bool _removeUnusedFromModule()
{
using namespace llvm;
// do not slice away these functions no matter what
// FIXME do it a vector and fill it dynamically according
// to what is the setup (like for sv-comp or general..)
const char *keep[] = {options.dgOptions.entryFunction.c_str(),
"klee_assume", nullptr};
// when erasing while iterating the slicer crashes
// so set the to be erased values into container
// and then erase them
std::set<Function *> funs;
std::set<GlobalVariable *> globals;
std::set<GlobalAlias *> aliases;
for (auto I = M->begin(), E = M->end(); I != E; ++I) {
Function *func = &*I;
if (array_match(func->getName(), keep))
continue;
// if the function is unused or we haven't constructed it
// at all in dependence graph, we can remove it
// (it may have some uses though - like when one
// unused func calls the other unused func
if (func->hasNUses(0))
funs.insert(func);
}
for (auto I = M->global_begin(), E = M->global_end(); I != E; ++I) {
GlobalVariable *gv = &*I;
if (gv->hasNUses(0))
globals.insert(gv);
}
for (GlobalAlias& ga : M->getAliasList()) {
if (ga.hasNUses(0))
aliases.insert(&ga);
}
for (Function *f : funs)
f->eraseFromParent();
for (GlobalVariable *gv : globals)
gv->eraseFromParent();
for (GlobalAlias *ga : aliases)
ga->eraseFromParent();
return (!funs.empty() || !globals.empty() || !aliases.empty());
}
