV->getName() << "' is constant!\n");
    while (!GV->use_empty()) {
      StoreInst *SI = cast<StoreInst>(GV->use_back());
      SI->eraseFromParent();
    }
    M.getGlobalList().erase(GV);
    ++IPNumGlobalConst;
  }

  return MadeChanges;
}